FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Foltz, JV Blackmon, CM AF Foltz, JV Blackmon, CM TI Matrix composites SO ADVANCED MATERIALS & PROCESSES LA English DT Article AB Metals that are reinforced with particles or filaments of other metals or nonmetallics provide properties that are not possible with the monolithic material. C1 USN, Ctr Surface Warfare, Met Mat Branch, White Oak Lab, Silver Spring, MD 20910 USA. USN, Ctr Surface Warfare, Appl Mat Technol Branch, Dahlgren Lab, Silver Spring, MD USA. RP Foltz, JV (reprint author), USN, Ctr Surface Warfare, Met Mat Branch, White Oak Lab, Silver Spring, MD 20910 USA. NR 0 TC 6 Z9 6 U1 0 U2 1 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 0026-0665 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD DEC PY 1998 VL 154 IS 6 BP 19 EP 23 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 145CX UT WOS:000077354400002 ER PT J AU Cipolla, KM Rockwell, D AF Cipolla, KM Rockwell, D TI Small-scale vortical structures in crossflow plane of a rolling delta wing SO AIAA JOURNAL LA English DT Article C1 Lehigh Univ, Dept Mech Engn, Bethlehem, PA 18015 USA. RP Cipolla, KM (reprint author), USN, Submarine Sonar Dept, Towed & Deployed Sensors Div, Undersea Warfare Ctr, Code 2141,1176 Howell St, Newport, RI 02841 USA. NR 17 TC 7 Z9 7 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1998 VL 36 IS 12 BP 2276 EP 2278 PG 3 WC Engineering, Aerospace SC Engineering GA 148KK UT WOS:000077503900018 ER PT J AU Abels, R AF Abels, R TI Monastic revival and regional identity in early Normandy SO ALBION LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Abels, R (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU APPALACHIAN STATE UNIV PI BOONE PA ALBION/HISTORY DEPT 210 WHITENER HALL, BOONE, NC 28608 USA SN 0095-1390 J9 ALBION JI Albion PD WIN PY 1998 VL 30 IS 4 BP 660 EP 662 DI 10.2307/4053856 PG 3 WC History SC History GA 192CM UT WOS:000080060700007 ER PT J AU Quarles, CS Brodie, JH AF Quarles, CS Brodie, JH TI Primary care of international adoptees SO AMERICAN FAMILY PHYSICIAN LA English DT Article ID CHILDREN; ADOPTION; HEALTH AB International adoptees are presenting to family physicians with increasing frequency U.S. citizens have adopted over 100,000 international children since 1979. Prospective parents may seek advice from their physician during the adoptive process. If available at all, medical information on the child is often scanty. History and physical examination alone are often insufficient for diagnosis of common problems in this population. Adoptive parents may have concerns about growth and development, and appropriate immunizations. In addition, bacterial, viral and parasitic infections endemic in countries of origin create unusual challenges for the U.S. primary care physician. A basic understanding of the process of international adoption, a skillful evaluation of the child and selected laboratory studies enable the family physician to support the prospective parents and assist in a smooth transition of the child into a new family. C1 USN, Dept Family Practice, Bremerton, WA 98312 USA. RP Brodie, JH (reprint author), USN, Dept Family Practice, Bremerton, WA 98312 USA. NR 15 TC 8 Z9 9 U1 0 U2 0 PU AMER ACAD FAMILY PHYSICIANS PI KANSAS CITY PA 8880 WARD PARKWAY, KANSAS CITY, MO 64114-2797 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD DEC PY 1998 VL 58 IS 9 BP 2025 EP 2032 PG 8 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 146PF UT WOS:000077439000010 PM 9861877 ER PT J AU Clenney, TL Franklin-Bond, T AF Clenney, TL Franklin-Bond, T TI Chronic cough SO AMERICAN FAMILY PHYSICIAN LA English DT Article ID LIPOID PNEUMONIA C1 USN Hosp, Jacksonville, FL 32214 USA. RP Clenney, TL (reprint author), USN Hosp, Family Practice Residency,2080 Child St, Jacksonville, FL 32214 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER ACAD FAMILY PHYSICIANS PI KANSAS CITY PA 8880 WARD PARKWAY, KANSAS CITY, MO 64114-2797 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD DEC PY 1998 VL 58 IS 9 BP 2093 EP 2094 PG 2 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 146PF UT WOS:000077439000017 PM 9861882 ER PT J AU Smith, PA Gardner, DR Drown, DB Jederberg, WW Still, K AF Smith, PA Gardner, DR Drown, DB Jederberg, WW Still, K TI Oxidized resin acids in aerosol derived from rosin core solder SO AMERICAN INDUSTRIAL HYGIENE ASSOCIATION JOURNAL LA English DT Article DE aerosol; colophony; dehydroabietic acid; oxidation; resin; soldering ID CONTACT ALLERGY; OCCUPATIONAL ASTHMA; COLOPHONY ROSIN; PRODUCTS; FLUX AB Exposure to rosin during a variety of uses has been associated with dermal and pulmonary sensitization. Oxidized resin acids are present in many rosin products, and have been regarded as the main sensitizing rosin compounds in cases of dermal sensitization. This research describes oxidized resin acids identified in aerosol produced during soldering with rosin Gore solder. Oxidized resin acids found were 7-oxodehydroabietic acid, 15-hydroxydehydroabietic acid, and 7-hydroxydehydroabietic acid. The presence of oxidized compounds known to be dermal sensitizers in aerosol from rosin flux soldering supports the hypothesis that resin acid compounds are pulmonary sensitizers as previously proposed. changes in the composition of resin acid aerosol derived from heated rosin core solder (compared with the parent material) are described. C1 Uniformed Serv Univ Hlth Sci, Dept Prevent Med & Biometr, Bethesda, MD 20814 USA. ARS, USDA, Poisonous Plant Res Lab, Logan, UT USA. Utah State Univ, Ctr Environm Toxicol, Logan, UT 84322 USA. Utah State Univ, Dept Biol, Logan, UT 84322 USA. USN, Med Res Inst, Detachment Toxicol, Wright Patterson AFB, OH USA. RP Smith, PA (reprint author), Uniformed Serv Univ Hlth Sci, Dept Prevent Med & Biometr, Bethesda, MD 20814 USA. RI Smith, Philip/A-6835-2009 OI Smith, Philip/0000-0003-3787-9111 NR 23 TC 5 Z9 5 U1 1 U2 3 PU AMER INDUSTRIAL HYGIENE ASSOC PI FAIRFAX PA 2700 PROSPERITY AVE #250, FAIRFAX, VA 22031-4307 USA SN 0002-8894 J9 AM IND HYG ASSOC J JI Am. Ind. Hyg. Assoc. J. PD DEC PY 1998 VL 59 IS 12 BP 889 EP 894 DI 10.1202/0002-8894(1998)059<0889:ORAIAD>2.0.CO;2 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA 148KL UT WOS:000077504100008 PM 9866169 ER PT J AU Eckman, JE Okamura, B AF Eckman, JE Okamura, B TI A model of particle capture by bryozoans in turbulent flow: Significance of colony form SO AMERICAN NATURALIST LA English DT Article DE bryozoan; suspension feeding; colony; particle capture; turbulence ID ROCKY INTERTIDAL COMMUNITY; MEMBRANIPORA-MEMBRANACEA L; FEEDING CURRENT VELOCITY; BOUNDARY-LAYER; MARINE BRYOZOAN; AMBIENT FLOW; SUSPENSION-FEEDERS; LARVAL SETTLEMENT; UPSTREAM COLONIES; SIZE AB A hydrodynamic model was devdoped to examine particle capture by lophophores of encrusting bryozoans. Particle capture rate is predicted to increase with increasing speed of the feeding current. There should be a large feeding advantage when lophophores are tightly packed and excurrents are vented through chimneys. This prediction contradicts conclusions of an earlier model study and suggests that selection for colony integration has a basis in the acquisition of food. If lophophores are not tightly packed, particle-capture patterns depend on two key ratios: the advection ratio (feeding current velocity to shear velocity) and the separation ratio (lophophore spacing to lophophore diameter). At high separation ratios, particle capture rates should be fairly uniform among zooids. At high advection ratios, lophophores located near the upstream colony edge should experience higher rates of particle capture. Rates of particle capture in turbulent flows should greatly exceed those in laminar flows (of identical speed) when ex current waters are locally remixed into the flow above lophophores. However, when lophophores are tightly packed and excurrents are Vented through chimneys, feeding rates should be identical in turbulent and laminar flows. Thus, colonies that vent excurrents through chimneys may be uniquely able to exploit weak laminar flows. C1 Skidaway Inst Oceanog, Savannah, GA 31411 USA. Univ Reading, Sch Anim & Microbial Sci, Reading RG6 6AJ, Berks, England. RP Eckman, JE (reprint author), Off Naval Res, Code 322BC,800 N Quincy St, Arlington, VA 22217 USA. NR 82 TC 19 Z9 19 U1 1 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0003-0147 J9 AM NAT JI Am. Nat. PD DEC PY 1998 VL 152 IS 6 BP 861 EP 880 DI 10.1086/286214 PG 20 WC Ecology; Evolutionary Biology SC Environmental Sciences & Ecology; Evolutionary Biology GA 141XF UT WOS:000077169000008 PM 18811433 ER PT J AU Bashkansky, M Duncan, MD Reintjes, J AF Bashkansky, M Duncan, MD Reintjes, J TI Signal processing for improving field cross-correlation function in optical coherence tomography SO APPLIED OPTICS LA English DT Article AB Signal processing is used to enhance the field cross-correlation function in optical coherence tomography (OCT). This paper shows how the spurious signal resulting from an imperfect spectrum of broadband emitters can be cleaned up. It also demonstrates that, using a fairly simple deconvolution procedure, a factor of two enhancement in depth resolution can be achieved. An example of the enhanced resolution is shown using the signal from two microscope cover slides. C1 USN, Res Lab, Washington, DC 20375 USA. USN Acad, Annapolis, MD 21402 USA. RP Bashkansky, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 4 TC 13 Z9 13 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 1 PY 1998 VL 37 IS 34 BP 8137 EP 8138 PG 2 WC Optics SC Optics GA 141XB UT WOS:000077168600031 ER PT J AU Blank, DA Wu, C AF Blank, DA Wu, C TI Finite-time power limit for solar-radiant Ericsson engines in space applications SO APPLIED THERMAL ENGINEERING LA English DT Article DE heat engine; finite time; power; Ericsson; solar ID HEAT ENGINE AB The power output and thermal efficiency of a finite-time optimized solar-radiant Ericsson heat engine is studied. The thermodynamic model adopted is a regenerative gas Ericsson cycle coupled to a heat source and heat sink by radiant heat transfer. Both the heat source and heat sink have infinite heat capacity rates. Mathematical expressions for optimum power and the efficiency at optimum power are obtained for the cycle based on higher and lower temperature bounds. The results of this theoretical work provide a base line criteria for use in the performance evaluation and design of such engines as well as for use in performance comparisons with existing extra-terrestrial solar power plants. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Wu, C (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. NR 20 TC 23 Z9 23 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-4311 J9 APPL THERM ENG JI Appl. Therm. Eng. PD DEC PY 1998 VL 18 IS 12 BP 1347 EP 1357 DI 10.1016/S1359-4311(97)00080-X PG 11 WC Thermodynamics; Energy & Fuels; Engineering, Mechanical; Mechanics SC Thermodynamics; Energy & Fuels; Engineering; Mechanics GA 113BY UT WOS:000075530500012 ER PT J AU Mason, BD Henry, TJ Hartkopf, WI ten Brummelaar, T Soderblom, DR AF Mason, BD Henry, TJ Hartkopf, WI ten Brummelaar, T Soderblom, DR TI A multiplicity survey of chromospherically active and inactive stars SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : general; stars : activity; stars : chromospheres ID ICCD SPECKLE OBSERVATIONS; MASS-LUMINOSITY-RELATION; SOLAR-TYPE STARS; BINARY STARS; CLUSTER; TELESCOPE AB Surveys of three samples of solar-type stars, segregated by chromospheric emission level, were made to determine their multiplicity fractions and to investigate the evolution of multiplicity with age. In total, 245 stars were searched for companions with Delta V less than or equal to 3.0 and separations of 0." 035 to 1." 08 using optical speckle interferometry. By incorporating the visual micrometer survey for duplicity of the Lamont-Hussey Observatory, the angular coverage was extended to 5." 0 with no change in the Delta V limit. This magnitude difference allows mass ratios of 0.63 and larger to be detected throughout a search region of 2-127 AU for the stars observed. The 84 primaries observed in the chromospherically active sample are presumably part of a young population and are found to have a multiplicity fraction of 17.9% +/- 4.6%. The sample of 118 inactive, presumably older, primaries were selected and observed using identical methods and are found to have a multiplicity fraction of only 8.5% +/- 2.7%. Given the known link between chromospheric activity and age, these results tentatively imply a decreasing stellar multiplicity fraction from 1 to 4 Gyr, the approximate ages of the two samples. Finally, only two of the 14 very active primaries observed were found to have a companion meeting the survey detection parameters. In this case, many of the systems are either very young, or close, RS CVn type multiples that are unresolvable using the techniques employed here. C1 USN Observ, Washington, DC 20392 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Georgia State Univ, Ctr High Angular Resolut Astron, Atlanta, GA 30303 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Mason, BD (reprint author), USN Observ, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. EM bdm@draco.usno.navy.mil; thenry@recons.harvard.edu; hartkopf@chara.gsu.edu; theo@mtwilson.edu; drs@stsci.edu NR 24 TC 30 Z9 30 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 1998 VL 116 IS 6 BP 2975 EP 2983 DI 10.1086/300654 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 147RQ UT WOS:000077512000029 ER PT J AU Gunn, JE Carr, M Rockosi, C Sekiguchi, M Berry, K Elms, B de Haas, E Ivezic, Z Knapp, G Lupton, R Pauls, G Simcoe, R Hirsch, R Sanford, D Wang, S York, D Harris, F Annis, J Bartozek, L Boroski, W Bakken, J Haldeman, M Kent, S Holm, S Holmgren, D Petravick, D Prosapio, A Rechenmacher, R Doi, M Fukugita, M Shimasaku, K Okada, N Hull, C Siegmund, W Mannery, E Blouke, M Heidtman, D Schneider, D Lucinio, R Brinkman, J AF Gunn, JE Carr, M Rockosi, C Sekiguchi, M Berry, K Elms, B de Haas, E Ivezic, Z Knapp, G Lupton, R Pauls, G Simcoe, R Hirsch, R Sanford, D Wang, S York, D Harris, F Annis, J Bartozek, L Boroski, W Bakken, J Haldeman, M Kent, S Holm, S Holmgren, D Petravick, D Prosapio, A Rechenmacher, R Doi, M Fukugita, M Shimasaku, K Okada, N Hull, C Siegmund, W Mannery, E Blouke, M Heidtman, D Schneider, D Lucinio, R Brinkman, J TI The Sloan Digital Sky Survey photometric camera SO ASTRONOMICAL JOURNAL LA English DT Article DE astrometry; atlases; catalogs; cosmology : observations; instrumentation : detectors; instrumentation : photometers; surveys ID MOSAIC CAMERA; TELESCOPE; SYSTEM AB We have constructed a large-format mosaic CCD camera for the Sloan Digital Sky Survey. The camera consists of two arrays, a photometric array that uses 30 2048 x 2048 SITe/Tektroniu CCDs (24 mu m pixels) with an effective imaging area of 720 cm(2) and an astrometric array that uses 24 400 x 2048 CCDs with the same pixel size, which will allow us to tie bright astrometric standard stars to the objects imaged in the photometric camera. The instrument will be used to carry out photometry essentially simultaneously in five color bands spanning the range accessible to silicon detectors on the ground in the time-delay-and-integrate (TDI) scanning mode. The photometric detectors are arrayed in the focal plane in six columns of five chips each such that two scans cover a filled stripe 2." 5 wide. This paper presents engineering and technical details of the camera. C1 Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. USN Observ, Flagstaff, AZ 86002 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Tokyo, Sch Sci, Dept Astron, Bunkyo Ku, Tokyo 113, Japan. Natl Astron Observ, Tokyo 181, Japan. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Sci Imaging Technol Inc, Beaverton, OR USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Apache Point Observ, Sunspot, NM 88349 USA. RP Gunn, JE (reprint author), Princeton Univ, Dept Astrophys Sci, Peyton Hall, Princeton, NJ 08544 USA. NR 20 TC 1211 Z9 1213 U1 1 U2 22 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 1998 VL 116 IS 6 BP 3040 EP 3081 DI 10.1086/300645 PG 42 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 147RQ UT WOS:000077512000036 ER PT J AU Tieftrunk, AR Gaume, RA Wilson, TL AF Tieftrunk, AR Gaume, RA Wilson, TL TI High-resolution imaging of NH3 inversion lines toward W-3 main SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE ISM : abundances; ISM : individual objects : W3; ISM : molecules; radio lines : ISM ID MOLECULAR CLOUD CORE; SUBMILLIMETER OBSERVATIONS; RADIO-CONTINUUM; STAR-FORMATION; COMPLEX W3; W3(OH); REGION; EMISSION; AMMONIA; W3-IRS-5 AB Three-arcsecond angular resolution (0.03 pc at 2.3 kpc) images of the (J,K) = (1,1) and (2,2) NH3 inversion lines toward W3 Main are presented. These observations show NH3 emission from individual clumps and filaments embedded in the lower density ammonia gas, previously observed with a spatial resolution of 40 ". Toward the molecular core W3 East we detect NH3 emission with broad line profiles from a very compact (FWHM approximate to 5 ") and dense clump toward IRS 5 and weaker emission from compact clumps near IRS 11. The molecular clump toward IRS 5 is associated with a cluster of young low-mass stars and hypercompact H II regions tracing recent high-mass star formation. Toward the molecular core W3 West, which is luminous in the submillimetre but has no embedded H II continuum or NIR sources, we detect NH3 emission with narrow line profiles from a more extended (approximate to 25 ") and clumpy region. A thin NH3 filament, less than 8 " wide, stretches more than .40 " away from IRS 4, northeast of W3 West, curving around the compact H II region W3 H. Toward the ultracompact H II region W3 B we find ammonia in absorption. The VLA data presented here are in support of models which suggest that star formation seems to be occurring in bursts toward the W3 GMC. Extended NH3 emission is detected only toward a quiescent core with no associated star formation. In comparison, toward the active star-forming cores the NH3 is dispersed and under-abundant. C1 ESO La Silla, Santiago 19, Chile. USN Observ, Washington, DC 20392 USA. Max Planck Inst Radioastron, D-53121 Bonn, Germany. Univ Arizona, Steward Observ, SMTO, Tucson, AZ 85721 USA. RP Tieftrunk, AR (reprint author), ESO La Silla, Casilla 19001, Santiago 19, Chile. NR 36 TC 17 Z9 17 U1 0 U2 0 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 DEC PY 1998 VL 340 IS 1 BP 232 EP 240 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 144FK UT WOS:000077303200028 ER PT J AU Lobanov, AP Krichbaum, TP Witzel, A Kraus, A Zensus, JA Britzen, S Otterbein, K Hummel, CA Johnston, K AF Lobanov, AP Krichbaum, TP Witzel, A Kraus, A Zensus, JA Britzen, S Otterbein, K Hummel, CA Johnston, K TI VSOP imaging of S5 0836+710: a close-up on plasma instabilities in the jet SO ASTRONOMY & ASTROPHYSICS LA English DT Letter DE galaxies : active; galaxies : jets; quasars : individual : 0836+710; radio continuum : galaxies ID QUASAR AB The luminous high-redshift (z = 2.17) quasar S5 0836+710 has been observed at 5 GHz with the VSOP. We compare the properties of three images obtained from the observation: a low-resolution ground array image (dynamic range 4600:1), a full-resolution VSOP image (900:1), and an image made with only the space baselines (200:1). The space baselines alone are sufficient for a reliable recovery of the source structure, within the limits of the achieved spatial sampling of the visibility data. The curved jet ridge line observed in the images can be described by Kelvin-Helmholtz instabilities developing in a relativistic outflow with the Mach number of about 6. This description holds on the scales of less than or similar to 700 h(-1)pc, and is shown to be consistent with variable apparent speeds observed in the jet. C1 Max Planck Inst Radioastron, D-53121 Bonn, Germany. Netherlands Fdn Res Astron, NL-7990 AA Dwingeloo, Netherlands. Landessternwarte Heidelberg, D-69117 Heidelberg, Germany. USN Observ, Washington, DC 20392 USA. RP Lobanov, AP (reprint author), Max Planck Inst Radioastron, Hugel 69, D-53121 Bonn, Germany. RI Lobanov, Andrei/G-5891-2014 NR 11 TC 14 Z9 14 U1 0 U2 0 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 DEC PY 1998 VL 340 IS 2 BP L60 EP L64 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 146GU UT WOS:000077421600011 ER PT J AU Chiang, J AF Chiang, J TI Energy-dependent gamma-ray burst-peak durations and blast-wave deceleration SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; radiation mechanisms : nonthermal ID OPTICAL COUNTERPART; AFTERGLOW; MODEL AB Temporal analyses of the prompt gamma-ray and X-ray light curves of gamma-ray bursts reveal a tendency for the burst pulse timescales to increase with decreasing energy. For an ensemble of BATSE bursts, Fenimore and colleagues show that the energy dependence of burst-peak durations can be represented by Delta t proportional to E(-gamma), with gamma similar or equal to 0.4-0.45. This power-law dependence has led to the suggestion that this effect is due to radiative processes, most notably to synchrotron cooling of the nonthermal particles that produce the radiation. Here we show that a similar power-law dependence occurs, under certain assumptions, in the context of the blast-wave model and is a consequence of the deceleration of the blast wave. This effect will obtain whether or not synchrotron cooling is important, but different degrees of cooling will cause variations in the energy dependence of the peak durations. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Chiang, J (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7653, Washington, DC 20375 USA. NR 26 TC 11 Z9 11 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 752 EP 756 DI 10.1086/306451 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500032 ER PT J AU Share, GH Murphy, RJ AF Share, GH Murphy, RJ TI Accelerated and ambient He abundances from gamma-ray line measurements of flares SO ASTROPHYSICAL JOURNAL LA English DT Article DE solar wind; Sun : abundances; Sun : flares; Sun : photosphere; Sun : X-rays, gamma rays ID SOLAR-FLARE; SPECTROSCOPY; PARTICLES AB The gamma-ray lines from Be-7 and Li-7 produced when flare-accelerated He nuclei interact with ambient He have been found to be surprisingly intense from measurements made by moderate-resolution gamma-ray spectrometers on the Solar Maximum Mission (SMM) and Compton Gamma Ray Observatory (CGRO) satellites. These high intensities suggest either accelerated alpha/proton ratios greater than or similar to 0.5 and/or an He/H abundance greater than 0.1 in the subcoronal regions where the particles interact. We have studied additional gamma-ray lines in 20 flares produced by interactions of alpha particles on Fe-56 and other elements to resolve this ambiguity. These measurements indicate, on average, that the ambient He abundance is consistent with accepted photospheric values and that an enhanced concentration of He is present in flare-accelerated particles. Although there is evidence for the presence of accelerated He-3, its concentration is only a fraction of accelerated He-4. These studies also revealed a new weak line in the spectra at similar to 1.32 MeV that is attributed to an excited state of Fe-55. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Share, GH (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 13 TC 51 Z9 52 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 876 EP 884 DI 10.1086/306442 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500044 ER PT J AU Wang, YM Sheeley, NR Socker, DG Howard, RA Brueckner, GE Michels, DJ Moses, D St Cyr, OC Llebaria, A Delaboudiniere, JP AF Wang, YM Sheeley, NR Socker, DG Howard, RA Brueckner, GE Michels, DJ Moses, D St Cyr, OC Llebaria, A Delaboudiniere, JP TI Observations of correlated white-light and extreme-ultraviolet jets from polar coronal holes SO ASTROPHYSICAL JOURNAL LA English DT Article DE interplanetary medium; solar wind; Sun : corona; Sun : magnetic fields ID TELESCOPE AB Time-lapse sequences of white-light images recorded with the Large Angle Spectrometric Coronagraph (LASCO) on the Solar and Heliospheric Observatory (SOHO) frequently show long, narrow structures moving outward over the Sun's polar regions at high apparent speeds. By comparing the LASCO observations with Fe XII lambda 195 spectroheliograms made with the Extreme-ultraviolet Imaging Telescope (EIT) on SOHO between 1997 April and 1998 February, we have identified 27 correlated white-light and extreme-ultraviolet (EUV) jet events. In each case, the EUV jet was observed near the limb of the polar coronal hole 20-60 minutes before the corresponding white-light jet was registered in the coronagraph's 2-6 R. held of view. The jets originate near flaring EUV bright points and are presumably triggered by field line reconnection between magnetic bipoles and neighboring unipolar flux. The leading edges of the white-light jets propagate outward at speeds of 400-1100 km s(-1), whereas the bulk of their material travels at much lower velocities averaging around 250 km s(-1) at heliocentric distances of 2.9-3.7 R.. These lower velocities may reflect the actual outflow speeds of the background polar wind. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Lab Astrophys Spatiale, F-13376 Marseille 12, France. Inst Astrophys Spatiale, F-91405 Orsay, France. RP Wang, YM (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 15 TC 105 Z9 105 U1 1 U2 8 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 899 EP 907 DI 10.1086/306450 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500046 ER PT J AU Sterling, AC AF Sterling, AC TI Alfvenic resonances on ultraviolet spicules SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : atmosphere; Sun : chromosphere; Sun : corona; Sun : UV radiation; waves ID PERIOD CORONAL OSCILLATIONS; SOLAR ATMOSPHERE; TRANSITION REGION; FLUX TUBES; WAVES AB We consider the propagation of small-amplitude torsional Alfven waves on spicule-like structures seen at UV and EUV wavelengths. We assume that such UV spicules have densities an order of magnitude lower than chromospheric spicules. Extending the earlier analysis of Sterling & Hollweg, we find that UV spicules can act as resonance cavities, whereby Alfven waves of preferred frequencies have strong transmission into the structures. The resonance cavity forms because of the sharp changes in Alfven velocity between the photosphere/chromosphere and the UV spicule at the UV spicule's base and between the UV spicule and the corona at the top of the UV spicule. For a canonical UV spicule residing on a magnetic flux tube of strength B-0 = 40 G with length L = 10,000 km and density rho = 1.0 x 10(-14) g cm(-3), we predict a fundamental resonance period of about 35 s, some 3 times shorter than for a corresponding chromospheric spicule. Velocities along the length of the UV spicule vary from about 30 to 150 km s(-1), increasing with height along the structure. Longer UV spicules have longer resonance periods and lower rotational velocities, and stronger magnetic fields result in shorter resonance periods and higher velocities. The same qualitative parameter dependencies also hold for chromospheric spicules. Damping ftattens out the velocity amplitude's profile along the structure and reduces the maximum velocity but does not appreciably change the periods of the resonances. C1 Computat Phys Inc, Fairfax, VA 22031 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Sterling, AC (reprint author), Inst Space & Astronaut Sci, Yoshinodai 3-1-1, Kanagawa 229, Japan. EM asterling@solar.stanford.edu NR 36 TC 10 Z9 10 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 916 EP 924 DI 10.1086/306433 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500048 ER PT J AU Bautista, E Martinez, J Gagne, P AF Bautista, E Martinez, J Gagne, P TI Symptomatic venous hypertension because of occult iliofemoral deep vein thrombosis: a report of two cases SO CARDIOVASCULAR SURGERY LA English DT Article DE symptomatic venous hypertension; iliofemoral deep vein thrombosis ID POSTTHROMBOTIC-SYNDROME; SEQUELAE; RECONSTRUCTION; OBSTRUCTION; MANAGEMENT AB Two 25-year-old males with symptomatic venous hypertension (venous claudication, n = 1; swollen leg, n = 1) were evaluated for iliofemoral venous occlusive disease. One patient had a common femoral vein/external iliac vein occlusion with no history of deep vein thrombosis or trauma. The second patient had an acute deep vein thrombosis superimposed on a chronic external iliac vein stenosis. No source of extrinsic venous compression was identified in either patient. Venous reconstruction with vein bypass (patient no. 1) and vein patch angioplasty (patient no. 2) led to resolution of their hypertensive symptoms. Intraoperative examination of the involved vein segments revealed chronic changes consistent with a prior occult deep vein thrombosis in both patients. Occult iliofemoral deep vein thrombosis in young healthy males is rarely seen. The acute deep vein thrombosis may manifest minimal or no symptoms but it can lead to chronic venous occlusive disease and serious post-phlebitic morbidity. In this context, these two cases are discussed with a review of the pertinent literature. (C) 1998 The International Society for Cardiovascular Surgery. Published by Elsevier Science Ltd, All rights reserved. C1 Naval Med Ctr Portsmouth, Dept Gen Surg, Portsmouth, VA 23708 USA. Uniformed Serv Univ Hlth Sci, Dept Surg, Bethesda, MD 20814 USA. RP Gagne, P (reprint author), Naval Med Ctr Portsmouth, Dept Gen Surg, Bldg 215, Portsmouth, VA 23708 USA. NR 20 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0967-2109 J9 CARDIOVASC SURG JI Cardiovasc. Surg. PD DEC PY 1998 VL 6 IS 6 BP 598 EP 603 DI 10.1016/S0967-2109(98)00085-4 PG 6 WC Cardiac & Cardiovascular Systems; Surgery SC Cardiovascular System & Cardiology; Surgery GA 151QY UT WOS:000077733200011 PM 10395263 ER PT J AU Crook, JL Breathnach, OS Cruser, D Johnson, BE AF Crook, JL Breathnach, OS Cruser, D Johnson, BE TI Lung carcinoma metastasis at the site of central venous access SO CHEST LA English DT Article DE case report; central venous catheterization; lung neoplasm; malignant pleural effusion; non-small cell carcinoma AB Tumor metastases rarely are reported in association with central,venous catheters. The case reported herein is that of a solid tumor metastasis at the site of a previous indwelling line ipsilateral to a pleural effusion in a patient with non-small cell lung cancer. A review of the literature reveals a single case of intrathoracic malignancy seeding at the site of a central venous catheter, Other investigators are urged to collect information about the development of tumor implants at the site of catheter insertion in patients with cancer and pleural effusions to further define the extent of the problem. C1 USN, Med Branch, Natl Naval Med Ctr, Dept Med & Pathol,Div Clin Sci,NCI, Bethesda, MD 20889 USA. RP Johnson, BE (reprint author), USN, Med Branch, Natl Naval Med Ctr, Dept Med & Pathol,Div Clin Sci,NCI, Bldg 8,Room 5101,8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU AMER COLL CHEST PHYSICIANS PI NORTHBROOK PA 3300 DUNDEE ROAD, NORTHBROOK, IL 60062-2348 USA SN 0012-3692 J9 CHEST JI Chest PD DEC PY 1998 VL 114 IS 6 BP 1772 EP 1774 DI 10.1378/chest.114.6.1772 PG 3 WC Critical Care Medicine; Respiratory System SC General & Internal Medicine; Respiratory System GA 149PF UT WOS:000077613600045 PM 9872218 ER PT J AU Rollwagen, FM Yu, ZY Li, YY Pacheco, ND AF Rollwagen, FM Yu, ZY Li, YY Pacheco, ND TI IL-6 rescues enterocytes from hemorrhage induced apoptosis in vivo and in vitro by a bcl-2 mediated mechanism SO CLINICAL IMMUNOLOGY AND IMMUNOPATHOLOGY LA English DT Article DE hemorrhage; apoptosis; IL-6; oral cytokine ID CELL-DEATH; ORAL INTERLEUKIN-6; PROTEIN-SYNTHESIS; EPITHELIAL-CELLS; SMALL-INTESTINE; NEURONAL DEATH; EXPRESSION; SHOCK; RAT; MACROPHAGES AB Following a hemorrhagic event, damage to the highly metabolic intestinal tissue induces loss of barrier function leading to bacterial escape and LPS contamination of the host. Orally administered IL-6 restores intestinal barrier function following hemorrhage in both rat and mouse models, IL-6 prevents apoptosis in a variety of lymphoid cells and lines, through the activation of the proto-oncogene bcl-2. This communication elucidates the role of the IL-6-bcl-2 interaction in intestinal apoptosis following hemorrhagic shock. Terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling (TUNEL) and p53 immunohistochemical staining were used to examine intestines from mice hemorrhaged and fed saline or IL-6 and enterocytes (IEC-6) exposed to hypoxia and LPS alone or LPS and IL-6 in vitro. bt situ hybridization for bcl-2 expression was performed on intestines or enterocytes, Intestinal sections from mice hemorrhaged and fed IL-6 showed reduction in apoptosis and increases in bcl-2 gene expression relative to sections taken from mice hemorrhaged and fed saline. IEC-6 cells exposed to hypoxia and LPS had high numbers of TUNEL staining cells. Subsequent exposure to IL-6 after hypoxia and LPS reduced apoptotic cell numbers and increased bcl-2 gene expression, The data show that exposure of intestinal epithelial cells to IL-6 either by oral administration in hemorrhaged mice or by coculture following hypoxia and LPS treatment results in increased bcl-2 gene expression and reduced damage from apoptosis. (C) 1998 Academic Press. C1 Uniformed Serv Univ Hlth Sci, Dept Pathol, Bethesda, MD 20814 USA. Henry M Jackson Fdn, Rockville, MD 20852 USA. USN, Med Res Inst, Wound Repair Enhancement Program, Bethesda, MD 20882 USA. RP Rollwagen, FM (reprint author), Uniformed Serv Univ Hlth Sci, Dept Pathol, 4301 Jones Bridge Rd, Bethesda, MD 20814 USA. EM frollag@usuhs.mil NR 31 TC 40 Z9 41 U1 0 U2 4 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0090-1229 J9 CLIN IMMUNOL IMMUNOP JI Clin. Immunol. Immunopathol. PD DEC PY 1998 VL 89 IS 3 BP 205 EP 213 DI 10.1006/clin.1998.4600 PG 9 WC Immunology; Pathology SC Immunology; Pathology GA 149LH UT WOS:000077606400003 PM 9837690 ER PT J AU Turton, DB Silverman, ED Shakir, KMM AF Turton, DB Silverman, ED Shakir, KMM TI Time interval between the last dose of propylthiouracil and I-131 therapy influences cure rates in hyperthyroidism caused by Graves' disease SO CLINICAL NUCLEAR MEDICINE LA English DT Article DE Graves' disease; propylthiouracil; radioiodine; thyrotoxicosis ID IODINE AB Purpose: To examine the effects of propylthiouracil (PTU) pretreatment on the outcome of initial I-131 therapy for Graves' disease. Design: A retrospective chart review was done. Patients and Methods: The authors studied 106 patients in an outpatient nuclear medicine setting who were given initial I-131 therapy for Graves' disease from September 1989 to March 1993 and followed for at least 6 months after therapy. These patients were divided into groups based on whether they had ever received PTU or, if they had received PTU, the length of time between the last dose of PTU and the I-131 therapy dose. Measured failure rates of initial I-131 therapy were based on recurrent or continued hyperthyroidism. Results: Treatment failure rates increased markedly from 2.5% in non-PTU-treated patients (n = 80) to 23.1% (n = 26) in patients pretreated with PTU (P = 0.003). Although not significant, two PTU-pretreated subgroups showed a trend toward increased failure rates. The failure rate was 15.4% (n = 13) in patients whose last dose of PTU was 7-14 days before I-131 therapy, and it increased further to 30.8% (n = 13) in patients whose last dose of PTU was within 1 week of I-131 therapy. Conclusions: PTU pretreatment within 2 weeks of I-131 treatment is a strong independent risk factor in failure rates after initial I-131 therapy in patients with Graves' disease. Patients should be free of PTU for 2 weeks before I-131 therapy if they are able to tolerate it, otherwise the dose of I-131 may need to be adjusted upward to diminish the risk that the initial I-131 therapy will fail. C1 USN, Dept Radiol, Div Nucl Med, Natl Naval Med Ctr, Bethesda, MD 20889 USA. USN, Natl Naval Med Ctr, Dept Internal Med, Bethesda, MD 20889 USA. RP Turton, DB (reprint author), USN, Dept Radiol, Div Nucl Med, Natl Naval Med Ctr, Bethesda, MD 20889 USA. NR 7 TC 12 Z9 15 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0363-9762 J9 CLIN NUCL MED JI Clin. Nucl. Med. PD DEC PY 1998 VL 23 IS 12 BP 810 EP 814 DI 10.1097/00003072-199812000-00004 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 144ZP UT WOS:000077346500004 PM 9858291 ER PT J AU Fuqua, JS Berkovitz, GD AF Fuqua, JS Berkovitz, GD TI Growth hormone excess in a child with neurofibromatosis type 1 and optic pathway tumor: A patient report SO CLINICAL PEDIATRICS LA English DT Article C1 USN, Med Ctr, Dept Pediat, San Diego, CA 92134 USA. Johns Hopkins Univ, Sch Med, Dept Pediat, Div Pediat Endocrinol, Baltimore, MD 21205 USA. RP Fuqua, JS (reprint author), USN, Med Ctr, Dept Pediat, San Diego, CA 92134 USA. NR 9 TC 12 Z9 12 U1 0 U2 0 PU WESTMINSTER PUBL INC PI GLEN HEAD PA 708 GLEN COVE AVE, GLEN HEAD, NY 11545 USA SN 0009-9228 J9 CLIN PEDIATR JI Clin. Pediatr. PD DEC PY 1998 VL 37 IS 12 BP 749 EP 752 DI 10.1177/000992289803701207 PG 4 WC Pediatrics SC Pediatrics GA 147XH UT WOS:000077522500007 PM 9864651 ER PT J AU Roberts, JC Bao, G White, GJ AF Roberts, JC Bao, G White, GJ TI Experimental, numerical and analytical results for bending and buckling of rectangular orthotropic plates SO COMPOSITE STRUCTURES LA English DT Article DE composites; bending; buckling; analysis; FEA AB Solid unstiffened, sandwich and hat-stiffened rectangular orthotropic fiber reinforced plastic (FRP) plates were tested for buckling by in-plane compression and for stresses and deflections under uniform out-of-plane pressure. The solid unstiffened and hat-stiffened plates were 154 x 77 cm (1 x w) (72 x 36 in), while the sandwich plates were 102 x 77 cm (Ix w) (48 x 36 in). Balsa core was used in the sandwich plates and in the hat-stiffeners. The two short edges of the unstiffened and sandwich plates were clamped, while the two long edges were simply supported. The two long edges of the hat-stiffened plates were free, while the short edges were clamped. The buckling load, as well as stresses and deflections from the tests, were then compared to those from finite element analysis (FEA) and analytic solutions. There was reasonably good agreement between FEA, analytic, and experimental buckling stresses for the unstiffened solid plates. There was reasonable agreement in buckling stresses between FEA and experimental results for the hat-stiffened plate. There was poor agreement between FEA, analytic, and experimental elastic buckling results for the sandwich plates because they failed in local buckling prior to global buckling. Under out-of-plane uniform pressure, FEA and analytic solutions of the stresses and deflections for the unstiffened solid plates agreed well with experimental results. There was poor agreement between FEA and experimental results for stresses and deflections of the hat-stiffened or sandwich plates. Experimental error could be traced, in part,to plate fabrication, the method of applying out-of-plane pressure, edge support, and instrumentation accuracy. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Johns Hopkins Univ, Appl Phys Lab, Baltimore, MD 20723 USA. Dept Engn Mech, Baltimore, MD 20723 USA. USN Acad, Annapolis, MD 21402 USA. RP Roberts, JC (reprint author), Johns Hopkins Univ, Appl Phys Lab, 11100 Johns Hopkins Rd, Baltimore, MD 20723 USA. EM jack_roberts@jhuapl.edu RI Roberts, Jack/A-6660-2009 NR 15 TC 3 Z9 4 U1 2 U2 8 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 DEC PY 1998 VL 43 IS 4 BP 289 EP 299 DI 10.1016/S0263-8223(98)00112-3 PG 11 WC Materials Science, Composites SC Materials Science GA 175DP UT WOS:000079077800003 ER PT J AU Irvine, CE Chin, SK Frincke, D AF Irvine, CE Chin, SK Frincke, D TI Integrating security into the curriculum SO COMPUTER LA English DT Article AB An educational system that cultivates an appropriate knowledge of computer security will increase the likelihood that the next generation of IT workers will have the background needed to design and develop systems that are engineered to be reliable and secure. The technical aspects of security are closely related to computer science and engineering. And many of the goals, concepts, and reasoning techniques are similar too. Thus, two approaches are possible: Computer security could be the focus of the curriculum, which would investigate the foundations and technical approaches to security in considerable depth. A computer science or computer engineering curriculum could choose to use computer security as an important property to be addressed in all coursework. The authors argue that it is not reasonable to suggest that every student should learn everything about security. Instead, they propose an approach that matches appropriate knowledge and skills with typical roles in the information society. In this way, security insights can be integrated within the existing information systems programs, rather than be treated separately. This article, therefore, proposes a set of high-level educational objectives as the basis of a security-enhanced curriculum. C1 USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93940 USA. USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA USA. USN, Postgrad Sch, Ctr INFOSEC Studies & Res, Monterey, CA USA. Syracuse Univ, Dept Elect Engn & Comp Sci, Syracuse, NY 13244 USA. Univ Idaho, Dept Comp Sci, Moscow, ID 83843 USA. RP Irvine, CE (reprint author), USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93940 USA. NR 10 TC 10 Z9 10 U1 0 U2 3 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0018-9162 J9 COMPUTER JI Computer PD DEC PY 1998 VL 31 IS 12 BP 25 EP + DI 10.1109/2.735847 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA 141WX UT WOS:000077168200010 ER PT J AU Rowe, NC Schiavo, S AF Rowe, NC Schiavo, S TI An intelligent tutor for intrusion detection on computer systems SO COMPUTERS & EDUCATION LA English DT Article AB Intrusion detection is the process of identifying unauthorized usage of a computer system. It is an important skill for computer-system administrators. It is difficult to learn on the job because it is needed only occasionally but can be critical. We describe a tutor incorporating two programs. The first program uses artificial-intelligence planning methods to generate realistic audit files reporting actions of a variety of simulated users (including intruders) of a Unix computer system. The second program simulates the system afterwards, and asks the student to inspect the audit and fix the problems caused by the intruders. This program uses intrusion-recognition rules to itself infer the problems, planning methods to figure how best to fix them, plan-inference methods to track student actions, and tutoring rules to tutor intelligently. Experiments show that students using the tutor learn a significant amount in a short time. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. RP Rowe, NC (reprint author), USN, Postgrad Sch, Dept Comp Sci, Code CS-Rp, Monterey, CA 93943 USA. NR 13 TC 7 Z9 7 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-1315 J9 COMPUT EDUC JI Comput. Educ. PD DEC PY 1998 VL 31 IS 4 BP 395 EP 404 DI 10.1016/S0360-1315(98)00049-9 PG 10 WC Computer Science, Interdisciplinary Applications; Education & Educational Research SC Computer Science; Education & Educational Research GA 147BE UT WOS:000077467400004 ER PT J AU Richardson, MD Davis, AM AF Richardson, MD Davis, AM TI Modeling gassy sediment structure and behavior - Introduction SO CONTINENTAL SHELF RESEARCH LA English DT Editorial Material C1 USN, Marine Geosci Div, Res Lab, Stennis Space Ctr, MS 39529 USA. Univ Wales, Sch Ocean Sci, Menai Bridge LL59 5EY, Gwynedd, Wales. RP Richardson, MD (reprint author), USN, Marine Geosci Div, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD DEC PY 1998 VL 18 IS 14-15 BP 1669 EP 1669 PG 1 WC Oceanography SC Oceanography GA 155NM UT WOS:000077953300001 ER PT J AU Richardson, MD Davis, AM AF Richardson, MD Davis, AM TI Modeling methane-rich sediments of Eckernforde Bay SO CONTINENTAL SHELF RESEARCH LA English DT Article ID MUDDY SEDIMENTS; GASSY SEDIMENTS; BALTIC SEA; BACKSCATTERING; ENVIRONMENTS; VARIABILITY; PROFILES; BUBBLES; LAYER AB Methane gas bubbles, generated by biochemical processes, are ubiquitous in the organic-rich, muddy sediments of coastal waters and shallow adjacent seas. Seismic surveys have provided considerable information on the spatial distribution of these gassy sediments. The basic biogeochemical processes responsible for methane generation and consumption are well known and models of acoustic and mechanical behavior of gassy sediments have been developed and tested under laboratory conditions. In spite of the considerable past effort, methane bubble distribution and concentration and the resultant sediment behavior have remained unpredictable prior to the studies described herein. This special issue of Continental Shelf Research describes the results of joint US/German led experiments designed to physically characterize and model the effects of benthic boundary layer processes on seafloor structure, properties, and behavior in the gassy sediments of Eckernforde Bay, Baltic Sea. Spatial and temporal distribution of the acoustic turbidity horizon, methane concentration, and the volume, size, shape, and distribution of bubbles are described for the first time. A kinetic model of the complex biochemical interactions of bacterial methane production and consumption, advective and diffusive transport processes, organic supply, and sedimentation rates has successfully been used to predict methane and sulfate concentration profiles, rates of biogeochemical reactions, and gas volumes. The spatial distribution and strength of acoustic turbidity is accurately predicted by these biochemical models, whereas the seasonal migration of the acoustic turbidity horizon correlates with changes in sediment temperature and is modeled using methane solubility. Short-term ebullition of methane from the sediment surface correlates with rapid change in bottom pressure or an increase in hydraulic flow from subbottom aquifers. Fine-scale characterization of bubble volume, shape, and size distribution coupled with concomitant in situ measurement of sound speed, attenuation, and scattering strength has allowed validation of frequency dependent acoustic scattering and propagation models. Eckernforde Bay is without doubt the most studied and well-understood area of gassy sediments and as such provides a 'natural laboratory' for future studies. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Wales, Sch Ocean Sci, Menai Bridge LL59 5EY, Gwynedd, Wales. USN, Marine Geosci Div, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Davis, AM (reprint author), Univ Wales, Sch Ocean Sci, Menai Bridge LL59 5EY, Gwynedd, Wales. NR 78 TC 11 Z9 11 U1 2 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD DEC PY 1998 VL 18 IS 14-15 BP 1671 EP 1688 PG 18 WC Oceanography SC Oceanography GA 155NM UT WOS:000077953300002 ER PT J AU Wilkens, RH Richardson, MD AF Wilkens, RH Richardson, MD TI The influence of gas bubbles on sediment acoustic properties: in situ, laboratory, and theoretical results from Eckernforde Bay, Baltic sea SO CONTINENTAL SHELF RESEARCH LA English DT Article ID SHALLOW GAS; VARIABILITY; MODEL; SOILS AB Acoustic turbidity caused by the presence of gas bubbles in seafloor sediments is a common occurrence worldwide, but is as pet poorly understood. The Coastal Benthic Boundary Layer experiment in the Baltic off northern Germany was planned to better characterize the acoustic response of a bubbly sediment horizon, In this context, in situ measurements of compressional wave speed and attenuation were made over the frequency range of 5-400 kHz in gassy sediments of Eckernforde Bay. Dispersion of compressional speed data was used to determine the upper limit of the frequency of methane bubble resonance at between 20 and 25 kHz. These data, combined with bubble size distributions determined from CT scans of sediments in cores retained at ambient pressure, yield estimates of effective bubble sizes of 0.3-5.0 mm equivalent radius. The highly variable spatial distribution of bubble volume and bubble size distribution is used to reconcile the otherwise contradictory frequency-dependent speed and attenuation data with theory. At acoustic frequencies above resonance (>25 kHz) compressional speed is unaffected by bubbles and scattering from bubbles dominates attenuation. Al frequencies below resonance (<1 kHz) 'compressibility effects' dominate, speed is much lower (250 m s(-1)) than bubble-free sediments, and attenuation is dominated by scattering from impedance contrasts. Between 1.5 and 25 kHz bubble resonance greatly affects speed and attenuation. Compressional speed in gassy sediments (1100-1200 m s(-1)) determined at 5-15 kHz is variable and higher than predicted by theory (<250 m s(-1)). These higher measured speeds result from two factors: speeds are an average of lower speeds in gassy sediments and higher speeds in bubble-free sediments; and the volume of smaller-sized bubbles which contribute to the lower observed speeds is much lower than total gas volume. The frequency-dependent acoustic propagation is further complicated as the mixture of bubble sizes selectively strips energy near bubble resonance frequencies (very high attenuation) allowing lower and higher frequency energy to propagate. It was also demonstrated that acoustic characterization of gassy sediments can be used to define bubble size distribution and fractional volume. (C) 1998 Elsevier Science Ltd, All rights reserved. C1 Univ Hawaii Manoa, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. USN, Marine Geosci Div, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Wilkens, RH (reprint author), Univ Hawaii Manoa, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. NR 38 TC 59 Z9 61 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD DEC PY 1998 VL 18 IS 14-15 BP 1859 EP + DI 10.1016/S0278-4343(98)00061-2 PG 32 WC Oceanography SC Oceanography GA 155NM UT WOS:000077953300010 ER PT J AU Briggs, KB Jackson, PD Holyer, RJ Flint, RC Sandidge, JC Young, DK AF Briggs, KB Jackson, PD Holyer, RJ Flint, RC Sandidge, JC Young, DK TI Two-dimensional variability in porosity, density, and electrical resistivity of Eckernforde Bay sediment SO CONTINENTAL SHELF RESEARCH LA English DT Article ID ACOUSTIC SCATTERING; SEA-FLOOR AB Image-based analysis techniques are employed to compare sediment density heterogeneity as interpreted from X-radiography and electrical resistivity measurements; Assessments of sediment heterogeneity in two dimensions through the use of the two methods, with some exceptions, yield similar results. Autocorrelation functions estimated from density fluctuations reveal an anisotropy between vertical and horizontal sediment structure indicated by horizontal correlation lengths being greater than vertical correlation lengths. In addition to the anisotropy, discrepancies between values of correlation lengths calculated from two statistical methods are indicative of the scale-dependent nature of the sediment structure. This scale dependence is also exemplified by the differences between the images of X-radiography and electrical resistivity. The unequal volume of sediment over which the respective methods are integrated produces results differing by the amount and type of information included in each image. Electrical microresistivity is more sensitive than X-radiography to many smaller-scale variations in sediment density. Combining the results from X-radiography and microresistivity imaging allows the calculation of Archie's rn parameter, an extremely sensitive indicator of sediment microstructure. In addition, electrical microresistivity gives a measurement of sediment tortuosity coincident with sediment porosity and density. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. British Geol Survey, Engn Geol & Geophys Grp, Nottingham NG12 5GG, England. RP Briggs, KB (reprint author), USN, Res Lab, Code 7431, Stennis Space Ctr, MS 39529 USA. NR 31 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 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD DEC PY 1998 VL 18 IS 14-15 BP 1939 EP 1964 DI 10.1016/S0278-4343(98)00064-8 PG 26 WC Oceanography SC Oceanography GA 155NM UT WOS:000077953300013 ER PT J AU Lang, AR Makepeace, APW Butler, JE AF Lang, AR Makepeace, APW Butler, JE TI Synchrotron X-ray microdiffraction measurements of lattice tilts within CVD diamond crystallites terminated by cathodoluminescent blue-cross-quartered cube facets SO DIAMOND AND RELATED MATERIALS LA English DT Article DE X-ray microradiography; X-ray microdiffraction; surface profilometry; lattice misorientations; diamond films; characterization; columnar growth ID DIFFRACTION AB A [001]-textured microwave plasma CVD diamond film contains crystallites with large square (001) facets, edge lengths up to similar to 100 mu m, that have attracted attention because of an unusual highly symmetric step pattern on these (001) facets. This pattern consists of arrays of steps (heights in the 10-20-nm range) facing inwards from the facet corners towards the facet centre, thereby dividing the facet surface into quadrants with a rough mirror symmetry in (110) and (1 (1) over bar 0); and these dividing mirror planes are also loci of blue-violet cathodoluminescent emission, the "Blue-Cross". The present work has applied synchrotron X-ray microradiography as a high-contrast imaging technique for displaying size and habit distribution in the crystallite population, and microdiffraction and topography for measuring misorientations within chosen individual crystallites. Studies of the microscopically observed step patterns, surface tilt profiles and X-ray diffraction pattern fine structure are detailed for two crystallites, one being in the largest size bracket, facet diameter 91 mu m, and the other of a more common size, facet diameter 53 mu m. X-ray diffraction data corroborated and amplified findings made in previous work by electron channelling patterns. The X-ray diffraction patterns strikingly demonstrated that the crystal lattice under the (001) facet has a fourfold split, the normals to the (001) lattice planes in each quadrant being tilted outward towards the facet corner cube direction of the quadrant concerned. Approximate values of the mean outward tilt of the quadrants, relative to the mean [001] axis of the crystallite, were 0.85 degrees in the larger crystallite and 0.4 degrees in the smaller crystallite. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. USN, Res Lab, Washington, DC 20375 USA. RP Lang, AR (reprint author), Univ Bristol, HH Wills Phys Lab, Tyndall Ave, Bristol BS8 1TL, Avon, England. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 6 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD DEC PY 1998 VL 7 IS 11-12 BP 1698 EP 1708 DI 10.1016/S0925-9635(98)00250-7 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 149QR UT WOS:000077617300017 ER PT J AU Connell, SH Sellschop, JPF Butler, JE Maclear, RD Doyle, BP Machi, IZ AF Connell, SH Sellschop, JPF Butler, JE Maclear, RD Doyle, BP Machi, IZ TI A study of the mobility and trapping of minor hydrogen concentrations in diamond in three dimensions using quantitative ERDA microscopy SO DIAMOND AND RELATED MATERIALS LA English DT Article DE CVD diamond; natural diamond; HPHT diamond; ERDA; TDPAD; hydrogen ID CVD AB Two direct and two indirect nuclear methods are used for the analysis of hydrogen in diamond of different types. Exploiting the power of two-dimensional position sensitive detectors, the distribution of hydrogen in and on diamond in three dimensions has been measured by elastic recoil detection analysis, supplementing the earlier resonant nuclear techniques. Indirect methods of muonium spin relation and time differential perturbed angular distribution measurements prove to be very informative. In a series of dynamic experiments, hydrogen has been implanted and the diffusion thereof sought as a function of temperature. Unlike the equivalent case for silicon, no migration of the hydrogen in diamond is found up to 1473 K. This striking result is considered in regard to existing theoretical calculations. It is concluded that the implanted hydrogen is self-trapped. Arguments are presented as to the location of hydrogen in natural diamond, in diamond grown at high pressure and high temperature, and in diamond grown by chemical vapour deposition. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Witwatersrand, Schonland Res Ctr Nucl Sci, Johannesburg, South Africa. Univ Durban Westville, Dept Phys, ZA-4000 Durban, South Africa. RP Butler, JE (reprint author), USN, Res Lab, Code 6174, Washington, DC 20375 USA. EM butler@ccf.nrl.navy.mil RI Butler, James/B-7965-2008; Connell, Simon/F-2962-2015 OI Butler, James/0000-0002-4794-7176; Connell, Simon/0000-0001-6000-7245 NR 15 TC 19 Z9 21 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD DEC PY 1998 VL 7 IS 11-12 BP 1714 EP 1718 DI 10.1016/S0925-9635(98)00266-0 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 149QR UT WOS:000077617300019 ER PT J AU Wu, AS Banzhaf, W AF Wu, Annie S. Banzhaf, Wolfgang TI Introduction to the Special Issue: Variable-Length Representation and Noncoding Segments for Evolutionary Algorithms SO EVOLUTIONARY COMPUTATION LA English DT Editorial Material C1 [Wu, Annie S.] USN, Res Lab, Washington, DC 20375 USA. [Banzhaf, Wolfgang] Univ Dortmund, Dept Comp Sci, D-44221 Dortmund, Germany. RP Wu, AS (reprint author), USN, Res Lab, Code 5514, Washington, DC 20375 USA. EM aswu@aic.nrl.navy.mil; banzhaf@cs.uni-dortmund.de NR 22 TC 6 Z9 6 U1 0 U2 0 PU MIT PRESS PI CAMBRIDGE PA 55 HAYWARD STREET, CAMBRIDGE, MA 02142 USA SN 1063-6560 J9 EVOL COMPUT JI Evol. Comput. PD WIN PY 1998 VL 6 IS 4 SI SI BP III EP VI DI 10.1162/evco.1998.6.4.iii PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA V21ZK UT WOS:000208245300001 PM 10030465 ER PT J AU Burke, DS De Jong, KA Grefenstette, JJ Ramsey, CL Wu, AS AF Burke, Donald S. De Jong, Kenneth A. Grefenstette, John J. Ramsey, Connie Loggia Wu, Annie S. TI Putting More Genetics into Genetic Algorithms SO EVOLUTIONARY COMPUTATION LA English DT Article DE Models of viral evolution; variable-length representation; length penalty functions; genome length adaptation; noncoding regions; duplicative genes AB The majority of current genetic algorithms (GAS), while inspired by natural evolutionary systems, are seldom viewed as biologically plausible models. This is not a criticism of GAS, but rather a reflection of choices made regarding the level of abstraction at which biological mechanisms are modeled, and a reflection of the more engineering-oriented goals of the evolutionary computation community. Understanding better and reducing this gap between GAS and genetics has been a central issue in an interdisciplinary project whose goal is to build GA-based computational models of viral evolution. The result is a system called Virtual Virus (VIV). VIV incorporates a number of more biologically plausible mechanisms, including a more flexible genotype-to-phenotype mapping. In VIV the genes are independent of position, and genomes can vary in length and may contain noncoding regions, as well as duplicative or competing genes. Initial computational studies with VIV have already revealed several emergent phenomena of both biological and computational interest. In the absence of any penalty based on genome length, VIV develops individuals with long genomes and also performs more poorly (from a problem-solving viewpoint) than when a length penalty is used. With a fixed linear length penalty, genome length tends to increase dramatically in the early phases of evolution and then decrease to a level based on the mutation rate. The plateau genome length (ie., the average length of individuals in the final population) generally increases in response to an increase in the base mutation rate. When VIV converges, there tend to be many copies of good alternative genes within the individuals. We observed many instances of switching between active and inactive genes during the entire evolutionary process. These observations support the conclusion that noncoding regions serve as scratch space in which VIV can explore alternative gene values. These results represent a positive step in understanding how GAS might exploit more of the power and flexibility of biological evolution while simultaneously providing better tools for understanding evolving biological systems. C1 [Burke, Donald S.] Johns Hopkins Univ, Sch Hyg & Publ Hlth, Ctr Immunizat Res, Baltimore, MD 21205 USA. [De Jong, Kenneth A.] George Mason Univ, Dept Comp Sci, Fairfax, VA 22030 USA. [Grefenstette, John J.] George Mason Univ, Inst Biosci Bioinformat & Biotechnol, Manassas, VA 20110 USA. [Ramsey, Connie Loggia; Wu, Annie S.] USN, Navy Ctr Appl Res Artificial Intelligence, Res Lab, Washington, DC 20375 USA. RP Burke, DS (reprint author), Johns Hopkins Univ, Sch Hyg & Publ Hlth, Ctr Immunizat Res, 615 N Wolfe St, Baltimore, MD 21205 USA. EM dburke@jhsph.edu; kdejong@gmu.edu; gref@ib3.gmu.edu; ramsey@aic.nrl.navy.mil; aswu@aic.nrl.navy.mil OI /0000-0002-5704-8094 FU Office of Naval Research,; National Research Council; Walter Reed Army Institute of Research FX This work is supported by the Office of Naval Research, the National Research Council, and the Walter Reed Army Institute of Research. NR 31 TC 38 Z9 38 U1 1 U2 4 PU MIT PRESS PI CAMBRIDGE PA 55 HAYWARD STREET, CAMBRIDGE, MA 02142 USA SN 1063-6560 J9 EVOL COMPUT JI Evol. Comput. PD WIN PY 1998 VL 6 IS 4 SI SI BP 387 EP 410 DI 10.1162/evco.1998.6.4.387 PG 24 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA V21ZK UT WOS:000208245300006 PM 10030470 ER PT J AU Fetrow, FM AF Fetrow, FM TI Cullen's 'Yet Do I Marvel' SO EXPLICATOR LA English DT Article C1 USN Acad, Annapolis, MD USA. RP Fetrow, FM (reprint author), USN Acad, Annapolis, MD USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU HELDREF PUBLICATIONS PI WASHINGTON PA 1319 EIGHTEENTH ST NW, WASHINGTON, DC 20036-1802 USA SN 0014-4940 J9 EXPLICATOR JI Explicator PD WIN PY 1998 VL 56 IS 2 BP 103 EP 105 PG 3 WC Literature SC Literature GA YY557 UT WOS:000072160100020 ER PT J AU Loncarich, DP Clapper, M AF Loncarich, DP Clapper, M TI Dislocation of posterior tibial tendon SO FOOT & ANKLE INTERNATIONAL LA English DT Article AB Dislocation of the posterior tibial tendon has been reported rarely in the English literature. We report a case of traumatic dislocation of the posterior tibial tendon. The diagnosis was delayed for months and was ultimately made by magnetic resonance imaging, which accurately determined the location of the tendon. At the time of surgical exploration, no predisposing anatomic abnormalities were noted. A new pseudoretinaculum had developed that prevented recurrent subluxation or dislocation. Surgical relocation of the tendon and repair of the retinaculum resulted in a good outcome. C1 USN, Med Ctr, San Diego, CA 92134 USA. RP Loncarich, DP (reprint author), USN, Med Ctr, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 13 TC 7 Z9 7 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1071-1007 J9 FOOT ANKLE INT JI Foot Ankle Int. PD DEC PY 1998 VL 19 IS 12 BP 821 EP 824 PG 4 WC Orthopedics SC Orthopedics GA 149GK UT WOS:000077596600005 PM 9872468 ER PT J AU Frohlich, C Lean, J AF Frohlich, C Lean, J TI The Sun's total irradiance: Cycles, trends and related climate change uncertainties since 1976 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TOTAL SOLAR IRRADIANCE; SOLAR-CYCLE-22; VARIABILITY; LUMINOSITY; INDEX AB A composite record of the Sun's total irradiance compiled from measurements made by five independent space-based radiometers since 1978 exhibits a prominent 11-year cycle with similar levels during 1986 and 1996, the two most recent minimum epochs of solar activity. This finding contradicts recent assertions of a 0.04% irradiance increase from the 1986 to 1996 solar minima and suggests that solar radiative output trends contributed little of the 0.2 degrees C increase in the global mean surface temperature in the past decade. Nor does our 18-year composite irradiance record support a recent upward irradiance trend inferred from solar cycle length, a parameter used to imply a close linkage in the present century between solar variability and climate change. C1 Phys Meteorol Observ Davos, World Radiat Ctr, CH-7260 Davos Dorf, Switzerland. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Frohlich, C (reprint author), Phys Meteorol Observ Davos, World Radiat Ctr, Dorfstr 33, CH-7260 Davos Dorf, Switzerland. NR 26 TC 308 Z9 312 U1 3 U2 19 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 DEC 1 PY 1998 VL 25 IS 23 BP 4377 EP 4380 DI 10.1029/1998GL900157 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 143XG UT WOS:000077282400036 ER PT J AU Bowers, CA Jentsch, F Salas, E Braun, CC AF Bowers, CA Jentsch, F Salas, E Braun, CC TI Analyzing communication sequences for team training needs assessment SO HUMAN FACTORS LA English DT Article ID COORDINATION; PERFORMANCE AB Several models of team performance have suggested that a clearer understanding of team process is needed to determine better training formats and reduce crew-generated errors. The present study investigated the degree to which analyzing communication sequences would contribute to the understanding of effective crew process in two simulated night tasks. The results indicate that pattern analyses reveal additional strong differences between performance groups that would have been overlooked by simple frequency counts of communication. In each case, the sequential analysis shed additional light on the communication patterns that characterize better-performing teams. These results are discussed in terms of their implications for team performance research and team training. Potential applications of this research include training needs assessment, training design, and performance measurement after training. C1 Univ Cent Florida, Dept Psychol, Orlando, FL 32816 USA. USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. Univ Idaho, Moscow, ID 83843 USA. RP Bowers, CA (reprint author), Univ Cent Florida, Dept Psychol, Orlando, FL 32816 USA. NR 21 TC 61 Z9 61 U1 0 U2 13 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0018-7208 J9 HUM FACTORS JI Hum. Factors PD DEC PY 1998 VL 40 IS 4 BP 672 EP 679 DI 10.1518/001872098779649265 PG 8 WC Behavioral Sciences; Engineering, Industrial; Ergonomics; Psychology, Applied; Psychology SC Behavioral Sciences; Engineering; Psychology GA 161KK UT WOS:000078287700012 ER PT J AU Bowers, CA Jentsch, F AF Bowers, CA Jentsch, F TI On learning to play with other kids' toys: A response to Sanderson and Benda SO HUMAN FACTORS LA English DT Article AB In their critique of our research, Sanderson and Benda (1998, this issue) suggest several concerns with our characterization and utilization of the Exploratory Sequential Data Analysis (ESDA) approach. In this response, we consider each of the concerns in the context of training needs analysis. We conclude that the ESDA framework appears to hold promise as a training needs analysis tool. However further dialogue between the experts in the ESDA approach and those in training is required to realize this potential. C1 Univ Cent Florida, Dept Psychol, Team Performance Lab, Orlando, FL 32816 USA. USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. RP Bowers, CA (reprint author), Univ Cent Florida, Dept Psychol, Team Performance Lab, POB 161390, Orlando, FL 32816 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU HUMAN FACTORS SOC PI SANTA MONICA PA BOX 1369, SANTA MONICA, CA 90406 USA SN 0018-7208 J9 HUM FACTORS JI Hum. Factors PD DEC PY 1998 VL 40 IS 4 BP 685 EP 687 DI 10.1518/001872098779649364 PG 3 WC Behavioral Sciences; Engineering, Industrial; Ergonomics; Psychology, Applied; Psychology SC Behavioral Sciences; Engineering; Psychology GA 161KK UT WOS:000078287700014 ER PT J AU Allan, N Trizna, DB McLaughlin, DJ AF Allan, N Trizna, DB McLaughlin, DJ TI Numerical comparison of techniques for estimating Doppler velocity time series from coherent sea surface scattering measurements SO IEE PROCEEDINGS-RADAR SONAR AND NAVIGATION LA English DT Article ID INSTANTANEOUS FREQUENCY; MICROWAVE BACKSCATTER; RADAR MEASUREMENTS; GRAZING ANGLES; BREAKING WAVES AB A number of techniques for estimating: the Doppler velocity time series from coherent sea surface scattering measurements are compared by observing their behaviour with computer simulated signals. These techniques include the finite difference instantaneous frequency estimator, the covariance moment estimation technique, tracking the peak of the short-time Fourier transform and tracking the peak of the cross Wigner-Ville time-frequency distribution. This comparison is achieved by examining the ability of each technique to track the instantaneous frequency of a unity amplitude. sinusoidal frequency law, complex exponential signal embedded in white Gaussian noise. The response of the estimators to various signal conditions. including low signal-to-noise ratios, high Doppler frequency excursions and high modulation frequencies, is investigated. Using the results. consideration is given to the suitability of each technique for estimating the magnitude, phase and power spectrum of the Doppler velocity time series. These are fundamental quantities required for studying sea surface scattering mechanisms and remotely sensing oceanographic properties. C1 Northeastern Univ, Dept Elect & Comp Engn, Boston, MA 02115 USA. RP Allan, N (reprint author), USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. NR 20 TC 5 Z9 7 U1 1 U2 2 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1350-2395 J9 IEE P-RADAR SON NAV JI IEE Proc.-Radar Sonar Navig. PD DEC PY 1998 VL 145 IS 6 BP 367 EP 373 DI 10.1049/ip-rsn:19982426 PG 7 WC Telecommunications SC Telecommunications GA 167JF UT WOS:000078628200009 ER PT J AU Kub, FJ AF Kub, FJ TI Introduction to the sensor section SO IEEE JOURNAL OF SOLID-STATE CIRCUITS LA English DT Editorial Material C1 USN, Res Lab, Washington, DC 20375 USA. RP Kub, FJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9200 J9 IEEE J SOLID-ST CIRC JI IEEE J. Solid-State Circuit PD DEC PY 1998 VL 33 IS 12 BP 2080 EP 2080 DI 10.1109/JSSC.1998.735550 PG 1 WC Engineering, Electrical & Electronic SC Engineering GA 144DH UT WOS:000077298100026 ER PT J AU Lucke, RL AF Lucke, RL TI Tilting aplanat RF telescope SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Letter DE beam steering; mirror; radio astronomy AB Beam steering by tilting the secondary is common in two-mirror RF telescopes, but it is not generally recognized that optical quality need not suffer as the beam is steered: a tilting aplanat can maintain diffraction-limited performance over fields of a few degrees. C1 USN, Res Lab, Code 7227, Washington, DC 20375 USA. RP Lucke, RL (reprint author), USN, Res Lab, Code 7227, Washington, DC 20375 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD DEC PY 1998 VL 46 IS 12 BP 1886 EP 1887 DI 10.1109/8.743840 PG 2 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 164UP UT WOS:000078482200017 ER PT J AU Owsley, NL Hull, AJ AF Owsley, NL Hull, AJ TI Beamformed nearfield imaging of a simulated coronary artery containing a stenosis SO IEEE TRANSACTIONS ON MEDICAL IMAGING LA English DT Article DE coronary artery disease; nearfield beamforming; noninvasive detection; phased-array technology ID MODERATE REYNOLDS-NUMBERS; VELOCITY-MEASUREMENTS; FLOW; TUBE; OCCLUSIONS; DOWNSTREAM AB This paper is concerned with the potential for the detection and location of an artery containing a partial blockage by exploiting the space-time properties of the shear wave field in the surrounding elastic soft tissue. As a demonstration of feasibility, an array of piezoelectric film vibration sensors is placed on the free surface of a urethane mold that contains a surgical tube. Inside the surgical tube is a nylon constriction that inhibits the water flowing through the tube. A turbulent field develops in and downstream from the blockage, creating a randomly fluctuating pressure on the inner wall of the tube. This force produces shear and compressional wave energy in the urethane. After the array is used to sample the dominant shear wave space-time energy field at low frequencies, a nearfield (i.e., focused) beamforming process then images the energy distribution in the three-dimensional solid. Experiments and numerical simulations are included to demonstrate the potential of this noninvasive procedure for the early identification of vascular blockages-the typical precursor of serious arterial disease in the human heart. C1 USN, Undersea Warfare Ctr Div, Submarine Sonar Dept, Adv Sonar Technol Branch, Newport, RI 02841 USA. USN, Undersea Warfare Ctr Div, Submarine Sonar Dept, Towed Array Exploratory Dev Branch, Newport, RI 02841 USA. RP Owsley, NL (reprint author), USN, Undersea Warfare Ctr Div, Submarine Sonar Dept, Adv Sonar Technol Branch, Newport, RI 02841 USA. EM owsley_norm_1@c20msm.npt.nuwc.navy.mil NR 23 TC 9 Z9 9 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0278-0062 J9 IEEE T MED IMAGING JI IEEE Trans. Med. Imaging PD DEC PY 1998 VL 17 IS 6 BP 900 EP 909 DI 10.1109/42.746623 PG 10 WC Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Computer Science; Engineering; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA 166TH UT WOS:000078592900005 PM 10048847 ER PT J AU Roman, JE Nichols, LT Williams, KJ Esman, RD Tavik, GC Livingston, M Parent, MG AF Roman, JE Nichols, LT Williams, KJ Esman, RD Tavik, GC Livingston, M Parent, MG TI Fiber-optic remoting of an ultrahigh dynamic range radar SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article; Proceedings Paper CT 1998 International Microwave Symposium / Radio Frequency Integrated Circuits Symposium / Automatic-RF-Techniques-Group Meeting CY 1998 CL BALTIMORE, MARYLAND SP Automat RF Tech Grp DE active array antennas; fiber-optic remoting; optical fiber delay lines; transmitter/receiver modules AB We demonstrate, for the first time, fiber-optic remoting of an X-band radar with ultrahigh dynamic range, and show that photonic components can meet the stringent phase noise requirements for remoting modern radars. Fiber optic links were designed and built to remote the antenna and transmitter of the AN/SPQ-9B Advanced Development Model radar. The remoting links tested successfully in both transmit and receive configurations without significantly degrading the measured, postintegration, 87-dB signal-to-noise ratio of the radar. The results show the potential of photonic technology to remote the transmitter/receiver modules of active array radars. C1 USN, Res Lab, Washington, DC 20375 USA. RP Roman, JE (reprint author), USN, Res Lab, Code 5672, Washington, DC 20375 USA. NR 4 TC 35 Z9 38 U1 3 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD DEC PY 1998 VL 46 IS 12 BP 2317 EP 2323 DI 10.1109/22.739217 PN 2 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 158CT UT WOS:000078099000021 ER PT J AU David, G Yun, TY Crites, MH Whitaker, JF Weatherford, TR Jobe, K Meyer, S Bustamante, MJ Goyette, B Thomas, S Elliott, KR AF David, G Yun, TY Crites, MH Whitaker, JF Weatherford, TR Jobe, K Meyer, S Bustamante, MJ Goyette, B Thomas, S Elliott, KR TI Absolute potential measurements inside microwave digital IC's using a micromachined photoconductive sampling probe SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article; Proceedings Paper CT 1998 International Microwave Symposium / Radio Frequency Integrated Circuits Symposium / Automatic-RF-Techniques-Group Meeting CY 1998 CL BALTIMORE, MARYLAND SP Automat RF Tech Grp DE integrated-circuit testing; microwave measurements; nondestructive testing; photoconductive measurements; time-domain measurements; voltage measurement ID PICOSECOND OPTOELECTRONIC MEASUREMENT; CIRCUITS; PROPAGATION; SENSITIVITY; PARAMETERS AB A measurement system for internal node testing of integrated circuits using a micromachined photoconductive sampling probe is described and characterized, Special emphasis is placed upon the system performance, demonstrating how absolute voltage measurements are achieved in a dc-to-mm-wave bandwidth, The feasibility of the setup is illustrated using an InP heterojunction bipolar transistor frequency divider. Detailed waveforms at different circuit nodes and the corresponding propagation delays from within this circuit at operating frequencies up to 10 GHz are presented. The results demonstrate for the first time the use of photoconductive probes for calibration-free, absolute-voltage, de-coupled potential measurements in high-frequency and high-speed integrated circuits. C1 Univ Michigan, Ctr Ultrafast Opt Sci, Ann Arbor, MI 48109 USA. Univ Michigan, Dept Elect Engn & Comp Sci, Ann Arbor, MI 48109 USA. USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. Hughes Space & Commun Co, Hughes Elect Corp, El Segundo, CA 90009 USA. LLC, HRL Labs, Malibu, CA 90765 USA. RP David, G (reprint author), Univ Michigan, Ctr Ultrafast Opt Sci, Ann Arbor, MI 48109 USA. NR 21 TC 9 Z9 9 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD DEC PY 1998 VL 46 IS 12 BP 2330 EP 2337 DI 10.1109/22.739220 PN 2 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA 158CT UT WOS:000078099000023 ER PT J AU Niu, GF Banerjee, G Cressler, JD Roldan, JM Clark, SD Ahlgren, DC AF Niu, GF Banerjee, G Cressler, JD Roldan, JM Clark, SD Ahlgren, DC TI Electrical probing of surface and bulk traps in proton-irradiated gate-assisted lateral PNP transistors SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CA SP IEEE/NPSS Radiat Effects Comm AB The effects of 46 MeV proton irradiation-induced trap generation and its impact on the electrical characteristics of gate assisted lateral PNP transistors (GLPNP) are investigated for the first rime. At proton fluence as high as 10(12) p/cm(2) the devices show a negligible current gain degradation, and at 10(13) p/cm(2) the devices are still functional. The excellent radiation hardness is attributed to the much thinner gate oxide than in conventional lateral PNPs and its gate assisted operation. By changing the gate bias, and modulating the surface status from accumulation to inversion, the surface traps can be electrically probed from the I-V characteristics. A base current peak is observed after radiation, and is understood using 2D device simulation to be a result of the increase in oxide charge and surface trap density, in conjunction with the different SRH recombination rate limiting mechanism in presence of high density traps. The inverse mode operation is shown to be a useful tool for probing the bulk traps. C1 Auburn Univ, Alabama Microelect Sci & Technol Ctr, Dept Elect Engn, Auburn, AL 36849 USA. USN, Ctr Surface Warfare, Crane, IN 47522 USA. IBM Corp, IBM Microelect, Hopewell Jct, NY 12533 USA. RP Niu, GF (reprint author), Auburn Univ, Alabama Microelect Sci & Technol Ctr, Dept Elect Engn, 200 Broun Hall, Auburn, AL 36849 USA. NR 5 TC 18 Z9 19 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2361 EP 2365 DI 10.1109/23.736455 PN 1 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200007 ER PT J AU Stahlbush, RE Lawrence, RK Hughes, HL AF Stahlbush, RE Lawrence, RK Hughes, HL TI H+ motion in SiO2: Incompatible results from hydrogen-annealing and radiation models SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID INTERFACE TRAP FORMATION; BURIED OXIDE LAYER; SIMOX STRUCTURES; TIME-DEPENDENCE; THIN-FILMS; CHARGE; TRANSISTORS; GENERATION; REDUCTION; MECHANISM AB Two models that incorporate the same mobile H+ entity are the radiation model by McLean [1] and the mobile charge model of hydrogen-annealed oxide by Vanheusden et al. [2]. Mobile charge in hydrogen-annealed silicon-on-insulator (SOI) buried oxides before and after irradiation was studied to investigate discrepancies between the two models. We examined Unibond, low-dose SIMOX, and single- and triple implant standard-dose SIMOX as well as single- and triple-implant SIMOX with supplemental oxygen implantation. To measure H+ motion as fast as 0.01 sec we developed a gate pulse method and combined it with standard I-V techniques to measure the full range of H+ response times. All but single-implant SIMOX exhibit mobile H+ that can be cycled between the Si/SiO2 interfaces without reacting or being trapped. Trapping near the top interface attenuates the cycling of H+ in single-implant SIMOX. The transit H+ times were strongly affected by defects in the oxides and varied by an order of magnitude in oxides with the same thickness. The transit time varied linearly with oxide thickness. The effects of irradiation on the mobile H+ was studied to see if the irradiation would introduce defects that modify the H+ behavior and that bring the two models into agreement. No convergence was observed. After irradiation, H+ could be cycled between the Si/SiO2 interfaces without reacting and its transit time across the oxide was not altered. C1 USN, Res Lab, Washington, DC 20375 USA. ARACOR, Oxon Hill, MD 20745 USA. RP Stahlbush, RE (reprint author), USN, Res Lab, Code 6816, Washington, DC 20375 USA. NR 31 TC 33 Z9 33 U1 3 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2398 EP 2407 DI 10.1109/23.736460 PN 1 PG 10 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200012 ER PT J AU Roldan, JM Niu, GF Ansley, WE Cressler, JD Clark, SD Ahlgren, DC AF Roldan, JM Niu, GF Ansley, WE Cressler, JD Clark, SD Ahlgren, DC TI An investigation of the spatial location of proton-induced traps in SiGe HBTs SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID IONIZING-RADIATION; INDUCED DEGRADATION AB The effects of 46 MeV proton irradiation induced trap generation and its impact on the electrical characteristics of silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) from an advanced ultrahigh vacuum/chemical vapor deposition (UHV/CVD) SiGe BiCMOS technology are examined and discussed for the first time. At proton fluences as high as 10(14) p/cm(2) the peak current gain of the devices degraded by less than 8% compared to the pre-irradiated samples. The maximum oscillation frequency and cutoff frequency of the SiGe HBTs showed only minor degradation after 10(14) p/cm(2). Calibration of 2-D device simulation (MEDICI) to measured data in both forward and inverse modes of operation was used to infer the spatial location of the proton-induced traps. Traps in the collector-base space charge region appear as generation/recombination (G/R) centers in the inverse emitter-base region and are the result of displacement damage. Traps at the emitter-base spacer oxide interface appear as G/R centers in the forward emitter-base space charge region and are the result of ionization damage. Taken together, these results suggest that UHV/CVD SiGe HBT technology is robust to proton fluences at least as high as 10(13) p/cm(2) without radiation hardening. C1 Auburn Univ, Alabama Microelect Sci & Technol Ctr, Dept Elect Engn, Auburn, AL 36849 USA. USN, Ctr Surface Warfare, Crane, IN 47522 USA. IBM Corp, Hopewell Junction, NY 12533 USA. RP Roldan, JM (reprint author), Auburn Univ, Alabama Microelect Sci & Technol Ctr, Dept Elect Engn, 200 Broun Hall, Auburn, AL 36849 USA. NR 14 TC 32 Z9 35 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2424 EP 2429 DI 10.1109/23.736481 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200015 ER PT J AU Liu, ST Jenkins, WC Hughes, HL AF Liu, ST Jenkins, WC Hughes, HL TI Total dose radiation hard 0.35 mu m SOI CMOS technology SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm AB This paper presents the total dose radiation performance of 0.35 mu m SOI CMOS devices fabricated in a radiation hard full dose SIMOX technology. The radiation performance is characterized by transistor threshold voltage shifts, transistor array leakage currents, and 256K SRAM standby currents as a function of total dose up to 10 Mrad(SiO2). The worst case threshold voltage shifts of front channels are less than 60 mV for PMOS transistors at 1 Mrad(SiO2) and less than 10 mV for NMOS transistors. No significant radiation induced leakage currents are observed in small transistor arrays to 10 Mrad(SiO2). Standby currents of 256K SRAMs are less than the 1.5 mA specification over the total dose range of 1 Mrad(SiO2). The results suggest high density SRAMs and ASIC fabricated in this technology will perform well in harsh radiation environment. C1 Honeywell Inc, Solid State Elect Ctr, Plymouth, MN 55441 USA. USN, Res Lab, Washington, DC 20375 USA. RP Liu, ST (reprint author), Honeywell Inc, Solid State Elect Ctr, Plymouth, MN 55441 USA. NR 16 TC 44 Z9 59 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2442 EP 2449 DI 10.1109/23.736484 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200018 ER PT J AU Mrstik, BJ McMarr, PJ Lawrence, RK Hughes, HL AF Mrstik, BJ McMarr, PJ Lawrence, RK Hughes, HL TI A study of the radiation sensitivity of non-crystalline SiO2 films using spectroscopic ellipsometry SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID ELECTRON-SPIN-RESONANCE; BURIED OXIDE; 100 SILICON; SIO2-FILMS; RELAXATION; INTERFACE; DEGRADATION; TECHNOLOGY; DENSITY; MODEL AB Dry thermal oxides were grown on Si substrates at temperatures from 900 degrees C to 1200 degrees C. Portions of these oxides were then annealed for 10 min at temperatures from 900 degrees C to 1125 degrees C. Spectroscopic ellipsometry was used to determine the density of these oxides, and to look for the existence of an interfacial layer. It was found that the oxide density depends on both the growth temperature and the anneal temperature. No evidence was found of an interfacial layer. The oxides were then irradiated with x-rays, and the radiation-induced shift of the flatband voltage was determined. It was found that the radiation response was related to the oxide density determined by spectroscopic ellipsometry. These results suggest that the macroscopic structure of the oxide influences the extent of charge trapping. C1 USN, Res Lab, Washington, DC 20375 USA. ARACOR, SFA, Washington, DC 20375 USA. RP Mrstik, BJ (reprint author), USN, Res Lab, Code 6816, Washington, DC 20375 USA. NR 31 TC 6 Z9 6 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2450 EP 2457 DI 10.1109/23.736485 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200019 ER PT J AU Titus, JL Wheatley, CF Van Tyne, KM Krieg, JF Burton, DI Campbell, AB AF Titus, JL Wheatley, CF Van Tyne, KM Krieg, JF Burton, DI Campbell, AB TI Effect of ion energy upon dielectric breakdown of the capacitor response in vertical power MOSFETs SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID EVENT GATE-RUPTURE; INDUCED ELECTRICAL BREAKDOWN; SILICON CAPACITORS; OXIDE THICKNESS; SEGR FAILURE; EXPRESSION AB The effect of ion energy upon the ion-induced dielectric breakdown response of the capacitor response in vertical power metal-oxide semiconductor field effect transistors (MOSFETs) was investigated. The single event gate rupture response was experimentally determined using mono-energetic ion beams of copper, niobium, and gold. Irradiations were conducted using an ion species tuned to different energies, producing a range of linear energy transfer (LET) values for that ion. Numerous MOSFETs were characterized to identify the onset of ion-induced dielectric breakdown. These data along with previously taken data demonstrated that the ion-induced dielectric breakdown cannot be adequately described in terms of LET, but is better described in terms of atomic number (Z). Based upon these observations, a new semi-empirical expression is presented describing the critical ion-induced breakdown response in terms of Z instead of LET. This expression is shown to be a better single event gate rupture model of the capacitor response. C1 USN, Ctr Surface Warfare, Crane, IN 47522 USA. USN, Res Lab, Moutaintop, PA 18707 USA. RP Titus, JL (reprint author), USN, Ctr Surface Warfare, 300 Hwy 361, Crane, IN 47522 USA. NR 21 TC 43 Z9 43 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2492 EP 2499 DI 10.1109/23.736490 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200024 ER PT J AU Musseau, O Ferlet-Cavrois, V Campbell, AB Knudson, AR Buchner, S Fischer, B Schlogl, M AF Musseau, O Ferlet-Cavrois, V Campbell, AB Knudson, AR Buchner, S Fischer, B Schlogl, M TI Technique to measure an ion track profile SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID CHARGE COLLECTION; SILICON; ENERGY; UPSETS AB Effects of the radial density distribution of carriers generated in a single ion track have been observed in thin silicon detectors. These devices have been irradiated with either an ion microbeam at low energy or a high-energy standard ion beam. We describe the mode of operation of the tested structure, and propose an interpretation of the experimental charge collection data to extract information on the ion track profile. Experimental results are compared to 3D simulations and simplified analytical profiles. C1 CEA, Bruyeres Le Chatel, France. USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Landover, MD 20785 USA. GSI Darmstadt, D-6100 Darmstadt, Germany. RP Musseau, O (reprint author), CEA, Bruyeres Le Chatel, France. NR 26 TC 11 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2563 EP 2570 DI 10.1109/23.736498 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200032 ER PT J AU Freitag, RK Brown, DB AF Freitag, RK Brown, DB TI Study of low-dose-rate radiation effects on commercial linear bipolar ICs SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID HARDNESS-ASSURANCE; JUNCTION TRANSISTORS; GAIN DEGRADATION; DEVICES; ISSUES AB The results of a detailed study of the degradation of commercial linear bipolar ICs due to irradiation at four dose rates are presented. The time dependence of the degradation rate at the different dose rates is shown to be consistent with a model that describes a mechanism for defect generation in the devices used in this study. Based on this model, an accelerated test procedure for bipolar devices is proposed. C1 USN, Res Lab, Washington, DC 20375 USA. RP Freitag, RK (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 17 TC 63 Z9 66 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2649 EP 2658 DI 10.1109/23.736510 PN 1 PG 10 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200044 ER PT J AU Pease, RL Gehlhausen, M Krieg, J Titus, J Turflinger, T Emily, D Cohn, L AF Pease, RL Gehlhausen, M Krieg, J Titus, J Turflinger, T Emily, D Cohn, L TI Evaluation of proposed hardness assurance method for bipolar linear circuits with enhanced low dose rate sensitivity (ELDRS) SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID INTEGRATED-CIRCUITS; MICROCIRCUITS AB Data are presented on several low dose rate sensitive bipolar linear circuits to evaluate a proposed hardness assurance method. The circuits include primarily operational amplifiers and voltage comparators with a variety of sensitive components and failure modes. The proposed method, presented in 1997, includes an option between a law dose rate test at 10 mrd(Si)/s and room temperature and a 100 degrees C elevated temperature irradiation test at a moderate dose rate. The results of this evaluation demonstrate that a 10 mrd(Si)/s test is able (in all but one case) to bound the worst case response within a factor of 2. For the moderate dose rate, 100 degrees C test the worst case response is within a factor of 3 for 8 of 11 circuits, and for some circuits overpredicts the low dose rate response. The irradiation bias used for these tests often represents a more degrading bias condition than would be; encountered in a typical space system application. C1 RLP Res, Albuquerque, NM 87122 USA. USN, Ctr Surface Warfare, Crane, IN 47522 USA. Def Special Weap Agcy, Alexandria, VA 20122 USA. RP Pease, RL (reprint author), RLP Res, 1718 Quail Run Court NE, Albuquerque, NM 87122 USA. NR 12 TC 40 Z9 43 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2665 EP 2672 DI 10.1109/23.736512 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200046 ER PT J AU Titus, JL Combs, WE Turflinger, TL Krieg, JF Tausch, HJ Brown, DB Pease, RL Campbell, AB AF Titus, JL Combs, WE Turflinger, TL Krieg, JF Tausch, HJ Brown, DB Pease, RL Campbell, AB TI First observations of enhanced low dose rate sensitivity (ELDRS) in space: One part of the MPTB experiment SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID INTEGRATED-CIRCUITS; GAIN DEGRADATION; TRANSISTORS; SUBSTRATE AB Bipolar devices, most notably circuits fabricated with lateral PNP transistors (LPNP) and substrate PNP transistors (SPNP), have been observed to exhibit an enhanced low dose rate sensitivity when exposed to ionizing radiation. These dose rate sensitive bipolar devices exhibited enhanced degradation of base current in transistors and of input bias current, offset current, and/or offset voltage in linear circuits at dose rates less than 0.1 rd(Si)/s) compared to devices irradiated at dose rates greater than 1 rd(Si)/s). The total dose responses of several bipolar transistors and linear circuits in a space environment are demonstrated to exhibit enhanced degradation comparable, in magnitude, to ground-based data irradiated at a dose rate of 10 mrd(Si)/s indicating that enhanced low dose rate sensitivities (ELDRS) do indeed exist in space. C1 USN, Ctr Surface Warfare, Crane, IN 47522 USA. Mission Res Corp, Albuquerque, NM 87106 USA. USN, Res Lab, Washington, DC 20375 USA. RLP Res, Albuquerque, NM 87122 USA. RP Titus, JL (reprint author), USN, Ctr Surface Warfare, 300 Hwy 361, Crane, IN 47522 USA. NR 13 TC 10 Z9 15 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2673 EP 2680 DI 10.1109/23.736514 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200047 ER PT J AU Shinn, JL Cucinotta, FA Simonsen, LC Wilson, JW Badavi, FF Badhwar, GD Miller, J Zeitlin, C Heilbronn, T Tripathi, RK Clowdsley, MS Heinbockel, JH Xapsos, MA AF Shinn, JL Cucinotta, FA Simonsen, LC Wilson, JW Badavi, FF Badhwar, GD Miller, J Zeitlin, C Heilbronn, T Tripathi, RK Clowdsley, MS Heinbockel, JH Xapsos, MA TI Validation of a comprehensive space radiation transport code SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID ACCURATE UNIVERSAL PARAMETERIZATION; GALACTIC COSMIC-RADIATION; ABSORPTION CROSS-SECTIONS; HEAVY-ION FRAGMENTATION; TARGET FRAGMENTATION; ENERGY DEPOSITION; MODEL; SPECTRA; SHUTTLE; COLLISIONS AB The HZETRN code has been developed over the past decade to evaluate the local radiation fields within sensitive materials on spacecraft in the space environment. Most of the more important nuclear and atomic processes are now modeled and evaluation within a complex spacecraft geometry with differing material components, including transition effects across boundaries of dissimilar materials, are included. The atomic/nuclear database and transport procedures have received limited validation in laboratory testing with high energy ion beams.,The codes have been applied in design of the SAGE-III instrument resulting in material changes to control injurious neutron production, in the study of the Space Shuttle single event upsets, and in validation with space measurements (particle telescopes, tissue equivalent. proportional counters, CR-39) on Shuttle and Mir. The present paper reviews the code development and presents recent results in laboratory and space flight validation. C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Christopher Newport Univ, Newport News, VA 23606 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA USA. Hampton Univ, Hampton, VA 23668 USA. Old Dominion Univ, Norfolk, VA USA. USN, Res Lab, Washington, DC 20375 USA. RP Shinn, JL (reprint author), NASA, Langley Res Ctr, Hampton, VA 23665 USA. NR 48 TC 17 Z9 18 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2711 EP 2719 DI 10.1109/23.736519 PN 1 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200052 PM 11542474 ER PT J AU Reed, RA Marshall, PW Johnston, AH Barth, JL Marshall, CJ LaBel, KA D'Ordine, M Kim, HS Carts, MA AF Reed, RA Marshall, PW Johnston, AH Barth, JL Marshall, CJ LaBel, KA D'Ordine, M Kim, HS Carts, MA TI Emerging optocoupler issues with energetic particle-induced transients and permanent radiation degradation SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID DISPLACEMENT DAMAGE AB Radiation-induced permanent degradation and single event transient effects for optocouplers are discussed in this paper. These two effects are independent to the first order and will be addressed separately. Displacement damage-induced degradation of optocoupler current transfer ratio is reviewed. New data are presented that show the importance of application specific testing and that generalized quantification of optocoupler CTR degradation can lead to incorrect predictions of actual circuit performance in a radiation environment. Data are given for various circuit loading and drive current parameters. Previous work that introduces the idea that two mechanisms exist for inducing transients on the optocoupler output is discussed. New data are presented that extends the evidence of this dual mechanism hypothesis. In this work measurements show that single event transient cross sections and transient propagation varies with circuit filtering. Finally, we discuss utilization of the optocouplers in the space environment. New data are applied to two examples: one on permanent degradation and the other on single event transient rates in high bandwidth applications. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SFA Inc, NRL, Landover, MD 20785 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NRL, Washington, DC 20375 USA. Ball Aerosp Syst Grp, Boulder, CO 80301 USA. Jackson & Tull Chartered Engineers, Washington, DC USA. RP Reed, RA (reprint author), NASA, Goddard Space Flight Ctr, Code 562, Greenbelt, MD 20771 USA. NR 14 TC 33 Z9 35 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2833 EP 2841 DI 10.1109/23.736536 PN 1 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200069 ER PT J AU Marshall, CJ Marshall, PW Carts, MA Reed, RA LaBel, KA AF Marshall, CJ Marshall, PW Carts, MA Reed, RA LaBel, KA TI Proton-induced transient effects in a metal-semiconductor-metal (MSM) photodetector for optical-based data transfer SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID SATELLITE DATA MANAGEMENT; DATA LINKS; GAAS; INGAAS AB We present a study of proton transient effects in metal-semiconductor-metal (MSM) photodetectors, which demonstrates their inherent advantage for minimizing Single Event Effects (SEEs) in proton environments. Upset mechanisms are characterized for 830 nm GaAs and 1300 nm InGaAs detectors. Only protons incident at grazing angles are likely to cause a bit errors by direct ionization. The MSM technology appears to be a more robust to single bit errors than thicker 1300 nm p-i-n diode structures which we have previously shown to be susceptible to errors from direct ionization events at all angles, and also at relatively high optical powers [1]. For a given receiver, the relative contributions of direct ionization and nuclear reaction upset mechanisms at a specific data rate and optical power are determined by the geometry of the charge collection volume of the detector. We show that state-of-the-art p-i-n detectors can also display a reduced sensitivity to direct ionization by incident protons except at grazing angles. C1 NRL, Washington, DC 20375 USA. SFA Inc, Largo, MD 20785 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Marshall, CJ (reprint author), NRL, Code 6611,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 24 TC 13 Z9 13 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2842 EP 2848 DI 10.1109/23.736537 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200070 ER PT J AU Messenger, SR Walters, RJ Xapsos, MA Summers, GP Burke, EA AF Messenger, SR Walters, RJ Xapsos, MA Summers, GP Burke, EA TI Carrier removal in p-type InP SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID DISPLACEMENT DAMAGE; SOLAR-CELLS; HIGH-ENERGY; RADIATION; IRRADIATION; PROTON; SEMICONDUCTORS AB Electron and proton carrier removal rates due to 1 MeV electrons, 3 and 10 MeV protons, and 2 MeV alpha particles in p-type InP are found to be linearly proportional to nonionizing energy loss and independent of the initial carrier concentration over the range from 10(16) to 4 x 10(17) cm(-3). C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Largo, MD 20774 USA. Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD USA. RP Messenger, SR (reprint author), SFA Inc, Largo, MD 20774 USA. NR 16 TC 10 Z9 10 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2857 EP 2860 DI 10.1109/23.736539 PN 1 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200072 ER PT J AU Titus, JL Wheatley, CF AF Titus, JL Wheatley, CF TI Proton-induced dielectric breakdown of power MOSFETs SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID EVENT-GATE-RUPTURE; OXIDE THICKNESS; SEGR FAILURE; EXPRESSION; BURNOUT; ENERGY AB Proton-induced dielectric breakdown of vertical power metal oxide semiconductor field effect transistors (MOSFETs) is reported for the first time and compared to the heavy-ion-induced gate rupture response. Power MOSFETs from five variants were fabricated with nominal gate oxide thicknesses of 30, 50, 70, 100, and 150 nm. Devices from each variant were characterized to several heavy ion beams as previously reported. and then other devices from each variant were subsequently characterized to 200-MeV protons, as reported here. In addition, a limited characterization was performed using 44-MeV protons. Employing a similar test methodology, failure thresholds for the onset of proton-induced dielectric breakdown were determined for each gate oxide variant. The measured proton-induced dielectric breakdown thresholds induced by 200- and 44-MeV protons are compared to the measured heavy-ion induced failure thresholds. C1 USN, Ctr Surface Warfare, Crane, IN 47522 USA. RP Titus, JL (reprint author), USN, Ctr Surface Warfare, 300 Hwy 361, Crane, IN 47522 USA. NR 17 TC 14 Z9 14 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2891 EP 2897 DI 10.1109/23.736544 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200077 ER PT J AU LaBel, KA Marshall, PW Barth, JL Katz, RB Reed, RA Leidecker, HW Kim, HS Marshall, CJ AF LaBel, KA Marshall, PW Barth, JL Katz, RB Reed, RA Leidecker, HW Kim, HS Marshall, CJ TI Anatomy an in-flight anomaly: Investigation of proton-induced SEE test results for stacked IBM DRAMs SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID RADIATION AB We present ground test and space flight data describing a single event anomaly that affects multiple bytes in a stacked DRAM module. A 12 Gbit solid state recorder containing 1,440 DRAM die experiences the anomalous events at a rate requiring testing of a large sample set of these modules. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Jackson & Tull Chartered Engineers, Lanham, MD 20706 USA. NRL, Washington, DC 20375 USA. RP LaBel, KA (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 11 TC 25 Z9 25 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2898 EP 2903 DI 10.1109/23.736545 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200078 ER PT J AU Xapsos, MA Summers, GP Burke, EA AF Xapsos, MA Summers, GP Burke, EA TI Probability model for peak fluxes of solar proton events SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID FLUENCE MODEL; SPACE AB A predictive model of worst case, > 10 MeV solar proton event peak fluxes is presented that fully accounts for the length of the space mission and the corresponding risk. Furthermore, the model predicts there is an upper limit which the peak flux can attain that is approximately twice the size of the largest observed peak flux to date. This is more restrictive than previous estimates of upper limits of solar proton event sizes that are based on historical evidence. It leads to a well-defined guideline for designing a space system that is radiation-hard against failures due to solar proton event peak flux effects. The model is based on a description of the solar proton event peak flux distribution obtained through application of the maximum entropy principle. This principle provides a mathematical basis for selecting the least biased distribution compatible with known information, and is especially useful for sets of data that are incomplete. The principle leads to a probability distribution that is a "truncated" power law. It behaves as a power law with an index of about -0.4 for 5-minute averaged peak fluxes less than about 10(3) cm(-2) s(-1) sr(-1). The distribution decreases more rapidly than this for larger peak flux values, and goes to zero at a maximum value of 1.78 x 10(5) cm(-2) s(-1) sr(-1). The theoretical distribution is in good agreement with satellite data dating back to 1967, which spans about 4 orders of magnitude in peak fluxes. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. RP Xapsos, MA (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 27 TC 31 Z9 31 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2948 EP 2953 DI 10.1109/23.736551 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200084 ER PT J AU Lampe, M Joyce, G Manheimer, WM Slinker, SP AF Lampe, M Joyce, G Manheimer, WM Slinker, SP TI Quasi-neutral particle simulation of magnetized plasma discharges: General formalism and application to ECR discharges SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE electron cyclotron resonance plasma; particle-in-cell simulation; particle simulation; plasma simulation; quasineutral plasma ID FIELD-EQUATIONS; CROSS-SECTIONS; KINETIC-THEORY; RF DISCHARGE; DENSITY; ARGON; MODEL; COLLISIONS; TRANSITION; NITROGEN AB We have developed an electrostatic particle-in-cell/Monte Carlo (PIC/MC) simulation method for magnetized discharges, in which both internal electric fields and sheath potentials are determined from the requirement of quasineutrality within the bulk plasma, rather than by solving Poisson's equation. Thus the electric field is not sensitive to statistical noise which may occur in the small quantity n(e) - n(i). Sheaths are treated self consistently as thin potential barriers, and the Bohm criterion for ion flux into the sheath is imposed as a boundary condition. Electron plasma oscillations do not appear in the model, and the debye length is essentially set to zero, Thus time steps and spatial gridding can be chosen to represent the characteristic macroscopic time and space scales of interest, which may be orders of magnitude larger than the plasma frequency/debye length scales, The simulation technique correctly represents kinetic features such as non-Maxwellian distributions and Landau damping and can be used for either collisional or collisionless plasmas. We present results from an axisymmetric simulation of an electron cyclotron resonance (ECR) discharge in low-pressure argon, which show that the discharge is strongly affected by cross-field ion hows, even when the vessel walls are insulators, We also present analytic calculations based on the model, which afford new insights into cross-field transport in a metallic vessel and show that the classic Simon diffusion can be strongly inhibited by the effect of sheath potentials. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Lampe, M (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. EM lampe@ppd.nrl.navy.mil; joyce@ppd.nrl.navy.mil; manheime@ccs.nrl.navy.mil; slinker@ppd.nrl.navy.mil NR 60 TC 24 Z9 29 U1 2 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD DEC PY 1998 VL 26 IS 6 BP 1592 EP 1609 DI 10.1109/27.747877 PG 18 WC Physics, Fluids & Plasmas SC Physics GA 162DF UT WOS:000078329600002 ER PT J AU Gaver, DP Jacobs, PA AF Gaver, DP Jacobs, PA TI Methodology for an operationally-based test length decision SO IIE TRANSACTIONS LA English DT Article AB Weapon systems that function destructively (e.g., missile or torpedo) are to be acquired in a lot of size m. Acceptance of the lot is based on the result of an operational test, administered to part of the lot: if the test results indicate positive operational value the lot is accepted and the remaining part of the lot is fielded; otherwise the lot is "rejected". A test plan is designed that establishes an optimal number of weapon copies to test, given models of the operational gain of the fielded weapon under two tactical options, and the uncertainty in the weapon's predicted probability of success after the test is complete. The major test objective is to realize possible operational utility from the lot of items, and secondarily to demonstrate arbitrary levels of certainty. C1 USN, Postgrad Sch, Dept Operat Res, Monterey, CA 93943 USA. RP Gaver, DP (reprint author), USN, Postgrad Sch, Dept Operat Res, Monterey, CA 93943 USA. NR 2 TC 0 Z9 0 U1 1 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0740-817X J9 IIE TRANS JI IIE Trans. PD DEC PY 1998 VL 30 IS 12 BP 1129 EP 1134 PG 6 WC Engineering, Industrial; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA 202FF UT WOS:000080640900004 ER PT J AU Abdelguerfi, M Wynne, C Cooper, E Roy, L Shaw, K AF Abdelguerfi, M Wynne, C Cooper, E Roy, L Shaw, K TI Representation of 3-D elevation in terrain databases using hierarchical triangulated irregular networks: a comparative analysis SO INTERNATIONAL JOURNAL OF GEOGRAPHICAL INFORMATION SCIENCE LA English DT Article AB 3-D terrain representation plays an important role in a number of terrain database applications. Hierarchical Triangulated Irregular Networks (TINs) provide a variable-resolution terrain representation that is based on a nested triangulation of the terrain. This paper compares and analyzes existing hierarchical triangulation techniques. The comparative analysis takes into account how aesthetically appealing and accurate the resulting terrain representation is. Parameters, such as adjacency, slivers, and streaks, are used to provide a measure on how aesthetically appealing the terrain representation is. Slivers occur when the triangulation produces thin and slivery triangles. Streaks appear when there are too many triangulations done at a given vertex. Simple mathematical expressions are derived for these parameters, thereby providing a fairer and a more easily duplicated comparison. In addition to meeting the adjacency requirement, an aesthetically pleasant hierarchical TINs generation algorithm is expected to reduce both slivers and streaks while maintaining accuracy. A comparative analysis of a number of existing approaches shows that a variant of a method originally proposed by Scarlatos exhibits better overall performance. C1 Univ New Orleans, Dept Comp Sci, New Orleans, LA 70148 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Abdelguerfi, M (reprint author), Univ New Orleans, Dept Comp Sci, New Orleans, LA 70148 USA. EM mahdi@cs.uno.edu; cwynne@cs.uno.edu; eccooper@cs.uno.edu; rladner@cs.uno.edu; shaw@nrlssc.navy.mil NR 15 TC 6 Z9 7 U1 1 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 1365-8816 J9 INT J GEOGR INF SCI JI Int. J. Geogr. Inf. Sci. PD DEC PY 1998 VL 12 IS 8 BP 853 EP 873 PG 21 WC Computer Science, Information Systems; Geography; Geography, Physical; Information Science & Library Science SC Computer Science; Geography; Physical Geography; Information Science & Library Science GA 140JX UT WOS:000077085100005 ER PT J AU Buchanan, JL Gilbert, RP AF Buchanan, JL Gilbert, RP TI Transmission loss in a shallow ocean over a two-layer seabed SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article ID BIOT SEDIMENT MODEL; ACOUSTIC PROPAGATION; FAR-FIELD; BOTTOM AB Three mathematical models of a two-layer seabed are considered. The first assumes that both layers are elastic solids, the second that the upper layer is poroelastic while the substrate is elastic, and the third that both layers are poroelastic. The first and third models are found to produce reasonable agreement with data and each other, but the second model produces poor predictions because of mathematical incompatibilities of the poroelastic and elastic models. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN Acad, Dept Math, Annapolis, MD 21402 USA. Univ Delaware, Dept Math Sci, Newark, DE 19716 USA. RP Buchanan, JL (reprint author), USN Acad, Dept Math, Annapolis, MD 21402 USA. NR 23 TC 3 Z9 3 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD DEC PY 1998 VL 35 IS 34-35 BP 4779 EP 4801 DI 10.1016/S0020-7683(98)00094-8 PG 23 WC Mechanics SC Mechanics GA 120QZ UT WOS:000075969000015 ER PT J AU Browning, SL Lodge, J Price, RR Schelleng, J Schoen, PE Zabetakis, D AF Browning, SL Lodge, J Price, RR Schelleng, J Schoen, PE Zabetakis, D TI Fabrication and radio frequency characterization of high dielectric loss tubule-based composites near percolation SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Microscopic lipid tubules with an average aspect ratio (length/diameter) of approximately 12 were metallized electrolessly with copper or nickel-over-copper, and mixed with vinyl to make foot-square composite dielectric panels. As loadings increased the metal tubule composites displayed an onset of electrical percolation with accompanying sharp increases in real and imaginary permittivities. Gravity-induced settling of the tubules while the vinyl was drying increased true loading density at percolation threshold for nickel/copper tubules to similar to 12 vol %. This threshold was at a significantly lower loading density than that previously measured for percolation by composites containing spherical conducting particles. Qualitatively, the shape of the composite permittivity versus loading density curves followed predictions by the effective-mean field theory for conducting stick composites. Changes in permittivity of the vinyl panels were observed for several days after fabrication, and were apparently associated with solvent evaporation from the matrix. [S0021-8979(98)05723-5]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Browning, SL (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM pschoen@cbmse.nrl.navy.mil NR 16 TC 40 Z9 40 U1 2 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 6109 EP 6113 DI 10.1063/1.368925 PG 5 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100041 ER PT J AU Cukauskas, EJ Allen, LH AF Cukauskas, EJ Allen, LH TI Paraconductivity in YBa2Cu3O7 and YBa2Cu3O7 thin film composites with cerium oxide and gold SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID EXCESS ELECTRICAL-CONDUCTIVITY; INHOMOGENEOUS SUPERCONDUCTORS; FLUCTUATION CONDUCTIVITY; TEMPERATURE; RESISTIVITY; TRANSITION; INSITU; STATE; TC AB The paraconductivity for thin films of YBa2Cu3O7 and composites of YBCO with CeO2 and gold was investigated and analyzed using the Aslamazov and Larkin theory. Plain YBCO thin films sputter deposited on MgO, SrTiO3, and yttrium stabilized zirconium typically showed no dimensional crossover, were described by three dimensional (3D) fluctuation conductivity, and had a critical slope just above the critical region in agreement with the prediction of theory. With few exceptions, the CeO2 and gold composite films showed a dimensional crossover and a reduced critical exponent. The change in dimensionality was typically from 3D to two dimensional (2D) fluctuation conductivity. These composite films all had reduced values for the critical exponent which we attribute to an enlarged or extended critical region. This is in agreement with the critical current response of these composites to small magnetic fields. Additionally, the composites showed a two step transition in the paraconductivity and a minimum below the critical region. The subsequent fall- off to the zero resistance state was characterized by two different slopes. Lastly, the paraconductivity was related to film degradation resulting from photoresist processing and time storage. Dimensionality changes were observed due to this degradation. (C) 1998 American Institute of Physics. [S0021-8979(98)09723-0]. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RP Cukauskas, EJ (reprint author), USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. NR 25 TC 20 Z9 20 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 6187 EP 6194 DI 10.1063/1.368935 PG 8 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100053 ER PT J AU Plant, WJ Keller, WC Hesany, V Hayes, K Hoppel, KW Blanc, TV AF Plant, WJ Keller, WC Hesany, V Hayes, K Hoppel, KW Blanc, TV TI Measurements of the marine boundary layer from an airship SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID RADAR CROSS-SECTION; ATMOSPHERIC SURFACE-LAYER; WIND-SPEED; SATELLITE SCATTEROMETER; DRAG COEFFICIENT; MODEL FUNCTION; HEAT-FLUX; OCEAN; STRESS; SEA AB In 1992 and 1993, the authors made measurements of the marine boundary layer off the coast of Oregon from an airship. In 1992, these measurements consisted of coherent microwave backscatter measurements at K-u band taken from the gondola of the airship and micrometeorological and wave height measurements made from an airborne platform suspended by a cable 65 m below the gondola so that it was between 5 and 20 m above the sea surface. In 1993, an infrared imaging system was added to the suite of instruments operated in the gondola and two narrowbeam infrared thermometers were mounted in the suspended platform. In both years, a sonic anemometer and a fast humidity sensor were carried on the suspended platform and used to measure surface layer fluxes in the atmosphere above the ocean. A laser altimeter gave both the altitude of the suspended platform and a point measurement of wave height. By operating ail these instruments together from the slow-moving airship, the authors were able to measure atmospheric fluxes, microwave cross sections and Doppler characteristics, air and sea surface temperatures, and wave heights simultaneously and coincidentally at much higher spatial resolutions than had been possible before. Here the authors document the methods and present observations of the neutral drag coefficient between wind speeds of 2 and 10 m s(-1), the relationship between the wind vector and the microwave cross section, and the effect of a sharp sea surface temperature front on both the wind vector and the microwave cross section. The drag coefficients first decrease with increasing wind speed, then reach a minimum and begin to increase with further increases in the wind speed. The values of the drag coefficient at very low wind speeds are higher than those given by Smith, however, and the minimum drag coefficient seems to occur somewhat above the wind speed he indicates. The authors show that their measured azimuthally averaged cross sections fall somewhat below the SASS LI model function of Wentz et al. at low wind speeds but are rather close to that model at higher wind speeds. Coefficients describing the dependence of the cross section on azimuth angle are generally close to those of SASS II. The azimuthally averaged cross sections generally fall within the 90% confidence interval of the model function based on friction velocity recently proposed by Weissman et al. but are often near the upper limit of this interval. Somewhat surprisingly, a residual dependence on atmospheric stratification is found in the neutral drag coefficients and in the microwave cross sections when plotted against a neutral wind speed obtained using the Businger-Dyer stability corrections. This indicates that these corrections are not adequate over the ocean for stable conditions and the authors suggest that wave-induced shear near the surface may be the reason. Finally, it is shown that winds around a sea surface temperature front can rapidly change direction and that the microwave cross section follows this change except very near the front where it becomes more isotropic than usual. C1 Univ Washington, Appl Phys Lab, Seattle, WA 98105 USA. USN, Res Lab, Washington, DC 20375 USA. RP Univ Washington, Appl Phys Lab, 1013 NE 40th St, Seattle, WA 98105 USA. EM plant@apl.washington.edu NR 32 TC 22 Z9 23 U1 0 U2 1 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 DEC PY 1998 VL 15 IS 6 BP 1433 EP 1458 DI 10.1175/1520-0426(1998)015<1433:MOTMBL>2.0.CO;2 PG 26 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 165LM UT WOS:000078522500016 ER PT J AU Miao, MS Van Camp, PE Van Doren, VE Ladik, JJ Mintmire, JW AF Miao, MS Van Camp, PE Van Doren, VE Ladik, JJ Mintmire, JW TI First-principles calculation of the conformation and electronic structure of polyparaphenylene SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DENSITY-FUNCTIONAL CALCULATIONS; CRYSTAL-STRUCTURE; PHASE-TRANSITION; CONJUGATED POLYMERS; DIFFRACTION DATA; POLY(PARA-PHENYLENE); POLYPHENYLS; POLY(P-PHENYLENE); POLYACETYLENE; CHAINS AB In this article, an all-electron first-principles total energy calculation with Gaussian-type functions for the wave functions, for the exchange correlation potential, and for the charge density has been applied for single chains of polyparaphenylene (PPP). A local-density approximation within a helical band structure approach has been used. The calculated torsional potential shows a minimum at the torsion angle of 34.8 degrees. The internal coordinates were optimized in the equilibrium conformation and are in good agreement with experimental and other theoretical results. The calculated direct band gap is 2.54 eV compared with the experimental result from UPS spectra of 3.4 eV for the gas phase. The band structure strongly depends on the conformation which suggests that the electronic properties can be modified in a wide range through doping or addition of side groups. (C) 1998 American Institute of Physics. [S0021-9606(98)30743-6]. C1 Univ Antwerp, Dept Phys, B-2020 Antwerp, Belgium. Univ Erlangen Nurnberg, Chair Theoret Chem, D-91058 Erlangen, Germany. Univ Erlangen Nurnberg, Lab Natl Fdn Canc Res, D-91058 Erlangen, Germany. USN, Res Lab, Washington, DC 20375 USA. RP Univ Antwerp, Dept Phys, B-2020 Antwerp, Belgium. OI Mintmire, John/0000-0002-6551-0349 NR 56 TC 34 Z9 35 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 1 PY 1998 VL 109 IS 21 BP 9623 EP 9631 DI 10.1063/1.477624 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 141MN UT WOS:000077147900046 ER PT J AU Lean, J Rind, D AF Lean, J Rind, D TI Climate forcing by changing solar radiation SO JOURNAL OF CLIMATE LA English DT Review ID TROPOSPHERE-STRATOSPHERE SYSTEM; SEA-SURFACE TEMPERATURE; IRRADIANCE VARIATIONS; MAUNDER MINIMUM; PRECIPITATION FLUCTUATIONS; LUMINOSITY VARIATIONS; DECADAL VARIABILITY; BRIGHTNESS CHANGES; CIRCULATION MODEL; CYCLE VARIATION AB By how much does changing radiation from the sun influence the earth's climate. presently and in the recent past, compared with other natural and anthropogenic processes? Current knowledge of the amplitudes and timescales of solar radiative output variability needed to address this question is described from contemporary solar monitoring and historical reconstructions. The 17-yr observational database of space-based solar monitoring exhibits an Il-yr irradiance cycle with amplitude of about 0.1%. Larger amplitude solar total radiative output changes-of 0.24% relative to present levels-are estimated for the seventeenth-century Maunder Minimum by parameterizing the variability mechanisms identified for the Il-yr cycle, using proxies of solar and stellar variability. The 11- and 22-yr periods evident in solar activity proxies appear in many climate and paleoclimate records, and some solar and climate time series correlate strongly over multidecadal and centennial timescales. These statistical relationships suggest a response of the climate system to the changing sun. The correlation of reconstructed solar irradiance and Northern Hemisphere (NH) surface temperature anomalies is 0.86 in the pre industrial period from 1610 to 1800, implying a predominant solar influence. Extending this correlation to the present suggests that solar forcing may have contributed about half of the observed 0.55 degrees C surface warming since 1900 and one-third of the warming since 1970. Climate model simulations using irradiance reconstructions provide a tool with which to identify potential physical mechanism for these implied connections. An equilibrium simulation by the Goddard Institute for Space Studies GCM predicts an NH surface temperature change of 0.51 degrees C for a 0.25% solar irradiance reduction, in general agreement with the preindustrial parameterization. But attributing a significant fraction of recent climate warming to solar forcing presents serious ambiguities about the impact of increasing greenhouse gas concentrations whose radiative forcing has been significantly larger than solar forcing over this time period. Present inability to adequately specify climate forcing by changing solar radiation has implications for policy making regarding anthropogenic global change, which must be detected against natural climate variability. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Lean, J (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7673L, Washington, DC 20375 USA. EM lean@demeter.nrl.navy.mil OI Lean, Judith/0000-0002-0087-9639 NR 145 TC 137 Z9 145 U1 2 U2 23 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 DEC PY 1998 VL 11 IS 12 BP 3069 EP 3094 DI 10.1175/1520-0442(1998)011<3069:CFBCSR>2.0.CO;2 PG 26 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 151ZY UT WOS:000077751700001 ER PT J AU Everstine, GC Gaunaurd, GC Huang, H AF Everstine, GC Gaunaurd, GC Huang, H TI Acoustic scattering by two submerged spherical shells: Numerical validation SO JOURNAL OF COMPUTATIONAL ACOUSTICS LA English DT Article ID FLUID STRUCTURE INTERACTION; SOUND-SCATTERING AB We validate. using a coupled finite element/boundary element computer code, a recently-developed(1) series solution for the structural acoustics problem of scattering from two submerged spherical elastic shells. Although the general purpose computational tools for acoustic scattering have never been restricted to single scatterers, the availability of the series solution provides, for the first time, the mutual validation of both exact and numerical approaches for a multiple elastic scatterer problem. The excellent agreement between the two solutions presented thus allows this problem to be added to the short list of existing benchmark structural acoustics problems possessing an analytic solution. For the purposes of this comparison, the direction of incidence is taken as parallel with the axis joining the two shells. The numerical solution uses the NASHUA code, which couples a finite element shell model of the two shells with a boundary element model of the surrounding fluid. The exact solution is found by expanding in terms of classical modal series and uses the addition theorem for the spherical wave functions. The exact solution requires coupling coefficients that are expressed in terms of sums of products of Wigner 3-j symbols (or Clebsch-Gordan coefficients). C1 USN, Warface Ctr, Carderock Div, Bethesda, MD 20817 USA. RP Everstine, GC (reprint author), USN, Warface Ctr, Carderock Div, Bethesda, MD 20817 USA. NR 22 TC 1 Z9 1 U1 2 U2 5 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-396X J9 J COMPUT ACOUST JI J. Comput. Acoust. PD DEC PY 1998 VL 6 IS 4 BP 421 EP 434 DI 10.1142/S0218396X98000272 PG 14 WC Acoustics; Mathematics, Interdisciplinary Applications SC Acoustics; Mathematics GA 161BE UT WOS:000078267400003 ER PT J AU Battaile, CC Srolovitz, DJ Butler, JE AF Battaile, CC Srolovitz, DJ Butler, JE TI Atomic-scale simulations of chemical vapor deposition on flat and vicinal diamond substrates SO JOURNAL OF CRYSTAL GROWTH LA English DT Article ID SCANNING-TUNNELING-MICROSCOPY; CVD-GROWN DIAMOND; HOMOEPITAXIAL DIAMOND; 113 FACETS; AB-INITIO; SURFACES; FILMS; RECONSTRUCTION; MORPHOLOGY; MECHANISM AB The growth of diamond by chemical vapor deposition was simulated on nine substrates corresponding to Bat and slightly miscut (1 0 0), (1 1 0), and (1 1 1) surfaces. The kinetics of the important surface reactions were input to a three-dimensional atomic-scale kinetic Monte Carlo model of him growth in various environments. The effects of the atmosphere near the growth surface and the atomic structure of the surface on growth behavior are ascertained. The differences in bonding configuration at the various atomic surface features have a strong effect on growth behavior, even when steric effects are not considered. Surface features that can grow by the addition of only one C atom from the gas grow faster than features that need more C atoms to propagate. This impacts not only the growth behavior of the flat (1 0 0), (1 1 0), and (1 1 1) faces which require one, two, and three C atoms to nucleate growth layers, respectively but also the growth of miscut substrates which contain steps that can grow much more quickly than the Bat terraces. Acetylene is particularly important to growth on several of the surface orientations (e.g., (1 1 1)) because it aids in the formation of C clusters on the surface. The bonding geometries of the surface features on each of the nine substrate orientations are described, and their impact on growth behavior is demonstrated by altering the acetylene content of the gas near the growth surface. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. USN, Res Lab, Gas Surface Dynam Sect, Washington, DC 20375 USA. RP Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. EM srol@umich.edu RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 46 TC 36 Z9 36 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 EI 1873-5002 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1998 VL 194 IS 3-4 BP 353 EP 368 DI 10.1016/S0022-0248(98)00685-X PG 16 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 143WL UT WOS:000077280400012 ER PT J AU Rappaport, HL AF Rappaport, HL TI Localized modes with zonal neutral wind, diffusion, and shear in equatorial spread F SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INHOMOGENEOUS ELECTRIC-FIELD; EXB INSTABILITY; LINEAR-THEORY; REGION; IONOSPHERE; DRIFTS AB The effects of a zonal neutral wind, diffusion, and shear flow on perturbations in equatorial spread F (ESF) are examined. A. central goal of this work is to consider effects that arise from inhomogeneity of the ionosphere along the magnetic field lines of the Earth. The perturbations discussed here have cross-field wavelengths which are small compared with the cross-field inhomogeneity scales of the equilibrium. Inhomogeneity in the zonal wind velocity along a magnetic field line gives rise to a vertical Pedersen current. When the effects of shear are neglected, this current can increase or decrease the growth rate of the perturbations by an amount proportional to the difference between the zonal wind speed and the equilibrium plasma drift speed divided by the ionospheric scale height. Diffusion terms proportional to the product of the ion cross-field mobility and the electron parallel mobility are found to increase the growth rate of ESF by reducing molecular ion region loading. Effects of shear are considered using the model of Fu et al. [1986], in which the perturbations are driven to smaller scales over time. The "quasi-local" temporal behavior of the cold kilometer scale instability is described, while retaining, in an approximate way, the effects of the cross-field scale size dependent mapping efficiency described by Rappaport [1996]. In the diffusion regime a variational principle describing the decay of the perturbations is given. This model incorporates the effects of both parallel and cross-field diffusions, as well as inhomogeneity along the field Line. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Rappaport, HL (reprint author), USN, Res Lab, Div Plasma Phys, Code 6794,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 28 TC 4 Z9 4 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 DEC 1 PY 1998 VL 103 IS A12 BP 29137 EP 29154 DI 10.1029/98JA02678 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 149MD UT WOS:000077608400003 ER PT J AU Bucsela, EJ Cleary, DD Dymond, KF McCoy, RP AF Bucsela, EJ Cleary, DD Dymond, KF McCoy, RP TI Atomic and molecular emissions in the middle ultraviolet dayglow SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ELECTRON-IMPACT IONIZATION; PHOTOIONIZATION CROSS-SECTIONS; NOCTURNAL F-REGION; SATELLITE MEASUREMENTS; RATE CONSTANTS; VIBRATIONAL POPULATIONS; EINSTEIN COEFFICIENTS; NII-2143-A EMISSION; ROCKET OBSERVATIONS; COORDINATED ROCKET AB Dayglow spectra in the middle ultraviolet, obtained during a sounding rocket flight from White Sands Missile Range in 1992, have been analyzed to determine the altitude distributions of thermospheric atomic and molecular species and to address a number of problems related to airglow excitation mechanisms. Among the atomic and molecular profiles retrieved are the N-2 second positive, N-2 Vegard-Kaplan and NO gamma band systems, and the OI 297.2 nm, OII 247.0 nm, and NII 214.3 nm emissions. A self-consistent study of the emission profiles was conducted by comparing observed intensities with one another and to forward models. Model photoelectron and photon fluxes were generated by the field line interhemispheric plasma model (FLIP) and two solar flux models. Neutral densities were obtained from mass-spectrometer/incoherent scatter (MSIS)-90. The results from the data analysis suggest that the major species' densities are within 40% of MSIS values. Evidence for the accuracy of the modeled densities and fluxes is seen in the close agreement between the calculated and observed intensities of the N-2 second positive emission. Analysis of the OI 297.2 nm emission shows that the reaction N-2(A) + O is the dominant source of O(S-1) in the daytime thermosphere. The data imply that the vibrationally averaged yield of O(S-1) from the reaction is 0.43 +/- 0.12, which is smaller than the laboratory value measured for the N,(A, nu' = 0) level. The cause of a disagreement between model and data for the Vegard-Kaplan emission is unclear, but the discrepancy can be eliminated if the N,(A) + O quenching coefficient or the A state lifetime is increased by a factor between 2 and 4. The observed intensity of OII 247.0 nm is greater than expected by a factor of 2, implying possible inadequacies in the EUVAC and/or EUV91 solar models used in the analysis. C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Bucsela, EJ (reprint author), Raytheon STX Corp, 4400 Forbes Blvd, Lanham, MD 20706 USA. EM bucsela@stx.com NR 83 TC 13 Z9 13 U1 2 U2 2 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 DEC 1 PY 1998 VL 103 IS A12 BP 29215 EP 29228 DI 10.1029/98JA01995 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 149MD UT WOS:000077608400009 ER PT J AU Kang, YK Kim, MH Park, HC Agrawal, B AF Kang, YK Kim, MH Park, HC Agrawal, B TI Multi-modal vibration control of laminated composite plates using piezoceramic sensors/actuators SO JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES LA English DT Article AB Multi-modal vibration control of the cantilevered laminated composite plates using collocated piezoceramic sensors/actuators is analyzed theoretically and verified experimentally for various fiber orientations. Impact on the stiffness and the damping properties by varying the stacking sequence of [theta(4)/0(2)/90(2)](S) for the laminated composite plate is studied. The finite element method is used for the dynamic analysis of the plates with and without the piezoceramics. Natural frequencies and modal damping of the first bending and the first torsional modes are predicted theoretically by taking into account damping and stiffness of the adhesive layer and the piezoceramics in the modeling. Active modal damping of the first bending and the first torsional modes are measured experimentally. It is demonstrated that the active control is more effective for the structure with higher stiffness when the feedback gain is large, whereas it follows trends of the passive control by tailoring when the gain is small. C1 Univ Manchester, Manchester M13 9PL, Lancs, England. LG Ind Syst Co Ltd, Seoul, South Korea. USN, Postgrad Sch, Monterey, CA USA. RP Park, HC (reprint author), Pohang Univ Sci & Technol, POSTECH, Dept Mech Engn, Pohang 790784, Kyungbuk, South Korea. NR 5 TC 1 Z9 1 U1 0 U2 2 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 1045-389X J9 J INTEL MAT SYST STR JI J. Intell. Mater. Syst. Struct. PD DEC PY 1998 VL 9 IS 12 BP 988 EP 990 PG 3 WC Materials Science, Multidisciplinary SC Materials Science GA 265WA UT WOS:000084267900003 ER PT J AU Suits, BH Garroway, AN Miller, JB AF Suits, BH Garroway, AN Miller, JB TI Surface and gradiometer coils near a conducting body: The lift-off effect SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE magnetic resonance; NMR; NQR; MRI; surface coils; sensitivity; signal-to-noise ratio; lift-off; gradiometer; small loop antenna; dissipative media ID NOISE AB The use of surface coils in magnetic resonance is widespread, Examples include MRI, detection of subsurface aquifers by NMR, and, more recently, landmine detection by nuclear quadrupole resonance. In many of these cases a finite-sized sample to be examined is contained within a larger medium that is a poor electrical conductor, and eddy currents induced by the RF fields provide a loss mechanism that reduces the effective quality factor Q of the transmitter and receiver coils. Here the losses induced in a circular surface coil (a horizontal loop antenna) separated a distance from a dissipative medium are calculated and compared to measurements. It is shown that often the overall efficiency of the coil for magnetic resonance can be improved by displacing the coil away from the conducting medium a prescribed "lift-off" distance. The use of a gradiometer as a surface coil is also examined, and it is shown by theory and experiment that in certain circumstances such a gradiometer can be more efficient than a conventional surface coil for inspection of conducting media. (C) 1998 Academic Press. C1 Michigan Technol Univ, Dept Phys, Houghton, MI 49931 USA. USN, Res Lab, Washington, DC 20375 USA. RP Suits, BH (reprint author), Michigan Technol Univ, Dept Phys, 1400 Townsend Dr, Houghton, MI 49931 USA. NR 16 TC 38 Z9 40 U1 0 U2 8 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD DEC PY 1998 VL 135 IS 2 BP 373 EP 379 DI 10.1006/jmre.1998.1608 PG 7 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 151MZ UT WOS:000077725400010 PM 9878466 ER PT J AU Vachet, RW Hartman, JAR Callahan, JH AF Vachet, RW Hartman, JAR Callahan, JH TI Ion-molecule reactions in a quadrupole ion trap as a probe of the gas-phase structure of metal complexes SO JOURNAL OF MASS SPECTROMETRY LA English DT Article DE electrospray; metal complexes; ion-molecule reactions; quadrupole ion trap; tandem mass spectrometry ID ELECTROSPRAY MASS-SPECTROMETRY; CYCLOTRON RESONANCE SPECTROSCOPY; TRANSITION-METAL; ALKALINE-EARTH; ORGANOMETALLIC CHEMISTRY; IRON PENTACARBONYL; ORGANIC-MOLECULES; DIMER COMPLEXES; DIIMINE LIGANDS; PEPTIDE IONS AB A method is described in which the coordination number in metal complexes can be determined using ion-molecule reactions in a quadrupole ion trap mass spectrometer. Complexes of first-row transition metals in the +2 oxidation state, including manganese through zinc, are electrosprayed, isolated in the ion trap and allowed to react with gases, The coordination number is ascertained by observing the reagent ligands that successfully react with the complex. It was generally observed that six-coordinate complexes are unreactive, five-coordinate complexes react with pyridine and ethylamine, four-coordinate complexes react with pyridine, ethylamine and ammonia and three-coordinate complexes react with all the reagent ligands studied, including water and methanol. The order of reactivity for a given complex reacting with tbe various reagent ligands is found to follow the order of the electron-donating ability of the reagent ligands. In addition, the effect of the metal center on the reactivity of the complexes in the gas phase is analogous to solution-phase trends; electronic structure strongly influences the gas-phase reactions. These results were then used to predict the complexation behavior of novel podand ligands for which condensed phase information is not available. The results indicate that ion-molecule chemistry in the gas phase may be useful in predicting the interactions between novel multidentate ligands and metals in solution. (C) 1998 John Wiley & Sons, Ltd. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP Callahan, JH (reprint author), USN, Res Lab, Div Chem, Code 6113, Washington, DC 20375 USA. NR 61 TC 73 Z9 74 U1 0 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1076-5174 J9 J MASS SPECTROM JI J. Mass Spectrom. PD DEC PY 1998 VL 33 IS 12 BP 1209 EP 1225 DI 10.1002/(SICI)1096-9888(199812)33:12<1209::AID-JMS738>3.0.CO;2-W PG 17 WC Biophysics; Chemistry, Organic; Spectroscopy SC Biophysics; Chemistry; Spectroscopy GA 150WW UT WOS:000077689800008 ER PT J AU Lambrakos, SG Milewski, JO AF Lambrakos, SG Milewski, JO TI A general approach based on constrained parameter-optimization for the implicit representation of information concerning welding processes SO JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE LA English DT Article DE complex morphology; constraints; deep penetration; elliptic problem; generating function; parameter optimization ID GEOMETRIC CONSTRAINTS; PENETRATION AB An analysis of weld morphology which typically occurs in deep penetration welding processes using electron or laser beams is presented. The method of analysis is based on geometric constraints with formal mathematical foundation within the theory of constrained parameter optimization. The analysis presented in this report serves as an example of the application of the geometric-constraints method to the analysis of weld fusion boundary morphology where there can be fragmented and incomplete information concerning material properties and only approximate information concerning the character of energy deposition, thus making a direct first principals approach difficult. A significant aspect of the geometric-constraints method is that it permits the implicit representation of information concerning temperature dependence of material properties and of coupling between heat transfer and fluid convection occurring in the weld meltpool. C1 USN, Div Mat Sci & Technol, Res Lab, Washington, DC 20375 USA. Univ Calif Los Alamos Natl Lab, Met Grp, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Lambrakos, SG (reprint author), USN, Div Mat Sci & Technol, Res Lab, Code 6324, Washington, DC 20375 USA. NR 10 TC 0 Z9 0 U1 1 U2 1 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9495 J9 J MATER ENG PERFORM JI J. Mater. Eng. Perform. PD DEC PY 1998 VL 7 IS 6 BP 761 EP 771 DI 10.1361/105994998770347332 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 151PV UT WOS:000077730400009 ER PT J AU Brook, I Frazier, EH AF Brook, I Frazier, EH TI Microbiology of liver and spleen abscesses SO JOURNAL OF MEDICAL MICROBIOLOGY LA English DT Article ID SPLENIC ABSCESS; THERAPEUTIC STRATEGIES; PERCUTANEOUS DRAINAGE; DIAGNOSIS AB To study the aerobic and anaerobic microbiology of liver and spleen abscesses and correlate the results with predisposing factors, potential causes and routes of infection, clinical and laboratory data of 48 patients with liver abscesses and 29 with spleen abscesses treated between 1970 and 1990 were reviewed retrospectively. In liver abscesses, a total of 116 isolates (2.4 isolates/specimen) was obtained; 43 were aerobic and facultative species (0.9 isolates/specimen) and 73 were anaerobic species or microaerophilic streptococci (1.5 isolates/specimen). Aerobic bacteria only were isolated from 12 (25%) abscesses, anaerobic bacteria only from eight (17%), and mixed aerobic and anaerobic bacteria from 28 (58%); polymicrobial infection was present in 38 (79%). The predominant aerobic and facultative isolates were Escherichia coli (11 isolates), Streptococcus group D (8), Klebsiella pneumonia (5) and Staphylococcus aureus (4). The predominant anaerobes were Peptostreptacoccus spp. (18 isolates), Bacteroides spp. (13), Fusobacterium spp. (10), Clostridium spp. (10) and Prevotella spp. (4). There were 12 isolates of microaerophilic streptococci. S. aureus and beta-haemolytic streptococci were associated with trauma; Streptococcus group D, Ii. pneumoniae and Clostridium spp. with biliary disease; and Bacteroides spp. and Clostridium spp. with colonic disease. In splenic abscesses, a total of 56 isolates (1.9 isolates/specimen) was obtained; 23 were aerobic and facultative species (0.8 isolates/specimen), 31 were anaerobic species or micro-aerophilic streptococci (1.1 isolates/specimen) and two were Candida albicans. Aerobic bacteria only were isolated from nine (31%) abscesses, anaerobic bacteria from eight (28%), mixed aerobic and anaerobic bacteria from 10 (34%) and C. albicans in two (7%); polymicrobial infection was present in 16 (55%). The predominant aerobic and facultative isolates were E. coli (5 isolates), Proteus mirabilis (3), Streptococcus group D (3), K. pneumoniae (3) and S. aureus (4). The predominant anaerobes were Peptostreptococcus spp. (11 isolates), Bacteroides spp. (5), Fusobacterium spp. (3) and Clostridium spp. (3). S. aureus, K. pneumoniae and Streptococcus group D were associated with endocarditis, E. coli with urinary tract and abdominal infection, Bacteroides spp. and Clostridium spp. with abdominal infection and Fusobacterium spp. with respiratory infection. C1 Naval Hosp, Dept Pediat, Bethesda, MD USA. Naval Hosp, Dept Infect Dis, Bethesda, MD USA. RP Brook, I (reprint author), POB 70412, Chevy Chase, MD 20813 USA. NR 20 TC 72 Z9 76 U1 0 U2 3 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0022-2615 J9 J MED MICROBIOL JI J. Med. Microbiol. PD DEC PY 1998 VL 47 IS 12 BP 1075 EP 1080 PG 6 WC Microbiology SC Microbiology GA 143QE UT WOS:000077266200007 PM 9856643 ER PT J AU Song, G Longman, RW Cai, L AF Song, G Longman, RW Cai, L TI Integrated adaptive-robust control of robot manipulators SO JOURNAL OF ROBOTIC SYSTEMS LA English DT Article ID SLIP FRICTION COMPENSATION AB In this article, an integrand adaptive-robust approach along with a smooth adaptive-robust friction compensation strategy are applied to tracking control of robot manipulators with joint stick-slip friction. The designed controller takes advantage of both adaptive and robust approaches. It has the ability to learn and the ability to reject disturbance and to handle various uncertainties including stick-slip friction. The uncertainties due to unknown robot link parameters, unknown viscous friction coefficient, and unknown maximum static friction, which are linear in parameters, are compensated by the integrated adaptive-robust control method. On the other hand, the exponential friction (used to model the Stribeck effect: the downward bend of friction torque at low velocities), which are nonlinear in parameters, and external disturbances, are compensated by a robust compensator with a self-learning upper bounding function when no a priori knowledge on the exponential friction and disturbances are available. The employed robust compensators produce smooth control action, and avoid motion intermittency, which are commonly associated with stick-slip friction. The proposed controller guarantees global asymptotic stability of the closed-loop system, as proved by Lyapunov's direct method. (C) 1998 John Wiley & Sons, Inc. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. Columbia Univ, Dept Mech Engn, New York, NY 10027 USA. Hong Kong Univ Sci & Technol, Dept Mech Engn, Kowloon, Hong Kong. RP Song, G (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. NR 18 TC 5 Z9 5 U1 2 U2 6 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0741-2223 J9 J ROBOTIC SYST JI J. Robot. Syst. PD DEC PY 1998 VL 15 IS 12 BP 699 EP 712 PG 14 WC Robotics SC Robotics GA 139DK UT WOS:000077012500003 ER PT J AU Perry, HM Johnson, D Trigg, C Eleuterius, C Warren, J AF Perry, HM Johnson, D Trigg, C Eleuterius, C Warren, J TI Application of remote sensing to settlement of Callinectes sapidus megalopae in the Mississippi bight SO JOURNAL OF SHELLFISH RESEARCH LA English DT Article; Proceedings Paper CT Workshop on Spatial Data and Remote Sensing in Invertebrate Fisheries held in conjunction with the 89th Annual Meeting of the National-Shellfisheries-Association CY APR 19-20, 1997 CL FT WALTON BEACH, FLORIDA SP Natl Shellfisheries Assoc, Natl Environm Satellite Data & Informat Serv, US Army Corps Engineers Waterways Expt Stn DE blue crab; Gulf of Mexico; currents; wind stress ID EASTERN GULF; MEXICO; CIRCULATION; PATTERNS AB Blue crab larvae undergo zoeal and megalopal development in offshore waters of the Gulf of Mexico. The surface residing planktonic larvae are dependent upon advective currents to return them from sea at the appropriate time for settlement in near-shore habitats. Settlement is episodic. The periodicity of settlement is similar over years; however, magnitude is highly variable. A numerical model of the gulf was used to determine advective pathways and environmental forcing conditions affecting successful returns. Two factors were found to be important: wind stress and timing of the break-off of Loop Current eddies. Interannual variation in wind stress was most significant. C1 Gulf Coast Res Lab, Ocean Springs, MS 39566 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Perry, HM (reprint author), Gulf Coast Res Lab, Ocean Springs, MS 39566 USA. NR 18 TC 4 Z9 4 U1 0 U2 0 PU NATL SHELLFISHERIES ASSOC PI SOUTHAMPTON PA C/O DR. SANDRA E. SHUMWAY, NATURAL SCIENCE DIVISION, SOUTHAMPTON COLLEGE, SOUTHAMPTON, NY 11968 USA SN 0730-8000 J9 J SHELLFISH RES JI J. Shellfish Res. PD DEC PY 1998 VL 17 IS 5 BP 1439 EP 1442 PG 4 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 187WN UT WOS:000079811400013 ER PT J AU Ladner, SD Arnone, RA AF Ladner, SD Arnone, RA TI Monitoring coastal environments using satellite time series SO JOURNAL OF SHELLFISH RESEARCH LA English DT Article; Proceedings Paper CT Workshop on Spatial Data and Remote Sensing in Invertebrate Fisheries held in conjunction with the 89th Annual Meeting of the National-Shellfisheries-Association CY APR 19-20, 1997 CL FT WALTON BEACH, FLORIDA SP Natl Shellfisheries Assoc, Natl Environm Satellite Data & Informat Serv, US Army Corps Engineers Waterways Expt Stn DE time series; satellite; sea surface ID ATTENUATION COEFFICIENT; WATERS AB Databases developed from satellite products can be used to understand long- and short-term oceanographic processes. An automated processing system developed for the creation of co-registered and satellite-derived image databases of sea surface temperature and bio-optical parameters from the Advanced Very High-Resolution Radiometer (AVHRR) and Coastal Zone Color Scanner (CZCS) sensors is presented. We have applied database techniques toward predicting fish locations for the West Coast of the United States. We present a user interactive graphical interface to display the databases visually and to connect a series of fish behavior rules by performing logical operations. This program provides a real-time interactive display for testing and developing an understanding of fish behavior and location. C1 Planning Syst Inc, Slidell, LA 70458 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Ladner, SD (reprint author), Planning Syst Inc, Slidell, LA 70458 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU NATL SHELLFISHERIES ASSOC PI SOUTHAMPTON PA C/O DR. SANDRA E. SHUMWAY, NATURAL SCIENCE DIVISION, SOUTHAMPTON COLLEGE, SOUTHAMPTON, NY 11968 USA SN 0730-8000 J9 J SHELLFISH RES JI J. Shellfish Res. PD DEC PY 1998 VL 17 IS 5 BP 1445 EP 1450 PG 6 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 187WN UT WOS:000079811400015 ER PT J AU Marshall, L Heller, LM AF Marshall, L Heller, LM TI Transient-evoked otoacoustic emissions as a measure of noise-induced threshold shift SO JOURNAL OF SPEECH LANGUAGE AND HEARING RESEARCH LA English DT Article; Proceedings Paper CT 20th Midwinter Research Meeting of the Association-for-Research-in-Otolaryngology CY FEB 01-06, 1997 CL ST PETERSBURG, FLORIDA SP Assoc Res Otolaryngol DE temporary threshold shift (TTS); otoacoustic emissions; noise-induced hearing loss; hearing conservation; transient-evoked otoacoustic emissions; click-evoked otoacoustic emissions (TEOAE, TOAE, COAE) ID MIDDLE-EAR PRESSURE; EXPOSURE; HUMANS AB Otoacoustic emissions and behavioral hearing thresholds were measured before and after exposure to a 10-min, 105-dB SPL, half-octave band of noise centered at 1.414 kHz. Along a single recovery function, transient-evoked otoacoustic-emission (TEOAE) measurements made with 74-dB pSPL nonlinear click ensembles were alternated with a Bekesy threshold-tracking procedure. Each of the 14 participants with normal hearing underwent 2 hour-long temporary-threshold shift (TTS) sessions as well as 2 pretest sessions and a posttest session. The Bekesy test Frequency was fixed at 2.0 kHz, whereas emissions were analyzed in half octave bandwidths with center frequencies ranging from 0.707 to 5.656 kHz. Results showed that (a) the maximum temporary emission shifts (TES) were half to 1 octave above the exposure frequency; (b) the 4.7-dB average temporary emission shift magnitude at approximately 2 min postexposure was less than half of the 1 1.7-dB average TTS; (c) the average recovery times for emissions and hearing thresholds were similar (188 vs. 186 min); and (d) the average TTS magnitude along the recovery function was predictable from TES magnitude. It is concluded that both TEOAEs and Bekesy thresholds reveal the same aspects of postexposure inner-ear changes. C1 USN, Submarine Med Res Lab, Groton, CT 06349 USA. RP Marshall, L (reprint author), USN, Submarine Med Res Lab, Box 900,Subase NLON, Groton, CT 06349 USA. EM marshall@nsmrl.navy.mil NR 25 TC 20 Z9 21 U1 1 U2 2 PU AMER SPEECH-LANGUAGE-HEARING ASSOC PI ROCKVILLE PA 10801 ROCKVILLE PIKE, ROCKVILLE, MD 20852-3279 USA SN 1092-4388 J9 J SPEECH LANG HEAR R JI J. Speech Lang. Hear. Res. PD DEC PY 1998 VL 41 IS 6 BP 1319 EP 1334 PG 16 WC Audiology & Speech-Language Pathology; Linguistics; Rehabilitation SC Audiology & Speech-Language Pathology; Linguistics; Rehabilitation GA 145JV UT WOS:000077368500009 PM 9859887 ER PT J AU Huang, H Gaunaurd, GC AF Huang, H Gaunaurd, GC TI Transient diffraction of a plane step pressure pulse by a hard sphere: Neoclassical solution SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The transient diffraction of a plane step pressure pulse by a hard sphere is studied via the modal series solution in a neoclassical fashion. With the advent and availability of more powerful computers and increased sophistication of computational algorithms, it is now possible to (1) accurately compute the time histories of a sufficiently large number of terms of the modal series, and (2) use the Cesaro summation to completely eradicate the Gibbs' phenomenon effects. This approach can be utilized to obtain the diffracted field in the entire space-time region. In particular, a complete treatment is developed for the diffracted field at the shadow boundary and in its neighborhood where heretofore no satisfactory analytical solution exists. (C) 1998 Acoustical Society of America. [S0001-4966(98)06311-5]. C1 Naval Surface Warfare Ctr, Carderock Div, Bethesda, MD 20817 USA. RP Huang, H (reprint author), 13200 Overbrook Lane, Bowie, MD 20715 USA. EM gaunaurd@oasys.dt.navy.mil NR 13 TC 3 Z9 3 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD DEC PY 1998 VL 104 IS 6 BP 3236 EP 3244 DI 10.1121/1.423964 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 145JM UT WOS:000077367500015 ER PT J AU Yoo, K Yang, TC AF Yoo, K Yang, TC TI Improved vertical array performance in shallow water with a directional noise field SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SOURCE LOCALIZATION AB The detection and localization performance of a vertical array against a submerged target in shallow water can be significantly improved if the noise field is directional and the signal arrives in the null (notch) of the noise field. This often happens in a summer environment with a downward refractive sound speed profile in which the surface generated noise field exhibits a notch in the noise vertical directionality distribution at mid (e.g., 500 Hz) frequencies. Using conventional beamforming, by steering the beams to the shallow arrival angle of the target signal, the (undesired) noise which arrives at steep angles can be suppressed. However, conventional beamforming often suffers from significant signal gain degradation due to multipaths in the shallow water environment. Matched-field processing yields a theoretical signal gain by coherently processing the signal, but its ability to reject the directional noise is limited. Matched-beam processing, which is matched-field processing in the beam domain, incorporates the advantages of matched-field processing for coherent signal integration, and conventional beamforming for noise rejection. For the summer environment studied, matched-beam processing yields the highest array gain, almost a twice longer detection range, and a superior capability in detecting a deep target compared with the other two processors. This is demonstrated using simulated signal and noise fields with a full water column vertical array. [S0001-4966(98)02312-1]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Yoo, K (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 20 TC 8 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD DEC PY 1998 VL 104 IS 6 BP 3326 EP 3338 DI 10.1121/1.423972 PG 13 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 145JM UT WOS:000077367500024 ER PT J AU Stafford, KM Fox, CG Clark, DS AF Stafford, KM Fox, CG Clark, DS TI Long-range acoustic detection and localization of blue whale calls in the northeast Pacific Ocean SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID BALAENOPTERA-MUSCULUS; FUCA RIDGE; CALIFORNIA; ARRAY; JUAN AB Analysis of acoustic signals recorded from the U.S. Navy's SOund SUrveillance System (SOSUS) was used to detect and locate blue whale (Balaenoptera musculus) calls offshore in the northeast Pacific. The long, low-frequency components of these calls are characteristic of calls recorded in the presence of blue whales elsewhere in the world. Mean values for frequency and time characteristics from field-recorded blue whale calls were used to develop a simple matched filter for detecting such calls in noisy time series. The matched filter was applied to signals from three different SOSUS arrays off the coast of the Pacific Northwest to detect and associate individual calls from the same animal on the different arrays. A U.S. Navy maritime patrol aircraft was directed to an area where blue whale calls had been detected on SOSUS using these methods, and the presence of a vocalizing blue whale was confirmed at the site with field recordings from sonobuoys. [S0001-4966(98)01312-5]. C1 Oregon State Univ, Dept Fisheries & Wildlife, Newport, OR 97365 USA. NOAA, Pacific Marine Environm Lab, Newport, OR 97365 USA. USN, Command Control & Ocean Surveillance Ctr, San Diego, CA 95152 USA. RP Stafford, KM (reprint author), Oregon State Univ, Hatfield Marine Sci Ctr, Cooperat Inst Marine Resources Studies, Newport, OR 97365 USA. NR 42 TC 81 Z9 87 U1 1 U2 16 PU ACOUSTICAL SOC AMER AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD DEC PY 1998 VL 104 IS 6 BP 3616 EP 3625 DI 10.1121/1.423944 PG 10 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 145JM UT WOS:000077367500053 PM 9857519 ER PT J AU Ross, EV Amesbury, EC Barile, A Proctor-Shipman, L Feldman, BD AF Ross, EV Amesbury, EC Barile, A Proctor-Shipman, L Feldman, BD TI Incidence of postoperative infection or positive culture after facial laser resurfacing: A pilot study, a case report, and a proposal for a rational approach to antibiotic prophylaxis SO JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY LA English DT Article ID CARBON-DIOXIDE LASER; CHEMICAL PEEL; SKIN; MICROBIOLOGY; CO2-LASER; RHYTIDES; SURGERY; WOUNDS; TERM AB Background: Laser skin resurfacing (LSR) has emerged as a popular procedure for facial rejuvenation; however, there are no clear guidelines regarding systemic antibiotic prophylaxis. Objective: We attempt to provide practical guidelines for antibiotic prophylaxis in LSR based on our experiences, pharmacology, and a review of the literature. Methods: In a pilot study, four consecutive full-face LSR patients were treated without oral or topical antibiotics. The next four patients received oral prophylaxis with a narrow spectrum antibiotic. We also report the case of a severe gram-negative infection after LSR. Results: For full-face LSR, 2 of 4 consecutive patients without antibiotic prophylaxis experienced focal Staphylococcus aureus infection. The next 4 consecutive patients, who had received gram-positive oral prophylaxis, were all culture negative after 2 days. All test sites (5 of 5) were culture negative despite the absence of systemic or topical antibiotics. One patient not in the pilot study receiving gram-positive antibiotic prophylaxis experienced a gram-negative infection. Conclusion: We recommend narrow-spectrum gram-positive oral antibiotic coverage for full-face and regional LSR. C1 USN, Dept Clin Res, Naval Med Ctr San Diego, San Diego, CA 92134 USA. USN, Dept Dermatol, Naval Med Ctr San Diego, San Diego, CA 92134 USA. USN, Dept Internal Med, Naval Med Ctr San Diego, Div Infect Dis, San Diego, CA 92134 USA. RP Ross, EV (reprint author), USN, Dept Clin Res, Naval Med Ctr San Diego, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 33 TC 23 Z9 23 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0190-9622 J9 J AM ACAD DERMATOL JI J. Am. Acad. Dermatol. PD DEC PY 1998 VL 39 IS 6 BP 975 EP 981 PG 7 WC Dermatology SC Dermatology GA 143VJ UT WOS:000077277500011 PM 9843012 ER PT J AU Brown, JR Steinke, WE Zhai, J Sykes, D AF Brown, JR Steinke, WE Zhai, J Sykes, D TI Aqua-reslin (TM) droplet analysis SO JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION LA English DT Article DE aerosol droplet measurement; laser system droplet analysis; aerosol; hot wire; Aqua-Reslin (R); Teflon (R) slides; mosquito control; adulticide AB Aerosol droplets were collected, counted, and sorted using a laser system, the Army Insecticide Measuring System, Teflon(R)-coated slides, and magnesium oxide-coated slides. All droplets, for each method and replication, were generated by a London Aire 1820 or a Leco Model 1600. These data indicate that the Army Insecticide Measuring System or Teflon-coated slides are so closely similar to the laser that they could effectively be used in the field without an overwhelming loss in precision. C1 USN, Dis Vector Ecol & Control Ctr, Jacksonville, FL 32212 USA. Univ Calif Davis, Davis, CA 95616 USA. AgrEvo, Montvale, NJ 07645 USA. AgrEvo, Madison, FL USA. RP Brown, JR (reprint author), USN, Dis Vector Ecol & Control Ctr, POB 43,Naval Air Stn, Jacksonville, FL 32212 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU AMER MOSQUITO CONTROL ASSN INC PI LAKE CHARLES PA 2200 E PRIEN LAKE RD, LAKE CHARLES, LA 70601 USA SN 8756-971X J9 J AM MOSQUITO CONTR JI J. Am. Mosq. Control Assoc. PD DEC PY 1998 VL 14 IS 4 BP 467 EP 469 PG 3 WC Entomology SC Entomology GA 174BE UT WOS:000079013600018 PM 10084143 ER PT J AU Chen, L Wu, C Sun, F Yu, J AF Chen, L Wu, C Sun, F Yu, J TI Performance characteristic of fluid power converters SO JOURNAL OF THE INSTITUTE OF ENERGY LA English DT Article ID HEAT-TRANSFER LAW; ISOTHERMAL CHEMICAL ENGINES; FINITE-TIME; MAXIMUM POWER; CARNOT ENGINE; THERMODYNAMICS; WORK; EFFICIENCY; PLANTS; OUTPUT AB The endoreversible thermodynamic theory of heat engines is extended to fluid flow power converters. The useful power can be extracted from the piston and cylinder apparatus. The correlation between power output and efficiency is derived based on a linear flow resistance relationship. The influences of the piston-cylinder friction and nonlinear flow resistance relationships on the performance of the converter are also analyzed in this paper. Performance optimization is undertaken based on the overall size constraints. The paper also develops an analogy among the fluid flow power converters, endoreversible heat engines, endoreversible isothermal chemical engines, classical reversible heat engines, and the ideal motor powered by electrical battery. The results can be applied to the performance analyses and optimization for many steady-flow shaft-powered components. C1 Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. RP Wu, C (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. NR 40 TC 19 Z9 22 U1 1 U2 3 PU INST ENERGY PI LONDON PA 18 DEVONSHIRE ST PORTLAND PLACE, LONDON, ENGLAND W1N 2AU SN 0144-2600 J9 J I ENERGY JI J. Inst. Energy PD DEC PY 1998 VL 71 IS 489 BP 209 EP 215 PG 7 WC Energy & Fuels SC Energy & Fuels GA 325TM UT WOS:000087692500007 ER PT J AU Stamatos, NM Mascola, JR Kalyanaraman, VS Louder, MK Frampton, LM Birx, DL VanCott, TC AF Stamatos, NM Mascola, JR Kalyanaraman, VS Louder, MK Frampton, LM Birx, DL VanCott, TC TI Neutralizing antibodies from the sera of human immunodeficiency virus type 1-infected individuals bind to monomeric gp120 and oligomeric gp140 SO JOURNAL OF VIROLOGY LA English DT Article ID HUMAN MONOCLONAL-ANTIBODY; CROSS-LINKED COMPLEXES; ENVELOPE GLYCOPROTEIN; INFECTIOUS-DISEASES; PRIMARY ISOLATE; NATIVE GP120; HIV-1 GP120; EPITOPES; VACCINE; GP160 AB Antibodies that neutralize primary isolates of human immunodeficiency virus type 1 (HIV-1) appear during HIV-1 infection but are difficult to elicit by immunization with current vaccine products comprised of monomeric forms of HIV-1 envelope glycoprotein gp120. The limited neutralizing antibody response generated by gp120 vaccine products could be due to the absence or inaccessibility of the relevant epitopes. To determine whether neutralizing antibodies from HIV-1-infected patients bind to epitopes accessible on monomeric gp120 and/or oligomeric gp140 (ogp140), purified total immunoglobulin from the sera of two HIV-1-infected patients as well as pooled HIV immune globulin were selectively depleted of antibodies which bound to immobilized gp120 or ogpl40. After passage of each immunoglobulin preparation through the respective columns, antibody titers against gp120 and ogp140 were specifically reduced at least 128-fold. The gp120- and gp140-depleted antibody fraction from each serum displayed reduced neutralization activity against three primary and two T-cell line-adapted (TCLA) HIV-1 isolates. Significant residual neutralizing activity, however, persisted in the depleted sera, indicating additional neutralizing antibody specificities, gp120- and ogp140-specific antibodies eluted from each column neutralized both primary and TCLA viruses. These data demonstrate the presence and accessibility of epitopes on both monomeric gp120 and ogpl40 that are specific for antibodies that are capable of neutralizing primary isolates of HIV-1. Thus, the difficulties associated with eliciting neutralizing antibodies by using current monomeric gp120 subunit vaccines may be related less to improper protein structure and more to ineffective immunogen formulation and/or presentation. C1 Henry M Jackson Fdn, Rockville, MD 20850 USA. Walter Reed Army Inst Res, Div Retrovirol, Rockville, MD 20850 USA. USN, Med Res Inst, Dept Infect Dis, Bethesda, MD 20889 USA. Adv Biosci Labs, Kensington, MD 20895 USA. RP VanCott, TC (reprint author), Henry M Jackson Fdn, 13 Taft Ct,Suite 200, Rockville, MD 20850 USA. EM tvancott@hiv.hjf.org NR 80 TC 32 Z9 32 U1 3 U2 4 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0022-538X J9 J VIROL JI J. Virol. PD DEC PY 1998 VL 72 IS 12 BP 9656 EP 9667 PG 12 WC Virology SC Virology GA 137AW UT WOS:000076892100026 PM 9811699 ER PT J AU Frankel, SS Steinman, RM Michael, NL Kim, SR Bhardwaj, N Pope, M Louder, MK Ehrenberg, PK Parren, PWHI Burton, DR Katinger, H VanCott, TC Robb, ML Birx, DL Mascola, JR AF Frankel, SS Steinman, RM Michael, NL Kim, SR Bhardwaj, N Pope, M Louder, MK Ehrenberg, PK Parren, PWHI Burton, DR Katinger, H VanCott, TC Robb, ML Birx, DL Mascola, JR TI Neutralizing monoclonal antibodies block human immunodeficiency virus type 1 infection of dendritic cells and transmission to T cells SO JOURNAL OF VIROLOGY LA English DT Article ID PERIPHERAL-BLOOD; CHEMOKINE-CORECEPTORS; PRODUCTIVE INFECTION; LANGERHANS CELLS; RHESUS MACAQUES; HIV-1 ENTRY; REPLICATION; LYMPHOCYTES; EFFICIENT; MUCOSAL AB Prevention of the initial infection of mucosal dendritic cells (DC) and interruption of the subsequent transmission of HIV-1 from DC to T cells are likely to be important attributes of an effective human immunodeficiency virus type 1 (HIV-1) vaccine. While anti-HIV-l neutralizing antibodies have been difficult to elicit by immunization, there are several human monoclonal antibodies (MAbs) that effectively neutralize virus infection of activated T cells. We investigated the ability of three well-characterized neutralizing MAbs (IgG1b12, 2F5, and 2G12) to block HIV-1 infection of human DC. DC were generated from CD14(+) blood cells or obtained from cadaveric human skin. The MAbs prevented viral entry into purified DC and the ensuing productive infection in DC/T-cell cultures. When DC were first pulsed with HIV-1, MAbs blocked the subsequent transmission to unstimulated CD3(+) T cells. Thus, neutralizing antibodies can block HIV-1 infection of DC and the cell-to-cell transmission of virus from infected DC to T cells. These data suggest that neutralizing antibodies could interrupt the initial events associated with mucosal transmission and regional spread of HIV-1. C1 Walter Reed Army Inst Res, Div Retrovirol, Rockville, MD 20850 USA. Henry M Jackson Fdn Advancement Mil Med, Rockville, MD USA. USN, Med Res Inst, Dept Infect Dis, Bethesda, MD USA. Armed Forces Inst Pathol, Dept Infect & Parasit Dis Pathol, Amer Registry Pathol, Div AIDS & Emerging Infect Dis, Washington, DC 20306 USA. Rockefeller Univ, Cellular Physiol & Immunol Lab, New York, NY 10021 USA. Scripps Res Inst, Dept Immunol & Mol Biol, La Jolla, CA USA. Agr Univ Vienna, Inst Appl Microbiol, A-1180 Vienna, Austria. RP Frankel, SS (reprint author), Walter Reed Army Inst Res, Div Retrovirol, 13 Taft Court,Suite 200, Rockville, MD 20850 USA. RI Steinman, Ralph/F-7729-2012; OI Parren, Paul/0000-0002-4365-3859 FU NHLBI NIH HHS [HL59718]; NIAID NIH HHS [AI33292, AI40874, R01 AI033292, R01 AI040874, R37 AI033292] NR 47 TC 73 Z9 76 U1 1 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0022-538X J9 J VIROL JI J. Virol. PD DEC PY 1998 VL 72 IS 12 BP 9788 EP 9794 PG 7 WC Virology SC Virology GA 137AW UT WOS:000076892100041 PM 9811714 ER PT J AU Kelley, CA Coffin, RB Cifuentes, LA AF Kelley, CA Coffin, RB Cifuentes, LA TI Stable isotope evidence for alternative bacterial carbon sources in the Gulf of Mexico SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Article ID MISSISSIPPI RIVER PLUME; WEIGHT ORGANIC-MATTER; FRESH-WATER; INTERMEDIATE SALINITIES; ESTUARINE BACTERIA; CONTINENTAL-SLOPE; FRACTIONATION; MARINE; SURFACE; OCEAN C1 USN, Res Lab, Washington, DC 20375 USA. RP Kelley, CA (reprint author), Texas A&M Univ, Dept Oceanog, College Stn, TX 77843 USA. RI Kelley, Cheryl/K-9392-2015 NR 47 TC 45 Z9 46 U1 4 U2 11 PU AMER SOC LIMNOLOGY OCEANOGRAPHY PI WACO PA 5400 BOSQUE BLVD, STE 680, WACO, TX 76710-4446 USA SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD DEC PY 1998 VL 43 IS 8 BP 1962 EP 1969 PG 8 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 148YZ UT WOS:000077563500020 ER PT J AU Goyet, C Metzl, N Millero, F Eischeid, G O'Sullivan, D Poisson, A AF Goyet, C Metzl, N Millero, F Eischeid, G O'Sullivan, D Poisson, A TI Temporal variation of the sea surface CO2/carbonate properties in the Arabian Sea SO MARINE CHEMISTRY LA English DT Article DE Arabian Sea; total alkalinity; total carbon dioxide ID DISSOCIATION-CONSTANTS; CARBONIC-ACID; CO2; CHLOROPHYLL; SEAWATER; OCEAN AB As part of the U.S, JGOFS program in the Arabian Sea we have measured total CO2 (TCO2), and total alkalinity (TA) throughout the water column at selected station locations. In addition we measured the fugacity of CO2 in surface seawater and in the air above seawater along the cruise tracks. Between 10 degrees N and 20 degrees N, these measurements were repeated five times in January, March, July, November, and December 1995, and show different temporal variations of the carbonate properties in surface seawater depending upon the different regional hydrological and biological regimes. In order to estimate the relative importance of each process (physics, biology and thermodynamics) on the temporal carbon cycle in these regions, we use a 1-D process model initialized with the data from January 1995 and forced with climatological fields. The outputs of the model applied at three locations (10 degrees N 65 degrees E; 14.5 degrees N 65 degrees E; and 19 degrees N 65 degrees E) in the Arabian Sea are compared with US-JGOFS observations. The forcing terms and the 'standard' biological parameters reproduce the CO2 cycle at 10 degrees N and 14.5 degrees N. At 19 degrees N, the 'standard' biological activity has to be reduced by a factor two to approach the observed CO2 concentrations. The model outputs predict seasons of minimum and maximum fCO(2), in surface seawater at time periods where no data are available in October and May/June, respectively. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. Univ Paris 06, Phys & Chim Marines Lab, F-75252 Paris 05, France. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP Goyet, C (reprint author), Woods Hole Oceanog Inst, MS 25, Woods Hole, MA 02543 USA. OI O'Sullivan, Daniel/0000-0001-9104-5703 NR 32 TC 14 Z9 14 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-4203 J9 MAR CHEM JI Mar. Chem. PD DEC PY 1998 VL 63 IS 1-2 BP 69 EP 79 DI 10.1016/S0304-4203(98)00051-6 PG 11 WC Chemistry, Multidisciplinary; Oceanography SC Chemistry; Oceanography GA 214ZP UT WOS:000081357700006 ER PT J AU Mechtel, DM Charles, HK Francomacaro, AS AF Mechtel, DM Charles, HK Francomacaro, AS TI Laser-based electro-optic testing of multichip module structures SO MICROELECTRONICS RELIABILITY LA English DT Article AB Laser-based electro-optic probing is a proven noninvasive technique for testing high-speed microwave circuits on substrates such as gallium arsenide (GaAs) and indium phosphide (InP). We have extended this technique to probe circuit structures on doped and poled polyimide substrates that are useful in high-density packaging applications such as multichip modules (MCMs). Our results demonstrate the potential to improve the testability of MCMs by probing circuit structures that are buried in the central layers of an MCM. In addition to direct, point-by-point electric field measurements in representative MCM structures, we have investigated the poled polyimide dielectric efficacy both as a dielectric circuit layer and as a suitable electro-optic material. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN Acad, Annapolis, MD 21401 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. RP Mechtel, DM (reprint author), USN Acad, 105 Maryland Ave, Annapolis, MD 21401 USA. EM mechtel@nadn.navy.mil NR 9 TC 3 Z9 3 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0026-2714 J9 MICROELECTRON RELIAB JI Microelectron. Reliab. PD DEC PY 1998 VL 38 IS 12 BP 1847 EP 1853 DI 10.1016/S0026-2714(98)00189-9 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 154DP UT WOS:000077873600006 ER PT J AU Nissen, ME AF Nissen, ME TI Redesigning reengineering through measurement-driven inference SO MIS QUARTERLY LA English DT Article DE business process reengineering; expert systems; knowledge-based systems; metrics; process measurement; process redesign ID BUSINESS; AUTOMATION AB This first decade of business process reengineering (BPR) is blemished by sporadic success, pathological performance, and inefficiency. Reengineering inefficiency is driven in part by cost and cycle time for process redesign, a process itself that requires deep reengineering knowledge and specialized expertise. However, such knowledge and expertise are not addressed by extant, first-generation redesign tools, so these intellectual activities must be performed manually at present, or provided through expensive BPR consulting services. Knowledge-based systems (KBS) address the requirements for knowledge and expertise directly, and they can augment first-generation fools to reduce redesign cost and cycle time, and hence increase reengineering efficiency. This study employs the methods and tools of reengineering recursively, to redesign the process of process redesign itself. Using measurement-driven inference, a second-generation KBS redesign tool called KOPeR is developed to automate three key intellectual activities required for process redesign-process measurement, pathology diagnosis, and transformation matching. This KBS tool is used in the laboratory to redesign a commercial process from the reengineering literature and then employed in the field to redesign operational procurement processes in the context of an "industrial strength" reengineering project. The study finds that KOPeR-supported redesign enables new reengineering efficiencies in terms of direct automation effects and indirect knowledge effects. Results of this investigation highlight new opportunities available to the IS manager-such as improving the return on investment from BPR, enhancing the capability for knowledge management and organizational memory, and achieving competitive advantage through knowledge integration-opportunities that do not necessarily require KBS automation to seize. This investigation also lays a research cornerstone and foundation for development of process redesign theory and investigation of reengineering effectiveness. C1 USN, Postgrad Sch, Syst Management Dept, Monterey, CA 93943 USA. RP Nissen, ME (reprint author), USN, Postgrad Sch, Syst Management Dept, 555 Dyer Rd,Code SM-Ni, Monterey, CA 93943 USA. NR 53 TC 43 Z9 43 U1 1 U2 7 PU SOC INFORM MANAGE-MIS RES CENT PI MINNEAPOLIS PA UNIV MINNESOTA-SCH MANAGEMENT 271 19TH AVE SOUTH, MINNEAPOLIS, MN 55455 USA SN 0276-7783 J9 MIS QUART JI MIS Q. PD DEC PY 1998 VL 22 IS 4 BP 509 EP 534 DI 10.2307/249553 PG 26 WC Computer Science, Information Systems; Information Science & Library Science; Management SC Computer Science; Information Science & Library Science; Business & Economics GA 174HF UT WOS:000079028100005 ER PT J AU Zdziarski, AA Poutanen, J Mikolajewska, J Gierlinski, M Ebisawa, K Johnson, WN AF Zdziarski, AA Poutanen, J Mikolajewska, J Gierlinski, M Ebisawa, K Johnson, WN TI Broad-band X-ray/gamma-ray spectra and binary parameters of GX 339-4 and their astrophysical implications SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Review DE accretion, accretion discs; binaries : general; stars : individual : GX 339-4; gamma-rays : observations; gamma-rays : theory; X-rays : stars ID ACTIVE GALACTIC NUCLEI; RELATIVISTIC THERMAL PLASMAS; BLACK-HOLE CANDIDATES; ACCRETION DISKS; CYGNUS X-1; NEUTRON-STARS; THIN CLOUDS; OPTICAL OBSERVATIONS; CENTRAL REGIONS; COLD MATTER AB We present X-ray/gamma-ray spectra of the binary GX 339-4 observed in the hard state simultaneously by Ginga and CGRO OSSE during an outburst in 1991 September. The Ginga X-ray spectra are well represented by a power law with a photon spectral index of Gamma similar or equal to 1.75 and a Compton reflection component with a fluorescent Fe K alpha line corresponding to a solid angle of an optically thick, ionized medium of similar to 0.3 x 2 pi. The OSSE data (greater than or equal to 50 keV) require a sharp high-energy cut-off in the power-law spectrum. The broad-band spectra are very well modelled by repeated Compton scattering in a thermal plasma with an optical depth of tau similar to 1 and kT similar or equal to 50 keV. We also study the distance to the system and find it to be 23 kpc, ruling out earlier determinations of similar to 1 kpc. Using this limit, the observed reddening and the orbital period, we find the allowed range of the mass of the primary is consistent with it being a black hole. We find the data are inconsistent with models of either homogenous or patchy coronae above the surface of an accretion disc. Rather, they are consistent with the presence of an inner hot disc with the viscosity parameter of alpha - 1 accreting at a rate close to the maximum set by advection. The hot disc is surrounded by a cold outer disc, which gives rise to the reflection component and a soft X-ray excess, also present in the data. The seed photons for Comptonization are unlikely to be due to thermal synchrotron radiation. Rather, they are supplied by the outer cold disc and/or cold clouds within the hot disc. e(+/-) pair production is negligible if electrons are thermal. The hot disc model, fur which scaled parameters are independent of the black hole mass, is supported by the similarity of the spectrum of GX 339-4 to those of other black hole binaries and Seyfert is. On the other hand, their spectra in the soft gamma-ray regime are significantly harder than those of weakly magnetized neutron stars. Based on this difference, we propose that the presence of broad-band spectra corresponding to thermal Comptonization with kT greater than or similar to 50 keV represents a black hole signature. C1 N Copernicus Astron Ctr, PL-00716 Warsaw, Poland. Stockholm Observ, S-13336 Saltsjobaden, Sweden. Jagiellonian Univ, Astron Observ, PL-30244 Krakow, Poland. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Zdziarski, AA (reprint author), N Copernicus Astron Ctr, Bartycka 18, PL-00716 Warsaw, Poland. EM aaz@camk.edu.pl RI Johnson, Neil/G-3309-2014; Poutanen, Juri/H-6651-2016; OI Poutanen, Juri/0000-0002-0983-0049; Gierlinski, Marek/0000-0001-9149-3514 NR 123 TC 136 Z9 136 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD DEC 1 PY 1998 VL 301 IS 2 BP 435 EP 450 DI 10.1046/j.1365-8711.1998.02021.x PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 156AA UT WOS:000077978200018 ER PT J AU Hoffman, SL Rogers, WO Carucci, DJ Venter, JC AF Hoffman, SL Rogers, WO Carucci, DJ Venter, JC TI From genomics to vaccines: Malaria as a model system SO NATURE MEDICINE LA English DT Editorial Material ID PLASMODIUM C1 USN, Med Res Ctr, Malaria Program, Rockville, MD 20852 USA. Celera Genom Inc, Rockville, MD 20850 USA. Inst Genom Res, Rockville, MD 20850 USA. RP Hoffman, SL (reprint author), USN, Med Res Ctr, Malaria Program, 12300 Washington Ave, Rockville, MD 20852 USA. NR 12 TC 55 Z9 56 U1 0 U2 1 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1078-8956 J9 NAT MED JI Nat. Med. PD DEC PY 1998 VL 4 IS 12 BP 1351 EP 1353 DI 10.1038/3934 PG 3 WC Biochemistry & Molecular Biology; Cell Biology; Medicine, Research & Experimental SC Biochemistry & Molecular Biology; Cell Biology; Research & Experimental Medicine GA 144VW UT WOS:000077336900020 PM 9846563 ER PT J AU Mousseau, O Ferlet-Cavrois, V Campbell, AB Knudson, AR Buchner, S Fischer, B Schlogl, M AF Mousseau, O Ferlet-Cavrois, V Campbell, AB Knudson, AR Buchner, S Fischer, B Schlogl, M TI Application of an ion microbeam to determine the radial carrier density in an ion track SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 4th International Symposium on Swift Heavy Ions in Matter (SHIM98) CY MAY 11-15, 1998 CL BERLIN, GERMANY SP Commissariat Energie Atom (CEA/DSM/DRECAM), Deutsch Forsch Gemeinschaft (DFG), Wilhelm Heinrich Heraeus & Else Heraeus-Stiftung, Hahn-Meitner-Inst GmbH, Rontec GmbH, Varian GmbH ID COLLECTION AB The radial distribution of free carrier density generated in a single ion track is inferred from experimental results using an silicon microstrip-like detector array irradiated with an ion microbeam. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. CEA, Bruyeres Le Chatel, France. SFA, Landover, MD USA. GSI, Darmstadt, Germany. RP Campbell, AB (reprint author), USN, Res Lab, Code 6613,4555 Overlook Ave, Washington, DC 20375 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD DEC PY 1998 VL 146 IS 1-4 BP 607 EP 612 DI 10.1016/S0168-583X(98)00455-8 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 151KN UT WOS:000077719400094 ER PT J AU Nagem, RJ Sandri, G Lee, D AF Nagem, RJ Sandri, G Lee, D TI Parabolic equations for inhomogeneous elasticity SO NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA B-GENERAL PHYSICS RELATIVITY ASTRONOMY AND MATHEMATICAL PHYSICS AND METHODS LA English DT Article ID WAVE-PROPAGATION; SOLIDS; MEDIA; MODEL AB A set of parabolic equations is derived for time-harmonic wave propagation in an inhomogeneous elastic medium. The formulation is three-dimensional, and is written explicitly in Cartesian coordinates. Arbitrary spatial variations in density and in elastic parameters are considered. The parabolic equations are similar to previous equations used in computational ocean acoustics, and thus previously developed efficient numerical techniques may be applied directly to the elastic equations derived here. C1 Boston Univ, Dept Aeronaut & Mech Engn, Boston, MA 02215 USA. USN, Ctr Underwater Syst, Newport, RI 02841 USA. RP Nagem, RJ (reprint author), Boston Univ, Dept Aeronaut & Mech Engn, Boston, MA 02215 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU EDITRICE COMPOSITORI BOLOGNA PI BOLOGNA PA VIA STALINGRADO 97/2, I-40128 BOLOGNA, ITALY SN 0369-3554 J9 NUOVO CIMENTO B JI Nouvo Cimento Soc. Ital. Fis. B-Gen. Phys. Relativ. Astron. Math. Phys. Methods PD DEC PY 1998 VL 113 IS 12 BP 1503 EP 1508 PG 6 WC Physics, Multidisciplinary SC Physics GA 164TZ UT WOS:000078480800008 ER PT J AU Hrezo, RJ AF Hrezo, RJ TI Hypnosis: An alternative in pain management for nurse practitioners SO NURSE PRACTITIONER FORUM-CURRENT TOPICS AND COMMUNICATIONS LA English DT Article AB Hypnosis and the trance phenomenon is an age-old tool for the treatment of a variety of conditions, including pain. Medically accepted for over 50 years as a legitimate therapy, research continues into its mechanisms and actions. In this article, its origins, history, theoretical basis, and various uses are discussed. Case presentations from the author are provided, showing its use for a variety of pain management scenarios. Sample hypnotic scripts allow the reader to better visualize the applicability of hypnotic suggestion to general inductions and pain management. References are provided for individuals seeking further information and/or training in hypnosis. Copyright (C) 1998 by W.B. Saunders Company. C1 USN, Med Ctr, Navy Nurse Corps Anesthesia Program, Naval Sch Hlth Sci, San Diego, CA 92134 USA. RP Hrezo, RJ (reprint author), USN, Med Ctr, Navy Nurse Corps Anesthesia Program, Naval Sch Hlth Sci, San Diego, CA 92134 USA. NR 7 TC 3 Z9 3 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 1045-5485 J9 NURS PRACT FORUM JI Nurse Pract. Forum-Curr. Top. Commun. PD DEC PY 1998 VL 9 IS 4 BP 217 EP 226 PG 10 WC Nursing SC Nursing GA 144VD UT WOS:000077335200005 PM 10214224 ER PT J AU Frankel, MY Matthews, PJ Esman, RD Goldberg, L AF Frankel, MY Matthews, PJ Esman, RD Goldberg, L TI Practical optical beamforming networks SO OPTICAL AND QUANTUM ELECTRONICS LA English DT Article ID PHASED-ARRAY ANTENNA; TIME-STEERED ARRAY; FIBEROPTIC CONTROL; PROCESSOR; TRANSMITTER; SYSTEM AB A review of optical beamforming techniques is presented. The techniques are subdivided into two broad categories. First, several representative implementations of narrow band, phase-only techniques are summarized. A detailed description of a narrow band architecture realized in our laboratory is presented. The architecture is based on coherent heterodyning of two narrow linewidth Nd:YAG lasers, with a controlled angular beam offset to generate the required microwave phase progression. Second, several representative wideband, true time delay architectures are briefly described. A description of a 'dispersive-prism' based true time-delay technique developed in our laboratory is presented. The results show multi-octave one-dimensional transmit and receive true time-delay beamformer operation, as well as two-dimensional transmit beamformer operation. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Frankel, MY (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 28 TC 16 Z9 16 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0306-8919 J9 OPT QUANT ELECTRON JI Opt. Quantum Electron. PD DEC PY 1998 VL 30 IS 11-12 BP 1033 EP 1050 DI 10.1023/A:1006950928457 PG 18 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA 164VX UT WOS:000078485200008 ER PT J AU Shick, PC Brannon, RB AF Shick, PC Brannon, RB TI Oncocytoid artifact of the parotid gland - A newly reported artifact SO ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY ORAL RADIOLOGY AND ENDODONTICS LA English DT Article ID BIOPSY SPECIMENS; SALIVARY-GLANDS; LASER AB Electrocautery can induce significant alterations in the connective tissues and epithelium of specimens removed for diagnostic or therapeutic purposes. When electrocautery is used during parotid surgery, it can cause an oncocytoid artifact. The alterations described in this article are enlarged, tightly packed serous acinar cells with coarse to granular eosinophilic cytoplasm, distinct cell borders, and round basal nuclei that on cursory microscopic examination resemble oncocytes with respect to morphology. These changes are seen in conjunction with other, more recognized changes secondary to electrocautery and are believed to occur as a consequence of the electrothermal discharge. On the basis of our findings, this artifact is common in parotid surgical specimens and was misdiagnosed as benign oncocytic lesions in 5 cases. C1 USN, Med Ctr, Lab EDA 13, San Diego, CA 92134 USA. Louisiana State Univ, Sch Dent, Oral & Maxillofacial Pathol Dept, New Orleans, LA 70119 USA. RP Shick, PC (reprint author), USN, Med Ctr, Lab EDA 13, Suite 305,34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 19 TC 1 Z9 1 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 1079-2104 J9 ORAL SURG ORAL MED O JI Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod. PD DEC PY 1998 VL 86 IS 6 BP 720 EP 722 DI 10.1016/S1079-2104(98)90210-4 PG 3 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 147WP UT WOS:000077520700020 PM 9868731 ER PT J AU Hoang, JT Foss, RD Nowacki, MR Kelly, KE AF Hoang, JT Foss, RD Nowacki, MR Kelly, KE TI Basaloid squamous cell carcinoma and fine-needle aspiration: A potential diagnostic pitfall SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT 99th Annual Meeting of the American-Academy-of-Otolaryngology-Head-and-Neck-Surgery CY SEP 16-22, 1995 CL NEW ORLEANS, LOUISIANA SP Amer Acad Otolaryngol Head & Neck Surg ID HEAD; NECK; HYPOPHARYNX C1 USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, San Diego, CA 92134 USA. USN, Med Ctr, Dept Pathol, San Diego, CA 92134 USA. RP Foss, RD (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 10 TC 5 Z9 5 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD DEC PY 1998 VL 119 IS 6 BP 655 EP 657 DI 10.1016/S0194-5998(98)70029-4 PG 3 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA 146CE UT WOS:000077409400019 PM 9852543 ER PT J AU Marchette, DJ Solka, JL Guidry, R Green, J AF Marchette, DJ Solka, JL Guidry, R Green, J TI The advanced distributed region of interest tool SO PATTERN RECOGNITION LA English DT Article ID ADAPTIVE MIXTURES; DIMENSION AB This paper details recent work on the use of low-level features for the identification of regions of interest in images. Using-low-level features, the system classifies regions in the image via probability densities estimates for each class. These densities are estimated semi-parametrically, giving the system great flexibility in the functional form of the densities. This paper details the environment designed to allow easy implementation of pattern recognition algorithms. (C) 1998 Pattern Recognition Society. Published by Elsevier Science Ltd. All rights reserved. C1 USN, Ctr Surface Warfare, Dahlgren Div, Adv Computat Technol Grp,Code B10, Dahlgren, VA 22448 USA. USN, Ctr Surface Warfare, Dahlgren Div, Space Syst Applicat Branch,Code T12, Dahlgren, VA 22448 USA. RP USN, Ctr Surface Warfare, Dahlgren Div, Adv Computat Technol Grp,Code B10, 17320 Dahlgren RD, Dahlgren, VA 22448 USA. EM dmarche@nswc.navy.mil NR 22 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 0031-3203 EI 1873-5142 J9 PATTERN RECOGN JI Pattern Recognit. PD DEC PY 1998 VL 31 IS 12 BP 2103 EP 2118 DI 10.1016/S0031-3203(98)00025-9 PG 16 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 132UM UT WOS:000076648700024 ER PT J AU Wheeler, DS Vazquez, WD Vaux, KK Poss, WB AF Wheeler, DS Vazquez, WD Vaux, KK Poss, WB TI Streptococcal pyomyositis: Case report and review SO PEDIATRIC EMERGENCY CARE LA English DT Article DE streptococcal pyomyositis; GABHS ID VARICELLA AB Pyomyositis is most often associated with Staphylococcus aureus infections after trauma. We describe an unusual presentation of pyomyositis of the chest wall secondary to group A betahemolytic streptococcus infection in a 15-month-old child with acute abdominal symptoms. in addition, the patient had no history or evidence of trauma to the affected area. Pyomyositis presenting in this manner secondary to group A beta-hemolytic streptococcus infection in the absence of a primary varicella infection has not been previously reported. C1 USN, Med Ctr, Clin Invest Dept, San Diego, CA 92134 USA. USN, Med Ctr, Dept Pediat, San Diego, CA 92134 USA. USN, Med Ctr, Dept Surg, Div Pediat Surg, San Diego, CA 92134 USA. RP Poss, WB (reprint author), USN, Med Ctr, Clin Invest Dept, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 13 TC 8 Z9 8 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0749-5161 J9 PEDIATR EMERG CARE JI Pediatr. Emerg. Care PD DEC PY 1998 VL 14 IS 6 BP 411 EP 412 DI 10.1097/00006565-199812000-00009 PG 2 WC Emergency Medicine; Pediatrics SC Emergency Medicine; Pediatrics GA 152PN UT WOS:000077786100009 PM 9881987 ER PT J AU Ngai, KL AF Ngai, KL TI Correlation between the secondary beta-relaxation time at T-g and the Kohlrausch exponent of the primary alpha-relaxation SO PHYSICA A LA English DT Article; Proceedings Paper CT Collective Phenomena in Physics Meeting on Dynamkcs and Kinetics of Fluids and Materials (CPiP 98) CY JAN 07-10, 1998 CL UNIV WEST INDIES, CAVE HILL, BRIDGETOWN, BARBADOS HO UNIV WEST INDIES, CAVE HILL ID MOLECULAR-DYNAMICS SIMULATION; GLASS-FORMING LIQUIDS; BAND DIELECTRIC-SPECTROSCOPY; NUCLEAR-MAGNETIC-RESONANCE; BULK AMORPHOUS POLYMERS; CRYSTALLINE POLYMERS; SUPERCOOLED LIQUIDS; COUPLING MODEL; POLY(CYCLOHEXYL METHACRYLATE); NEUTRON-SCATTERING AB A correlation between the logarithm of the secondary beta-relaxation time, log[tau(beta)(T-g)], and the Kohlrausch exponent, (1 - n), of the primary alpha-relaxation correlation function exp[-(t/tau(alpha))(1-n)] has been found in glass-forming materials in general. I was guided to this finding by the coupling model based on the similarity of some secondary beta-relaxation to the primitive alpha-relaxation of the model. The logarithm of the primitive alpha-relaxation time at T-g, log[tau(0)(T-g)], calculated according to the coupling model from the observed alpha-relaxation at T-g, is exactly correlated with the Kohlrausch exponent. A similar, although inexact, correlation between log[tau(beta)(T-g)] and (1-n) is thus expected and found. Furthermore, the experimental values of tau(beta)(T-g) are remarkably close in order of magnitude to tau(0)(T-g) for many glass-formers as anticipated. