FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Southward, RE Thompson, DW AF Southward, RE Thompson, DW TI Metal-polyimide nanocomposite films: Single-stage synthesis of silvered polyimide films prepared from silver(I) complexes and BPDA/4,4 '-ODA SO CHEMISTRY OF MATERIALS LA English DT Article ID POLYMERIC FILMS AB Highly reflective and surface conductive flexible polyimide films have been prepared by the incorporation of silver(I) acetate and 1,1,1-trifluoro-2,4-pentanedione or 1,1,1,5,5,5-hexafluoro-2,4-pentanedione into a dimethylacetamide solution of the poly(amic acid) formed from 3,3',4,4'-biphenyltetracarboxylic dianhydride and 4,4'-oxydianiline. Thermal curing of the silver(I)-containing poly(amic acid) leads to cycloimidization of the polyimide precursor with concomitant silver(I) reduction yielding reflective and conductive silvered surfaces with properties approaching those of the native metal. The metallized films usually exhibit mechanical and thermal properties close to that of the parent polyimide. Films were characterized by X-ray diffraction, transmission and scanning electron microscopy, and X-ray photoelectron spectroscopy. C1 NASA, Langley Res Ctr, Struct & Mat Competency, Hampton, VA 23681 USA. Coll William & Mary, Dept Chem, Williamsburg, VA 23187 USA. RP Southward, RE (reprint author), NASA, Langley Res Ctr, Struct & Mat Competency, Hampton, VA 23681 USA. NR 25 TC 46 Z9 48 U1 2 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD APR 6 PY 2004 VL 16 IS 7 BP 1277 EP 1284 DI 10.1021/cm030425v PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 809KA UT WOS:000220634400018 ER PT J AU Shi, L Hao, Q Yu, CH Mingo, N Kong, XY Wang, ZL AF Shi, L Hao, Q Yu, CH Mingo, N Kong, XY Wang, ZL TI Thermal conductivities of individual tin dioxide nanobelts SO APPLIED PHYSICS LETTERS LA English DT Article ID SILICON NANOWIRES; NANOSTRUCTURES; OXIDES AB We have measured the thermal conductivities of a 53-nm-thick and a 64-nm-thick tin dioxide (SnO2) nanobelt using a microfabricated device in the temperature range of 80-350 K. The thermal conductivities of the nanobelts were found to be significantly lower than the bulk values, and agree with our calculation results using a full dispersion transmission function approach. Comparison between measurements and calculation suggests that phonon-boundary scattering is the primary effect determining the thermal conductivities. (C) 2004 American Institute of Physics. C1 Univ Texas, Texas Mat Inst, Dept Mech Engn, Austin, TX 78712 USA. Univ Texas, Texas Mat Inst, Ctr Nano & Mol Sci & Technol, Austin, TX 78712 USA. NASA, Ames Res Ctr, Floret Corp, Moffett Field, CA 94035 USA. Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA. RP Shi, L (reprint author), Univ Texas, Texas Mat Inst, Dept Mech Engn, Austin, TX 78712 USA. EM lishi@mail.utexas.edu RI Wang, Zhong Lin/E-2176-2011; Kong, Xiang Yang/E-1593-2012; Shi, Li/C-8123-2013; Kong, Xiangyang/F-2999-2013; Hao, Qing/B-8170-2015 OI Wang, Zhong Lin/0000-0002-5530-0380; Kong, Xiang Yang/0000-0003-0659-4084; Shi, Li/0000-0002-5401-6839; NR 18 TC 113 Z9 113 U1 3 U2 23 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 5 PY 2004 VL 84 IS 14 BP 2638 EP 2640 DI 10.1063/1.1697622 PG 3 WC Physics, Applied SC Physics GA 808RS UT WOS:000220586800056 ER PT J AU Mingo, N AF Mingo, N TI Thermoelectric figure of merit and maximum power factor in III-V semiconductor nanowires SO APPLIED PHYSICS LETTERS LA English DT Article ID QUANTUM-WELL STRUCTURES; ELECTRON TRANSPORT; GAP AB The relative contributions of electronic and lattice effects to figure of merit enhancement are studied, for nanowires made of InSb, InAs, GaAs, and InP, as a function of nanowire thickness. The main thermoelectric magnitudes are computed in the bulk and nanowire cases by the exact solution of the Boltzmann transport equation. The lattice thermal conductivity is obtained by a full dispersions transmission function approach, using interatomic potentials for the system. An upper limit to the maximum power factor is obtained for narrow thickness. InSb nanowires stand out as the best choice for thermoelectric applications among the four compounds considered, while GaAs and InP are not expected to be suitable for practical applications. (C) 2004 American Institute of Physics. C1 NASA, Ames Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Mingo, N (reprint author), NASA, Ames Ctr Nanotechnol, 229-1, Moffett Field, CA 94035 USA. EM mingo@nas.nasa.gov NR 21 TC 139 Z9 140 U1 6 U2 47 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 5 PY 2004 VL 84 IS 14 BP 2652 EP 2654 DI 10.1063/1.1695629 PG 3 WC Physics, Applied SC Physics GA 808RS UT WOS:000220586800061 ER PT J AU McGill, MJ Li, L Hart, WD Heymsfield, GM Hlavka, DL Racette, PE Tian, L Vaughan, MA Winker, DM AF McGill, MJ Li, L Hart, WD Heymsfield, GM Hlavka, DL Racette, PE Tian, L Vaughan, MA Winker, DM TI Combined lidar-radar remote sensing: Initial results from CRYSTAL-FACE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE lidar; radar; remote sensing; cirrus anvil ID TROPICAL CIRRUS; RADIATIVE IMPACTS; CLOUDS; MISSION; RETRIEVAL; PRECIPITATION; TROPOPAUSE; ALGORITHM; THIN AB In the near future, NASA plans to fly satellites carrying a two-wavelength polarization lidar and a 94-GHz cloud profiling radar in formation to provide complete global profiling of cloud and aerosol properties. The Cirrus Regional Study of Tropical Anvils and Cirrus Layers-Florida Area Cirrus Experiment (CRYSTAL-FACE) field campaign, conducted during July 2002, provided the first high-altitude collocated measurements from lidar and cloud profiling radar to simulate these spaceborne sensors. The lidar and radar provide complementary measurements with varying degrees of vertical measurement overlap within cloud layers. This paper presents initial results of the combined airborne lidar-radar measurements during CRSYTAL-FACE. A comparison of instrument sensitivity is presented within the context of particular CRYSTAL-FACE observations. It was determined that optically thin cirrus clouds are frequently missed by the radar but are easily profiled with the lidar. In contrast, optically thick clouds and convective cores quickly extinguish the lidar signal but are easily probed with the radar. Results are presented to quantify the portion of atmospheric features sensed independently by each instrument and the portion sensed simultaneously by the two instruments. To capture some element of varying atmospheric characteristics, two cases are analyzed, one with convective systems and one having synoptic cirrus and considerable clear air. The two cases show quite different results, primarily due to differences in cloud microphysics. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, GEST Ctr, NASA, Goddard Space Flight Ctr, Greenbelt, MD USA. Sci Applicat Int Corp, NASA, Langley Res Ctr, Hampton, VA 23681 USA. Sci Syst & Applicat Inc, NASA, Goddard Space Flight Ctr, Greenbelt, MD USA. RP McGill, MJ (reprint author), NASA, Goddard Space Flight Ctr, Code 912, Greenbelt, MD 20771 USA. EM matthew.j.mcgill@nasa.gov; lihua@agnes.gsfc.nasa.gov; billhart@virl.gsfc.nasa.gov; gerald.heymsfield@nasa.gov; sgdlh@virl.gsfc.nasa.gov; paul.e.racette@nasa.gov; tian@agnes.gsfc.nasa.gov; m.a.vaughan@larc.nasa.gov; david.m.winker@nasa.gov RI McGill, Matthew/D-8176-2012 NR 31 TC 44 Z9 45 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 3 PY 2004 VL 109 IS D7 AR D07203 DI 10.1029/2003JD004030 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 811AM UT WOS:000220744800001 ER PT J AU Foni, A Seal, D AF Foni, A Seal, D TI Shuttle Radar Topography Mission: an innovative approach to shuttle orbital control SO ACTA ASTRONAUTICA LA English DT Article AB On February 11, 2000, the space shuttle endeavour lifted off to tackle an ambitious mission: make the most comprehensive map ever of planet Earth. The successful 11-day Shuttle Radar Topography Mission produced the most complete terrain map of the world. Radar inteferometry was used to derive surface elevation by calculating the differences between measurements taken from slightly different locations. The payload consisted of a main antenna and an electronics package in the shuttle's payload bay with an outboard antenna at the end of a 200 f mast extended once the shuttle is in orbit. Maintaining the planned orbital profile was crucial to guarantee complete coverage of the entire land coverage with no gaps between radar swaths. Orbital maintenance was accomplished during trim maneuvers executed approximately once per day. Maneuver design was constrained significantly by the presence of the delicate 200 f mast. During the flight, seven trim bums were performed using a "fly-cast" maneuver which required a set of precisely timed pulses to minimize loading on the mast. All maneuvers were successful and kept the orbit within required limits. Extensive interaction with the Johnson Space Center Flight Dynamics Office ensured proper design and execution of the orbital control. (C) 2003 Elsevier Ltd. All rights reserved. C1 CNR, ISTI, I-56124 Pisa, Italy. NASA, Jet Prop Lab, Pasadena, CA 91109 USA. RP Foni, A (reprint author), CNR, ISTI, Area Ric CNR,Via V Moruzzi 1, I-56124 Pisa, Italy. EM alberto.foni@isti.cnr.it NR 3 TC 4 Z9 5 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD APR PY 2004 VL 54 IS 8 BP 565 EP 570 DI 10.1016/S0094-5765(03)00227-3 PG 6 WC Engineering, Aerospace SC Engineering GA 800ZM UT WOS:000220066200004 ER PT J AU Cazaux, C Naderi, F Whetsel, C Beaty, D Gershman, B Kornfeld, R Mitcheltree, B Sackheim, B AF Cazaux, C Naderi, F Whetsel, C Beaty, D Gershman, B Kornfeld, R Mitcheltree, B Sackheim, B TI The NASA/CNES Mars sample return - a status report SO ACTA ASTRONAUTICA LA English DT Article; Proceedings Paper CT 52nd International Astronautical Congress CY OCT 01-05, 2001 CL TOULOUSE, FRANCE AB The NASA's new Mars Exploration Program focuses on alignment of three strategies: Science, Technology and Management, Trade for Mars Sample Return, required technologies, consequences for 2007 missions are considered in turn. (C) 2003 Published by Elsevier Ltd. C1 Ctr Natl Etud Spatiales, F-31055 Toulouse, France. CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. NASA, Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Cazaux, C (reprint author), Ctr Natl Etud Spatiales, 18 Ave Edouard Belin, F-31055 Toulouse, France. NR 0 TC 4 Z9 4 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD APR PY 2004 VL 54 IS 8 BP 601 EP 617 DI 10.1016/j.actaastro.2003.07.001 PG 17 WC Engineering, Aerospace SC Engineering GA 800ZM UT WOS:000220066200009 ER PT J AU Hu, ZW Chu, YS Lai, B Thomas, BR Chernov, AA AF Hu, ZW Chu, YS Lai, B Thomas, BR Chernov, AA TI Diffraction and imaging study of imperfections of crystallized lysozyme with coherent X-rays SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID EGG-WHITE LYSOZYME; TETRAGONAL LYSOZYME; PROTEIN CRYSTALS; SYNCHROTRON-RADIATION; TOPOGRAPHY; PERFECTION; SOLVENT; IMPURITIES; RESOLUTION; QUALITY AB Phase-contrast X-ray diffraction imaging and high-angular-resolution diffraction combined with phase-contrast radiographic imaging were employed to characterize defects and perfection of a uniformly grown tetragonal lysozyme crystal in the symmetric Laue case. The full-width at half-maximum (FWHM) of a 440 rocking curve measured from the original crystal was similar to16.7 arcsec and imperfections including line defects, inclusions and other microdefects were observed in the diffraction images of the crystal. The observed line defects carry distinct dislocation features running approximately along the <110> growth front and have been found to originate mostly in a central growth area and occasionally in outer growth regions. Inclusions of impurities or formations of foreign particles in the central growth region are resolved in the images with high sensitivity to defects. Slow dehydration led to the broadening of a fairly symmetric 440 rocking curve by a factor of similar to2.6, which was primarily attributed to the dehydration-induced microscopic effects that are clearly shown in X-ray diffraction images. The details of the observed defects and the significant change in the revealed microstructures with drying provide insight into the nature of imperfections, nucleation and growth, and the properties of protein crystals. C1 NASA, George C Marshall Space Flight Ctr, BAE Syst, Huntsville, AL 35812 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Hu, ZW (reprint author), NASA, George C Marshall Space Flight Ctr, BAE Syst, Huntsville, AL 35812 USA. EM zhengwei.hu@msfc.nasa.gov NR 41 TC 11 Z9 11 U1 0 U2 4 PU BLACKWELL MUNKSGAARD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD APR PY 2004 VL 60 BP 621 EP 629 DI 10.1107/S0907444904000915 PN 4 PG 9 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 805LR UT WOS:000220368300001 PM 15039549 ER PT J AU Marzocca, P Silva, WA Librescu, L AF Marzocca, P Silva, WA Librescu, L TI Nonlinear open-/closed-loop aeroelastic analysis of airfoils via Volterra series SO AIAA JOURNAL LA English DT Article ID SYSTEMS; BOUNDARY; FLUTTER; PANELS AB Determination of the subcritical aeroelastic response to arbitrary time-dependent external excitation and determination of the flutter instability of open/closed-loop two-dimensional nonlinear airfoils constitute the main topics. To address these problems, Volterra series and indicial aerodynamic functions are used, and, in the same context, the pertinent aeroelastic nonlinear kernels are determined. Flutter instability predictions obtained within this approach compared with their counterparts generated via the frequency eigenvalue analysis and via experiments reveal excellent agreements. Implications of a number of important parameters characterizing the lifting surface and control law on the aeroelastic response/flutter are discussed, and pertinent conclusions are outlined. C1 Clarkson Univ, Dept Mech & Aeronaut Engn, Potsdam, NY 13699 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. RP Marzocca, P (reprint author), Clarkson Univ, Dept Mech & Aeronaut Engn, Potsdam, NY 13699 USA. NR 19 TC 31 Z9 35 U1 1 U2 8 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD APR PY 2004 VL 42 IS 4 BP 673 EP 686 DI 10.2514/1.9552 PG 14 WC Engineering, Aerospace SC Engineering GA 809TM UT WOS:000220659000001 ER PT J AU Reda, DC AF Reda, DC TI Comment on "Role of transient growth in roughness-induced transition" SO AIAA JOURNAL LA English DT Editorial Material C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Reda, DC (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 4 TC 1 Z9 1 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD APR PY 2004 VL 42 IS 4 BP 771 EP 771 DI 10.2514/1.3706 PG 1 WC Engineering, Aerospace SC Engineering GA 809TM UT WOS:000220659000011 ER PT J AU Cao, YZ Hussaini, MY Zang, TA AF Cao, YZ Hussaini, MY Zang, TA TI Exploitation of sensitivity derivatives for improving sampling methods SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA/ASME/ASCE/AHS/ASC 44th Structures Structural Dynamics and Materials Conference CY APR 07-10, 2003 CL NORFOLK, VA SP AIAA, ASME, ASCE, AHS, ASC AB Many application codes, such as finite element structural analyses and computational fluid dynamics codes, are capable of producing many sensitivity derivatives at a small fraction of the cost of the underlying analysis. A simple variance reduction method is described that exploits such inexpensive sensitivity derivatives to increase the accuracy of sampling methods. Five examples, including a finite element structural analysis of an aircraft wing, are provided that illustrate an order of magnitude improvement in accuracy for both Monte Carlo and stratified sampling schemes. C1 Florida A&M Univ, Dept Math, Tallahassee, FL 32307 USA. Florida State Univ, Sch Computat Sci & Informat Technol, Tallahassee, FL 32306 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Cao, YZ (reprint author), Florida A&M Univ, Dept Math, Tallahassee, FL 32307 USA. NR 15 TC 10 Z9 10 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD APR PY 2004 VL 42 IS 4 BP 815 EP 822 DI 10.2514/1.2820 PG 8 WC Engineering, Aerospace SC Engineering GA 809TM UT WOS:000220659000016 ER PT J AU Bol'shakov, AA Cruden, BA Mogul, R Rao, MVVS Sharma, SP Khare, BN Meyyappan, M AF Bol'shakov, AA Cruden, BA Mogul, R Rao, MVVS Sharma, SP Khare, BN Meyyappan, M TI Radio-frequency oxygen plasma as a sterilization source SO AIAA JOURNAL LA English DT Article ID INDUCTIVELY-COUPLED PLASMAS; NEAR-ULTRAVIOLET RADIATION; DEINOCOCCUS-RADIODURANS; GLOW-DISCHARGES; GAS PLASMA; PRESSURE; EMISSION; MIXTURES; DENSITY; POLYMERS AB An oxygen plasma sustained at 13.56 MHz in a standardized reactor with a planar induction coil was used for biological decontamination experiments. Optical emission, mass spectrometry, Langmuir probe, and electrical measurements were applied to detection of chemical species and ion-energy and flux analysis. These diagnostics identified a plasma-mode transition in the range of 13-67-Pa pressure and 100-330-W power to the induction coil. At higher pressure and lower power, the plasma was sustained in a dim mode (primarily by stray capacitive coupling). A primarily inductive bright mode was attained at lower pressure and higher power. The coupling mode of plasma operation was then monitored by emission spectroscopy on an analogous, scaled-down reactor for biological degradation tests. Plasmid DNA degradation efficacies were compared in both plasma modes. DNA removal was similar to25% more efficient in the inductively coupled mode than in the capacitively coupled mode at the same power. The fast degradation was attributed to synergetic mechanisms (photo- and ion-assisted etching by oxygen atoms and perhaps O-2(*) metastable molecules). Volatilization rates of the decomposition products (CO2, CO, N-2, OH, H) evolving from the microbial (Deinococcus radiodurans) and polypeptide samples exposed to the plasma were compared. A plasma sustained in Martian atmosphere is considered. C1 NASA, Ames Res Ctr, Space Technol Div, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, Ames Ctr Nanotechnol, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Bol'shakov, AA (reprint author), NASA, Ames Res Ctr, Space Technol Div, Moffett Field, CA 94035 USA. EM bcruden@mail.arc.nasa.gov; mogul@fau.edu; ssharma@mail.arc.nasa.gov; bkhare@mail.arc.nasa.gov; meyya@orbit.arc.nasa.gov RI Bol'shakov, Alexander/A-9258-2015 OI Bol'shakov, Alexander/0000-0002-6034-7079 NR 61 TC 46 Z9 48 U1 2 U2 13 PU AMER INST AERONAUTICS ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 EI 1533-385X J9 AIAA J JI AIAA J. PD APR PY 2004 VL 42 IS 4 BP 823 EP 832 DI 10.2514/1.9562 PG 10 WC Engineering, Aerospace SC Engineering GA 809TM UT WOS:000220659000017 ER PT J AU Meck, JV Waters, WW Ziegler, MG deBlock, HF Mills, PJ Robertson, D Huang, PL AF Meck, JV Waters, WW Ziegler, MG deBlock, HF Mills, PJ Robertson, D Huang, PL TI Mechanisms of postspaceflight orthostatic hypotension: low alpha(1)-adrenergic receptor responses before flight and central autonomic dysregulation postflight SO AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY LA English DT Article DE tyramine; phenylephrine; dihydroxyphenylglycol; tilt tests; arginine vasopressin ID SHORT-DURATION SPACEFLIGHT; HEAD-UP TILT; BAROREFLEX CONTROL; NERVOUS-SYSTEM; VASOPRESSIN; HUMANS; NOREPINEPHRINE; ADRENOCEPTORS; INHIBITION; ASTRONAUTS AB Although all astronauts experience symptoms of orthostatic intolerance after short-duration spaceflight, only similar to 20% actually experience presyncope during upright posture on landing day. The presyncopal group is characterized by low vascular resistance before and after flight and low norepinephrine release during orthostatic stress on landing day. Our purpose was to determine the mechanisms of the differences between presyncopal and nonpresyncopal groups. We studied 23 astronauts 10 days before launch, on landing day, and 3 days after landing. We measured pressor responses to phenylephrine injections; norepinephrine release with tyramine injections; plasma volumes; resting plasma levels of chromogranin A ( a marker of sympathetic nerve terminal release), endothelin, dihydroxyphenylglycol ( DHPG, an intracellular metabolite of norepinephrine); and lymphocyte beta(2)-adrenergic receptors. We then measured hemodynamic and neurohumoral responses to upright tilt. Astronauts were separated into two groups according to their ability to complete 10 min of upright tilt on landing day. Compared with astronauts who were not presyncopal on landing day, presyncopal astronauts had 1) significantly smaller pressor responses to phenylephrine both before and after flight; 2) significantly smaller baseline norepinephrine, but significantly greater DHPG levels, on landing day; 3) significantly greater norepinephrine release with tyramine on landing day; and 4) significantly smaller norepinephrine release, but significantly greater epinephrine and arginine vasopressin release, with upright tilt on landing day. These data suggest that the etiology of orthostatic hypotension and presyncope after spaceflight includes low alpha(1)-adrenergic receptor responsiveness before flight and a remodeling of the central nervous system during spaceflight such that sympathetic responses to baroreceptor input become impaired. C1 NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Space & Life Sci Directorate,SK, Houston, TX 77058 USA. Baylor Coll Med, Natl Space Biomed Res Inst, Houston, TX 77030 USA. Univ Calif San Diego, Dept Med, San Diego, CA 92103 USA. Albany Med Coll, Dept Surg, Albany, NY 12208 USA. Vanderbilt Univ, Dept Med, Nashville, TN 37232 USA. Vanderbilt Univ, Dept Pharmacol, Nashville, TN 37232 USA. Massachusetts Gen Hosp, Dept Cardiol, Boston, MA 02129 USA. RP Meck, JV (reprint author), NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Space & Life Sci Directorate,SK, Houston, TX 77058 USA. EM jmeck@ems.jsc.nasa.gov FU NCRR NIH HHS [M01RR-00827] NR 34 TC 73 Z9 74 U1 3 U2 6 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0363-6135 J9 AM J PHYSIOL-HEART C JI Am. J. Physiol.-Heart Circul. Physiol. PD APR 1 PY 2004 VL 286 IS 4 BP H1486 EP H1495 DI 10.1152/ajpheart.00740.2003 PG 10 WC Cardiac & Cardiovascular Systems; Physiology; Peripheral Vascular Disease SC Cardiovascular System & Cardiology; Physiology GA 802ZL UT WOS:000220201300033 PM 14670816 ER PT J AU Hart, RA Grier, JW AF Hart, RA Grier, JW TI Simulation models of harvested and zebra mussel colonized threeridge mussel populations in the upper Mississippi River SO AMERICAN MIDLAND NATURALIST LA English DT Article ID FRESH-WATER MUSSELS; WESTERN LAKE ERIE; DREISSENA-POLYMORPHA; VIABILITY ANALYSIS; UNIONID BIVALVES; SURVIVAL; CONSERVATION; INFESTATION; MANAGEMENT; IMPACT AB We simulated populations of threeridge mussels (Amblema plicata, Say, 1817) using empirically derived survival rates. Survival rates were derived from a mark-recapture study of mussels conducted in the Mississippi and Otter Tail rivers, Minnesota. The software package VORTEX was used to develop a base line population model which changed little or not at all through time. Models based on the initial base line data were constructed to simulate behaviors of A. plicata populations under various levels of mortality attributed to zebra mussel (Dreissena polymorpha, Pallas 1771) colonizations. Models were also developed that simulated varying levels of commercial harvesting of A. plicata. Sensitivity analysis revealed that A. plicata populations are most sensitive to alterations in adult survival. Adult survival is the life history stage most often impacted by both D. polymorpha colonizations and commercial harvesting. Population models simulating D. polymorpha mediated mortality revealed that population extinction was likely to occur within 50 y if survival rates remain at the levels recently measured. Models that simulated a commercial harvest of only 5% of the adult A. plicata population predicted that populations will decline by almost 50% in only 40 y. Our recommendation is that a concerted effort should be made to estimate the population size of potentially harvested populations of freshwater mussels. These estimates would allow for a more accurate estimate of what percentage of the adult mussels are actually being harvested. The population estimates would also allow for setting of quotas or limiting the number of permits for harvesters in the face of increased D. polymorpha infestations, thereby ensuring that harvested populations of mussels are not being over exploited. These modeling efforts will be useful for resource managers attempting to establish a sustainable harvest of commercially valuable mussel species which may be competing with a nonindigenous species. C1 N Dakota State Univ, Dept Biol Sci, Fargo, ND 58105 USA. USA, Corps Engineers, Waterways Expt Stn, Vicksburg, MS 39180 USA. RP Hart, RA (reprint author), Galveston Lab, Natl Marine Fisheries Serv, 4700 Ave U, Galveston, TX 77551 USA. NR 33 TC 4 Z9 4 U1 5 U2 10 PU AMER MIDLAND NATURALIST PI NOTRE DAME PA UNIV NOTRE DAME, BOX 369, ROOM 295 GLSC, NOTRE DAME, IN 46556 USA SN 0003-0031 J9 AM MIDL NAT JI Am. Midl. Nat. PD APR PY 2004 VL 151 IS 2 BP 301 EP 317 DI 10.1674/0003-0031(2004)151[0301:SMOHAZ]2.0.CO;2 PG 17 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 811RM UT WOS:000220789000010 ER PT J AU Shariff, K Ghosal, S AF Shariff, K Ghosal, S TI Peak tailing in electrophoresis due to alteration of the wall charge by adsorbed analytes a Numerical simulations and asymptotic theory SO ANALYTICA CHIMICA ACTA LA English DT Article DE capillary zone electrophoresis; dispersion; wall interactions ID ELECTROOSMOTIC FLOW; ADSORPTION; CAPILLARY AB When analytes containing cationic components, such as proteins, are separated in fused silica capillaries or micro-chips, they adsorb strongly to the negatively charged channel walls. Broadened and highly asymmetric peaks in the detector signal is symptomatic of the presence of such wall interactions. Band broadening is caused by the introduction of shear into the electroosmotic flow which leads to Taylor dispersion. The shearing flow in turn is caused by axial variations in zeta-potential due to adsorbed analytes. In this paper, numerical solutions of the coupled electro-hydrodynamic equations for fluid flow and the advection-diffusion equation for analyte concentration are presented in the limit of thin Debye layers. The simulations reproduce many of the qualitative effects of wall adsorption familiar from observation. Further, the simulation results are compared, and found to agree very well (to within a percent for characteristic values of the parameters) with a recently developed asymptotic theory. (C) 2003 Elsevier B.V. All rights reserved. C1 Northwestern Univ, Evanston, IL 60208 USA. NASA Ames Res Ctr, Stanford, CA 94305 USA. RP Ghosal, S (reprint author), Northwestern Univ, Evanston, IL 60208 USA. EM s-ghosal@northwestern.edu RI Ghosal, Sandip/A-3534-2009; Ghosal, Sandip/B-7595-2009; OI Ghosal, Sandip/0000-0001-6587-3716; Shariff, Karim/0000-0002-7256-2497 NR 17 TC 12 Z9 12 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0003-2670 J9 ANAL CHIM ACTA JI Anal. Chim. Acta PD APR 1 PY 2004 VL 507 IS 1 BP 87 EP 93 DI 10.1016/j.aca.2003.10.052 PG 7 WC Chemistry, Analytical SC Chemistry GA 778FH UT WOS:000189228400010 ER PT J AU Omoregie, EO Crumbliss, LL Bebout, BM Zehr, JP AF Omoregie, EO Crumbliss, LL Bebout, BM Zehr, JP TI Determination of nitrogen-fixing phylotypes in Lyngbya sp and Microcoleus chthonoplastes cyanobacterial mats from Guerrero Negro, Baja California, Mexico SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID MARINE MICROBIAL MAT; FIXATION GENES; N-2 FIXATION; MOLECULAR DIVERSITY; NIFH GENES; ATCC 51142; COMMUNITIES; EXPRESSION; PHOTOSYNTHESIS; ORGANIZATION AB In many environments, biological nitrogen fixation can alleviate nitrogen limitation. The high rates of N-2 fixation often observed in cyanobacterial mats suggest that N2 fixation may be an important source of N. In this study, organisms expressing nifH were identified in a Lyngbya sp.- and two Microcoleus chthonoplastes-dominated cyanobacterial mats. The pattern of nitrogenase activity was determined for the Lyngbya sp. mat and a Microcoleus chthonoplastes mat sampled directly in Guerrero Negro, Mexico. Their maximum rates were 23 and 15 mumol Of C2H4, m(-2) h(-1), respectively. The second Microcoleus mat, which was maintained in a greenhouse facility, had a maximum rate of 40 mumol Of C2H4 m(-2) h(-1). The overall diel pattern of nitrogenase activity in the three mats was similar, with the highest rates of activity occurring during the dark period. Analysis of nifH transcripts by reverse transcription-PCR revealed that several different organisms were expressing nifH during the dark period. nifH phylotypes recovered from these mats were similar to sequences from the unicellular cyanobacterial genera Halothece, Myxosarcina, and Synechocystis, the filamentous cyanobacterial genera Plectonema and Phormidium, and several bacterial nifH groups. The results of this study indicate that several different organisms, some of which were not previously known to fix nitrogen, are likely to be responsible for the observed dark-period nitrogenase activity in these cyanobacterial mats. C1 Univ Calif Santa Cruz, Dept Ocean Sci, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Inst Marine Sci, Santa Cruz, CA 95064 USA. NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. RP Zehr, JP (reprint author), Univ Calif Santa Cruz, Dept Ocean Sci, 1156 High St, Santa Cruz, CA 95064 USA. EM zehrj@ucsc.edu RI Zehr, Jonathan/B-3513-2014 OI Zehr, Jonathan/0000-0002-5691-5408 NR 51 TC 58 Z9 62 U1 2 U2 7 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD APR PY 2004 VL 70 IS 4 BP 2119 EP 2128 DI 10.1128/AEM.70.4.2119-2128.2004 PG 10 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 811SS UT WOS:000220792200028 PM 15066804 ER PT J AU Poletto, L Thomas, RJ AF Poletto, L Thomas, RJ TI Stigmatic spectrometers for extended sources: design with toroidal varied-line-space gratings SO APPLIED OPTICS LA English DT Article ID CORRECTED CONCAVE GRATINGS AB Performances are presented of three classes of imaging slit spectrometers for extended sources with aberration-corrected gratings. A general analytical expression for minimizing off-axis grating aberrations is obtained, and it is demonstrated that these aberrations are minimized when the spectrometer is operated at a magnification higher than unity. Classical designs with toroidal uniform-line-spaced (TULS) or spherical varied-line-space (SVLS) gratings are compared with a new class of designs that utilize toroidal varied-line-space (TVLS) gratings. Although TULS and SVLS designs with two stigmatic points can be designed to operate at near-unity magnification with excellent on-axis spectral and spatial resolutions, they cannot be made to satisfy the general off-axis condition, and so their off-axis performances are not optimum. On the contrary TVLS designs with two stigmatic points can be operated at almost any magnification, thus satisfying the off-axis condition perfectly. Such designs are suitable for imaging spectrometer observations that require an extended field of view. (C) 2004 Optical Society of America. C1 Univ Padua, INFM, Dept Informat Engn, I-35131 Padua, Italy. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. RP Poletto, L (reprint author), Univ Padua, INFM, Dept Informat Engn, Via Gradenigo 6-B, I-35131 Padua, Italy. EM poletto@dei.unipd.it NR 12 TC 15 Z9 15 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 2004 VL 43 IS 10 BP 2029 EP 2038 DI 10.1364/AO.43.002029 PG 10 WC Optics SC Optics GA 807HY UT WOS:000220493800007 PM 15074409 ER PT J AU Sydor, M Gould, RW Arnone, RA Haltrin, VI Goode, W AF Sydor, M Gould, RW Arnone, RA Haltrin, VI Goode, W TI Uniqueness in remote sensing of the inherent optical properties of ocean water SO APPLIED OPTICS LA English DT Article ID REFLECTANCE; ABSORPTION AB We examine the problem of uniqueness in the relationship between the remote-sensing reflectance (Rrs) and the inherent optical properties (IOPs) of ocean water. The results point to the fact that diffuse reflectance of plane irradiance from ocean water is inherently ambiguous. Furthermore, in the 400 < lambda < 750 nm region of the spectrum, Rrs(lambda) also suffers from ambiguity caused by the similarity in wavelength dependence of the coefficients of absorption by particulate matter and of absorption by colored dissolved organic matter. The absorption coefficients have overlapping exponential responses, which lead to the fact that more than one combination of IOPs can produce nearly the same Rrs spectrum. This ambiguity in absorption parameters demands that we identify the regions of the Rrs spectrum where we can isolate the effects that are due only to scattering by particulates and to absorption by pure water. The results indicate that the spectral shape of the absorption coefficient of phytoplankton, a(ph)(lambda), cannot be derived from a multiparameter fit to Rrs(lambda). However, the magnitude and the spectral dependence of the absorption coefficient can be estimated from the difference between the measured Rrs(lambda) and the best fit to Rrs(lambda) in terms of IOPs that exclude a(ph)(lambda). (C) 2004 Optical Society of America. C1 Univ Minnesota, Dept Phys, Duluth, MN 55812 USA. USN, Res Lab, Stennis Space Ctr, Stennis Space Ctr, MS 39529 USA. RP Sydor, M (reprint author), Univ Minnesota, Dept Phys, Duluth, MN 55812 USA. EM msydor@ub.d.umn.edu NR 13 TC 25 Z9 26 U1 0 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 2004 VL 43 IS 10 BP 2156 EP 2162 DI 10.1364/AO.43.002156 PG 7 WC Optics SC Optics GA 807HY UT WOS:000220493800024 PM 15074426 ER PT J AU Botero, LM Brown, KB Brumefield, S Burr, M Castenholz, RW Young, M McDermott, TR AF Botero, LM Brown, KB Brumefield, S Burr, M Castenholz, RW Young, M McDermott, TR TI Thermobaculum terrenum gen. nov., sp nov.: a non-phototrophic gram-positive thermophile representing an environmental clone group related to the Chloroflexi (green non-sulfur bacteria) and Thermomicrobia SO ARCHIVES OF MICROBIOLOGY LA English DT Article DE thermophile; green non-sulfur; chloroflexi; gram-positive; Yellowstone National Park; thermal soil ID MICROBIAL COMMUNITY STRUCTURE; FILAMENTOUS BACTERIUM; DIVERSITY; ACID; AURANTIACUS; MELILOTI AB A novel bacterium was cultivated from an extreme thermal soil in Yellowstone National Park, Wyoming, USA, that at the time of sampling had a pH of 3.9 and a temperature range of 65-92 degreesC. This organism was found to be an obligate aerobic, non-spore-forming rod, and formed pink-colored colonies. Phylogenetic analysis of the 16S rRNA gene sequence placed this organism in a clade composed entirely of environmental clones most closely related to the phyla Chloroflexi and Thermomicrobia. This bacterium stained gram-positive, contained a novel fatty-acid profile, had cell wall muramic acid content similar to that of Bacillus subtilis (significantly greater than Escherichia coli), and failed to display a lipopolysaccharide profile in SDS-polyacrylamide gels that would be indicative of a gram-negative cell wall structure. Ultrastructure examinations with transmission electron microscopy showed a thick cell wall (approximately 34 nm wide) external to a cytoplasmic membrane. The organism was not motile under the culture conditions used, and electron microscopic examination showed no evidence of flagella. Genomic G+C content was 56.4 mol%, and growth was optimal at 67 degreesC and at a pH of 7.0. This organism was able to grow heterotrophically on various carbon compounds, would use only oxygen as an electron acceptor, and its growth was not affected by light. A new species of a novel genus is proposed, with YNP1(T) (T=type strain) being Thermobaculum terrenum gen. nov., sp. nov. (16S rDNA gene GenBank accession AF391972). This bacterium has been deposited in the American Type Culture Collection (ATCC BAA-798) and the University of Oregon Culture Collection of Microorganisms from Extreme Environments (CCMEE 7001). C1 Montana State Univ, Thermal Biol Inst, Bozeman, MT 59717 USA. Sierra High Sch, Manteca, CA 95337 USA. Univ Oregon, Eugene, OR 97403 USA. NASA, Aimes Res Ctr, Astrobiol Inst, Moffett Field, CA 94035 USA. RP McDermott, TR (reprint author), Montana State Univ, Thermal Biol Inst, Bozeman, MT 59717 USA. EM timmcder@montana.edu NR 39 TC 19 Z9 21 U1 0 U2 8 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0302-8933 J9 ARCH MICROBIOL JI Arch. Microbiol. PD APR PY 2004 VL 181 IS 4 BP 269 EP 277 DI 10.1007/s00203-004-0647-7 PG 9 WC Microbiology SC Microbiology GA 805SE UT WOS:000220385200002 PM 14745485 ER PT J AU Nickerson, CA Ott, CM AF Nickerson, CA Ott, CM TI A new dimension in modeling infectious disease SO ASM NEWS LA English DT Article ID MICROGRAVITY; CULTURE AB By applying 3-dimensional cell culture techniques with the use of a rotating wall vessel bioreactor, scientists can study infectious diseases and host-pathogen interactions. The cells in the bioreactor mimic infectious cells in vivo therefore new methods of therapy, diagnosis and prevention can be developed. C1 Tulane Univ, Med Ctr, New Orleans, LA 70118 USA. NASA Johnson Space Ctr, Microbiol Lab, Houston, TX USA. RP Nickerson, CA (reprint author), Tulane Univ, Med Ctr, New Orleans, LA 70118 USA. NR 8 TC 20 Z9 20 U1 0 U2 2 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0044-7897 J9 ASM NEWS JI ASM News PD APR PY 2004 VL 70 IS 4 BP 169 EP 175 PG 7 WC Microbiology SC Microbiology GA 004EE UT WOS:000234734000014 ER PT J AU Weinberger, AJ Becklin, EE Zuckerman, B Song, I AF Weinberger, AJ Becklin, EE Zuckerman, B Song, I TI A search for warm circumstellar disks in the TW Hydrae Association SO ASTRONOMICAL JOURNAL LA English DT Article DE circumstellar matter; planetary systems : protoplanetary disks; stars : late-type; stars : pre-main-sequence ID TERRESTRIAL PLANET FORMATION; STAR HR 4796A; DUSTY DEBRIS; TAURI STARS; YOUNG STARS; DISCOVERY; EVOLUTION; HR-4796; MEMBERS; IMAGES AB A search for previously undetected optically thin disks around stars in the nearby, young, TW Hydrae Association (TWA) was conducted around 16 stars with sensitive 12 and 18 mum photometry. The survey could detect zodiacal-like dust, with temperature 200 - 300 K, at levels of L-IR/L-* = 7 x 10(-3). Possible mid-infrared excess emission from TWA 17 was detected at the 2 sigma level, but none of the other stars showed evidence for circumstellar dust. The rapid disappearance of large amounts of dust around the K- and M-type stars in this sample may mean that any planet formation in the terrestrial planet region was completed very quickly. There appears to be a bimodal distribution of dust disks in TWA, with stars having either copious or negligible warm dust. C1 Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Univ Calif Los Angeles, Div Astron & Astrophys, Los Angeles, CA 90095 USA. NASA, Astrobiol Inst, Washington, DC USA. RP Weinberger, AJ (reprint author), Carnegie Inst Washington, Dept Terr Magnetism, 5241 Broad Branch Rd NW, Washington, DC 20015 USA. EM weinberger@dtm.ciw.edu; becklin@astro.ucla.edu; ben@astro.ucla.edu; song@astro.ucla.edu OI Weinberger, Alycia/0000-0001-6654-7859 NR 35 TC 39 Z9 39 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 2004 VL 127 IS 4 BP 2246 EP 2251 DI 10.1086/382519 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 811WI UT WOS:000220801600025 ER PT J AU Cohen, M Van Winckel, H Bond, HE Gull, TR AF Cohen, M Van Winckel, H Bond, HE Gull, TR TI Hubble Space Telescope imaging of HD 44179, the Red Rectangle SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : spectroscopic; circumstellar matter; ISM : lines and bands; stars : individual (HD 44179); stars : mass loss ID BIPOLAR PROTOPLANETARY NEBULA; CLOSE BINARY; DOUBLE STARS; EGG NEBULA; CRL 2688; DISCOVERY; EMISSION; BAND; DISK; OUTFLOW AB We present Hubble Space Telescope (HST) Wide Field Planetary Camera 2 and deep ground-based images of the Red Rectangle (RR), a bipolar proto - planetary nebula associated with the post-AGB binary system HD 44179. The high-resolution HST images reveal complex new structures, many of them unique to this object. The RR nebula is dominated by a discontinuous "bicone,'' whose bright, sharp linear edges give the nebula an overall X-shaped appearance. The edges of the bicone are connected by a remarkable series of linear features elongated perpendicular to the radius vector, giving the object a ladder-like structure. The "rungs'' of the ladder structure show a quasi-periodic spacing, suggesting that they have arisen from discrete episodes of mass loss from the central star, separated by a few hundred years. The total timescale over which mass has been shed into the visible nebula is of order 14,000 yr. Outside the X-shaped bicone, parabolas curl inward, resembling wineglasses, which terminate on the bicone edges in large, limb-brightened vortices. The central object is bisected by a dark band, indicating that the star is not seen directly but is instead obscured by a surrounding opaque dust disk. C1 Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA. Katholieke Univ Leuven, Inst Sterrenkunde, B-3001 Louvain, Belgium. Space Telescope Sci Inst, Baltimore, MD 21218 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Cohen, M (reprint author), Univ Calif Berkeley, Radio Astron Lab, 601 Campbell Hall, Berkeley, CA 94720 USA. EM mcohen@astro.berkeley.edu; Hans.VanWinckel@ster.kuleuven.ac.be; bond@stsci.edu; Theodore.R.Gull@nasa.gov RI Gull, Theodore/D-2753-2012; Van Winckel, Hans/I-7863-2013 OI Gull, Theodore/0000-0002-6851-5380; Van Winckel, Hans/0000-0001-5158-9327 NR 39 TC 71 Z9 71 U1 0 U2 6 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 2004 VL 127 IS 4 BP 2362 EP 2377 DI 10.1086/382902 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 811WI UT WOS:000220801600036 ER PT J AU Doroshkevich, A Tucker, DL Allam, S Way, MJ AF Doroshkevich, A Tucker, DL Allam, S Way, MJ TI Large scale structure in the SDSS galaxy survey SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE cosmology : large-scale structure of the Universe; surveys ID DIGITAL SKY SURVEY; CAMPANAS REDSHIFT SURVEY; SPECTROSCOPIC TARGET SELECTION; EARLY DATA RELEASE; LY-ALPHA FOREST; POWER SPECTRUM; STATISTICAL CHARACTERISTICS; LOOSE GROUPS; UNIVERSE; EVOLUTION AB The Large Scale Structure in the galaxy distribution is investigated using Data Release I of the Sloan Digital Sky Survey. Using the Minimal Spanning Tree technique we have extracted sets of filaments, of wall-like structures, of galaxy groups. and of rich clusters from this unique sample. The physical properties of these structures were then measured and compared with the statistical expectations based on Zel'dovich theory. The measured characteristics of galaxy walls were found to be consistent with those for a spatially flat ACDM cosmological model with Omega(m) approximate to 0.3 and Omega(A) approximate to 0.7, and for Gaussian initial perturbations with a Harrison-Zel'dovich power spectrum. Furthermore, we found that the mass functions of groups and of unrelaxed structure elements generally fit well with the expectations from Zel'dovich theory. We also note that both groups and rich clusters tend to prefer the environments of walls, which tend to be of hi-her density, rather than the environments of filaments, which tend to be of lower density. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Theoret Astrophys Ctr, DK-2100 Copenhagen O, Denmark. Russian Acad Sci, MV Keldysh Appl Math Inst, Moscow 125047, Russia. New Mexico State Univ, Dept Astron, Las Cruces, NM 88003 USA. NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Tucker, DL (reprint author), Fermilab Natl Accelerator Lab, MS 127,POB 500, Batavia, IL 60510 USA. EM dtucker@fnal.gov RI Way, Michael/D-5254-2012; Doroshkevich, Andrey/C-3389-2014; OI Way, Michael/0000-0003-3728-0475; Tucker, Douglas/0000-0001-7211-5729 NR 45 TC 46 Z9 47 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2004 VL 418 IS 1 BP 7 EP 23 DI 10.1051/0004-6361:20031780 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 819FH UT WOS:000221299500008 ER PT J AU Schuller, P Salome, P Perrin, G Mennesson, B Niccolini, G de Laverny, P Ridgway, ST du Foresto, VC Traub, WA AF Schuller, P Salome, P Perrin, G Mennesson, B Niccolini, G de Laverny, P Ridgway, ST du Foresto, VC Traub, WA TI Are dust shell models well-suited to explain interferometric data of late-type stars in the near-infrared? SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE techniques : interferometric; radiative transfer; infrared : stars; stars : late-type; stars : circumstellar matter; stars : individual : alpha Orionis, SW Virginis; R Leonis ID GIANT BRANCH STARS; EVOLVED STARS; MASS-LOSS; TEMPORAL VARIATIONS; OPTICAL-PROPERTIES; SUPERGIANT STARS; MIRA VARIABLES; ALPHA-ORIONIS; 11 MICRONS; O CETI AB Recently available near-infrared interferometric data on late-type stars show a strong increase of diameter for asymptotic giant branch (AGB) stars between the K (2.0-2.4 mum) and L (3.4-4.1 mum) bands. Aiming at an explanation of these findings, we chose the objects alpha Orionis (Betelgeuse), SW Virginis, and R Leonis, which are of different spectral types and stages of evolution, and which are surrounded by circumstellar envelopes with different optical thicknesses. For these stars, we compared observations with spherically symmetric dust shell models. Photometric and 11 mum interferometric data were also taken into account to further constrain the models. - We find the following results. For all three AGB stars, the photosphere and dust shell model is consistent with the multi-wavelength photometric data. For alpha Orionis the model dust shell has a very small optical depth (0.0065 at 11 mum); the visibility data and model in K and L are essentially entirely photospheric with no significant contribution from the dust, and the visibility data at 11 mum show a strong dust signature which agrees with the model. For SW Virginis the model dust shell has a small optical depth (0.045 at 11 mum); in K the visibility data and model are essentially purely photospheric, in L the visibility data demand a larger object than the photosphere plus dust model allows, and at 11 mum there was no data available. For R Leonis the model dust shell has a moderate optical depth (0.1 at 11 mum); in K and L the visibility data and model situation is similar to that of SW Vir, and at 11 mum the visibility data and model are in agreement. - We conclude that AGB models comprising a photosphere and dust shell, although consistent with SED data and also interferometric data in K and at 11 mum, cannot explain the visibility data in L; an additional source of model opacity, possibly related to a gas component, is needed in L to be consistent with the visibility data. C1 Max Planck Inst Astron, D-69117 Heidelberg, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Observ Paris, LERMA, F-75014 Paris, France. Observ Paris, LESIA, F-92195 Meudon, France. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Observ Cote Azur, Dept Fresnel UMR 6528, F-06304 Nice, France. Natl Opt Astron Observ, Tucson, AZ 85726 USA. RP Schuller, P (reprint author), Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany. EM pschuller@cfa.harvard.edu NR 34 TC 14 Z9 14 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2004 VL 418 IS 1 BP 151 EP 162 DI 10.1051/0004-1161:20040051 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 819FH UT WOS:000221299500021 ER PT J AU Liu, DB Chen, L Ling, JJ You, JH Hua, XM AF Liu, DB Chen, L Ling, JJ You, JH Hua, XM TI Evolution of X-ray spectra in down-Comptonization. A comparison of the extended Kompaneets equation with Monte Carlo simulation and the Ross-McCray equation SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE scattering; radiative transfer; methods : analytical; X-rays, gamma-rays : ISM ID ACCRETION DISKS; BLACK-HOLES; RADIATION AB The original Kompaneets equation fails to describe down-Comptonization, which is the most important radiative transfer process in hard X-ray and gamma-ray astronomy, compared with up-Comptonization. In this paper, we improve our previous derivation of the extended Kompaneets equation and present it more clearly. The new equation can be used to describe a more general Comptonization process, including up- and clown-Comptonization, suitable for any case, h (ν) over bar << kT(e), h (ν) over bar >> kT(e) and h (ν) over bar similar to kT(e). The condition of the original Kompaneets equation h (ν) over bar << kT(e) is no longer necessary. Using the extended equation, we give some typical solutions in X-ray astronomy, and compare them with those of the prevailing Monte Carlo simulations and the Ross-McCray equation. The excellent consistency between the extended Kompaneets equation and Monte Carlo simulation or Ross-McCray equation confirms the correctness of our extended Kompaneets equation. The numerical solution of the extended Kompaneets equation is less expensive in terms of computational time than the Monte Carlo simulation. Another advantage of the equation method is the simplicity and the clarity in physics. The potential applications in X-ray and gamma-ray astronomy are also emphasized. C1 Shanghai Jiao Tong Univ, Dept Phys, Inst Space & Astrophys, Shanghai 200030, Peoples R China. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Liu, DB (reprint author), Shanghai Jiao Tong Univ, Dept Phys, Inst Space & Astrophys, Shanghai 200030, Peoples R China. EM dbliu@sjtu.edu.cn RI Ling, Jiajie/I-9173-2014; Liu, Dangbo/P-2224-2015 OI Ling, Jiajie/0000-0003-2982-0670; Liu, Dangbo/0000-0003-1538-592X NR 20 TC 1 Z9 1 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2004 VL 417 IS 2 BP 381 EP 389 DI 10.1051/0004-6361:20031765 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 813II UT WOS:000220900400001 ER PT J AU Miroshnichenko, AS Levato, H Bjorkman, KS Grosso, A Manset, N Men'shchikov, AB Rudy, RJ Lynch, DK Mazuk, S Venturini, CC Puetter, RC Perry, RB AF Miroshnichenko, AS Levato, H Bjorkman, KS Grosso, A Manset, N Men'shchikov, AB Rudy, RJ Lynch, DK Mazuk, S Venturini, CC Puetter, RC Perry, RB TI Properties of galactic B[e] supergiants - III. MWC 300 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : emission-line, Be; stars : individual : MWC 300; techniques : spectroscopic; circumstellar matter; radiative transfer ID HERBIG-AE/BE STARS; DIFFUSE INTERSTELLAR BANDS; INTERMEDIATE-MASS STARS; B-TYPE STARS; HIGH-RESOLUTION; SPECTRA; STELLAR; EMISSION; DUST; CATALOG AB We present the results of optical and near-IR spectroscopic and mid-IR imaging observations of the emission-line star MWC 300. Its properties and evolutionary state are still under debate (a B[e] supergiant or a Herbig Be star). For the first time we detected radial velocity variations of the photospheric lines and found a correlation between them and those of the He I lambda5876 Angstrom line. Most of the pure emission lines had stable positions for nearly 20 years. New estimates of the object's luminosity (log L/L. = 5.1 +/- 0.1), distance (D = 1.8 +/- 0.2 kpc), and systemic velocity (+26 +/- 2 km s(-1)) were derived. We found that both the circumstellar extinction in the disk-like dusty envelope and the interstellar extinction play a significant role in the attenuation of the stellar brightness. Our 2D modeling of the observed spectral energy distribution in the wavelength range from 0.3 mum to 1.3 mm suggests that the star is viewed through a gaseous-and-dusty flared disk with an opening angle of 30degrees, an inclination angle of 10degrees, an equatorial optical depth tau(V) = 3.0, and a total mass of 0.08 M.. We argue that MWC 300 is most likely a binary system, because of the similarities of its observed parameters with those of recognized B[e] binaries. C1 Univ Toledo, Dept Phys & Astron, Ritter Observ, Toledo, OH 43606 USA. Russian Acad Sci, Cent Astron Observ, St Petersburg 196140, Russia. CASLEO, RA-5400 San Juan, Argentina. Canada France Hawaii Telescope Corp, Kamuela, HI 96743 USA. Max Planck Inst Radioastron, D-53121 Bonn, Germany. St Marys Univ, Inst Computat Astrophys, Halifax, NS B3H 3C3, Canada. Aerosp Corp, Los Angeles, CA 90009 USA. Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. NASA, Langley Res Ctr, Earth & Space Sci Support Off, Hampton, VA 23681 USA. RP Miroshnichenko, AS (reprint author), Univ Toledo, Dept Phys & Astron, Ritter Observ, Toledo, OH 43606 USA. EM anatoly@physics.utoledo.edu NR 55 TC 23 Z9 23 U1 0 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 EI 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2004 VL 417 IS 2 BP 731 EP 743 DI 10.1051/0004-6361:20034181 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 813II UT WOS:000220900400032 ER PT J AU Standish, EA AF Standish, EA TI An approximation to the errors in the planetary ephemerides of the Astronomical Almanac SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE ephemerides AB Errors in the planetary coordinates of the Astronomical Almanac are approximated by comparing their fundamental ephemerides, upon which they are based, with a more recent ephemeris. JPL's DE200 provided the fundamental planetary and lunar ephemerides of the Astronomical Almanac for the years, 1984-2002, and DE405 has replaced DE200 in that role, starting in 2003. Recently, new observational measurements have become available, thereby enabling further improvements in the ephemerides, and thus, a measure of the previous errors. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Standish, EA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM ems@smyles.jpl.nasa.gov NR 13 TC 41 Z9 43 U1 1 U2 6 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2004 VL 417 IS 3 BP 1165 EP 1171 DI 10.1051/0004-6361:20035663 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 819FG UT WOS:000221299400039 ER PT J AU Kraemer, SB Ferland, GJ Gabel, JR AF Kraemer, SB Ferland, GJ Gabel, JR TI The effects of low-temperature dielectronic recombination on the relative populations of the Fe M-shell states SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic processes; galaxies : active; plasmas ID ACTIVE GALACTIC NUCLEI; X-RAY ABSORPTION; XMM-NEWTON; IONIZED-GAS; LABORATORY MEASUREMENTS; GRATING SPECTROSCOPY; PHYSICAL CONDITIONS; PHOTOIONIZED GAS; IONIZATION; COEFFICIENTS AB We examine the effects of low-temperature, or Deltan = 0, dielectronic recombination (DR) on the ionization balance of the Fe M shell (Fe IX - Fe XVI). Since Deltan = 0 rates are not available for these ions, we have derived estimates based on the existing rates for the first four ionization states of the CNO sequence and newly calculated rates for L-shell ions of third-row elements and Fe. For a range of ionization parameter and column density applicable to the intrinsic absorbers detected in ASCA, Chandra, and XMM-Newton observations of Seyfert galaxies, we generated two grids of photoionization models, with and without DR. The results show that the ionization parameter at which the population of an Fe M-shell ion peaks can increase in some cases by a factor of more than 2 when these rates are included. More importantly, there are dramatic changes in the range in ionization parameter over which individual M-shell ions contain significant fractions of the total Fe (e.g., > 10%) in the plasma. These results may explain the mismatch between the range of Fe ionization states detected in the X-ray spectra of Seyfert galaxies, identified by the energies of the M-shell unresolved transition array, and those predicted by photoionization models of the X-ray absorbers that reproduce lines of second-and third-row elements. The results suggest that care should be taken in using third-and fourth-row ions to constrain the physical conditions in photoionized X-ray plasmas until accurate DR rates are available. This underscores the importance of atomic physics in interpreting astronomical spectroscopy. C1 Catholic Univ Amer, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Univ Colorado, CASA, Boulder, CO 80309 USA. RP Kraemer, SB (reprint author), Catholic Univ Amer, Code 681, Greenbelt, MD 20771 USA. EM kraemer@yancey.gsfc.nasa.gov; gary@pa.uky.edu; jack.gabel@colorado.edu OI Ferland, Gary/0000-0003-4503-6333 NR 31 TC 40 Z9 40 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP 556 EP 561 DI 10.1086/382034 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SX UT WOS:000220522300008 ER PT J AU Dale, DA Helou, G Brauher, JR Cutri, RM Malhotra, S Beichman, CA AF Dale, DA Helou, G Brauher, JR Cutri, RM Malhotra, S Beichman, CA TI [O I] 63 micron emission from high- and low-luminosity active galactic nucleus galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (IRAS F04207-0127, IRAS F16348+7037, IRAS F16413+3954, IRAS F22231-0512); galaxies : ISM; infrared : galaxies ID ULTRALUMINOUS INFRARED GALAXIES; RADIO-LOUD QUASARS; INTERSTELLAR-MEDIUM; MOLECULAR GAS; HIGH-REDSHIFT; SPECTROSCOPY; SEARCH; VARIABILITY; BLAZARS; SAMPLE AB The Infrared Space Observatory (ISO) was used to search for a tracer of the warm and dense neutral interstellar medium, the [O I] 63.18 mum line, in four ultraluminous IRAS sources lying at redshifts between 0.6 and 1.4. While these sources are quasars, their infrared continuum emission suggests a substantial interstellar medium. No [O I] flux was detected after probing down to a 3 sigma sensitivity level sufficient for detecting line emission in starbursts with similar continuum emission. However, if the detection threshold is slightly relaxed, one target is detected with 2.7 sigma significance. For this radio-quiet quasar, there is likely a substantial dense and warm interstellar medium; the upper limits for the three radio-loud sources do not preclude the same conclusion. Using a new, uniformly processed database of the ISO extragalactic far-infrared spectroscopy observations, we show that nearby Seyfert galaxies typically have higher [O I] - to - far- infrared ratios than do normal star-forming galaxies, so the lack of strong [O I] 63 mum emission from these high-redshift ultraluminous sources cannot be attributed to their active cores. C1 Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Dale, DA (reprint author), Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. NR 61 TC 15 Z9 15 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP 565 EP 571 DI 10.1086/381959 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SX UT WOS:000220522300010 ER PT J AU Houde, M Dowell, CD Hildebrand, RH Dotson, JL Vaillancourt, JE Phillips, TG Peng, RS Bastien, P AF Houde, M Dowell, CD Hildebrand, RH Dotson, JL Vaillancourt, JE Phillips, TG Peng, RS Bastien, P TI Tracing the magnetic field in Orion A SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; ISM : individual (Orion); ISM : magnetic fields; polarization; radio lines : ISM ID MOLECULAR ION SPECTRA; STAR-FORMATION; CLOUDS; POLARIZATION; ALIGNMENT; OMC-3; DUST; FILAMENT; EMISSION; OUTFLOWS AB We use extensive 350 mum polarimetry and continuum maps obtained with the Hertz polarimeter and SHARC II (Submillimeter High Angular Resolution Camera II) along with HCN and HCO(+) spectroscopic data to trace the orientation of the magnetic field in the Orion A star-forming region. Using the polarimetry data, we find that the direction of the projection of the magnetic field in the plane of the sky relative to the orientation of the integral-shaped filament varies considerably as one moves from north to south. While in IRAS 05327-0457 and OMC-3 MMS 1-6 the projection of the field is primarily perpendicular to the filament, it becomes better aligned with it at OMC-3 MMS 8-9, and well aligned with it at OMC-2 FIR 6. The OMC-2 FIR 4 cloud, located between the last two clouds, is a peculiar object in which we find almost no polarization. There is a relatively sharp boundary within its core where two adjacent regions exhibiting differing polarization angles merge. The projected angle of the field is more complicated in OMC-1, where it exhibits smooth variations in its orientation across the face of this massive complex. We also note that while the relative orientation of the projected angle of the magnetic field to the filament varies significantly in the OMC-3 and OMC-2 regions, its orientation relative to a fixed position on the sky shows far greater stability. This suggests that the orientation of the field is perhaps relatively unaffected by the mass condensation present in these parts of the molecular cloud. By combining the polarimetry and spectroscopic data, we were able to measure a set of average values for the inclination angle of the magnetic field relative to the line of sight. We find that the field is oriented quite close to the plane of the sky in most places. More precisely, the inclination of the magnetic field is approximate to73degrees around OMC-3 MMS 6, approximate to74degrees at OMC-3 MMS 8-9, approximate to80 at OMC-2 FIR 4, approximate to65degrees in the northeastern part of OMC-1, and approximate to49degrees in the Orion bar. The small difference in the inclination of the field between OMC-3 and OMC-2 seems to strengthen the idea that the orientation of the magnetic field is relatively unaffected by the agglomeration of matter located in these regions. We also present polarimetry data for the OMC-4 region located some 13' south of OMC-1. C1 Caltech Submillimeter Observ, Hilo, HI 96720 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Pasadena, CA 91125 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Chicago, Dept Phys, Chicago, IL 60637 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Montreal, Dept Phys, Montreal, PQ H3C 3J7, Canada. RP Houde, M (reprint author), Caltech Submillimeter Observ, 111 Nowelo St, Hilo, HI 96720 USA. EM houde@submm.caltech.edu OI Vaillancourt, John/0000-0001-8916-1828 NR 35 TC 72 Z9 73 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP 717 EP 740 DI 10.1086/382067 PN 1 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SX UT WOS:000220522300025 ER PT J AU Gonthier, PL Van Guilder, R Harding, AK AF Gonthier, PL Van Guilder, R Harding, AK TI Role of beam geometry in population statistics and pulse profiles of radio and gamma-ray pulsars SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : theory; magnetic fields; pulsars : general radiation; mechanisms : nonthermal; stars : neutron ID VELOCITY DISTRIBUTION; PAIR FORMATION; EGRET SOURCES; X-RAY; EMISSION; DISCOVERY; MODEL; ACCELERATION; EVOLUTION; SPECTRA AB We present results of a pulsar population synthesis study that incorporates a number of recent developments and some significant improvements over our previous study. We have included the results of the Parkes multibeam pulsar survey in our select group of nine radio surveys, doubling our sample of radio pulsars. More realistic geometries for the radio and gamma-ray beams are included in our Monte Carlo computer code, which simulates the characteristics of the Galactic population of radio and gamma-ray pulsars. We adopted with some modifications the radio-beam geometry of Arzoumanian, Chernoff, and Cordes. For the gamma-ray beam, we have assumed the slot gap geometry described in the work of Muslimov and Harding. To account for the shape of the distribution of radio pulsars in the (P)over dot-P diagram, we continue to find that decay of the magnetic field on a timescale of 2.8 Myr is needed. With all nine surveys, our model predicts that EGRET should have seen seven radio-quiet (below the sensitivity of these radio surveys) and 19 radio-loud gamma-ray pulsars. AGILE (nominal sensitivity map) is expected to detect 13 radio-quiet and 37 radio-loud gamma-ray pulsars, while GLAST, with greater sensitivity, is expected to detect 276 radio-quiet and 344 radio-loud gamma-ray pulsars. When the Parkes multibeam pulsar survey is excluded, the ratio of radio-loud to radio-quiet gamma-ray pulsars decreases, especially for GLAST. The decrease for EGRET is 45%, implying that some fraction of EGRET unidentified sources are radio-loud gamma-ray pulsars. In the radio geometry adopted, short-period pulsars are core dominated. Unlike the EGRET gamma-ray pulsars, our model predicts that when two gamma-ray peaks appear in the pulse profile, a dominant radio core peak appears in between the gamma-ray peaks. Our findings suggest that further improvements are required in describing both the radio and gamma-ray geometries. C1 Hope Coll, Dept Phys & Engn, Holland, MI 49423 USA. Univ Colorado, Dept Phys, Denver, CO 80217 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Hope Coll, Dept Phys & Engn, 27 Graves Pl, Holland, MI 49423 USA. EM gonthier@hope.edu; rvanguilder@usa.net; harding@twinkie.gsfc.nasa.gov RI Harding, Alice/D-3160-2012 NR 48 TC 53 Z9 53 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP 775 EP 790 DI 10.1086/382070 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SX UT WOS:000220522300029 ER PT J AU Matsuura, M Zijlstra, AA Molster, FJ Hony, S Waters, LBFM Kemper, F Bowey, JE Chihara, H Koike, C Keller, LP AF Matsuura, M Zijlstra, AA Molster, FJ Hony, S Waters, LBFM Kemper, F Bowey, JE Chihara, H Koike, C Keller, LP TI Polycyclic aromatic hydrocarbons and crystalline silicates in the bipolar post-asymptotic giant branch star IRAS 16279-4757 SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; dust, extinction; infrared : stars; stars : AGB and post-AGB ID EVOLVED STARS; RED RECTANGLE; OH/IR STARS; DUST; NEBULA; ENVIRONMENTS; SPECTRUM; INTERSTELLAR; FEATURES; OBJECTS AB IRAS 16279-4757 belongs to a group of post-asymptotic giant branch (post-AGB) stars showing both polycyclic aromatic hydrocarbon (PAH) bands and crystalline silicates. We present mid-infrared images that resolve the object for the first time. The morphology is similar to that of the "Red Rectangle" (HD 44179), the prototype object with PAHs and crystalline silicates. A two-component model and images suggest a dense oxygen-rich torus, an inner, low-density, carbon-rich region, and a carbon-rich bipolar outflow. The PAH bands are enhanced at the outflow, while the continuum emission is concentrated toward the center. Our findings support the suggestion that mixed chemistry and morphology are closely related. We discuss the Infrared Space Observatory Short-Wavelength Spectrometer (ISO SWS) spectra of IRAS 16279-4757. Several bands in the ISO SWS spectrum show a match with anorthite: this would be the first detection of this mineral outside the solar system. Compared to HD 44179, the shapes of PAH bands are closer to those of planetary nebulae, possibly related to a population of small PAHs present in HD 44179 but absent around IRAS 16279-4757. Detailed examination of the spectra shows the individual character of these two objects. The comparison suggests that the torus found in IRAS 16279-4757 may have formed more recently than that in HD 44179. C1 Univ Manchester, Inst Sci & Technol, Dept Phys, Manchester M60 1QD, Lancs, England. European Space Agcy, European Space Res & Technol Ctr, NL-2200 AG Noordwijk, Netherlands. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Katholieke Univ Leuven, Inst Sterrenkunde, B-3001 Heverlee, Belgium. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. UCL, Dept Phys & Astron, London WC1E 6BT, England. Kyoto Pharmaceut Univ, Kyoto 6078412, Japan. Osaka Univ, Dept Earth & Space Sci, Osaka 5600043, Japan. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Matsuura, M (reprint author), Univ Manchester, Inst Sci & Technol, Dept Phys, POB 88, Manchester M60 1QD, Lancs, England. RI Kemper, Francisca/D-8688-2011 OI Kemper, Francisca/0000-0003-2743-8240 NR 29 TC 26 Z9 26 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP 791 EP 799 DI 10.1086/382064 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SX UT WOS:000220522300030 ER PT J AU Mainzer, AK McLean, IS Sievers, JL Young, ET AF Mainzer, AK McLean, IS Sievers, JL Young, ET TI Using narrowband photometry to classify stars and brown dwarfs SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; stars : formation; stars : low-mass, brown dwarfs; stars : pre-main-sequence ID ALL-SKY SURVEY; T-DWARFS; SPECTRAL CLASSIFICATION; DISCOVERY; 2MASS AB We present a new system of narrowband filters in the near-infrared that can be used to classify stars and brown dwarfs. This set of four filters, spanning the H band, can be used to identify molecular features unique to brown dwarfs, such as H2O and CH4. The four filters are centered at 1.495 mum (H2O), 1.595 mum (continuum), 1.66 mum (CH4), and 1.75 mum (H2O). Using two H2O filters allows us to solve for the reddening of individual objects. This can be accomplished by constructing a color-color-color cube and rotating it until the reddening vector disappears. We created a model of predicted color-color-color values for different spectral types by integrating filter bandpass data with the spectra of known stars and brown dwarfs. We validated this model by making photometric measurements of seven known L and T dwarfs, ranging from L1 to T7.5. The photometric measurements agree with the model to within +/-0.1 mag, allowing us to create spectral indexes for different spectral types. We can classify A through early M stars to within +/-2 spectral types, late-type M and L dwarfs to within +/-0.3 spectral types, and T dwarfs to within +/-0.1 spectral types (1 sigma). Thus, we can distinguish between a T1 and a T3 dwarf. The four physical bands can be converted into two reddening-free indexes mu(1) and mu(2) and an extinction AV for the individual objects. This technique, which is equivalent to extremely low resolution spectroscopy, can be used to survey large areas to provide rough spectral classifications for all the stars in the area, ranging down to the coolest brown dwarfs. It should prove particularly useful in young clusters where reddening can be high. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Mainzer, AK (reprint author), Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. EM amainzer@jpl.nasa.gov; mclean@astro.ucla.edu; sievers@cita.utoronto.ca; eyoung@as.arizona.edu OI Sievers, Jonathan/0000-0001-6903-5074 NR 22 TC 9 Z9 9 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP 832 EP 841 DI 10.1086/382020 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SX UT WOS:000220522300034 ER PT J AU McIintosh, SW Smillie, DG AF McIintosh, SW Smillie, DG TI Characteristic scales of chromospheric oscillation wave packets SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : atmospheric motions; Sun : chromosphere; Sun : magnetic fields; Sun : transition region; Sun : UV radiation ID MAGNETIC-FLUX CONCENTRATIONS; CELL-NETWORK DISTINCTIONS; SOLAR ATMOSPHERE; TRANSITION REGION; PHOTOSPHERIC MOTION; DYNAMICS; TRACE AB We use wavelet transforms to study the characteristic time scales of chromospheric oscillation "wave packets" that are observed in Transition Region and Coronal Explorer (TRACE) ultraviolet continuum image time series. Using several data sets, we investigate the statistical, spatial, and temporal intermittence of the number, duration, mean frequency, and delay ("wait time") between wave packets in the time series data. Further, we demonstrate that these characteristic values are consistent with newly developed pictures of the wave-mode suppression and conversion by the chromospheric magnetic "canopy." We propose that wavelet analysis may be fruitfully used in diagnosing the structure of the chromosphere and in identifying chromospheric oscillation wave packets temporally and spatially with their photospheric sources. C1 Univ Space Res Assoc, Cooperat Program Space Sci, Seabrook, MD 20706 USA. NASA, Astron & Solar Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP McIintosh, SW (reprint author), Univ Space Res Assoc, Cooperat Program Space Sci, Seabrook, MD 20706 USA. EM scott@grace.nascom.nasa.gov; darren.smillie@imperial.ac.uk NR 31 TC 12 Z9 12 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP 924 EP 935 DI 10.1086/382127 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SX UT WOS:000220522300043 ER PT J AU Bigazzi, A Ruzmaikin, A AF Bigazzi, A Ruzmaikin, A TI The Sun's preferred longitudes and the coupling of magnetic dynamo modes SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; Sun : magnetic fields ID SOLAR CONVECTION ZONE; DEEP MERIDIONAL FLOW; EMERGING FLUX TUBES; DIFFERENTIAL ROTATION; ACTIVE LONGITUDES; CYCLE 23; FIELD; CIRCULATION; REGIONS; INSTABILITY AB Observations show that solar activity is distributed nonaxisymmetrically, concentrating at "preferred longitudes." This indicates the important role of nonaxisymmetric magnetic fields in the origin of solar activity. We investigate the generation of the nonaxisymmetric fields and their coupling with the axisymmetric solar magnetic field. Our kinematic generation (dynamo) model operating in a sphere includes a model of solar differential rotation, as obtained by inversion of helioseismic data, modeled distributions of the turbulent resistivity, nonaxisymmetric mean helicity, and meridional circulation in the convection zone. We find that (1) the nonaxisymmetric modes are localized near the base of the convection zone, where the formation of active regions starts, and at latitudes around 30degrees; (2) the coupling of nonaxisymmetric and axisymmetric modes causes the nonaxisymmetric mode to follow the solar cycle; the phase relations between the modes are found; and (3) the rate of rotation of the first nonaxisymmetric mode is close to that determined in interplanetary space. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 50 TC 27 Z9 29 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP 944 EP 959 DI 10.1086/381932 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SX UT WOS:000220522300045 ER PT J AU Georganopoulos, M Kazanas, D AF Georganopoulos, M Kazanas, D TI Witnessing the gradual slowdown of powerful extragalactic jets: The X-ray-optical-radio connection SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; quasars : general; radiation mechanisms : nonthermal; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; PARTICLE-ACCELERATION; QUASAR GB-1508+5714; CHANDRA; RADIATION; COMPTON; Z=4.3; SPECTRUM; EMISSION; 3C-273 AB A puzzling feature of the Chandra-detected quasar jets is that their X-ray emission decreases faster along the jet than their radio emission, resulting in an outward-increasing radio-to-X-ray ratio. In some sources this behavior is so extreme that the radio emission peak is located clearly downstream of that of the X-rays. This is a rather unanticipated behavior given that the inverse Compton nature of the X-rays and the synchrotron radio emission are attributed to roughly the same electrons of the jet's nonthermal electron distribution. In this Letter we show that this morphological behavior can result from the gradual deceleration of a relativistic flow and that the offsets in peak emission at different wavelengths carry the imprint of this deceleration. This notion is consistent with another recent finding, namely, that the jets feeding the terminal hot spots of powerful radio galaxies and quasars are still relativistic with Lorentz factors Gamma similar to 2-3. The picture of the kinematics of powerful jets emerging from these considerations is that they remain relativistic as they gradually decelerate from kiloparsec scales to the hot spots, where, in a final collision with the intergalactic medium, they slow down rapidly to the subrelativistic velocities of the hot spot advance speed. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Georganopoulos, M (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Code 661, Greenbelt, MD 20771 USA. EM markos@milkyway.gsfc.nasa.gov; demos.kazanas-1@nasa.gov NR 23 TC 42 Z9 42 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP L81 EP L84 DI 10.1086/386339 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SY UT WOS:000220522400003 ER PT J AU Gloeckler, G Allegrini, F Elliott, HA McComas, DJ Schwadron, NA Geiss, J von Steiger, R Jones, GH AF Gloeckler, G Allegrini, F Elliott, HA McComas, DJ Schwadron, NA Geiss, J von Steiger, R Jones, GH TI Cometary ions trapped in a coronal mass ejection SO ASTROPHYSICAL JOURNAL LA English DT Article DE comets : general; interplanetary medium ID GIACOBINI-ZINNER; PICKUP IONS; HALLEY; TAIL AB Ion tails of comets are known to extend radially away from the Sun over very large distances. Crossing these tails by spacecraft not specifically targeted to intercept them was believed to be extremely improbable, since that requires precise angular alignment of the spacecraft with a comet. We report here the fortuitous detection of cometary ions at large angular separation far from the comet. To explain this unexpected discovery, we conclude that these ions were ducted laterally along magnetic fields that were randomly distorted by a coronal mass ejection and that such transport increases the probability of an unplanned detection of comets. C1 Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. SW Res Inst, San Antonio, TX 78228 USA. Int Space Sci Inst, CH-3012 Bern, Switzerland. CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA. RP Gloeckler, G (reprint author), Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. EM gg10@umail.umd.edu RI Von Steiger, Rudolf/F-6822-2011; Jones, Geraint/C-1682-2008 OI Jones, Geraint/0000-0002-5859-1136; Von Steiger, Rudolf/0000-0002-3350-0023; NR 24 TC 17 Z9 17 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2004 VL 604 IS 2 BP L121 EP L124 DI 10.1086/383524 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SY UT WOS:000220522400013 ER PT J AU Strickland, DK Heckman, TM Colbert, EJM Hoopes, CG Weaver, KA AF Strickland, DK Heckman, TM Colbert, EJM Hoopes, CG Weaver, KA TI A high spatial resolution X-ray and H alpha study of hot gas in the halos of star-forming disk galaxies. I. Spatial and spectral properties of the diffuse X-ray emission SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Review DE galaxies : halos; galaxies : individual (NGC 253, NGC 891, NGC 1482, NGC 3034, NGC 3073, NGC 3079, NGC 3628, NGC 4244, NGC 4631, NGC 4945, NGC 6503); galaxies : starburst; ISM : bubbles; ISM : jets and outflows; X-rays : galaxies ID EDGE-ON GALAXIES; RADIO-CONTINUUM EMISSION; SCULPTOR GROUP GALAXIES; NEARBY SPIRAL GALAXIES; ACTIVE GALACTIC NUCLEI; NEUTRAL HYDROGEN OBSERVATIONS; SEYFERT-STARBURST CONNECTION; ROSAT PSPC OBSERVATIONS; HUBBLE-SPACE-TELESCOPE; LARGE-SCALE OUTFLOWS AB We present arcsecond resolution Chandra X-ray and ground-based optical Halpha imaging of a sample of 10 edge-on star-forming disk galaxies (seven starburst and three "normal'' spiral galaxies), a sample that covers the full range of star formation intensity found in disk galaxies. The X-ray observations make use of the unprecedented spatial resolution of the Chandra X-ray observatory to more robustly than before remove X-ray emission from point sources and hence obtain the X-ray properties of the diffuse thermal emission alone. We have combined the X-ray observations with existing, comparable-resolution, ground-based Halpha and R-band imaging and present a mini-atlas of images on a common spatial and surface brightness scale to aid cross-comparison. In general, the morphology of the extraplanar diffuse X-ray emission is very similar to the extraplanar Halpha filaments and arcs, on both small and large scales (scales of tens of parsecs and kiloparsecs, respectively). The most spectacular cases of this are found in NGC 1482 (for which we provide the first published X-ray observation) and NGC 3079. We provide a variety of quantitative measures of how the spectral hardness and surface brightness of the diffuse X-ray emission varies with increasing height z above the plane of each galaxy. Of the eight galaxies in which diffuse X-ray emitting halos are found (the starbursts and the normal spiral NGC 891), significant spatial variation in the spectral properties of the extraplanar emission (\z\ greater than or equal to 2 kpc) is only found in two cases: NGC 3628 and NGC 4631. In general, the vertical distribution of the halo-region X-ray surface brightness is best described as an exponential, with the observed scale heights of the sample galaxies lying in the range H(eff) similar to 2-4 kpc. The presence of extraplanar X-ray emission is always associated with the presence of extraplanar optical line emission of similar vertical extent. No X-ray emission was detected from the halos of the two low-mass normal spiral galaxies NGC 6503 and NGC 4244. Active galactic nuclei, where present, appear to play no role in powering or shaping the outflows from the starburst galaxies in this sample. The Chandra ACIS X-ray spectra of extraplanar emission from all these galaxies can be fitted with a common two-temperature spectral model with an enhanced alpha-to-iron element ratio. This is consistent with the origin of the X-ray emitting gas being either metal-enriched merged SN ejecta or shock-heated ambient halo or disk material with moderate levels of metal depletion onto dust. Our favored model is that SN feedback in the disks of star-forming galaxies create, via blow-out and venting of hot gas from the disk, tenuous exponential atmospheres of density scale height H(g) similar to 4-8 kpc. The soft thermal X-ray emission observed in the halos of the starburst galaxies is either this preexisting halo medium, which has been swept up and shock-heated by the starburst-driven wind, or wind material compressed near the walls of the outflow by reverse shocks within the wind. In either case, the X-ray emission provides us with a powerful probe of the properties of gaseous halos around star-forming disk galaxies. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Strickland, DK (reprint author), Johns Hopkins Univ, Dept Phys & Astron, 3400 N Charles St, Baltimore, MD 21218 USA. NR 239 TC 220 Z9 220 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD APR PY 2004 VL 151 IS 2 BP 193 EP 236 DI 10.1086/382214 PG 44 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SW UT WOS:000220522200002 ER PT J AU Temi, P Brighenti, F Mathews, WG Bregman, JD AF Temi, P Brighenti, F Mathews, WG Bregman, JD TI Cold dust in early-type galaxies. I. Observations SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE dust, extinction; galaxies : elliptical and lenticular, cD; galaxies : ISM; infrared : galaxies; infrared : ISM ID NEUTRAL HYDROGEN OBSERVATIONS; VIRGO CLUSTER GALAXIES; AMES ELLIPTIC GALAXIES; FAR-INFRARED EMISSION; INTERSTELLAR MATTER; SPIRAL GALAXIES; MASS-LOSS; H-I; GAS; SAMPLE AB We describe far-infrared observations of early-type galaxies selected from the Infrared Space Observatory (ISO) archive. This rather inhomogeneous sample includes 39 giant elliptical galaxies and 14 S0 (or later) galaxies. These galaxies were observed with the array photometer PHOT on-board the ISO satellite using a variety of different observing modes-sparse maps, mini-maps, oversampled maps, and single pointings-each of which requires different and often rather elaborate photometric reduction procedures. The ISO background data agree well with the COBE-DIRBE results to which we have renormalized our calibrations. As a further check, the ISO fluxes from galaxies at 60 and 100 mum agree very well with those previously observed with IRAS at these wavelengths. The spatial resolution of ISO is several times greater than that of IRAS, and the ISO observations extend out to 200 mum, which views a significantly greater mass of colder dust not assessable to IRAS. Most of the galaxies are essentially point sources at ISO resolution, but a few are clearly extended at FIR wavelengths with image sizes that increase with FIR wavelength. The integrated far-infrared luminosities do not correlate with optical luminosities, suggesting that the dust may have an external, merger-related origin. In general, the far-infrared spectral energy distributions can be modeled with dust at two temperatures, similar to43 and similar to20 K, which probably represent limits of a continuous range of temperatures. The colder dust component dominates the total mass of dust, 10(6)-10(7) M., which is typically more than 10 times larger than the dust masses previously estimated for the same galaxies using IRAS observations. For S0 galaxies we find that the optically normalized far-infrared luminosity L(FIR)/L(B) correlates strongly with the mid-infrared luminosity L(15) (mum)/L(B), but that correlation is weaker for elliptical galaxies. C1 NASA, Ames Res Ctr, Astrophys Branch, Moffett Field, CA 94035 USA. Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy. Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Board Studies Astron & Astrophys, Santa Cruz, CA 95064 USA. RP Temi, P (reprint author), NASA, Ames Res Ctr, Astrophys Branch, MS 245-6, Moffett Field, CA 94035 USA. NR 71 TC 77 Z9 78 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD APR PY 2004 VL 151 IS 2 BP 237 EP 269 DI 10.1086/381963 PG 33 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807SW UT WOS:000220522200003 ER PT J AU Craig, P Parker, D Brainard, R Rice, M Balazs, G AF Craig, P Parker, D Brainard, R Rice, M Balazs, G TI Migrations of green turtles in the central South Pacific SO BIOLOGICAL CONSERVATION LA English DT Article DE sea turtle; Chelonia mydas; migration; South Pacific; American Samoa; Fiji ID CHELONIA-MYDAS; ISLAND AB Migrations of seven post-nesting green turtles at Rose Atoll (American Samoa) were tracked by satellite transmitters in 1993-1995. Most turtles migrated 1600 km to foraging areas in Fiji and occupied home ranges averaging 27 km(2). Additional tag recaptures from other studies indicate a common pattern of turtle movement in the central South Pacific region. In total, the 26 recaptures of primarily post-nesting turtles from French Polynesia, American Samoa, and Cook Islands showed a similar course of direction and destination: 96% migrated westward after nesting, with 58% going specifically to Fiji. We propose that this pattern reflects the lower availability of turtle food east of Fiji where most islands are small, steep and have limited areas suitable for seagrass or algal growth. In contrast, Fiji's extensive pastures of seagrass and algae appear to be a significant resource for many green turtles in the region. These turtles apparently spend most of their adult life in Fijian waters, taking only brief migrations to other islands to nest. (C) 2003 Elsevier Ltd. All rights reserved. C1 Natl Pk Amer Samoa, Pago Pago, AS 96799 USA. Hawaii Preparatory Acad, Kamuela, HI 96743 USA. Natl Marine Fisheries Serv, Pacific Isl Fisheries Sci Ctr, Honolulu, HI 96822 USA. Joint Inst Marine & Atmospher Res, La Jolla, CA 92037 USA. RP Craig, P (reprint author), Natl Pk Amer Samoa, Pago Pago, AS 96799 USA. EM peter_craig@nps.gov NR 31 TC 17 Z9 24 U1 4 U2 15 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0006-3207 J9 BIOL CONSERV JI Biol. Conserv. PD APR PY 2004 VL 116 IS 3 BP 433 EP 438 DI 10.1016/S0006-3207(03)00217-9 PG 6 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 800GQ UT WOS:000220017300013 ER PT J AU Sun, LP Vandendriesch, D AF Sun, LP Vandendriesch, D TI NASA's Cell Culture Unit SO BIOPHARM INTERNATIONAL-THE APPLIED TECHNOLOGIES OF BIOPHARMACEUTICAL DEVELOPMENT LA English DT Article C1 Payload Syst, Cambridge, MA 02142 USA. NASA, Ames Res Ctr, CCU, Moffett Field, CA 94305 USA. RP Sun, LP (reprint author), Payload Syst, 247 3rd St, Cambridge, MA 02142 USA. EM sun@payload.com; dvandendriesche@mail.arc.nasa.gov NR 3 TC 0 Z9 0 U1 0 U2 0 PU ADVANSTAR COMMUNICATIONS PI DULUTH PA 131 W FIRST ST, DULUTH, MN 55802 USA SN 1542-166X J9 BIOPHARM INT JI Biopharm. Int. PD APR PY 2004 VL 17 IS 4 BP 48 EP + PG 5 WC Biotechnology & Applied Microbiology; Pharmacology & Pharmacy SC Biotechnology & Applied Microbiology; Pharmacology & Pharmacy GA 811OD UT WOS:000220780300007 ER PT J AU Remsberg, E Deaver, L AF Remsberg, E Deaver, L TI Changes in middle atmosphere temperature SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Editorial Material C1 NASA, LRC, Hampton, VA 23665 USA. RP Remsberg, E (reprint author), NASA, LRC, Hampton, VA 23665 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD APR PY 2004 VL 85 IS 4 BP 499 EP 500 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 817FA UT WOS:000221162200008 ER PT J AU Smith, SM Dillon, EL DeKerlegand, DE Davis-Street, JE AF Smith, SM Dillon, EL DeKerlegand, DE Davis-Street, JE TI Variability of collagen crosslinks: Impact of sample collection period SO CALCIFIED TISSUE INTERNATIONAL LA English DT Article DE N-telopeptide; day-to-day variability; pyridinoline; deoxypyridinoline; bone markers ID BONE-RESORPTION MARKERS; URINARY-EXCRETION; BIOCHEMICAL MARKERS; SPACE-FLIGHT AB Because of the variability of collagen crosslinks, their use as markers for bone resorption is often criticized. We hypothesized that the variability could be reduced by collecting urine for 24 hours (or longer) instead of using single voids, and by not normalizing to creatinine. Urine samples were collected from 22 healthy subjects during two or more 24-hour periods. Each 24-hour pool and each 2nd void of the day were analyzed for N-telopeptide (NTX), pyridinium (PYD), and deoxypyridinoline (DPD) crosslinks. Data were analyzed by using linear regression. For NTX, R-2 for the two, 2nd-void samples (n=38) was 0.55, whereas R-2 for the two 24-hour pools was 0.51 or 0.52, expressed per day or per creatinine. For PYD and DPD, R-2 for the 2nd-void samples was 0.26 and 0.18, R-2 for the 24-hour pools expressed per day was 0.58 and 0.74, and R-2 for the 24-hour pools expressed per creatinine was 0.65 and 0.76, respectively. Regression of the 2nd void and the corresponding 24-hour pool, expressed per day, yielded R-2=0.19, 0.19, and 0.08, for NTX, PYD, and DPD, respectively (n=76 each). For the 2nd-void sample and its corresponding 24-hour pool, expressed per creatinine, R-2=0.24, 0.33, and 0.08, respectively. In a separate study, the coefficient of variation for NTX was reduced (P<0.05) when data from more than one 24-hour collection were combined. Thus, the variability inherent in crosslink determinations can be reduced by collecting urine for longer periods. In research studies, the high variability of single-void collections, compounded by creatinine normalization, may alter or obscure findings. C1 NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. Enterprise Advisory Serv Inc, Houston, TX 77058 USA. RP Smith, SM (reprint author), NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. EM scott.m.smith@nasa.gov RI Dillon, Edgar/B-2495-2008 NR 14 TC 11 Z9 11 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0171-967X J9 CALCIFIED TISSUE INT JI Calcif. Tissue Int. PD APR PY 2004 VL 74 IS 4 BP 336 EP 341 DI 10.1007/s00223-003-0149-7 PG 6 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 810HL UT WOS:000220695300005 PM 15255070 ER PT J AU Biennier, L Salama, F Gupta, M O'Keefe, A AF Biennier, L Salama, F Gupta, M O'Keefe, A TI Multiplex integrated cavity output spectroscopy of cold PAH cations SO CHEMICAL PHYSICS LETTERS LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; DIFFUSE INTERSTELLAR BANDS; ENHANCED ABSORPTION-SPECTROSCOPY; GAS-PHASE; INFRARED-SPECTROSCOPY; MOLECULES; CARRIERS; COMPLEX; PYRENE AB Multiplex Integrated Cavity Output Spectroscopy (MICOS) is a new cavity-enhanced absorption method that allows the use of broadband dye nanosecond pulsed laser sources and offers a sensitivity equivalent to CRDS. MICOS has been coupled to a pulsed discharge slit nozzle to measure the spectra of the cold naphthalene (C10H8+), acenaplithene (C12H10divided by) and pyrene (C16H10divided by) cations in the gas phase. A femtosecond relaxation timescale is measured for the D-5 <-- D-0 (0-0) transition of C16H10divided by. Spectra recorded at high plasma energies also show evidence of fragmentation. The CH radical is observed and carbon nanoparticles are generated in the plasma. Published by Elsevier B.V. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. Los Gatos Res, Mountain View, CA 94041 USA. RP Biennier, L (reprint author), NASA, Ames Res Ctr, Div Space Sci, Mail Stop 245-6, Moffett Field, CA 94035 USA. EM ludovic.biennier@univ-rennes1.fr RI Salama, Farid/A-8787-2009; Biennier, Ludovic/O-1618-2014 OI Salama, Farid/0000-0002-6064-4401; NR 27 TC 39 Z9 39 U1 1 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD APR 1 PY 2004 VL 387 IS 4-6 BP 287 EP 294 DI 10.1016/j.cplett.2004.02.025 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 809EO UT WOS:000220620200016 ER PT J AU Chao, WC Chen, B AF Chao, WC Chen, B TI Single and double ITCZ in an aqua-planet model with constant sea surface temperature and solar angle SO CLIMATE DYNAMICS LA English DT Article ID TROPICAL INTRASEASONAL OSCILLATION; NEAR-EQUATORIAL CONVECTION; MULTIPLE QUASI EQUILIBRIA; GENERAL-CIRCULATION; CUMULUS CONVECTION; MONSOON ONSET; PART-II; LOCATION; ORIGIN; WAVE AB It has been known for more than a decade that an aqua-planet model with a globally- and temporally-uniform sea surface temperature and solar isolation angle can generate intertropical convergence zones (ITCZ). Employing such a model, previous studies have shown that one of several means can be used to change between a single ITCZ over the equator and a double ITCZ straddling the equator. These means include switching to a different cumulus parametrization scheme, making changes within the cumulus parametrization scheme, and changing other aspects of the model such as horizontal resolution. Here, an interpretation of these findings is offered. In an aqua-planet model with globally and temporally uniform sea surface temperature and solar isolation angle, the latitudinal location of an ITCZ is the latitude where a balance exists between two types of attraction, both resulting from the Earth's rotation. The first attraction pulls the ITCZ towards the equator and is not sensitive to changes in model design. It is directly related to the Coriolis parameter, which provides stability to the atmosphere. The second ssattraction pulls the ITCZ poleward and is sensitive to changes in model design. It is related to the convective circulation, modified by the Coriolis force. A balance between the two types of attraction is reached either at the equator or more than 10degrees north and south of the equator, depending on the shape and magnitude of the attractions. A balance at the equator yields a single ITCZ over the equator, whereas a balance north and south of the equator yields a double ITCZ straddling the equator. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, GEST Ctr, Baltimore, MD 21228 USA. RP Chao, WC (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Mail Code 913, Greenbelt, MD 20771 USA. EM winston.c.chao@nasa.gov NR 25 TC 25 Z9 25 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0930-7575 J9 CLIM DYNAM JI Clim. Dyn. PD APR PY 2004 VL 22 IS 4 BP 447 EP 459 DI 10.1007/s00382-003-0387-4 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 808JG UT WOS:000220564800008 ER PT J AU Helvey, M AF Helvey, M TI Seeking consensus on designing marine protected areas: Keeping the fishing community engaged SO COASTAL MANAGEMENT LA English DT Article DE Channel Islands; community participation; MPAs; marine reserves ID FISHERIES MANAGEMENT; REEF FISHES; RESERVES; CONSERVATION; HABITAT; EXPERIENCE; BENEFITS; ISLANDS; ISSUES; OCEAN AB A community group was formed to consider establishing marine reserves within the Channel Islands National Marine Sanctuary in southern California. Membership included representatives from resource agencies, environmental organizations, commercial and recreational fishing interests, and the general public. While the group agreed on several areas for fishing closures, members could not reach consensus on a specific network design. Several factors interfered with the group's effort in attaining agreement resulting in the endeavor subsequently being replaced by a "topdown" approach that lacks the support of the fishing community. Lessons learned from the project emphasize the need by marine protected area participants to recognize irreconcilable impasses early in the process and to seek solutions to maneuver around them. The importance of keeping the fishing community fully engaged is discussed. C1 NOAA, Fisheries, Habitat Conservat Div, SW Reg,Natl Marine Fisheries Serv, Long Beach, CA 90802 USA. RP Helvey, M (reprint author), NOAA, Fisheries, Habitat Conservat Div, SW Reg,Natl Marine Fisheries Serv, 501 W Ocean Blvd,suite 4200, Long Beach, CA 90802 USA. EM mark.helvey@noaa.gov NR 58 TC 53 Z9 54 U1 2 U2 16 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0892-0753 J9 COAST MANAGE JI Coast. Manage. PD APR-JUN PY 2004 VL 32 IS 2 BP 173 EP 190 DI 10.1080/08920750490276236 PG 18 WC Environmental Sciences; Environmental Studies SC Environmental Sciences & Ecology GA 777UG UT WOS:000189196200006 ER PT J AU Harstad, K Bellan, J AF Harstad, K Bellan, J TI Modeling evaporation of Jet A, JP-7, and RP-1 drops at 1 to 15 bars SO COMBUSTION AND FLAME LA English DT Article DE evaporation of multicomponent drops ID CONTINUOUS THERMODYNAMICS; CONTINUOUS MIXTURES; VAPORIZATION; COMBUSTION; DROPLETS; GAS AB A model describing the evaporation of all isolated drop of a multicomponent fuel containing hundreds of species has been developed. The model is based oil continuous thermodynamics concepts wherein the composition of a fuel is statistically described using a probability distribution function (PDF). Following previous studies, this PDF is parametrized oil the species molar weight. However. unlike ill previous Studies, a unified formulation is developed wherein the same PDF holds for three Major homologous hydrocarbon classes. The new PDF is a double-Gamma-PDF that is parametrized on the square root of the molar weight. The additional advantage of the formulation is that it is valid in the subcritical region from I to 15 bars. Discrete species distributions for Jet A. JP-7. and RP-I are fitted using this novel PDF and extensive calculations for isolated drops of these kerosenes are performed. The results show that under the quasi-steady gas phase assumption, the D-2 law is recovered after all initial transient. The evaporation constant is an increasing function of the far field temperature and pressure and a complex function of far field composition according to the values of the far field temperature and pressure. The difference between the Surface and the far field vapor molar fraction is nearly independent of the far field pressure. The composition of the vapor at the drop surface is kerosene-fuel specific. A comparison between results obtained with a model assuming the drop interior to be well mixed and a model wherein the drop may evaporate either in a well-mixed mode or at unchanging composition shows that the percentage difference between the evaporation constant predicted by the two models is within the range Of Uncertainty in the transport properties. (C) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bellan, J (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,M-S 125-109, Pasadena, CA 91109 USA. EM josette.bellan@jpl.nasa.gov NR 31 TC 24 Z9 24 U1 0 U2 12 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD APR PY 2004 VL 137 IS 1-2 BP 163 EP 177 DI 10.1016/j.combustflame.2004.01.012 PG 15 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 813LK UT WOS:000220908400010 ER PT J AU Olson, SL Hegde, U Bhattacharjee, S Deering, JL Tang, L Altenkirch, RA AF Olson, SL Hegde, U Bhattacharjee, S Deering, JL Tang, L Altenkirch, RA TI Sounding rocket microgravity experiments elucidating diffusive and radiative transport effects on flame spread over thermally thick solids SO COMBUSTION SCIENCE AND TECHNOLOGY LA English DT Article DE microgravity; flame spread; thick solid; radiation; opposed flow AB A series of 6-min microgravity combustion experiments of opposed-flow flame spread over thermally thick PMMA has been conducted to extend data previously reported at high opposed flows to almost two decades lower in flow. The effect of flow velocity on flame spread shows a square-root power-law dependence rather than the linear dependence predicted by thermal theory. The experiments demonstrate that opposed-flow flame spread is viable to very low velocities and is more robust than expected from the two-dimensional numerical model, which predicts that, at very low velocities (<5 cm/s), flame spread rates fall off more rapidly as flow is reduced. It is hypothesized that the enhanced flame spread observed in the experiments may be due to three-dimensional hydrodynamic effects, which are not included in the zero-gravity, two-dimensional hydrodynamic model. The effect of external irradiation was also studied and its effects were found to be more complex than the model predicted over the 0-2 W/cm(2) range. In the experiments, the flame compensated for the increased irradiation by stabilizing farther from the surface. A surface energy balance reveals that the imposed flux was at least partially offset by a reduced conductive flux from the increased standoff distance so that the effect on flame spread was weaker than anticipated. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Natl Ctr Micrograv Res, Cleveland, OH USA. San Diego State Univ, San Diego, CA 92182 USA. Washington State Univ, Pullman, WA 99164 USA. New Jersey Inst Technol, Newark, NJ 07102 USA. RP Olson, SL (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM sandra.olson@grc.nasa.gov NR 20 TC 9 Z9 10 U1 0 U2 8 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0010-2202 J9 COMBUST SCI TECHNOL JI Combust. Sci. Technol. PD APR PY 2004 VL 176 IS 4 BP 557 EP 584 DI 10.1080/00102200490276773 PG 28 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Energy & Fuels; Engineering GA 778TU UT WOS:000189257500004 ER PT J AU Goyal, VK Jaunky, NR Johnson, ER Ambur, DR AF Goyal, VK Jaunky, NR Johnson, ER Ambur, DR TI Intralaminar and interlaminar progressive failure analyses of composite panels with circular cutouts SO COMPOSITE STRUCTURES LA English DT Article DE progressive failure analyses; delamination; ply failure ID LAMINATED COMPOSITES; DELAMINATION; INTERFACE; SIMULATION; IMPACT AB A progressive failure methodology is developed and demonstrated to simulate the initiation and material degradation of a laminated panel due to intralaminar and interlaminar failures. Initiation of intralaminar failure can be by a matrix-cracking mode, a fiber-matrix shear mode, and a fiber failure mode. Subsequent material degradation is modeled using damage parameters for each mode to selectively reduce lamina material properties. The interlaminar failure mechanism such as delamination is simulated by positioning interface elements between adjacent sublaminates. A nonlinear constitutive law is postulated for the interface element that accounts for a multi-axial stress criteria to detect the initiation of delamination, a mixed-mode fracture criteria for delamination progression, and a damage parameter to prevent restoration of a previous cohesive state. The methodology is validated using experimental data available in the literature on the response and failure of quasi-isotropic panels with centrally located circular cutouts loaded into the postbuckling regime. Very good agreement between the progressive failure analyses and the experimental results is achieved if the failure analyses includes the interaction of intralaminar and interlaminar failures. (C) 2003 Elsevier Ltd. All rights reserved. C1 Virginia Polytech Inst & State Univ, Dept Aerosp & Ocean Engn, Blacksburg, VA 24061 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Johnson, ER (reprint author), Virginia Polytech Inst & State Univ, Dept Aerosp & Ocean Engn, 215 Randolph Hall,MS 0203, Blacksburg, VA 24061 USA. EM vigoyal@vt.edu; navin@nianet.org; erjohns4@vt.edu; d.r.ambur@larc.nasa.gov NR 20 TC 40 Z9 41 U1 1 U2 10 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0263-8223 J9 COMPOS STRUCT JI Compos. Struct. PD APR PY 2004 VL 64 IS 1 BP 91 EP 105 DI 10.1016/S0263-8223(03)00217-4 PG 15 WC Materials Science, Composites SC Materials Science GA 844HI UT WOS:000223148500010 ER PT J AU Acker, JG Vasilkov, A Nadeau, D Kuring, N AF Acker, JG Vasilkov, A Nadeau, D Kuring, N TI Use of SeaWiFS ocean color data to estimate neritic sediment mass transport from carbonate platforms for two hurricane-forced events SO CORAL REEFS LA English DT Article DE hurricanes; neritic carbonates; remote sensing; sediment transport ID STATES VIRGIN-ISLANDS; CALCIUM-CARBONATE; FRENCH-POLYNESIA; MOOREA ISLAND; ST-CROIX; MODEL; BANK; PHYTOPLANKTON; ACCUMULATION; REFLECTANCE AB Plumes of neritic sediment caused by the passage of Hurricane Gert near Bermuda in 1999, and by the passage of Hurricane Michelle over Cuba's Gulf of Batabano in 2001, were observed by the Sea-viewing Wide Field-of-view Sensor (SeaWiFS). The mass of sediments in each of these plumes, which consist largely of neritic carbonate particles, was estimated using an algorithm for the calculation of suspended sediment concentrations. The Bermuda and Batabano plumes transported 0.22 and 1.2-1.35 million kg of sediment, respectively. The algorithm results were compared with the results from two other sediment mass algorithms and proved to be consistent. These results indicate the potential use of remote sensing to estimate carbonate flux from coral reefs and banks and atolls as an augmentation to in situ studies. In addition, the use of remote sensing data may improve estimates of the annual global carbonate sediment flux, a quantity important to models of global carbonate production and the global carbon cycle. C1 NASA, Goddard Space Flight Ctr, SeaWiFS Project, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Acker, JG (reprint author), NASA, Goddard Space Flight Ctr, SeaWiFS Project, Code 902, Greenbelt, MD 20771 USA. EM acker@daac.gsfc.nasa.gov NR 33 TC 14 Z9 15 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0722-4028 J9 CORAL REEFS JI Coral Reefs PD APR PY 2004 VL 23 IS 1 BP 39 EP 47 DI 10.1007/s00338-003-0355-9 PG 9 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 813WM UT WOS:000220937200005 ER PT J AU Brock, JC Wright, CW Clayton, TD Nayegandhi, A AF Brock, JC Wright, CW Clayton, TD Nayegandhi, A TI LIDAR optical rugosity of coral reefs in Biscayne National Park, Florida SO CORAL REEFS LA English DT Article DE aircraft remote sensing; LIDAR; rugosity; monitoring; Florida Keys ID HABITAT CHARACTERISTICS; FISH ASSEMBLAGES; VIRGIN-ISLANDS; COMMUNITIES; FORESTS; GROWTH; DEPTH; USA AB The NASA Experimental Advanced Airborne Research Lidar (EAARL), a temporal waveform-resolving, airborne, green wavelength LIDAR (light detection and ranging), is designed to measure the submeter-scale topography of shallow reef substrates. Topographic variability is a prime component of habitat complexity, an ecological factor that both expresses and controls the abundance and distribution of many reef organisms. Following the acquisition of EAARL coverage over both mid-platform patch reefs and shelf-margin bank reefs within Biscayne National Park in August 2002, EAARL-based optical indices of topographic variability were evaluated at 15 patch reef and bank reef sites. Several sites were selected to match reefs previously evaluated in situ along underwater video and belt transects. The analysis used large populations of submarine topographic transects derived from the examination of closely spaced laser spot reflections along LIDAR raster scans. At all 15 sites, each LIDAR transect was evaluated separately to determine optical rugosity (Ro(tran)), and the average elevation difference between adjacent points (Av(deltaE(ap))). Further, the whole-site mean and maximum values of Ro(tran) and Av(deltaE(ap)) for the entire population of transects at each analysis site, along with their standard deviations, were calculated. This study revealed that the greater habitat complexity of inshore patch reefs versus outer bank reefs results in relative differences in topographic complexity that can be discerned in the laser returns. Accordingly, LIDAR sensing of optical rugosity is proposed as a complementary new technique for the rapid assessment of shallow coral reefs. C1 USGS Ctr Coastal & Watershed Studies, St Petersburg, FL 33701 USA. NASA, Goddard Space Flight Ctr, Wallops Flight Facil, Wallops Isl, VA 23337 USA. RP Brock, JC (reprint author), USGS Ctr Coastal & Watershed Studies, 600 4th St S, St Petersburg, FL 33701 USA. EM jbrock@usgs.gov NR 40 TC 78 Z9 81 U1 2 U2 23 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0722-4028 J9 CORAL REEFS JI Coral Reefs PD APR PY 2004 VL 23 IS 1 BP 48 EP 59 DI 10.1007/s00338-003-0365-7 PG 12 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 813WM UT WOS:000220937200006 ER PT J AU Holstein, GR Martinelli, GP Boyle, R Rabbitt, RD Highstein, SM AF Holstein, GR Martinelli, GP Boyle, R Rabbitt, RD Highstein, SM TI Ultrastructural observations of efferent terminals in the crista Ampullaris of the toadfish, opsanus tau SO EXPERIMENTAL BRAIN RESEARCH LA English DT Article DE vestibular morphology; inner ear; semicircular canal; nervous system; balance ID GENE-RELATED PEPTIDE; SEMICIRCULAR CANAL AFFERENTS; TURTLE POSTERIOR-CRISTA; VESTIBULAR HAIR-CELLS; FROG LABYRINTH; HORSERADISH-PEROXIDASE; FINE-STRUCTURE; INNER-EAR; SYNAPTIC TRANSMISSION; NERVE-TERMINALS AB The present study was conducted to visualize the ultrastructural features of vestibular efferent boutons in the oyster toadfish, Opsanus tau. The crista ampullaris of the horizontal semicircular canal was processed for and examined by routine transmission electron microscopy. The results demonstrate that such boutons vary in size and shape, and contain a heterogeneous population of lucent vesicles with scattered dense core vesicles. Efferent contacts with hair cells are characterized by local vesicle accumulations in the presynaptic terminal and a subsynaptic cistern in the postsynaptic region of the hair cell. Serial efferent to hair cell to afferent synaptic arrangements are common, particularly in the central portion of the crista. However, direct contacts between efferent terminals and afferent neurites were not observed in our specimens. The existence of serial synaptic contacts, often with a row of vesicles in the efferent boutons lining the efferent-afferent membrane apposition, suggests that the efferent influence on the crista may involve both synaptic and nonsynaptic, secretory mechanisms. Further, it is suggested that differences in more subtle aspects of synaptic architecture and/or transmitter and receptor localization and interaction may render the efferent innervation of the peripheral crista less effective in influencing sensory processing. C1 Mt Sinai Sch Med, Dept Neurol, New York, NY 10029 USA. NASA, Ames BioVIS Technol Ctr, Moffett Field, CA 94035 USA. Univ Utah, Dept Bioengn, Salt Lake City, UT 84112 USA. Washington Univ, Dept Otolaryngol & Neurobiol, St Louis, MO USA. Marine Biol Lab, Woods Hole, MA 02543 USA. RP Holstein, GR (reprint author), Mt Sinai Sch Med, Dept Neurol, 1 Gustave L Levy Pl, New York, NY 10029 USA. EM gay.holstein@mssm.edu FU NIDCD NIH HHS [P01 DC-01837] NR 78 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0014-4819 J9 EXP BRAIN RES JI Exp. Brain Res. PD APR PY 2004 VL 155 IS 3 BP 265 EP 273 DI 10.1007/s00221-003-1734-8 PG 9 WC Neurosciences SC Neurosciences & Neurology GA 800KB UT WOS:000220026100001 PM 14689144 ER PT J AU Rashidnia, N Balasubramaniam, R AF Rashidnia, N Balasubramaniam, R TI Measurement of the mass diffusivity of miscible liquids as a function of concentration using a common path shearing interferometer SO EXPERIMENTS IN FLUIDS LA English DT Article ID COEFFICIENT AB A common path-shearing interferometer was adapted, using a Wollaston prism, to measure the diffusion coefficient for mass transfer of transparent, miscible liquids. The mathematics was developed for the time-dependent, one-dimensional diffusion process in a test cell when the diffusivity is a function of the local concentration of the fluids, and a procedure was devised to determine the diffusivity from the measured concentration gradient profiles. The results show that for diffusion in a water/glycerine system, the diffusivity depends on the concentration in an almost linear fashion. In the case of the silicone oils, the diffusivity was found to be nearly independent of the local concentration. C1 NASA, Glenn Res Ctr, Natl Ctr Micrograv Res Fluids & Combust, Cleveland, OH 44135 USA. RP Balasubramaniam, R (reprint author), NASA, Glenn Res Ctr, Natl Ctr Micrograv Res Fluids & Combust, Mail Stop 110-3, Cleveland, OH 44135 USA. EM bala@grc.nasa.gov NR 17 TC 17 Z9 18 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0723-4864 J9 EXP FLUIDS JI Exp. Fluids PD APR PY 2004 VL 36 IS 4 BP 619 EP 626 DI 10.1007/s00348-003-0735-5 PG 8 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 813WN UT WOS:000220937300011 ER PT J AU Bebout, BM Hoehler, TM Thamdrup, B Albert, D Carpenter, SP Hogan, M Turk, K Des Marais, DJ AF Bebout, Brad M. Hoehler, Tori M. Thamdrup, Bo Albert, Dan Carpenter, Steven P. Hogan, Mary Turk, Kendra Des Marais, David J. TI Methane production by microbial mats under low sulphate concentrations SO GEOBIOLOGY LA English DT Article AB Cyanobacterial mats collected in hypersaline salterns were incubated in a greenhouse under low sulphate concentrations ([SO(4)(2-)]) and examined for their primary productivity and emissions of methane and other major carbon species. Atmospheric greenhouse warming by gases such as carbon dioxide and methane must have been greater during the Archean than today in order to account for a record of moderate to warm palaeoclimates, despite a less luminous early sun. It has been suggested that decreased levels of oxygen and sulphate in Archean oceans could have significantly stimulated microbial methanogenesis relative to present marine rates, with a resultant increase in the relative importance of methane in maintaining the early greenhouse. We maintained modern microbial mats, models of ancient coastal marine communities, in artificial brine mixtures containing both modern [SO(4)(2-)] (c. 70 m M) and 'Archean' [SO(4)(2-)] (< 0.2 mM). At low [SO(4)(2-)], primary production in the mats was essentially unaffected, while rates of sulphate reduction decreased by a factor of three, and methane fluxes increased by up to 10-fold. However, remineralization by methanogenesis still amounted to less than 0.4% of the total carbon released by the mats. The relatively low efficiency of conversion of photosynthate to methane is suggested to reflect the particular geometry and chemical microenvironment of hypersaline cyanobacterial mats. Therefore, such mats were probably relatively weak net sources of methane throughout their 3.5 Ga history, even during periods of low environmental levels oxygen and sulphate. C1 [Bebout, Brad M.; Hoehler, Tori M.; Carpenter, Steven P.; Des Marais, David J.] NASA, Exobiol Branch, Ames Res Ctr, Moffett Field, CA 94035 USA. [Thamdrup, Bo] Univ So Denmark, Inst Biol, DK-5230 Odense M, Denmark. [Albert, Dan] Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA. [Hogan, Mary; Turk, Kendra] Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. RP Bebout, BM (reprint author), NASA, Exobiol Branch, Ames Res Ctr, Mail Stop 239-4, Moffett Field, CA 94035 USA. EM brad.m.bebout@nasa.gov RI Thamdrup, Bo/F-3889-2016 OI Thamdrup, Bo/0000-0002-1221-7077 FU NASA's Exobiology Program; NASA Astrobiology Institute FX This work was funded by grants from NASA's Exobiology Program, and the NASA Astrobiology Institute. We are very grateful for continued access to the field site and logistical support provided by Exportadora de Sal, S. A. de C. V. The thoughtful comments of C. A. Kelley and two anonymous reviewers greatly improved the manuscript. NR 54 TC 32 Z9 33 U1 0 U2 9 PU WILEY-BLACKWELL PUBLISHING, INC PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1472-4677 J9 GEOBIOLOGY JI Geobiology PD APR PY 2004 VL 2 IS 2 BP 87 EP 96 DI 10.1111/j.1472-4677.2004.00024.x PG 10 WC Biology; Environmental Sciences; Geosciences, Multidisciplinary SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Geology GA V06CJ UT WOS:000207171400002 ER PT J AU McCanta, MC Rutherford, MJ Jones, JH AF McCanta, MC Rutherford, MJ Jones, JH TI An experimental study of rare earth element partitioning between a shergottite melt and pigeonite: implications for the oxygen fugacity of the martian interior SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID OVERLYING SUBDUCTION ZONES; OXIDATION-STATE; SILICATE LIQUIDS; TRACE-ELEMENT; REDOX STATES; UPPER-MANTLE; LOS-ANGELES; METEORITE; MARS; PETROGENESIS AB A series of experiments on a synthetic, pigeonite-saturated, basaltic shergottite were carried out to constrain the variation of D(Eu/Gd)(pigeonite/melt) and D(Eu/Sm)(pigeonite/melt) with oxygen fugacity (f(O2)). The experiments have been run Under both dry and hydrous conditions. The shergottite was doped with 0.1, 0.5, and 1.0 wt.% Eu. Gd, and Sin oxides in different experiments and was equilibrated at liquidus conditions for 24 hours. D(Eu/Gd)(pigeonite/melt) in dry melts ranges from 0. 156 +/- 0.014 (f(O2) = IW - 1) to 0.630 +/- 0.102 (IW + 3.5). D(Eu/Sm)(pigeonite/melts) in dry melts ranges from 0.279 +/- 0.021 (IW - 1) to 1.114 +/- 0.072 (IW + 3.5). Due to difficulties with low-f(O2) experiments, hydrous distribution coefficients were measured, but were not used in the calibration of the Eu-oxybarometers. These two Eu-oxybarometers provide ail accurate way to measure f(O2) recorded during pigeonite crystallization, thereby yielding a record of f(O2) during the earliest period of Martian meteorite parent magma crystallization history. Using this new calibration, Martian meteorite pigeonite cores record f(O2) values of IW - 0.6 (+/-0.3) (QUE94201) to IW + 1.9 (+/-0.6) (Shergotty). These new values differ in magnitude, but not trend, from previously published data. The pigeonite Eu-oxybarometer yields f(O2) range in the basaltic shergottites of 2 to 3 orders of magnitude. Several processes have been proposed to explain the origin of fO2 range, the majority of which rely on assimilation of an oxidized source. A potential correlation between this new pigeonite data and recent Fe-Ti oxide data, however, is consistent with intrinsic f(O2) differences in the magma source region being responsible for the measured variations. This implies that the Martian meteorite source region. the mantle or lithosphere, may he heterogeneous in nature. However, the process of assimilation cannot be completely ruled Out ill that an assimilation event that took place before crystallization commenced would result in the overprinting of the Source re ion signature. Copyright (C) 2004 Elsevier Ltd. C1 Brown Univ, Dept Geol Sci, Providence, RI 02912 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP McCanta, MC (reprint author), Brown Univ, Dept Geol Sci, 324 Brook St, Providence, RI 02912 USA. EM molly_mccanta@brown.edu RI Facility, NENIMF/B-8811-2015 NR 51 TC 35 Z9 36 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD APR PY 2004 VL 68 IS 8 BP 1943 EP 1952 DI 10.1016/j.gca.2003.10.019 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 813FD UT WOS:000220892100018 ER PT J AU Gross, RS Blewitt, G Clarke, PJ Lavallee, D AF Gross, RS Blewitt, G Clarke, PJ Lavallee, D TI Degree-2 harmonics of the Earth's mass load estimated from GPS and Earth rotation data SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID OCEAN TIDES; DEFORMATION; EXCITATION; INVERSION; MOTION; WOBBLE AB A fluid, mobile atmosphere and oceans surrounds the solid Earth and upon its land surface lays a continually changing distribution of ice, snow, and ground water. The changing distribution of mass associated with the motion of these surficial fluids changes the Earth's rotation by changing its inertia tensor and changes the Earth's shape by changing the load on the solid Earth. It has recently been demonstrated that large-scale changes of the Earth's shape, and hence of the mass load causing the Earth's shape to change, can be measured using the global network of GPS receivers. Here, the degree-2 mass load coefficients determined from GPS data are compared with those obtained from Earth orientation observations from which the effects of tides, winds, and currents have been removed. Good agreement is found between these two estimates of the degree-2 mass load, particularly at seasonal frequencies. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Nevada, Reno, NV 89557 USA. Univ Newcastle Upon Tyne, Sch Civil Engn & Geosci, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England. RP Gross, RS (reprint author), CALTECH, Jet Prop Lab, MS 238-332,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM richard.gross@jpl.nasa.gov; gblewitt@unr.edu; peter.clarke@newcastle.ac.uk RI Clarke, Peter/B-1783-2008 OI Clarke, Peter/0000-0003-1276-8300 NR 16 TC 25 Z9 26 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 1 PY 2004 VL 31 IS 7 AR L07601 DI 10.1029/2004GL019589 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 811AB UT WOS:000220743700005 ER PT J AU Parry, ML Rosenzweig, C Iglesias, A Livermore, M Fischer, G AF Parry, ML Rosenzweig, C Iglesias, A Livermore, M Fischer, G TI Effects of climate change on global food production under SRES emissions and socio-economic scenarios SO GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS LA English DT Article DE climate change; SRES emissions scenarios; global food security; cereal yields; risk of hunger ID CO2; RESPONSES; CROPS AB This paper analyses the global consequences to crop yields, production, and risk of hunger of linked socio-economic and climate scenarios. Potential impacts of climate change are estimated for climate change scenarios developed from the HadCM3 global climate model under the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (SRES) A1FI, A2, B I, and B2. Projected changes in yield are calculated using transfer functions derived from crop model simulations with observed climate data and projected climate change scenarios. The basic linked system (BLS) is used to evaluate consequent changes in global cereal production, cereal prices and the number of people at risk from hunger. The crop yield results elucidate the complex regional patterns of projected climate variables, CO2 effects, and agricultural systems that contribute to aggregations of global crop production. The A1FI scenario, as expected with its large increase in global temperatures, exhibits the greatest decreases both regionally and globally in yields, especially by the 2080s. The contrast between the yield change in developed and developing countries is largest under the A2a-c scenarios. Under the 131 and B2 scenarios, developed and developing countries exhibit less contrast in crop yield changes, with the B2 future crop yield changes being slightly more favourable than those of the B1 scenario. When crop yield results are introduced to the BLS world food trade system model, the combined model and scenario experiments demonstrate that the world, for the most part, appears to be able to continue to feed itself under the SRES scenarios during the rest of this century. However, this outcome is achieved through production in the developed countries (which mostly benefit from climate change) compensating for declines projected, for the most part, for developing nations. While global production appears stable, regional differences in crop production are likely to grow stronger through time, leading to a significant polarisation of effects, with substantial increases in prices and risk of hunger amongst the poorer nations, especially under scenarios of greater inequality (A1FI and A2). The use of the SRES scenarios highlights several non-linearities in the world food supply system, both in the biophysical sense, where the levels of atmospheric CO2 tested reach new levels, and the socio-economic sense, where changes in population dynamics and economic and political structures complicate the translation of biophysical climate change impacts into social indices, such as the number of people at risk of hunger. (C) 2003 Elsevier Ltd. All rights reserved. C1 UK Meteorol Off, Hadley Ctr, Exeter EX1 3PB, Devon, England. Int Inst Appl Syst Anal, A-2361 Laxenburg, Austria. Univ E Anglia, Climat Res Unit, Norwich NR4 7TJ, Norfolk, England. Univ Politecn Madrid, Madrid, Spain. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Parry, ML (reprint author), UK Meteorol Off, Hadley Ctr, Fitzroy Rd, Exeter EX1 3PB, Devon, England. EM parryml@aol.com NR 16 TC 603 Z9 642 U1 55 U2 292 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0959-3780 J9 GLOBAL ENVIRON CHANG JI Glob. Environ. Change-Human Policy Dimens. PD APR PY 2004 VL 14 IS 1 BP 53 EP 67 DI 10.1016/j.gloenvcha.2003.10.008 PG 15 WC Environmental Sciences; Environmental Studies; Geography SC Environmental Sciences & Ecology; Geography GA 776TX UT WOS:000189135000005 ER PT J AU Johnson, LF Pierce, LL AF Johnson, LF Pierce, LL TI Indirect measurement of leaf area index in California North Coast vineyards SO HORTSCIENCE LA English DT Article DE LAI; winegrape; LI-COR Plant Canopy Analyzer; light interception; remote sensing ID GRAPEVINES; DENSITY AB The performance of the LI-COR LAI-2000 Plant Canopy Analyzer (PCA) for indirect measurement of leaf area index (LAI) was evaluated in vineyards of California's North Coast region. Twelve plots were established, representing vineyards of differing trellis, cultivar, and planting density. Mean LAI ranged from 0.5- to 2.25-m(2) leaf area per m(2) ground area by direct measurement (defoliation). Indirect LAI derived by a standard two-azimuth, diagonal-transect measurement protocol was significantly related to direct LAI (r(2) = 0.78, P less than or equal to 0.001). However, the PCA underestimated direct LAI by about a factor of two. Narrowing the instrument's conical field of view from 148degrees to 56degrees increased indirect LAI by 13% to 60% in vertically trained plots, but still resulted in substantial underestimation of direct values. Use of this PCA protocol in vineyards should therefore be accompanied by direct measurement for calibration purposes. C1 Calif State Univ, Inst Earth Syst Sci & Policy, NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Calif State Univ, Inst Earth Syst Sci & Policy, Seaside, CA 93955 USA. RP Johnson, LF (reprint author), Calif State Univ, Inst Earth Syst Sci & Policy, NASA, Ames Res Ctr, MS242-4, Moffett Field, CA 94035 USA. EM ljohnson@mail.arc.nasa.gov NR 16 TC 18 Z9 19 U1 0 U2 7 PU AMER SOC HORTICULTURAL SCIENCE PI ALEXANDRIA PA 113 S WEST ST, STE 200, ALEXANDRIA, VA 22314-2851 USA SN 0018-5345 J9 HORTSCIENCE JI Hortscience PD APR PY 2004 VL 39 IS 2 BP 236 EP 238 PG 3 WC Horticulture SC Agriculture GA 814KO UT WOS:000220973800005 ER PT J AU Heldmann, JL Mellon, MT AF Heldmann, JL Mellon, MT TI Observations of martian gullies and constraints on potential formation mechanisms SO ICARUS LA English DT Article DE Mars; geological processes ID THERMAL HISTORY; LIQUID WATER; TERRESTRIAL PLANETS; GROUND ICE; MARS; EVOLUTION; CHRONOLOGY; FEATURES; DEPOSITS; SEEPAGE AB The discovery of presumably geologically recent gully features on Mars (Malin and Edgett, 2000, Science 288, 2330-2335) has spawned a wide variety of proposed theories of their origin including hypotheses of the type of erosive material. To test the validity of gully formation mechanisms, data from the Mars Global Surveyor spacecraft has been analyzed to uncover trends in the dimensional and physical properties of the gullies and their surrounding terrain. We located 106 Mars Orbiter Camera (MOC) images that contain clear evidence of gully landforms, distributed in the southern mid and high latitudes, and analyzed these images in combination with Mars Orbiter Laser Altimeter (MOLA) and Thermal Emission Spectrometer (TES) data to provide quantitative measurements of numerous gully characteristics. Parameters we measured include apparent source depth and distribution, vertical and horizontal dimensions, slopes, orientations, and present-day characteristics that affect local ground temperatures. We find that the number of gully systems normalized to the number of MOC images steadily declines as one moves poleward of 30degrees S, reaches a minimum value between 60degrees-63degrees S, and then again rises poleward of 63degrees S. All gully alcove heads occur within the upper one-third of the slope encompassing the gully and the alcove bases occur within the upper two-thirds of the slope. Also, the gully alcove heads occur typically within the first 200 meters of the overlying ridge with the exception of gullies equatorward of 40degrees S where some alcove heads reach a maximum depth of 1000 meters. While gullies exhibit complex slope orientation trends, gullies are found on all slope orientations at all the latitudes studied. Assuming thermal conductivities derived from TES measurements as well as modeled surface temperatures, we find that 79% of the gully alcove bases lie at depths where subsurface temperatures are greater than 273 K and 21% of the alcove bases lie within the solid water regime. Most of the gully alcoves lie outside the temperature-pressure phase stability of liquid CO2. Based on a comparison of measured gully features with predictions from the various models of gully formation, we find that models involving carbon dioxide, melting ground ice in the upper few meters of the soil, dry landslide, and surface snowmelt are the least likely to describe the formation of the martian gullies. Although some discrepancies still exist between prediction and observation, the shallow and deep aquifer models remain as the most plausible theories. Interior processes involving subsurface fluid sources are generally favored over exogenic processes such as wind and snowfall for explaining the origin of the martian gullies. (C) 2003 Elsevier Inc. All rights reserved. C1 Univ Colorado, Boulder Lab Atmospher & Space Phys, Boulder, CO 80309 USA. RP Heldmann, JL (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM jheldmann@mail.arc.nasa.gov RI Mellon, Michael/C-3456-2016 NR 44 TC 104 Z9 106 U1 2 U2 8 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD APR PY 2004 VL 168 IS 2 BP 285 EP 304 DI 10.1016/j.icarus.2003.11.024 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807AL UT WOS:000220474300006 ER PT J AU Imanaka, H Khare, BN Elsila, JE Bakes, ELO McKay, CP Cruikshank, DP Sugita, S Matsui, T Zare, RN AF Imanaka, H Khare, BN Elsila, JE Bakes, ELO McKay, CP Cruikshank, DP Sugita, S Matsui, T Zare, RN TI Laboratory experiments of Titan tholin formed in cold plasma at various pressures: implications for nitrogen-containing polycyclic aromatic compounds in Titan haze SO ICARUS LA English DT Article DE Titan; haze; tholin; spectroscopy; organic chemistry; nitrogen-containing polycyclic aromatic compounds ID VOYAGER INFRARED OBSERVATIONS; ENERGETIC CHARGED-PARTICLES; AMORPHOUS-CARBON; SATURNS MAGNETOSPHERE; OPTICAL-PROPERTIES; UPPER-ATMOSPHERE; VERTICAL-DISTRIBUTION; ORGANIC-CHEMISTRY; HETERODYNE OBSERVATIONS; REDUCING ATMOSPHERES AB Titan, the largest satellite of Saturn, has a thick nitrogen/methane atmosphere with a thick global organic haze. A laboratory analogue of Titan's haze, called tholin, was formed in an inductively coupled plasma from nitrogen/methane = 90/10 gas mixture at various pressures ranging from 13 to 2300 Pa. Chemical and optical properties of the resulting tholin depend on the deposition pressure in cold plasma. Structural analyses by IR and UV/VIS spectroscopy, microprobe laser desorption/ionization mass spectrometry, and Raman spectroscopy suggest that larger amounts of aromatic ring structures with larger cluster size are formed at lower pressures (13 and 26 Pa) than at higher pressures (160 and 2300 Pa). Nitrogen is more likely to incorporate into carbon networks in tholins formed at lower pressures, while nitrogen is bonded as terminal groups at higher pressures. Elemental analysis reveals that the carbon/nitrogen ratio in tholins increases from 1.5-2 at lower pressures to 3 at 2300 Pa. The increase in the aromatic compounds and the decrease in C/N ratio in tholin formed at low pressures indicate the presence of the nitrogen-containing polycyclic aromatic compounds in tholin formed at low pressures. Tholin formed at high pressure (2300 Pa) consists of a polymer-like branched chain structure terminated with -CH(3), -NH(2), and -Cequivalent toN with few aromatic compounds. Reddish-brown tholin films formed at low pressures (13-26 Pa) shows stronger absorptions (almost 10 times larger k-value) in the UV/VIS range than the yellowish. tholin films formed at high pressures (160 and 2300 Pa). The tholins formed at low pressures may be better representations of Titan's haze than those formed at high pressures, because the optical properties of tholin formed at low pressures agree well with that of Khare et al. (1984a, Icarus 60, 127-137), which have been shown to account for Titan's observed geometric albedo. Thus, the nitrogen-containing polycyclic aromatic compounds we find in tholin formed at low pressure may be present in Titan's haze. These aromatic compounds may have a significant influence on the thermal structure and complex organic chemistry in Titan's atmosphere, because they are efficient absorbers of UV radiation and efficient charge exchange intermediaries. Our results also indicate that the haze layers at various altitudes might have different chemical and optical properties. (C) 2004 Elsevier Inc. All rights reserved. C1 NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. Univ Tokyo, Dept Earth & Planetary Sci, Tokyo, Japan. Stanford Univ, Dept Chem, Stanford, CA 94305 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Tokyo, Dept Complex Sci & Engn, Tokyo, Japan. RP Imanaka, H (reprint author), NASA, Ames Res Ctr, SETI Inst, MS239-11, Moffett Field, CA 94035 USA. EM himanaka@mail.arc.nasa.gov RI Zare, Richard/A-8410-2009; Elsila, Jamie/C-9952-2012; Imanaka, Hiroshi/E-7816-2012 NR 95 TC 183 Z9 185 U1 2 U2 26 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD APR PY 2004 VL 168 IS 2 BP 344 EP 366 DI 10.1016/j.icarus.2003.12.014 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807AL UT WOS:000220474300011 ER PT J AU Kress, ME McKay, CP AF Kress, ME McKay, CP TI Formation of methane in comet impacts: implications for Earth, Mars, and Titan SO ICARUS LA English DT Article DE atmospheres, evolution; impact processes; prebiotic environments; planetary formation; terrestrial planets; Titan ID SOLAR NEBULA; SURFACE TEMPERATURES; ATMOSPHERE; CHEMISTRY; CARBON; ORIGIN; CATALYSIS; EVOLUTION; MOLECULES; ORGANICS AB We calculate the amount of methane that may form via reactions catalyzed by metal-rich dust that condenses in the wake of large cometary impacts. Previous models of the gas-phase chemistry of impacts predicted that the terrestrial planets' atmospheres should be initially dominated by CO/CO2, N-2, and H2O. CH4 was not predicted to form in impacts because gas-phase reactions in the explosion quench at temperatures similar to 2000 K, at which point all of the carbon is locked in CO. We argue that the dust that condenses out in the wake of a large comet impact is likely to have very effective catalytic properties, opening up reaction pathways to convert CO and H-2 to CH4 and CO2, at temperatures of a few hundred K. Together with CO2, CH4 is an important greenhouse gas that has been invoked to compensate for the lower luminosity of the Sun similar to 4 Gyr ago. Here, we show that heterogeneous (gas-solid) reactions on freshly-recondensed dust in the impact cloud may provide a, plausible nonbiological mechanism for reducing CO to CH4 before and during the emergence of life on Earth, and perhaps Mars as well. These encouraging results emphasize the importance of future research into the kinetics and catalytic properties of astrophysical condensates or "smokes" and also more detailed models to determine the conditions in impact-generated dust clouds. (C) 2003 Published by Elsevier Inc. C1 Univ Washington, Dept Astron, Ctr Astrobiol & Early Evolut, Seattle, WA 98195 USA. NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Kress, ME (reprint author), Univ Washington, Dept Astron, Ctr Astrobiol & Early Evolut, Seattle, WA 98195 USA. EM kress@astro.washington.edu NR 37 TC 65 Z9 66 U1 1 U2 10 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD APR PY 2004 VL 168 IS 2 BP 475 EP 483 DI 10.1016/j.icarus.2003.10.013 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807AL UT WOS:000220474300021 ER PT J AU Cuzzi, JN AF Cuzzi, JN TI Blowing in the wind: III. Accretion of dust rims by chondrule-sized particles in a turbulent protoplanetary nebula SO ICARUS LA English DT Article DE meteorites; accretion; planetisimals; solar nebula; origin; Solar System; cosmochemistry ID UNEQUILIBRATED ORDINARY CHONDRITES; SOLAR NEBULA; PREPLANETARY DUST; CM CHONDRITES; MATRIX; COAGULATION; INCLUSIONS; MANTLES; GRAINS; MODELS AB The fabric of primitive meteorites is dominated by small but macroscopic particles-chondrules, refractory mineral inclusions (CAIs), metal grains, and their like. One interesting aspect of these particles is that they are often surrounded by well-attached rims of fine-grained dust which appear to have been "accreted" onto solid mineral cores. The rim thickness varies from one meteorite to another, but there seems to be a proportionality between the thickness of the rim and the size of the core. We make use of recently derived analytical expressions for absolute and relative velocities of chondrule-and-CAI-sized particles in a weakly turbulent nebula (Cuzzi and Hogan, 2003, paper I of this series) to assess the acquisition of fine-grained accretionary dust rims by particles in the chondrule-to-CAI size range. We compare these predictions with meteoritic observations, and show how the existence of fairly compact dust rims on chondrules and similar size objects can be easily understood within the turbulent nebula context. We estimate the time needed to accrete such rims to be in the 10(2)-10(3) year range. More observations of the form of the correlation between rim and core diameter in dust-rimmed chondrules are needed in order to strongly constrain the environment and history of these objects. Published by Elsevier Inc. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Cuzzi, JN (reprint author), NASA, Ames Res Ctr, Div Space Sci, MS 245-3, Moffett Field, CA 94035 USA. EM cuzzi@cosmic.arc.nasa.gov NR 47 TC 24 Z9 24 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD APR PY 2004 VL 168 IS 2 BP 484 EP 497 DI 10.1016/j.icarus.2003.12.008 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807AL UT WOS:000220474300022 ER PT J AU Khayatian, B Rahmat-Samii, Y AF Khayatian, B Rahmat-Samii, Y TI A novel antenna concept for future solar sails: Application of Fresnel antennas SO IEEE ANTENNAS AND PROPAGATION MAGAZINE LA English DT Article DE reflector antennas; lens antennas; physical optics; moment methods; space vehicle propulsion; extraterrestrial exploration; space vehicle antennas; multifrequency antennas; Fresnel zone plate; solar sail ID REFLECTOR ANTENNAS AB Recent studies have shown that interplanetary missions may be made possible using inflatable solar sails that employ solarflux power, providing thrust for spacecraft while reducing onboard fuel requirements. These sails require a large surface area (i.e., 100 m in diameter) to capture enough solar flux for spacecraft navigation. In this paper, a novel communication antenna concept is proposed for future solar-sail missions, taking advantage of the large sail surface area via application of Fresnelzone (FZ) antennas. This study focuses on utilizing a design/analysis methodology using Physical Optics (PO) and Method of Moments (MoM) for Fresnel-type antennas applicable to the solar-sail missions. Extensive parametric studies of Fresnel-zone antenna radiation characteristics have been performed, and the analytical methodologies were verified using a series of measurements. Fresnel-zone antenna gain is studied under different antenna configurations. Furthermore, a Fresnel-zone antenna under surface deformation is investigated to characterize Fresnel-zone antenna performance in the reflective mode. In addition, a new bandwidth-enhancement technique is introduced for Fresnel-zone antennas, to accommodate the dual-band operation ( X band uplink and downlink) of the antenna for the Deep Space Network (DSN). C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rahmat@ee.ucia.edu NR 14 TC 1 Z9 2 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1045-9243 EI 1558-4143 J9 IEEE ANTENN PROPAG M JI IEEE Antennas Propag. Mag. PD APR PY 2004 VL 46 IS 2 BP 50 EP 63 DI 10.1109/MAP.2004.1305534 PG 14 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 829LP UT WOS:000222050200007 ER PT J AU Amitai, E Nystuen, JA Liao, L Meneghini, R Morin, E AF Amitai, E. Nystuen, J. A. Liao, L. Meneghini, R. Morin, E. TI Uniting Space, Ground, and Underwater Measurements for Improved Estimates of Rain Rate SO IEEE GEOSCIENCE AND REMOTE SENSING LETTERS LA English DT Article DE Meteorological radar; rain gauge; rain intensity; rainfall; spaceborne radar; probability distribution function; Tropical Rainfall Measuring Mission (TRMM); underwater acoustic; validation AB Global precipitation is monitored from a variety of platforms including spaceborne, ground-, and ocean-based platforms. Intercomparisons of these observations are crucial to validating the measurements and providing confidence for each measurement technique. Probability distribution functions of rain rates are used to compare satellite and ground-based radar observations. A preferred adjustment technique for improving rain rate distribution estimates is identified using measurements from ground-based radar and rain gauges within the coverage area of the radar. The underwater measurement of rainfall shows similarities to radar measurements, but with intermediate spatial resolution and high temporal resolution. Reconciling these different measurement techniques provides understanding and confidence for all of the methods. C1 [Amitai, E.; Liao, L.; Meneghini, R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Amitai, E.] George Mason Univ, Fairfax, VA 22030 USA. [Nystuen, J. A.] Univ Washington, Appl Phys Lab, Seattle, WA 98195 USA. [Liao, L.] Caelum Res Corp, Rockville, MD 20850 USA. [Morin, E.] Hebrew Univ Jerusalem, IL-91905 Jerusalem, Israel. RP Amitai, E (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. FU National Aeronautics and Space Administration through TRMM Satellite Validation Office, Goddard Space Flight Center FX Manuscript received September 11, 2003; revised January 5, 2004. This work was supported by the National Aeronautics and Space Administration through the TRMM Satellite Validation Office, Goddard Space Flight Center. NR 5 TC 11 Z9 11 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1545-598X J9 IEEE GEOSCI REMOTE S JI IEEE Geosci. Remote Sens. Lett. PD APR PY 2004 VL 1 IS 2 BP 35 EP 38 DI 10.1109/LGRS.2004.824767 PG 4 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA V23ED UT WOS:000208325200001 ER PT J AU Yang, RQ Hill, CJ Yang, BH Wong, CM AF Yang, RQ Hill, CJ Yang, BH Wong, CM TI Type-II interband cascade lasers in the 4.3-4.7-mu m wavelength region SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE diode lasers; mid-infrared (IR); quantum-well (QW) lasers; semiconductor superlattices ID CONTINUOUS-WAVE OPERATION; ROOM-TEMPERATURE; MU-M; HEAT-SINKING; POWER AB Operation of type-II interband cascade lasers in the 4.3-4.7-mum wavelength region has been demonstrated at temperatures up to 240 K in pulsed mode. These lasers fabricated with 150-mum-wide mesa stripes operated in continuous-wave (CW) mode up to a maximum temperature of 110 K, with an output power exceeding 30 mW/f and a threshold current density of about 41 A/cm(2) at 90 K The maximum CW operation temperature of 110 K is largely limited by the high specific thermal resistance of the 150-mum-wide broad area lasers. A 20-mum-wide mesa stripe laser was able to operate in CW mode at higher temperatures up to 125 K as a result of the reduced specific thermal resistance of a smaller device. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yang, RQ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Rui.Q.Yang@jpl.nasa.gov NR 17 TC 7 Z9 8 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD APR PY 2004 VL 16 IS 4 BP 987 EP 989 DI 10.1109/LPT.2004.824947 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 809BR UT WOS:000220612700010 ER PT J AU Stevens, J Componation, PJ AF Stevens, J Componation, PJ TI Shuttle performance improvements through multiple database integration SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article AB The ability to model and analyze system performance is a key enabler when you are extending the operational life of complex systems. This is especially true when the system is operating in a hostile environment, such as space. This paper discusses a change made to the Space Shuttle main engines (SSMES) that affected the solid rocket booster (SRB) performance, and illustrates how databases maintained by the different subsystem contractors can be integrated, correlated, and evaluated to improve a subsystem component performance model. The enhanced model can be used not only for better prediction of component performance on the existing system, but can be used on upgrades to the system, or the next generation space shuttle solid rocket motor. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Univ Alabama, Coll Engn, Dept Ind & Management Syst Engn, Huntsville, AL 35801 USA. RP Stevens, J (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. EM pjc@ise.uah.edu NR 15 TC 1 Z9 1 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 2004 VL 40 IS 2 BP 478 EP 490 DI 10.1109/TAES.2004.1309999 PG 13 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 839NO UT WOS:000222792000007 ER PT J AU Wang, L Dawson, JM Hornak, LA Famouri, P Ghaffarian, R AF Wang, L Dawson, JM Hornak, LA Famouri, P Ghaffarian, R TI Real-time translational control of a MEMS comb resonator SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article AB Closed-loop control has been successfully applied to a microelectromechanical systems (MEMS) lateral comb resonator device in real-time to perform impulse disturbance damping and sinusoidal position control, enabled by the use of a through-wafer optical microprobe to obtain position feedback. This result leverages the application of lifetime, in-situ control of MEMS in order to provide quality assurance of microsystems in safety critical applications. A position feedback signal produced by a through-wafer optical microprobe has been used for comb resonator system model identification by two independent methods to accurately determine the effective mass, damping, and spring constant values of the device. After accurate determination of system parameters, closed-loop impulse disturbance damping and proportional-integral-differential (PID) translational control were applied. Closed-loop control results presented indicate controllability of such microstructures and response times on the order of the natural frequency of the device. C1 W Virginia Univ, Lane Dept Comp Sci & Elect Engn, Electromech Syst Res Lab, Microelect Syst Res Ctr, Morgantown, WV 26506 USA. Inst Sci Res, Fairmont, WV 26555 USA. NASA, Jet Prop Lab, Engn Assurance & Adv Technol Grp, Pasadena, CA 91109 USA. RP W Virginia Univ, Lane Dept Comp Sci & Elect Engn, Electromech Syst Res Lab, Microelect Syst Res Ctr, Morgantown, WV 26506 USA. EM jdawson@isr.us NR 12 TC 10 Z9 12 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9251 EI 1557-9603 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 2004 VL 40 IS 2 BP 567 EP 575 DI 10.1109/TAES.2004.1310005 PG 9 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 839NO UT WOS:000222792000013 ER PT J AU Karnik, T Hazucha, P Patel, J AF Karnik, T Hazucha, P Patel, J TI Characterization of soft errors caused by single event upsets in CMOS processes SO IEEE TRANSACTIONS ON DEPENDABLE AND SECURE COMPUTING LA English DT Article DE high performance; error tolerance; reliability; soft error; single event upset ID CHARGE COLLECTION MEASUREMENTS; TERRESTRIAL COSMIC-RAYS; MULTIPLE-BIT UPSET; SEU MEASUREMENTS; GROUND-LEVEL; ION TRACKS; NEUTRONS; SILICON; SIMULATION; PROTONS AB Fladiation-induced single event upsets (SEUs) pose a major challenge for the design of memories and logic circuits in high-performance microprocessors in technologies beyond 90nm. Historically, we have considered power-performance-area trade offs. There is a need to include the soft error rate (SER) as another design parameter. In this paper, we present radiation particle interactions with silicon, charge collection effects, soft errors, and their effect on VLSI circuits. We also discuss the impact of SEUs on system reliability. We describe an accelerated measurement of SERs using a high-intensity neutron beam, the characterization of SERs in sequential logic cells, and technology scaling trends. Finally, some directions for future research are given. C1 Intel Labs, Circuit Res, Hillsboro, OR 97124 USA. NASA, JPL, Pasadena, CA 91109 USA. RP Intel Labs, Circuit Res, 2111 NE 25th Ave, Hillsboro, OR 97124 USA. EM tanay.karnik@intel.com; peter.hazucha@intel.com; jupatel@jpl.nasa.gov RI Wang, Yuan/C-8792-2012 NR 95 TC 209 Z9 219 U1 1 U2 14 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1545-5971 EI 1941-0018 J9 IEEE T DEPEND SECURE JI IEEE Trans. Dependable Secur. Comput. PD APR-JUN PY 2004 VL 1 IS 2 BP 128 EP 143 DI 10.1109/TDSC.2004.14 PG 16 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA 009AF UT WOS:000235082800003 ER PT J AU Huang, HL Yang, P Wei, HL Baum, BA Hu, YX Antonelli, P Ackerman, SA AF Huang, HL Yang, P Wei, HL Baum, BA Hu, YX Antonelli, P Ackerman, SA TI Inference of ice cloud properties from high spectral resolution infrared observations SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE ice clouds; infrared spectrum; retrieval ID OCTOBER 1986 FIRE; CIRRUS CLOUDS; RADIATIVE PROPERTIES; LIGHT-SCATTERING; MU-M; MICROPHYSICAL PROPERTIES; OPTICAL-THICKNESS; WATER-VAPOR; ABSORPTION; RETRIEVAL AB The theoretical basis is explored for inferring the microphysical properties of ice clouds from high spectral resolution infrared (IR) observations. Extensive radiative transfer simulations are carried out to address relevant issues. The single-scattering properties of individual ice crystals are computed from state-of-the-art light scattering computational methods and are subsequently averaged for 30 in situ particle size distributions and for four additional analytical Gamma size distributions. The nonsphericity of ice crystals is shown to have a significant impact on the radiative signatures in the IR spectrum. Furthermore, the errors associated with the use of the Henyey-Greenstein phase function can be larger than I K in terms of brightness temperature for large particle effective sizes (similar to 80 mum) at wavenumbers where the scattering of the IR radiation by ice crystals is not negligible. The simulations undertaken in this paper show that the slope of the IR brightness temperature spectrum between 790-960 cm(-1) is sensitive to the effective particle size. Furthermore, a strong sensitivity of the IR brightness temperature to cloud optical thickness is noted within the 1050-1250-cm(-1) region. Based on these spectral features, a technique is presented for the simultaneous retrieval of the visible optical thickness and effective particle size from high spectral resolution IR data for ice clouds. An error analysis shows that the uncertainties of the retrieved optical thickness and effective particle size have a small range of variation. The error for retrieving particle size in conjunction with an uncertainty of 5 K in cloud temperature, or a surface temperature uncertainty of 2.5 K, is less than 15%. The corresponding errors in the uncertainty of optical thickness are within 5% to 20%, depending on the value of cloud optical thickness. The applicability of the present retrieval technique is demonstrated using airborne high-resolution IR measurements obtained during two field campaigns. C1 Univ Wisconsin, Cooperat Inst Meteorol Satellite Studies, Madison, WI 53706 USA. Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Yang, P (reprint author), Univ Wisconsin, Cooperat Inst Meteorol Satellite Studies, Madison, WI 53706 USA. EM pyang@ariel.met.tamu.edu RI Yang, Ping/B-4590-2011; Baum, Bryan/B-7670-2011; Ackerman, Steven/G-1640-2011; Hu, Yongxiang/K-4426-2012 OI Baum, Bryan/0000-0002-7193-2767; Ackerman, Steven/0000-0002-4476-0269; NR 51 TC 51 Z9 53 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD APR PY 2004 VL 42 IS 4 BP 842 EP 853 DI 10.1109/TGRS.2003.822752 PG 12 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 813ZW UT WOS:000220946000015 ER PT J AU Papapolymerou, J Ponchak, GE Dalton, E Bacon, A Tentzeris, MM AF Papapolymerou, J Ponchak, GE Dalton, E Bacon, A Tentzeris, MM TI Crosstalk between finite ground coplanar waveguides over polyimide layers for 3-D MMICs on Si substrates SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE coplanar waveguide (CPW); coupling; crosstalk; finite difference time domain (FDTD); finite ground coplanar (FGC) waveguide; monolithic microwave integrated circuit (MMIC); polyimide ID INTERFACE LAYER; TRANSMISSION-LINES; PASSIVE ELEMENTS; MICROSTRIP LINES; SILICON; CIRCUITS; FILTERS AB Finite-ground coplanar (FGC) waveguide lines on top of polyimide layers are frequently used to construct three-dimensional Si-SiGe monolithic microwave/millimeter-wave integrated circuits on silicon substrates. Requirements for high-density, low-cost, and compact RF front ends on silicon can lead, however, to high crosstalk between FGC lines and overall circuit performance degradation. This paper presents theoretical and experimental results and associated design guidelines for FGC line coupling on both high- and low-resistivity silicon wafers with a polyimide overlay. It is shown that a gap as small as 6 mum between two adjacent FGC lines can reduce crosstalk by at least 10 dB, that the nature of the coupling mechanism is not the same as with microstrip lines on polyimide layers, and that the coupling is not dependent on the Si resistivity. With careful layout design, isolation values of better than -30 dB can be achieved up to very high frequencies (50 GHz). C1 Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA 30332 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Papapolymerou, J (reprint author), Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA 30332 USA. NR 22 TC 10 Z9 10 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD APR PY 2004 VL 52 IS 4 BP 1292 EP 1301 DI 10.1109/TMTT.2004.825714 PG 10 WC Engineering, Electrical & Electronic SC Engineering GA 813BD UT WOS:000220881700025 ER PT J AU Thompson, DC Tantot, O Jallageas, H Ponchak, GE Tentzeris, MM Papapolymerou, J AF Thompson, DC Tantot, O Jallageas, H Ponchak, GE Tentzeris, MM Papapolymerou, J TI Characterization of liquid crystal polymer (LCP) material and transmission lines on LCP substrates from 30 to 110 GHz SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE cavity resonator; dielectric characterization; liquid crystal polymer (LCP); loss tangent; millimeter-wave frequencies; ring resonator; transmission-line loss ID MICROSTRIP; RADIATION AB Liquid crystal polymer (LCP) is a material that has gained attention as a potential high-performance microwave substrate and packaging material. This investigation uses several methods to determine the electrical properties of LCP for millimeter-wave frequencies. Microstrip ring resonators and cavity resonators are measured in order to characterize the dielectric constant (epsilon(gamma)) and loss tangent (tan delta) of LCP above 30 GHz. The measured dielectric constant is shown to be steady near 3.16, and the loss tangent stays below 0.0049. In addition, various transmission lines are fabricated on different LCP substrate thicknesses and the loss characteristics are given in decibels per centimeter from 2 to 110 GHz. Peak transmission-line losses at 110 GHz vary between 0.88-2.55 dB/cm, depending on the line type and geometry. These results show, for the first time, that LCP has excellent dielectric properties for applications extending through millimeter-wave frequencies. C1 Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA 30332 USA. Univ Limoges, Fac Sci, Inst Rech Commun Opt & Microondes, F-87060 Limoges, France. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA 30332 USA. EM Dane.Thompson@ece.gatech.edu NR 37 TC 269 Z9 269 U1 3 U2 22 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9480 EI 1557-9670 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD APR PY 2004 VL 52 IS 4 BP 1343 EP 1352 DI 10.1109/TMTT.2004.825738 PG 10 WC Engineering, Electrical & Electronic SC Engineering GA 813BD UT WOS:000220881700031 ER PT J AU Hu, XW Choi, BK Barnaby, HJ Fleetwood, DM Schrimpf, RD Lee, SC Shojah-Ardalan, S Wilkins, R Mishra, UK Dettmer, RW AF Hu, XW Choi, BK Barnaby, HJ Fleetwood, DM Schrimpf, RD Lee, SC Shojah-Ardalan, S Wilkins, R Mishra, UK Dettmer, RW TI The energy dependence of proton-induced degradation in AlGaN/GaN high electron mobility transistors SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article DE displacement damage; GaN; high electron mobility transistors; nonioizing energy loss (NIEL); proton radiation effects ID PERFORMANCE; DC AB The effects of proton irradiation at various energies are reported for AlGaN/GaN high electron mobility transistors (HEMTs). The devices exhibit little degradation when irradiated with 15-, 40-, and 105-MeV protons at fluences up to 10(13) cm(-2), and the damage completely recovers after annealing at room temperature. For 1.8-MeV proton irradiation, the drain saturation current decreases 10.6% and the maximum transconductance decreases 6.1% at a fluence of 10(12) cm(-2). The greater degradation measured at the lowest proton energy considered here is caused by the much larger nonionizing energy loss of the 1.8-MeV protons. C1 Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN 37235 USA. Univ Arizona, Dept Elect & Comp Engn, Tucson, AZ 85721 USA. Prairie View A&M Univ, NASA, Ctr Appl Radiat Res, Prairie View, TX 77446 USA. Univ Calif Santa Barbara, Dept Elect & Comp Engn, Santa Barbara, CA 93106 USA. USAF, Res Lab, Wright Patterson AFB, Wright Patterson AFB, OH 45433 USA. RP Hu, XW (reprint author), Vanderbilt Univ, Dept Elect Engn & Comp Sci, 221 Kirkland Hall, Nashville, TN 37235 USA. EM xhu@spang.com RI Schrimpf, Ronald/L-5549-2013; OI Schrimpf, Ronald/0000-0001-7419-2701; Choi, Bo K./0000-0002-4984-5958 NR 11 TC 61 Z9 64 U1 3 U2 13 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD APR PY 2004 VL 51 IS 2 BP 293 EP 297 DI 10.1109/TNS.2004.825077 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 813BV UT WOS:000220883500001 ER PT J AU Whisnant, K Iyer, RK Kalbarczyk, ZT Jones, PH Rennels, DA Some, R AF Whisnant, K Iyer, RK Kalbarczyk, ZT Jones, PH Rennels, DA Some, R TI The effects of an ARMOR-based SIFT environment on the performance and dependability of user applications SO IEEE TRANSACTIONS ON SOFTWARE ENGINEERING LA English DT Article DE software-implemented fault tolerance; distributed systems; high availability ID GROUP COMMUNICATION-SYSTEM; FAULT-TOLERANCE; ARCHITECTURE; SOFTWARE AB Few distributed software-implemented fault tolerance (SIFT) environments have been experimentally evaluated using substantial applications to show that they protect both themselves and the applications from errors. This paper presents an experimental evaluation of a SIFT environment used to oversee spaceborne applications as part of the Remote Exploration and Experimentation (REE) program at the Jet Propulsion Laboratory. The SIFT environment is built around a set of self-checking ARMOR processes running on different machines that provide error detection and recovery services to themselves and to the REE applications. An evaluation methodology is presented in which over 28,000 errors were injected into both the SIFT processes and two representative REE applications. The experiments were split into three groups of error injections, with each group successively stressing the SIFT error detection and recovery more than the previous group. The results show that the SIFT environment added negligible overhead to the application's execution time during failure-free runs. Correlated failures affecting a SIFT process and application process are possible, but the division of detection and recovery responsibilities in the SIFT environment allows it to recover from these multiple failure scenarios. Only 28 cases were observed in which either the application failed to start or the SIFT environment failed to recognize that the application had completed. Further investigations showed that assertions within the SIFT processes-coupled with object-based incremental checkpointing-were effective in preventing system failures by protecting dynamic data within the SIFT processes. C1 Sun Microsyst, San Diego, CA 92121 USA. Univ Illinois, Ctr Reliable & High Performance Comp, Urbana, IL 61801 USA. Washington Univ, Dept Comp Sci, St Louis, MO 63130 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Sun Microsyst, 9515 Towne Ctr Dr, San Diego, CA 92121 USA. EM Keith.Whisnant@sun.com; iyer@crhc.uiuc.edu; kalbarl@crhc.uiuic.edu; pjones@wustl.edu; Rennels@cs.ucla.edu; Raphael.R.Some@jpl.nasa.gov NR 38 TC 7 Z9 7 U1 0 U2 2 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0098-5589 EI 1939-3520 J9 IEEE T SOFTWARE ENG JI IEEE Trans. Softw. Eng. PD APR PY 2004 VL 30 IS 4 BP 257 EP 277 DI 10.1109/TSE.2004.1274045 PG 21 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 810YV UT WOS:000220740500005 ER PT J AU Walker, JS Volz, MP Mazuruk, K AF Walker, JS Volz, MP Mazuruk, K TI Rayleigh-Benard instability in a vertical cylinder with a rotating magnetic field SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article ID FINITE-LENGTH CYLINDER; LIQUID-METAL COLUMN; FLUID-FLOW; FREQUENCY; DRIVEN AB This paper presents a linear stability analysis for the Rayleigh-Benard convection in a finite-length, vertical cylinder with a rotating magnetic field. The vertical wall of the cylinder is adiabatic, and the planar top and bottom walls are isothermal with a higher temperature at the bottom. The stabilizing effects of the rotating magnetic field are studied for four values of the Prandtl number. Results for one Prandtl number are compared to previously published experimental results. (C) 2003 Elsevier Ltd. All rights reserved. C1 Univ Illinois, Dept Mech & Ind Engn, Urbana, IL 61801 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Walker, JS (reprint author), Univ Illinois, Dept Mech & Ind Engn, 1206 W Green St, Urbana, IL 61801 USA. EM jswalker@uiuc.edu NR 17 TC 18 Z9 18 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0017-9310 J9 INT J HEAT MASS TRAN JI Int. J. Heat Mass Transf. PD APR PY 2004 VL 47 IS 8-9 BP 1877 EP 1887 DI 10.1016/j.ijheatmasstransfer.2003.10.005 PG 11 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA 803UV UT WOS:000220256900024 ER PT J AU Xu, GW Ikegami, M Honma, S Ikeda, K Dietrich, DL Struk, PM AF Xu, GW Ikegami, M Honma, S Ikeda, K Dietrich, DL Struk, PM TI Interactive influences of convective flow and initial droplet diameter on isolated droplet burning rate SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article DE microgravity combustion; droplet burning; burning rate; flame radiation; convective flow ID SOOT FORMATION; COMBUSTION; MICROGRAVITY; HEPTANE AB In quiescent ambiences the burning rate of an isolated liquid fuel droplet varies with the droplet's initial diameter d(0) due to the close surrounding of the droplet in the lame and the subsequent strong action of flame heat, in balance with its loss to ambience, on burning. Suppressing the influence of d(0) on burning rate was recognized in this communication through burning the droplet in a forced convective flow that sweeps the flame off the droplet to weaken the action of flame heat on burning. The d(0)-dependent k(0), however, affected the correlation k = k(0) (1 + C . Re-0.5) for the burning rate in convective flows, where k(0) and k are the burning rate constants, respectively, in the equi-temperature quiescent and convective-flow ambiences, and Re is the flow's Reynolds number with respect to d(0). Different correlation constants C were acquired when using different d(0) and its corresponding k(0) to fit the correlation. In hot conditions (633 K in this article) k(0) is bigger for larger d(0), causing a smaller constant C when taking a larger d(0) for the correlation. Against this, k(0) is lower for larger d(0) in room-temperature ambiences, which resulted in the mutual compensation of the effects from k(0) and d(0) on C such that C is basically independent of the values of d(0) and k(0). Besides, the communication showed that C was larger for the gas flow with a higher temperature, revealing an increase in the effect of Re on burning with raising the gas temperature. (C) 2003 Elsevier Ltd. All rights reserved. C1 Natl Inst Adv Ind Sci & Technol AIST, Sapporo, Hokkaido 0628517, Japan. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Natl Ctr Micrograv Res, Cleveland, OH 44135 USA. RP Ikegami, M (reprint author), Natl Inst Adv Ind Sci & Technol AIST, Sapporo, Hokkaido 0628517, Japan. EM m.ikegami@aist.go.jp NR 21 TC 7 Z9 9 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0017-9310 J9 INT J HEAT MASS TRAN JI Int. J. Heat Mass Transf. PD APR PY 2004 VL 47 IS 8-9 BP 2029 EP 2035 DI 10.1016/j.ijheatmasstransfer.2003.09.035 PG 7 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA 803UV UT WOS:000220256900036 ER PT J AU Woerner, DF AF Woerner, DF TI The selection and infusion of autonomy technologies for Mars rovers SO INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS LA English DT Article; Proceedings Paper CT 1st International IEEE Symposium on Intelligent Systems CY SEP 10-12, 2002 CL VARNA, BULGARIA SP IEEE Control Syst Soc, IEEE Instrumentat & Measurement Soc, IEEE Reg 8, Auckland Univ Technol, Knowledge Engn & Discovery Res Inst, IEE IM CS SMC Joint Chapter Bulgaria, IEEE Sect Bulgaria, ICT Dev Agcy, EUNITE ID SOFTWARE AB How do you select autonomy and insure that it meets your needs and arrives for launch in a reliable form? How do you ensure that autonomy technology providers around the country meet these goals and comply with institutional practices and policies at the Jet Propulsion Laboratory (JPL) for building space-qualified, reliable systems? Answers to these questions have resulted in a process we call autonomy infusion. This article describes early work to define the process the Mars Science Laboratory (MSL) mission will use to infuse autonomy into a rover and describes attributes and evaluation criteria and their use, pertinent to autonomy technologies for Mars rovers in general. (C) 2004 Wiley Periodicals, Inc. C1 Jet Propuls Lab, Pasadena, CA 91109 USA. RP Woerner, DF (reprint author), Jet Propuls Lab, Mail Stop 301-422,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM david.f.woerner@jpl.nasa.gov NR 10 TC 0 Z9 0 U1 0 U2 0 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0884-8173 EI 1098-111X J9 INT J INTELL SYST JI Int. J. Intell. Syst. PD APR PY 2004 VL 19 IS 4 BP 353 EP 365 DI 10.1002/int.10168 PG 13 WC Computer Science, Artificial Intelligence SC Computer Science GA 802OJ UT WOS:000220172500006 ER PT J AU Hurlbert, KM Witte, LC Best, FR Kurwitz, C AF Hurlbert, KM Witte, LC Best, FR Kurwitz, C TI Scaling two-phase flows to Mars and Moon gravity conditions SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Article DE two-phase flow; scaling; partial gravity; low gravity; Mars; Moon; annular flow; stratified flow AB Hydrodynamic measurements are presented for two-phase flows in Mars and Moon gravity conditions. High accuracy pressure drop and flow rate data were obtained using dichlorodifluoromethane (i.e., R-12) as the working fluid flowing in a nominally 11.1 mm inner diameter tube. Measurements were made at Mars gravity, approximately 0.38-g, and Moon gravity, approximately 0.17-g, using NASA's KG 135 aircraft. A simplified scaling approach was developed using dimensional analysis and can be used to design an Earth-based test bed to simulate a Mars or Moon gravity prototype. For a specific geometry, a selected working fluid at a fixed temperature and pressure, and a particular flow regime condition, the pressure drop functional scaling equation is a simple, power-law relationship for the Euler number as a function of only the Froude number. The research completed Supports the use of Earth-g tests to predict the behavior of two-phase systems for Moon-g and Mars-g applications. (C) 2004 Published by Elsevier Ltd. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Univ Houston, Dept Mech Engn, Houston, TX 77204 USA. Texas A&M Univ, Dept Nucl Engn, College Stn, TX 77843 USA. RP Hurlbert, KM (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 17 TC 7 Z9 10 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD APR PY 2004 VL 30 IS 4 BP 351 EP 368 DI 10.1016/j.ijmultiphaseflow.2004.01.004 PG 18 WC Mechanics SC Mechanics GA 807YH UT WOS:000220536300001 ER PT J AU Liu, AK Hsu, MK AF Liu, AK Hsu, MK TI Internal wave study in the South China Sea using Synthetic Aperture Radar (SAR) SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article; Proceedings Paper CT Oceans from Space Venice 2000 Symposium CY OCT 09-13, 2000 CL Venice, ITALY ID SULU SEA; EVOLUTION AB Internal wave distribution maps have been compiled from more than one hundred ERS-1/2, RADARSAT and Space Shuttle SAR images in the South China Sea (SCS) from 1993 to 2000. Based on these distribution maps, most of the internal waves in the north-east part of the SCS were propagating westward. The wave crest can be as long as 200 km with an amplitude of 100 m, due to strong current from the Kuroshio branching out into the SCS. In a recent SCS internal wave study, moorings were deployed in April 1999 and 2000. Simultaneous SAR coverage from ERS-2 and RADARSAT were also collected. The ERS-2 high-resolution SAR images collected from the Taiwan ground station were processed in near real-time to coordinate the field test. SAR data are then used to compare with mooring data. SAR data and Acoustic Doppler Current Profiler (ADCP) data show internal solitons induced by the semi-diurnal tides with a wave speed of 2.4 ms(-1). C1 NASA, Oceans & Ice Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Taiwan Ocean Univ, Dept Oceanog, Chilung, Taiwan. RP Liu, AK (reprint author), NASA, Oceans & Ice Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM antony.a.liu@nasa.gov NR 7 TC 35 Z9 41 U1 1 U2 5 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD APR PY 2004 VL 25 IS 7-8 BP 1261 EP 1264 DI 10.1080/01431160310001592148 PG 4 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 779ZJ UT WOS:000189343600001 ER PT J AU Cherniawsky, JY Foreman, MGG Crawford, WR Beckley, BD AF Cherniawsky, JY Foreman, MGG Crawford, WR Beckley, BD TI Altimeter observations of sea-level variability off the west coast of North America SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article; Proceedings Paper CT Oceans from Space Venice 2000 Symposium CY OCT 09-13, 2000 CL Venice, ITALY ID OCEAN AB A combination of careful harmonic analysis and high-resolution numerical modelling of tides in altimeter data from TOPEX/Poseidon and ERS-2 satellites allows detailed calculation of seasonal and interannual variability of sea level in coastal areas of the north-east Pacific Ocean. These calculations show large changes in sea level in marginal seas during the 1997-8 El Nino and La Nina events, as well as providing information on the origin and life cycle of large anticyclonic eddies, observed to be generated off the west coast of Canada. C1 Fisheries & Oceans Canada, Inst Ocean Sci, Sidney, BC V8L 4B2, Canada. NASA, Raytheon ITSS, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Cherniawsky, JY (reprint author), Fisheries & Oceans Canada, Inst Ocean Sci, Sidney, BC V8L 4B2, Canada. EM cherniawskyj@pac.dfo-mpo.gc.ca NR 11 TC 7 Z9 8 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD APR PY 2004 VL 25 IS 7-8 BP 1303 EP 1306 DI 10.1080/01431160310001592210 PG 4 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 779ZJ UT WOS:000189343600008 ER PT J AU Di Lorenzo, E Miller, AJ Neilson, DJ Cornuelle, BD Moisan, JR AF Di Lorenzo, E Miller, AJ Neilson, DJ Cornuelle, BD Moisan, JR TI Modelling observed California Current mesoscale eddies and the ecosystem response SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article; Proceedings Paper CT Oceans from Space Venice 2000 Symposium CY OCT 09-13, 2000 CL Venice, ITALY ID COASTAL TRANSITION ZONE; CURRENT SYSTEM; DYNAMICS AB Satellite and in situ observations are used to test model dynamics for the California Current System (CCS). The model and data are combined to reconstruct the mesoscale ocean structure during a given three-week period. The resulting physical flow field is used to drive a 3D ecosystem model to interpret SeaWiFS and in situ chlorophyll-a (chl-a) variations. With this approach a more complete and consistent picture of the physical and ecosystem processes of the CCS is obtained, providing the basis for addressing fundamental questions about dynamics and predictability of the coastal ocean. C1 Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. NASA, Goddard Space Flight Ctr, Wallops Flight Facil, Wallops Isl, VA 23337 USA. RP Di Lorenzo, E (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. EM edl@ucsd.edu RI Di Lorenzo, Emanuele/E-9107-2012; Moisan, John/B-8762-2016; OI Di Lorenzo, Emanuele/0000-0002-1935-7363; Moisan, John/0000-0002-8078-8939; Cornuelle, Bruce/0000-0003-2110-3319 NR 13 TC 17 Z9 17 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD APR PY 2004 VL 25 IS 7-8 BP 1307 EP 1312 DI 10.1080/01431160310001592229 PG 6 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 779ZJ UT WOS:000189343600009 ER PT J AU Le Vine, D Koblinsky, C Pellerano, F Lagerloef, G Chao, Y Yueh, S Wilson, W AF Le Vine, D Koblinsky, C Pellerano, F Lagerloef, G Chao, Y Yueh, S Wilson, W TI A sensor to measure salinity in the open ocean from space SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article; Proceedings Paper CT Oceans from Space Venice 2000 Symposium CY OCT 09-13, 2000 CL Venice, ITALY AB The salinity of the open ocean is important for understanding ocean dynamics and for modelling energy exchange with the atmosphere. But existing data are sparse and much of the ocean is unsampled. Sea surface salinity can be measured remotely with passive microwave sensors operating near 1.4 GHz (L-band). Salinity differences have been observed from space and aircraft instruments have demonstrated that salinity can be measured with an accuracy of better than 1 psu. Sensor technology has improved sufficiently to seriously propose a satellite system to map salinity over the open oceans. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. ESR, Seattle, WA 98102 USA. NASA, Jet Prop Lab, Pasadena, CA 91109 USA. RP Le Vine, D (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM David.M.LeVine@nasa.gov NR 10 TC 4 Z9 4 U1 2 U2 4 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD APR PY 2004 VL 25 IS 7-8 BP 1313 EP 1318 DI 10.1080/01431160310001592238 PG 6 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 779ZJ UT WOS:000189343600010 ER PT J AU Gloersen, P Huang, N AF Gloersen, P Huang, N TI Interannual waves in the sea surface temperatures of the Pacific Ocean SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article; Proceedings Paper CT Oceans from Space Venice 2000 Symposium CY OCT 09-13, 2000 CL Venice, ITALY AB Various oscillatory modes of sea surface temperatures (SSTs) observed over a period of 8.8 years with the NASA Nimbus 7 Scanning Multichannel Microwave Radiometer (SMMR) and for 13 years with the NOAA Advanced Very High Resolution Radiometer (AVHRR), the latter sensing in the thermal infrared band, are described for the Pacific Ocean. The various modes are isolated by a combination of techniques designed also to accommodate non-stationary phenomena. After detrending and removing the seasonal cycle from each grid map element of the data, singular value decomposition (SVD) is used to separate the data into spatial and temporal parts to facilitate the modal analysis. Empirical Mode Decomposition is then used to separate the temporal parts of the data into approximately seven intrinsic modal functions (IMFs) for the temporal parts of the first five principal components (PCs) resulting from the SVD. A filtered time sequence of SST grids is then obtained by selecting IMFs with periods longer than 1.5 years and then reconstructing the SST grid maps from the filtered PCs. The time sequence of SMMR SSTs in the Pacific Ocean shows El Nino Southern Oscillation (ENSO) oscillations not only along the Equator, but also in both the North and South Pacific, with, in fact, even larger amplitudes than along the Equator. A similar analysis was applied to the SST record from the AVHRR instrument. During the period of overlap with the SMMR record, similarities occur in the equatorial region, but the records are by no means identical. The AVHRR SSTs do not show any strong oscillations in the South Pacific. C1 NASA, Oceans & Ice Branch, Lab Hydrospher Sci, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Gloersen, P (reprint author), NASA, Oceans & Ice Branch, Lab Hydrospher Sci, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM per.gloersen@nasa.gov NR 4 TC 1 Z9 2 U1 1 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD APR PY 2004 VL 25 IS 7-8 BP 1325 EP 1330 DI 10.1080/01431160310001592247 PG 6 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 779ZJ UT WOS:000189343600012 ER PT J AU Murtugudde, R Wang, LP Hackert, E Beauchamp, J Christian, J Busalacchi, AJ AF Murtugudde, R Wang, LP Hackert, E Beauchamp, J Christian, J Busalacchi, AJ TI Remote sensing of the Indo-Pacific region: ocean colour, sea level, winds and sea surface temperatures SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article; Proceedings Paper CT Oceans from Space Venice 2000 Symposium CY OCT 09-13, 2000 CL Venice, ITALY ID INDIAN-OCEAN AB The 1997-1998 ENSO (El Nino- Southern Oscillation) was not only the largest event of the century but also the most comprehensively observed. Satellite data were employed for ocean colour, sea level, winds, sea surface temperature (SST), and outgoing longwave radiation (OLR) were used to describe the response of the surface marine ecosystem associated with the ENSO event. Some of the large-scale anomalies in ocean colour include elevated biological activity to the north of the Equator in the Pacific coincident with lower sea levels associated with the classic ENSO-horseshoe pattern ecosystem response to the anomalous upwelling in the eastern Indian Ocean caused by the 1997-1998 dipole event, and the dramatic eastward propagating feature in the Equatorial Pacific in response to the La Nina dynamics. Ocean general circulation model (OGCM) experiments show that capturing the high-frequency wind changes is crucial for simulating the La Nina and the coupled biological physical model (OBGCM) runs clearly show that higher frequency winds are also important for capturing the mean upwelling and nutrient supply into the euphotic zone. Thus, the QuickSCAT winds are expected to play a major role in ecosystem modelling in the future. This study shows the utility of satellite data for understanding not only ocean circulation but also the coupled ecosystem variability. Moreover, it is also shown that spatio-temporal resolution of the satellite winds will directly affect the accuracy of oceanic and ecosystem simulations. C1 Univ Maryland, ESSIC, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Raytheon STSS, Lab Hydrospher Proc, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Seabrook, MD 20706 USA. RP Murtugudde, R (reprint author), Univ Maryland, ESSIC, College Pk, MD 20742 USA. EM ragu@vinsanto.essic.umd.edu RI Hackert, Eric/A-9915-2011 NR 10 TC 12 Z9 12 U1 3 U2 10 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD APR PY 2004 VL 25 IS 7-8 BP 1423 EP 1435 DI 10.1080/01431160310001592391 PG 13 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 779ZJ UT WOS:000189343600026 ER PT J AU Thomas, AC Strub, PT Carr, ME Weatherbee, R AF Thomas, AC Strub, PT Carr, ME Weatherbee, R TI Comparisons of chlorophyll variability between the four major global eastern boundary currents SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article; Proceedings Paper CT Oceans from Space Venice 2000 Symposium CY OCT 09-13, 2000 CL Venice, ITALY ID EL-NINO; OCEAN AB The first two years of SeaWiFS (Sea viewing Wide Field of view Sensor) data (1997-1999) are used to document the variability of large-scale surface chlorophyll patterns within the coastal region along the full latitudinal extent of each of the four major global eastern boundary currents; the California, Humboldt, Benguela and Canary Currents. Seasonal chlorophyll patterns are compared to coincident seasonal cycles of Ekman transport calculated from satellite scatterometer data. In all four regions, maximum chlorophyll concentrations are generally temporally and latitudinally coincident with the seasonal maximum in upwelling (offshore Ekman transport) over most of their latitudinal range, but exceptions are documented. Interannual differences are evident in each region, most notably in the two Pacific regions where the 1997-1998 chlorophyll seasonality was affected by El Nino conditions. Significant differences between previously published chlorophyll seasonality deduced from the relatively sparse coverage of the Coastal Zone Color Scanner (CZCS) and the more complete coverage of SeaWiFS in both Southern Hemisphere regions are evident. C1 Univ Maine, Sch Marine Sci, Orono, ME 04469 USA. Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91009 USA. RP Thomas, AC (reprint author), Univ Maine, Sch Marine Sci, Orono, ME 04469 USA. EM thomas@maine.edu NR 8 TC 23 Z9 24 U1 0 U2 3 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD APR PY 2004 VL 25 IS 7-8 BP 1443 EP 1447 DI 10.1080/01431160310001592418 PG 5 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 779ZJ UT WOS:000189343600028 ER PT J AU Ahumada, AJ Watson, AB AF Ahumada, AJ Watson, AB TI A spatial standard observer based on contrast energy SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract CT Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY APR 24-29, 2004 CL Ft Lauderdale, FL SP Assoc Res Vis & Ophthalmol C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI ROCKVILLE PA 12300 TWINBROOK PARKWAY, ROCKVILLE, MD 20852-1606 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD APR PY 2004 VL 45 SU 2 MA 4658 BP U492 EP U492 PG 1 WC Ophthalmology SC Ophthalmology GA 846TC UT WOS:000223338201830 ER PT J AU Ansari, RR Datiles, MB Suh, KI Reed, GF AF Ansari, RR Datiles, MB Suh, KI Reed, GF TI Dynamic Light Scattering detects molecular lens changes associated with aging as well as with cataract formation in vivo SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract CT Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY APR 24-29, 2004 CL Ft Lauderdale, FL SP Assoc Res Vis & Ophthalmol C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NEI, NIH, Bethesda, MD 20892 USA. OAI, Cleveland, OH USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI ROCKVILLE PA 12300 TWINBROOK PARKWAY, ROCKVILLE, MD 20852-1606 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD APR PY 2004 VL 45 SU 1 MA 349 BP U170 EP U170 PG 1 WC Ophthalmology SC Ophthalmology GA 846TA UT WOS:000223338000324 ER PT J AU Boeckle, S Ansari, RR Rovati, L King, JF Suh, KI AF Boeckle, S Ansari, RR Rovati, L King, JF Suh, KI TI Noninvasive monitoring of glucose concentration through the aqueous humor SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract CT Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY APR 24-29, 2004 CL Ft Lauderdale, FL SP Assoc Res Vis & Ophthalmol C1 Ohio Aerosp Inst, Cleveland, OH USA. NASA, Glenn Res Ctr, Cleveland, OH USA. Univ Modena, INFM, Natl Inst Phys Matter, I-41100 Modena, Italy. Univ Modena, Dept Informat Engn, I-41100 Modena, Italy. RI Rovati, Luigi/K-3445-2015 OI Rovati, Luigi/0000-0002-1743-3043 NR 0 TC 0 Z9 0 U1 0 U2 1 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI ROCKVILLE PA 12300 TWINBROOK PARKWAY, ROCKVILLE, MD 20852-1606 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD APR PY 2004 VL 45 SU 2 MA 4666 BP U494 EP U494 PG 1 WC Ophthalmology SC Ophthalmology GA 846TC UT WOS:000223338201840 ER PT J AU Pollonini, L Ansari, RR Pasquali, A Rovati, L Quaranta, L AF Pollonini, L Ansari, RR Pasquali, A Rovati, L Quaranta, L TI Non invasive evaluation of pigment dispersion syndrome using dynamic light scattering. SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract CT Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY APR 24-29, 2004 CL Ft Lauderdale, FL SP Assoc Res Vis & Ophthalmol C1 NASA, Natl Ctr Micrograv Res Fluids & Combust, Glenn Res Ctr, Cleveland, OH USA. Univ Modena, Dept Informat Engn, I-41100 Modena, Italy. Univ Brescia, Eye Clin, Brescia, Italy. RI quaranta, luciano/F-8922-2011; Pollonini, Luca/J-9274-2014; Rovati, Luigi/K-3445-2015 OI Pollonini, Luca/0000-0003-2955-6355; Rovati, Luigi/0000-0002-1743-3043 NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI ROCKVILLE PA 12300 TWINBROOK PARKWAY, ROCKVILLE, MD 20852-1606 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD APR PY 2004 VL 45 SU 1 MA 959 BP U369 EP U369 PG 1 WC Ophthalmology SC Ophthalmology GA 846TA UT WOS:000223338000933 ER PT J AU Simpanya, MF Ansari, RR Leverenz, VR King, JF Whitcomb, NG Giblin, FJ AF Simpanya, MF Ansari, RR Leverenz, VR King, JF Whitcomb, NG Giblin, FJ TI Aggregation of crystallins in a hyperbaric oxygen/guinea pig model for nuclear cataract: Dynamic light scattering and HPLC analyses. SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract CT Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY APR 24-29, 2004 CL Ft Lauderdale, FL SP Assoc Res Vis & Ophthalmol C1 Oakland Univ, Eye Res Inst, Rochester, MI USA. NASA, Glenn Res Ctr, Cleveland, OH USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI ROCKVILLE PA 12300 TWINBROOK PARKWAY, ROCKVILLE, MD 20852-1606 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD APR PY 2004 VL 45 SU 1 MA 1684 BP U602 EP U602 PG 1 WC Ophthalmology SC Ophthalmology GA 846TA UT WOS:000223338001643 ER PT J AU Suh, KI Ansari, RR King, JF Manuel, FK AF Suh, KI Ansari, RR King, JF Manuel, FK TI Choroidal Hemodynamics in zero gravity environment SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract CT Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY APR 24-29, 2004 CL Ft Lauderdale, FL SP Assoc Res Vis & Ophthalmol C1 NASA, Ohio Aerosp Inst, GRC, Cleveland, OH USA. NASA, Glenn Res Ctr, Cleveland, OH USA. NASA, Johnson Space Ctr, Houston, TX USA. NASA, GRC, QSS, Cleveland, OH USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI ROCKVILLE PA 12300 TWINBROOK PARKWAY, ROCKVILLE, MD 20852-1606 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD APR PY 2004 VL 45 SU 1 MA 2624 BP U974 EP U974 PG 1 WC Ophthalmology SC Ophthalmology GA 846TA UT WOS:000223338002557 ER PT J AU Lovelace, JJ Narayan, K Chik, JK Bellamy, HD Snell, EH Lindberg, U Schutt, CE Borgstahl, GEO AF Lovelace, JJ Narayan, K Chik, JK Bellamy, HD Snell, EH Lindberg, U Schutt, CE Borgstahl, GEO TI Imaging modulated reflections from a semi-crystalline state of profilin : actin crystals SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article ID INSULIN CRYSTALS; BETA-ACTIN; MICROGRAVITY AB Modulated protein crystals remain terra incognita for most crystallographers. While small-molecule crystallographers have successfully wrestled with and conquered this type of structure determination, to date no modulated macromolecular structures have been reported. Profilin: beta-actin in a modulated semi-crystalline state presents a challenge of sufficient biological significance to motivate the development of methods for the accurate collection of data on the complex diffraction pattern and, ultimately, the solution of its structure. In the present work, fine phi-sliced data collection was used to resolve the closely spaced satellite reflections from these polymorphic crystals. Image-processing methods were used to visualize these data for comparison with the original precession data. These preliminary data demonstrate the feasibility of using fine phi-slicing to collect accurately the intensities and positions of the main and satellite reflections from these modulated protein crystals. C1 987696 Nebraska Med Ctr, Eppley Inst Res Canc, Omaha, NE 68198 USA. Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Univ Calgary, Fac Med, Dept Biochem & Mol Biol, Calgary, AB T2N 4N1, Canada. Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. NASA, George C Marshall Space Flight Ctr, Struct Biol Lab, Huntsville, AL 35812 USA. Stockholm Univ, Dept Zool Cell Biol, S-10691 Stockholm, Sweden. RP 987696 Nebraska Med Ctr, Eppley Inst Res Canc, Omaha, NE 68198 USA. NR 25 TC 3 Z9 3 U1 0 U2 0 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 1600-5767 J9 J APPL CRYSTALLOGR JI J. Appl. Crystallogr. PD APR PY 2004 VL 37 BP 327 EP 330 DI 10.1107/S0021889804001773 PN 2 PG 4 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 802YN UT WOS:000220198900021 ER PT J AU Wang, Z Sassen, K Whiteman, DN Demoz, BB AF Wang, Z Sassen, K Whiteman, DN Demoz, BB TI Studying altocumulus with ice virga using ground-based active and passive remote sensors SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID MIXED-PHASE CLOUDS; HIGHLY SUPERCOOLED ALTOCUMULUS; GENERAL-CIRCULATION MODEL; RADIATIVE PROPERTIES; WATER-VAPOR; MICROWAVE RADIOMETER; MULTIPLE-SCATTERING; RADAR MEASUREMENTS; CIRRUS CLOUDS; RAMAN LIDAR AB Mixed-phase clouds are still poorly understood, though studies have indicated that their parameterization in general circulation models is critical for climate studies. Most of the knowledge of mixed-phase clouds has been gained from in situ measurements, but reliable remote sensing algorithms to study mixed-phase clouds extensively are lacking. A combined active and passive remote sensing approach for studying supercooled altocumulus with ice virga, using multiple remote sensor observations, is presented. Precipitating altocumulus clouds are a common type of mixed-phase clouds, and their easily identifiable structure provides a simple scenario to study mixed-phase clouds. First, ice virga is treated as an independent ice cloud, and an existing lidar-radar algorithm to retrieve ice water content and general effective size profiles is applied. Then, a new iterative approach is used to retrieve supercooled water cloud properties by minimizing the difference between atmospheric emitted radiance interferometer (AERI)-observed radiances and radiances, calculated using the discrete-ordinate radiative transfer model at 12 selected wavelengths. Case studies demonstrate the capabilities of this approach in retrieving radiatively important microphysical properties to characterize this type of mixed-phase cloud. The good agreement between visible optical depths derived from lidar measurement and those estimated from retrieved liquid water path and effective radius provides a closure test for the accuracy of mainly AERI-based supercooled water cloud retrieval. C1 NASA, UMBC GEST Ctr, Mesoscale Atmospher Proc Branch, GSFC, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Univ Alaska Fairbanks, Inst Geophys, Fairbanks, AK 99775 USA. RP Wang, Z (reprint author), NASA, UMBC GEST Ctr, Mesoscale Atmospher Proc Branch, GSFC, Code 912,Bldg 33,Room A417, Greenbelt, MD 20771 USA. EM zhien@agnes.gsfc.nasa.gov RI Wang, Zhien/F-4857-2011; Demoz, Belay/N-4130-2014 NR 41 TC 36 Z9 36 U1 1 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD APR PY 2004 VL 43 IS 3 BP 449 EP 460 DI 10.1175/1520-0450(2004)043<0449:SAWIVU>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 807CF UT WOS:000220478900004 ER PT J AU Fisher, BL AF Fisher, BL TI Climatological validation of TRMM TMI and PR monthly rain products over Oklahoma SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID MEASURING MISSION TRMM; TROPICAL RAINFALL; SAMPLING ERRORS; PRECIPITATION RADAR; PROFILING ALGORITHM; OCEANIC RAINFALL; STOCHASTIC-MODEL; UNITED-STATES; SATELLITE; TIME AB This paper reports the results from a regional validation study of monthly precipitation products generated from sensor measurements aboard the Tropical Rainfall Measuring Mission (TRMM) satellite. The study analyzed 4 yr of precipitation estimates (1998 - 2001) produced from data collected by the TRMM Microwave Imager (TMI) and the precipitation radar ( PR) and compared them with corresponding estimates computed using 5-min rain accumulations from 66 rain gauges in the Oklahoma Mesonet. The applied methodology estimated bulk climate-scale sampling and retrieval errors and biases for the TMI and PR at two areal resolutions: 1degrees x 1degrees and 2degrees x 5degrees. The approach taken in this study generated two gauge-inferred gridded estimates of monthly precipitation over the study period: 1) G(0), which was computed by performing a complete integration of the monthly gauge time series, and 2) G(S), which consisted of gauge-inferred rain rates subsampled to TRMM overpasses at a gridded resolution of 1degrees x 1degrees, with monthly precipitation estimates derived from the bulk statistics collected during each month of the study. The variable G(S) depends on the areal swath of each sensor and so yields two sensor-dependent estimates of gauge-inferred precipitation (G(TMI), G(PR)). The advantage of this approach is that it allows for the separation of retrieval and sampling errors, because the subsampled gauge estimates include the temporal sampling errors associated with the satellite sampling. The overall random sampling and retrieval errors for the PR exceeded the TMI errors for the study period, but the PR showed a greater reduction in the errors when the scale was increased to 2degrees x 5degrees. Annual coefficients of variation were also generally lower for the PR than the TMI at this scale. This result was consistent with PR retrieval biases, which were positive over all 4 yr, exceeding the TMI biases in every year of the study. C1 NASA, Lab Atmospheres & Sci Syst & Applicat, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fisher, BL (reprint author), NASA, Lab Atmospheres & Sci Syst & Applicat, Goddard Space Flight Ctr, Code 912-1,Bldg 22,Room 166, Greenbelt, MD 20771 USA. EM fisher@radar.gsfc.nasa.gov NR 35 TC 25 Z9 25 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD APR PY 2004 VL 43 IS 3 BP 519 EP 535 DI 10.1175/1520-0450(2004)043<0519:CVOTTA>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 807CF UT WOS:000220478900010 ER PT J AU Grecu, M Olson, WS Anagnostou, EN AF Grecu, M Olson, WS Anagnostou, EN TI Retrieval of precipitation profiles from multiresolution, multifrequency active and passive microwave observations SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID RAINDROP SIZE DISTRIBUTION; RAINFALL ESTIMATION; MELTING-LAYER; RADAR; ALGORITHM; RADIOMETER; CLOUD; ATTENUATION; EVAPORATION; EVOLUTION AB In this study, a technique for estimating vertical profiles of precipitation from multifrequency, multiresolution active and passive microwave observations is investigated. The technique is applicable to the Tropical Rainfall Measuring Mission (TRMM) observations, and it is based on models that simulate high-resolution brightness temperatures as functions of observed reflectivity profiles and a parameter related to the raindrop size distribution. The modeled high-resolution brightness temperatures are used to determine normalized brightness temperature polarizations at the microwave radiometer resolution. An optimal estimation procedure is employed to minimize the differences between the simulated and observed normalized polarizations by adjusting the drop size distribution parameter. The impact of other unknowns that are not independent variables in the optimal estimation, but affect the retrievals, is minimized through statistical parameterizations derived from cloud model simulations. The retrieval technique is investigated using TRMM observations collected during the Kwajalein Experiment (KWAJEX). These observations cover an area extending from 5degrees to 12degreesN latitude and from 166degrees to 172degreesE longitude from July to September 1999 and are coincident with various ground-based observations, facilitating a detailed analysis of the retrieved precipitation. Using the method developed in this study, precipitation estimates consistent with both the passive and active TRMM observations are obtained. Various parameters characterizing these estimates, that is, the rain rate, precipitation water content, drop size distribution intercept, and the mass-weighted mean drop diameter, are in good qualitative agreement with independent experimental and theoretical estimates. Combined rain estimates are, in general, higher than the official TRMM precipitation radar (PR)-only estimates for the area and the period considered in the study. Ground-based precipitation estimates, derived from an analysis of rain gauge and ground radar data, are in better agreement with the combined estimates than with the TRMM PR-only estimates, which suggests that information useful for improving the radar-only estimates is contained in the brightness temperature data. C1 NASA, GEST UMBC, Goddard Space Flight Ctr, Greenbelt, MD 20770 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. Univ Connecticut, Dept Civil & Environm Engn, Storrs, CT USA. RP Grecu, M (reprint author), NASA, GEST UMBC, Goddard Space Flight Ctr, Code 912-0, Greenbelt, MD 20770 USA. EM grecu@agnes.gsfc.nasa.gov NR 31 TC 36 Z9 36 U1 1 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD APR PY 2004 VL 43 IS 4 BP 562 EP 575 DI 10.1175/1520-0450(2004)043<0562:ROPPFM>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 814BW UT WOS:000220951200003 ER PT J AU Walsh, BM Barnes, NP Petros, M Yu, JR Singh, UN AF Walsh, BM Barnes, NP Petros, M Yu, JR Singh, UN TI Spectroscopy and modeling of solid state lanthanide lasers: Application to trivalent Tm3+ and Ho3+ in YLiF4 and LuLiF4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID RARE-EARTH IONS; CRYSTAL-FIELD ANALYSIS; END-PUMPING TECHNIQUE; SINGLE-CRYSTALS; ENERGY-TRANSFER; OPTICAL APPLICATIONS; LATTICE-VIBRATIONS; ROOM-TEMPERATURE; EXCITED STATES; PUMPED HO AB Lanthanide series ions are considered in the context of acquiring spectroscopic parameters and their application to modelling of quasifour-level lasers. Tm:Ho codoped crystals of YLiF4 (YLF) and the isomorphs LuLiF4 (LuLF) and GdLiF4 (GdLF) as 2.0 mum lasers are used for illustration of the experimental and theoretical techniques presented here. While these materials have similar physical properties, they differ in the strength of the crystal field at the site of optically active lanthanide dopant ions such as Tm3+ and Ho3+. This is due in part to the size of the Lu3+, Y3+, and Gd3+ ions, which comprise part of the host lattice, but ionicity plays a role as well. This selection of lanthanide: host materials provides a useful basis on which to assess laser materials with regards to changes in the strength of the crystal field at the dopant ion site. It is demonstrated that Tm:Ho:LuLF has a larger crystal field splitting than Tm:Ho:YLF and Tm:Ho:GdLF, leading to smaller thermal populations in the Ho lower laser level. To assess this effect quantitatively, the energy levels of the first ten manifolds in Ho:LuLF have been determined. Measurement of Ho:XLiF4 (X=Y,Lu,Gd) emission cross sections at 2.0 mum, Tm:XLiF4 pump absorption cross sections around 0.78 mum, manifold to manifold decay times and energy transfer parameters in Tm:Ho:XLiF4 systems are also determined to provide a consistent set of parameters to use in laser modeling. The techniques presented here are applicable to any lanthanide series ion in a crystalline host. A theoretical laser model has been developed that is easily adapted to any lanthanide ion in a crystal host. The model is used to predict diode side-pumped laser performance of Tm:Ho:LuLF and Tm:Ho:YLF using input parameters determined from the spectroscopy presented here. An explanation is presented for the improved performance of Tm:Ho:LuLF over Tm:Ho:YLF by modeling the laser. A demonstration that small changes in lower laser thermal population can substantially alter laser performance is noted, an effect that has not been fully appreciated previously. (C) 2004 American Institute of Physics. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Sci & Technol Corp, Hampton, VA 23666 USA. RP NASA, Langley Res Ctr, Hampton, VA 23681 USA. EM brian.m.walsh@nasa.gov NR 52 TC 104 Z9 105 U1 3 U2 27 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD APR 1 PY 2004 VL 95 IS 7 BP 3255 EP 3271 DI 10.1063/1.1649808 PG 17 WC Physics, Applied SC Physics GA 805BV UT WOS:000220342700003 ER PT J AU Sharma, SP Cruden, BA Rao, MVVS Bolshakov, AA AF Sharma, SP Cruden, BA Rao, MVVS Bolshakov, AA TI Analysis of emission data from O-2 plasmas used for microbe sterilization SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INDUCTIVELY-COUPLED PLASMAS; LANGMUIR PROBE MEASUREMENTS; LASER-INDUCED FLUORESCENCE; OPTICAL-EMISSION; DEINOCOCCUS-RADIODURANS; GLOW-DISCHARGES; ELECTRON-IMPACT; GAS PLASMA; TEMPERATURE; PRESSURE AB In order to study the sterilization capabilities of radio frequency driven low pressure oxygen plasmas, the radiative emission was recorded at various pressures and input powers. A distinct transition from the bright mode (primarily inductively coupled) to a dim mode (primarily capacitively coupled) was observed as the pressure was increased and/or the power decreased. The data was further analyzed to estimate the electron temperature, rotational and vibrational temperatures, and various species concentrations. Based on the diffusion and rovibrational relaxation times, it is concluded that the rotational temperatures can be assumed to be in equilibrium with the translational temperature. The ions are produced "hot" and have little time to get equilibrated with the translational temperature. It is further determined that in the bright mode, which is more effective in microbe sterilization, the translational/rotational temperatures are in the 650-850 K range, the electron temperatures are low (3.5-4.5 eV), and the concentrations of atomic O and atomic metastables are at 1 order of magnitude higher than in the dim mode. (C) 2004 American Institute of Physics. C1 NASA, Ames Res Ctr, Plasma Res Lab, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, ELORET, Moffett Field, CA 94035 USA. RP Sharma, SP (reprint author), NASA, Ames Res Ctr, Plasma Res Lab, Moffett Field, CA 94035 USA. EM surendra.p.sharma@nasa.gov RI Bol'shakov, Alexander/A-9258-2015 OI Bol'shakov, Alexander/0000-0002-6034-7079 NR 53 TC 10 Z9 10 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 1 PY 2004 VL 95 IS 7 BP 3324 EP 3333 DI 10.1063/1.1650921 PG 10 WC Physics, Applied SC Physics GA 805BV UT WOS:000220342700011 ER PT J AU Koshak, WJ Solakiewicz, RJ Blakeslee, RJ Goodman, SJ Christian, HJ Hall, JM Bailey, JC Krider, EP Bateman, MG Boccippio, DJ Mach, DM McCaul, EW Stewart, MF Buechler, DE Petersen, WA Cecil, DJ AF Koshak, WJ Solakiewicz, RJ Blakeslee, RJ Goodman, SJ Christian, HJ Hall, JM Bailey, JC Krider, EP Bateman, MG Boccippio, DJ Mach, DM McCaul, EW Stewart, MF Buechler, DE Petersen, WA Cecil, DJ TI North Alabama Lightning Mapping Array (LMA): VHF source retrieval algorithm and error analyses SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB Two approaches are used to characterize how accurately the north Alabama Lightning Mapping Array (LMA) is able to locate lightning VHF sources in space and time. The first method uses a Monte Carlo computer simulation to estimate source retrieval errors. The simulation applies a VHF source retrieval algorithm that was recently developed at the NASA Marshall Space Flight Center (MSFC) and that is similar, but not identical to, the standard New Mexico Tech retrieval algorithm. The second method uses a purely theoretical technique (i.e., chi-squared Curvature Matrix Theory) to estimate retrieval errors. Both methods assume that the LMA system has an overall rms timing error of 50 ns, but all other possible errors ( e. g., anomalous VHF noise sources) are neglected. The detailed spatial distributions of retrieval errors are provided. Even though the two methods are independent of one another, they nevertheless provide remarkably similar results. However, altitude error estimates derived from the two methods differ ( the Monte Carlo result being taken as more accurate). Additionally, this study clarifies the mathematical retrieval process. In particular, the mathematical difference between the first-guess linear solution and the Marquardt-iterated solution is rigorously established thereby explaining why Marquardt iterations improve upon the linear solution. C1 NASA, Dept Earth Sci, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Chicago State Univ, Chicago, IL USA. Comp Sci Corp, Huntsville, AL USA. Raytheon ITSS, Huntsville, AL USA. Univ Arizona, Tucson, AZ USA. NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, Huntsville, AL 35812 USA. Univ Alabama, Huntsville, AL 35899 USA. RP Koshak, WJ (reprint author), NASA, Dept Earth Sci, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. EM william.koshak@nasa.gov NR 7 TC 43 Z9 45 U1 4 U2 8 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD APR PY 2004 VL 21 IS 4 BP 543 EP 558 DI 10.1175/1520-0426(2004)021<0543:NALMAL>2.0.CO;2 PG 16 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 809PL UT WOS:000220648500002 ER PT J AU Duffy, DG AF Duffy, DG TI The application of Hilbert-Huang transforms to meteorological datasets SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID EMPIRICAL MODE DECOMPOSITION; TIME FOURIER-ANALYSIS; SERIES ANALYSIS; VARIABILITY; PRESSURE AB Recently a new spectral technique has been developed for the analysis of aperiodic signals from nonlinear systems - the Hilbert- Huang transform. It is shown how this transform can be used to discover synoptic and climatic features: For sea level data, the transforms capture the oceanic tides as well as variations in precipitation patterns. In the case of solar radiation, variations in the diurnal and seasonal cycles are observed. Finally, from barographic data, the Hilbert- Huang transform reveals the passage of extratropical cyclones, fronts, and troughs. Thus, this technique can detect signals on synoptic to interannual time scales. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP NASA, Goddard Space Flight Ctr, Code 912, Greenbelt, MD 20771 USA. EM duffy@agnes.gsfc.nasa.gov NR 23 TC 38 Z9 43 U1 0 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 EI 1520-0426 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD APR PY 2004 VL 21 IS 4 BP 599 EP 611 DI 10.1175/1520-0426(2004)021<0599:TAOHTT>2.0.CO;2 PG 13 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 809PL UT WOS:000220648500006 ER PT J AU Lieberman, RS Oberheide, J Hagan, ME Remsberg, EE Gordley, LL AF Lieberman, RS Oberheide, J Hagan, ME Remsberg, EE Gordley, LL TI Variability of diurnal tides and planetary waves during November 1978-May 1979 SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article; Proceedings Paper CT International Symposium on the Dynamics and Chemistry of the MLT Region CY OCT 04-08, 2002 CL Foz do Iguacu, BRAZIL SP Sci Comm Solar Terrestrial Phys, Soc Brasileira Geofis, CAPES DE diurnal; tides; planetary waves; middle atmosphere dynamics ID LATENT-HEAT RELEASE; EQUATORIAL MIDDLE ATMOSPHERE; LIMB INFRARED MONITOR; MIGRATING SOLAR TIDES; TIDAL VARIABILITY; SATELLITE-OBSERVATIONS; 12-HOUR OSCILLATION; UPPER THERMOSPHERE; CIRCULATION MODEL; 30 KILOMETERS AB Nonlinear interactions between stationary waves and the migrating tides have been proposed as possible sources of nonmigrating tides in the middle and upper atmosphere. The objective of this study is to increase observational support for these processes. We examine the evolution of stationary planetary waves and nonmigrating diurnal tides in the lower mesosphere during November 1978-May 1979, based on a newly released, version 6 of the Nimbus 7 LIMS dataset. Planetary wavenumber one is large and variable during the Northern hemisphere winter months, reaching peak amplitude in the lower mesosphere between 20 and 30 January. This behavior is accompanied by rapid amplification of nonmigrating diurnal tides with zonal wavenumbers zero and two. These components correspond to product waves generated by interaction between the migrating diurnal tide and the stationary wave. The westward traveling zonal wavenumber two diurnal tide is dominant at tropical latitudes, in accordance with theoretical studies. The correlation between the nonmigrating tide and stationary wavenumber one is highest when the stationary wave penetrates to subtropical latitudes. (C) 2004 Elsevier Ltd. All rights reserved. C1 NW Res Associates Inc, Colorado Res Associates Div, Boulder, CO 80301 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. G&A Tech Software Inc, Newport News, VA USA. RP Lieberman, RS (reprint author), NW Res Associates Inc, Colorado Res Associates Div, 3380 Mitchell Lane, Boulder, CO 80301 USA. EM ruth@co-ra.com RI Hagan, Maura/C-7200-2008; Oberheide, Jens/C-6156-2011 OI Hagan, Maura/0000-0002-8866-7429; Oberheide, Jens/0000-0001-6721-2540 NR 47 TC 51 Z9 52 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD APR-JUN PY 2004 VL 66 IS 6-9 BP 517 EP 528 DI 10.1016/j.jastp.2004.01.006 PG 12 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 824WC UT WOS:000221716900009 ER PT J AU Wang, DY Huo, WM Dateo, CE Schwenke, DW Stallcop, JR AF Wang, DY Huo, WM Dateo, CE Schwenke, DW Stallcop, JR TI Quantum study of the N+N-2 exchange reaction: State-to-state reaction probabilities, initial state selected probabilities, Feshbach resonances, and product distributions SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POTENTIAL-ENERGY SURFACE; REACTION DYNAMICS; RATE CONSTANTS; COLLISIONS; SCATTERING; NITROGEN; ATOMS; H3 AB We report a detailed three-dimensional time-dependent quantum dynamics study of the state-to-state N+N-2 exchange scattering in the 2.1-3.2 eV range using a recently developed ab initio potential energy surface (PES). The reactive flux arrives at the dividing surface in the asymptotic product region in a series of six packets, instead of a single packet. Further study shows that these features arise from the "Lake Eyring" region of the PES, a region with a shallow well between two transition states. Trappings due to Feshbach resonances are found to be the major cause of the time delay. A detailed analysis of the Feshbach resonance features is carried out using an L-2 calculation of the metastable states in the "Lake Eyring" region. Strong resonance features are found in the state-to-state and initial state selected reaction probabilities. The metastable states with bending motions and/or bending coupled with stretching motions are found to be the predominant source of the resonance structure. Initial state selected reaction probabilities further indicate that the lifetimes of the metastable states with bending motions in the "Lake Eyring" region are longer than those of states with stretching motions and thus dominate the reactive resonances. Resonance structures are also visible in some of the integral cross sections and should provide a means for future experimental observation of the resonance behavior. A study of the final rotational distributions shows that, for the energy range studied here, the final products are distributed toward high-rotational states. Final vibrational distributions at the temperatures 2000 and 10 000 K are also reported. (C) 2004 American Institute of Physics. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Wang, DY (reprint author), NASA, Ames Res Ctr, MS T27B-1, Moffett Field, CA 94035 USA. EM dywang@nas.nasa.gov RI schwenke, david/I-3564-2013 NR 34 TC 22 Z9 22 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 1 PY 2004 VL 120 IS 13 BP 6041 EP 6050 DI 10.1063/1.1650834 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 803ZN UT WOS:000220269100023 PM 15267487 ER PT J AU Schneider, DP Steig, EJ Comiso, JC AF Schneider, DP Steig, EJ Comiso, JC TI Recent climate variability in Antarctica from satellite-derived temperature data SO JOURNAL OF CLIMATE LA English DT Article ID LOW-FREQUENCY VARIABILITY; SEA-SURFACE TEMPERATURE; NCEP-NCAR REANALYSIS; SOUTHERN-HEMISPHERE; SEMIANNUAL OSCILLATION; EAST ANTARCTICA; ICE CORE; CIRCULATION; TRENDS; MODES AB Recent Antarctic climate variability on month-to-month to interannual time scales is assessed through joint analysis of surface temperatures from satellite thermal infrared observations (T-IR) and passive microwave brightness temperatures (T-B). Although T-IR data are limited to clear-sky conditions and T-B data are a product of the temperature and emissivity of the upper; 1 m of snow, the two datasets share significant covariance. This covariance is largely explained by three empirical modes, which illustrate the spatial and temporal variability of Antarctic surface temperatures. The T-B variations are damped compared to T-IR variations, as determined by the period of the temperature forcing and the microwave emission depth; however, microwave emissivity does not vary significantly in time. Comparison of the temperature modes with Southern Hemisphere (SH) 500-hPa geopotential height anomalies demonstrates that Antarctic temperature anomalies are predominantly controlled by the principal patterns of SH atmospheric circulation. The leading surface temperature mode strongly correlates with the Southern Annular Mode (SAM) in geopotential height. The second temperature mode reflects the combined influences of the zonal wavenumber-3 and Pacific - South American (PSA) patterns in 500-hPa height on month-to-month time scales. ENSO variability projects onto this mode on interannual time scales, but is not by itself a good predictor of Antarctic temperature anomalies. The third temperature mode explains winter warming trends, which may be caused by blocking events, over a large region of the East Antarctic plateau. These results help to place recent climate changes in the context of Antarctica's background climate variability and will aid in the interpretation of ice core paleoclimate records. C1 Univ Washington, Dept Earth & Space Sci, Seattle, WA 98195 USA. NASA, Goddard Space Flight Ctr, Lab Hydrospher Proc, Greenbelt, MD 20771 USA. RP Schneider, DP (reprint author), Univ Washington, Dept Earth & Space Sci, Box 351310, Seattle, WA 98195 USA. EM schneidd@u.washington.edu RI Schneider, David/E-2726-2010; Steig, Eric/G-9088-2015 OI Steig, Eric/0000-0002-8191-5549 NR 56 TC 66 Z9 71 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD APR PY 2004 VL 17 IS 7 BP 1569 EP 1583 DI 10.1175/1520-0442(2004)017<1569:RCVIAF>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809AN UT WOS:000220609700010 ER PT J AU Minnis, P Ayers, JK Palikonda, R Phan, D AF Minnis, P Ayers, JK Palikonda, R Phan, D TI Contrails, cirrus trends, and climate SO JOURNAL OF CLIMATE LA English DT Article ID UPPER TROPOSPHERE; GLOBAL DISTRIBUTION; TEMPERATURE TRENDS; RELATIVE-HUMIDITY; UNITED-STATES; CLOUD; RADIOSONDES; NUCLEATION; SATELLITE AB Rising global air traffic and its associated contrails have the potential for affecting climate via radiative forcing. Current estimates of contrail climate effects are based on coverage by linear contrails that do not account for spreading and, therefore, represent the minimum impact. The maximum radiative impact is estimated by assuming that long-term trends in cirrus coverage are due entirely to air traffic in areas where humidity is relatively constant. Surface observations from 1971 to 1995 show that cirrus increased significantly over the northern oceans and the United States while decreasing over other land areas except over western Europe where cirrus coverage was relatively constant. The surface observations are consistent with satellite-derived trends over most areas. Land cirrus trends are positively correlated with upper-tropospheric (300 hPa) humidity (UTH), derived from the National Centers for Environmental Prediction (NCEP) analyses, except over the United States and western Europe where air traffic is heaviest. Over oceans, the cirrus trends are negatively correlated with the NCEP relative humidity suggesting some large uncertainties in the maritime UTH. The NCEP UTH decreased dramatically over Europe while remaining relatively steady over the United States, thereby permitting an assessment of the cirrus-contrail relationship over the United States. Seasonal cirrus changes over the United States are generally consistent with the annual cycle of contrail coverage and frequency lending additional evidence to the role of contrails in the observed trend. It is concluded that the U. S. cirrus trends are most likely due to air traffic. The cirrus increase is a factor of 1.8 greater than that expected from current estimates of linear contrail coverage suggesting that a spreading factor of the same magnitude can be used to estimate the maximum effect of the contrails. From the U. S. results and using mean contrail optical depths of 0.15 and 0.25, the maximum contrail-cirrus global radiative forcing is estimated to be 0.006-0.025 W m(-2) depending on the radiative forcing model. Using results from a general circulation model simulation of contrails, the cirrus trends over the United States are estimated to cause a tropospheric warming of 0.2degrees-0.3degreesC decade(-1), a range that includes the observed tropospheric temperature trend of 0.27degreesC decade(-1) between 1975 and 1994. The magnitude of the estimated surface temperature change and the seasonal variations of the estimated temperature trends are also in good agreement with the corresponding observations. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Analyt Serv & Mat Inc, Hampton, VA 23666 USA. RP Minnis, P (reprint author), NASA, Langley Res Ctr, MS 420, Hampton, VA 23681 USA. EM p.minnis@nasa.gov RI Minnis, Patrick/G-1902-2010 OI Minnis, Patrick/0000-0002-4733-6148 NR 44 TC 97 Z9 99 U1 1 U2 9 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD APR PY 2004 VL 17 IS 8 BP 1671 EP 1685 DI 10.1175/1520-0442(2004)017<1671:CCTAC>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 811WQ UT WOS:000220802400005 ER PT J AU Wu, LG Wang, B AF Wu, LG Wang, B TI Assessing impacts of global warming on tropical cyclone tracks SO JOURNAL OF CLIMATE LA English DT Article ID HURRICANE BETA-DRIFT; ENVIRONMENTAL FLOW; VERTICAL SHEAR; CLIMATE-CHANGE; VORTEX MOTION; MEAN FLOW; MODEL; VARIABILITY; EVOLUTION; VORTICES AB A new approach is proposed to assess the possible impacts of the global climate change on tropical cyclone (TC) tracks in the western North Pacific (WNP) basin. The idea is based on the premise that the future change of TC track characteristics is primarily determined by changes in large-scale environmental steering flows and in formation locations. It is demonstrated that the main characteristics of the current climatology of TC tracks can be derived from the climatological mean velocity field of TC motion by using a trajectory model. The climatological mean velocity of TC motion, composed of the large-scale steering and beta drift, is determined on each grid of the basin. The mean large-scale steering flow is computed from the NCEP-NCAR reanalysis for the current climate state. The mean beta drift is estimated from the best-track data by removing the steering flow. The derived mean beta drift agrees well with the results of previous observational and numerical studies in terms of its direction and magnitude. The approach is applied to assessing the potential impacts of global warming on TC tracks in the WNP. The possible changes in the large-scale steering flows are taken from the output wind fields of two Geophysical Fluid Dynamics Laboratory (GFDL) global warming experiments and possible changes in the TC formation locations are considered by shifting the formation locations as a whole. The GFDL experiments suggested that the changes in the future large-scale steering flows are dominated by the easterly anomalies in the Tropics and westerly anomalies in the midlatitudes with the enhanced northward component during the period of 2030-59. Based on the assessments using two different ways to reduce climate model biases, the prevailing TC tracks shift slightly southwestward during the period of 2000-29, but northeastward during the period of 2030-59. More TCs will take a recurving track and move northeastward during the period of 2030-59. The El Nino-like climate change predicted in many climate models can significantly enhance the track changes if the TC formation locations in the WNP shift eastward as a whole. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth & Technol Ctr, Baltimore, MD 21228 USA. Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Dept Meteorol, Honolulu, HI 96822 USA. RP Wu, LG (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 912, Greenbelt, MD 20771 USA. EM liguang@agnes.gsfc.nasa.gov NR 35 TC 79 Z9 95 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD APR PY 2004 VL 17 IS 8 BP 1686 EP 1698 DI 10.1175/1520-0442(2004)017<1686:AIOGWO>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 811WQ UT WOS:000220802400006 ER PT J AU Tong, MT Halliwell, I Ghosn, LJ AF Tong, MT Halliwell, I Ghosn, LJ TI A computer code for gas turbine engine weight and disk life estimation SO JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 47th International Gas Turbine and Aeroengine Congress and Exhibition CY JUN 03-06, 2002 CL AMSTERDAM, NETHERLANDS AB Reliable engine-weight estimation at the conceptual design stage is critical to the development of new aircraft engines. It helps to identify the best engine concept amongst several candidates. In this paper the major enhancements to NASA's engine-weight estimate computer code (WATE) are described. These enhancements include the incorporation of improved weight-calculation routines for the compressor and turbine disks using the finite difference technique. Furthermore, the stress distribution for various disk geometries was also incorporated, for a life-prediction module to calculate disk life. A material database, consisting of the material data of most of the commonly used aerospace materials, has also been incorporated into WATE. Collectively, these enhancements provide a more realistic and systematic way to calculate the engine weight. They also provide additional insight into the design tradeoff between engine life and engine weight. To demonstrate the new capabilities, the enhanced WATE code is used to perform all engine weight/life tradeoff assessment on a production aircraft engine. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Modern Technol Corp, Cleveland, OH USA. Ohio Aerosp Inst, Brookpark, OH USA. RP Tong, MT (reprint author), NASA, Glenn Res Ctr, 21000 Brook Pk Rd,Mail Stop 60-7, Cleveland, OH 44135 USA. NR 12 TC 10 Z9 10 U1 1 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0742-4795 J9 J ENG GAS TURB POWER JI J. Eng. Gas. Turbines Power-Trans. ASME PD APR PY 2004 VL 126 IS 2 BP 265 EP 270 DI 10.1115/1.1691980 PG 6 WC Engineering, Mechanical SC Engineering GA 831KG UT WOS:000222192700008 ER PT J AU Moraru, C Logendra, L Lee, TC Janes, H AF Moraru, C Logendra, L Lee, TC Janes, H TI Characteristics of 10 processing tomato cultivars grown hydroponically for the NASA Advanced Life Support (ALS) Program SO JOURNAL OF FOOD COMPOSITION AND ANALYSIS LA English DT Article DE processing tomato; Lycopersicon esculentum; cultivar screening; quality evaluation; hydroponics; ebb and flood; harvest index; advanced life support; lycopene ID PLASMA AB Ten hydroponically grown processing tomato cultivars were characterized, in order to identify the most appropriate cultivar for direct consumption and processing for NASA's Advanced Life Support (ALS) Program. Tomatoes were grown under semi-controlled environmental conditions at a Rutgers University greenhouse. The performance of each cultivar was evaluated using growth and yield indicators, physical/chemical indexes and sensory testing. Most quality indexes showed significant differences between cultivars, although their values remained in the typical ranges for processing tomatoes. The primary use of this information is to assist NASA in the decision on the most appropriate processing tomato cultivar for ALS use. The cultivar selected was SUN 6177, which ranked best in growth/yield and physical/chemical characteristics and in sensory attributes, and was second in consumer liking. The data generated in this study is of equal interest for comparing hydroponically grown fresh consumption and processing tomatoes, as well as for evaluating the effects of hydroponic growth on processing tomatoes. (C) 2003 Elsevier Ltd. All rights reserved. C1 Rutgers State Univ, Dept Food Sci, NASA, Specialized Ctr Res & Training, New Brunswick, NJ 08901 USA. Rutgers State Univ, Ctr Adv Food Technol, New Brunswick, NJ 08903 USA. Rutgers State Univ, Dept Plant Sci, New Brunswick, NJ 08901 USA. RP Lee, TC (reprint author), Rutgers State Univ, Dept Food Sci, NASA, Specialized Ctr Res & Training, 65,Dudley Rd, New Brunswick, NJ 08901 USA. EM lee@aesop.rutgers.edu NR 32 TC 18 Z9 20 U1 2 U2 14 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0889-1575 J9 J FOOD COMPOS ANAL JI J. Food Compos. Anal. PD APR PY 2004 VL 17 IS 2 BP 141 EP 154 DI 10.1016/j.jfca.2003.08.003 PG 14 WC Chemistry, Applied; Food Science & Technology SC Chemistry; Food Science & Technology GA 804WX UT WOS:000220329900003 ER PT J AU Cakmur, RV Miller, RL Torres, O AF Cakmur, RV Miller, RL Torres, O TI Incorporating the effect of small-scale circulations upon dust emission in an atmospheric general circulation model SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Review DE dust modeling ID CONVECTIVE BOUNDARY-LAYER; AEROSOL OPTICAL DEPTH; LAST GLACIAL MAXIMUM; MINERAL DUST; WIND-SPEED; SIZE-DISTRIBUTION; SAHARAN DUST; GISS-GCM; 3-DIMENSIONAL SIMULATION; INTERANNUAL VARIABILITY AB [1] Realistic simulation of dust emission in an atmospheric general circulation model (AGCM) is inhibited by the model's coarse resolution compared to the scale of the circulations observed to mobilize dust. We construct a probability distribution of wind speed within each grid box that depends upon the speed explicitly calculated by the AGCM and the magnitude of fluctuations about this speed. This magnitude is calculated by incorporating information from the AGCM's parameterizations of the planetary boundary layer along with dry and moist convection. Emission depends on the fraction of the wind speed distribution above the threshold value. As a consequence, emission can occur even if the explicitly resolved wind speed is less than the threshold, as long as the subgrid scale variability is large enough. In the AGCM, subgrid wind fluctuations are dominated by dry convection. This favors dust emission over deserts, where there is continuous mixing within the boundary layer due to intense solar heating of the surface. Particles emitted over arid regions are farther from precipitation and mixed higher above the surface by dry convection. This increases their wet and dry deposition lifetimes, respectively, increasing the aerosol load for a given emission. The AGCM's identification of "preferred meteorology'' for emission by subgrid circulations complements the preferred sources of erodible particles included in other models. Given the introduction of subgrid variability, the AGCM's dust aerosol burden improves significantly, compared to the Total Ozone Mapping Spectrometer ( TOMS) and advanced very high resolution radiometer (AVHRR) aerosol optical thickness (AOT) retrievals, over the Sahara, Sahel, and the Taklimakan as well as downwind of these regions, considered to be major sources of dust emission. This mechanistic representation of subgrid variability allows us to calculate the atmospheric burden of dust under different climates, where emission can change due to altered boundary layer variability in addition to changes in the mean wind speed. C1 Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10027 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21250 USA. RP Columbia Univ, Dept Appl Phys & Appl Math, 200 SW Mudd Bldg,500 W 120th St, New York, NY 10027 USA. EM rcakmur@giss.nasa.gov; rmiller@giss.nasa.gov; torres@tparty.gsfc.nasa.gov RI Miller, Ron/E-1902-2012; Torres, Omar/G-4929-2013 NR 103 TC 79 Z9 80 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 1 PY 2004 VL 109 IS D7 AR D07201 DI 10.1029/2003JD004067 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 811AJ UT WOS:000220744500001 ER PT J AU Zhang, H Mudawar, I Hasan, MM AF Zhang, H Mudawar, I Hasan, MM TI A method for assessing the importance of body force on flow boiling CHF SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE boiling; channel flow; heat transfer; microgravity; phase change ID CRITICAL HEAT-FLUX; VERTICAL SURFACES; MECHANISM; MODEL; WALL AB Experiments were performed to examine the effects of body force on flow boiling CHF. FC-72 was boiled along one wall of a transparent rectangular flow channel that permitted photographic study of the vapor-liquid interface just prior to CHF. High-speed video imaging techniques were used to identify dominant CHF mechanisms corresponding to different flow orientations and liquid velocities. Six different CHF regimes were identified: Wavy Vapor Layer; Pool Boiling, Stratification, Vapor Counterflow, Vapor Stagnation, and Separated Concurrent Vapor Flow. CHF showed significant sensitivity to orientation for flow velocities below 0.2 m/s, where extremely low CHF values where measured, especially with downward-facing heated wall and downflow orientations. High flow velocities dampened the effects of orientation considerably. The CHF data were used to assess the suitability of previous CHF models and correlations. It is shown the Interfacial Lift-off Model is very effective at predicting CHF far high velocities at all orientations. The flooding limit, on the other hand, is useful at estimating CHF at low velocities and for downflow orientations. A new method consisting of three dimensionless criteria is developed to determine the minimum flow velocity required to overcome body force effects on near-saturated flow boiling CHF. C1 Purdue Univ, Boiling & Two Phase Flow Lab, Sch Mech Engn, W Lafayette, IN 47907 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Zhang, H (reprint author), Purdue Univ, Boiling & Two Phase Flow Lab, Sch Mech Engn, W Lafayette, IN 47907 USA. EM mudawar@ecn.purdue.edu NR 14 TC 24 Z9 24 U1 0 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD APR PY 2004 VL 126 IS 2 BP 161 EP 168 DI 10.1115/1.1651532 PG 8 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 816SV UT WOS:000221130500003 ER PT J AU Scott, CD Arepalli, S AF Scott, CD Arepalli, S TI A special issue selected refereed articles from NASA/rice university workshop on SWNT growth mechanisms SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Editorial Material C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Scott, CD (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RI Arepalli, Sivaram/A-5372-2010 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SCIENTIFIC PUBLISHERS PI STEVENSON RANCH PA 25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA SN 1533-4880 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD APR PY 2004 VL 4 IS 4 BP 305 EP 306 DI 10.1166/jnn.2004.055 PG 2 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 830KR UT WOS:000222121400001 ER PT J AU Nikolaev, P AF Nikolaev, P TI Gas-phase production of single-walled carbon nanotubes from carbon monoxide: A review of the HiPco process SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article; Proceedings Paper CT Workshop on Growth Mechanisms of Single-Wall Carbon Nanotubes CY FEB 28-MAR 02, 2003 CL Boerne, TX DE carbon nanotubes; chemical vapor deposition; carbon monoxide ID CATALYTIC GROWTH; VAPOR-PHASE; LARGE-SCALE; HYDROCARBONS; DISPROPORTIONATION; DECOMPOSITION; PYROLYSIS; REACTOR; FIBERS; IRON AB The latest process for producing large quantities of single-walled carbon nanotubes (SWNTs) to emerge from the Rice University, dubbed HiPco, is living up to its promise. The current production rates approach 450 mg/h (or 10 g/day), and nanotubes typically have no more than 7 mol % of iron impurities. Second-gene ration HiPco apparatus can run continuously for 7-10 days at a time. In the HiPco process nanotubes grow in high-pressure, high-temperature flowing CO on catalytic clusters of iron. Catalyst is formed in situ by thermal decomposition of iron pentacarbonyl, which is delivered intact within a cold CO flow and then rapidly mixed with hot CO in the reaction zone. Upon heating, the Fe(CO)(5) decomposes into atoms that condense into larger clusters. SWNTs nucleate and grow on these particles in the gas phase via CO disproportionation: CO + CO --> CO2 + C (SWNT), catalyzed by the Fe surface. The concentration of CO2 produced in this reaction is equal to that of carbon and can therefore serve as a useful real-time feedback parameter. It was used to study and optimize SWNT production as a function of temperature, pressure, and Fe(CO)(5) concentration. The results of the parametric study are in agreement with current understanding of the nanotube formation mechanism. C1 NASA, Lyndon B Johnson Space Ctr, GB Tech, Houston, TX 77058 USA. RP NASA, Lyndon B Johnson Space Ctr, GB Tech, Houston, TX 77058 USA. RI Nikolaev, Pavel/B-9960-2009 NR 22 TC 48 Z9 48 U1 3 U2 42 PU AMER SCIENTIFIC PUBLISHERS PI VALENCIA PA 26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USA SN 1533-4880 EI 1533-4899 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD APR PY 2004 VL 4 IS 4 BP 307 EP 316 DI 10.1166/jnn.2004.066 PG 10 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 830KR UT WOS:000222121400002 PM 15296221 ER PT J AU Arepalli, S AF Arepalli, S TI Laser ablation process for single-walled carbon nanotube production SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article; Proceedings Paper CT Workshop on Growth Mechanisms of Single-Wall Carbon Nanotubes CY FEB 28-MAR 02, 2003 CL Boerne, TX DE laser ablation; single-walled carbon nanotube (SWNT); SWNT production; flow tubes ID LARGE-SCALE PRODUCTION; CATALYTIC GROWTH; VAPORIZATION; TEMPERATURE; PLUME; CO2-LASER; DYNAMICS; YIELD; C-60; GAS AB Different types of lasers are now routinely used to prepare single-walled carbon nanotubes. The original method developed by researchers at Rice University used a "double-pulse laser oven" process. Several researchers have used variations of the lasers to include one-laser pulse (green or infrared), different pulse widths (ns to mus as well as continuous wave), and different laser wavelengths (e.g., CO2, or free electron lasers in the near to far infrared). Some of these variations are tried with different combinations and concentrations of metal catalysts, buffer gases (e.g., helium), oven temperatures, flow conditions, and even different porosities of the graphite targets. This article is an attempt to cover all these variations and their relative merits. Possible growth mechanisms under these different conditions will also be discussed. C1 NASA, Lyndon B Johnson Space Ctr, GB Tech, Houston, TX 77058 USA. RP Arepalli, S (reprint author), NASA, Lyndon B Johnson Space Ctr, GB Tech, 2101 NASA Rd 1, Houston, TX 77058 USA. RI Arepalli, Sivaram/A-5372-2010 NR 44 TC 44 Z9 44 U1 1 U2 13 PU AMER SCIENTIFIC PUBLISHERS PI STEVENSON RANCH PA 25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA SN 1533-4880 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD APR PY 2004 VL 4 IS 4 BP 317 EP 325 DI 10.1166/jnn.2004.072 PG 9 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 830KR UT WOS:000222121400003 PM 15296222 ER PT J AU Scott, CD AF Scott, CD TI Chemical models for simulating single-walled nanotube production in arc vaporization and laser ablation processes SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article; Proceedings Paper CT Workshop on Growth Mechanisms of Single-Wall Carbon Nanotubes CY FEB 28-MAR 02, 2003 CL Boerne, TX DE carbon nanotubes; chemical kinetics; modeling; laser ablation; fullerenes; arcs ID PRESSURE CARBON-MONOXIDE; HIPCO PROCESS; REACTOR; GROWTH; MECHANISM; KINETICS; C-60; C-70 AB Chemical kinetic models for the nucleation and growth of clusters and single-walled carbon nanotube (SWNT) growth are developed for numerical simulations of the production of SWNTs. Two models that involve evaporation and condensation of carbon and metal catalysts, a full model involving all carbon clusters up to C-80, and a reduced model are discussed. The full model is based on a fullerene model, but nickel and carbon/nickel cluster reactions are added to form SWNTs from soot and fullerenes. The full model has a large number of species-so large that to incorporate them into a flow field computation for simulating laser ablation and arc processes requires that they be simplified. The model is reduced by defining large clusters that represent many various sized clusters. Comparisons are given between these models for cases that may be applicable to arc and laser ablation production. Solutions to the system of chemical rate Equations of these models for a ramped temperature profile show that production of various species, including SWNTs, agree to within about 50% for a fast ramp, and within 10% for a slower temperature decay time. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Scott, CD (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 21 TC 12 Z9 12 U1 1 U2 2 PU AMER SCIENTIFIC PUBLISHERS PI STEVENSON RANCH PA 25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA SN 1533-4880 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD APR PY 2004 VL 4 IS 4 BP 368 EP 376 DI 10.1166/jnn.2004.061 PG 9 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 830KR UT WOS:000222121400007 PM 15296226 ER PT J AU Farhat, S Hinkov, L Scott, CD AF Farhat, S Hinkov, L Scott, CD TI Arc process parameters for single-walled carbon nanotube growth and production: experiments and modeling SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article; Proceedings Paper CT Workshop on Growth Mechanisms of Single-Wall Carbon Nanotubes CY FEB 28-MAR 02, 2003 CL Boerne, TX DE carbon; nanotubes; growth; modeling; kinetics ID LARGE-SCALE PRODUCTION; DIAMETER DISTRIBUTION; CATALYTIC GROWTH; ELECTRIC-ARC; REACTOR; HYDROCARBONS; PHASE; SPECTROSCOPY; PYROLYSIS; C-60 AB Collarets rich in single-walled carbon nanotubes (SWCNTs) have been grown using a direct current arc method. Arc process parameters such as current, pressure, and anode to cathode distance were varied experimentally and by modeling to provide an optimal working window. The best collaret yields were obtained when helium was used as a buffer gas. Mixing helium with argon in the buffer permits controlling nanotube diameters. In addition to an experimental study, a modeling approach was developed assuming local thermal equilibrium and homogenous and heterogeneous neutral chemistry. The gas-phase chemical model involves 81 neutral carbon species (C-1, C-2, . . . , C-79, C-60F, C-70F) and 554 reactions with rates taken from data of Krestinin and Moravsky. Axial profiles of temperature, C atom, C-2 radical, and fullerene distributions in the reactor are predicted as a function of process parameters. Carbon nanotube growth is considered by a set of surface reactions simulating open nanotube growth. Because nanotube surface chemistry is controlled by the local terminated bond and not by the bulk nanotube bond, a mechanistic approach based on the formal resemblance between the bonding and the structure of open nanotube and other carbon surfaces is proposed to explain nanotube growth. Predicted growth rates are in the range of 100 to 1000 mum/min. C1 Univ Paris 13, LIMHP, F-93430 Villetaneuse, France. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Univ Paris 13, LIMHP, Ave JB Clement, F-93430 Villetaneuse, France. NR 50 TC 16 Z9 16 U1 1 U2 6 PU AMER SCIENTIFIC PUBLISHERS PI VALENCIA PA 26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USA SN 1533-4880 EI 1533-4899 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD APR PY 2004 VL 4 IS 4 BP 377 EP 389 DI 10.1166/jnn.2004.057 PG 13 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 830KR UT WOS:000222121400008 PM 15296227 ER PT J AU Greendyke, RB Swain, JA Scott, CD AF Greendyke, RB Swain, JA Scott, CD TI Computational fluid dynamics simulation of laser-ablated carbon plume propagation in varying background gases for single-walled nanotube synthesis SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article; Proceedings Paper CT Workshop on Growth Mechanisms of Single-Wall Carbon Nanotubes CY FEB 28-MAR 02, 2003 CL Boerne, TX DE single-walled carbon nanotubes; computational approach; synthesis AB A computational fluid dynamics study was conducted to model the plume resulting from the laser ablation of a carbon target in a laser ablation oven for the production of carbon single-walled nanotubes (SWNTs). The goal is to gain understanding into the fluid dynamics and thermodynamics of the plume to ultimately improve SWNT production techniques. The simulations were carried out with a 12-species, 14-reaction chemistry model that included carbon species from C to C-6. Metal catalysts in the carbon target were ignored for these simulations. Simulation times ranged from immediate ablation onset to 8 ms past the initial onset of ablation. A secondary goal of the study was to compare computational results with experimental results for three different background gases in the laser ablation oven-argon, helium, and nitrogen. Computational results indicated that lighter carbon species were more quickly diffused into the background gas for helium and nitrogen, resulting in lower localized mass fractions of carbon nanotube "feedstock." The expectation is that this effect will reduce the production of carbon nanotubes, which has been confirmed by experimental evidence. From this investigation, a possible "indicator species" for the production of SWNT appears to be C-5. C1 Univ Texas, Dept Mech Engn, Tyler, TX USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Greendyke, RB (reprint author), Univ Texas, Dept Mech Engn, Tyler, TX USA. NR 11 TC 4 Z9 4 U1 0 U2 1 PU AMER SCIENTIFIC PUBLISHERS PI STEVENSON RANCH PA 25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA SN 1533-4880 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD APR PY 2004 VL 4 IS 4 BP 441 EP 449 DI 10.1166/jnn.2004.058 PG 9 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 830KR UT WOS:000222121400016 PM 15296235 ER PT J AU Pan, JY Yan, XH Jo, YH Zheng, QN Liu, WT AF Pan, JY Yan, XH Jo, YH Zheng, QN Liu, WT TI A new method for estimation of the sensible heat flux under unstable conditions using satellite vector winds SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID ATMOSPHERIC CONVERGENCE ZONES; THERMOHALINE CIRCULATION; PARAMETERIZATIONS; SCATTEROMETER; VARIABILITY; TEMPERATURE; MODEL; OCEAN AB It has been difficult to estimate the sensible heat flux at the air - sea interface using satellite data because of the difficulty in remotely observing the sea level air temperature. In this study, a new method is developed for estimating the sensible heat flux using satellite observations under unstable conditions. The basic idea of the method is that the air - sea temperature difference is related to the atmospheric convergence. Employed data include the wind convergence, sea level humidity, and sea surface temperature. These parameters can be derived from the satellite wind vectors, Special Sensor Microwave Imager (SSM/I) precipitable water, and Advanced Very High Resolution Radiometer (AVHRR) observations, respectively. The authors selected a region east of Japan as the test area where the atmospheric convergence appears all year. Comparison between the heat fluxes derived from the satellite data and from the National Centers for Environmental Prediction (NCEP) data suggests that the rms difference between the two kinds of sensible heat fluxes has low values in the sea area east of Japan with a minimum of 10.0 W m(-2). The time series of the two kinds of sensible heat fluxes at 10 locations in the area are in agreement, with rms difference ranging between 10.0 and 14.1 W m(-2) and correlation coefficient being higher than 0.7. In addition, the National Aeronautics and Space Administration ( NASA) Goddard Satellite-Based Surface Turbulent Flux (GSSTF) was used for a further comparison. The low-rms region with high correlation coefficient (>0.7) was also found in the region east of Japan with a minimum of 12.2 W m(-2). Considering the nonlinearity in calculation of the sensible monthly means, the authors believe that the comparison with GSSTF is consistent with that with NCEP data. C1 Univ Delaware, Grad Coll Marine Studies, Newark, DE USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Pan, JY (reprint author), Univ So Mississippi, Dept Marine Sci, 1020 Balch Blvd, Stennis Space Ctr, MS 39529 USA. EM jiayi.pan@usm.edu RI Zheng, Quanan/F-9025-2010 NR 16 TC 3 Z9 3 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD APR PY 2004 VL 34 IS 4 BP 968 EP 977 DI 10.1175/1520-0485(2004)034<0968:ANMFEO>2.0.CO;2 PG 10 WC Oceanography SC Oceanography GA 815VP UT WOS:000221070100018 ER PT J AU Sjogreen, B Yee, HC AF Sjogreen, B Yee, HC TI Multiresolution wavelet based adaptive numerical dissipation control for high order methods SO JOURNAL OF SCIENTIFIC COMPUTING LA English DT Article DE low dissipation; high order finite difference method; shock waves; multi resolution; wavelets; TVD schemes ID HYPERBOLIC CONSERVATION-LAWS; EULER EQUATIONS; SCHEMES; TRANSFORMS AB The recently developed essentially fourth-order or higher low dissipative shock-capturing scheme of Yee, Sandham, and Djomehri [25] aimed at minimizing numerical dissipations for high speed compressible viscous flows containing shocks, shears and turbulence. To detect non-smooth behavior and control the amount of numerical dissipation to be added, Yee et al. employed an artificial compression method (ACM) of Harten [4] but utilize it in an entirely different context than Harten originally intended. The ACM sensor consists of two tuning parameters and is highly physical problem dependent. To minimize the tuning of parameters and physical problem dependence, new sensors with improved detection properties are proposed. The new sensors are derived from utilizing appropriate non-orthogonal wavelet basis functions and they can be used to completely switch off the extra numerical dissipation outside shock layers. The non-dissipative spatial base scheme of arbitrarily high order of accuracy can be maintained without compromising its stability at all parts of the domain where the solution is smooth. Two types of redundant non-orthogonal wavelet basis functions are considered. One is the B-spline wavelet ( Mallat and Zhong [14]) used by Gerritsen and Olsson [3] in an adaptive mesh refinement method, to determine regions where refinement should be done. The other is the modification of the multiresolution method of Harten [ 5] by converting it to a new, redundant, non-orthogonal wavelet. The wavelet sensor is then obtained by computing the estimated Lipschitz exponent of a chosen physical quantity ( or vector) to be sensed on a chosen wavelet basis function. Both wavelet sensors can be viewed as dual purpose adaptive methods leading to dynamic numerical dissipation control and improved grid adaptation indicators. Consequently, they are useful not only for shock-turbulence computations but also for computational aeroacoustics and numerical combustion. In addition, these sensors are scheme independent and can be stand-alone options for numerical algorithms other than the Yee et al. scheme. C1 KTH, Dept Numer Anal & Comp Sci, S-10044 Stockholm, Sweden. NASA, Ames Res Ctr, RIACS, Moffett Field, CA 94035 USA. RP KTH, Dept Numer Anal & Comp Sci, S-10044 Stockholm, Sweden. EM bjorns@nada.kth.se NR 29 TC 52 Z9 53 U1 0 U2 9 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0885-7474 EI 1573-7691 J9 J SCI COMPUT JI J. Sci. Comput. PD APR PY 2004 VL 20 IS 2 BP 211 EP 255 DI 10.1023/B:JOMP.0000008721.30071.e4 PG 45 WC Mathematics, Applied SC Mathematics GA 754WH UT WOS:000187355200003 ER PT J AU Bertino, MF Hund, JF Zhang, G Sotiriou-Leventis, C Tokuhiro, AT Leventis, N AF Bertino, MF Hund, JF Zhang, G Sotiriou-Leventis, C Tokuhiro, AT Leventis, N TI Room temperature synthesis of noble metal clusters in the mesopores of mechanically strong silica-polymer aerogel composites SO JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY LA English DT Article DE aerogels; radiolysis ID BIMETALLIC CLUSTERS; PULSE-RADIOLYSIS; AQUEOUS-SOLUTION; INTERFACE; REDUCTION; ELECTRON; ACETONE AB Clusters of Ag and Au have been formed in the bulk of mechanically strong silica-polymer aerogel composite monoliths. For that purpose, base-catalyzed silica hydrogels were washed with a 50% w/w acetone/diisocyanate (di-ISO) solution, and cured at 55degreesC for 3 days. Unreacted di-ISO solution was washed off with acetone, and the gels were washed with a acetone solutions of Ag+ or AuCl4- (3 x 10(-4) mol.L-1), containing also 0.2 mol.L-1 of 2-propanol as radical scavenger. Metal clusters were formed upon radiolytic reduction (gamma rays, 48-72 h, 7-7.5 kGy) of the precursor ions. After irradiation, the hydrogels were washed with acetone, and dried in supercritical CO2. The resulting aerogel monoliths had a density of 0.56 g.cm(-3), a surface area of about 160 m(2).g(-1), and an average pore diameter of about 200 nm. Transmission electron microscopy showed that the metal clusters are free of contamination, with a cubic face centered structure, and a narrow size distribution, centered around 10 nm. The elastic module, measured with a three-point flexural bending method, was in the 60-70 MPa range, and the load at rupture between 16 and 19 kg. Thermogravimetric analysis showed that the composites were stable up to about 300degreesC. These results are in excellent agreement with results obtained previously for as-grown, di-ISO cross-linked silica aerogels, and show that addition of metal clusters and gamma irradiation to a dose corresponding to a permanence of several years in low earth orbit at high inclination did not affect the chemical identity, the mechanical strength, the porosity and the bulk density of the composite aerogel monoliths. C1 Univ Missouri, Dept Phys, Rolla, MO 65409 USA. Univ Missouri, Dept Chem, Rolla, MO 65409 USA. Univ Missouri, Dept Nucl Engn, Rolla, MO 65409 USA. NASA, Glenn Res Ctr, Div Mat, Polymers Branch, Cleveland, OH 44135 USA. RP Bertino, MF (reprint author), Univ Missouri, Dept Phys, Rolla, MO 65409 USA. EM massimo@umr.edu; Nicholas.leventis@nasa.gov NR 26 TC 28 Z9 29 U1 0 U2 24 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0928-0707 J9 J SOL-GEL SCI TECHN JI J. Sol-Gel Sci. Technol. PD APR PY 2004 VL 30 IS 1 BP 43 EP 48 DI 10.1023/B:JSST.0000028178.25991.9e PG 6 WC Materials Science, Ceramics SC Materials Science GA 821RK UT WOS:000221480000005 ER PT J AU Dempsey, PJ Afjeh, AA AF Dempsey, PJ Afjeh, AA TI Integrating oil debris and vibration gear damage detection technologies using fuzzy logic SO JOURNAL OF THE AMERICAN HELICOPTER SOCIETY LA English DT Article; Proceedings Paper CT 58th Annual Forum of the American-Helicopter-Society CY JUN 11-13, 2002 CL MONTREAL, CANADA SP Amer Helicopter Soc AB A diagnostic tool for detecting damage to spur gears was developed. Two different measurement technologies, wear debris analysis and vibration, were integrated into a health monitoring system for detecting surface fatigue pitting damage on gears. This integrated system showed improved detection and decision-making capabilities as compared to using individual measurement technologies. This diagnostic tool was developed and evaluated experimentally by collecting vibration and oil debris data from fatigue tests performed in the NASA Glenn Spur Gear Fatigue Test Rig. Experimental data were collected during experiments performed in this test rig with and without pitting. Results show combining the two measurement technologies improves the detection of pitting damage on spur gears. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Univ Toledo, Toledo, OH 43606 USA. RP Dempsey, PJ (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 23 TC 8 Z9 8 U1 0 U2 1 PU AMER HELICOPTER SOC INC PI ALEXANDRIA PA 217 N WASHINGTON ST, ALEXANDRIA, VA 22314 USA SN 0002-8711 J9 J AM HELICOPTER SOC JI J. Am. Helicopter Soc. PD APR PY 2004 VL 49 IS 2 BP 109 EP 116 PG 8 WC Engineering, Aerospace SC Engineering GA 818HB UT WOS:000221235100002 ER PT J AU Jhemi, AA Carlson, EB Zhao, YYJ Chen, RTN AF Jhemi, AA Carlson, EB Zhao, YYJ Chen, RTN TI Optimization of rotorcraft flight following engine failure SO JOURNAL OF THE AMERICAN HELICOPTER SOCIETY LA English DT Article; Proceedings Paper CT 56th Annual Forum of the American-Helicopter-Society CY MAY 02-04, 2000 CL VIRGINIA BEACH, VA SP Amer Helicopter Soc ID TILTROTOR AIRCRAFT; OPTIMAL TAKEOFF; HELICOPTER; PREDICTION; OPERATION AB Dynamic optimization methods can be used to provide quick and low-cost iterations in rotorcraft analysis and design, and to generate benchmark results for flight tests. In this paper, key steps in the effective application of dynamic optimization methods are identified. Numerical solution algorithms are reviewed. The uses of dynamic optimization methods are illustrated with examples of flight path optimizations for both helicopter and tiltrotor aircraft following engine failure. In these examples, flights after an engine failure are formulated as dynamic optimization problems. Performance indices and constraints are properly selected so that conclusions can be drawn about rotorcraft performance boundaries following an engine failure. C1 Boeing Helicopters, Mesa, AZ USA. Bell Helicopter, Dallas, TX USA. Univ Minnesota, Minneapolis, MN USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Jhemi, AA (reprint author), Boeing Helicopters, Mesa, AZ USA. NR 27 TC 1 Z9 2 U1 0 U2 2 PU AMER HELICOPTER SOC INC PI ALEXANDRIA PA 217 N WASHINGTON ST, ALEXANDRIA, VA 22314 USA SN 0002-8711 J9 J AM HELICOPTER SOC JI J. Am. Helicopter Soc. PD APR PY 2004 VL 49 IS 2 BP 117 EP 126 PG 10 WC Engineering, Aerospace SC Engineering GA 818HB UT WOS:000221235100003 ER PT J AU Chao, DF Zhang, NL Yang, WJ AF Chao, DF Zhang, NL Yang, WJ TI Nucleate pool boiling on copper-graphite composite surfaces and its enhancement mechanism SO JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER LA English DT Article ID VAPOR BUBBLE; HEAT-TRANSFER; LIQUID; DEPARTURE AB An experimental study is performed on nucleate pool boiling in a highly wetting liquid, Freon-113, and a moderately wetting liquid, water, on copper-graphite (Cu-Gr) composite surfaces under atmospheric conditions. Boiling heat-flux data on the Cu-Gr surfaces are compared with those on a pure copper surface. Best-fit correlation equations are derived to relate the boiling heat flux to wall superheat and boiling heat-transfer coefficient with the heat flux for each liquid-solid combination. It is disclosed that the nucleate boiling heat transfer in both test liquids is augmented by the presence of graphite fibers and that the composite surface with 25% volume fraction of graphite fibers in the copper matrix exhibited the best enhancing performance in both test liquids. Water is characterized by a stronger enhancement and less degeneracy of the enhancement with an increase in the heat flux than Freon-113. The enhancement mechanism is proposed using a bubble departure model developed by the authors. C1 NASA, John H Glenn Res Ctr, Micrograv Sci Div, Cleveland, OH 44135 USA. Ohio Aerosp Inst, Cleveland, OH 44142 USA. Univ Michigan, Ann Arbor, MI 48109 USA. RP Chao, DF (reprint author), NASA, John H Glenn Res Ctr, Micrograv Sci Div, Mail Stop 77-5, Cleveland, OH 44135 USA. NR 26 TC 6 Z9 6 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0887-8722 J9 J THERMOPHYS HEAT TR JI J. Thermophys. Heat Transf. PD APR-JUN PY 2004 VL 18 IS 2 BP 236 EP 242 DI 10.2514/1.1103 PG 7 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 814FW UT WOS:000220961600010 ER PT J AU Prazenica, RJ Kurdila, AJ AF Prazenica, RJ Kurdila, AJ TI Volterra kernel identification using triangular wavelets SO JOURNAL OF VIBRATION AND CONTROL LA English DT Article DE nonlinear system identification; Volterra series; triangular wavelets; orthonormal wavelets; multiresolution analysis ID NONLINEAR-SYSTEMS; SERIES APPROACH; MEMORY AB The Volterra series provides a convenient framework for the representation of nonlinear dynamical systems. One of the main drawbacks of this approach, however, is the large number of terms that are often needed to represent Volterra kernels. In this paper we present an approach whereby wavelets are used to obtain low-order estimates of first-order and second-order Volterra kernels. Several constructions of tensor-product wavelets have been employed for some,Volterra kernel approximations. In this paper, a triangular wavelet basis is constructed for the representation of the triangular form of the second-order kernel. These wavelets are piecewise-constant, orthonormal, and are supported over the triangular domain over which the second-order kernel is defined. The well-known Haar wavelet is used concurrently for the identification of the first-order kernel. This kernel identification algorithm is demonstrated on a prototypical nonlinear oscillator. It is shown that accurate kernel estimates can be obtained in terms of a relatively small number of wavelet coefficients. It is also demonstrated that, for this particular system, the derived Volterra model is valid for input amplitudes below a specified bound. When the input amplitude exceeds this threshold, higher-order kernels are needed to adequately describe the system dynamics. Thus, the approach taken in this paper is applicable to a large class of nonlinear systems provided that the input excitation is sufficiently bounded. C1 NASA, Dryden Flight Res Ctr, Edwards AFB, CA 93523 USA. Univ Florida, Dept Mech & Aerosp Engn, Gainesville, FL 32611 USA. RP Prazenica, RJ (reprint author), NASA, Dryden Flight Res Ctr, POB 273,MS 4840D, Edwards AFB, CA 93523 USA. NR 28 TC 10 Z9 11 U1 0 U2 4 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 1077-5463 J9 J VIB CONTROL JI J. Vib. Control PD APR PY 2004 VL 10 IS 4 BP 597 EP 622 DI 10.1177/1077546304038269 PG 26 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 818VQ UT WOS:000221273000008 ER PT J AU Littnan, CL Baker, JD Parrish, FA Marshall, GJ AF Littnan, CL Baker, JD Parrish, FA Marshall, GJ TI Effects of video camera attachment on the foraging behavior of immature Hawaiian monk seals SO MARINE MAMMAL SCIENCE LA English DT Article ID SOUTHERN ELEPHANT SEALS; ANTARCTIC FUR SEALS; BODY-MASS LOSS; MONACHUS-SCHAUINSLANDI; MIROUNGA-LEONINA; CRITTERCAM; HABITAT; DEVICES C1 NOAA, Natl Marine Fisheries Serv, Pacific Isl Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI 96822 USA. Natl Geog Televis, Washington, DC 20036 USA. RP Littnan, CL (reprint author), NOAA, Natl Marine Fisheries Serv, Pacific Isl Fisheries Sci Ctr, Honolulu Lab, 2570 Dole St, Honolulu, HI 96822 USA. EM charles.littnan@noaa.gov NR 20 TC 15 Z9 16 U1 2 U2 14 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD APR PY 2004 VL 20 IS 2 BP 345 EP 352 DI 10.1111/j.1748-7692.2004.tb01164.x PG 8 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 811YJ UT WOS:000220806900015 ER PT J AU Ciesla, FJ Lauretta, DS Hood, LL AF Ciesla, FJ Lauretta, DS Hood, LL TI The frequency of compound chondrules and implications for chondrule formation SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID HEATING MODEL; COOLING RATES; SOLAR NEBULA; SIZE; CHONDRITES; PARTICLES AB The properties of compound chondrules and the implications that they have for the conditions and environment in which chondrules formed are investigated. Formulae to calculate the probability of detecting compound chondrules in thin sections are derived and applied to previous studies. This reinterpretation suggests that at least 5% of chondrules are compounds, a value that agrees well with studies in which whole chondrules were removed from meteorites. The observation that adhering compounds tend to have small contact arcs is strengthened by application of these formulae. While it has been observed that the secondaries of compound chondrules are usually smaller than their primaries, these same formulae suggest that this could be an observation bias. It is more likely than not that thin section analyses will identify compounds with secondaries that are smaller than their primaries. A new model for chondrule collisional evolution is also developed. From this model, it is inferred that chondrules would have formed, on average, in areas of the solar nebula that had solids concentrated at least 45 times over the canonical solar value. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. RP Ciesla, FJ (reprint author), NASA, Ames Res Ctr, MS 245-3, Moffett Field, CA 94035 USA. EM ciesla@cosmic.arc.nasa.gov NR 27 TC 25 Z9 25 U1 1 U2 1 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD APR PY 2004 VL 39 IS 4 BP 531 EP 544 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 815BF UT WOS:000221017100002 ER PT J AU Cloutis, EA Sunshine, JM Morris, RV AF Cloutis, EA Sunshine, JM Morris, RV TI Spectral reflectance-compositional properties of spinels and chromites: Implications for planetary remote sensing and geothermometry SO METEORITICS & PLANETARY SCIENCE LA English DT Review ID MANTLE OXYGEN FUGACITY; ORDINARY CHONDRITES; PETROGENETIC INDICATORS; CATION DISTRIBUTIONS; OPTICAL-ABSORPTION; ORTHO-PYROXENE; THERMODYNAMIC PROPERTIES; CARBONACEOUS CHONDRITES; SYSTEM MGO-AL2O3-SIO2; GARNET-PERIDOTITE AB Reflectance spectra of spinels and chromites have been studied as a function of composition. These two groups of minerals are spectrally distinct, which relates largely to differences in the types of major cations present. Both exhibit a number of absorption features in the 0.3-26 mum region that show systematic variations with composition and can be used to quantify or constrain certain compositional parameters, such as cation abundances, and site occupancies. For spinels, the best correlations exist between Fe2+ content and wavelength positions of the 0.46, 0.93, 2.8, Restrahelen, 12.3, 16.2, and 17.5 mum absorption features, At and Fe3+ content with the wavelength position of the 0.93 pm absorption feature, and Cr content from the depth of the absorption band near 0.55 mum. For chromites, the best correlations exist between Cr content and wavelength positions of the, 0.49, 0.59, 2, 17.5, and 23 mum absorption features, Fe2+ and Mg contents with the wavelength position of the 1.3 mum absorption feature, and Al content with the wavelength position of the 2 mum absorption feature. At shorter wavelengths, spinels and chromites are most readily distinguished by the wavelength position of the absorption band in the 2 mum region (<2.1 mum for spinels, >2.1 mum for chromite), while at longer wavelengths, spectral differences are more pronounced. The importance of being able to derive compositional information for spinels and chromites from spectral analysis stems from the relationship between composition and petrogenetic conditions (pressure, temperature, oxygen fugacity) and the widespread presence of spinels and chromites in the inner solar system. When coupled with the ability to derive compositional information for mafic silicates from spectral analysis, this opens up the possibility of deriving petrogenetic information for remote spinel- and chromite-bearing targets from analysis of their reflectance spectra. C1 Univ Winnipeg, Dept Geog, Winnipeg, MB R3B 2E9, Canada. Sci Applicat Int Corp, Chantilly, VA USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Univ Winnipeg, Dept Geog, Winnipeg, MB R3B 2E9, Canada. EM e.cloutis@uwinnipeg.ca NR 107 TC 61 Z9 62 U1 2 U2 3 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1086-9379 EI 1945-5100 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD APR PY 2004 VL 39 IS 4 BP 545 EP 565 PG 21 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 815BF UT WOS:000221017100003 ER PT J AU Bounoua, L DeFries, RS Imhoff, ML Steininger, MK AF Bounoua, L DeFries, RS Imhoff, ML Steininger, MK TI Land use and local climate: A case study near Santa Cruz, Bolivia SO METEOROLOGY AND ATMOSPHERIC PHYSICS LA English DT Article ID SURFACE PARAMETERIZATION SIB2; GENERAL-CIRCULATION MODEL; DOUBLED ATMOSPHERIC CO2; TERRESTRIAL CARBON METABOLISM; TROPICAL DEFORESTATION; MINIMUM TEMPERATURE; GLOBAL CLIMATE; COVER CHANGE; VEGETATION; SCALE AB The Tierras Bajas regions of eastern Santa Cruz, Bolivia have undergone among the most rapid rates of concentrated deforestation during the 1980s and 1990s. We investigate the sensitivity of local climate to these land cover changes as observed from Landsat images acquired between 1975 and 1999. The Simple Biosphere model (SiB2) is used to assess the effects of both morphological and physiological changes in vegetation and the implications for fluxes of water, energy and carbon between the vegetation and the atmosphere during the rainy season. Conversion from tropical forest to cropland implicates morphological changes in vegetation as the primary drivers for a daily maximum warming of about 2degreesC and a slight nighttime cooling, suggesting that clearing of tropical forests for agricultural use may increase the diurnal temperature range, mainly by increasing the maximum temperature. On the other hand, the conversion of wooded grassland to cropland resulted in a similar daily warming and drying but exclusively due to vegetation physiological activity. The area-averaged monthly mean response for each conversion type resulted in a warming of about 0.6degreesC for the conversion of broadleaf evergreen and 1.2degreesC for conversion of wooded grassland. These temperature differences represent an augmentation in the local heat source associated with a reduction in evapotranspiration due to land cover conversion and do not reflect variations forced by changes in atmospheric circulation. When averaged over the entire domain, the effect of landscape conversion results in a reduction of the latent heat flux and an increase in sensible heat flux, producing a large-scale apparent heat source of 0.5degreesC during January. This warming is in line with an increasing trend observed in monthly mean temperature in Santa Cruz, Bolivia during the same period. C1 NASA, Biospher Sci Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. Univ Maryland, Dept Geog, College Pk, MD 20742 USA. RP Bounoua, L (reprint author), NASA, Biospher Sci Branch, Goddard Space Flight Ctr, Code 923, Greenbelt, MD 20771 USA. EM bounoua@dounia.gsfc.nasa.gov RI Garcia Bustamante, Elena/H-4188-2012 OI Garcia Bustamante, Elena/0000-0002-2677-0252 NR 40 TC 15 Z9 15 U1 1 U2 9 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0177-7971 J9 METEOROL ATMOS PHYS JI Meteorol. Atmos. Phys. PD APR PY 2004 VL 86 IS 1-2 BP 73 EP 85 DI 10.1007/s00703-003-0616-8 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 816NH UT WOS:000221116100006 ER PT J AU Dufrene, B Blalock, B Cristoloveanu, S Akarvardar, K Higashino, T Mojarradi, M AF Dufrene, B Blalock, B Cristoloveanu, S Akarvardar, K Higashino, T Mojarradi, M TI Subthreshold slope modulation in G(4)-FET transistors SO MICROELECTRONIC ENGINEERING LA English DT Article; Proceedings Paper CT 13th Biennial Conference on Insulating Films on Semiconductors CY JUN 18-20, 2003 CL Barcelona, SPAIN DE G(4)-FET; multiple gates; subthreshold slope AB We describe the operation of the novel Sol four-gate transistor (G(4)-FET) in the subthreshold region. The subthreshold slope, which may be defined with respect to either the junction gates or MOS gates, is adjustable using the remaining gates. A comparison of conventional MOSFET swings and G(4)-FET swings shows improved subthreshold slope. Systematic experimental data and simulations show the bias conditions for optimized performance. (C) 2004 Elsevier B.V. All rights reserved. C1 Univ Tennessee, Dept Elect & Comp Engn, Knoxville, TN 37996 USA. ENSERG, UJF, INPG,UMR CNRS, Inst Microelect Electromagnetism & Photon, Grenoble, France. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Dufrene, B (reprint author), Univ Tennessee, Dept Elect & Comp Engn, Knoxville, TN 37996 USA. EM dufrene@ieee.org NR 3 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9317 J9 MICROELECTRON ENG JI Microelectron. Eng. PD APR PY 2004 VL 72 IS 1-4 BP 347 EP 351 DI 10.1016/j.mee.2004.01.029 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Optics; Physics, Applied SC Engineering; Science & Technology - Other Topics; Optics; Physics GA 815BJ UT WOS:000221017500063 ER PT J AU Jaffe, RL Gonnet, P Werder, T Walther, JH Koumoutsakos, P AF Jaffe, RL Gonnet, P Werder, T Walther, JH Koumoutsakos, P TI Water-carbon interactions - 2: Calibration of potentials using contact angle data for different interaction models SO MOLECULAR SIMULATION LA English DT Article; Proceedings Paper CT Nanotech 2003 Conference CY 2003 CL SAN FRANCISCO, CALIFORNIA DE graphite; molecular dynamics; contact angle; water-graphite interface; water-carbon potential functions ID HYDROGEN-BOND; LIQUID WATER; NANOTUBES; GRAPHITE; SIMULATIONS; STRENGTH AB Molecular dynamics simulations of water droplets on graphite are carried out to determine the contact angle for different water-carbon potential functions. Following the procedure of Werder et al. [ J. Phys. Chem. B , 107 (2003) 1345], the C-O Lennard-Jones well depth is varied to recover the experimental value for the contact angle (84-86degrees) using a 2000-molecule water droplet and compensating for the line tension effect that lowers the contact angle for increasing droplet size. For the discrete graphite surface model studied by Werder et al. , the effects of adding C-H Lennard-Jones interactions and changing the long-range cut-off distance are considered. In addition, a continuum graphite surface model is studied for which the water-graphite interaction energy depends only on the normal distance ( z ) from the water oxygen to the surface. This new model, with z(-10) repulsion and z(-4) attraction, is formulated in terms of the standard Lennard-Jones parameters, for which the recommended values are sigma(CO) =3.19 Angstrom and epsilon(CO) =0.3651 kJ/mol. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. ETH, Inst Computat Sci, CH-8092 Zurich, Switzerland. RP Jaffe, RL (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM rjaffe@mail.arc.nasa.gov RI Gonnet, Pedro/A-6935-2008; Koumoutsakos, Petros/A-2846-2008; Walther, Jens/D-9549-2015 OI Gonnet, Pedro/0000-0003-4509-7291; Koumoutsakos, Petros/0000-0001-8337-2122; Walther, Jens/0000-0001-8100-9178 NR 29 TC 46 Z9 46 U1 1 U2 31 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0892-7022 J9 MOL SIMULAT JI Mol. Simul. PD APR PY 2004 VL 30 IS 4 BP 205 EP 216 DI 10.1080/08927020310001659124 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 775DY UT WOS:000189026500004 ER PT J AU Farrah, D Geach, J Fox, M Serjeant, S Oliver, S Verma, A Kaviani, A Rowan-Robinson, M AF Farrah, D Geach, J Fox, M Serjeant, S Oliver, S Verma, A Kaviani, A Rowan-Robinson, M TI The environments of hyperluminous infrared galaxies at 0.44 < z < 1.55 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : clusters : general; galaxies : evolution; galaxies : starburst; galaxies :; active; infrared : galaxies ID RADIO-QUIET QUASARS; ACTIVE GALACTIC NUCLEI; HOST GALAXIES; CLUSTER ENVIRONMENTS; LUMINOSITY FUNCTION; HIDDEN QUASAR; IRAS GALAXIES; LOUD QUASARS; RICH CLUSTER; EVOLUTION AB We present deep wide-field K-s-band observations of six Hyperluminous Infrared Galaxies (HLIRGs) spanning a redshift range 0.44=190+/-45 Mpc(1.77). The range in environments, and the mean clustering level, are both greater than those seen in local IR-luminous galaxies, from which we infer that the range of galaxy evolution processes driving IR-luminous galaxy evolution at z>0.5 is greater than locally, and includes mergers between gas-rich spiral galaxies in the field, but also includes encounters in clusters and hierarchical build-up. The similarity in the range of environments and mean clustering amplitude between our sample and QSOs over a similar redshift range is consistent with the interpretation where evolutionary connections between IR-luminous galaxies and QSOs are stronger at z>0.5 than locally, and that, at these redshifts, the processes that drive QSO evolution are similar to those that drive IR-luminous galaxy evolution. From comparison of the HLIRG and QSO host galaxies we further postulate that a larger fraction of IR-luminous galaxies pass through an optical QSO stage at z>0.5 than locally. C1 CALTECH, Jet Prop Lab, SIRTF Sci Ctr, Pasadena, CA 91125 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Astrophys Grp, London SW7 2BW, England. Univ London Queen Mary Coll, Astron Unit, London E1 4NS, England. Univ Kent, Sch Phys Sci, Ctr Astrophys & Planetary Sci, Canterbury CT2 7NR, Kent, England. Univ Sussex, Ctr Astron, Brighton BN1 9QJ, E Sussex, England. Max Planck Inst Extraterr Phys, D-85741 Garching, Germany. RP Farrah, D (reprint author), CALTECH, Jet Prop Lab, SIRTF Sci Ctr, 4800 Oak Grove Dr, Pasadena, CA 91125 USA. EM duncan@ipac.caltech.edu NR 61 TC 17 Z9 17 U1 0 U2 0 PU BLACKWELL PUBLISHING LTD PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 1 PY 2004 VL 349 IS 2 BP 518 EP 526 DI 10.1111/j.1365-2966.2004.07515.x PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 810HE UT WOS:000220694600012 ER PT J AU Nguyen, P Ng, HT Yamada, T Smith, MK Li, J Han, J Meyyappan, M AF Nguyen, P Ng, HT Yamada, T Smith, MK Li, J Han, J Meyyappan, M TI Direct integration of metal oxide nanowire in vertical field-effect transistor SO NANO LETTERS LA English DT Article ID CRYSTALLINE IN2O3 NANOWIRES; INDIUM OXIDE; ELECTRONIC-PROPERTIES; GROWTH; FABRICATION; ARRAYS AB We demonstrate seamless direct integration of a semiconductor nanowire grown using a bottom-up approach to obtain a vertical field-effect transistor (VFET), We first synthesize single crystalline semiconductor indium oxide (In2O3) nanowires projecting vertically and uniformly on a nonconducting optical sapphire substrate. Direct electrical contact to the nanowires is uniquely provided by a self-assembled underlying ln(2)O(3) buffer layer formed in-situ during the nanowire growth. A controlled time-resolved growth study reveals dynamic simultaneous nucleation and epitaxial growth events, driven by two competitive growth mechanisms. Based on the nanowire-integrated platform, a depletion mode n-channel VFET with an In2O3 nanowire constituting the active channel is fabricated. Our unique vertical device architecture could potentially lead to tera-level ultrahigh-density nanoscale electronic, and optoelectronic devices. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Ng, HT (reprint author), Eloret Corp, Sunnyvale, CA 94087 USA. EM hng@mail.arc.nasa.gov RI Yamada, Toshishige/E-7834-2012; Li, Jun/H-7771-2013 OI Yamada, Toshishige/0000-0001-7145-9212; Li, Jun/0000-0002-3689-8946 NR 22 TC 232 Z9 234 U1 7 U2 43 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD APR PY 2004 VL 4 IS 4 BP 651 EP 657 DI 10.1021/nl0498536 PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 812RY UT WOS:000220857800024 ER PT J AU Wade, LA Shapiro, IR Ma, ZY Quake, SR Collier, CP AF Wade, LA Shapiro, IR Ma, ZY Quake, SR Collier, CP TI Correlating AFM probe morphology to image resolution for single-wall carbon nanotube tips SO NANO LETTERS LA English DT Article ID ATOMIC-FORCE MICROSCOPE; DIRECT GROWTH AB Scanning and transmission electron microscopy were used to image hundreds of single-wall carbon nanotube probes and to correlate probe morphology with AFM image resolution. Several methods for fabricating such probes were evaluated, resulting in a procedure that produces image-quality single-wall nanotube probes at a rate compatible with their routine use. Surprisingly, about one-third of the tips image with resolution better than the nanotube probe diameter and, in exceptional cases, with resolution better than 1 nm. This represents the highest lateral resolution reported to date for a SWNT probe. C1 CALTECH, Dept Chem, Pasadena, CA 91125 USA. CALTECH, Dept Appl Phys, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Collier, CP (reprint author), CALTECH, Dept Chem, Pasadena, CA 91125 USA. EM collier@caltech.edu NR 22 TC 59 Z9 61 U1 0 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD APR PY 2004 VL 4 IS 4 BP 725 EP 731 DI 10.1021/nl049976q PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 812RY UT WOS:000220857800037 ER PT J AU Krennrich, F Bond, IH Boyle, PJ Bradbury, SM Buckley, JH Carter-Lewis, D Celik, O Cui, W Daniel, M D'Vali, M Perez, IDC Duke, C Falcone, A Fegan, DJ Fegan, SJ Finley, JP Fortson, LF Gaidos, J Gammell, S Gibbs, K Gillanders, GH Grube, J Hall, J Hall, TA Hanna, D Hillas, AM Holder, J Horan, D Jarvis, A Kenny, GE Kertzman, M Kieda, D Kildea, J Knapp, J Kosack, K Krawczynski, H Lang, MJ LeBohec, S Linton, E Lloyd-Evans, J Milovanovic, A Moriarty, P Muller, D Nagai, T Nolan, S Ong, RA Pallassini, R Petry, D Power-Mooney, B Quinn, J Quinn, M Ragan, K Rebillot, P Reynolds, PT Rose, HJ Schroedter, M Sembroski, G Swordy, SP Syson, A Vassiliev, VV Walker, G Wakely, SP Weekes, TC Zweerink, J AF Krennrich, F Bond, IH Boyle, PJ Bradbury, SM Buckley, JH Carter-Lewis, D Celik, O Cui, W Daniel, M D'Vali, M Perez, IDC Duke, C Falcone, A Fegan, DJ Fegan, SJ Finley, JP Fortson, LF Gaidos, J Gammell, S Gibbs, K Gillanders, GH Grube, J Hall, J Hall, TA Hanna, D Hillas, AM Holder, J Horan, D Jarvis, A Kenny, GE Kertzman, M Kieda, D Kildea, J Knapp, J Kosack, K Krawczynski, H Lang, MJ LeBohec, S Linton, E Lloyd-Evans, J Milovanovic, A Moriarty, P Muller, D Nagai, T Nolan, S Ong, RA Pallassini, R Petry, D Power-Mooney, B Quinn, J Quinn, M Ragan, K Rebillot, P Reynolds, PT Rose, HJ Schroedter, M Sembroski, G Swordy, SP Syson, A Vassiliev, VV Walker, G Wakely, SP Weekes, TC Zweerink, J TI VERITAS: the Very Energetic Radiation Imaging Telescope Array System SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT 2nd VERITAS Symposium on TeV Astrophysics from Extragalactic Sources CY APR 24-26, 2003 CL Adler Planetarium & AStron Museum, Chicago, IL HO Adler Planetarium & AStron Museum DE gamma-ray astronomy; TeV energies; atmospheric Cherenkov detectors AB The Very Energetic Radiation Imaging Telescope Array System (VERITAS) is the major next generation imaging atmospheric Cherenkov gamma-ray telescope in the western hemisphere and will be located in southern Arizona nearby Kitt Peak National Observatory. The VERITAS observatory will provide unprecedented sensitivity to photon energies between 50 GeV and 50 TeV. The first stage is an array of four telescopes to be fully operational in early 2006, with an expansion to seven telescopes envisioned for 2008. The construction of a prototype telescope is underway, for which first light is expected in Fall 2003. The technical concept is outlined and a progress report is given. (C) 2004 Published by Elsevier B.V. C1 Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Univ Leeds, Leeds LS2 9JT, W Yorkshire, England. Univ Chicago, Chicago, IL 60637 USA. Washington Univ, St Louis, MO 63130 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Purdue Univ, W Lafayette, IN 47907 USA. Grinnell Coll, Grinnell, IA 50112 USA. Natl Univ Ireland Univ Coll Dublin, Dublin 4, Ireland. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Natl Univ Ireland Univ Coll Galway, Galway, Ireland. Univ Utah, Salt Lake City, UT 84112 USA. Univ Arkansas, Little Rock, AR 72204 USA. McGill Univ, Montreal, PQ H3A 2T5, Canada. Depauw Univ, Greencastle, IN 46135 USA. Galway Mayo Inst Technol, Galway, Ireland. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. NASA, GSFC, Greenbelt, MD 20771 USA. Cork Inst Technol, Cork, AR, Ireland. RP Krennrich, F (reprint author), Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. EM krennich@iastate.edu RI Daniel, Michael/A-2903-2010; OI Daniel, Michael/0000-0002-8053-7910; Cui, Wei/0000-0002-6324-5772; Knapp, Johannes/0000-0003-1519-1383; Lang, Mark/0000-0003-4641-4201 NR 7 TC 12 Z9 12 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD APR PY 2004 VL 48 IS 5-6 BP 345 EP 349 DI 10.1016/j.newar.2003.12.050 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 815ZK UT WOS:000221080000005 ER PT J AU Georganopoulos, M Kazanas, D AF Georganopoulos, M Kazanas, D TI Decelerating flows in TeV blazars SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT 2nd VERITAS Symposium on TeV Astrophysics from Extragalactic Sources CY APR 24-26, 2003 CL Adler Planetarium & AStron Museum, Chicago, IL HO Adler Planetarium & AStron Museum DE galaxies : active; quasars : general-; radiation mechanisms : nonthermal; X-rays : galaxies ID HIGH-ENERGY PHOTONS; RADIO GALAXIES; GAMMA-RAYS; BL-LAC; MARKARIAN-501; ABSORPTION; RADIATION; UNIVERSE; JET AB The peak of the de-absorbed energy distribution of the TeV emitting blazars, all of the BL Lacertae (BL) class, can reach values Lip to similar to10 TeV. In the context of synchrotron-self Compton (SSC) models of relativistic uniformly moving blobs of plasma, such high energy peak emission can be reproduced only by assuming Doppler factors of delta similar to 50. However, such high values strongly disagree with the unification of FR 1 radio galaxies and BLs. Additionally, the recent detections of slow, possibly sub-luminal velocities in the sub-pc scale jets of the TeV BLs MKN 421 and MKN 501 suggest that the jets in these sources decelerate very early to mildly relativistic velocities (Gamma similar to a few). In this work we examine the possibility that the relativistic flows in the TeV BLs are longitudinally decelerating. In this case, modest Lorentz factors (Gamma similar to 15), decelerating down to values compatible with the recent radio interferometric observations, can reproduce the similar tofew TeV peak energy of these sources. Furthermore, such decelerating flows are shown to reproduce the observed broadband BL-FR 1 luminosity ratios. (C) 2004 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Georganopoulos, M (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Code 661, Greenbelt, MD 20771 USA. EM markos@milkyway.gsfc.nasa.gov NR 13 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD APR PY 2004 VL 48 IS 5-6 BP 403 EP 405 DI 10.1016/j.newar.2003.12.047 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 815ZK UT WOS:000221080000015 ER PT J AU Lamb, DQ Ricker, GR Atteia, JL Barraud, C Boer, M Braga, J Butler, N Cline, T Crew, GB Dezalay, JP Donaghy, TQ Doty, JP Dullighan, A Fenimore, EE Galassi, M Graziani, C Hurley, K Jernigan, JG Kawai, N Levine, A Manchanda, R Matsuoka, M Martel, F Monnelly, G Morgan, E Olive, JF Pizzichini, G Prigozhin, G Sakamoto, T Shirasaki, Y Suzuki, M Takagishi, K Tamagawa, T Torii, K Vanderspek, R Vedrenne, G Villasenor, J Woosley, SE Yamauchi, M Yoshida, A AF Lamb, DQ Ricker, GR Atteia, JL Barraud, C Boer, M Braga, J Butler, N Cline, T Crew, GB Dezalay, JP Donaghy, TQ Doty, JP Dullighan, A Fenimore, EE Galassi, M Graziani, C Hurley, K Jernigan, JG Kawai, N Levine, A Manchanda, R Matsuoka, M Martel, F Monnelly, G Morgan, E Olive, JF Pizzichini, G Prigozhin, G Sakamoto, T Shirasaki, Y Suzuki, M Takagishi, K Tamagawa, T Torii, K Vanderspek, R Vedrenne, G Villasenor, J Woosley, SE Yamauchi, M Yoshida, A TI Scientific highlights of the HETE-2 mission SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT 2nd VERITAS Symposium on TeV Astrophysics from Extragalactic Sources CY APR 24-26, 2003 CL Adler Planetarium & AStron Museum, Chicago, IL HO Adler Planetarium & AStron Museum DE gamma-rays : gamma-ray bursts; supernovae ID GAMMA-RAY BURSTS; EARLY OPTICAL-EMISSION; AFTERGLOW; GRB-021211; DISCOVERY; UNIVERSE; BRIGHT; ORIGIN AB The High Energy Explorer Satellite 2 (HETE-2) mission has been highly productive. It has observed more than 250 gamma-ray bursts (GRBs) so far. It is currently localizing 25-30 GRBs per year, and has localized 43 GRBs to date. Twenty-one of these localizations have led to the detection of X-ray, optical, or radio afterglows, and as of now, 11 of the bursts with afterglows have redshift determinations. HETE-2 has also observed more than 45 bursts from soft gamma-ray repeaters, and more than 700 X-ray bursts. C1 Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Tokyo Inst Technol, Tokyo 152, Japan. Tata Inst Fundamental Res, Dept Astron & Astrophys, Bombay 400005, Maharashtra, India. NASDA, Tokyo, Japan. CNR, IASF, Sez Bologna, Bologna, Italy. Natl Astron Observ, Tokyo 181, Japan. Miyazaki Univ, Fac Engn, Miyazaki 8892192, Japan. RIKEN, Inst Phys & Chem Res, Tokyo, Japan. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. Aoyama Gakuin Univ, Tokyo 150, Japan. RP Lamb, DQ (reprint author), Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. EM lamb@oddjob.uchicago.edu OI Boer, Michel/0000-0001-9157-4349 NR 35 TC 70 Z9 72 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD APR PY 2004 VL 48 IS 5-6 BP 423 EP 430 DI 10.1016/j.newar.2003.12.042 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 815ZK UT WOS:000221080000020 ER PT J AU Gehrels, N AF Gehrels, N TI The Swift gamma-ray burst mission SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT 2nd VERITAS Symposium on TeV Astrophysics from Extragalactic Sources CY APR 24-26, 2003 CL Adler Planetarium & AStron Museum, Chicago, IL HO Adler Planetarium & AStron Museum ID 28 FEBRUARY 1997; AFTERGLOW; REDSHIFT AB Swift is a first-of-its-kind multiwavelength transient observatory for GRB astronomy. It has the optimum capabilities for the next breakthroughs in determining the origin of GRBs and their afterglows, as well as using bursts to probe the early Universe. Swift will also perform the first sensitive hard X-ray survey of the sky. The mission is being developed by an international collaboration and consists of three instruments, the Burst Alert Telescope (BAT), the X-Ray Telescope (XRT), and the Ultraviolet and Optical Telescope (UVOT). The BAT, a wide-field gamma-ray detector, will detect >100 GRBs per year with a sensitivity five times that of BATSE. The sensitive narrow-field XRT and UVOT will be autonomously slewed to the burst location in 20-75 s to determine 0.3-5.0" positions and perform optical, UV, and X-ray spectrophotometry. Strong education/public outreach and follow-up programs will help to engage the public and astronomical community. The Swift launch is planned for 2004. (C) 2004 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Gehrels, N (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM gehrels@lheapop.gsfc.nasa.gov RI Gehrels, Neil/D-2971-2012 NR 13 TC 18 Z9 18 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD APR PY 2004 VL 48 IS 5-6 BP 431 EP 435 DI 10.1016/j.newar.2003.12.055 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 815ZK UT WOS:000221080000021 ER PT J AU Stecker, FW AF Stecker, FW TI Tests of quantum gravity and large extra dimensions models using high energy gamma-ray observations SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT 2nd VERITAS Symposium on TeV Astrophysics from Extragalactic Sources CY APR 24-26, 2003 CL Adler Planetarium & AStron Museum, Chicago, IL HO Adler Planetarium & AStron Museum DE gamma-rays; BL Lac objects; background radiation; infrared; Lorentz invariance; quantum gravity ID STAR-FORMATION; COSMIC-RAYS; CRAB-NEBULA; TEV; SPECTRUM; GALAXIES; LIMITS; MARKARIAN-501; ABSORPTION; RADIATION AB Observations of the multi-TeV spectra of the nearby BL objects Mkn 421 and Mkn 501 exhibit the high energy cutoffs predicted to be the result of intergalactic annihilation interactions, primarily with infrared photons having a flux level as determined by various astronomical observations. After correction for this absorption effect, the derived intrinsic spectra of these multi-TeV sources can be explained within the framework of simple synchrotron self-Compton emission models. Stecker and Glashow have shown that the existence of such annihilations via electron-positron pair production interactions up to an energy of 20 TeV puts strong constraints on Lorentz invariance violation. Such constraints have important implications for quantum gravity models as well as models involving large extra dimensions. We also discuss the implications of observations of high energy x-rays from the Crab Nebula on constraining quantum gravity models. (C) 2003 Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Stecker, FW (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. EM floyd.w.stecker@nasa.gov RI Stecker, Floyd/D-3169-2012 NR 43 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 EI 1872-9630 J9 NEW ASTRON REV JI New Astron. Rev. PD APR PY 2004 VL 48 IS 5-6 BP 437 EP 444 DI 10.1016/j.newar.2003.12.021 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 815ZK UT WOS:000221080000022 ER PT J AU Kazanas, D Georganopoulos, M Mastichiadis, A AF Kazanas, D Georganopoulos, M Mastichiadis, A TI The supercritical pile model of GRB: tapping the proton energy and getting the nu F-v peak at similar to 1 MeV SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT 2nd VERITAS Symposium on TeV Astrophysics from Extragalactic Sources CY APR 24-26, 2003 CL Adler Planetarium & AStron Museum, Chicago, IL HO Adler Planetarium & AStron Museum DE galaxies : active; quasars : general; radiation mechanisms : nonthermal; X-rays : galaxies ID GAMMA-RAY BURSTS; BLAZARS; ORIGIN; BATSE AB We propose a process by which the kinetic energy of the protons, that carry most of the energy of GRB relativistic blast waves (RBW), is converted explosively into relativistic electrons of the same Lorentz factor, which then produce the observed prompt gamma-ray emission of the burst. This conversion is the result of the combined effects of the reflection of photons produced within the flow by upstream located matter, their re-interception and conversion into e(+)e(-)-pairs on the RBW by the pgamma --> pe(+)e(-) reaction. This process depends on kinematic and dynamic thresholds; the Former depends on the RBW Lorentz factor Gamma while the second on the column density of the post shock matter to the pgamma --> e(+)e(-) reaction; this latter condition is in effect that of the criticality of a nuclear pile, hence the erminology. It is shown that, when operating near threshold, the resulting GRB spectrum produces its peak luminosity at energy (in the lab frame) E similar or equal to m(e)c(2) thereby providing an answer to this outstanding question of GRBs. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Athens, Dept Astron, Athens, Greece. RP Kazanas, D (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Code 661, Greenbelt, MD 20771 USA. EM kazanas@milkyway.gsfc.nasa.gov NR 10 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD APR PY 2004 VL 48 IS 5-6 BP 493 EP 495 DI 10.1016/j.newar.2003.12.009 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 815ZK UT WOS:000221080000033 ER PT J AU Thompson, DJ AF Thompson, DJ TI GLAST: GeV astronomy in a multiwavelength context SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT 2nd VERITAS Symposium on TeV Astrophysics from Extragalactic Sources CY APR 24-26, 2003 CL Adler Planetarium & AStron Museum, Chicago, IL HO Adler Planetarium & AStron Museum DE gamma-rays; GLAST AB The GLAST Large Area Telescope (LAT), successor to Energetic Gamma-ray Experiment Telescope (EGRET) on the Compton Observatory, will play an important role in multiwavelength studies during the second half of this decade. Operating at energies between 20 MeV and greater than 300 GeV with sensitivity 30 or more times greater than that of EGRET, the LAT will offer good spatial and time resolution over a large (> 2 sr) field of view. The LAT will bring insight to the whole range of high-energy gamma-ray phenomena, including bursts, active galactic nuclei, pulsars, supernova remnants. diffuse emission and unidentified sources. In essentially all cases, the maximum scientific return will come from coordinated (although not necessarily simultaneous) multiwavelength observations. Particularly with its planned scanning mode of operation, GLAST will have full sky coverage on relatively short time scales. The LAT team looks forward to cooperating with observers at other wavelengths. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Thompson, DJ (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. EM djt@egret.gsfc.nasa.gov RI Thompson, David/D-2939-2012 OI Thompson, David/0000-0001-5217-9135 NR 4 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD APR PY 2004 VL 48 IS 5-6 BP 543 EP 549 DI 10.1016/j.newar.2003.12.014 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 815ZK UT WOS:000221080000041 ER PT J AU Krimm, HA AF Krimm, HA CA Swift Team TI The Swift gamma-ray burst MIDEX mission SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT 2nd VERITAS Symposium on TeV Astrophysics from Extragalactic Sources CY APR 24-26, 2003 CL Adler Planetarium & AStron Museum, Chicago, IL HO Adler Planetarium & AStron Museum ID AFTERGLOW AB The Swift satellite, a NASA Medium-Class Explorer (MIDEX) mission scheduled for launch in July, 2004, is a multi-wavelength observatory for rapid-response observations of astrophysical transients. Swift is composed of three co-aligned telescopes covering an energy range from 7 eV (170 nm) to 150 keV. The Burst Alert Telescope (BAT) is a coded aperture hard X-ray imager, which serves as the gamma-ray burst (GRB) trigger for Swift. The Narrow Field Instruments (NFIs) are the Ultra-Violet/Optical Telescope (UVOT) and the X-ray Telescope (XRT). The Swift satellite has the ability to rapidly maneuver to point all there instruments at a bursting Source within a minute of detection. Rapid burst alerts will be distributed through the GRB Coordinates Network (GCN) and all Swift data will become public as soon as it is processed. Secondary science for Swift includes detecting astrophysical transients on time scales of from 5 min to several hours and immediately, alerting the astrophysical community of such events. Furthermore, the BAT instrument will be used for a high sensitivity hard X-ray all-sky survey which is expected to detect as many as 400 Active Galactic Nuclei (AGN). (C) 2004 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Krimm, HA (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM krimm@milkyway.gsfc.nasa.gov NR 15 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD APR PY 2004 VL 48 IS 5-6 BP 551 EP 557 DI 10.1016/j.newar.2003.12.045 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 815ZK UT WOS:000221080000042 ER PT J AU Mortensen, DG Wertheimer, AC Taylor, SG AF Mortensen, DG Wertheimer, AC Taylor, SG TI A compact water-heating system for thermally marking salmon otoliths SO NORTH AMERICAN JOURNAL OF AQUACULTURE LA English DT Article ID SURVIVAL AB We describe a compact water-heating system for thermally marking salmon otoliths during incubation. The system is portable and can be used to provide heated water for either streamside or instream incubators. The heating system consists of a small, propane-fired boiler and heat exchanger, a jet pump, a motorized set-point, a four-way mixing valve, and two circulating pumps. Warmed stream water exiting the heat exchanger is pumped to a head tank, mixed with ambient water to the desired temperature, and dispersed to the incubators, where some or all of the water can be recirculated or discarded. The mixing valve maintains a constant temperature in water flowing to the head tank based on a sensor feedback loop from the recovery tank. Using this system, we successfully marked approximately 800,000 pink salmon Oncorhynchus gorbuscha with no apparent adverse affects. Depending on incubation techniques, larger numbers of eggs or alevins could be marked. C1 Natl Marine Fisheries Serv, NOAA, Auke Bay Lab, Alaska Fisheries Sci Ctr, Juneau, AK 99801 USA. RP Mortensen, DG (reprint author), Natl Marine Fisheries Serv, NOAA, Auke Bay Lab, Alaska Fisheries Sci Ctr, 11305 Glacier Highway, Juneau, AK 99801 USA. EM don.mortensen@noaa.gov NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 1522-2055 J9 N AM J AQUACULT JI N. Am. J. Aqualcult. PD APR PY 2004 VL 66 IS 2 BP 85 EP 90 DI 10.1577/A03-011.1 PG 6 WC Fisheries SC Fisheries GA 817UY UT WOS:000221203600001 ER PT J AU Howell, LW AF Howell, LW TI Statistical properties of maximum likelihood estimators of power law spectra information SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE cosmic ray; simple power law; broken power law; maximum likelihood; spectral information; Cramer-Rao bound AB A maximum likelihood (ML) procedure was developed (Nucl. Instr. and Meth. Phys. Res. 480 (2-3) (2002) 739) for estimating the single parameter of a simple power law energy spectrum and generalized (Nucl. Instr. and Meth. Phys. Res. A 489 (2002) 422) to estimate the three spectral parameters of the broken power law energy spectrum from simulated detector responses and real cosmic-ray data. The statistical properties of the ML estimator are investigated in this paper and shown to have the three desirable properties: (P1) consistency (unbiased), (P2) efficiency (attains the Cramer-Rao minimum variance bound), and (P3) normally distributed, under a wide range of potential detector response functions. While simulation studies can easily determine if a given estimation procedure provides unbiased spectra information and whether or not the estimator is approximately normally distributed, attainment of the Cramer-Rao bound (CRB) can only be determined by calculating the CRB for an assumed energy spectrum-detector response function combination, which can be quite formidable in practice. However, the effort in calculating the CRB is very worthwhile because it provides: (1) the fundamental limit to the precision of spectral parameter determination for a cosmic-ray experiment, (2) the necessary means to compare the efficiency of competing estimation techniques and, (3) a stopping rule in the search for the best unbiased estimator. Consequently, the CRB for both the simple and broken power law energy spectra are derived herein and the conditions under which they are attained in practice are investigated. The impact of systematic errors in a detector on the efforts to determine the spectra information is also investigated. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, George C Marshall Space Flight Ctr, Sci Directorate, Huntsville, AL 35812 USA. RP Howell, LW (reprint author), NASA, George C Marshall Space Flight Ctr, Sci Directorate, SD50,POB 107, Huntsville, AL 35812 USA. EM leonard.w.howell@nasa.gov NR 10 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 1 PY 2004 VL 521 IS 2-3 BP 493 EP 511 DI 10.1016/j.nima.2003.11.193 PG 19 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZN UT WOS:000220607100021 ER PT J AU Pedelty, JA Morisette, JT Smith, JA AF Pedelty, JA Morisette, JT Smith, JA TI Comparison of Landsat-7 Enhanced Thematic Mapper Plus (ETM+) and Earth Observing One (EO-1) Advanced Land Imager SO OPTICAL ENGINEERING LA English DT Article DE remote sensing; space instrumentation; atmospheric correction AB We compare images from the Enhanced Thematic Mapper Plus (ETM+) sensor on Landsat-7 and the Advanced Land Imager (ALI) instrument on Earth Observing One (EO-1) over a test site in Rochester, New York. The site contains a variety of features, ranging from water of varying depths, deciduous/coniferous forest, grass fields, to urban areas. Nearly coincident cloud-free images were collected one minute apart on 25 August 2001. We also compare images of a forest site near Howland, Maine, that were collected on 7 September 2001. We atmospherically corrected each pair of images with the Second Simulation of the Satellite Signal in the Solar Spectrum (6S) atmosphere model, using aerosol optical thickness and water vapor column density measured by in situ Cimel sun photometers within the Aerosol Robotic Network (AERONET), along with ozone density derived from the Total Ozone Mapping Spectrometer (TOMS) on the Earth Probe satellite. We present true-color composites from each instrument that show excellent qualitative agreement between the multispectral sensors, along with gray-scale images that demonstrate a significantly improved ALI panchromatic band. We quantitatively compare ALI and ETM+ reflectance spectra of a grassy field in Rochester and find less than or equal to6% differences in the visible/near infrared and similar to2% differences in the short-wave infrared. Spectral comparisons of forest sites in Rochester and Howland yield similar percentage agreement except for band 1, which has very low reflectance. Principal component analyses and comparison of normalized difference vegetation index histograms for each sensor indicate that the ALI is able to reproduce the information content in the ETM+ but with superior signal-to-noise performance due to its increased 12-bit quantization. (C) 2004 Society of Photo-Optical Instrumentation Engineers. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Pedelty, JA (reprint author), NASA, Goddard Space Flight Ctr, Code 923, Greenbelt, MD 20771 USA. NR 7 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD APR PY 2004 VL 43 IS 4 BP 954 EP 962 DI 10.1117/1.1651556 PG 9 WC Optics SC Optics GA 814IN UT WOS:000220968500028 ER PT J AU Loncar, M Hochberg, M Scherer, A Qiu, YM AF Loncar, M Hochberg, M Scherer, A Qiu, YM TI High quality factors and room-temperature lasing in a modified single-defect photonic crystal cavity SO OPTICS LETTERS LA English DT Article ID QUANTUM-DOT; LASER; MODE; SLAB AB We propose and analyze a new photonic crystal cavity design that supports a dipole mode with a quality factor greater than 20,000. Such a high quality factor is obtained by precise tuning of the cavity length with minimal disruption of the surrounding photonic crystal. A fabrication procedure based on dry etching of InGaAsP material in HI/H-2/Ar is used to demonstrate photonic crystal lasers with smooth and straight sidewalls. These room-temperature lasers concentrate optical energy in air and are suitable for use as tunable lasers and chemical sensors. (C) 2004 Optical Society of America. C1 CALTECH, Dept Elect Engn & Appl Phys, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, In Situ Technol & Expt Syst Sect, Pasadena, CA 91109 USA. RP Loncar, M (reprint author), CALTECH, Dept Elect Engn & Appl Phys, MS 136-93, Pasadena, CA 91125 USA. EM loncar@deas.harvard.edu NR 13 TC 36 Z9 36 U1 2 U2 11 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD APR 1 PY 2004 VL 29 IS 7 BP 721 EP 723 DI 10.1364/OL.29.000721 PG 3 WC Optics SC Optics GA 805JN UT WOS:000220362700021 PM 15072370 ER PT J AU Minina, NY Kolokolov, KI Beneslavski, SD Bogdanov, EV Polyanskiy, AV Savin, AM Hansen, OP AF Minina, NY Kolokolov, KI Beneslavski, SD Bogdanov, EV Polyanskiy, AV Savin, AM Hansen, OP TI Transformation of the Fermi surface and anisotropy phenomena in 2D hole gas at GaAs/AlxGa1-xAs heterointerface under uniaxial stress SO PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES LA English DT Article; Proceedings Paper CT 15th International Conference on Electronic Properties of Two-Dimensional Systems (EP2DS-15) CY JUL 14-18, 2003 CL Nara, JAPAN DE heterostructure; band structure; electronic transport; optical properties; uniaxial AB By numerical calculation the Fermi surface of two-dimensional (2D) holes at p-GaAs/AlxGal-x As heterointerface is found to become strongly anisotropic under the application of in-plane uniaxial compression. This uniaxial stress-induced anisotropy of the energy spectrum reveals in more that two times increase of 2D hole mobility anisotropy (at uniaxial compression about 5 kbar), that is experimentally detected in such heterostructures. It leads also to considerable anisotropy of far-infrared absorption spectrum; absorption of light with polarization perpendicular to the direction of compression is smaller that the absorption of light with polarization parallel to the direction of compression. (C) 2003 Elsevier B.V. All rights reserved. C1 Moscow MV Lomonosov State Univ, Fac Phys, Moscow 119899, Russia. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. Helsinki Univ Technol, Low Temp Lab, FIN-02015 Espoo, Finland. Niels Bohr Inst, Orsted Lab, DK-2100 Copenhagen, Denmark. RP Minina, NY (reprint author), Moscow MV Lomonosov State Univ, Fac Phys, Moscow 119899, Russia. EM min@mig.phys.msu.ru RI Bogdanov, Evgeny/G-5535-2010; Savin, Alexander/J-2922-2012; Minina, Natalia/G-5540-2010 OI Savin, Alexander/0000-0001-9894-1180; Minina, Natalia/0000-0001-9094-5910 NR 4 TC 1 Z9 1 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1386-9477 J9 PHYSICA E JI Physica E PD APR PY 2004 VL 22 IS 1-3 BP 373 EP 376 DI 10.1016/j.physe.2003.12.024 PG 4 WC Nanoscience & Nanotechnology; Physics, Condensed Matter SC Science & Technology - Other Topics; Physics GA 816WU UT WOS:000221140800090 ER PT J AU Li, J Ning, CZ AF Li, J Ning, CZ TI Collective excitations in InAs quantum well intersubband transitions SO PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES LA English DT Article; Proceedings Paper CT 15th International Conference on Electronic Properties of Two-Dimensional Systems (EP2DS-15) CY JUL 14-18, 2003 CL Nara, JAPAN DE many-body effects; intersubband transitions; carrier scattering; Fermi edge singularity; intersubband plasmon ID ELECTRON-GAS; TEMPERATURE; LINEWIDTH; EXCHANGE; DENSITY AB Intersubband transitions in semiconductor quantum well are studied using a density matrix theory that goes beyond the Hartree-Fock approximation by including the full second order electron-electron scattering terms in the polarization equation for the first time. Even though the spectral features remain qualitatively similar to the results obtained with dephasing rate approximation, significant quantitative changes result from such a more detailed treatment of dephasing. More specifically, we show how the interplay of the two fundamental collective excitations, the Fermi-edge singularity and the intersubband plasmon, leads to significant changes in lineshape as the electron density varies. (C) 2003 Published by Elsevier B.V. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Ning, CZ (reprint author), NASA, Ames Res Ctr, Ctr Nanotechnol, MS 229-1, Moffett Field, CA 94035 USA. EM cning@mail.arc.nasa.gov RI Ning, C. Z./D-4699-2009 OI Ning, C. Z./0000-0003-4583-8889 NR 21 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1386-9477 J9 PHYSICA E JI Physica E PD APR PY 2004 VL 22 IS 1-3 BP 628 EP 631 DI 10.1016/j.physe.2003.12.086 PG 4 WC Nanoscience & Nanotechnology; Physics, Condensed Matter SC Science & Technology - Other Topics; Physics GA 816WU UT WOS:000221140800152 ER PT J AU Ramirez-Serrano, J DeGraffenreid, W Weiner, J Tiesinga, E Julienne, PS AF Ramirez-Serrano, J DeGraffenreid, W Weiner, J Tiesinga, E Julienne, PS TI Beam-loss spectroscopy of cold collisions in a bright sodium beam SO PHYSICAL REVIEW A LA English DT Article ID 2-COLOR PHOTOASSOCIATION SPECTROSCOPY; SCATTERING LENGTHS; COOLED ATOMS; IONIZATION; STATE; LIGHT AB We report beam-loss photoassociation (PA) spectra of cold collisions within a slow, bright Na atom beam near the D-1 resonance line. The high collimation and brilliance of the atomic beam permits the detection of atomic fluorescence loss resulting from the photoassociation of cold sodium atoms. The results show that even at high PA laser intensities, where strong coupling of the colliding atoms to the optical field might obscure spectral features, vibrational and rotational progressions are surprisingly well resolved. We attribute the conservation of narrow spectral features to the properties of the saturated line shapes and to the unconventional collision energy distribution in one-dimensional (1D) single-beam collisions compared to 3D collisions in a gas cell. C1 Univ Maryland, Lab Atom Mol & Opt Sci & Engn, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Atom Phys Div, Gaithersburg, MD 20899 USA. RP CALTECH, Jet Prop Lab, Quantum Sci Grp, 4800 Oak Grove Dr,MS 298-100, Pasadena, CA 91109 USA. RI Weiner, John/C-1065-2008; Julienne, Paul/E-9378-2012 OI Julienne, Paul/0000-0002-5494-1442 NR 31 TC 4 Z9 4 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD APR PY 2004 VL 69 IS 4 AR 042708 DI 10.1103/PhysRevA.69.042708 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 818WY UT WOS:000221276400072 ER PT J AU Dholakia, GR Fan, W Koehne, J Han, J Meyyappan, M AF Dholakia, GR Fan, W Koehne, J Han, J Meyyappan, M TI Transport in self-assembled molecular wires: Effect of packing and order SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC DEVICE; MONOLAYERS; SURFACES; GOLD AB We show that orientation, packing, and order play a vital role in determining the current-voltage (I-V) characteristics of self-assembled molecular wires, an important issue which can affect the performance of molecular electronic devices. By topographic and tunneling spectroscopic studies on monolayers of a molecule assembled with and without molecular order, we show that competing forces due to the electric field, intermolecular interactions, tip-molecule physisorption, and substrate-molecule chemisorption influence the transport measurements and its reproducibility. We also find that asymmetry in the I-V is caused both by the molecular structure and the contact geometry. C1 NASA, Ctr Nanotechnol, Ames Res Ctr, Moffett Field, CA 94035 USA. ELORET, Sunnyvale, CA 94087 USA. RP Dholakia, GR (reprint author), NASA, Ctr Nanotechnol, Ames Res Ctr, Moffett Field, CA 94035 USA. EM gdholakia@mail.arc.nasa.gov NR 18 TC 14 Z9 14 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD APR PY 2004 VL 69 IS 15 AR 153402 DI 10.1103/PhysRevB.69.153402 PG 4 WC Physics, Condensed Matter SC Physics GA 820YT UT WOS:000221426800023 ER PT J AU Guillaume, A Schneiderman, JF Delsing, P Bozler, HM Echternach, PM AF Guillaume, A Schneiderman, JF Delsing, P Bozler, HM Echternach, PM TI Free evolution of superposition states in a single Cooper pair box SO PHYSICAL REVIEW B LA English DT Article ID MACROSCOPIC QUANTUM STATES; JOSEPHSON-JUNCTION; ELECTRON TRANSISTOR; QUBITS AB We have fabricated a single Cooper-pair box (SCB) in close proximity to a single electron transistor (SET) operated in the radio-frequency mode (RF-SET) with an inductor and capacitor lithographed directly on chip. The RF-SET was used to measure the charge state of the SCB revealing a 2e periodic charge quantization. We performed spectroscopy measurements to extract the charging energy (E-C) and the Josephson coupling energy (E-J). Control of the temporal evolution of the quantum charge state was achieved by applying fast dc pulses to the SCB gate. The dephasing and relaxation times were extracted from these measurements. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ So Calif, Dept Phys & Astron, Los Angeles, CA 90089 USA. Chalmers Univ Technol, S-41296 Gothenburg, Sweden. RP Guillaume, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Delsing, Per/F-7288-2010; Schneiderman, Justin/D-4508-2013 OI Delsing, Per/0000-0002-1222-3506; Schneiderman, Justin/0000-0002-4441-2360 NR 20 TC 26 Z9 26 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD APR PY 2004 VL 69 IS 13 AR 132504 DI 10.1103/PhysRevB.69.132504 PG 4 WC Physics, Condensed Matter SC Physics GA 818XP UT WOS:000221278100028 ER PT J AU Srivastava, D Menon, M Daraio, C Jin, S Sadanadan, B Rao, AM AF Srivastava, D Menon, M Daraio, C Jin, S Sadanadan, B Rao, AM TI Vacancy-mediated mechanism of nitrogen substitution in carbon nanotubes SO PHYSICAL REVIEW B LA English DT Article ID BORON-NITRIDE NANOTUBES; MOLECULAR-DYNAMICS SCHEME; GROWTH; FULLERENES; FILAMENTS AB Nitrogen substitution reaction in a graphene sheet and carbon nanotubes of different diameter are investigated using the generalized tight-binding molecular dynamics method. The formation of a vacancy in curved graphene sheet or a carbon nanotube is found to cause a curvature dependent local reconstruction of the surface. Our simulations and analysis show that vacancy mediated N substitution (rather than N chemisorption) is favored on the surface of nanotubes with diameter larger than 8 nm. This predicted value of the critical minimum diameter for N incorporation is confirmed by experimental results presented on nitrogen-doped multiwalled nanotubes with approximate to5 at. % nitrogen prepared by the thermal chemical vapor deposition process. C1 NASA, Ames Res Ctr, CSC, Moffett Field, CA 94035 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Univ Kentucky, Ctr Computat Sci, Lexington, KY 40506 USA. Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. Clemson Univ, Dept Phys & Astron, Clemson, SC 29634 USA. RP Srivastava, D (reprint author), NASA, Ames Res Ctr, CSC, Mail Stop T27-A1, Moffett Field, CA 94035 USA. EM deepak@nas.nasa.gov; super250@pop.uky.edu; arao@CLEMSON.EDU RI Daraio, Chiara/N-2170-2015 OI Daraio, Chiara/0000-0001-5296-4440 NR 24 TC 32 Z9 32 U1 1 U2 14 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD APR PY 2004 VL 69 IS 15 AR 153414 DI 10.1103/PhysRevB.69.153414 PG 4 WC Physics, Condensed Matter SC Physics GA 820YT UT WOS:000221426800035 ER PT J AU Johnson, TV AF Johnson, TV TI A look at the Galilean satellites after the Galileo mission SO PHYSICS TODAY LA English DT Article ID INFRARED MAPPING SPECTROMETER; GEOLOGICAL EVIDENCE; SUBSURFACE OCEAN; WATER-ICE; EUROPA; GANYMEDE; ATMOSPHERE; SPACECRAFT; CALLISTO; IO C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. RP Johnson, TV (reprint author), CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. NR 15 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD APR PY 2004 VL 57 IS 4 BP 77 EP 83 DI 10.1063/1.1752426 PG 7 WC Physics, Multidisciplinary SC Physics GA 809FM UT WOS:000220622600029 ER PT J AU Binzel, RP Birlan, M Bus, SJ Harris, AW Rivkin, AS Fornasier, S AF Binzel, RP Birlan, M Bus, SJ Harris, AW Rivkin, AS Fornasier, S TI Spectral observations for near-Earth objects including potential target 4660 Nereus: Results from Meudon remote observations at the NASA Infrared Telescope Facility (IRTF) SO PLANETARY AND SPACE SCIENCE LA English DT Article DE remote observation; spectroscopy; asteroid; space mission ID ASTEROID SPECTROSCOPIC SURVEY; PHASE-II; SPECTROGRAPH; RESOLUTION AB We present visible and near-infrared spectral measurements for the highly accessible spacecraft target 4660 Nereus and three additional near-Earth objects displaying diverse color characteristics. All near-infrared measurements were carried out during the first remote observing operations between the Observatoire de Paris at Meudon and Mauna Kea, Hawaii. From Meudon, we had fine pointing and guiding control of the NASA Infrared Telescope Facility 3.0-m telescope and the near-infrared spectrograph "SpeX" to measure asteroid spectra in the range 0.8-2.4 mum. The efficiency of the observation was virtually the same as if the observers had been on location. We combine our near-infrared results with complementary 0.4-0.9 mum spectral measurements. Nereus is found to be a rare Xe-type asteroid with a composition that may be analogous to very high albedo enstatite achondrite (aubrite) meteorites, leading to a diameter estimate of less than 0.5 km. 1685 Toro displays a classic S-type spectrum while a steeper visible wavelength slope and a less pronounced 1 mum absorption feature for 1943 Anteros places it in the L-class. Also unusual is the apparent olivine-rich spectrum for 4142 Dersu-Uzala, which is classified as an A-type. (C) 2003 Elsevier Ltd. All rights reserved. C1 MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. Observ Paris, F-92195 Meudon, France. Inst Astron, Hilo, HI 96720 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Astron Dept Padova, I-35122 Padua, Italy. RP Binzel, RP (reprint author), MIT, Dept Earth Atmospher & Planetary Sci, Mail Stop 54-410, Cambridge, MA 02139 USA. EM rpb@mit.edu RI Rivkin, Andrew/B-7744-2016; BIRLAN, Mirel/B-5283-2011 OI Rivkin, Andrew/0000-0002-9939-9976; NR 25 TC 22 Z9 22 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR PY 2004 VL 52 IS 4 BP 291 EP 296 DI 10.1016/j.pss.2003.10.003 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 780MQ UT WOS:000189385400004 ER PT J AU Di Martino, M Montebugnoli, S Cevolani, G Ostro, S Zaitsev, A Righini, S Saba, L Poppi, S Delbo, M Orlati, A Maccaferri, G Bortolotti, C Gavrik, A Gavrik, Y AF Di Martino, M Montebugnoli, S Cevolani, G Ostro, S Zaitsev, A Righini, S Saba, L Poppi, S Delbo, M Orlati, A Maccaferri, G Bortolotti, C Gavrik, A Gavrik, Y TI Results of the first Italian planetary radar experiment SO PLANETARY AND SPACE SCIENCE LA English DT Article DE asteroids; radar; remote sensing; spectroscopy AB We describe the first intercontinental planetary radar initiative undertaken in Italy. We present the results of the observations of Near-Earth Asteroid (NEA) 33342 (1998 WT24), performed in December 2001 using the bistatic configurations Goldstone-Medicina and Evpatoria-Medicina, with the 32-m Medicina dish used to receive echoes in both cases. The experiment goal was to characterise the system for radar follow-up observations of NEA and artificial orbiting debris, in the framework of a feasibility study which aims at using the Sardinia Radio Telescope, at present under construction, also as a planetary radar facility. (C) 2003 Elsevier Ltd. All rights reserved. C1 Osserv Astron Torino, INAF, I-10025 Pino Torinese, Italy. CNR, Ist Radioastron, I-40059 Bologna, Italy. CNR, ISAC, I-40129 Bologna, Italy. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RAS, IRE, Fryazino 141190, Russia. Osservatorio Astron Cagliari, INAF, I-09012 Cagliari, Italy. RP Di Martino, M (reprint author), Osserv Astron Torino, INAF, Strada Osservatorio 20, I-10025 Pino Torinese, Italy. EM dimartino@to.astro.it OI Orlati, Andrea/0000-0001-8737-255X; Poppi, Sergio/0000-0002-4698-2607; Righini, Simona/0000-0001-7332-5138 NR 5 TC 7 Z9 7 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR PY 2004 VL 52 IS 4 BP 325 EP 330 DI 10.1016/j.pss.2003.09.001 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 780MQ UT WOS:000189385400007 ER PT J AU Burgdorf, MJ Orton, GS Encrenaz, T Davis, GR Sidher, SD Lellouch, E Swinyard, BM AF Burgdorf, MJ Orton, GS Encrenaz, T Davis, GR Sidher, SD Lellouch, E Swinyard, BM TI The far-infrared spectra of Jupiter and Saturn SO PLANETARY AND SPACE SCIENCE LA English DT Article; Proceedings Paper CT Euroconference on Jupiter after Galileo and Cassini CY JUN, 2002 CL Lisbon, PORTUGAL SP European Commiss, Human Potential Programme, Portuguese Fdn Sci & Technol, Apoio Programa Operac Cienc Tecnol, Inovacao Quadro Comunitar Apoio III, Portugues Inst Earth & Space Sci, European Space Agcy, Natl Aeronaut & Space Adm, Everest Coatings, Critical Software, Calouste Gulbenkian Fdn, Univ Lisbon, Ctr Astronomy & Astrophys, Lisbon Astronom Observatory, Univ Lisbon, Fac Sci DE abundances; atmospheres; infrared observations; Jovian planets; spectroscopy ID ISO-SWS OBSERVATIONS; WAVELENGTH SPECTROMETER; PHOSPHINE LINES; AMMONIA ICE; SUBMILLIMETER; LWS; PH3; NH3; SPECTROSCOPY; PERFORMANCE AB We present far-infrared, disk-averaged spectra of Jupiter and Saturn that were measured with the Long Wavelength Spectrometer aboard the Infrared Space Observatory. The Long Wavelength Spectrometer covered the wavelength region between 43 and 197 mum and achieved in grating mode a resolving power of 150-300. The spectra observed in the far infrared are compared to synthetic spectra calculated from atmospheric radiative transfer models using expected values for the constituent vertical concentration profiles. Rotational transitions of ammonia and phosphine are responsible for the broad absorption features observed: Strong ammonia absorption manifolds are obvious against the background continuum slope, appearing at 63, 72, 84, 101 and 125 put in both Jupiter and Saturn. Also phosphine absorption features are clearly present; we found them at the expected wavelengths of 113 and 141 mum in both planets and at 81, 87, 94, 103, 126 and 160 mum on Saturn only. Our findings are in good agreement with the results obtained with other instruments, in particular the Short Wavelength Spectrometer of the Infrared Space Observatory. On Jupiter we obtained the best fit to the observations with models having an NH3 mixing ratio of 2 x 10(-4). We fitted Saturn's measured spectrum with models where the ammonia mixing ratio amounted to 10-4. For phosphine we found an abundance of 7(-3.5)(+7) x 10(-6) in the troposphere of this planet. (C) 2003 Elsevier Ltd. All rights reserved. C1 CALTECH, SIRTF Sci Ctr, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Observ Paris, LESIA, F-92195 Meudon, France. Joint Astron Ctr, Hilo, HI 96720 USA. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. RP Burgdorf, MJ (reprint author), CALTECH, SIRTF Sci Ctr, Pasadena, CA 91125 USA. EM burgdorf@ipac.caltech.edu; go@orton.jpl.nasa.gov; therese.encrenaz@obspm.fr; g.davis@jach.hawaii.edu; s.d.sidher@rl.ac.uk; emmanuel.lellouch@obspm.fr; b.m.swinyard@rl.ac.uk NR 31 TC 9 Z9 10 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR-MAY PY 2004 VL 52 IS 5-6 BP 379 EP 383 DI 10.1016/j.pss.2003.07.004 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807CJ UT WOS:000220479300005 ER PT J AU Wong, MH Bjoraker, GL Smith, MD Flasar, FM Nixon, CA AF Wong, MH Bjoraker, GL Smith, MD Flasar, FM Nixon, CA TI Identification of the 10-mu m ammonia ice feature on Jupiter SO PLANETARY AND SPACE SCIENCE LA English DT Article; Proceedings Paper CT Euroconference on Jupiter after Galileo and Cassini CY JUN, 2002 CL Lisbon, PORTUGAL SP European Commiss, Human Potential Programme, Portuguese Fdn Sci & Technol, Apoio Programa Operac Cienc Tecnol, Inovacao Quadro Comunitar Apoio III, Portugues Inst Earth & Space Sci, European Space Agcy, Natl Aeronaut & Space Adm, Everest Coatings, Critical Software, Calouste Gulbenkian Fdn, Univ Lisbon, Ctr Astronomy & Astrophys, Lisbon Astronom Observatory, Univ Lisbon, Fac Sci DE atmospheres; Cassini; ices; infared spectroscopy ID ATMOSPHERE; SCATTERING; CLOUDS; AEROSOLS AB We present the first detection of NH3 ice in the thermal infrared in Jupiter's atmosphere using Cassini CIRS observations in the 10-mum region obtained on 31 December 2000 and I January 2001. We identify a brightness temperature difference alphadrop T-B(1040 cm(-1)) - T-B(1060 cm(-1)) as an indicator of spectrally identifiable NH3 ice, where 1040 cm(-1) is an adjacent continuum region and 1060 cm(-1) is the NH3 ice feature. Higher values of alpha imply a stronger NH3 ice signature in the spectrum. Using midlatitude zonally averaged CIRS spectra, we demonstrate systematic spatial variations in alpha, with the highest values at the equator and near 23degreesN. In one CIRS spectral average (covering 22-25degreesN and 140-240degreesW), our radiative transfer models are consistent with an optical depth of 0.75 +/- 0.25 for NH3 ice particles modeled as randomly oriented 4:1 prolate spheroids (volume equivalent radius = 0.79 mum). Particles larger or smaller than 1 mum by about a factor of 2 would be unable to duplicate the observed NH3 ice feature at 1060 cm(-1): absorption due to larger particles is excessively broadened, and absorption due to smaller particles is hidden by NH3 gas absorption at 1067 cm(-1). We also modeled an average spectrum for a second region on Jupiter (14-17degreesN and 10-70degreesW), finding an upper limit of tau = 0.2 for the same NH3 ice particle type. The choice of prolate spheroid particles is based on laboratory studies of NH3 ice aerosols, although 1-mum Mie-scattering spheres would also have detectable signatures at 1060 cm(-1). We model the 1-mum NH3 ice cloud with a particle-to-gas scale height ratio H-p/H-g = 1. For both CIRS spectra analyzed, the spectrum at frequencies greater than 1100 cm(-1) also requires a second cloud with essentially grey absorption, which we modeled using 10-mum NH3 ice spheres distributed with H-p/H-g = 1/8 and a cloud base at 790 mbar. (C) 2003 Elsevier Ltd. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RP Wong, MH (reprint author), NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Code 690, Greenbelt, MD 20771 USA. EM mikewong@astro.berkeley.edu RI Nixon, Conor/A-8531-2009; Flasar, F Michael/C-8509-2012; Smith, Michael/C-8875-2012; Bjoraker, Gordon/D-5032-2012 OI Nixon, Conor/0000-0001-9540-9121; NR 30 TC 37 Z9 37 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR-MAY PY 2004 VL 52 IS 5-6 BP 385 EP 395 DI 10.1016/j.pss.2003.06.005 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807CJ UT WOS:000220479300006 ER PT J AU Roos-Serote, M Atreya, SK Wong, MK Drossart, P AF Roos-Serote, M Atreya, SK Wong, MK Drossart, P TI On the water abundance in the atmosphere of Jupiter SO PLANETARY AND SPACE SCIENCE LA English DT Article; Proceedings Paper CT Euroconference on Jupiter after Galileo and Cassini CY JUN, 2002 CL Lisbon, PORTUGAL SP European Commiss, Human Potential Programme, Portuguese Fdn Sci & Technol, Apoio Programa Operac Cienc Tecnol, Inovacao Quadro Comunitar Apoio III, Portugues Inst Earth & Space Sci, European Space Agcy, Natl Aeronaut & Space Adm, Everest Coatings, Critical Software, Calouste Gulbenkian Fdn, Univ Lisbon, Ctr Astronomy & Astrophys, Lisbon Astronom Observatory, Univ Lisbon, Fac Sci DE Jupiter; atmosphere; composition; structure; infrared data ID PROBE NEPHELOMETER EXPERIMENT; CLOUD STRUCTURE; HOT-SPOTS; JOVIAN ATMOSPHERE; VOYAGER IRIS; GALILEO; ORIGIN; 5-MU-M; SPECTROMETER; AMMONIA AB In this paper, we attempt to place constraints on the possible global abundance of water and the average vertical cloud structure in the atmosphere of Jupiter. Based on the analysis of the Galileo Near-Infrared Mapping Spectrometer data, we find that in the atmosphere of Jupiter down to 6-8 bar, particularly in the North Equatorial Belt (NEB) region, the overall O/H ratio is compatible with one or more times the solar value of this ratio. We also find that if water clouds form at the levels where they are expected from thermochemical equilibrium calculations for a given deep O/H ratio, then subsolar values of the O/H ratio cannot be reconciled with the analyzed data. However, these results are dependent on the model atmosphere, in particular the detailed vertical distribution of cloud opacity. Therefore, they should be considered with care, until new observations on the vertical cloud structure become available. The water vapor mixing ratio in the NEB displays large spatial variations. The same set of data yield subsaturated mixing ratios of ammonia to atmospheric levels of about 4 bar. This depletion of ammonia to great depths, as seen by the Galileo Probe in the hot spot where it entered, appears to be a common phenomenon in the entire NEB. (C) 2003 Elsevier Ltd. All rights reserved. C1 Lisbon Astron Observ, P-1349018 Lisbon, Portugal. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Observ Paris, F-92195 Meudon, France. RP Roos-Serote, M (reprint author), Lisbon Astron Observ, P-1349018 Lisbon, Portugal. EM roos@oal.ul.pt NR 42 TC 16 Z9 16 U1 2 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR-MAY PY 2004 VL 52 IS 5-6 BP 397 EP 414 DI 10.1016/j.pss.2003.06.007 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807CJ UT WOS:000220479300007 ER PT J AU Gladstone, GR Pryor, WR Tobiska, WK Stewart, AIF Simmons, KE Ajello, JM AF Gladstone, GR Pryor, WR Tobiska, WK Stewart, AIF Simmons, KE Ajello, JM TI Constraints on Jupiter's hydrogen corona from Galileo UVS observations SO PLANETARY AND SPACE SCIENCE LA English DT Article; Proceedings Paper CT Euroconference on Jupiter after Galileo and Cassini CY JUN, 2002 CL Lisbon, PORTUGAL SP European Commiss, Human Potential Programme, Portuguese Fdn Sci & Technol, Apoio Programa Operac Cienc Tecnol, Inovacao Quadro Comunitar Apoio III, Portugues Inst Earth & Space Sci, European Space Agcy, Natl Aeronaut & Space Adm, Everest Coatings, Critical Software, Calouste Gulbenkian Fdn, Univ Lisbon, Ctr Astronomy & Astrophys, Lisbon Astronom Observatory, Univ Lisbon, Fac Sci DE Jupiter; Lyman alpha; airglow ID UPPER-ATMOSPHERE; PRECIPITATION AB During Galileo orbits Cl 0 and El 1, the Ultraviolet Spectrometer (UVS) obtained H Lyalpha scans at low latitudes across the disk of Jupiter from a phase angle of 90-109degrees and a distance of 18-21 jovian radii. Jupiter's nightside Lyalpha brightness was about 0.5 kR, approximately half as bright as interplanetary space. From the nightside to the dayside, the Lyalpha brightness rose to a peak of similar to 15 kR near the sub-solar limb and then dropped sharply to interplanetary brightness levels. On orbit C10 three disk scans were obtained (near 30degreesN latitude, 20degreesS latitude, and along the equator), while a single equatorial scan was made on orbit E11. The steep falloff in Lyalpha brightness at the sub-solar point provides a strong constraint on the distribution of atomic hydrogen in the upper atmosphere. All disk scans are reasonably well fit by a resonance line radiative transfer model which assumes a total H column density of similar to 10(17) cm(-2) and a temperature profile consistent with the Galileo probe results with an exospheric temperature of 940 K. However, we find that the inclusion of a small amount of "hot" hydrogen, with an abundance described by a Chapman profile, can substantially improve the fit to the UVS limb scan data. Exactly such a hot hydrogen component is expected in the upper atmosphere of Jupiter, and has been previously invoked to explain observations of the jovian Lyalpha line profile made from Earth orbit. The best fits to the UVS data occur with a hot H column density that is 0.1% of the ambient H column, with an effective temperature of 25, 000 K and a topside scale height of 1000 km (in our empirical representation, the hot H scale height is unrelated to the hot H temperature). Other combinations of column abundance and the effective temperature can also provide good fits to the data. As long as the hot H is located above the homopause, there is no strong dependence on the height of the Chapman profile. (C) 2003 Elsevier Ltd. All rights reserved. C1 SW Res Inst, San Antonio, TX 78238 USA. Cent Arizona Univ, Coolidge, AZ USA. Space Environm Technol, Pacific Palisades, CA USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. CALTECH, Jet Propuls Lab, Pasadena, CA USA. RP Gladstone, GR (reprint author), SW Res Inst, 6220 Culebra Rd, San Antonio, TX 78238 USA. EM rgladstone@swri.edu NR 19 TC 10 Z9 10 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR-MAY PY 2004 VL 52 IS 5-6 BP 415 EP 421 DI 10.1016/j.pss.2003.06.012 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807CJ UT WOS:000220479300008 ER PT J AU Russell, CT Coradini, A Christensen, U De Sanctis, MC Feldman, WC Jaumann, R Keller, HU Konopliv, AS McCord, TB McFadden, LA McSween, HY Mottola, S Neukum, G Pieters, CM Prettyman, TH Raymond, CA Smith, DE Sykes, MV Williams, BG Wise, J Zuber, MT AF Russell, CT Coradini, A Christensen, U De Sanctis, MC Feldman, WC Jaumann, R Keller, HU Konopliv, AS McCord, TB McFadden, LA McSween, HY Mottola, S Neukum, G Pieters, CM Prettyman, TH Raymond, CA Smith, DE Sykes, MV Williams, BG Wise, J Zuber, MT TI Dawn: A journey in space and time SO PLANETARY AND SPACE SCIENCE LA English DT Article; Proceedings Paper CT Euroconference on Jupiter after Galileo and Cassini CY JUN, 2002 CL Lisbon, PORTUGAL SP European Commiss, Human Potential Programme, Portuguese Fdn Sci & Technol, Apoio Programa Operac Cienc Tecnol, Inovacao Quadro Comunitar Apoio III, Portugues Inst Earth & Space Sci, European Space Agcy, Natl Aeronaut & Space Adm, Everest Coatings, Critical Software, Calouste Gulbenkian Fdn, Univ Lisbon, Ctr Astronomy & Astrophys, Lisbon Astronom Observatory, Univ Lisbon, Fac Sci DE Ceres; main belt asteroids; protoplanets; solar system evolution; Vesta ID ASTEROID 4 VESTA; EUCRITE PARENT BODY; HF-W CHRONOMETRY; SOLAR-SYSTEM; REFLECTANCE SPECTRA; MAGNETIC-FIELD; CORE FORMATION; 1 CERES; IMAGING SPECTROMETER; INTERNAL STRUCTURE AB By successively orbiting both 4 Vesta and I Ceres the Dawn mission directly addresses the long-standing goals of understanding the origin and evolution of the solar system. Ceres and Vesta are two complementary terrestrial protoplanets (one apparently "wet" and the other "dry"), whose accretion was probably terminated by the formation of Jupiter. They provide a bridge in our understanding between the rocky bodies of the inner solar system and the icy bodies of the outer solar system. Ceres appears to be undifferentiated while Vesta has experienced significant heating and likely differentiation. Both formed very early in the history of the solar system and while suffering many impacts have remained intact, thereby retaining a record of events and processes from the time of planet formation. Detailed study of the geophysics and geochemistry of these two bodies provides critical benchmarks for early solar system conditions and processes that shaped its subsequent evolution. Dawn provides the missing context for both primitive and evolved meteoritic data, thus playing a central role in understanding terrestrial planet formation and the evolution of the asteroid belt. Dawn is to be launched in May 2006 arriving at Vesta in 2010 and Ceres in 2014, stopping at each to make I I months of orbital measurements. The spacecraft uses solar electric propulsion, both in cruise and in orbit, to make most efficient use of its xenon propellant. The spacecraft carries a framing camera, visible and infrared mapping spectrometer, gamma ray/neutron spectrometer, magnetometer, and radio science. (C) 2003 Elsevier Ltd. All rights reserved. C1 Univ Calif Los Angeles, IGPP, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, ESS, Los Angeles, CA 90095 USA. IFSI, I-00133 Rome, Italy. MP Ae, Katlenburg Lindau, Germany. IAFS, I-00133 Rome, Italy. LANL, Los Alamos, NM 87545 USA. DLR, D-12489 Berlin, Germany. JPL, Pasadena, CA 91109 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Tennessee, Knoxville, TN 37996 USA. Free Univ Berlin, D-12249 Berlin, Germany. Brown Univ, Providence, RI 02912 USA. GSFC, Greenbelt, MD 20771 USA. Univ Arizona, Tucson, AZ 85721 USA. New Rds Sch, Santa Monica, CA 90404 USA. MIT, Cambridge, MA 02139 USA. RP Russell, CT (reprint author), Univ Calif Los Angeles, IGPP, 3845 Slichter Hall,MS 156704, Los Angeles, CA 90095 USA. EM ctrussell@igpp.ucla.edu RI McFadden, Lucy-Ann/I-4902-2013; De Sanctis, Maria Cristina/G-5232-2013; OI McFadden, Lucy-Ann/0000-0002-0537-9975; De Sanctis, Maria Cristina/0000-0002-3463-4437; Prettyman, Thomas/0000-0003-0072-2831; Russell, Christopher/0000-0003-1639-8298 NR 93 TC 66 Z9 67 U1 0 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR-MAY PY 2004 VL 52 IS 5-6 BP 465 EP 489 DI 10.1016/j.pss.2003.06.013 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807CJ UT WOS:000220479300012 ER PT J AU Lamar, JE Cronin, CK Scott, LE AF Lamar, JE Cronin, CK Scott, LE TI A review of steps taken to create an international virtual laboratory at NASA Langley for aerodynamic prediction and comparison SO PROGRESS IN AEROSPACE SCIENCES LA English DT Review ID COMPUTATIONAL FLUID-DYNAMICS AB A review of the steps taken to establish an international virtual laboratory (VL) at the NASA Langley Research Center for aerodynamic prediction and comparison of flight data in the post-09/11/2001 cyber-terrorist environment is detailed here. The key features of the VL include an intuitive, web-based user interface for ease of access, a secure highspeed Internet connection between browser and server, a relational database architecture for data and information search, and a secure file-storage system. The detailed planning and handling of such issues as security, computer firewall access and legal protection of data are provided. Published by Elsevier Ltd. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. NCI, ConITS Contract, Hampton, VA 23666 USA. RP Lamar, JE (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. EM j.e.lamar@nasa.gov NR 29 TC 6 Z9 7 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0376-0421 J9 PROG AEROSP SCI JI Prog. Aeosp. Sci. PD APR PY 2004 VL 40 IS 3 BP 163 EP 172 DI 10.1016/j.paerosci.2004.03.002 PG 10 WC Engineering, Aerospace SC Engineering GA 830NQ UT WOS:000222129600003 ER PT J AU Vacca, WD Cushing, MC Rayner, JT AF Vacca, WD Cushing, MC Rayner, JT TI Nonlinearity corrections and statistical uncertainties associated with near-infrared arrays SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID SPECTROGRAPH; TELESCOPE; PERFORMANCE; HGCDTE AB We derive general equations for nonlinearity corrections and statistical uncertainty (variance) estimates for data acquired with near-infrared detectors employing correlated double sampling, multiple correlated double sampling (Fowler sampling), and uniformly spaced continuous readout techniques. We compare our equation for the variance on each pixel associated with Fowler sampling with data taken with the array installed in the near-infrared cross-dispersed spectrograph (SpeX) at the NASA Infrared Telescope Facility and find that it provides an accurate representation of the empirical results. This comparison also reveals that the read noise associated with a single readout of the SpeX array increases with the number of nondestructive reads, n(r), as n(r)(0.16). This implies that the effective read noise of a stored image decreases as n(r)(-0.34), shallower than the expected rate of n(r)(-0.5). The cause of this read noise behavior is uncertain but it may be due to heating of the array as a result of the multiple readouts. Such behavior may be generic to arrays that employ correlated or multiple correlated double sampling readouts. C1 NASA, SOFIA USRA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. RP Vacca, WD (reprint author), NASA, SOFIA USRA, Ames Res Ctr, MS 144-2, Moffett Field, CA 94035 USA. EM wvacca@mail.arc.nasa.gov; cushing@ifa.hawaii.edu; rayner@ifa.hawaii.edu NR 15 TC 32 Z9 32 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD APR PY 2004 VL 116 IS 818 BP 352 EP 361 DI 10.1086/382906 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 810WZ UT WOS:000220735700007 ER PT J AU Cushing, MC Vacca, WD Rayner, JT AF Cushing, MC Vacca, WD Rayner, JT TI Spextool: A spectral extraction package for SpeX, a 0.8-5.5 micron cross-dispersed spectrograph SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID ALGORITHM; PHOTOMETRY; REDUCTION AB We describe an IDL-based package for the reduction of spectral data obtained with SpeX, a medium-resolution, 0.8-5.5 mum cross-dispersed spectrograph and imager for the NASA Infrared Telescope Facility. The package, called Spextool, carries out all the procedures necessary to produce fully reduced spectra including preparation of calibration frames, processing and extraction of spectra from science frames, wavelength calibration of spectra, and flux calibration of spectra. The package incorporates an "optimal extraction" algorithm for point-source data and also generates realistic error arrays associated with the extracted spectra. Because it is fairly quick and easy to use, requiring minimal user interaction, Spextool can be run by observers at the telescope to estimate the signal-to-noise ratio of their data. We describe the procedures incorporated into Spextool and show examples of extracted spectra. C1 NASA, SETI Inst, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Cushing, MC (reprint author), NASA, SETI Inst, Ames Res Ctr, MS 245-3, Moffett Field, CA 94035 USA. EM mcushing@arc.nasa.gov; wvacca@mail.arc.nasa.gov; rayner@irtf.hawaii.edu NR 16 TC 519 Z9 519 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD APR PY 2004 VL 116 IS 818 BP 362 EP 376 DI 10.1086/382907 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 810WZ UT WOS:000220735700008 ER PT J AU Errico, RM Raeder, K Ehrendorfer, M AF Errico, RM Raeder, K Ehrendorfer, M TI Singular vectors for moisture-measuring norms SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE adjoint models; data assimilation; precipitation forecasting; predictability ID PRIMITIVE-EQUATION MODEL; OPTIMAL PERTURBATIONS; DATA ASSIMILATION; PREDICTION MODEL; PHYSICS; GROWTH; CONSTRUCTION; CIRCULATION; SENSITIVITY; ADJOINT AB Singular vectors (SVs) are determined for 12-hour forecasts Using a regional mesoscale model. Norms used as constraints at the initial time include the usual total-energy norm, a related moisture-measuring norm, and norms Using weights equal to the inverse of estimated variances of initial-condition Uncertainty. NormS Used to measure perturbations at the end of the forecast include either the total energy or mean-squared perturbed rate of precipitation. Four Synoptic Cases are examined. The locations of the four leading SVs for each pair of norms considered differ widely for some cases but are collocated for others. The initial vertical structures of the SVs are also sensitive to norms and cases. Most importantly. both final-time norms are sensitive to initial perturbations of both moisture and dynamic fields. For some cases. similar structures are optimal for maximizing both perturbation energy and precipitation. When the initial moisture SVs are introduced in the nonlinear forecast model with perturbation magnitudes of the size of initial-condition uncertainties, many of the results remarkably match corresponding tangent-linear estimates. In other nonlinear experiments. however, the matches are poor in terms of either correlation or magnitude measures, or both, indicating that the tangent-linear results are sometimes informative but at other times can be misleading. For the present study the key reported tangent-linear model results were, therefore, all confirmed in the nonlinear context, An implication of the results is that as much attention must be paid to moisture analysis as to analysis of other fields, and that ensemble forecast techniques should consider initial moisture uncertainty. C1 NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. Natl Ctr Atmospher Res, Boulder, CO USA. Univ Innsbruck, A-6020 Innsbruck, Austria. RP Errico, RM (reprint author), NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Code 900-3, Greenbelt, MD 20771 USA. EM rerrico@gmao.gsfc.nasa.gov NR 36 TC 12 Z9 12 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-9009 J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD APR PY 2004 VL 130 IS 598 BP 963 EP 987 DI 10.1256/qj.02.227 PN A PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 819DA UT WOS:000221292200011 ER PT J AU Osborne, SR Haywood, JM Francis, PN Dubovik, O AF Osborne, SR Haywood, JM Francis, PN Dubovik, O TI Short-wave radiative effects of biomass burning aerosol during SAFARI2000 SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE aerosol optical depth; aircraft measurements; downwelling sky radiances; flexible radiation code; upwelling irradiances ID OPTICAL-PROPERTIES; AIRCRAFT OBSERVATIONS; SMOKE PARTICLES; C-130 AIRCRAFT; DISTRIBUTIONS; ABSORPTION; RETRIEVAL; AFRICA; CLOUD; SUN AB We present data from two case-studies during the Southern AFricAn Research Initiative (SAFARI2000) of the radiative effects of a biomass burning plume advecting over the ocean. In situ aircraft measurements were made of the aerosol vertical structure, the aerosol microphysics, and the aerosol optical properties (scattering and absorption coefficients). Remote sensing measurements of the upwelling broadband short-wave (SW) radiative fluxes (0.3-3.0 mum) were made above the plume. Together with modelling of the clear-air flux using a flexible radiation scheme, we have been able to determine the local mean direct radiative effects of the aerosol column for the two cases. Aerosol optical depths were derived using a number of techniques: the upwelling fluxes, vertical integration of the in situ extinction coefficient, and using downwelling sky radiances. These optical depths are compared and discussed; discrepancies are revealed through instrument sampling problems and horizontal inhomogeneity of the aerosol. Spectrally resolved downwelling SW sky radiances as a function of scattering angle were measured and modelled. The modelling technique illustrates the importance of including unpolluted marine boundary-layer aerosol as part of the aerosol column. A retrieval algorithm that uses the measured downwelling sky radiances as input has also been utilized. This algorithm derives a columnar aerosol size distribution for comparison against the measured biomass burning and marine boundary-layer size distributions. The retrieved columnar size distribution is acceptable in representing the atmospheric aerosol in terms of describing the effect on scattered radiances. C1 Met Off, Exeter EX1 3PB, Devon, England. NASA, Goddard Space Flight Ctr, Terr Phys Lab, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. RP Osborne, SR (reprint author), Met Off, FitzRoy Rd, Exeter EX1 3PB, Devon, England. EM simon.osborne@metoffice.com RI Dubovik, Oleg/A-8235-2009; Francis, Peter/H-9352-2013 OI Dubovik, Oleg/0000-0003-3482-6460; Francis, Peter/0000-0002-5869-803X NR 30 TC 14 Z9 16 U1 1 U2 2 PU ROYAL METEOROLOGICAL SOC PI READING PA 104 OXFORD ROAD, READING RG1 7LJ, BERKS, ENGLAND SN 0035-9009 J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD APR PY 2004 VL 130 IS 599 BP 1423 EP 1447 DI 10.1256/qj.03.134 PN B PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 832XF UT WOS:000222300300013 ER PT J AU Joiner, J Poli, P Frank, D Liu, HC AF Joiner, J Poli, P Frank, D Liu, HC TI Detection of cloud-affected AIRS channels using an adjacent-pixel approach SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE assimilation; high resolution; radiances ID NUMERICAL WEATHER PREDICTION; INFORMATION-CONTENT; DATA ASSIMILATION; ANALYSIS SYSTEM; CLEAR-SKY; RADIANCES; ATMOSPHERES; MODEL AB High-spectral-resolution infrared sounders such as the Atmospheric InfraRed Sounder (AIRS), flying on the National Aeronautics and Space Administration Earth Observing System (EOS) Aqua satellite, provide information about vertical temperature and humidity structure that is potentially useful for data assimilation and numerical weather prediction. Tropospheric channels from infrared sounders are frequently affected by cloud. The methods currently used operationally to account for cloud effects are screening to eliminate cloud-contaminated data and cloud-clearing. For either approach, it is important to determine which channels peak sufficiently above the cloud so that they are not contaminated. Depending on the sounding, different combinations of channels are cloud-contaminated, thus making cloud detection difficult. This paper proposes a new method of identifying clear or unaffected channels using adjacent pixels. Unlike other proposed or implemented methods, this approach does not rely heavily on having accurate background information about the atmospheric state or estimates of its error. The method also does not make any assumptions about cloud spectral properties. Instead, it assumes that clouds will produce adjacent-pixel variability. The approach requires an estimate of clear-scene adjacent-pixel homogeneity that can be obtained with real data. We apply the methodology to simulated AIRS data using Monte Carlo experiments. We then apply the algorithm to real AIRS data and use brightness temperature departure statistics as an independent check for residual cloud contamination. We also make qualitative comparisons with cloud properties derived from the EOS Aqua Moderate-Resolution Imaging Spectroradiometer instrument. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Maryland, College Pk, MD 20742 USA. Meteo France, Ctr Natl Rech Meteorol, Toulouse, France. Sci Applicat Int Corp, Mclean, VA 22102 USA. RP Joiner, J (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. EM joiner@gmao.gsfc.nasa.gov RI Joiner, Joanna/D-6264-2012; OI Poli, Paul/0000-0002-8392-6524 NR 23 TC 7 Z9 7 U1 0 U2 1 PU ROYAL METEOROLOGICAL SOC PI READING PA 104 OXFORD ROAD, READING RG1 7LJ, BERKS, ENGLAND SN 0035-9009 J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD APR PY 2004 VL 130 IS 599 BP 1469 EP 1487 DI 10.1256/qj.03.93 PN B PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 832XF UT WOS:000222300300015 ER PT J AU Foster, JE AF Foster, JE TI Observation of dust stream formation produced by low current, high voltage cathode spots SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID PLASMAS AB Macroparticle acceleration driven by low current, high voltage cathode spots has been investigated for potential applications ranging from micrometeoroid simulation to nanoparticle deposition/implantation. Acceleration by this process was observed to occur when nanometer and micrometer-sized particles were exposed to a high voltage pulse in the presence of a plasma discharge. The applied negative voltage pulse initiates the formation of multiple, high voltage, low current cathode spots which provide the mechanism of actual acceleration of the charged dust particles. Dust streams generated by this process were detected using laser scattering techniques. Cathode spot behavior was also documented. The particle impact craters observed at the surface of downstream witness badges were documented using scanning electron microscopy and light microscopy. The observed impacts suggest the presence of energetic macroparticles formed during this process. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Foster, JE (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM john.foster@grc.nasa.gov NR 25 TC 3 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD APR PY 2004 VL 75 IS 4 BP 947 EP 954 DI 10.1063/1.1688441 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 805CI UT WOS:000220344000022 ER PT J AU Stoica, A AF Stoica, A TI Special issue on evolvable hardware SO SOFT COMPUTING LA English DT Editorial Material C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Stoica, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Adrian-Stoica@jpl.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1432-7643 J9 SOFT COMPUT JI Soft Comput. PD APR PY 2004 VL 8 IS 5 BP 305 EP 306 DI 10.1007/s00500-003-0286-y PG 2 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Computer Science GA 828WB UT WOS:000222003300001 ER PT J AU Shibata, H Stoica, A Fujii, N AF Shibata, H Stoica, A Fujii, N TI Controllable decoding for automated analog circuit structure design SO SOFT COMPUTING LA English DT Article DE analog circuit; automated circuit synthesis; genetic algorithm ID EVOLUTION AB The decoding scheme is a major problem in automated analog circuit topology synthesis since decoding schemes bias synthesized circuit structures. However, the proper decoding scheme varies depending on the method to realize a given function. In this paper, a controllable decoding scheme is proposed in which the method to realize a function is controlled by a set of 11 prototype circuits". Thus, the system can generate different types of analog circuits in a unified method. The prototype circuits are designed by a human and suggested to the system as hints of configurations of new analog circuits to be synthesized by the system. In the synthesis process, the information on circuit connections is stored as sub-circuits extracted from the prototype circuits. A genetic algorithm is then used to search for art optimum combination of the sub-circuits that achieves the desired electronic specifications. The combinations of sub-circuits are generated with a proposed technique where the terminals of the sub-circuits are shared. The capabilities of the proposed method are demonstrated through synthesis examples of a cubing circuit synthesis as a current-mode design and a logic circuit synthesis as a voltage-mode. C1 Analog Devices Inc, Minato Ku, Tokyo 1056891, Japan. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Tokyo Inst Technol, Dept Phys Elect, Meguro Ku, Tokyo 1528552, Japan. RP Shibata, H (reprint author), Analog Devices Inc, Minato Ku, 16-1-1 Kaigan, Tokyo 1056891, Japan. EM Hajime.Shibata@analog.com NR 10 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1432-7643 J9 SOFT COMPUT JI Soft Comput. PD APR PY 2004 VL 8 IS 5 BP 344 EP 353 DI 10.1007/s00500-003-0291-1 PG 10 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Computer Science GA 828WB UT WOS:000222003300006 ER PT J AU Stoica, A Zebulum, RS Keymeulen, D Ferguson, MI Duong, V Guo, X AF Stoica, A Zebulum, RS Keymeulen, D Ferguson, MI Duong, V Guo, X TI Evolvable hardware techniques for on-chip automated reconfiguration of programmable devices SO SOFT COMPUTING LA English DT Article DE automated design; evolvable hardware; genetic algorithms; reconfigurable chips; programmable devices ID TRANSISTOR ARRAYS; EVOLUTION AB While complete automated design is a harder problem than computer-assisted design, automated hardware reconfiguration is an even more challenging problem, because it needs to adjust to limited resources and various factors, such as noise and parasitic capacitance, a resistance and inductance. This paper presents some experimental results of on-chip automated design and reconfiguration using evolvable hardware techniques. It describes a stand-alone board level evolvable system, and its use to demonstrate on-chip synthesis of new circuits in only a few seconds. The experiments presented here indicate a recovery capability in the case of extreme environmental conditions, such as extreme temperatures, that adversely affect electronics. Some of the difficulties of dealing with the real hardware are exposed, as well as challenges more generally related to automated evolution of complex electronic systems. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Chromatech, Alameda, CA 94501 USA. RP Stoica, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM adrian.stoica@jpl.nasa.gov NR 21 TC 7 Z9 7 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1432-7643 J9 SOFT COMPUT JI Soft Comput. PD APR PY 2004 VL 8 IS 5 BP 354 EP 365 DI 10.1007/s00500-003-0292-0 PG 12 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Computer Science GA 828WB UT WOS:000222003300007 ER PT J AU Richardson, IG AF Richardson, IG TI Energetic particles and corotating interaction regions in the solar wind SO SPACE SCIENCE REVIEWS LA English DT Review DE Corotating interaction regions; cosmic rays; energetic particles; interplanetary magnetic field; solar wind ID GALACTIC COSMIC-RAYS; LARGE HELIOCENTRIC DISTANCES; HELIOSPHERIC CURRENT SHEET; HIGH-LATITUDE HELIOSPHERE; INTERPLANETARY MAGNETIC FIELD; ION COMPOSITION SPECTROMETER; ROTATING INTERACTION REGIONS; QUIET-TIME SPECTRA; SOURCE PICKUP IONS; EARTHS BOW SHOCK AB This paper reviews three important effects on energetic particles of corotating interaction regions (CIRs) in the solar wind that are formed at the leading edges of high-speed solar wind streams originating in coronal holes. A brief overview of CIRs and their important features is followed by a discussion of CIR-associated modulations in the galactic cosmic ray intensity, with an emphasis on observations made by spacecraft particle telescope 'anti-coincidence' guards. Such guards combine high counting rates (hundreds of counts/s) and a lower rigidity response than neutron monitors to provide detailed information on the relationship between cosmic ray modulations and CIR structure. The modulation of Jovian electrons by CIRs is then described. Finally, the acceleration of ions to energies of similar to 20 MeV/n in the vicinity of CIRs is reviewed. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Richardson, IG (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. OI Richardson, Ian/0000-0002-3855-3634 NR 293 TC 84 Z9 84 U1 2 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD APR PY 2004 VL 111 IS 3-4 BP 267 EP 376 DI 10.1023/B:SPAC.0000032689.52830.3e PG 110 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 831ZB UT WOS:000222234400001 ER PT J AU Kincaid, RK Griffith, MM Sykes, R Sobieszczanski-Sobieski, J AF Kincaid, RK Griffith, MM Sykes, R Sobieszczanski-Sobieski, J TI Bell-curve genetic algorithm for mixed continuous and discrete optimization problems SO STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION LA English DT Article DE genetic algorithms; evolutionary search; heuristics; discrete and continuous optimization AB We continue our study of a variant of the Genetic Algorithm in which the reproduction mechanism is modified to base it on the Gaussian probability distribution, the bell curve. In this manuscript we examine an extension of the bell-curve based (BCB) heuristic procedure for a mix of continuous and quasi-discrete, as well as truly-discrete applications. We begin by testing two refinements to the discrete version of BCB. We compare the performance of midpoint versus fitness based selection. In addition we test the performance of discrete normal tails versus standard mutation and demonstrate that the discrete normal tails are better. Lastly, we implement these refinements in a combined continuous and discrete BCB and compared the performance of two discrete distance measures on a hub design problem. Here we found that when order-does-matter it pays to take it into account. C1 Coll William & Mary, Dept Math, Williamsburg, VA 23187 USA. Coll William & Mary, Dept Comp Sci, Williamsburg, VA 23187 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Kincaid, RK (reprint author), Coll William & Mary, Dept Math, Williamsburg, VA 23187 USA. EM rrkinc@math.wm.edu; shelley@pisymbol.com; resykes@cs.wm.edu; j.sobieski@larc.nasa.gov NR 16 TC 0 Z9 0 U1 1 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1615-147X EI 1615-1488 J9 STRUCT MULTIDISCIP O JI Struct. Multidiscip. Optim. PD APR PY 2004 VL 26 IS 6 BP 396 EP 405 DI 10.1007/s00158-003-0358-8 PG 10 WC Computer Science, Interdisciplinary Applications; Engineering, Multidisciplinary; Mechanics SC Computer Science; Engineering; Mechanics GA 810OQ UT WOS:000220714000002 ER PT J AU Canzian, A Mosca, HO Bozzolo, G AF Canzian, A Mosca, HO Bozzolo, G TI Atomistic modeling of Pt deposition on Cu(111) and Cu deposition on Pt(111) SO SURFACE REVIEW AND LETTERS LA English DT Article DE adatoms; computer simulations; copper; platinum; semiempirical methods and model calculations; surface alloys; surface structure ID SURFACE ALLOY; GROWTH; FILMS; PHOTOEMISSION; SEGREGATION; PT/CU(111); ADSORPTION AB A modeling analysis of the growth mode of submonolayer amounts of Pt on Cu(111) and Cu on Pt(111) for different coverages and temperatures reproduces the known experimental behavior. An atom-by-atom analysis of the energetics using the BFS method for alloys provides a simple explanation of the underlying mechanisms leading to the observed behavior. C1 NASA Glenn Res Ctr, Cleveland, OH 44135 USA. Ohio Aerosp Inst, Cleveland, OH 44142 USA. UAM, Comis Nacl Energia Atom, San Martin, Argentina. Univ Tecnol Nacl, Fac Reg Gral Pacheco, Pacheco, Argentina. RP Bozzolo, G (reprint author), NASA Glenn Res Ctr, MS 23-2, Cleveland, OH 44135 USA. EM Guillermo.H.Bozzolo@grc.nasa.gov NR 14 TC 5 Z9 5 U1 0 U2 7 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-625X J9 SURF REV LETT JI Surf. Rev. Lett. PD APR PY 2004 VL 11 IS 2 BP 235 EP 243 DI 10.1142/S0218625X04006116 PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 829VU UT WOS:000222079300015 ER PT J AU Le Pivert, P Haddad, RS Aller, A Titus, K Doulat, J Renard, M Morrison, DR AF Le Pivert, P Haddad, RS Aller, A Titus, K Doulat, J Renard, M Morrison, DR TI Ultrasound guided combined cryoablation and microencapsulated 5-fluorouracil inhibits growth of human prostate tumors in xenogenic mouse model assessed by luminescence imaging SO TECHNOLOGY IN CANCER RESEARCH & TREATMENT LA English DT Article DE microencapsulated chemotherapy; cryochemotherapy; cryosurgery; 5-FU; ultrasound; bioluminescence; prostate tumor ID LIPOSOMAL DOXORUBICIN ACCUMULATION; IN-VIVO; RADIOFREQUENCY ABLATION; CANCER; CRYOSURGERY; TISSUE; CRYOCHEMOTHERAPY; CHEMOTHERAPY AB Modern approaches to minimally invasive ablative treatment of solid tumors involve the use of miniature instruments and combined treatments. These can be enhanced with ultrasound imaging that depicts tumor margins; facilitates guidance, delivery, and dosage of local chemotherapy; and can monitor the effectiveness of the treatment. This paper describes the advantages of ultrasound guided cryosurgery combined with local chemotherapy delivered in multilamellar, echogenic microcapsules of 5-FU ("mucaps") using a xenograft tumor model. Genetically engineered bioluminescent human prostate tumor cells, DU-145(Luc+), were implanted subcutaneously into athymic nude mice. Experiments were designed to mimic the situation where palliative cryoablation spares a portion of the tumor so that the combined effect of cryosurgery and focal injections of chemotherapeutic microcapsules could be evaluated. Eighteen (18) tumors were treated with percutaneous partial cryoablation or interstitial chemoablation, or a combination of both. A single F/T cycle was applied to tumor and micro-encapsulated chemotherapy is delivered at outer margin of frozen tumor in two opposite sites. Results show that the tumor and cryosurgical kill zone contours were seen with both the bio-luminescence assay (BLI) and ultrasonography (US). US can easily detect as little as 2 mul of echogenic pcaps, and monitor their lifetime in the tumor tissue. BLI was determinant in showing that minute amounts of microcapsule chemotherapy (38.7 ng of 5-FU/g tumor) dramatically inhibited tumor growth starting within two days after injection. The mean BLI emitted by control tumors was 5.6 times greater at Day 4 than the BLI measurements from tumors treated with 5-FU mucaps (p=0.036). By Day 7, BLI values from the control tumors were still 2.7 times greater than those treated with 5-FU mucaps (p<0.01). In tumors treated by partial cryoablation, the mean BLI of viable tumor cells was 20 times less at day 3 (p=0.05) and 46% less at day 7 than the non-treated tumors. The combined treatment produced a dramatic inhibition of tumor growth that lasted throughout the 7-day study. The BLI measured from viable tumor cells in non-treated tumors was 34 times greater at day 3 and more than 350 times greater at day 7 than those treated by combined cryoablation and 5-FU mucaps. The results demonstrated, for the first time, that a single moderate freeze of a human prostate tumor combined with bi-focal peripheral microcapsule chemotherapy (5-FU) has a better and longer inhibitory effect on tumor growth compared to the growth inhibition rendered by cryosurgery or local microcapsule chemo-therapy alone. This shows promise for a new, focal, combined ablative modality using US guided deposition of microencapsulated drug(s) and echogenic markers deposited in the hypothermic margin of tumors which could enhance the efficacy of cryoablation of prostate cancers. C1 Crit Care Innovat, Chantilly, VA 20151 USA. NASA, Johnson Space Ctr, Biol Syst Off, Houston, TX 77508 USA. Rumbaugh Goodwin Inst Canc Res, Plantation, FL 33313 USA. SODELOG, F-38330 Montbonnot St Martin, France. RP Le Pivert, P (reprint author), Crit Care Innovat, 13901 Willard Rd, Chantilly, VA 20151 USA. EM plepivert@earthlink.net NR 37 TC 20 Z9 20 U1 0 U2 3 PU ADENINE PRESS PI SCHENECTADY PA 2066 CENTRAL AVE, SCHENECTADY, NY 12304 USA SN 1533-0346 J9 TECHNOL CANCER RES T JI Technol. Cancer Res. Treat. PD APR PY 2004 VL 3 IS 2 BP 135 EP 142 PG 8 WC Oncology SC Oncology GA 816MR UT WOS:000221114500006 PM 15059019 ER PT J AU Chamis, CC AF Chamis, CC TI Probabilistic simulation of multi-scale composite behavior SO THEORETICAL AND APPLIED FRACTURE MECHANICS LA English DT Article AB A methodology is developed to computationally assess the probabilistic composite behavior at all composite scales (from micro to structural) due to the uncertainties in the constituent (fiber and matrix) properties, in the fabrication process and in structural variables (primitive variables). The methodology is computationally efficient for simulating the probability distributions of composite behavior, such as material properties, laminate and structural responses. Byproducts of the methodology are probabilistic sensitivities of the composite primitive variables. The methodology has been implemented into the computer codes: Probabilistic Integrated Composite ANalyzer (PICAN) and Integrated Probabilistic Assessment of Composite Structures (IPACS). The accuracy and efficiency of this methodology are demonstrated by simulating the uncertainties in composite typical laminates and comparing the results with the Monte Carlo simulation method. Available experimental data of composite laminate behavior at all scales fall within the scatters predicted by PICAN. Multi-scaling is extended to simulate probabilistic thermo-mechanical fatigue and to simulate the probabilistic design of a composite redome in order to illustrate its versatility. Results show that probabilistic fatigue can be simulated for different temperature amplitudes and for different cyclic stress magnitudes. Results also show that laminate configurations can be selected to increase the redome reliability by several orders of magnitude without increasing the laminate thickness-a unique feature of structural composites. (C) 2003 Elsevier Ltd. All rights reserved. C1 NASA, Glenn Res Ctr, Res & Technol Directorate, Cleveland, OH 44135 USA. RP Chamis, CC (reprint author), NASA, Glenn Res Ctr, Res & Technol Directorate, 21000 Brook Pk Rd, Cleveland, OH 44135 USA. EM cchamis@lerc.nasa.gov NR 9 TC 29 Z9 34 U1 1 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8442 J9 THEOR APPL FRACT MEC JI Theor. Appl. Fract. Mech. PD APR PY 2004 VL 41 IS 1-3 BP 51 EP 61 DI 10.1016/j.tafmec.2003.11.005 PG 11 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 811CN UT WOS:000220750100007 ER PT J AU Arkin, CR Griffin, TP Diaz, JA Follistein, DW Curley, CH Floyd, DP Naylor, GR Haskell, WD Blalock, M Adams, FW AF Arkin, CR Griffin, TP Diaz, JA Follistein, DW Curley, CH Floyd, DP Naylor, GR Haskell, WD Blalock, M Adams, FW TI A small mass spectrometer system for in situ gas analysis SO TRAC-TRENDS IN ANALYTICAL CHEMISTRY LA English DT Article AB Kennedy Space Center (KSC) has developed a portable mass spectrometer (MS) system that is capable of flight from sea level to 44,000 feet (13.4 km), totally autonomous and capable of monitoring permanent gases as well as organics up to 200 Thompson (Th equivalent to amu/e). This article presents information about the system. (C) 2004 Published by Elsevier B.V. C1 ASCR Aerosp Corp, Kennedy Space Ctr, FL 32899 USA. NASA, Kennedy Space Ctr, FL 32899 USA. Univ Costa Rica, Escuela Fis, San Jose, Costa Rica. RP Arkin, CR (reprint author), ASCR Aerosp Corp, ASRC-14, Kennedy Space Ctr, FL 32899 USA. EM richard.arkin-1@ksc.nasa.gov NR 9 TC 10 Z9 10 U1 0 U2 3 PU ELSEVIER SCIENCE LONDON PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0165-9936 J9 TRAC-TREND ANAL CHEM JI Trac-Trends Anal. Chem. PD APR PY 2004 VL 23 IS 4 BP 322 EP 330 PG 9 WC Chemistry, Analytical SC Chemistry GA 834KD UT WOS:000222409100030 ER PT J AU DellaCorte, C AF DellaCorte, C TI News flash! Oil is out! Oil-free is in! SO TRIBOLOGY & LUBRICATION TECHNOLOGY LA English DT Editorial Material C1 NASA, Glenn Res Ctr, Cleveland, OH USA. RP DellaCorte, C (reprint author), NASA, Glenn Res Ctr, Cleveland, OH USA. EM cdellacorte@stle.org NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC TRIBOLOGISTS & LUBRICATION ENGINEERS PI PARK RIDGE PA 840 BUSSE HIGHWAY, PARK RIDGE, IL 60068 USA SN 0024-7154 J9 TRIBOL LUBR TECHNOL JI Tribol. Lubr. Technol. PD APR PY 2004 VL 60 IS 4 BP 6 EP 6 PG 1 WC Engineering, Mechanical SC Engineering GA 804VG UT WOS:000220325600002 ER PT J AU Vlcek, BL Hendricks, RC Zaretsky, EV AF Vlcek, BL Hendricks, RC Zaretsky, EV TI Monte Carlo simulation of sudden death bearing testing SO TRIBOLOGY TRANSACTIONS LA English DT Article; Proceedings Paper CT STLE/ASME Tribology Conference CY OCT 26-29, 2003 CL PONTE VEDRA, FL SP STLE, ASME DE rolling-element bearings; life prediction; Weibull analysis; sudden death testing; computer simulation; Monte Carlo analysis ID FATIGUE LIFE AB Monte Carlo simulations combined with sudden death testing were used to compare resultant bearing lives to the calculated bearing life and the cumulative test time and calendar time relative to sequential and censored sequential testing. A total of 30,960 virtual 50-mm bore deep-groove ball bearings were evaluated in 33 different sudden death test configurations comprising 36, 72, and 144 bearings each. Variations in both life and Weibull slope were a function of the number of bearings failed independent of the test method used and not the total number of bearings tested. Variations in L-10 life as a function of number of bearings failed were similar to variations in life obtained from sequentially failed real bearings and from Monte Carlo (virtual) testing of entire populations. Reductions up to 40% in bearing test time and calendar time can be achieved by testing to failure or the L-50 life and terminating all testing when the last of the predetermined bearing failures has occurred. Sudden death testing is not a more efficient method to reduce bearing test time or calendar time when compared to censored sequential testing. C1 Georgia So Univ, Statesboro, GA 30460 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Vlcek, BL (reprint author), Georgia So Univ, Statesboro, GA 30460 USA. NR 18 TC 4 Z9 4 U1 0 U2 2 PU SOC TRIBOLOGISTS & LUBRICATION ENGINEERS PI PARK RIDGE PA 840 BUSSE HIGHWAY, PARK RIDGE, IL 60068 USA SN 1040-2004 J9 TRIBOL T JI Tribol. Trans. PD APR-JUN PY 2004 VL 47 IS 2 BP 188 EP 199 DI 10.1080/05698190490431867 PG 12 WC Engineering, Mechanical SC Engineering GA 820FQ UT WOS:000221373200003 ER PT J AU Treuhaft, RN Siqueira, PR AF Treuhaft, RN Siqueira, PR TI The calculated performance of forest structure and biomass estimates from interferometric radar SO WAVES IN RANDOM MEDIA LA English DT Article ID TOPOGRAPHY; FUSION; LIDAR AB Vertical structure and biomass are key characteristics of the forest random medium. This paper calculates the power and interferometric synthetic aperture radar (InSAR) sensitivity to tree height and vegetation density as it manifests in extinction, using a homogeneous, random-volume model of the forest medium, and accounting for speckle and thermal noise. Tree height and extinction are both related to biomass within the context of this simple model. Signal and noise calculations show that InSAR coherence and phase are more sensitive than radar power to structure and biomass to 10% variations in structure parameters over a wide range of medium to high density forests. For example, for extinctions of 0.2 db m(-1) and other parameters as noted in the text, the sensitivity of InSAR coherence to 10% changes in tree height exceeds observation errors for trees shorter than about 37 m, as opposed to 14 m for radar power. InSAR phase sensitivity to 10% structural and associated biomass changes exceeds observation errors for all tree heights. Only for the very lowest densities, for extinctions less than 0.15 db m(-1), does radar power sensitivity to density exceed that of InSAR; even at low densities, InSAR sensitivity to tree height outperforms that of radar power in these calculations. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Treuhaft, RN (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 138-212, Pasadena, CA 91109 USA. EM Robert.Treuhaft@jpl.nasa.gov; Paul.Siqueira@jpl.nasa.gov RI Siqueira, Paul/D-9760-2016 OI Siqueira, Paul/0000-0001-5781-8282 NR 20 TC 18 Z9 18 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0959-7174 J9 WAVE RANDOM MEDIA JI Waves Random Media PD APR PY 2004 VL 14 IS 2 BP S345 EP S358 AR PII S0959-7174(04)70429-2 DI 10.1088/0959-7174/14/2/013 PG 14 WC Physics, Multidisciplinary SC Physics GA 817OD UT WOS:000221185900014 ER PT J AU Chernov, AA AF Chernov, AA TI Notes on interface growth kinetics 50 years after Burton, Cabrera and Frank SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT Symposium on 50 Years of Progress in Crystal Growth CY AUG 04-09, 2002 CL Seattle, WA SP Amer Assoc Crystal Growth DE fluid flows; growth models; impurities; morphological stability; surface processes ID PHASE-SHIFTING INTERFEROMETRY; CRYSTAL-GROWTH; MORPHOLOGICAL STABILITY; VICINAL FACE; LYSOZYME CRYSTALS; STEP VELOCITY; FREE-ENERGY; FLOW; SURFACES; LIQUID AB This overview is devoted to some unresolved basic problems in crystal growth kinetics. The density wave approach to propagation of a spatially diffuse interface between a growing crystal and its simple (e.g., metallic) melt is discussed in Section 2. This approach allows for the calculation of kinetic coefficients and is an alternative to the localized interface concept in which each atom belongs to either a solid or a liquid. Sections 3 and 4 deal mainly with layer growth from solution. Mutual retardation of the growth steps via their bulk and surface diffusion fields is the major subject. The influence of solution flow on step bunching (Section 4) suggests the essential influence of bulk diffusion on the surface morphology. The flow within the solution boundary layer enhances step-step interaction, influences the step bunching process and the resulting step pattern morphology on the growing surface. Recent experiments on the rates at which strongly polygonized steps on protein and small molecule crystals propagate during growth from solution are analyzed in Section 5. We have shown that the step segments may be "singular" and that "one-dimensional nucleation" may be the rate limiting stage for the segments that are shorter or comparable in length to the thermodynamic equilibrium interkink distance. In this case, the reciprocal dependence of the segment propagation rate on the segment length that follow from the Gibbs-Thomson law, should be replaced by an abrupt switch from zero to a finite constant velocity. Until recently, the Kossel crystal remained the only model used in crystal growth theory. In such Kossel crystals, all kinks at the steps are identical and the kink rate is a linear function of the supersaturation. In the non-Kossel crystals, there may be several kink configurations characterized by different geometries and energies. These configurations should appear in a specific sequence when each new lattice unit cell is filled. As a result of such a cooperative interaction within the unit cell, a non-linear dependence of the kink rate on the vapor pressure or solution concentration in excess over the equilibrium value should be expected. (C) 2004 Elsevier B.V. All rights reserved. C1 NASA, George C Marshall Space Flight Ctr, BAE Syst N Amer, Huntsville, AL 35812 USA. RP Chernov, AA (reprint author), NASA, George C Marshall Space Flight Ctr, BAE Syst N Amer, Mail Code SD46, Huntsville, AL 35812 USA. EM alex.chernov@msfc.nasa.gov NR 85 TC 86 Z9 89 U1 6 U2 36 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR 31 PY 2004 VL 264 IS 4 BP 499 EP 518 DI 10.1016/j.jcrysgro.2003.12.076 PG 20 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 809QO UT WOS:000220651400003 ER PT J AU Wang, CA Carlson, D Motakef, S Wiegel, M Wargo, MJ AF Wang, CA Carlson, D Motakef, S Wiegel, M Wargo, MJ TI Research on macro- and microsegregation in semiconductor crystals grown from the melt under the direction of August F Witt at the Massachusetts Institute of Technology SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT Symposium on 50 Years of Progress in Crystal Growth CY AUG 04-09, 2002 CL Seattle, WA SP Amer Assoc Crystal Growth DE heat pipes; impurity striations; magnetic fields; segregation; bulk crystal growth ID GA-DOPED GE; VERTICAL BRIDGMAN CONFIGURATION; LATERAL SOLUTE SEGREGATION; SOLID-LIQUID INTERFACE; MAGNETIC-FIELD; SINGLE CRYSTALS; QUANTITATIVE-ANALYSIS; UNIDIRECTIONAL SOLIDIFICATION; IMPURITY DISTRIBUTION; DOPANT SEGREGATION AB The birth of the modern age of semiconductor electronics in the 1950s required the production of single crystals from the melt. In the early years of this technology, crystals exhibited non-uniform distributions of chemical and structural defects, which directly affected devices produced from this material. Uniform distribution and control of dopants, unintentional impurities, and native defects were identified Lis critical requirements for continued advances in device technology. However, since at that time fundamental understanding of cause and effect relationships between crystal growth parameters and the ultimate properties of the materials produced was absent, such desirable properties were unattainable. Nevertheless, it was recognized that segregation plays a key role in the creation of non-uniformities. Macrosegregation, a consequence of the directional solidification process, is generally controlled by diffusion and convective melt flows. Microsegregation is governed by local perturbations at the crystal-melt interface. Time-dependent thermal and melt velocity fields at the crysltal-melt interface impact the microscopic rate of growth and the solute diffusion boundary layer. Identification of the fundamental parameters that govern axial and radial macro- and microsegregation during bulk semiconductor crystal growth was the research focus during the early years. Key contributions were made by Prof. August F. Witt and his research group. One of the major contributions was the development of quantitative analytical tools for characterization of the crystal growth process. These tools provided the foundation for understanding the origin and nature of segregation phenomena during crystal growth from the melt. This paper is a brief review of his work. (C) 2004 Elsevier B.V. All rights reserved. C1 MIT, Lincoln Lab, Lexington, MA 02420 USA. MA COM Inc, Lowell, MA 01851 USA. Cape Simulat Inc, Natick, MA 01760 USA. NASA Headquarters, Phys Sci Res Div, Washington, DC 20546 USA. RP Wang, CA (reprint author), MIT, Lincoln Lab, Lexington, MA 02420 USA. EM wang@ll.mit.edu NR 52 TC 10 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR 31 PY 2004 VL 264 IS 4 BP 565 EP 577 DI 10.1016/j.jcrysgro.2003.12.043 PG 13 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 809QO UT WOS:000220651400008 ER PT J AU Hakkinen, S Proshutinsky, A AF Hakkinen, S Proshutinsky, A TI Freshwater content variability in the Arctic Ocean SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article DE fresh water; Arctic; variability ID NORTHERN NORTH-ATLANTIC; SEA-ICE VOLUME; THERMOHALINE CIRCULATION; CLIMATE VARIABILITY; OSCILLATION; HEMISPHERE; SIMULATION; REGIMES; HEIGHT; STRAIT AB [1] Arctic Ocean model simulations have revealed that the Arctic Ocean has a basin-wide oscillation with cyclonic and anticyclonic circulation anomalies (Arctic Ocean Oscillation (AOO)) that has a prominent decadal variability [Proshutinsky and Johnson, 1997]. This study explores how the simulated AOO affects the Arctic Ocean stratification and its relationship to the sea ice cover variations. The simulation uses the Princeton Ocean Model coupled to sea ice [Hakkinen and Mellor, 1992; Hakkinen, 1999]. The surface forcing is based on National Centers for Environmental Prediction/National Center for Atmospheric Research Reanalysis and its climatology, of which the latter is used to force the model spin-up phase. Our focus is to investigate the competition between ocean dynamics and ice formation/melt on the Arctic basin-wide freshwater balance. We find that changes in the Atlantic water inflow can explain almost all of the simulated freshwater anomalies in the main Arctic basin. The Atlantic water inflow anomalies are an essential part of AOO, which is the wind driven barotropic response to the Arctic Oscillation (AO). The baroclinic response to AO, such as Ekman pumping in the Beaufort Gyre, and ice melt/freeze anomalies in response to AO are less significant considering the whole Arctic freshwater balance. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. RP Hakkinen, S (reprint author), NASA, Goddard Space Flight Ctr, Code 971, Greenbelt, MD 20771 USA. EM sirpa.hakkinen@nasa.gov RI Hakkinen, Sirpa/E-1461-2012 NR 30 TC 54 Z9 56 U1 1 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 EI 2169-9291 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAR 31 PY 2004 VL 109 IS C3 AR C03051 DI 10.1029/2003JC001940 PG 17 WC Oceanography SC Oceanography GA 811AO UT WOS:000220745000002 ER PT J AU Clack, D Kasper, JC Lazarus, AJ Steinberg, JT Farrell, WM AF Clack, D Kasper, JC Lazarus, AJ Steinberg, JT Farrell, WM TI Wind observations of extreme ion temperature anisotropies in the lunar wake SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PLASMA; INSTABILITY; SPACECRAFT AB We describe Wind observations of two lunar wake encounters which occurred on 12-13 November 1996 and 18 July 2002. The observations were made at downstream distances of around 25 and 15 lunar radii (R-L), respectively. Both encounters occurred prior to the spacecraft entering the lunar shadow; one event took place within the magnetosheath. A characteristic feature of the lunar wake is the presence of two counterstreaming ion beams drawn in from either flank. We find that both ion components exhibit an extreme temperature anisotropy, often with T(perpendicular to)similar to10T(parallel to). The anisotropy is greatest in the central wake region. It appears that the anisotropy arises through the conservation of adiabatic invariants as solar wind plasma expands to fill in the cavity behind the Moon. Despite their large anisotropy, the proton distributions appear stable to the cyclotron instability. Correlated field and flow directional changes show that the wake geometry is dependent upon the prevailing magnetic field orientation. C1 MIT, Ctr Space Res, Cambridge, MA 02139 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Clack, D (reprint author), Swedish Inst Space Phys, Box 537, SE-75121 Uppsala, Sweden. EM dc@irfu.se RI Kasper, Justin/D-1152-2010; Farrell, William/I-4865-2013 OI Kasper, Justin/0000-0002-7077-930X; NR 13 TC 25 Z9 25 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 30 PY 2004 VL 31 IS 6 AR L06812 DI 10.1029/2003GL018298 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 810ZX UT WOS:000220743300001 ER PT J AU Thomason, LW Burton, SP Iyer, N Zawodny, JM Anderson, J AF Thomason, LW Burton, SP Iyer, N Zawodny, JM Anderson, J TI A revised water vapor product for the Stratospheric Aerosol and Gas Experiment (SAGE) II version 6.2 data set SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE water vapor; stratosphere; SAGE II ID EXPERIMENT-II; EXTINCTION MEASUREMENTS; TRENDS AB [1] The Stratospheric Aerosol and Gas Experiment (SAGE) II water vapor retrieval process has been updated to reflect a new understanding of the instrument performance. Primarily, this is reflected in a shifted spectral response for the primary water channel near 935 nm for the period after January 1986. In addition, the water vapor and ozone spectroscopy, aerosol clearing process, and error estimation have been updated. The end result is that the measurement bias observed in version 6.1 and earlier versions has been effectively eliminated. The sensitivity to aerosol has been reduced, so that the recommended upper limit for usable water vapor is now 3 x 10(-4) km(-1) in 1020-nm aerosol extinction. The comparable value for version 6.1 was similar to 2 x 10(-5) km(-1), or 10 times more sensitive than in the new version. The impact of the channel drift on the retrieved water vapor relative to the simple model employed in this version will be difficult to separate from geophysical change, and therefore caution is recommended in evaluating trends derived from this data set. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Sci Applicat Int Corp, Hampton, VA USA. Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. RP Thomason, LW (reprint author), NASA, Langley Res Ctr, 23A Langley Blvd,Mail Stop 475, Hampton, VA 23681 USA. EM l.w.thomason@larc.nasa.gov; s.p.burton@larc.nasa.gov; n.iyer@larc.nasa.gov; j.m.zawodny@larc.nasa.gov; john.anderson@hamptonu.edu NR 23 TC 35 Z9 35 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 30 PY 2004 VL 109 IS D6 AR D06312 DI 10.1029/2003JD004465 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 811AI UT WOS:000220744400006 ER PT J AU Voorhies, CV AF Voorhies, CV TI Narrow-scale flow and a weak field by the top of Earth's core: Evidence from Orsted, Magsat, and secular variation SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article DE geomagnetism; core field; core flow ID GEOMAGNETIC-FIELD; MANTLE BOUNDARY; MAGNETIC-FIELD; INNER-CORE; OUTER-CORE; MODEL; SPECTRUM; VISCOSITY; OSCILLATIONS; MOTIONS AB To test two hypotheses against seismology, the Orsted initial field model is used to estimate the radius of Earth's core by spectral methods. The model coefficients are used to compute the mean-square magnetic flux density in spherical harmonics of degree n on the reference sphere of radius a=6371.2 km, which is an observational spectrum R-n. The theoretical spectrum tested, {R-n(c)}=K(n+1/2)[(n(n+1)](-1)(c/a)(2n+4), is obtained from the hypotheses of narrow-scale flow and a dynamically weak magnetic field near the top of Earth's core; it describes a low-degree, core source magnetic energy range. Core radius c and amplitude K are estimated by fitting log theoretical to log observational spectra at low degrees. Estimates of c from R-n of degrees 1 through N vary between 3441 and 3542 km as N increases from 4 to 12. None of these estimates differ significantly from the seismologic core radius of 3480 km. Significant differences do occur if N exceeds 12, which is consistent with appreciable noncore, crustal source fields at degrees 13 and above, or if other spectral forms are assumed. Similar results are obtained from the 1980 epoch Magsat model CM3. One way to deduce {R-n(c)} uses an expectation spectrum for low-degree secular variation (SV) induced by narrow-scale flow near the top of Earth's core, {F-n(c)}=Cn(n+1/2)(n+1)(c/a)(2n+4). The value of c obtained by fitting this form to the mean observational SV spectrum from model GSFC 9/80 is 3470+/-91 km, also in accord with seismologic estimates. This test of the narrow-scale flow hypothesis is independent of the weak field hypothesis. The agreement between SV, Magsat, Orsted, and seismologic estimates of core radius means the hypotheses pass these tests. Additional tests are described. C1 NASA, Goddard Space Flight Ctr, Geodynam Branch, Greenbelt, MD 20771 USA. RP Voorhies, CV (reprint author), NASA, Goddard Space Flight Ctr, Geodynam Branch, Code 921, Greenbelt, MD 20771 USA. EM coerte.v.voorhies@nasa.gov RI Voorhies, Coerte/D-4672-2012 NR 69 TC 19 Z9 19 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAR 30 PY 2004 VL 109 IS B3 AR B03106 DI 10.1029/2003JB002833 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 811AT UT WOS:000220745500002 ER PT J AU Xie, H Ofman, L Lawrence, G AF Xie, H Ofman, L Lawrence, G TI Cone model for halo CMEs: Application to space weather forecasting SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE coronal mass ejections; space weather; cone model ID CORONAL MASS EJECTIONS; MAJOR GEOMAGNETIC STORMS; MAGNETIC CLOUDS; SOLAR FILAMENTS; YOHKOH SXT; INTERPLANETARY; TRANSIENT; EVENTS; LASCO; ACCELERATION AB In this study, we present an innovative analytical method to determine the angular width and propagation orientation of halo Coronal Mass Ejections (CMEs). The relation of CME actual speed with apparent speed and its components measured at different position angle has been investigated. The present work is based on the cone model proposed by Zhao et al. [2002]. We have improved this model by (1) eliminating the ambiguity via a new analytical approach, (2) using direct measurements of projection onto the plane of the sky (POS), (3) determining the actual radial speeds from projection speeds at different position angles to clarify the uncertainty of projection speeds in previous empirical models. Our analytical approach allows us to use coronagraph data to determine accurately the geometrical features of POS projections, such as major axis, minor axis, and the displacement of the center of its projection, and to determine the angular width and orientation of a given halo CME. Our approach allows for the first time the determination of the actual CME speed, width, and source location by using coronagraph data quantitatively and consistently. The method greatly enhances the accuracy of the derived geometrical and kinematical properties of halo CMEs, and can be used to optimize SpaceWeather forecasts. The applied model predications are in good agreement with observations. C1 Catholic Univ Amer, Washington, DC 20064 USA. RP Xie, H (reprint author), NASA, Goddard Space Flight Ctr, Code 682, Greenbelt, MD 20771 USA. EM hong@aurora.nascom.nasa.gov; ofman@waves.gsfc.nasa.gov; gareth.lawrence@oma.be NR 36 TC 131 Z9 136 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 30 PY 2004 VL 109 IS A3 AR A03109 DI 10.1029/2003JA010226 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 811AX UT WOS:000220745900001 ER PT J AU Jacob, F Petitcolin, F Schmugge, T Vermote, E French, A Ogawa, K AF Jacob, F Petitcolin, F Schmugge, T Vermote, E French, A Ogawa, K TI Comparison of land surface emissivity and radiometric temperature derived from MODIS and ASTER sensors SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE MIR/TIR remote sensing; surface emissivity and radiometric temperature; MODIS; ASTER; TISIE; TES; atmospheric corrections; spatial variability ID IMAGING SPECTRORADIOMETER MODIS; THERMAL INFRARED DATA; REMOTE-SENSING DATA; BIDIRECTIONAL REFLECTIVITY; DIRECTIONAL EMISSIVITY; RESEDA EXPERIMENT; ANALYSIS SYSTEM; SVAT MODELS; ALGORITHM; SEPARATION AB This study compared surface emissivity and radiometric temperature retrievals derived from data collected with the MODerate resolution Imaging Spectroradiometer (MODIS) and Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER) sensors, onboard the NASA's Earth Observation System (EOS)-TERRA satellite. Two study sites were selected: a semi-arid area located in northern Chihuahuan desert, USA, and a Savannah landscape located in central Africa. Atmospheric corrections were performed using the MODTRAN 4 atmospheric radiative transfer code along with atmospheric profiles generated by the National Center for Environmental Predictions (NCEP). Atmospheric radiative properties were derived from MODTRAN 4 calculations according to the sensor swaths, which yielded different strategies from one sensor to the other. The MODIS estimates were then computed using a designed Temperature-Independent Spectral Indices of Emissivity (TISIE) method. The ASTER estimates were derived using the Temperature Emissivity Separation (TES) algorithm. The MODIS and ASTER radiometric temperature retrievals were in good agreement when the atmospheric corrections were similar, with differences lower than 0.9 K. The emissivity estimates were compared for MODIS/ASTER matching bands at 8.5 and 11 mum. It was shown that the retrievals agreed well, with RMSD ranging from 0.005 to 0.015, and biases ranging from -0.01 to 0.005. At 8.5 mum, the ranges of emissivities from both sensors were very similar. At 11 mum, however, the ranges of MODIS values were broader than those of the ASTER estimates. The larger MODIS values were ascribed to the gray body problem of the TES algorithm, whereas the lower MODIS values were not consistent with field references. Finally, we assessed the combined effects of spatial variability and sensor resolution. It was shown that for the study areas we considered, these effects were not critical. (C) 2004 Elsevier Inc. All rights reserved. C1 PURPAN Ecole Super Agr, Dept Sci & Methodes, Lab Teledetect & Gest Terr, F-31076 Toulouse 3, France. USDA ARS, Hydrol & Remote Sensing Lab, BARC W, Beltsville, MD 20705 USA. ACRI ST, F-06904 Sophia Antipolis, France. Univ Maryland, Dept Geog, Greenbelt, MD 20771 USA. Univ Maryland, NASA, GSFC, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Natl Res Council Associateship, Greenbelt, MD 20771 USA. RP PURPAN Ecole Super Agr, Dept Sci & Methodes, Lab Teledetect & Gest Terr, 75 Voie TOEC, F-31076 Toulouse 3, France. EM frederic.jacob@esa-purpan.fr RI Ogawa, Kenta/B-7687-2008; Jacob, Frederic/A-5946-2011; Vermote, Eric/K-3733-2012 OI Jacob, Frederic/0000-0002-2491-3096; NR 51 TC 68 Z9 72 U1 1 U2 23 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 EI 1879-0704 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAR 30 PY 2004 VL 90 IS 2 BP 137 EP 152 DI 10.1016/j.rse.2003.11.015 PG 16 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 805VM UT WOS:000220393800001 ER PT J AU Jo, YH Yan, XH Pan, JY Liu, WT He, MX AF Jo, YH Yan, XH Pan, JY Liu, WT He, MX TI Sensible and latent heat flux in the tropical Pacific from satellite multi-sensor data SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE heat flux; sensible heat flux; latent heat flux; Bowen ratio; wind divergence ID SEA-SURFACE TEMPERATURE; EQUATORIAL PACIFIC; OCEAN; VARIABILITY; ROUGHNESS; STABILITY; BUDGET; VAPOR AB Satellite multi-sensor data is used to derive sensible heat flux (SHF), Bowen ratio (Bo), and thus latent heat flux (LHF) in the tropical Pacific. The temperature differences at the air-sea interface are determined empirically for regions where strong deep air convection is present due to the buoyancy force. The vertical airflow results in surface wind divergence, which is estimated from scatterometer wind vector fields. The areas of positive temperature differences between sea surface temperature and atmospheric temperature estimated using surface wind divergence and in situ measurements are highly consistent in the tropical Pacific, especially in two convergence zones, i.e., the Intertropical Convergence Zone (ITCZ), and the South Pacific Convergence Zone (SPCZ). The bulk formulated SHF, determined by surface wind divergence (SHFBWD), is compared with a long-term time series (January 1993-December 1999) of the SHF from the National Centers for Environmental Prediction (NCEP) reanalyzed model data (SHFM). In the ITCZ, the correlation coefficients and the Root Mean Square (RMS) differences between SHFBWD and SHFM are over 70% and in the order of less than 4 W/m(2), respectively. Furthermore, the bulk formulated latent heat flux (LHFB) is obtained using the empirical Bowen ratio (1300 and SHFBWD. The Bo(E) for the tropical Pacific was estimated using only sea surface temperature, which is valid when the vapor is saturated near sea surface. The RMS differences between SHFBWD and LHFB are estimated as 3.5 and 39.3 W/m(2), respectively. In addition, the differences of SHFBWD and LHFB during the boreal winters are smaller than that in the boreal summers. Finally, in order to study spatial and temporal variations, we apply Empirical Orthogonal Function (EOF) analysis to SHFBWD and LHFB and compare with EOF analysis of Coupled Ocean and Atmosphere Data Set (COADS)'s SHF and LHF. (C) 2004 Elsevier Inc. All rights reserved. C1 Univ Delaware, Grad Coll Marine Studies, Newark, DE 19716 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Ocean Univ Qingdao, Ocean Remote Sensing Inst, Qingdao 266003, Peoples R China. RP Yan, XH (reprint author), Univ Delaware, Grad Coll Marine Studies, 209 Robinson Hall,S Coll Ave, Newark, DE 19716 USA. EM xiaohai@udel.edu NR 26 TC 6 Z9 6 U1 0 U2 7 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAR 30 PY 2004 VL 90 IS 2 BP 166 EP 177 DI 10.1016/j.rse.2003.12.003 PG 12 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 805VM UT WOS:000220393800003 ER PT J AU Kimball, JS McDonald, KC Running, SW Frolking, SE AF Kimball, JS McDonald, KC Running, SW Frolking, SE TI Satellite radar remote sensing of seasonal growing seasons for boreal and subalpine evergreen forests SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE radar remote sensing; growing season; evergreen forest; phenology; NPP; seawinds; boreal forest; freeze-thaw; BIOME-BGC ID NASA SCATTEROMETER NSCAT; CARBON BALANCE; HIGH-ELEVATION; CLIMATE; CO2; PRODUCTIVITY; EVAPOTRANSPIRATION; SEQUESTRATION; VEGETATION; EXCHANGE AB We evaluated whether satellite radar remote sensing of landscape seasonal freeze-thaw cycles provides an effective measure of active growing season timing and duration for boreal and subalpine evergreen forests. Landscape daily radar backscatter measurements from the SeaWinds scatterometer on-board the QuikSCAT satellite were evaluated across a regional network of North American coniferous forest sites for 2000 and 2001. Radar remote sensing measurements of the initiation and length of the growing season corresponded closely with both site measurements and ecosystem process model (BIOME-BGC) simulations of these parameters because of the sensitivity of the K.-band scatterometer to snow cover freeze-thaw dynamics and associated linkages between growing season initiation and the timing of seasonal snowmelt. In contrast, remote sensing estimates of the timing of growing season termination were either weakly or not significantly associated with site measurements and model simulation results, due to the relative importance of light availability and other environmental controls on stand phenology in the fall. Regional patterns of estimated annual net primary production (NPP) and component photosynthetic and autotrophic respiration rates for the evergreen forest sites also corresponded favorably with remote sensing estimates of the seasonal timing of spring thaw and associated growing season length, indicating the importance of these parameters in determining spatial and temporal patterns of NPP and the potential utility of satellite radar remote sensing for regional monitoring of the terrestrial biosphere. (C) 2004 Elsevier Inc. All rights reserved. C1 Univ Montana, Flathead Lake Biol Stn, Div Biol Sci, Polson, MT 59860 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Montana, Dept Ecosyst & Conservat Sci, Numer Terradynam Simulat Grp, Missoula, MT 59812 USA. Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA. Univ New Hampshire, Dept Earth Sci, Durham, NH 03824 USA. RP Kimball, JS (reprint author), Univ Montana, Flathead Lake Biol Stn, Div Biol Sci, 311 Bio Stn Lane, Polson, MT 59860 USA. EM johnk@ntsg.umt.edu NR 41 TC 94 Z9 101 U1 3 U2 27 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAR 30 PY 2004 VL 90 IS 2 BP 243 EP 258 DI 10.1016/j.rse.2004.01.002 PG 16 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 805VM UT WOS:000220393800009 ER PT J AU Greenblatt, RJ Work, TM Balazs, GH Sutton, CA Casey, RN Casey, JW AF Greenblatt, RJ Work, TM Balazs, GH Sutton, CA Casey, RN Casey, JW TI The Ozobranchus leech is a candidate mechanical vector for the fibropapilloma-associated turtle herpesvirus found latently infecting skin tumors on Hawaiian green turtles (Chelonia mydas) SO VIROLOGY LA English DT Article DE quantitative PCR; marine turtle; leech; vector; fibropapillomatosis; fibropapilloma-associated turtle herpesvirus; green turtle herpesvirus; latent ID MULTICENTRIC CASTLEMANS-DISEASE; PRIMARY EFFUSION LYMPHOMA; KAPOSIS-SARCOMA; CUTANEOUS FIBROPAPILLOMAS; MARINE TURTLES; TRANSMISSION; HUMAN-HERPESVIRUS-8; SEQUENCES; PATHOGENS; EXPOSURE AB Fibropapillomatosis (FP) of marine turtles is a neoplastic disease of ecological concern. A fibropapilloma-associated turtle herpesvirus (FPTHV) is consistently present, usually at loads exceeding one virus copy per tumor cell. DNA from an array of parasites of green turtles (Chelonia mydas) was examined with quantitative PCR (qPCR) to determine whether any carried viral loads are sufficient to implicate them as vectors for FPTHV. Marine leeches (Ozobranchus spp.) were found to carry high viral DNA loads; some samples approached 10 million copies per leech. lsopycnic sucrose density gradient/qPCR analysis confirmed that some of these copies were associated with particles of the density of enveloped viruses. The data implicate the marine leech Ozobranchus as a mechanical vector for FPTHV. Quantitative RT-PCR analysis of FPTHV gene expression indicated that most of the FPTHV copies in a fibropapilloma have restricted DNA polymerase expression, suggestive of latent infection. (C) 2004 Elsevier Inc. All rights reserved. C1 Cornell Univ, Coll Vet Med, Dept Microbiol & Immunol, Vet Med Ctr, Ithaca, NY 14853 USA. Natl Wildlife Hlth Ctr, Honolulu Field Stn, United States Geol Survey, Honolulu, HI 96850 USA. Honolulu Lab, Pacific Isl Fisheries Sci Ctr, Natl Marine Fisheries Serv, Honolulu, HI 96822 USA. RP Casey, JW (reprint author), Cornell Univ, Coll Vet Med, Dept Microbiol & Immunol, Vet Med Ctr, C5-153, Ithaca, NY 14853 USA. EM jwc3@cornell.edu RI Work, Thierry/F-1550-2015 OI Work, Thierry/0000-0002-4426-9090 FU NIEHS NIH HHS [2T32 ES07052-26] NR 29 TC 47 Z9 53 U1 3 U2 10 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0042-6822 J9 VIROLOGY JI Virology PD MAR 30 PY 2004 VL 321 IS 1 BP 101 EP 110 DI 10.1016/j.virol.2003.12.026 PG 10 WC Virology SC Virology GA 807KB UT WOS:000220499300011 PM 15033569 ER PT J AU Snyder, GJ AF Snyder, GJ TI Application of the compatibility factor to the design of segmented and cascaded thermoelectric generators SO APPLIED PHYSICS LETTERS LA English DT Article AB Using thermoelectric compatibility, efficient thermoelectric generators are rationally designed. With examples, compatible and incompatible systems are explained and materials proposed for targeted development. The compatibility factor explains why segmentation of (AgSbTe2)(0.15)(GeTe)(0.85) (TAGS) with SnTe or PbTe produces little extra power, while filled skutterudite increases the efficiency from 10.5% to 13.6%. High efficiency generators are designed with compatible n-type La2Te3, and similar p-type material, while incompatible SiGe alloys actually reduce the efficiency. A refractory metal with high p-type thermopower (>100 muV/K) is required for development. Cascaded generators avoid the compatibility problem. The thermoelectric potential provides a simple derivation of. the cascading ratio. (C) 2004 American Institute of Physics. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM jsnyder@jpl.nasa.gov RI Snyder, G. Jeffrey/E-4453-2011; Snyder, G/I-2263-2015 OI Snyder, G. Jeffrey/0000-0003-1414-8682; NR 7 TC 103 Z9 109 U1 3 U2 63 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 29 PY 2004 VL 84 IS 13 BP 2436 EP 2438 DI 10.1063/1.1689396 PG 3 WC Physics, Applied SC Physics GA 808TN UT WOS:000220591500072 ER PT J AU Garvin, JB AF Garvin, JB TI Salty seas left imprint on Mars SO CHEMICAL & ENGINEERING NEWS LA English DT News Item C1 NASA, Washington, DC 20546 USA. RP Garvin, JB (reprint author), NASA, Washington, DC 20546 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0009-2347 J9 CHEM ENG NEWS JI Chem. Eng. News PD MAR 29 PY 2004 VL 82 IS 13 BP 5 EP 5 PG 1 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 807WJ UT WOS:000220531300009 ER PT J AU Boatz, JA Hinde, RJ Sheehy, JA Langhoff, PW AF Boatz, JA Hinde, RJ Sheehy, JA Langhoff, PW TI Theory of open-shell metal atoms in cryogenic clusters. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 AF Res Lab, Edwards AFB, CA 93524 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NASA, George C Marshall Space Flight Ctr, Dept Chem, Huntsville, AL USA. NASA, George C Marshall Space Flight Ctr, Prop Res Ctr, Huntsville, AL USA. Univ Calif San Diego, San Diego Supercom Ctr, La Jolla, CA 92093 USA. EM Jerry.Boatz@edwards.af.mil; langhoff@drifter.sdsc.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 305-PHYS BP U304 EP U305 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655701547 ER PT J AU Bottomley, LA Poggi, MA McFarland, AW Colton, JS Lillehei, PT AF Bottomley, LA Poggi, MA McFarland, AW Colton, JS Lillehei, PT TI Force spectroscopy of single walled carbon nanotubes for improved polymer composites. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. Georgia Inst Technol, George W Woodruff Sch Mech Engn, Atlanta, GA 30332 USA. NASA Langley, Adv Mat & Proc Branch, Hampton, VA USA. RI Lillehei, Peter/C-9196-2009 OI Lillehei, Peter/0000-0001-8183-9980 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 88-PMSE BP U501 EP U502 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655702540 ER PT J AU Chaban, GM AF Chaban, GM TI Vibrational spectroscopy of ions and radicals present in the interstellar medium and in planetary atmospheres: A theoretical study. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM chaban@nas.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 256-PHYS BP U283 EP U283 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655701498 ER PT J AU Fabrizio, E Ilhan, F Meador, MAB Johnston, C Leventis, N AF Fabrizio, E Ilhan, F Meador, MAB Johnston, C Leventis, N TI Epoxy crossilinked silica aerogels (X-aerogels). SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Ohio Aerosp Inst, Cleveland, OH 44142 USA. NASA, Glenn Res Ctr, Div Mat, Cleveland, OH USA. EM Eve.Fabrizio@grc.nasa.gov; Ulvi.F.llhan@grc.nasa.gov NR 0 TC 0 Z9 0 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 201-COLL BP U835 EP U835 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655602822 ER PT J AU Gaddy, GA Miner, GA Stoakley, DM Locke, EP Mills, G AF Gaddy, GA Miner, GA Stoakley, DM Locke, EP Mills, G TI Method for the controlled formation and placement of metal layers in polyimide films. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 USA, Res Lab, Sensors & Electron Devices Directorate, AMSRL SE L Gaddy, Adelphi, MD 20783 USA. NASA, Langley Res Ctr, Adv Aricraft Program Mat Grp, Hampton, VA USA. Auburn Univ, Dept Chem, Auburn, AL 36849 USA. EM ggaddy@arl.army.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 203-PMSE BP U520 EP U520 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655702655 ER PT J AU Ilhan, F Tyson, DS Smith, D Meador, MAB Meador, MA AF Ilhan, F Tyson, DS Smith, D Meador, MAB Meador, MA TI Diels-Alder trapping of photochemically generated dienes with acrylic esters: A novel approach to photocured polymer film development. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Ohio Aerosp Inst, Div Mat, Cleveland, OH 44142 USA. NASA, Glenn Res Ctr, Div Mat, Cleveland, OH USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. EM Ulvi.F.Ilhan@grc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 123-POLY BP U366 EP U366 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655701911 ER PT J AU Jaffe, RL AF Jaffe, RL TI Modeling the interaction of ethylene diamine coated carbon nanotubes with water. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Nanotechnol Branch, Moffett Field, CA 94035 USA. EM rjaffe@mail.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 247-IEC BP U1270 EP U1270 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655604307 ER PT J AU Kojiro, DR Holland, PM Stimac, RM Kaye, WJ Takeuchi, N AF Kojiro, DR Holland, PM Stimac, RM Kaye, WJ Takeuchi, N TI Analytical instrument for determining the composition of surface materials and ices in the solar system: Mini-CIDEX to tide. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Div Space Sci, Exobiol Branch, Moffett Field, CA 94035 USA. EM Daniel.R.Kojiro@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 142-ANYL BP U101 EP U101 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655600430 ER PT J AU Leventis, N Rawashdeh, AM Elder, IA Yang, JH Dass, A Sotiriou-Leventis, C AF Leventis, N Rawashdeh, AM Elder, IA Yang, JH Dass, A Sotiriou-Leventis, C TI Silica aerogels doped with Ru(II) tris(1,10-phenanthroline)-electron acceptor DYADS: Improving the dynamic range, sensitivity and response time of sol-gel based optical oxygen sensors SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 NASA, Glenn Res Ctr, Div Mat, Cleveland, OH 44135 USA. Univ Missouri, Dept Chem, Rolla, MO 65401 USA. EM Nicholas.Leventis@grc.nasa.gov NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 227-COLL BP U840 EP U840 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655602848 ER PT J AU Leventis, N AF Leventis, N TI Magnetohydrodynamic and paramagnetic phenomena in electrochemistry with diamagnetic and ferromagnetic millielectrodes SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 NASA Glenn Res Ctr, Mat Div, Cleveland, OH 44135 USA. Univ Missouri, Dept Chem, Rolla, MO 65211 USA. EM Nicholas.Leventis@grc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 005-ANYL BP U79 EP U79 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655600293 ER PT J AU Li, C Lei, B Fan, W Zhou, CW AF Li, C Lei, B Fan, W Zhou, CW TI Multilevel molecular memory based on nanowire/molecular wire heterostructures. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Univ So Calif, Dept EE Phys, Los Angeles, CA 90089 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 099-INOR BP U1301 EP U1302 PN 1 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655604457 ER PT J AU Meyyappan, M Khare, B Wilhite, P AF Meyyappan, M Khare, B Wilhite, P TI Functionalization of SWNTS using a cold plasma. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. EM meyya@orbit.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 239-IEC BP U1269 EP U1269 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655604299 ER PT J AU Nguyen, Q Opila, E AF Nguyen, Q Opila, E TI Oxidation of ultra-high temperature ceramics in water vapor. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 NASA, Glenn Res Ctr, Environm Durabil Branch, Cleveland, OH 44135 USA. Cleveland State Univ, Cleveland, OH 44115 USA. EM Quynhgiao.N.Nguyen@NASA.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 333-INOR BP U1418 EP U1418 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655604691 ER PT J AU Nikolaev, P Arepalli, S Gorelik, O Hadjiev, V Holmes, W Files, B Yowell, L AF Nikolaev, P Arepalli, S Gorelik, O Hadjiev, V Holmes, W Files, B Yowell, L TI Protocol for the characterization of single-wall carbon nanotube material quality. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 NASA, GB Tech Inc, JSC, Mat & Proc Branch,Nanotube Team,Lockheed Martin C, Houston, TX 77058 USA. Univ Houston, Houston, TX USA. EM pasha.nikolaev1@jsc.nasa.gov RI Arepalli, Sivaram/A-5372-2010; Nikolaev, Pavel/B-9960-2009; Hadjiev, Viktor/A-7069-2008 OI Hadjiev, Viktor/0000-0001-8579-9357 NR 0 TC 0 Z9 0 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 127-IEC BP U1251 EP U1251 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655604187 ER PT J AU Park, C Wise, KE Ounaies, Z Smith, MW Lowther, SE Lillehei, PT Siochi, EJ Harrison, JS AF Park, C Wise, KE Ounaies, Z Smith, MW Lowther, SE Lillehei, PT Siochi, EJ Harrison, JS TI Evaluation of stable dispersion of SWNT in nanocomposites. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 NASA, Langley Res Ctr, Natl Inst Aerosp, Adv Mat & Proc Branch, Hampton, VA 23681 USA. Virginia Commonwealth Univ, Richmond, VA 23284 USA. EM c.ark@larc.nasa.gov RI Lillehei, Peter/C-9196-2009 OI Lillehei, Peter/0000-0001-8183-9980 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 261-IEC BP U1273 EP U1273 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655604321 ER PT J AU Park, C Wise, KE Ounaies, Z Pawlowski, KJ Working, DC Lowther, SE Lillehei, PT Siochi, EJ Harrison, JS AF Park, C Wise, KE Ounaies, Z Pawlowski, KJ Working, DC Lowther, SE Lillehei, PT Siochi, EJ Harrison, JS TI Multifunctional and structural SWNT-polymer nanocomposite fibers SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Natl Inst Aerosp, Hampton, VA 23681 USA. NASA Langley, Adv Mat & Proc Branch, Hampton, VA USA. Virginia Commonwealth Univ, Richmond, VA 23284 USA. EM c.park@larc.nasa.gov RI Lillehei, Peter/C-9196-2009 OI Lillehei, Peter/0000-0001-8183-9980 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 35-PMSE BP U474 EP U475 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655702487 ER PT J AU Poggi, MA Bottomley, LA McFarland, AW Colton, JS Lillehei, PT AF Poggi, MA Bottomley, LA McFarland, AW Colton, JS Lillehei, PT TI Fly-fishing with single walled carbon nanotubes. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. Georgia Inst Technol, George W Woodruff Sch Mech Engn, Atlanta, GA 30332 USA. NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23665 USA. EM poggi@chemistry.gatech.edu RI Lillehei, Peter/C-9196-2009 OI Lillehei, Peter/0000-0001-8183-9980 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 497-COLL BP U883 EP U884 PN 1 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655603118 ER PT J AU Rouse, JH Lillehei, PT Sanderson, J Siochi, EJ AF Rouse, JH Lillehei, PT Sanderson, J Siochi, EJ TI Bottom-up assembly of polymer/single walled carbon nanotube films using donor-acceptor interactions and their post-synthetic modification to create novel polymermanotube/silica films. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Natl Inst Aerosp, Hampton, VA 23666 USA. NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA USA. EM j.h.rouse@larc.nasa.gov RI Lillehei, Peter/C-9196-2009 OI Lillehei, Peter/0000-0001-8183-9980 NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 121-COLL BP U822 EP U822 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655602742 ER PT J AU Rouse, JH Siochi, EJ AF Rouse, JH Siochi, EJ TI Potential for single walled carbon nanotube purification via polymer-assisted dispersion in alcohols. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Natl Inst Aerosp, Hampton, VA 23666 USA. NASA, Langley Res Ctr, Adv Mat & Proc Banch, Hampton, VA USA. EM j.h.rouse@larc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 269-PHYS BP U285 EP U285 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655701511 ER PT J AU Stone, JN Ferrante, RF Moore, MH AF Stone, JN Ferrante, RF Moore, MH TI Low temperature IR spectroscopy of water and ammonia ices. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. NASA, Goddard Space Flight Ctr, Astrochem Branch, Greenbelt, MD USA. EM m046684@usna.edu NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 321-PHYS BP U307 EP U307 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655701563 ER PT J AU Taylor, CD Tomasek, AJ Ticich, TM Vander Wal, RL AF Taylor, CD Tomasek, AJ Ticich, TM Vander Wal, RL TI Fire safety: Analysis of aerosols from smoldering electronics components and insulation materials. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Centenary Coll Louisiana, Dept Chem, Shreveport, LA 71134 USA. NASA, Glenn Res Ctr, NCMR, Cleveland, OH USA. EM ctaylor@centenary.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 741-CHED BP U610 EP U610 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655602015 ER PT J AU Tyson, DS Kinder, JD Meador, MA AF Tyson, DS Kinder, JD Meador, MA TI New class of symmetrically substituted dioxapyrenes: A synthetic report with special focus on optical properties SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Ohio Aerosp Inst, Div Mat, Cleveland, OH 44135 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM Daniel.S.Tyson@grc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 413-ORGN BP U173 EP U173 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655700922 ER PT J AU Tyson, DS Meador, MA AF Tyson, DS Meador, MA TI 4,8-ditoluoyl-1,5-dihydroxynaphthalene: Efficient synthesis of multi-gram quantities SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Ohio Aerosp Inst, Div Mat, Cleveland, OH 44135 USA. NASA, Glenn Res Ctr, Div Mat, Cleveland, OH 44135 USA. EM Daniel.S.Tyson@grc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 117-ORGN BP U122 EP U122 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655700626 ER PT J AU Wang, JJ Myung, NV AF Wang, JJ Myung, NV TI Bio-electrochemical nanowire sensor arrays. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th National Meeting of the American-Chemical Society CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Univ Calif Los Angeles, Dept Chem Engn, Los Angeles, CA 90095 USA. Univ Calif Riverside, Dept Environm Chem & Engn, Riverside, CA 92521 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. EM wangjj@ucla.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 165-ANYL BP U104 EP U104 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AJ UT WOS:000223655600453 ER PT J AU Wang, L Harris, FW Chuang, KC AF Wang, L Harris, FW Chuang, KC TI Low melt viscosity resins for resin transfer molding. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Univ Akron, Maurice Morton Inst Polymer Sci, Akron, OH 44325 USA. NASA, Glenn Res Ctr, Cleveland, OH USA. EM lw12@uakron.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA POLY-145 BP U369 EP U369 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655701933 ER PT J AU Xue, CC Meador, MAB Eby, RK Cheng, SZD Ge, JJ Cubon, VA AF Xue, CC Meador, MAB Eby, RK Cheng, SZD Ge, JJ Cubon, VA TI Inter and intra molecular phase separation environment effects on PI-PEO block copolymers for batteries and fuel cells SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Univ Akron, Maurice Morton Inst Polymer Sci, Akron, OH 44325 USA. NASA, Div Mat, Glenn Res Ctr, Cleveland, OH 44135 USA. EM cxue@uakron.edu NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 454-POLY BP U433 EP U433 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655702242 ER PT J AU Xue, CC Ilhan, F Jin, S Cheng, SZD Meador, MA Eby, RK AF Xue, CC Ilhan, F Jin, S Cheng, SZD Meador, MA Eby, RK TI Hydrogen bonding and molecular conformation in self-assembled discotic liquid crystals. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Univ Akron, Maurice Morton Inst Polymer Sci, Akron, OH 44325 USA. Ohio Aerosp Inst, Cleveland, OH USA. NASA, Div Mat, Glenn Res Ctr, Cleveland, OH USA. EM cxue@uakron.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 89-POLY BP U361 EP U361 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655701877 ER PT J AU Yang, JH Dass, A Sotiriou-Leventis, C Leventis, N AF Yang, JH Dass, A Sotiriou-Leventis, C Leventis, N TI Synthesis and photoluminescent properties of arylethynyl substituted 9,10-anthraquinones. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Univ Missouri, Dept Chem, Rolla, MO 65409 USA. NASA, Glenn Res Ctr, Polymer Branch, Div Mat, Cleveland, OH USA. EM jynn8@umr.edu NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 321-ORGN BP U157 EP U157 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655700830 ER PT J AU Yang, JH Monem, A Rawashdeh, M Oh, WS Sotiriou-Leventis, C Leventis, N AF Yang, JH Monem, A Rawashdeh, M Oh, WS Sotiriou-Leventis, C Leventis, N TI Redox-active star molecules incorporating the 4-benzoylpyridinium cation: Implications for the charge transfer efficiency along branches vs. across the perimeter in dendrimers. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 227th ACS National Meeting CY MAR 28-APR 01, 2004 CL Anaheim, CA SP Amer Chem Soc C1 Univ Missouri, Dept Chem, Rolla, MO 65409 USA. NASA, Glenn Res Ctr, Polymer Branch, Div Mat, Cleveland, OH USA. EM jynn8@umr.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 28 PY 2004 VL 227 MA 320-ORGN BP U156 EP U157 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 851AK UT WOS:000223655700829 ER PT J AU Zeng, W Horwitz, JL Craven, PD Rich, FJ Moore, TE AF Zeng, W Horwitz, JL Craven, PD Rich, FJ Moore, TE TI The O+ density trough at 5000 km altitude in the polar cap SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE density trough; TIDE; polar cap; DMSP ID MASS-SPECTROMETER OBSERVATIONS; CLEFT ION FOUNTAIN; F-REGION; WIND; IONOSPHERE; MAGNETOPAUSE; OUTFLOW; MODEL; FLOWS AB At altitudes near 5000 km over the southern polar cap region of the terrestrial magnetosphere/ionosphere, the Thermal Ion Dynamics Experiment ( TIDE) on board the Polar satellite has observed O+ ion density trough regions, in which the O+ densities were at least one order of magnitude lower than the surrounding O+ densities. In the O+ density trough regions, the estimated O+ densities were generally lower than 0.01 per cc. The boundaries between normal density level regions and the trough density regions were usually abrupt transitions. From 1 December 1997 to 30 November 1998, polar cap O+ troughs in Polar/TIDE observations occurred at a frequency of about 48%. Statistical examination of the Polar perigee observations from 1 December 1997 to 30 November 1998 shows that the Polar perigee passes evenly covered the southern polar cap region, while the O+ density trough was always located on the nightside portion of the polar cap magnetosphere/ionosphere, and that invariant latitude spans of such troughs could be as large as 23degrees in extent. The trough occurrence displayed a strong seasonal dependence; in the winter season (e.g., for July in the Southern Hemisphere) the O+ ion density trough occurrence frequency ranged up to 92%, while in the summer season (e.g., for January in the Southern Hemisphere) it decreased to as low as 15%. Our statistical results show that the trough occurrence was generally anticorrelated with solar wind dynamic pressure in the solar wind dynamic pressure range 0.8-2.6 nanopascal. The O+ ion density trough occurrence appeared relatively independent of the geomagnetic Kp index, IMF Bz, and By conditions. However, as suggested by the seasonal dependence, the O+ ion density trough occurrence was strongly related to the solar zenith angle (SZA). In the SZA range 50degrees to 125degrees, the trough occurrence increased monotonically with SZA. In addition, we sought to determine consistent density and velocity signatures at lower altitudes associated the O+ ion density trough at 5000 km by examining the near-simultaneous O+ densities and vertical velocities observed by the DMSP satellite group orbiting at 840 km altitude. However, consistent correlations between the dual altitudes were not reliably established from the present examinations. C1 Univ Alabama, Ctr Space Plasma & Aeron Res, Huntsville, AL 35899 USA. NASA, George C Marshall Space Flight Ctr, Dept Space Sci, Natl Space Sci & Technol Ctr, Huntsville, AL 35805 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RP Zeng, W (reprint author), Univ Alabama, Ctr Space Plasma & Aeron Res, Huntsville, AL 35899 USA. EM zengw@cspar.uah.edu; horwitzj@cspar.uah.edu; paul.craven@msfc.nasa.gov; frederick.rich@hanscom.af.mil; thomas.e.moore@nasa.gov RI Moore, Thomas/D-4675-2012 OI Moore, Thomas/0000-0002-3150-1137 NR 24 TC 6 Z9 6 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 27 PY 2004 VL 109 IS A3 AR A03220 DI 10.1029/2003JA010210 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 809GT UT WOS:000220625900002 ER PT J AU Khosrawi, F Muller, R Irie, H Engel, A Toon, GC Sen, B Aoki, S Nakazawa, T Traub, WA Jucks, KW Johnson, DG Oelhaf, H Wetzel, G Sugita, T Kanzawa, H Yokota, T Nakajima, H Sasano, Y AF Khosrawi, F Muller, R Irie, H Engel, A Toon, GC Sen, B Aoki, S Nakazawa, T Traub, WA Jucks, KW Johnson, DG Oelhaf, H Wetzel, G Sugita, T Kanzawa, H Yokota, T Nakajima, H Sasano, Y TI Validation of CFC-12 measurements from the Improved Limb Atmospheric Spectrometer (ILAS) with the version 6.0 retrieval algorithm SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE CFC-12; ILAS; validation ID PROFILE OBSERVATIONS; ARCTIC VORTEX; TRACE GASES; OZONE; STRATOSPHERE; CHLORINE; DISTRIBUTIONS; CONSTITUENTS; RATIOS; N2O AB [1] Measurements of CFC-12 were made by the Improved Limb Atmospheric Spectrometer (ILAS) between 57degreesN and 72degreesN in the Northern Hemisphere and between 64degreesS and 89degreesS in the Southern Hemisphere. ILAS was launched on 17 August 1996 on board the Advanced Earth Observing Satellite (ADEOS). The ILAS validation balloon campaigns were carried out from Kiruna, Sweden (68degreesN, 21degreesE), in February and March 1997 and from Fairbanks, Alaska (65degreesN, 148degreesW), in April and May 1997. During these validation balloon campaigns, CFC-12 was measured with the in situ instruments ASTRID, BONBON, and SAKURA and the remote sensing spectrometers MIPAS-B, FIRS-2, and MkIV. ILAS version 6.0 CFC-12 profiles obtained at the nearest location to the validation balloon measurement are compared with these validation balloon measurements. The quality of ILAS CFC-12 data processed with the version 6.0 algorithm improved significantly compared to previous versions. Low relative differences between ILAS CFC-12 and the correlative measurements of about 10% were found between 13 and 20 km. The comparison of vertical profiles shows that ILAS CFC-12 data are useful below about 20-22 km inside the vortex and below about 25 km outside the vortex. However, at greater altitudes the relative percentage difference increases very strongly with increasing altitude. Further, correlations of CFC-12 with N2O show a good agreement with the correlative measurements for N2O values of N2O > 150 ppbv. In summary, ILAS CFC-12 data are now suitable for scientific studies in the lower stratosphere. C1 Natl Inst Environm Studies, Ozone Layer Res Project, Tsukuba, Ibaraki 3050053, Japan. Forschungszentrum Julich, ICG I, D-52425 Julich, Germany. Univ Frankfurt, Inst Meteorol, D-60325 Frankfurt, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Tohoku Univ, Ctr Atmospher & Ocean Studies, Grad Sch Sci, Sendai, Miyagi 9808578, Japan. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Forschungszentrum Karlsruhe, Inst Meteorol & Klimaforsch, D-76021 Karlsruhe, Germany. RP Khosrawi, F (reprint author), Natl Inst Environm Studies, Ozone Layer Res Project, Tsukuba, Ibaraki 3050053, Japan. EM f.khosrawi@fz-juelich.de; ro.mueller@fz-juelich.de; irie.hitoshi@nies.go.jp; an.engel@meteor.uni-frankfurt.de; toon@mark4sun.jpl.nasa.gov; sen@mark4sun.jpl.nasa.gov; aoki@mail.cc.tohoku.ac.jp; nakazawa@mail.tains.tohoku.ac.jp; traub@cfa.harvard.edu; kjucks@cfa.harvard.edu; d.g.johnson@larc.nasa.gov; hermann.oelhaf@imk.fzk.de; gerald.wetzel@imk.fzk.de; tsugita@nies.go.jp; kanzawa@ihas.nagoya-u.ac.jp; yoko@nies.go.jp; hide@nies.go.jp; sasano@nies.go.jp RI Sasano, Yasuhiro/C-2927-2009; Muller, Rolf/A-6669-2013; Wetzel, Gerald/A-7065-2013; Oelhaf, Hermann/A-7895-2013; Engel, Andreas/E-3100-2014 OI Sasano, Yasuhiro/0000-0001-7470-5642; Muller, Rolf/0000-0002-5024-9977; Engel, Andreas/0000-0003-0557-3935 NR 23 TC 12 Z9 12 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 26 PY 2004 VL 109 IS D6 AR D06311 DI 10.1029/2003JD004325 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809FN UT WOS:000220622700006 ER PT J AU Read, WG Wu, DL Waters, JW Pumphrey, HC AF Read, WG Wu, DL Waters, JW Pumphrey, HC TI A new 147-56 hPa water vapor product from the UARS Microwave Limb Sounder SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE humidity measurement; remote sensing ID ATMOSPHERE RESEARCH SATELLITE; VALIDATION; STRATOSPHERE; TEMPERATURES; REANALYSES; ABSORPTION AB [1] Measurements of H2O in the tropopause region have been obtained by production of a new data set from the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite (UARS). A modified version of the retrieval scheme used to produce upper tropospheric humidity (UTH) from the MLS 203 GHz radiometer was applied to the MLS 183 GHz radiometer measurements to produce useful H2O data at 147, 121, 100, 83, 68, and 56 hPa. These new data, for the first 18 months of the UARS mission when the MLS 183 GHz radiometer was operational, fill an important "gap'' around 100 hPa where previous MLS H2O data were generally not useful. Characteristics of the new data set are discussed and compared with National Oceanic and Atmospheric Administration (NOAA), Climate Monitoring and Diagnostics Laboratory (CMDL) frost-point hygrometer, and UARS Halogen Occultation Experiment (HALOE) measurements. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Edinburgh, Dept Meteorol, Edinburgh EH9 3JZ, Midlothian, Scotland. RP Read, WG (reprint author), CALTECH, Jet Prop Lab, Mail Stop 183-701,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM bill@mls.jpl.nasa.gov; dwu@mls.jpl.nasa.gov; joe@mls.jpl.nasa.gov; h.c.pumphrey@ed.ac.uk RI Wu, Dong/D-5375-2012 NR 26 TC 19 Z9 19 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 26 PY 2004 VL 109 IS D6 AR D06111 DI 10.1029/2003JD004366 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809FN UT WOS:000220622700007 ER PT J AU Read, WG Wu, DL Waters, JW Pumphrey, HC AF Read, WG Wu, DL Waters, JW Pumphrey, HC TI Dehydration in the tropical tropopause layer: Implications from the UARS Microwave Limb Sounder SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE UARS Microwave Limb Sounder water vapor measurements; dehydration in the tropical tropopause layer; seasonal evolution of water vapor in the upper troposphere/lower stratosphere ID HALOGEN OCCULTATION EXPERIMENT; STRATOSPHERIC WATER-VAPOR; SEASONAL-VARIATIONS; ANNUAL CYCLE; TRANSPORT; SPACE; TEMPERATURES; VALIDATION; HUMIDITY; CIRRUS AB [1] Measurements of H2O from the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite (UARS) are used to investigate the structure of H2O in the near tropopause region and dehydration mechanisms in the tropical tropopause layer (TTL). The new MLS data are consistent with convective input of H2O into the bottom of the TTL followed by slow ascent with a maximum relative amplitude in the seasonal cycle occurring near the tropopause nearly in phase with the tropopause temperature seasonal cycle. The relative amplitude of the seasonal cycle shows a minimum at 121 hPa in the upwelling moist phase. These features are reproduced with the "cold-trap'' dehydration hypothesis. Seasonal maps show wettest tropical 100 hPa H2O colocated with continental convection. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Edinburgh, Dept Meteorol, Edinburgh EH9 3JZ, Midlothian, Scotland. RP Read, WG (reprint author), CALTECH, Jet Prop Lab, Mail Stop 183-701,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM bill@mls.jpl.nasa.gov; joe@mls.jpl.nasa.gov; dwu@mls.jpl.nasa.gov; h.c.pumphrey@ed.ac.uk RI Wu, Dong/D-5375-2012 NR 36 TC 25 Z9 26 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 26 PY 2004 VL 109 IS D6 AR D06110 DI 10.1029/2003JD004056 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809FN UT WOS:000220622700003 ER PT J AU de Viron, O Boy, JP Goosse, H AF de Viron, O Boy, JP Goosse, H TI Geodetic effects of the ocean response to atmospheric forcing in an ocean general circulation model SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article DE Earth-ocean-atmosphere interaction; Earth rotation; gravity ID SEA-ICE MODEL; TOPEX/POSEIDON DATA; POLAR MOTION; NUTATION; VARIABILITY; SENSITIVITY; PRESSURE; LENGTH; EARTH; PARAMETERIZATION AB [1] We have adapted the Coupled Large-scale Ice-Ocean (CLIO) model in order to include atmospheric pressure forcing in addition to the classical atmospheric forcing ( heat and freshwater fluxes and wind stress). We have compared the modeled bottom pressure to in situ bottom pressure measurements and also to another ocean model. We have computed the induced effects on Earth orientation parameters ( polar motion and nutations) and also on Earth time-variable gravity field. We show that the response of the ocean to atmospheric pressure forcing has geodetic consequences well above the precision level and that the response of CLIO seems reasonable with respect to the few data sets we can compare with. We also show that the results obtained from the model improve the modeling of polar motion. C1 Observ Royal Belgique, B-1180 Brussels, Belgium. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Catholic Univ Louvain, Inst Astron & Geophys Georges Lemaitre, B-1348 Louvain, Belgium. RP Observ Royal Belgique, Ave Circulaire 3, B-1180 Brussels, Belgium. EM o.deviron@oma.be; jpboy@eost.u-strasbg.fr; hgs@astr.ucl.ac.be RI de Viron, Olivier/N-6647-2014; Boy, Jean-Paul/E-6677-2017 OI de Viron, Olivier/0000-0003-3112-9686; Boy, Jean-Paul/0000-0003-0259-209X NR 40 TC 8 Z9 8 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAR 26 PY 2004 VL 109 IS B3 AR B03411 DI 10.1029/2003JB002837 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 809GI UT WOS:000220624800003 ER PT J AU Hudon, P Jung, IH Baker, DR AF Hudon, P Jung, IH Baker, DR TI Effect of pressure on liquid-liquid miscibility gaps: A case study of the systems CaO-SiO2, MgO-SiO2, and CaMgSi2O6-SiO2 SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Review DE immiscibility; high pressure; silicate systems ID INDUCED COORDINATION CHANGES; BINARY OXIDE MELTS; QUASI-CHEMICAL MODEL; PHASE-SEPARATION; HIGH-TEMPERATURE; THERMODYNAMIC PROPERTIES; IMMISCIBLE LIQUIDS; SILICATE SYSTEMS; OLDOINYO-LENGAI; IRON METEORITE AB [1] In order to investigate the effects of liquid-liquid phase separation on the igneous evolution of planetary bodies, we investigated immiscibility in the systems CaO-SiO2, MgO-SiO2, and CaMgSi2O6-SiO2 at pressures to 1.5 GPa. Few changes are observed in the size of the miscibility gaps in these systems at 1.0 GPa. The decrease of the stable area of the gaps is mainly due to the increase of the monotectic temperature because the latter closely follows the melting temperature of SiO2 at high pressure. The pressure at which the whole CaO-MgO-SiO2 miscibility gap becomes metastable is estimated to be 1.81 GPa. The thermal and compositional extents of miscibility gaps associated with network-modifier cations (such as Ca2+) do not change significantly with increasing pressure, but the extents are increased for amphoteric cations (such as Mg2+), and the change is more pronounced if the latter have small ionic radii and high ionic potentials. Cations possessing high crystal field stabilization energies produce the largest immiscibility fields at atmospheric pressure, and the passage from the high-spin to the low-spin state with increasing pressure is expected to yield even larger miscibility gaps. Magmas containing substantial amounts of amphoteric cations and cations with high crystal field stabilization energies are therefore potential candidates to develop immiscibility at high pressures. C1 McGill Univ, Dept Earth & Planetary Sci, Montreal, PQ H3A 2A7, Canada. Ecole Polytech, Ctr Res Computat Thermochem, Montreal, PQ H3C 3A7, Canada. RP Hudon, P (reprint author), NASA, Lyndon B Johnson Space Ctr, Astromat Res Off, Mail Code SR,2101 NASA Rd 1, Houston, TX 77058 USA. EM pierre.hudon@jsc.nasa.gov; in-ho.jung@polymtl.ca; donb@geosci.eps.mcgill.ca RI Hudon, Pierre/E-4994-2010 NR 101 TC 6 Z9 6 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAR 26 PY 2004 VL 109 IS B3 AR B03207 DI 10.1029/2003JB002659 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 809GI UT WOS:000220624800001 ER PT J AU Koren, I Kaufman, YJ AF Koren, I Kaufman, YJ TI Direct wind measurements of Saharan dust events from Terra and Aqua satellites SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID AEROSOL; MODEL; VALIDATION; TRANSPORT AB Wind speed and direction, during Saharan dust episodes are calculated by estimating the movement of the dust plume between the morning observations from Terra and the afternoon observations from Aqua by the MODerate resolution Imaging Spectroradiometer ( MODIS). The difference in the position of the dust front ( easily identified both near the dust sources and over the ocean) between the Terra and Aqua observations is used to derive the actual wind field of the dust layer. The analysis is used to estimate the near-surface wind properties needed for dust mobilization in the Bodele depression. Comparison with NCEP reanalysis winds shows that NCEP underestimated by factor 2 the actual speed of the dust front progression near the sources and produced an azimuthal spread, three times wider than the measured one. Over the seashore, with more numerous meteorological observations, the NCEP wind field did match very well the dust measurements. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CNR, Washington, DC 20418 USA. RP Koren, I (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM ilank@climate.gsfc.nasa.gov RI Koren, Ilan/K-1417-2012 OI Koren, Ilan/0000-0001-6759-6265 NR 12 TC 41 Z9 41 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 25 PY 2004 VL 31 IS 6 AR L06122 DI 10.1029/2003GL019338 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 809EY UT WOS:000220621200004 ER PT J AU Hajj, GA Ao, CO Iijima, BA Kuang, D Kursinski, ER Mannucci, AJ Meehan, TK Romans, LJ Juarez, MD Yunck, TP AF Hajj, GA Ao, CO Iijima, BA Kuang, D Kursinski, ER Mannucci, AJ Meehan, TK Romans, LJ Juarez, MD Yunck, TP TI CHAMP and SAC-C atmospheric occultation results and intercomparisons SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE GPS occultations; temperature profiling; CHAMP; SAC-C ID GLOBAL POSITIONING SYSTEM; GPS RADIO OCCULTATION; LOW-EARTH-ORBIT; LOWER TROPOSPHERE; NEUTRAL ATMOSPHERE; PRECISE TRACKING; WATER-VAPOR; SIGNALS; PROPAGATION; INVERSIONS AB [1] The German Challenging Minisatellite Payload (CHAMP) and Argentine Satelite de Aplicaciones Cientificas-C (SAC-C) Earth science missions, launched in 2000, carry a new generation of Global Positioning System (GPS) receivers for radio occultation sounding of the ionosphere and neutral atmosphere. Though the occultation concept for obtaining profiles of atmospheric temperature, pressure, and moisture was proven in 1995 with GPS/MET, concurrent measurements from CHAMP and SAC-C present the first opportunity for a preliminary evaluation of three central claims: (1) GPS soundings are effectively free of instrumental bias and drift; (2) individual temperature profiles are accurate to <0.5 K between similar to 5 and 20 km; and (3) averaged profiles for climate studies can be accurate to <0.1 K. These properties imply that a weak climate trend can be monitored and detected in less than a decade and studied by different instruments at different times with no external calibration. While this detection cannot by itself tell us the source of the climate change, whether natural and anthropogenic, this detection is a prerequisite to answer the more difficult problem of understanding the cause of change. In this paper, these three claims are evaluated by comparing nearby CHAMP and SAC-C profiles. Of nearly 130,000 profiles examined, 212 pairs occurring within 30 min and 200 km of one another were found. Profile pairs agree to <0.86 K (68% confidence interval) and to within 0.1 K in the mean between 5 and 15 km altitude, after removing the expected variability of the atmosphere. If the errors in CHAMP and SAC-C are assumed to be uncorrelated, this implies that individual profiles are precise to <0.6 K between 5 and 15 km. Individual comparisons show closest agreement near the tropopause and display finer resolution than and substantially different temperatures from numerical weather model analyses from the European Centre for Medium-Range Weather Forecasts (ECMWF). Comparisons between CHAMP and SAC-C largely indicate precision; however, several features observed in common, especially near the tropopause, tend also to indicate accuracy. Limitations of previous experiments (e. g., GPS/MET) in probing the lower troposphere have significantly improved with CHAMP and SAC-C, with the majority of profiles (60%) descending to the lowest 0.5 km. This is expected to increase to 90-95% with future system improvements. However, the N-bias problem encountered in GPS/MET is also present in CHAMP and SAC-C, and it is expected to be much reduced once open loop tracking is implemented. Examples are selected to illustrate lower tropospheric sensing, including detection of the planetary boundary layer height. For the first time, such performance is achieved with GPS Antispoofing encryption on. Daily occultations currently number similar to350-400; this is expected to reach over 1000 in the near future, rivaling the number of semidaily radiosonde launches. With several new missions in planning, this may increase tenfold in the next 3-8 years, making GPS sounding a potentially significant input to numerical weather prediction and climate research. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Arizona, Dept Atmospher Sci, Tucson, AZ 85721 USA. RP Hajj, GA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 238-600, Pasadena, CA 91109 USA. EM george.hajj@jpl.nasa.gov; chi.o.ao@jpl.nasa.gov; byron.a.iijima@jpl.nasa.gov; da.kuang@jpl.nasa.gov; kursinski@atmo.arizona.edu; tony.mannucci@jpl.nasa.gov; larry.romans@jpl.nasa.gov; mtj@jpl.nasa.gov; thomas.p.yunck@jpl.nasa.gov RI Mannucci, Anthony/A-1349-2007 OI Mannucci, Anthony/0000-0003-2391-8490 NR 39 TC 199 Z9 203 U1 3 U2 18 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 25 PY 2004 VL 109 IS D6 AR D06109 DI 10.1029/2003JD003909 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809FK UT WOS:000220622400002 ER PT J AU Stajner, I Winslow, N Rood, RB Pawson, S AF Stajner, I Winslow, N Rood, RB Pawson, S TI Monitoring of observation errors in the assimilation of satellite ozone data SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE assimilation; satellite; ozone data ID TRACER-TRANSPORT MODEL; KALMAN FILTER; VALIDATION; TEMPERATURE; PROFILES; SYSTEM; COLUMN; AIRS/AMSU/HSB; ALGORITHM; SOUNDER AB [1] Ozone observations from the Solar Backscatter UltraViolet/2 (SBUV/2) instruments and/or the Earth Probe Total Ozone Mapping Spectrometer (EP TOMS) have been assimilated in near-real time at NASA's Data Assimilation Office (DAO) since January 2000. The ozone data assimilation system was used as a tool for detecting and characterizing changes in the observation errors. The forecast model captures the geophysical variability. A change in the observed-minus-forecast (O-F) residuals, which are defined as differences between the incoming ozone observations and the collocated short-term model forecast, indicates a change in the assimilation system. If the model and the statistical analysis scheme are stable, then it points to a modification in instrument characteristics or a retrieval algorithm. However, sometimes a change in the ozone O-F residuals is caused by differences in the availability of the meteorological observations or modifications in the meteorological assimilation system whose winds are used to drive the ozone transport model. The O-F residuals are routinely produced and monitored in the assimilation process. Using examples from the NOAA 14 and NOAA 16 SBUV/2 instruments, and the EP TOMS, we demonstrate that the monitoring of time series of O-F residual statistics is an effective, sensitive, and robust method for identifying time-dependent changes in the observation-error characteristics of ozone. In addition, the data assimilation system was used to assist in the validation of updated calibration coefficients for the NOAA 14 SBUV/2 instrument. This assimilation-based monitoring work is being extended to ozone data from instruments on new satellites: Environmental satellite (Envisat), Earth Observing System (EOS) Aqua, and EOS Aura. C1 NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. RP Stajner, I (reprint author), Sci Applicat Int Corp, Beltsville, MD USA. EM istajner@gmao.gsfc.nasa.gov; nwinslow@gmao.gsfc.nasa.gov; rrood@gmao.gsfc.nasa.gov; spawson@gmao.gsfc.nasa.gov RI Rood, Richard/C-5611-2008; Stajner, Ivanka/B-5228-2009; Pawson, Steven/I-1865-2014 OI Rood, Richard/0000-0002-2310-4262; Stajner, Ivanka/0000-0001-6103-3939; Pawson, Steven/0000-0003-0200-717X NR 41 TC 23 Z9 25 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 25 PY 2004 VL 109 IS D6 AR D06309 DI 10.1029/2003JD004118 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809FK UT WOS:000220622400003 ER PT J AU Proshutinsky, A Ashik, IM Dvorkin, EN Hakkinen, S Krishfield, RA Peltier, WR AF Proshutinsky, A Ashik, IM Dvorkin, EN Hakkinen, S Krishfield, RA Peltier, WR TI Secular sea level change in the Russian sector of the Arctic Ocean SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article DE Arctic; sea level rise; decadal variability; steric effects; inverted barometer effect; glacial isostatic adjustment ID GLACIAL ISOSTATIC-ADJUSTMENT; ICE-SHEET; VM2 MODEL; RISE; EARTH AB Sea level is a natural integral indicator of climate variability. It reflects changes in practically all dynamic and thermodynamic processes of terrestrial, oceanic, atmospheric, and cryospheric origin. The use of estimates of sea level rise as an indicator of climate change therefore incurs the difficulty that the inferred sea level change is the net result of many individual effects of environmental forcing. Since some of these effects may offset others, the cause of the sea level response to climate change remains somewhat uncertain. This paper is focused on an attempt to provide first-order answers to two questions, namely, what is the rate of sea level change in the Arctic Ocean, and furthermore, what is the role of each of the individual contributing factors to observed Arctic Ocean sea level change? In seeking answers to these questions we have discovered that during the period 1954-1989 the observed sea level over the Russian sector of the Arctic Ocean is rising at a rate of approximately 0.123 cm yr(-1) and that after correction for the process of glacial isostatic adjustment this rate is approximately 0.185 cm yr(-1). There are two major causes of this rise. The first is associated with the steric effect of ocean expansion. This effect is responsible for a contribution of approximately 0.064 cm yr(-1) to the total rate of rise (35%). The second most important factor is related to the ongoing decrease of sea level atmospheric pressure over the Arctic Ocean, which contributes 0.056 cm yr(-1), or approximately 30% of the net positive sea level trend. A third contribution to the sea level increase involves wind action and the increase of cyclonic winds over the Arctic Ocean, which leads to sea level rise at a rate of 0.018 cm yr(-1) or approximately 10% of the total. The combined effect of the sea level rise due to an increase of river runoff and the sea level fall due to a negative trend in precipitation minus evaporation over the ocean is close to 0. For the Russian sector of the Arctic Ocean it therefore appears that approximately 25% of the trend of 0.185 cm yr(-1), a contribution of 0.048 cm yr(-1), may be due to the effect of increasing Arctic Ocean mass. C1 Woods Hole Oceanog Inst, Dept Phys Oceanog, Woods Hole, MA 02543 USA. Arctic & Antarctic Res Inst, St Petersburg 199397, Russia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. RP Proshutinsky, A (reprint author), Woods Hole Oceanog Inst, Dept Phys Oceanog, MS 29,360 Woods Hole Rd, Woods Hole, MA 02543 USA. EM aproshutinsky@whoi.edu RI Peltier, William/A-1102-2008; Hakkinen, Sirpa/E-1461-2012 NR 52 TC 38 Z9 39 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 EI 2169-9291 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAR 25 PY 2004 VL 109 IS C3 AR C03042 DI 10.1029/2003JC002007 PG 19 WC Oceanography SC Oceanography GA 809FT UT WOS:000220623300002 ER PT J AU Uemura, M Kato, T Ishioka, R Tanabe, K Torii, KI Santallo, R Monard, B Markwardt, CB Swank, JH Sault, RJ Macquart, JP Linnolt, M Kiyota, S Stubbings, R Nelson, P Richards, T Bailyn, C West, D Masi, G Miyashita, A Sano, Y Scarmato, T AF Uemura, M Kato, T Ishioka, R Tanabe, K Torii, KI Santallo, R Monard, B Markwardt, CB Swank, JH Sault, RJ Macquart, JP Linnolt, M Kiyota, S Stubbings, R Nelson, P Richards, T Bailyn, C West, D Masi, G Miyashita, A Sano, Y Scarmato, T TI Outburst and post-outburst active phase of the black hole X-ray binary V4641 Sagittarii in 2002 SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN LA English DT Article DE accretion, accretion disks; stars : binaries : close; stars : individual (V4641 Sagittarii) ID QUASI-PERIODIC OSCILLATIONS; XTE J1118+480; GX 339-4; OPTICAL VARIABILITY; GRO J1655-40; ACCRETION; STATE; JET; GRS-1915+105; RXTE AB The black hole X-ray binary V4641 Sgr experienced an outburst in 2002 May, which was detected at X-ray, optical, and radio wavelengths. The outburst lasted for only 6 days, but the object remained active for the next several months. Here, we report on the detailed properties of light curves during the outburst and the post-outburst active phase. We reveal that rapid optical variations of similar to 100 s became more prominent when a thermal flare weakened and the optical spectrum flattened in the I-c, R-c, and V-band regions. In conjunction with the flat spectrum in the radio ran-e, this strongly indicates that the origin of rapid variations is not thermal emission, but synchrotron emission.Just after the outburst, we detected repeated flares at optical and X-ray wavelengths. The optical and X-ray light curves exhibited a strong correlation with the X-rays lagging by about 7 min. The X-ray lag can be understood in terms of a hot region propagating into the inner region of the accretion flow. The short X-ray lag, however, requires modifications of this simple scenario to account for the short propagation time. We also detected high-amplitude rapid variations 50 days after the outburst, which we call optical flashes. During the most prominent optical flash, the object brightened by 1.2 mag only within 30 s. The released energy indicates that the emission source should be at the innermost region of the accretion flow. C1 Kyoto Univ, Fac Sci, Dept Astron, Sakyo Ku, Kyoto 6068502, Japan. Okayama Univ Sci, Fac Informat, Dept Biosphere Geosphere Syst, Okayama 7000005, Japan. RIKEN, Inst Phys & Chem Res, Cosm Radiat Lab, Wako, Saitama 3510198, Japan. So Stars Observ, Tahiti, Fr Polynesia. Bronberg Observ, ZA-0056 Tiegerpoort, South Africa. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Australia Telescope Natl Facil, Narrabri, NSW 2390, Australia. Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. Ctr Balcony Astrophys, VSOLJ, Tsukuba, Ibaraki 3050031, Japan. Woodridge Observ, Eltham, Vic 3095, Australia. Yale Univ, Dept Astron, New Haven, CT 06520 USA. W Skies Observ, Derby, KS 67037 USA. Seikei High Sch, Tokyo 1808633, Japan. VSOLJ, Nayoro, Hokkaido 0960022, Japan. RP Kyoto Univ, Fac Sci, Dept Astron, Sakyo Ku, Kyoto 6068502, Japan. EM uemura@kusastro.kyoto-u.ac.jp RI Macquart, Jean-Pierre/B-5306-2013 NR 52 TC 15 Z9 15 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0004-6264 EI 2053-051X J9 PUBL ASTRON SOC JPN JI Publ. Astron. Soc. Jpn. PD MAR 25 PY 2004 VL 56 IS 1 SI SI BP S61 EP S75 DI 10.1093/pasj/56.sp1.S61 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 809EL UT WOS:000220619900003 ER PT J AU Davis-Street, JE Fesperman, JV Smith, MD Rice, BL Dillon, EL DeKerlegand, DE Gillman, PL AF Davis-Street, JE Fesperman, JV Smith, MD Rice, BL Dillon, EL DeKerlegand, DE Gillman, PL TI Nutritional assessment in a spaceflight analog: 14-d saturation dive SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Enterprise Advisory Serv Inc, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. RI Dillon, Edgar/B-2495-2008 NR 0 TC 0 Z9 0 U1 0 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A882 EP A882 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470700594 ER PT J AU Evans, JM Knapp, CF Stenger, MB Patwardhan, AR Hinghofer-Szalkay, HG Ziegler, MG Moore, FB Pelligra, R AF Evans, JM Knapp, CF Stenger, MB Patwardhan, AR Hinghofer-Szalkay, HG Ziegler, MG Moore, FB Pelligra, R TI Artificial gravity training increases presyncopal orthostatic tolerance SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Univ Kentucky, Wenner Gren Lab, Lexington, KY 40506 USA. Med Univ Graz, A-8010 Graz, Austria. Univ Calif San Diego, Gen Clin Res Ctr, San Diego, CA 92103 USA. NASA, Ames Res Ctr, Human Environm Lab, Mountain View, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A1291 EP A1291 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470702542 ER PT J AU Hayashi, Y Shi, SJ Meck, JV AF Hayashi, Y Shi, SJ Meck, JV TI Ankle arterial pressure predicts orthostatic hypotension before brachial artery pressure SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Univ Texas, Hlth Sci Ctr, Houston, TX 77225 USA. Wyle Labs, Houston, TX USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A1208 EP A1208 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470702148 ER PT J AU Heer, M Baecker, N Boese, A Smith, SM AF Heer, M Baecker, N Boese, A Smith, SM TI High calcium intake does not counteract disuse-induced bone loss SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Inst Aerosp Med, German Aerosp Ctr, D-51170 Cologne, Germany. NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A853 EP A853 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470700455 ER PT J AU Mitchell, BM Waters, WW Meck, JV AF Mitchell, BM Waters, WW Meck, JV TI Fludrocortisone does not attenuate bedrest-induced orthostatic hypotension SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Univ Space Res Assoc, Div Space Life Sci, Houston, TX 77058 USA. Wyle Labs, Cardiovasc Lab, Houston, TX USA. NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A1206 EP A1206 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470702140 ER PT J AU Platts, SH Waters, WW Mitchell, B Meck, JV AF Platts, SH Waters, WW Mitchell, B Meck, JV TI Midodrine prevents post-spaceflight orthostatic intolerance when administered 1 hour before tilt test SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 USRA, Div Space Life Sci, Houston, TX 77058 USA. Wyle Labs, Cardiovasc Lab, Houston, TX USA. USRA, Cardiovasc Lab, Houston, TX USA. NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A1207 EP A1207 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470702144 ER PT J AU Smith, SM Rice, BL Dillon, EL Davis-Street, JE Block, G AF Smith, SM Rice, BL Dillon, EL Davis-Street, JE Block, G TI Assessing dietary intake on the International Space Station using a Food Frequency Questionnaire (FFQ) SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. Enterprise Advisory Sci Inc, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. RI Dillon, Edgar/B-2495-2008; Block, Gladys/E-3304-2010 NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A882 EP A882 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470700593 ER PT J AU Smith, SM Davis-Street, JE Fesperman, JV DeKerlegand, DE Watenpaugh, D Lee, SMC Macias, BR Hargens, AR AF Smith, SM Davis-Street, JE Fesperman, JV DeKerlegand, DE Watenpaugh, D Lee, SMC Macias, BR Hargens, AR TI Treadmill exercise within lower body negative pressure (LBNP): counteracting bed rest-induced bone loss in female subjects SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. Enterprise Advisory Serv Inc, Human Adaptat & Countermeasures Off, Houston, TX USA. Naval Submarine Med Res Lab, Groton, CT USA. Wyle Labs, Human Adaptat & Countermeasures Off, Houston, TX USA. Univ Calif San Diego, Dept Orthopaed, San Diego, CA 92103 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A853 EP A853 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470700454 ER PT J AU Stenger, MB Evans, JM Patwardhan, AR Moore, FB Hinghofer-Szalkay, HG Knapp, CF AF Stenger, MB Evans, JM Patwardhan, AR Moore, FB Hinghofer-Szalkay, HG Knapp, CF TI Mechanisms of increased orthostatic tolerance following artificial gravity training SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Univ Kentucky, Wenner Gren Lab, Lexington, KY 40506 USA. NASA, Ames Res Ctr, Human Environm Lab, Mountain View, CA USA. Med Univ Graz, A-8010 Graz, Austria. NR 0 TC 0 Z9 0 U1 1 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A1296 EP A1296 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470702566 ER PT J AU Strasnick, SL Martinez, DA Manickam, P Grindeland, RE Wade, CE AF Strasnick, SL Martinez, DA Manickam, P Grindeland, RE Wade, CE TI Hindlimb unloading alters gene expression patterns in wound healing ligaments SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 NASA, Ames Res Ctr, Life Sci Res Div, Moffett Field, CA 94035 USA. Univ Houston, Dept Biol & Biochem, Houston, TX USA. RI Martinez, Daniel/A-5825-2008 NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A942 EP A942 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470700870 ER PT J AU Tou, JCL Arnaud, SB Grindeland, R Wade, C AF Tou, JCL Arnaud, SB Grindeland, R Wade, C TI The effect of feeding purified versus chow diet on bone changes induced by hindlimb suspension of female rats SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 NASA, Ames Res Ctr, Div Life Sci, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A918 EP A918 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470700760 ER PT J AU Waters, WW Ziegler, MG Meck, JV AF Waters, WW Ziegler, MG Meck, JV TI Furosemide plus low salt diet models post-spaceflight plasma volume loss and orthostatic hypotension SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Wyle Labs, Cardiovasc Lab, Houston, TX 77058 USA. Univ Calif San Diego, Dept Med, San Diego, CA 92103 USA. NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A1206 EP A1207 PG 2 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470702141 ER PT J AU Zwart, SR Hargens, AR Smith, SM AF Zwart, SR Hargens, AR Smith, SM TI The ratio of animal protein to potassium intake is correlated with markers of bone resorption in ambulatory and bed rest subjects SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. Univ Calif San Diego, Dept Orthopaed, San Diego, CA 92103 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 24 PY 2004 VL 18 IS 5 SU S BP A918 EP A918 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZB UT WOS:000220470700761 ER PT J AU Argus, DF Gross, RS AF Argus, DF Gross, RS TI An estimate of motion between the spin axis and the hotspots over the past century SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CURRENT PLATE VELOCITIES; MANTLE VISCOSITY; EARTHS ROTATION; PERTURBATIONS; ATLANTIC; TRACKS; MODELS; PLUMES; TIME AB Estimates of the motion of the spin axis over the past century either neglect plate motion or are relative to the mean lithosphere. To understand the response of the spin axis to mass changes, it is more useful to estimate spin axis motion relative to the hotspots because the hotspots well represent the solid earth. The hotspots originate in the lower mantle, which comprises 2/3 of the earth's volume. Relative to the lower mantle the plates and the upper mantle move in opposite directions, to a large extent canceling each other out. The mean lithosphere moves quickly relative to the hotspots and poorly represents the solid earth. The spin axis has moved relative to the hotspots over the past century along the 68.4 degreesW meridian at 4.03 milliarcsecond/ yr. This motion is 11degrees counterclockwise of, 0.5 milliarcsecond/ yr faster than, and 25% different than spin axis motion relative to the mean lithosphere. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Argus, DF (reprint author), CALTECH, Jet Prop Lab, Mail Stop 238-600,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM donald.f.argus@jpl.nasa.gov RI Argus, Donald/F-7704-2011 NR 21 TC 18 Z9 18 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 24 PY 2004 VL 31 IS 6 AR L06614 DI 10.1029/2004GL019657 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 809EW UT WOS:000220621000007 ER PT J AU Hashizume, H Liu, WT AF Hashizume, H Liu, WT TI Systematic error of microwave scatterometer wind related to the basin-scale plankton bloom SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SURFACE-FILMS; ATMOSPHERIC STABILITY; RADAR BACKSCATTER; GLOBAL OCEAN; PHYTOPLANKTON; SPEED; REANALYSIS; ACCURACY; COAST AB Chlorophyll-a concentration derived from satellite ocean color sensor are compared with coincident wind speed difference between microwave scatterometer QuikSCAT product and reanalysis product from the National Center for Environmental Prediction over global oceans. The objective is to explore if a natural surface film, which originates in biological productivity, causes the underestimation of surface wind in scatterometer measurement by damping the small capillary wave through the surface tension. The wind speed difference (Reanalysis wind - QuikSCAT wind) is found to correlate positively with chlorophyll-a over the biologically highly productive areas, especially from intra-seasonal to seasonal time scales, indicating the surface film effect. The wind speed difference increases from similar to - 1 m s(-1) to similar to0.5 m s(-1) as chlorophyll-a increases from similar to 0.1 mg m(-3) to similar to3 mg m(-3), which is comparable with the results of previous laboratory experiments with artificial oil. C1 Osaka Prefecture Univ, Dept Aerosp Engn, Sakai, Osaka 5998531, Japan. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Hashizume, H (reprint author), Osaka Prefecture Univ, Dept Aerosp Engn, 1-1 Gakuen Cho, Sakai, Osaka 5998531, Japan. EM zume@aero.osakafu-u.ac.jp NR 28 TC 3 Z9 3 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 24 PY 2004 VL 31 IS 6 AR L06307 DI 10.1029/2003GL018941 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 809EW UT WOS:000220621000003 ER PT J AU Andrews, E Sheridan, PJ Ogren, JA Ferrare, R AF Andrews, E Sheridan, PJ Ogren, JA Ferrare, R TI In situ aerosol profiles over the Southern Great Plains cloud and radiation test bed site: 1. Aerosol optical properties SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE atmospheric aerosol; airborne measurement; in situ measurement ID SINGLE-SCATTERING ALBEDO; MARINE BOUNDARY-LAYER; MID-ATLANTIC COAST; LIGHT-SCATTERING; HUMIDIFICATION FACTORS; TROPOSPHERIC AEROSOL; UNITED-STATES; WATER-VAPOR; DEPTH; BRAZIL AB Aerosol optical properties were measured over the Southern Great Plains (SGP) cloud and radiation test bed site using a light aircraft (Cessna C-172N). The aircraft flew level legs at altitudes between 500 m and 3500 m several times per week over the course of 2 years in order to obtain a statistically representative data set of in situ aerosol vertical profiles. Instrumentation on the aircraft was similar to that at the surface SGP site so that measurements at the surface and aloft could easily be compared. Measured parameters included total light scattering, backscattering, and absorption, while calculated parameters included single-scattering albedo, backscatter fraction, and Angstrom exponent. Statistical plots of aerosol optical properties and their variation in the lower column (0-4000 m) showed that over the course of the 2 years studied, albedo, backscatter fraction, and Angstrom exponent were fairly invariant with altitude (at least up to 1800 m). Despite the vertical consistency the correlation between column average and surface values for single-scattering albedo, backscatter fraction, and Angstrom exponent tended to be quite low, with R-2 ranging from 0.3 to 0.6 and linear regression slopes ranging from 0.2 to 0.6. These results suggest that long-term surface aerosol measurements capture the column aerosol properties but may not be as representative of day-to-day variations in the column. Comparison of aerosol optical depth (AOD) calculated from the vertical profiles with other measurements of AOD made at SGP (i.e., by the Cimel Sun photometer and the multifilter rotating shadowband radiometer (MFRSR)) showed fair correlation (R(2)similar to0.7 Cimel, R(2)similar to0.8 MFRSR), although the aircraft AODs tend to have a consistent offset of -0.04, even after incorporating a correction for supermicrometer aerosol and stratospheric aerosol. C1 Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. NASA, Chem & Dynam Branch, Langley Res Ctr, Hampton, VA 23681 USA. RP Andrews, E (reprint author), Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. EM betsy.andrews@noaa.gov; patrick.sheridan@noaa.gov; john.a.ogren@noaa.gov; r.ferrare@larc.nasa.gov NR 50 TC 45 Z9 47 U1 0 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 24 PY 2004 VL 109 IS D6 AR D06208 DI 10.1029/2003JD004025 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809FI UT WOS:000220622200002 ER PT J AU Yan, XH Pan, JY Jo, YH He, MX Liu, WT Jiang, LD AF Yan, XH Pan, JY Jo, YH He, MX Liu, WT Jiang, LD TI Role of winds in estimation of ocean heat storage anomaly using satellite data SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID PACIFIC WARM POOL; NORTH PACIFIC; ROSSBY WAVES; ALTIMETER DATA; SEA-LEVEL; EL-NINO; TOPEX/POSEIDON; VARIABILITY; GEOSAT; LAYER AB The heat storage anomaly of the upper ocean can be estimated using altimeter data, based on the thermal dynamics equation. In this study, we analyzed both nonthermal and thermal steric height measured by altimetry, and removed nonthermal steric height from altimeter measurements to calculate the heat storage anomaly from thermal steric height alone in the global oceans, but with a focus on the Pacific Ocean. After examining nonthermal steric height (salinity, waves, and wind), we believe that wind stress is a major component to the change in sea surface height. Blended TOPEX/Poseidon and ERS-1/2 altimeter 1degreesx1degrees sea surface height anomaly from January 1993 to October 2000 were used to calculation of the heat storage anomaly. In addition, we used expendable bathythermograph (XBT) data to the global oceans to determine a reference heat storage, from which the altimeter estimation of the heat storage was compared. The wind stress curls, from scatterometer data obtained from January 1993 to October 2000, were used for analyzing the wind effects on sea surface height variation. The correlation coefficients between heat storage from altimeter data (H'(Alt)) and that from the XBT (H'(XBT)) are larger than 0.6 in the global oceans, except in the regions of 20degreesN in the eastern Pacific, the eastern tropical Pacific, the tropical Atlantic, and the western tropical Indian Ocean. The root mean square (RMS) of the differences (H'(Alt)-H'(XBT)) has large values in the Gulf Stream and the Kuroshio Extension regions as well as the eastern and western tropical Pacific, and eastern Indian Ocean. The wind-induced sea surface height variation exhibits strong annual and interannual cycles, so the empirical orthogonal function (EOF) method was employed to extract the cycles. The annual cycle has two modes, whereas the interannual cycle is characterized by El Nino events. Wind stress can affect the estimation of the heat storage through mechanisms derived from quasi-geostrophic and barotropic theory. We calculated the correlation coefficient between the differences (H'(Alt)-H'(XBT)) and wind stress curl. The result shows that El Nino Southern Oscillation (ENSO) related wind stress curl anomalies are responsible for estimating discrepancy in the regions west of South and North America and tropical oceans. The high correlation suggests that in these regions the barotropic and linear theory is the dynamic mechanism underlying the wind effects on heat storage estimation. Furthermore, we focus on baroclinic signal in sea level resulting from Ekman upwelling in the tropical oceans. The effect of wind-forcing has the most important role in sea level change during the 1997-1998 El Nino event. For instance, the heat storage anomaly (Q') due to the strong coastal upwelling off the west coast of Peru closely relates to sea surface temperature (SST), wind-forcing, remnant sea level height anomaly (Deltaeta') after removing the contributions of the heat, salt, and waves to the sea level height, and Ekman depth (D-EK). However, the Q' in the west coast of America and western Pacific warm pool areas did not closely relate to SST, wind-forcing, Deltaeta', and D-EK. C1 Univ Delaware, Grad Coll Marine Studies, Ctr Remote Sensing, Newark, DE 19716 USA. Ocean Univ China, Ocean Remote Sensing Inst, Qingdao, Peoples R China. CALTECH, Jet Prop Lab 300 323, Pasadena, CA 91109 USA. RP Univ Delaware, Grad Coll Marine Studies, Ctr Remote Sensing, 209C Robinson Hall, Newark, DE 19716 USA. EM xiaohai@udel.edu RI Jiang, Lide/G-2041-2010 OI Jiang, Lide/0000-0002-9883-4411 NR 41 TC 4 Z9 4 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 EI 2169-9291 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAR 24 PY 2004 VL 109 IS C3 AR C03041 DI 10.1029/2003JC002202 PG 20 WC Oceanography SC Oceanography GA 809FQ UT WOS:000220623000006 ER PT J AU Tsyganenko, NA Fairfield, DH AF Tsyganenko, NA Fairfield, DH TI Global shape of the magnetotail current sheet as derived from Geotail and Polar data SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID GEOMAGNETIC NEUTRAL SHEET; DAWN-DUSK ASYMMETRY; NEAR-EARTH REGION; DISTANT MAGNETOTAIL; PLASMA SHEET; MAGNETIC-FIELD; SOLAR-WIND; POSITION; MAGNETOSPHERE; DEPENDENCE AB [1] An analytical approximation is developed for the shape of the nightside tail current sheet, representing it as a function of the Earth's dipole tilt angle, solar wind ram pressure, and the interplanetary magnetic field (IMF). The model is based on 5-min average magnetometer data of the Geotail and Polar spacecraft, spanning the periods 1994 - 2002, and 1999 - 2001, respectively. All the magnetospheric data were tagged by concurrent values of the solar wind dynamic pressure and IMF B-y and B-z components, averaged over 30-min intervals immediately preceding the magnetospheric observations. Warping and twisting parameters were calculated by minimizing the number of mismatches between the observed and predicted orientation of the magnetic field on both sides of the model current sheet. The model is valid within the nightside magnetosphere in the range of tailward distances - 50 R-E less than or equal to X-GSM less than or equal to 0. Variations of the solar wind pressure P change the shape of the deformed current sheet in such a way that an increase of P results in a decrease of the magnetotail "hinging distance'' R-H, but increases the magnitude of its transverse warping. The IMF B-z component affects the magnitude of the seasonal/diurnal motion of the current sheet in the north-south direction, and it also controls the degree of the IMF B-y-related twisting, which becomes much larger during the periods with northward IMF B-z. C1 NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RP Tsyganenko, NA (reprint author), NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Code 695, Greenbelt, MD 20771 USA. EM nikolai.tsyganenko@gsfc.nasa.gov; donald.h.fairfield@nasa.gov RI Tsyganenko, Nikolai/J-7377-2012 OI Tsyganenko, Nikolai/0000-0002-5938-1579 NR 23 TC 69 Z9 71 U1 1 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 24 PY 2004 VL 109 IS A3 AR A03218 DI 10.1029/2003JA010062 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 809GP UT WOS:000220625500001 ER PT J AU Dingemans, TJ Picken, SJ Murthy, NS Mark, P StClair, TL Samulski, ET AF Dingemans, TJ Picken, SJ Murthy, NS Mark, P StClair, TL Samulski, ET TI Wholly aromatic ether-imides. Potential materials for n-type semiconductors SO CHEMISTRY OF MATERIALS LA English DT Article ID KETONE-X POLYMERS; LIQUID-CRYSTALS; MODEL COMPOUNDS; POLYIMIDE; POLY; METALLOMESOGENS AB We report on the synthesis and characterization of a series of low molar mass, high aspect ratio ether-imide compounds. All ether-imides were obtained by terminating the appropriate dianhydride, that is, pyromellitic dianhydride (PMDA), 1,4,5,8-naphthalenetetra-carboxylic dianhydride (NDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), and 3,3',4,4'oxydiphthalic dianhydride (ODPA), with three flexible aryl-ether tails of different chain lengths. Increasing the number of meta-substituted aryl-ether units reduces the melt transition temperatures and at the same time increases the solubility of the ether-imides. When the flexibility of the dianhydride moiety increases, the thermal behaviour of the compounds becomes significantly more complex: The BPDA- and ODPA-based compounds form glasses and exhibit multiple crystal phases. Most compounds form isotropic melts upon heating; however, 2,7-bis(-4-phenoxy-phenyl)-benzo[lmn][3,8]phenanthroline-1,3,6,8-tetraone (NDA-n(o)) displays a smectic A (S-A)-type texture when cooled from the isotropic phase, followed by what appears to be a smectic phase with a columnar arrangement of the mesogens inside the layers. Single-crystal X-ray diffraction analysis and cyclic voltammetry experiments indicate that the wholly aromatic ether-imides NDA and BPDA could be excellent candidates for n-type semiconductor applications. C1 NASA, Langley Res Ctr, ICASE Struct & Mat, Hampton, VA 23681 USA. Delft Univ Technol, Fac Sci Appl, NL-2628 BL Delft, Netherlands. Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA. Univ Vermont, Dept Phys, Burlington, VT 05405 USA. RP Dingemans, TJ (reprint author), NASA, Langley Res Ctr, ICASE Struct & Mat, Mail Stop 132C, Hampton, VA 23681 USA. EM t.j.dingemans@lr.tudelft.nl RI Picken, Stephen/D-7033-2012; Dingemans, Theo/E-3532-2017; OI Picken, Stephen/0000-0002-6003-518X NR 28 TC 16 Z9 17 U1 2 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD MAR 23 PY 2004 VL 16 IS 6 BP 966 EP 974 DI 10.1021/cm021723f PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 804MZ UT WOS:000220304100005 ER PT J AU Baer, LA Plaut, K Wade, CE Ronca, AE AF Baer, LA Plaut, K Wade, CE Ronca, AE TI Hypergravity effects on prenatal development: Potential relations to fetal programming SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 NASA, Ames Res Ctr, Div Life Sci, Moffett Field, CA 94035 USA. Univ Vermont, Burlington, VT 05405 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 23 PY 2004 VL 18 IS 4 SU S BP A758 EP A759 PG 2 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZA UT WOS:000220470603636 ER PT J AU Eckardt, JM Baer, LA Corcoran, ML Daunton, NG Wade, CE AF Eckardt, JM Baer, LA Corcoran, ML Daunton, NG Wade, CE TI Hypergravity effects on body mass reduction between species, strain, gender and age of rodents SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 23 PY 2004 VL 18 IS 4 SU S BP A758 EP A758 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZA UT WOS:000220470603635 ER PT J AU Heer, M Boese, A Baecker, N Zittermann, A Smith, SM AF Heer, M Boese, A Baecker, N Zittermann, A Smith, SM TI Moderate hypocaloric nutrition does not exacerbate bone resorption during bed rest SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 DLR, German Aerosp Ctr, Inst Aerosp Med, D-51170 Cologne, Germany. Ctr Heart, Inst Aerosp Med, Bad Oeynhausen, Germany. NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 23 PY 2004 VL 18 IS 4 SU S BP A756 EP A756 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZA UT WOS:000220470603624 ER PT J AU Hudson, EK Spicer, K Gonda, SR AF Hudson, EK Spicer, K Gonda, SR TI The culture of baby hamster kidney cells in the NASA designed perfused hydrodynamic focusing bioreactor SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Univ Space Res Assoc, NASA, JSC, Houston, TX 77058 USA. Wyle Labs, Houston, TX USA. NASA, Lyndon B Johnson Space Ctr, Biol Syst Off, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 23 PY 2004 VL 18 IS 4 SU S BP A757 EP A757 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZA UT WOS:000220470603631 ER PT J AU Milbury, PE Doman, G Pelligra, R Matson, WR AF Milbury, PE Doman, G Pelligra, R Matson, WR TI Oxidative stress in chronically brain injured children evidenced by metabolic pattern analysis SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 ESA Inc, Chelmsford, MA USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Inst Achievement Human Potential, Philadelphia, PA USA. Tufts Univ, Human Nutr Res Ctr Aging, Boston, MA 02111 USA. NR 0 TC 0 Z9 0 U1 0 U2 3 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 23 PY 2004 VL 18 IS 4 SU S BP A139 EP A140 PG 2 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZA UT WOS:000220470600676 ER PT J AU Ronca, AE Baer, LA Wade, CE Conway, GC AF Ronca, AE Baer, LA Wade, CE Conway, GC TI Labor contractions augment c-fos expression in newborn rat brain SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 NASA, Ames Res Ctr, Div Life Sci, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 23 PY 2004 VL 18 IS 4 SU S BP A685 EP A686 PG 2 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZA UT WOS:000220470603288 ER PT J AU Shi, SJ South, DA Meck, JV AF Shi, SJ South, DA Meck, JV TI Fludrocortisone protects plasma volume, but not orthostatic tolerance in astronauts after spaceflight SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Wyle Labs, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 23 PY 2004 VL 18 IS 4 SU S BP A755 EP A755 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZA UT WOS:000220470603621 ER PT J AU Wade, CE Baer, LA Fuller, PA Stein, TP Grindeland, RE Fuller, CA AF Wade, CE Baer, LA Fuller, PA Stein, TP Grindeland, RE Fuller, CA TI Energy balance in mature male rats hind limb suspended for 90 days SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 NASA, Ames Res Ctr, Div Life Sci, Moffett Field, CA 94035 USA. Univ Calif Davis, Davis, CA 95616 USA. UMDNJ, Stratford, NJ USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 23 PY 2004 VL 18 IS 4 SU S BP A758 EP A758 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZA UT WOS:000220470603634 ER PT J AU Zakrzewska, EW Lintault, L Maple, R Mulvey, T Coughlan, K Roberts, G Baer, L Ronca, A Wade, C Plant, K AF Zakrzewska, EW Lintault, L Maple, R Mulvey, T Coughlan, K Roberts, G Baer, L Ronca, A Wade, C Plant, K TI Effects of 2-g gravity on mammary, liver and adipose metabolism in periparturient rats SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2004 Meeting CY APR 17-21, 2004 CL Washington, DC C1 Univ Vermont, Dept Anim Sci, Burlington, VT 05405 USA. NASA, Ames Res Ctr, Div Life Sci, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 23 PY 2004 VL 18 IS 4 SU S BP A756 EP A757 PG 2 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 806ZA UT WOS:000220470603627 ER PT J AU Katsanos, D Lagouvardos, K Kotroni, V Huffmann, GJ AF Katsanos, D Lagouvardos, K Kotroni, V Huffmann, GJ TI Statistical evaluation of MPA-RT high-resolution precipitation estimates from satellite platforms over the central and eastern Mediterranean SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID RAINFALL AB A statistical verification of satellite precipitation estimates has been conducted for a one year period over the Central and Eastern Mediterranean. The NASA real-time Multi-satellite Precipitation Analysis (MPA-RT) data are verified against 73 raingauge data. The verification aims to assess the skill of these satellite estimates to detect rainy areas and to give information on the accumulated precipitation errors. The results show almost unbiased results for the low and medium precipitation thresholds, especially during the wet period of the year. At higher accumulation thresholds, the satellite data overestimate the rain events compared to the raingauges, especially during the dry period of the year, when the major part of precipitation is produced by isolated thunderstorms. Moreover the analysis showed that for the high precipitation amounts and during the whole period the probability of detection is quite low and the false alarm ratio is high (reaching similar to85% during the dry period). C1 Natl Observ Athens, Natl Inst Environm Res & Sustainable Dev, Athens 15236, Greece. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Katsanos, D (reprint author), Natl Observ Athens, Natl Inst Environm Res & Sustainable Dev, Lofos Koufou, Athens 15236, Greece. EM lagouvar@galaxy.meteo.noa.gr RI Kotroni, Vassiliki/D-5336-2014; Lagouvardos, Konstantinos/D-5683-2014; Huffman, George/F-4494-2014; Katsanos, Dimitrios/N-7222-2014 OI Huffman, George/0000-0003-3858-8308; Katsanos, Dimitrios/0000-0002-1969-7982 NR 5 TC 20 Z9 20 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 23 PY 2004 VL 31 IS 6 AR L06116 DI 10.1029/2003GL019142 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 809EV UT WOS:000220620900006 ER PT J AU Tabazadeh, A Yokelson, RJ Singh, HB Hobbs, PV Crawford, JH Iraci, LT AF Tabazadeh, A Yokelson, RJ Singh, HB Hobbs, PV Crawford, JH Iraci, LT TI Heterogeneous chemistry involving methanol in tropospheric clouds SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TRANSFORM INFRARED-SPECTROSCOPY; ORGANIC-COMPOUNDS; METHYL NITRITE; ACETIC-ACID; TRACE GAS; AEROSOL; ADSORPTION; PARTICLES; DROPLETS; AFRICA AB In this report we analyze airborne measurements to suggest that methanol in biomass burning smoke is lost heterogeneously in clouds. When a smoke plume intersected a cumulus cloud during the SAFARI 2000 field project, the observed methanol gas phase concentration rapidly declined. Current understanding of gas and aqueous phase chemistry cannot explain the loss of methanol documented by these measurements. Two plausible heterogeneous reactions are proposed to explain the observed simultaneous loss and production of methanol and formaldehyde, respectively. If the rapid heterogeneous processing of methanol, seen in a cloud impacted by smoke, occurs in more pristine clouds, it could affect the oxidizing capacity of the troposphere on a global scale. C1 NASA, Ames Res Ctr, Div Earth Sci, Moffett Field, CA 94035 USA. Univ Montana, Dept Chem, Missoula, MT 59812 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. NASA, Langley Res Ctr, Div Earth Sci, Hampton, VA 23681 USA. RP Tabazadeh, A (reprint author), NASA, Ames Res Ctr, Div Earth Sci, Moffett Field, CA 94035 USA. EM atabazadeh@mail.arc.nasa.gov RI Yokelson, Robert/C-9971-2011; Crawford, James/L-6632-2013 OI Yokelson, Robert/0000-0002-8415-6808; Crawford, James/0000-0002-6982-0934 NR 23 TC 22 Z9 23 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 23 PY 2004 VL 31 IS 6 AR L06114 DI 10.1029/2003GL018775 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 809EV UT WOS:000220620900002 ER PT J AU Livesey, NJ Fromm, MD Waters, JW Manney, GL Santee, ML Read, WG AF Livesey, NJ Fromm, MD Waters, JW Manney, GL Santee, ML Read, WG TI Enhancements in lower stratospheric CH3CN observed by the upper atmosphere research satellite microwave limb sounder following boreal forest fires SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE methyl cyanide; biomass burning; convective events ID ACETONITRILE; TROPOSPHERE; EMISSION; SMOKE; OCEAN AB [1] On 25 August 1992, the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite observed a significant enhancement in the abundance of lower stratospheric methyl cyanide (CH3CN) at 100 - 68 hPa ( similar to 16 - 19 km altitude) in a small region off the east coast of Florida. The enhancement was seen to decay and move generally westward over similar to 6 days. Concentrations up to similar to 1500 parts per trillion by volume (pptv) were observed, compared to a typical stratospheric background level of 30 pptv. Aerosol index data from the Nimbus 7 Total Ozone Mapping Spectrometer (TOMS) instrument, together with trajectory calculations, provide strong evidence that the enhancement arose from the stratospheric injection, associated with strong thunderstorms, of tropospheric air with high CH3CN concentrations, originating in regions of extensive forest fire activity in Idaho ( not observed by MLS in this period because of orbital geometry). After being lofted into the lower stratosphere, this air was advected into the regions observed by MLS and subsequently dispersed. These MLS enhanced CH3CN observations add to the growing body of evidence for the occurrence of such episodic injections of tropospheric air into the stratosphere. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Computat Phys Inc, Springfield, VA USA. New Mexico Highlands Univ, Las Vegas, NV USA. RP Livesey, NJ (reprint author), CALTECH, Jet Prop Lab, Mail Stop 183-701,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM livesey@mls.jpl.nasa.gov RI Fromm, Michael/F-4639-2010 NR 17 TC 33 Z9 33 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 23 PY 2004 VL 109 IS D6 AR D06308 DI 10.1029/2003JD004055 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809FG UT WOS:000220622000003 ER PT J AU Drouin, BJ Fry, JL Miller, CE AF Drouin, BJ Fry, JL Miller, CE TI Rotational spectrum of cis-cis HOONO SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PEROXYNITROUS ACID HOONO; NITRIC-ACID; INFRARED-ABSORPTION; SOLID ARGON; GAS-PHASE; OH+NO2+M; SPECTROSCOPY; TEMPERATURE; PHOTOLYSIS; DIOXIDE AB The pure rotational spectrum of cis-cis peroxynitrous acid, HOONO, has been observed. Over 220 transitions, sampling states up to J(')=67 and K-a(')=31, have been fitted with an rms uncertainty of 48.4 kHz. The experimentally determined rotational constants agree well with ab initio values for the cis-cis conformer, a five-membered ring formed by intramolecular hydrogen bonding. The small, positive inertial defect Delta=0.075667(60) amu A(2) and lack of any observable torsional splittings in the spectrum indicate that cis-cis HOONO exists in a well-defined planar structure at room temperature. (C) 2004 American Institute of Physics. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Dept Chem, Pasadena, CA 91125 USA. RP Drouin, BJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 30 TC 10 Z9 10 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 22 PY 2004 VL 120 IS 12 BP 5505 EP 5508 DI 10.1063/1.1687311 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 802SK UT WOS:000220183000002 PM 15267425 ER PT J AU Harstad, KG Bellan, J AF Harstad, KG Bellan, J TI Mixing rules for multicomponent mixture mass diffusion coefficients and thermal diffusion factors SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LENNARD-JONES LIQUIDS; MOLECULAR-DYNAMICS; TRANSPORT; COMBUSTION; SYSTEMS; SORET; AIR AB Mixing rules are derived for mass diffusion coefficient and thermal diffusion factor matrices by developing compatibility conditions between the fluid mixture equations obtained from nonequilibrium thermodynamics and Grad's 13-moment kinetic theory. The mixing rules are shown to be in terms of the species mole fractions and binary processes. In particular, the thermal diffusion factors for binary mixtures obtained by the Chapman-Enskog expansion procedure are suitably generalized for many-component mixtures. Some practical aspects of the results are discussed including the utilization of these mixing rules for high pressure situations. (C) 2004 American Institute of Physics. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Harstad, KG (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 22 TC 12 Z9 12 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 22 PY 2004 VL 120 IS 12 BP 5664 EP 5673 DI 10.1063/1.1650296 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 802SK UT WOS:000220183000021 PM 15267444 ER PT J AU Casper, J Farassat, F AF Casper, J Farassat, F TI Broadband trailing edge noise predictions in the time domain SO JOURNAL OF SOUND AND VIBRATION LA English DT Article ID LOW MACH NUMBERS; PRESSURE FIELD; BOUNDARY-LAYER; AIRFOIL; FLOWS; SCATTERING AB A recently developed analytic result in acoustics, "Formulation 1B," is used to compute broadband trailing edge noise from an unsteady surface pressure distribution on a thin airfoil in the time domain. This formulation is a new solution of the Ffowcs Williams-Hawkings equation with the loading source term, and has been shown in previous research to provide time domain predictions of broadband noise that are in excellent agreement with experimental results. Furthermore, this formulation lends itself readily to rotating reference frames and statistical analysis of broadband trailing edge noise. In the present work, Formulation 1B is used to calculate the farfield noise radiated from the trailing edge of a NACA 0012 airfoil in a low Mach number flow, using both analytical and experimental data on the airfoil surface. The acoustic predictions are compared with analytical results and experimental measurements that are available in the literature. Good agreement between predictions and measurements is obtained. (C) 2003 Elsevier Ltd. All rights reserved. C1 NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Aeroacoust Branch, Hampton, VA 23681 USA. RP Casper, J (reprint author), NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Mail Stop 128, Hampton, VA 23681 USA. EM jay.h.casper@nasa.gov; ferri.farassat@nasa.gov NR 26 TC 15 Z9 15 U1 0 U2 2 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X EI 1095-8568 J9 J SOUND VIB JI J. Sound Vibr. PD MAR 22 PY 2004 VL 271 IS 1-2 BP 159 EP 176 DI 10.1016/S0022-460X(03)00367-5 PG 18 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 800LX UT WOS:000220030900010 ER PT J AU Cropper, M Soria, R Mushotzky, RF Wu, K Markwardt, CB Pakull, M AF Cropper, M Soria, R Mushotzky, RF Wu, K Markwardt, CB Pakull, M TI Probable intermediate-mass black holes in NGC 4559: XMM-Newton spectral and timing constraints SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; black hole physics; galaxies : individual : NGC 4559; X-rays : galaxies; X-rays : stars ID X-RAY SOURCES; EXTRAGALACTIC DISTANCE SCALE; NEARBY SPIRAL GALAXIES; TELESCOPE KEY PROJECT; CHANDRA OBSERVATIONS; ACCRETION DISKS; GALACTIC NUCLEI; CYGNUS X-1; LUMINOSITY; EMISSION AB We have examined X-ray and optical observations of two ultraluminous X-ray sources, X7 and X10 in NGC 4559, using XMM-Newton, Chandra and the Hubble Space Telescope (HST). The ultraviolet/X-ray luminosity of X7 exceeds 2.1 x 10(40) erg s(-1) in the XMM-Newton observation, and that of X10 is > 1.3 x 10(40) erg s(-1). X7 has both thermal and power-law spectral components, The characteristic temperature of the thermal component is 0.12 keV. The power-law components in the two sources both have slopes with photon index similar or equal to2.1. A timing analysis of X7 indicates a break frequency at 28 MHz in the power spectrum, while that for X10 is consistent with an unbroken power law. The luminosity of the blackbody component in the X-ray spectrum of X7 and the nature of its time-variability provides evidence that this object is an intermediate-mass black hole accreting at sub-Eddington rates, but other scenarios which require high advection efficiencies from a hollowed-out disc might be possible. The emission from X10 can be characterized by a single power-law. This source can be interpreted either as an intermediate-mass black hole, or as a stellar mass black hole with relativistically beamed Comptonized emission. There are four optical counterparts in the error circle of X7. No counterparts are evident in the error circle for X10. C1 UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20770 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Observ Astron, F-67000 Strasbourg, France. RP UCL, Mullard Space Sci Lab, Holmbury St Mary, Dorking RH5 6NT, Surrey, England. EM msc@mssl.ucl.ac.uk RI Cropper, Mark/C-1574-2008 NR 79 TC 77 Z9 77 U1 0 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 EI 1365-2966 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAR 21 PY 2004 VL 349 IS 1 BP 39 EP 51 DI 10.1111/j.1365-2966.2004.07480.x PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 802GT UT WOS:000220152700008 ER PT J AU Page, KL Turner, MJL Done, C O'Brien, PT Reeves, JN Sembay, S Stuhlinger, M AF Page, KL Turner, MJL Done, C O'Brien, PT Reeves, JN Sembay, S Stuhlinger, M TI XMM-Newton observations of 3C 273 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : active; galaxies : individual : 3C 273; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; X-RAY-EMISSION; RELATIVISTIC ACCRETION DISK; QUASAR 3C 273; SPECTRAL VARIABILITY; LUMINOSITY; GALAXIES; ASCA; MCG-6-30-15; NGC-5128 AB A series of nine XMM-Newton observations of the radio-loud quasar 3C 273 are presented, concentrating mainly on the soft excess. Although most of the individual observations do not show evidence for iron emission, co-adding them reveals a weak, broad line (EW similar to56 eV). The soft excess component is found to vary, confirming previous work, and can be well fitted with multiple blackbody components, with temperatures ranging between similar to40 and similar to330 eV, together with a power law. Alternatively, a Comptonization model also provides a good fit, with a mean electron temperature of similar to350 eV, although this value is higher when the soft excess is more luminous over the 0.5-10 keV energy band. In the reflection grating spectrometer spectrum of 3C 273, a strong detection of the O VII Healpha absorption line at zero redshift is made; this may originate in warm gas in the local intergalactic medium, consistent with the findings of both Fang, Sembach & Canizares and Rasmussen, Kahn Paerels. C1 Univ Leicester, Dept Phys & Astron, Xray & Observat Astron Grp, Leicester LE1 7RH, Leics, England. Univ Durham, Dept Phys, Durham DH1 3LE, England. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Inst Astron & Astrophys Astron, D-72076 Tubingen, Germany. RP Page, KL (reprint author), Univ Leicester, Dept Phys & Astron, Xray & Observat Astron Grp, Leicester LE1 7RH, Leics, England. EM kpa@star.le.ac.uk RI done, chris/D-4605-2016 OI done, chris/0000-0002-1065-7239 NR 47 TC 27 Z9 27 U1 0 U2 0 PU BLACKWELL PUBLISHING LTD PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAR 21 PY 2004 VL 349 IS 1 BP 57 EP 67 DI 10.1111/j.1365-2966.2004.07499.x PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 802GT UT WOS:000220152700010 ER PT J AU Inam, SC Baykal, A Scott, DM Finger, M Swank, J AF Inam, SC Baykal, A Scott, DM Finger, M Swank, J TI X-ray flux related timing and spectral features of 2S 1417-62 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; stars : emission-line, Be; stars : neutron; X-rays : binaries; X-rays : individual : 2S 1417-62 ID PULSE FREQUENCY CHANGES; TRANSIENT; ACCRETION; EMISSION; STARS; ATMOSPHERES; PERFORMANCE; PULSATIONS; LUMINOSITY; DISCOVERY AB Rossi X-ray Timing Explorer (RXTE) observations of the X-ray transient pulsar 2S 1417-62 between 1999 November and 2000 August with a total exposure of similar to394 ks have been analysed. Observations include a main outburst followed by a series of mini outbursts. Changes in pulse morphology and pulse fraction were found to be related to the changes in X-ray flux. Particularly low X-ray flux regions were found to have significantly lower pulse fractions with different pulse morphologies. The 3-60 keV Proportional Counter Array (PCA) High-Energy X-ray Timing Experiment (HEXTE) main outburst spectrum was modelled with an absorbed power-law model with high-energy cut-off and a Gaussian iron line complex feature. Using the same spectral model, individual 3-20 keV PCA spectra were found to be softer and less absorbed in low X-ray flux regions between outbursts. Spectral studies showed that hydrogen column density was correlated, and the power-law index was anticorrelated with the 3-20 keV X-ray flux. X-ray flux related spectral and timing features in 2S 1417 62, except for low X-ray flux regions, were interpreted as a sign of disc accretion with a similar accretion geometry with a varying mass accretion rate ((M)over dot), whereas spectral and timing features of the low X-ray flux regions were interpreted as a sign of possible temporary accretion geometry change prior to the next periastron where (M)over dot increases again to restore the original accretion geometry. C1 Middle E Tech Univ, Dept Phys, TR-06531 Ankara, Turkey. Natl Space Sci & Technol Ctr, Huntsville, AL 35805 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Middle E Tech Univ, Dept Phys, TR-06531 Ankara, Turkey. EM scinam@metu.edu.tr RI Swank, Jean/F-2693-2012 NR 35 TC 11 Z9 11 U1 0 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 EI 1365-2966 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAR 21 PY 2004 VL 349 IS 1 BP 173 EP 180 DI 10.1111/j.1365-2966.2004.07478.x PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 802GT UT WOS:000220152700020 ER PT J AU Bowden, M Taylor, AN Ganga, KM Ade, PAR Bock, JJ Cahill, G Carlstrom, JE Church, SE Gear, WK Hinderks, JR Hu, W Keating, BG Kovac, J Lange, AE Leitch, EM Maffei, B Mallie, OE Melhuish, SJ Murphy, JA Pisano, G Piccirillo, L Pryke, C Rusholme, BA O'Sullivan, C Thompson, K AF Bowden, M Taylor, AN Ganga, KM Ade, PAR Bock, JJ Cahill, G Carlstrom, JE Church, SE Gear, WK Hinderks, JR Hu, W Keating, BG Kovac, J Lange, AE Leitch, EM Maffei, B Mallie, OE Melhuish, SJ Murphy, JA Pisano, G Piccirillo, L Pryke, C Rusholme, BA O'Sullivan, C Thompson, K TI Scientific optimization of a ground-based CMB polarization experiment SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE polarization; methods : observational; techniques : polarimetric; cosmic microwave background; cosmological parameters ID PROBE WMAP OBSERVATIONS; MICROWAVE BACKGROUND-RADIATION; COSMOLOGICAL PARAMETERS; COMPONENT SEPARATION; POWER SPECTRUM; EMISSION; DASI AB We investigate the science goals achievable with the upcoming generation of ground-based cosmic microwave background polarization experiments, focusing on one particular experiment, QUaD [QUEST (Q and U Extragalactic Submillimetre Telescope) and DASI (Degree Angular Scale Interferometer)], a proposed bolometric polarimeter operating from the South Pole. We calculate the optimal sky coverage for this experiment, including the effects of foregrounds and gravitational lensing. We find that an E-mode measurement will be sample-limited, whereas a B-mode measurement will be detector-noise- limited. We conclude that a 300 deg(2) survey is an optimal compromise for a 2-yr experiment to measure both E and B modes, and that a groundbased polarization experiment can make an important contribution to B-mode surveys. QUaD can make a high significance measurement of the acoustic peaks in the E-mode spectrum, over a multipole range of 25 < l < 2500, and will be able to detect the gravitational lensing signal in the B-mode spectrum. Such an experiment could also directly detect the gravitational wave component of the B-mode spectrum if the amplitude of the signal is close to current upper limits. We also investigate how QUaD can improve constraints on the cosmological parameters. We estimate that combining two years of QUaD data with the 4-yr Wilkinson Microwave Anisotropy Probe (WMAP) data can improve constraints on Omega(b)h(2), Omega(m)h(2), h, r and n(s) by a factor of 2. If the foreground contamination can be reduced, the measurement of r can be improved by up to a factor of 6 over that obtainable from WMAP alone. These improved accuracies will place strong constraints on the potential of the inflaton field. C1 Cardiff Univ, Dept Phys & Astron, Cardiff CF24 3YB, S Glam, Wales. Univ Edinburgh, Royal Observ, Inst Astron, Edinburgh EH9 3HJ, Midlothian, Scotland. CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. Natl Univ Ireland, Expt Phys Dept, Maynooth, Kildare, Ireland. Univ Chicago, Enrico Fermi Inst, Dept Phys, Dept Astron & Astrophys, Chicago, IL 60637 USA. RP Cardiff Univ, Dept Phys & Astron, POB 913, Cardiff CF24 3YB, S Glam, Wales. EM Melanie.Bowden@astro.cf.ac.uk; ant@roe.ac.uk; kmg@ipac.caltech.edu RI Melhuish, Simon/B-1299-2016 OI Melhuish, Simon/0000-0001-8725-4991 NR 39 TC 38 Z9 38 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 EI 1365-2966 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAR 21 PY 2004 VL 349 IS 1 BP 321 EP 335 DI 10.1111/j.1365-2966.2004.07506.x PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 802GT UT WOS:000220152700034 ER PT J AU Sun, WB Loeb, NG Videen, G Fu, Q AF Sun, WB Loeb, NG Videen, G Fu, Q TI Examination of surface roughness on light scattering by long ice columns by use of a two-dimensional finite-difference time-domain algorithm SO APPLIED OPTICS LA English DT Article ID GAUSSIAN PARTICLES; MUELLER MATRIX; GRAINS; CRYSTALS; APPROXIMATION; POLARIZATION; ABSORPTION; FIBER AB Natural particles such as ice crystals in cirrus clouds generally are not pristine but have additional microroughness on their surfaces. A two-dimensional finite-difference time-domain (FDTD) program with a perfectly matched layer absorbing boundary condition is developed to calculate the effect of surface roughness on light scattering by long ice columns. When we use a spatial cell size of 1/120 incident wavelength for ice circular cylinders with size parameters of 6 and 24 at wavelengths of 0.55 and 10.8 mum, respectively, the errors in the FDTD results in the extinction, scattering, and absorption efficiencies are smaller than similar to0.5%. The errors in the FDTD results in the asymmetry factor are smaller than similar to0.05%. The errors in the FDTD results in the phase-matrix elements are smaller than similar to5%. By adding a pseudorandom change as great as 10% of the radius of a cylinder, we calculate the scattering properties of randomly oriented rough-surfaced ice columns. We conclude that, although the effect of small surface roughness on light scattering is negligible, the scattering phase-matrix elements change significantly for particles with large surface roughness. The roughness on the particle surface can make the conventional phase function smooth. The most significant effect of the surface roughness is the decay of polarization of the scattered light. (C) 2004 Optical Society of America. C1 Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. USA, Res Lab, Adelphi, MD 20783 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. RP Sun, WB (reprint author), NASA, Langley Res Ctr, Mail Stop 420, Hampton, VA 23681 USA. EM w.sun@larc.nasa.gov NR 22 TC 24 Z9 24 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD MAR 20 PY 2004 VL 43 IS 9 BP 1957 EP 1964 DI 10.1364/AO.43.001957 PG 8 WC Optics SC Optics GA 805JK UT WOS:000220362400025 PM 15065727 ER PT J AU Yaqoob, T Padmanabhan, U AF Yaqoob, T Padmanabhan, U TI The cores of the FeK lines in Seyfert 1 galaxies observed by the Chandra High Energy Grating SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; galaxies : active; galaxies : Seyfert; line : profiles; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; RESOLUTION X-RAY; XMM-NEWTON; K-ALPHA; IONIZED-GAS; ASCA OBSERVATIONS; IRON LINES; BLACK-HOLE; SPECTROSCOPY; MCG-6-30-15 AB We report on the results of 18 observations of the core, or peak, of the Fe Kalpha emission line at similar to6.4 keV in 15 Seyfert 1 galaxies using the Chandra High Energy Grating (HEG). These data afford the highest precision measurements of the peak energy of the Fe Kalpha line and the highest spectral resolution measurements of the width of the core of the line to date. We were able to measure the peak energy in 17 data sets, and, excluding a very deep observation of NGC 3783, we obtained a weighted mean of 6: 404 +/- 0.005 keV. In all 15 sources the two-parameter, 99% confidence errors on the line peak energy do not exclude fluorescent Kalpha line emission from Fe I, although two sources (Mrk 509 and 3C 120) stand out as very likely being dominated by Kalpha emission from Fe XVII or so. We were able to measure the line core width in 14 data sets and obtained a weighted mean of 2380 +/- 760 km s(-1) FWHM ( excluding the NGC 3783 deep exposure), a little larger than the instrument resolution (similar to1860 km s(-1) FWHM). However, there is evidence of underlying broad-line emission in at least four sources. In fact, the width of the peak varies widely from source to source and may in general have a contribution from the outer parts of an accretion disk and more distant matter. For the disk contribution to also peak at 6.4 keV requires greater line emissivity at hundreds of gravitational radii than has been deduced from previous studies of the Fe Kalpha line. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. NASA, Goddard Space Flight Ctr, High Energy Phys Lab, Greenbelt, MD 20771 USA. RP Yaqoob, T (reprint author), Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. NR 40 TC 113 Z9 113 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2004 VL 604 IS 1 BP 63 EP 73 DI 10.1086/381731 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LU UT WOS:000220301000005 ER PT J AU Peeters, E Allamandola, LJ Bauschlicher, CW Hudgins, DM Sandford, SA Tielens, AGGM AF Peeters, E Allamandola, LJ Bauschlicher, CW Hudgins, DM Sandford, SA Tielens, AGGM TI Deuterated interstellar polycyclic aromatic hydrocarbons SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrochemistry; infrared : ISM; ISM : abundances; ISM : molecules; line : identification; techniques : spectroscopic ID INTERPLANETARY DUST PARTICLES; INFRARED-EMISSION SPECTRA; PAH MOLECULES; PERDEUTERATED NAPHTHALENE; DEUTERIUM ENRICHMENT; MU-M; SPECTROSCOPY; TEMPERATURE; CARBON; BANDS AB We report infrared spectral evidence of deuterated interstellar polycyclic aromatic hydrocarbons (PAHs). Two bands are detected in the infrared emission from the ionization bar in Orion at 4.4 and 4.65 mum. The one at 4.65 mum is present at the 4.4 sigma level, while the one at 4.4 mum is more tentative, with a sigma equal to 1.9. An emission band at 4.65 mum is also detected in the infrared emission from M17 by Verstraete and coworkers at the 4.4 sigma level. These wavelengths are highly characteristic of C-D stretching modes of deuterated PAHs and fall in a featureless region of the interstellar spectrum. The IR spectroscopic properties of deuterated PAHs are summarized, and an estimate of the deuterium fractionation between the aromatic and aliphatic carbons associated with the PAHs is given. High deuterium fractionation is implied; this is discussed in terms of interstellar PAH fractionation mechanisms. C1 Univ Groningen, Kapteyn Astron Inst, SRON, Natl Inst Space Res, NL-9700 AV Groningen, Netherlands. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Peeters, E (reprint author), Univ Groningen, Kapteyn Astron Inst, SRON, Natl Inst Space Res, POB 800, NL-9700 AV Groningen, Netherlands. EM epeeters@mail.arc.nasa.gov; lallamandola@mail.arc.nasa.gov; cbauschlicher@mail.arc.nasa.gov; dhudgins@mail.arc.nasa.gov; ssandford@mail.arc.nasa.gov; tielens@astro.rug.nl NR 47 TC 40 Z9 40 U1 1 U2 5 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2004 VL 604 IS 1 BP 252 EP 257 DI 10.1086/381866 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LU UT WOS:000220301000020 ER PT J AU Chatterjee, S Cordes, JM Vlemmings, WHT Arzoumanian, Z Goss, WM Lazio, TJW AF Chatterjee, S Cordes, JM Vlemmings, WHT Arzoumanian, Z Goss, WM Lazio, TJW TI Pulsar parallaxes at 5 GHz with the very long baseline array SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrometry; pulsars : individual (PSR B0355+54; PSR B1929+10); stars : kinematics; stars : neutron; X-rays : stars ID X-RAY-EMISSION; RX J185635-3754; PROPER MOTIONS; STARS; VLBA; ASTROMETRY; EVOLUTION; ORIGIN AB We present the first pulsar parallaxes measured with phase-referenced pulsar VLBI observations at 5 GHz. Because of the steep spectra of pulsars, previous astrometric measurements have been at lower frequencies. However, the strongest pulsars can be observed at 5 GHz, offering the benefit of lower combined ionospheric and tropospheric phase errors, which usually limit VLBI astrometric accuracy. The pulsars B0329+54, B0355+54, and B1929+10 were observed for seven epochs spread evenly over 2 years. For B0329+54, large systematic errors led to only an upper limit on the parallax (pi< 1.5 mas). A new proper motion and parallax were measured for B0355+54 (π = 0.91 +/- 0.16 mas), implying a distance of 1.04(-0.16)(+0.21) kpc and a transverse velocity of 61(-9)(+12) km s(-1). The parallax and proper motion for B1929+ 10 were significantly improved (pi = 2.77 +/- 0.07 mas), yielding a distance of 361(-8)(+10) pc and a transverse velocity of 177(-5)(+4) km s(-1). We demonstrate that the astrometric errors are correlated with the angular separation between the phase-reference calibrator and the target source, with significantly lower errors at 5 GHz as compared to 1.6 GHz. Finally, based on our new distance determinations for B1929+ 10 and B0355+54, we derive or constrain the luminosities of each pulsar at high energies. We show that, for thermal emission models, the emitting area for X-rays from PSR B1929+ 10 is roughly consistent with the canonical size for a heated polar cap and that the conversion of spin-down power to gamma-ray luminosity in B0355+54 must be low. The new proper motion for B1929+ 10 also implies that its progenitor is unlikely to have been the binary companion of the runaway O star zeta Ophiuchi. C1 Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. NASA, Goddard Space Flight Ctr, USRA, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. USN, Res Lab, Washington, DC 20375 USA. RP Chatterjee, S (reprint author), Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. EM shami@astro.cornell.edu OI /0000-0002-2700-9916 NR 35 TC 62 Z9 63 U1 1 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2004 VL 604 IS 1 BP 339 EP 345 DI 10.1086/381748 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LU UT WOS:000220301000029 ER PT J AU Hoard, DW Linnell, AP Szkody, P Fried, RE Sion, EM Hubeny, I Wolfe, MA AF Hoard, DW Linnell, AP Szkody, P Fried, RE Sion, EM Hubeny, I Wolfe, MA TI The hot white dwarf in the cataclysmic variable MV Lyrae SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; novae, cataclysmic variables; stars : individual (MV Lyrae) ultraviolet : stars; white dwarfs ID ULTRAVIOLET-SPECTROSCOPIC-EXPLORER; HUBBLE-SPACE-TELESCOPE; ACCRETION DISKS; LOW STATES; VW HYDRI; STARS; MODEL; ATMOSPHERES; QUIESCENCE; SPECTRUM AB We have obtained the first far-ultraviolet spectrum of the nova-like cataclysmic variable MV Lyrae using the Far Ultraviolet Spectroscopic Explorer (FUSE). We also obtained contemporaneous optical light curves and spectra. All data are from a deep faint accretion state of MV Lyr. We constructed a model for the system using the BINSYN software package; results from this model include the following: (1) The white dwarf has T-eff = 47, 000 K, photospheric log g = 8.25, and metallicity of Z approximate to 0.3 Z(.). (2) The secondary star is cooler than 3500 K; it contributes nothing to the far-ultraviolet flux and a varying amount to the optical flux (from 10% at 5200 Angstrom to 60% at 7800 Angstrom). (3) The accretion disk, if present at all, contributes negligibly to the spectrum of MV Lyr. Irradiation considerations imply that the mass transfer rate is no more than 3 x 10(-13) M-. yr(-1). (4) Assuming no disk is present, the model optical light curve has an amplitude approximately 50% larger than that of the sinusoidal modulation (on the orbital period) in the observed optical light curve, suggesting that the secondary star might be shaded by a nascent disk and/or have starspots near the L1 point. (5) The scaling of the model spectrum to the observed data leads to a distance of d = 505 +/- 50 pc to MV Lyr. C1 CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Braeside Observ, Flagstaff, AZ 86002 USA. Villanova Univ, Dept Astron & Astrophys, Villanova, PA 19085 USA. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. RP Hoard, DW (reprint author), CALTECH, Spitzer Sci Ctr, Mail Code 220-6,1200 E Calif Blvd, Pasadena, CA 91125 USA. EM hoard@ipac.caltech.edu; linnell@astro.washington.edu; szkody@astro.washington.edu; captain@asu.edu; edward.sion@villanova.edu; hubeny@tlusty.gsfc.nasa.gov; maw2323@u.washington.edu OI Hoard, Donald W./0000-0002-6800-6519 NR 28 TC 34 Z9 34 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2004 VL 604 IS 1 BP 346 EP 356 DI 10.1086/381777 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LU UT WOS:000220301000030 ER PT J AU McIntosh, SW Poland, AI AF McIntosh, SW Poland, AI TI Detailed SUMER observations of coronal loop footpoint dynamics SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : atmospheric motions; Sun : magnetic fields; Sun : transition region; Sun : UV radiation ID SOLAR TRANSITION REGION; QUIET-SUN; SOHO; CHROMOSPHERE; TRACE; LINE AB For the most part, the characteristics of heating in the open corona and in closed coronal loops are determined by observing the emitted plasma intensity as a function of position and comparing this with model calculations. There are also some efforts that include observed velocity and still others that use theoretical physical processes such as electrodynamic or turbulent heating, for example. With a view toward future modeling endeavors, we investigate the temporal behavior of the intensity and velocity of a magnetic loop footpoint as observed by SUMER on the Solar and Heliospheric Observatory (SOHO) spacecraft as part of SOHO/TRACE Joint Observing Program 72. We study these quantities in emission lines that were specifically chosen to span the temperature domain of the upper chromospheric and transition region plasmas (10(5) - 10(6) K). We discuss the implications of these observations, suggest improvements, and present some new avenues of exploration. The most significant result is the demonstration of the importance of including the measurement of velocity as a function of time in the loop footpoint region. C1 Univ Space Res Assoc, Cooperat Program Space Sci, Seabrook, MD 20706 USA. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. George Mason Univ, Sch Computat Sci, Fairfax, VA 22030 USA. RP McIntosh, SW (reprint author), Univ Space Res Assoc, Cooperat Program Space Sci, Seabrook, MD 20706 USA. EM scott@grace.nascom.nasa.gov; apoland@scs.gmu.edu NR 24 TC 2 Z9 2 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2004 VL 604 IS 1 BP 449 EP 454 DI 10.1086/381776 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LU UT WOS:000220301000040 ER PT J AU Ravindranath, S Ferguson, HC Conselice, C Giavalisco, M Dickinson, M Chatzichristou, E de Mello, D Fall, SM Gardner, JP Grogin, NA Hornschemeier, A Jogee, S Koekemoer, A Kretchmer, C Livio, M Mobasher, B Somerville, R AF Ravindranath, S Ferguson, HC Conselice, C Giavalisco, M Dickinson, M Chatzichristou, E de Mello, D Fall, SM Gardner, JP Grogin, NA Hornschemeier, A Jogee, S Koekemoer, A Kretchmer, C Livio, M Mobasher, B Somerville, R TI The evolution of disk galaxies in the GOODS-South field: Number densities and size distribution1 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : evolution; galaxies : formation; galaxies : fundamental parameters galaxies : structure ID HIGH-REDSHIFT; IMAGES; BULGES AB We examine the evolution of the sizes and number densities of disk galaxies using the high-resolution images obtained by the Great Observatories Origins Deep Survey ( GOODS) with the Advanced Camera for Surveys on the Hubble Space Telescope. The multiwavelength images are used to classify galaxies based on their rest-frame B-band morphologies out to redshift z similar to 1.25. In order to minimize the effect of selection biases, we confine our analysis to galaxies that occupy the region of the magnitude-size plane where the survey is similar to 90% complete at all redshifts. The observed size distribution is consistent with a lognormal distribution as seen for the disk galaxies in the local universe and does not show any significant evolution over the redshift range. We 0.25 less than or equal to z less than or equal to 1.25 find that the number densities of disk galaxies remains fairly constant over this redshift range, although a modest evolution by a factor of 4 may be possible within the 2 sigma uncertainties. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. CALTECH, Pasadena, CA 91125 USA. Yale Univ, Dept Astron, New Haven, CT 06520 USA. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. RP Ravindranath, S (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. RI Conselice, Christopher/B-4348-2013; OI Conselice, Christopher/0000-0003-1949-7638; Koekemoer, Anton/0000-0002-6610-2048 NR 21 TC 122 Z9 123 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2004 VL 604 IS 1 BP L9 EP L12 DI 10.1086/382952 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LW UT WOS:000220301200003 ER PT J AU Vidal-Madjar, A Desert, JM des Etangs, AL Hebrard, G Ballester, GE Ehrenreich, D Ferlet, R McConnell, JC Mayor, M Parkinson, CD AF Vidal-Madjar, A Desert, JM des Etangs, AL Hebrard, G Ballester, GE Ehrenreich, D Ferlet, R McConnell, JC Mayor, M Parkinson, CD TI Detection of oxygen and carbon in the hydrodynamically escaping atmosphere of the extrasolar planet HD 209458b SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems; stars : individual (HD 209458) ID EVOLUTION AB Four transits of the planet orbiting the star HD 209458 were observed with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. The wavelength domain (1180 - 1710 Angstrom) includes H I as well as C I, C II, C IV, N v, O I, S I, Si II, Si III, and Si IV lines. During the transits, absorptions are detected in H I, O I, and C II (5% +/- 2%, 13% +/- 4.5%, and 7.5% +/- 3.5%, respectively). No absorptions are detected for other lines. The 5% mean absorption over the whole H I Lyalpha line is consistent with the previous detection completed in 2003 at higher resolution (Vidal-Madjar et al.). The absorption depths in O I and C II show that oxygen and carbon are present in the extended upper atmosphere of HD 209458b ( nicknamed "Osiris"). These species must be carried out up to the Roche lobe and beyond, most likely in a state of hydrodynamic escape. C1 CNRS, Inst Astrophys Paris, F-75014 Paris, France. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. York Univ, Dept Earth & Atmospher Sci, N York, ON M3J 1P3, Canada. Observ Geneva, CH-1290 Sauverny, Switzerland. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. NASA, Astrobiol Inst, Pasadena, CA 91125 USA. RP Vidal-Madjar, A (reprint author), CNRS, Inst Astrophys Paris, 98Bis,Blvd Arago, F-75014 Paris, France. EM alfred@iap.fr; desert@iap.fr; lecaveli@iap.fr; hebrard@iap.fr; gilda@vega.lpl.arizona.edu; ehrenrei@iap.fr; ferlet@iap.fr; jack@nimbus.yorku.ca; michel.mayor@obs.unige.ch; cdp@gps.caltech.edu OI Ehrenreich, David/0000-0001-9704-5405 NR 18 TC 276 Z9 279 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2004 VL 604 IS 1 BP L69 EP L72 DI 10.1086/383347 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LW UT WOS:000220301200018 ER PT J AU Sovinec, CR Glasser, AH Gianakon, TA Barnes, DC Nebel, RA Kruger, SE Schnack, DD Plimpton, SJ Tarditi, A Chu, MS AF Sovinec, CR Glasser, AH Gianakon, TA Barnes, DC Nebel, RA Kruger, SE Schnack, DD Plimpton, SJ Tarditi, A Chu, MS CA NIMROD Team TI Nonlinear magnetohydrodynamics simulation using high-order finite elements SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE magnetohydrodynamic simulation; finite element; semi-implicit; anisotropic diffusion ID DIFFUSE LINEAR PINCH; TEARING MODES; RESISTIVE INSTABILITIES; SEMIIMPLICIT METHOD; MAGNETIC-FIELD; STABILITY; COMPUTATIONS; TOKAMAKS; SUSTAINMENT; SPHEROMAK AB A conforming representation composed of 2D finite elements and finite Fourier series is applied to 3D nonlinear non-ideal magnetohydrodynamics using a semi-implicit time-advance. The self-adjoint semi-implicit operator and variational approach to spatial discretization are synergistic and enable simulation in the extremely stiff conditions found in high temperature plasmas without sacrificing the geometric flexibility needed for modeling laboratory experiments. Growth rates for resistive tearing modes with experimentally relevant Lundquist number are computed accurately with time-steps that are large with respect to the global Alfven time and moderate spatial resolution when the finite elements have basis functions of polynomial degree (p) two or larger. An error diffusion method controls the generation of magnetic divergence error. Convergence studies show that this approach is effective for continuous basis functions with p greater than or equal to 2, where the number of test functions for the divergence control terms is less than the number of degrees of freedom in the expansion for vector fields. Anisotropic thermal conduction at realistic ratios of parallel to perpindicular conductivity (chi(\\)/chi(perpendicular to)) is computed accurately with p greater than or equal to 3 without mesh alignment. A simulation of tearing -mode evolution for a shaped toroidal tokamak equilibrium demonstrates the effectiveness of the algorithm in nonlinear conditions, and its results are used to verify the accuracy of the numerical anisotropic thermal conduction in 3D magnetic topologies. (C) 2003 Elsevier Inc. All rights reserved. C1 Univ Wisconsin, Dept Engn Phys, Madison, WI 53706 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Sci Applicat Int Corp, San Diego, CA 92121 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. NASA, Lyndon B Johnson Space Ctr, Adv Space Prop Lab, Houston, TX 77050 USA. Gen Atom Co, San Diego, CA 92138 USA. RP Sovinec, CR (reprint author), Univ Wisconsin, Dept Engn Phys, 1500 Engn Dr, Madison, WI 53706 USA. EM sovinec@engr.wisc.edu NR 53 TC 234 Z9 235 U1 2 U2 33 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAR 20 PY 2004 VL 195 IS 1 BP 355 EP 386 DI 10.1016/j.jcp.2003.10.004 PG 32 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 804OX UT WOS:000220309100015 ER PT J AU Inamdar, AK Ramanathan, V Loeb, NG AF Inamdar, AK Ramanathan, V Loeb, NG TI Satellite observations of the water vapor greenhouse effect and column longwave cooling rates: Relative roles of the continuum and vibration-rotation to pure rotation bands SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE remote sensing; instruments and techniques; radiative processes ID EARTHS RADIATION BUDGET; ATMOSPHERIC HYDROLOGY; SURFACE-TEMPERATURE; CLIMATE; HUMIDITY; SENSITIVITY; OCEANS; ABSORPTION; DATASET; SYSTEM AB [1] The Clouds and the Earth's Radiant Energy System (CERES) instrument on board the Tropical Rainfall Measuring Mission (TRMM) satellite provides, for the first time, a large-scale (40 S to 40 N) data set for the atmospheric greenhouse effect and the column-averaged longwave (LW) radiative cooling rates in the broadband (5-100 microns) and the window (8-12 microns) regions. We demonstrate here that the separation into the window and the nonwindow (5-8 microns and 12-100 microns) fluxes provides the first global-scale data set to exhibit the sensitivity of the atmospheric greenhouse effect to vertical water vapor distribution. The nonwindow greenhouse effect varies linearly with the logarithm of column water vapor amount weighted with the atmospheric pressure, while the window component varies quadratically with the water vapor partial pressure. The column cooling rates range from about -170 to -210 W m(-2) for the nonwindow region. The window cooling rates are only about 10% to 20% of the above range and approach rapidly to near-zero values for surface temperatures less than 288 K. The nonwindow component of the greenhouse effect and cooling rates are shown to be more sensitive to upper troposphere water vapor, while the window greenhouse effect and cooling rates are shown to be more sensitive to the lower troposphere water vapor amount. In addition, the data reveal that in tropical regions, with warm sea surface temperatures (greater than 297 K) and elevated upper tropospheric water vapor amounts, the continuum emission in the window region leads to enhanced cooling of the column, while the rotational bands in the nonwindow region lead to a net decrease in the longwave cooling of the atmospheric column. C1 Univ Calif San Diego, Scripps Inst Oceanog, Ctr Clouds Chem & Climate, La Jolla, CA 92093 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Inamdar, AK (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Ctr Clouds Chem & Climate, Mail Code 0221, La Jolla, CA 92093 USA. EM ainamdar@ucsd.edu; ram@fiji.ucsd.edu; n.g.loeb@larc.nassa.gov NR 35 TC 9 Z9 9 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 20 PY 2004 VL 109 IS D6 AR D06104 DI 10.1029/2003JD003980 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806MN UT WOS:000220438100002 ER PT J AU Chen, SH Moore, TE AF Chen, SH Moore, TE TI Dayside flow bursts in the Earth's outer magnetosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE reconnection; magnetopause; solar wind-magnetosphere interaction; magnetosphere-ionosphere coupling; magnetic field line merging; plasma instabilities ID LATITUDE BOUNDARY-LAYER; PLASMASPHERIC MATERIAL; MAGNETIC RECONNECTION; SUBSOLAR MAGNETOPAUSE; GEOMAGNETIC-ACTIVITY; PLASMA REGIONS; FIELD; EVENTS; MODEL; LINE AB Observations from the Polar/Thermal Ion Dynamics Experiment indicate the presence of cold magnetospheric/ ionospheric H+, He+, and a trace of O+ in the vicinity of the subsolar magnetopause during intervals of moderate geomagnetic activity (Kp similar to 4). These cold ions were accelerated to a perpendicular speed (DeltaV(perpendicular toB)) of the order of 100 km s(-1) or 0.3 M-A outward, relative to the magnetopause boundary oscillations. The accelerated flows produced similar to4 mV m(-1) in convection electric field and carried similar to1-100 ions cm(-3) in number density or similar to0.1-5 x 10(8) ions cm(-2) s(-1) in particle flux or 4 x 10(25)- 2 x 10(27) ions s(-1) in transfer rate (assuming sunward convecting flux tube with latitudinal cross-section of 1 R-E in width and 10 R-E in length along magnetopause). This rate of plasma transfer from inside the magnetopause is comparable with that entering the LLBL with the same incident cross section on the magnetopause from the solar wind influx. The occurrence of these flow burst events is accompanied by changes in the local magnetic field orientation, departing from nominal magnetospheric magnetic field, and is sensitive to the variation in the IMF clock angle. We suggest that the magnetospheric/ ionospheric ions contribute plasma of dynamical significance to physical processes such as magnetic reconnection, for the cases presented in this study at the subsolar magnetopause. C1 NASA, Goddard Space Flight Ctr, Interplanetary Phys Branch, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Seabrook, MD USA. RP NASA, Goddard Space Flight Ctr, Interplanetary Phys Branch, Code 692, Greenbelt, MD 20771 USA. EM sheng-hsien.chen@gsfc.nasa.gov; thomas.e.moore@gsfc.nasa.gov RI Moore, Thomas/D-4675-2012 OI Moore, Thomas/0000-0002-3150-1137 NR 52 TC 16 Z9 16 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 20 PY 2004 VL 109 IS A3 AR A03215 DI 10.1029/2003JA010007 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 806NG UT WOS:000220440000001 ER PT J AU Colarco, PR Schoeberl, MR Doddridge, BG Marufu, LT Torres, O Welton, EJ AF Colarco, PR Schoeberl, MR Doddridge, BG Marufu, LT Torres, O Welton, EJ TI Transport of smoke from Canadian forest fires to the surface near Washington, D. C.: Injection height, entrainment, and optical properties SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE smoke aerosols; optical properties; entrainment ID 3-DIMENSIONAL MODEL; SATELLITE DETECTION; AEROSOL; BOREAL; PARTICLES; LIDAR; STRATOSPHERE; CONVECTION; RADIATION; NETWORK AB [1] Smoke and pollutants from Canadian forest fires are sometimes transported over the United States at low altitudes behind advancing cold fronts. An unusual event occurred in July 2002 in which smoke from fires in Quebec was observed by satellite, lidar, and aircraft to arrive over the Washington, D. C., area at high altitudes. This elevated smoke plume subsequently mixed to the surface as it was entrained into the turbulent planetary boundary layer and had adverse effects on the surface air quality over the region. Trajectory and three-dimensional model calculations confirmed the origin of the smoke, its transport at high altitudes, and the mechanism for bringing the pollutants to the surface. Additionally, the modeled smoke optical properties agreed well with aircraft and remote sensing observations provided the smoke particles were allowed to age by coagulation in the model. These results have important implications for the long-range transport of pollutants and their subsequent entrainment to the surface, as well as the evolving optical properties of smoke from boreal forest fires. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. Univ Maryland, Earth Syst Interdisciplinary Ctr, College Pk, MD USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. RP NASA, Goddard Space Flight Ctr, Code 916, Greenbelt, MD 20771 USA. EM colarco@essic.umd.edu RI Welton, Ellsworth/A-8362-2012; Torres, Omar/G-4929-2013; Colarco, Peter/D-8637-2012 OI Colarco, Peter/0000-0003-3525-1662 NR 41 TC 135 Z9 135 U1 1 U2 25 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 19 PY 2004 VL 109 IS D6 AR D06203 DI 10.1029/2003JD004248 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806MM UT WOS:000220438000006 ER PT J AU Zheng, QN Clemente-Colon, P Yan, XH Liu, WT Huang, NE AF Zheng, QN Clemente-Colon, P Yan, XH Liu, WT Huang, NE TI Satellite synthetic aperture radar detection of Delaware Bay plumes: Jet-like feature analysis SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article DE Delaware Bay; estuarine plume; radar image ID COASTAL CURRENT; BUOYANCY; ESTUARY; SHELF; MODEL AB From the physics of radar imaging of ocean surface processes a theoretical model for the radar imaging of an ocean jet was derived. The theoretical model predicts that the jet current structure, sech(2)eta, constitutes a determining factor for the radar image. The modeled image intensity depends on the axial velocity, decreasing as x(-1) along the jet axis, and is sensitive to the wind direction with respect to the jet axis. The model was used to interpret synthetic aperture radar (SAR) images of Delaware Bay plumes taken by the RADARSAT-1 (Canadian Radar Satellite) and ERS-2 (European Remote Sensing satellite) satellites during a period from summer 1996 to spring 1997. In all seasons the low-salinity plumes appear as relatively bright, jet-like patterns on SAR images. From a morphological interpretation of the image features, both summer and winter plumes can be divided into three sections along the axis: source, jet, and dispersion region. Along the transverse direction, SAR image interpretations indicate that the plumes have a twin jet structure, which conforms to decomposition of field measurements. In summer the typical axial velocity is estimated at 6 x 10(-1) m s(-1) with a Reynolds number of 18. At about 5 km downstream from the source the plume behaves like a turbulent jet, and beyond that range down to about 10 km downstream, it behaves like a laminar jet. In winter the plumes become weaker than in summer. The typical axial velocity is estimated at 4 x 10(-1) m s(-1) with a Reynolds number of 3. The jet behaves like the laminar jet off the source down to about 4 km downstream. In both summer and winter cases the SAR images were taken at maximum flood tide, and the plumes appeared as jets. In the spring case the SAR image was taken at early flood tide; the plume appeared as an integrated body with relatively uniform bright tunes. In all cases the plume disperses within about 25 km downstream. C1 Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. NOAA, NESDIS, Camp Springs, MD USA. Univ Delaware, Coll Marine Studies, Newark, DE USA. CALTECH, Jet Prop Lab 300 323, Pasadena, CA 91125 USA. NASA, Ocean & Ice Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Zheng, QN (reprint author), Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. EM quanan@atmos.umd.edu RI Zheng, Quanan/F-9025-2010; Clemente-Colon, Pablo/F-5581-2010 NR 17 TC 10 Z9 11 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 EI 2169-9291 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAR 19 PY 2004 VL 109 IS C3 AR C03031 DI 10.1029/2003JC002100 PG 11 WC Oceanography SC Oceanography GA 806MR UT WOS:000220438500003 ER PT J AU Schubert, SD Suarez, MJ Pegion, PJ Koster, RD Bacmeister, JT AF Schubert, SD Suarez, MJ Pegion, PJ Koster, RD Bacmeister, JT TI On the cause of the 1930s Dust Bowl SO SCIENCE LA English DT Article ID SEA-SURFACE TEMPERATURE; CENTRAL UNITED-STATES; DROUGHT; VARIABILITY; PRECIPITATION; ENSO AB During the 1930s, the United States experienced one of the most devastating droughts of the past century. The drought affected almost two-thirds of the country and parts of Mexico and Canada and was infamous for the numerous dust storms that occurred in the southern Great Plains. In this study, we present model results that indicate that the drought was caused by anomalous tropical sea surface temperatures during that decade and that interactions between the atmosphere and the land surface increased its severity. We also contrast the 1930s drought with other North American droughts of the 20th century. C1 NASA, Goddard Space Flight Ctr, Earth Sci Directorate, Greenbelt, MD 20771 USA. Sci Applicat Int Corp, Beltsville, MD 20705 USA. Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA. RP NASA, Goddard Space Flight Ctr, Earth Sci Directorate, Greenbelt, MD 20771 USA. EM schubert@gmao.gsfc.nasa.gov RI Pegion, Philip/E-5247-2012; Koster, Randal/F-5881-2012 OI Koster, Randal/0000-0001-6418-6383 NR 20 TC 280 Z9 288 U1 11 U2 80 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 EI 1095-9203 J9 SCIENCE JI Science PD MAR 19 PY 2004 VL 303 IS 5665 BP 1855 EP 1859 DI 10.1126/science.1095048 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 804EI UT WOS:000220281600052 PM 15031502 ER PT J AU Matsui, T Masunaga, H Pielke, RA Tao, WK AF Matsui, T Masunaga, H Pielke, RA Tao, WK TI Impact of aerosols and atmospheric thermodynamics on cloud properties within the climate system SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MARITIME LOW CLOUDS; VISIBLE/INFRARED SCANNER; PHYSICAL-PROPERTIES; MICROWAVE IMAGER; SATELLITE; RAIN AB [1] A combination of cloud-top and columnar droplet sizes derived from the multi Tropical Rainfall Measurement Mission (TRMM) sensors reveals the sensitivity of the aerosols effect on cloud-precipitation processes due to environmental vertical thermodynamic structure. First, the magnitude of aerosol indirect effect could be larger with the analysis of columnar droplet sizes than that derived from the cloud-top droplet sizes since column-droplet size can account for the broader droplet spectra in the cloud layers. Second, a combination of cloud-top and columnar droplet sizes reveals that the warm rain process is prevented regardless of the aerosols concentration under high static stability such as when a strong temperature inversion exists, while a high aerosol concentration suppresses the warm rain formulation under low static stability. C1 Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. NASA, Atmospheres Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Matsui, T (reprint author), Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. EM matsuit@atmos.colostate.edu RI Masunaga, Hirohiko/C-2488-2008; Pielke, Roger/A-5015-2009; PMM, JAXA/K-8537-2016 OI Masunaga, Hirohiko/0000-0002-6336-5002; NR 15 TC 20 Z9 21 U1 0 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 18 PY 2004 VL 31 IS 6 AR L06109 DI 10.1029/2003GL019287 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 806LY UT WOS:000220436600008 ER PT J AU Reid, JS Prins, EM Westphal, DL Schmidt, CC Richardson, KA Christopher, SA Eck, TF Reid, EA Curtis, CA Hoffman, JP AF Reid, JS Prins, EM Westphal, DL Schmidt, CC Richardson, KA Christopher, SA Eck, TF Reid, EA Curtis, CA Hoffman, JP TI Real-time monitoring of South American smoke particle emissions and transport using a coupled remote sensing/box-model approach SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SCAR-B; BRAZIL; BIOMASS; SENSITIVITY; FIRE AB [1] Since August 2000, the Wild fire Automated Biomass Burning Algorithm (WF_ABBA) has been generating half-hourly fire hot spot analyses for the Western Hemisphere using GOES satellites to provide the Naval Research Laboratory (NRL) Aerosol Analysis and Prediction System (NAAPS) with near-real-time fire products. These are used to generate smoke particle fluxes for aerosol transport forecasting to benefit the scientific, weather, and regulatory communities. In South America, fire hot-spot analysis is shown to be adequate for generating real-time smoke source functions for aerosol forecast models. We present smoke coverage and flux estimates based on the WF_ABBA and NAAPS products. Modeled fluxes of emissions for 2001-2002 are similar to25 + 10 Tg yr(-1), similar to previous estimates. Correlations of optical depth with MODIS and AERONET show good agreement with observations. Comparisons of NAAPS aerosol fields with MODIS also show potential clear sky and other biases as smoke is transported into the Atlantic Ocean and the ITCZ. C1 USN, Res Lab, Monterey, CA 93943 USA. NOAA, NESDIS, Off Res & Applicat, Madison, WI USA. Univ Wisconsin, CIMSS, Dept Meteorol, Madison, WI 53706 USA. Univ Alabama, Dept Atmospher Sci, Huntsville, AL 35805 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Sci Applicat Int Corp, Monterey, CA 93943 USA. Univ Oklahoma, Dept Meteorol, Norman, OK 73019 USA. RP Reid, JS (reprint author), USN, Res Lab, 7 Grace Hopper St,Stop 2, Monterey, CA 93943 USA. EM reidj@nrlmry.navy.mil RI Christopher, Sundar/E-6781-2011; ECK, THOMAS/D-7407-2012; Reid, Jeffrey/B-7633-2014; OI Reid, Jeffrey/0000-0002-5147-7955; HOFFMAN, JAY/0000-0002-1127-6294 NR 18 TC 58 Z9 59 U1 0 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 18 PY 2004 VL 31 IS 6 AR L06107 DI 10.1029/2003GL018845 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 806LY UT WOS:000220436600003 ER PT J AU Parker, JK Payne, WA Cody, RJ Stief, LJ AF Parker, JK Payne, WA Cody, RJ Stief, LJ TI Kinetics of the reaction of atomic hydrogen with cyanoacetylene from T=200 to 298 K SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID QUADRATIC CONFIGURATION-INTERACTION; THERMAL UNIMOLECULAR REACTIONS; MOLECULAR-ORBITAL METHODS; COLLISION RATE CONSTANTS; COUPLED-CLUSTER SINGLES; GAUSSIAN-BASIS SETS; FALL-OFF RANGE; TITANS ATMOSPHERE; TEMPERATURE-RANGE; PHOTOCHEMISTRY AB Rate coefficients have been measured for the H + HC3N (cyanoacetylene) reaction at T = 200, 250, and 298 K and at P = 0.5, 1.0, and 2.0 Torr He using a discharge-flow mass spectrometry apparatus. The reaction was monitored under pseudo-first-order conditions with the H atom concentration in large excess over the HC3N concentration ([H]/[HC3N] = 100-665). H atoms were generated by the fast reaction F + H-2 --> H + HF or by microwave discharge in H2. Fluorine atoms were produced by microwave discharge in an approximately 5% mixture of F-2 in He. Low-energy (24 eV) electron-impact mass spectrometry was used to monitor the HC3N decay kinetics to obtain the bimolecular rate coefficients. At T = 298 K the rate coefficients were found to be pressure independent over the range of pressures studied with an average value k = (2.1 +/- 0.3) x 10(-13) cm(3) molecule(-1) s(-1). This implies that the high-pressure limit is reached in these experiments not only at T = 298 K but also at the two lower temperatures. The temperature dependence of the measured high-pressure limiting rate coefficients is given by the following Arrhenius expression: k = (1.1 +/- 0.1) x 10(-12) exp[-(500 +/- 14)K/T] cm(3) molecule(-1) s(-1). A transition state theory model using G2M or CCSD(T) energies and Eckart tunneling corrections has been employed to calculate high-pressure limiting rate coefficients for this reaction. The reaction's mechanism and implications to the atmospheric chemistry of Titan are discussed. C1 NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RP Cody, RJ (reprint author), NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. EM Regina.J.Cody@nasa.gov RI Cody, Regina/D-5996-2013 NR 46 TC 5 Z9 5 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD MAR 18 PY 2004 VL 108 IS 11 BP 1938 EP 1945 DI 10.1021/jp037142a PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 803ZC UT WOS:000220268000009 ER PT J AU White, N AF White, N TI Astronomy - We can see clearly now ... SO NATURE LA English DT Editorial Material C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP White, N (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. EM nicholas.e.white@nasa.gov RI White, Nicholas/B-6428-2012 OI White, Nicholas/0000-0003-3853-3462 NR 0 TC 2 Z9 2 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAR 18 PY 2004 VL 428 IS 6980 BP 264 EP 265 DI 10.1038/428264a PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 803SG UT WOS:000220250200023 PM 15029176 ER PT J AU DeLand, MT Cebula, RP Hilsenrath, E AF DeLand, MT Cebula, RP Hilsenrath, E TI Observations of solar spectral irradiance change during cycle 22 from NOAA-9 Solar Backscattered Ultraviolet Model 2 (SBUV/2) SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE solar ultraviolet irradiance; solar variability; solar cycle ID MIDDLE ATMOSPHERE; OZONE RESPONSE; VARIABILITY; INSTRUMENT; SSBUV; FLUX; CALIBRATION; VALIDATION; SOLAR-CYCLE-21; SENSITIVITY AB [1] The NOAA-9 Solar Backscatter Ultraviolet Model 2 (SBUV/2) instrument is one of a series of instruments providing daily solar spectral irradiance measurements in the middle and near ultraviolet since 1978. The SBUV/2 instruments are primarily designed to measure the stratospheric profile and total column amount of ozone, using the directional albedo as the input to the ozone retrieval algorithm. Almost all optical components are common to both radiance and irradiance measurements, whose ratio forms the directional albedo, so that most response changes cancel out. As a result, the SBUV/2 instrument does not require onboard monitoring of time-dependent sensitivity changes for production of ozone data. We use vicarious comparisons with coincident Shuttle SBUV (SSBUV) solar irradiance measurements during 1989-1996, combined with observed calibration drift during the solar activity minimum in 1985-1986, to determine the long-term instrument characterization for NOAA-9 SBUV/2. This approach allows us to derive more accurate solar spectral irradiances for the period from March 1985 to May 1997, spanning two solar cycle minima with a single instrument. The NOAA-9 irradiance data show an amplitude of approximately 9.3% at 200-205 nm for solar cycle 22. This is consistent with the result of DeltaF(200)-(205) = 8.3% for cycle 21 from Nimbus-7 SBUV and DeltaF(200-205) = 10% for cycle 23 from UARS SUSIM. NOAA-9 data at 245-250 nm show a solar cycle amplitude of similar to5.7%. The observed irradiance change at 200-205 nm between the minima of solar cycles 21 and 22 is not consistent with the UV irradiance change expected from the total solar irradiance trend suggested by Willson and Mordvinov [2003]. NOAA-9 SBUV/2 data can be combined with data from other instruments to create a 25-year record of solar UV irradiance. C1 Sci Syst & Applicat Inc, Lanham, MD 20706 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP DeLand, MT (reprint author), Sci Syst & Applicat Inc, 10210 Greenbelt Rd,Suite 400, Lanham, MD 20706 USA. EM matthew_deland@ssaihq.com NR 48 TC 12 Z9 13 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 17 PY 2004 VL 109 IS D6 AR D06304 DI 10.1029/2003JD004074 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806ML UT WOS:000220437900003 ER PT J AU Loughman, RP Griffioen, E Oikarinen, L Postylyakov, OV Rozanov, A Flittner, DE Rault, DF AF Loughman, RP Griffioen, E Oikarinen, L Postylyakov, OV Rozanov, A Flittner, DE Rault, DF TI Comparison of radiative transfer models for limb-viewing scattered sunlight measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE radiative transfer; limb scattering; model comparison ID SOLAR MESOSPHERE EXPLORER; PICARD ITERATIVE APPROXIMATION; DIFFERENTIAL-INTEGRAL APPROACH; SPHERICAL-SHELL ATMOSPHERE; MINOR SPECIES DENSITIES; RAYLEIGH-SCATTERING; ODIN SATELLITE; OZONE PROFILES; O-3 PROFILES; RADIANCE AB [1] This study compares the limb scattered radiances calculated by six radiative transfer models for a variety of viewing conditions. Atmospheres that include molecular scattering, aerosol scattering, and ozone absorption are considered. All models treat single scattering accurately in full spherical geometry. Two "approximate spherical'' models (CDI and LIMBTRAN) rely on the plane-parallel atmosphere approximation to calculate the diffuse radiance field; the remaining four "spherical'' models (Siro, MCC++, GSLS, and CDIPI) treat multiple scattering in a spherical atmosphere. Only three of the models (Siro, MCC++, and GSLS) have vector treatment with polarization. A brief comparison of vector radiances with the limb scattered radiances measured by the SOLSE and LORE instruments demonstrates agreement usually within 15% and always within 30%. The inclusion of polarization appears to have little effect on the level of agreement among the models (which agree to within 2% for this sample case). A more general comparison among calculated scalar radiances follows, including four solar zenith angles (20degrees, 60degrees, 80degrees, and 90degrees), three relative azimuth angles (20degrees, 90degrees, and 160degrees), and two surface albedos (0 and 0.95). The single scattered radiances agree to within 1% for almost every case. Comparisons of the total radiance show larger differences, with 2-4% spread among the results of the spherical models. The approximate spherical models show a positive radiance difference relative to the other models that increases with tangent height, reaching as much as 8% at 60 km. The rule used to divide the model atmosphere into discrete layers is shown to affect the calculated radiance, causing a height-dependent difference of up to 1% for 1 km layer thickness. C1 NASA, Langley Res Ctr, Radiat & Aerosaol Branch, Hampton, VA 23681 USA. Finnish Meteorol Inst, Geophys Res Div, FIN-00101 Helsinki, Finland. Univ Bremen, Inst Environm Phys, D-28359 Bremen, Germany. Univ Bremen, Inst Remote Sensing, D-28359 Bremen, Germany. Univ Arizona, Inst Atmospher Phys, Tucson, AZ 85721 USA. York Univ, N York, ON M3J 1P3, Canada. Russian Acad Sci, AM Obuhov Inst Atmospher Phys, Moscow, Russia. RP Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. EM robert.loughman@hamptonu.edu RI Postylyakov, Oleg/E-6310-2014 OI Postylyakov, Oleg/0000-0003-4202-1945 NR 69 TC 35 Z9 37 U1 2 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 17 PY 2004 VL 109 IS D6 AR D06303 DI 10.1029/2003JD003854 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806ML UT WOS:000220437900001 ER PT J AU Popp, PJ Gao, RS Marcy, TP Fahey, DW Hudson, PK Thompson, TL Karcher, B Ridley, BA Weinheimer, AJ Knapp, DJ Montzka, DD Baumgardner, D Garrett, TJ Weinstock, EM Smith, JB Sayres, DS Pittman, JV Dhaniyala, S Bui, TP Mahoney, MJ AF Popp, PJ Gao, RS Marcy, TP Fahey, DW Hudson, PK Thompson, TL Karcher, B Ridley, BA Weinheimer, AJ Knapp, DJ Montzka, DD Baumgardner, D Garrett, TJ Weinstock, EM Smith, JB Sayres, DS Pittman, JV Dhaniyala, S Bui, TP Mahoney, MJ TI Nitric acid uptake on subtropical cirrus cloud particles SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE cirrus clouds; nitric acid; uptake; ice particles ID IN-SITU MEASUREMENTS; HIGH-LEVEL CLOUDS; UPPER TROPOSPHERE; ICE PARTICLES; LOWER STRATOSPHERE; NASA ER-2; WATER-ICE; HNO3; AEROSOL; MODEL AB [1] The redistribution of HNO3 via uptake and sedimentation by cirrus cloud particles is considered an important term in the upper tropospheric budget of reactive nitrogen. Numerous cirrus cloud encounters by the NASA WB-57F high-altitude research aircraft during the Cirrus Regional Study of Tropical Anvils and Cirrus Layers-Florida Area Cirrus Experiment (CRYSTAL-FACE) were accompanied by the observation of condensed-phase HNO3 with the NOAA chemical ionization mass spectrometer. The instrument measures HNO3 with two independent channels of detection connected to separate forward and downward facing inlets that allow a determination of the amount of HNO3 condensed on ice particles. Subtropical cirrus clouds, as indicated by the presence of ice particles, were observed coincident with condensed-phase HNO3 at temperatures of 197-224 K and pressures of 122-224 hPa. Maximum levels of condensed-phase HNO3 approached the gas-phase equivalent of 0.8 ppbv. Ice particle surface coverages as high as 1.4 x 10(14) molecules cm(-2) were observed. A dissociative Langmuir adsorption model, when using an empirically derived HNO3 adsorption enthalpy of -11.0 kcal mol(-1), effectively describes the observed molecular coverages to within a factor of 5. The percentage of total HNO3 in the condensed phase ranged from near zero to 100% in the observed cirrus clouds. With volume-weighted mean particle diameters up to 700 mm and particle fall velocities up to 10 m s(-1), some observed clouds have significant potential to redistribute HNO3 in the upper troposphere. C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. Univ Nacl Autonoma Mexico, Ctr Ciencias Atmosfera, Mexico City 04510, DF, Mexico. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Clarkson Univ, Dept Mech & Aeronaut Engn, Potsdam, NY 13699 USA. Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. Deutsch Zentrum Luft & Raumfahrt, Inst Phys Atmosphare, D-82234 Wessling, Germany. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. Harvard Univ, Atmospher Res Project, Cambridge, MA 02138 USA. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP NOAA, Aeron Lab, Boulder, CO 80305 USA. EM ppopp@al.noaa.gov RI Gao, Ru-Shan/H-7455-2013; Karcher, Bernd/D-5325-2014; Fahey, David/G-4499-2013 OI Karcher, Bernd/0000-0003-0278-4980; Fahey, David/0000-0003-1720-0634 NR 44 TC 52 Z9 53 U1 0 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 17 PY 2004 VL 109 IS D6 AR D06302 DI 10.1029/2003JD004255 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806ML UT WOS:000220437900006 ER PT J AU Liemohn, MW Ridley, AJ Gallagher, DL Ober, DM Kozyra, JU AF Liemohn, MW Ridley, AJ Gallagher, DL Ober, DM Kozyra, JU TI Dependence of plasmaspheric morphology on the electric field description during the recovery phase of the 17 April 2002 magnetic storm SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE plasmapause location; magnetosphere-ionosphere coupling; magnetic storms ID PARKER-SCKOPKE RELATION; ASYMMETRIC RING CURRENT; MAGNETOSPHERIC CONVECTION; GEOMAGNETIC STORMS; EQUATORIAL MAGNETOSPHERE; INNER MAGNETOSPHERE; ALIGNED CURRENTS; IMAGE MISSION; CORE PLASMA; LARGE-SCALE AB A comparison of how well three different electric field models can predict the storm time plasmapause shape is conducted. The magnetic storm of 17 April 2002 is selected for this event, and plasmapause locations are extracted from images from the EUV instrument on the Imager for Magnetopause-to-Aurora Geomagnetic Effects (IMAGE) satellite throughout the main phase and recovery phase of the event. The three electric field descriptions are as follows: the modified McIlwain E5D analytical formula, the Weimer statistical compilation from low-Earth orbit satellite data, and a self-consistent Poisson equation solution for the subauroral potential pattern. It is found that all of the models have certain strengths and weaknesses in predicting the plasmapause location during this storm. The modified McIlwain model did well on the nightside but not on the dayside because the electric fields near noon are too small (analogous to too large of a conductance in the subauroral dayside ionosphere). The Weimer model did well overall, but the resulting plasmapause is usually smaller than the observed one because the electric fields are a bit too strong in the inner magnetosphere (perhaps because of an ionosphere-magnetosphere mapping problem). The self-consistent model is also quite good in general, but the plasmapause in the postmidnight sector was always inward of the observed one. This is because of too low a conductance at the location of the field-aligned currents that close the partial ring current. It is concluded that the latter two models provide a sufficient description of the storm time development of the plasmaspheric morphology during this storm, with the self-consistent model being the best choice. Another conclusion is that plasmapause locations extracted from EUV images should be compared with peak density gradients from model results rather than with any one isocontour of the cold plasma density itself. C1 Univ Michigan, Dept Atmospher Ocean & Space Sci, Ctr Space Environm Modeling, Ann Arbor, MI 48109 USA. NASA, Natl Space Sci & Technol Ctr, Marshall Space Flight Ctr, Huntsville, AL 35899 USA. Mission Res Corp, Nashua, NH 03062 USA. RP Liemohn, MW (reprint author), Univ Michigan, Dept Atmospher Ocean & Space Sci, Ctr Space Environm Modeling, 2455 Hayward St, Ann Arbor, MI 48109 USA. EM liemohn@umich.edu; ridley@umich.edu; dennis.l.gallagher@nasa.gov; daniel.ober@mrcnh.com; jukozyra@umich.edu RI Liemohn, Michael/H-8703-2012; Ridley, Aaron/F-3943-2011 OI Liemohn, Michael/0000-0002-7039-2631; Ridley, Aaron/0000-0001-6933-8534 NR 71 TC 55 Z9 55 U1 2 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 16 PY 2004 VL 109 IS A3 AR A03209 DI 10.1029/2003JA010304 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 806NE UT WOS:000220439800001 ER PT J AU Li, C Fan, WD Lei, B Zhang, DH Han, S Tang, T Liu, XL Liu, ZQ Asano, S Meyyappan, M Han, J Zhou, CW AF Li, C Fan, WD Lei, B Zhang, DH Han, S Tang, T Liu, XL Liu, ZQ Asano, S Meyyappan, M Han, J Zhou, CW TI Multilevel memory based on molecular devices SO APPLIED PHYSICS LETTERS LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; CRYSTALLINE IN2O3 NANOWIRES AB Multilevel molecular memory devices were proposed and demonstrated for nonvolatile data storage up to three bits (eight levels) per cell, in contrast to the standard one-bit-per-cell (two levels) technology. In the demonstration, charges were precisely placed at up to eight discrete levels in redox active molecules self-assembled on single-crystal semiconducting nanowire field-effect transistors. Gate voltage pulses and current sensing were used for writing and reading operations, respectively. Charge storage stability was tested up to retention of 600 h, as compared to the longest retention of a few hours previously reported for one-bit-per-cell molecular memories. (C) 2004 American Institute of Physics. C1 Univ So Calif, Dept EE Electrophys, Los Angeles, CA 90089 USA. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Zhou, CW (reprint author), Univ So Calif, Dept EE Electrophys, Los Angeles, CA 90089 USA. EM chongwuz@usc.edu RI Tang, Tao/C-8123-2011; Zhou, Chongwu/F-7483-2010 NR 13 TC 93 Z9 96 U1 0 U2 19 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 15 PY 2004 VL 84 IS 11 BP 1949 EP 1951 DI 10.1063/1.1667615 PG 3 WC Physics, Applied SC Physics GA 802SG UT WOS:000220182600045 ER PT J AU Omoregie, EO Crumbliss, LL Bebout, BM Zehr, JP AF Omoregie, EO Crumbliss, LL Bebout, BM Zehr, JP TI Comparison of diazotroph community structure in Lyngbya sp and Microcoleus chthonoplastes dominated microbial mats from Guerrero Negro, Baja, Mexico SO FEMS MICROBIOLOGY ECOLOGY LA English DT Article DE nitrogenase; nifH; polymerase chain reaction; cyanobacterial mat; nitrogen fixation; Microcoleus; Lyngbya ID NITROGEN-FIXATION GENES; BAHAMIAN HYPERSALINE LAGOON; N-2 FIXATION; UNICELLULAR CYANOBACTERIA; BENTHIC CYANOBACTERIA; DINITROGEN FIXATION; MARINE ECOSYSTEMS; REDUCING BACTERIA; DIVERSITY; OXYGEN AB The nitrogenase activity and phylogenetic diversity of nitrogen fixing microorganisms in several different cyanobacterial mat types from Guerrero Negro, Baja California, Mexico were investigated by acetylene reduction assay, and by amplification and sequencing of the nitrogenase nifH gene. Acetylene reduction assays performed on a Lyngbya sp. and two Microcoleus chthonoplastes dominated microbial mats showed a typical diel pattern of nitrogenase activity in these mats. The highest rates of activity were found at night, with 40 and 37 mumol C2H4 m(-2) h(-1) measured in the Microcoleus mats, and 9 mumol C2H4 m(-2) h(-1) in the Lyngbya mat. Nitrogenase sequences were obtained that clustered with sequences from cyanobacteria, gamma-Proteobacteria, and cluster 3 of nifH. In addition, novel and divergent sequences were also recovered. The composition of nifH sequence types recovered differed between the Lyngbya and Microcoleus mats. Interestingly, nifH sequences belonging to filamentous cyanobacteria were absent in most mat samples even though both mats were dominated by filamentous cyanobacteria. nifH sequences clustering with those of unicellular cyanobacteria were found, some of which were virtually identical to the nifH sequence from Halothece sp. MP196P605, which had previously been isolated from the mat. In manipulation experiments, the Lyngbya and Microcoleus mats were allowed to re-colonize a cleared surface. In these developing mats, nifH sequences not previously observed in the mats were discovered. Our results showed that organisms capable of N-2 fixation were present in N-2 fixing mats, that the composition of the N-2 fixing communities differs between mats, and that filamentous cyanobacterial diazotrophs may not have a large role in the early stages of mat development. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved. C1 Univ Calif Santa Cruz, Dept Ocean Sci, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Inst Marine Sci, Santa Cruz, CA 95064 USA. NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. RP Zehr, JP (reprint author), Univ Calif Santa Cruz, Dept Ocean Sci, Earth & Marine Sci Bldg,1156 High St, Santa Cruz, CA 95064 USA. EM zehrj@ucsc.edu RI Zehr, Jonathan/B-3513-2014; OI Zehr, Jonathan/0000-0002-5691-5408; Omoregie, Enoma O./0000-0003-0667-8974 NR 58 TC 33 Z9 35 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-6496 J9 FEMS MICROBIOL ECOL JI FEMS Microbiol. Ecol. PD MAR 15 PY 2004 VL 47 IS 3 BP 305 EP 318 DI 10.1016/S0168-6496(03)00301-5 PG 14 WC Microbiology SC Microbiology GA 803XO UT WOS:000220264000005 PM 19712319 ER PT J AU Barlow, DA Baird, JK Su, CH AF Barlow, DA Baird, JK Su, CH TI Theory of the von Weimarn rules governing the average size of crystals precipitated from a supersaturated solution SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE nucleation; growth from solutions; von Weimarn rules ID NUCLEATION THEORY; BATCH CRYSTALLIZATION; KINETICS; GROWTH AB More than 75 years ago, von Weimarn summarized his observations of the dependence of the average crystal size on the initial relative concentration supersaturation prevailing in a solution from which crystals were growing. Since then, his empirically derived "rules" have become part of the lore of crystal growth. The first of these rules asserts that the average crystal size measured at the end of a crystallization increases as the initial value of the relative supersaturation decreases. The second rule states that for a given crystallization time, the average crystal size passes through a maximum as a function of the initial relative supersaturation. Using a theory of nucleation and growth due to Buyevich and Mansurov (J. Crystal Growth 104 (1990) 861), we calculate the average crystal size as a function of the initial relative supersaturation. We confirm the von Weimarn rules for the case where the nucleation rate is proportional to the third power or higher of the relative supersaturation. (C) 2004 Elsevier B.V. All rights reserved. C1 Univ Alabama, Mat Sci Program, Huntsville, AL 35899 USA. Univ Alabama, Dept Chem, Huntsville, AL 35899 USA. NASA, Marshall Space Flight Ctr, Sci Directorate, SD46, Huntsville, AL 35812 USA. RP Baird, JK (reprint author), Univ Alabama, Mat Sci Program, Mat Sci Bldg,John Wright Dr, Huntsville, AL 35899 USA. EM jkbaird@matsci.uah.edu NR 26 TC 30 Z9 31 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR 15 PY 2004 VL 264 IS 1-3 BP 417 EP 423 DI 10.1016/j.jcrysgro.2003.12.047 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 805CW UT WOS:000220345400065 ER PT J AU Singh, J Wolfe, DE Miller, RA Eldridge, JI Zhu, DM AF Singh, J Wolfe, DE Miller, RA Eldridge, JI Zhu, DM TI Tailored microstructure of zirconia and hafnia-based thermal barrier coatings with low thermal conductivity and high hemispherical reflectance by EB-PVD SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB Zirconia and hafnia based thermal barrier coating materials were produced by industrial prototype electron beam-physical vapor deposition (EB-PVD). Columnar microstructure of the thermal barrier coatings were modified with controlled microporosity and diffuse sub-interfaces resulting in lower thermal conductivity ( 20 - 30% depending up on microporosity volume fraction), higher thermal reflectance ( 15 - 20%) and more strain tolerance as compared with standard thermal barrier coatings (TBC). The novel processed coating systems were examined by various techniques including scanning electron microscopy (SEM), X-ray diffraction, thermal conductivity by laser technique, and hemispherical reflectance. (C) 2004 Kluwer Academic Publishers. C1 Penn State Univ, Appl Res Lab, University Pk, PA 16801 USA. NASA, GRC, Cleveland, OH 44135 USA. RP Singh, J (reprint author), Penn State Univ, Appl Res Lab, University Pk, PA 16801 USA. EM jxs46@psu.edu NR 6 TC 38 Z9 45 U1 3 U2 12 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAR 15 PY 2004 VL 39 IS 6 BP 1975 EP 1985 DI 10.1023/B:JMSC.0000017759.50800.d7 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 778KD UT WOS:000189240000007 ER PT J AU Matsko, AB Savchenkov, AA Ilchenko, VS Maleki, L AF Matsko, AB Savchenkov, AA Ilchenko, VS Maleki, L TI Optical gyroscope with whispering gallery mode optical cavities SO OPTICS COMMUNICATIONS LA English DT Article DE optical gyroscope; whispering gallery mode; slow light ID RING-RESONATOR; MICROSPHERE RESONATORS; HIGH-FINESSE; WAVE-GUIDES; MICROCAVITY AB We propose a miniature optical gyroscope based on a waveguide coupled sequence of whispering gallery mode microresonators. Sensitivity of this sensor is expected to be large due to large dispersion of the system. (C) 2004 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Matsko, AB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Andrey.Matsko@jpl.nasa.gov RI Matsko, Andrey/A-1272-2007 NR 22 TC 78 Z9 86 U1 3 U2 30 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD MAR 15 PY 2004 VL 233 IS 1-3 BP 107 EP 112 DI 10.1016/j.optcom.2004.01.035 PG 6 WC Optics SC Optics GA 800FQ UT WOS:000220014700014 ER PT J AU Maslov, AV Ning, CZ AF Maslov, AV Ning, CZ TI Far-field emission of a semiconductor nanowire laser SO OPTICS LETTERS LA English DT Article AB The polarization properties and angular distribution of intensity of the far fields from a nanowire laser are investigated. The far-field emission depends strongly on the mode type (HE11, TE01, TM01) and the radius of the nanowire. The emission is weakly directional, and a large part of it can be emitted in the backward direction. Our results can be applied for experimental determination of a lasing mode by its far fields as well as for optimization of laser emission. (C) 2004 Optical Society of America. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Maslov, AV (reprint author), NASA, Ames Res Ctr, Ctr Nanotechnol, MS 229-1, Moffett Field, CA 94035 USA. EM amaslov@nas.nasa.gov; cning@mail.arc.nasa.gov RI Maslov, Alexey/E-5158-2011; Ning, C. Z./D-4699-2009 OI Maslov, Alexey/0000-0002-7835-2474; Ning, C. Z./0000-0003-4583-8889 NR 5 TC 71 Z9 72 U1 1 U2 14 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAR 15 PY 2004 VL 29 IS 6 BP 572 EP 574 DI 10.1364/OL.29.000572 PG 3 WC Optics SC Optics GA 779TE UT WOS:000189316100014 PM 15035474 ER PT J AU Barkan, A Tittel, FK Mittleman, DM Dengler, R Siegel, PH Scalari, G Ajili, L Faist, J Beere, HE Linfield, EH Davies, AG Ritchie, DA AF Barkan, A Tittel, FK Mittleman, DM Dengler, R Siegel, PH Scalari, G Ajili, L Faist, J Beere, HE Linfield, EH Davies, AG Ritchie, DA TI Linewidth and tuning characteristics of terahertz quantum cascade lasers SO OPTICS LETTERS LA English DT Article ID DISTRIBUTED-FEEDBACK LASERS; MU-M; SPECTROSCOPY AB We have measured the spectral linewidths of three continuous-wave quantum cascade lasers operating at terahertz frequencies by heterodyning the free-running quantum cascade laser with two far-infrared gas lasers. Beat notes are detected with a GaAs diode mixer and a microwave spectrum analyzer, permitting very precise frequency measurements and giving instantaneous linewidths of less than similar to30 kHz. Characteristics are also reported for frequency tuning as the injection current is varied. (C) 2004 Optical Society of America. C1 Rice Univ, Dept Elect & Comp Engn, Houston, TX 77251 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Neuchatel, Inst Phys, CH-2000 Neuchatel, Switzerland. Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England. RP Barkan, A (reprint author), Rice Univ, Dept Elect & Comp Engn, MS-366, Houston, TX 77251 USA. EM daniel@rice.edu RI Faist, Jerome/A-7339-2013; OI Faist, Jerome/0000-0003-4429-7988; Linfield, Edmund/0000-0001-6912-0535 NR 21 TC 84 Z9 86 U1 2 U2 16 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAR 15 PY 2004 VL 29 IS 6 BP 575 EP 577 DI 10.1364/OL.29.000575 PG 3 WC Optics SC Optics GA 779TE UT WOS:000189316100015 PM 15035475 ER PT J AU Maleki, L Matsko, AB Savchenkov, AA Ilchenko, VS AF Maleki, L Matsko, AB Savchenkov, AA Ilchenko, VS TI Tunable delay line with interacting whispering-gallery-mode resonators SO OPTICS LETTERS LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; RING-RESONATOR; SLOW; SYSTEMS AB We theoretically study a parallel configuration of two interacting whispering-gallery-mode optical resonators and show a narrowband modal structure as a basis for a widely tunable delay line. For the optimum coupling configuration the system can possess an unusually narrow spectral feature with a much narrower bandwidth than the loaded bandwidth of each individual resonator. The effect has a direct analogy with the phenomenon of electromagnetically induced transparency in quantum systems for which the interference of spontaneous emission results in ultranarrow resonances. (C) 2004 Optical Society of America. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Maleki, L (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM andrey.matsko@jpl.nasa.gov RI Matsko, Andrey/A-1272-2007 NR 17 TC 162 Z9 164 U1 0 U2 35 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAR 15 PY 2004 VL 29 IS 6 BP 626 EP 628 DI 10.1364/OL.29.000626 PG 3 WC Optics SC Optics GA 779TE UT WOS:000189316100032 PM 15035492 ER PT J AU Strahan, SE Douglass, AR AF Strahan, SE Douglass, AR TI Evaluating the credibility of transport processes in simulations of ozone recovery using the Global Modeling Initiative three-dimensional model SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE stratospheric model; process evaluation; transport ID POLAR VORTEX; STRATOSPHERE; CH4; VALIDATION; CHEMISTRY; TRACER; UARS AB [1] The Global Modeling Initiative (GMI) has integrated two 36-year simulations of an ozone recovery scenario with an offline chemistry and transport model using two different meteorological inputs. Physically based diagnostics, derived from satellite and aircraft data sets, are described and then used to evaluate the realism of temperature and transport processes in the simulations. Processes evaluated include barrier formation in the subtropics and polar regions, and extratropical wave-driven transport. Some diagnostics are especially relevant to simulation of lower stratospheric ozone, but most are applicable to any stratospheric simulation. The global temperature evaluation, which is relevant to gas phase chemical reactions, showed that both sets of meteorological fields have near climatological values at all latitudes and seasons at 30 hPa and below. Both simulations showed weakness in upper stratospheric wave driving. The simulation using input from a general circulation model (GMI(GCM)) showed a very good residual circulation in the tropics and Northern Hemisphere. The simulation with input from a data assimilation system (GMI(DAS)) performed better in the midlatitudes than it did at high latitudes. Neither simulation forms a realistic barrier at the vortex edge, leading to uncertainty in the fate of ozone-depleted vortex air. Overall, tracer transport in the offline GMI(GCM) has greater fidelity throughout the stratosphere than it does in the GMI(DAS) . C1 Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Strahan, SE (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA. EM strahan@code916.gsfc.nasa.gov; anne.r.douglass@nasa.gov RI Douglass, Anne/D-4655-2012; Strahan, Susan/H-1965-2012 NR 27 TC 0 Z9 0 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 13 PY 2004 VL 109 IS D5 AR D05110 DI 10.1029/2003JD004238 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806KS UT WOS:000220433400008 ER PT J AU Tuck, AF Hovde, SJ Kelly, KK Reid, SJ Richard, EC Atlas, EL Donnelly, SG Stroud, VR Cziczo, DJ Murphy, DM Thomson, DS Elkins, JW Moore, FL Ray, EA Mahoney, MJ Friedl, RR AF Tuck, AF Hovde, SJ Kelly, KK Reid, SJ Richard, EC Atlas, EL Donnelly, SG Stroud, VR Cziczo, DJ Murphy, DM Thomson, DS Elkins, JW Moore, FL Ray, EA Mahoney, MJ Friedl, RR TI Horizontal variability 1-2 km below the tropical tropopause SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE tropical; troposphere; composition ID UPPER-TROPOSPHERIC HUMIDITY; IN-SITU MEASUREMENTS; LOWER STRATOSPHERE; WATER-VAPOR; AIRCRAFT OBSERVATIONS; OZONE; SPECTROMETER; OZONESONDES; SIMULATIONS; CONVECTION AB [1] Two long meridional flights of the WB57F high-altitude aircraft 1-2 km below the tropical tropopause are examined for ozone and total water variability in the context of a large suite of tracers having lifetimes ranging from 10(-2) to 10(3) years, together with mass spectra of individual aerosol particles. It is concluded that local correlations are predominant; contributing processes to the maintenance of the composition are marine convection, continental convection, in situ chemical production, biomass burning, downward transport from the stratosphere and recirculation. C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Natl Sci Fdn, Climate Dynam Program, Washington, DC 20550 USA. Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Tuck, AF (reprint author), NOAA, Aeron Lab, Boulder, CO 80305 USA. EM atuck@al.noaa.gov; hovde@al.noaa.gov; kkelly@al.noaa.gov; sreid@nsf.gov; erik.c.richard@noaa.gov; eatlas@rsmas.miami.edu; sdonnell@fhsu.edu; fridd@acd.ucar.edu; djcziczo@al.noaa.gov; murphyd@al.noaa.gov; james.w.elkins@noaa.gov; fred.moore@noaa.gov; eray@al.noaa.gov; michael.j.mahoney@jpl.nasa.gov; rfriedl@jpl.nasa.gov RI Tuck, Adrian/F-6024-2011; Murphy, Daniel/J-4357-2012; Ray, Eric/D-5941-2013; Atlas, Elliot/J-8171-2015 OI Tuck, Adrian/0000-0002-2074-0538; Murphy, Daniel/0000-0002-8091-7235; Ray, Eric/0000-0001-8727-9849; NR 28 TC 13 Z9 13 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 13 PY 2004 VL 109 IS D5 AR D05310 DI 10.1029/2003JD003942 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806KS UT WOS:000220433400005 ER PT J AU Chua, D Parks, G Brittnacher, M Germany, G Spann, J AF Chua, D Parks, G Brittnacher, M Germany, G Spann, J TI Auroral substorm timescales: IMF and seasonal variations SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE substorms; timescales; conjugacy; season; aurora ID INTERPLANETARY MAGNETIC-FIELD; PLASMA SHEET DYNAMICS; MAGNETOSPHERIC SUBSTORMS; ELECTRON-PRECIPITATION; GEOMAGNETIC-ACTIVITY; SOLAR-WIND; ONSET; PSEUDOBREAKUPS; IONOSPHERE; SIGNATURES AB [1] The timescales and phases of auroral substorm activity are quantified in this study using the hemispheric power computed from Polar Ultraviolet Imager (UVI) observations. With this approach we are able to determine substorm phase self consistently from the UVI optical measurements without needing any ancillary metrics for auroral activity. This technique also allows us to combine a quantitative measurement of substorm timescales with the qualitative description of auroral morphology during each event. We show how the characteristics of substorms vary with IMF B-Z orientation and season for several hundred substorm events. Substorm intensity, as measured by the rate of energy deposition by electron precipitation, exhibits greater variation with IMF B-Z orientation than with season. The timescale of substorm expansion shows comparable variation with both IMF B-Z orientation and season. On the other hand, substorm recovery times vary more strongly with season than with IMF B-Z direction. The recovery time for substorm activity is well ordered by whether or not the nightside auroral region is sunlit: substorms occurring in the winter and equinox periods have similar recovery timescales which are both roughly a factor of two longer than that for summer when the auroral oval is sunlit. However, IMF B-Z orientation is shown to have a strong modulating effect on both substorm expansion and recovery timescales during the summer. The winter-summer asymmetries in the aurora described by previous studies are more completely explained by the seasonal variations of substorm recovery timescales characterized in this work. Our results support the hypothesis that the ionosphere plays an active role in governing the dynamics of the aurora. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Washington, Dept Earth & Space Sci, Seattle, WA 98195 USA. Univ Alabama, CSPAR, Huntsville, AL 35899 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Chua, D (reprint author), USN, Res Lab, Code 7607, Washington, DC 20375 USA. EM dchua@ssd5.nrl.navy.mil NR 47 TC 12 Z9 12 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 13 PY 2004 VL 109 IS A3 AR A03207 DI 10.1029/2003JA009951 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 806LC UT WOS:000220434400001 ER PT J AU Song, YT Zlotnicki, V AF Song, YT Zlotnicki, V TI Ocean bottom pressure waves predicted in the tropical Pacific SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID EASTERN EQUATORIAL PACIFIC; GENERAL-CIRCULATION; SATELLITE ALTIMETRY; LONG WAVES; SEA-LEVEL; MODEL; VARIABILITY; TOPOGRAPHY; CURRENTS; MOMENTUM AB Using a mass-conserving (non-Boussinesq) Pacific Ocean model and TOPEX/POSEIDON sea-surface height measurements, we document previously unreported bottom pressure waves (BPWs), associated with large-amplitude eddies (vortices) both north and south of the Equator. The bottom pressure signals, defined as the vertically integrated water-mass anomalies, are found to propagate westward across the Pacific Ocean with an approximate 4-mbar amplitude (1 mbar = 100 Newton/m(2), approximately equivalent to 1 cm of sea surface height), continuously interacting with topographic features. Their wavelength is about 1100 kilometers, phase speed is about 0.5 m/s, and period is about 30-days, all consistent with the known properties of tropical instability waves (TIWs). These results suggest that the constantly evolving tropical instability eddies might have strong bottom pressure signals, therefore, likely alias the U.S.-German Gravity Recovery and Climate Experiment (GRACE) measurements, which have a monthly-sampling period. C1 CALTECH, Jet Prop Lab, Div Earth & Space Sci, Pasadena, CA 91009 USA. RP Song, YT (reprint author), CALTECH, Jet Prop Lab, Div Earth & Space Sci, 4800 Oak Grove Dr, Pasadena, CA 91009 USA. EM song@pacific.jpl.nasa.gov NR 36 TC 11 Z9 11 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 12 PY 2004 VL 31 IS 5 AR L05306 DI 10.1029/2003GL018980 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 806KL UT WOS:000220432700002 ER PT J AU Vinoj, V Babu, SS Satheesh, SK Moorthy, KK Kaufman, YJ AF Vinoj, V Babu, SS Satheesh, SK Moorthy, KK Kaufman, YJ TI Radiative forcing by aerosols over the Bay of Bengal region derived from shipborne, island-based, and satellite (Moderate-Resolution Imaging Spectroradiometer) observations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE aerosols; radiative forcing; atmosphere ID TROPICAL INDIAN-OCEAN; SPECTRAL OPTICAL DEPTHS; ARABIAN SEA; TROPOSPHERIC AEROSOL; SUN PHOTOMETER; BLACK CARBON; ANTHROPOGENIC AEROSOLS; SIZE DISTRIBUTIONS; SULFATE AEROSOLS; COASTAL STATION AB Measurements of spectral aerosol optical depths (AODs) were made over the Bay of Bengal region (adjacent to the Indian landmass) on board the oceanographic research vessel Sagar Kanya during February 2003. Simultaneous measurements of spectral AODs and mass concentrations of the composite aerosols and aerosol black carbon (BC) were made at an island location, Port Blair (11.63degreesN, 92.71degreesE), also in the Bay of Bengal. At the cruise locations the AODs were in the range of similar to0.3-0.6 at 500 nm (with a mean value of 0.41 +/- 0.14) and Angstrom wavelength exponent of similar to1.1 +/- 0.1; while at Port Blair the AODs were in the range of 0.11-0.48 at 500 nm and Angstrom wavelength exponent of 0.98 +/- 0.07. Aerosol BC constituted 5.8 +/- 0.6% of the composite aerosol mass concentration with a single-scattering albedo of similar to0.88, indicating the presence of a significant amount of submicron absorbing aerosols. Comparisons of AODs measured at Port Blair during cruise 188 and an earlier cruise (cruise 161B) during March 2001 (over the Bay of Bengal, Arabian Sea, and Indian Ocean) with those derived from Moderate-Resolution Imaging Spectroradiometer (MODIS) (on board the TERRA platform) showed excellent agreement with a mean difference of similar to0.01 and a root-mean-square difference of similar to0.03. Regionally averaged aerosol (net) forcing over the Bay of Bengal was in the range -15 to -24 W m(-2) at the surface and -2 to -4 W m(-2) at the top of the atmosphere in February 2003; these values were smaller in magnitude than those observed over this region during March 2001 and larger than that observed over the Arabian Sea and the Indian Ocean. The resulting atmospheric heating due to aerosol absorption was similar to0.5degreesK/d. C1 Indian Inst Sci, Ctr Atmospher & Ocean Sci, Bangalore 560012, Karnataka, India. Vikram Sarabhai Space Ctr, Space Phys Lab, Thiruvananthapuram 695022, Kerala, India. NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. RP Vinoj, V (reprint author), Indian Inst Sci, Ctr Atmospher & Ocean Sci, Bangalore 560012, Karnataka, India. EM satheesh@caos.iisc.ernet.in RI Vinoj, V./C-3241-2008 OI Vinoj, V./0000-0001-8573-6073 NR 62 TC 67 Z9 68 U1 2 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 12 PY 2004 VL 109 IS D5 AR D05203 DI 10.1029/2003JD004329 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806KR UT WOS:000220433300004 ER PT J AU Rigler, EJ Baker, DN Weigel, RS Vassiliadis, D Klimas, AJ AF Rigler, EJ Baker, DN Weigel, RS Vassiliadis, D Klimas, AJ TI Adaptive linear prediction of radiation belt electrons using the Kalman filter SO SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS LA English DT Article DE Kalman filter; electron radiation belt; adaptive system identification ID GROUND MAGNETIC-FIELDS; SOLAR-WIND CONTROL; GEOMAGNETIC-ACTIVITY; SPACE WEATHER; SEMIANNUAL VARIATION; IMPULSE-RESPONSE; MAGNETOSPHERE; SAMPEX; ORBIT AB [ 1] Prior studies have examined the time-stationary ( and quasi-stationary) dynamic response of relativistic electrons in the Earth's outer radiation belt to changes in solar wind bulk speed using linear prediction filters [ Baker et al., 1990; Vassiliadis et al., 2002]. For this study, we have implemented an adaptive system identification scheme, based on the Kalman filter with process noise, to determine optimal time-dependent electron response functions. The nonlinear dynamic response of the radiation belts can then be tracked in time by recursively updating the optimal linear filter coefficients as new observations become available. We demonstrate a significant improvement in zero-time-lag electron log-flux "predictions'' relative to models that are based on time-stationary linear prediction filters, while incurring only a slight increase in computational complexity. We conclude by discussing modifications necessary for an operational specification and forecast model, including the assimilation of real-time data, more sophisticated model structures, and a more practical gridded description of the radiation belt state. C1 Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA. NASA, Univ Space Res Assoc, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Rigler, EJ (reprint author), Univ Colorado, Atmospher & Space Phys Lab, 1234 Innovat Dr, Boulder, CO 80303 USA. EM jrigler@colorado.edu NR 33 TC 18 Z9 19 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 1542-7390 J9 SPACE WEATHER JI Space Weather PD MAR 12 PY 2004 VL 2 IS 3 AR UNSP S03003 DI 10.1029/2003SW000036 PG 9 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 908AJ UT WOS:000227759200001 ER PT J AU Bera, D Kuiry, SC McCutchen, M Kruize, A Heinrich, H Meyyappan, M Seal, S AF Bera, D Kuiry, SC McCutchen, M Kruize, A Heinrich, H Meyyappan, M Seal, S TI In-situ synthesis of palladium nanoparticles-filled carbon nanotubes using arc-discharge in solution SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ELECTRIC-ARC; WATER; GROWTH; CARBIDE; ONIONS AB A unique, simple, inexpensive and one-step synthesis route of carbon nanotubes (CNT) supported palladium nanoparticles using a simplified arc-discharge in solution is reported. Palladium nanoparticles with 3 nm diameter were found to form during reduction of palladium tetra-chloro-square-planar complex. Pd-nanoparticles were simultaneously encapsulated in CNTs during the rolling of graphene sheets in the arc-discharge process. Energy Dispersive Spectroscopy suggests no functionalization of chlorine to the sidewall of CNTs. Study of High Resolution Transmission Electron microscopy supports the scroll mechanism for CNT formation. (C) 2004 Elsevier B.V. All rights reserved. C1 Univ Cent Florida, Adv Mat Proc & Analysis Ctr, Orlando, FL 32816 USA. Univ Groningen, Mat Sci Grp, Dept Appl Phys, NL-9747 AG Groningen, Netherlands. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Univ Cent Florida, Adv Mat Proc & Analysis Ctr, Eng 1,381,400 Cent Florida Blvd, Orlando, FL 32816 USA. EM de451440@pegasus.cc.ucf.edu; sseal@pegasus.cc.ucf.edu NR 34 TC 62 Z9 65 U1 7 U2 23 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 EI 1873-4448 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD MAR 11 PY 2004 VL 386 IS 4-6 BP 364 EP 368 DI 10.1016/j.cplett.2004.01.082 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 801VZ UT WOS:000220124700026 ER PT J AU Mickley, LJ Jacob, DJ Field, BD Rind, D AF Mickley, LJ Jacob, DJ Field, BD Rind, D TI Climate response to the increase in tropospheric ozone since preindustrial times: A comparison between ozone and equivalent CO2 forcings SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE tropospheric ozone; climate change; stratospheric ozone ID GENERAL-CIRCULATION MODEL; GODDARD-INSTITUTE; GREENHOUSE-GAS; SENSITIVITY; CHEMISTRY; SPACE; RECOMMENDATIONS; SIMULATION; RECOVERY; TRENDS AB We examine the characteristics of the climate response to anthropogenic changes in tropospheric ozone. Using a general circulation model, we have carried out a pair of equilibrium climate simulations with realistic present-day and preindustrial ozone distributions. We find that the instantaneous radiative forcing of 0.49 W m(-2) due to the increase in tropospheric ozone since preindustrial times results in an increase in global mean surface temperature of 0.28degreesC. The increase is nearly 0.4degreesC in the Northern Hemisphere and about 0.2degreesC in the Southern Hemisphere. The largest increases (>0.8degreesC) are downwind of Europe and Asia and over the North American interior in summer. In the lower stratosphere, global mean temperatures decrease by about 0.2degreesC due to the diminished upward flux of radiation at 9.6 mum. The largest stratospheric cooling, up to 1.0degreesC, occurs over high northern latitudes in winter, with possibly important implications for the formation of polar stratospheric clouds. To identify the characteristics of climate forcing unique to tropospheric ozone, we have conducted two additional climate equilibrium simulations: one in which preindustrial tropospheric ozone concentrations were increased everywhere by 18 ppb, producing the same global radiative forcing as present-day ozone but without the heterogeneity; and one in which CO2 was decreased by 25 ppm relative to present day, with ozone at present-day values, to again produce the same global radiative forcing but with the spectral signature of CO2 rather than ozone. In the first simulation (uniform increase of ozone), the global mean surface temperature increases by 0.25degreesC, with an interhemispheric difference of only 0.03degreesC, as compared with nearly 0.2degreesC for the heterogeneous ozone increase. In the second simulation (equivalent CO2), the global mean surface temperature increases by 0.36degreesC, 30% higher than the increase from tropospheric ozone. The stronger surface warming from CO2 is in part because CO2 forcing (obscured by water vapor) is shifted relatively poleward where the positive ice-albedo feedback amplifies the climate response and in part because the magnitude of the CO2 forcing in the midtroposphere is double that of ozone. However, we find that CO2 is far less effective than tropospheric ozone in driving lower stratospheric cooling at high northern latitudes in winter. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Columbia Univ, Goddard Inst Space Studies, New York, NY 10025 USA. RP Mickley, LJ (reprint author), Harvard Univ, Div Engn & Appl Sci, 29 Oxford St, Cambridge, MA 02138 USA. EM ljm@io.harvard.edu; djj@io.harvard.edu; bdf@io.harvard.edu; drind@giss.nasa.gov RI Mickley, Loretta/D-2021-2012 OI Mickley, Loretta/0000-0002-7859-3470 NR 41 TC 38 Z9 39 U1 1 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 11 PY 2004 VL 109 IS D5 AR D05106 DI 10.1029/2003JD003653 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806KQ UT WOS:000220433200001 ER PT J AU Yamauchi, Y Suess, ST Steinberg, JT Sakurai, T AF Yamauchi, Y Suess, ST Steinberg, JT Sakurai, T TI Differential velocity between solar wind protons and alpha particles in pressure balance structures SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE solar wind; Ulysses; plumes; pressure balance structures; Alfven waves ID CORONAL PLUMES; ULYSSES OBSERVATIONS; POLAR PLUMES; HELIUM; HOLES; HYDROGEN; STREAMS; ORIGIN AB Pressure balance structures (PBSs) are a common high-plasma beta feature in high-latitude, high-speed solar wind. They have been proposed as remnants of coronal plumes. If true, they should reflect the observation that plumes are rooted in unipolar magnetic flux concentrations in the photosphere and are heated as oppositely directed flux is advected into and reconnects with the flux concentration. A minimum variance analysis (MVA) of magnetic discontinuities in PBSs showed there is a larger proportion of tangential discontinuities than in the surrounding high-speed wind, supporting the hypothesis that plasmoids or extended current sheets are formed during reconnection at the base of plumes. To further evaluate the character of magnetic field discontinuities in PBSs, differential streaming between alpha particles and protons is analyzed here for the same sample of PBSs used in the MVA. Alpha particles in high-speed wind generally have a higher radial flow speed than protons. However, if the magnetic field is folded back on itself, as in a large-amplitude Alfven wave, alpha particles will locally have a radial flow speed less than protons. This characteristic is used here to distinguish between folded back magnetic fields (which would contain rotational discontinuities) and tangential discontinuities using Ulysses high-latitude, high-speed solar wind data. The analysis indicates that almost all reversals in the radial magnetic field in PBSs are folded back field lines. This is found to also be true outside PBSs, supporting existing results for typical high-speed, high-latitude wind. There remains a small number of cases that appear not to be folds in the magnetic field and which may be flux tubes with both ends rooted in the Sun. The distinct difference in MVA results inside and outside PBSs remains unexplained. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Natl Astron Observ Japan, Tokyo 1818588, Japan. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Yamauchi, Y (reprint author), NASA, George C Marshall Space Flight Ctr, SD 50, Huntsville, AL 35812 USA. EM yamauchi@msfc.nasa.gov; steven.t.suess@nasa.gov; jsteinberg@lanl.gov; sakurai@corona.mtk.nao.ac.jp NR 30 TC 10 Z9 10 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 11 PY 2004 VL 109 IS A3 AR A03104 DI 10.1029/2003JA010274 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 806LB UT WOS:000220434300003 ER PT J AU Nesbitt, FL Cody, RJ Dalton, DA Riffault, V Bedjanian, Y Le Bras, G AF Nesbitt, FL Cody, RJ Dalton, DA Riffault, V Bedjanian, Y Le Bras, G TI Temperature dependence of the rate constant for the reaction F((2)p)+Cl-2 -> FCl+Cl at T=180-360 K SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID ATOM CONCENTRATIONS; KINETICS; SPECTROMETRY; FLUORINE AB The absolute rate constant for the reaction F(P-2) with Cl-2, has been measured using the discharge flow kinetics technique coupled to mass spectrometric detection at T = 180-360 K and l Torr He nominal pressure. Experiments were performed at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD, and Laboratoire de Combustion et Systemes Reactifs-CNRS in Orleans, France. Results of k = (5.7 +/- 0.8) x 10(-11) and (6.2 +/- 0.8) x 10(-11) cm(3) molecule(-1) s(-1) independent of temperature were obtained by each laboratory, respectively. When the results from both laboratories were combined into one data set, an average temperature independent value of k(1) = (6.0 +/- 1.1) x 10(-11) cm(3) molecule(-1) s(-1) was obtained. A very slight positive temperature dependence with k(1)(T) = (6.5 +/- 1.5) x 10(-11) exp{-(20 +/- 60)/T} cm(3) molecule(-1) s(-1) may also be derived from the combined data in the range T = 180-360 K. C1 NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Catholic Univ Amer, Washington, DC 20064 USA. CNRS, Lab Combust & Syst Reactifs, F-45071 Orleans, France. Coppin State Coll, Dept Nat Sci, Baltimore, MD 21216 USA. RP Cody, RJ (reprint author), NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. EM regina.cody@nasa.gov RI RIFFAULT, Veronique/A-2921-2012; Cody, Regina/D-5996-2013 OI RIFFAULT, Veronique/0000-0001-5572-0871; NR 11 TC 4 Z9 4 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD MAR 11 PY 2004 VL 108 IS 10 BP 1726 EP 1730 DI 10.1021/jp030469r PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 801KF UT WOS:000220094100014 ER PT J AU Zhang, PJ AF Zhang, PJ TI The effect of cluster magnetic field on the Sunyaev-Zel'dovich power spectrum SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : clusters : general; galaxies : magnetic fields; cosmic microwave background; cosmology : theory; large-scale structure of Universe ID COSMOLOGICAL PARAMETERS; INTERGALACTIC MEDIUM; GALAXY CLUSTERS; ANALYTIC MODEL; GAS-DENSITY; MATTER; FLUCTUATIONS; SIMULATIONS; ANISOTROPY; EVOLUTION AB Precision measurements of the Sunyaev-Zel'dovich (SZ) effect in upcoming blank sky surveys require theoretical understanding of all physical processes with greater than or similar to10 per cent effects on the SZ power spectrum. We show that the observed cluster magnetic field could reduce the SZ power spectrum by 20 per cent at l similar to 4000, where the SZ power spectrum will be precisely measured by the Sunyaev-Zel'dovich array (SZA) and the Atacama Cosmology Telescope (ACT). At smaller scale, this effect is larger and could reach a factor of several. Such an effect must be considered for an unbiased interpretation of the SZ data. Although the magnetic effect on the SZ power spectrum is very similar to that of radiative cooling, it is measurable by multiband cosmic microwave background polarization measurement. C1 Fermilab Natl Accelerator Lab, NASA, Fermilab Astrophys Grp, Batavia, IL 60510 USA. RP Zhang, PJ (reprint author), Fermilab Natl Accelerator Lab, NASA, Fermilab Astrophys Grp, Box 500, Batavia, IL 60510 USA. EM zhangpj@fnal.gov RI ZHANG, PENGJIE/O-2825-2015 NR 52 TC 9 Z9 9 U1 0 U2 0 PU BLACKWELL PUBLISHING LTD PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAR 11 PY 2004 VL 348 IS 4 BP 1348 EP 1354 DI 10.1111/j.1365-2966.2004.07460.x PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 801HX UT WOS:000220088100023 ER PT J AU Boyd, STP Duncan, RV Holmes, WA AF Boyd, STP Duncan, RV Holmes, WA TI A massive bolometer on the international space station to measure energy deposition by the space radiation environment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE space station radiation environment; massive bolometer; magnetic susceptibility thermometry AB We describe a novel space-based low-temperature radiation detector, the "Particle Heating Detector" (PhD), which was recently selected to be part of the first mission of the Low-Temperature Microgravity Physics Facility, scheduled to fly on the International Space Station in 2008. This massive bolometer will measure total heating induced in an aluminum absorber by the ace radiation environment. The use of paramagnetic alloy thermometers with SQUID readout, giving 0.3 nK/rootHz, resolution, combined with a large-area absorber, will enable the detector to perform high-resolution, real-time measurement of the low energy deposition levels caused by galactic cosmic rays in low-Earth orbit. (C) 2003 Elsevier B.V. All rights reserved. C1 Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Boyd, STP (reprint author), Univ New Mexico, Dept Phys & Astron, 800 Yale Blvd NE, Albuquerque, NM 87131 USA. EM stpboyd@unm.edu NR 4 TC 1 Z9 1 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 167 EP 170 DI 10.1016/j.nima.2003.11.284 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900043 ER PT J AU Vaillancourt, JE Allen, CA Brekosky, R Dosaj, A Galeazzi, M Kelley, R Liu, D McCammon, D Porter, FS Rocks, LE Sanders, WT Stahle, CK AF Vaillancourt, JE Allen, CA Brekosky, R Dosaj, A Galeazzi, M Kelley, R Liu, D McCammon, D Porter, FS Rocks, LE Sanders, WT Stahle, CK TI Large area bismuth absorbers for X-ray microcalorimeters SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY AB Two challenges facing the use of large area (2 mm x 2 mm) bismuth absorbers for microcalorimetry are uncertainties in the heat capacity of bismuth and the effects of lateral heat conduction and position dependence due to the absorber's large size. We have measured the heat capacity of three Bi samples to be 0.3 - 0.6 J K-1 m(-3) at 100 mK. These absorbers also exhibit response variations as phonons created by an X-ray event at an absorber edge will take longer to propagate to the thermometer attachment point than those at the absorber center. This effect may degrade the detector's energy resolution if the propagation time is not very short compared to the thermometer time constant. We show that the response of the largest absorber varies by similar to4% across its area. (C) 2003 Elsevier B.V. All rights reserved. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Miami, Dept Phys, Coral Gables, FL 33146 USA. RP Vaillancourt, JE (reprint author), Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. EM vaillancourt@wisp.physics.wisc.edu RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; OI Porter, Frederick/0000-0002-6374-1119; Vaillancourt, John/0000-0001-8916-1828 NR 5 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 212 EP 215 DI 10.1016/j.nima.2003.11.231 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900055 ER PT J AU Benford, DJ Moseley, SH Staguhn, JG Allen, CA Chervenak, JA Stevenson, TR Hsieh, WT AF Benford, DJ Moseley, SH Staguhn, JG Allen, CA Chervenak, JA Stevenson, TR Hsieh, WT TI Parameter comparison for low-noise Mo/Au TES bolometers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE bolometer; bolometer array; superconductor; transition edge sensor; superconducting bilayer ID SUPERCONDUCTING BOLOMETERS AB We describe a comparative investigation of the parameters of MoAu-bilayer TES bolometers designed for infrared detectors. A set of devices with variations in geometry were fabricated at the NASA/GSFC detector development facility. These detectors have different bilayer aspect ratios (providing differing normal state resistances and current densities), and have varieties of normal metal regions to study the effects of geometry on noise. These normal metal regions are oriented either parallel to or transverse to the direction of current flow, or both. The lowest noise detectors are found to have normal metal regions oriented transversely. For about a dozen different devices, we have measured a large set of parameters by means of a suite of tests. These include complex impedance measurements to derive time constants; IV curves to determine resistance and power; thermal conductance measurements; noise measurements as a function of device resistance; and direct resistance vs. temperature measurements. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. GSFC, SSAI, Greenbelt, MD 20771 USA. RP Benford, DJ (reprint author), NASA, Goddard Space Flight Ctr, Code 685, Greenbelt, MD 20771 USA. EM dominic.benford@nasa.gov RI Benford, Dominic/D-4760-2012 OI Benford, Dominic/0000-0002-9884-4206 NR 6 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 270 EP 273 DI 10.1016/j.nima.2003.11.235 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900072 ER PT J AU Saab, T Apodacas, E Bandler, SR Boyce, K Chervenak, J Figueroa-Feliciano, E Finkbeiner, F Hammock, C Kelley, R Lindeman, M Porter, FS Stahle, CK AF Saab, T Apodacas, E Bandler, SR Boyce, K Chervenak, J Figueroa-Feliciano, E Finkbeiner, F Hammock, C Kelley, R Lindeman, M Porter, FS Stahle, CK TI Characterization and modeling of transition edge sensors for high resolution X-ray calorimeter arrays SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE transition edge sensor; electrical and thermal model; device characterization AB Characterizing and understanding, in detail, the behavior of a Transition Edge Sensor (TES) is required for achieving an energy resolution of 2 eV at 6 keV desired for future X-ray observatory missions. This paper will report on a suite of measurements (e.g. impedance and I-V among others) and simulations that were developed to extract a comprehensive set of TES parameters such as heat capacity, thermal conductivity, and R(T, I), alpha(T, I), and beta(i)(T, I) surfaces. These parameters allow for the study of the TES calorimeter behavior at and beyond the small signal regime. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. QSS Grp, Lanham, MD 20706 USA. Univ Maryland, College Pk, MD 20742 USA. Sci Syst & Applicat, Lanham, MD 20706 USA. RP Saab, T (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM tsaab@milkyway.gsfc.nasa.gov RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 2 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 281 EP 284 DI 10.1016/j.nima.2003.11.238 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900075 ER PT J AU Bandler, SR Figueroa-Feliciano, E Stahle, CK Boyce, K Brekosky, R Chervenak, J Finkbeiner, F Kelley, R Lindeman, M Porter, FS Saab, T AF Bandler, SR Figueroa-Feliciano, E Stahle, CK Boyce, K Brekosky, R Chervenak, J Finkbeiner, F Kelley, R Lindeman, M Porter, FS Saab, T TI Design of transition edge sensor microcalorimeters for optimal performance SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE microcalorimeters; superconductivity AB We have developed a model for transition edge sensors to optimize performance under a variety of different conditions. There are three design trade-offs when engineering a microcalorimeter for a particular application: energy resolution, energy range and maximum count rate. All three are interdependent and are determined by various design parameters such as the detector heat capacity, the sharpness of the transition, and the thermal conductance of the detector to the frame. Our model includes all known sources of intrinsic noise in our calorimeters including the observed broad band excess noise. We will present the results of this model, and its predictions for optimally designed microcalorimeters. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Dept Astron, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Bandler, SR (reprint author), NASA, Goddard Space Flight Ctr, Dept Astron, Code 661, Greenbelt, MD 20771 USA. EM sbandler@milkyway.gsfc.nasa.gov RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 1 TC 5 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 285 EP 288 DI 10.1016/j.nima.2003.11.239 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900076 ER PT J AU Figueroa-Feliciano, E Bandler, S Boyce, K Chervenak, J Finkbeiner, F Kelley, R Lindeman, MA Porter, SF Saab, T Stahle, CK AF Figueroa-Feliciano, E Bandler, S Boyce, K Chervenak, J Finkbeiner, F Kelley, R Lindeman, MA Porter, SF Saab, T Stahle, CK TI Effect of high-flux astronomical sources on the constellation-X microcalorimeter spectrometer SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE calorimeter; TES; design; model; count-rate AB We study the effects of high flux on transition-edge sensors by using a non-linear microcalorimeter model with parameters suitable for the Constellation-X mission. A photon event list was created that simulated the flux and spectrum of the Crab nebula incident on the detector when folded through the Constellation-X optics and filters. Simulations show that even at Crab levels of flux, the Con-X microcalorimeter does not "latch" into the normal state. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Figueroa-Feliciano, E (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Code 662, Greenbelt, MD 20771 USA. EM enectali.figueroa@gsfc.nasa.gov RI Bandler, Simon/A-6258-2010; Kelley, Richard/K-4474-2012; ayyadevara, rajaram/D-1572-2009 OI Bandler, Simon/0000-0002-5112-8106; NR 2 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 303 EP 306 DI 10.1016/j.nima.2003.11.244 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900081 ER PT J AU Staguhn, JG Moseley, SH Benford, BJ Allen, CA Chervenak, JA Stevenson, TR Hsieh, WT AF Staguhn, JG Moseley, SH Benford, BJ Allen, CA Chervenak, JA Stevenson, TR Hsieh, WT TI Approaching the fundamental noise limit in Mo/Au TES bolometers with transverse normal metal bars SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE bolometers; TES; fundamental noise AB Recent efforts in the Transition Edge Sensor (TES) bolometer/calorimeter community have focused on developing detectors whose noise properties are near the fundamental limits. These include the in-band phonon noise, the out-of-band Johnson noise and the 1/f noise. We have investigated the noise performance of Mo/Au-bilayer TES bolometers designed for infrared detectors. These detectors use normal metal regions for the suppression of excess noise, which are oriented either parallel to ("bars") or. transverse to ("stripes") the direction of current flow. Two nearly identical detectors, one with stripes and one, with bars, were fabricated at the NASA/GSFC detector development facility. Significantly lower noise is found with the normal metal regions oriented transversely. We compare the detailed noise measurement and quantitative analysis of the noise level in each device as a function of the detector resistance. Our preliminary result is that the best detector features only moderate excess noise in both the in-band region and in the out-of-band region. This, noise performance is suitable for instruments with multiplexed TES arrays, such as GSFC's FIBRE and SAFIRE. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SSAI, Lanham, MD 20706 USA. Raytheon ITSS, Lanham, MD 20706 USA. RP Staguhn, JG (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM staguhn@stars.gsfc.nasa.gov RI Benford, Dominic/D-4760-2012 OI Benford, Dominic/0000-0002-9884-4206 NR 5 TC 21 Z9 21 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 336 EP 339 DI 10.1016/j.nima.2003.11.261 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900089 ER PT J AU Lindeman, MA Bandler, S Brekosky, RP Chervenak, JA Figueroa-Feliciano, E Finkbeiner, FM Saab, T Stahle, CK AF Lindeman, MA Bandler, S Brekosky, RP Chervenak, JA Figueroa-Feliciano, E Finkbeiner, FM Saab, T Stahle, CK TI Characterization and reduction of noise in Mo/Au transition edge sensors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE transition edge sensor; reduced excess noise; calorimeter; molydenum; gold; bilayer AB We measured noise in a variety of Mo/Au transition-edge sensor (TES) X-ray calorimeters. We investigated the relationship between the noise, bias, and the superconducting phase transition in the TESs. Our square TES calorimeters have achieved very good energy resolutions (2.4 eV at 1.5 keV) but their resolutions have been limited by broadband white excess noise generated by the TES when it is biased in the phase transition. We have recently fabricated Mo/Cu TESs with interdigitated normal metal bars deposited on top of the bilayer. The new TES calorimeters have demonstrated little or no excess noise in the phase transition. These results point the way to development of TES calorimeters with higher energy resolution. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, Greenbelt, MD 20771 USA. RP Lindeman, MA (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM lindeman1@gsfc.nasa.gov RI Bandler, Simon/A-6258-2010 OI Bandler, Simon/0000-0002-5112-8106 NR 1 TC 6 Z9 6 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 348 EP 350 DI 10.1016/j.nima.2003.11.264 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900092 ER PT J AU Porter, FS AF Porter, FS TI Low-temperature detectors in X-ray astronomy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE X-ray astromony; detectors; cryogenic ID MICROCALORIMETER AB The most compelling nature of X-ray astronomy is its richness and scale. Almost every observable object in the sky either naturally emits X-ray radiation or can be observed through X-ray absorption. Current X-ray observatories such as Chandra and XMM-Newton have considerably advanced our understanding of many of these systems by using imaging X-ray cameras and dispersed X-ray spectrometers. However, it is the combination of these two techniques to provide a true broadband, high spectral-resolution, imaging spectrometer that will drive the next revolution in X-ray astronomy. This is where Low-temperature detectors (LTDs) can play a key role but also where the science will continuously challenge the technology. In this brief overview we will explore the constraints that both the science goals and the space environment place on the implementation of LTDs, how current missions such as XQC and Astro-E2 have met these challenges, and where future missions such as Constellation-X, XEUS, and NeXT will drive LTD instruments to a much larger scale. Finally, we will address scaling issues in current LTD detectors and where the LTD community needs to proceed to address both the science goals and expectations of the astrophysics community. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Porter, FS (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM frederick.s.porter@nasa.gov RI Porter, Frederick/D-3501-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 7 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 354 EP 358 DI 10.1016/j.nima.2003.11.266 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900094 ER PT J AU Kelley, RL AF Kelley, RL TI The X-ray microcalorimeter instruments on the Astro-E2 and constellation-X X-ray observatories SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE detectors; calorimeters; microcalorimeters; X-ray; spectometer; instruments; missions ID DETECTOR; MISSION; XRS AB X-ray microcalorimeter arrays are well suited to address key problems in high-energy astrophysics. The Japan/US Astro-E2 mission will deploy a 32-pixel array of microcalorimeters with 6 eV resolution. This mission is scheduled for launch in 2005. Beyond Astro-E2, NASA is formulating the Constellation-X mission to provide a dramatic increase in collecting area with four separate spacecraft each with large area optics and 1 k-pixel calorimeter arrays providing an energy resolution of 2-4 eV. We will describe the microcalorimeter instrumentation on these missions and mention some of their scientific objectives. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Kelley, RL (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. EM ricbard.l.kelley.@milkyway.gsfc.nasa.gov RI Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 NR 7 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 364 EP 367 DI 10.1016/j.nima.2003.11.268 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900096 ER PT J AU Cottam, J Boyce, KR Brown, GV Figueroa-Feliciano, E Kelley, RL Ponce, V Porter, FS Stahle, CK Tillotson, WA AF Cottam, J Boyce, KR Brown, GV Figueroa-Feliciano, E Kelley, RL Ponce, V Porter, FS Stahle, CK Tillotson, WA TI Characterization of the Astro-E2 X-ray spectrometer SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE X-ray detectors; X-ray spectrometers; microcalorimeters AB We present the results of extensive characterization tests of the X-ray Spectrometer (XRS), which will be launched in 2005 as part of the Astro-E2 mission. The XRS will utilize a newly developed 2-D microcalorimeter array of 32 pixels that will provide a resolution of similar to 6 eV over the energy range 0.3-10 keV. The detector is characterized by the energy scale and,energy, resolution, both of which vary with design and operating parameters. We have calibrated the gain scale and energy resolution over a range of operating parameters including bias voltage, temperature, and incident photon flux. We will present the response of the cumulative detector array as well as a measure of the uniformity of the individual pixels. One pixel is physically offset from the array and will be continuously illuminated by a radioactive source in-flight. We will show the accuracy with which this pixel can be used to monitor variations in the focal plane array. Finally we have illuminated the array with a high-energy, continuum source and measured the Hg absorption edges in order to characterize the absorption efficiency of the pixels. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, College Pk, MD 20742 USA. RP Cottam, J (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM jcottam@milkyway.gsfc.nasa.gov RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 0 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 368 EP 371 DI 10.1016/j.nima.2003.11.269 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900097 ER PT J AU Benford, DJ Moseley, SH AF Benford, DJ Moseley, SH TI Cryogenic detectors for infrared astronomy: the Single Aperture Far-InfraRed (SAFIR) Observatory SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE space telescope; far-infrared; bolometer array; cryogenic detectors AB The development of a large, far-infrared telescope in space has taken on a new urgency with breakthroughs in detector technology and recognition of the fundamental importance of the far-infrared spectral region to questions ranging from cosmology to our own Solar system. The Single Aperture Far-InfraRed (SAFIR) Observatory is 10m-class far-infrared observatory that would begin development later in this decade to meet these needs. SAFIR's science goals are driven by the fact that youngest stages of almost all phenomena in the universe are shrouded in absorption by and emission from cool dust that emits strongly in the far-infrared, 20 mum-1 mm. Its operating temperature (4K) and instrument complement would be optimized to reach the natural sky confusion limit in the far-infrared with diffraction-limited performance down to at least the atmospheric cutoff at 40 pm. This would provide a point source sensitivity improvement of several orders of magnitude over that of SIRTF. In order to achieve this, large arrays of detectors with NEPs ranging from a few to a hundred zeptowatts/sqrt(Hz) are needed. Very low temperature superconducting transition edge sensors and far-infrared "photon counting" detectors are critical technologies requiring development for the SAFIR mission. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Benford, DJ (reprint author), NASA, Goddard Space Flight Ctr, Code 685, Greenbelt, MD 20771 USA. EM dominic.benford@nasa.gov RI Benford, Dominic/D-4760-2012 OI Benford, Dominic/0000-0002-9884-4206 NR 4 TC 14 Z9 15 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 379 EP 383 DI 10.1016/j.nima.2003.11.295 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900100 ER PT J AU Staguhn, JG Benford, DJ Moseley, SH Dowell, CD AF Staguhn, JG Benford, DJ Moseley, SH Dowell, CD TI Astronomical results from SHARC-II SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE bolometer array; far-infrared; astronomy; dust emission; galaxies AB The Submillimeter High Angular Resolution Camera (SHARC-II) is a facility instrument for far-infrared (350 mum) imaging at the Caltech Submillimeter Observatory (CSO). With 384 pixels, SHARC-II uses the world's largest bolometer array for astronomical observations. SHARC-II is most efficiently utilized for observations of extended sources and for deep sky surveys. The low 1/f detector noise allows total power measurements without the need to observe an emission free "off position". This is possible because the sky emission can be distinguished from the celestial emission when the array scans over the sky at sufficient' speed. Here we present a representative set of SHARC-II observations, which highlight the capabilities of the instrument. The observations show the submillimeter continuum emission from our own Galactic center, the nearby galaxy M 51, and the gravitationally lensed high-z Cloverleaf galaxy H 1413 + 1143. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SSAI, Lanham, MD 20706 USA. CALTECH, Pasadena, CA 91125 USA. NASA, JPL, Pasadena, CA 91109 USA. RP Staguhn, JG (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM staguhn@stars.gsfc.nasa.gov RI Benford, Dominic/D-4760-2012 OI Benford, Dominic/0000-0002-9884-4206 NR 2 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 384 EP 386 DI 10.1016/j.nima.2003.11.296 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900101 ER PT J AU Benford, DJ Devlin, MJ Dicker, SR Irwin, KD Jewell, PR Klein, J Mason, BS Moseley, HS Norrod, RD Supanich, MP AF Benford, DJ Devlin, MJ Dicker, SR Irwin, KD Jewell, PR Klein, J Mason, BS Moseley, HS Norrod, RD Supanich, MP TI A 90 GHz array for the green bank telescope SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE TES bolometer array; millimeter wave receivers; cryogenics AB We report on the design and construction of an 8 x 8 bolometer array designed to operate at 90 GHz on the new 100 in Green Bank Telescope (GBT). The bolometers are Transition Edge Superconducting (TES) detectors read out using a SQUID multiplexing system. The receiver will be one of the first astronomical instruments to use such detectors. To cool the detectors, we have developed He-3 and He-4 sorption refrigerators that cycle from a two-stage pulse-tube cryocooler. The system has been demonstrated to be robust, to be capable of cycling autonomously, and to provide 15 muW of cooling below 286 mK with a hold time over 70 h. Although modest in size, a combination of the size of GBT and the low noise of the TES detectors will make our receiver one of the most sensitive of its kind. (C) 2003 Elsevier B.V. All rights reserved. C1 Univ Penn, Philadelphia, PA 19104 USA. NIST, Electromagnet Technol Div, Boulder, CO 80305 USA. NRAO Green Bank, Green Bank, WV 24944 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Dicker, SR (reprint author), Univ Penn, 209 S 33rd St, Philadelphia, PA 19104 USA. EM sdicker@hep.upenn.edu RI Benford, Dominic/D-4760-2012; Moseley, Harvey/D-5069-2012; Klein, Jeffrey/E-3295-2013 OI Benford, Dominic/0000-0002-9884-4206; NR 4 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 387 EP 389 DI 10.1016/j.nima.2003.11.341 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900102 ER PT J AU Goldin, A Bock, JJ Lange, AE LeDuc, H Vayonakis, A Zmuidzinas, J AF Goldin, A Bock, JJ Lange, AE LeDuc, H Vayonakis, A Zmuidzinas, J TI Antennas for bolometric focal plane SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE slot antennas; CMB; polarization; TES bolometers AB The future Cosmic Microwave Background (CMB) experiments will require large focal planes with hundreds of bolometric receivers. For CMB detectors, the field of view should be restricted, as even with cryostat cooled liquid helium temperatures a significant deteriorating performance load will be present (Appl. Opt. 41 (2002) 6543). We present a planar antenna for millimeter band produced by lithographical methods only, which, without lens concentrator or a horn, has convenient beamwidth about F/3-F/4. The radiation and impedance characteristics of the antenna were obtained from a moment-method calculation. The measured beammap of the antenna prototype is presented in this paper. (C) 2003 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Pasadena, CA 91125 USA. RP Goldin, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM alexey.goldin@jpl.nasa.gov NR 3 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 390 EP 392 DI 10.1016/j.nima.2003.11.342 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900103 ER PT J AU Terenzi, L Mennella, A Bersanelli, M Mandolesi, N Morgante, G Prina, M Tomasi, M Valenziano, L AF Terenzi, L Mennella, A Bersanelli, M Mandolesi, N Morgante, G Prina, M Tomasi, M Valenziano, L TI Thermal stability in precision cosmology experiments: the Planck LFI case SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE cosmology; cosmic microwave background observation; instrumentation; detectors AB After the great success of NASA's satellite missions COBE and WMAP, the Planck mission represents the third generation of mm-wave instruments designed for space observations of CMB anisotropies. Two instruments, the Low-Frequency Instrument (LFI) and the High-Frequency Instrument (HFI) will produce CMB maps with unprecedented angular resolution, sensitivity and frequency coverage. This ambitious task will be achieved by using low noise HEMT detectors cryogenically cooled at similar to 20 K for the LFI and bolometric detectors cooled at 0.1 K for the HFI; in particular, the LFI is based on pseudo-correlation receivers in which the sky signal is continuously compared to a cryogenic reference load in thermal contact with the HFI 4 K stage. Such high sensitivity in Planck detectors calls for a strict control of systematic effects, which must be kept at muK level in the final maps; this in turn imposes tight requirements on the thermal and electrical stability of the different stages in the instrument. In this paper we discuss a study of the impact of thermal fluctuations at the level of the 20 K cooler cold-end on the Planck-LFI measurements and present some viable solutions that have been adopted to keep the residual systematic error within the required values for Planck-LFI. (C) 2003 Elsevier B.V. All rights reserved. C1 CNR, IASF, Sez Bologna, I-40129 Bologna, Italy. CNR, IASF, Sez Milano, I-20133 Milan, Italy. Univ Milan, I-20133 Milan, Italy. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Terenzi, L (reprint author), CNR, IASF, Sez Bologna, Via Gobetti 101, I-40129 Bologna, Italy. EM terenzi@bo.iasf.cnr.it RI Tomasi, Maurizio/I-1234-2016; OI Tomasi, Maurizio/0000-0002-1448-6131; Morgante, Gianluca/0000-0001-9234-7412; Valenziano, Luca/0000-0002-1170-0104; TERENZI, LUCA/0000-0001-9915-6379 NR 7 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 393 EP 395 DI 10.1016/j.nima.2003.11.343 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900104 ER PT J AU Cuttaia, F Valenziano, L Bersanelli, M Butler, RC D'Arcangelo, O Kettle, D Levin, S Mandolesi, N Mennella, A Morgante, G Morigi, G Roddis, N Simonetto, A Terenzi, L Tomasi, M Villa, F AF Cuttaia, F Valenziano, L Bersanelli, M Butler, RC D'Arcangelo, O Kettle, D Levin, S Mandolesi, N Mennella, A Morgante, G Morigi, G Roddis, N Simonetto, A Terenzi, L Tomasi, M Villa, F TI Analysis of the radiometer-reference load system on board the Planck/LFI instrument SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE cosmology; cosmic microwave background; satellite; Planck; radiometer; blackbody; finite element method ID FREQUENCY INSTRUMENT; DESIGN AB The Low Frequency Instrument aboard the Planck satellite will employ pseudo-correlation radiometers, operating over three broad bands centered at 30, 44, 70GHz. This choice is oriented to maximize the instrumental stability reducing non-white noise effects produced inside the radiometers. The radiometer scheme allows the simultaneous comparison of two input signals, one coming from the telescope and the other coming from a reference blackbody (the "reference load" RL) at a stable temperature near 4 K. In order to minimize non-white noise, typically exhibiting a I If spectrum, the Reference Load temperature must be as close as possible to the sky temperature (about 2.7 K). The accuracy of the measurement is tightly related to the ability of keeping under control and minimizing all systematic effects potentially. perturbing the RL signal, particularly those not easily removable in software during data analysis. A model of the,radiometer and RL system interface, based on the finite elements method, has been developed, together with a detailed thermal modeling, to characterize the physical system and to optimize its performance. The function of the radiometric chain, the modeling and the changes made in the baseline configuration to improve the system performances are described. The impact of systematic effects on the optimized configuration are also quantitatively investigated. (C) 2003 Elsevier B.V. All rights reserved. C1 CNR, IASF, Sez Bologna, I-40129 Bologna, Italy. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. CNR, IFP, I-20125 Milan, Italy. Jodrell Bank, Macclesfield SK11 9DL, Cheshire, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CNR, IASF, Sez Milano, I-20133 Milan, Italy. RP Cuttaia, F (reprint author), CNR, IASF, Sez Bologna, Via P Gobetti 101, I-40129 Bologna, Italy. EM cuttaia@bo.iasf.cnr.it; terenzi@bo.iasf.cnr.it RI Tomasi, Maurizio/I-1234-2016; Butler, Reginald/N-4647-2015; OI Tomasi, Maurizio/0000-0002-1448-6131; Butler, Reginald/0000-0003-4366-5996; Morgante, Gianluca/0000-0001-9234-7412; Cuttaia, Francesco/0000-0001-6608-5017; Valenziano, Luca/0000-0002-1170-0104; Villa, Fabrizio/0000-0003-1798-861X; TERENZI, LUCA/0000-0001-9915-6379 NR 12 TC 6 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 396 EP 401 DI 10.1016/j.nima.2003.11.344 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900105 ER PT J AU Kilbourne, CA AF Kilbourne, CA TI The science and technology of microcalorimeter arrays SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE microcalorimeter arrays; thermal detectors AB I will review the present status and future prospects for arrays of microcalorimeters used for high-resolution photon spectroscopy. The various applications impose different constraints on the array designs, but there are many common physics and engineering issues as well. I will present both the unique and the shared aspects of their design, fabrication, and operation. As we are well into the age of small microcalorimeter arrays, I will present the performance of a variety of functioning arrays. Arrays with more than 1000 pixels are under development; I will report on their progress and on the technical issues associated with arrays of this scale and larger. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Kilbourne, CA (reprint author), NASA, Goddard Space Flight Ctr, Mail Code 662, Greenbelt, MD 20771 USA. EM cak@lheapop.gsfc.nas.gov NR 7 TC 5 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 402 EP 406 DI 10.1016/j.nima.2003.11.345 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900106 ER PT J AU Enss, C Fleischmann, A Bandler, SR Stevenson, TR Seidel, GM AF Enss, C Fleischmann, A Bandler, SR Stevenson, TR Seidel, GM TI Design considerations for arrays of MMCs for X-ray astronomy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE X-ray astronomy; calorimeters; arrays AB There are a number of substantially different ways of fabricating arrays of metallic magnetic calorimeters (MMCs). We discuss different designs and readout schemes and comment on the requirements, advantages and disadvantages of specific MMC arrays. In particular, we address the problems of thermal and inductive cross-talk, thermalization times, heat dissipation, layout and suitable SQUID readout techniques. (C) 2003 Elsevier B.V. All rights reserved. C1 Brown Univ, Dept Phys, Providence, RI 02912 USA. Univ Heidelberg, Kirchhoff Inst Phys, D-69120 Heidelberg, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Enss, C (reprint author), Brown Univ, Dept Phys, Box 1843, Providence, RI 02912 USA. EM Christian.Enss@Brown.edu; Andreas.Fleischmann@kip.uni-heidelberg.de; sbandler@milkyway.gsfc.nasa.gov; Thomas.R.Stevenson@nasa.gov; seidel@physics.brown.edu RI Bandler, Simon/A-6258-2010 OI Bandler, Simon/0000-0002-5112-8106 NR 1 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 407 EP 410 DI 10.1016/j.nima.2003.11.346 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900107 ER PT J AU Lindeman, MA Bandler, S Brekosky, RP Chervenak, JA Figueroa-Feliciano, E Finkbeiner, FM Kelley, RL Saab, T Stahle, CK Talley, DJ AF Lindeman, MA Bandler, S Brekosky, RP Chervenak, JA Figueroa-Feliciano, E Finkbeiner, FM Kelley, RL Saab, T Stahle, CK Talley, DJ TI Performance of compact TES arrays with integrated high-fill-fraction X-ray absorbers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE calorimeter; transition edge sensor; compact array; mushroom absorber; bismuth AB We have recently produced and tested two-dimensional arrays of Mo/Au transition-edge-sensor (TES) calorimeters with Bi/Cu absorbers. The arrays represent a significant step towards meeting the specifications of NASA's Constellation-X mission. The calorimeters are compactly spaced within 5 x 5 arrays of 250 mum square pixels necessary for an angular resolution of 5 arcsec. Lithographically produced absorbers hang over the substrate and wiring between the TESs for high filling fraction and high quantum efficiency. We designed the calorimeters with heat capacities and thermal couplings such that X-rays produce pulses with fall times of approximately 300 mus to allow relatively high count rates with low dead time. We read out up to four of the pixels simultaneously. The arrays demonstrated very good energy resolution (5 eV at 1.5 keV and 7 eV at 6 keV) and little crosstalk between neighboring pixels. Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, Greenbelt, MD 20771 USA. RP Talley, DJ (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM lindeman@lheapop.gsfc.nasa.gov; sbandler@milkyway.gsfc.nasa.gov; Regis.Brekosky@gsfc.nasa.gov; jcherven@pop500.gsfc.nasa.gov; Enectali.Figueroa-1@nasa.gov; fmf@milkyway.gsfc.nasa.gov; Richard.L.Kelley@nasa.gov; tsaab@milkyway.gsfc.nasa.gov; Caroline.K.Stahle@nasa.gov RI Bandler, Simon/A-6258-2010; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; NR 1 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 411 EP 413 DI 10.1016/j.nima.2003.11.347 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900108 ER PT J AU Moseley, SH Allen, CA Benford, D Dowell, CD Harper, DA Phillips, TG Silverberg, RF Staguhn, J AF Moseley, SH Allen, CA Benford, D Dowell, CD Harper, DA Phillips, TG Silverberg, RF Staguhn, J TI The design and performance of the 384-element imaging submillimeter detector arrays for HAWC and SHARC II SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE cryogenic detectors; array detectors; submillimeter imaging; far-infrared AB We report on the performance of the SHARC II detector, a 12 x 32 array of ion implanted Si pop-up bolometers. This 384 element detector array was built as a prototype for the High Angular Resolution Widefield Camera for the Stratospheric Observatory for Infrared Astronomy. We will discuss the design process, the characterization of the detectors, and the performance of the array in the SHARC II instrument. SHARC II is now a facility instrument on the Caltech Submillimeter Observatory, providing background-limited imaging at 350 and 450 mum. (C) 2003 Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Dept Phys, Pasadena, CA 91125 USA. Univ Chicago, Chicago, IL 60637 USA. RP Moseley, SH (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM moseley@stars.gsfc.nasa.gov; christine.a.allen@nasa.gov; Dominic.J.Benford@nasa.gov; Robert.F.Silverberg@nasa.gov RI Benford, Dominic/D-4760-2012; Moseley, Harvey/D-5069-2012 OI Benford, Dominic/0000-0002-9884-4206; NR 6 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 417 EP 420 DI 10.1016/j.nima.2003.11.349 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900110 ER PT J AU Silverberg, RF Ali, S Bier, A Campano, B Chen, TC Cheng, ES Cottingham, DA Crawford, TM Downes, T Finkbeiner, FM Fixsen, DJ Logan, D Meyer, SS O'Dell, C Perera, T Sharp, EH Timbie, PT Wilson, GW AF Silverberg, RF Ali, S Bier, A Campano, B Chen, TC Cheng, ES Cottingham, DA Crawford, TM Downes, T Finkbeiner, FM Fixsen, DJ Logan, D Meyer, SS O'Dell, C Perera, T Sharp, EH Timbie, PT Wilson, GW TI A bolometer array for the spectral energy distribution (SPEED) camera SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE bolometer; millimeter; telescope ID GALAXIES AB The Spectral Energy Distribution (SPEED) Camera is being developed to study the spectral energy distributions of high redshift galaxies. Its initial use will be on the Heinrich Hertz Telescope and eventually on the Large Millimeter Telescope. SPEED requires a small cryogenic detector array of 2 x 2 pixels with each pixel having four frequency bands in the 150-375 GHz range. Here we describe the development of the detector array of these high-efficiency Frequency Selective Bolometers (FSB). The FSB design provides the multi-pixel, multi-spectral band capability required for SPEED in a compact stackable array. The SPEED bolometers will use proximity effect superconducting transition edge sensors as their temperature-sensing element, allowing for higher levels of electronic multiplexing in future applications. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Global Sci & Technol, Greenbelt, MD 20771 USA. Conceptual Analyt, Glenn Dale, MD 20769 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. SSAI, Lanham, MD 20706 USA. Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. RP Silverberg, RF (reprint author), NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. EM Robert.F.Silverberg@nasa.gov; ali@wisp.physics.wisc.edu; tchen@stars.gsfc.nasa.gov; fmf@milkyway.gsfc.nasa.gov; fixsen@stars.gsfc.nasa.gov; timbie@wisp.physics.wisc.edu NR 7 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 421 EP 423 DI 10.1016/j.nima.2003.11.350 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900111 ER PT J AU Brekosky, RP Allen, CA Galeazzi, M Gygax, JD Isenburg, H Kelley, RL McCammon, D McClanahan, RA Porter, FS Stahle, CK Szymkowiak, AE AF Brekosky, RP Allen, CA Galeazzi, M Gygax, JD Isenburg, H Kelley, RL McCammon, D McClanahan, RA Porter, FS Stahle, CK Szymkowiak, AE TI Fabrication process responsible for fundamentally improving Silicon X-ray microcalorimeter arrays SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE XRS; Astro-E2; fabrication; microcalorimeter; array; pixel AB We have developed an improved microcalorimeter array that will be used on the AstroE-2 satellite mission. The 6 x 6 array consists of a grid of 36 suspended pixels. Each 1.5 mum thick pixel has an ion-implanted thermometer, four thermal links (support beams), and four X-ray absorber support tabs. Improvements in Silicon micro-machining capabilities and the availability of custom Silicon-on-Insulator (Sol) wafers has enabled us to precisely control pixel geometry, lead widths, and develop a more compact array. Knowing the silicon thickness, we can calculate a precise implant dose for the thermometer. Using a high-temperature anneal, we can uniformly diffuse the implant throughout the depth of the top layer of the Sol wafer. Defining the length, width, and thickness of the support beams, we can control the thermal conductance of the pixel. Advancements in polymer-photo resists have enabled us to develop a new absorber support tab attachment scheme resulting in more controlled heat dissipation from the absorber to the thermometer on the pixel. An overview of fabrication improvements focusing on these topics will be discussed. (C) 2003 Elsevier B.V. All rights reserved. C1 Swales Aerosp, Beltsville, MD 20705 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Miami, Dept Phys, Coral Gables, FL 33146 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. RP Brekosky, RP (reprint author), Swales Aerosp, Beltsville, MD 20705 USA. EM regis.brekosky@gsfc.nasa.gov RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Porter, Frederick/0000-0002-6374-1119; NR 1 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 439 EP 442 DI 10.1016/j.nima.2003.11.358 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900116 ER PT J AU Chen, TC Bier, A Campano, BA Cottingham, DA Finkbeiner, FM O'Dell, C Sharp, E Silverberg, RF Wilson, G AF Chen, TC Bier, A Campano, BA Cottingham, DA Finkbeiner, FM O'Dell, C Sharp, E Silverberg, RF Wilson, G TI Development of molybdenum-gold proximity bilayers as transition edge sensors for the SPEED camera SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE bolometers; transition edge sensors; frequency selective bolometers; fabrication; cryogenic AB Bolometers are being developed with thermistor elements using Mo/Au proximity bilayers as superconducting transition edge. sensor. These bolometers will be used by the Spectral Energy Distribution camera which is being developed to study the spectral energy distribution of high redshift galaxies. The bolometers are fabricated on 11 x 11 mm(2) suspended 0.5 mum thick low-stress LPCVD silicon nitride films supported by 475 mum thick silicon frames. To obtain the required thermal conductivity, the films are perforated to form central disks suspended by thin legs. Here we discuss the design, fabrication process, and current test results of these bolometers. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, GSFC, SSAI, Lanham, MD USA. Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Chen, TC (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM tchen@stars.gsfc.nasa.gov NR 1 TC 2 Z9 2 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 446 EP 448 DI 10.1016/j.nima.2003.11.368 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900118 ER PT J AU Chervenak, JA Finkbeiner, FM Stevenson, TR Talley, DJ Brekosky, RP Bandler, SR Figueroa-Feliciano, E Lindeman, MA Kelley, RL Saab, T Stahle, CK AF Chervenak, JA Finkbeiner, FM Stevenson, TR Talley, DJ Brekosky, RP Bandler, SR Figueroa-Feliciano, E Lindeman, MA Kelley, RL Saab, T Stahle, CK TI Fabrication of transition edge sensor X-ray microcalorimeters for constellation-X SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE X-ray detector; transition edge sensor; bilayer AB NASA's Constellation-X (Con-X) mission is a driver for advancing low-temperature detector technologies, requiring 1000-pixel two-dimensional arrays with >95% filling fraction and quantum efficiency at 6 keV and better than 4 eV energy resolution for 1-10 keV photons. We describe a robust transition edge sensor fabrication process that can produce detector arrays with integrated absorbers approaching the specifications of Con-X. We address issues such as the methods of superconducting bilayer deposition, detector geometry definition, and absorber interface. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Chervenak, JA (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM james.chervenak@nasa.gov RI Bandler, Simon/A-6258-2010; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; NR 7 TC 19 Z9 20 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 460 EP 462 DI 10.1016/j.nima.2003.11.372 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900122 ER PT J AU Finkbeiner, FM Adams, C Apodaca, E Chervenak, JA Fischer, J Doan, N Li, MJ Stahle, CK Brekosky, RP Bandler, SR Figueroa-Feliciano, E Lindeman, MA Kelley, RL Saab, T Talley, DJ AF Finkbeiner, FM Adams, C Apodaca, E Chervenak, JA Fischer, J Doan, N Li, MJ Stahle, CK Brekosky, RP Bandler, SR Figueroa-Feliciano, E Lindeman, MA Kelley, RL Saab, T Talley, DJ TI Development of ultra-low impedance through-wafer micro-vias SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE through-wafer micro-via; high-aspect ratio etching; PPR electro-deposition; cryogenic temperatures AB Concurrent with our microcalorimeter array fabrication for Constellation-X technology development, we are developing ultra-low impedance Through-Wafer Micro-Vias (TWMV) as electrical interconnects for superconducting circuits. The TWMV will enable the electrical contacts of each detector to be routed to contacts on the backside of the array. There, they can be bump-bonded to a wiring fan-out board which interfaces with the front-end Superconducting Quantum Interference Device readout. We are concentrating our developmental efforts on ultra-low impedance copper and superconducting aluminum TWMV in 300-400 micron thick silicon wafers. For both schemes, a periodic pulse-reverse electroplating process is used to fill or coat micron-scale through-wafer holes of aspect ratios up to 20. Here we discuss the design, fabrication process, and recent electro-mechanical test results of Al and Cu TWMV at room and cryogenic temperatures. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, GSFC, SSAI, Lanham, MD USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, GSFC, QSS, Lanham, MD USA. AlumiPlate Inc, Minneapolis, MN 55433 USA. Swales Aerosp, Beltsville, MD USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Finkbeiner, FM (reprint author), NASA, GSFC, SSAI, Code 662, Lanham, MD USA. EM fmf@lheapop.gsfc.nasa.gov RI Bandler, Simon/A-6258-2010; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; NR 3 TC 7 Z9 7 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 463 EP 465 DI 10.1016/j.nima.2003.11.373 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900123 ER PT J AU Stahle, CK Allen, CA Boyce, KR Brekosky, RP Brown, GV Cottam, J Figueroa-Feliciano, E Galeazzi, M Gygax, JD Jacobson, MB Kelley, RL Liu, D McCammon, D McClanahan, RA Moseley, SH Porter, FS Rocks, LE Szymkowiak, AE Vaillancourt, JE AF Stahle, CK Allen, CA Boyce, KR Brekosky, RP Brown, GV Cottam, J Figueroa-Feliciano, E Galeazzi, M Gygax, JD Jacobson, MB Kelley, RL Liu, D McCammon, D McClanahan, RA Moseley, SH Porter, FS Rocks, LE Szymkowiak, AE Vaillancourt, JE TI The next-generation microcalorimeter array of XRS on astro-E2 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE microcalorimeter array; thermal detectors AB The square-format 32-pixel microcalorimeter array at the focal plane of the high-resolution X-ray spectrometer on the Astro-E2 X-ray Observatory is the first of a new generation of silicon-based microcalorimeters. This array has numerous advantages over its predecessor, the bilinear array that was launched on Astro-E. Foremost among its benefits are: (1) the energy resolution is improved by a factor of two at 6 keV (now 6 eV FWHM), (2) the thermal time constant is a factor of two faster, and (3) each pixel has a Gaussian line response. We will discuss the design changes that have led to these and other advantages. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Swales Aerosp, Beltsville, MD 20705 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Miami, Dept Phys, Coral Gables, FL 33146 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. RP Stahle, CK (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM cak@lheapop.gsfc.nasa.gov RI Porter, Frederick/D-3501-2012; Moseley, Harvey/D-5069-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009; OI Porter, Frederick/0000-0002-6374-1119; Vaillancourt, John/0000-0001-8916-1828 NR 5 TC 28 Z9 28 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 466 EP 468 DI 10.1016/j.nima.2003.11.374 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900124 ER PT J AU Galeazzi, M Boyce, KR Brown, GV Chen, C Cottam, J Figueroa-Feliciano, E Jacobson, MB Kelley, RL Liu, D McCammon, D Porter, FS Rocks, LE Stahle, CK Szymkowiak, AE Vaillancourt, JE AF Galeazzi, M Boyce, KR Brown, GV Chen, C Cottam, J Figueroa-Feliciano, E Jacobson, MB Kelley, RL Liu, D McCammon, D Porter, FS Rocks, LE Stahle, CK Szymkowiak, AE Vaillancourt, JE TI Design of the second generation XRS detector SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE XRS detector; microcalorimeter; absorber decoupling ID MODEL AB Microcalorimeter performance is limited by non-ideal effects that were not included in the standard theory of bolometers and microcalorimeters developed 20 years ago by Mather (Appl. Opt. 21 (1982) 1125). These include the hot-electron effect, absorber decoupling, thermometer non-ohmic behavior, and all related extra noise sources. Models that include these effects have been developed and can be used to optimize the design of microcalorimeters for best performance. The design of the array for the XRS detector on the Astro-E2 satellite was completely optimized based on the required performance and on the characteristics of the materials used. The characteristic heat capacity and thermal conductivity Of all the detector components have been measured and the values have been used as input to the models to design the detector geometry for best performance. Mechanical modeling has also been carried out in parallel to ensure the mechanical integrity of the microcalorimeter. We report here the analysis involved in the optimization of the detectors, and the comparison between modeled and measured performance. (C) 2003 Elsevier B.V. All rights reserved. C1 Univ Miami, Dept Phys, Coral Gables, FL 33124 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. RP Galeazzi, M (reprint author), Univ Miami, Dept Phys, POB 248046, Coral Gables, FL 33124 USA. EM galeazzi@physics.miami.edu RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 4 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 469 EP 471 DI 10.1016/j.nima.2003.11.375 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900125 ER PT J AU Stahle, CK Boyce, KR Brown, GV Cottam, J Figueroa-Feliciano, E Galeazzi, M Kelley, RL McCammon, D Porter, FS Szymkowiak, AE Tillotson, WA AF Stahle, CK Boyce, KR Brown, GV Cottam, J Figueroa-Feliciano, E Galeazzi, M Kelley, RL McCammon, D Porter, FS Szymkowiak, AE Tillotson, WA TI Cosmic ray effects in microcalorimeter arrays SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE microcalorimeter array; cosmic rays; thermal detectors ID PERFORMANCE; DESIGN AB We have identified signals resulting from cosmic rays and environmental gamma rays depositing energy in the pixels and in the silicon frame of the Astro-E2/X-Ray Spectrometer microcalorimeter array. Coincidences between pixels and between the array and an anti-coincidence detector determined the nature of the events. Pulse shapes and amplitudes from the cosmic ray events helped refine the thermal model of the array chip. We discuss how future arrays can be optimized either for the greatest background rejection or for the highest source count rates. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Miami, Dept Phys, Coral Gables, FL 33146 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. RP Stahle, CK (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM cak@lheapop.gsfc.nasa.gov RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 4 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 472 EP 474 DI 10.1016/j.nima.2003.11.376 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900126 ER PT J AU Yun, M Bock, J Leduc, H Day, P Kim, MJ AF Yun, M Bock, J Leduc, H Day, P Kim, MJ TI Fabrication of antenna-coupled transition edge polarization-sensitive bolometer arrays SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE bolometer; TES; antenna-coupled array AB We have fabricated antenna-coupled superconducting transition edge sensor (TES) arrays for far-infrared and millimeter-wave applications. The advantage of antenna coupling is that the large optical coupling structure required for far-infrared/millimeter wavelengths is not thermally active. The sensor can thus be as small as lithographic techniques permit. By eliminating large absorbers, this technology enables bolometers working at frequencies as low as 30 GHz, covering the entire spectral region of interest for future space-borne studies of cosmic microwave background polarization. We developed a focal plane architecture with dual-polarization sensitivity in a single spectral band, or single-polarization sensitivity in multiple spectral bands. We use TES layers consisting of Al/Ti/Au/Ti thin films and Nb electrical contacts on a low-stress Si3N4 membrane. (C) 2003 Published by Elsevier B.V. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Texas, Dept Elect Engn, Richardson, TX 75083 USA. RP Yun, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM minhee.yun@jpl.nasa.gov RI Kim, Moon/A-2297-2010 NR 5 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 487 EP 489 DI 10.1016/j.nima.2003.11.380 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900130 ER PT J AU Figueroa-Feliciano, E AF Figueroa-Feliciano, E TI Position-sensitive low-temperature detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE calorimeter; STJ; TES; position-sensitive detector ID RESOLUTION; SPECTROSCOPY; ENERGY AB Position-sensitive detectors are under development for various applications. These detectors are well suited for applications where the rate of detected photons is low and large area detectors are desired. They also may be used in applications where the required pixel size is smaller than the smallest single-pixel detectors that can be built today. I will review the present status of this technology as well as the trade-offs inherent in their design. Different approaches to position resolution in a detector will be discussed along with future concepts for very large format arrays. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Figueroa-Feliciano, E (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. EM enectali.figueroa-1@nasa.gov NR 10 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 496 EP 501 DI 10.1016/j.nima.2003.11.297 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900133 ER PT J AU Hammock, C Figueroa-Feliciano, E Apodaca, E Bandler, S Boyce, K Chervenak, J Finkbeiner, F Kelley, R Lindeman, M Porter, S Saab, T Stahle, C AF Hammock, C Figueroa-Feliciano, E Apodaca, E Bandler, S Boyce, K Chervenak, J Finkbeiner, F Kelley, R Lindeman, M Porter, S Saab, T Stahle, C TI position-sensitive transition edge sensor modeling and results SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE X-ray; spectrometer; microcalorimeter; position-sensitive; constellation-X; calorimeter AB We report the latest design and experimental results for a Position-Sensitive Transition-Edge Sensor (POST). The POST is motivated by the desire to achieve a larger field-of-view without increasing the number of readout channels. A POST consists of a one-dimensional array of X-ray absorbers connected on each end to a Transition Edge Sensor (TES). Position differentiation is achieved through a comparison of pulses between the two TESs and X-ray energy is inferred from a sum of the two signals. Optimizing such a device involves studying the available parameter space which includes device properties such as heat capacity and thermal conductivity as well as TES read-out circuitry parameters. We present results for different regimes of operation and the effects on energy resolution, throughput, and position differentiation. Results and implications from a non-linear model developed to study the saturation effects unique to PoSTs are also presented. (C) 2003 Elsevier B.V. All rights reserved. C1 SSAI, Lanham, MD 20706 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. QSS Grp, Lanham, MD 20706 USA. Univ Maryland, College Pk, MD 20742 USA. RP Hammock, C (reprint author), SSAI, Lanham, MD 20706 USA. EM chammock@milkyway.gsfc.nasa.gov RI Bandler, Simon/A-6258-2010; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; NR 3 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 505 EP 507 DI 10.1016/j.nima.2003.11.299 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900135 ER PT J AU Fixsen, DJ Moseley, SH Cabrera, B Figueroa-Feliciano, E AF Fixsen, DJ Moseley, SH Cabrera, B Figueroa-Feliciano, E TI Pulse estimation in nonlinear detectors with nonstationary noise SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE calorimeter; TES; nonlinear; energy resolution AB We present an algorithm for the least-squares measure of pulse size in the presence of non-stationary system noise through the signal event, which is optimal in both the linear and nonlinear regime. In the case of a linear detector with stationary noise, the algorithm reduces to the Wiener filter. This algorithm is of particular interest with recent advances in the performance of transition edge superconductor (TES) detectors. While these devices can perform near the theoretical limits, their resolution is often limited by the high heat capacities required for linearity at the highest energies. With a robust algorithm for saturated pulse analysis, we can provide significant improvements in resolution while maintaining response over the full energy range. We show the ultimate resolution achievable with TES detectors. (C) 2003 Elsevier B.V. All rights reserved. C1 SSAI, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. LASP, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Stanford Univ, Stanford, CA 94305 USA. RP Fixsen, DJ (reprint author), SSAI, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM fixsen@stars.gsfc.nasa.gov RI Moseley, Harvey/D-5069-2012 NR 4 TC 17 Z9 17 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 555 EP 558 DI 10.1016/j.nima.2003.11.313 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900149 ER PT J AU Tillotson, WA Boyce, KR Brown, GV Cottam, J Figueroa-Feliciano, E Kelley, RL Porter, FS Stahle, CK AF Tillotson, WA Boyce, KR Brown, GV Cottam, J Figueroa-Feliciano, E Kelley, RL Porter, FS Stahle, CK TI Energy scales in X-ray microcalorimeters SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE microcalorimeter array; thermal detectors AB Microcalorimeter pulse shape characteristics, such as pulse height, decay constant, and rise time, are dependent on the detector temperature and bias as well as incident photon energy. We examine the nature of the temperature dependency by illuminating the Astro-E2 X-ray Spectrometer microcalorimeter array with X-rays generated by electron impact on a selection of foil targets. The resulting pulses are collected over a range of detector temperatures. We observe and model these pulses by fitting the data with non-linear pulse models. Our aim is to determine a robust method for correcting the energy scale obtained in ground calibration for slight differences in the operating conditions while in orbit. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, College Pk, MD 20742 USA. RP Tillotson, WA (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM tillotwa@milkyway.gsfc.nasa.gov RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 3 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 595 EP 598 DI 10.1016/j.nima.2003.11.324 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900160 ER PT J AU Shirron, PJ Canavan, ER DiPirro, MJ Jackson, M Tuttle, JG AF Shirron, PJ Canavan, ER DiPirro, MJ Jackson, M Tuttle, JG TI A compact, continuous adiabatic demagnetization refrigerator with high heat sink temperature SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 10th International Workshop on Low Temperature Detectors CY JUL 07-11, 2003 CL Genoa, ITALY DE magnetic refigeration; ADR AB In the continuous adiabatic demagnetization refrigerator (ADR), the existence of a constant temperature stage attached to the load breaks the link between the requirements of the load (usually a detector array) and the operation of the ADR. This allows the ADR to be cycled much faster, which yields more than an order of magnitude improvement in cooling power density over single-shot ADRs. Recent effort has focused on developing compact, efficient higher temperature stages. An important part of this work has been the development of passive gas-gap heat switches that transition (from conductive to insulating) at temperatures around 1 and 4 K without the use of an actively heated getter. We have found that by carefully adjusting available surface area and the number of He-3 monolayers, gas-gap switches can be made to operate passively. Passive operation greatly reduces switching time and eliminates an important parasitic heat load. The current four stage ADR provides 6 muW of cooling at 50 mK (21 muW at 100 mK) and weighs less than 8 kg. It operates from a 4.2 K heat sink, which can be provided by an unpumped He bath or many commercially available mechanical cryocoolers. Reduction in critical current with temperature in our fourth stage NbTi magnet presently limits the maximum temperature of our system to similar to5K. We are developing compact, low-current Nb3Sn magnets that will raise the maximum heat sink temperature to over 10 K. (C) 2003 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Cryogen & Fluids Branch, Greenbelt, MD 20771 USA. RP Canavan, ER (reprint author), NASA, Goddard Space Flight Ctr, Cryogen & Fluids Branch, Greenbelt, MD 20771 USA. EM ecanavan@proxima.gsfc.nasa.gov NR 2 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 11 PY 2004 VL 520 IS 1-3 BP 647 EP 649 DI 10.1016/j.nima.2003.11.367 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 808ZL UT WOS:000220606900175 ER PT J AU Farrah, D Fox, M Rowan-Robinson, M Clements, D Afonso, J AF Farrah, D Fox, M Rowan-Robinson, M Clements, D Afonso, J TI Submillimeter emission from type Ia supernova host galaxies at z=0.5 SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmological parameters; galaxies : high-redshift; supernovae : general ID HUBBLE-DEEP-FIELD; ULTRALUMINOUS INFRARED GALAXIES; STAR-FORMATION HISTORY; HIGH-REDSHIFT; SCUBA-8-MJY SURVEY; LOCAL UNIVERSE; ALPHA SYSTEMS; NUMBER COUNTS; DUST; LUMINOSITY AB We present deep submillimeter observations of 17 galaxies at z = 0.5 that are hosts of a Type Ia supernova. Two galaxies are detected directly, and the sample is detected statistically with a mean 850 mum flux of 1.01 +/- 0.33 mJy, which is 25%-135% higher than locally. We infer that the mean value of A(V) in normal galaxies at z = 0.5 is comparable to or greater than the mean A(V) in local normal galaxies, in agreement with galaxy chemical evolution models and indirect observational evidence. Scaling from the local value given by Rowan-Robinson gives a mean extinction at z = 0.5 of (A(V)) = 0.56 +/- 0.17. The dust in the brightest submillimeter object in our sample is best interpreted as normal "cirrus" dust similar to that seen locally. The detection rate of our sample suggests that some sources found in blank-field submillimeter surveys may not be high-redshift starbursts, but rather cirrus galaxies at moderate redshifts and with lower star formation rates. Finally, an increase in host dust extinction with increasing redshift may impact the cosmological results from distant supernova searches. This emphasizes the need to carefully monitor dust extinction when using Type Ia supernovae to measure the cosmological parameters. C1 CALTECH, Jet Prop Lab, SIRTF Sci Ctr, Pasadena, CA 91125 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Astrophys Grp, London SW7 2BW, England. Observ Astron Lisboa, CAAUL, P-1349018 Lisbon, Portugal. RP Farrah, D (reprint author), CALTECH, Jet Prop Lab, SIRTF Sci Ctr, 4800 Oak Grove Dr, Pasadena, CA 91125 USA. RI Afonso, Jose/B-5185-2013 OI Afonso, Jose/0000-0002-9149-2973 NR 36 TC 12 Z9 12 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 2004 VL 603 IS 2 BP 489 EP 494 DI 10.1086/381487 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LQ UT WOS:000220300600011 ER PT J AU Mitrofanov, IG Anfimov, DS Briggs, MS Fishman, GJ Kippen, RM Kozyrev, AS Litvak, ML Meegan, CA Paciesas, WS Preece, RD Sanin, AB AF Mitrofanov, IG Anfimov, DS Briggs, MS Fishman, GJ Kippen, RM Kozyrev, AS Litvak, ML Meegan, CA Paciesas, WS Preece, RD Sanin, AB TI Analysis methods and results of a search for weak gamma-ray bursts in the batse data SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; methods : statistical ID LOCATIONS; EVOLUTION; RECORDS AB We report initial results on the statistical properties of the dimmest gamma-ray bursts (GRBs) observed with the Burst and Transient Source Experiment (BATSE), using new ground-based methods to obtain a sample of GRBs from 502 days of BATSE data. Using the most sensitive ground-based detection of GRBs, the sample extends to GRBs much fainter than those detected by the onboard trigger, but because of the temporal resolution of the data, the sample is limited to GRBs of duration of at least 2 s. For each detected event, Bayesian probabilities are calculated for the event to belong to each of seven classes of differing physical origins. The sample of GRB candidates is defined by the requirement that the Bayesian probability for belonging to the GRB class is higher than 0.5. The intensity distribution of the GRB sample is corrected using a Monte Carlo simulation of the postflight detection efficiency. The sky distribution of the dimmest BATSE bursts is consistent with isotropy. The dimmest bursts are softer than the brightest triggered bursts. C1 Russian Acad Sci, Space Res Inst, Moscow 117810, Russia. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. Natl Space Sci & Technol Ctr, Huntsville, AL 35805 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mitrofanov, IG (reprint author), Russian Acad Sci, Space Res Inst, 84-32 Profsojuznaya Str, Moscow 117810, Russia. OI Preece, Robert/0000-0003-1626-7335 NR 22 TC 5 Z9 5 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 2004 VL 603 IS 2 BP 624 EP 643 DI 10.1086/380752 PN 1 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LQ UT WOS:000220300600023 ER PT J AU Marshall, FE Gotthelf, EV Middleditch, J Wang, QD Zhang, W AF Marshall, FE Gotthelf, EV Middleditch, J Wang, QD Zhang, W TI The big glitcher: The rotation history of PSR J0537-6910 SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : individual (PSR J0537-6910); stars : neutron; X-rays : stars ID X-RAY PULSAR; SUPERNOVA REMNANT N157B; LARGE-MAGELLANIC-CLOUD; STAR MAGNETIC-FIELD; SPIN-DOWN; CRAB PULSAR; NEUTRON-STARS; BRAKING INDEX; EVOLUTION; B0540-69 AB We report the results of an extensive monitoring campaign of PSR J0537 - 6910, the 16 ms pulsar in the Large Magellanic Cloud, using data acquired with the Rossi X-Ray Timing Explorer. The spin evolution of this pulsar is found to experience extreme episodic discontinuities in its spin-down rate during the 2.6 yr campaign. The rate of occurrence of these timing glitches is 2.3 per year, comparable to the highest seen for any pulsar. The mean glitch amplitude produced a fractional change in the frequency of Deltanu/nu = 0.36 x 10(-6) and in the frequency derivative of Delta(nu) over dot/(nu) over dot = 3 x 10(-4). Despite this prodigious timing activity, we are able to derive a phase-connected timing solution between glitch events with an average spin-down rate of - 1.9743 x 10(-10) Hz s(-1). The integrated effect of the glitches in. (nu) over dot was so large that the apparent characteristic age of the pulsar (-nu/2(nu) over dot) decreased significantly during the campaign. We discuss the implications of a large glitch activity and high braking index on the spin evolution of young pulsars. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. RP Marshall, FE (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. NR 34 TC 24 Z9 24 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 2004 VL 603 IS 2 BP 682 EP 689 DI 10.1086/381567 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LQ UT WOS:000220300600028 ER PT J AU Israel, GL Rea, N Mangano, V Testa, V Perna, R Hummel, W Mignani, R Ageorges, N Lo Curto, G Marco, O Angelini, L Campana, S Covino, S Marconi, G Mereghetti, S Stella, L AF Israel, GL Rea, N Mangano, V Testa, V Perna, R Hummel, W Mignani, R Ageorges, N Lo Curto, G Marco, O Angelini, L Campana, S Covino, S Marconi, G Mereghetti, S Stella, L TI Accurate X-ray position of the anomalous X-ray pulsar XTE J1810-197 and identification of its likely infrared counterpart SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; pulsars : general; pulsars : individual (XTE J1810-197); stars : neutron; X-rays : stars ID MAGNETIZED NEUTRON-STARS; STANDARD STARS; 1E 1048.1-5937; RADIO PULSAR; FIELD; PHOTOMETRY; DISCOVERY; EMISSION; OUTBURST; BURSTS AB We report the accurate subarcsecond X-ray position of the new anomalous X-ray pulsar (AXP) XTE J1810 - 197, derived with a Chandra High Resolution Camera Target of Opportunity observation carried out in 2003 November. We also report the discovery of a likely IR counterpart based on a Very Large Telescope ( IR band) Target of Opportunity observation carried out in 2003 October. Our proposed counterpart is the only IR source (K-s = 20.8) in the X-ray error circle. Its IR colors as well as the X-ray/IR flux ratio are consistent with those of the counterparts of all other AXPs (at variance with field star colors). Deep Gunn i-band images obtained at the 3.6 m ESO telescope detected no sources down to a limiting magnitude of 24.3. Moreover, we find that the pulsed fraction and count rates of XTE J1810 - 197 remained nearly unchanged since the previous Chandra and XMM-Newton observations (2003 August 27 and September 8, respectively). We briefly discuss the implications of these results. In particular, we note that the transient (or at least highly variable) nature of this AXP might imply a relatively large number of hidden members of this class. C1 Osserv Astron Roma, INAF, I-00040 Rome, Italy. Int Ctr Relativist Astrophys, Rome, Italy. Univ Roma Tor Vergata, I-00133 Rome, Italy. Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. European So Observ, D-85748 Garching, Germany. European So Observ, Santiago 19, Chile. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Osserv Astron Brera, INAF, I-23807 Merate, Italy. CNR, IASE, Ist Astrofis Spaziale & Fis Cosm, Sez Milano G Occhialini, I-20133 Milan, Italy. RP Israel, GL (reprint author), Osserv Astron Roma, INAF, Via Frascati 33, I-00040 Rome, Italy. EM gianluca@mporzio.astro.it RI Rea, Nanda/I-2853-2015; OI Rea, Nanda/0000-0003-2177-6388; Campana, Sergio/0000-0001-6278-1576; MEREGHETTI, SANDRO/0000-0003-3259-7801; Israel, GianLuca/0000-0001-5480-6438; Covino, Stefano/0000-0001-9078-5507; Testa, Vincenzo/0000-0003-1033-1340 NR 44 TC 40 Z9 40 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 2004 VL 603 IS 2 BP L97 EP L100 DI 10.1086/382875 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LS UT WOS:000220300800009 ER PT J AU Veronig, AM Brown, JC AF Veronig, AM Brown, JC TI A coronal thick-target interpretation of two hard X-ray loop events SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : flares; Sun : X-rays, gamma rays ID SOLAR-FLARES; RHESSI; MECHANISMS; ELECTRONS; EMISSION AB We report a new class of solar flare hard X-ray (HXR) sources in which the emission is mainly in a coronal loop so dense as to be collisionally thick at electron energies up to greater than or similar to 50 keV. In most of the events previously reported, most of the emission is at the dense loop footpoints, although sometimes with a faint high-altitude component. HXR RHESSI data on loop dimensions and nonthermal electron parameters and GOES soft X-ray data on hot loop plasma parameters are used to model coronal thick-target physics for two "discovery" events (2002 April 14 [23: 56 UT] and 2002 April 15 [23: 05 UT]). We show that loop column densities N are consistent with (1) a nonthermal coronal thick-target interpretation of the HXR image and spectrum; (2) chromospheric evaporation by thermal conduction from the hot loop rather than by electron beam heating; and (3) the hot loop temperature being due to a balance of thick-target collisional heating and (mainly) conductive cooling. C1 Graz Univ, Inst Geophys Astrophys & Meteorol, A-8010 Graz, Austria. Univ Glasgow, Dept Phys & Astron, Astron & Astrophys Grp, Glasgow G12 8QQ, Lanark, Scotland. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Graz Univ, Inst Geophys Astrophys & Meteorol, Univ Pl 5, A-8010 Graz, Austria. RI Veronig, Astrid/B-8422-2009 NR 19 TC 107 Z9 109 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 2004 VL 603 IS 2 BP L117 EP L120 DI 10.1086/383199 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 804LS UT WOS:000220300800014 ER PT J AU Petrov, L Boy, JP AF Petrov, L Boy, JP TI Study of the atmospheric pressure loading signal in very long baseline interferometry observations SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article DE atmospheric pressure loading; VLBI ID SURFACE PRESSURE; ENERGY BALANCES; EARTHS SURFACE; LAND WATER; MODEL; CIRCULATION; GRAVITY AB Redistribution of air masses due to atmospheric circulation causes loading deformation of the Earth's crust, which can be as large as 20 mm for the vertical component and 3 mm for horizontal components. Rigorous computation of site displacements caused by pressure loading requires knowledge of the surface pressure field over the entire Earth surface. A procedure for computing three-dimensional displacements of geodetic sites of interest using a 6 hourly pressure field from the National Centers for Environmental Prediction numerical weather models and the Ponte and Ray [2002] model of atmospheric tides is presented. We investigated possible error sources and found that the errors of our pressure loading time series are below the 15% level. We validated our model by estimating the admittance factors of the pressure loading time series using a data set of 3.5 million very long baseline interferometry observations from 1980 to 2002. The admittance factors averaged over all sites are 0.95 +/- 0.02 for the vertical displacement and 1.00 +/- 0.07 for the horizontal displacements. For the first time, horizontal displacements caused by atmospheric pressure loading have been detected. The closeness of these admittance factors to unity allows us to conclude that on average, our model quantitatively agrees with the observations within the error budget of the model. At the same time we found that the model is not accurate for several stations that are near a coast or in mountain regions. We conclude that our model is suitable for routine data reduction of space geodesy observations. C1 NASA, NVI Inc, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Petrov, L (reprint author), NASA, NVI Inc, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM leonid.petrov@lpetrov.net; jpboy@eost.u-strasbg.fr RI Boy, Jean-Paul/E-6677-2017 OI Boy, Jean-Paul/0000-0003-0259-209X NR 38 TC 123 Z9 126 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAR 10 PY 2004 VL 109 IS B3 AR B03405 DI 10.1029/2003JB002500 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 806KX UT WOS:000220433900001 ER PT J AU Rubinstein, R Clark, TT Livescu, D Luo, LS AF Rubinstein, R Clark, TT Livescu, D Luo, LS TI Time-dependent isotropic turbulence SO JOURNAL OF TURBULENCE LA English DT Article; Proceedings Paper CT 3rd International Symposium on Turbulence and Shear Flow Phenomena CY JUN 24-27, 2003 CL SEBDAL, JAPAN ID TRANSPORT MODEL; EQUATION; CLOSURES; FLOWS AB Homogeneous isotropic turbulence subject to linearly increasing forcing is investigated as a unit problem for statistically unsteady turbulence. The transient spectral dynamics is analysed using a closure theory. A long time asymptotic state is found with k(-7/3) corrections to the energy spectrum as proposed by Yoshizawa. Although the cancellation of O(Re-1/2) terms underlying the standard dissipation rate equation is confirmed in this asymptotic state, it is found that this equation cannot predict the transient dynamics accurately. The discrepancies are explained in terms of the basic mechanisms of vortex stretching and enstrophy destruction responsible for the evolution of the dissipation rate. C1 NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Hampton, VA 23681 USA. Los Alamos Natl Lab, Div X 3 X, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Comp & Computat Sci Div CCS 2, Los Alamos, NM 87545 USA. Natl Inst Aerosp, Hampton, VA 23681 USA. RP Rubinstein, R (reprint author), NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Hampton, VA 23681 USA. EM r.rubinstein@larc.nasa.gov RI Luo, Li-Shi/A-4561-2011 OI Luo, Li-Shi/0000-0003-1215-7892 NR 26 TC 8 Z9 8 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1468-5248 J9 J TURBUL JI J. Turbul. PD MAR 8 PY 2004 VL 5 AR 011 DI 10.1080/1468-5248/5/1/011 PG 16 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 801QZ UT WOS:000220111700001 ER PT J AU Allen, B Woan, G Abbott, B Abbott, R Adhikari, R Allen, B Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Asiri, F Aufmuth, P Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, D Barker-Patton, C Barnes, M Barr, B Barton, MA Bayer, K Beausoleil, R Belczynski, K Bennett, R Berukoff, SJ Betzwieser, J Bhawal, B Billingsley, G Black, E Blackburn, K Bland-Weaver, B Bochner, B Bogue, L Bork, R Bose, S Brady, PR Brau, JE Brown, DA Brozek, S Bullington, A Buonanno, A Burgess, R Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cantley, CA Cardenas, L Carter, K Casey, MM Castiglione, J Chandler, A Chapsky, J Charlton, P Chatterji, S Chen, Y Chickarmane, V Chin, D Christensen, N Churches, D Colacino, C Coldwell, R Creighton, TD Crooks, DRM Csatorday, P Cusack, BJ Cutler, C D'Ambrosio, ED Danzmann, K Davies, R Daw, E DeBra, D Delker, T DeSalvo, R Dhurandar, S Diaz, M Ding, H Drever, RWP Dupuis, RJ Ebeling, C Edlund, J Ehrens, P Elliffe, EJ Etzel, T Evans, M Evans, T Fallnich, C Farnham, D Fejer, MM Fine, M Finn, LS Flanagan, E Freise, A Frey, R Fritschel, P Frolov, V Fyffe, M Ganezer, KS Giaime, JA Gillespie, A Goda, K Gonzalez, G Gobler, S Grandclement, P Grant, A Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, E Gustafson, R Hamilton, WO Hammond, M Hanson, J Hardham, C Harry, G Hartunian, A Heefner, J Hefetz, Y Heinzel, G Heng, IS Hennessy, M Hepler, N Heptonstall, A Heurs, M Hewitson, M Hindman, N Hoang, P Hough, J Hrynevych, M Hua, W Ingley, R Ito, M Itoh, Y Ivanov, A Jennrich, O Johnson, WW Johnston, W Jones, L Jungwirth, D Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Kern, J Khan, A Killbourn, S Killow, CJ Kim, C King, C King, P Klimenko, S Kloevekorn, P Koranda, S Kotter, K Kovalik, J Kozak, D Krishnan, B Landry, M Langdale, J Lantz, B Lawrence, R Lazzarini, A Lei, M Leonhardt, V Leonor, I Libbrecht, M Luck, H Lyons, TT Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Majid, W Malec, M Mann, F Marin, A Marka, S Maros, E Mason, J Mason, K Matherny, O Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNamara, P Mendell, G Meshkov, S Messenger, C Mitselmakher, G Mittleman, R Miyakawa, O Miyoki, S Mohanty, S Moreno, G Mossavi, K Mours, B Mueller, G Mukherjee, S Myers, J Nagano, S Nash, T Naundorf, H Nayak, R Newton, G Nocera, F Nutzman, P Olson, T O'Reilly, B Ottaway, DJ Ottewill, A Ouimette, D Overmier, H Owen, BJ Papa, MA Parameswariah, C Parameswariah, V Pedraza, M Penn, S Pitkin, M Plissi, M Pratt, M Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rao, SR Redding, D Regehr, MW Regimbau, T Reilly, KT Reithmaier, K Reitze, DH Richman, S Riesen, R Riles, K Rizzi, A Robertson, DI Robertson, NA Robison, L Roddy, S Rollins, J Romano, JD Romie, J Rong, H Rose, D Rotthoff, E Rowan, S Rudiger, A Russell, P Ryan, K Salzman, I Sanders, GH Sannibale, V Sathyaprakash, B Saulson, PR Savage, R Sazonov, A Schilling, R Schlaufman, K Schmidt, V Schofield, R Schrempel, M Schutzl, BF Schwinberg, P Scott, SM Searle, AC Sears, B Seel, S Sengupta, AS Shapiro, CA Shawhan, P Shoemaker, DH Shu, QZ Sibley, A Siemens, X Sievers, L Sigg, D Sintes, AM Skeldon, K Smith, JR Smith, M Smith, MR Sneddon, P Spero, R Stapfer, G Strain, KA Strom, D Stuver, A Summerscales, T Sumner, MC Sutton, PJ Sylvestre, J Takamori, A Tanner, DB Tariq, H Taylor, I Taylor, R Throne, KS Tibbits, M Tilav, S Tinto, M Torres, C Torrie, C Traeger, S Traylor, G Tyler, W Ugolini, D Vallisneri, M van Putten, M Vass, S Vecchio, A Vorvick, C Wallace, L Walther, H Ward, H Ware, B Watts, K Webber, D Weidner, A Weiland, U Weinstein, A Weiss, R Welling, H Wen, L Wen, S Whelan, JT Whitcomb, SE Whiting, BF Willems, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, BJ Winkler, W Wise, S Wiseman, AG Woan, G Wooley, R Worden, J Yakushin, I Yamamoto, H Yoshida, S Zawischa, I Zhang, L Zotov, N Zucker, M Zweizig, J AF Allen, B Woan, G Abbott, B Abbott, R Adhikari, R Allen, B Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Asiri, F Aufmuth, P Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, D Barker-Patton, C Barnes, M Barr, B Barton, MA Bayer, K Beausoleil, R Belczynski, K Bennett, R Berukoff, SJ Betzwieser, J Bhawal, B Billingsley, G Black, E Blackburn, K Bland-Weaver, B Bochner, B Bogue, L Bork, R Bose, S Brady, PR Brau, JE Brown, DA Brozek, S Bullington, A Buonanno, A Burgess, R Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cantley, CA Cardenas, L Carter, K Casey, MM Castiglione, J Chandler, A Chapsky, J Charlton, P Chatterji, S Chen, Y Chickarmane, V Chin, D Christensen, N Churches, D Colacino, C Coldwell, R Creighton, TD Crooks, DRM Csatorday, P Cusack, BJ Cutler, C D'Ambrosio, ED Danzmann, K Davies, R Daw, E DeBra, D Delker, T DeSalvo, R Dhurandar, S Diaz, M Ding, H Drever, RWP Dupuis, RJ Ebeling, C Edlund, J Ehrens, P Elliffe, EJ Etzel, T Evans, M Evans, T Fallnich, C Farnham, D Fejer, MM Fine, M Finn, LS Flanagan, E Freise, A Frey, R Fritschel, P Frolov, V Fyffe, M Ganezer, KS Giaime, JA Gillespie, A Goda, K Gonzalez, G Gobler, S Grandclement, P Grant, A Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, E Gustafson, R Hamilton, WO Hammond, M Hanson, J Hardham, C Harry, G Hartunian, A Heefner, J Hefetz, Y Heinzel, G Heng, IS Hennessy, M Hepler, N Heptonstall, A Heurs, M Hewitson, M Hindman, N Hoang, P Hough, J Hrynevych, M Hua, W Ingley, R Ito, M Itoh, Y Ivanov, A Jennrich, O Johnson, WW Johnston, W Jones, L Jungwirth, D Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Kern, J Khan, A Killbourn, S Killow, CJ Kim, C King, C King, P Klimenko, S Kloevekorn, P Koranda, S Kotter, K Kovalik, J Kozak, D Krishnan, B Landry, M Langdale, J Lantz, B Lawrence, R Lazzarini, A Lei, M Leonhardt, V Leonor, I Libbrecht, M Luck, H Lyons, TT Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Majid, W Malec, M Mann, F Marin, A Marka, S Maros, E Mason, J Mason, K Matherny, O Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNamara, P Mendell, G Meshkov, S Messenger, C Mitselmakher, G Mittleman, R Miyakawa, O Miyoki, S Mohanty, S Moreno, G Mossavi, K Mours, B Mueller, G Mukherjee, S Myers, J Nagano, S Nash, T Naundorf, H Nayak, R Newton, G Nocera, F Nutzman, P Olson, T O'Reilly, B Ottaway, DJ Ottewill, A Ouimette, D Overmier, H Owen, BJ Papa, MA Parameswariah, C Parameswariah, V Pedraza, M Penn, S Pitkin, M Plissi, M Pratt, M Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rao, SR Redding, D Regehr, MW Regimbau, T Reilly, KT Reithmaier, K Reitze, DH Richman, S Riesen, R Riles, K Rizzi, A Robertson, DI Robertson, NA Robison, L Roddy, S Rollins, J Romano, JD Romie, J Rong, H Rose, D Rotthoff, E Rowan, S Rudiger, A Russell, P Ryan, K Salzman, I Sanders, GH Sannibale, V Sathyaprakash, B Saulson, PR Savage, R Sazonov, A Schilling, R Schlaufman, K Schmidt, V Schofield, R Schrempel, M Schutzl, BF Schwinberg, P Scott, SM Searle, AC Sears, B Seel, S Sengupta, AS Shapiro, CA Shawhan, P Shoemaker, DH Shu, QZ Sibley, A Siemens, X Sievers, L Sigg, D Sintes, AM Skeldon, K Smith, JR Smith, M Smith, MR Sneddon, P Spero, R Stapfer, G Strain, KA Strom, D Stuver, A Summerscales, T Sumner, MC Sutton, PJ Sylvestre, J Takamori, A Tanner, DB Tariq, H Taylor, I Taylor, R Throne, KS Tibbits, M Tilav, S Tinto, M Torres, C Torrie, C Traeger, S Traylor, G Tyler, W Ugolini, D Vallisneri, M van Putten, M Vass, S Vecchio, A Vorvick, C Wallace, L Walther, H Ward, H Ware, B Watts, K Webber, D Weidner, A Weiland, U Weinstein, A Weiss, R Welling, H Wen, L Wen, S Whelan, JT Whitcomb, SE Whiting, BF Willems, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, BJ Winkler, W Wise, S Wiseman, AG Woan, G Wooley, R Worden, J Yakushin, I Yamamoto, H Yoshida, S Zawischa, I Zhang, L Zotov, N Zucker, M Zweizig, J CA LIGO Sci Collaboration TI Upper limits on the strength of periodic gravitational waves from PSR J1939+2134 SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article; Proceedings Paper CT 5th Edoardo Amaldi Conference on Gravitational Waves CY JUL 06-11, 2003 CL Tirrenia, ITALY AB The first science run of the LIGO and GEO gravitational wave detectors presented the opportunity to test methods of searching for gravitational waves from known pulsars. Here we present new direct upper limits on the strength of waves from the pulsar PSR J1939+2134 using two independent analysis methods, one in the frequency domain using frequentist statistics and one in the time domain using Bayesian inference. Both methods show that the strain amplitude at Earth from this pulsar is less than a few times 10(-22). C1 Albert Einstein Inst Gravitat Phys, D-14476 Golm, Germany. Albert Einstein Inst Gravitat Phys, D-30157 Hannover, Germany. Australian Natl Univ, Canberra, ACT 0200, Australia. CALTECH, Pasadena, CA 91125 USA. Calif State Univ Dominguez Hills, Carson, CA 90747 USA. CALTECH, CaRT, Pasadena, CA 91125 USA. Cardiff Univ, Cardiff CF2 3YB, S Glam, Wales. Carleton Coll, Northfield, MN 55057 USA. Cornell Univ, Ithaca, NY 14853 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Hobart & William Smith Coll, Geneva, NY 14456 USA. Inter Univ Ctr Astron & Astrophys, Pune 411007, Maharashtra, India. CALTECH, LIGO, Pasadena, CA 91125 USA. MIT, LIGO, Cambridge, MA 02139 USA. LIGO Hanford Observ, Richland, WA 99352 USA. LIGO Livingston Observ, Livingston, LA 70754 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Loyola Univ, New Orleans, LA 70118 USA. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Astron Observ, Tokyo 1818588, Japan. Northwestern Univ, Evanston, IL 60208 USA. Salish Kootenai Coll, Pablo, MT 59855 USA. SE Louisiana Univ, Hammond, LA 70402 USA. Stanford Univ, Stanford, CA 94305 USA. Syracuse Univ, Syracuse, NY 13244 USA. Penn State Univ, University Pk, PA 16802 USA. Univ Texas, Brownsville, TX 78520 USA. Texas Southmost Coll, Brownsville, TX 78520 USA. Trinity Univ, San Antonio, TX 78212 USA. Leibniz Univ Hannover, D-30167 Hannover, Germany. Univ Illes Balears, E-07071 Palma de Mallorca, Spain. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Florida, Gainesville, FL 32611 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Rochester, Rochester, NY 14627 USA. Univ Wisconsin, Milwaukee, WI 53201 USA. Washington State Univ, Pullman, WA 99164 USA. RP Albert Einstein Inst Gravitat Phys, D-14476 Golm, Germany. RI Lueck, Harald/F-7100-2011; Freise, Andreas/F-8892-2011; Kawabe, Keita/G-9840-2011; Allen, Bruce/K-2327-2012; Sylvestre, Julien/A-8610-2009; Beausoleil, Raymond/C-5076-2009; McClelland, David/E-6765-2010; Schutz, Bernard/B-1504-2010; Casey, Morag/C-9703-2010; Rowan, Sheila/E-3032-2010; Strain, Kenneth/D-5236-2011; Raab, Frederick/E-2222-2011; Pitkin, Matthew/I-3802-2013; van Putten, Maurice/F-5237-2011; Vecchio, Alberto/F-8310-2015; Finn, Lee Samuel/A-3452-2009; Ottaway, David/J-5908-2015; Ottewill, Adrian/A-1838-2016; Sigg, Daniel/I-4308-2015; Frey, Raymond/E-2830-2016; OI Lueck, Harald/0000-0001-9350-4846; Allen, Bruce/0000-0003-4285-6256; Sylvestre, Julien/0000-0001-8136-4348; McClelland, David/0000-0001-6210-5842; Strain, Kenneth/0000-0002-2066-5355; Pitkin, Matthew/0000-0003-4548-526X; Vecchio, Alberto/0000-0002-6254-1617; Finn, Lee Samuel/0000-0002-3937-0688; Ottewill, Adrian/0000-0003-3293-8450; Sigg, Daniel/0000-0003-4606-6526; Frey, Raymond/0000-0003-0341-2636; Whelan, John/0000-0001-5710-6576; Zweizig, John/0000-0002-1521-3397; Heurs, Michele/0000-0002-5577-2273; Papa, M.Alessandra/0000-0002-1007-5298 NR 5 TC 4 Z9 4 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 EI 1361-6382 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD MAR 7 PY 2004 VL 21 IS 5 SI SI BP S671 EP S676 AR PII S0264-9381(04)69831-5 DI 10.1088/0264-9381/21/5/042 PG 6 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 805CQ UT WOS:000220344800043 ER PT J AU Hyde, TT Maghami, PG Merkowitz, SM AF Hyde, TT Maghami, PG Merkowitz, SM TI Pointing acquisition and performance for the laser interferometry space antenna mission SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article; Proceedings Paper CT 5th Edoardo Amaldi Conference on Gravitational Waves CY JUL 06-11, 2003 CL Tirrenia, ITALY AB The laser interferometer space antenna (LISA) mission, a space-based gravitational wave detector, uses laser metrology to measure distance fluctuations between proof masses aboard three spacecraft. Each spacecraft has two incoming and two outgoing laser beams for a total of six laser links. These links are established sequentially at the start of the mission, and the spacecraft control systems must aim their lasers at each other with pointing motions less than 8 nrad Hz(-1/2) in the frequency band 1-100 mHz. The process for acquiring the laser links as well as the simulated performance is described. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Hyde, TT (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Merkowitz, Stephen/D-6680-2012 OI Merkowitz, Stephen/0000-0002-0412-4209 NR 3 TC 2 Z9 2 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD MAR 7 PY 2004 VL 21 IS 5 SI SI BP S635 EP S640 AR PII S0264-9381(04)68257-8 DI 10.1088/0264-9381/21/5/036 PG 6 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 805CQ UT WOS:000220344800037 ER PT J AU Merkowitz, SM Conkey, S Haile, WB Kelly, WR Peabody, H Dumont, PJ AF Merkowitz, SM Conkey, S Haile, WB Kelly, WR Peabody, H Dumont, PJ TI Structural, thermal, optical and gravitational modelling for LISA SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article; Proceedings Paper CT 5th Edoardo Amaldi Conference on Gravitational Waves CY JUL 06-11, 2003 CL Tirrenia, ITALY AB The laser interferometer space antenna (LISA) mission uses laser interferometry to detect and observe gravitational waves from astrophysical sources. Modelling of LISA ultimately needs to forecast and interrelate the behaviour of the science input, structure, optics, control systems and many other factors that affect the performance of the flight hardware. These models include high precision STOP (structural-thermal-optical) analyses. In addition, self-gravity analyses of the spacecraft, based on the structural-thermal modelling results, are required for each analysis cycle to understand the gravitational interaction between the spacecraft components. The complete analysis cycle is called STOP-G. Several aspects of this analysis require unprecedented precision due to LISA's challenging design requirements. We present here a modelling approach designed to minimize analysis errors, particularly those that enter when mapping results from one modelling step to the next. Central to the approach is the use of a single model topology for all phases of the STOP-G analysis cycle. The feasibility of this approach was verified using a simplified model of the LISA spacecraft. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Swales Aerosp, Beltsville, MD 20705 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Merkowitz, SM (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Merkowitz, Stephen/D-6680-2012 OI Merkowitz, Stephen/0000-0002-0412-4209 NR 3 TC 9 Z9 9 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD MAR 7 PY 2004 VL 21 IS 5 SI SI BP S603 EP S610 AR PII S0264-9381(04)68254-2 DI 10.1088/0264-9381/21/5/032 PG 8 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 805CQ UT WOS:000220344800033 ER PT J AU Mohanty, SD Marka, S Rahkola, R Mukherjee, S Leonor, I Frey, R Cannizzo, J Camp, J AF Mohanty, SD Marka, S Rahkola, R Mukherjee, S Leonor, I Frey, R Cannizzo, J Camp, J TI Gamma ray bursts and gravitational waves: triggered search strategy in the LIGO science runs SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article; Proceedings Paper CT 5th Edoardo Amaldi Conference on Gravitational Waves CY JUL 06-11, 2003 CL Tirrenia, ITALY ID INTERFEROMETRIC DATA; NOISE AB We describe a complete analysis pipeline for detecting and estimating gravitational wave signals in conjunction with observations of astrophysical phenomena with an electromagnetic or particle signature, examples of such phenomena being gamma ray bursts (GRB) and supemovae neutrino bursts. Our data analysis methods explicitly account for non-Gaussian and nonstationary features in real interferometric data. This pipeline is meant for signal searches in conjunction with individual GRB triggers and is being used for the analysis of data from the LIGO science runs (S1 and S2). However, many aspects of the pipeline are quite general and can also be used for other broadband interferometric detectors. C1 Max Planck Inst Gravitat Phys, D-14476 Golm, Germany. CALTECH, LIGO, Pasadena, CA 91125 USA. Univ Oregon, Eugene, OR 97403 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Univ Texas, 80 Ft Brown, Brownsville, TX 78520 USA. RI Frey, Raymond/E-2830-2016 OI Frey, Raymond/0000-0003-0341-2636 NR 31 TC 13 Z9 13 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 EI 1361-6382 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD MAR 7 PY 2004 VL 21 IS 5 SI SI BP S765 EP S774 AR PII S0264-9381(04)68269-4 DI 10.1088/0264-9381/21/5/055 PG 10 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 805CQ UT WOS:000220344800056 ER PT J AU Spero, R Kuhnert, A AF Spero, R Kuhnert, A TI The ST7 interferometer SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article; Proceedings Paper CT 5th Edoardo Amaldi Conference on Gravitational Waves CY JUL 06-11, 2003 CL Tirrenia, ITALY AB Two homodyne Michelson interferometers aboard the LISA Pathfinder spacecraft will measure the positions of two free-floating test masses, as part of the NASA ST7 mission. The interferometer is required to measure the separation between the test masses with a sensitivity of 30 pm Hz(-1/2) at 10 mHz. The readout scheme is described, error sources are analysed and experimental results are presented. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Spero, R (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 4 TC 3 Z9 3 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD MAR 7 PY 2004 VL 21 IS 5 SI SI BP S589 EP S595 AR PII S0264-9381(04)69476-7 DI 10.1088/0264-9381/21/5/030 PG 7 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 805CQ UT WOS:000220344800031 ER PT J AU Stebbins, RT Bender, PL Hanson, J Hoyle, CD Schumaker, BL Vitale, S AF Stebbins, RT Bender, PL Hanson, J Hoyle, CD Schumaker, BL Vitale, S TI Current error estimates for LISA spurious accelerations SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article; Proceedings Paper CT 5th Edoardo Amaldi Conference on Gravitational Waves CY JUL 06-11, 2003 CL Tirrenia, ITALY ID DRAG-FREE CONTROL; TECHNOLOGY AB The performance of the LISA gravitational wave detector depends critically on limiting spurious accelerations of the fiducial masses. Consequently, the requirements on allowable acceleration levels must be carefully allocated based on estimates of the achievable limits on spurious accelerations from all disturbances. Changes in the allocation of requirements are being considered, and are proposed here. The total spurious acceleration error requirement would remain unchanged, but a few new error sources would be added, and the allocations for some specific error sources would be changed. In support of the recommended revisions in the requirements budget, estimates of plausible acceleration levels for 17 of the main error sources are discussed. In most cases, the formula for calculating the size of the effect is known, but there may be questions about the values of various parameters to use in the estimates. Different possible parameter values have been discussed, and a representative set is presented. Improvements in our knowledge of the various experimental parameters will come from planned experimental and modelling studies, supported by further theoretical work. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. Stanford Univ, Stanford, CA 94305 USA. Univ Trent, Trenton, NJ USA. Jet Propuls Lab, Pasadena, CA USA. Univ Trent, Trento, Italy. RP Stebbins, RT (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Stebbins, Robin/G-5009-2013; Vitale, Stefano/C-2312-2012; OI Vitale, Stefano/0000-0002-2427-8918; Hoyle, Charles/0000-0002-2467-6131 NR 11 TC 31 Z9 32 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD MAR 7 PY 2004 VL 21 IS 5 SI SI BP S653 EP S660 AR PII S0264-9381(04)69007-1 DI 10.1088/0264-9381/21/5/039 PG 8 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 805CQ UT WOS:000220344800040 ER PT J AU McKinney, KA Wennberg, PO Dhaniyala, S Fahey, DW Northway, MJ Kunzi, KF Kleinbohl, A Sinnhuber, M Kullmann, H Bremer, H Mahoney, MJ Bui, TP AF McKinney, KA Wennberg, PO Dhaniyala, S Fahey, DW Northway, MJ Kunzi, KF Kleinbohl, A Sinnhuber, M Kullmann, H Bremer, H Mahoney, MJ Bui, TP TI Trajectory studies of large HNO3-containing PSC particles in the Arctic: Evidence for the role of NAT SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID NITRIC-ACID; POLAR STRATOSPHERES; DENITRIFICATION; VORTEX; HNO3 AB Large ( 5 to > 20 mum diameter) nitric-acid-containing polar stratospheric cloud ( PSC) particles were observed in the Arctic stratosphere during the winter of 1999 - 2000. We use a particle growth and sedimentation model to investigate the environment in which these particles grew and the likely phase of the largest particles. Particle trajectory calculations show that, while simulated nitric acid dihydrate (NAD) particle sizes are significantly smaller than the observed maximum particle sizes, nitric acid trihydrate (NAT) particle trajectories are consistent with the largest observed particle sizes. C1 CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. NOAA, Aeron Lab, Boulder, CO 80303 USA. Univ Bremen, Inst Environm Phys, Bremen, Germany. CALTECH, Jet Prop Lab, Pasadena, CA USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Amherst Coll, Dept Chem, Amherst, MA 01002 USA. RI Wennberg, Paul/A-5460-2012; Sinnhuber, Miriam/A-7252-2013; Fahey, David/G-4499-2013 OI Fahey, David/0000-0003-1720-0634 NR 20 TC 4 Z9 4 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 6 PY 2004 VL 31 IS 5 AR L05110 DI 10.1029/2003GL018430 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 803HY UT WOS:000220223400001 ER PT J AU Shindell, DT Schmidt, GA Mann, ME Faluvegi, G AF Shindell, DT Schmidt, GA Mann, ME Faluvegi, G TI Dynamic winter climate response to large tropical volcanic eruptions since 1600 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE climate; volcano; Arctic Oscillation ID NORTHERN-HEMISPHERE WINTER; SURFACE AIR-TEMPERATURE; EL-NINO; PINATUBO ERUPTION; MOUNT-PINATUBO; MODEL SIMULATION; GREENHOUSE-GAS; CIRCULATION; OSCILLATION; SIGNAL AB [1] We have analyzed the mean climate response pattern following large tropical volcanic eruptions back to the beginning of the 17th century using a combination of proxy-based reconstructions and modern instrumental records of cold- season surface air temperature. Warm anomalies occur throughout northern Eurasia, while cool anomalies cover northern Africa and the Middle East, extending all the way to China. In North America, the northern portion of the continent cools, with the anomalies extending out over the Labrador Sea and southern Greenland. The analyses confirm that for two years following eruptions the anomalies strongly resemble the Arctic Oscillation/ Northern Annular Mode (AO/NAM) or the North Atlantic Oscillation (NAO) in the Atlantic-Eurasian sector. With our four-century record, the mean response is statistically significant at the 95% confidence level over much of the Northern Hemisphere land area. However, the standard deviation of the response is larger than the mean signal nearly everywhere, indicating that the anomaly following a single eruption is unlikely to be representative of the mean. Both the mean response and the variability can be successfully reproduced in general circulation model simulations. Driven by the solar heating induced by the stratospheric aerosols, these models produce enhanced westerlies from the lower stratosphere down to the surface. The climate response to volcanic eruptions thus strongly suggests that stratospheric temperature and wind anomalies can affect surface climate by forcing a shift in the AO/NAM or NAO. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Univ Virginia, Dept Environm Sci, Charlottesville, VA 22903 USA. Columbia Univ, Ctr Climate Syst Res, New York, NY 10027 USA. RP NASA, Goddard Inst Space Studies, New York, NY 10025 USA. EM dshindell@giss.nasa.gov RI Shindell, Drew/D-4636-2012; Schmidt, Gavin/D-4427-2012; Mann, Michael/B-8472-2017 OI Schmidt, Gavin/0000-0002-2258-0486; Mann, Michael/0000-0003-3067-296X NR 52 TC 94 Z9 94 U1 4 U2 27 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 6 PY 2004 VL 109 IS D5 AR D05104 DI 10.1029/2003JD004151 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 803IR UT WOS:000220225300002 ER PT J AU Farrell, WM Smith, PH Delory, GT Hillard, GB Marshall, JR Catling, D Hecht, M Tratt, DM Renno, N Desch, MD Cummer, SA Houser, JG Johnson, B AF Farrell, WM Smith, PH Delory, GT Hillard, GB Marshall, JR Catling, D Hecht, M Tratt, DM Renno, N Desch, MD Cummer, SA Houser, JG Johnson, B TI Electric and magnetic signatures of dust devils from the 2000-2001 MATADOR desert tests SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article DE triboelectricity; electric fields; dust devils; magnetic fields; atmospheric electricity ID MARS PATHFINDER; STORMS; DISCHARGES; GENERATION; ATMOSPHERE; VORTICES; MODEL; FIELD AB [1] Dust devils are significant meteorological phenomena on Mars: They are ubiquitous, continually gardening the Martian surface, and may be the primary atmospheric dust-loading mechanism in nonstorm seasons. Further, dust grains in the swirling dust devils may become electrically charged via triboelectric effects. Electrical effects associated with terrestrial dust devils have been reported previously, but these were isolated measurements ( electric fields only) with no corroborating measurements. To study the fluid and electrical forces associated with dust devils, NASA's Human Exploration and Development of Space (HEDS) enterprise sponsored a set of desert field tests with a suite of mutually compatible and complementary instruments in order to determine the relationship between electric, magnetic, and fluid forces. The project ( originally a selected flight project) was entitled "Martian ATmosphere And Dust in the Optical and Radio'' ( MATADOR). In this work, we present a number of interesting examples of the electromagnetic nature of the dust devil. We also describe potential hazards of the dust devil and how similar devil- and storm-related forces on Mars might affect any human occupation. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. SETI Inst, Mountain View, CA 94043 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NASA, Earth Sci Technol Off, Greenbelt, MD USA. Univ Michigan, Ann Arbor, MI 48109 USA. Duke Univ, Dept Elect & Comp Engn, Durham, NC 27706 USA. RP Farrell, WM (reprint author), NASA, Goddard Space Flight Ctr, Mail Code 695, Greenbelt, MD 20771 USA. EM william.farrell@gsfc.nasa.gov RI Cummer, Steven/A-6118-2008; Tratt, David/A-7884-2009; Catling, David/D-2082-2009; Farrell, William/I-4865-2013 OI Cummer, Steven/0000-0002-0002-0613; Tratt, David/0000-0002-3942-6848; NR 31 TC 78 Z9 80 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAR 5 PY 2004 VL 109 IS E3 AR E03004 DI 10.1029/2003JE002088 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 803JB UT WOS:000220226300002 ER PT J AU Burkepile, JT Hundhausen, AJ Stanger, AL St Cyr, OC Seiden, JA AF Burkepile, JT Hundhausen, AJ Stanger, AL St Cyr, OC Seiden, JA TI Role of projection effects on solar coronal mass ejection properties: 1. A study of CMEs associated with limb activity SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE coronal mass ejections; corona ID 2 DYNAMICAL TYPES; X-RAY EVENTS; SMM OBSERVATIONS; TRANSIENT; FLARES; SKYLAB; ORIGIN; SPEEDS AB [1] Many properties of Coronal Mass Ejections (CMEs), such as size, location and brightness, have been determined from measurements of white light coronal observations. We expect the average properties derived from these measurements contain systematic inaccuracies due to projection effects and suggest that CME properties are most accurately determined for those events occurring near the plane-of-the-sky (i.e., over the solar limb as observed from Earth), where projection effects are minimized. A set of 111 such "limb'' events have been identified in Solar Maximum Mission (SMM) white light observations through associations with Erupting Prominences at the Limb (EPLs), and X-ray and limb optical flares. These "limb'' CMEs have greater average speeds ( 519 +/- 46 km/sec) and masses (4.5 +/- .5 x 10(15) grams) than the average values obtained from all SMM CMEs, consistent with the expected behavior of projection effects. Only a very small percentage of "limb'' CMEs are centered at high latitudes, suggesting there are many fewer "true'' high latitude CMEs than has previously been reported. No "limb'' CMEs have widths greater than 110degrees, consistent with the interpretation that very wide CMEs (i.e., halos) are actually events of more typical widths originating away from the solar limb and viewed in projection. Only a small percentage of "limb'' CMEs have measured speeds below 200 km/sec, indicating there may be fewer "true'' subsonic SMM CMEs than previously reported. The correlation detected between the kinetic energy of the "limb'' CMEs and the peak intensity of the associated GOES X-ray flares, is stronger than was previously found using a set of CMEs of undetermined limb distances. All these results provide strong evidence that projection effects systematically influence the deduced properties of CME events. C1 Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Natl Ctr Atmospher Res, High Altitude Observ, POB 3000, Boulder, CO 80307 USA. EM iguana@hao.ucar.edu NR 49 TC 86 Z9 86 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 5 PY 2004 VL 109 IS A3 AR A03103 DI 10.1029/2003JA010149 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 803JP UT WOS:000220227700002 ER PT J AU Green, JL Boardsen, S Fung, SF Matsumoto, H Hashimoto, K Anderson, RR Sandel, BR Reinisch, BW AF Green, JL Boardsen, S Fung, SF Matsumoto, H Hashimoto, K Anderson, RR Sandel, BR Reinisch, BW TI Association of kilometric continuum radiation with plasmaspheric structures SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE kilometric continuum; plasma waves; plasmasphere; plasmapause ID NONTHERMAL CONTINUUM; FREQUENCY; GEOTAIL; MAGNETOSPHERE; PLASMAPAUSE; TERRESTRIAL; SPACECRAFT; EMISSION; IMAGER; WAVES AB [1] A year's worth of observations of kilometric continuum ( KC) from the plasma wave instrument (PWI) on GEOTAIL and extreme ultraviolet (EUV) images of the plasmasphere from IMAGE are compared. In the vast majority ( similar to 94%) of the 87 cases when simultaneous data from both spacecraft were available, KC was observed to be associated with density depletions or notch structures in the plasmasphere. From a careful analysis of 1 month of EUV data comprising 13 notch structures, only one notch structure was found in which no accompanying KC was observed when GEOTAIL was in a low-latitude position and therefore should have observed the emission if it were generated. IMAGE observations from the radio plasma imager (RPI) during passage through a plasmaspheric notch structure found that KC was generated in or very near the magnetic equator at steep gradients in density and associated with emissions in the upper hybrid resonance band as previously reported by others at lower frequencies. Statistical analysis of the KC events associated with plasmaspheric notch structures shows that the typical source region is at an equatorial radial distance of similar to 2.4 R-E (Earth radii) in the magnetic equator and produces an emission cone that is similar to40degrees in longitude and similar to20degrees in latitude. These results show that a density depletion or notch structure in the plasmasphere is typically a critical condition for the generation of KC but that the notch structures do not always provide the conditions necessary for the generation of the emission. C1 NASA, Commun Analyt Div L3, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Kyoto Univ, Radio Sci Ctr Space & Atmosphere, Kyoto, Japan. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Univ Massachusetts, Ctr Atmospher Res, Lowell, MA 01854 USA. RP Green, JL (reprint author), NASA, Commun Analyt Div L3, Goddard Space Flight Ctr, Code 630, Greenbelt, MD 20771 USA. EM james.green@nasa.gov; boardsen@mail630.gsfc.nasa.gov; shing.f.fung@nasa.gov; matsumot@kurasc.kyoto-u.ac.jp; rra@space.physics.uiowa.edu; sandel@arizona.edu; bodo_reinisch@uml.edu RI Fung, Shing/F-5647-2012 NR 21 TC 21 Z9 21 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 5 PY 2004 VL 109 IS A3 AR A03203 DI 10.1029/2003JA010093 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 803JP UT WOS:000220227700001 ER PT J AU Haberle, RM Mattingly, B Titus, TN AF Haberle, RM Mattingly, B Titus, TN TI Reconciling different observations of the CO2 ice mass loading of the Martian north polar cap SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GENERAL-CIRCULATION MODEL; MARS; SIMULATIONS; CLOUDS AB The GRS measurements of the peak mass loading of the north polar CO2 ice cap on Mars are about 60% lower than those calculated from MGS TES radiation data and those inferred from the MOLA cap thicknesses. However, the GRS data provide the most accurate measurement of the mass loading. We show that the TES and MOLA data can be reconciled with the GRS data if ( 1) subsurface heat conduction and atmospheric heat transport are included in the TES mass budget calculations, and ( 2) the density of the polar deposits is similar to600 kg m(-3). The latter is much less than that expected for slab ice (similar to 1600 kg m(-3)) and suggests that processes unique to the north polar region are responsible for the low cap density. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. San Jose State Univ, Dept Meteorol, San Jose, CA 95192 USA. US Geol Survey, Branch Astrogeol, Flagstaff, AZ 86001 USA. RP Haberle, RM (reprint author), NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. EM robert.m.haberle@nasa.gov NR 23 TC 15 Z9 15 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 4 PY 2004 VL 31 IS 5 AR L05702 DI 10.1029/2004GL019445 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 803HV UT WOS:000220223100007 ER PT J AU Nguyen, CV So, C Stevens, R Li, Y Delziet, L Sarrazin, P Meyyappan, M AF Nguyen, CV So, C Stevens, R Li, Y Delziet, L Sarrazin, P Meyyappan, M TI High lateral resolution imaging with sharpened tip of multi-walled carbon nanotube scanning probe SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID FORCE MICROSCOPY; ELECTRICAL BREAKDOWN AB We report a tip sharpening process for multiwalled carbon nanotube (MWCNT) scanning probes and demonstrate its application in high lateral resolution imaging. The sharpening of the tip is an in-situ process employing the atomic force microscope. The method involves current-induced oxidation in ambient atmosphere by locally stripping away the outer layers at the very tip of the MWCNT. This process requires an applied voltage in the 2-3 V range, which is lower than that required for shortening the nanotube. Direct scanning microscopic data reveal sharpened tips with a radius of curvature normally less than 5 urn. Multiple scan experiments show that the sharpened tips undergo no degradation in image quality, suggesting that the sharpened tips are very robust. Our unique fabrication process for producing a robust multiwalled CNT scanning probe coupled with the tip sharpening method has demonstrated the development of a universal probe for high aspect ratio as well as high lateral resolution imaging applications. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Nguyen, CV (reprint author), ELORET Corp, Sunnyvale, CA 94087 USA. EM cvnguyen@mail.arc.nasa.gov OI So, Christopher/0000-0001-7572-778X NR 18 TC 35 Z9 35 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAR 4 PY 2004 VL 108 IS 9 BP 2816 EP 2821 DI 10.1021/jp0361529 PG 6 WC Chemistry, Physical SC Chemistry GA 800II UT WOS:000220021600010 ER PT J AU Delgado, RM Poulin, GV Vrtovec, B Eastwood, C Radovancevic, B Franklin, W Kar, B Schlegel, TT AF Delgado, RM Poulin, GV Vrtovec, B Eastwood, C Radovancevic, B Franklin, W Kar, B Schlegel, TT TI The utility of high frequency QRS electrocardiogram in the diagnosis of cardiomyopathy SO JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY LA English DT Meeting Abstract CT 54th Annual Scientific Session of the American-College-of-Cardiology CY MAR 07-10, 2004 CL New Orleans, LA SP Amer Coll Cardiol C1 St Lukes Episcopal Hosp, Texas Heart Inst, Houston, TX USA. NASA, Houston, TX USA. NR 0 TC 1 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0735-1097 J9 J AM COLL CARDIOL JI J. Am. Coll. Cardiol. PD MAR 3 PY 2004 VL 43 IS 5 SU A BP 208A EP 209A DI 10.1016/S0735-1097(04)90887-X PG 2 WC Cardiac & Cardiovascular Systems SC Cardiovascular System & Cardiology GA 780NW UT WOS:000189388500889 ER PT J AU Suess, ST Bemporad, A Poletto, G AF Suess, ST Bemporad, A Poletto, G TI A slow streamer blowout at the Sun and Ulysses SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PLANAR MAGNETIC-STRUCTURES; CORONAL MASS EJECTIONS; SOLAR-WIND; COMPLEX; CMES AB On 10 June 2000 a streamer on the southeast limb slowly disappeared from LASCO/C2 over similar to 10 hours. A small CME was reported in C2. A substantial interplanetary CME (ICME) was later detected at Ulysses, which was at quadrature with the Sun and SOHO at the time. This detection illustrates the properties of an ICME for a known solar source and demonstrates that the identification can be done even beyond 3 AU. Slow streamer blowouts such as this have long been known but are little studied. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. Osserv Astrofis Arcetri, INAF, I-50125 Florence, Italy. RP Suess, ST (reprint author), NASA, George C Marshall Space Flight Ctr, Mail Stop SD50, Huntsville, AL 35812 USA. EM steven.t.suess@nasa.gov; bempy76@arcetri.astro.it; poletto@arcetri.astro.it OI Bemporad, Alessandro/0000-0001-5796-5653 NR 16 TC 3 Z9 3 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 2 PY 2004 VL 31 IS 5 AR L05801 DI 10.1029/2003GL018895 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 803HT UT WOS:000220222900004 ER PT J AU Egbert, GD Ray, RD Bills, BG AF Egbert, GD Ray, RD Bills, BG TI Numerical modeling of the global semidiurnal tide in the present day and in the last glacial maximum SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article DE tides; energy dissipation; Last Glacial Maximum ID BAROTROPIC OCEAN TIDES; WORLD OCEAN; HYDRODYNAMIC MODEL; MIXING PROCESSES; ALTIMETER DATA; ENERGY FLUX; DEEP-OCEAN; DISSIPATION; COMPUTATIONS; TOPOGRAPHY AB [1] A hydrodynamic model incorporating a self-consistent treatment of ocean self-attraction and loading ( SAL), and a physically based parameterization of internal tide ( IT) drag, is used to assess how accurately barotropic tides can be modeled without benefit of data, and to explore tidal energetics in the last glacial maximum (LGM). M-2 solutions computed at high resolution with present day bathymetry agree with estimates of elevations from satellite altimetry within 5 cm RMS in the open ocean. This accuracy, and agreement with atlimetric estimates of energy dissipation, are achieved only when SAL and IT drag are included in the model. Solutions are sensitive to perturbations to bathymetry, and inaccuracies in available global databases probably account for much of the remaining error in modeled elevations. The approximate to100 m drop in sea level during the LGM results in significant changes in modeled M2 tides, with some amplitudes in the North Atlantic increasing by factors of 2 or more. Dissipation is also significantly changed by the drop in sea level. If IT drag estimated for the modern ocean is assumed, dissipation increases by about 50% globally, and almost triples in the deep ocean. However, IT drag depends on ocean stratification, which is poorly known for the LGM. Tests with modified IT drag suggest that the tendency to a global increase in dissipation is a robust result, but details are sensitive to stratification. Significant uncertainties about paleotides thus remain even in this comparatively simple case where bathymetry is well constrained. C1 Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Calif San Diego, Scripps Inst Oceanog, Inst Geophys & Planetary Phys, La Jolla, CA 92093 USA. RP Egbert, GD (reprint author), Oregon State Univ, Coll Ocean & Atmospher Sci, Ocean Adm Bldg 104, Corvallis, OR 97331 USA. EM egbert@oce.orst.edu; richard.ray@gsfc.nasa.gov; bruce.g.bills@nasa.gov RI Bills, Bruce/C-1156-2008; Ray, Richard/D-1034-2012 NR 46 TC 127 Z9 129 U1 0 U2 16 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 EI 2169-9291 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAR 2 PY 2004 VL 109 IS C3 AR C03003 DI 10.1029/2003JC001973 PG 15 WC Oceanography SC Oceanography GA 803IT UT WOS:000220225500003 ER PT J AU Hoogenboom, T Smrekar, SE Anderson, FS Houseman, G AF Hoogenboom, T Smrekar, SE Anderson, FS Houseman, G TI Admittance survey of type 1 coronae on Venus SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article DE Venus; corona; gravity; admittance ID EFFECTIVE ELASTIC THICKNESS; OF-SIGHT ACCELERATIONS; MANTLE DYNAMICS; CONTINENTAL LITHOSPHERE; ISOSTATIC COMPENSATION; FLEXURAL RIGIDITY; SURFACE-FEATURES; ORDER MODEL; GRAVITY; TOPOGRAPHY AB [1] In this study, we analyze Magellan gravity and topography data for Type 1 coronae on Venus to estimate crustal thickness (Z(c)), elastic thickness (T-e), and apparent depth of compensation (Z(L)). We examine the free-air admittance for all 103 Type 1 coronae ( defined as having greater than 50% complete fracture annuli) that are resolved in the gravity data. A spatio-spectral method is used to calculate a localized admittance signature of each corona from a global admittance map. This method extracts spectral information from a region in space whose area is varied as a function of degree to make it large enough to yield robust results at every individual wavelength. Elastic flexure models with either bottom- or top-loading compensation are used to fit the data. The estimated lithospheric flexural parameters span the range obtained for other topographic features on Venus, suggesting that the lithosphere on which coronae form is variable. We find no significant difference in lithospheric properties between Type 1 and 2 coronae. Fifty-four percent of all coronae are consistent with local isostasy, which may indicate that they are no longer active. Very few coronae with dome or plateau morphologies have a bottom-loading signature or the small T-e and large Z(L) expected if a mantle plume were present. Approximately 71% have Z(L) estimates less than 70 km, indicating that compensation probably occurs within the crustal layer. We find no systematic relationship between T-e or Z(c) and corona diameter, as would be expected for the spreading-drop model of formation. C1 Univ Leeds, Sch Earth Sci, Leeds LS2 9JT, W Yorkshire, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Hawaii Manoa, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. RP Hoogenboom, T (reprint author), Univ Leeds, Sch Earth Sci, Woodhouse Lane, Leeds LS2 9JT, W Yorkshire, England. EM trudi@earth.leeds.ac.uk NR 54 TC 19 Z9 19 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAR 2 PY 2004 VL 109 IS E3 AR E03002 DI 10.1029/2003JE002171 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 803JA UT WOS:000220226200002 ER PT J AU Plaut, JJ Anderson, SW Crown, DA Stofan, ER van Zyl, JJ AF Plaut, JJ Anderson, SW Crown, DA Stofan, ER van Zyl, JJ TI The unique radar properties of silicic lava domes SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article DE radar; remote sensing; volcanology ID LONG-VALLEY CALDERA; STEEP-SIDED DOMES; INYO VOLCANIC CHAIN; GREENLAND ICE-SHEET; EASTERN CALIFORNIA; OBSIDIAN DOME; MAGELLAN DATA; VENUS; EMPLACEMENT; FLOW AB [1] Silicic lava domes exhibit distinct morphologic characteristics at scales of centimeters to kilometers. Multiparameter radar observations capture the unique geometric signatures of silicic domes in a set of radar scattering properties that are unlike any other natural geologic surfaces. Backscatter cross-section values are among the highest observed on terrestrial lava flows and show only a weak decrease with incidence angle. Cross-polarization backscatter (HV) shows a unique behavior, increasing with increasing wavelength. Circular polarization ratios are relatively high, in the 0.3 - 0.95 range, and increase with increasing wavelength. Field measurements of boulder size frequency distributions and microtopography indicate that silicic dome surfaces are among the roughest ever measured. Rms heights at a 1 m lateral scale range from 13 cm to 50 cm. Rms slopes at 1 m spacing range from 12 to 43 degrees. Modeling of the scattering behavior suggests it results from a combination of rough surface ( facet) scattering and scattering from block edges that act as a random collection of dipoles. The unusual wavelength dependence of the radar parameters appears to result from a higher component of edge scattering at large wavelengths, producing, for example, higher cross-polarized backscatter at P band ( 68 cm). Steep-sided volcanic domes on Venus superficially resemble terrestrial silicic domes in plan view gross morphology, but few similarities remain when the radar scattering and three-dimensional shapes of the features are compared. The unique radar scattering properties suggest that such volcanic surfaces can be identified with multiparameter radar observations in future planetary radar missions and in active terrestrial volcanoes, where dome development can represent serious hazards. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Black Hills State Univ, Dept Sci, Spearfish, SD 57799 USA. Planetary Sci Inst, Tucson, AZ 85719 USA. Proxemy Res, Rectortown, VA 20140 USA. RP Plaut, JJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM plaut@jpl.nasa.gov NR 57 TC 17 Z9 17 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAR 2 PY 2004 VL 109 IS E3 AR E03001 DI 10.1029/2002JE002017 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 803JA UT WOS:000220226200001 ER PT J AU Jits, RY Walberg, GD AF Jits, RY Walberg, GD TI Blended control, predictor-corrector guidance algorithm: an enabling technology for Mars aerocapture SO ACTA ASTRONAUTICA LA English DT Article AB A guidance scheme designed for coping with significant dispersion in the vehicle's state and atmospheric conditions is presented. In order to expand the flyable aerocapture envelope, control of the vehicle is realized through bank angle and angle-of-attack modulation. Thus, blended control of the vehicle is achieved, where the lateral and vertical motions of the vehicle are decoupled. The overall implementation approach is described, together with the guidance algorithm macrologic and structure. Results of guidance algorithm tests in the presence of various single and multiple off-nominal conditions are presented and discussed. (C) 2003 Published by Elsevier Ltd. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Walberg Aerosp, Hampton, VA 23965 USA. RP Jits, RY (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 13 TC 9 Z9 9 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD MAR PY 2004 VL 54 IS 6 BP 385 EP 398 DI 10.1016/S0094-5765(03)00159-0 PG 14 WC Engineering, Aerospace SC Engineering GA 776DR UT WOS:000189101900001 PM 14740659 ER PT J AU Fragomeni, JM Nunes, AC AF Fragomeni, JM Nunes, AC TI Dynamics of space welding impact and corresponding safety welding study SO ACTA ASTRONAUTICA LA English DT Article AB This study was undertaken in order to be sure that no hazard would exist from impingement of hot molten metal particle detachments upon an astronauts space suit during any future electron beam welding exercises or experiments. The conditions under which molten metal detachments might occur in a space welding environment were analyzed. The safety issue is important during welding with regards to potential molten metal detachments from the weld pool and cold filler wire during electron beam welding in space. Theoretical models were developed to predict the possibility and size of the molten metal detachment hazards during the electron beam welding exercises at low earth orbit. Some possible ways of obtaining molten metal drop detachments would include an impulse force, or bump, to the weld sample, cut surface, or filler wire. Theoretical models were determined for these detachment concerns from principles of impact and kinetic energies, surface tension, drop geometry, surface energies, and particle dynamics. A weld pool detachment parameter for specifying the conditions for metal weld pool detachment by impact was derived and correlated to the experimental results. The experimental results were for the most part consistent with the theoretical analysis and predictions. (C) 2003 Elsevier Ltd. All rights reserved. C1 Univ Detroit, Coll Engn & Sci, Dept Mech Engn, Detroit, MI 48219 USA. NASA, George C Marshall Space Flight Ctr, Mat Prod & Mfg Dept, Huntsville, AL 35812 USA. RP Fragomeni, JM (reprint author), Univ Detroit, Coll Engn & Sci, Dept Mech Engn, 4001 W McNichols Rd,POB 19900, Detroit, MI 48219 USA. EM jamesfrag@yahoo.com NR 8 TC 0 Z9 0 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD MAR PY 2004 VL 54 IS 6 BP 399 EP 412 DI 10.1016/S0094-5765(03)00160-7 PG 14 WC Engineering, Aerospace SC Engineering GA 776DR UT WOS:000189101900002 PM 14740660 ER PT J AU Hebert, TJ Africano, J Stansbery, G AF Hebert, TJ Africano, J Stansbery, G TI Automated detection of orbital debris in digital video data from a telescope SO ACTA ASTRONAUTICA LA English DT Article ID IMAGE-RECONSTRUCTION; MODEL; PROOF AB As part of a program to measure, monitor, and predict the orbital debris environment the Orbital Debris Program Office of the NASA Johnson Space Center (JSC) collects video data through a 3-m zenith-staring liquid mirror telescope located in New Mexico. This paper presents methods and results from a PC-based digital video processing system that automates the detection and measurement of orbital debris and meteors in these videotapes. Results using the automated system were compared to those from two trained observers in reviewing 40 h of video. These results demonstrate that the computer-automated system outperforms the combined results from two trained observers, achieving a 17 percent improvement in the detection rate of orbital debris per tape and a three-fold improvement in the detection rate of meteors. Published by Elsevier Ltd. C1 Univ Houston, Dept Elect & Comp Engn, Houston, TX 77204 USA. Boeing N Amer, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Hebert, TJ (reprint author), Univ Houston, Dept Elect & Comp Engn, Houston, TX 77204 USA. EM thebert@uh.edu NR 9 TC 1 Z9 3 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD MAR PY 2004 VL 54 IS 6 BP 455 EP 461 DI 10.1016/S0094-5765(03)00171-1 PG 7 WC Engineering, Aerospace SC Engineering GA 776DR UT WOS:000189101900005 ER PT J AU Bellamy, HD Snell, EH Lovelace, J Pokross, M Borgstahl, GEO AF Bellamy, HD Snell, EH Lovelace, J Pokross, M Borgstahl, GEO TI The high-mosaicity illusion: revealing the true physical characteristics of macromolecular crystals (vol D56, pg 986, 2000) SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Correction C1 Univ Toledo, Dept Chem, Toledo, OH 43606 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NASA, Struct Biol Lab, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Borgstahl, GEO (reprint author), Univ Toledo, Dept Chem, 2801 W Bancroft St, Toledo, OH 43606 USA. EM gborgstahl@unmc.edu NR 3 TC 0 Z9 0 U1 0 U2 1 PU BLACKWELL MUNKSGAARD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD MAR PY 2004 VL 60 BP 619 EP 619 DI 10.1107/S0907444904002604 PN 3 PG 1 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 778CQ UT WOS:000189221900052 ER PT J AU Gandhi, F Sekula, MK AF Gandhi, F Sekula, MK TI Helicopter vibration reduction using fixed-system auxiliary moments SO AIAA JOURNAL LA English DT Article AB Reductions in helicopter rotor hub vibratory loads that can be obtained through the introduction of steady auxiliary pitching and rolling moments in the fixed system are examined. The auxiliary moments allow changes in vehicle attitude and rotor pitch control inputs, such that vibrations can be minimized, while vehicle equilibrium is still satisfied. Because auxiliary moments can be generated by variation of the pitch of the right and left halves of the horizontal tail, the weight penalty, complexity, and performance losses associated with auxiliary lift and thrust (conventional compounding) would be alleviated. A comprehensive rotorcraft aeroelastic analysis was modified to include the fixed system auxiliary moments in the trim equations, and vibration reductions were examined for two different cases: 1) a light BO-105 type helicopter with a four-bladed hingeless rotor at high flight speeds (advance ratio of 0.35) and 2) a medium-weight UH-60 type helicopter with a four-bladed articulated rotor at a more moderate flight speed (advance ratio of 0.25). For the BO-105 type aircraft, a nosedown auxiliary pitching moment and a roll-left auxiliary rolling moment could reduce the in-plane vibratory hub forces by 20-30% when used individually and by 90% when used in combination. For the UH-60 type aircraft, a nosedown auxiliary pitching moment and a roll-right auxiliary rolling moment produced reductions in the range of 15-65% in all components of vibratory hub loads. For both aircraft, the nosedown auxiliary pitching moment increased the nosedown pitch attitude of the aircraft and reduced the rotor longitudinal cyclic flapping and the longitudinal cyclic pitch input. For the BO-105, the roll-left auxiliary moment increased the leftward shaft tilt and no longer required the tip path plane to tilt left relative to the hub plane. This decreased the lateral cyclic pitch input. However, for the UH-60, the roll-right auxiliary moment actually reversed the roll attitude of the aircraft (shaft now tilting right). This required a large leftward tilt of the tip path plane relative to the hub plane and increased the lateral cyclic pitch requirement. When implementation of the auxiliary moments through collective and differential pitch inputs to the horizontal tail was examined, it was observed that the expected reductions in vibration were indeed achieved, but that the auxiliary roll moment generated was smaller than expected due to one-half of the horizontal tail being stalled. C1 Penn State Univ, Rotorcraft Ctr Excellence, Dept Aerosp Engn, University Pk, PA 16802 USA. NASA, Langley Res Ctr, USA, Vehicle Technol Directorate, Hampton, VA 23681 USA. RP Gandhi, F (reprint author), Penn State Univ, Rotorcraft Ctr Excellence, Dept Aerosp Engn, 229 Hammond Bldg, University Pk, PA 16802 USA. EM fgandhi@psu.edu NR 12 TC 5 Z9 5 U1 1 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD MAR PY 2004 VL 42 IS 3 BP 501 EP 512 DI 10.2514/1.575 PG 12 WC Engineering, Aerospace SC Engineering GA 803MJ UT WOS:000220234900009 ER PT J AU Tou, JCL Grindeland, RE Wade, CE AF Tou, JCL Grindeland, RE Wade, CE TI Effects of diet and exposure to hindlimb suspension on estrous cycling in Sprague-Dawley rats SO AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM LA English DT Article DE hypogravity; estrogen; reproduction; stress; phytoestrogen ID SPACE-FLIGHT; ESTROGENIC ACTIVITY; MOUSE BIOASSAY; RODENT DIETS; STRESS; PROTEIN; CASEIN; MICROGRAVITY; HEALTH; MODELS AB Various factors can disrupt the female reproductive cycle resulting in subfertility. The primary objective of this study was to determine whether physiological changes associated with exposure to hypogravity disrupt reproductive cycles. The hindlimb suspension (HLS) model was used to simulate the major physiological effects of hypogravity in female Sprague-Dawley rats. Also, to determine whether diet may influence reproductive results, rats were fed purified American Institute of Nutrition (AIN)-93G or chow diet. Rats (n = 9-11/group) subjected to HLS had lengthened estrous cycles due to prolonged diestrus, indicating hypoestrogenism. Interestingly, HLS rats fed AIN-93G but not chow diet had significantly reduced time spent in estrus and decreased plasma estradiol. Attenuation of hypoestrogenism in the chow-fed rats suggested that diet provided an exogenous source of estrogen. The mechanism involved in the disruption of estrous cycling remains to be determined. HLS increased urinary corticosterone (CORT) levels during the initial 4 days of HLS, suggesting that physiological responses to acute stress may be a potential mechanism in the disruption of estrous cycles. Higher basal urinary CORT was observed in rats fed chow vs. AIN-93G diet. HLS resulted in increased urinary, CORT. However, two-way ANOVA indicated a significant HLS effect (P < 0.001) but no effect of HLS X diet effect on urinary CORT levels, suggesting that estrogenic activity associated with the chow diet did not enhance the stress response. The results of this study indicate that HLS, diet, and the combination of HLS and diet influence estrous cycling. This has important implications for future reproductive success in the hypogravity environment of space. C1 NASA, Wyle Labs, Div Life Sci, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Tou, JCL (reprint author), NASA, Wyle Labs, Div Life Sci, Ames Res Ctr, MS 239-11, Moffett Field, CA 94035 USA. EM jtou@mail.arc.nasa.gov NR 39 TC 9 Z9 10 U1 0 U2 1 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0193-1849 J9 AM J PHYSIOL-ENDOC M JI Am. J. Physiol.-Endocrinol. Metab. PD MAR PY 2004 VL 286 IS 3 BP E425 EP E433 DI 10.1152/ajpendo.00287.2003 PG 9 WC Endocrinology & Metabolism; Physiology SC Endocrinology & Metabolism; Physiology GA 776XP UT WOS:000189144900014 PM 14625203 ER PT J AU Luttge, A Conrad, PG AF Luttge, A Conrad, PG TI Direct observation of microbial inhibition of calcite dissolution SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID CRYSTAL DISSOLUTION; MINERAL SURFACES; CARBONATE; KINETICS; MODEL; MANGANESE; REDUCTION; BACTERIA; GROWTH; RATES AB Vertical scanning interferometry (VSI) provides a method for quantification of surface topography at the angstrom to nanometer level. Time-dependent VSI measurements can be used to study the surface-normal retreat across crystal and other solid surfaces during dissolution or corrosion processes. Therefore, VSI can be used to directly and nondestructively measure mineral dissolution rates with high precision. We have used this method to compare the abiotic dissolution behavior of a representative calcite (CaCO3) cleavage face with that observed upon addition of an environmental microbe, Shewanella oneidensis MR-1, to the crystal surface. From our direct observations, we have concluded that the presence of the microbes results in a significant inhibition of the rate of calcite dissolution. This inhibition appears to be a 2nd-order effect that is related to the formation of etch pits. The opening of etch pits was greatly inhibited in the presence of added bacteria, suggesting that the bacterial cells exert their effect by inhibiting the formation of etch pits at high-energy sites at the crystal surface caused by lattice defects, e.g., screw or point dislocations. The experimental methodology thus provides a nondestructive, directly quantifiable, and easily visualized view of the interactions of microbes and minerals during weathering (or corrosion) processes or during mineral precipitation. C1 Rice Univ, Dept Earth Sci, Houston, TX 77005 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Luttge, A (reprint author), Rice Univ, Dept Earth Sci MS126, Houston, TX 77251 USA. EM aluttge@rice.edu RI Luttge, Andreas/A-2560-2011 OI Luttge, Andreas/0000-0002-5878-4026 NR 33 TC 47 Z9 49 U1 1 U2 18 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD MAR PY 2004 VL 70 IS 3 BP 1627 EP 1632 DI 10.1128/AEM.70.3.1627-1632.2004 PG 6 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 802HO UT WOS:000220154800047 PM 15006787 ER PT J AU Qiu, YM Uhl, D AF Qiu, YM Uhl, D TI Self-assembled InAsSb quantum dots on (001) InP substrates SO APPLIED PHYSICS LETTERS LA English DT Article ID 1.3 MU-M; ROOM-TEMPERATURE; DASH LASERS; LAYER AB Self-assembled InAsSb quantum dots (QD) on (001) InP substrates have been grown using metalorganic vapor phase epitaxy. The dot density and size are found to be strongly dependent on the presence of arsine. Direct deposition of InSb on InP and GaSb substrates formed large islands of InSb with low density of less than 5x10(9)/cm(2), however, InAsSb QDs of density as high as 4x10(10)/cm(2) could be self-assembled by alternating group III and group V precursors, and high density almost pure InSb QDs were achieved on In0.53Ga0.47As/InP. The formation of high density InAsSb QDs is a result of a local nonequilibrium process and a reduction in mobility of In adatoms on the growth surface due to the presence of arsenic atoms, and in the case of high density almost pure InSb QDs on InGaAs/InP, the InAs interface layer is believed to be responsible. Photoluminescence shows that InSb QDs emit light at room temperature in the range of 1.7-2.2 mum. (C) 2004 American Institute of Physics. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Qiu, YM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM yueming.qiu@jpl.nasa.gov NR 14 TC 34 Z9 34 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 1 PY 2004 VL 84 IS 9 BP 1510 EP 1512 DI 10.1063/1.1655690 PG 3 WC Physics, Applied SC Physics GA 778WJ UT WOS:000189264100026 ER PT J AU Schmidt, G AF Schmidt, G TI Astrobiolog, target of opportunity: The Leonid storms SO ASTROBIOLOGY LA English DT Article C1 NASA, Ames Res Ctr, Lead Astrobiol Integrat Off, Moffett Field, CA 94035 USA. RP Schmidt, G (reprint author), NASA, Ames Res Ctr, Lead Astrobiol Integrat Off, Mail Stop 19-25, Moffett Field, CA 94035 USA. EM gschmidt@mail.arc.nasa.gov NR 8 TC 1 Z9 1 U1 0 U2 1 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1531-1074 J9 ASTROBIOLOGY JI Astrobiology PD SPR PY 2004 VL 4 IS 1 BP 65 EP 66 DI 10.1089/153110704773600230 PG 2 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 835DY UT WOS:000222461700005 PM 15104903 ER PT J AU Jenniskens, P Schaller, EL Laux, CO Wilson, MA Schmidt, G Rairden, RL AF Jenniskens, P Schaller, EL Laux, CO Wilson, MA Schmidt, G Rairden, RL TI Meteors do not break exogenous organic molecules into high yields of diatomics SO ASTROBIOLOGY LA English DT Article DE prebiotic chemistry; origin of life; meteors; exogenous organics ID INTERPLANETARY DUST PARTICLES; LEONID METEORS; ATMOSPHERIC ENTRY; EARLY EARTH; ORIGIN; CARBON; MICROMETEORITES; ACCRETION; DELIVERY; NITROGEN AB Meteoroids that dominate the Earth's extraterrestrial mass influx (50-300 mum size range) may have contributed a unique blend of exogenous organic molecules at the time of the origin of life. Such meteoroids are so large that most of their mass is ablated in the Earth's atmosphere. In the process, organic molecules are decomposed and chemically altered to molecules differently from those delivered to the Earth's surface by smaller ( < 50 mum) micrometeorites and larger ( > 10 cm) meteorites. The question addressed here is whether the organic matter in these meteoroids is fully decomposed into atoms or diatomic compounds during ablation. If not, then the ablation products made available for prebiotic organic chemistry, and perhaps early biology, might have retained some memory of their astrophysical nature. To test this hypothesis we searched for CN emission in meteor spectra in an airborne experiment during the 2001 Leonid meteor storm. We found that the meteor's light-emitting air plasma, which included products of meteor ablation, contained less than 1 CN molecule for every 30 meteoric iron atoms. This contrasts sharply with the nitrogen/iron ratio of 1:1.2 in the solid matter of comet 1P/Halley. Unless the nitrogen content or the abundance of complex organic matter in the Leonid parent body, comet 55P/Tempel-Tuttle, differs from that in comet 1P/Halley, it appears that very little of that organic nitrogen decomposes into CN molecules during meteor ablation in the rarefied flow conditions that characterize the atmospheric entry of meteoroids similar to50 mum-10 cm in size. We propose that the organics of such meteoroids survive instead as larger compounds. C1 SETI Inst, Ctr Study Life Universe, Mountain View, CA 94043 USA. Dartmouth Coll, Hanover, NH 03755 USA. Stanford Univ, Dept Mech Engn, High Temp Gasdynam Lab, Stanford, CA 94305 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Lockheed Martin Space Sci Lab, Palo Alto, CA USA. RP Jenniskens, P (reprint author), SETI Inst, Ctr Study Life Universe, 2035 Landings Dr, Mountain View, CA 94043 USA. EM pjenniskens@mail.arc.nasa.gov NR 47 TC 22 Z9 22 U1 1 U2 5 PU MARY ANN LIEBERT INC PI NEW ROCHELLE PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA SN 1531-1074 J9 ASTROBIOLOGY JI Astrobiology PD SPR PY 2004 VL 4 IS 1 BP 67 EP 79 DI 10.1089/153110704773600249 PG 13 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 835DY UT WOS:000222461700006 PM 15104904 ER PT J AU Jenniskens, P Laux, CO Wilson, MA Schaller, EL AF Jenniskens, P Laux, CO Wilson, MA Schaller, EL TI The mass and speed dependence of meteor air plasma temperatures SO ASTROBIOLOGY LA English DT Article DE prebiotic molecules; origin of life; meteors; plasma temperatures; multiphase medium ID ORGANIC-MOLECULES; SPECTRA; RADIATION; DELIVERY; BOLIDES; MATTER; WAKE AB The speed and mass dependence of meteor air plasma temperatures is perhaps the most important data needed to understand how small meteoroids chemically change the ambient atmosphere in their path and enrich the ablated meteoric organic matter with oxygen. Such chemistry can play an important role in creating prebiotic compounds. The excitation conditions in various air plasma emissions were measured from high-resolution optical spectra of Leonid storm meteors during NASA's Leonid Multi-Instrument Aircraft Campaign. This was the first time a sufficient number and range of temperature measurements were obtained to search for meteoroid mass and speed dependencies. We found slight increases in temperature with decreasing altitude, but otherwise nearly constant values for meteoroids with speeds between 35 and 72 km/s and masses between 10(-5) g and 1 g. We conclude that faster and more massive meteoroids produce a larger emission volume, but not a higher air plasma temperature. We speculate that the meteoric plasma may be in multiphase equilibrium with the ambient atmosphere, which could mean lower plasma temperatures in a CO2-rich early Earth atmosphere. C1 SETI Inst, Ctr Study Life Universe, Mountain View, CA 94043 USA. Stanford Univ, Dept Mech Engn, High Temp Gasdynam Lab, Stanford, CA 94305 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Dartmouth Coll, NASA, Ames Astrobiol Acad, Hanover, NH 03755 USA. RP Jenniskens, P (reprint author), SETI Inst, Ctr Study Life Universe, 2035 Landings Dr, Mountain View, CA 94043 USA. EM pjenniskens@mail.arc.nasa.gov NR 33 TC 17 Z9 17 U1 0 U2 10 PU MARY ANN LIEBERT INC PI NEW ROCHELLE PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA SN 1531-1074 J9 ASTROBIOLOGY JI Astrobiology PD SPR PY 2004 VL 4 IS 1 BP 81 EP 94 DI 10.1089/153110704773600258 PG 14 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 835DY UT WOS:000222461700007 PM 15104905 ER PT J AU Jenniskens, P Laux, CO Schaller, EL AF Jenniskens, P Laux, CO Schaller, EL TI Search for the OH (Chi(2)Pi) Meinel band emission in meteors as a tracer of mineral water in comets: Detection of N-2(+) (Alpha-Chi) SO ASTROBIOLOGY LA English DT Article DE prebiotic molecules; origin of life; meteors; molecular band emission ID INTERPLANETARY DUST PARTICLES; ORGANIC-MOLECULES; EARLY EARTH; SPECTROSCOPY; NITROGEN; SYSTEM; DELIVERY; AIRGLOW; SPECTRA; IMPACT AB We report the discovery of the N-2(+) A-X Meinel band in the 780-840 nm meteor emission from two Leonid meteoroids that were ejected less than 1,000 years ago by comet 55P/Tempel-Tuttle. Our analysis indicates that the N-2(+) molecule is at least an order of magnitude less abundant than expected, possibly as a result of charge transfer reactions with meteoric metal atoms. This new band was found while searching for rovibrational transitions in the (XII)-I-2 electronic ground state of OH (the OH Meinel band), a potential tracer of water bound to minerals in cometary matter. The electronic A-X transition of OH has been identified in other Leonid meteors. We did not detect this OH Meinel band, which implies that the excited A state is not populated by thermal excitation but by a mechanism that directly produces OH in low vibrational levels of the excited A(2)Sigma state. Ultraviolet dissociation of atmospheric or meteoric water vapor is such it mechanism, as is the possible combustion of meteoric organics. C1 SETI Inst, Ctr Study Life Universe, Mountain View, CA 94043 USA. Stanford Univ, Dept Mech Engn, High Temp Gasdynam Lab, Stanford, CA 94305 USA. Dartmouth Coll, NASA, Ames Astrobiol Acad, Hanover, NH 03755 USA. RP Jenniskens, P (reprint author), SETI Inst, Ctr Study Life Universe, 2035 Landings Dr, Mountain View, CA 94043 USA. EM pjenniskens@mail.arc.nasa.gov NR 65 TC 13 Z9 13 U1 0 U2 4 PU MARY ANN LIEBERT INC PI NEW ROCHELLE PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA SN 1531-1074 J9 ASTROBIOLOGY JI Astrobiology PD SPR PY 2004 VL 4 IS 1 BP 109 EP 121 DI 10.1089/153110704773600276 PG 13 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 835DY UT WOS:000222461700009 PM 15104907 ER PT J AU Jenniskens, P Mandell, AM AF Jenniskens, P Mandell, AM TI Hydrogen emission in meteors as a potential marker for the exogenous delivery of organics and water SO ASTROBIOLOGY LA English DT Article ID FIREBALL SPECTRUM; EARLY EARTH; MOLECULES; NITROGEN; SEARCH; COMETS; CARBON; LIFE; WAKE AB We detected hydrogen Balmer-alpha (H-alpha) emission in the spectra of bright meteors and investigated its potential use as a tracer for exogenous delivery of organic matter. We found that it is critical to observe the meteors with high enough spatial resolution to distinguish the 656.46 nm H-alpha emission from the 657.46 nm intercombination line of neutral calcium, which was bright in the meteor afterglow. The H-alpha line peak stayed in constant ratio to the atmospheric emissions of nitrogen during descent of the meteoroid. If all of the hydrogen originates in the Earth's atmosphere, the hydrogen atoms are expected to have been excited at T = 4,400 K. In that case, we measured an H2O abundance in excess of 150 +/- 20 ppm at 80-90 km altitude (assuming local thermodynamic equilibrium in the air plasma). This compares with an expected < 20 ppm from H2O in the gas phase. Alternatively, meteoric refractory organic matter (and water bound in meteoroid minerals) could have caused the observed H-alpha emission, but only if the line is excited in a hot T similar to10,000 K plasma component that is unique to meteoric ablation vapor emissions such as Si+. Assuming that the Si+ lines of the Leonid spectrum would need the same hot excitation conditions, and a typical [H]/[C] = 1 in cometary refractory organics, we calculated an abundance ratio [C]/[Si] = 3.9 +/- 1.4 for the dust of comet 55P/Tempel-Tuttle. This range agreed with the value of [C]/[Si] = 4.4 measured for comet 1P/Halley dust. Unless there is 10 times more water vapor in the upper atmosphere than expected, we conclude that a significant fraction of the hydrogen atoms in the observed meteor plasma originated in the meteoroid. C1 SETI Inst, Ctr Study Life Universe, Mountain View, CA 94043 USA. NASA, Ames Res Ctr, NASA Ames Astrobiol Acad, Moffett Field, CA 94035 USA. RP Jenniskens, P (reprint author), SETI Inst, Ctr Study Life Universe, 2035 Landings Dr, Mountain View, CA 94043 USA. EM pjenniskens@mail.arc.nasa.gov RI Mandell, Avi/F-9361-2012 NR 36 TC 11 Z9 11 U1 0 U2 1 PU MARY ANN LIEBERT INC PI NEW ROCHELLE PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA SN 1531-1074 J9 ASTROBIOLOGY JI Astrobiology PD SPR PY 2004 VL 4 IS 1 BP 123 EP 134 DI 10.1089/153110704773600285 PG 12 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 835DY UT WOS:000222461700010 PM 15104908 ER PT J AU Haisch, KE Greene, TP Barsony, M Stahler, SW AF Haisch, KE Greene, TP Barsony, M Stahler, SW TI A near-infrared multiplicity survey of class I flat-spectrum systems in six nearby molecular clouds SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : close; stars : formation; stars : pre-main-sequence ID YOUNG STELLAR OBJECTS; STAR-FORMING REGIONS; RHO-OPHIUCHI CLOUD; MAIN-SEQUENCE STARS; T-TAURI STARS; ORION TRAPEZIUM CLUSTER; CHAMELEON DARK CLOUD; HERBIG-HARO OBJECTS; SOLAR-TYPE STARS; SERPENS CLOUD AB We present new near-IR observations of 76 Class I/flat-spectrum objects in the nearby (d less than or similar to 320 pc) Perseus, Taurus, Chamaeleon I and II, rho Ophiuchi, and Serpens dark clouds. These observations are part of a larger systematic infrared multiplicity survey of self-embedded objects in the nearest dark clouds. When combined with the results of our previously published near-infrared multiplicity survey, we find a restricted companion star fraction of 14/79 (18% +/- 4%) of the sources surveyed to be binary or higher order multiple systems over a separation range of similar to 300 - 2000 AU with a magnitude difference DeltaK less than or equal to 4 and with no correction for background contamination or completeness. This is consistent with the fraction of binary/multiple systems found among older pre-main-sequence T Tauri stars in each of the Taurus, rho Oph, and Chamaeleon star-forming regions over a similar separation range, as well as the combined companion star fraction for these regions. However, the companion star fraction for solar-type, and lower mass M dwarf, main-sequence stars in the solar neighborhood in this separation range (11% +/- 3%) is approximately one-half that of our sample. Together with multiplicity statistics derived for previously published samples of Class 0 and Class I sources, our study suggests that a significant number of binary/multiple objects may remain to be discovered at smaller separations among our Class I/flat-spectrum sample and/or most of the evolution of binary/multiple systems occurs during the Class 0 phase of early stellar evolution. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Haisch, KE (reprint author), Univ Michigan, Dept Astron, 830 Dennison Bldg, Ann Arbor, MI 48109 USA. EM khaisch@mail.arc.nasa.gov; tgreene@mail.arc.nasa.gov; mbarsony@stars.sfsu.edu; sstahler@astro.berkeley.edu NR 74 TC 46 Z9 46 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAR PY 2004 VL 127 IS 3 BP 1747 EP 1754 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 801FL UT WOS:000220081700040 ER PT J AU Werner, N in't Zand, JJM Natalucci, L Markwardt, CB Cornelisse, R Bazzano, A Cocchi, M Heise, J Ubertini, P AF Werner, N in't Zand, JJM Natalucci, L Markwardt, CB Cornelisse, R Bazzano, A Cocchi, M Heise, J Ubertini, P TI X-ray spectral evolution of SAX J1747.0-2853 during outburst activity and confirmation of its transient nature SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE accretion, accretion disks; X-rays : binaries; X-rays : bursts; X-rays : individual : SAX J1747.0-2853 ID GALACTIC-CENTER REGION; ENERGY CONCENTRATOR SPECTROMETER; ASTRONOMY SATELLITE; ON-BOARD; BEPPOSAX; EMISSION; SAX-J1747.0-2853; INSTABILITY; GX-339-4; BURSTER AB SAX J1747.0-2853 is an X-ray transient which exhibited X-ray outbursts yearly between 1998 and 2001, and most probably also in 1976. The outburst of 2000 was the longest and brightest. We have analyzed X-ray data sets that focus on the 2000 outburst and were obtained with BeppoSAX, XMM-Newton and RXTE. The data cover unabsorbed 2-10 keV fluxes between 0.1 and 5.3 x 10(-9) erg s(-1) cm(-2). The equivalent luminosity range is 6 x 10(35) to 2 x 10(37) erg s(-1). The 0.3-10 keV spectrum is well described by a combination of a multi-temperature disk blackbody, a hot Comptonization component and a narrow Fe-K emission line at 6.5 to 6.8 keV with an equivalent width of up to 285 eV. The hydrogen column density in the line of sight is (8.8 +/- 0.5) x 10(22) cm(-2) The most conspicuous spectral changes in this model are represented by variations of the temperature and radius of the inner edge of the accretion disk, and a jump of the equivalent width of the Fe-K line in one observation. Furthermore, 45 type-I X-ray bursts were unambiguously detected between 1998 and 2001 which all occurred during or close to outbursts. We derive a distance of 7.5 + 1.3 kpc which is consistent with previous determinations. Our failure to detect bursts for prolonged periods outside outbursts provides indirect evidence that the source returns to quiescence between outbursts and is a true transient. C1 Safarik Univ, Fac Sci, Kosice 04001, Slovakia. SRON, Natl Inst Space Res, NL-3584 CA Utrecht, Netherlands. Univ Utrecht, Astron Inst, NL-3508 TA Utrecht, Netherlands. CNR, Ist Astrofis Spaziale, Area Ric Roma Tor Vergata, I-00133 Rome, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Univ Southampton, Dept Phys & Astron, Southampton SO17 1BJ, Hants, England. RP Werner, N (reprint author), Safarik Univ, Fac Sci, Moyzesova 16, Kosice 04001, Slovakia. EM werner@ta3.sk OI Bazzano, Angela/0000-0002-2017-4396 NR 30 TC 19 Z9 19 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAR PY 2004 VL 416 IS 1 BP 311 EP 318 DI 10.1051/0004-6361:20034266 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 807XZ UT WOS:000220535500029 ER PT J AU Phillips, KJH Rainnie, JA Harra, LK Dubau, J Keenan, FP Peacock, NJ AF Phillips, KJH Rainnie, JA Harra, LK Dubau, J Keenan, FP Peacock, NJ TI Improved data for solar flare X-ray spectral analysis SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : flares; Sun : X-rays; gamma rays; X-rays : spectra ID HELIUM-LIKE IONS; DIELECTRONIC SATELLITE SPECTRA; ELECTRON-IMPACT-EXCITATION; RATE COEFFICIENTS; INNER-SHELL; HE-LIKE; RATES; IRON; PLASMAS; IONIZATION AB The inclusion of collisional rates for He-like Fe and Ca ions is discussed with reference to the analysis of solar flare Fe XXV and Ca XIX line emission, particularly from the Yohkoh Bragg Crystal Spectrometer (BCS). The new data are a slight improvement on calculations presently used in the BCS analysis software in that the discrepancy in the Fe XXV y and z line intensities (observed larger than predicted) is reduced. Values of electron temperature from satellite-to-resonance line ratios are slightly reduced (by up to 1 MK) for a given observed ratio. The new atomic data will be incorporated in the Yohkoh BCS databases. The data should also be of interest for the analysis of high-resolution, non-solar spectra expected from the Constellation-X and Astro-E space missions. A comparison is made of a tokamak S XV spectrum with a synthetic spectrum using atomic data in the existing software and the agreement is found to be good, so validating these data for particularly high-n satellite wavelengths close to the S XV resonance line. An error in a data file used for analyzing BCS Fe XXVI spectra is corrected, so permitting analysis of these spectra. C1 NASA, Natl Res Council, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Rutherford Appleton Lab, Space Sci & Technol Dept, Didcot OX11 0QX, Oxon, England. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Observ Paris, F-92195 Meudon, France. Queens Univ Belfast, Dept Phys, Belfast BT7 1NN, Antrim, North Ireland. EURATOM, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. RP Phillips, KJH (reprint author), NASA, Natl Res Council, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM phillips@stars.gsfc.nasa.gov OI Harra, Louise/0000-0001-9457-6200 NR 26 TC 7 Z9 7 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAR PY 2004 VL 416 IS 2 BP 765 EP 773 DI 10.1051/0004-6361:20034315 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 811PG UT WOS:000220783200033 ER PT J AU Richard, D Davis, SS AF Richard, D Davis, SS TI A note on transition, turbulent length scales and transport in differentially rotating flows SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE hydrodynamics; instabilities; turbulence ID HYDRODYNAMIC SHEAR TURBULENCE; ACCRETION DISKS; TRANSIENT GROWTH; KEPLERIAN DISKS; INSTABILITY; VISCOSITY; MODELS; DISCS AB In this note we address the issue of hydrodynamical instabilities in Astrophysical rotating shear flows in the light of recent publications focused on the possibility for differential rotation to trigger and sustain turbulence in the absence of a magnetic field. We wish to present in a synthetic form the major arguments in favor of this thesis along with a simple schematic scenario of the transition to and self-sustenance of such turbulence. We also propose that the turbulent diffusion length scale scales as the local Rossby number of the mean flow. A new prescription for the turbulent viscosity is introduced. This viscosity reduces to the so-called beta-prescription in the case of velocity profiles with a constant Rossby number, which includes Keplerian rotating flows. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Richard, D (reprint author), NASA, Ames Res Ctr, MS 245-3, Moffett Field, CA 94035 USA. EM drichard@mail.arc.nasa.gov NR 21 TC 4 Z9 4 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAR PY 2004 VL 416 IS 3 BP 825 EP 827 DI 10.1051/0004-6361:20034519 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 809UP UT WOS:000220661900009 ER PT J AU Rudawy, P Phillips, KJH Gallagher, PT Williams, DR Rompolt, B Keenan, FP AF Rudawy, P Phillips, KJH Gallagher, PT Williams, DR Rompolt, B Keenan, FP TI Search for 1-10 Hz modulations in coronal emission with SECIS during the August 11, 1999 eclipse SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE eclipses; Sun : corona; waves; magnetohydrodynamics (MHD) ID TOTAL SOLAR ECLIPSE; HIGH-FREQUENCY OSCILLATIONS; SHORT-PERIOD WAVES; QUIET SUN; BRIGHTENINGS; NANOFLARES; HEAT AB Results of the search of the periodic changes of the 530.3 nm line intensity emitted by selected structures of the solar corona in the frequency range 1-10 Hz are presented. A set of 12 728 images of the section of the solar corona extending from near the north pole to the south-west were taken simultaneously in the 530.3 nm ("green") line and white-light with the Solar Eclipse Coronal Imaging System (SECIS) during the 143-seconds-long totality of the 1999 August 11 solar eclipse observed in Shabla, Bulgaria. The time resolution of the collected data is better than 0.05 s and the pixel size is approximately 4 arcsec. Using classical Fourier spectral analysis tools, we investigated temporal changes of the local 530.3 nm coronal line brightness in the frequency range 1-10 Hz of thousands of points within the field of view. The various photometric and instrumental effects have been extensively considered. We did not find any indisputable, statistically significant evidence of periodicities in any of the investigated points (at significance level alpha = 0.05). C1 Univ Wroclaw, Astron Inst, PL-51622 Wroclaw, Poland. NASA, Natl Res Council, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, L3 Com Analyt Corp, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Queens Univ Belfast, Dept Pure & Appl Phys, Belfast BT7 1NN, Antrim, North Ireland. RP Univ Wroclaw, Astron Inst, Ul Kopernika 11, PL-51622 Wroclaw, Poland. EM rudawy@astro.uni.wroc.pl RI Williams, David/E-6676-2011; Gallagher, Peter/C-7717-2011 OI Williams, David/0000-0001-9922-8117; Gallagher, Peter/0000-0001-9745-0400 NR 32 TC 11 Z9 11 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAR PY 2004 VL 416 IS 3 BP 1179 EP 1186 DI 10.1051/0004-6361:20031737 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 809UP UT WOS:000220661900037 ER PT J AU de Martino, D Matt, G Belloni, T Haberl, F Mukai, K AF de Martino, D Matt, G Belloni, T Haberl, F Mukai, K TI BeppoSAX observations of soft X-ray intermediate polars SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE accretion, accretion discs; binaries : close; stars : individual : RE0751+144 (PQ Gem); RX J0558.0+5353 (V405 Aur); RX J1712.6-2414 (V2400 Oph); X-rays : binaries ID MAGNETIC CATACLYSMIC VARIABLES; AM-HERCULIS; PQ GEM; ROSAT OBSERVATIONS; WHITE-DWARF; GINGA DATA; EMISSION; ACCRETION; SPECTRUM; ASCA AB We present broad-band (0.1-90keV) spectral and temporal properties of the three Intermediate Polars, RE0751+144(PQGem),RX J0558.0+5353 (V405Aur) and RX J1712.6-2414(V2400 Oph) based on simultaneous soft and hard X-ray observations with the BeppoSAX satellite. The analysis of their spectra over the wide energy range of BeppoSAX instruments allows us to identify the soft and hard X-ray components and to determine simultaneously their temperatures. The black-body temperatures of the irradiated poles of the white dwarf atmosphere are found to be 60-100 eV, much higher than those found in their synchronous analogues, the Polars. The temperature of the optically thin post-shock plasma is well constrained in RX J1712.6-2414 and in RE 0751+144 (13 and 17 keV) and less precisely determined in RX J0558.0+5353. In the first two systems evidence of subsolar abundances is found, similarly to that estimated in other magnetic Cataclysmic Variables. A Compton reflection component is present in RX J0558.0+5353 and in RE 0751+144 and it is favoured in RX J1712.6-2414. Its origin is likely at the irradiated white dwarf surface. Although these systems share common properties (a soft X-ray component and optical polarized radiation), their X-ray power spectra and light curves at different energies suggest accretion geometries that cannot be reconciled with a single and simple configuration. C1 Osserv Astron Capodimonte, INAF, I-80131 Naples, Italy. Univ Studi Roma Tre, Dipartimento Fis, I-00146 Rome, Italy. Osserv Astron Brera, INAF, Merate, Italy. Max Planck Inst Extraterr Phys, D-85741 Garching, Germany. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP de Martino, D (reprint author), Osserv Astron Capodimonte, INAF, Via Moiariello 16, I-80131 Naples, Italy. EM demartino@na.astro.it; matt@fis.uniroma3.it; belloni@merate.mi.astro.it; fwh@mpe.mpg.de; mukai@milkyway.gsfc.nasa.gov OI de Martino, Domitilla/0000-0002-5069-4202 NR 41 TC 40 Z9 40 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAR PY 2004 VL 415 IS 3 BP 1009 EP 1019 DI 10.1051/0004-6361:20034160 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 773RH UT WOS:000188936200021 ER PT J AU Horan, D Badran, HM Bond, IH Boyle, PJ Bradbury, SM Buckley, JH Carter-Lewis, DA Catanese, M Celik, O Cui, W Daniel, M D'Vali, M Perez, IDC Duke, C Falcone, A Fegan, DJ Fegan, SJ Finley, JP Fortson, LF Gaidos, JA Gammell, S Gibbs, K Gillanders, GH Grube, J Hall, J Hall, TA Hanna, D Hillas, AM Holder, J Jarvis, A Jordan, M Kenny, GE Kertzman, M Kieda, D Kildea, J Knapp, J Kosack, K Krawczynski, H Krennrich, F Lang, MJ Le Bohec, S Linton, E Evans, JL Milovanovic, A Moriarty, P Muller, D Nagai, T Nolan, S Ong, RA Pallassini, R Petry, D Power-Mooney, B Quinn, J Quinn, M Ragan, K Rebillot, P Reynolds, PT Rose, HJ Schroedter, M Sembroski, GH Swordy, SP Syson, A Vassiliev, VV Wakely, SP Walker, G Weekes, TC Zweerink, J AF Horan, D Badran, HM Bond, IH Boyle, PJ Bradbury, SM Buckley, JH Carter-Lewis, DA Catanese, M Celik, O Cui, W Daniel, M D'Vali, M Perez, IDC Duke, C Falcone, A Fegan, DJ Fegan, SJ Finley, JP Fortson, LF Gaidos, JA Gammell, S Gibbs, K Gillanders, GH Grube, J Hall, J Hall, TA Hanna, D Hillas, AM Holder, J Jarvis, A Jordan, M Kenny, GE Kertzman, M Kieda, D Kildea, J Knapp, J Kosack, K Krawczynski, H Krennrich, F Lang, MJ Le Bohec, S Linton, E Evans, JL Milovanovic, A Moriarty, P Muller, D Nagai, T Nolan, S Ong, RA Pallassini, R Petry, D Power-Mooney, B Quinn, J Quinn, M Ragan, K Rebillot, P Reynolds, PT Rose, HJ Schroedter, M Sembroski, GH Swordy, SP Syson, A Vassiliev, VV Wakely, SP Walker, G Weekes, TC Zweerink, J TI Constraints on the very high energy emission from BL Lacertae objects SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL Lacertae objects : general; galaxies : jets; gamma rays : observations ID ACTIVE GALACTIC NUCLEI; GAMMA-RAY EMISSION; X-RAY; LAC OBJECTS; MARKARIAN 501; BLAZARS; MODEL; SEARCH; SAMPLE; JET AB We present results from observations of 29 BL Lacertae objects, taken with the Whipple Observatory 10 m gamma-ray telescope between 1995 and 2000. The observed objects are mostly at low redshift (z<0.2), but observations of objects of up to z=0.444 are also reported. Five of the objects are EGRET sources and two are unconfirmed TeV sources. Three of the confirmed sources of extragalactic TeV gamma rays were originally observed as part of this survey and have been reported elsewhere. No significant excesses are detected from any of the other objects observed, on timescales of days, months, or years. We report 99.9% confidence level flux upper limits for the objects for each observing season. The flux upper limits are typically 20% of the Crab flux, although for some sources, limits as sensitive as 6% of the Crab flux were derived. The results are consistent with the synchrotron self-Compton model predictions considered in this work. C1 Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. Tanta Univ, Dept Phys, Tanta, Egypt. Univ Leeds, Dept Phys, Leeds LS2 9JT, W Yorkshire, England. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Washington Univ, Dept Phys, St Louis, MO 63130 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Grinnell Coll, Dept Phys, Grinnell, IA 50112 USA. Natl Univ Ireland, Expt Phys Dept, Dublin 4, Ireland. Natl Univ Ireland, Dept Phys, Galway, Ireland. Univ Utah, High Energy Astrophys Inst, Salt Lake City, UT 84112 USA. Univ Arkansas, Dept Phys & Astron, Little Rock, AR 72204 USA. McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. DePauw Univ, Dept Phys & Astron, Greencastle, IN 46135 USA. Galway Mayo Inst Technol, Sch Sci, Galway, Ireland. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Cork Inst Technol, Dept Appl Phys & Instrumentat, Cork, Ireland. RP Horan, D (reprint author), Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, POB 97, Amado, AZ 85645 USA. EM dhoran@cfa.harvard.edu RI Hall, Jeter/E-9294-2015; Daniel, Michael/A-2903-2010; OI Daniel, Michael/0000-0002-8053-7910; Cui, Wei/0000-0002-6324-5772; Knapp, Johannes/0000-0003-1519-1383; Lang, Mark/0000-0003-4641-4201 NR 69 TC 47 Z9 47 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2004 VL 603 IS 1 BP 51 EP 61 DI 10.1086/381430 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 779ZM UT WOS:000189343900008 ER PT J AU Turner, TJ Kraemer, SB Reeves, JN AF Turner, TJ Kraemer, SB Reeves, JN TI Transient relativistically shifted lines as a probe of black hole systems SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; galaxies : active; galaxies : individual (Markarian 766); stars : individual (Cygnus X-1) ID ACTIVE GALACTIC NUCLEI; GALAXIES; DISK; EMISSION; PROFILE; OUTFLOW AB X-ray spectra of Seyfert galaxies have revealed a new type of X-ray spectral feature, one that appears to offer important new insight into the black hole system. XMM revealed several narrow emission lines redward of Fe Kalpha in NGC 3516. Since that discovery the phenomenon has been observed in other Seyfert galaxies, e. g., NGC 7314 and ESO 198-G24. We present new evidence for a redshifted Fe line in XMM spectra of Mrk 766. These data reveal the first evidence for a significant shift in the energy of such a line, occurring over a few tens of kiloseconds. This shift may be interpreted as deceleration of an ejected blob of gas traveling close to the escape velocity. C1 Univ Maryland Baltimore Cty, Dept Phys, Joint Ctr Astrophys, Baltimore, MD 21250 USA. NASA, High Energy Astrophys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Catholic Univ Amer, NASA, GSFC, Greenbelt, MD 20771 USA. RP Turner, TJ (reprint author), Univ Maryland Baltimore Cty, Dept Phys, Joint Ctr Astrophys, 1000 Hilltop Circle, Baltimore, MD 21250 USA. NR 19 TC 51 Z9 51 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2004 VL 603 IS 1 BP 62 EP 66 DI 10.1086/381312 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 779ZM UT WOS:000189343900009 ER PT J AU Harrus, IM Slane, PO Hughes, JP Plucinsky, PP AF Harrus, IM Slane, PO Hughes, JP Plucinsky, PP TI An X-ray study of the supernova remnant G18.95-1.1 SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : abundances; ISM : individual (G18.95-1.1); supernova remnants; X-rays : ISM ID RADIO-SOURCE; ABUNDANCES; EMISSION; STARS AB We present an analysis of data from both the Rontgen Satellite (ROSAT) and the Advanced Satellite for Cosmology and Astrophysics (ASCA) of the supernova remnant G18.95-1.1. We find that the X-ray emission from G18.95-1.1 is predominantly thermal, heavily absorbed with a column density around 10(22) atoms cm(-2), and can be best described by an nonequilibrium ionization (NEI) model with a temperature around 0.9 keV and an ionization timescale of 1.1x10(10) cm(-3) s(-1). We find only marginal evidence for nonsolar abundances. Comparisons between 21 cm H I absorption data and derived parameters from our spectral analysis strongly suggest a relatively nearby remnant (a distance of about 2 kpc). Above 4 keV, we identify a small region of emission located at the tip of the central, flat-spectrum barlike feature in the radio image. We examine two possibilities for this emission region: a temperature variation within the remnant or a pulsar wind nebula (PWN). The current data do not allow us to distinguish between these possible explanations. In the scenario where this high-energy emission region corresponds to a PWN, our analysis suggests a rotational loss rate for the unseen pulsar of about 7x10(35) ergs s(-1) and a ratio L-r/L-X of about 3.6 for the entire PWN, slightly above the maximum ratio (3.4 for Vela) measured in known PWNe. C1 NASA, USRA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Rutgers State Univ, Piscataway, NJ 08854 USA. RP Harrus, IM (reprint author), NASA, USRA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM imh@lheapop.gsfc.nasa.gov NR 23 TC 6 Z9 6 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2004 VL 603 IS 1 BP 152 EP 158 DI 10.1086/381355 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 779ZM UT WOS:000189343900019 ER PT J AU Vaughan, S Willingale, R O'Brien, PT Osborne, JP Reeves, JN Levan, AJ Watson, MG Tedds, JA Watson, D Santos-Lleo, M Rodriguez-Pascual, PM Schartel, N AF Vaughan, S Willingale, R O'Brien, PT Osborne, JP Reeves, JN Levan, AJ Watson, MG Tedds, JA Watson, D Santos-Lleo, M Rodriguez-Pascual, PM Schartel, N TI The discovery of an evolving dust-scattered X-ray halo around GRB 031203 SO ASTROPHYSICAL JOURNAL LA English DT Article DE dust, extinction; Galaxy : structure; gamma rays : bursts; X-rays : general ID SMALL-ANGLE SCATTERING; GUM NEBULA; INTERSTELLAR GRAINS AB We report the first detection of a time-dependent dust-scattered X-ray halo around a gamma-ray burst (GRB). GRB 031203 was observed by XMM-Newton starting 6 hr after the burst. The halo appeared as concentric ringlike structures centered on the GRB location. The radii of these structures increased with time as, consistent with t(1/2) small-angle X-ray scattering caused by a large column of dust along the line of sight to a cosmologically distant GRB. The rings are due to dust concentrated in two distinct slabs in the Galaxy located at distances of 880 and 1390 pc, consistent with known Galactic features. The halo brightness implies an initial soft X-ray pulse consistent with the observed GRB. C1 Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Univ Copenhagen, Niels Bohr Inst Astron Phys & Geophys, DK-2100 Copenhagen O, Denmark. XMM Newton SOC, E-28080 Madrid, Spain. RP Vaughan, S (reprint author), Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England. EM sav2@star.le.ac.uk; rw@star.le.ac.uk; pto@star.le.ac.uk; julo@star.le.ac.uk; jnr@milkyway.gsfc.nasa.gov; anl@star.le.ac.uk; mgw@star.le.ac.uk; jat@star.le.ac.uk; darach@astro.ku.dk; msantos@xmm.vilspa.esa.es; prodrigu@xmm.vilspa.esa.es; norbert.schartel@esa.int RI Watson, Darach/E-4521-2015 OI Tedds, Jonathan/0000-0003-2829-4584; Watson, Darach/0000-0002-4465-8264 NR 28 TC 61 Z9 62 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2004 VL 603 IS 1 BP L5 EP L8 DI 10.1086/382785 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 779ZN UT WOS:000189344000002 ER PT J AU Eriksen, HK Lilje, PB Banday, AJ Gorski, KM AF Eriksen, HK Lilje, PB Banday, AJ Gorski, KM TI Estimating N-point correlation functions from pixelized sky maps SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE cosmic microwave background; methods : statistical ID 3-POINT CORRELATION-FUNCTION; ANGULAR-CORRELATION FUNCTION; LARGE-SCALE STRUCTURE; CROSS-CORRELATION; GALAXIES AB We develop, implement and test a set of algorithms for estimating N-point correlation functions from pixelized sky maps. These algorithms are slow, in the sense that they do not break the Od(N-pix(N)) barrier, and yet, they are fast enough for efficient analysis of data sets up to several hundred thousand pixels. The typical application of these methods is Monte Carlo analysis using several thousand realizations, and therefore we organize our programs so that the initialization cost is paid only once. The effective cost is then reduced to a few additions per pixel multiplet (pair, triplet, etc.). Further, the algorithms waste no CPU time on computing undesired geometric configurations, and, finally, the computations are naturally divided into independent parts, allowing for trivial (i.e., optimal) parallelization. C1 Univ Oslo, Inst Theoret Astrophys, N-0315 Oslo, Norway. Max Planck Inst Astrophys, D-85741 Garching, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Oslo, Ctr Math Applicat, N-0316 Oslo, Norway. Univ Warsaw Observ, PL-00478 Warsaw, Poland. RP Univ Oslo, Inst Theoret Astrophys, POB 1029 Blindern, N-0315 Oslo, Norway. EM h.k.k.eriksen@astro.uio.no; per.lilje@astro.uio.no; banday@mpa-garching.mpg.de; krzysztof.m.gorski@jpl.nasa.gov RI Lilje, Per/A-2699-2012; OI Lilje, Per/0000-0003-4324-7794 NR 24 TC 10 Z9 10 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 EI 1538-4365 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD MAR PY 2004 VL 151 IS 1 BP 1 EP 11 DI 10.1086/381740 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 801TL UT WOS:000220118100001 ER PT J AU Ridley, B Atlas, E Selkirk, H Pfister, L Montzka, D Walega, J Donnelly, S Stroud, V Richard, E Kelly, K Tuck, A Thompson, T Reeves, J Baumgardner, D Rawlins, WT Mahoney, M Herman, R Friedl, R Moore, F Ray, E Elkins, J AF Ridley, B Atlas, E Selkirk, H Pfister, L Montzka, D Walega, J Donnelly, S Stroud, V Richard, E Kelly, K Tuck, A Thompson, T Reeves, J Baumgardner, D Rawlins, WT Mahoney, M Herman, R Friedl, R Moore, F Ray, E Elkins, J TI Convective transport of reactive constituents to the tropical and rigid-latitude tropopause region: I. Observations SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE convection; aircraft measurements; tropical tropopause; nitrogen oxides; hydrocarbons; methyl iodide; methyl nitrate; upper troposphere; lower stratosphere; chemical tracers ID UPPER TROPOSPHERE; LOWER STRATOSPHERE; NITROGEN-OXIDES; BOUNDARY-LAYER; NUMERICAL SIMULATIONS; CLOUD TRANSPORT; CIRRUS CLOUDS; WATER-VAPOR; OZONE; CHEMISTRY AB Measurements of ozone, reactive carbon and nitrogen, and other trace constituents from flights of the NASA WB-57F aircraft in the upper troposphere and lower stratosphere reveal that convection in the tropics can present a complex mix of surface-emitted constituents right up to the altitude of the lapse rate tropopause. At higher latitudes over the southern US, the strongest transport signal, in terms of constituent mixing ratios, occurred in the potential temperature range of 340-350 K or approximately over the altitude range of 9-11 km. Weaker convective signals were also seen up to near the tropopause. There was no evidence of convective transport directly into the lower stratosphere from these flights. (C) 2003 Elsevier Ltd. All rights reserved. C1 Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. Bay Area Environm Res Inst, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NOAA, Aeron Lab, Boulder, CO 80305 USA. Univ Denver, Dept Engn, Denver, CO 80208 USA. Univ Nacl Autonoma Mexico, Mexico City 04510, DF, Mexico. Phys Sci Inc, Andover, MA 01810 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. RP Atlas, E (reprint author), Natl Ctr Atmospher Res, Div Atmospher Chem, POB 3000, Boulder, CO 80307 USA. EM eatlas@rsmas.miami.edu RI Herman, Robert/H-9389-2012; Tuck, Adrian/F-6024-2011; Ray, Eric/D-5941-2013; Atlas, Elliot/J-8171-2015 OI Herman, Robert/0000-0001-7063-6424; Tuck, Adrian/0000-0002-2074-0538; Ray, Eric/0000-0001-8727-9849; NR 48 TC 21 Z9 22 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 EI 1873-2844 J9 ATMOS ENVIRON JI Atmos. Environ. PD MAR PY 2004 VL 38 IS 9 BP 1259 EP 1274 DI 10.1016/j.atmosenv.2003.11.038 PG 16 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 776DT UT WOS:000189102000003 ER PT J AU Shi, SJ South, DA Meck, JV AF Shi, SJ South, DA Meck, JV TI Fludrocortisone does not prevent orthostatic hypotension in astronauts after spaceflight SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE hemodynamic; hypovolemia; mineralocorticoid; presyncopal; sympathetic activity ID CARBON-MONOXIDE; BLOOD; INTOLERANCE; MANAGEMENT; RELEASE; HUMANS AB Background: During stand/tilt tests after spaceflight, 20% of astronauts experience orthostatic hypotension and presyncope. Spaceflight-induced hypovolemia is a contributing factor. Fludrocortisone, a synthetic mineralocorticoid, has been shown to increase plasma volume and orthostatic tolerance in Earth-bound patients. The efficacy of fludrocortisone as a treatment for postflight hypovolemia and orthostatic by potension in astronauts has not been studied. Our purpose was to test the hypothesis that astronauts who ingest fludrocortisone prior to landing would have less loss of plasma volume and greater orthostatic tolerance than astronauts who do not ingest fludrocortisone. Methods: There were 25 male astronauts who were randomized into 2 groups: placebo (n = 18) and fludrocortisone (n = 7), and participated in stand tests 10 d before launch and 2-4 h after landing. Subjects took either 0.3 mg fludrocortisone or placebo orally 7 h prior to landing. Supine plasma and red cell volumes, supine and standing HR, arterial pressure, aortic outflow, and plasma norepinephrine and epinephrine were measured. Results: On landing day, 2 of 18 in the placebo group and 1 of 7 in the fludrocortisone group became presyncopal (chi(2) = 0.015, p = 0.90). Plasma volumes were significantly decreased after flight in the placebo group, but not in the fludrocortisone group. During postflight stand tests, standing plasma norepinephrine was significantly less in the fludrocortisone group compared with the placebo group. Conclusions: Treatment with a single dose of fludrocortisone results in protection of plasma volume but no protection of orthostatic tolerance. Fludrocortisone is not recommended as a countermeasure for spaceflight-induced orthostatic intolerance. C1 NASA, Lyndon B Johnson Space Ctr, Cardiovasc Lab, Human Adaptat & Countermeasures Off SK, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Wyle Labs, Houston, TX 77058 USA. RP Meck, JV (reprint author), NASA, Lyndon B Johnson Space Ctr, Cardiovasc Lab, Human Adaptat & Countermeasures Off SK, 2101 NASA Pkwy, Houston, TX 77058 USA. EM jmeck@ems.jsc.nasa.gov NR 20 TC 10 Z9 12 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 2004 VL 75 IS 3 BP 235 EP 239 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 809OJ UT WOS:000220645700007 PM 15018291 ER PT J AU Hamilton, DR Sargsyan, AE Kirkpatrick, AW Nicolaou, S Campbell, M Dawson, DL Melton, SL Beck, G Guess, T Rasbury, J Dulchavsky, SA AF Hamilton, DR Sargsyan, AE Kirkpatrick, AW Nicolaou, S Campbell, M Dawson, DL Melton, SL Beck, G Guess, T Rasbury, J Dulchavsky, SA TI Sonographic detection of pneumothorax and hemothorax in microgravity SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE pneumothorax; hemothorax; ultrasound imaging; microgravity; space medicine; trauma; chest tube ID THORACIC ULTRASOUND; RADIOGRAPHY; POPULATION; DIAGNOSIS; TRAUMA; SPACE AB Introduction: An intrathoracic injury may be disastrous to a crewmember aboard the International Space Station (ISS) if the diagnosis is missed or delayed. Symptomatic or clinically suspicious thoracic trauma is treated as a surgical emergency on Earth, usually with immediate stabilization and rapid transport to a facility that is able to deliver the appropriate medical care. A similar approach is planned for the ISS; however, an unnecessary evacuation would cause a significant mission impact and an exorbitant expense. Hypothesis: The use of ultrasound imaging for the detection of pneumothorax and hemothorax in microgravity is both possible and practical. Methods: Sonography was performed on anesthetized pigs in a ground-based laboratory (n = 4) and microgravity conditions (0 G) during parabolic flight (n = 4). Aliquots of air (50-500 ml) or saline (10-200 ml) were introduced into the pleural space to simulate pneurnothorax and hemothorax, respectively. Results. The presence of "lung sliding" excluded pnemothorax. In microgravity, a loss of "lung sliding" was noted simultaneously in the anterior and posterior sonographic windows after 100 ml of air was introduced into the chest, indicating pneumothorax. The presence of the fluid layer in simulated hemothorax was noted in the anterior and posterior sonographic windows after 50 ml of fluid was injected into the pleural space. During the microgravity phase, the intrapleural fluid rapidly redistributed so that it could be detected using either anterior or posterior sonographic windows. Conclusion: Modest to severe pneurnothorax and hemothorax can be diagnosed using ultrasound in microgravity. C1 NASA, Adv Projects, Wyle Labs, Houston, TX 77058 USA. Foothills Med Ctr, Calgary, AB, Canada. Henry Ford Hosp, Detroit, MI 48202 USA. UC Davis, Div Vasc Surg, Sacramento, CA USA. Vancouver Hosp & Hlth Sci Ctr, Vancouver, BC, Canada. Impact Instrumentat Inc, W Caldwell, NJ USA. RP Hamilton, DR (reprint author), NASA, Adv Projects, Wyle Labs, 1290 Hercules Dr,Suite 120, Houston, TX 77058 USA. EM dhamilton@wylehou.com NR 18 TC 22 Z9 22 U1 1 U2 3 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 2004 VL 75 IS 3 BP 272 EP 277 PG 6 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 809OJ UT WOS:000220645700013 PM 15018297 ER PT J AU Friedl, KE Mallis, MM Ahlers, ST Popkin, SM Larkin, W AF Friedl, KE Mallis, MM Ahlers, ST Popkin, SM Larkin, W TI Research requirements for operational decision-making using models of fatigue and performance SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article; Proceedings Paper CT Fatigue and Performance Modeling Workshop CY JUN 13-14, 2002 CL Seattle, WA DE biological models; task performance and analysis; personnel staffing and scheduling; psychomotor performance; cognition; physiology; neuropsychological tests; sleep deprivation; fatigue; physiopathology; biomathematical models; alertness; performance ID SLEEP-DEPRIVATION; DOSE-RESPONSE; PSYCHOMOTOR VIGILANCE; CIRCADIAN-RHYTHMS; EXPOSURE; INVOLVEMENT; RESTRICTION; ALERTNESS; PATTERNS; CAFFEINE AB Sustained human performance is critical to job and mission success in many federal agencies including national defense, aerospace exploration, and transportation. For the responsible agencies, applications of the basic biomedical and applied human factors science provide the best available solutions to help individuals perform more effectively and with increased safety. Key products of this research are biomathematical models that predict periods of impaired performance, with applications in planning tools, real time monitoring, and intervention decision aids. Since it is difficult to quantify the number of judgment errors or accidents averted, metrics of success for fatigue management systems must be largely based on the accuracy of performance predictions derived from laboratory-based research studies and the extent to which such results can be generalized to the field environment. Performance metrics must, at a minimum, be correlated with occupational task performance to demonstrate relevance to real-world applications. This paper outlines broad goals for human effectiveness research related to fatigue, alertness, and performance. To advance from the present state of knowledge to useful predictive models requires a well-coordinated commitment from federal agencies. Users should be made aware that current models and tests are not likely to encompass all of the aspects of human performance that are relevant to field environments and occupations. C1 USA, Med Res & Mat Command, Frederick, MD 21702 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Off Naval Res, Arlington, VA 22217 USA. Volpe Ctr, Dept Transportat, Cambridge, MA USA. USAF, Off Sci Res, Arlington, VA USA. RP Friedl, KE (reprint author), POB 29, Natick, MA 01760 USA. EM karl.friedl@na.amedd.army.mil NR 26 TC 14 Z9 14 U1 1 U2 4 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 2004 VL 75 IS 3 SU 2 BP A192 EP A199 PG 8 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 811TI UT WOS:000220793800032 PM 15018284 ER PT J AU Mallis, MM Mejdal, S Nguyen, TT Dinges, DF AF Mallis, MM Mejdal, S Nguyen, TT Dinges, DF TI Summary of the key features of seven biomathematical models of human fatigue and performance SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article; Proceedings Paper CT Fatigue and Performance Modeling Workshop CY JUN 13-14, 2002 CL Seattle, WA DE biomathematical models; circadian rhythms; work/rest schedules; sleep; sleep loss; alertness; fatigue; performance ID SLEEP-DEPRIVATION; ALERTNESS; ACCIDENTS AB Background; Biomathematical models that quantify the effects of circadian and sleep/wake processes on the regulation of alertness and performance have been developed in an effort to predict the magnitude and timing of fatigue-related responses in a variety of contexts (e.g., transmeridian travel, sustained operations, shift work). This paper summarizes key features of seven biomathematical models reviewed as part of the Fatigue and Performance Modeling Workshop held in Seattle, WA, on June 13-14, 2002. The Workshop was jointly sponsored by the National Aeronautics and Space Administration, U.S. Department of Defense, U.S. Army Medical Research and Materiel Command, Office of Naval Research, Air Force Office of Scientific Research, and U.S. Department of Transportation. Methods. An invitation was sent to developers of seven biomathematical models that were commonly cited in scientific literature and/or supported by government funding. On acceptance of the invitation to attend the Workshop, developers were asked to complete a survey of the goals, capabilities, inputs, and outputs of their biomathematical models of alertness and performance. Data from the completed surveys were summarized and juxtaposed to provide a framework for comparing features of the seven models. Results: Survey responses revealed that models varied greatly relative to their reported goals and capabilities. While all modelers reported that circadian factors were key components of their capabilities, they differed markedly with regard to the roles of sleep and work times as input factors for prediction: four of the seven models had work time as their sole input variable(s), while the other three models relied on various aspects of sleep timing for model input. Models also differed relative to outputs: five sought to predict results from laboratory experiments, field, and operational data, while two models were developed without regard to predicting laboratory experimental results. All modelers provided published papers describing their models, with three of the models being proprietary. Conclusions: Although all models appear to have been fundamentally influenced by the two-process model of sleep regulation by Borbely (6), there is considerable diversity among them in the number and type of input and output variables, and their stated goals and capabilities. C1 San Jose State Univ, NASA, Ames Res Ctr, Syst Safety Res Branch, Moffett Field, CA 94035 USA. Monterey Technol, Fatigue Countermeasures Grp, Moffett Field, CA USA. Univ Penn, Sch Med, Dept Psychiat, Div Sleep & Chronobiol, Philadelphia, PA 19104 USA. RP Mallis, MM (reprint author), San Jose State Univ, NASA, Ames Res Ctr, Syst Safety Res Branch, MS-262-4, Moffett Field, CA 94035 USA. EM Melissa.M.Mallis@nasa.gov NR 42 TC 88 Z9 88 U1 0 U2 8 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 2004 VL 75 IS 3 SU 2 BP A4 EP A14 PG 11 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 811TI UT WOS:000220793800002 PM 15018262 ER PT J AU Baker, JD Johanos, TC AF Baker, JD Johanos, TC TI Abundance of the Hawaiian monk seal in the main Hawaiian Islands SO BIOLOGICAL CONSERVATION LA English DT Article DE Hawaiian monk seal; Monachus schauinslandi; abundance; body condition ID MONACHUS-SCHAUINSLANDI; PHOCA-VITULINA; NORTHWESTERN; EXTINCTION; SIZE; DIET; SHARK; JACKS; GEAR; MOAS AB Most of the extant circa 1400 Hawaiian monk seals Monachus schauinslandi live in the Northwestern Hawaiian Islands (NWHI). However, an increasing number of sightings and births have recently occurred in the main Hawaiian Islands (MHI), where no systematic surveys of monk seals were conducted prior to 2000. We estimate that there were at least 45 seals in the MHI in 2000 and at least 52 in 2001, based on aerial surveys of all MHI coastlines, supplemented by sightings of seals from the ground. Moreover, annual births in the MHI have evidently increased since the mid-1990s. Weaned pups in the MHI are longer and have greater girth than those in the NWHI, perhaps reflecting greater per-capita abundance of prey resources. We think that Hawaiian monk seals have recently re-colonized the MHI, which were a very likely part of their historic range. Regardless, the MHI habitat appears to be favorable for continued increases of this endangered species. Published by Elsevier Ltd. C1 NOAA, Natl Marine Fisheries Serv, Pacific Isl Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI 96822 USA. RP Baker, JD (reprint author), NOAA, Natl Marine Fisheries Serv, Pacific Isl Fisheries Sci Ctr, Honolulu Lab, 2570 Dole St, Honolulu, HI 96822 USA. EM jason.baker@noaa.gov NR 55 TC 31 Z9 37 U1 4 U2 31 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0006-3207 J9 BIOL CONSERV JI Biol. Conserv. PD MAR PY 2004 VL 116 IS 1 BP 103 EP 110 DI 10.1016/S0006-3207(03)00181-2 PG 8 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 763RD UT WOS:000188113500011 ER PT J AU McCollum, G Boyle, R AF McCollum, G Boyle, R TI Rotations in a vertebrate setting: evaluation of the symmetry group of the disynaptic canal-neck projection SO BIOLOGICAL CYBERNETICS LA English DT Article ID ANGULAR VESTIBULOOCULAR REFLEX; 6 SEMICIRCULAR CANALS; VESTIBULAR STIMULATION; SPATIAL ORIENTATION; EYE-MOVEMENTS; GALVANIC STIMULATION; PARASOLITARY NUCLEUS; POSTURAL RESPONSES; UVULA-NODULUS; SELF-MOTION AB Organizational structures intrinsic to nervous systems can be more precisely analyzed and compared with other logical structures once they are expressed in mathematical languages. A standard mathematical language for expressing organizational structure is that of groups. Groups are especially well suited to organizational structures involving multiple symmetries such as spatial structures. The vestibular system is widely believed to mediate many neural functions involving spatial structure. The vestibular nuclei receive direct projections from the vestibular endorgans, the semicircular canals and the otolith organs. The near-orthogonal directions of the semicircular canals are embedded in the bone. However, those canal directions are external to the nervous system. This study addresses the way the three-dimensional space of rotations is also embedded in the group structure of neural connectivity. Although we know a great deal about physical rotation, it is not clear that nervous systems organize rotations in the same way as physicists do. It would make sense for nervous systems to organize rotations in such a way as to provide physiologically relevant information about performing or compensating for rotations. The vestibular nuclei, which might be expected to display an organization that binds rotations into a rotation space, do not give a clear organization. This may be because of the multiplicity of spatial functions performed by the vestibular nuclei; rather than one spatial organization, the vestibular nuclei are likely to accommodate multiple, related spatial organizations. This study evaluates one particular data set from the literature that specifies the organization of the disynaptic canal-neck projection; other projections and neuronal populations may have other intrinsic organizations. The data are evaluated directly for their symmetry group. In the symmetry group, the vertebrate requirement that physiology have a right and left is found to be satisfied in two ways: (i) by a hexagonal symmetry arising from the right-left doubling of front and back, (ii) along with separate organizations on the two sides that may be required to operate independently to some extent. The eight observed muscle innervation patterns from the data are the complete set of possible combinations of inhibitory/excitatory polarities from three canal pairs. These eight innervation patterns are organized as the vertices of a cube. The two types of side muscles provide the vertical direction. As the head rotates in physical space, the cube rotates in sensorimotor space. Like the canal-neck projection, otolith projections and proprioceptive afferents contact both the vestibular nuclei and neck motoneurons. They may have a similar organization, perhaps with extensions of the same pattern. Otherwise, like a checkerboard superimposed over a paisley, they will form an overlapping organization with the disynaptic canal-neck projection. Further research is required to determine whether the sensorimotor spatial structure of the canal-neck projection is widespread in nervous systems or whether there are several complete structures that are fragmented and reintegrated. C1 Legacy Clin Res & Technol Ctr, Portland, OR 97232 USA. NASA, Ames Res Ctr, BioVIS Technol Ctr, Moffett Field, CA 94035 USA. RP McCollum, G (reprint author), Legacy Clin Res & Technol Ctr, 1225 NE 2nd Ave, Portland, OR 97232 USA. EM mccollum@ohsu.edu NR 59 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0340-1200 J9 BIOL CYBERN JI Biol. Cybern. PD MAR PY 2004 VL 90 IS 3 BP 203 EP 217 DI 10.1007/s00422-003-0461-3 PG 15 WC Computer Science, Cybernetics; Neurosciences SC Computer Science; Neurosciences & Neurology GA 807JL UT WOS:000220497700005 PM 15052483 ER PT J AU Chen, H Han, J Li, J Meyyappan, M AF Chen, H Han, J Li, J Meyyappan, M TI Microelectronic DNA assay for the detection of BRCA1 gene mutations SO BIOMEDICAL MICRODEVICES LA English DT Article DE microelectronic array; mutations; nanoelectronic array; cancer detection; carbon nanotubes; molecular diagnosis ID CANCER SUSCEPTIBILITY GENE; PROTEIN TRUNCATION TEST; OVARIAN-CANCER; BREAST-CANCER; FAMILIES AB Mutations in BRCA1 are characterized by predisposition to breast cancer, ovarian cancer and prostate cancer as well as colon cancer. Prognosis for this cancer survival depends upon the stage at which cancer is diagnosed. Reliable and rapid mutation detection is crucial for the early diagnosis and treatment. We developed an electronic assay for the detection of a representative single nucleotide polymorphism (SNP), deletion and insertion in BRCA1 gene by the microelectronics microarray instrumentation. The assay is rapid, and it takes 30 minutes for the immobilization of target DNA samples, hybridization, washing and readout. The assay is multiplexing since it is carried out at the same temperature and buffer conditions for each step. The assay is also highly specific, as the signal-to-noise ratio is much larger than recommended value (72.86 to 321.05 vs. 5) for homozygotes genotyping, and signal ratio close to the perfect value 1 for heterozygotes genotyping (1.04). C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. ELORET, Moffett Field, CA 94035 USA. RP Chen, H (reprint author), NASA, Ames Res Ctr, Mail Stop 229-1, Moffett Field, CA 94035 USA. EM hchen@mail.arc.nasa.gov RI Li, Jun/H-7771-2013 OI Li, Jun/0000-0002-3689-8946 NR 20 TC 10 Z9 10 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1387-2176 J9 BIOMED MICRODEVICES JI Biomed. Microdevices PD MAR PY 2004 VL 6 IS 1 BP 55 EP 60 DI 10.1023/B:BMMD.0000013366.85609.dd PG 6 WC Engineering, Biomedical; Nanoscience & Nanotechnology SC Engineering; Science & Technology - Other Topics GA 767CM UT WOS:000188422700007 PM 15307445 ER PT J AU Cavalieri, DJ Parkinson, CL Vinnikov, KY AF Cavalieri, DJ Parkinson, CL Vinnikov, KY TI 30-year trends in sea ice extent SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT News Item C1 NASA, GSFC, Greenbelt, MD 20771 USA. RP Cavalieri, DJ (reprint author), NASA, GSFC, Greenbelt, MD 20771 USA. RI Vinnikov, Konstantin/F-9348-2010; Parkinson, Claire/E-1747-2012 OI Parkinson, Claire/0000-0001-6730-4197 NR 0 TC 2 Z9 2 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAR PY 2004 VL 85 IS 3 BP 348 EP 349 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809AA UT WOS:000220608400016 ER PT J AU Seinfeld, JH Carmichael, GR Arimoto, R Conant, WC Brechtel, FJ Bates, TS Cahill, TA Clarke, AD Doherty, SJ Flatau, PJ Huebert, BJ Kim, J Markowicz, KM Quinn, PK Russell, LM Russell, PB Shimizu, A Shinozuka, Y Song, CH Tang, YH Uno, I Vogelmann, AM Weber, RJ Woo, JH Zhang, XY AF Seinfeld, JH Carmichael, GR Arimoto, R Conant, WC Brechtel, FJ Bates, TS Cahill, TA Clarke, AD Doherty, SJ Flatau, PJ Huebert, BJ Kim, J Markowicz, KM Quinn, PK Russell, LM Russell, PB Shimizu, A Shinozuka, Y Song, CH Tang, YH Uno, I Vogelmann, AM Weber, RJ Woo, JH Zhang, XY TI ACE-ASIA - Regional climatic and atmospheric chemical effects of Asian dust and pollution SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID CHEJU ISLAND; AEROSOL COMPOSITION; SEASONAL-VARIATION; NORTH PACIFIC; SURFACE; KOREA; BIOMASS; SYSTEM; OXIDES; WATER AB Although continental-scale plumes of Asian dust and pollution reduce the amount of solar radiation reaching the earth's surface and perturb the chemistry of the atmosphere, our ability to quantify these effects has been limited by a lack of critical observations, particularly of layers above the surface. Comprehensive surface, airborne, shipboard, and satellite measurements of Asian aerosol chemical composition, size, optical properties, and radiative impacts were performed during the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) study. Measurements within a massive Chinese dust storm at numerous widely spaced sampling locations revealed the highly complex structure of the atmosphere, in which layers of dust, urban pollution, and biomass-burning smoke may be transported long distances as distinct entities or mixed together. The data allow a first-time assessment of the regional climatic and atmospheric chemical effects of a continental-scale mixture of dust and pollution. Our results show that radiative flux reductions during such episodes are sufficient to cause regional climate change. C1 CALTECH, Dept Chem Engn, Pasadena, CA 91125 USA. CALTECH, Dept Environm Sci & Engn, Pasadena, CA 91125 USA. Univ Iowa, Coll Engn, Iowa City, IA 52242 USA. New Mexico State Univ, CEMRC, Las Cruces, NM 88003 USA. Brechtel Mfg Inc, Hayward, CA USA. NOAA, Pacific Marine & Environm Lab, Seattle, WA 98115 USA. Univ Calif Davis, Dept Chem Engn, Davis, CA 95616 USA. Univ Hawaii Manoa, Dept Oceanog, Honolulu, HI 96822 USA. Univ Washington, Joint Inst Study Atmosphere & Oceans, Seattle, WA 98195 USA. Naval Res Lab, Monterey, CA USA. Meteorol Res Inst KMA, Seoul, South Korea. Warsaw Univ, Inst Geophys, Warsaw, Poland. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Natl Inst Environm Studies, Tsukuba, Ibaraki, Japan. Kyushu Univ, Appl Mech Res Inst, Fukuoka 8168580, Japan. Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. Chinese Acad Sci, Beijing, Peoples R China. RP CALTECH, Dept Chem Engn, Mail Code 210-41, Pasadena, CA 91125 USA. EM seinfeld@caltech.edu RI Uno, Itsushi/B-5952-2011; Shimizu, Atsushi/C-2810-2009; ZHANG, Xiao-Ye/C-8707-2012; Flatau, Piotr/E-2219-2011; Vogelmann, Andrew/M-8779-2014; Doherty, Sarah/D-5592-2015; Kyushu, RIAM/F-4018-2015; U-ID, Kyushu/C-5291-2016; Tang, Youhua/D-5205-2016; Bates, Timothy/L-6080-2016; Quinn, Patricia/R-1493-2016 OI Shimizu, Atsushi/0000-0002-7306-7412; ZHANG, Xiao-Ye/0000-0003-1802-3385; Vogelmann, Andrew/0000-0003-1918-5423; Doherty, Sarah/0000-0002-7796-6968; Tang, Youhua/0000-0001-7089-7915; Quinn, Patricia/0000-0003-0337-4895 NR 38 TC 190 Z9 202 U1 6 U2 34 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 EI 1520-0477 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAR PY 2004 VL 85 IS 3 BP 367 EP + DI 10.1175/BAMS-85-3-367 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809AA UT WOS:000220608400019 ER PT J AU Rodell, M Houser, PR Jambor, U Gottschalck, J Mitchell, K Meng, CJ Arsenault, K Cosgrove, B Radakovich, J Bosilovich, M Entin, JK Walker, JP Lohmann, D Toll, D AF Rodell, M Houser, PR Jambor, U Gottschalck, J Mitchell, K Meng, CJ Arsenault, K Cosgrove, B Radakovich, J Bosilovich, M Entin, JK Walker, JP Lohmann, D Toll, D TI The global land data assimilation system SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID SURFACE SOIL-MOISTURE; CLIMATE MODELS; ETA-MODEL; REAL-TIME; PROJECT; PARAMETERIZATION; PRODUCTS; COVER; IMPLEMENTATION; METHODOLOGY AB A Global Land Data Assimilation System (GLDAS) has been developed. Its purpose is to ingest satellite- and ground-based observational data products, using advanced land surface modeling and data assimilation techniques, in order to generate optimal fields of land surface states and fluxes. GLDAS is unique in that it is an uncoupled land surface modeling system that drives multiple models, integrates a huge quantity of observation-based data, runs globally at high resolution (0.25degrees), and produces results in near-real time (typically within 48 h of the present). GLDAS is also a test bed for innovative modeling and assimilation capabilities. A vegetation-based "tiling" approach is used to simulate subgrid-scale variability, with a 1-km global vegetation dataset as its basis. Soil and elevation parameters are based on high-resolution global datasets. Observation-based precipitation and downward radiation and output fields from the best available global coupled atmospheric data assimilation systems are employed as forcing data. The high-quality, global land surface fields provided by GLDAS will be used to initialize weather and climate prediction models and will promote various hydrometeorological studies and applications. The ongoing GLDAS archive (started in 2001) of modeled and observed, global, surface meteorological data, parameter maps, and output is publicly available. C1 NASA, Hydrol Sci Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Data Assimilat Off, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. NOAA, Natl Ctr Environm Predict, Camp Springs, MD USA. Univ Melbourne, Dept Civil & Environm Engn, Melbourne, Vic, Australia. RP Rodell, M (reprint author), NASA, Hydrol Sci Branch, Goddard Space Flight Ctr, Code 974-1, Greenbelt, MD 20771 USA. EM Matthew.Rodell@nasa.gov RI Rodell, Matthew/E-4946-2012; Bosilovich, Michael/F-8175-2012; Walker, Jeffrey/D-2624-2009; Houser, Paul/J-9515-2013 OI Rodell, Matthew/0000-0003-0106-7437; Houser, Paul/0000-0002-2991-0441 NR 53 TC 1105 Z9 1189 U1 23 U2 162 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 EI 1520-0477 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAR PY 2004 VL 85 IS 3 BP 381 EP + DI 10.1175/BAMS-85-3-381 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809AA UT WOS:000220608400020 ER PT J AU Curry, JA Bentamy, A Bourassa, MA Bourras, D Bradley, EF Brunke, M Castro, S Chou, SH Clayson, CA Emery, WJ Eymard, L Fairall, CW Kubota, M Lin, B Perrie, W Reeder, RA Renfrew, IA Rossow, WB Schulz, J Smith, SR Webster, PJ Wick, GA Zeng, X AF Curry, JA Bentamy, A Bourassa, MA Bourras, D Bradley, EF Brunke, M Castro, S Chou, SH Clayson, CA Emery, WJ Eymard, L Fairall, CW Kubota, M Lin, B Perrie, W Reeder, RA Renfrew, IA Rossow, WB Schulz, J Smith, SR Webster, PJ Wick, GA Zeng, X TI Seaflux SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID SEA-SURFACE TEMPERATURE; LATENT-HEAT FLUX; ATMOSPHERE RESPONSE EXPERIMENT; BULK AERODYNAMIC ALGORITHMS; GENERAL-CIRCULATION MODEL; TROPICAL WESTERN PACIFIC; TURBULENT FLUXES; WIND-SPEED; TOGA COARE; SATELLITE SCATTEROMETER AB High-resolution surface fluxes over the global ocean are needed to evaluate coupled atmosphere-ocean models and weather forecasting models, provide surface forcing for ocean models, understand the regional and temporal variations of the exchange of heat between the atmosphere and ocean, and provide a large-scale context for field experiments. Under the auspices of the World Climate Research Programme (WCRP) Global Energy and Water Cycle Experiment (GEWEX) Radiation Panel, the SEAFLUX Project has been initiated to investigate producing a high-resolution satellite-based dataset of surface turbulent fluxes over the global oceans to complement the existing products for surface radiation fluxes and precipitation. The SEAFLUX Project includes the following elements: a library of in situ data, with collocated satellite data to be used in the evaluation and improvement of global flux products; organized intercomparison projects, to evaluate and improve bulk flux models and determination from the satellite of the input parameters; and coordinated evaluation of the flux products in the context of applications, such as forcing ocean models and evaluation of coupled atmosphere-ocean models. The objective of this paper is to present an overview of the status of global ocean surface flux products, the methodology being used by SEAFLUX, and the prospects for improvement of satellite-derived flux products. C1 Georgia Inst Technol, Dept Earth & Atmospher Sci, Atlanta, GA 30332 USA. IFREMER, Brest, France. Florida State Univ, Ctr Ocean Atmospher Predict Studies, Tallahassee, FL 32306 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. CSIRO Land & Water, Canberra, ACT, Australia. Univ Arizona, Dept Atmospher Sci, Tucson, AZ USA. Univ Colorado, Dept Aerosp Engn Sci, Boulder, CO 80309 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CETP, IPSL, CNRS, Velizy Villacoublay, France. NOAA, ETL, Boulder, CO USA. Tokai Univ, Sch Marine Sci & Technol, Shizuoka, Japan. NASA, Langley Res Ctr, Hampton, VA 23665 USA. Bedford Inst Oceanog, Dartmouth, NS, Canada. British Antarctic Survey, Div Phys Sci, Cambridge CB3 0ET, England. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Univ Bonn, Inst Meteorol, D-5300 Bonn, Germany. RP Georgia Inst Technol, Dept Earth & Atmospher Sci, Atlanta, GA 30332 USA. EM curryja@eas.gatech.edu RI Renfrew, Ian/E-4057-2010; Castro, Sandra/A-4979-2012; Bradley, Frank/I-6574-2013; Rossow, William/F-3138-2015; OI Renfrew, Ian/0000-0001-9379-8215; Emery, William/0000-0002-7598-9082 NR 73 TC 71 Z9 78 U1 2 U2 13 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 EI 1520-0477 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAR PY 2004 VL 85 IS 3 BP 409 EP + DI 10.1175/BAMS-85-3-409 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 809AA UT WOS:000220608400022 ER PT J AU Siebe, C Rodriguez-Lara, V Schaaf, P Abrams, M AF Siebe, C Rodriguez-Lara, V Schaaf, P Abrams, M TI Radiocarbon ages of Holocene Pelado, Guespalapa, and Chichinautzin scoria cones, south of Mexico City: implications for archaeology and future hazards SO BULLETIN OF VOLCANOLOGY LA English DT Article DE Chichinautzin; scoria; radiocarbon; holocene; Trans-Mexican Volcanic Belt; hazards, archaeology ID POPOCATEPETL VOLCANO; CINDER CONES; TIME SCALE; STRATIGRAPHY; CALIBRATION; TETIMPA; VALLEY; HAWAII; FRONT; BELT AB Pelado, Guespalapa, and Chichinautzin monogenetic scoria cones located within the Sierra del Chichinautzin Volcanic Field (SCVF) at the southern margin of Mexico City were dated by the radiocarbon method at 10,000, 2,800-4,700, and 1,835 years B.P., respectively. Most previous research in this area was concentrated on Xitle scoria cone, whose lavas destroyed and buried the pre-Hispanic town of Cuicuilco around 1,665+/-35 years B.P. The new dates indicate that the recurrence interval for monogenetic eruptions in the central part of the SCVF and close to the vicinity of Mexico City is <2,500 years. If the entire SCVF is considered, the recurrence interval is <1,700 years. Based on fieldwork and Landsat imagery interpretation a geologic map was produced, morphometric parameters characterizing the cones and lava flows determined, and the areal extent and volumes of erupted products estimated. The longest lava flow was produced by Guespalapa and reached 24 km from its source; total areas covered by lava flows from each eruption range between 54 (Chichinautzin) and 80 km(2) (Pelado); and total erupted volumes range between 1 and 2 km(3)/cone. An average eruption rate for the entire SCVF was estimated at 0.6 km(3)/1,000 years. These findings are of importance for archaeological as well as volcanic hazards studies in this heavily populated region. C1 Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Siebe, C (reprint author), Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico. EM csiebe@tonatiuh.igeofcu.unam.mx OI Siebe, Claus/0000-0002-3959-9028 NR 55 TC 59 Z9 63 U1 0 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0258-8900 J9 B VOLCANOL JI Bull. Volcanol. PD MAR PY 2004 VL 66 IS 3 BP 203 EP 225 DI 10.1007/s00445-003-0304-z PG 23 WC Geosciences, Multidisciplinary SC Geology GA 806GB UT WOS:000220421300001 ER PT J AU Lawson, PW Logerwell, EA Mantua, NJ Francis, RC Agostini, VN AF Lawson, PW Logerwell, EA Mantua, NJ Francis, RC Agostini, VN TI Environmental factors influencing freshwater survival and smolt production in Pacific Northwest coho salmon (Oncorhynchus kisutch) SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID OREGON PRODUCTION AREA; MARINE SURVIVAL; BRITISH-COLUMBIA; CURRENT VELOCITY; CLIMATE-CHANGE; UNITED-STATES; EL-NINO; TEMPERATURE; STREAM; OCEAN AB Climate variability is well known to affect the marine survival of coho salmon (Oncorhynchus kisutch) in Oregon and Washington. Marine factors have been used to explain up to 83% of the variability in Oregon coastal natural coho salmon recruitment, yet about half the variability in coho salmon recruitment comes from the freshwater life phase of the life cycle. This seeming paradox could be resolved if freshwater variability were linked to climate and climate factors influencing marine survival were correlated with those affecting freshwater survival. Effects of climate on broad-scale fluctuations in freshwater survival or production are not well known. We examined the influence of seasonal stream flows and air temperature on freshwater survival and production of two stock units: Oregon coastal natural coho salmon and Queets River coho salmon from the Washington Coast. Annual air temperatures and second winter flows correlated strongly with smolt production from both stock units. Additional correlates for the Oregon Coast stocks were the date of first fall freshets and flow during smolt outmigration. Air temperature is correlated with sea surface temperature and timing of the spring transition so that good freshwater conditions are typically associated with good marine conditions. C1 Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Newport, OR 97365 USA. Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Seattle, WA 98195 USA. Univ Washington, Sch Marine Affairs, Joint Inst Sci Atmospher & Ocean Climate Impacts, Seattle, WA 98195 USA. Univ Washington, Sch Aquat & Fishery Sci, Seattle, WA 98195 USA. RP Lawson, PW (reprint author), Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, 2032 SE OSU Dr, Newport, OR 97365 USA. EM peter.w.lawson@noaa.gov NR 53 TC 51 Z9 52 U1 0 U2 18 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD MAR PY 2004 VL 61 IS 3 BP 360 EP 373 DI 10.1139/F04-003 PG 14 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 814SC UT WOS:000220993400005 ER PT J AU Kundrot, CE AF Kundrot, CE TI Which strategy for a protein crystallization project? SO CELLULAR AND MOLECULAR LIFE SCIENCES LA English DT Review DE protein crystallization; structural genomics; protein structure; X-ray crystallography; X-ray diffraction ID X-RAY CRYSTALLOGRAPHY; STRUCTURAL GENOMICS; CRYSTAL-STRUCTURE; BINDING-PROTEIN; BIOLOGICAL MACROMOLECULES; ANTIBODY FRAGMENTS; CATALYTIC DOMAIN; LIGHT-SCATTERING; SURFACE RESIDUES; ESCHERICHIA-COLI AB The three-dimensional, atomic-resolution protein structures produced by X-ray crystallography over the past 50+ years have led to tremendous chemical understanding of fundamental biochemical processes. The pace of discovery in protein crystallography has increased greatly with advances in molecular biology, crystallization techniques, cryocrystallography, area detectors, synchrotrons and computing. While the methods used to produce single, well-ordered crystals have also evolved over the years in response to increased understanding and advancing technology, crystallization strategies continue to be rooted in trial-and-error approaches. This review summarizes the current approaches in protein crystallization and surveys the first results to emerge from the structural genomics efforts. C1 NASA, George C Marshall Space Flight Ctr, Micrograv Sci & Applicat Dept, Sci Planning & Program Management Grp, Huntsville, AL 35812 USA. RP Kundrot, CE (reprint author), NASA, George C Marshall Space Flight Ctr, Micrograv Sci & Applicat Dept, Sci Planning & Program Management Grp, Mail Code SD41, Huntsville, AL 35812 USA. EM craig.e.kundrot@nasa.gov NR 90 TC 14 Z9 15 U1 0 U2 8 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 1420-682X J9 CELL MOL LIFE SCI JI Cell. Mol. Life Sci. PD MAR PY 2004 VL 61 IS 5 BP 525 EP 536 DI 10.1007/s00018-003-3260-z PG 12 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 800JT UT WOS:000220025300002 PM 15004692 ER PT J AU Smith, MD Davis-Street, JE Calkins, DS Nillen, JL Smith, SM AF Smith, MD Davis-Street, JE Calkins, DS Nillen, JL Smith, SM TI Stability of i-stat (EC)6+cartridges: Effect of storage temperature on shelf life SO CLINICAL CHEMISTRY LA English DT Letter ID SPACE-FLIGHT C1 NASA, Lyndon B Johnson Space Ctr, Nutr Biochem Lab, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. Enterprise Advisory Serv Inc, Houston, TX USA. Wyle Labs, Houston, TX USA. RP Smith, SM (reprint author), NASA, Lyndon B Johnson Space Ctr, Nutr Biochem Lab, Human Adaptat & Countermeasures Off, Mail Code SK3,2101 NASA Pkwy, Houston, TX 77058 USA. EM scott.m.smith@nasa.gov NR 5 TC 5 Z9 6 U1 0 U2 3 PU AMER ASSOC CLINICAL CHEMISTRY PI WASHINGTON PA 2101 L STREET NW, SUITE 202, WASHINGTON, DC 20037-1526 USA SN 0009-9147 J9 CLIN CHEM JI Clin. Chem. PD MAR PY 2004 VL 50 IS 3 BP 669 EP 673 DI 10.1373/clinchem.2003.028936 PG 5 WC Medical Laboratory Technology SC Medical Laboratory Technology GA 779GT UT WOS:000189287500040 PM 14981042 ER PT J AU Tyuterev, VG Regalia-Jarlot, L Schwenke, DW Tashkun, SA Borkov, YG AF Tyuterev, VG Regalia-Jarlot, L Schwenke, DW Tashkun, SA Borkov, YG TI Global variational calculations of high-resolution rovibrational spectra: isotopic effects, intensity anomalies and experimental confirmations for H2S, HDS, D2S molecules SO COMPTES RENDUS PHYSIQUE LA English DT Article DE variational calculations; spectra; intensity anomalies; isotopic effects ID POTENTIAL-ENERGY SURFACE; BORN-OPPENHEIMER APPROXIMATION; DIPOLE-MOMENT FUNCTION; AB-INITIO; TRIATOMIC-MOLECULES; ABSORPTION-SPECTRUM; HYDROGEN-SULFIDE; WATER; OZONE; SPECTROSCOPY AB Variational calculations of high-resolution infrared molecular spectra for isotopically substituted triatomic molecules from potential and dipole moment functions are discussed. A study of intensity anomalies and of their isotopical behavior especially for symmetry-breaking substitutions represents a particularly interesting subject. Extreme manifestations of intensity anomalies present in spectra of the hydrogen sulfide molecule are considered. A first qualitative experimental confirmation of reported theoretical results for deuterium containing species is discussed. To cite this article: Vl.G. Tyuterev et al., C. R. Physique 5 (2004). (C) 2004 Academie des sciences. Published by Elsevier SAS. All rights reserved. C1 Univ Reims, Fac Sci, GSMA, F-51687 Reims 2, France. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Inst Atmospher Opt, LTS, Tomsk 634055, Russia. RP Tyuterev, VG (reprint author), Univ Reims, Fac Sci, GSMA, Moulin Housse,BP 1039, F-51687 Reims 2, France. EM vladimir.tyuterev@univ-reims.fr RI Tashkun, Sergey/E-8682-2014; schwenke, david/I-3564-2013; Borkov, Yury/R-9124-2016 OI Borkov, Yury/0000-0002-6575-9881 NR 40 TC 20 Z9 22 U1 0 U2 8 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS PA 23 RUE LINOIS, 75724 PARIS, FRANCE SN 1631-0705 J9 CR PHYS JI C. R. Phys. PD MAR PY 2004 VL 5 IS 2 BP 189 EP 199 DI 10.1016/j.crhy.2004.01.017 PG 11 WC Astronomy & Astrophysics; Physics, Multidisciplinary SC Astronomy & Astrophysics; Physics GA 831VJ UT WOS:000222224200004 ER PT J AU Arnold, SM Bednarcyk, BA Aboudi, J AF Arnold, SM Bednarcyk, BA Aboudi, J TI Analysis of internally cooled structures using a higher order theory SO COMPUTERS & STRUCTURES LA English DT Article DE thermal analysis; deformation; elasticity; ceramics; parametric study ID FUNCTIONALLY GRADED MATERIALS AB This paper presents the results of a study on the thermo-mechanical behavior of internally cooled silicon nitride structures. Silicon nitride is tinder consideration for elevated temperature aerospace engine applications, and techniques for lowering the operating temperature of structures composed of this material are under development. Lowering the operating temperature provides a large payoff in terms of fatigue life and may be accomplished through the use of thermal barrier coatings (TBCs) and the novel concept of included cooling channels. Herein, an in depth study is performed on the behavior of a flame-impinged silicon nitride plate with a TBC and internal channels cooled by forced air. The analysis is performed using the higher order theory for functionally graded materials (HOTFGM), which has been developed through NASA Glenn Research Center funding over the past several years. HOTFGM was chosen over the traditional finite element approach in order to facilitate examination of functionally graded silicon nitride structures for which HOTFGM is ideally suited. To accommodate the analysis requirements of the internally cooled plate problem, two crucial enhancements were made to the two-dimensional Cartesian-based version of HOTFGM, namely, incorporation of internal boundary capabilities and incorporation of convective boundary conditions. Results indicate the viability and large benefits of cooling the plate via forced air through cooling channels. Furthermore, cooling can positively impact the stress and displacement fields present in the plate, yielding an additional payoff in terms of fatigue life. Results illustrating the benefits associated with particular cooling channel arrangements and functionally grading the silicon nitride material are also presented. Finally, a spin off capability resulted from inclusion of internal boundaries within HOTFGM; the ability to simulate the thermo-elastic response of structures with curved surfaces. This new capability is demonstrated, and through comparison with an analytical solution, shown to be viable and accurate. (C) 2004 Published by Elsevier Ltd. C1 NASA, Glenn Res Ctr Lewis Field, Life Predict Branch, Cleveland, OH 44135 USA. Ohio Aerosp Inst, Cleveland, OH 44142 USA. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. RP Arnold, SM (reprint author), NASA, Glenn Res Ctr Lewis Field, Life Predict Branch, 21000 Brookpk Rd,Mail Stop 49-7, Cleveland, OH 44135 USA. EM s.arnold@grc.nasa.gov NR 15 TC 7 Z9 7 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-7949 J9 COMPUT STRUCT JI Comput. Struct. PD MAR PY 2004 VL 82 IS 7-8 BP 659 EP 688 DI 10.1016/j.compstruc.2003.11.004 PG 30 WC Computer Science, Interdisciplinary Applications; Engineering, Civil SC Computer Science; Engineering GA 810BF UT WOS:000220679100010 ER PT J AU Gharrett, AJ Keller, S Gustafson, RG Johnson, P Nielsen, JL Seeb, JE Seeb, LW Smoker, WW Thorgaard, GH Wilmot, RL AF Gharrett, AJ Keller, S Gustafson, RG Johnson, P Nielsen, JL Seeb, JE Seeb, LW Smoker, WW Thorgaard, GH Wilmot, RL TI Introduction to genetics of subpolar fish and invertebrates SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Editorial Material DE quantitative genetics; population genetics; molecular genetics; aquaculture; systematics; wild-hatchery interactions C1 Univ Alaska Fairbanks, Sch Fisheries & Ocean Sci, Div Fisheries, Juneau, AK 99801 USA. Univ Alaska Fairbanks, Sch Fisheries & Ocean Sci, Alaska Sea Grant Coll Program, Fairbanks, AK 99775 USA. Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Conservat Biol Div, Seattle, WA 98112 USA. Natl Marine Fisheries Serv, Auke Bay Lab, Alaska Fisheries Sci Ctr, Juneau, AK 99801 USA. US Geol Survey, Alaska Sci Ctr, Anchorage, AK 99503 USA. Alaska Dept Fish & Game, Commercial Fisheries Div, Anchorage, AK 99518 USA. Washington State Univ, Sch Biol Sci, Pullman, WA 99164 USA. Washington State Univ, Ctr Reprod Biol, Pullman, WA 99164 USA. RP Gharrett, AJ (reprint author), Univ Alaska Fairbanks, Sch Fisheries & Ocean Sci, Div Fisheries, 11120 Glacier Highway, Juneau, AK 99801 USA. EM ffajg@uaf.edu NR 40 TC 1 Z9 1 U1 2 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD MAR PY 2004 VL 69 IS 1-4 BP 1 EP 5 DI 10.1023/B:EBFI.0000022978.62262.47 PG 5 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 809YJ UT WOS:000220671700001 ER PT J AU Seeb, LW Crane, PA Kondzela, CM Wilmot, RL Urawa, S Varnavskaya, NV Seeb, JE AF Seeb, LW Crane, PA Kondzela, CM Wilmot, RL Urawa, S Varnavskaya, NV Seeb, JE TI Migration of Pacific Rim chum salmon on the high seas: insights from genetic data SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article; Proceedings Paper CT 20th Lowell Wakefield Fisheries Symposium CY MAY 29-31, 2002 CL Univ Alaska Sea, Juneau, AK HO Univ Alaska Sea DE Oncorhynchus keta; mixed stock analyses; allozyme electrophoresis ID STOCK IDENTIFICATION; WESTERN ALASKA; POPULATIONS; DIVERSITY; NORTHERN AB Wild stocks of chum salmon, Oncorhynchus keta, have experienced recent declines in some areas of their range. Also, the release of hatchery chum salmon has escalated to nearly three billion fish annually. The decline of wild stocks and the unknown effects of hatchery fish combined with the uncertainty of future production caused by global climate change have renewed interest in the migratory patterns of chum salmon on the high seas. We studied the composition of high-seas mixtures of maturing and immature individuals using baseline data for 20 allozyme loci from 356 populations from throughout the Pacific Rim. Composition estimates were made from three time series. Two of these time series were from important coastal migratory corridors: the Shumagin Islands south of the Alaska Peninsula and the east coast of the Kamchatka Peninsula. The third was from chum salmon captured incidentally in the Bering Sea trawl fishery for walleye pollock. We also analyzed geographically dispersed collections of chum salmon captured in the month of July. The time series show dynamic changes in stock composition. The Shumagin Island corridor was used primarily by Northwest Alaskan and Asian populations in June; by the end of July stocks from the Alaska Peninsula and southern North America dominated the composition. The composition along the Kamchatka coast changed dramatically from primarily Russian stocks in May to primarily Japanese stocks in August; the previously undocumented presence of stocks from the Alaska Peninsula and Gulf of Alaska was also demonstrated. Immature chum salmon from throughout the Pacific Rim, including large proportions of southern North American stocks, contributed to the Bering Sea bycatch during the months of September and October. The migration routes of North American stocks is far more widespread than previously observed, and the Bering Sea is an important rearing area for maturing and immature chum salmon from throughout the species' range. C1 Alaska Dept Fish & Game, Gene Conservat Lab, Anchorage, AK 99518 USA. Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. Fisheries Agcy Japan, Natl Salmon Resources Ctr, Toyohira Ku, Sapporo, Hokkaido 0620922, Japan. Kamchatka Res Inst Fisheries & Oceanog, Petropavlovsk Kamchatski 683600, Russia. RP Seeb, LW (reprint author), Alaska Dept Fish & Game, Gene Conservat Lab, 333 Raspberry Rd, Anchorage, AK 99518 USA. EM lisa_seeb@fishgame.state.ak.us NR 29 TC 40 Z9 47 U1 2 U2 8 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD MAR PY 2004 VL 69 IS 1-4 BP 21 EP 36 DI 10.1023/B:EBFI.0000022900.82523.63 PG 16 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 809YJ UT WOS:000220671700003 ER PT J AU Thrower, F Guthrie, C Nielsen, J Joyce, J AF Thrower, F Guthrie, C Nielsen, J Joyce, J TI A comparison of genetic variation between an anadromous steelhead, Oncorhynchus mykiss, population and seven derived populations sequestered in freshwater for 70 years SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article; Proceedings Paper CT 20th Lowell Wakefield Fisheries Symposium CY MAY 29-31, 2002 CL Univ Alaska Sea, Juneau, AK HO Univ Alaska Sea DE rainbow trout; DNA; microsatellites; allozymes ID FISH; MITOCHONDRIAL; HATCHERY; SALMON; STOCK AB In 1926 cannery workers from the Wakefield Fisheries Plant at Little Port Walter in Southeast Alaska captured small trout, Oncorhynchus mykiss, from a portion of Sashin Creek populated with a wild steelhead (anadromous O. mykiss) run. They planted them into Sashin Lake which had been fishless to that time and separated from the lower stream by two large waterfalls that prevented upstream migration of any fish. In 1996 we sampled adult steelhead from the lower creek and juvenile O. mykiss from an intermediate portion of the creek, Sashin Lake, and five lakes that had been stocked with fish from Sashin Lake in 1938. Tissue samples from these eight populations were compared for variation in: microsatellite DNA at 10 loci; D-loop sequences in mitochondrial DNA; and allozymes at 73 loci known to be variable in steelhead. Genetic variability was consistently less in the Sashin Lake population and all derived populations than in the source anadromous population. The cause of this reduction is unknown but it is likely that very few fish survived to reproduce from the initial transplant in 1926. Stockings of 50 - 85 fish into five other fishless lakes in 1938 from Sashin Lake did not result in a similar dramatic reduction in variability. We discuss potential explanations for the observed patterns of genetic diversity in relation to the maintenance of endangered anadromous O. mykiss populations in freshwater refugia. C1 Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. USGS, Alaska Sci Ctr, Off Biol Sci, Anchorage, AK USA. RP Thrower, F (reprint author), Natl Marine Fisheries Serv, Auke Bay Lab, 11305 Glacier Hwy, Juneau, AK 99801 USA. EM frank.thrower@noaa.gov NR 16 TC 32 Z9 32 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD MAR PY 2004 VL 69 IS 1-4 BP 111 EP 125 DI 10.1023/B:EBFI.0000022880.52256.92 PG 15 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 809YJ UT WOS:000220671700009 ER PT J AU Matala, AP Gray, AK Heifetz, J Gharrett, AJ AF Matala, AP Gray, AK Heifetz, J Gharrett, AJ TI Population structure of Alaskan shortraker rockfish, Sebastes borealis, inferred from microsatellite variation SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article; Proceedings Paper CT 20th Lowell Wakefield Fisheries Symposium CY MAY 29-31, 2002 CL Univ Alaska Sea, Juneau, AK HO Univ Alaska Sea DE population genetics; marine fisheries; Wakefield Symposium ID GENUS SEBASTES; JUVENILES; ECOLOGY; LARVAE; FLOW AB Alaskan shortraker rockfish population structure was analyzed by examining allelic variation at eight microsatellite loci. Samples were collected along the continental shelf and upper slope from the south end of Baranof Island to the western Aleutian Islands, and collections were pooled into eight geographically distinct groups. An exact test of homogeneity indicated population structure ( p < 0.0006) among groups. The proportion of the total variation that was attributable to divergence among populations (θ = 0.0014) was not statistically significant, and no evidence of a geographic cline of structure was detected. Finer scale analyses that compared adjacent collections indicated that the collection from the southern end of the range differed from all remaining collections at three loci. Structure related to geographic location was detected by partitioning the variation among populations. The size distributions of shortraker rockfish varied among collections from east to west. The size differences may reflect divergent oceanographic and biological factors acting on populations that have restricted migration and movement. Alternatively, if there is substantial movement accompanied by lengthy reverse migration to natal grounds, the size differences may be related to ages of cohorts that are differentially distributed along the Pacific Rim. Further biological information including size, age composition, and age of maturity data, as well as information on other life history characteristics will be required to explain shortraker rockfish population structure. C1 Univ Alaska, Sch Fisheries & Ocean Sci, Div Fisheries, Juneau, AK 99801 USA. Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. RP Matala, AP (reprint author), Univ Alaska, Sch Fisheries & Ocean Sci, Div Fisheries, 11120 Glacier Highway, Juneau, AK 99801 USA. EM ffajg@uaf.edu NR 34 TC 15 Z9 15 U1 0 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD MAR PY 2004 VL 69 IS 1-4 BP 201 EP 210 DI 10.1023/B:EBFI.0000022876.71349.be PG 10 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 809YJ UT WOS:000220671700016 ER PT J AU Gilk, SE Wang, IA Hoover, CL Smoker, WW Taylor, SG Gray, AK Gharrett, AJ AF Gilk, SE Wang, IA Hoover, CL Smoker, WW Taylor, SG Gray, AK Gharrett, AJ TI Outbreeding depression in hybrids between spatially separated pink salmon, Oncorhynchus gorbuscha, populations: marine survival, homing ability, and variability in family size SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article; Proceedings Paper CT 20th Lowell Wakefield Fisheries Symposium CY MAY 29-31, 2002 CL Univ Alaska Sea, Juneau, AK HO Univ Alaska Sea DE conservation biology; local adaptation; microsatellites; salmonid ID COHO SALMON; MICROSATELLITE LOCI; GENETIC-VARIABILITY; PACIFIC SALMON; CHINOOK SALMON; RAINBOW-TROUT; EVEN-YEAR; KISUTCH; FISH; WILD AB Hybridization between distinct populations and introgression of nonnative genes can erode fitness of native populations through outbreeding depression, either by producing a phenotype intermediate to that of both contributing genomes (and maladapted in either population's environment) or by disrupting distinct coadapted complexes of epistatic genes. In salmon, fitness-related traits such as homing ability or family-size distribution may be eroded. We investigated geographically separated pink salmon populations in repeated trials in independent broodyears (odd and even). Hybrids were made between female Auke Creek (Southeast Alaska) pink salmon and Pillar Creek (Kodiak Island, similar to1000 km away) males; hybrids and their offspring were compared to offspring of control crosses of the same females with Auke Creek males. Parentage assignment from microsatellite analysis was used to improve estimates of survival and straying and to examine variation of family size. Hybridization reduced return rates of adults (a proxy for survival at sea) in the F-1 generation in the odd-year broodline (p < 0.0001) but not in the even-year broodline (p = 0.678). Hybridization reduced survival in both the odd- and even-broodyear F-2 (p < 0.005 and p < 0.0001). Hybridization did not appear to impair homing ability; weekly surveys revealed similar straying rates (&SIM;2%) by both hybrid and control fish into nearby (&SIM;1 km) Waydelich Creek in both generations in both trials. Hybridization did not increase the index of variability (σ(2)/μ) in family size. Decreased survival in the hybrid F-2 generation supports an epistatic model of outbreeding depression; nonepistatic effects may have contributed to reduced survival in the odd-broodyear F-1 hybrid fish. Outbreeding depression in hybrids of geographically separated populations demonstrates that introgression of nonnative fish can erode fitness, and should be recognized as a potential detriment of both aquaculture and management practices. C1 Univ Alaska, Sch Fisheries & Ocean Sci, Div Fisheries, Juneau, AK 99801 USA. Natl Marine Fisheries Serv, NOAA, Alaska Fisheries Sci Ctr, Auke Bay Lab, Juneau, AK 99801 USA. RP Gharrett, AJ (reprint author), Univ Alaska, Sch Fisheries & Ocean Sci, Div Fisheries, 11120 Glacier Highway, Juneau, AK 99801 USA. EM ffajg@uaf.edu NR 55 TC 74 Z9 75 U1 2 U2 36 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD MAR PY 2004 VL 69 IS 1-4 BP 287 EP 297 DI 10.1023/B:EBFI.0000022888.28218.c1 PG 11 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 809YJ UT WOS:000220671700023 ER PT J AU Michaut, C Stehle, C Leygnac, S Lanz, T Boireau, L AF Michaut, C Stehle, C Leygnac, S Lanz, T Boireau, L TI Jump conditions in hypersonic shocks - Quantitative effects of ionic excitation and radiation SO EUROPEAN PHYSICAL JOURNAL D LA English DT Article ID LASER-PRODUCED PLASMAS; IONIZATION AB We study the quantitative effects of excitation, ionization, radiation energy and pressure, oil the jump conditions in hypersonic shocks in a real gas. The ionization structure and excitation energies are calculated from file local temperature and density, rising the Screened Hydrogenic Model. We assume an optically thick medium and no radiation flux through the shock front. We investigate the jump conditions in different gases and propose a phenomenological description of compression for different shock velocities. We find that the excitation energy term is the dominant term in ionized gases at low velocities. Consequently, higher shock velocities than the values predicted by standard calculations in a perfect gas must be reached in order to observe the effects of radiation in the compression ratio. Our results provide constraints for the design of future radiative shock experiments oil the next generation of powerful nanosecond lasers or oil Z-pinches. C1 Observ Paris, LUTH, CNRS, UMR 8102, F-92195 Meudon, France. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Michaut, C (reprint author), Observ Paris, LUTH, CNRS, UMR 8102, 5 Pl J Janssen, F-92195 Meudon, France. EM Claire.Michaut@obspm.fr NR 26 TC 34 Z9 34 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6060 J9 EUR PHYS J D JI Eur. Phys. J. D PD MAR PY 2004 VL 28 IS 3 BP 381 EP 392 DI 10.1140/epjd/e2003-00322-3 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 805PO UT WOS:000220378400009 ER PT J AU Swimmer, Y McNaughton, L Moyes, C Brill, R AF Swimmer, Y McNaughton, L Moyes, C Brill, R TI Metabolic biochemistry of cardiac muscle in three tuna species (bigeye, Thunnus obesus; yellowfin, T-albacares; and skipjack, Katsuwonus pelamis) with divergent ambient temperature and oxygen tolerances SO FISH PHYSIOLOGY AND BIOCHEMISTRY LA English DT Article DE enzymes; heart; Scombridae ID MYSID GNATHOPHAUSIA-INGENS; SATELLITE ARCHIVAL TAGS; BLUEFIN TUNA; MINIMUM LAYER; LACTATE-DEHYDROGENASES; ULTRASONIC TELEMETRY; VERTICAL MOVEMENTS; HAWAIIAN-ISLANDS; HEARTS; PACIFIC AB Bigeye tuna (Thunnus obesus) have much greater vertical mobility than yellowfin (T. albacares) and skipjack (Katsuwonus pelamis) tunas, due to an apparent greater tolerance of the changes in ambient temperature and oxygen occurring with depth. In an attempt to identify physiological processes (e.g., effects of temperature on cardiac function) responsible for these behavioral differences, we examined enzyme activities (at 12&DEG; C, 17&DEG; C, and 25&DEG; C) of cardiac muscle in all three species. Contrary to our expectations, we found few differences and no clear explanatory patterns in maximum enzyme activities (V-max) or enzyme activity ratios. For example, citrate synthase (CS) activity was the same in bigeye and skipjack tunas, but = 40% lower in yellowfin tuna, whereas carnitine palmotoyltransferase (CPT) activity in skipjack tuna was approximately double that in the other two species. The ratio of CPT to pyruvate kinase (PK) activity, a measure of the tissues' preference for fatty acids as metabolic substrates, was the same in bigeye and yellowfin tunas, but elevated skipjack tuna. The ratios of lactate dehydrogenase (LDH) to CS activity and of PK to CS activity (anaerobic-aerobic enzyme activity ratios - taken as measures of the tissues' ability to tolerate hypoxia) were both elevated in yellowfin tuna cardiac tissue relative to the other two species. We also found no differences in temperature sensitivity (Q(10) values) when comparing cardiac enzyme activities across species, nor effects of temperature on the substrate affinity (K-m) of LDH. In sum, our results do not suggest any clear metabolic difference in the cardiac muscle that would explain the apparent greater tolerance of bigeye tuna to acute hypoxia and ambient temperature changes or their substantially greater vertical mobility. C1 Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Joint Inst Marine & Atmospher Res, Pelag Fisheries Res Program, Honolulu, HI 96822 USA. Queens Univ, Dept Biol, Kingston, ON K7L 3N6, Canada. NOAA, Natl Marine Fisheries Serv, Honolulu Lab, Honolulu, HI 96822 USA. RP Swimmer, Y (reprint author), Virginia Inst Marine Sci, POB 1346, Gloucester Point, VA 23062 USA. EM rbrill@vims.edu NR 52 TC 6 Z9 7 U1 1 U2 37 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0920-1742 J9 FISH PHYSIOL BIOCHEM JI Fish Physiol. Biochem. PD MAR PY 2004 VL 30 IS 1 BP 27 EP 35 DI 10.1007/s10695-004-5465-y PG 9 WC Biochemistry & Molecular Biology; Fisheries; Physiology SC Biochemistry & Molecular Biology; Fisheries; Physiology GA 922YB UT WOS:000228874700004 ER PT J AU Havelund, K Rosu, G AF Havelund, K Rosu, G TI Special issue on selected papers from the First International Workshop on Runtime Verification held in Paris, July 2001 (RV'01) - Foreword SO FORMAL METHODS IN SYSTEM DESIGN LA English DT Editorial Material C1 NASA, Ames Res Ctr, Kestrel Technol, Moffett Field, CA 94035 USA. Univ Illinois, Urbana, IL 61801 USA. RP Havelund, K (reprint author), NASA, Ames Res Ctr, Kestrel Technol, Moffett Field, CA 94035 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0925-9856 J9 FORM METHOD SYST DES JI Form. Methods Syst. Des. PD MAR PY 2004 VL 24 IS 2 BP 99 EP 100 DI 10.1023/B:FORM.0000017842.17301.bc PG 2 WC Computer Science, Theory & Methods SC Computer Science GA 778KA UT WOS:000189239700001 ER PT J AU Havelund, K Rosu, G AF Havelund, K Rosu, G TI An overview of the runtime verification tool Java PathExplorer SO FORMAL METHODS IN SYSTEM DESIGN LA English DT Article; Proceedings Paper CT 1st International Workshop on Runtime Verification CY JUL, 2001 CL Paris, FRANCE DE runtime verification; trace analysis; temporal logic; rewriting logic; Maude; automata; dynamic programming; program instrumentation; deadlocks; data races; Java ID MODEL-CHECKING; PROGRAMS/ AB We present an overview of the Java PathExplorer runtime verification tool, in short referred to as JPAX. JPAX can monitor the execution of a Java program and check that it conforms with a set of user provided properties formulated in temporal logic. JPAX can in addition analyze the program for concurrency errors such as deadlocks and data races. The concurrency analysis requires no user provided specification. The tool facilitates automated instrumentation of a program's bytecode, which when executed will emit an event stream, the execution trace, to an observer. The observer dispatches the incoming event stream to a set of observer processes, each performing a specialized analysis, such as the temporal logic verification, the deadlock analysis and the data race analysis. Temporal logic specifications can be formulated by the user in the Maude rewriting logic, where Maude is a high-speed rewriting system for equational logic, but here extended with executable temporal logic. The Maude rewriting engine is then activated as an event driven monitoring process. Alternatively, temporal specifications can be translated into automata or algorithms that can efficiently check the event stream. JPAX can be used during program testing to gain increased information about program executions, and can potentially furthermore be applied during operation to survey safety critical systems. C1 NASA, Ames Res Ctr, Kestrel Technol, Moffett Field, CA 94035 USA. Univ Illinois, Dept Comp Sci, Urbana, IL 61801 USA. RP NASA, Ames Res Ctr, Kestrel Technol, Moffett Field, CA 94035 USA. EM havelund@email.arc.nasa.gov; grosu@cs.uiuc.edu NR 41 TC 67 Z9 69 U1 0 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0925-9856 EI 1572-8102 J9 FORM METHOD SYST DES JI Form. Methods Syst. Des. PD MAR PY 2004 VL 24 IS 2 BP 189 EP 215 DI 10.1023/B:FORM.0000017721.39909.4b PG 27 WC Computer Science, Theory & Methods SC Computer Science GA 778KA UT WOS:000189239700005 ER PT J AU Paik, HJ Moody, MV Strayer, DM AF Paik, HJ Moody, MV Strayer, DM TI Short-range inverse-square law experiment in space SO GENERAL RELATIVITY AND GRAVITATION LA English DT Article DE inverse-square law; superconducting differential accelerometer ID SUPERCONDUCTING GRAVITY GRADIOMETER; DIMENSIONS; FORCES AB The objective of ISLES (Inverse-Square Law Experiment in Space) is to perform a null test of Newton's law in space with a resolution of one part in 10(5) or better at 100 mum. ISLES will be sensitive enough to detect axions with the strongest allowed coupling and probe large extra dimensions of string theory down to a few mum. The experiment will be cooled to less than or equal to2 K, which permits superconducting magnetic levitation of the test masses. This soft, low-loss suspension, combined with a low-noise SQUID, leads to extremely low intrinsic noise in the detector. To minimize Newtonian errors, ISLES employs a near null source, a circular disk of large diameter-to-thickness ratio. Two test masses, also disk-shaped, are suspended on the two sides of the source mass at a nominal distance of 100 mum. The signal is detected by a superconducting differential accelerometer. C1 Univ Maryland, Dept Phys, College Pk, MD 20742 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Paik, HJ (reprint author), Univ Maryland, Dept Phys, College Pk, MD 20742 USA. NR 19 TC 5 Z9 5 U1 0 U2 2 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0001-7701 J9 GEN RELAT GRAVIT JI Gen. Relativ. Gravit. PD MAR PY 2004 VL 36 IS 3 BP 523 EP 537 DI 10.1023/B:GERG.0000010728.51445.51 PG 15 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 760YN UT WOS:000187863000004 ER PT J AU Lammerzahl, C Ahlers, G Ashby, N Barmatz, M Biermann, PL Dittus, H Dohm, V Duncan, R Gibble, K Lipa, J Lockerbie, N Mulders, N Salomon, C AF Lammerzahl, C Ahlers, G Ashby, N Barmatz, M Biermann, PL Dittus, H Dohm, V Duncan, R Gibble, K Lipa, J Lockerbie, N Mulders, N Salomon, C TI Experiments in fundamental physics scheduled and in development for the ISS SO GENERAL RELATIVITY AND GRAVITATION LA English DT Review DE ISS; microgravity; Special Relativity; General Relativity; speed of light; gravitational red shift; renormalization group-theory; liquid Helium; high energy cosmic rays ID RENORMALIZATION-GROUP THEORY; ENERGY COSMIC-RAYS; SELF-ORGANIZED CRITICALITY; NONLINEAR HEAT-TRANSPORT; SUPERFLUID TRANSITION; LAMBDA-TRANSITION; ATOMIC FOUNTAIN; FREQUENCY-SHIFT; HE-4; SPACE AB This is a review of those experiments in the area of Fundamental Physics that are either approved by ESA and NASA, or are currently under development, which are to be performed in the microgravity environment of the International Space Station. These experiments cover the physics of liquid Helium ( SUE, BEST, MISTE, DYNAMX, and EXACT), ultrastable atomic clocks (PHARAO, PARCS, RACE), ultrastable microwave resonators (SUMO), and particle detectors (AMS and EUSO). The scientific goals are to study more precisely the universality properties of liquid Helium under microgravity conditions, to establish better time standards and to test the universality of the gravitational red shift, to make more precise tests of the constancy of the speed of light, and to measure the particle content in space directly without disturbances from the Earth's inner atmosphere. C1 Univ Bremen, Ctr Appl Space Technol & Micrograv ZARM, D-28359 Bremen, Germany. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, iQUEST, Santa Barbara, CA 93106 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Max Planck Inst Radio Astron, D-53121 Bonn, Germany. Univ Aachen, Inst Theoret Phys, D-52056 Aachen, Germany. Univ New Mexico, Albuquerque, NM 87131 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Univ Strathclyde, Dept Phys & Appl Phys, Glasgow G4 ONG, Lanark, Scotland. Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA. Ecole Normale Super, Dept Phys, Lab Kastler Brossel, F-75231 Paris, France. RP Lammerzahl, C (reprint author), Univ Bremen, Ctr Appl Space Technol & Micrograv ZARM, D-28359 Bremen, Germany. NR 44 TC 23 Z9 27 U1 2 U2 12 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0001-7701 J9 GEN RELAT GRAVIT JI Gen. Relativ. Gravit. PD MAR PY 2004 VL 36 IS 3 BP 615 EP 649 DI 10.1023/B:GERG.0000010734.62571.b4 PG 35 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 760YN UT WOS:000187863000010 ER PT J AU Schulte, MD Rogers, KL AF Schulte, MD Rogers, KL TI Thiols in hydrothermal solution: standard partial molal properties and their role in the organic geochemistry of hydrothermal environments SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID THERMODYNAMIC PROPERTIES; HIGH-PRESSURES; TRANSPORT-PROPERTIES; AMINO-ACIDS; METASTABLE EQUILIBRIUM; DISSOCIATION-CONSTANTS; HIGH-TEMPERATURES; SULFUR-COMPOUNDS; HEAT-CAPACITIES; IRON SULFIDE AB In order to assess the potential role of organic sulfur compounds in hydrothermal systems, we use recent advances in theoretical geochemistry to estimate the standard partial molal thermodynamic properties and parameters for the revised Helgeson-Kirkham-Flowers equation of state for aqueous straight-chain alkyl thiols. Thermodynamic properties are used to determine the potential for thiol formation in both modern and Archean hydrothermal systems. We conclude that organic sulfur compounds may hold the key to the organic chemistry that led to the origin of life in hydrothermal settings. These results may also explain the presence of sulfur in a number of biomolecules present in ancient thermophilic microorganisms. Copyright (C) 2004 Elsevier Ltd. C1 NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. RP Schulte, MD (reprint author), NASA, Ames Res Ctr, Exobiol Branch, Mail Stop 239-4, Moffett Field, CA 94035 USA. EM mschulte@mail.arc.nasa.gov RI Rogers, Karyn/K-7670-2015 NR 55 TC 36 Z9 36 U1 0 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD MAR PY 2004 VL 68 IS 5 BP 1087 EP 1097 DI 10.1016/j.gca.2003.06.001 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 774WP UT WOS:000189009600011 ER PT J AU Privette, JL Tian, Y Roberts, G Scholes, RJ Wang, Y Caylor, KK Frost, P Mukelabai, M AF Privette, JL Tian, Y Roberts, G Scholes, RJ Wang, Y Caylor, KK Frost, P Mukelabai, M TI Vegetation structure characteristics and relationships of Kalahari woodlands and savannas SO GLOBAL CHANGE BIOLOGY LA English DT Article DE clumping; Kalahari; leaf area index; SAFARI 2000; savanna; scaling; semi-arid; vegetation structure ID INITIATIVE SAFARI 2000; LEAF-AREA INDEX; MODIS-LAI PRODUCT; SOUTHERN-AFRICA; VALIDATION AB The Kalahari Transect is one of several International Geosphere-Biosphere Programme (IGBP) transects designed to address global change questions at the regional scale, in particular by exploiting natural parameter gradients ( Koch et al., 1995 ). In March 2000, we collected near-synoptic vegetation structural data at five sites spanning the Kalahari's large precipitation gradient (about 300-1000 mm yr(-1)) from southern Botswana (similar to24degreesS) to Zambia (similar to15degreesS). All sites were within the expansive Kalahari sandsheet. Common parameters, including plant area index (PAI), leaf area index (LAI) and canopy cover (CC), were measured or derived using several indirect instruments and at multiple spatial scales. Results show that CC and PAI increase with increasing mean annual precipitation. Canopy clumping, defined by the deviation of the gap size distribution from that of randomly distributed foliage, was fairly constant along the gradient. We provide empirical relationships relating these parameters to each other and to precipitation. These results, combined with those in companion Kalahari Transect studies, provide a unique and coherent test bed for ecological modeling. The data may be used to parameterize process models, as well as test internally predicted parameters and their variability in response to well-characterized climatological differences. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Georgia Inst Technol, Sch Atmospher Sci, Atlanta, GA 30332 USA. UCL, Dept Geog, London WC1E 6BT, England. CSIR Environmentek, Pretoria, South Africa. Princeton Univ, Dept Hydrol, Princeton, NJ 08544 USA. Univ Zimbabwe, Inst Environm Studies, Harare, Zimbabwe. Zambian Meteorol Serv, Mongu, Zambia. RP Privette, JL (reprint author), NASA, Goddard Space Flight Ctr, Code 923, Greenbelt, MD 20771 USA. EM jeff.privette@nasa.gov RI Caylor, Kelly/B-7734-2008; Privette, Jeffrey/G-7807-2011; OI Caylor, Kelly/0000-0002-6466-6448; Privette, Jeffrey/0000-0001-8267-9894; Scholes, Robert/0000-0001-5537-6935 NR 27 TC 34 Z9 35 U1 0 U2 15 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1354-1013 J9 GLOBAL CHANGE BIOL JI Glob. Change Biol. PD MAR PY 2004 VL 10 IS 3 BP 281 EP 291 DI 10.1111/j.1529-8817.2003.00740.x PG 11 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 776WC UT WOS:000189141500002 ER PT J AU Roush, TL Dalton, JB AF Roush, TL Dalton, JB TI Reflectance spectra of hydrated Titan tholins at cryogenic temperatures and implications for compositional interpretation of red objects in the outer Solar System SO ICARUS LA English DT Article DE low-temperature reflectance spectra; Titan tholins; solid organic residues; outer Solar System; compositional interpretation ID OPTICAL-CONSTANTS; 5145 PHOLUS; ASTEROIDS; MINERALS; SURFACE; METEORITES; EVOLUTION; IAPETUS AB We report the visible and near-infrared (0.4-2.5 mum) laboratory bidirectional reflectance of hydrated Titan tholin at cryogenic temperatures (similar to 100-300 K). When compared with room temperature measurements, the visible and near-infrared color of hydrated Titan tholin becomes bluer by similar to 14% at low temperatures in the 0.7-1.0 mum region. Assuming the observed color changes are representative of tholin-like materials we estimate the influence of such color changes on the interpretation of the Centaur Pholus and find that the modest color changes will not significantly alter existing interpretations. Published by Elsevier Inc. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. SETI Inst, Mountain View, CA 94043 USA. RP Roush, TL (reprint author), NASA, Ames Res Ctr, MS 245-3, Moffett Field, CA 94035 USA. EM troush@mail.arc.nasa.gov NR 27 TC 11 Z9 11 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAR PY 2004 VL 168 IS 1 BP 158 EP 162 DI 10.1016/j.icarus.2003.11.001 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 802KC UT WOS:000220161400014 ER PT J AU Dello Russo, N DiSanti, MA Magee-Sauer, K Gibb, EL Mumma, MJ Barber, RJ Tennyson, J AF Dello Russo, N DiSanti, MA Magee-Sauer, K Gibb, EL Mumma, MJ Barber, RJ Tennyson, J TI Water production and release in Comet 153P/Ikeya-Zhang (C/2002 C1): accurate rotational temperature retrievals from hot-band lines near 2.9-mu m SO ICARUS LA English DT Article DE Comets; Ikeya-Zhang; infrared; spectroscopy; water ID O1 HALE-BOPP; C/1996 B2 HYAKUTAKE; CARBON-MONOXIDE; INFRARED-SPECTROSCOPY; HYDROGEN-CYANIDE; EMISSION FEATURE; WILSON 19861; SPECTRUM; ETHANE; FLUORESCENCE AB Multiple non-resonance fluorescence lines of water (H2O) were detected in Comet 153/P Ikeya-Zhang (2002 C1) between UT 2002 March 21.9 (R-h = 0.51 AU) and April 13.9 (R-h = 0.78 AU), using the Cryogenic Echelle Spectrometer (CSHELL) at the NASA Infrared Telescope Facility. Analysis of 2.9-mum water lines enabled accurate determination of rotational temperatures on three dates. The derived H2O rotational temperatures were 138(-5)(+6), 141(-9)(+10), and 94 +/- 3 K on UT 2002 March 22.0, March 23.0, and April 13.8, respectively. Water production rates were retrieved from spectral lines measured in nineteen separate grating settings over seven observing periods. The derived heliocentric dependence of the water production rate was Q = (9.2 +/- 1.1) x 10(28) [R-h((-3.21+/-0.26))] molecules(-1). The spatial of H2O in the coma was consistent with its release directly from the nucleus (as a native source) on all dates. (C) 2003 Elsevier Inc. All rights reserved. C1 Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, NAS,NRC, Greenbelt, MD 20771 USA. Rowan Univ, Dept Chem & Phys, Glassboro, NJ 08028 USA. UCL, Dept Phys & Astron, London WC1E 6BT, England. RP Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. EM ysndr@lepvax.gsfc.nasa.gov RI Tennyson, Jonathan/I-2222-2012; mumma, michael/I-2764-2013; Magee-Sauer, Karen/K-6061-2015; Dello Russo, Neil/G-2727-2015 OI Tennyson, Jonathan/0000-0002-4994-5238; Magee-Sauer, Karen/0000-0002-4979-9875; Dello Russo, Neil/0000-0002-8379-7304 NR 58 TC 71 Z9 71 U1 1 U2 5 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 EI 1090-2643 J9 ICARUS JI Icarus PD MAR PY 2004 VL 168 IS 1 BP 186 EP 200 DI 10.1016/j.icarus.2003.11.004 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 802KC UT WOS:000220161400016 ER PT J AU Filman, RE AF Filman, RE TI Air system information management SO IEEE INTERNET COMPUTING LA English DT Editorial Material C1 NASA, Ames Res Ctr, RIACS, Moffett Field, CA 94035 USA. RP Filman, RE (reprint author), NASA, Ames Res Ctr, RIACS, Moffett Field, CA 94035 USA. EM filman@computer.org NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1089-7801 J9 IEEE INTERNET COMPUT JI IEEE Internet Comput. PD MAR-APR PY 2004 VL 8 IS 2 BP 4 EP 8 DI 10.1109/MIC.2004.1273478 PG 5 WC Computer Science, Software Engineering SC Computer Science GA 800ZY UT WOS:000220067400001 ER PT J AU Lutz, RR Mikulski, IC AF Lutz, RR Mikulski, IC TI Ongoing requirements discovery in high-integrity systems SO IEEE SOFTWARE LA English DT Article; Proceedings Paper CT 11th IEEE Conference on Requirements Engineering CY SEP 08-12, 2003 CL Monterey, CA SP IEEE AB The discovery of new requirements and new requirements knowledge continues throughout the lifetime of many high-integrity embedded systems. Anomaly reports from testing and operations on eight spacecraft at the Jet Propulsion Laboratory revealed four mechanisms for how we discover and resolve requirements. Understanding these mechanisms identifies guidelines to help prevent anomalies found during testing from recurring during operations. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Iowa State Univ, Ames, IA 50011 USA. RP Lutz, RR (reprint author), CALTECH, Jet Prop Lab, MS 125-233,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rlutz@cs.iastate.edu; ines.c.mikulski@jpl.nasa.gov NR 6 TC 7 Z9 7 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0740-7459 J9 IEEE SOFTWARE JI IEEE Softw. PD MAR-APR PY 2004 VL 21 IS 2 BP 19 EP + DI 10.1109/MS.2004.1270757 PG 8 WC Computer Science, Software Engineering SC Computer Science GA 778MG UT WOS:000189244900014 ER PT J AU Pogorzelski, RJ AF Pogorzelski, RJ TI Phased arrays based on oscillators coupled on triangular and hexagonal lattices SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE mutual injection locking; nonCartesian lattices; phased arrays; voltage controlled oscillators ID EQUILATERAL TRIANGLE; WAVE-GUIDES; DYNAMICS AB Phased arrays have been proposed in which a two-dimensional array of voltage-controlled oscillators coupled to nearest neighbors provides excitations for the radiating elements which are properly phased to result in a steerable radiated beam. These arrays have been arranged on a rectangular lattice and the beam is steered by tuning the oscillators along the four edges of the array. Proposed here are similar arrays in which the oscillators are coupled on a triangular lattice or a hexagonal lattice and provide excitations for radiating elements similarly disposed in a planar triangular array. Beam steering is accomplished by tuning the oscillators along the three edges of the array. The dynamic behavior of the arrays is studied via a continuum model and the results compared with those of a full nonlinear discrete analysis and a linearized discrete model. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Pogorzelski, RJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM pogo@jpl.nasa.gov NR 13 TC 12 Z9 15 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAR PY 2004 VL 52 IS 3 BP 790 EP 800 DI 10.1109/TAP.2004.825489 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 813ZJ UT WOS:000220944700017 ER PT J AU Pogorzelski, RJ AF Pogorzelski, RJ TI A frequency tripled two-dimensional coupled oscillator array SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE beam steering; frequency conversion; mutual injection locking; phased arrays; voltage controlled oscillators AB A previously reported two-dimensional (2-D) coupled oscillator array is fitted with an array of frequency triplers and a radiating aperture comprising nine patch elements to create an agile beam transmitter with aperture phase excursion consistent with +/-90degrees of scan. Results of measurements of the aperture phase distribution and the far zone field of this transmitter under both unscanned and scanned conditions are reported. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Pogorzelski, RJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM pogo@jpl.nasa.gov NR 4 TC 5 Z9 6 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAR PY 2004 VL 52 IS 3 BP 907 EP 910 DI 10.1109/TAP.2004.825488 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 813ZJ UT WOS:000220944700033 ER PT J AU Richard, MA AF Richard, MA TI Reply to comments on "Superconducting microstrip antennas: An experimental comparison of two feeding methods" SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Editorial Material C1 NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. RP Richard, MA (reprint author), NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAR PY 2004 VL 52 IS 3 BP 912 EP 912 DI 10.1109/TAP.2004.825495 PG 1 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 813ZJ UT WOS:000220944700036 ER PT J AU Hsu, NC Tsay, SC King, MD Herman, JR AF Hsu, NC Tsay, SC King, MD Herman, JR TI Aerosol properties over bright-reflecting source regions SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE aerosols; algorithm; desert; remote sensing; satellite applications; terrestrial atmosphere ID RESOLUTION IMAGING SPECTRORADIOMETER; TROPOSPHERIC AEROSOLS; SURFACE REFLECTIVITY; OPTICAL-THICKNESS; MINERAL AEROSOLS; LIGHT-SCATTERING; SATELLITE; MODIS; TOMS; DUST AB Retrieving aerosol properties from satellite remote sensing over a bright surface is a challenging problem in the research of atmospheric and land applications. In this paper we propose a new approach to retrieve aerosol properties over surfaces such as arid, semiarid, and urban areas, where the surface reflectance is usually, very, bright in the red part of visible spectrum and in the near infrared, but is much darker in the blue spectral region (i.e., wavelength <500 nm). In order to infer atmospheric properties from these data, a global surface reflectance database of 0.1degrees latitude by 0.1degrees longitude resolution was constructed over bright surfaces for visible wavelengths using the minimum reflectivity, technique (e.g., finding the clearest scene during each season for a given location). The aerosol optical thickness and aerosol type are then determined simultaneously in the algorithm using lookup tables to match the satellite observed spectral radiances. Examples of aerosol optical thickness derived using this algorithm over the Sahara Desert and Arabian Peninsula reveal various dust sources, which are important contributors to airborne dust transported over long distances. Comparisons of the satellite inferred aerosol optical thickness and the values from ground-based Aerosol Robotic Network (AERONET) sun/sky radiometer measurements indicate good agreement (i.e., within 30%) over the sites in Nigeria and Saudi Arabia. This new algorithm, when applied to Moderate Resolution Imaging Spectroradiometer (MODIS), Sea-viewing Wide Field of view Sensor (SeaWiFS), and Global Imager (GLI) satellite data, will provide high spatial resolution (similar to1 km) global information of aerosol optical thickness over bright surfaces on a daily basis. C1 Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Earth Sci Directorate, Greenbelt, MD 20771 USA. RP Hsu, NC (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. EM hsu@wrabbit.gsfc.nasa.gov RI King, Michael/C-7153-2011; Hsu, N. Christina/H-3420-2013; Tsay, Si-Chee/J-1147-2014; OI King, Michael/0000-0003-2645-7298; Herman, Jay/0000-0002-9146-1632 NR 39 TC 448 Z9 469 U1 10 U2 68 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAR PY 2004 VL 42 IS 3 BP 557 EP 569 DI 10.1109/TGRS.2004.824067 PG 13 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 813KM UT WOS:000220906000008 ER PT J AU Storey, JC Choate, MJ Meyer, DJ AF Storey, JC Choate, MJ Meyer, DJ TI A geometric performance assessment of the EO-1 advanced land imager SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE Advanced Land Imager (ALI); band registration; geometric accuracy; Landsat ID CALIBRATION AB The Earth Observing 1 (EO-1) Advanced Land Imager (ALI) demonstrates technology applicable to a successor system to the Landsat Thematic Mapper series. A study of the geometric performance characteristics of the ALI was conducted under the auspices of the EO-1 Science Validation Team. This study evaluated ALI performance with respect to absolute pointing knowledge, focal plane sensor chip assembly alignment, and hand-to-hand registration for purposes of comparing this new technology to the heritage Landsat systems. On-orbit geometric calibration procedures were developed that allowed the generation of ALI geometrically corrected products that compare favorably with their Landsat 7 counterparts with respect to absolute geodetic accuracy, internal image geometry, and band registration. C1 NASA, Goddard Space Flight Ctr, Sci Applicat Int Corp, Greenbelt, MD 20771 USA. US Geol Survey, EROS Data Ctr, Sci Applicat Int Corp, Sioux Falls, SD 57198 USA. RP Storey, JC (reprint author), NASA, Goddard Space Flight Ctr, Sci Applicat Int Corp, Code 661, Greenbelt, MD 20771 USA. EM James.C.Storey.1@gsfc.nasa.gov; choate@usgs.gov; dmeyer@usgs.gov NR 6 TC 14 Z9 14 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAR PY 2004 VL 42 IS 3 BP 602 EP 607 DI 10.1109/TGRS.2003.820603 PG 6 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 813KM UT WOS:000220906000013 ER PT J AU Stevens, RM Nguyen, CV Meyyappan, M AF Stevens, RM Nguyen, CV Meyyappan, M TI Carbon nanotube scanning probe for imaging in aqueous environment SO IEEE TRANSACTIONS ON NANOBIOSCIENCE LA English DT Article DE atomic force microscopy (AFM); bionanotechnology; carbon nanotubes (CNTs); nanotechnology; scanning probe microscopy ID MICROSCOPY TIPS; RESOLUTION; GROWTH AB Carbon nanotubes (CNTs) used as a probe for scanning probe microscopy has become one of the many potential usages of CNTs that is finding real applications in scientific research and industrial communities. It has been proposed that the unique mechanical buckling properties of the CNT would lessen the imaging force exerted on the sample and, thus, make CNT scanning probes ideal for imaging soft materials, including biological samples in liquid environments. The hydrophobic nature of the CNT graphitic sidewall is clearly chemically incompatible with the aqueous solution requirements in some biological imaging applications. In this paper, we present electron micrograph results demonstrating the instability of CNT scanning probes when submerged in aqueous solution. Moreover, we also introduce a novel approach to resolve this chemical incompatibility problem. By coating the CNT probe with ethylenediamine, thus rendering the CNT probe less hydrophobic, we demonstrate the liquid imaging capability of treated CNT probes. Experimental data for imaging in aqueous solutions are presented, which include an ultrathin Ir film and DNA molecules on a mica surface. C1 NASA, Ames Res Ctr, ELORET Corp, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Stevens, RM (reprint author), NASA, Ames Res Ctr, ELORET Corp, Ctr Nanotechnol, Moffett Field, CA 94035 USA. EM rstevens@mail.arc.nasa.gov NR 9 TC 31 Z9 32 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1536-1241 J9 IEEE T NANOBIOSCI JI IEEE Trans. Nanobiosci. PD MAR PY 2004 VL 3 IS 1 BP 56 EP 60 DI 10.1109/TNB.2004.824275 PG 5 WC Biochemical Research Methods; Nanoscience & Nanotechnology SC Biochemistry & Molecular Biology; Science & Technology - Other Topics GA 808ST UT WOS:000220589500011 PM 15382645 ER PT J AU Lutz, RR Mikulski, IC AF Lutz, RR Mikulski, IC TI Empirical analysis of safety-critical anomalies during operations SO IEEE TRANSACTIONS ON SOFTWARE ENGINEERING LA English DT Article DE software and system safety; diagnostics; maintenance process; product metrics ID SOFTWARE; CLASSIFICATION AB Analysis of anomalies that occur during operations is an important means of improving the quality of current and future software. Although the benefits of anomaly analysis of operational software are widely recognized, there has been relatively little research on anomaly analysis of safety-critical systems. In particular, patterns of software anomaly data for operational, safety-critical systems are not well understood. This paper presents the results of a pilot study using Orthogonal Defect Classification (ODC) to analyze nearly two hundred such anomalies on seven spacecraft systems. These data show several unexpected classification patterns such as the causal role of difficulties accessing or delivering data, of hardware degradation, and of rare events. The anomalies often revealed latent software requirements that were essential for robust, correct operation of the system. The anomalies also caused changes to documentation and to operational procedures to prevent the same anomalous situations from recurring. Feedback from operational anomaly reports helped measure the accuracy of assumptions about operational profiles, identified unexpected dependencies among embedded software and their systems and environment, and indicated needed improvements to the software, the development process, and the operational procedures. The results indicate that, for long-lived, critical systems, analysis of the most severe anomalies can be a useful mechanism both for maintaining safer, deployed systems and for building safer, similar systems in the future. C1 Iowa State Univ, Dept Comp Sci, Ames, IA 50011 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Iowa State Univ, Dept Comp Sci, 226 Atanasoff Hall, Ames, IA 50011 USA. EM rlutz@cs.iastate.edu; ines.c.mikulski@jpl.nasa.gov NR 29 TC 28 Z9 29 U1 0 U2 7 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0098-5589 EI 1939-3520 J9 IEEE T SOFTWARE ENG JI IEEE Trans. Softw. Eng. PD MAR PY 2004 VL 30 IS 3 BP 172 EP 180 DI 10.1109/TSE.2004.1271171 PG 9 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 803BN UT WOS:000220206700003 ER PT J AU Loncar, M Yoshie, T Okamoto, K Qiu, YM Vuckovic, J Scherer, A AF Loncar, M Yoshie, T Okamoto, K Qiu, YM Vuckovic, J Scherer, A TI Planar photonic crystal nanolasers (I): Porous cavity lasers SO IEICE TRANSACTIONS ON ELECTRONICS LA English DT Article DE photonic crystals; photonic bandgap; laser; nanophotonics; nanofabrication; FDTD ID ROOM-TEMPERATURE OPERATION; DEFECT MODES; QUANTUM-DOT; SLAB; MICROCAVITIES; EMISSION AB We have designed, fabricated and characterized efficient optical resonators and low-threshold lasers based on planar photonic crystal concept. Lasers with InGa-AsP quantum well active material emitting at 1550 nm were optically pumped, and room temperature lasing was observed at threshold powers below 220muW. Porous high quality factor cavity that we have developed confines light in the air region and therefore our lasers are ideally suited for investigation of interaction between light and matter on a nanoscale level. We have demonstrated the operation of photonic crystal lasers in different ambient organic solutions, and we have showed that planar photonic crystal lasers can be used to perform spectroscopic tests on femtoliter volumes of analyte. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. CALTECH, Dept Elect Engn, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, In Situ Technol & Expt Syst Sect, Pasadena, CA 91109 USA. Stanford Univ, Ginzton Lab, Stanford, CA 94305 USA. RP Harvard Univ, Div Engn & Appl Sci, 9 Oxford St, Cambridge, MA 02138 USA. EM loncar@deas.harvard.edu RI Yoshie, Tomoyuki/C-3567-2008; Okamoto, Koichi/D-7695-2014 OI Okamoto, Koichi/0000-0002-2658-3000 NR 24 TC 5 Z9 5 U1 0 U2 3 PU IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG PI TOKYO PA KIKAI-SHINKO-KAIKAN BLDG, 3-5-8, SHIBA-KOEN, MINATO-KU, TOKYO, 105-0011, JAPAN SN 1745-1353 J9 IEICE T ELECTRON JI IEICE Trans. Electron. PD MAR PY 2004 VL E87C IS 3 BP 291 EP 299 PG 9 WC Engineering, Electrical & Electronic SC Engineering GA 802KU UT WOS:000220163200006 ER PT J AU Hammond, DK Becker, JL Elliott, TF Holubec, K Baker, TL Love, JE AF Hammond, D. K. Becker, J. L. Elliott, T. F. Holubec, K. Baker, T. L. Love, J. E. TI Cell growth and cytokine production of human mixed Mullerian tumor (LNI) cells grown on the International Space Station (ISS) SO IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY-ANIMAL LA English DT Meeting Abstract C1 [Hammond, D. K.; Elliott, T. F.; Holubec, K.; Baker, T. L.] Wyle Life Sci, Houston, TX USA. [Becker, J. L.] Natl Space Biomed Res Inst, Houston, TX USA. [Becker, J. L.] Baylor Coll Med, Houston, TX 77030 USA. [Love, J. E.] NASA, Lyndon B Johnson Space Ctr, Bio Syst Off, Houston, TX 77058 USA. EM dianne.hammond1@jsc.nasa.gov NR 0 TC 0 Z9 0 U1 1 U2 3 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1071-2690 J9 IN VITRO CELL DEV-AN JI In Vitro Cell. Dev. Biol.-Anim. PD SPR PY 2004 VL 40 BP 80A EP 80A PG 1 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA V44ID UT WOS:000202995500299 ER PT J AU Liebe, C AF Liebe, C TI Solar compass chip SO INTECH LA English DT Editorial Material C1 CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Liebe, C (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91125 USA. EM carl.c.liebe@jpl.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU INSTRUMENT SOC AMER PI RES TRIANGLE PK PA 67 ALEXANDER DRIVE, RES TRIANGLE PK, NC 27709 USA SN 0192-303X J9 INTECH JI Intech PD MAR PY 2004 VL 51 IS 3 BP 57 EP 57 PG 1 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 805XC UT WOS:000220398000022 ER PT J AU Chamberlain, RG AF Chamberlain, RG TI 20/30 hindsight: What is operations research? SO INTERFACES LA English DT Editorial Material DE professional, comments on C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Chamberlain, RG (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rgc@jpl.nasa.gov NR 1 TC 1 Z9 1 U1 0 U2 0 PU INST OPERATIONS RESEARCH MANAGEMENT SCIENCES PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2909 USA SN 0092-2102 J9 INTERFACES JI Interfaces PD MAR-APR PY 2004 VL 34 IS 2 BP 123 EP 123 DI 10.1287/inte.1030.0071 PG 1 WC Management; Operations Research & Management Science SC Business & Economics; Operations Research & Management Science GA 813LN UT WOS:000220908700007 ER PT J AU Chen, S Tao, G Joshi, SM AF Chen, S Tao, G Joshi, SM TI Adaptive actuator failure compensation designs for linear systems SO INTERNATIONAL JOURNAL OF CONTROL AUTOMATION AND SYSTEMS LA English DT Article DE actuator failure; adaptive control; failure compensation; robust perfortnance ID RECONFIGURABLE FLIGHT CONTROL; FAULT-TOLERANT CONTROL; STATE-FEEDBACK CONTROL; NONLINEAR-SYSTEMS; TRACKING CONTROL; RELIABLE CONTROL; DYNAMIC-SYSTEMS; DIAGNOSIS; REDUNDANCY; SCHEME AB This paper surveys some existing direct adaptive feedback control schemes for linear time-invariant systems with actuator failures characterized by the failure pattern that some inputs are stuck at some unknown fixed or varying values at unknown time instants, and applications of those schemes to aircraft flight control system models. Controller structures, plant-model matching conditions, and adaptive laws to update controller parameters are investigated for the following cases for continuous-time systems: state tracking using state feedback, output tracking using state feedback, and output tracking using output feedback. In addition, a discrete-time output tracking design using output feedback is presented. Robustness of this design with respect to unmodeled dynamics and disturbances is addressed using a modified robust adaptive law. C1 Univ Michigan, Dept Naval Architecture & Marine Engn, Ann Arbor, MI 48109 USA. Univ Virginia, Dept Elect & Comp Engn, Charlottesville, VA 22903 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Univ Michigan, Dept Naval Architecture & Marine Engn, Ann Arbor, MI 48109 USA. EM shchen@umich.edu; gt9s@ee.virginia.edu; s.m.joshi@larc.nasa.gov NR 58 TC 153 Z9 156 U1 4 U2 17 PU INST CONTROL ROBOTICS & SYSTEMS, KOREAN INST ELECTRICAL ENGINEERS PI BUCHEON PA BUCHEON TECHNO PARK 401-1506, 193 YAKDAE-DONG WONMI-GU, BUCHEON, GYEONGGI-DO 420-734, SOUTH KOREA SN 1598-6446 EI 2005-4092 J9 INT J CONTROL AUTOM JI Int. J. Control Autom. Syst. PD MAR PY 2004 VL 2 IS 1 BP 1 EP 14 PG 14 WC Automation & Control Systems SC Automation & Control Systems GA 885MR UT WOS:000226161900001 ER PT J AU Zhang, H Mudawar, I Hasan, MM AF Zhang, H Mudawar, I Hasan, MM TI Investigation of interfacial behavior during the flow boiling CHF transient SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article DE critical heat flux; flow boiling ID CRITICAL HEAT-FLUX; TRIGGER MECHANISM; ROUND TUBES; PREDICTION; MODEL; ORIENTATION; WALL; LENGTH; LONG AB Vertical upflow boiling experiments were performed in pursuit of identifying the trigger mechanism for subcooled flow boiling critical heat flux (CHF). While virtually all prior studies on flow boiling CHF concern the prediction or measurement of conditions that lead to CHF, this study is focused on events that take place during the CHF transient. High-speed video imaging and photomicrographic techniques were used to record the transient behavior of interfacial features from the last steady-state power level before CHF until the moment of power cut-off following CHF. The video records show the development of a wavy vapor layer which propagates along the heated wall, permitting cooling prior to CHF only in wetting fronts corresponding to the wave troughs. Image analysis software was developed to estimate void fraction from the individual video images. The void fraction records for subcooled flow boiling show the CHF transient is accompanied by gradual lift-off of wetting fronts culminating in some maximum vapor layer mean thickness, following which the vapor layer begins to thin down as the transition to film boiling ensues. This study proves the interfacial lift-off model, which has been validated for near-saturated flow boiling CHF, is equally valid for subcooled conditions. (C) 2003 Elsevier Ltd. All rights reserved. C1 Purdue Univ, Sch Mech Engn, Boiling & Twophase Flow Lab, W Lafayette, IN 47907 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Mudawar, I (reprint author), Purdue Univ, Sch Mech Engn, Boiling & Twophase Flow Lab, Mech Engn Bldg, W Lafayette, IN 47907 USA. EM mudawar@ecn.purdue.edu NR 27 TC 19 Z9 20 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0017-9310 J9 INT J HEAT MASS TRAN JI Int. J. Heat Mass Transf. PD MAR PY 2004 VL 47 IS 6-7 BP 1275 EP 1288 DI 10.1016/j.ijheatmasstransfer.2003.09.014 PG 14 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA 768BJ UT WOS:000188508100014 ER PT J AU Hill, SA AF Hill, SA TI Determination of an empirical model for the prediction of penetration hole diameter in thin plates from hypervelocity impact SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article AB The purpose of this work is to identify an empirical relationship that describes the size of the hole created in a thin plate from a hypervelocity impact in terms of the material properties and geometry of both the projectile and target. A multivariable power series was selected as the form of the mathematical model to develop this empirical relationship. Material properties and geometry of both the projectile and target were selected as the independent variables of this model to predict the hole diameters in targets. Comparison with historical equations reveals that these new models are more accurate predictors of target hole diameters. This statement is based on a one-to-one comparison of the equations using both the data utilized in developing the new models and "new", independent data. Published by Elsevier Ltd. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Hill, SA (reprint author), NASA, Langley Res Ctr, MS 431, Hampton, VA 23681 USA. EM s.a.hill@larc.nasa.gov NR 19 TC 8 Z9 8 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD MAR PY 2004 VL 30 IS 3 BP 303 EP 321 DI 10.1016/S0734-743X(03)00079-4 PG 19 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 774GU UT WOS:000188972100005 ER PT J AU Williams, JG Turyshev, SG Murphy, TW AF Williams, JG Turyshev, SG Murphy, TW TI Improving LLR tests of gravitational theory SO INTERNATIONAL JOURNAL OF MODERN PHYSICS D LA English DT Article DE gravitational physics; lunar laser ranging; equivalence principle; general relativity ID EQUIVALENCE PRINCIPLE; GENERAL-RELATIVITY; MASSIVE BODIES; COSMIC ACCELERATION; LUNAR MOTION; DARK-MATTER; GRAVITY; MOON; DEFLECTION; VERIFICATION AB Accurate analysis of precision ranges to the Moon has provided several tests of gravitational theory including the Equivalence Principle, geodetic precession, parameterized post-Newtonian (PPN) parameters gamma and beta, and the constancy of the gravitational constant G. Since the beginning of the experiment in 1969, the uncertainties of these tests have decreased considerably as data accuracies have improved and data time span has lengthened. We are exploring the modeling improvements necessary to proceed from cut to turn range accuracies enabled by the new Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) currently under development in New Mexico. This facility will be able to make a significant contribution to the solar system tests of fundamental and gravitational physics. In particular, the Weak and Strong Equivalence Principle tests would have a sensitivity approaching 10(-14), yielding sensitivity for the SEP violation parameter eta of similar to 3 x 10(-5), nu(2)/c(2) general relativistic effects would be tested to better than 0.1%, and measurements of the relative change in the gravitational constant, G/G, would be similar to 0.1% the inverse age of the universe. Having this expected accuracy in mind, we discusses the current techniques, methods and existing physical models used to process the LLR data. We also identify the challenges for modeling and data analysis that the LLR community faces today in order to take full advantage of the new APOLLO ranging station. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Turyshev, SG (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 46 TC 66 Z9 67 U1 0 U2 3 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-2718 J9 INT J MOD PHYS D JI Int. J. Mod. Phys. D PD MAR PY 2004 VL 13 IS 3 BP 567 EP 582 DI 10.1142/S0218271804004682 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 814QB UT WOS:000220988100007 ER PT J AU Moxey, LE AF Moxey, LE TI Mount Hudson's 1991 eruption provides Holocene palaeoclimatic insights SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID SOUTHERN ANDES; VOLCANO; SATELLITE; PINATUBO; TEPHRA AB A study of the 1991 eruption of Mt Hudson, a volcano located in southern Chile, was carried out using NOAA Advanced Very High Resolution Radiometer (AVHRR), Total Ozone Mapping Spectrometer (TOMS) and Landsat-7 "Enhanced Thematic Mapper (ETM+)" imagery. It investigated the plume movements and dispersal trajectories of the volcanic material ejected during this eruption and identified the potential air-fall regions for Mt Hudson's Holocene eruptions. For validation purposes, the satellite imagery was combined with field data and isopach distributions of the August 1991 eruption and two Holocene eruptions, dated at 3600 BP and 6700 BP. The elliptical isopach distributions and the well-defined dispersal axes of the 6700 BP and August 1991 events indicate the existence of stable wind conditions at the time of the eruptions. In contrast, the 3600 BP event presents a circular isopach distribution, reflecting the dispersal effects of variable winds. This contribution will provide further insights regarding the palaeoclimatic conditions existing at the time of the studied eruptions, and also aid in the selection of field locations for future volcanological studies in southern Patagonia. C1 Univ Florida, Dept Geol Sci, Gainesville, FL 32611 USA. RP Moxey, LE (reprint author), Natl Marine Fisheries Serv, NOAA, JIMAR, Honolulu Lab,SW Fisheries Sci Ctr, 2570 Dole St, Honolulu, HI 96822 USA. EM Lucas.Moxey@noaa.gov NR 29 TC 1 Z9 1 U1 2 U2 3 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD MAR PY 2004 VL 25 IS 6 BP 1053 EP 1062 DI 10.1080/0143116031000084288 PG 10 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 762RZ UT WOS:000187997100001 ER PT J AU Mckay, CP AF Mckay, CP TI Scientific goals for Martian expeditions SO JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY LA English DT Article; Proceedings Paper CT Meeting on Martian Expedition Planning CY FEB 24, 2003 CL BRITISH INTERPLANETARY SOC, LONDON, ENGLAND HO BRITISH INTERPLANETARY SOC DE mars; life; science; exploration ID LIQUID WATER; GLOBAL DISTRIBUTION; MARS; DURATION AB Science will be an important goal for martian expeditions, as it has been for past and present expeditions on Earth. The search for evidence of a second genesis of life on Mars, and investigating the biochemical nature of that life are the scientific questions that are most compelling and capable of sustaining major scientific expeditions. Promising target sites include subsurface ecosystems and ancient organisms preserved in salt deposits or frozen in permafrost. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Mckay, CP (reprint author), NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. EM cmckay@mail.arc.nasa.gov NR 21 TC 1 Z9 1 U1 0 U2 1 PU BRITISH INTERPLANETARY SOC PI LONDON PA 27-29 S LAMBETH RD, LONDON SW8 1SZ, ENGLAND SN 0007-084X J9 JBIS-J BRIT INTERPLA JI JBIS-J. Br. Interplanet. Soc. PD MAR-APR PY 2004 VL 57 IS 3-4 BP 87 EP 91 PG 5 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Geology GA 771KH UT WOS:000188783800003 ER PT J AU Cockell, CS AF Cockell, CS TI Field innovations in support of Martian polar expeditions SO JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY LA English DT Article; Proceedings Paper CT Meeting on Martian Expedition Planning CY FEB 24, 2003 CL BRITISH INTERPLANETARY SOC, LONDON, ENGLAND HO BRITISH INTERPLANETARY SOC DE polar; Mars; expedition; ISRU; Antarctica AB The Martian poles present a challenging environment for expedition planners. I review and describe innovations in support of human Martian polar expeditions that are a direct extrapolation of terrestrial polar exploration equipment. Ball tents provide an environment for de-suiting at the end of daily expedition traverse and can be used to establish temporary field camps and depots for transpolar expeditions or deep-field scientific outposts. Sublimation poles, netting and heating boxes allow for the harvesting of polar ices for water, oxygen and fuel production. Pressurization of ices prior to melting allows liquid water to be collected, thus reducing energy expenditure compared to ice vaporization. Sublimation nets additionally are used for the removal of CO2 frost from expedition equipment. Human mobility can be achieved with sledges and rovers. These innovations, when combined, make possible the planning of human scientific and expeditionary EVAs on the Martian polar ice caps. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Cockell, CS (reprint author), NASA, Ames Res Ctr, M-S 245-3, Moffett Field, CA 94035 USA. EM csco@bas.ac.uk NR 10 TC 1 Z9 1 U1 1 U2 1 PU BRITISH INTERPLANETARY SOC PI LONDON PA 27-29 S LAMBETH RD, LONDON SW8 1SZ, ENGLAND SN 0007-084X J9 JBIS-J BRIT INTERPLA JI JBIS-J. Br. Interplanet. Soc. PD MAR-APR PY 2004 VL 57 IS 3-4 BP 92 EP 98 PG 7 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Geology GA 771KH UT WOS:000188783800004 ER PT J AU Jones, JA Barratt, M Effenhauser, R Cockell, CS Lee, P AF Jones, JA Barratt, M Effenhauser, R Cockell, CS Lee, P TI Medical issues for a human mission to Mars and Martian surface expeditions SO JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY LA English DT Article; Proceedings Paper CT Meeting on Martian Expedition Planning CY FEB 24, 2003 CL BRITISH INTERPLANETARY SOC, LONDON, ENGLAND HO BRITISH INTERPLANETARY SOC DE Mars; expedition; medical; countermeasures; physiology ID RADIATION AB The medical issues for an exploratory class mission to Mars are myriad and challenging. They include hazards from the space environment, such as space vacuum and radiation; hazards on the planetary surface such as micrometeoroids and Martian dust, and constitutional medical hazards, like appendicitis and tooth abscess. They include hazards in the transit vehicle like foreign bodies and toxic atmospheres, and hazards in the habitat like decompression and combustion events. They also include human physiological adaptation to variable conditions of reduced gravity and prolonged isolation and confinement. The health maintenance program for a Mars mission will employ strategies of disease prevention, early detection, and contingency management, to mitigate the risks of spaceflight and exploration. Countermeasures for altered gravity conditions will allow crewmembers to maintain high levels of performance and nominal physiologic functioning. Despite all of these issues, given sufficient redundancy in on-board life support systems, there are no medical show-stoppers for the first human exploratory class missions. C1 NASA, JSC, Houston, TX 77058 USA. NASA, Ames Res Ctr, Search Extraterr Intelligence SETI Inst, Moffett Field, CA 94035 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Jones, JA (reprint author), NASA, JSC, SD2,2101 Nasa Rd 1, Houston, TX 77058 USA. NR 23 TC 4 Z9 5 U1 1 U2 3 PU BRITISH INTERPLANETARY SOC PI LONDON PA 27-29 S LAMBETH RD, LONDON SW8 1SZ, ENGLAND SN 0007-084X J9 JBIS-J BRIT INTERPLA JI JBIS-J. Br. Interplanet. Soc. PD MAR-APR PY 2004 VL 57 IS 3-4 BP 144 EP 160 PG 17 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Geology GA 771KH UT WOS:000188783800011 ER PT J AU Roy, B Halverson, JB Wang, JH AF Roy, B Halverson, JB Wang, JH TI The influence of radiosonde ''age'' on TRMM field campaign soundings humidity correction SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID TOGA COARE; CONVECTIVE SYSTEMS AB Hundreds of Vaisala sondes with an RS80-H Humicap thin-film capacitor humidity sensor were launched during the Tropical Rainfall Measuring Mission (TRMM) field campaigns ( 1999) Large Scale Biosphere - Atmosphere (LBA) experiment held in Brazil and the Kwajalein Experiment (KWAJEX) held in the Republic of the Marshall Islands. Six humidity error correction algorithms were used primarily for applying system-bias correction to RS80-H humidity data. All TRMM field campaign Vaisala humidity soundings were corrected for dry bias using this algorithm. An overall improvement of 3% RH for daytime and 5% RH for nighttime soundings was achieved. Sonde age was ascertained using respective serial numbers ( in this case the range is 0.06 - 2.07 yr) and used in the algorithm for calculation of sensor aging error and chemical contamination errors. Chemical contamination error is also found to be a dominant error source. Daytime sensor-arm heating for the first 50 s of the sonde launch is found to bear a cosine variation with sonde age. Surface reference temperature and sonde registered surface temperature are both used for calculating surface saturation vapor pressure, which in turn is used for sensor-arm-heating error estimation during the first 50 s. Site-mean CAPE values are found to increase significantly after correction. It is suggested that sonde surface temperature error must also be corrected for sonde age while using the present RS80-H correction algorithm. An age - height plot of the differences between the uncorrected and corrected specific humidity value for all Vaisala soundings shows an age-dependent increase ( approximately 3.4 g kg(-1) for 2-yr-old sondes). Variation of specific humidity difference was not found to be very significant for the upper levels when the sensor is less than 1.25 yr old. C1 NASA, Goddard Space Flight Ctr, Mesoscale Proc Branch, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Greenbelt, MD USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. Natl Ctr Atmospher Res, Atmospher Technol Div, Boulder, CO 80307 USA. RP Roy, B (reprint author), US EPA, MEARB, Atmospher Modeling Div, 109 TW Alexander Dr, Res Triangle Pk, NC 27711 USA. EM Roy.Dev@EPA.gov NR 14 TC 5 Z9 5 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD MAR PY 2004 VL 21 IS 3 BP 470 EP 480 DI 10.1175/1520-0426(2004)021<0470:TIORAO>2.0.CO;2 PG 11 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 805BA UT WOS:000220340600006 ER PT J AU Zibordi, G Hooker, SB Mueller, J Lazin, G AF Zibordi, G Hooker, SB Mueller, J Lazin, G TI Characterization of the immersion factor for a series of in-water optical radiometers SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID IRRADIANCE AB Spectral immersion factors, I-f (lambda), account for the difference between the in- air and in- water absolute response of submersible radiometers and are required to properly apply the in- air absolute calibration of the sensor when used underwater. The use of the so- called typical values for a series of in- water radiometers is a source of uncertainty because of intrinsic instrument- to- instrument differences in the optics. To investigate this source of uncertainty, in addition to uncertainties associated with determining the immersion factors using a laboratory method, a sample of nine radiometers from the same series of instruments was characterized by three different laboratories. A comparison of the immersion factor characterizations from the three laboratories indicates average intralaboratory measurement repeatabilities ranging from 0.3% to 0.6%, which were evaluated using multiple characterizations of the same reference radiometer and defined by two standard deviations. Interlaboratory relative uncertainties, evaluated with I-f (lambda) data from the nine sample radiometers, show average percent differences ranging from 20.5% to 0.6%. The dispersion of I-f (lambda) values across all the radiometers show values up to 5% in the red part of the spectrum with a spectral average of 2% ( defined by two standard deviations). Typical I-f (lambda) values, computed with data from the so- called trusted radiometers (i.e., those not showing extreme outlier values), are also presented with their maximum uncertainties and a discussion on their spectral dependence. C1 Commiss European Communities, Joint Res Ctr, Inland & Marine Waters Unit, IES IMW, I-21020 Ispra, VA, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. San Diego State Univ, Ctr Hydroopt & Remote Sensing, San Diego, CA 92182 USA. Satlantic Inc, Halifax, NS, Canada. RP Zibordi, G (reprint author), Commiss European Communities, Joint Res Ctr, Inland & Marine Waters Unit, IES IMW, TP272, I-21020 Ispra, VA, Italy. EM giuseppe.zibordi@jrc.it RI Hooker, Stanford/E-2162-2012 NR 19 TC 16 Z9 16 U1 1 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD MAR PY 2004 VL 21 IS 3 BP 501 EP 514 DI 10.1175/1520-0426(2004)021<0501:COTIFF>2.0.CO;2 PG 14 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 805BA UT WOS:000220340600010 ER PT J AU Komjathy, A Armatys, M Masters, D Axelrad, P Zavorotny, V Katzberg, S AF Komjathy, A Armatys, M Masters, D Axelrad, P Zavorotny, V Katzberg, S TI Retrieval of ocean surface wind speed and wind direction using reflected GPS signals SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID SEA-SURFACE; ALTIMETRY; SCATTERING; SPECTRUM; SYSTEM; PARIS AB Global positioning system (GPS) signals reflected from the ocean surface can be used for various remote sensing purposes. Some possibilities include measurements of surface roughness characteristics from which the rms of wave slopes, wind speed, and direction could be determined. In this paper, reflected GPS measurements that were collected using aircraft with a delay mapping GPS receiver are used to explore the possibility of determining ocean surface wind speed and direction during flights to Hurricanes Michael and Keith in October 2000. To interpret the GPS data, a theoretical model is used to describe the correlation power of the reflected GPS signals for different time delays as a function of geometrical and sea-roughness parameters. The model employs a simple relationship between surface-slope statistics and both a wind vector and wave age or fetch. Therefore, for situations when this relationship holds there is a possibility of indirectly measuring the wind speed and the wind direction. Wind direction estimates are based on a multiple-satellite nonlinear least squares solution. The estimated wind speed using surface-reflected GPS data collected at wind speeds between 5 and 10 m s(-1) shows an overall agreement of better than 2 m s(-1) with data obtained from nearby buoy data and independent wind speed measurements derived from TOPEX/ Poseidon, European Remote Sensing (ERS), and QuikSCAT observations. GPS wind retrievals for strong winds in the close vicinity to and inside the hurricane are significantly less accurate. Wind direction agreement with QuikSCAT measurements appears to be at the 308 level when the airplane has both a stable flight level and a stable flight direction. Discrepancies between GPS retrieved wind speeds/directions and those obtained by other means are discussed and possible explanations are proposed. C1 CALTECH, Jet Prop Lab, CCAR, Pasadena, CA 91109 USA. NOAA, Environm Technol Lab, Boulder, CO USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Komjathy, A (reprint author), CALTECH, Jet Prop Lab, CCAR, MS 238-643A,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Attila.Komjathy@jpl.nasa.gov NR 30 TC 50 Z9 53 U1 0 U2 11 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD MAR PY 2004 VL 21 IS 3 BP 515 EP 526 DI 10.1175/1520-0426(2004)021<0515:ROOSWS>2.0.CO;2 PG 12 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 805BA UT WOS:000220340600011 ER PT J AU Murphy, EF Gordon, JD Mullen, A AF Murphy, EF Gordon, JD Mullen, A TI A preliminary study exploring the value changes taking place in the United States since the September 11, 2001 terrorist attack on the World Trade Center in New York SO JOURNAL OF BUSINESS ETHICS LA English DT Article DE cultural upheaval; socialization; value change ID VALUE SELF-CONFRONTATION; SOCIALIZATION VALUES; BEHAVIOR; ATTITUDES; CONSUMER; CHILD AB This study was a preliminary exploration of the value changes taking place in the United States since the September 11, 2001 terrorist attack on the World Trade Center in New York, which was a significant emotional event or cultural upheaval. Rokeach told us that "a person's total value system may undergo change as a result of socialization, therapy, or cultural upheaval..." (Rokeach, The Nature of Human Values, 1973, p. 37). The researchers explored the value changes of 500 aviation industry employees before the attack and 500 after the attack. The statistically significant research results showed a total of twenty-seven of thirty-six values changed. Before the attack respondents valued much higher self-esteem and self-actualization values like A Sense of Accomplishment and Self-Respect. After the attack respondents placed a much higher value importance on survival, safety and security values like A World at Peace, Freedom, Family Security, National Security, Mature Love, Salvation, and True Friendship. C1 Embry Riddle Aeronaut Univ, Travis AFB Resident Ctr, Vacaville, CA 95687 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Embry Riddle Aeronaut Univ, Oakland Resident Ctr, Oakland, CA 94621 USA. FAA, Technol Requirements Branch, Flight Stand Serv, Weather & Air Traff Syst, Washington, DC USA. RP Murphy, EF (reprint author), Embry Riddle Aeronaut Univ, Travis AFB Resident Ctr, 844 Sapphire Circle, Vacaville, CA 95687 USA. NR 57 TC 9 Z9 9 U1 2 U2 8 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-4544 J9 J BUS ETHICS JI J. Bus. Ethics PD MAR PY 2004 VL 50 IS 1 BP 81 EP 96 PG 16 WC Business; Ethics SC Business & Economics; Social Sciences - Other Topics GA 816EF UT WOS:000221092500007 ER PT J AU Rind, D Shindell, D Perlwitz, J Lerner, J Lonergan, P Lean, J McLinden, C AF Rind, D Shindell, D Perlwitz, J Lerner, J Lonergan, P Lean, J McLinden, C TI The relative importance of solar and anthropogenic forcing of climate change between the Maunder Minimum and the present SO JOURNAL OF CLIMATE LA English DT Article ID DOUBLED CO2 CLIMATE; STRATOSPHERIC OZONE; GREENHOUSE-GAS; TREE-RING; TEMPERATURE VARIABILITY; IRRADIANCE VARIATIONS; MIDDLE ATMOSPHERE; PAST MILLENNIUM; GLOBAL CLIMATE; NORTH-ATLANTIC AB The climate during the Maunder Minimum is compared with current conditions in GCM simulations that include a full stratosphere and parameterized ozone response to solar spectral irradiance variability and trace gas changes. The Goddard Institute for Space Studies (GISS) Global Climate/Middle Atmosphere Model (GCMAM) coupled to a q-flux/mixed-layer model is used for the simulations, which begin in 1500 and extend to the present. Experiments were made to investigate the effect of total versus spectrally varying solar irradiance changes; spectrally varying solar irradiance changes on the stratospheric ozone/climate response with both preindustrial and present trace gases; and the impact on climate and stratospheric ozone of the preindustrial trace gases and aerosols by themselves. The results showed that 1) the Maunder Minimum cooling relative to today was primarily associated with reduced anthropogenic radiative forcing, although the solar reduction added 40% to the overall cooling. There is no obvious distinguishing surface climate pattern between the two forcings. 2) The global and tropical response was greater than 1degreesC, in a model with a sensitivity of 1.2degreesC (W m(-2))(-1). To reproduce recent low-end estimates would require a sensitivity one-fourth as large. 3) The global surface temperature change was similar when using the total and spectral irradiance prescriptions, although the tropical response was somewhat greater with the former, and the stratospheric response greater with the latter. 4) Most experiments produce a relative negative phase of the North Atlantic Oscillation/Arctic Oscillation (NAO/AO) during the Maunder Minimum, with both solar and anthropogenic forcing equally capable, associated with the tropical cooling and relative poleward Eliassen-Palm (EP) flux refraction. 5) A full stratosphere appeared to be necessary for the negative AO/NAO phase, as was the case with this model for global warming experiments, unless the cooling was very large, while the ozone response played a minor role and did not influence surface temperature significantly. 6) Stratospheric ozone was most affected by the difference between present-day and preindustrial atmospheric composition and chemistry, with increases in the upper and lower stratosphere during the Maunder Minimum. While the estimated UV reduction led to ozone decreases, this was generally less important than the anthropogenic effect except in the upper midstratosphere, as judged by two different ozone photochemistry schemes. 7) The effect of the reduced solar irradiance on stratospheric ozone and on climate was similar in Maunder Minimum and current atmospheric conditions. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. SGT Corp, New York, NY USA. USN, Res Lab, Washington, DC 20375 USA. Meteorol Serv Canada, Downsview, ON, Canada. RP Rind, D (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM drind@giss.nasa.gov RI Perlwitz, Judith/B-7201-2008; McLinden, Chris/A-7710-2010; Shindell, Drew/D-4636-2012; OI Perlwitz, Judith/0000-0003-4061-2442; McLinden, Chris/0000-0001-5054-1380; Lean, Judith/0000-0002-0087-9639 NR 50 TC 66 Z9 68 U1 1 U2 9 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD MAR PY 2004 VL 17 IS 5 BP 906 EP 929 DI 10.1175/1520-0442(2004)017<0906:TRIOSA>2.0.CO;2 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 801RX UT WOS:000220114100004 ER PT J AU Randel, W Udelhofen, P Fleming, E Geller, M Gelman, M Hamilton, K Karoly, D Ortland, D Pawson, S Swinbank, R Wu, F Baldwin, M Chanin, ML Keckhut, P Labitzke, K Remsberg, E Simmons, A Wu, D AF Randel, W Udelhofen, P Fleming, E Geller, M Gelman, M Hamilton, K Karoly, D Ortland, D Pawson, S Swinbank, R Wu, F Baldwin, M Chanin, ML Keckhut, P Labitzke, K Remsberg, E Simmons, A Wu, D TI The SPARC intercomparison of middle-atmosphere climatologies SO JOURNAL OF CLIMATE LA English DT Article ID HALOGEN OCCULTATION EXPERIMENT; QUASI-BIENNIAL OSCILLATION; SEMIANNUAL OSCILLATION; STRATOSPHERIC ANALYSES; METEOROLOGICAL-OFFICE; TROPICAL STRATOSPHERE; TEMPERATURE PROFILES; GEOPOTENTIAL HEIGHT; RESEARCH SATELLITE; REANALYSIS AB An updated assessment of uncertainties in "observed" climatological winds and temperatures in the middle atmosphere (over altitudes similar to10-80 km) is provided by detailed intercomparisons of contemporary and historic datasets. These datasets include global meteorological analyses and assimilations, climatologies derived from research satellite measurements, historical reference atmosphere circulation statistics, rocketsonde wind and temperature data, and lidar temperature measurements. The comparisons focus on a few basic circulation statistics (temperatures and zonal winds), with special attention given to tropical variability. Notable differences are found between analyses for temperatures near the tropical tropopause and polar lower stratosphere, temperatures near the global stratopause, and zonal winds throughout the Tropics. Comparisons of historical reference atmosphere and rocketsonde temperatures with more recent global analyses show the influence of decadal-scale cooling of the stratosphere and mesosphere. Detailed comparisons of the tropical semiannual oscillation (SAO) and quasi-biennial oscillation (QBO) show large differences in amplitude between analyses; recent data assimilation schemes show the best agreement with equatorial radiosonde, rocket, and satellite data. C1 Natl Ctr Atmospher Res, Boulder, CO 80309 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Ctr Environm Predict, Washington, DC USA. Int Pacific Res Ctr, Honolulu, HI USA. Univ Oklahoma, Norman, OK 73019 USA. NW Res Associates Inc, Bellevue, WA 98009 USA. Met Off, Exeter, Devon, England. Serv Aeron, Paris, France. Free Univ Berlin, D-1000 Berlin, Germany. NASA, Langley Res Ctr, Hampton, VA 23665 USA. European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England. Jet Prop Lab, Pasadena, CA USA. RP Randel, W (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80309 USA. EM randel@ucar.edu RI Karoly, David/C-8262-2011; Baldwin, Mark/J-6720-2012; Wu, Dong/D-5375-2012; Pawson, Steven/I-1865-2014; Randel, William/K-3267-2016 OI Karoly, David/0000-0002-8671-2994; Pawson, Steven/0000-0003-0200-717X; Randel, William/0000-0002-5999-7162 NR 48 TC 135 Z9 136 U1 1 U2 16 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD MAR PY 2004 VL 17 IS 5 BP 986 EP 1003 DI 10.1175/1520-0442(2004)017<0986:TSIOMC>2.0.CO;2 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 801RX UT WOS:000220114100008 ER PT J AU Lin, B Wong, TM Wielicki, BA Hu, YX AF Lin, B Wong, TM Wielicki, BA Hu, YX TI Examination of the decadal tropical mean ERBS nonscanner radiation data for the iris hypothesis SO JOURNAL OF CLIMATE LA English DT Article ID INFRARED IRIS; FEEDBACK; EARTH AB Recent studies of the Earth Radiation Budget Satellite (ERBS) nonscanner radiation data indicate decadal changes in tropical cloudiness and unexpected radiative anomalies between the 1980s and 1990s. In this study, the ERBS decadal observations are compared with the predictions of the Iris hypothesis using 3.5-box model. To further understand the predictions, the tropical radiative properties observed from recent Clouds and the Earth's Radiant Energy System (CERES) radiation budget experiment [ the NASA Langley Research Center (LaRC) parameters] are used to replace the modeled values in the Iris hypothesis. The predicted variations of the radiation fields strongly depend on the relationship (-22% K-1) of tropical high cloud and sea surface temperature (SST) assumed by the Iris hypothesis. On the decadal time scale, the predicted tropical mean radiative flux anomalies are generally significantly different from those of the ERBS measurements, suggesting that the decadal ERBS nonscanner radiative energy budget measurements do not support the strong negative feedback of the Iris effect. Poor agreements between the satellite data and model predictions even when the tropical radiative properties from CERES observations (LaRC parameters) are used imply that besides the Iris-modeled tropical radiative properties, the unrealistic variations of tropical high cloud generated from the detrainment of deep convection with SST assumed by the Iris hypothesis are likely to be another major factor for causing the deviation between the predictions and observations. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Lin, B (reprint author), NASA, Langley Res Ctr, MS 420, Hampton, VA 23681 USA. EM b.lin@larc.nasa.gov RI Hu, Yongxiang/K-4426-2012 NR 13 TC 14 Z9 14 U1 1 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD MAR PY 2004 VL 17 IS 6 BP 1239 EP 1246 DI 10.1175/1520-0442(2004)017<1239:EOTDTM>2.0.CO;2 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806RD UT WOS:000220450100007 ER PT J AU Minschwaner, K Dessler, AE AF Minschwaner, K Dessler, AE TI Water vapor feedback in the tropical upper troposphere: Model results and observations SO JOURNAL OF CLIMATE LA English DT Article ID HALOGEN OCCULTATION EXPERIMENT; SEA-SURFACE TEMPERATURE; CLIMATE FEEDBACK; DEEP CONVECTION; EL-NINO; ICE-AGE; HUMIDITY; GREENHOUSE; SENSITIVITY; ATMOSPHERE AB The sensitivity of water vapor in the tropical upper troposphere to changes in surface temperature is examined using a single-column, radiative-convective model that includes couplings between the moistening effects of convective detrainment, the drying effects from clear-air subsidence, and radiative heating and cooling from water vapor. Equilibrium states of this model show that as the surface warms, changes in the vertical distribution and temperature of detraining air from tropical convection lead to higher water vapor mixing ratios in the upper troposphere. However, the increase in mixing ratio is not as large as the increase in saturation mixing ratio due to warmer environmental temperatures, so that relative humidity decreases. These changes in upper-tropospheric humidity with respect to surface temperature are consistent with observed interannual variations in relative humidity and water vapor mixing ratio near 215 mb as measured by the Microwave Limb Sounder and the Halogen Occultation Experiment. The analysis suggests that models that maintain a fixed relative humidity above 250 mb are likely overestimating the contribution made by these levels to the water vapor feedback. C1 New Mexico Inst Min & Technol, Dept Phys, Socorro, NM 87801 USA. Goddard Earth Sci & Technol Ctr, Baltimore, MD USA. Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. RP Minschwaner, K (reprint author), New Mexico Inst Min & Technol, Dept Phys, Socorro, NM 87801 USA. EM krm@kestrel.nmt.edu RI Dessler, Andrew/G-8852-2012 OI Dessler, Andrew/0000-0003-3939-4820 NR 47 TC 73 Z9 76 U1 1 U2 11 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD MAR PY 2004 VL 17 IS 6 BP 1272 EP 1282 DI 10.1175/1520-0442(2004)017<1272:WVFITT>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806RD UT WOS:000220450100010 ER PT J AU Negri, AJ Adler, RF Xu, LM Surratt, J AF Negri, AJ Adler, RF Xu, LM Surratt, J TI The impact of Amazonian deforestation on dry season rainfall SO JOURNAL OF CLIMATE LA English DT Article ID CLIMATE-CHANGE; PRECIPITATION; TRMM; ENHANCEMENT; CLOUDS; RADAR AB Many modeling studies have concluded that widespread deforestation of Amazonia would lead to decreased rainfall. Geosynchronous visible and infrared satellite data over southwest Brazil are analyzed with respect to percent cloudiness, and rain estimates are analyzed from both the Tropical Rainfall Measuring Mission and Special Sensor Microwave Imager. The studies conclude that in the dry season, when the effects of the surface are not overwhelmed by synoptic-scale weather disturbances, shallow cumulus cloudiness, deep convective cloudiness, and rainfall occurrence all are larger over the deforested and nonforested (savanna) regions than over areas of dense forest. This paper speculates that this difference is in response to a local circulation initiated by the differential heating of the region's varying forestation. Analysis of the diurnal cycle of cloudiness reveals a shift in the onset of convection toward afternoon hours in the deforested and toward the morning hours in the savanna regions when compared to the neighboring forested regions. Analysis of 14 years of monthly estimates from the Special Sensor Microwave Imager data revealed that in August there was a pattern of higher monthly rainfall amounts over the deforested region. Analysis of available rain gauge data showed an increase in regional rainfall since deforestation began around 1978. C1 NASA, Atmospheres Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA. N Carolina State Univ, Dept Marine Earth & Atmospher Sci, Raleigh, NC 27695 USA. RP Negri, AJ (reprint author), NASA, Atmospheres Lab, Goddard Space Flight Ctr, Code 912, Greenbelt, MD 20771 USA. EM negri@agnes.gsfc.nasa.gov RI Surratt, Jason/D-3611-2009 OI Surratt, Jason/0000-0002-6833-1450 NR 26 TC 63 Z9 64 U1 2 U2 16 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD MAR PY 2004 VL 17 IS 6 BP 1306 EP 1319 DI 10.1175/1520-0442(2004)017<1306:TIOADO>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806RD UT WOS:000220450100013 ER PT J AU Sohn, BJ Smith, EA Robertson, FR Park, SC AF Sohn, BJ Smith, EA Robertson, FR Park, SC TI Derived over-ocean water vapor transports from satellite-retrieved E-P datasets SO JOURNAL OF CLIMATE LA English DT Article ID ATMOSPHERIC MOISTURE; INTERANNUAL VARIABILITY; HYDROLOGICAL CYCLE; TROPICAL RAINFALL; ENERGY TRANSPORTS; UNITED-STATES; REANALYSES; CIRCULATION; CONVERGENCE; NCEP/NCAR AB A methodology is developed for deriving atmospheric water vapor transports over the World Oceans from satellite-retrieved precipitation (P) and evaporation (E) datasets. The motivation for developing the method is to understand climatically varying properties of transports, that is, year-to-year changes of the seasonally averaged divergent transport distribution fields, over regions where conventional data, in particular, winds, are sparse. Ultimately, the method is intended to take advantage of the relatively complete and consistent coverage, as well as continuity in sampling, associated with E 2 P datasets obtained from satellite measurements. Separate P and E retrievals from Special Sensor Microwave Imager (SSM/I) measurements, along with P retrievals from Tropical Rainfall Measuring Mission (TRMM) measurements, are used to obtain the transport solutions. In this opening study, a 7-yr climatological normal is derived for the January-February-March (JFM) period for years 1988-94, providing the basis for comparing vapor transport anomalies from the 1997/98 El Nino and 1999/2000 La Nina events. These are derived from JFM-averaged transport solutions for 1998 and 1999, respectively. These two periods correspond to times when the Multivariate ENSO Index (MEI) provided by the NOAA Climatic Data Center (CDC) was first at a relative maximum and then at a relative minimum in conjunction with back-to-back west Pacific warm and cold events. Because the El Nino-LaNina events produce such highly contrasting behavior in the transports, shifting from a largely meridionally oriented solution to a largely zonally oriented solution, focusing on this pairing, helps to explain why the methodology is reliable and effective in capturing important details embedded in full-coverage E 2 P fields. The analysis includes a sensitivity study of the transport solution technique based on 20 combinations of four precipitation datasets (two satellite based and two model based) and five evaporation datasets (two satellite based, one in situ observation based, and two model based), which helps to explain the reliability of the method. The analysis also includes a comparison to water vapor transports derived with the same method, but applied to E 2 P datasets obtained from global analysis products prepared by the National Centers of Environmental Prediction (NCEP), again to help explain the reliability of the method. The study concludes by first showing how the anomaly JFM 1998 El Nino solution behaves in close correspondence to associated SST anomalies and is generally more realistic in comparison to the corresponding NCEP solution. Finally, its reliability is discussed in terms of the implications of the vapor transport features for the El Nino-LaNina transition, vis-a-vis north south and east-west circulations and their accompanying impact on the atmospheric hydrological cycle. C1 Seoul Natl Univ, Sch Earth & Environm Sci, Seoul 151747, South Korea. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Global Hydrol & Climate Ctr, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Sohn, BJ (reprint author), Seoul Natl Univ, Sch Earth & Environm Sci, NS80, Seoul 151747, South Korea. EM sohn@snu.ac.kr RI Kim, Bo-Ra/E-6100-2013 NR 29 TC 19 Z9 19 U1 0 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD MAR PY 2004 VL 17 IS 6 BP 1352 EP 1365 DI 10.1175/1520-0442(2004)017<1352:DOWVTF>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 806RD UT WOS:000220450100016 ER PT J AU Brock, JC Krabill, WB Sallenger, AH AF Brock, JC Krabill, WB Sallenger, AH TI Barrier island morphodynamic classification based on lidar metrics for north Assateague Island, Maryland SO JOURNAL OF COASTAL RESEARCH LA English DT Article DE remote sensing; lidar; airborne topographic mapper; barrier islands; geomorphology; Assateague Island AB In order to reap the potential of airborne lidar surveys to provide geological information useful in understanding coastal sedimentary processes acting on various time scales, a new set of analysis methods are needed. This paper presents a multi-temporal lidar analysis of north Assateague Island, Maryland, and demonstrates the calculation of lidar metries that condense barrier island morphology and morphological change into attributed linear features that may be used to analyze trends in coastal evolution. The new methods proposed in this paper are also of significant practical value, because lidar metric analysis reduces large volumes of point elevations into linear features attributed with essential morphological variables that are ideally suited for inclusion in Geographic Information Systems. A morphodynamic classification of north Assategue Island for a recent 10 month time period that is based on the recognition of simple patterns described by lidar change metrics is presented. Such morphodynamic classification reveals the relative magnitude and the fine scale alongshore variation in the importance of coastal changes over the study area during a defined time period. More generally, through the presentation of this morphodynamic classification of north Assateague Island, the value of lidar metrics in both examining large lidar data sets for coherent trends and in building hypotheses regarding processes driving barrier evolution is demonstrated. C1 USGS, Ctr Coastal & Reg Marine Studies, St Petersburg, FL 33701 USA. NASA, Goddard Space Flight Ctr, Wallops Flight Facil, Wallops Isl, VA 23337 USA. RP Brock, JC (reprint author), USGS, Ctr Coastal & Reg Marine Studies, 600 4th St S, St Petersburg, FL 33701 USA. EM jbrock@usgs.gov; krabill@osb1.wff.nasa.gov NR 14 TC 8 Z9 8 U1 2 U2 15 PU COASTAL EDUCATION & RESEARCH FOUNDATION PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 USA SN 0749-0208 J9 J COASTAL RES JI J. Coast. Res. PD SPR PY 2004 VL 20 IS 2 BP 498 EP 509 DI 10.2112/1551-5036(2004)020[0498:BIMCBO]2.0.CO;2 PG 12 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA 841UI UT WOS:000222956700011 ER PT J AU Beran, MJ AF Beran, MJ TI Chimpanzees (Pan troglodytes) respond to nonvisible sets after one-by-one addition and removal of items SO JOURNAL OF COMPARATIVE PSYCHOLOGY LA English DT Article ID MONKEYS SAIMIRI-SCIUREUS; MACAQUES MACACA-MULATTA; AFRICAN GRAY PARROT; SQUIRREL-MONKEYS; NUMERICAL COMPETENCE; NUMBER REPRESENTATION; RHESUS-MONKEYS; PONGO-PYGMAEUS; DISCRIMINATION; FOOD AB Two chimpanzees (Pan troglodytes) made numerousness judgments of nonvisible sets of items. In Experiment 1, 1-10 items were dropped I at a time into an opaque cup, and then an additional 1-10 items were dropped I at a time into another opaque cup. The chimpanzees' performance levels were high and were more dependent on factors indicative of an analogue-magnitude mechanism for representation of set size than on an object file mechanism. In Experiment 2, a 3rd visible set was made available after the sequential presentation of the first 2 sets. The chimpanzees again performed at high levels in selecting the largest of the 3 sets. In Experiment 3, 1 of the 2 initially presented sets was reduced in number by the sequential removal of 1, 2, or 3 items. Both chimpanzees performed above chance levels for the removal of 1, but not more than 1, item. C1 Georgia State Univ, Langley Res Ctr, Decatur, GA USA. RP Beran, MJ (reprint author), Georgia State Univ, Langley Res Ctr, 3401 Panthersville Rd, Decatur, GA USA. EM mjberan@yahoo.com RI Beran, Michael/M-8743-2016 OI Beran, Michael/0000-0002-2504-0338 FU NICHD NIH HHS [HD-38051] NR 75 TC 96 Z9 97 U1 8 U2 11 PU AMER PSYCHOLOGICAL ASSOC PI WASHINGTON PA 750 FIRST ST NE, WASHINGTON, DC 20002-4242 USA SN 0735-7036 J9 J COMP PSYCHOL JI J. Comp. Psychol. PD MAR PY 2004 VL 118 IS 1 BP 25 EP 36 DI 10.1037/0735-7036.118.1.25 PG 12 WC Behavioral Sciences; Psychology; Psychology, Multidisciplinary; Zoology SC Behavioral Sciences; Psychology; Zoology GA 803JH UT WOS:000220226900004 PM 15008670 ER PT J AU Wang, ZJ Zhang, LP Liu, Y AF Wang, ZJ Zhang, LP Liu, Y TI Spectral (finite) volume method for conservation laws on unstructured grids IV: extension to two-dimensional systems SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE high-order; unstructured grid; spectral volume; 2D systems of conservation laws; Euler equations ID ESSENTIALLY NONOSCILLATORY SCHEMES; ONE-DIMENSIONAL SYSTEMS; ELEMENT METHOD; IMPLEMENTATION; TRIANGLE; MESHES; FLOW AB In this paper, the fourth in a series, the spectral volume (SV) method is extended to multi-dimensional systems-the 2D Euler equations. The focus of this paper is to study the performance of the SV method on multidimensional non-linear systems, and to verify that high order solution accuracy up to fourth-order can be achieved for the systems of conservation laws. Implementation details including total variation diminishing (TVD) and total variation bounded (TVB) limiters are presented. An accuracy study is performed first to numerically verify that the designed order of accuracy can be obtained for smooth flow solutions. Then, solutions with both smooth features and discontinuities are utilized to demonstrate the overall capability of the SV method. (C) 2003 Elsevier Inc. All rights reserved. C1 Michigan State Univ, Dept Mech Engn, E Lansing, MI 48824 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Wang, ZJ (reprint author), Michigan State Univ, Dept Mech Engn, 2555 Engn Bldg, E Lansing, MI 48824 USA. EM zjw@egr.msu.edu; liu@nas.nasa.gov RI Wang, Z.J./A-9628-2010 OI Wang, Z.J./0000-0002-6203-6303 NR 26 TC 113 Z9 116 U1 0 U2 5 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAR 1 PY 2004 VL 194 IS 2 BP 716 EP 741 DI 10.1016/j.jcp.2003.09.012 PG 26 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 800LO UT WOS:000220030000015 ER PT J AU Yesilyurt, S Motakef, S Grugel, R Mazuruk, K AF Yesilyurt, S Motakef, S Grugel, R Mazuruk, K TI The effect of the traveling magnetic field (TMF) on the buoyancy-induced convection in the vertical Bridgman growth of semiconductors SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE material processing; traveling magnetic field; microgravity; vertical Bridgman technique ID CRYSTAL-GROWTH AB A traveling magnetic field (TMF) is created by means of applying out-of-phase currents to a number of coils. When applied to a conducting melt inside a cylindrical container, the TMF induces a Lorentz force that acts in the meridional directions (radial and axial), unlike the application of a rotating magnetic field (RMF), which creates a force in the azimuthal direction. In this work, we present a computational study of the TMF and its application to the Bridgman growth of the Ge. To quantify the effect of the TMF on the solid-melt interface, we use the maximum (magnitude-wise) tangential shear at the interface. (C) 2003 Elsevier B.V. All rights reserved. C1 Sabanci Univ, Istanbul, Turkey. Cape Simulat, Natick, MA USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Yesilyurt, S (reprint author), Sabanci Univ, Istanbul, Turkey. EM syesilyurt@sabanciuniv.edu RI Yesilyurt, Serhat/H-9546-2013 OI Yesilyurt, Serhat/0000-0001-5425-1532 NR 9 TC 38 Z9 39 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR 1 PY 2004 VL 263 IS 1-4 BP 80 EP 89 DI 10.1016/j.jcrysgro.2003.11.066 PG 10 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 802SY UT WOS:000220184400014 ER PT J AU Sogard, SM Spencer, ML AF Sogard, SM Spencer, ML TI Energy allocation in juvenile sablefish: effects of temperature, ration and body size SO JOURNAL OF FISH BIOLOGY LA English DT Article DE bioenergetics; growth; lipid storage; trade-offs ID ANOPLOPOMA-FIMBRIA; PROXIMATE COMPOSITION; COMPENSATORY GROWTH; SEASONAL-VARIATION; WATER TEMPERATURE; SALMON; SURVIVAL; RESPONSES; MORTALITY; LARVAL AB The lipid deposition of juvenile sablefish Anoplopoma fimbria was examined, in particular, the charges in allocation over time. Growth rates of early juveniles (initial size 36-50 ram total length, L-T) were manipulated using two temperatures (10 and 20degreesC) and two rations (ad libitum and 3-4% body mass day(-1)). Fish L-T, mass and lipid content were measured every 3 weeks for 15 weeks. Irrespective of treatment. the relationship of total lipid content with body size was clearly hyperallometric; small juveniles allocated relatively more energy to growth and less to lipid storage than large juveniles. After adjusting for the influence of body size, temperature and ration significantly influenced body composition but these effects varied over the course of the experiment. In the first 3 week time period, fish on the high ration, high temperature treatment had reduced lipid storage relative to other treatments, but in all subsequent time periods their lipid concentrations were similar to or higher than those of fish on other treatments. In contrast, fish held at low rations and low temperatures initially had average levels of lipid concentration, but after 6 weeks their levels were lower than other treatments. Estimation of allocation to lipid storage over time (proportion of dry mass increase comprised of lipid) suggested that fish in all of the treatments were approaching an asymptotic level of lipid concentration (c. 50-60% of dry mass) but with different rates of lipid increase. Within a treatment, it was predicted that individual differences in allocation would result in trade-offs between somatic growth and storage. This trade-off was evident only for fish held on low rations at low temperatures. In contrast, fish held on high rations at high temperatures exhibited the opposite pattern of a positive correlation between somatic growth and storage. These results suggest that lipostatic regulation of appetite is unlikely in juvenile sablefish. When resources are unlimited, this species appears to adopt a maximizing strategy for both somatic growth and lipid accumulation. (C) 2004 The Fisheries Society of the British Isles. C1 Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Newport, OR 97365 USA. RP Sogard, SM (reprint author), Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, 110 Shaffer Rd, Santa Cruz, CA 95060 USA. EM susan.sogard@noaa.gov NR 30 TC 34 Z9 36 U1 0 U2 16 PU BLACKWELL PUBLISHING LTD PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND SN 0022-1112 J9 J FISH BIOL JI J. Fish Biol. PD MAR PY 2004 VL 64 IS 3 BP 726 EP 738 DI 10.1046/j.1095-8649.2004.00342.x PG 13 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 801MK UT WOS:000220099800014 ER PT J AU Brear, MJ Warfield, Z Mangus, JF Braddom, S Paduano, JS Philhower, JS AF Brear, MJ Warfield, Z Mangus, JF Braddom, S Paduano, JS Philhower, JS TI Flow separation within the engine inlet of an uninhabited combat air vehicle (UCAV) SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID PRESSURE SURFACE SEPARATIONS; TURBINES AB This paper discusses the structure of the flow within the engine inlet of an uninhabited Combat air vehicle (UCAV). The UCAV features a top-mounted, serpentine inlet leading to an engine buried within the fuselage. The performance of the inlet is found to depend strongly on a flow separation that occurs within the inlet. Both the time-averaged and the unsteady structure of this separation is studied, and an argument relating the inlet perjormance to the behavior of this separation is suggested. The results presented in this paper also suggest that there are considerable aerodynamic limitations to further shortening or narrowing of the inlet. Since there arc substantial, system level benefits from using a smaller inlet, the case for separated flow control therefore appears clear. C1 Univ Melbourne, Dept Mech & Mfg Engn, Parkville, Vic 3052, Australia. Jet Prop Lab, Mech Engn Sect, Struct & Configurat Grp, Pasadena, CA USA. Northrop Grumman Corp, Integrated Syst, Chandler, AZ USA. MIT, Gas Turbine Lab, Cambridge, MA 02139 USA. RP Brear, MJ (reprint author), Univ Melbourne, Dept Mech & Mfg Engn, Parkville, Vic 3052, Australia. EM mjbrear@unimelb.edu.au NR 16 TC 2 Z9 5 U1 1 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD MAR PY 2004 VL 126 IS 2 BP 266 EP 272 DI 10.1115/1.1667885 PG 7 WC Engineering, Mechanical SC Engineering GA 817BO UT WOS:000221153200019 ER PT J AU Gende, SM Quinn, TP Willson, MF Heintz, R Scott, TM AF Gende, SM Quinn, TP Willson, MF Heintz, R Scott, TM TI Magnitude and fate of salmon-derived nutrients and energy in a coastal stream ecosystem SO JOURNAL OF FRESHWATER ECOLOGY LA English DT Article ID ONCORHYNCHUS-KISUTCH CARCASSES; BEARS URSUS-ARCTOS; SOCKEYE-SALMON; PACIFIC SALMON; BROWN BEARS; COHO SALMON; TERRESTRIAL ECOSYSTEMS; SOUTHEAST ALASKA; PRODUCTIVITY; NITROGEN AB We quantified the energy and mineral (nitrogen, phosphorous) composition of live pink salmon (Oncorhynchus gorbuscha) and chum salmon (O. keta), their eggs, and carcasses, and tracked the fate of chum salmon spawning in a small Alaskan coastal stream. On average, salmon entered streams with 5.3 kJ.g(-1), 3.3% N, 0.48% P. Much of the energy in female salmon was stored in the gametes because the gonads were both large (20% of their wet body mass) and high in energy density (11 kJ/g). Carcasses following senescent death had lower mass-specific energy and N (but not P) compared to fish at stream entrance. Bears removed nearly 50% of the salmon-derived nutrients and energy from the stream by capturing salmon and dragging the carcasses from the stream. Much of the salmon biomass was made available to riparian scavengers because bears partially consumed the fish. Nutrients bound in salmon tissue at senescent death were quickly exported to the estuary after only a few days because of periodic high flows and low rates of scavenging by bears. C1 Pacific NW Res Stn, Juneau, AK 99801 USA. Univ Washington, Sch Aquat & Fishery Sci, Seattle, WA 98195 USA. Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. NW Fisheries Sci Ctr, Seattle, WA 98112 USA. RP Gende, SM (reprint author), Natl Pk Serv, Galcier Bay Field Stn, 3100 Natl Pk Rd, Juneau, AK 99801 USA. EM Scott_Gende@nps.gov NR 45 TC 51 Z9 52 U1 3 U2 25 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 0270-5060 EI 2156-6941 J9 J FRESHWATER ECOL JI J. Freshw. Ecol. PD MAR PY 2004 VL 19 IS 1 BP 149 EP 160 DI 10.1080/02705060.2004.9664522 PG 12 WC Ecology; Limnology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 779WM UT WOS:000189324900018 ER PT J AU Grenon, SM Sheynberg, N Xiao, X Ramsdell, CD Hurwitz, S Mai, CL Kim, C Cohen, RJ Williams, GH AF Grenon, SM Sheynberg, N Xiao, X Ramsdell, CD Hurwitz, S Mai, CL Kim, C Cohen, RJ Williams, GH TI A new model for the role of individual predisposition in orthostatic intolerance before and after exposure to simulated microgravity. SO JOURNAL OF INVESTIGATIVE MEDICINE LA English DT Meeting Abstract CT Combined Annual Meeting of the Central-Society-for-Clinical-Research/Midwestern Section of the American-Federation-for-Medical-Research CY APR 15, 2004 CL Chicago, IL SP Cent Soc Clin Res, Amer Federat Med Res, Midwest Sect C1 Brigham & Womens Hosp, Div Endocrinol Hypertens & Diabet, Boston, MA 02115 USA. McGill Univ, Dept Cardiothorac Surg, Montreal, PQ H3A 2T5, Canada. MIT, NASA, Ctr Quantitat Cardiovasc Physiol Modeling & Data, Harvard MIT Div Hlth Sci & Technol, Cambridge, MA 02139 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU B C DECKER INC PI HAMILTON PA 20 HUGHSON ST SOUTH, PO BOX 620, L C D 1, HAMILTON, ONTARIO L8N 3K7, CANADA SN 1081-5589 J9 J INVEST MED JI J. Invest. Med. PD MAR PY 2004 VL 52 IS 2 BP S384 EP S385 PG 2 WC Medicine, General & Internal; Medicine, Research & Experimental SC General & Internal Medicine; Research & Experimental Medicine GA 806EH UT WOS:000220416700135 ER PT J AU Penanen, K Hoffmann, JA Davis, JC Packard, RE AF Penanen, K Hoffmann, JA Davis, JC Packard, RE TI Effect of He-3 on third sound attenuation in thick He-4 films SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE third sound; helium film; quantized vortices ID SUPERFLUID-HELIUM FILMS; PERSISTENT CURRENTS; THIRD SOUND; MIXTURE FILMS; DECAY AB We have performed measurements of third sound attenuation in thick films of superfluid He-4 in the presence of small amounts of He-3. The attenuation due to He-3 appears to depend linearly on the number density of He-3 atoms in the film. We discuss the results in context of a recently proposed mechanism where the attenuation is caused by the interaction of the excitations in helium with the trapped vortices. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Cornell Univ, Dept Phys, LASSP, Ithaca, NY 14853 USA. RP Penanen, K (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM Konstantin.Penanen@jpl.nasa.gov NR 15 TC 1 Z9 1 U1 0 U2 2 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD JAN PY 2004 VL 134 IS 5-6 BP 1069 EP 1077 DI 10.1023/B:JOLT.0000016730.44519.37 PG 9 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 775ML UT WOS:000189044700004 ER PT J AU Elmustafa, AA Ananda, AA Elmahboub, WM AF Elmustafa, AA Ananda, AA Elmahboub, WM TI Dislocation mechanics simulations of the bilinear behavior in micro- and nanoindentation SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID STRAIN GRADIENT PLASTICITY; TO-DUCTILE TRANSITION; SINGLE-CRYSTALS; FINITE TEMPERATURES; STRESS-FIELD; DEFORMATION; HARDNESS; COPPER; MICROSTRUCTURE; METALS AB The hardnesses of electropolished, polycrystalline alpha-brass, and aluminum were measured as functions of load using Vickers microindentation, and Berkovich nanoindentation. Data were compared with literature data for silver, copper, and tungsten. In all cases, the hardness was observed to increase with decreasing size. Theories in the literature based on strain gradient plasticity and the addition of statistically stored and geometrically stored dislocation densities predict that the square of the hardness should increase linearly with inverse size of the indent. Our data and the literature data agree with this prediction over a limited range of indent diameters represented by microhardness and deep nanohardness data, whereas for the shallow nanohardness data, a second linear behavior is observed. The linear behavior of the microhardness and deep nanohardness data together with the second linear behavior generated by the shallow nanohardness data constituted what we designate a bilinear behavior. An algorithm is developed to calculate the induced shear stresses in a circular Volterra dislocation loop from a line integral of the Peach-Koehler equation using dislocation mechanics and isotropic elasticity. The computed induced shear stresses when plotted versus depth of indentation produced curves that exhibited a bilinear behavior identical to the bilinear behavior resulted from experiments, and the curves collapsed to a single curve for the different materials simulated. C1 NASA, Langley Res Ctr, CONITS, Hampton, VA 23681 USA. Hampton Univ, Dept Math, Hampton, VA 23668 USA. RP Elmustafa, AA (reprint author), NASA, Langley Res Ctr, CONITS, Hampton, VA 23681 USA. EM a.a.elmustafa@larc.nasa.gov NR 44 TC 5 Z9 5 U1 0 U2 3 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0884-2914 EI 2044-5326 J9 J MATER RES JI J. Mater. Res. PD MAR PY 2004 VL 19 IS 3 BP 768 EP 779 DI 10.1557/jmr.2004.19.3.768 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 833DJ UT WOS:000222316300014 ER PT J AU La Duc, MT Satomi, M Agata, N Venkateswaran, K AF La Duc, MT Satomi, M Agata, N Venkateswaran, K TI GyrB as a phylogenetic discriminator for members of the Bacillus anthracis-cereus-thuringiensis group SO JOURNAL OF MICROBIOLOGICAL METHODS LA English DT Article DE Bacillus; gvrB; phylogeny; discrimination ID RIBOSOMAL-RNA SEQUENCES; ENTEROTOXIN COMPLEX; GROUP BACTERIA; STRAINS; PCR; DIFFERENTIATION; IDENTIFICATION; OUTBREAK; CLONING AB Bacillus anthracis, the causative agent of the human disease anthrax, Bacillus cereus, a food-borne pathogen capable of causing human illness, and Bacillus thuringiensis, a well-characterized insecticidal toxin producer, all cluster together within a very tight clade (B. cereus group) phylogenetically and are indistinguishable from one another via 16S rDNA sequence analysis. As new pathogens are continually emerging, it is imperative to devise a system capable of rapidly and accurately differentiating closely related, yet phenotypically distinct species. Although the gyrB gene has proven useful in discriminating closely related species, its sequence analysis has not yet been validated by DNA:DNA hybridization, the taxonomically accepted "gold standard". We phylogenetically characterized the gyrB sequences of various species and serotypes encompassed in the "B. cereus group," including lab strains and environmental isolates. Results were compared to those obtained from analyses of phenotypic characteristics, 16S rDNA sequence, DNA:DNA hybridization, and virulence factors. The gyrB gene proved more highly differential than 16S, while, at the same time, as analytical as costly and laborious DNA:DNA hybridization techniques in differentiating species within the B. cereus group. (C) 2003 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Biotechnol & Planetary Protect Grp, Pasadena, CA 91109 USA. Natl Res Inst Fisheries, Div Food Proc, Yokohama, Kanagawa 2368648, Japan. Nagoya Publ Hlth Res Inst, Nagoya, Aichi, Japan. RP La Duc, MT (reprint author), CALTECH, Jet Prop Lab, Biotechnol & Planetary Protect Grp, 4800 Oak Grove Dr,Mail Stop 89, Pasadena, CA 91109 USA. EM mtladuc@jpl.nasa.gov NR 34 TC 64 Z9 67 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-7012 J9 J MICROBIOL METH JI J. Microbiol. Methods PD MAR PY 2004 VL 56 IS 3 BP 383 EP 394 DI 10.1016/j.mimet.2003.11.004 PG 12 WC Biochemical Research Methods; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA 777ZP UT WOS:000189214600010 PM 14967230 ER PT J AU Lepere, M Gobeille, R Kolodziejski, N Devi, VM Benner, DC Smith, MAH McMichael, W Aoaeh, B Wilkinson, K Mantz, AW AF Lepere, M Gobeille, R Kolodziejski, N Devi, VM Benner, DC Smith, MAH McMichael, W Aoaeh, B Wilkinson, K Mantz, AW TI Analysis of tunable diode-laser spectra of (R)Q(J,0) lines in CH3F near 1475 cm(-1) using a multispectrum fitting technique SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID NU(5) BANDS; NU(2); INTENSITIES; SELF; LINESTRENGTH; (CH3F)-C-12 AB We have analyzed the methyl fluoride (R)Q(J,0) Q branch lines located near 1475 cm(-1) using a simultaneous multi-spectrum fitting technique. In this analysis we have used previously recorded diode-laser data in which we collected many data points covering only one or two Q branch lines in a particular run. The analysis consists of simultaneously fitting 57 spectra collected with numerous pressure and path length conditions for all absorption lines. The data are concatenated to create one continuous spectrum of the Q branch. We have determined the intensity and self-broadened widths at 296 K for 23 (R)Q(J,0) lines. (C) 2003 Elsevier Inc. All rights reserved. C1 Connecticut Coll, Dept Phys Astron & Geophys, New London, CT 06320 USA. Fac Univ Notre Dame Paix, Lab Spect Mol, B-5000 Namur, Belgium. Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Mantz, AW (reprint author), Connecticut Coll, Dept Phys Astron & Geophys, 270 Mohegan Ave, New London, CT 06320 USA. EM awman@conncoll.edu OI Wilkinson, Kevin/0000-0002-4560-0718 NR 13 TC 2 Z9 2 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD MAR PY 2004 VL 224 IS 1 BP 7 EP 12 DI 10.1016/j.jms.2003.12.002 PG 6 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 777BY UT WOS:000189155300002 ER PT J AU Fukumori, I Lee, T Cheng, B Menemenlis, D AF Fukumori, I Lee, T Cheng, B Menemenlis, D TI The origin, pathway, and destination of Nino-3 water estimated by a simulated passive tracer and its adjoint SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID EQUATORIAL PACIFIC-OCEAN; NORTH PACIFIC; TROPICAL PACIFIC; EL-NINO; ENVIRONMENTAL PREDICTION; CIRCULATION MODEL; THERMOCLINE WATER; NATIONAL CENTERS; TRITIUM MAXIMUM; EXCHANGE AB The nature of subtropical - tropical water mass exchange in the Pacific Ocean is investigated, focusing on the origin, pathway, and destination of water occupying the surface layer of the eastern equatorial Pacific Ocean (Nino-3 region; 5degreesS - 5degreesN, 150degrees - 90degreesW). Simulated passive tracers and their adjoint are employed to explicitly follow the circulation of specific water masses accounting for advective and diffusive effects and their time variabilities. The evolution of the forward passive tracer and adjoint passive tracer can be identified as describing where the tracer-tagged water mass goes and from where it comes, respectively. Over 10 years on average, water mass of the Nino-3 region can be traced back to eastern subtropical thermocline waters of the Northern (27%) and Southern Hemispheres (39%). The Nino-3 water subsequently returns to these subtropical latitudes in the upper ocean. In contrast to the hypothesized "subtropical cell,'' however, this circulation is an open circuit with water returning to the western regions of the two hemispheres ( subtropical gyres) and to the Indian Ocean, instead of returning to its origins. The representative transit time scale from the subtropics to the Tropics is 10 15 yr. Temporal variability causes the tropical circulation inferred from a time-mean state to differ significantly from the average circulation. In particular, stirring due to nonseasonal, intra-annual variability significantly enhances the transport magnitude of the so-called interior pathways relative to that of the circuitous low-latitude western boundary pathways. Such short-circuit in the subtropical - tropical exchange may help better to explain tracer distributions, such as the observed midbasin tritium maximum in the equatorial Pacific Ocean. Significant differences in circulation pathways are also identified that are associated with El Nino and La Nina events. The strength of the subtropical - tropical water mass exchange is estimated to have weakened during the 1990s. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Fukumori, I (reprint author), CALTECH, Jet Prop Lab, Mail Stop 300-323,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM fukumori@jpl.nasa.gov NR 47 TC 68 Z9 69 U1 2 U2 9 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD MAR PY 2004 VL 34 IS 3 BP 582 EP 604 DI 10.1175/2515.1 PG 23 WC Oceanography SC Oceanography GA 807CG UT WOS:000220479000004 ER PT J AU Mulenburg, GM AF Mulenburg, GM TI The project management office toolkit: A step-by-step guide to setting up a project management office SO JOURNAL OF PRODUCT INNOVATION MANAGEMENT LA English DT Book Review C1 Natl Aeronaut & Space Adm, Washington, DC 20546 USA. RP Mulenburg, GM (reprint author), Natl Aeronaut & Space Adm, Washington, DC 20546 USA. NR 1 TC 0 Z9 0 U1 0 U2 9 PU BLACKWELL PUBLISHERS PI MALDEN PA 350 MAIN STREET, STE 6, MALDEN, MA 02148 USA SN 0737-6782 J9 J PROD INNOVAT MANAG JI J. Prod. Innov. Manage. PD MAR PY 2004 VL 21 IS 2 BP 151 EP 152 DI 10.1111/j.0737-6782.2004.064_2.x PG 2 WC Business; Engineering, Industrial; Management SC Business & Economics; Engineering GA 809VQ UT WOS:000220664600006 ER PT J AU Gatsonis, NA Zwahlen, J Wheelock, A Pencil, EJ Kamhawi, H AF Gatsonis, NA Zwahlen, J Wheelock, A Pencil, EJ Kamhawi, H TI Pulsed plasma thruster plume investigation using a current-mode quadruple probe method SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA/ASME/SAE/ASEE 38th Joint Propulsion Conference CY JUL 07-10, 2002 CL INDIANAPOLIS, INDIANA SP Amer Inst Aeronaut & Astronaut, ASME, SAE, ASEE ID ELECTROSTATIC PROBES; LANGMUIR PROBE; VELOCITY; COLLISIONLESS AB A current-mode quadruple-Langmuir-probe method was developed and used to measure electron temperature, electron density, and the ratio of ion speed to most probable thermal speed in the plume of a rectangular-plate laboratory model Teflon(R) pulsed plasma thruster. The current mode involves biasing all the electrodes and measuring the collected currents. The current collection theory and uncertainty analysis are presented. The thruster was operating at discharge energies of 5, 20, and 40 J and 15-microsecond pulses. Quadruple-probe measurements were taken at 10, 15, and 20 cm downstream of the Teflon propellant surface and angular locations of up to 40 deg off the centerline on planes perpendicular and parallel to the thruster electrodes. The electron temperature at 10 cm reaches values that range from 10 to 18 eV during the rise of the discharge current but remains below 5 eV for the rest of the pulse. The electron temperature shows no angular variation but reduces with increasing radial distance. The maximum electron density at 10 cm is 10,(20) 7 x 10,(20) and 1.5 x 10(21) m(-3) for the 5, 20, and 40-j discharge energy, respectively. The electron density reduces with increasing angle especially at larger downstream distances. The ion-speed ratios indicate supersonic ions and increase with downstream distance and for all angles considered. Ion speeds at 10 cm are approximately 30,000 rats at the beginning of the pulse and reduce in magnitude to below 10,000 rats near the end of the pulse. C1 Worcester Polytech Inst, Worcester, MA 01609 USA. NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. RP Gatsonis, NA (reprint author), Worcester Polytech Inst, Worcester, MA 01609 USA. EM gatsonis@wpi.edu NR 39 TC 7 Z9 10 U1 1 U2 6 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 2004 VL 20 IS 2 BP 243 EP 254 DI 10.2514/1.1753 PG 12 WC Engineering, Aerospace SC Engineering GA 805MB UT WOS:000220369300006 ER PT J AU Smart, MK Trexler, CA AF Smart, MK Trexler, CA TI Mach 4 performance of hypersonic inlet with rectangular-to-elliptical shape transition SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT 41st Aerospace Sciences Meeting CY JAN 06-09, 2003 CL RENO, NEVADA AB Wind-tunnel testing of a hypersonic inlet with rectangular-to-elliptical shape transition has been conducted at Mach 4.0. This fixed geometry inlet had a geometric contraction ratio of 4.8 and was designed using a quasi-streamline tracing technique to have a design point of Mach 5.7. These tests were performed to investigate the starting and backpressure limits of the inlet at conditions well below its design point. Results showed that the inlet required side spillage holes in order to self-start at Mach 4.0. Once started, the inlet generated a compression ratio of 12.6, captured almost 80% of available air and withstood a backpressure ratio of 30.3 relative to tunnel static pressure. The spillage penalty for self-starting was estimated to be 3.4% of available air. These experimental results, along with previous experimental results at Mach 6.2, indicate that fixed-geometry inlets with rectangular-to-elliptical shape transition are a viable configuration for airframe-integrated scramjets that operate over a significant Mach-number range. C1 NASA Langley Res Ctr, Hyperson Airbreathing Propuls Branch, Hampton, VA 23681 USA. RP Smart, MK (reprint author), NASA Langley Res Ctr, Hyperson Airbreathing Propuls Branch, Hampton, VA 23681 USA. RI Smart, Michael/C-8823-2013 NR 10 TC 14 Z9 18 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 2004 VL 20 IS 2 BP 288 EP 293 DI 10.2514/1.1296 PG 6 WC Engineering, Aerospace SC Engineering GA 805MB UT WOS:000220369300011 ER PT J AU Lattime, SB Steinetz, BM AF Lattime, SB Steinetz, BM TI High-pressure-turbine clearance control systems: Current practices and future directions SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB Improved blade-tip sealing in a high-pressure compressor and high-pressure turbine can provide dramatic improvements in specific fuel consumption, time on wing, compressor stall margin, and engine efficiency as well as increased payload and mission range capabilities. Maintenance costs to overhaul large commercial gas turbine engines can easily exceed $1 million. Removal of engines from service is primarily due to the spent exhaust gas temperature margin caused mainly by the deterioration of high-pressure-turbine components. Increased blade-tip clearance is a major factor in hot-section component degradation. As engine designs continue to push the performance envelope with fewer parts and the market drives manufacturers to increase service life, the need for advanced sealing continues to grow. A review of aero-gas-turbine engine high-pressure-turbine performance degradation and the mechanisms that promote these losses are presented. Benefits to the high-pressure turbine due to improved clearance management are identified. Past and present sealing technologies are presented along with specifications for next-generation engine clearance control systems. C1 Ohio Aerosp Inst, NASA Glenn Res Ctr, Cleveland, OH 44142 USA. NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. RP Lattime, SB (reprint author), Ohio Aerosp Inst, NASA Glenn Res Ctr, MS 23-3,21000 Brookpk Rd, Cleveland, OH 44142 USA. NR 23 TC 52 Z9 73 U1 3 U2 15 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 2004 VL 20 IS 2 BP 302 EP 311 DI 10.2514/1.9255 PG 10 WC Engineering, Aerospace SC Engineering GA 805MB UT WOS:000220369300013 ER PT J AU Proctor, MP Kumar, A Delgado, IR AF Proctor, MP Kumar, A Delgado, IR TI High-speed, high-temperature finger seal test results SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB A pressure balanced finger seal was tested in NASA's High-Temperature, High-Speed Turbine Seal Test Rig at conditions up to 922 K, 366 m/s, and 517 kPa to study its leakage, power loss, and wear performance at advanced engine conditions. Static, performance, endurance, and postperformance tests were conducted. The finger seal leakage performance met the flow factor goal of 7.72 kg-rootK/MPa-m-s during the endurance test, which simulated expected advanced-engine rated power conditions. The maximum finger seal power loss of 10.4 kW occurred at 366 m/s and 517 kPa across the seal. Further design improvements are needed to reduce seal power loss. Finger seal power loss is comparable to measured brush seal power loss. Most finger seal wear occurred in the initial performance test and the accumulative seal weight loss leveled out over time. With approximately one-half the finger pad thickness remaining after 11 h of testing, the rate of seal wear is acceptable. Furthermore, the high velocity oxygen fuel thermally sprayed (HVOF) chrome carbide coating on the rotor performed well, with a final wear track depth less than 6.35 mum. The finger seal is very sensitive to clearance, and further testing is required to separate and,quantify the effects of changes in radial clearance from apparent hysteresis. C1 NASA, Lewis Res Ctr, Mech Components Branch, US Army Res Lab, Cleveland, OH 44135 USA. Honeywell Engines, Syst & Serv, Phoenix, AZ 85034 USA. RP Proctor, MP (reprint author), NASA, Lewis Res Ctr, Mech Components Branch, US Army Res Lab, Lewis Field, Cleveland, OH 44135 USA. NR 9 TC 10 Z9 12 U1 0 U2 10 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 2004 VL 20 IS 2 BP 312 EP 318 DI 10.2514/1.9256 PG 7 WC Engineering, Aerospace SC Engineering GA 805MB UT WOS:000220369300014 ER PT J AU Jiang, YB Yung, YL Sander, SP Travis, LD AF Jiang, YB Yung, YL Sander, SP Travis, LD TI Modeling of atmospheric radiative transfer with polarization and its application to the remote sensing of tropospheric ozone SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article AB Light reflected or transmitted by a planetary atmosphere contains information about particles and molecules in the atmosphere. Therefore, accurate modeling of the radiation field may be used to retrieve information on atmospheric composition. In this paper, a multi-layer model for a vertically inhomogeneous atmosphere is implemented by using the doubling-adding method for a plane-parallel atmosphere. By studying the degree of linear polarization of the transmitted and reflected solar light in the Huggins bands, we find significant differences between tropospheric ozone and stratospheric ozone. The effects of tropospheric ozone change on the linear polarization are 10 times more than that of the same amount of stratospheric ozone change. We also show the aerosol effect on the linear polarization, but this effect is wavelength independent as compared to that caused by the tropospheric ozone change. The results provide a theoretical basis for the retrieval of tropospheric ozone from measurement of linear polarization of the scattered sunlight both from the ground and from a satellite. (C) 2003 Elsevier Ltd. All rights reserved. C1 CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Div Earth & Space Sci, Pasadena, CA 91109 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Yung, YL (reprint author), CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. EM yly@mercu1.gps.caltech.edu NR 12 TC 8 Z9 8 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD MAR 1 PY 2004 VL 84 IS 2 BP 169 EP 179 DI 10.1016/S0022-4073(03)00140-7 PG 11 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 766LX UT WOS:000188378800004 ER PT J AU De Angelis, G Anderson, BM Atwell, W Nealy, JE Qualls, GD Wilson, JW AF De Angelis, G Anderson, BM Atwell, W Nealy, JE Qualls, GD Wilson, JW TI Astronaut EVA exposure estimates from CAD model spacesuit geometry SO JOURNAL OF RADIATION RESEARCH LA English DT Article DE space radiation; EVA; LEO; ISS; radiation safety; modeling AB Ongoing assembly and maintenance activities at the International Space Station (ISS) require much more extravehicular activity (EVA) than did the earlier U.S. Space Shuttle missions. It is thus desirable to determine and analyze, and possibly foresee, as accurately as possible what radiation exposures crew members involved in EVAs will experience in order to minimize risks and to establish exposure limits that must not to be exceeded. A detailed CAD model of the U.S. Space Shuttle EVA Spacesuit, developed at NASA Langley Research Center (LaRC), is used to represent the directional shielding of an astronaut; it has detailed helmet and backpack structures, hard upper torso, and multilayer space suit fabric material. The NASA Computerized Anatomical Male and Female (CAM and CAF) models are used in conjunction with the space suit CAD model for dose evaluation within the human body. The particle environments are taken from the orbit-averaged NASA AP8 and AE8 models at solar cycle maxima and minima. The transport of energetic particles through space suit materials and body tissue is calculated by using the NASA LaRC HZETRN code for hadrons and a recently developed deterministic transport code, ELTRN, for electrons. The doses within the CAM and CAF models are determined from energy deposition at given target points along 968 directional rays convergent on the points and are evaluated for several points on the skin and within the body. Dosimetric quantities include contributions from primary protons, light ions, and electrons, as well as from secondary brehmsstrahlung and target fragments. Directional dose patterns are displayed as rays and on spherical surfaces by the use of a color relative intensity representation. C1 Old Dominion Univ, Norfolk, VA 23508 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Ist Super Sanita, I-00161 Rome, Italy. Swales Aerosp Corp, Hampton, VA 23681 USA. Boeing Co, Houston, TX 77058 USA. RP De Angelis, G (reprint author), Old Dominion Univ, Norfolk, VA 23508 USA. EM g.deangelis@larc.nasa.gov NR 26 TC 6 Z9 6 U1 0 U2 6 PU JAPAN RADIATION RESEARCH SOC PI CHIBA PA C/O NAT INST RADIOLOGICAL SCI 9-1 ANAGAWA-4-CHOME INAGE-KU, CHIBA, 263, JAPAN SN 0449-3060 J9 J RADIAT RES JI J. Radiat. Res. PD MAR PY 2004 VL 45 IS 1 BP 1 EP 9 PG 9 WC Biology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Radiology, Nuclear Medicine & Medical Imaging GA 825GK UT WOS:000221743900001 PM 15133283 ER PT J AU Dorsey, JT Poteet, CC Wurster, KE Chen, RR AF Dorsey, JT Poteet, CC Wurster, KE Chen, RR TI Metallic thermal protection system requirements, environments, and integrated concepts SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB Achieving the ultimate goal of an economically viable reusable launch vehicle will eventually require developing Federal Aviation Regulation-type performance-based requirements and certification by the Federal Aviation Administration, as is currently done for commercial transports. Because the necessary requirements do not currently exist, there is no verifiable and traceable link between thermal protection system design implementation and resulting performance, safety, and cost. An initial attempt has been made to outline a set of performance-based thermal protection system design requirements. Critical requirements that will have a profound effect on the economic viability of a reusable launch vehicle, such as those for ground hail strike, lightning strike, bird strike, rain/rain erosion, and on-orbit debris/micrometeoroid hypervelocity impact have been proposed. In addition to design requirements, the importance of both compiling a comprehensive loads envelope and deriving time- and location-consistent loads for thermal protection system design and sizing is addressed. Including ascent abort trajectories as limit-load cases and on-orbit debris/micrometeoroid hypervelocity impact as one of the discrete-source-damage cases is imperative because of their significant impact on thermal protection system design and resulting performance, reliability, and operability. General features of a suite of integrated airframe concepts is summarized, and the specific details of a metallic thermal protection system concept having design flexibility that enables weight and operability to be traded and balanced is described. C1 NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Vehicle Anal Branch, Hampton, VA 23681 USA. Lockheed Martin Space Operat, Hampton, VA 23681 USA. RP Dorsey, JT (reprint author), NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. NR 20 TC 16 Z9 17 U1 0 U2 9 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 162 EP 172 DI 10.2514/1.9173 PG 11 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200002 ER PT J AU Poteet, CC Abu-Khajeel, H Hsu, SY AF Poteet, CC Abu-Khajeel, H Hsu, SY TI Preliminary thermal-mechanical sizing of a metallic thermal protection system SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB A process is developed to perform thermal and structural analysis and sizing and to perform sensitivity studies on the latest metallic thermal protection system developed at NASA Langley Research Center. The process defined can be used to determine appropriate materials and approximate thicknesses and is the basis for initial thermal protection system weight estimates. Metallic thermal protection systems are a key technology for reducing the cost of reusable launch vehicles, offering the combination of increased durability and competitive weights when compared to other systems. Accurate sizing of metallic thermal protection systems requires combined thermal and structural analysis. Initial sensitivity studies were conducted using transient one-dimensional finite element thermal analysis to determine the influence of various design and analysis parameters on thermal protection system weight. The thermal analysis model was then used in combination with static deflection and failure mode analysis of the thermal protection system sandwich panel outer surface to obtain minimum weight configurations at three vehicle stations on the windward centerline of a representative reusable launch vehicle. The coupled nature of the analysis requires an iterative analysis process, which is described. Findings from the sensitivity analysis are reported, along with preliminary designs at the three vehicle stations considered. C1 NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. Lockheed Martin Space Operat, Hampton, VA 23681 USA. RP Poteet, CC (reprint author), NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. NR 22 TC 21 Z9 22 U1 0 U2 8 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 173 EP 182 DI 10.2514/1.9174 PG 10 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200003 ER PT J AU Blosser, ML Chen, RR Schmidt, IH Dorsey, JT Poteet, CC Bird, RK Wurster, KE AF Blosser, ML Chen, RR Schmidt, IH Dorsey, JT Poteet, CC Bird, RK Wurster, KE TI Development of advanced metallic thermal-protection-system prototype hardware SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB A new metallic thermal-protection-system concept has been designed, analyzed, and fabricated. A specific location on a single-stage-to-orbit reusable launch vehicle was selected to develop loads and requirements needed to design prototype panels. The design loads include ascent and entry heating rates, pressures, acoustics, and accelerations. Additional design issues were identified and discussed. An iterative sizing procedure was used to size the thermal protection system panels for thermal and structural loads as part of an integrated wall construction that included the thermal protection system and cryogenic tank structure. The panels were sized to maintain acceptable temperatures on the underlying structure and to operate under the design structural loading. Detailed creep. analyses were also performed on critical components of the panels. Four 18-in.-square metallic thermal-protection-system panels were fabricated. A lightweight, thermally compliant support system to connect the thermal protection system to the cryogenic tank structure was designed and fabricated. C1 NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Lockheed Martin Space Operat, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Vehicle Anal Branch, Hampton, VA 23681 USA. RP Blosser, ML (reprint author), NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. NR 23 TC 29 Z9 34 U1 1 U2 23 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 183 EP 194 DI 10.2514/1.9179 PG 12 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200004 ER PT J AU Blosser, ML AF Blosser, ML TI Fundamental modeling and thermal performance issues for metallic thermal protection system concept SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB A study was performed to develop an understanding of the key factors that govern the performance of metallic thermal protection systems for reusable launch vehicles. A current advanced metallic thermal protection system concept was systematically analyzed to discover the most important factors governing its thermal performance. A large number of relevant factors that influence the thermal analysis and thermal performance system were identified and quantified. Detailed finite element models were developed for predicting the thermal performance of design variations of the metallic thermal protection system concept mounted on a simple, unstiffened structure. The computational models were also used, in an automated iterative procedure, for sizing the metallic thermal protection system to maintain the structure below a specified temperature limit. A statistical sensitivity analysis method, based on orthogonal matrix techniques used in robust design, was used to quantify and rank the relative importance of the various modeling and design factors considered in this study. Thermal performance was shown to be sensitive to several analytical assumptions that should be chosen carefully. Of the design factors studied, the heat capacity of the underlying structure was found to have the greatest effect on thermal performance. Therefore the structure and thermal protection system should be designed concurrently. C1 NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. RP Blosser, ML (reprint author), NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. NR 19 TC 8 Z9 9 U1 0 U2 10 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 195 EP 206 DI 10.2514/1.9182 PG 12 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200005 ER PT J AU Chen, RR Blosser, ML AF Chen, RR Blosser, ML TI Metallic thermal-protection-system panel flutter study SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT 40th Aerospace Sciences Meeting and Exhibit CY JAN 14-17, 2002 CL RENO, NV ID COMPOSITE PANELS; FLOW AB Panel flutter of a metallic thermal protection system (TPS) for a reusable launch vehicle is investigated. The study covers both panel flutter analysis tool development as well as an analysis of a specific metallic TPS configuration for the X-33 experimental vehicle. An analytical tool was developed to predict panel flutter at hypersonic How conditions and at arbitrary flow angles to a structural panel, The nonlinear, hypersonic aerodynamic terms were found to have an insignificant effect on the panel flutter predictions for the X-33 TPS. The honeycomb sandwich that comprises most of the outer surface of the X-33 TPS panel was found to have large margins of safety for panel flutter for all flight conditions. However, the outer overlapping, panel-to-panel seals were predicted to be. susceptible to panel flutter when nearly parallel to the flow. C1 NASA, Langley Res Ctr, Lockheed Martin Space Operat, Hampton, VA 23681 USA. RP Chen, RR (reprint author), NASA, Langley Res Ctr, Lockheed Martin Space Operat, Mail Stop 396, Hampton, VA 23681 USA. NR 9 TC 6 Z9 8 U1 1 U2 7 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 207 EP 212 DI 10.2514/1.9190 PG 6 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200006 ER PT J AU Bird, RK Wallace, TA Sankaran, SN AF Bird, RK Wallace, TA Sankaran, SN TI Development of protective coatings for high-temperature metallic materials SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID NI-CR ALLOYS; OXIDATION AB Metallic material systems with potential for high-temperature operations are critical for many land-based and space-based systems. Advanced alloys with improved elevated temperature properties and/or reduced densities offer improved structural efficiency and longer service life compared to more conventional alloys. However, in extreme operating environments, these alloys require coatings for environmental protection and thermal control. We discuss some results from a program to develop ultrathin, lightweight, protective coatings applied via sol-gel techniques for some emerging high-temperature alloys. The coatings were designed to reduce oxidation, increase emittance, and reduce the catalytic efficiency for recombination of dissociated hot-gas species for the candidate materials. The alloys considered in this study include PM1000 (an oxide dispersion strengthened Ni-based alloy), 602CA Ni-based alloy, and a gamma titanium aluminide alloy. Inconel 617, a Ni-based alloy, was included as a reference. Microstructural analysis and oxidation weight gain results indicated that the coatings significantly reduced oxidation damage during extended high-temperature exposures for these alloys. In addition, one coating system was shown to improve the emittance of Inconel 617. A substantial reduction in the recombination of atomic nitrogen and oxygen at the surface of Inconel 617 substrates in a hot flowing airstream was also observed. C1 NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. Lockheed Martin Space Operat, Langley Program Off, Hampton, VA 23681 USA. RP Bird, RK (reprint author), NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. NR 18 TC 15 Z9 21 U1 3 U2 24 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 213 EP 220 DI 10.2514/1.9191 PG 8 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200007 ER PT J AU Poteet, CC Blosser, ML AF Poteet, CC Blosser, ML TI Improving metallic thermal protection system hypervelocity impact resistance through numerical simulations SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB A design of experiments approach has been implemented using computational hypervelocity impact simulations. The purpose of this study is to determine the most effective place to make minor design changes to an existing metallic thermal protection system to improve hypervelocity impact protection provided to underlying components. Simulations are performed using axisymmetric models in a shock-physics hydrodynamics code and compared with existing experimental data. The axisymmetric models are then used in a statistical sensitivity analysis to determine the influence of design parameters on degree of protection. Several damage metrics are identified and evaluated. Damage metrics related to the extent of substructure damage produce misleading results; however, damage metrics related to the degree of dispersion of the hypervelocity projectile produce results that correspond to physical intuition. Based on analysis of variance results, it is concluded that increasing the spacing between the outer surface and the substructure is the most effective way to increase hypervelocity impact resistance. The second most effective design change is to increase the thickness of the outer foil layer. When design considerations are taken into account for the system in this study, it is explained that increasing the thickness of the outer foil layer is the most practical design change. C1 NASA, Langley Res Ctr, Met & Thermal Struct Branch, Hampton, VA 23681 USA. RP Poteet, CC (reprint author), NASA, Langley Res Ctr, Met & Thermal Struct Branch, Mail Stop 396, Hampton, VA 23681 USA. NR 15 TC 6 Z9 6 U1 1 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 221 EP 231 DI 10.2514/1.9193 PG 11 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200008 ER PT J AU Horvath, TJ Berry, SA Merski, NR Fitzgerald, SM AF Horvath, TJ Berry, SA Merski, NR Fitzgerald, SM TI X-38 experimental aerothermodynamics SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID HEAT-TRANSFER; FLIGHT; RATES AB An overview is provided of the hypersonic aerothermodynamic wind-tunnel program conducted at the NASA Langley Research Center in support of the X-38 development. Global and discrete surface heat transfer, force and moment, surface streamline patterns, and shock shapes were measured on scaled models of the proposed X-38 configuration in different test gases at Mach 6, 10, and 20. The test parametrics include angles of attack from 0 to 50 deg; unit Reynolds numbers from 0.3 x 10(6) to 16 X 10(6)/ft: rudder deflections of 0, 2, and 5 deg; and body-flap deflections from 0 to 30 deg in 2.5-deg increments. Results from hypersonic aerodynamic screening studies that were conducted as the configuration evolved to the present shape are presented. Heavy gas simulation tests have indicated that the primary real-gas effects on X-38 aerodynamics at trim conditions are expected to favorably influence flap effectiveness. Comparisons of the experimental heating and force and moment data to prediction and the current aerodynamic data book are highlighted. The effects of discrete roughness elements on boundary-layer transition were investigated at Mach 6, and the development of a transition correlation for the X-38 vehicle is described. Extrapolation of ground-based heating measurements to flight radiation equilibrium wall temperatures at Mach 6 and 10 were made and generally compared to within 50degreesF of flight prediction. C1 NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NASA, Lyndon B Johnson Space Ctr, GN&C Design & Anal Branch, Houston, TX 77058 USA. RP Horvath, TJ (reprint author), NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NR 63 TC 12 Z9 12 U1 1 U2 10 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 272 EP 292 DI 10.2514/1.9198 PG 21 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200013 ER PT J AU Berry, SA Horvath, TJ Weilmuenster, KJ Alter, SJ Merski, NR AF Berry, SA Horvath, TJ Weilmuenster, KJ Alter, SJ Merski, NR TI X-38 experimental aeroheating at Mach 10 SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT AIAA 35th Thermophysics Conference CY JUN 11-14, 2001 CL ANAHEIM, CA SP Amer Inst Aeronaut & Astronaut ID SCHEMES; FLIGHT AB Details are provided of a recent effort at the NASA Langley Research Center to extend the experimental aeroheating database for the X-38 program to higher-Mach-number conditions. Global surface heat-transfer distributions were measured on 0.0177- and 0.0236-scale models of the proposed X-38 Rev 8.3 configuration at Mach 10 in air. The parametrics that were investigated primarily include freestream unit Reynolds numbers of 0.6 to 2.2 x 10(6)/ft and body-flap deflections of 15, 20, and 25 deg for an angle of attack of 40 deg. The model-scale variance was tested to obtain laminar, transitional, and turbulent heating levels on the deflected body flaps. In addition, a limited investigation of forced boundary-layer transition through the use of discrete roughness elements was performed. Comparisons of the present experimental results to computational predictions and previous experimental data were conducted. Laminar, transitional, and turbulent heating levels were observed on the deflected body flap, which compared favorably to the computational results and to the predicted heating based on the flight aerothermodynamic database. C1 NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. RP Berry, SA (reprint author), NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NR 47 TC 3 Z9 3 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 293 EP 301 DI 10.2514/1.9199 PG 9 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200014 ER PT J AU Hwu, SU Loh, YC Kroll, QD Sham, CC AF Hwu, SU Loh, YC Kroll, QD Sham, CC TI International space station Ku-band communications antenna blockage analysis SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article C1 Lockheed Martin Space Operat, Avion Syst Anal Sect, Houston, TX 77258 USA. NASA, Lyndon B Johnson Space Ctr, Syst Anal & Verificat Branch, Houston, TX 77258 USA. RP Hwu, SU (reprint author), Lockheed Martin Space Operat, Avion Syst Anal Sect, 2400 NASA Rd 1, Houston, TX 77258 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2004 VL 41 IS 2 BP 313 EP 315 DI 10.2514/1.1793 PG 3 WC Engineering, Aerospace SC Engineering GA 813PY UT WOS:000220920200017 ER PT J AU Myhre, G Stordal, F Johnsrud, M Ignatov, A Mishchenko, MI Geogdzhayev, IV Tanre, D Deuze, JL Goloub, P Nakajima, T Higurashi, A Torres, O Holben, B AF Myhre, G Stordal, F Johnsrud, M Ignatov, A Mishchenko, MI Geogdzhayev, IV Tanre, D Deuze, JL Goloub, P Nakajima, T Higurashi, A Torres, O Holben, B TI Intercomparison of satellite retrieved aerosol optical depth over the ocean SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID HIGH-RESOLUTION RADIOMETER; INDIVIDUAL AVHRR CHANNELS; TROPOSPHERIC AEROSOLS; SULFATE AEROSOLS; CLOUD DETECTION; AIR-POLLUTION; SAHARAN DUST; VALIDATION; THICKNESS; ALGORITHM AB For an 8-month period aerosol optical depth (AOD) is compared, derived over global oceans with five different retrieval algorithms applied to four satellite instruments flown on board three satellite platforms. The Advanced Very High Resolution Radiometer (AVHRR) was flown on board NOAA-14, the Ocean Color and Temperature Scanner (OCTS) and the Polarization and Directionality of the Earth's Reflectances (POLDER) on board the Advanced Earth Observing Satellite (ADEOS), and the Total Ozone Mapping Spectrometer (TOMS) on board the Earth Probe satellites. The aerosol data are presented on the same format and converted to the same wavelength in the comparison and can therefore be a useful tool in validation of global aerosol models, in particular models that can be driven with meteorological data for the November 1996 to June 1997 period studied here. Large uncertainties in the global mean AOD are found. There is at least a factor of 2 difference between the AOD from the retrievals. The largest uncertainties are found in the Southern Hemisphere, and the smallest differences mostly near the continents in the Northern Hemisphere. The largest relative differences are probably caused by differences in cloud screening. C1 Univ Oslo, Dept Geophys, N-0315 Oslo, Norway. Norwegian Inst Air Res, Kjeller, Norway. NOAA, NESDIS, Off Res & Applicat, Climate Res & Applicat Div, Washington, DC USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. UST Lille, CNRS, Opt Atmospher Lab, Villeneuve Dascq, France. Univ Tokyo, Ctr Climate Syst Res, Tokyo, Japan. Natl Inst Environm Studies, Tsukuba, Ibaraki, Japan. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. RP Univ Oslo, Dept Geophys, POB 1022,Blindern, N-0315 Oslo, Norway. EM gunnar.myhre@geofysikk.uio.no RI Myhre, Gunnar/A-3598-2008; Ignatov, Alexander/F-5594-2010; Nakajima, Teruyuki/H-2370-2013; Torres, Omar/G-4929-2013; Mishchenko, Michael/D-4426-2012; OI Myhre, Gunnar/0000-0002-4309-476X; Ignatov, Alexander/0000-0002-7463-5944; Nakajima, Teruyuki/0000-0002-9042-504X; Stordal, Frode/0000-0002-5190-6473 NR 61 TC 69 Z9 71 U1 2 U2 15 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 EI 1520-0469 J9 J ATMOS SCI JI J. Atmos. Sci. PD MAR PY 2004 VL 61 IS 5 BP 499 EP 513 DI 10.1175/1520-0469(2004)061<0499:IOSRAO>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 780PR UT WOS:000189390900002 ER PT J AU Kim, S Toivola, Y Cook, RF Char, K Chu, SH Lee, JK Yoon, DY Rhee, HW AF Kim, S Toivola, Y Cook, RF Char, K Chu, SH Lee, JK Yoon, DY Rhee, HW TI Organosilicate spin-on glasses - I. Effect of chemical modification on mechanical properties SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID K HYDROGEN SILSESQUIOXANE; NH3 PLASMA TREATMENT; METHYL SILSESQUIOXANE; SENSING INDENTATION; FILMS AB Methylsilsesquioxane (MSSQ) films were chemically modified by (i) the bulk incorporation of a short-chain polymer or (ii) surface treatment by an NH3 plasma, and the effects of these modifications on elastic, plastic, and fracture properties were investigated. In (i), a copolymer of 10 mol % 1,2-bis(trimethoxysilyl) ethane (BTMSE) and methyltrimethoxysilane was synthesized and cured to form an MSSQ: BTMSE copolymer film. In ( ii), an NH3 plasma treatment was applied to cured MSSQ films for 5, 15, 30, or 60 min. Films were characterized using scanning electron microscopy (SEM), IR spectroscopy, and ellipsometry. Depth-sensing indentation was used to determine plane strain modulus, E', and hardness, H. Indentation traces and SEM images of residual indentation damage were used to determine the threshold load for cracking, Pc. The addition of BTMSE to MSSQ doubled E', H, and P-c relative to MSSQ with a slight increase in relative dielectric constant, k, from 2.70 to 2.86. Apparent E' and H at the surface of plasma-treated films increased with plasma treatment time. IR spectroscopy indicated that improved properties resulted in (i) from increased organic and inorganic networking and in (ii) from the formation of a dense, largely inorganic, surface layer. Such chemical modifications may be used to improve the performance of organosilicates as low-k dielectrics in microelectronic interconnection structures. (C) 2004 The Electrochemical Society. C1 Seoul Natl Univ, Sch Chem Engn, Seoul, South Korea. Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. NASA, Langley Res Ctr, NIA, Hampton, VA 23681 USA. Seoul Natl Univ, Sch Chem, Seoul, South Korea. Sogang Univ, Dept Chem Engn, Seoul, South Korea. RP Kim, S (reprint author), Seoul Natl Univ, Sch Chem Engn, Seoul, South Korea. EM rfc@cems.umn.edu NR 23 TC 24 Z9 25 U1 0 U2 2 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAR PY 2004 VL 151 IS 3 BP F37 EP F44 DI 10.1149/1.1643072 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 773VA UT WOS:000188943800051 ER PT J AU Tsai, HF Tsuda, T Hajj, GA Wickert, J Aoyama, Y AF Tsai, HF Tsuda, T Hajj, GA Wickert, J Aoyama, Y TI Equatorial Kelvin waves observed with GPS occultation measurements (CHAMP and SAC-C) SO JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN LA English DT Article; Proceedings Paper CT International Workshop on GPS Meteorology CY JAN 14-17, 2003 CL Tsukuba, JAPAN ID MICROWAVE LIMB SOUNDER; LOWER STRATOSPHERE; ATMOSPHERE; VARIABILITY; TROPOPAUSE; INDONESIA; GPS/MET AB Structure and propagation of equatorial Kelvin waves during May 2001 and December 2002 are observed from the temperature profiles in the upper troposphere and the lower stratosphere using CHAMP and SAC-C GPS radio occultation data. Kelvin waves derived from temperature fluctuations characterize eastward phase propagation in time-longitude section and eastward phase tilts with height in altitude-longitude section between 10 and 30 km. The phase progression spans the range indicating the continuity of Kelvin waves from the upper troposphere to the lower stratosphere. Results show that near the tropopause, Kelvin waves fluctuate temperature by 2 K in general, with wave periods of 12.5-14 days for zonal wave number 1 and 9.3-11.0 days for wave number 2, and vertical wavelengths of 7.6-8.5 km in 2001 and of 4.4-5.8 km in 2002. C1 Kyoto Univ, RASC, Radio Sci Ctr Space & Atmosphere, Uji, Kyoto, Japan. CALTECH, JPL, Pasadena, CA 91125 USA. Geoforschungszentrum Potsdam, Dept Geodesy & Remote Sensing 1, D-14473 Potsdam, Germany. Kyoto Univ, RASC, Uji, Kyoto, Japan. RP Tsai, HF (reprint author), Natl Space Program Off, 8F,9,Jhanye 1st Rd, Hsinchu 30077, Taiwan. EM hftsai@nspo.org.tw RI Wickert, Jens/A-7257-2013; tsuda, toshitaka/A-3035-2015 NR 21 TC 19 Z9 20 U1 0 U2 3 PU METEOROLOGICAL SOC JAPAN PI TOKYO PA C/O JAPAN METEOROLOGICAL AGENCY 1-3-4 OTE-MACHI, CHIYODA-KU, TOKYO, 100-0004, JAPAN SN 0026-1165 EI 2186-9057 J9 J METEOROL SOC JPN JI J. Meteorol. Soc. Jpn. PD MAR PY 2004 VL 82 IS 1B BP 397 EP 406 DI 10.2151/jmsj.2004.397 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 820UE UT WOS:000221414100013 ER PT J AU De la Torre, A Tsuda, T Hajj, GA Wickert, J AF De la Torre, A Tsuda, T Hajj, GA Wickert, J TI A global distribution of the stratospheric gravity wave activity from GPS occultation profiles with SAC-C and CHAMP SO JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN LA English DT Article; Proceedings Paper CT International Workshop on GPS Meteorology CY JAN 14-17, 2003 CL Tsukuba, JAPAN ID RADIO OCCULTATION; MU-RADAR; ATMOSPHERE; VARIABILITY; VARIANCE; TEMPERATURES; FLUCTUATIONS; GPS/MET; ENERGY; ANDES AB We have analysed the gravity wave activity using temperature profiles retrieved from the GPS occultation experiments on board the SAC-C and CHAMP satellites. By dividing the latitude and longitude ranges, here considered in individual cells, the variability of wave energy as a function of altitude observed in both hemispheres during October, November and December 2001 is presented. Some features were repeatedly observed during the three months. Nevertheless, as most available occultations were occurred during November, we begin showing results from this month. Significant differences detected during October are only pointed out at midlatitudes, provided that sufficient number of occultations are available. A significantly larger wave activity at 40-60degreesN with respect to 40-60degreesS is detected during this month. Differences between both the hemispheres are discussed and compared with previous results. Wave activity enhancements at equatorial regions above Brazil, Indonesia and India are found to be correlated with outgoing longwave radiation data. Vertical fluctuations with lengths above and below 3.5 km are considered separately, in order to identify the contribution of Kelvin and Rossby-gravity waves. In both cases, for long and short fluctuations and at the upper troposphere as well as at the lower stratosphere, there is a height interval of several kilometers where a systematic enhanced wave activity is observed. Its average height is progressively decreasing with increasing latitude, same as the height variation in the tropopause location. Longitudinal enhancements are also detected mainly around the equator and at midlatitudes. A clear signature is observed locally in the Southern Hemisphere (SH) at midlatitudes and 70-65degreesW, for vertical wavelengths longer than 3.5 km. It corresponds to mountain waves forced by the Andes Range, observed whenever occultations are available in this cell. C1 Kyoto Univ, Radio Sci Ctr Space & Atmosphere, Kyoto 6110011, Japan. CALTECH, Jet Prop Lab, Pasadena, CA USA. Geoforschungszentrum Potsdam, Sect Geodesy & Remote Sensing, D-14473 Potsdam, Germany. RP De la Torre, A (reprint author), Kyoto Univ, Radio Sci Ctr Space & Atmosphere, Kyoto 6110011, Japan. EM torre@kurasc.kyoto-u.ac.jp RI Wickert, Jens/A-7257-2013; tsuda, toshitaka/A-3035-2015 NR 25 TC 15 Z9 16 U1 0 U2 3 PU METEOROLOGICAL SOC JPN PI TOKYO PA C/O JPN METEOROL AGENCY 1-3-4 OTE-MACHI, CHIYODA-KU, TOKYO, JAPAN SN 0026-1165 J9 J METEOROL SOC JPN JI J. Meteorol. Soc. Jpn. PD MAR PY 2004 VL 82 IS 1B BP 407 EP 417 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 820UE UT WOS:000221414100014 ER PT J AU Zhu, DM Vassen, R Faber, KT AF Zhu, DM Vassen, R Faber, KT TI Untitled SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Editorial Material C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Forschungszentrum Julich, IWV Forschungszentrum, Julich, Germany. Northwestern Univ, Evanston, IL USA. RP Zhu, DM (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RI Faber, Katherine/B-6741-2009 NR 0 TC 7 Z9 7 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD MAR PY 2004 VL 13 IS 1 BP 3 EP 3 DI 10.1361/10599630418257 PG 1 WC Materials Science, Coatings & Films SC Materials Science GA 803IY UT WOS:000220226000001 ER PT J AU Eldridge, JI Bencic, TJ Allison, SW Beshears, DL AF Eldridge, JI Bencic, TJ Allison, SW Beshears, DL TI Depth-penetrating temperature measurements of thermal barrier coatings incorporating thermographic phosphors SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Article DE temperature measurement; thermal barrier coatings; thermographic phosphors ID THERMOMETRY; LIFETIME; Y2O3-EU; ENGINES AB Thermographic phosphors have been previously demonstrated to provide effective non-contact, emissivity-independent surface temperature measurements. Due to the translucent nature of thermal barrier coatings (TBCs), thermographic-phosphor-based temperature measurements can be extended beyond the surface to provide depth-selective temperature measurements by incorporating the thermographic phosphor layer at the depth where the temperature measurement is desired. In this paper, thermographic phosphor (Y2O3:Eu) fluorescence decay time measurements are demonstrated to provide through-the-coating-thickness temperature readings up to 1100 degreesC with the phosphor layer residing beneath a 100-mum-thick TBC (plasma-sprayed 8 wt.% yttria-stabilized zirconia). With an appropriately chosen excitation wavelength and detection configuration, it is shown that sufficient phosphor emission is generated to provide effective temperature measurements, despite the attenuation of both the excitation and emission intensities by the overlying TBC. This depth-penetrating temperature measurement capability should prove particularly useful for TBC diagnostics where a large thermal gradient is typically present across the TBC thickness. The fluorescence decay from the Y2O3:Eu layer exhibited both an initial short-term exponential rise and a longer-term exponential decay. The rise time constant was demonstrated to provide better temperature indication below 500 degreesC while the decay time constant was a better indicator at higher temperatures. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Eldridge, JI (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM Jeffrey.I.Eldridge@nasa.gov OI Allison, Stephen/0000-0002-5887-5403 NR 10 TC 30 Z9 30 U1 2 U2 8 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD MAR PY 2004 VL 13 IS 1 BP 44 EP 50 DI 10.1361/10599630418095 PG 7 WC Materials Science, Coatings & Films SC Materials Science GA 803IY UT WOS:000220226000004 ER PT J AU Smialek, JL AF Smialek, JL TI Improved oxidation life of segmented plasma sprayed 8YSZ thermal barrier coatings SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Article DE low sulfur superalloys; no bond coat; oxidation; segmented thermal barrier coating ID SCALE ADHESION; ALUMINA; SPALLATION; FILMS AB Unconventional plasma sprayed thermal barrier coating (TBC) systems were produced and evaluated by interrupted or cyclic furnace oxidation life testing. First, approximately 250 mum thick 8YSZ coatings were directly sprayed onto grit blasted surfaces of PWA 1484, without a bond coat, to take advantage of the excellent oxidation resistance of this superalloy. For nominal sulfur (S) contents of 1 ppmw, total coating separation took place at relatively short times (200 h at 1100 degreesC). Reductions in the S content, by melt desulfurization commercially (0.3 ppmw) or by hydrogen (H(2)) annealing in the laboratory (0.01 ppmw), improved scale adhesion and extended life appreciably, by factors of 5-10. However, edge-initiated failure persisted, producing massive delamination as one sheet of coating. Secondly, surfaces of melt desulfurized PWA 1484 were machined with a grid of grooves or ribs (similar to250 mum wide and high), resulting in a segmented TBC surface macrostructure, for the purpose of subverting this failure mechanism. In this case, failure occurred only as independent, single-segment events. For grooved samples, 1100 degreesC segment life was extended to similar to1000 h for 5 mm wide segments, with no failure observed out to 2000 h for segments less than or equal to2.5 mm wide. Ribbed samples were even more durable, and segments less than or equal to6 mm remained intact for 2000 h. Larger segments failed by buckling at times inversely related to the segment width and decreased by oxidation effects at higher temperatures. This critical buckling size was consistent with that predicted for elastic buckling of a TBC plate subject to thermal expansion mismatch stresses. Thus, low S substrates demonstrate appreciable coating lives without a bond coat, while rib segmenting extends life considerably. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Smialek, JL (reprint author), NASA, Glenn Res Ctr, 21000 Brookpk Rd,MS 106, Cleveland, OH 44135 USA. EM Smialek@grc.nasa.gov NR 24 TC 8 Z9 8 U1 0 U2 3 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD MAR PY 2004 VL 13 IS 1 BP 66 EP 75 DI 10.1361/10599630418167 PG 10 WC Materials Science, Coatings & Films SC Materials Science GA 803IY UT WOS:000220226000007 ER PT J AU Zhu, DM Nesbitt, JA Barrett, CA McCue, TR Miller, RA AF Zhu, DM Nesbitt, JA Barrett, CA McCue, TR Miller, RA TI Furnace cyclic oxidation behavior of multicomponent low conductivity thermal barrier coatings SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Article DE grain growth; oxide defect cluster; phase transformation and toughening; thermal barrier coatings; thermal conductivity; thermal cyclic life ID ZIRCONIA-YTTRIA; SYSTEM AB Ceramic thermal barrier coatings (TBCs) will play an increasingly important role in advanced gas turbine engines due to their ability to further increase engine operating temperatures and reduce cooling, thus helping achieve future engine low emission, high efficiency, and improved reliability goals. Advanced multicomponent zirconia (ZrO2)-based TBCs are being developed using an oxide defect clustering design approach to achieve the required coating low thermal conductivity and high-temperature stability. Although the new composition coatings were not yet optimized for cyclic durability, an initial durability screening of the candidate coating materials was conducted using conventional furnace cyclic oxidation tests. In this paper, furnace cyclic oxidation behavior of plasma-sprayed ZrO2-based defect cluster TBCs was investigated at 1163 degreesC using 45 min hot-time cycles. The ceramic coating failure mechanisms were studied using scanning electron microscopy (SEM) combined with x-ray diffraction (XRD) phase analysis after the furnace tests. The coating cyclic lifetime is also discussed in relation to coating processing, phase structures, dopant concentration, and other thermo-physical properties. C1 NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. RP Zhu, DM (reprint author), NASA, John H Glenn Res Ctr, 21000 Brookpk Rd, Cleveland, OH 44135 USA. EM Dongming.Zhu@grc.nasa.gov NR 25 TC 25 Z9 26 U1 0 U2 9 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD MAR PY 2004 VL 13 IS 1 BP 84 EP 92 DI 10.1361/1059963018185 PG 9 WC Materials Science, Coatings & Films SC Materials Science GA 803IY UT WOS:000220226000009 ER PT J AU Motayed, A Jah, M Sharma, A Anderson, WT Litton, CW Mohammad, SN AF Motayed, A Jah, M Sharma, A Anderson, WT Litton, CW Mohammad, SN TI Two-step surface treatment technique: Realization of nonalloyed low-resistance Ti/Al/Ti/Au ohmic contact to n-GaN SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID P-TYPE GAN; RESISTIVITY; TEMPERATURE; SEMICONDUCTORS; NITRIDE AB A novel two-step surface treatment method has been developed to realize low resistance nonalloyed ohmic contact to n-type GaN doped with Si to 6 x 10(17) cm(-3). The removal of native oxide (oxides and hydroxides) formed on GaN surface is crucial for successful creation of nonalloyed low resistance ohmic contact. In the case of GaN, plasma etching of the material surface prior to metal deposition holds promise for developing such nonalloyed ohmic contacts. In this article, the effects of the postetch chemical treatment of the n-type GaN surface on the Ti based nonalloyed contact performance have been investigated. Contacts on samples without reactive ion etching (RIE) showed Schottky behavior. However, contacts on samples with 15 s of RIE using Cl-2 showed ohmic behavior. The contact resistivity of this contact reached to rho(s) = 1.2 x 10(-3) Omega cm(2). Treating the RIE etched sample in boiling aqua regia for 5 min yielded a contact resistivity on the order of 3.6 x 10(-4) Omega cm(2) . Dramatic improvement in current-voltage characteristics was observed after boiling RIE etched samples in KOH for 5 min. It yielded contact resistivity oil the order of rho(s)similar to7 x 10(-5) Omega cm(2). which is comparable to the contact resistivity of alloyed contacts. It was demonstrated, for the first time, that chemical treatment of postetched GaN surfaces employing KOH is very promising, for new generation of nonalloyed ohmic contacts. This study suggested that the reduction of contact resistivity results from the effective removal of surface oxides and hydroxides, which act as an impeding barrier for electron transport. (C) 2004 American Vacuum Society. C1 Howard Univ, Dept Elect Engn, Washington, DC 20059 USA. NASA, Goddard Space Flight Ctr, Component Technol Branch, Greenbelt, MD 20771 USA. USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. USAF, Res Lab, Elect Res Directorate, Wright Patterson AFB, OH 45433 USA. RP Mohammad, SN (reprint author), Howard Univ, Dept Elect Engn, 2300 6th St NW, Washington, DC 20059 USA. EM snmohammad2002@yahoo.com NR 23 TC 12 Z9 14 U1 0 U2 8 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAR-APR PY 2004 VL 22 IS 2 BP 663 EP 667 DI 10.1116/1.1667506 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 816ED UT WOS:000221092300037 ER PT J AU Vinogradov, S Vinogradova, N Kamenkovich, V Nechaev, D AF Vinogradov, S Vinogradova, N Kamenkovich, V Nechaev, D TI Temperature and salinity variability in the Mississippi bight SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article AB Conductivity temperature depth (CTD) profile data from five surveys performed by the R/V Pelican in the Mississippi Bight in February, May, November 1999; and January-February and August-September 2000 have been analysed. The data were collected within the framework of the Northern Gulf of Mexico Littoral Initiative (NGLI). The analysis of the T-S diagrams demonstrated substantial seasonal changes. Some estimates of the spatial variability at different scales were suggested. The analysis of the T-S data obtained at time-series stations revealed some interesting effects such as along-shelf intrusion of deep water into the coastal system and fine vertical T-S structures in shallow passes between the barrier islands. C1 Univ So Mississippi, Stennis Space Ctr, Dept Marine Sci, Hattiesburg, MS 39406 USA. RP Vinogradov, S (reprint author), Univ So Mississippi, Stennis Space Ctr, Dept Marine Sci, Hattiesburg, MS 39406 USA. NR 7 TC 4 Z9 4 U1 1 U2 3 PU MARINE TECHNOLOGY SOC INC PI COLUMBIA PA 5565 STERRETT PLACE, STE 108, COLUMBIA, MD 21044 USA SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD SPR PY 2004 VL 38 IS 1 BP 52 EP 60 PG 9 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 827MT UT WOS:000221904700008 ER PT J AU Schlegel, TT Kulecz, WB DePalma, JL Feiveson, AH Wilson, JS Rahman, MA Bungo, MW AF Schlegel, TT Kulecz, WB DePalma, JL Feiveson, AH Wilson, JS Rahman, MA Bungo, MW TI Real-time 12-lead high-frequency QRS electrocardiography for enhanced detection of myocardial ischemia and coronary artery disease SO MAYO CLINIC PROCEEDINGS LA English DT Review ID SIGNAL-AVERAGED ECG; CONVENTIONAL ELECTROCARDIOGRAM; SPECTRAL-ANALYSIS; HEALTHY-SUBJECTS; POTENTIALS; COMPONENTS; LEADS; DOGS; INFARCTION; STANDARD AB Several studies have shown that diminution of the high-frequency (HF; 150-250 Hz) components present within the central portion of the QRS complex of an electrocardiogram (ECG) is a more sensitive indicator for the presence of myocardial ischemia than are changes in the ST segments of the conventional low-frequency ECG. However, until now, no device has been capable of displaying, in real time on a beat-to-beat basis, changes, in these HF QRS ECG components in a continuously monitored patient. Although several software programs have been designed to acquire the HF components over the entire QRS interval, such programs have involved laborious off-line calculations and postprocessing, limiting their clinical utility. We describe a personal computer-based ECG software program developed recently at the National Aeronautics and Space Administration (NASA) that acquires; analyzes, and displays HF QRS components in, each of the 12 conventional ECG leads in real time. The system also updates these signals and their related derived parameters in real time on a beat-to-beat basis for any chosen monitoring period and simultaneously displays the diagnostic information from the conventional (low-frequency) 12-lead ECG. The real-time NASA HF QRS ECG software is being evaluated currently in multiple clinical settings in North America. We describe its potential usefulness in the diagnosis of myocardial ischemia and coronary artery disease. C1 NASA, Lyndon B Johnson Space Ctr, Neuroauton Lab, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Wyle Labs, Houston, TX 77058 USA. Colorado State Univ, Dept Engn, Pueblo, CO USA. Baylor Univ, Dept Engn, Waco, TX 76798 USA. Univ Texas, Med Branch, Div Cardiol, Galveston, TX 77550 USA. Univ Texas, Houston Med Sch, Houston, TX USA. RP Schlegel, TT (reprint author), NASA, Lyndon B Johnson Space Ctr, Neuroauton Lab, Mail Code SK3, Houston, TX 77058 USA. EM todd.t.schlegel@nasa.gov NR 36 TC 40 Z9 45 U1 1 U2 6 PU MAYO CLINIC PROCEEDINGS PI ROCHESTER PA 660 SIEBENS BLDG MAYO CLINIC, ROCHESTER, MN 55905 USA SN 0025-6196 J9 MAYO CLIN PROC JI Mayo Clin. Proc. PD MAR PY 2004 VL 79 IS 3 BP 339 EP 350 PG 12 WC Medicine, General & Internal SC General & Internal Medicine GA 778MC UT WOS:000189244500009 PM 15008608 ER PT J AU Kojima, J Nguyen, QV AF Kojima, J Nguyen, QV TI Measurement and simulation of spontaneous Raman scattering in high-pressure fuel-rich H-2-air flames SO MEASUREMENT SCIENCE AND TECHNOLOGY LA English DT Article DE laser Raman scattering; rotational temperature; high-pressure flame; Raman spectroscopy; molecular spectra modelling; combustion diagnostics ID HYDROGEN CARS THERMOMETRY; RAYLEIGH-LIF MEASUREMENTS; NARROW-BAND; TEMPERATURE-MEASUREMENTS; TURBULENT COMBUSTION; NONPREMIXED FLAMES; EXCIMER-LASER; DIAGNOSTICS; H-2; FRACTION AB Rotational and vibrational spontaneous Raman scattering (SRS) spectra of H-2, N-2 and H2O have been measured in H-2-air flames at pressures up to 30.4 bar as a first step towards establishing a comprehensive Raman spectral database for temperatures and species in high-pressure combustion. We have obtained an initial set of measurements that indicate the spectra are of sufficient quality in terms of spectral resolution, wavelength coverage and signal-to-noise ratio for use in the development of transferable standards for the cross-talk calibration matrix. The fully resolved Stokes and anti-Stokes shifted spectra were collected in the visible wavelength range (400-700 nm) using pulse-stretched 532 nm excitation and a spectrograph fitted with a non-intensified CCD detector and a high-speed shutter. Temperatures were determined via the intensity distribution of rotational H-2 lines at stoichiometric and fuel-rich conditions. A discussion of the temperature measurement accuracy in terms of the number of laser shots, including a single-shot measurement, is presented. Theoretical Raman spectra of hydrogen were calculated using a semi-classical anharmonic-oscillator model with recent pressure broadening data and were compared with experimental data. The data and simulation showed good agreement at different equivalence ratios and pressures and indicate that high-J rotational lines of H-2 may interfere with the N-2 vibrational Q-branch lines, which could lead to errors in N-2-Raman thermometry based on the line-fitting method. In addition, the relative intensities of the O- and S-branches to the Q-branch were determined theoretically and the result indicates that further studies of spectral interferences including contributions from O- and S-branches should be pursued. Finally, from a comparison of N2 Q-branch spectra in lean H-2-air flames at nearly atmospheric (1.2 bar) and high pressure (30.4 bar), we found no significant line-narrowing or -broadening effects at a spectral resolution of 0.04 nm. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM Jun.Kojima@grc.nasa.gov; Quang-Viet.Nguyen@nasa.gov NR 42 TC 19 Z9 20 U1 2 U2 16 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-0233 EI 1361-6501 J9 MEAS SCI TECHNOL JI Meas. Sci. Technol. PD MAR PY 2004 VL 15 IS 3 BP 565 EP 580 AR PII S0957-0233(04)70029-6 DI 10.1088/0957-0233/15/3/009 PG 16 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 804BR UT WOS:000220274700010 ER PT J AU Binzel, RP Perozzi, E Rivkin, AS Rossi, A Harris, AW Bus, SJ Valsecchi, GB Slivan, SM AF Binzel, RP Perozzi, E Rivkin, AS Rossi, A Harris, AW Bus, SJ Valsecchi, GB Slivan, SM TI Dynamical and compositional assessment of near-Earth object mission targets SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID ASTEROID SPECTROSCOPIC SURVEY; MAIN-BELT; PHASE-II; METEORITES; TELESCOPE; TAXONOMY; SPECTRA; IRON; IRTF AB Using an H-plot analysis, we identify 234 currently known near-Earth objects that are accessible for rendezvous with a "best case" delta-V of less than 7 km/s. We provide a preliminary compositional interpretation and assessment of these potential targets by summarizing the taxonomic properties for 44 objects. Results for one-half (22) of this sample are based on new spectroscopic measurements presented here. Our approach provides an easy-to-update method for giving guidelines to both observers and mission analysts for focusing on objects for which actual mission opportunities are most likely to be found. Observing prospects are presented for categorizing the taxonomic properties of the most accessible targets that are not yet measured. C1 MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. Telespazio SpA, Rome, Italy. CNR, ISTI, I-56124 Pisa, Italy. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Inst Astron, Hilo, HI 96720 USA. CNR, Ist Astrofis Spaziale & Fis Cosm, Rome, Italy. RP Binzel, RP (reprint author), MIT, Dept Earth Atmospher & Planetary Sci, 77 Massachusetts Ave, Cambridge, MA 02139 USA. EM rpb@mit.edu RI Rivkin, Andrew/B-7744-2016; Rossi, Alessandro/D-4408-2016; OI Rivkin, Andrew/0000-0002-9939-9976; Rossi, Alessandro/0000-0001-9311-2869; Valsecchi, Giovanni/0000-0002-2915-1465 NR 46 TC 40 Z9 42 U1 0 U2 5 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD MAR PY 2004 VL 39 IS 3 BP 351 EP 366 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 812HM UT WOS:000220830600001 ER PT J AU Ostro, SJ Benner, LAM Nolan, MC Magri, C Giorgini, JD Scheeres, DJ Broschart, SB Kaasalainen, M Vokrouhlicky, D Chesley, SR Margot, JL Jurgens, RF Rose, R Yeomans, DK Suzuki, S De Jong, EM AF Ostro, SJ Benner, LAM Nolan, MC Magri, C Giorgini, JD Scheeres, DJ Broschart, SB Kaasalainen, M Vokrouhlicky, D Chesley, SR Margot, JL Jurgens, RF Rose, R Yeomans, DK Suzuki, S De Jong, EM TI Radar observations of asteroid 25143 Itokawa (1998 SF36) SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID C MISSION TARGET; CCD PHOTOMETRY; 433 EROS; EVOLUTION; GOLEVKA; MODEL; SHAPE AB We observed 25143 Itokawa, the target of Japan's Hayabusa (MUSES-C) sample-return mission, during its 2001 close approach at Arecibo on twelve dates during March 18-April 9 and at Goldstone on nine dates during March 20-April 2. We obtained delay-Doppler images with range resolutions of 100 ns (15 m) at Arecibo and 125 ns (19 m) at Goldstone. Itokawa's average circular polarization ratio at 13 cm, 0.26 +/- 0.04, is comparable to that of Eros, so its cm-to-m surface roughness probably is comparable to that on Eros. Itokawa's radar reflectivity and polarization properties indicate a near-surface bulk density within 20% of 2.5 g cm(-3). We present a preliminary estimate of Itokawa's shape, reconstructed from images with rather limited rotation-phase coverage, using the method of Hudson (1993) and assuming the lightcurve-derived spin period (12.132 hr) and pole direction (ecliptic long., lat. = 355degrees, -84degrees) of Kaasalainen et al. (2003). The model can be described as a slightly asymmetrical, slightly flattened ellipsoid with extents along its principal axes of 548 x 312 x 276 m +/- 10%. Itokawa's topography is very subdued compared to that of other asteroids for which spacecraft images or radar reconstructions are available. Similarly, gravitational slopes on our Itokawa model average only 9degrees and everywhere are less than 27degrees. The radar-refined orbit allows accurate identification of Itokawa's close planetary approaches through 2170. If radar ranging planned for Itokawa's 2004 apparition succeeds, then tracking of Hayabusa during its 2005 rendezvous should reveal Yarkovsky perturbation of the asteroid's orbit. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Arecibo Observ, Arecibo, PR 00612 USA. Univ Maine Farmington, Farmington, ME 04938 USA. Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA. Univ Helsinki, Rolf Nevanlinna Inst, FIN-00014 Helsinki, Finland. Univ Oulu, FIN-99600 Sodankyla, Finland. Charles Univ, Inst Astron, CZ-18000 Prague 8, Czech Republic. Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. RP Ostro, SJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM ostro@reason.jpl.nasa.gov RI Margot, Jean-Luc/A-6154-2012; Nolan, Michael/H-4980-2012; Kaasalainen, Mikko/G-4236-2014 OI Margot, Jean-Luc/0000-0001-9798-1797; Nolan, Michael/0000-0001-8316-0680; NR 25 TC 36 Z9 37 U1 0 U2 3 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD MAR PY 2004 VL 39 IS 3 BP 407 EP 424 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 812HM UT WOS:000220830600005 ER PT J AU Pratt, GW Mukai, K Hassall, BJM Naylor, T Wood, JH AF Pratt, GW Mukai, K Hassall, BJM Naylor, T Wood, JH TI An XMM-Newton observation of the nova-like variable UX UMa: spatially and spectrally resolved two-component X-ray emission SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE binaries : eclipsing; stars : individual : UX UMa; novae, cataclysmic variables; X-rays : stars ID OY CARINAE; URSAE-MAJORIS; CATACLYSMIC VARIABLES; ACCRETION DISKS; HT CASSIOPEIAE; WHITE-DWARF; ECLIPSE; QUIESCENCE; SUPEROUTBURST; TEMPERATURE AB In the optical and ultraviolet regions of the electromagnetic spectrum, UX Ursae Majoris is a deeply eclipsing cataclysmic variable. However, no soft X-ray eclipse was detected in ROSAT observations. We have obtained a 38 ksec XMM-Newton observation to constrain further the origin of the X-rays. The combination of spectral and timing information allows us to identify two components in the X-ray emission of the system. The soft component, dominant below photon energies of 2 keV, can be fitted with a multitemperature plasma model and is uneclipsed. The hard component, dominant above 3 keV, can be fitted with a kT similar to 5 keV plasma model and appears to be deeply eclipsed. We suggest that the most likely source of the hard X-ray emission in UX UMa, and other systems in high mass transfer states, is the boundary layer. C1 CEA Saclay, Serv Astrophys, Orme Merisiers, F-91191 Gif Sur Yvette, France. MPE Garching, D-85478 Garching, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Cent Lancashire, Ctr Astrophys, Preston PR1 2HE, Lancs, England. Univ Exeter, Sch Phys, Exeter EX4 4QL, Devon, England. Univ Keele, Sch Chem & Phys, Keele ST5 5BG, Staffs, England. Univ Space Res Assoc, Columbia, MD USA. RP Pratt, GW (reprint author), CEA Saclay, Serv Astrophys, Orme Merisiers, Bat 709, F-91191 Gif Sur Yvette, France. EM gwp@mpe.mpg.de; mukai@milkyway.gsfc.nasa.gov; bjmhassall@uclan.ac.uk; T.Naylor@exeter.ac.uk; jhw@astro.keele.ac.uk RI Naylor, Tim /A-9465-2015 NR 26 TC 13 Z9 13 U1 0 U2 1 PU BLACKWELL PUBLISHING LTD PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAR 1 PY 2004 VL 348 IS 3 BP L49 EP L53 DI 10.1111/j.1365-2966.2004.07574.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 802JV UT WOS:000220160700004 ER PT J AU Cardinali, C Rukhovets, L Tenenbaum, J AF Cardinali, C Rukhovets, L Tenenbaum, J TI Jet stream analysis and forecast errors using GADS aircraft observations in the DAO, ECMWF, and NCEP models SO MONTHLY WEATHER REVIEW LA English DT Article ID DATA ASSIMILATION SYSTEM; MULTISCALE GEM MODEL; METEOROLOGICAL-CENTER; PART II; WINDS; IMPACT AB Peak analyzed jet stream wind speeds are compared with independent aircraft observations over Canada and the continental United States. The results permit a study of the accuracy of analyzed jet streak strength for the data-sparse 85% of the earth's surface versus the data-dense 15%. The observations come from the Global Aircraft Data Set ( GADS) experiment, which since 1996 has collected flight data recorder information from every flight of 56 British Airways 747-400 aircraft. The study is timely because automated aircraft observations are reaching their near-asymptotic limits (there are not many uncovered commercial aircraft routes left), and we are about to enter a new, third-generation, satellite-sounding-instrument era. Future reanalyses will mix time periods from both eras. This study gives an estimate of the analysis accuracy of data assimilation using second-generation satellite systems. The results show that major current generation assimilation models have peak wind speed errors of 25% to 29% over data-sparse Canada compared with 22% to 25% over the data-dense continental United States. When these additional aircraft observations are assimilated as a part of the normal observational input data stream, a small but statistically significant improvement is shown for 1-month forecast experiments over two consecutive winters. C1 SUNY Coll Purchase, Div Nat Sci, Purchase, NY 10577 USA. European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England. NASA, Goddard Space Flight Ctr, Global Modeling & Data Assimilat Off, Greenbelt, MD 20771 USA. RP Tenenbaum, J (reprint author), SUNY Coll Purchase, Div Nat Sci, Purchase, NY 10577 USA. EM joel@zephyr.ns.purchase.edu NR 30 TC 9 Z9 9 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD MAR PY 2004 VL 132 IS 3 BP 764 EP 779 DI 10.1175/1520-0493(2004)132<0764:JSAAFE>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 801RV UT WOS:000220113900007 ER PT J AU Yun, MH Myung, NV Vasquez, RP Lee, CS Menke, E Penner, RM AF Yun, MH Myung, NV Vasquez, RP Lee, CS Menke, E Penner, RM TI Electrochemically grown wires for individually addressable sensor arrays SO NANO LETTERS LA English DT Article ID CARBON NANOTUBE; BUILDING-BLOCKS; NANOWIRES; DEVICES; INTEGRATION; TRANSISTOR; CIRCUITS AB We report on the electrochemical growth of micro/nanowire devices using e-beam-patterned electrolyte channels, potentially enabling the controlled fabrication of individually addressable arrays. The concept of growing single wires and small arrays using this technique is demonstrated by single and double wires of Pd and polypyrrole with 500-nm and 1-mum widths up to 7-mum lengths and 200-nm thicknesses. The use of Pd wires as hydrogen sensors and polypyrrole wires as pH sensors is demonstrated. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. Univ Calif Riverside, Dept Environm Chem & Engn, Riverside, CA 92551 USA. RP Yun, MH (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Minhee.Yun@jpl.nasa.gov RI Penner, Reginald/D-1521-2009; Menke, Erik/D-4305-2009 OI Penner, Reginald/0000-0003-2831-3028; NR 22 TC 201 Z9 203 U1 2 U2 49 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD MAR PY 2004 VL 4 IS 3 BP 419 EP 422 DI 10.1021/nl035069u PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 802NQ UT WOS:000220170600007 ER EF