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ngai, KL (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM Ngai@estd.nrl.navy.mil NR 105 TC 22 Z9 22 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD DEC 1 PY 1998 VL 261 IS 1-2 BP 36 EP 50 DI 10.1016/S0378-4371(98)00374-4 PG 15 WC Physics, Multidisciplinary SC Physics GA 149HA UT WOS:000077598000005 ER PT J AU Santangelo, PG Roland, CM AF Santangelo, PG Roland, CM TI Test of the energy landscape interpretation of fragility in polymers SO PHYSICAL REVIEW B LA English DT Article ID SEGMENTAL RELAXATION; POLYISOPRENE; DYNAMICS; NETWORKS; LIQUIDS; MOTION AB Variation of the number of crosslinks in polyvinylethylene (PVE) networks has a marked effect on the T-g-normalized temperature dependence ('"fragility") of the segmental relaxation times, even though the local chemical environment of virtually all repeat units is unchanged. Since the heat-capacity increment at T-g is a decreasing function of the number of crosslinks, there is an inverse correlation between fragility and the heat-capacity difference between PVE's glassy and liquid states; This result is opposite to expectations based on an energy landscape interpretation of fragility. [S0163-1829(98)00245-8]. C1 USN, Res Lab, Div Chem, Code 6120, Washington, DC 20375 USA. RP Santangelo, PG (reprint author), USN, Res Lab, Div Chem, Code 6120, Washington, DC 20375 USA. NR 23 TC 24 Z9 24 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD DEC 1 PY 1998 VL 58 IS 21 BP 14121 EP 14123 DI 10.1103/PhysRevB.58.14121 PG 3 WC Physics, Condensed Matter SC Physics GA 144RC UT WOS:000077328000009 ER PT J AU Skelton, EF Hagans, PL Qadri, SB Dominguez, DD Ehrlich, AC Hu, JZ AF Skelton, EF Hagans, PL Qadri, SB Dominguez, DD Ehrlich, AC Hu, JZ TI In situ monitoring of crystallographic changes in Pd induced by diffusion of D SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-DIFFRACTION AB Crystallographic changes in a palladium wire cathode were monitored in situ, as deuterium was electrochemically deposited on the surface and diffused radially into the wire. Initially, the win was pure Pd. A constant electrolysis current density of 1 mA/cm(2) was maintained and D slowly diffused into the wire. As the D concentration increased, the wire transformed from pure Pd, to the alpha phase, and finally into the beta phase. This reversible phase transformation begins on the surface and progresses radially inward. During the experiment, x-ray-diffraction data were collected from a volume element of about 180 pi. This volume element was systematically moved in 50-mu m steps from the edge to the center of a 1.0 mm diameter Pd wire. Throughout the course of the experiment, the bulk value of x in PdDx, as determined from simultaneous measurements of the electrical resistivity, increased from 0 to similar to 0.72. For each setting of the volume element, a monotonic increase in the volume of the a phase was observed, until the material entered the two-phase region. Once the beta phase appeared, the volumes of both phases decreased slightly with continued loading. The integrated intensities of diffraction peaks from each phase were used in conjunction with the known phase diagram to estimate the rate of compositional change within the volume element. The diffusion rate for the solute atoms was estimated to be 57 +/- 8 nm/s, based on the temporal and spatial dependence of the integrated intensities of the diffraction peaks from each phase. These data also were used to evaluate the time dependence of the concentration of the solute atoms partial derivative c/partial derivative t and their diffusivity D. The value of partial derivative c/partial derivative t increased linearly from 6.2x 10(-5) s(-1) at the surface, to 7.6X10(-5) s(-1) midway into the wire. D was computed to be (3.1+/-1.0) x10(-11) m(2)/s when the transition began at r=250 mu m; 2 ks later it had decreased to (2.1+/-0.3) x 10(-11) m(2)/s. This may be due to the fact that the volume of the beta lattice also decreased during this period. [S0163-1829(98)01846-3]. C1 USN, Res Lab, Div Condensed Matter & Radiat Sci, Washington, DC 20375 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. Carnegie Inst Washington, Geophys Lab, Washington, DC 20015 USA. Carnegie Inst Washington, Ctr High Pressure Res, Washington, DC 20015 USA. RP Skelton, EF (reprint author), USN, Res Lab, Div Condensed Matter & Radiat Sci, Washington, DC 20375 USA. NR 14 TC 5 Z9 5 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD DEC 1 PY 1998 VL 58 IS 22 BP 14775 EP 14779 DI 10.1103/PhysRevB.58.14775 PG 5 WC Physics, Condensed Matter SC Physics GA 146XW UT WOS:000077460000030 ER PT J AU Abe, K Akagi, T Anthony, PL Antonov, R Arnold, RG Averett, T Band, HR Bauer, JM Borel, H Bosted, PE Breton, V Button-Shafer, J Chen, JP Chupp, TE Clendenin, J Comptour, C Coulter, KP Court, G Crabb, D Daoudi, M Day, D Dietrich, FS Dunne, J Dutz, H Erbacher, R Fellbaum, J Feltham, A Fonvieille, H Frlez, E Garvey, D Gearhart, R Gomez, J Grenier, P Griffioen, KA Hoibraten, S Hughes, EW Hyde-Wright, C Johnson, JR Kawall, D Klein, A Kuhn, SE Kuriki, M Lindgren, R Liu, TJ Lombard-Nelsen, RM Marroncle, J Maruyama, T Maruyama, XK McCarthy, J Meyer, W Meziani, ZE Minehart, R Mitchell, J Morgenstern, J Petratos, GG Pitthan, R Pocanic, D Prescott, C Prepost, R Raines, P Raue, B Reyna, D Rijllart, A Roblin, Y Rochester, LS Rock, SE Rondon, OA Sick, I Smith, LC Smith, TB Spengos, M Staley, F Steiner, P St Lorant, S Stuart, LM Suekane, F Szalata, ZM Tang, H Terrien, Y Usher, T Walz, D Wesselmann, F White, JL Witte, K Young, CC Youngman, B Yuta, H Zapalac, G Zihlmann, B Zimmermann, D AF Abe, K Akagi, T Anthony, PL Antonov, R Arnold, RG Averett, T Band, HR Bauer, JM Borel, H Bosted, PE Breton, V Button-Shafer, J Chen, JP Chupp, TE Clendenin, J Comptour, C Coulter, KP Court, G Crabb, D Daoudi, M Day, D Dietrich, FS Dunne, J Dutz, H Erbacher, R Fellbaum, J Feltham, A Fonvieille, H Frlez, E Garvey, D Gearhart, R Gomez, J Grenier, P Griffioen, KA Hoibraten, S Hughes, EW Hyde-Wright, C Johnson, JR Kawall, D Klein, A Kuhn, SE Kuriki, M Lindgren, R Liu, TJ Lombard-Nelsen, RM Marroncle, J Maruyama, T Maruyama, XK McCarthy, J Meyer, W Meziani, ZE Minehart, R Mitchell, J Morgenstern, J Petratos, GG Pitthan, R Pocanic, D Prescott, C Prepost, R Raines, P Raue, B Reyna, D Rijllart, A Roblin, Y Rochester, LS Rock, SE Rondon, OA Sick, I Smith, LC Smith, TB Spengos, M Staley, F Steiner, P St Lorant, S Stuart, LM Suekane, F Szalata, ZM Tang, H Terrien, Y Usher, T Walz, D Wesselmann, F White, JL Witte, K Young, CC Youngman, B Yuta, H Zapalac, G Zihlmann, B Zimmermann, D TI Measurements of the proton and deuteron spin structure functions g(1) and g(2) SO PHYSICAL REVIEW D LA English DT Review ID DEEP-INELASTIC-SCATTERING; BJORKEN SUM-RULE; POLARIZED STRUCTURE FUNCTIONS; HYPERON SEMILEPTONIC DECAYS; NUCLEON STRUCTURE FUNCTIONS; SMALL-X-BEHAVIOR; ENERGY ELECTRON-BEAMS; MAGNETIC FORM-FACTORS; RESONANCE REGION; PARTON-MODEL AB Measurements are reported of the proton and deuteron spin structure functions g(1)(p) and g(1)(d) at beam energies of 29.1, 16.2., and 9.7 GeV, and g(2)(p) and g(2)(d) at a beam energy of 29.1 GeV. The integrals Gamma(p) = integral(0)(1)g(1)(p)(x, Q(2))dx and Gamma(d) = integral(0)(1)g(1)(d)(x, Q(2))dx were evaluated at fixed Q(2) = 3 (GeV/c)(2) using the full data set to yield Gamma(p) = 0.132+/-0.003(stat)+/-0.009(syst) and Gamma(d)=0.047+/-0.003+/-0.006. The Q(2) dependence of the ratio g(1)/F-1 was studied and found to be small for Q(2) > 1 (GeV/c)(2). Within experimental precision the g(2) data are well described by the twist-2 contribution, g(2)(WW). Twist-3 matrix elements were extracted and compared to theoretical predictions. The asymmetry A(2) was measured and found to be significantly smaller than the positivity limit root R for both proton and deuteron targets. A(2)(p) is found to be positive and inconsistent with zero. Measurements of g(1) in the resonance region show strong variations with x and Q2, consistent with resonant amplitudes extracted from unpolarized data. These data allow us to study the Q(2) dependence of the integrals Gamma(p) and Gamma(n) below the scaling region. [S0556-2821(98)06919-7]. C1 Tohoku Univ, Sendai, Miyagi 980, Japan. American Univ, Washington, DC 20016 USA. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. Univ Blaise Pascal, CNRS, IN2P3, LPC, F-63170 Aubiere, France. Ctr Etud Saclay, Serv Phys Nucl, DAPNIA, F-91191 Gif Sur Yvette, France. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Massachusetts, Amherst, MA 01003 USA. Univ Michigan, Ann Arbor, MI 48109 USA. USN, Postgrad Sch, Monterey, CA 93943 USA. Old Dominion Univ, Norfolk, VA 23529 USA. Univ Penn, Philadelphia, PA 19104 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Stanford, CA 94305 USA. Temple Univ, Philadelphia, PA 19122 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Univ Virginia, Charlottesville, VA 22901 USA. Coll William & Mary, Williamsburg, VA 23187 USA. Univ Wisconsin, Madison, WI 53706 USA. Univ Liverpool, Oliver Lodge Lab, Liverpool L69 3BX, Merseyside, England. Univ Bonn, D-53113 Bonn, Germany. FFIYM, N-2007 Kjeller, Norway. Kent State Univ, Kent, OH 44242 USA. Florida Int Univ, Miami, FL 33199 USA. CERN, CH-1211 Geneva 23, Switzerland. RP Abe, K (reprint author), Tohoku Univ, Sendai, Miyagi 980, Japan. RI Averett, Todd/A-2969-2011; Rondon Aramayo, Oscar/B-5880-2013; Frlez, Emil/B-6487-2013; Day, Donal/C-5020-2015 OI Day, Donal/0000-0001-7126-8934 NR 186 TC 192 Z9 192 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 1 PY 1998 VL 58 IS 11 AR 112003 PG 54 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 145NB UT WOS:000077376800010 ER PT J AU Tran, P AF Tran, P TI Solving the time-dependent Schrodinger equation: Suppression of reflection from the grid boundary with a filtered split-operator approach SO PHYSICAL REVIEW E LA English DT Article AB We present the split-operator approach, with an additional filtering step, for solving the time-dependent Schrodinger equation that significantly suppresses the backreflection of waves from the grid boundaries. [S1063-651X(98)01712-7]. C1 USN, Air Warfare Ctr, Weapons Div, Res & Technol Grp, China Lake, CA 93555 USA. RP Tran, P (reprint author), USN, Air Warfare Ctr, Weapons Div, Res & Technol Grp, Code 4B4000D, China Lake, CA 93555 USA. NR 3 TC 10 Z9 10 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD DEC PY 1998 VL 58 IS 6 BP 8049 EP 8051 DI 10.1103/PhysRevE.58.8049 PN B PG 3 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 148PW UT WOS:000077541900083 ER PT J AU Hazak, G Velikovich, AL Gardner, JH Dahlburg, JP AF Hazak, G Velikovich, AL Gardner, JH Dahlburg, JP TI Shock propagation in a low-density foam filled with fluid SO PHYSICS OF PLASMAS LA English DT Article AB It is found that when a planar shock is imparted to a system of a foam of low mean density filled with fluid (fiber density > ambient fluid density), an undercompressed quasisteady post-shock state is established. In this state, pressure and density are lower than the values predicted by Hugoniot relations for a uniform fluid with the same average fluid-foam density. It is shown that this undercompression phenomenon is due to residual correlations of fluctuations left after the saturation of the initially rapid mixing of fiber material with the background fluid. Generalized Hugoniot relations are derived for quasiplanar shocks in nonuniform systems, with foam as an example. The behavior of fluctuations in such systems is studied. Formulas for the level of fluctuations induced by a shock as it propagates through foam and for the relaxation time of the fluctuations, are derived. (C) 1998 American Institute of Physics. [S1070-664X(98)03412-0]. C1 Berkeley Res Associates Inc, Springfield, VA 22150 USA. USN, Res Lab, LCP&FD, Washington, DC 20375 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Nucl Res Ctr Negev, Dept Phys, IL-84190 Beer Sheva, Israel. RP Hazak, G (reprint author), Berkeley Res Associates Inc, Springfield, VA 22150 USA. RI Velikovich, Alexander/B-1113-2009 NR 14 TC 26 Z9 27 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD DEC PY 1998 VL 5 IS 12 BP 4357 EP 4365 DI 10.1063/1.873172 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 139LX UT WOS:000077031000031 ER PT J AU Penano, JR Ganguli, G Amatucci, WE Walker, DN Gavrishchaka, V AF Penano, JR Ganguli, G Amatucci, WE Walker, DN Gavrishchaka, V TI Velocity shear-driven instabilities in a rotating plasma layer SO PHYSICS OF PLASMAS LA English DT Article ID STABILITY; FLOW AB The linear stability of a radially localized layer rotating about the cylindrical axis in a magnetized plasma is investigated using an eigenvalue analysis. The eigenvalue equation is solved numerically in a parameter regime characteristic of the Space Physics Simulation Chamber (SPSC) experiments [Amatucci et al., Phys. Rev. Lett. 77, 1978 (1996)] at the Naval Research Laboratory (NRL). Four types of instabilities are predicted. They are type-A and type-B Kelvin-Helmholtz instabilities, a transverse current-driven instability, and the inhomogeneous energy density driven instability (IEDDI). A quantitative comparison between theory and experiment indicates that an experimentally observed fluctuation in a rotating plasma layer is an IEDDI. (C) 1998 American Institute of Physics. [S1070-664X(98)01912-0]. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. RP Penano, JR (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 22 TC 18 Z9 18 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD DEC PY 1998 VL 5 IS 12 BP 4377 EP 4383 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 139LX UT WOS:000077031000034 ER PT J AU Apruzese, JP Pulsifer, PE Davis, J Clark, RW Whitney, KG Thornhill, JW Sanford, TWL Chandler, GA Deeney, C Fehl, DL Nash, TJ Spielman, RB Stygar, WA Struve, KW Mock, RC Gilliland, TL Jobe, DO McGurn, JS Seamen, JF Torres, JA Vargas, M AF Apruzese, JP Pulsifer, PE Davis, J Clark, RW Whitney, KG Thornhill, JW Sanford, TWL Chandler, GA Deeney, C Fehl, DL Nash, TJ Spielman, RB Stygar, WA Struve, KW Mock, RC Gilliland, TL Jobe, DO McGurn, JS Seamen, JF Torres, JA Vargas, M TI K-shell radiation physics in the ultrahigh optical depth pinches of the Z generator SO PHYSICS OF PLASMAS LA English DT Article ID X-RAY-EMISSION; ALUMINUM-WIRE-ARRAY; SIMILAR ATOMIC NUMBERS; HIGH-POWER; PLASMAS; IMPLOSIONS; OPTIMIZATION; TEMPERATURE; DIAGNOSTICS; ELEMENTS AB Al: Mg alloy wire arrays of mass loads 1.3-3.6 mg/cm have been imploded with peak currents of 19 MA on the 60 TW Z generator [R. B. Spielman et al., Phys. Plasmas 5, 2105 (1998)] at Sandia National Laboratories. The large mass loads have resulted in the highest K-shell x-ray line optical depths (similar to 10(3)) produced to date in Z-pinches. Analysis of the time-resolved spectrum of a 2.1 mg/cm shot near the time of peak compression has yielded a temperature-density profile of the pinch that approximately reproduces all features of the x-ray data except the continuum above 5 keV, which is underpredicted. The Ly alpha/He for Al is shown to be enhanced relative to that alpha ratio of Mg by two mechanisms: photopumped ladder ionization and absorption of the Al He-like line in a cool outer halo. This analysis and comparisons to some Ti shots demonstrates that the K-shell yield of Al is significantly reduced by line and continuum self-absorption, but that of Ti is not. (C) 1998 American Institute of Physics. [S1070-664X(98)05012-5]. C1 USN, Res Lab, Div Plasma Phys, Radiat Hydrodynam Branch, Washington, DC 20375 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Apruzese, JP (reprint author), USN, Res Lab, Div Plasma Phys, Radiat Hydrodynam Branch, Washington, DC 20375 USA. NR 31 TC 36 Z9 37 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD DEC PY 1998 VL 5 IS 12 BP 4476 EP 4483 DI 10.1063/1.873185 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 139LX UT WOS:000077031000045 ER PT J AU Zonca, F Chen, L Santoro, RA Dong, JQ AF Zonca, F Chen, L Santoro, RA Dong, JQ TI Existence of discrete modes in an unstable shear Alfven continuous SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Letter ID KINETIC BALLOONING MODES; MAGNETOHYDRODYNAMIC MODES; ENERGETIC PARTICLES; TOKAMAKS; EQUATIONS; RESONANCE; WAVE AB In this letter, we demonstrate the existence of unstable ion temperature gradient driven Alfven eigenmodes in tokamak plasmas, which are ideally stable with respect to magnetohydrodynamics (MHD). Conditions for the destabilization of such modes are quantitatively discussed on the basis of theoretical analyses of the mode dispersion relation, which is given in a compact analytical form. It is emphasized that instability requires both sufficiently strong thermal ion temperature gradients and that the plasma be sufficiently close to ideal MHD marginal stability. C1 Assoc EURATOM ENEA Fus, I-00044 Frascati, Italy. Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92717 USA. USN, Res Lab, Washington, DC 20375 USA. SW Inst Phys, Chengdu, Peoples R China. RP Zonca, F (reprint author), Assoc EURATOM ENEA Fus, CP 65, I-00044 Frascati, Italy. RI chen, liu/I-2297-2013; Zonca, Fulvio/I-8236-2016 OI Zonca, Fulvio/0000-0002-9270-4704 NR 27 TC 53 Z9 53 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD DEC PY 1998 VL 40 IS 12 BP 2009 EP 2021 DI 10.1088/0741-3335/40/12/002 PG 13 WC Physics, Fluids & Plasmas SC Physics GA 154BK UT WOS:000077868000002 ER PT J AU Fedderly, J Compton, E Hartmann, B AF Fedderly, J Compton, E Hartmann, B TI Additive group contributions to density and glass transition temperature in polyurethanes SO POLYMER ENGINEERING AND SCIENCE LA English DT Article; Proceedings Paper CT International Conference on Polymer Characterization CY JAN 08-10, 1997 CL UNIV N TEXAS, DENTON, TEXAS HO UNIV N TEXAS AB The method of additive properties was applied to the density and glass transition temperature, T-g, Of linear amorphous polyurethanes. This method assumes that certain polymer properties result from the additive effects of unique constituent group properties and that these group properties are independent of their environment. To determine the component properties, 14 model polyurethanes were synthesized. The polymers contained only the following four groups: urethane, phenylene, methylene, and ether oxygen. The densities and T-g'S of these polymers were measured. Using these measured values, the known composition of each polymer, and an appropriate additive form, the molar component properties were calculated using a matrix least-squares simultaneous fit algorithm. An error analysis confirmed that the component values were determined with greater accuracy than literature results. The densities ranged from 1.0 to 1.2 g/cm(3) and measured versus predicted densities agreed to within 0.3% on the average. T-g'S ranged from -70 degrees C to 70 degrees C and measured versus predicted T-g'S agreed to within 1.3% on the average. C1 USN, Ctr Surface Warfare, Polymer Sci Grp, W Bethesda, MD 20817 USA. RP Fedderly, J (reprint author), USN, Ctr Surface Warfare, Polymer Sci Grp, W Bethesda, MD 20817 USA. NR 5 TC 2 Z9 2 U1 2 U2 4 PU SOC PLASTICS ENG INC PI BROOKFIELD PA 14 FAIRFIELD DR, BROOKFIELD, CT 06804-0403 USA SN 0032-3888 J9 POLYM ENG SCI JI Polym. Eng. Sci. PD DEC PY 1998 VL 38 IS 12 BP 2072 EP 2076 DI 10.1002/pen.10377 PG 5 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA 157YV UT WOS:000078090000015 ER PT J AU Bunce, J Boatman, J Waddell, J AF Bunce, J Boatman, J Waddell, J TI Unmanned underwater vehicles: Technology demonstration 2 SO SEA TECHNOLOGY LA English DT Article C1 USN, Oceanog Off, Ocean Projects Div, Stennis Space Ctr, MS 39529 USA. USN, Meteorol & Oceanog Command, Stennis Space Ctr, MS 39529 USA. RP Bunce, J (reprint author), USN, Oceanog Off, Ocean Projects Div, Stennis Space Ctr, MS 39529 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 USA SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD DEC PY 1998 VL 39 IS 12 BP 25 EP 28 PG 4 WC Engineering, Ocean SC Engineering GA 156WT UT WOS:000078025900004 ER PT J AU Zolper, JC AF Zolper, JC TI A review of junction field effect transistors for high-temperature and high-power electronics SO SOLID-STATE ELECTRONICS LA English DT Review ID 6H-SIC SUBSTRATE; JFET; DEVICES; GAN AB The status of GaAs, SIC and GaN junction field effect transistors (JFETs) is reviewed with a focus on their application to high temperature and high power operation. The advantage of the JFET structure for this operation regime is detailed. Future directions for junction gated transistors are outlined. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Off Naval Res, Div Elect, Arlington, VA 22217 USA. RP Zolper, JC (reprint author), Off Naval Res, Div Elect, Code 312,800 N Quincy St, Arlington, VA 22217 USA. NR 19 TC 66 Z9 67 U1 1 U2 15 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1101 J9 SOLID STATE ELECTRON JI Solid-State Electron. PD DEC PY 1998 VL 42 IS 12 BP 2153 EP 2156 DI 10.1016/S0038-1101(98)00210-X PG 4 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 147NM UT WOS:000077573500005 ER PT J AU Yater, JE Shih, A Abrams, R AF Yater, JE Shih, A Abrams, R TI Electronic properties of diamond for high-power device applications SO SOLID-STATE ELECTRONICS LA English DT Article ID EMISSION PROPERTIES; SINGLE-CRYSTAL; SEMICONDUCTORS; FABRICATION; TRANSPORT; CATHODES; AFFINITY; SURFACES; FILMS; ANGLE AB The generation and transport of impact-ionized electrons in diamond are investigated using secondary electron emission spectroscopy. By studying secondary electron emission from diamond surfaces having a negative electron affinity (NEA), the total transmitted intensity and the full energy spectrum of the internal electrons are revealed in the measurements. Electron yield and energy distribution measurements from C(100) and CVD diamond samples are analyzed as a function of incident beam energy and information is obtained on both the internal gain and electron energy distribution following impact ionization as well as the effects of the transport process on the internal electron distribution. High internal gain and efficient electron transport are inferred from an analysis of the very high yields measured from both samples. In fact, by fitting calculated yield curves to the measured yield data, we deduce a lower limit on the electron escape depth of similar to 5 mu m and similar to 1.3 mu m in the C(100) and CVD diamond samples, respectively. Energy spectra measured from the diamond samples contain an intense, low-energy peak whose energy position and width are independent of incident beam energy. Based on an analysis of the energy distribution data, a model of the impact-ionization process in diamond is presented. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Yater, JE (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 20 TC 13 Z9 14 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1101 J9 SOLID STATE ELECTRON JI Solid-State Electron. PD DEC PY 1998 VL 42 IS 12 BP 2225 EP 2232 DI 10.1016/S0038-1101(98)00219-6 PG 8 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 147NM UT WOS:000077573500014 ER PT J AU Blache, V Forster, J Jain, H Kanert, O Kuchler, R Ngai, KL AF Blache, V Forster, J Jain, H Kanert, O Kuchler, R Ngai, KL TI Ionic motion in lithium silicophosphate glasses by nuclear spin relaxation and electrical conductivity SO SOLID STATE IONICS LA English DT Article; Proceedings Paper CT 11th International Conference on Solid State Ionics (SSI-11) CY NOV 16-21, 1997 CL HONOLULU, HI SP Int Soc Solid State Ion, Univ Hawaii, Coll Engn ID LOW-FREQUENCY EXCITATIONS; MAGNETIC-RESONANCE; CONDUCTORS; TRANSPORT; NMR; MODEL; ELECTROLYTES AB The diffusive motion of Li+ ions has been investigated in lithium silicophosphate glasses between 300 K and the glass transition temperature by means of Li-7 and P-31 nuclear spin relaxation and electrical conductivity experiments. The data are analyzed in terms of the coupling model. The effects of the mobile cation concentration and of the nature of the network atoms on the ionic transport properties have been determined. The results are interpreted in view of various theoretical approaches. Moreover, we are able to observe an additional fast relaxation process which is related to local rearrangements of the network atoms (beta-process). As this process is only detected by nuclear spin relaxation and not by conductivity, we conclude that the underlying mechanism is caused by local rearrangements of uncharged [PO4](0) tetrahedra belonging to the glassy network. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Dortmund, Inst Phys, D-44221 Dortmund, Germany. Lehigh Univ, Bethlehem, PA 18015 USA. USN, Res Lab, Washington, DC 20375 USA. RP Kuchler, R (reprint author), Univ Dortmund, Inst Phys, D-44221 Dortmund, Germany. EM reiner@e3.physik.uni-dort-mund.de NR 37 TC 12 Z9 12 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD DEC PY 1998 VL 113 SI SI BP 723 EP 731 DI 10.1016/S0167-2738(98)00335-X PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 154BU UT WOS:000077868800100 ER PT J AU Stoloff, PH Garcia, FE Thomason, JE Shia, DS AF Stoloff, PH Garcia, FE Thomason, JE Shia, DS TI A cost-effectiveness analysis of shipboard telemedicine SO TELEMEDICINE JOURNAL LA English DT Article AB Background: The U.S. Navy is considering the installation of telemedicine equipment on more than 300 ships. Besides improving the quality of care, benefits would arise from avoiding medical evacuations (MEDEVACs) and returning patients to work more quickly. Because telemedicine has not yet been fully implemented by the Navy, we relied on projections of anticipated savings and costs, rather than actual expenditures, to determine cost-effectiveness. Objectives: To determine the demand for telemedicine and the cost-effectiveness of various technologies (telephone and fax, e-mail and Internet, video teleconferencing (VTC), teleradiology, and diagnostic instruments), as well as their bandwidth requirements. Methods: A panel of Navy medical experts with telemedicine experience reviewed a representative sample of patient visits collected over a 1-year period and estimated the man-day savings and quality-of-care enhancements that might have occurred had telemedicine technologies been available. The savings from potentially avoiding MEDEVACs was estimated from a survey of ships' medical staff. These sample estimates were then projected to the medical workload of the entire fleet. Off-the-shelf telemedicine equipment prices were combined with installation, maintenance, training, and communication costs to obtain the lifecycle costs of the technology. Results and Conclusions: If telemedicine were available to the fleet, ship medical staffs would initiate nearly 19,000 consults in a year-7% of all patient visits. Telemedicine would enhance quality of care in two-thirds of these consults. Seventeen percent of the MEDEVACs would be preventable with telemedicine (representing 155,000 travel miles), with a savings of $4400 per MEDEVAC. If the ship's communication capabilities were available, a-mail and Internet and telephone and fax would be cost-effective on all ships (including small ships and submarines). Video teleconferencing would be cost-effective on large ships (aircraft carriers and amphibious) only. Teleradiology would be cost-effective on carriers only. Telemedicine's bandwidth requirement is small-1% of a month's time. However, if the ships' medical departments need to resort to a commercial satellite, E-mail and Internet would be the only telemedicine modality generating enough monetary benefits to offset the costs. C1 USN, Ctr Analyses, Alexandria, VA 22302 USA. RP Stoloff, PH (reprint author), USN, Ctr Analyses, 4401 Ford Ave,POB 16268, Alexandria, VA 22302 USA. NR 3 TC 11 Z9 11 U1 0 U2 2 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1078-3024 J9 TELEMED J JI Telemed. J. PD WIN PY 1998 VL 4 IS 4 BP 293 EP 304 DI 10.1089/tmj.1.1998.4.293 PG 12 WC Health Care Sciences & Services SC Health Care Sciences & Services GA 160XM UT WOS:000078257400004 PM 10220469 ER PT J AU Gonzalez, AJ Ahlers, R AF Gonzalez, AJ Ahlers, R TI Context-based representation of intelligent behavior in training simulations SO TRANSACTIONS OF THE SOCIETY FOR COMPUTER SIMULATION INTERNATIONAL LA English DT Article DE training; context-based reasoning; tactical training systems; military simulation; autonomous intelligent platforms; intelligent simulation AB This article presents, describes and evaluates a novel behavior representation paradigm that can effectively and efficiently be used to model the behavior of intelligent entities in a simulation. Called Context-based Reasoning (CxBR), this paradigm is designed to be applicable whenever simulation of human behavior is required. However, it is especially well suited to representing tactical behavior of opponents and teammates in simulation-based tactical training systems. Representing human behavior in a simulation is a complex and difficult task that generally requires significant investment in human effort as well as in computing resources. Conciseness and simplicity of representation and efficiency of computation, therefore, are important issues when developing models of intelligent opponents. We believe that this paradigm is an improvement over the rule-based approach, currently a common technique used in representing human behavior. We have preliminarily tested CxBR in two different prototype systems. Evaluation of the prototype shows that the context-based paradigm promises to meet the desired levels of simplicity, conciseness and efficiency required for the task. C1 Univ Cent Florida, Dept Elect & Comp Engn, Orlando, FL 32816 USA. USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. RP Gonzalez, AJ (reprint author), Univ Cent Florida, Dept Elect & Comp Engn, POB 162450, Orlando, FL 32816 USA. EM gonzalez@ucf.edu NR 35 TC 24 Z9 24 U1 0 U2 1 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA SN 0740-6797 J9 T SOC COMPUT SIMUL I JI Trans. Soc. Comput. Simul. PD DEC PY 1998 VL 15 IS 4 BP 153 EP 166 PG 14 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering SC Computer Science GA 171HY UT WOS:000078858600002 ER PT J AU Lewis, I AF Lewis, I TI The Civil Reserve Air Fleet: Balancing risks and incentives SO TRANSPORTATION JOURNAL LA English DT Article C1 USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93943 USA. RP Lewis, I (reprint author), USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93943 USA. NR 30 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC TRANSPORTATION LOGISTICS, INC PI LOCK HAVEN PA 216 E CHURCH ST, LOCK HAVEN, PA 17745 USA SN 0041-1612 J9 TRANSPORT J JI Transp. J. PD WIN PY 1998 VL 38 IS 2 BP 32 EP 39 PG 8 WC Management; Transportation SC Business & Economics; Transportation GA 171XM UT WOS:000078889800003 ER PT J AU Miller, OF Rineer, SK Reichard, SR Buckley, RG Donovan, MS Graham, IR Goff, WB Kane, CJ AF Miller, OF Rineer, SK Reichard, SR Buckley, RG Donovan, MS Graham, IR Goff, WB Kane, CJ TI Prospective comparison of unenhanced spiral computed tomography and intravenous urogram in the evaluation of acute flank pain SO UROLOGY LA English DT Article ID EXCRETORY UROGRAPHY; HELICAL CT; URETERAL OBSTRUCTION; UNITED-STATES; MR UROGRAPHY; UROLITHIASIS; DIAGNOSIS; CALCULI; SONOGRAPHY; FREQUENCY AB Objectives. To prospectively compare the diagnostic ability of unenhanced spiral computed tomography (NCCT) and intravenous urogram (IVU) in the evaluation of adults with acute flank pain. Methods. After giving informed consent, 106 adult patients with acute flank pain suspected of having urolithiasis underwent NCCT followed by IVU. Subsequent follow-up was scheduled within 72 hours in the Urology Clinic. Each NCCT was read by a single radiologist who was unaware of clinical history and IVU results. Each IVU was read by a different radiologist who was unaware of clinical history and NCCT results. Sensitivity, specificity, and positive and negative predictive values were determined for NCCT and IVU. Results. The diagnosis of ureterolithiasis was defined as unequivocal evidence of urolithiasis on either NCCT or IVP. Seventy-five of 106 patients evaluated were diagnosed with ureterolithiasis. Clinical follow-up was available in 74 (98%) stone patients and in 31 (100%) of 31 non-stone patients. In 72 of the 75 patients diagnosed with ureteral calculi, the NCCT made the diagnosis. IVU made the diagnosis in 65 of the 75 patients. Of the 51 patients without ureterolithiasis, the NCCT was negative in all cases. IVU was negative in 29 of the 31 cases. Unenhanced spiral CT was 96% sensitive and 100% specific (P < 0.001). IVU was 87% sensitive and 94% specific (P < 0.001). Compared with IVU, using the log odds ratio and Fisher's exact test, NCCT was significantly better able to predict the presence of urolithiasis (P = 0.015). Conclusions. NCCT accurately diagnoses ureterolithiasis in patients presenting with acute flank pain. NCCT is significantly better than IVU in determining the presence of urolithiasis. C1 USN, Med Ctr, Dept Clin Res, San Diego, CA 92134 USA. USN, Med Ctr, Dept Urol, San Diego, CA 92134 USA. USN, Med Ctr, Dept Emergency Med, San Diego, CA 92134 USA. USN, Med Ctr, Dept Radiol, San Diego, CA 92134 USA. RP Miller, OF (reprint author), USN, Med Ctr, Dept Clin Res, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 23 TC 117 Z9 120 U1 0 U2 2 PU CAHNERS PUBL CO PI NEW YORK PA 249 WEST 17 STREET, NEW YORK, NY 10011 USA SN 0090-4295 J9 UROLOGY JI UROLOGY PD DEC PY 1998 VL 52 IS 6 BP 982 EP 987 DI 10.1016/S0090-4295(98)00368-9 PG 6 WC Urology & Nephrology SC Urology & Nephrology GA 141EV UT WOS:000077130400007 PM 9836541 ER PT J AU Jata, KV Vasudevan, AK Bales, TT AF Jata, KV Vasudevan, AK Bales, TT TI International Conference on Crystallographic Texture and Mechanical Anisotropy - 1-5 September 1997 - Hyannis, Masschusetts - Preface SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Editorial Material C1 USAF, Res Lab, Mat Directorate, Washington, DC 20330 USA. Off Naval Res, Arlington, VA 22217 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Jata, KV (reprint author), USAF, Res Lab, Mat Directorate, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD NOV 30 PY 1998 VL 257 IS 1 BP XI EP XI PG 1 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 147LZ UT WOS:000077570400002 ER PT J AU Jata, KV Panchanadeeswaran, S Vasudevan, AK AF Jata, KV Panchanadeeswaran, S Vasudevan, AK TI Evolution of texture, microstructure and mechanical property anisotropy in an Al-Li-Cu alloy SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Crystallographic Texture and Mechanical Anisotropy CY SEP 01-05, 1997 CL CAPE COD, MASSACHUSETTS SP USAF, Res Lab Adv Metall, NASA, Off Naval Res, Engn Fdn DE Al-Li-Cu alloy; texture; microstructure; anisotropy ID ROLLING TEXTURES; RECRYSTALLIZATION; DEFORMATION AB The evolution of hot deformation texture, microstructure and yield strength anisotropy in an Al-Li-Cu alloy AF/C489 was studied in the as-extruded, solution heat treated and peak-aged condition. Cast AF/C489 alloy with a random texture was extruded at six temperatures ranging from 260 to 538 degrees C and immediately quenched to capture texture and microstructure at the extrusion temperature. In the as-extruded condition, significant amounts of the major rolling texture components, namely, Br {112}[110], S {123}[634] and Cu {112}[111] were observed at all extrusion temperatures. However, at extrusion temperatures above 480 degrees C there was a sharp rise in the intensity of Br component. When the extruded alloy was solution treated the Br intensity remained stable for the two highest extrusion temperatures. However, solution heat treatment (SHT) following extrusion at lower temperatures resulted in the loss of all the rolling texture components including Br. Furthermore, the solution heat treatment following extrusion at temperatures below 330 degrees C showed presence of significant amount of ND rotated cube ({100}[130]). It is suggested that formation of Br texture may be due to the development of shear bands. Increase in dynamic recovery at high extrusion temperature enhances the shear banding tendency and consequently increased presence of Br. This is consistent with negligible recrystallization during solution treatment following elevated temperature extrusion as observed by optical microscopy. Significant recrystallization during SHT following low temperature extrusion results in the presence of rotated cube components. This is consistent with the presence of more particles at low temperature as observed by transmission electron microscopy. The yield stress anisotropy in the SHT material is attributed to crystallographic texture in the SHT material whereas in the extruded case the anisotropy is due to the combined effect of particles and texture. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, Mat Dev & Proc Branch, Wright Patterson AFB, OH 45433 USA. Alumax Tech Ctr, Golden, CO 80403 USA. Off Naval Res, Arlington, VA 22217 USA. RP Jata, KV (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Mat Dev & Proc Branch, Wright Patterson AFB, OH 45433 USA. EM jatakv@ml.wpafb.af.mil NR 18 TC 22 Z9 27 U1 3 U2 10 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD NOV 30 PY 1998 VL 257 IS 1 BP 37 EP 46 DI 10.1016/S0921-5093(98)00822-3 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 147LZ UT WOS:000077570400006 ER PT J AU Prinz, GA AF Prinz, GA TI Device physics - Magnetoelectronics SO SCIENCE LA English DT Review ID MAGNETORESISTANCE AB An approach to electronics is emerging that is based on the up or down spin of the carriers rather than on electrons or holes as in traditional semiconductor electronics. The physical basis for the observed effects is presented, and the initial successful applications of this technology for information storage are reviewed. Additional opportunities for the exploitation of this technology, which are currently under study, are described. C1 USN, Res Lab, Washington, DC 20375 USA. RP Prinz, GA (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 12 TC 2953 Z9 2998 U1 21 U2 173 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD NOV 27 PY 1998 VL 282 IS 5394 BP 1660 EP 1663 DI 10.1126/science.282.5394.1660 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 143GJ UT WOS:000077246600034 ER PT J AU Ervin, AM Ewing, KJ Nau, G Rowley, DA Lamontagne, RA Aggarwal, ID AF Ervin, AM Ewing, KJ Nau, G Rowley, DA Lamontagne, RA Aggarwal, ID TI Investigation of a robust flow-through Cu(I) optical sensor using 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline immobilized into a Nafion film SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article DE fiber optic; absorption spectroscopy; copper; bathocuproine; nafion AB A robust optical sensor for detection of Cu(I) in water and using fiber optic interrogation is demonstrated. The reagent bathocuproine (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline or BCP) is immobilized into a film of Nafion and the absorbance changes associated with the formation of a Cu(I)-BCP complex are used to detect and quantify Cu(I) in water. The response of the sensor is determined for varying concentrations of Cu(I) in water. Two different measurement techniques are investigated. In the recycled technique the Cu(I)-BCP complex is eluted with 0.1 M nitric acid after each measurement, whereas in the continuous technique the sensor is exposed to consecutively larger concentrations of Cu(I). Detection of ppb levels of Cu(I) is demonstrated and calibration curves for both techniques are constructed. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. Battelle Edgewood, Bel Air, MD 21015 USA. USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. George Washington Univ, Dept Chem, Washington, DC 20052 USA. RP Ervin, AM (reprint author), USN, Res Lab, Div Chem, Code 6116, Washington, DC 20375 USA. NR 10 TC 14 Z9 15 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD NOV 26 PY 1998 VL 53 IS 1-2 BP 104 EP 110 DI 10.1016/S0925-4005(98)00299-8 PG 7 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 153XL UT WOS:000077858600014 ER PT J AU Glaser, ER Kennedy, TA Carlos, WE Ruden, PP Nakamura, S AF Glaser, ER Kennedy, TA Carlos, WE Ruden, PP Nakamura, S TI Recombination processes in InxGa1-xN light-emitting diodes studied through optically detected magnetic resonance SO APPLIED PHYSICS LETTERS LA English DT Article ID QUANTUM-WELLS; GAN; SINGLE AB Optically detected magnetic resonance (ODMR) has been observed on photoluminescence from InGaN light-emitting diodes (LEDs) under low photoexcitation conditions. The samples have the usual p-i-n structure but without etching or metallizations. Distinct ODMR features from the recombining electron and hole are found with strength that indicates significant charge separation and long lifetimes (>100 ns). The electron and hole g tensors are determined for green and extra-blue LEDs. The recombination is assigned to electrons in the InGaN quantum well (QW) and holes either bound at Mg acceptors outside the well or localized at potential minima in the QW but spatially separated from the electrons. (C) 1998 American Institute of Physics. [S0003-6951(98)04347-2]. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Minnesota, Dept Elect & Comp Engn, Minneapolis, MN 55455 USA. Nichia Chem Ind Ltd, Tokushima 774, Japan. RP Glaser, ER (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM glaser@bloch.nrl.navy.mil NR 23 TC 13 Z9 13 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 23 PY 1998 VL 73 IS 21 BP 3123 EP 3125 DI 10.1063/1.122693 PG 3 WC Physics, Applied SC Physics GA 140AR UT WOS:000077063800034 ER PT J AU Fuller, J Breda, AC Carlin, RT AF Fuller, J Breda, AC Carlin, RT TI Ionic liquid-polymer gel electrolytes from hydrophilic and hydrophobic ionic liquids SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Article; Proceedings Paper CT Electrochemical-Society Symposium on Processes in Polymers and Polymer/Metal Interfaces CY MAY 04-09, 1997 CL MONTREAL, CANADA SP Electrochem Soc DE ionic liquid-polymer gels; ionic conductivities; metathesis reaction ID TEMPERATURE MOLTEN-SALTS AB Ionic liquid-polymer gels were prepared by incorporating hydrophilic EMIBF4 and EMI(triflate) (EMI+ = 1-ethyl-3-methylimidazolium) and hydrophobic BMIPF6 (BMI+ = 1-(1-butyl)-3-methylimidazolium) room-temperature ionic liquids into a poly(vinylidene fluoride)-hexafluoropropylene copolymer (PVdF(HFP)) matrix. Gel electrolytes prepared with ionic liquid:PVdF(HFP) mass ratios of 2:1 exhibited ionic conductivities of > 10(-3) S cm(-1) at room temperature and > 10(-2) S cm(-1) at 100 degrees C. The BMIPF6-PVdF(HFP) gel was incorporated into electrochemical cells, employing graphite intercalation electrodes for both the anode and cathode, to construct single and bipolar cells displaying open-circuit voltages of 3.77 and 7.86 V, respectively. New inexpensive preparative routes for the hydrophilic ionic liquids were developed that utilize the metathesis reaction of EMICl with the appropriate ammonium salt in acetone or acetonitrile to produce high purity products. (C) 1998 Elsevier Science S.A. All rights reserved. C1 SAF, AQRT, Washington, DC 20330 USA. Foster Miller, Waltham, MA 02154 USA. Off Naval Res, Arlington, VA 22217 USA. RP Fuller, J (reprint author), SAF, AQRT, 1060 AF Pentagon, Washington, DC 20330 USA. NR 22 TC 254 Z9 260 U1 10 U2 96 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-0728 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD NOV 23 PY 1998 VL 459 IS 1 BP 29 EP 34 DI 10.1016/S0022-0728(98)00285-X PG 6 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA 153PW UT WOS:000077842300004 ER PT J AU Aha, DW AF Aha, DW TI The omnipresence of case-based reasoning in science and application SO KNOWLEDGE-BASED SYSTEMS LA English DT Article; Proceedings Paper CT 17th SGES International Conference on Knowledge-Based Systems and Applied Artificial Intelligence (Expert Systems 97) CY DEC 15-17, 1997 CL CAMBRIDGE, ENGLAND SP British Comp Soc Specialist Grp Expert Syst (BCS-SGES) DE case-based reasoning; machine learning; lazy learning ID LAZY LEARNING ALGORITHMS; NEAREST-NEIGHBOR; CLOUD CLASSIFICATION; NEURAL-NETWORK; SELECTION; ERROR; KNOWLEDGE; INSTANCES; LEARNERS; MODEL AB A surprisingly large number of research disciplines have contributed towards the development of knowledge on lazy problem solving, which is characterized by its storage of ground cases and its demand-driven response to queries. Case-based reasoning (CBR) is an alternative, increasingly popular approach for designing expert systems that implements this approach. This paper lists pointers to some contributions in some related disciplines that offer insights for CBR research. We then outline a small number of Navy applications based on this approach that demonstrate its breadth of applicability. Finally, we list a few successful and failed attempts to apply CBR, and list some predictions on the future roles of CBR in applications. Published by Elsevier Science B.V. C1 USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. RP Aha, DW (reprint author), USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Code 5510, Washington, DC 20375 USA. EM aha@aic.nlr.navy.mil NR 135 TC 73 Z9 83 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0950-7051 J9 KNOWL-BASED SYST JI Knowledge-Based Syst. PD NOV 23 PY 1998 VL 11 IS 5-6 BP 261 EP 273 DI 10.1016/S0950-7051(98)00066-5 PG 13 WC Computer Science, Artificial Intelligence SC Computer Science GA 153FJ UT WOS:000077821800002 ER PT J AU Campillo, AJ Eversole, JD Lin, HB AF Campillo, AJ Eversole, JD Lin, HB TI Comment on "Morphology-dependent stimulated Raman scattering imaging" [J. Chem. Phys. 105, 7276 (1996)] SO JOURNAL OF CHEMICAL PHYSICS LA English DT Letter ID LIQUID AEROSOL INTERFACE; ATMOSPHERIC CHEMISTRY; SPECTROSCOPIC TOUR C1 USN, Res Lab, Opt Phys Branch, Washington, DC 20375 USA. RP Campillo, AJ (reprint author), USN, Res Lab, Opt Phys Branch, Code 5610, Washington, DC 20375 USA. NR 13 TC 8 Z9 8 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 22 PY 1998 VL 109 IS 20 BP 9199 EP 9200 DI 10.1063/1.477474 PG 2 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 139QE UT WOS:000077039900054 ER PT J AU Magdziarz, P Blaes, OM Zdziarski, AA Johnson, WN Smith, DA AF Magdziarz, P Blaes, OM Zdziarski, AA Johnson, WN Smith, DA TI A spectral decomposition of the variable optical, ultraviolet and X-ray continuum of NGC 5548 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; galaxies : individual : NGC 5548; galaxies : Seyfert; ultraviolet : galaxies; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; BROAD-LINE REGION; SHORT-TIMESCALE VARIABILITY; AGNS ACCRETION DISK; NON THERMAL SOURCE; SEYFERT-GALAXIES; MULTIWAVELENGTH OBSERVATIONS; ANISOTROPIC ILLUMINATION; CORONA MODEL; BLACK-HOLES AB We present an analysis and decomposition of the broad-band optical/UV/X-ray/gamma-ray spectrum of the Seyfert 1 galaxy NGC 5548. The spectrum consists of an average of simultaneous optical/IUE/Ginga observations accompanied by ROSAT and CGRO/OSSE data from non-simultaneous observations. We show that the overall optical/UV/X-ray/gamma-ray spectrum can be deconvolved into three basic continuum components: a cool multitemperature blackbody, a hard thermal Comptonized component and an EUV/soft X-ray component well described by a thermal Comptonization continuum. Assuming that the opticaL/IUE spectrum comes from a cold disc, the maximum disc temperature is very well constrained by the data to be kT(disc) = 3.2(-0.2)(+0.2) eV. This rules out models explaining the soft excess as a far tail of the disc spectrum. We show that the soft excess inferred by the data requires a separate continuum component, which is consistent with thermal Comptonization in optically thick (tau similar to 30), warm (similar to 0.3 keV) plasma. This Comptonization component contains a significant fraction of the source energy. The plasma parameters of the hard continuum (tau similar to 2, kT(HC) similar to 50 keV) are consistent with those suggested for the average spectrum of Seyferts, On the basis of the broad-band spectral model, we also re-analyse the simultaneous IUE/Ginga campaign. We find that the fluxes in all three continuum components are positively correlated, The total flux emitted in the hard component is positively correlated with both the spectral index and the solid angle of cold matter seen by the hot source. Such a correlation suggests that the variability mechanism is related to changes in the geometry of the continuum-emitting regions, and an excess in the amount of reflection requires deviations from a simple plane disc picture. The variations in the hard spectral index can then be explained by increased cooling of the hot plasma caused by the increased number of seed photons. We suggest that the geometry variations may be related to a transition region between a cold and a hot disc. C1 Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Nicholas Copernicus Astron Ctr, PL-00716 Warsaw, Poland. USN, Res Lab, Washington, DC 20375 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Jagiellonian Univ, Astron Observ, Krakow, Poland. RI Johnson, Neil/G-3309-2014 NR 90 TC 80 Z9 80 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD NOV 21 PY 1998 VL 301 IS 1 BP 179 EP 192 DI 10.1046/j.1365-8711.1998.02015.x PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 147MB UT WOS:000077570600024 ER PT J AU Garland, NL McElvany, SW AF Garland, NL McElvany, SW TI Ionization potentials of TNAZ and its decomposition products SO CHEMICAL PHYSICS LETTERS LA English DT Article ID THERMAL-DECOMPOSITION; ENERGETIC MATERIALS; NTO; 1,3,3-TRINITROAZETIDINE; RDX AB The ionization potentials (IPs) of 1,3,3-trinitroazetidine (TNAZ) and its thermal decomposition products were determined using charge-transfer bracketing experiments in a Fourier transform mass spectrometer. The products included: 1-nitroso-3,3-dinitroazetidine (NDNAZ); 3,3-dinitroazetidine (DNAZ); and the C3H3N3O4 fragment resulting from loss of HONO from TNAZ. The IP of TNAZ is 10.36 (+/-0.1) eV, the IP of NDNAZ is 9.52 (+/-0.1) eV, and the IPs of DNAZ and the C3H3N3O4 Fragment are each 9.8 (+/-0.1) eV. These results are used to estimate relative product yields in previous TNAZ decomposition experiments which employed mass spectrometry for product detection. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Garland, NL (reprint author), USN, Res Lab, Div Chem, Code 6110, Washington, DC 20375 USA. NR 20 TC 6 Z9 6 U1 0 U2 0 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 NOV 20 PY 1998 VL 297 IS 1-2 BP 147 EP 153 DI 10.1016/S0009-2614(98)01113-0 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 140UW UT WOS:000077107600022 ER PT J AU Giraldo, FX AF Giraldo, FX TI The Lagrange-Galerkin spectral element method on unstructured quadrilateral grids SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE advection-diffusion equation; finite element; flux-corrected transport (fct); icosahedral grid; Lagrange-Galerkin; Legendre polynomial; semi-Lagrangian; spectral element; unstructured grid ID SHALLOW-WATER EQUATIONS; STOKES EQUATIONS; SCHEMES; MODEL; FLOW AB The purpose of this paper is to introduce a new method formed by fusing the Lagrange-Galerkin and spectral element methods. The Lagrange-Galerkin method traces the characteristic curves of the solution and, consequently, is very well suited for resolving the nonlinearities introduced by the advection operator of the fluid dynamics equations. Spectral element methods are essentially higher order finite element methods that exhibit spectral (exponential) convergence, provided that the solution is a smooth function. By combining these two methods, a numerical scheme can be constructed that resolves, with extremely high precision, the nonlinearities of the advection terms and the smooth regions of the flow generated by the diffusion terms. This paper describes the construction of the Lagrange-Galerkin spectral element method which permits the use of any grid type including unstructured grids. The only restriction at the moment is that the grid elements be quadrilaterals. The stability analysis of both methods demonstrates why these two methods are so powerful individually and how their fusion leads to an improved scheme. The Lagrange-Galerkin spectral element method is validated using the 1D and 2D advection and advection-diffusion equations. The results of the stability analysis and the numerical experiments demonstrate the utility of such an approach. (C) 1998 Academic Press. C1 USN, Res Lab, Monterey, CA 93943 USA. RP Giraldo, FX (reprint author), USN, Res Lab, Monterey, CA 93943 USA. NR 15 TC 43 Z9 43 U1 0 U2 2 PU ACADEMIC PRESS INC 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 NOV 20 PY 1998 VL 147 IS 1 BP 114 EP 146 DI 10.1006/jcph.1998.6078 PG 33 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 143JW UT WOS:000077252900005 ER PT J AU Randall, CE Rusch, DW Bevilacqua, RM Hoppel, KW Lumpe, JD AF Randall, CE Rusch, DW Bevilacqua, RM Hoppel, KW Lumpe, JD TI Polar Ozone and Aerosol Measurement (POAM) II stratospheric NO2, 1993-1996 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID WAVE SPECTROSCOPIC MEASUREMENTS; HIGH-LATITUDE STRATOSPHERE; MIDDLE ATMOSPHERE; REACTIVE NITROGEN; NITRIC-ACID; CHLORINE DEACTIVATION; 2-DIMENSIONAL MODEL; ODD-NITROGEN; SOUTH-POLE; LONG-TERM AB We describe, for the first time, measurements of stratospheric nitrogen dioxide (NO2) by the Polar Ozone and Aerosol Measurement (POAM II) instrument. Measurements span October 1993 through mid-November 1996 and cover latitude ranges from 55 degrees to 72 degrees N and from 63 degrees to 88 degrees S. Comparisons with coincident satellite and space shuttle observations show good agreement and confirm the validity of POAM II measurements for scientific investigations. Overall seasonal variations in both hemispheres are qualitatively consistent with standard photochemistry. In the austral late winter/early spring of 1994, however, anomalously high NO2 mixing ratios were observed above 22 km. We conclude that these high NO2 levels resulted from downward transport of NOx-enhanced air from the mesosphere or thermosphere inside the polar vortex. Enhanced NO2 mixing ratios in 1994 were factors of similar to 1.3 and 2.5 larger than at the corresponding times in 1995 and 1996. We conclude that FOAM II observations of coincident, localized reductions in ozone of up to 40% were caused by the increased stratospheric NOx via the standard catalytic NOx cycle. C1 Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. USN, Res Lab, Washington, DC 20375 USA. Computat Phys Inc, Fairfax, VA 22301 USA. RP Randall, CE (reprint author), Univ Colorado, Atmospher & Space Phys Lab, Campus Box 392, Boulder, CO 80309 USA. EM cora.randall@lasp.colorado.edu NR 47 TC 63 Z9 63 U1 0 U2 3 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 NOV 20 PY 1998 VL 103 IS D21 BP 28361 EP 28371 DI 10.1029/98JD02092 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 140GF UT WOS:000077078700024 ER PT J AU Bonadeo, NH Erland, J Gammon, D Park, D Katzer, DS Steel, DG AF Bonadeo, NH Erland, J Gammon, D Park, D Katzer, DS Steel, DG TI Coherent optical control of the quantum state of a single quantum dot SO SCIENCE LA English DT Article ID ELECTRON GASES; SPECTROSCOPY; SCATTERING; EXCITONS; PULSES; INTERFERENCE; RELAXATION; TRANSIENTS; SEQUENCES; DYNAMICS AB Picosecond optical excitation was used to coherently control the excitation in a single quantum dot on a time scale that is short compared with the time scale for loss of quantum coherence. The excitonic wave function was manipulated by controlling the optical phase of the two-pulse sequence through timing and polarization. Wave function engineering techniques, developed in atomic and molecular systems, were used to monitor and control a nonstationary quantum mechanical state composed of a superposition of eigenstates. The results extend the concept of coherent control in semiconductors to the limit of a single quantum system in a zero-dimensional quantum dot. C1 Univ Michigan, Harrison M Randall Lab Phys, Ann Arbor, MI 48109 USA. Univ Michigan, Ctr Ultrafast Opt Sci, Ann Arbor, MI 48109 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Michigan, Dept Elect Engn & Comp Sci, Ann Arbor, MI 48109 USA. RP Steel, DG (reprint author), Univ Michigan, Harrison M Randall Lab Phys, Ann Arbor, MI 48109 USA. RI Katzer, D. Scott/N-7841-2013 NR 41 TC 495 Z9 504 U1 6 U2 54 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD NOV 20 PY 1998 VL 282 IS 5393 BP 1473 EP 1476 DI 10.1126/science.282.5393.1473 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 140WA UT WOS:000077110800049 ER PT J AU Thomas, JB Mascarella, SW Burgess, JP Xu, H McCullough, KB Rothman, RB Flippen-Anderson, JL George, CF Cantrell, BE Zimmerman, DM Carroll, FY AF Thomas, JB Mascarella, SW Burgess, JP Xu, H McCullough, KB Rothman, RB Flippen-Anderson, JL George, CF Cantrell, BE Zimmerman, DM Carroll, FY TI N-substituted octahydro-4a-(3-hydroxyphenyl)-10a-methylbenzo[g]isoquinolines are opioid receptor pure antagonists SO BIOORGANIC & MEDICINAL CHEMISTRY LETTERS LA English DT Article AB N-Methyl- and N-phenylethyl-(+/-)-1,2,3,4,4a,5,10,10a-octahydro-4a-(3-hydroxyphenyl)-10a-methyl- benzo[g]isoquinolines (4 and 5, respectively) were found to be pure opioid antagonists. These compounds were shown to share many of the characteristics identified with the N-methyl- and N-phenylethyl trans-3,4-dimethyl-4(3-hydroxyphenyl)piperidine (1 and 2, respectively) including N-substituent mediated potency and a lack of N-substituent mediated antagonism. These data suggest that compounds 4 and 5 and the N-substituted trans-3,4-dimethyl-4-(3-hydroxyphenyl)piperidines (1 and 2) may interact with opioid receptors similarly. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Res Triangle Inst, Res Triangle Pk, NC 27709 USA. NIDA, Addict Res Sect, Clin Psychopharmacol, Baltimore, MD 21224 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. Eli Lilly & Co, Lilly Corp Ctr, Lilly Res Labs, Indianapolis, IN 46285 USA. RP Carroll, FY (reprint author), Res Triangle Inst, POB 12194, Res Triangle Pk, NC 27709 USA. FU NIDA NIH HHS [DA09045] NR 8 TC 5 Z9 5 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0960-894X J9 BIOORG MED CHEM LETT JI Bioorg. Med. Chem. Lett. PD NOV 17 PY 1998 VL 8 IS 22 BP 3149 EP 3152 DI 10.1016/S0960-894X(98)00576-9 PG 4 WC Chemistry, Medicinal; Chemistry, Organic SC Pharmacology & Pharmacy; Chemistry GA 155HW UT WOS:000077941800009 PM 9873693 ER PT J AU Meyer, JR Felix, CL Bewley, WW Vurgaftman, I Aifer, EH Olafsen, LJ Lindle, JR Hoffman, CA Yang, MJ Bennett, BR Shanabrook, BV Lee, H Lin, CH Pei, SS Miles, RH AF Meyer, JR Felix, CL Bewley, WW Vurgaftman, I Aifer, EH Olafsen, LJ Lindle, JR Hoffman, CA Yang, MJ Bennett, BR Shanabrook, BV Lee, H Lin, CH Pei, SS Miles, RH TI Auger coefficients in type-II InAs/Ga1-xInxSb quantum wells SO APPLIED PHYSICS LETTERS LA English DT Article ID MINORITY-CARRIER LIFETIME; ROOM-TEMPERATURE; MU-M; THEORETICAL PERFORMANCE; LASER-EMISSION; RECOMBINATION; SUPERLATTICE; HGCDTE; GAIN; HETEROSTRUCTURES AB Two different approaches, a photoconductive response technique and a correlation of lasing thresholds with theoretical threshold carrier concentrations have been used to determine Auger lifetimes in InAs/GaInSb quantum wells. For energy gaps corresponding to 3.1-4.8 mu m, the room-temperature Auger coefficients for seven different samples are found to be nearly an order-of-magnitude lower than typical type-I results for the same wavelength. The data imply that at this temperature, the Auger rate is relatively insensitive to details of the band structure. (C) 1998 American Institute of Physics. [S0003-6951(98)00746-3]. C1 USN, Res Lab, Washington, DC 20375 USA. Sarnoff Corp, Princeton, NJ 08543 USA. Univ Houston, Ctr Space Vacuum Epitaxy, Houston, TX 77204 USA. Hughes Res Labs, Malibu, CA 90265 USA. RP Meyer, JR (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Bennett, Brian/A-8850-2008; Lindle, James/A-9426-2009; Olafsen, Linda/G-4996-2013 OI Bennett, Brian/0000-0002-2437-4213; NR 34 TC 92 Z9 92 U1 0 U2 20 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 16 PY 1998 VL 73 IS 20 BP 2857 EP 2859 DI 10.1063/1.122609 PG 3 WC Physics, Applied SC Physics GA 136FW UT WOS:000076848700001 ER PT J AU Crum, NF Murray, KM AF Crum, NF Murray, KM TI Breathing space SO AMERICAN FAMILY PHYSICIAN LA English DT Article ID SPONTANEOUS PNEUMOMEDIASTINUM C1 USN, Med Ctr, San Diego, CA 92134 USA. RP Crum, NF (reprint author), USN, Med Ctr, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER ACAD FAMILY PHYSICIANS PI KANSAS CITY PA 8880 WARD PARKWAY, KANSAS CITY, MO 64114-2797 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD NOV 15 PY 1998 VL 58 IS 8 BP 1829 EP 1830 PG 2 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 141XA UT WOS:000077168500013 PM 9835857 ER PT J AU De Marco, R Eriksen, R Zirino, A AF De Marco, R Eriksen, R Zirino, A TI Electrochemical impedance spectroscopy study of the response mechanism of the jalpaite Cu-II ion-selective electrode in seawater SO ANALYTICAL CHEMISTRY LA English DT Article ID MARINE WATERS; CHLORIDE; COPPER; CALIBRATION; MEMBRANE AB This paper presents the results of a novel study into the response mechanism of the jalpaite copper(II) ion-selective electrode(ISE) using electrochemical impedance spectroscopy (EIS) under conditions of minimal overpotential stimulation (i.e., +/-10 mV). The EIS spectra of the jalpaite ISE in seawater and other ionic media revealed a high-frequency surface film impedance that is attributable to the modified hydrated surface layers of the ISE, and a low-frequency charge-transfer impedance that can be ascribed to the reductive ion-exchange of Cu-II at the membrane/electrolyte interface. EIS data for a rotating disk electrode have shown that the charge-transfer process is under diffusion control. MS and potentiometric response data in UV-oxidized seawater spiked with humic acid imply that organic complexation of Cu-I at the electrode diffusion layer is responsible for a weak interference effect. The classical chloride interference effect of the jalpaite Cu-II ISE occurring at high concentrations of Cu-II (i.e., > 10(-6) M) yields an MS response similar to the one observed with organic ligands. An EIS experiment for a jalpaite Cu-II ISE aged in seawater for 72 h demonstrated that the charge-transfer impedance is constant until electrode release of Cu-II exceeds the complexing capacity of seawater, and this mechanistic information is consistent with the hypothesis that electrode dissolution can be used to autotitrate the natural ligands in seawater. C1 Curtin Univ Technol, Sch Appl Chem, Perth, WA 6845, Australia. Univ Tasmania, Dept Phys Sci, Launceston, Tas 7250, Australia. USN, Command Control & Ocean Surveillance Ctr, RDT&E Div, San Diego, CA 95152 USA. RP De Marco, R (reprint author), Curtin Univ Technol, Sch Appl Chem, GPO Box U1987, Perth, WA 6845, Australia. RI De Marco, Roland/F-7213-2011; Eriksen, Ruth/J-7760-2014 OI De Marco, Roland/0000-0002-1357-3727; Eriksen, Ruth/0000-0002-5184-2465 NR 23 TC 15 Z9 15 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD NOV 15 PY 1998 VL 70 IS 22 BP 4683 EP 4689 DI 10.1021/ac980196+ PG 7 WC Chemistry, Analytical SC Chemistry GA 138ZU UT WOS:000077003600006 ER PT J AU Valeri, CR Cassidy, G Lieberthal, W Crowley, J Khuri, S Loscalzo, J AF Valeri, CR Cassidy, G Lieberthal, W Crowley, J Khuri, S Loscalzo, J TI Anemia-induced reversible platelet dysfunction. SO BLOOD LA English DT Meeting Abstract C1 USN, Bld Res Lab, Boston, MA USA. Boston Univ, Sch Med, Boston, MA 02118 USA. Rhode Isl Hosp, Providence, RI USA. Vet Adm Med Ctr W Roxbury, W Roxbury, MA USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 15 PY 1998 VL 92 IS 10 SU 1 MA 3569 BP 139B EP 139B PN 2 PG 1 WC Hematology SC Hematology GA 141AX UT WOS:000077121400588 ER PT J AU Rosler, E Brandt, JE Chute, J Hoffman, R AF Rosler, E Brandt, JE Chute, J Hoffman, R TI Ontogeny related differences in the requirements for optimal ex vivo expansion of primitive hematopoietic cells. SO BLOOD LA English DT Meeting Abstract C1 USN, Med Res Inst, Bethesda, MD USA. Univ Illinois, Chicago, IL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 15 PY 1998 VL 92 IS 10 SU 1 MA 2658 BP 644A EP 644A PN 1 PG 1 WC Hematology SC Hematology GA 141AW UT WOS:000077121302645 ER PT J AU Cipolla, JL Butler, MJ AF Cipolla, JL Butler, MJ TI Infinite elements in the time domain using a prolate spheroidal multipole expansion SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE infinite element; transient; acoustics AB Many phenomena in acoustically loaded structural vibrations are better understood in the time domain, particularly transient radiation, shock, and problems involving non-linearities, cavitation, and bulk structural motion. In addition, the geometric complexity of structures of interest drives the analyst toward domain-discretized solution methods, such as finite elements or finite differences, and large numbers of degrees of freedom. In such methods, efficient numerical enforcement of the Sommerfeld radiation condition in the time domain becomes difficult. Although a great many methodologies for doing so have been demonstrated, there seems to exist no consensus on the optimal numerical implementation of this boundary condition in the time domain. Here, we present theoretical development of several new boundary operators for conventional finite element codes. Each proceeds from successful domain-discretized, projected field-type harmonic solutions, in contrast to boundary integral equation operators or those derived from analyses of outgoing waves. We exploit the separable prolate-spheroidal co-ordinate system, which is sufficiently general for a large variety of problems of naval interest, to obtain finite element-like operators (matrices) for the boundary points. Use of this co-ordinate system results in element matrices that can be analytically inverse transformed from the frequency to the time domain, without imposing continuity requirements on the solution above those imposed by the underlying partial differential equation. In addition, use of element-like boundary operators does not alter the banded structure of assembled system matrices. Results presented here include theoretical derivation of the infinite elements, resolution of the Fourier inversion issues, and element matrices for the boundary operators which introduce no new continuity requirements on the fluid field variable. The simplest infinite elements are verified in a coupled three-dimensional context against DAA2 and Helmholtz integral equation results. (C) 1998 John Wiley & Sons, Ltd. C1 USN, Undersea Warfare Ctr, Div Newport, Newport, RI 02841 USA. RP Cipolla, JL (reprint author), USN, Undersea Warfare Ctr, Div Newport, Code 8322, Newport, RI 02841 USA. EM cipolla@in83e.npt.nuwc.navy.mil NR 39 TC 20 Z9 22 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD NOV 15 PY 1998 VL 43 IS 5 BP 889 EP 908 DI 10.1002/(SICI)1097-0207(19981115)43:5<889::AID-NME433>3.0.CO;2-L PG 20 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 129WA UT WOS:000076486000004 ER PT J AU Sletten, MA Seshadri, SR AF Sletten, MA Seshadri, SR TI Singular perturbation theory of a thin film surface-polariton polarizer for a planar optical waveguide SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID PLASMON RESONANCE; WAVE-GUIDE AB An on-line polarizer of the order of a millimeter in length is designed by locating a thin metal film suitably close and parallel to a dielectric film waveguide. The polarizer transmits the transverse electric guided mode of the dielectric film with negligible insertion loss. As a consequence of the phase-matched wave interaction between the surface polariton supported by the metal film and the transverse magnetic guided mode of the dielectric film, the transverse magnetic guided mode is severely attenuated resulting in a high extinction coefficient. A singular perturbation theory using multiple space scales is developed for the analysis of this thin film surface polariton polarizer for a planar dielectric film optical waveguide and illustrative numerical results are presented. The sensitivity of the performance of the polarizer to small changes in the various physical parameters is examined. (C) 1998 American Institute of Physics. [S0021-8979(98)05722-3]. C1 Univ Wisconsin, Madison, WI 53706 USA. RP Sletten, MA (reprint author), USN, Res Lab, Code 7255,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 14 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 15 PY 1998 VL 84 IS 10 BP 5424 EP 5435 DI 10.1063/1.368305 PG 12 WC Physics, Applied SC Physics GA 133CP UT WOS:000076669100004 ER PT J AU Teague, WJ Perkins, HT Hallock, ZR Jacobs, GA AF Teague, WJ Perkins, HT Hallock, ZR Jacobs, GA TI Current and tide observations in the southern Yellow Sea SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID MODEL AB Determination of mean currents and tides are particularly difficult in coastal regions. Flows are often nongeostrophic and short lived. Bathymetry is frequently not adequately known and can greatly influence coastal dynamics. To better quantify tides and currents in the southern Yellow Sea, three pressure gauges and three acoustic Doppler current profilers (ADCPs) were bottom moored for 4-6 month intervals at depths ranging from 77 to 89 m. Tidal range is over 2 m, and maximum current velocities are between 50 and 80 cm/s at the mooring locations. The present data are analyzed for 13 significant tidal constituents which are found to account for similar to 85% of the sea surface height variability. M2 is the dominant constituent, followed by S2 and K1. Flow is dominated by the tides. Mean currents are relatively small, ranging from similar to 1.5 cm/s at the northern mooring to similar to 4 cm/s at the southern mooring. Delineations of barotropic and depth-dependent currents are made from the ADCP measurements in terms of mean and eddy kinetic energy. Currents are found to be most depth dependent in the near-surface layers. Approximately 85-90% of the eddy kinetic energy is depth independent. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Teague, WJ (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. EM teague@nrlssc.navy.mil NR 18 TC 29 Z9 37 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-OCEANS JI J. Geophys. Res.-Oceans PD NOV 15 PY 1998 VL 103 IS C12 BP 27783 EP 27793 DI 10.1029/98JC02672 PG 11 WC Oceanography SC Oceanography GA 139AF UT WOS:000077004700015 ER PT J AU Lee, ZP Carder, KL Steward, RG Peacock, TG Davis, CO Patch, JS AF Lee, ZP Carder, KL Steward, RG Peacock, TG Davis, CO Patch, JS TI An empirical algorithm for light absorption by ocean water based on color SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID REMOTE-SENSING REFLECTANCE; DIFFUSE ATTENUATION COEFFICIENT; OPTICAL-PROPERTIES; SPECTRAL ABSORPTION; PHYTOPLANKTON ABSORPTION; BIOGENOUS MATTER; NATURAL-WATERS; SARGASSO SEA; MODEL; CHLOROPHYLL AB Empirical algorithms for the total absorption coefficient and absorption coefficient by pigments for surface waters at 440 nm were developed by applying a quadratic formula that combines two spectral ratios of remote-sensing reflectance. For total absorption coefficients ranging from 0.02 to 2.0 m(-1), a goodness of fit was achieved between the measured and modeled data with a root-mean-square difference between the measured and modeled values for log10 scale (RMSDlog10) of 0.062 (15.3% for linear scale, number of samples N = 63), while RMSDlog10 is 0.111 (29.1% for linear scale, N = 126) for pigment absorption (ranging from 0.01 to 1.0 m(-1)). As alternatives to pigment concentration algorithms, the absorption algorithms developed can be applied to the coastal zone color scanner and sea-viewing wide-field-of-view sensor data to derive inherent optical properties of the ocean, For the same data sets, we also directly related the chlorophyll a concentrations to the spectral ratios and obtained an RMSDlog10 value of 0.218 (65.2% for linear scale, N = 120) for concentrations ranging from 0.06 to 50.0 mg m(-3). These results indicate that it is more accurate to estimate the absorption coefficients than the pigment concentrations from remotely sensed data. This is likely due to the fact that for. the broad range of waters studied the pigment-specific absorption coefficient at 440 nm ranged from 0.03 to 0.2 m(2) (mg chl)(-1). As an indirect test of the algorithms developed, the chlorophyll a concentration algorithm is applied to an independent global data set and an RMSDlog10 of 0.191 (55.2% for linear scale, N = 919) is obtained. There is no independent global absorption data set available as yet to test the absorption algorithms. C1 Univ S Florida, Dept Marine Sci, St Petersburg, FL 33701 USA. USN, Res Lab, Washington, DC 20375 USA. RP Lee, ZP (reprint author), Univ S Florida, Dept Marine Sci, 140 7Th Ave S, St Petersburg, FL 33701 USA. EM zplee@marine.usf.edu NR 53 TC 55 Z9 59 U1 2 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD NOV 15 PY 1998 VL 103 IS C12 BP 27967 EP 27978 DI 10.1029/98JC01946 PG 12 WC Oceanography SC Oceanography GA 139AF UT WOS:000077004700027 ER PT J AU Walton, CC Pichel, WG Sapper, JF May, DA AF Walton, CC Pichel, WG Sapper, JF May, DA TI The development and operational application of nonlinear algorithms for the measurement of sea surface temperatures with the NOAA polar-orbiting environmental satellites SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID WATER-VAPOR; AEROSOLS; SPACE; AVHRR AB Since 1990, the NOAA National Environmental Satellite Data and Information Service (NESDIS) has provided satellite-derived sea surface temperature (SST) measurements based on nonlinear SST algorithms, using advanced very high resolution radiometer (AVHRR) multiple-infrared window channel data. This paper develops linear and nonlinear SST algorithms from the radiative transfer equation. It is shown that the nonlinear algorithms are more accurate than linear algorithms but that the functional dependence of the nonlinearity is data dependent. This theoretical discussion (sections 2-4) is followed with a discussion in section 5 of the accuracy over a 9-year period of the satellite-derived SST measurements provided by NOAA NESDIS when compared with coincident drifting buoys. Between 1989 and 1998 the global scatter of the daytime satellite SST against drifting buoy measurements has decreased from similar to 0.8 degrees to 0.5 degrees C, while the nighttime scatter has remained fairly constant at 0.5 degrees C. An exception to these accuracy measurements occurred after the eruption of Mount Pinatubo in June 1991. C1 NOAA, Natl Environm Satellite Data & Informat Serv, Washington, DC 20233 USA. USN, Naval Oceanog Off, Stennis Space Ctr, MS 39529 USA. RP Walton, CC (reprint author), NOAA, Natl Environm Satellite Data & Informat Serv, NSC Room 102,Stop 9910,4700 Silver Hill Rd, Washington, DC 20233 USA. EM wpichel@nesdis.noaa.gov RI Pichel, William/F-5619-2010 OI Pichel, William/0000-0001-6332-0149 NR 45 TC 202 Z9 220 U1 1 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD NOV 15 PY 1998 VL 103 IS C12 BP 27999 EP 28012 DI 10.1029/98JC02370 PG 14 WC Oceanography SC Oceanography GA 139AF UT WOS:000077004700029 ER PT J AU Koh, HJ Kim, NJ Lee, S Lee, EW AF Koh, HJ Kim, NJ Lee, S Lee, EW TI Superplastic deformation behavior of a rapidly solidified Al-Li alloy SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE superplasticity; aluminum-lithium alloys; thermo-mechanical processing; continuous recrystallization; high strain rate; rapid solidification ID MG AB This study aims at investigating the superplastic behavior of a rapidly solidified Al-3Li-1Cu-0.5Mg-0.5Zr (mass%) alloy. Although rapidly solidified AI-Li alloys have the very fine grain structure desirable for improved superplasticity, unfavorable oxide morphology often prevents them from being superplastic. The results of superplastic deformation indicated that the proper thermo-mechanical treatment (TMT) of the alloy resulted in a much improved superplastic ductility, e.g, elongation of approximately 530%. In the case of testing at 520 degrees C, optimum strain rate of forming was 4 x 10(-2) s(-1), which was one or two orders of magnitude higher than that of ingot cast Al-Li alloys. Such a high strain rate was thought to be quite advantageous for the practical application of superplastic deformation of the alloy. It could also be seen that the microstructure of the deformed alloy was similar to that of the as-received or the TMT treated alloy since continuous recrystallization was accomplished by subgrain growth and the growth of primary grains was prevented by fine beta' (Al3Zr) particles. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Pohang Univ Sci & Technol, Ctr Adv Aerosp Mat, Pohang 790784, South Korea. USN, Air Warfare Ctr, Patuxent River, MD 20670 USA. RP Lee, S (reprint author), Pohang Univ Sci & Technol, Ctr Adv Aerosp Mat, Pohang 790784, South Korea. NR 21 TC 7 Z9 7 U1 1 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD NOV 15 PY 1998 VL 256 IS 1-2 BP 208 EP 213 DI 10.1016/S0921-5093(98)00790-4 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 142RF UT WOS:000077213600021 ER PT J AU Nunes, RW Bennetto, J Vanderbilt, D AF Nunes, RW Bennetto, J Vanderbilt, D TI Core reconstruction of the 90 degrees partial dislocation in nonpolar semiconductors SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; SILICON; KINKS; MOBILITY; MOTION; MODEL; SI AB We investigate the energetics of the single-period and double-period core reconstructions of the 90 degrees partial dislocation in the homopolar semiconductors C, Si, and Ge. The double-period geometry is found to be lower in energy in all three materials, and the energy difference between the two geometries is shown to follow the same trends as the energy gap and the stiffness. Both structures are fully reconstructed, consisting entirely of fourfold coordinated atoms. They differ primarily in the detail of the local strains introduced by the two reconstructions in the core region. The double-period structure is shown to introduce smaller average bond-length deviations, at the expense of slightly larger average bond-angle bending distortions, with respect to the single-period core. The balance between these two strain components leads to the lower energy of the double-period reconstruction. [S0163-1829(98)04944-3]. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. George Mason Univ, Fairfax, VA 22030 USA. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. RP USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RI Nunes, Ricardo Wagner/M-9974-2014 OI Nunes, Ricardo Wagner/0000-0003-2810-8649 NR 31 TC 44 Z9 45 U1 2 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1998 VL 58 IS 19 BP 12563 EP 12566 DI 10.1103/PhysRevB.58.12563 PG 4 WC Physics, Condensed Matter SC Physics GA 144CE UT WOS:000077295500009 ER PT J AU Sigalas, MM Rose, JH Papaconstantopoulos, DA Shore, HB AF Sigalas, MM Rose, JH Papaconstantopoulos, DA Shore, HB TI Scaling lengths of elemental metals SO PHYSICAL REVIEW B LA English DT Article ID TOTAL-ENERGY; IDEAL METALS AB The average interstitial electron densities n of the elemental alkali, noble, and transition metals were computed as a function of the lattice spacing using a scalar-relativistic total-energy band-structure code. The calculations showed that the average interstitial electron density varied exponentially as exp(-a/L-D), where a measures the lattice spacing in terms of the equivalent Wigner-Seitz radius. In principle, the value of L-D could be considered to be a new characteristic length for the metals-a density length scale. However, we found that L-D is very nearly proportional to the energy length scale L-E that enters into the definition of the universal bonding energy relations, i.e., L(E)similar to 0.85L(D). Two consequences of this approximate equality are described. First, the normalized cohesive energy can be usefully approximated by a universal function of the normalized interstitial density. Second, the bulk moduli of the elemental metals can be approximately determined from the Wigner-Seitz radius, the bonding valence, and the density length scale. [S0163-1829(98)04244-1]. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. San Diego State Univ, Dept Phys, San Diego, CA 92182 USA. RP Sigalas, MM (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. EM jhrose@iastate.edu NR 12 TC 5 Z9 5 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1998 VL 58 IS 20 BP 13438 EP 13441 DI 10.1103/PhysRevB.58.13438 PG 4 WC Physics, Condensed Matter SC Physics GA 143WF UT WOS:000077279800034 ER PT J AU Olumee, Z Callahan, JH Vertes, A AF Olumee, Z Callahan, JH Vertes, A TI Droplet dynamics changes in electrostatic sprays of methanol-water mixtures SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID FUNCTIONING MODES; ELECTROSPRAY; GENERATION; CHARGE AB Two-dimensional phase Doppler anemometry measurements have been carried out to determine the size and velocity distributions of electrosprayed droplets generated from methanol-water mixtures. We investigated spraying conditions close to those of electrospray ionization sources. The droplet size and the axial and radial velocity distributions were measured as a function of liquid flow rate, needle-to-counter electrode distance, bias voltage, position of the probe volume, and electrical conductivity of the liquid. In 90:10 (v/v) methanol-water mixtures the droplet size decreased from similar to 7 to similar to 1.6 mu m as the conductivity increased as a consequence of a 3 orders of magnitude increase in ionic strength. As the position of the probe volume was moved along the spray axis, two different spray dynamics were observed. Solutions of low conductivity (c < 10(-5) M) on the average produced 5.5 mu m droplets at the capillary that gradually decreased to 4.0 mu m as the drops moved away from the tip. Solutions of higher conductivity (c > 10(-3) M), however, resulted in smaller droplets at the needle (1.6 mu m) that increased in size to 4.2 mu m as the particles traveled toward the counter electrode. The droplet size reduction can be explained by evaporation and/or Coulomb explosion, whereas the increase in droplet size may be the consequence of droplet segregation or coalescence. Axial velocity distributions show compression along the spray axis (e.g., observed at 10 mm similar to 50% reduction of the width at 4 mm is seen). Moving downstream, the average velocity of droplets from water-methanol mixtures decreases monotonically. Solutions containing KCl exhibit a maximum in axial droplet velocity as the probe volume moves away from the capillary. These profile changes can be explained by differences in the electric field distribution along the spray centerline. C1 George Washington Univ, Dept Chem, Washington, DC 20052 USA. USN, Res Lab, Analyt Chem Sect, Washington, DC 20375 USA. RP Vertes, A (reprint author), George Washington Univ, Dept Chem, Washington, DC 20052 USA. RI Vertes, Akos/B-7159-2008 OI Vertes, Akos/0000-0001-5186-5352 NR 24 TC 55 Z9 55 U1 0 U2 15 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 NOV 12 PY 1998 VL 102 IS 46 BP 9154 EP 9160 DI 10.1021/jp982027z PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 141ME UT WOS:000077147100009 ER PT J AU Kim, CS Mowrey, RC Butler, JE Russell, JN AF Kim, CS Mowrey, RC Butler, JE Russell, JN TI Photochemical attachment of fluorobutyl moieties on a diamond (110)-oriented surface: A multiple internal reflection infrared spectroscopic (MIRIRS) investigation SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ALKYL IODIDES; FLUORINATION; DESORPTION; HYDROGEN; BEAMS; FILMS; BAND; CF3I AB The chemistry of perfluorobutyl iodide (C4F9I) on I-I-free and II-terminated diamond (110)-oriented surfaces was investigated using multiple internal reflection infrared spectroscopy (MIRIRS). C4F9I physisorbed to form multilayers at 90 K for both surface terminations. The physisorbed C4F9I desorbed from the surface when heated above 200 K and the starting surface was regenerated. The electronic structure and vibrational spectra of the perfluorobutyl group were calculated for perfluorobutyl chloride and perfluorobutyl bromide and the MIRIRS of the physisorbed multilayer agreed well with calculated infrared spectra. After exposing the C4F9I multilayer at 90 K to UV radiation for 30 min and subsequently heating thp surface above 200 K characteristic vibrational features of the perfluorobutyl group were observed between 1138 and 1355 cm(-1) In a series of annealing experiments, these modes persisted on the surface up to 600 K and completely disappeared by 700 K. The same results were observed on both the H-free and H-terminated surfaces. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Russell, JN (reprint author), USN, Res Lab, Div Chem, Code 6170, Washington, DC 20375 USA. EM russell2@ccf.nrl.navy.mil RI Butler, James/B-7965-2008; Russell, John/A-3621-2009 OI Butler, James/0000-0002-4794-7176; NR 36 TC 33 Z9 34 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD NOV 12 PY 1998 VL 102 IS 46 BP 9290 EP 9296 DI 10.1021/jp982769s PG 7 WC Chemistry, Physical SC Chemistry GA 141MD UT WOS:000077147000014 ER PT J AU Millett, MG Nelson, ME AF Millett, MG Nelson, ME TI Weight and counting efficiency optimization in a moderated neutron detection system SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE neutron detector; fission source; computer modeling; experimental data; arms control AB This paper describes a technique in which a polyethylene moderated neutron detector was designed in order to have the optimum combination of maximum counting efficiency and minimum weight. Such a detector would be of use in arms control, counter proliferation or treaty verification applications, in which measurement time and system portability are important considerations. In such applications, the neutron source may be a spontaneous fissioning isotope such as Pu-240. After consideration of many different neutron detection schemes, the paper concludes that the best detection scheme for this problem would be a system which utilizes He-3 gas filled detectors surrounded by a moderator material. The "moderator weight efficiency" concept was developed as the basis for comparisons of different moderators and geometries. The MCNP neutron transport code was then used to evaluate moderator efficiencies for these different systems. The moderators considered by the paper included light water, heavy water, graphite, and polyethylene. The moderator geometries considered were a variety of shapes between (and including) planar and cylindrical. The paper describes an optimized system, which was found to have a combination of maximum performance and minimum moderator and system weight. The optimized detector was then fabricated and experimentally tested against another system, one which is currently employed in the INF treaty between Russia and the United States, Results are presented which show that the ''optimized" system has higher counts per unit moderator (and system) weight than the TNF comparison system. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Maryland, USN Acad, College Pk, MD 20742 USA. RP Millett, MG (reprint author), USN, DSWA Detachement, Washington, DC 20350 USA. NR 10 TC 5 Z9 5 U1 1 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 NOV 11 PY 1998 VL 417 IS 2-3 BP 332 EP 341 DI 10.1016/S0168-9002(98)00685-8 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 138FG UT WOS:000076960200013 ER PT J AU Piner, BG Kingham, KA AF Piner, BG Kingham, KA TI Geodetic VLBI observations of EGRET blazars SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : jets; quasars : individual (0202+149, CTA 26, 1156+295, 1606+106); radio continuum : galaxies ID ACTIVE GALACTIC NUCLEI; EXTRAGALACTIC RADIO-SOURCES; FREQUENCY VARIABLE SOURCES; REFERENCE FRAME SOURCES; GAMMA-RAY EMISSION; MILLIARCSECOND STRUCTURE; SUPERLUMINAL MOTION; BL-LACERTAE; BRIGHTNESS TEMPERATURES; VLA OBSERVATIONS AB We present VLBI observations of the EGRET quasars 0202+149, CTA 26, and 1606+106, as well as additional analysis of VLBI observations of 1156+295 presented in a previous letter. We have produced 8 and 2 GHz VLBI images at II epochs, 8 epochs, and 12 epochs, spanning the years 1989-1996, of 0202+149, CTA 26, and 1606+106, respectively. The VLBI data have been taken from the Washington VLBI correlator's geodetic database. We have measured the apparent velocities of the jet components and find that CTA 26 and 1606+106 are superluminal sources, with average apparent speeds of 8.9 and 2.9 h(-1) c, respectively (H-0 = 100 h km s(-1) Mpc(-1), q(0) = 0.5). The components in 0202+149 are stationary, and we identify this source as a compact F double. These sources all have apparently bent jets, and we detected nonradial motion of components in CTA 26 and 1156 + 295. We have not yet detected any components emerging subsequent to the gamma-ray flares in CTA 26, 1156+295, and 1606+106, and we derive lower limits on the ejection times of any such components. The misalignment angle distribution of the EGRET sources is compared to the distribution for blazars as a whole, and we find that EGRET sources belong preferentially to neither the aligned nor the misaligned population. We also compare the average values for the apparent velocities and Doppler beaming factors for the EGRET and non-EGRET blazars, and find no significant differences. We thus find no indication, within the measurement errors, that EGRET blazars are any more strongly beamed than their counterparts that have not been detected in gamma-rays. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. USN Observ, Earth Orientat Dept, Washington, DC 20392 USA. RP Piner, BG (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,M-S 238-332, Pasadena, CA 91109 USA. NR 75 TC 19 Z9 19 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1998 VL 507 IS 2 BP 706 EP 725 DI 10.1086/306346 PN 1 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LU UT WOS:000077779700012 ER PT J AU Feldman, U AF Feldman, U TI On the unresolved fine structures of the solar atmosphere. III. Elemental abundances consideration SO ASTROPHYSICAL JOURNAL LA English DT Article DE sun : abundances; sun : atmosphere; sun : corona ID EXTREME-ULTRAVIOLET SPECTRUM; REGIONS AB Results from high-quality solar upper atmosphere observations in the 10(4)-10(6) K range contradict predictions made by models that assume that a single class of structures stretching throughout the entire temperature domain, from the cold chromosphere to the hot corona, is responsible for ail the radiation we see. As a result, I proposed that new types of structures-the unresolved fine structures (UFSs)-are responsible for most of the detected emission in the 3 x 10(6) less than or equal to T-e less than or equal to 8 x 10(6) K. In a recent paper Wikstol, Judge, & Hansteen challenged the presence of UFSs by claiming that the interpretation of the data in terms of UFSs is not unique and is likely to be incorrect in the presence of plasmas with unresolved dynamics. Further, they claim that most or all of the evidence that was brought in support of the UFSs is amenable to a different, equally reasonable interpretation in which the transition region emission is at all times formed in the time-varying thermal interface between the corona and chromosphere. In this paper I discuss some of the assertions made by Wikstol and collaborators. I also bring evidence from elemental abundance studies that would be difficult to support with the Wikstol model. In contrast, the existence of UFSs is not contradicted by any of the new observations. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Feldman, U (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 28 TC 13 Z9 13 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1998 VL 507 IS 2 BP 974 EP 977 DI 10.1086/306361 PN 1 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LU UT WOS:000077779700032 ER PT J AU Larraza, A Denardo, B AF Larraza, A Denardo, B TI An acoustic Casimir effect SO PHYSICS LETTERS A LA English DT Article ID FORCE AB Theoretical and experimental results are presented for the force law between two rigid, parallel plates due to the radiation pressure of band-limited acoustic noise. Excellent agreement is shown between theory and experiment. While these results constitute an acoustic analog for the Casimir effect, an important difference is that band-limited noise can cause the force to be attractive or repulsive as a function of the distance of separation of the plates. Applications of the acoustic Casimir effect to background noise transduction and non-resonant acoustic levitation are suggested. (C) 1998 Elsevier Science B.V. C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. RP Larraza, A (reprint author), USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. NR 9 TC 24 Z9 24 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD NOV 9 PY 1998 VL 248 IS 2-4 BP 151 EP 155 DI 10.1016/S0375-9601(98)00652-5 PG 5 WC Physics, Multidisciplinary SC Physics GA 135KA UT WOS:000076799800010 ER PT J AU Parks, AD Cullin, DW Stoudt, DC AF Parks, AD Cullin, DW Stoudt, DC TI Observation and measurement of an optical Aharonov-Albert-Vaidman effect SO PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article DE AAV effect; weak values; weak energy; postselection measurements ID QUANTUM-MECHANICS; WEAK MEASUREMENT; COMPONENT; STATES; SPIN AB The notion of the weak value of a quantum mechanical observable has recently been introduced by Aharonov ct al., hereafter referred to as AAV. Their analysis led to the controversial result that the weak values for an observable can lie well outside its associated eigenvalue spectrum. We have performed an experiment similar to one proposed by Knight ct al. and demonstrated that weak values can be observed and that they exhibit the properties described by AAV within the regime of validity defined by Duck et al. It is shown that these properties are produced by interference phenomena that result from the loss of 'welcher Weg' information. We have also identified an intrinsic 'weak energy' which appears in the equation of motion for the weak value of an observable and have shown that it can be non-vanishing only for systems which are both preselected and postselected. It is noted that such a 'weak spin-rotation coupling energy' can be associated with our experiment and that it is manifested in our experimental data. We suggest that preselection and postselection measurement techniques could be useful for the creation and study of physical phenomena that might be otherwise unobservable. C1 USN, Ctr Surface Warfare, Quantum Proc Grp, Syst Res & Technol Dept, Dahlgren, VA 22448 USA. RP Parks, AD (reprint author), USN, Ctr Surface Warfare, Quantum Proc Grp, Syst Res & Technol Dept, Dahlgren, VA 22448 USA. NR 15 TC 54 Z9 54 U1 0 U2 2 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-5021 EI 1471-2946 J9 P ROY SOC A-MATH PHY JI Proc. R. Soc. A-Math. Phys. Eng. Sci. PD NOV 8 PY 1998 VL 454 IS 1979 BP 2997 EP 3008 PG 12 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 140LN UT WOS:000077088900008 ER PT J AU Bermudez, VM AF Bermudez, VM TI Study of the growth of thin Mg films on wurtzite GaN surfaces SO SURFACE SCIENCE LA English DT Article DE epitaxy; gallium nitride; growth; interface states; magnesium; metal-semiconductor interfaces ID RAY PHOTOEMISSION SPECTROSCOPY; GAN(0001)-(1X1) SURFACE; MG(0001) SURFACE; NITRIDE; METALS; CHEMISORPTION; MORPHOLOGY; MAGNESIUM; SAPPHIRE; SPECTRA AB The growth, structure and electronic properties of thin (less than or equal to 20 Angstrom thick) Mg films on clean, n-type wurtzite GaN have been studied using Auger, photoemission and electron-energy-loss spectroscopies and low-energy electron diffraction. Epitaxial growth occurs near 300 K leading to a (1 x 1)-ordered metal layer. Site exchange between Mg and Ga releases free Ga, which remains near the interface, and incorporates Mg into the GaN near the interface. Deposition of less than one monolayer of Mg moves the Fermi level similar to 0.60 eV farther down into the gap, from the initial position of 2.60 eV above the valence band maximum, where it remains essentially fixed with increasing Mg coverage. Annealing leads to desorption of metallic Mg which, for a thin film, is essentially complete at similar to 520 K. There is no indication of extensive intermixing of either Ga or N with the Mg. A residue of Ga and Mg adatoms or small non-metallic clusters, remaining after desorption of the metal, persists to at least 620 K. Desorption of metallic Mg has little or no effect on the Fermi-level position which, therefore, is determined mainly by trapping of electrons by accepters that result from Mg incorporation into the surface, rather than by Schottky-barrier formation. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Bermudez, VM (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM bermudez@estd.nrl.navy.mil.us NR 51 TC 14 Z9 14 U1 2 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD NOV 8 PY 1998 VL 417 IS 1 BP 30 EP 40 DI 10.1016/S0039-6028(98)00659-1 PG 11 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 140QY UT WOS:000077100900008 ER PT J AU Ogale, SB Ghosh, K Pai, SP Robson, M Li, E Jin, I Greene, RL Ramesh, R Venkatesan, T Johnson, M AF Ogale, SB Ghosh, K Pai, SP Robson, M Li, E Jin, I Greene, RL Ramesh, R Venkatesan, T Johnson, M TI Fe3O4/SrTiO3/La0.7Sr0.3MnO3 heterostructure: growth and properties. SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article; Proceedings Paper CT 4th International Workshop on Oxide Electronics CY DEC 08-09, 1997 CL UNIV MARYLAND, COLLEGE PK, MARYLAND SP DARPA, Univ Maryland, NSF-MRSEC, Univ Maryland, Ctr Superconduct Res HO UNIV MARYLAND DE heterostructure; X-ray diffraction; magnetoresistance ID LARGE POSITIVE MAGNETORESISTANCE; TRANSPORT AB Fe3O4/SrTiO3/La0.7Sr0.3MnO3 (LSMO) epitaxial heterostructures were grown by pulsed laser deposition on LaAlO3(001) substrates. The high structural quality of the heterostructures was established by X-ray diffraction measurements. The vertical (current perpendicular to plane-CPP) transport in the heterostructure, without and with the magnetic field applied in and perpendicular to the film plane was studied as a function of temperature. The magnetization behavior was also examined. Application of the magnetic field in the him plane is found to yield a large positive magnetoresistance (MR) while a perpendicular held is found to lead to a negative MR at low fields followed by a large positive MR at higher fields. The observed MR features do not show any obvious correlation with the hysterisis behavior of the ferromagnetic bilayers. A possible explanation of these results is given in terms of the relative differences in the majority and minority spin bands of the two ferromagnetic layers and the field induced modifications of domain structures therein. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Maryland, MRSEC, NSF, College Pk, MD 20742 USA. Univ Maryland, Dept Phys, Ctr Superconduct Res, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. RP Johnson, M (reprint author), Univ Maryland, MRSEC, NSF, College Pk, MD 20742 USA. EM mjbooj@anvil.nrl.navy.mil RI Venkatesan, Thirumalai/E-1667-2013 NR 17 TC 16 Z9 16 U1 2 U2 13 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5107 J9 MAT SCI ENG B-SOLID JI Mater. Sci. Eng. B-Solid State Mater. Adv. Technol. PD NOV 6 PY 1998 VL 56 IS 2-3 BP 134 EP 139 DI 10.1016/S0921-5107(98)00216-5 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 150GK UT WOS:000077655700011 ER PT J AU Gardner, MJ Tettelin, H Carucci, DJ Cummings, LM Aravind, L Koonin, EV Shallom, S Mason, T Yu, K Fujii, C Pederson, J Shen, K Jing, JP Aston, C Lai, ZW Schwartz, DC Pertea, M Salzberg, S Zhou, LX Sutton, GG Clayton, R White, O Smith, HO Fraser, CM Adams, MD Venter, JC Hoffman, SL AF Gardner, MJ Tettelin, H Carucci, DJ Cummings, LM Aravind, L Koonin, EV Shallom, S Mason, T Yu, K Fujii, C Pederson, J Shen, K Jing, JP Aston, C Lai, ZW Schwartz, DC Pertea, M Salzberg, S Zhou, LX Sutton, GG Clayton, R White, O Smith, HO Fraser, CM Adams, MD Venter, JC Hoffman, SL TI Chromosome 2 sequence of the human malaria parasite Plasmodium falciparum SO SCIENCE LA English DT Article ID COMPLETE GENOME SEQUENCE; ERYTHROCYTE SURFACE-ANTIGEN; BLOOD STAGE ANTIGEN; MOLECULAR-CLONING; MEMBRANE PROTEIN; GENETIC-ANALYSIS; SERINE-STRETCH; REPETITIVE DNA; SERA GENE; DOMAINS AB Chromosome 2 of Plasmodium falciparum was sequenced; this sequence contains 947,103 base pairs and encodes 210 predicted genes. In comparison with the Saccharomyces cerevisiae genome, chromosome 2 has a lower gene density, introns are more frequent, and proteins are markedly enriched in nonglobular domains. A family of surface proteins, rifins, that may play a role in antigenic variation was identified. The complete sequencing of chromosome 2 has shown that sequencing of the A + T-rich P. falciparum genome is technically feasible. C1 USN, Med Res Inst, Malari Program, Rockville, MD 20852 USA. Inst Genome Res, Rockville, MD 20850 USA. Texas A&M Univ, Dept Biol, College Stn, TX USA. Natl Lib Med, Natl Ctr Biotechnol Informat, NIH, Bethesda, MD 20894 USA. NYU, Dept Chem, Lab Biomol Imaging, New York, NY 10003 USA. Johns Hopkins Univ, Dept Comp Sci, Baltimore, MD 21218 USA. Inst Genom Res, Rockville, MD 20850 USA. Johns Hopkins Univ, Dept Comp Sci, Baltimore, MD 21218 USA. RP Hoffman, SL (reprint author), USN, Med Res Inst, Malari Program, 12300 Washington Ave, Rockville, MD 20852 USA. RI Salzberg, Steven/F-6162-2011 OI Salzberg, Steven/0000-0002-8859-7432 FU NIAID NIH HHS [R01 AI40125-01] NR 73 TC 383 Z9 403 U1 0 U2 6 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD NOV 6 PY 1998 VL 282 IS 5391 BP 1126 EP 1132 DI 10.1126/science.282.5391.1126 PG 7 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 136YY UT WOS:000076887700051 PM 9804551 ER PT J AU Sitzmann, ME Kenar, JA Trivedi, NJ AF Sitzmann, ME Kenar, JA Trivedi, NJ TI Facile formation of N-alkyl-oxazolidin-2-ones from N-alkyl-nitroxyethylamines and carbonate anion in biphasic media. SO TETRAHEDRON LETTERS LA English DT Article AB Nitration of N-alkyl ethanolamines (1) followed by treatment of their corresponding N-alkyl-N-(2-nitroxyethyl)amine salts (2) in a biphasic CH2Cl2/aqueous Na2CO3 or NaHCO3 mixture at 25 degrees C gives N-alkyl-oxazolidin-2-ones (3). This represents a new method that allows the preparation of oxazolidinones at ambient temperature with the use of aqueous carbonate. Published by Elsevier Science Ltd. C1 USN, Ctr Surface Warfare, Indian Head Div, Indian Head, MD 20640 USA. RP Sitzmann, ME (reprint author), USN, Ctr Surface Warfare, Indian Head Div, Indian Head, MD 20640 USA. NR 2 TC 5 Z9 5 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4039 J9 TETRAHEDRON LETT JI Tetrahedron Lett. PD NOV 5 PY 1998 VL 39 IS 45 BP 8211 EP 8212 DI 10.1016/S0040-4039(98)01877-2 PG 2 WC Chemistry, Organic SC Chemistry GA 130MP UT WOS:000076524100007 ER PT J AU Roberts, MJ Lindsay, GA Herman, WN Wynne, KJ AF Roberts, MJ Lindsay, GA Herman, WN Wynne, KJ TI Thermally stable nonlinear optical films by alternating polyelectrolyte deposition on hydrophobic substrates SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID POLYMERS C1 USN, Air Warfare Ctr, Weap Div, Chem & Mat Branch, China Lake, CA 93555 USA. USN, Air Warfare Ctr, Div Aircraft, Electroopt Sensors Branch, Patuxent River, MD 20657 USA. Off Naval Res, Arlington, VA 22217 USA. RP Roberts, MJ (reprint author), USN, Air Warfare Ctr, Weap Div, Chem & Mat Branch, Code 4B2200D,1 Adm Circle, China Lake, CA 93555 USA. NR 13 TC 69 Z9 70 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD NOV 4 PY 1998 VL 120 IS 43 BP 11202 EP 11203 DI 10.1021/ja9822613 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 136JE UT WOS:000076855000030 ER PT J AU Miller, JB AF Miller, JB TI NMR imaging of materials SO PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY LA English DT Review ID NUCLEAR-MAGNETIC-RESONANCE; SOLID-STATE NMR; HIGH-RESOLUTION NMR; BELOUSOV-ZHABOTINSKY REACTION; RADIATION-DOSE DISTRIBUTIONS; DOUBLE-QUANTUM COHERENCE; ACOUSTIC STRAIN WAVES; MULTIPLE PULSE NMR; FIELD-GRADIENT NMR; ROTATING-FRAME C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Miller, JB (reprint author), USN, Res Lab, Div Chem, Code 6120, Washington, DC 20375 USA. EM miller5@ccf.nrl.navy.mil NR 280 TC 32 Z9 32 U1 1 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0079-6565 J9 PROG NUCL MAG RES SP JI Prog. Nucl. Magn. Reson. Spectrosc. PD NOV 2 PY 1998 VL 33 BP 273 EP 308 DI 10.1016/S0079-6565(98)00024-7 PN 3-4 PG 36 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Chemistry; Physics; Spectroscopy GA 152YN UT WOS:000077805700003 ER PT J AU Burgher, SW McGuirk, TD AF Burgher, SW McGuirk, TD TI Subcutaneous buffered lidocaine for intravenous cannulation: Is there a role in emergency medicine? SO ACADEMIC EMERGENCY MEDICINE LA English DT Article DE catheterization, peripheral; anesthesia, local lidocaine ID VENOUS CANNULATION; SKIN INFILTRATION; ETHYL CHLORIDE; PAIN; ANESTHESIA; LIGNOCAINE; CHILDREN; ANALGESIA; EFFICACY; ACCESS AB Objective: To prospectively evaluate whether subcutaneous buffered lidocaine (SQBL) significantly reduces the pain or adversely affects the success rate of IV cannulation (NC) in adult ED patients. Methods: A convenience sample of patients greater than or equal to 18 years old requiring NC in a regional military ED were prospectively randomized to receive SQBL, SQ normal saline with 0.9% benzyl alcohol (SQNS), or no pretreatment (NPTx), prior to IVC with an 18-gauge angiocatheter. SQ infiltration was accomplished using a 27-gauge insulin syringe. Investigators and patients were blinded to SQBL and SQNS in the pretreatment groups. The number of attempts at NC was recorded for each patient. A 100-mm visual analog pain scale (VAPS) was used to record pain scores for both SQ infiltration and NC. Comparisons of the mean numbers of attempts to achieve NC and of the VAPS scores were accomplished by analysis of variance followed by Duncan's multiple range test if significance was found. Results: A total of 103 patients (SQBL-34, SQNS-30, and NPTx-39) were enrolled between November 15, 1996, and June 13, 1997. There were no significant differences among the groups in either the mean number of attempts (SQBL = 1.35, 95% CI +/- 0.260; SQNS = 1.13, 95% CI +/- 0.124; and NPTx = 1.28, 95% CI +/- 0.203) (p = 0.367) or the success rate on the first attempt (SQBL = 79.4%, SQNS = 86.7%, NPTx = 79.5%) (p = 0.533). The median VAPS score of NC without pretreatment (21 mm, 95% CI +/- 7.97) was greater than that for SQBL infiltration alone (10 mm, 95% CI +/- 9.11), SQNS infiltration alone (9 mm, 95% CI +/- 7.37), and NC after SQBL (6 mm, 95% CI +/- 9.18) (p < 0.009 for each group). SQNS infiltration had no significant effect on the VAPS score of subsequent IVC (20 mm, 95% CI + 10.5) compared with NC without pretreatment (21 mm). Conclusions: SQBL significantly reduced the pain, while not adversely affecting the success rate, of NC in adult patients in the ED. C1 Naval Med Ctr Portsmouth, Dept Emergency Med, Portsmouth, VA 23708 USA. RP Burgher, SW (reprint author), Naval Med Ctr Portsmouth, Dept Emergency Med, Bldg 215,620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 26 TC 13 Z9 13 U1 0 U2 0 PU HANLEY & BELFUS INC PI PHILADELPHIA PA 210 S 13TH ST, PHILADELPHIA, PA 19107 USA SN 1069-6563 J9 ACAD EMERG MED JI Acad. Emerg. Med. PD NOV PY 1998 VL 5 IS 11 BP 1057 EP 1063 PG 7 WC Emergency Medicine SC Emergency Medicine GA 137AG UT WOS:000076890800004 PM 9835466 ER PT J AU Kimmel, EC Reboulet, JE AF Kimmel, EC Reboulet, JE TI Calculation of exposure chamber leak rate with thermal correction: A measure of chamber integrity SO AMERICAN INDUSTRIAL HYGIENE ASSOCIATION JOURNAL LA English DT Article DE exposure chamber; leak rate; thermal effects ID BAFFLED RECTANGULAR CHAMBERS; INTERNAL HEAT-SOURCES; MIXED CONVECTION AB A method for assessing inhalation exposure chamber integrity by calculation of leak rate was modified to account for temporal changes of temperature in the chamber. In a well-sealed chamber, accounting for thermal effect brought observed leak rates into better agreement with predicted values. Mean estimates of chamber leak rate without thermal correction ranged from 2.9 to 40.6 cm(3)/min whereas those with thermal correction ranged from 9.6 to 14.3 cm(3)/min. The average change in estimate of chamber leak rate brought about by correcting for thermal effect was 16.8 cm(3)/min per K change of temperature in the chamber. Accounting for thermal effect reduced the coefficient of variation for repeated estimates (n = 10) of chamber leak rate from 65 to 15%. The use of temperature-corrected calculation of chamber leak rate minimizes thermal artifact thereby improving decisions about chamber operation based on assessment of chamber integrity. C1 Natl Naval Med Ctr, Geoctr Inc, Detachment Toxicol & Triserv Toxicol Consortium, NMRI TD, Wright Patterson AFB, OH 45433 USA. RP Kimmel, EC (reprint author), Natl Naval Med Ctr, Geoctr Inc, Detachment Toxicol & Triserv Toxicol Consortium, NMRI TD, Bldg 433,Area B,2612 5th St, Wright Patterson AFB, OH 45433 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER INDUSTRIAL HYGIENE ASSOC PI FAIRFAX PA 2700 PROSPERITY AVE #250, FAIRFAX, VA 22031-4307 USA SN 0002-8894 J9 AM IND HYG ASSOC J JI Am. Ind. Hyg. Assoc. J. PD NOV PY 1998 VL 59 IS 11 BP 779 EP 784 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA 142EG UT WOS:000077186500006 PM 9830085 ER PT J AU Mazzella, FM Kowal-Vern, A Shrit, MA Wibowo, AL Rector, JT Cotelingam, JD Collier, J Mikhael, A Cualing, H Schumacher, HR AF Mazzella, FM Kowal-Vern, A Shrit, MA Wibowo, AL Rector, JT Cotelingam, JD Collier, J Mikhael, A Cualing, H Schumacher, HR TI Acute erythroleukemia - Evaluation of 48 cases with reference to classification, cell proliferation, cytogenetics, and prognosis SO AMERICAN JOURNAL OF CLINICAL PATHOLOGY LA English DT Article DE erythroleukemia; M6a (FAB-MG); M6b (pure erythroleukemia); cell proliferation ID ACUTE MYELOID-LEUKEMIA; HUMAN CANCER; CHROMOSOMES; CAUSATION AB We evaluated 48 archival cases of acute erythroleukemia and divided them into 3 groups: M6a, corresponding to the traditional French-American-British M6 category; M6b, which is pure erythroleukemia; and M6c, in which myeloblasts and pronormoblasts each account for more than 30% of cells by the French-American-British exclusion criteria. No significant differences were noted among the subtypes for ratio of males to females; age; or exposure to toxins, alcohol, or both. However, compared with the patients in the M6a group, patients in the M6b and M6c groups demonstrated a statistically significant increase in cytogenetic aberrations, proliferation markers (proliferating cell nuclear antigen and Ki67), and ringed (type III) sideroblasts. Marked survival differences were noted between the M6a (30.1 +/- 29.5 months) and M6b (3.15 +/- 4.2 months) groups, with patients in the M6c group demonstrating an intermediate prognosis (10.5 +/- 12.7 months). Chemotherapeutic regimens induced remission in all treated patients in the M6a and M6c groups but did not appear to affect the M6b group. However; the patients in the M6c group remained in remission for a significantly shorter period of time than did patients in the M6a group. Overall, survival appeared to depend on the ratio of pronormoblasts to myeloblasts at diagnosis and demonstrated a rapid decline with increasing pronormoblast and decreasing myeloblast counts. We must, therefore, devise chemotherapeutic regimens that target both blastic components of this disease. C1 Univ Cincinnati, Med Ctr, Dept Pathol & Lab Med, Cincinnati, OH 45267 USA. Loyola Univ, Ctr Med, Dept Pathol & Lab Med, Maywood, IL USA. Miami Valley Hosp, Dept Pathol, Dayton, OH USA. USN, Natl Med Ctr, Dept Navy, Bethesda, MD USA. RP Mazzella, FM (reprint author), Guthrie Clin, Dept Pathol & Lab Med, Guthrie Sq, Sayre, PA 18840 USA. NR 20 TC 38 Z9 42 U1 0 U2 0 PU AMER SOC CLIN PATHOLOGISTS PI CHICAGO PA 2100 W HARRISON ST, CHICAGO, IL 60612 USA SN 0002-9173 J9 AM J CLIN PATHOL JI Am. J. Clin. Pathol. PD NOV PY 1998 VL 110 IS 5 BP 590 EP 598 PG 9 WC Pathology SC Pathology GA 131XR UT WOS:000076601000004 PM 9802343 ER PT J AU Duntemann, TJ AF Duntemann, TJ TI Clinical and economic outcomes in endoscopy research: Footsteps down the path SO AMERICAN JOURNAL OF GASTROENTEROLOGY LA English DT Editorial Material ID UPPER GASTROINTESTINAL HEMORRHAGE; BLEEDING PEPTIC-ULCER; COST; INJECTION; THERAPY; PROBE C1 USN, Med Ctr, Div Gastroenterol, Portsmouth, VA 23708 USA. RP Duntemann, TJ (reprint author), USN, Med Ctr, Div Gastroenterol, Portsmouth, VA 23708 USA. NR 15 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0002-9270 J9 AM J GASTROENTEROL JI Am. J. Gastroenterol. PD NOV PY 1998 VL 93 IS 11 BP 2009 EP 2011 DI 10.1111/j.1572-0241.1998.02009.x PG 3 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 136JZ UT WOS:000076856800001 PM 9820365 ER PT J AU Tanzer, DJ Isfahani, A Schallhorn, SC LaBree, LD McDonnell, PJ AF Tanzer, DJ Isfahani, A Schallhorn, SC LaBree, LD McDonnell, PJ TI Photorefractive keratectomy in African Americans including those with known dermatologic keloid formation SO AMERICAN JOURNAL OF OPHTHALMOLOGY LA English DT Article; Proceedings Paper CT Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY MAY 10-15, 1998 CL FT LAUDERDALE, FLORIDA SP Assoc Res Vis & Ophthalmol ID CORNEAL AB PURPOSE: To report the outcome of photorefractive keratectomy in African Americans, including those with a known history of dermatologic keloid formation. METHODS: A retrospective analysis of African American patients who had photorefractive keratectomy at either of our institutions was undertaken to identify all patients who were at least 3 months status post refractive surgery. The presence or absence of a history of keloid formation, as well as preoperative and postoperative measurements of uncorrected visual acuity, best-corrected visual acuity, manifest refraction, and the presence and magnitude of any postoperative corneal haze were analyzed. RESULTS: Twelve patients (19 eyes) met the in elusion criteria and three of these patients (six eyes) had a history of keloid formation. Mean uncorrected visual acuity a SD for the entire study group improved from 20/369 +/- 20/270 preoperatively to 20/19.4 +/- 20/7.1 postoperatively (average follow-up, 13.8 months). All eyes had postoperative uncorrected visual acuity of 20/40 or better; 14 (74%) achieved 20/20 or better. Mean best spectacle corrected visual acuity went from 20/14.8 +/- 20/2.8 preoperatively to 20/15.5 +/- 20/3.2 postoperatively (not statistically significant). Mean manifest spherical equivalent was -4.9 +/- 3.4 diopters preoperatively and +0.03 +/- 0.55 diopters postoperatively. Eight eyes (42%) had trace to 1+ corneal haze following photorefractive surgery. A comparison of postoperative uncorrected and best corrected visual acuities of known keloid formers with nonkeloid formers revealed no significant statistical difference. CONCLUSIONS: African Americans may have excellent visual outcomes following photorefractive keratectomy. History of keloid formation does not appear to have an adverse effect on the outcome. These results question whether known dermatologic keloid formation should be contraindication to photorefractive keratectomy. (Am J Ophthalmol 1998;126:625-629, (C) 1998 by Elsevier Science Inc. All rights reserved.). C1 Univ So Calif, Doheny Eye Inst, Dept Ophthalmol, Los Angeles, CA 90033 USA. USN, Med Ctr, San Diego, CA 92152 USA. RP McDonnell, PJ (reprint author), Univ So Calif, Doheny Eye Inst, Dept Ophthalmol, 1450 San Pablo St, Los Angeles, CA 90033 USA. FU NEI NIH HHS [EY03040] NR 21 TC 11 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0002-9394 J9 AM J OPHTHALMOL JI Am. J. Ophthalmol. PD NOV PY 1998 VL 126 IS 5 BP 625 EP 629 DI 10.1016/S0002-9394(98)00204-9 PG 5 WC Ophthalmology SC Ophthalmology GA 136BQ UT WOS:000076838300001 PM 9822225 ER PT J AU Larsen, I Little, B Nealson, KH Ray, R Stone, A Tian, JH AF Larsen, I Little, B Nealson, KH Ray, R Stone, A Tian, JH TI Manganite reduction by Shewanella putrefaciens MR-4 SO AMERICAN MINERALOGIST LA English DT Article ID MANGANESE(IV) OXIDES; MICROBIAL REDUCTION; DISSOLUTION; GROWTH; ORGANICS; SULFUR AB Previous studies have documented dissimilatory growth of bacteria on solid Mn4+ oxide, but Mn3+ oxides have not been previously studied; here we have demonstrated for the first time the bacterial reduction of manganite. Strain MR-4 of Shewanella putrefaciens was able to grow on and rapidly reduce insoluble needle-shaped crystals of synthetic manganite (MnOOH), converting them to soluble Mn2+ in the process. The rate of Mn3+ reduction was optimal at pH of 7.0 and 26 degrees C consistent with an enzymatic reaction. In addition the rates of reduction were in proportion to the amount of manganite added, but nearly independent of the cell concentration present (e.g., cell number had only a small effect on the rate of Mn3+ reduction at early stages of growth) suggesting that surface properties were dictating the rates of metal reduction. This thesis was supported by major differences in reduction rates when Mn oxides of different surface areas were studied. Removal of the carbon source (formate or lactate) or addition of metabolic inhibitors reduced the rate of metal reduction. No Mn3+ reduction was observed when the samples were oxygenated, nor when the cells were separated from the Mn3+ oxide by a dialysis membrane. Environmental scanning electron microscopy (ESEM) images showed close contact of the cells with the needle-shaped crystals during early stages of reduction. In later stages, the closely associated cells were coated with a layer of extracellular polymeric material that obscured the cells when viewed by ESEM. When manganite crystals were dried and gold coated, and viewed by standard scanning electron microscopy (SEM), abundant bacteria could be seen on the surface of the metal oxide in a thin biofilm-like layer. The layer of extracellular polymer is a new finding, and neither the composition, function, nor importance in the manganese reduction process have been elucidated. C1 Univ Wisconsin, Ctr Great Lakes Studies, Milwaukee, WI 53204 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Johns Hopkins Univ, Dept Geog & Environm Engn, Baltimore, MD 21218 USA. RP Larsen, I (reprint author), Univ Wisconsin, Ctr Great Lakes Studies, 600 E Greenfield Ave, Milwaukee, WI 53204 USA. RI Stone, Alan/A-2569-2010 OI Stone, Alan/0000-0002-3660-1129 NR 17 TC 16 Z9 16 U1 0 U2 9 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1015 EIGHTEENTH ST, NW SUITE 601, WASHINGTON, DC 20036 USA SN 0003-004X J9 AM MINERAL JI Am. Miner. PD NOV-DEC PY 1998 VL 83 IS 11-12 BP 1564 EP 1572 PN 2 PG 9 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 145YE UT WOS:000077399200017 ER PT J AU Lucke, RL AF Lucke, RL TI Deriving the Coltman correction for transforming the bar transfer function to the optical transfer function (or the contrast transfer function to the modulation transfer function) SO APPLIED OPTICS LA English DT Article AB The Coltman series for obtaining the optical transfer function from measurements of the bar transfer function is mathematically derived. The bar transfer function rather than the contrast transfer function is defined so that the relation remains valid when an image exhibits phase reversal. (C) 1998 Optical Society of America OCIS codes: 110.0110, 110.4100, 110.4850. C1 USN, Res Lab, Washington, DC 20375 USA. RP Lucke, RL (reprint author), USN, Res Lab, Code 7227, Washington, DC 20375 USA. NR 4 TC 7 Z9 7 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD NOV 1 PY 1998 VL 37 IS 31 BP 7248 EP 7252 DI 10.1364/AO.37.007248 PG 5 WC Optics SC Optics GA 134VJ UT WOS:000076764100013 PM 18301554 ER PT J AU Hummel, CA Mozurkewich, D Armstrong, JT Hajian, AR Elias, NM Hutter, DJ AF Hummel, CA Mozurkewich, D Armstrong, JT Hajian, AR Elias, NM Hutter, DJ TI Navy Prototype Optical Interferometer observations of the double stars Mizar A and Matar SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : spectroscopic; techniques : interferometric ID EFFECTIVE TEMPERATURES; BOLOMETRIC CORRECTIONS; TRANSFORMATIONS; DIAGRAMS; BINARIES; COLORS; SCALE AB We present a detailed analysis of two spectroscopic binaries based on new observations obtained with the Navy Prototype Optical Interferometer (NPOI). While the data calibration needs refinement, first results show the impressive potential of NPOI, both in terms of speed and precision, for imaging and modeling the orbits of spectroscopic binaries. We determine the orbital parameters of Mizar A (zeta(1) Ursae Majoris) and Matar (eta Pegasi), and derive masses and luminosities using published radial velocities and Hipparcos trigonometric parallaxes. The results on Mizar A are compared to earlier work done with the Mark III interferometer, while data from this instrument were combined with NPOI data in the Matar analysis. C1 USN Observ, Astrometry Dept, Washington, DC 20392 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Hummel, CA (reprint author), USN Observ, Astrometry Dept, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. EM cah@fornax.usno.navy.mil; mozurk@rsd.nrl.navy.mil; tarmstr@fornax.usno.navy.mil; hajian@fornax.usno.navy.mil; nme@sextans.lowell.edu; djh@forrnax.usno.navy.mil NR 26 TC 87 Z9 88 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 1998 VL 116 IS 5 BP 2536 EP 2548 DI 10.1086/300602 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 134UZ UT WOS:000076763200039 ER PT J AU Platais, I Girard, TM Kozhurina-Platais, V van Altena, WF Lopez, CE Mendez, RA Ma, WZ Yang, TG MacGillivray, HT Yentis, DJ AF Platais, I Girard, TM Kozhurina-Platais, V van Altena, WF Lopez, CE Mendez, RA Ma, WZ Yang, TG MacGillivray, HT Yentis, DJ TI The Southern Proper Motion program. II. A catalog at the South Galactic pole SO ASTRONOMICAL JOURNAL LA English DT Article DE astrometry; catalogs; stars : kinematics ID CLUSTERS; NGC-3680; AGE AB We describe the Yale/San Juan Southern Proper Motion (SPM) Catalog 1.0, which provides positions, absolute proper motions, and photographic BV photometry for 58,880 objects at the South Galactic pole. The sky coverage of the SPM Catalog 1.0 is about 720 deg(2) in the magnitude range 5 < V < 18.5. About 55% of all catalog stars are randomly chosen, whereas the remainder contains numerous astrophysically interesting objects drawn from various lists and databases. The accuracy of positions and absolute proper motions is 40-150 mas and 3-8 mas yr-l, respectively, depending on the star's magnitude. The high-end astrometric accuracy applies to the stars brighter than V = 15. A great deal of effort was put into correcting positions and proper motions for the magnitude-dependent systematic errors. The catalog can be used for Galactic structure studies and deep CCD-frame astrometric calibration and as a database for stars, galaxies, and other objects at the south Galactic pole. The catalog is supplemented by calibrated CCD BV photometry in selected 13' x 13' areas. C1 Yale Univ, Dept Astron, New Haven, CT 06520 USA. Univ Nacl San Juan, RA-5413 San Juan, Argentina. Yale So Observ, RA-5413 San Juan, Argentina. Cerro Tololo Interamer Observ, La Serena, Chile. Beijing Normal Univ, Dept Astron, Beijing 100875, Peoples R China. Chinese Acad Sci, Shaanxi Astron Observ, Shaanxi 710600, Peoples R China. Royal Observ, Edinburgh EH9 3HJ, Midlothian, Scotland. USN, Res Lab, Washington, DC 20375 USA. RP Platais, I (reprint author), Yale Univ, Dept Astron, POB 208101, New Haven, CT 06520 USA. EM imants@astro.yale.edu RI Mendez, Rene/H-9496-2015; Mendez, Rene/J-6608-2016 NR 40 TC 66 Z9 67 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 1998 VL 116 IS 5 BP 2556 EP 2564 DI 10.1086/300620 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 134UZ UT WOS:000076763200041 ER PT J AU Mutel, RL Molnar, LA Waltman, EB Ghigo, FD AF Mutel, RL Molnar, LA Waltman, EB Ghigo, FD TI Radio emission from Algol. I. Coronal geometry and emission mechanisms determined from VLBA and Green Bank Interferometer observations SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : eclipsing; radiation mechanisms : nonthermal; radio continuum : stars; stars : coronae; stars : imaging; stars : individual (beta Aurigae) ID X-RAY-EMISSION; RS CVN BINARIES; UX-ARIETIS; HR 1099; POLARIZATION; HR-1099; QUIESCENT; SYSTEMS; FLARES; STARS AB We report dual circular polarization VLBA observations of Algol made at orbital phases 0.22-0.30 using a differential phase referencing technique. The flux density of Algol varied from 10 to 20 mJy during the observations. The radio maps show a double-lobed source separated by 1.6 mas (1.4 times the K star diameter). Although the total emission is only weakly circularly polarized, the individual lobes are strongly circularly polarized and of opposite helicity. Snapshot VLBI maps made at 3 hour intervals show Variations in the flux density of both components, but no significant motions of the centroids. We also analyze Green Bank Interferometer (GBI) synoptic observations of right- and left-circularly polarized (RCP and LCP) flux densities of Algol at 2.3 and 8.3 GHz several times a day from early 1995 to mid-1997. The resulting data set, which consists of more than 2500 observations over 2 years, is by far the most comprehensive available for any stellar system. In addition, we analyzed GBI observations of the very similar (but noneclipsing) binary system HR 1099 over the same time period in order to compare the two systems. We summarize the GBI observations using several statistical descriptions. We find no phase dependence of either the radio luminosity or circular polarization for either system. The luminosity histograms for the two systems are remarkably similar. The distribution functions are not well represented by exponentials as previously suggested, but can be represented by power laws truncated at low luminosity. The cutoff occurs at 20-30 mJy and may represent emission from a slowly varying basal level that is always detected. We confirm several previous results, including the strong dependence of spectral index on luminosity, the decrease of fractional circular polarization with luminosity, and the dependence of fractional circular polarization on orbital inclination angle. We suggest that the radio emission at 8.3 GHz is x-mode gyrosynchrotron emission from optically thin emission regions containing mildly relativistic electrons in a dipolar magnetic field. There is no evidence for highly circularly polarized coherent hares at 8.3 GHz, although it is possible that such flares occasionally occur at 2.25 GHz. The lack of orbital phase dependence in the GBI light curves, combined with the significant inclination of the VLBA structure with respect to the orbital plane, is inconsistent with previous models in which the radio lobes are located in the equatorial plane. The individual lobes seen in the VLBI maps may be associated with the polar regions, with the strong circular polarization resulting from the opposed mean magnetic field vector component along the observer's line of sight in opposite hemispheres. Astrometric results from the VLBA observations are discussed in a companion paper. C1 Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. USN, Res Lab, Washington, DC 20375 USA. Natl Radio Astron Observ, Green Bank, WV 24944 USA. RP Mutel, RL (reprint author), Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. NR 51 TC 42 Z9 42 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1998 VL 507 IS 1 BP 371 EP 383 DI 10.1086/306311 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LQ UT WOS:000077779400036 ER PT J AU Linton, MG Dahlburg, RB Fisher, GH Longcope, DW AF Linton, MG Dahlburg, RB Fisher, GH Longcope, DW TI Nonlinear evolution of kink-unstable magnetic flux tubes and solar delta-spot active regions SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; sun : activity; sun : interior; sun : magnetic fields; sunspots ID CONVECTION ZONE; EMERGING FLUX; INSTABILITY; RECONNECTION; ASYMMETRY; HELICITY; ORIGIN; FORCE AB The motivation for the work described in this paper is to understand kink-unstable magnetic flux tubes and their role in the formation of delta-spot active regions. It has been proposed that, during their rise to the photosphere, a certain fraction of convection zone flux tubes become twisted to the point where they are unstable to the current driven kink instability. These kink-unstable flux tubes then evolve toward a new kinked equilibrium as they continue to rise to the photosphere, appearing as delta-spot groups upon emergence. Because of their kinked nature, these flux tubes could be highly susceptible to flaring, explaining the very active nature of delta-spot groups. We study the kinking flux tube problem with a three-dimensional numerical model containing only the most basic features of a kink-unstable flux tube. We build on our earlier work describing the linear phase of the kink instability, and follow the evolution into the nonlinear regime: (1) We perform numerical simulations of constant-twist, kink-unstable flux tubes in an initially cylindrical equilibrium configuration in three dimensions, in a high-beta pressure-confined environment. We consider many different initial configurations, including the Gold-Hoyle flux tube. (2) These numerical calculations confirm the growth-rate predictions of our earlier work, when viscous dissipation is included. They also confirm our velocity profile predictions. (3) The flux tubes evolve toward new helically symmetric equilibrium configurations. (4) The timescale for saturation to the kinked equilibrium configuration is tau(sat) similar to 10/omega(0), where omega(0) is the linear growth rate calculated as in the earlier paper. (5) The cylindrically symmetric part of the kinked equilibrium is well described by the m = 0 Chandrasekhar-Kendall functions (i.e., the Lundquist field). The m = I helically symmetric part, however, is not well described by the m = 1 Chandrasekhar-Kendall functions. (6) The equilibrium kink amplitudes are not large, at less than one-third of the tube radius. (7) The peak kinetic energy of the instability can be predicted from the initial excess perpendicular magnetic energy. (8) The amplitudes of the kinked tubes are large enough to give a delta-spot region tilt angle of up to 30 degrees away from that of an unkinked tube. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. RP Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RI Fisher, George/G-1380-2015 OI Fisher, George/0000-0002-6912-5704 NR 43 TC 48 Z9 48 U1 0 U2 0 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 NOV 1 PY 1998 VL 507 IS 1 BP 404 EP 416 DI 10.1086/306299 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LQ UT WOS:000077779400040 ER PT J AU Warren, HP Mariska, JT Wilhelm, K AF Warren, HP Mariska, JT Wilhelm, K TI High-resolution observations of the solar hydrogen Lyman lines in the quiet sun with the sumer instrument on SOHO SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE line, profiles; sun, chromosphere; sun, UV radiation ID TRANSITION REGION; RADIOMETRIC CALIBRATION; ENERGY-BALANCE; O-VI; ALPHA; SPECTROMETER; TELESCOPE; SPECTRA; MODELS; WAVELENGTHS AB We present high-resolution observations of the higher H Lyman series lines taken with the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) experiment flown on the Solar and Heliospheric Observatory (SOHO) spacecraft. We have used systematic observations extending from disk center to the solar limb to compute average profiles for representative solar features of the quiet Sun, limb-brightening curves, and full-disk, quiet-Sun profiles for Ly beta through Ly lambda(11) and the Lyman continuum. The effects of radiative transfer are apparent in all of the line profiles we studied. The average quiet-Sun profiles for Ly beta through Ly epsilon are self-reversed, and the remaining lines are flat-topped The characteristics of the line profiles vary markedly with intensity. We observe strong enhancements in the red wings of network profiles, while the faint cell-center profiles are nearly symmetric. We also find that the intensities of the H Lyman lines increase at the limb, although the limb brightening is weak compared to optically thin transition region emission lines and largely obscured by the intensity variations observed in the quiet Sun. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. RP Warren, HP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 58, Cambridge, MA 02138 USA. EM hpw@dogwood.nrl.navy.mil NR 39 TC 67 Z9 68 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD NOV PY 1998 VL 119 IS 1 BP 105 EP 120 DI 10.1086/313151 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 139TU UT WOS:000077046400007 ER PT J AU Christen, BR Moore, JL AF Christen, BR Moore, JL TI A descriptive analysis of "not aeronautically adaptable" dispositions in the US Navy SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID RIGHT STUFF; PERSONALITY AB Background: All aviation personnel in the U.S. Navy are evaluated for aeronautical adaptability (AA) in both initial and periodic examinations and for daily aeromedical disposition. By definition, all aviation personnel with a diagnosed personality disorder or those with maladaptive personality traits that have had a documented effect on safety of flight, crew coordination, or mission completion, are determined to be Not Aeronautically Adapted (NAA). Methods: NAA dispositions were examined for demographic data, basis for disposition, and frequency of personality features. Results: NAA dispositions were made on the basis of personality disorders and maladaptive personality traits in 29% and 35% of the cases, respectively. The officer and enlisted NAA dispositions were distinctly different in terms of frequency of personality features. Obsessive-compulsive features were present in 58% of officer and 10% of enlisted NAA dispositions. Dependent and avoidant features were present in excess in comparison to psychologically healthy aviators, suggesting the incompatibility of these features with aviation. C1 Naval Operat Med Inst, Pensacola, FL 32508 USA. RP Christen, BR (reprint author), Naval Operat Med Inst, Code 032R,220 Hovey Rd,Naval Air Stn, Pensacola, FL 32508 USA. NR 20 TC 4 Z9 4 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 NOV PY 1998 VL 69 IS 11 BP 1071 EP 1075 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 133PA UT WOS:000076693900008 PM 9819164 ER PT J AU Selz, KA Mandell, AJ Shlesinger, MF AF Selz, KA Mandell, AJ Shlesinger, MF TI Hydrophobic free energy eigenfunctions of pore, channel, and transporter proteins contain beta-burst patterns SO BIOPHYSICAL JOURNAL LA English DT Article ID SHAKER POTASSIUM CHANNELS; GLOBULAR-PROTEINS; MEMBRANE-PROTEINS; 3-DIMENSIONAL STRUCTURE; TRANSMEMBRANE DOMAIN; MOLECULAR-CLONING; ESCHERICHIA-COLI; SODIUM-CHANNEL; SEQUENCES; PREDICTION AB Hydropathy plots are often used in place of missing physical data to model transmembrane proteins that are difficult to crystallize. The sequential maxima of their graphs approximate the number and locations of transmembrane segments, but potentially useful additional information about sequential hydrophobic variation is lost in this smoothing procedure. To explore a broader range of hydrophobic variations without loss of the transmembrane segment-relevant sequential maxima, we utilize a sequence of linear decompositions and transformations of the n-length hydrophobic free energy sequences, H(i, i = 1...n), of proteins. Constructions of hydrophobic free energy eigenfunctions, psi(1), from M-lagged, M x M autocovariance matrices, C(M), were followed by their all-poles, maximum entropy power spectral, S(omega)(psi(1)), and Mexican Hat wavelet, W (a, b)(psi(1)), transformations. These procedures yielded graphs indicative of inverse frequencies, omega(-1), and sequence locations of hydrophobic modes suggestive of secondary and supersecondary protein structures. The graphs of these computations discriminated between Greek Key, Jelly Role, and Up and Down categories of antiparallel p-barrel proteins. With these methods, examples of porins, connexins, hexose transporters, nuclear membrane proteins, and potassium but not sodium channels appear to belong to the Up and Down antiparallel beta-barrel variety. C1 Cielo Inst, Asheville, NC 28804 USA. Emory Univ, Sch Med, Dept Psychiat & Behav Sci, Atlanta, GA 30322 USA. Florida Atlantic Univ, Dept Math Sci, Boca Raton, FL 33431 USA. Off Naval Res, Div Phys Sci, Arlington, VA 22217 USA. RP Selz, KA (reprint author), Cielo Inst, 486 Sunset Dr, Asheville, NC 28804 USA. EM cieloinst@aol.com FU NIMH NIH HHS [R43 MH58026-01] NR 72 TC 15 Z9 15 U1 0 U2 0 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD NOV PY 1998 VL 75 IS 5 BP 2332 EP 2342 PG 11 WC Biophysics SC Biophysics GA 132PF UT WOS:000076638200023 PM 9788928 ER PT J AU Xu, ZS Lemieux, RP Natansohn, A Rochon, P Shashidhar, R AF Xu, ZS Lemieux, RP Natansohn, A Rochon, P Shashidhar, R TI Azobenzene-assisted alignment of ferroelectric liquid crystals in the chiral smectic C phase with an alternating current field SO CHEMISTRY OF MATERIALS LA English DT Article AB An unexpected observation of aligning ferroelectric liquid crystals (FLCs) is described. FLCs containing azobenzene, or doped with small amounts of azobenzene compounds, can be relatively rapidly aligned in the SmC* phase with an ac field. C1 Queens Univ, Dept Chem, Kingston, ON K7L 3N6, Canada. Royal Mil Coll Canada, Dept Phys, Kingston, ON K7K 5L0, Canada. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Natansohn, A (reprint author), Queens Univ, Dept Chem, Kingston, ON K7L 3N6, Canada. NR 13 TC 7 Z9 7 U1 1 U2 4 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 NOV PY 1998 VL 10 IS 11 BP 3269 EP + DI 10.1021/cm980336w PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 141EG UT WOS:000077129200005 ER PT J AU Prasad, K Yetter, RA Smooke, MD AF Prasad, K Yetter, RA Smooke, MD TI No eigenvalue method for computing the burning rates of HMX propellants SO COMBUSTION AND FLAME LA English DT Article ID KINETICS; PHASE AB A mathematical model for a three-tiered system consisting of solid, liquid, and gas is derived for studying the combustion of HMX participants. The resulting nonlinear two-point boundary value problem is solved bu Newton's method with adaptive gridding techniques. In this study the burning rate is computed as an eigenvalue, which removes the uncertainty associated with employing evaporation and condensation rate laws in its evaluation, Results are presented for laser-assisted and self-deflagration of HMX monopropellants and are compared with experimental results. The burning rates are computed over a wide range of ambient pressures and compare well with experimental results from 1 to 90 atmospheres. The burning rate is found to be proportional to the pressure raised to the 0.82 power, Sensitivity of the burning rate to initial propellant temperature is calculated and found to be extremely low, in agreement with past theoretical predictions and experimental data, Results for laser-assisted combustion show a distinct primary and secondary flame separated by a dark zone, the length of which is dependent upon the incident laser flux intensity. (C) 1998 by The Combustion Institute. C1 USN, Res Lab, Washington, DC 20375 USA. Princeton Univ, Princeton, NJ 08544 USA. Yale Univ, New Haven, CT 06520 USA. RP Prasad, K (reprint author), USN, Res Lab, Code 6410, Washington, DC 20375 USA. NR 24 TC 31 Z9 33 U1 0 U2 3 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 NOV PY 1998 VL 115 IS 3 BP 406 EP 416 DI 10.1016/S0010-2180(98)00009-1 PG 11 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA ZW416 UT WOS:000074408800011 ER PT J AU Abraham, FF Broughton, JQ Bernstein, N Kaxiras, E AF Abraham, FF Broughton, JQ Bernstein, N Kaxiras, E TI Spanning the length scales in dynamic simulation SO COMPUTERS IN PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS; INSTABILITY DYNAMICS; COMPUTER-SIMULATION; FRACTURE; SILICON; DEFECTS C1 IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. Harvard Univ, Dept Phys, Cambridge, MA 02138 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP Abraham, FF (reprint author), IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. EM farid@almaden.ibm.com NR 17 TC 213 Z9 216 U1 1 U2 20 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0894-1866 J9 COMPUT PHYS JI Comput. Phys. PD NOV-DEC PY 1998 VL 12 IS 6 BP 538 EP 546 DI 10.1063/1.168756 PG 9 WC Computer Science, Interdisciplinary Applications; Physics, Multidisciplinary; Physics, Mathematical SC Computer Science; Physics GA 149NP UT WOS:000077611900013 ER PT J AU Valle-Levinson, A Miller, JL Wheless, GH AF Valle-Levinson, A Miller, JL Wheless, GH TI Enhanced stratification in the lower Chesapeake Bay following northeasterly winds SO CONTINENTAL SHELF RESEARCH LA English DT Article ID SEA-LEVEL; CURRENTS; ESTUARY; OCEAN; CIRCULATION; SHALLOW AB Density data from a lower Chesapeake Bay transect obtained after two northeasterly wind events were used to describe the effects of these events on the density field in the lower estuary. The first northeaster occurred in early August 1995 and the second northeaster was related to the passage of hurricane Felix off the lower bay in mid-August 1995. The latter northeaster prolonged a period of persistent winds from the N and NE that began in early August and caused storm surges of similar magnitude to the former northeaster. The salinity fields observed after the early August event suggested encroachment of coastal waters into the lower bay as reflected by high salinities throughout the transect. Two days after weakening of the winds related to Felix, the density distribution across the lower bay showed strongly stratified conditions. This behavior suggested that the inflow of coastal water into the lower bay and the wind mixing related to Felix combined to produce a vertically uniform density gradient perpendicular to the bay entrance that relaxed after the winds weakened. This weakening of the winds coincided with neap tidal currents, which were not energetic enough to maintain vertical homogeneity and must have allowed the self-adjustment of the density gradient and the seaward advection of relatively buoyant waters near the surface. These mechanisms were illustrated with simplified numerical experiments. The findings of this study are used to propose the hypothesis that, in general, enhanced stratification and flushing in the lower bay will ensue the relaxation of a northeasterly wind event, provided that this relaxation coincides with a weak friction regime, i.e., neap tides. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Old Dominion Univ, Ctr Coastal Phys Oceanog, Norfolk, VA 23529 USA. USN, Res Lab, Stennis Space Ctr, MS 39524 USA. RP Valle-Levinson, A (reprint author), Old Dominion Univ, Ctr Coastal Phys Oceanog, Norfolk, VA 23529 USA. NR 22 TC 6 Z9 6 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD NOV PY 1998 VL 18 IS 13 BP 1631 EP 1647 DI 10.1016/S0278-4343(98)00067-3 PG 17 WC Oceanography SC Oceanography GA 147HE UT WOS:000077482600006 ER PT J AU McCafferty, E AF McCafferty, E TI Effect of electrolyte volume on the acid dissolution of aluminum alloy 7075 SO CORROSION LA English DT Article DE acid dissolution; Al 7075; aluminum; electrolyte; hydrochloric acid; molarity; volume effects ID CHLORIDE SOLUTIONS; KINETICS; IRON AB Dissolution of aluminum alloy 7075 (UNS A97075) was studied using weight-loss measurements in a series of hydrochloric acid (HCl) solutions varying in concentration from 0.5 M to 2 M. The open-circuit reaction was observed to be first order in the hydrogen ion. In acid solutions having a fixed supply of hydrogen ions, corrosion of Al 7075 was arrested by depletion of that available supply. For a given initial acid molarity (M) and a given initial surface area, the total amount of corrosion (weight loss [G]) is given by G = 0.0101 VM where V is the volume of solution. For a given set of conditions (initial acid concentration, initial surface area, and volume of solution), the time for cessation of the corrosion reaction as calculated from first-order reaction kinetics was in agreement with experimentally determined values. Two corrosion systems were discussed as possible applications involving cessation of a corrosion, reaction in acid environments caused by depletion of the hydrogen ion supply. C1 USN, Res Lab, Washington, DC 20375 USA. RP McCafferty, E (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 14 TC 5 Z9 5 U1 0 U2 1 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 USA SN 0010-9312 J9 CORROSION JI Corrosion PD NOV PY 1998 VL 54 IS 11 BP 862 EP 868 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 136GK UT WOS:000076850300002 ER PT J AU Munter, DW AF Munter, DW TI The difficult diagnosis - Preface SO EMERGENCY MEDICINE CLINICS OF NORTH AMERICA LA English DT Editorial Material C1 Natl Naval Med Ctr, Dept Emergency Med, Portsmouth, VA 23320 USA. RP Munter, DW (reprint author), Natl Naval Med Ctr, Dept Emergency Med, Portsmouth, VA 23320 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0733-8627 J9 EMERG MED CLIN N AM JI Emerg. Med. Clin. N. Am. PD NOV PY 1998 VL 16 IS 4 BP XI EP XII DI 10.1016/S0733-8627(05)70027-4 PG 2 WC Emergency Medicine SC Emergency Medicine GA 147LQ UT WOS:000077569800001 ER PT J AU Burgher, SW AF Burgher, SW TI Acute scrotal pain SO EMERGENCY MEDICINE CLINICS OF NORTH AMERICA LA English DT Article ID COLOR DOPPLER SONOGRAPHY; TESTICULAR TORSION; SPERMATIC CORD; AORTIC-ANEURYSM; CONSERVATIVE MANAGEMENT; ACUTE EPIDIDYMITIS; MUMPS ORCHITIS; CHILDREN; DIAGNOSIS; TESTIS AB The diagnosis of acute scrotal pain can be difficult. The most common causes include torsion of a testicular appendage, epididymitis, and testicular torsion, which account for 85% to 90% of all cases. These entities may be clinically indistinguishable because characteristic symptoms and signs for each overlap, whereas pathognomonic features are uncommon. Diagnostic accuracy without delay is required to avoid the loss of testicular function in testicular torsion cases and to avoid unnecessary surgery in other cases. A thorough understanding of the key clinical features of each entity, coupled with an understanding of the appropriate use of perfusion imaging studies, will equip the emergency physician with the tools to accomplish this task. C1 Natl Naval Med Ctr, Dept Emergency Med, Portsmouth, VA 23708 USA. RP Burgher, SW (reprint author), Natl Naval Med Ctr, Dept Emergency Med, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 99 TC 18 Z9 20 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0733-8627 J9 EMERG MED CLIN N AM JI Emerg. Med. Clin. N. Am. PD NOV PY 1998 VL 16 IS 4 BP 781 EP + DI 10.1016/S0733-8627(05)70033-X PG 30 WC Emergency Medicine SC Emergency Medicine GA 147LQ UT WOS:000077569800007 PM 9889740 ER PT J AU Zackowski, SW AF Zackowski, SW TI Chronic recurrent abdominal pain SO EMERGENCY MEDICINE CLINICS OF NORTH AMERICA LA English DT Article ID FAMILIAL MEDITERRANEAN FEVER; FUNCTIONAL DYSPEPSIA; PORPHYRIA; CISAPRIDE; SYMPTOMS; AMYLOIDOSIS; PROGNOSIS; MIGRAINE; DISEASE; ATTACKS AB Chronic recurrent abdominal pain remains a common medical and surgical problem, frequently dismissed as functional. Instead, these patients should be approached systematically, based on the pattern of recurrent abdominal pain. It is vital to seek out the potential cause of this type of chronic pain because specific and often curative treatment is available. C1 Natl Naval Med Ctr, Dept Emergency Med, Portsmouth, VA USA. RP Zackowski, SW (reprint author), 614 Piping Rock Dr, Chesapeake, VA 23322 USA. EM szackowski@nol.com NR 58 TC 4 Z9 4 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0733-8627 J9 EMERG MED CLIN N AM JI Emerg. Med. Clin. N. Am. PD NOV PY 1998 VL 16 IS 4 BP 877 EP + DI 10.1016/S0733-8627(05)70037-7 PG 19 WC Emergency Medicine SC Emergency Medicine GA 147LQ UT WOS:000077569800011 PM 9889744 ER PT J AU Knoke, JD Gray, GC Garland, FC AF Knoke, JD Gray, GC Garland, FC TI Testicular cancer and Persian Gulf War service SO EPIDEMIOLOGY LA English DT Article DE Persian Gulf War; testicular cancer; hospitalization; selection effect; military medicine; cohort studies ID TESTIS AB We studied whether regular, active-duty servicemen deployed to the Persian Gulf War were at increased risk of testicular cancer compared with nondeployed Gulf War-era servicemen from August 1991 through March 31, 1996, using a Cox proportional hazards model for survival analysis with covariates. Race was an important predictor of hospitalization for testicular cancer [rate ratio (RR) = 0.19; 95% confidence interval (CI) = 0.12-0.29 for blacks, and RR = 0.59; 95% CI = 0.39-0.91 for Hispanics, other, and unknown (combined), relative to whites]. Age effects were modest (RR = 1.19; 95% CI = 0.91-1.56 for those of ages 22-25 years, and RR = 1.24; 95% CI = 0.96-1.59 for those of ages 26-31 years, compared with those of ages 17-21 years). Risk also varied with occupation (RR = 1.56; 95% CI = 1.23-2.00 for those in electronic equipment repair; RR = 1.26; 95% CI = 1.01-1.58 for those in electrical/mechanical repair; and RR = 1.42; 95% CI 0.93-2.17 for those in construction-related trades, compared with those in other occupations). Deployment status was not important (RR = 1.05; 95% CI = 0.86-1.29 for the deployed compared with the nondeployed). There was an increase in testicular cancer in the deployed group in the immediate postwar period that was consistent with a previous report of a standardized RR of 2.12; 95% CI = 1.11-4.02 (compared with the nondeployed group) in the last 5 months of 1991, but by 4 years after the end of deployment, the cumulative risks for the two groups were not different. An additional analysis suggested that the immediate postwar increase in the deployed was likely due to regression to the mean after a healthy serviceman selection effect for deployment and the deferment of care during deployment. C1 USN, Hlth Res Ctr, Dept Hlth Sci & Epidemiol, Div Emerging Illness, San Diego, CA 92186 USA. RP Knoke, JD (reprint author), USN, Hlth Res Ctr, Dept Hlth Sci & Epidemiol, Div Emerging Illness, POB 85122, San Diego, CA 92186 USA. NR 17 TC 27 Z9 28 U1 1 U2 6 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 1044-3983 J9 EPIDEMIOLOGY JI Epidemiology PD NOV PY 1998 VL 9 IS 6 BP 648 EP 653 DI 10.1097/00001648-199811000-00015 PG 6 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 130BR UT WOS:000076499800015 PM 9799176 ER PT J AU Swezey, RW Owens, JM Bergondy, ML Salas, E AF Swezey, RW Owens, JM Bergondy, ML Salas, E TI Task and training requirements analysis methodology (TTRAM): an analytic methodology for identifying potential training uses of simulator networks in teamwork-intensive task environments SO ERGONOMICS LA English DT Article DE simulator networking; team training; training analysis ID MILITARY AB A methodology designed to identify potential application areas for use of networked simulations is presented. The technique, known as task and training requirements analysis methodology (TTRAM), has been independently applied to the analysis of numerous US military aircraft simulator networking requirements, and appears to effectively discriminate tasks that are prone to skill decay, that are critical to mission success, that require high levels of internal and external teamwork, and that require additional training support. C1 InterSci Amer Inc, Leesburg, VA 22075 USA. USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. RP Swezey, RW (reprint author), InterSci Amer Inc, 312 E Market St,Suite G, Leesburg, VA 22075 USA. NR 29 TC 6 Z9 6 U1 1 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0014-0139 J9 ERGONOMICS JI Ergonomics PD NOV PY 1998 VL 41 IS 11 BP 1678 EP 1697 DI 10.1080/001401398186135 PG 20 WC Engineering, Industrial; Ergonomics; Psychology, Applied; Psychology SC Engineering; Psychology GA 136DH UT WOS:000076842900009 PM 9819581 ER PT J AU Kellogg, JC Bodner, SE Obenschain, SP Sethian, JD AF Kellogg, JC Bodner, SE Obenschain, SP Sethian, JD TI Prospects for inertial fusion energy with a KrF laser SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 13th Topical Meeting on the Technology of Fusion Energy CY JUN 07-11, 1998 CL NASHVILLE, TENNESSEE SP Amer Nucl Soc ID INDUCED SPATIAL INCOHERENCE; ILLUMINATION AB Previous reactor studies indicate that a practical laser fusion power plant will require target gains of about 100. This level of energy gain appears possible with direct-drive targets now being designed and optimized at the Naval Research Laboratory (NRL). With direct-drive, the light is absorbed directly on the pellet shell, thereby maximizing the coupling efficiency. The current status of NRL's high gain target designs will be presented. To obtain sufficiently high target gains for a fusion reactor, NRL has had to take advantage of three optimizations. First, the laser beam illumination on the pellet has to be extremely uniform. High-mode beam nonuniformities in the range of 0.2% rms are required, along with low-mode nonuniformities of about 1%. The equivalent nonuniformity levels have already been achieved, in planar geometry, with NRL's KrF laser. Second, the rocket efficiency has to be maximized by depositing the laser energy deeply into the pellet. KrF, with 1/4 micron wavelength light, deposits at a high plasma density. Third, the target gain is optimized by "zooming" the laser beam inward during the implosion, thereby matching the laser spot size to the decreasing pellet diameter. This optical zooming is easily implemented on KrF lasers. Although the laser-target physics leads us to KrF, there are several engineering challenges in developing a laser of this type with sufficient energy, rep-rate, reliability, and economy for a practical reactor. Some of these challenges are the lifetime of the emitter and pressure foil in the electron-beam pumped amplifiers, the ability to clear the laser gas between pulses without sacrificing beam quality, and the overall efficiency of the system. Technologies and techniques which might meet these challenges have been partially developed elsewhere, but they are not necessarily in a parameter range appropriate for laser fusion, and they have yet to be integrated into a single system. We have a conceptual design for a 400-Joule, 5-Hz KrF laser which would serve as a test bed for these technologies. There are also engineering challenges in the design of a target chamber for a laser fusion reactor, including the protection of the first wall from the transient x-ray flux, and the final grazing incidence metal mirror which will be in direct line of sight of high energy neutrons from the burning pellet. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Kellogg, JC (reprint author), USN, Res Lab, Div Plasma Phys, Code 6730, Washington, DC 20375 USA. NR 20 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD NOV PY 1998 VL 34 IS 3 BP 319 EP 325 PN 2 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 145RE UT WOS:000077384500007 ER PT J AU Helmer, O AF Helmer, O TI Some gaps in futures research SO FUTURES LA English DT Article AB Three gaps in the present futures research methodology are presented as a challenge to workers in the field. In the author's opinion, the elimination of these deficiencies would quite markedly enhance the applicability of futures research to long-range planning. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ So Calif, Los Angeles, CA 90089 USA. USN, Postgrad Sch, Monterey, CA USA. RP Helmer, O (reprint author), 26180 Valley View, Carmel, CA 93923 USA. NR 7 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 0016-3287 J9 FUTURES JI Futures PD NOV PY 1998 VL 30 IS 9 BP 941 EP 943 PG 3 WC Economics; Planning & Development SC Business & Economics; Public Administration GA 139YD UT WOS:000077058100008 ER PT J AU Rosenblum, L Burdea, G Tachi, S AF Rosenblum, L Burdea, G Tachi, S TI VR reborn SO IEEE COMPUTER GRAPHICS AND APPLICATIONS LA English DT Editorial Material C1 USN, Adv Informat Technol Branch, Div Informat Technol, Res Lab, Washington, DC 20375 USA. Rutgers State Univ, Human Machine Interface Lab, Piscataway, NJ 08855 USA. Univ Tokyo, Dept Math Engn & Informat Phys, Tokyo, Japan. RP Rosenblum, L (reprint author), USN, Adv Informat Technol Branch, Div Informat Technol, Res Lab, Code 5580, Washington, DC 20375 USA. NR 1 TC 1 Z9 1 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 0272-1716 J9 IEEE COMPUT GRAPH JI IEEE Comput. Graph. Appl. PD NOV-DEC PY 1998 VL 18 IS 6 BP 21 EP 23 DI 10.1109/MCG.1998.734975 PG 3 WC Computer Science, Software Engineering SC Computer Science GA 132WC UT WOS:000076652800005 ER PT J AU Schaafsma, DT Shaw, LB Cole, B Sanghera, JS Aggarwal, ID AF Schaafsma, DT Shaw, LB Cole, B Sanghera, JS Aggarwal, ID TI Modeling of Dy3+-doped GeAsSe glass 1.3-mu m optical fiber amplifiers SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE communication system performance; infrared spectroscopy; optical fiber amplifiers; optical fiber communication; optical fiber materials; optical materials/devices ID MU-M AB We present a model for optical amplification at 1.3 mu m using Dy3+ in fibers made from a low phonon energy glass, based on GeAsSe, This model uses in-band pumping at 1.28 mu m, takes into account the spectral distribution of amplified spontaneous emission, and allows for bottlenecking of excited ions into the intermediate states in Dy as well as the excited state absorption (ESA) from those levels. Using data obtained from spectroscopic measurements and Judd-Ofelt calculations, our model shows that very high gain (>30 dB) is possible in short lengths (40-100 cm) of fiber. Given the very high quantum efficiency of the radiative transition in this glass, we show that bottlenecking and ESA should not have a significant impact on device performance. We also predict that devices made from this fiber should have a very high tolerance to the passive loss of the fiber. C1 USN, Res Lab, Washington, DC 20375 USA. RP Schaafsma, DT (reprint author), USN, Res Lab, Code 5606, Washington, DC 20375 USA. NR 12 TC 16 Z9 17 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD NOV PY 1998 VL 10 IS 11 BP 1548 EP 1550 DI 10.1109/68.726745 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 129TY UT WOS:000076480200008 ER PT J AU Todd, MD Johnson, GA Althouse, BA Vohra, ST AF Todd, MD Johnson, GA Althouse, BA Vohra, ST TI Flexural beam-based fiber Bragg grating accelerometers SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE accelerometers; Bragg gratings; design methodology; optical sensors AB A flexural beam is utilized as the primary transduction mechanism for demonstrating a series of fiber Bragg grating (FBG) accelerometers. The fully packaged FBG accelerometers reported in this work have many desirable features including good acceleration sensitivity (212.5 mu epsilon/g), high resonant frequencies (on the order of 1 kHz), very low cross-axis sensitivity (< 1% of the primary axial responsivity), and low noise (similar to 1 mg/root Hz near 1 Hz). Arrays of such devices can be utilized in a variety of applications, including structural monitoring. Closed-form analytical formulas describing the resonant frequency and responsivity of the FBG accelerometer are provided which may be utilized to tailor the sensor performance to specific applications. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. URF Inc, Greenbelt, MD 20770 USA. RP Todd, MD (reprint author), USN, Res Lab, Div Opt Sci, Code 5670, Washington, DC 20375 USA. NR 7 TC 95 Z9 119 U1 1 U2 14 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD NOV PY 1998 VL 10 IS 11 BP 1605 EP 1607 DI 10.1109/68.726764 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 129TY UT WOS:000076480200027 ER PT J AU Kang, JU Frankel, MY Esman, RD AF Kang, JU Frankel, MY Esman, RD TI Highly parallel pulsed optoelectronic analog-digital converter SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE analog-digital conversion; optical data processing; wavelength-division multiplexing AB We characterize the performance of a highly parallel pulsed optoelectronic analog to digital converter. The system is based on a time-domain to wavelength-domain mapping, such that an input analog signal is parallelized using a wavelength-division-demultiplexed scheme. Each parallel wavelength channel is then digitized using conventional, slow electronic analog-digital converters. We use narrow-band signals up to 18 GHz and histogram testing to characterize the system. From the measurements, we deduce the effective number of bits of the system to be similar to 6 and similar to 5 bits for 4 and 36 giga-samples-per-second (GSPS) sampling rates, respectively. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kang, JU (reprint author), USN, Res Lab, Code 5672, Washington, DC 20375 USA. RI Kang, Jin/A-3228-2010 NR 6 TC 19 Z9 19 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD NOV PY 1998 VL 10 IS 11 BP 1626 EP 1628 DI 10.1109/68.726771 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 129TY UT WOS:000076480200034 ER PT J AU Schneidewind, NF AF Schneidewind, NF TI Professional organizations should define standards SO IEEE SOFTWARE LA English DT Editorial Material C1 USN, Postgrad Sch, Software Metr Res Ctr, Washington, DC 20350 USA. RP Schneidewind, NF (reprint author), USN, Postgrad Sch, Software Metr Res Ctr, Washington, DC 20350 USA. 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 0740-7459 J9 IEEE SOFTWARE JI IEEE Softw. PD NOV-DEC PY 1998 VL 15 IS 6 BP 96 EP 98 DI 10.1109/MS.1998.730856 PG 3 WC Computer Science, Software Engineering SC Computer Science GA 138HY UT WOS:000076967500025 ER PT J AU Kiriakidis, K AF Kiriakidis, K TI Fuzzy model-based control of complex plants SO IEEE TRANSACTIONS ON FUZZY SYSTEMS LA English DT Article DE fuzzy models; observers; robustness; state-space methods; uncertainty ID UNCERTAIN NONLINEAR-SYSTEMS; ROBUST STABILIZATION; STABILITY ANALYSIS; DESIGN; IDENTIFICATION; ISSUES AB In the field of fuzzy modeling, the Takagi-Sugeno fuzzy model has been used to approximate accurately the dynamics of complex plants. This paper addresses two control design problems associated with state-space realizations of such fuzzy models. First, we treat the stability robustness of fuzzy model-based controllers against modeling uncertainty. Second, we develop observer-based control schemes and further investigate the behavior of estimated-state feedback. In both cases, we provide sufficient conditions that guarantee stability of the closed loop. The results are demonstrated on the fuzzy model of a gas furnace process. C1 USN Acad, Dept Weap & Syst Engn, Annapolis, MD 21402 USA. RP Kiriakidis, K (reprint author), USN Acad, Dept Weap & Syst Engn, Annapolis, MD 21402 USA. NR 28 TC 77 Z9 81 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1063-6706 J9 IEEE T FUZZY SYST JI IEEE Trans. Fuzzy Syst. PD NOV PY 1998 VL 6 IS 4 BP 517 EP 529 DI 10.1109/91.728444 PG 13 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 137KT UT WOS:000076914500007 ER PT J AU Moskowitz, IS Greenwald, SJ Kang, MH AF Moskowitz, IS Greenwald, SJ Kang, MH TI An analysis of the timed Z-channel SO IEEE TRANSACTIONS ON INFORMATION THEORY LA English DT Letter DE channel capacity; computer network; computer security; covert channel; CPU scheduling; timing channel; Z-channel ID CAPACITY AB Golomb analyzed the 2 channel, a memoryless channel with two input symbols and two output symbols, where one of the input symbols is transmitted with noise while the other is transmitted without noise, and the output symbol transmission times are equal. We generalize to the timed 2-channel, where the output symbol transmission times are not equal. The timed Z-channel appears as the basis for a large class of covert (communication) channels appearing in multilevel secure computer systems. we give a detailed mathematical analysis of the timed Z-channel and report a result expressing the capacity of the timed Z-channel as the log of the root of a characteristic equation. This generalizes Shannon's work on noiseless channels for this special case. We also report a new result bounding the timed Z-channel's capacity from below. We show how an interesting observation that Golomb reported for the Z-channel also holds for the timed Z-channel. C1 USN, Res Lab, Div Informat Technol, Ctr High Assurance Comp Syst, Washington, DC 20375 USA. RP Moskowitz, IS (reprint author), USN, Res Lab, Div Informat Technol, Ctr High Assurance Comp Syst, Mail Code 5540, Washington, DC 20375 USA. NR 29 TC 7 Z9 8 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9448 J9 IEEE T INFORM THEORY JI IEEE Trans. Inf. Theory PD NOV PY 1998 VL 44 IS 7 BP 3162 EP 3168 DI 10.1109/18.737549 PG 7 WC Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 166UE UT WOS:000078594900037 ER PT J AU Biernacki, PD Nichols, LT Enders, DG Williams, KJ Esman, RD AF Biernacki, PD Nichols, LT Enders, DG Williams, KJ Esman, RD TI A two-channel optical downconverter for phase detection SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE downconversion; fiber-optic link; microwave phase detection; photonics; remoting ID LINK AB Experimental results for a two-channel optical downconverter link operating from 2 to 18 GHz are presented. Using low-noise preamplifiers results in a noise figure (NF) of 8.5-14 dB over the frequency range of 2 18 GHz. For the first time, relative phase measurements between optically downconverted signals have been performed. An in-phase/quadrature phase-measurement technique indicates a phase precision of +/-2 degrees with as little as -60 dBm radio frequency (RF) received power. Comparing the optical microwave downconverter to an electrical microwave downconverter in terms of phase detection reveals similar performance between the two systems. C1 USN, Res Lab, Washington, DC 20375 USA. RP Biernacki, PD (reprint author), USN, Res Lab, Code 5672, Washington, DC 20375 USA. NR 7 TC 5 Z9 5 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD NOV PY 1998 VL 46 IS 11 BP 1784 EP 1787 DI 10.1109/22.734580 PN 1 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA 140DP UT WOS:000077071800025 ER PT J AU Heitmeyer, C Kirby, J Labaw, B Archer, M Bharadwaj, R AF Heitmeyer, C Kirby, J Labaw, B Archer, M Bharadwaj, R TI Using abstraction and model checking to detect safety violations in requirements specifications SO IEEE TRANSACTIONS ON SOFTWARE ENGINEERING LA English DT Article DE requirements; specification; abstraction; model checking; formal methods; verification; safety analysis; simulation; consistency checking; SCR ID SYSTEMS; SOFTWARE; DESIGN AB Exposing inconsistencies can uncover many defects in software specifications. One approach to exposing inconsistencies analyzes two redundant specifications, one operational and the other property-based, and reports discrepancies. This paper describes a "practical" formal method, based on this approach and the SCR (Software Cost Reduction) tabular notation, that can expose inconsistencies in software requirements specifications. Because users of the method do not need advanced mathematical training or theorem proving skills, most software developers should be able to apply the method without extraordinary effort. This paper also describes an application of the method which exposed a safety violation in the contractor-produced software requirements specification of a sizable, safety-critical control system. Because the enormous state space of specifications of practical software usually renders direct analysis impractical, a common approach is to apply abstraction to the specification. To reduce the state space of the control system specification, two "pushbutton" abstraction methods were applied, one which automatically removes irrelevant variables and a second which replaces the large, possibly infinite, type sets of certain variables with smaller type sets. Analyzing the reduced specification with the model checker Spin uncovered a possible safety violation. Simulation demonstrated that the safety violation was not spurious but an actual defect in the original specification. C1 USN, Res Lab, Ctr High Assurance Comp Syst, Washington, DC 20375 USA. RP USN, Res Lab, Ctr High Assurance Comp Syst, Code 5546,4555 Overlook Ave SW, Washington, DC 20375 USA. EM heitmeyer@itd.nrl.navy.mil; kirby@itd.nrl.navy.mil; labaw@itd.nrl.navy.mil; archer@itd.nrl.navy.mil; ramesh@itd.nrl.navy.mil RI Heitmeyer, Constance/F-6500-2011; OI Heitmeyer, Constance/0000-0001-7942-9309 NR 66 TC 81 Z9 83 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 NOV PY 1998 VL 24 IS 11 BP 927 EP 948 DI 10.1109/32.730543 PG 22 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 139CL UT WOS:000077010000004 ER PT J AU Dell, RF AF Dell, RF TI Optimizing army base realignment and closure SO INTERFACES LA English DT Article DE military; cost-effectiveness; programming; integer AB In April 1997, the United States Army announced that savings had finally overtaken costs in closing or realigning 803 of its installations worldwide. This milestone occurred in the ninth year of a 13-year program approved by Congress and Presidents Reagan, Bush, and Clinton. The cost of this program is $5.3 billion, and when complete, the army expects annual savings of $996 million in perpetuity. A mixed-integer linear program, BRACAS (base realignment and closure action scheduler), helped the army budget for the 29 closures and 11 realignments approved by Congress and President Clinton in 1995. The army used BRACAS to schedule optimally the $2 billion in BRAG costs for these 40 installations over the six-year period mandated by Congress; associated annual savings will be $360 million. C1 USN, Postgrad Sch, Dept Operat Res, Monterey, CA 93943 USA. RP Dell, RF (reprint author), USN, Postgrad Sch, Dept Operat Res, Monterey, CA 93943 USA. NR 25 TC 8 Z9 8 U1 0 U2 2 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 NOV-DEC PY 1998 VL 28 IS 6 BP 1 EP 18 DI 10.1287/inte.28.6.1 PG 18 WC Management; Operations Research & Management Science SC Business & Economics; Operations Research & Management Science GA 159AG UT WOS:000078149200001 ER PT J AU Shenoy, D Grueneberg, K Naciri, J Shashidhar, R AF Shenoy, D Grueneberg, K Naciri, J Shashidhar, R TI Photo-dimerized monolayer (PDML) versus rubbed polyimide (RPI): A comparison of electro-optic properties SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS LA English DT Article DE liquid crystal display; photo-alignment; monolayer; electro-optic response; anchoring energy ID LIQUID-CRYSTAL DISPLAYS; SURFACE; FILMS; ANGLE; WIDE AB Electro-Optic response characteristics as well as polar anchoring energies of liquid crystal cells prepared using a new photo-alignment technique i.e., photo-dimerized monolayer, have been measured. These data are compared with those for cells that use a rubbed polyimide alignment layer The two alignment methods yield comparable electro-optic properties showing thereby that the new photo-alignment technique is a viable alternative to the rubbed alignment technique for display applications. C1 USN, Res Lab, Geocenters Inc, Washington, DC 20375 USA. RP Shenoy, D (reprint author), USN, Res Lab, Geocenters Inc, Code 6900, Washington, DC 20375 USA. NR 19 TC 27 Z9 27 U1 0 U2 2 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN J9 JPN J APPL PHYS 2 JI Jpn. J. Appl. Phys. Part 2 - Lett. PD NOV 1 PY 1998 VL 37 IS 11A BP L1326 EP L1329 DI 10.1143/JJAP.37.L1326 PG 4 WC Physics, Applied SC Physics GA 139GU UT WOS:000077020600019 ER PT J AU Howard, RM Willson, JG Zgraggen, CJ AF Howard, RM Willson, JG Zgraggen, CJ TI Lift enhancement of a wing/strake configuration using pneumatic blowing SO JOURNAL OF AIRCRAFT LA English DT Article C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Howard, RM (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. NR 8 TC 0 Z9 1 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD NOV-DEC PY 1998 VL 35 IS 6 BP 984 EP 985 DI 10.2514/2.2401 PG 2 WC Engineering, Aerospace SC Engineering GA 148PX UT WOS:000077542000025 ER PT J AU Gao, BC Han, W Tsay, SC Larsen, NF AF Gao, BC Han, W Tsay, SC Larsen, NF TI Cloud detection over the Arctic region using airborne imaging spectrometer data during the daytime SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID WATER-VAPOR BAND; PATTERN-RECOGNITION; COVER ANALYSIS; POLAR-REGIONS; SURFACE; IMAGERY; CLASSIFICATION AB Detection of clouds over arctic regions from current satellite radiometric measurements in the visible and IR atmospheric window regions, such as those of Advanced Very High Resolution Radiometer and Landsat, is often difficult due to the high albedos of snow- and ice-covered surfaces in the visible and the nearly isothermal temperature profiles in the lower atmosphere. In this paper the authors show that the water vapor absorption channel at 1.38 mu m is effective in detecting high clouds over snow- and ice-covered surfaces in the Arctic. Low-level clouds can be detected from surface snow and sea ice using a narrow channel centered at 1.5 mu m with a width of approximately 10 nm because of the dark background that results from strong absorption by snow and sea ice. Imaging data with contiguous spectral coverage between 0.4 and 2.5 mu m acquired with the Airborne Visible/Infrared Imaging Spectrometer during the Arctic Radiation Measurements in Column Atmosphere-Surface System in Alaska in 1995 are analyzed. The authors have observed that as wavelength increases from 1.38 mu m the atmospheric water vapor absorption becomes weaker and weaker and the low-level clouds and surface tundra are increasingly seen. It is always possible to locate a narrow channel in the spectral range of 1.38-1.50 mu m with appropriate water vapor absorption strength to separate water and ice clouds from surface snow, sea ice, and tundra. The simple cloud-masking technique described here is directly applicable to cloud detection during the daytime from hyperspectral imaging data over arctic regions, which will be acquired with future satellite sensors. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. SFA Inc, Largo, MD USA. NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. Univ Alaska, Inst Geophys, Fairbanks, AK USA. Univ Alaska, Dept Phys, Fairbanks, AK USA. RP Gao, BC (reprint author), USN, Res Lab, Remote Sensing Div, Code 7212,4555 Overlook Dr SW, Washington, DC 20375 USA. RI Tsay, Si-Chee/J-1147-2014 NR 24 TC 12 Z9 12 U1 1 U2 2 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 NOV PY 1998 VL 37 IS 11 BP 1421 EP 1429 DI 10.1175/1520-0450(1998)037<1421:CDOTAR>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 144CH UT WOS:000077295800004 ER PT J AU Vurgaftman, I Meyer, JR Hoffman, CA Redfern, D Antoszewski, J Faraone, L Lindemuth, JR AF Vurgaftman, I Meyer, JR Hoffman, CA Redfern, D Antoszewski, J Faraone, L Lindemuth, JR TI Improved quantitative mobility spectrum analysis for Hall characterization SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MAGNETOTRANSPORT CHARACTERIZATION; ELECTRICAL-CONDUCTION; SEMICONDUCTORS AB We present an improved quantitative mobility spectrum analysis (i-QMSA) procedure for determining free electron and hole densities and mobilities from magnetic-field-dependent Hall and resistivity measurements on bulk or layered semiconductor samples. The i-QMSA technique is based on a fundamentally new approach, which optimizes the fit to the conductivity tensor components and their slopes by making those adjustments in the mobility spectra that result in the greatest error reduction. Empirical procedures for manipulating the mobility spectra are also introduced, with the dual purpose of reducing the error of the fit and simplifying the shape of the spectra to minimize the presence of unphysical artifacts. A fully automated computer implementation of the improved QMSA is applied to representative synthetic and real data sets involving various semiconductor material systems. These results show that, as compared with previous approaches, the presented algorithm maximizes the information that may be extracted from a given data set, and is suitable for use as a standard tool in the characterization of semiconductor material and device transport properties. (C) 1998 American Institute of Physics. [S0021-8979(98)07321-6]. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Western Australia, Dept Elect & Elect Engn, Nedlands, WA 6907, Australia. LakeShore Cryotron Inc, Westerville, OH 43082 USA. RP Vurgaftman, I (reprint author), USN, Res Lab, Code 5613, Washington, DC 20375 USA. NR 11 TC 89 Z9 89 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 1998 VL 84 IS 9 BP 4966 EP 4973 DI 10.1063/1.368741 PG 8 WC Physics, Applied SC Physics GA 128VF UT WOS:000076428500046 ER PT J AU Rendell, RW Buot, FA Snow, ES Campbell, PM Park, D Marrian, CRK Magno, R AF Rendell, RW Buot, FA Snow, ES Campbell, PM Park, D Marrian, CRK Magno, R TI Operation and design of metal-oxide tunnel transistors SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB The current-voltage (I-V) characteristics in the ballistic limit of metal-oxide tunnel transistors are calculated as a function of temperature, potential barrier height, gate insulator thickness, aspect ratio, and oxide-channel shape. The saturation ('knee') point and three modes of current transport across the device are discussed. For a given aspect ratio, the output impedance improves with increase in tunnel-oxide width, accompanied by slight decrease of gate transconductance. The net result is a significant improvement in the transistor gain. The gate transconductance improves with decrease in gate-insulator thickness, while approximately maintaining the output impedance. The net result is also a significant improvement in the transistor gain. Thus for a given aspect ratio, further device optimization to increase the transistor gain can be carried out by either increasing the tunnel oxide width or decreasing the gate insulator thickness. In practice, one preferably does both. A numerical study of the device performance of tapered-oxide devices is undertaken. We find that uniform-oxide channel design is generally superior to tapered-oxide channel designs. [S0021-8979(98)02521-3]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rendell, RW (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 6 TC 4 Z9 4 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 1998 VL 84 IS 9 BP 5021 EP 5031 DI 10.1063/1.368749 PG 11 WC Physics, Applied SC Physics GA 128VF UT WOS:000076428500054 ER PT J AU Guha, S AF Guha, S TI Characterization of Si+ ion-implanted SiO2 films and silica glasses SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID VISIBLE-LIGHT EMISSION; POROUS SILICON; QUANTUM CONFINEMENT; NANOCRYSTALS; PHOTOLUMINESCENCE; LUMINESCENCE; SIZE AB We report here electron spin resonance (ESR), Raman scattering, photoluminescence (PL), and absorption studies of Si+ ions implanted into silica glasses and thermally grown SiO2 films on Si wafers. The aim is to understand the defect formation and luminescence mechanism as the films were annealed at several temperatures. In as-grown Si-implanted films, paramagnetic defects in the form of Si-E' and nonbridging oxygen hole centers (NBOHC) were detected by ESR. A luminescence band, centered at 650 nm, was observed in these samples. The E' and NBOHC defects were annealed out in samples annealed above 500 degrees C, but Si dangling bonds in the form of P-b centers were observed. In films annealed above 800 degrees C, Si nanocrystals of varying size between and 5 nm were formed. as detected by transmission electron microscopy. A red PL band (>700 nm) and a Si-phonon band at 510 cm(-1) gradually evolved as a function of anneal temperature. The observation of the Si-phonon mode with a 15 cm(-1) shift in the peak position from the bulk affirms the presence of Si clusters in the annealed ion-implanted SiO2 films and silica glasses. We attribute this red PL band to excitonic recombination in Si nanocrystals. The peak position of this PL band was found to shift with excitation wavelength. The shift of the PL spectra as a function of excitation energy was interpreted as the emission from Si particles of certain sizes that are excited by the incident energy. An energy band gap distribution due to a size distribution was used to model the PL spectra at each excitation energy. (C) 1998 American Institute of Physics. [S0021-8979(98)07121-7]. C1 USN, Res Lab, Div Condensed Matter & Radiat Sci, Washington, DC 20375 USA. RP Guha, S (reprint author), USN, Res Lab, Div Condensed Matter & Radiat Sci, Washington, DC 20375 USA. EM guha@ccf.nrl.navy.mil NR 16 TC 50 Z9 50 U1 2 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 1998 VL 84 IS 9 BP 5210 EP 5217 DI 10.1063/1.368812 PG 8 WC Physics, Applied SC Physics GA 128VF UT WOS:000076428500085 ER PT J AU Callahan, MP AF Callahan, MP TI Burma: The challenge of change in a divided society. SO JOURNAL OF ASIAN STUDIES LA English DT Book Review C1 USN, Postgrad Sch, Washington, DC 20350 USA. RP Callahan, MP (reprint author), USN, Postgrad Sch, Washington, DC 20350 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ASSN ASIAN STUDIES INC PI ANN ARBOR PA UNIV MICH 1 LANE HALL, ANN ARBOR, MI 48109 USA SN 0021-9118 J9 J ASIAN STUD JI J. Asian Stud. PD NOV PY 1998 VL 57 IS 4 BP 1216 EP 1218 DI 10.2307/2659378 PG 3 WC Area Studies; Asian Studies SC Area Studies; Asian Studies GA 158KF UT WOS:000078114100082 ER PT J AU Pope, RK Scheetz, RW AF Pope, RK Scheetz, RW TI Channel catfish virus: interaction with the cytoskeleton SO JOURNAL OF FISH DISEASES LA English DT Article ID HERPES-SIMPLEX VIRUS; NUCLEAR POLYHEDROSIS-VIRUS; INTERMEDIATE FILAMENTS; LIVING CELLS; MICROTUBULES; ACTIN; ORGANIZATION; REPLICATION; TYPE-1; MICROFILAMENTS AB The infection of channel catfish ovarian cells with channel catfish virus results in the redistribution of all cytoskeletal elements during virus-induced syncytium formation. Actin filaments are normally arranged as large stress fibres, even during early stages of infection, but become redistributed as densely staining regions near the centre of the syncytium in latent infection. Microtubules and vimentin filaments (easily visible in early infection) lose all visible organization during syncytium formation. Stabilization of microtubules with taxol results in the production of elongate syncytia with regularly organized microtubules. Conversely, disruption of microtubules with nocodazole inhibits cell fusion and causes a reduction in infectious virus production. This reduction upon treatment with nocodazole, and the subsequent rescue of virus production upon addition of taxol indicates that viral replication relies upon the presence of microtubules. C1 Univ So Mississippi, Hattiesburg, MS 39406 USA. RP Pope, RK (reprint author), USN, Res Lab, Code 7333, Stennis Space Ctr, MS 39529 USA. NR 38 TC 1 Z9 1 U1 0 U2 3 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0140-7775 J9 J FISH DIS JI J. Fish Dis. PD NOV PY 1998 VL 21 IS 6 BP 433 EP 442 DI 10.1046/j.1365-2761.1998.00129.x PG 10 WC Fisheries; Marine & Freshwater Biology; Veterinary Sciences SC Fisheries; Marine & Freshwater Biology; Veterinary Sciences GA 148BB UT WOS:000077531500005 ER PT J AU Slinker, SP Fedder, JA Chen, J Lyon, JG AF Slinker, SP Fedder, JA Chen, J Lyon, JG TI Global MHD simulation of the magnetosphere and ionosphere for 1930-2330 UT on November 3, 1993 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY MAGNETIC-FIELD; EARTHS MAGNETOSPHERE; POTENTIALS; CONVECTION AB Using a, three-dimensional, global MHD simulation of the interaction of the Earth's magnetosphere with the solar wind, we examine the configuration of the magnetosphere and ionosphere during the hours from 1930 to 2330 UT on November 3, 1993. Direct measurements of the solar wind are not available. IMP 8 was in the magnetosheath near the dusk flank, and the simulation was run using LMP 8 measurements as an approximation for the solar wind parameters. The simulation prediction of the field and plasma quantities at the IMP 8 position were then compared with the recorded measurements, leading to a correction to the solar wind input to the simulation. Though this process could be iterated, we stopped after making one correction. The polar cap convection patterns compare well with patterns from the assimilated mapping of ionospheric electrodynamics (AMIE) analysis for this period. However, the MHD simulation predicts much higher cross polar cap potentials. We also examine the magnetopause position at the subsolar region and compare to measurements made by the geosynchronous spacecraft. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Dartmouth Coll, Dept Phys, Hanover, NH 03755 USA. RP Slinker, SP (reprint author), USN, Res Lab, Div Plasma Phys, Code 6794, Washington, DC 20375 USA. NR 8 TC 15 Z9 15 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 1998 VL 103 IS A11 BP 26243 EP 26250 DI 10.1029/97JA02775 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 133UX UT WOS:000076705500005 ER PT J AU Balas, GJ Packard, AK Renfrow, J Mullaney, C M'Closkey, RT AF Balas, GJ Packard, AK Renfrow, J Mullaney, C M'Closkey, RT TI Control of the F-14 aircraft lateral-directional axis during powered approach SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article AB The design of linear controllers for the F-14 aircraft lateral-directional axis during powered approach using the structured singular-value (mu) framework is presented. Controllers are designed for an angle of attack of 10.5 deg and an airspeed of 137 kn, the on-speed flight condition, Each controller is implemented in a simplified nonlinear simulation and the full-order Fortran nonlinear simulation of the F-14, Pilot-in-the-loop simulations are used to verify their performance in the crewed flight simulator at the U.S. Naval Air Warfare Center, Patuxent River, Maryland, The mu controllers out perform the current analog and newly developed digital lateral-directional powered approach flight control system in pilot-in-the-loop simulations. C1 Univ Minnesota, Dept Aerosp Engn & Mech, Minneapolis, MN 55455 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. USN, Naval Air Warfare Ctr, Div Aircraft, Patuxent River, MD USA. Univ Calif Los Angeles, Dept Mech Aerosp & Nucl Engn, Los Angeles, CA 90095 USA. RP Balas, GJ (reprint author), Univ Minnesota, Dept Aerosp Engn & Mech, Minneapolis, MN 55455 USA. EM balas@aem.umn.edu NR 15 TC 15 Z9 18 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD NOV-DEC PY 1998 VL 21 IS 6 BP 899 EP 908 DI 10.2514/2.4323 PG 10 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 139HB UT WOS:000077021500012 ER PT J AU Leggatt, GR Hosmalin, A Pendleton, CD Kumar, A Hoffman, S Berzofsky, JA AF Leggatt, GR Hosmalin, A Pendleton, CD Kumar, A Hoffman, S Berzofsky, JA TI The importance of pairwise interactions between peptide residues in the delineation of TCR specificity SO JOURNAL OF IMMUNOLOGY LA English DT Article ID CYTOTOXIC T-LYMPHOCYTE; CELL RECEPTOR ANTAGONISTS; CLASS-I H-2K(B); VACCINE CONSTRUCTS; NEUTRALIZING ANTIBODY; MOLECULAR ANALYSIS; PARTIAL AGONISTS; VIRAL PEPTIDES; BINDING; ANTIGEN AB A minimal, nonamer epitope (TEMEKEGKI) from the reverse transcriptase protein of HIV-1, restricted by R-2K(k), was identified and the function of individual residues determined. Besides classical anchor residues at positions 2 and 9, methionine at position 3 was identified as an important MWC anchor and improved binding of a different (malarial) nonamer epitope to H-2K(k), albeit while also abolishing CTL recognition. Lysine at position 5 was replaceable by alanine for CTL raised against mild-type peptide but abolished recognition for CTL raised against the variant 5ALA peptide, indicating a unidirectional cross-reactivity, Interestingly, one CTL line raised against the 5ALA substituted peptide was permissive for a double substitution at positions 5 and 6, in which lysine was permissive at position 5 only if the adjacent glutamic acid was replaced by alanine, Extensive analysis revealed three distinct patterns of responses with peptides doubly substituted in this region: recognition of both single substitutions but not the double substitution, recognition of only one single substitution but also the double substitution, or recognition of both single substitutions and the double substitution. A second complementary substitution can therefore restore function lost through a first substitution. Thus, no residue acts independently of its neighbors, and pairs of substitutions may give results not predictable from the effects of each taken singly. This finding may have bearing on viral infections (such as HIV), in which the accumulation of two mutations in the epitope may lead to the reengagement of memory CTL previously silenced by the initial mutation. C1 NCI, Mol Immunogenet & Vaccine Res Sect, Metab Branch, NIH, Bethesda, MD 20892 USA. USN, Med Res Inst, Malaria Program, Bethesda, MD 20889 USA. RP Berzofsky, JA (reprint author), NCI, Mol Immunogenet & Vaccine Res Sect, Metab Branch, NIH, Bldg 10,Room 6B-12, Bethesda, MD 20892 USA. RI Leggatt, Graham/G-1924-2010; OI Leggatt, Graham/0000-0002-4078-5653 NR 46 TC 21 Z9 22 U1 0 U2 0 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD NOV 1 PY 1998 VL 161 IS 9 BP 4728 EP 4735 PG 8 WC Immunology SC Immunology GA 131NA UT WOS:000076581100038 PM 9794403 ER PT J AU Eckman, JE Duggins, DO AF Eckman, JE Duggins, DO TI Larval settlement in turbulent pipe flows SO JOURNAL OF MARINE RESEARCH LA English DT Article ID BENTHIC SUSPENSION FEEDERS; POPULATION-DYNAMICS; HYDRODYNAMICAL PROCESSES; VERTICAL-DISTRIBUTION; INVERTEBRATE LARVAE; BOUNDARY-LAYER; MARINE; RECRUITMENT; BARNACLE; BOTTOM AB In two experiments, larval settlement was studied within a series of pipes, each containing steady, turbulent, flowing seawater. The study was designed to determine effects of flow (speed, turbulence intensity and wall shear stress) and surface orientation on rates of settlement of larvae of various taxa, and to relate variability in patterns of settlement among orientations and flows to the concomitant variability expected in rates of larval supply or delivery to the pipe walls. Patterns of settlement of all five taxa (the barnacle Balanus spp., the mussel Mytilus trossulus, the serpulid polychaete Pseudochitinopoma occidentalis, the cyclostome bryozoan Tubulipora sp., and the terebellid polychaete Eupolymnia heterobranchia) generally conformed to predicted patterns of larval supply to pipe walls (the larval transport flux). Within each taxon results were consistent in the two experiments. For these taxa, the transport fluxes that most closely matched observed settlement fluxes were predicted by assuming that larvae exhibited average speeds of advection (by swimming or sinking) of comparatively low magnitude. These best-fit larval speeds are consistent with results from previous studies of larval swimming. However, some results indicate that settlement patterns also were affected significantly by processes operating after larval contact with pipe walls. In several instances settlement patterns exhibited a strong and significant effect of wall orientation that varied in intensity with flow speed in a manner not predictable from expected patterns of larval supply. The probable causes for this effect and statistical interaction vary among taxa, but in all cases involve consideration of the habitat, behavior or success of the post-settlement, benthic individual. C1 Skidaway Inst Oceanog, Savannah, GA 31411 USA. Friday Harbor Labs, Friday Harbor, WA 98250 USA. RP Off Naval Res, Code 322BC,800 N Quincy St, Arlington, VA 22217 USA. NR 79 TC 21 Z9 23 U1 1 U2 5 PU SEARS FOUNDATION MARINE RESEARCH PI NEW HAVEN PA YALE UNIV, KLINE GEOLOGY LAB, 210 WHITNEY AVENUE, NEW HAVEN, CT 06520-8109 USA SN 0022-2402 EI 1543-9542 J9 J MAR RES JI J. Mar. Res. PD NOV PY 1998 VL 56 IS 6 BP 1285 EP 1312 DI 10.1357/002224098765093643 PG 28 WC Oceanography SC Oceanography GA 153VV UT WOS:000077854500005 ER PT J AU Batteen, ML Butler, CL AF Batteen, ML Butler, CL TI Modeling studies of the Leeuwin Current off Western and Southern Australia SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID CALIFORNIA CURRENT SYSTEM; OCEAN CIRCULATION; EDDIES; COAST AB The Leeuwin Current strengthens considerably from February to May each year, following the slackening of southerly coastal winds; strong eddies develop. A high-resolution, multilevel, primitive equation ocean model is used to examine this eddy development in an idealized way, by considering the development of how from rest when temperatures are initially given the observed longshore gradients. The system is allowed to geostrophically adjust in the absence of longshore winds and of any surface heat flux. Two types: of experiments are conducted. The first type uses the Indian Ocean climatological temperature gradient forcing (case 1 and 2), while the second type repeats the first experiment with the added contribution of the North West Shelf (NWS) temperature profile (cases 3 and 4). To investigate the additional effects of coastline irregularities, cases 1 and 3 use an ideal coastline, while cases 2 and use an irregular (realistic) coastline. In all cases, maximum surface velocities occur at Cape Leeuwin, where the Leeuwin Current changes direction and off Southern Australia. Maximum undercurrent velocities occur off Western Australia. in case 1, Cape Leeuwin and the Western Australian coast are the preferred locations for the development of warm, anticyclonic eddies, which are generated due to a mixed instability mechanism. In case 2, the warm, anticyclonic eddies occur in the vicinity of coastal promontories and at Cape Leeuwin. While advection of warm water is present along the entire coast in case 1, the irregular coastline geometry limits the extent of warm water in case 2. The added contribution from the NWS water in cases 3 and 3 augments the onshore geostrophic inflow to produce a model Leeuwin Current and undercurrent that are more vigorous and unstable than in the previous cases. In case 3, the NWS water adds strong horizontal shear to the coastal equatorial region of the domain and vertical shear to the inshore current. It also advects warmer water along the entire coast. In case 4, the addition of both the NWS water and the irregular coastline results in the establishment of a stronger surface current and undercurrent than in the previous cases; however, the irregular coastline limits the extent of the advection of the NWS warmer water along the Australian coast. In all cases, warm, anticyclonic eddies develop at the coast. Cold, cyclonic eddies form from the limbs of the established warm, anticyclonic eddies with the result that two counterrotating cells are developed. Once the eddy pairs begin their westward propagation, the Leeuwin Current intensifies as nonlinear effects result in a jet between the eddies and the coast. These effects translate downstream to augment the current velocities at the coast, which, due to a mixed instability mechanism, result in the development of new anticyclonic eddies at the coast. The results from case 4, which has the most realistic features, highlights the major characteristics of the Leeuwin Current and agrees well with available observations. These results show that the model successfully captures the qualitative nature of the nonlinear, eddying response of the Leeuwin Current. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP USN, Postgrad Sch, Dept Oceanog, Code OC-Bv, Monterey, CA 93943 USA. EM batteen@oc.nps.navy.mil NR 37 TC 16 Z9 16 U1 0 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 EI 1520-0485 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD NOV PY 1998 VL 28 IS 11 BP 2199 EP 2221 DI 10.1175/1520-0485(1998)028<2199:MSOTLC>2.0.CO;2 PG 23 WC Oceanography SC Oceanography GA 145JL UT WOS:000077367400007 ER PT J AU Kenney, R Richards, MW AF Kenney, R Richards, MW TI Photoelastic stress patterns produced by implant-retained overdentures SO JOURNAL OF PROSTHETIC DENTISTRY LA English DT Article ID DESIGNS AB Statement of problem. When 2 implants are used to support a removable overdenture, optimal stress distribution to minimize forces to the implants is desired. Purpose. This study used photoelastic analysis to compare the stress patterns generated around implants with 2 retention mechanisms. Material and methods. Two root form implants were anchored in a photoelastic mandible and a removable overdenture was fabricated. The denture was lined with a resilient layer of impression material to simulate oral mucosa. Attachment of the denture to the implants was varied by using ball/O-ring and bar-clip attachments. Vertical and oblique occlusal forces from 10 to 200 lb were applied unilaterally to the right and left first molars. Resultant stress distributions in the photoelastic mandible were photographed and evaluated. Results. With vertical forces, the ball/O-ring attachment transferred minimal stress to both implants. Vertical forces applied to the bar-clip overdenture created immediate stress patterns of greater magnitude and concentration on both implants. A posterior oblique load resulted in similar stress patterns to both systems with slightly greater stress to the bar-clip overdenture. Conclusions. Within the limits of this study, ball/O ring attachments transferred less stress to implants than the bar-clip attachments when the photoelastic model was subjected to a posterior vertical load. C1 W Virginia Univ, Sch Dent, Dept Restorat Dent, Morgantown, WV 26506 USA. USN Hosp, Portsmouth, VA USA. USN, Dent Corps, Washington, DC USA. RP Richards, MW (reprint author), W Virginia Univ, Sch Dent, Dept Restorat Dent, POB 9495, Morgantown, WV 26506 USA. NR 21 TC 58 Z9 64 U1 0 U2 1 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0022-3913 J9 J PROSTHET DENT JI J. Prosthet. Dent. PD NOV PY 1998 VL 80 IS 5 BP 559 EP 564 DI 10.1016/S0022-3913(98)70032-0 PG 6 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 137BN UT WOS:000076894100008 PM 9813806 ER PT J AU Park, SY AF Park, SY TI Launch vehicle trajectories with a dynamic pressure constraint SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID VARIABLE INEQUALITY CONSTRAINTS AB The problem of three-dimensional launch trajectories for the advanced launch system to minimize fuel or equivalently maximize payload is considered. A dynamic pressure inequality constraint is involved due to its significance on the resulting trajectories and structure of the launch vehicle. Highly accurate solutions and exact switching structures of the optimal trajectories are presented by using a multiple shooting method. The multiple shooting structure is modified to satisfy the internal boundary conditions and discontinuities in variables at entry and exit points of the boundary are. A methodology is also developed to visualize the optimal controls in a geometric sense using hodograph analysis. C1 Texas A&M Univ, Dept Aerosp Engn, College Stn, TX 77843 USA. RP Park, SY (reprint author), USN, Dept Aeronaut & Astronaut, Postgrad Sch, Monterey, CA 93943 USA. RI Park, Sang-Young/F-5989-2013 NR 18 TC 2 Z9 2 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD NOV-DEC PY 1998 VL 35 IS 6 BP 765 EP 773 DI 10.2514/2.3414 PG 9 WC Engineering, Aerospace SC Engineering GA 156HZ UT WOS:000077996700007 ER PT J AU Mandell, AJ Selz, KA Shlesinger, MF AF Mandell, AJ Selz, KA Shlesinger, MF TI Transformational homologies in amino acid sequences suggest memberships in protein families SO JOURNAL OF STATISTICAL PHYSICS LA English DT Article DE protein physics; wavelets; hydrophobic free energy eigenfunctions; maximum entropy power spectra ID HYDROPHOBIC FREE-ENERGY; GLOBULAR PROTEINS; DYNAMICS; WATER; RECOGNITION; CHARACTER; MEMBRANE; BEHAVIOR; RESIDUES; SYSTEMS AB The 20 amino acid monomers composing polymeric proteins ale encoded using their individual properties relatable to thermodynamic potentials such as aqueous partial specific volumes, aqueous molar volumes, and free energies of transfer from hydrocarbon to water solvents. These principally hydrophobic solvation, "hydrophobicity"-derived free energies are minimized in protein folding as well as protein-protein and peptide-receptor interactions. Sequential patterns in the one-dimensional distribution of these energies, reflected in dominant wavelengths of amino acid hydrophobicity, and the locations of singular; hierarchical, secondary and supersecondary structures are elucidated by orthogonal decomposition and eigenfunction construction followed by continuous wavelet and all poles, maximum entropy power spectral transformations. The resulting graphs discriminate among examples of structural families of proteins. C1 Emory Univ, Cielo Inst, Asheville, NC 28804 USA. Florida Atlantic Univ, Dept Math, Boca Raton, FL 33431 USA. Off Naval Res, Div Phys Sci, Arlington, VA 22217 USA. RP Mandell, AJ (reprint author), Emory Univ, Cielo Inst, Asheville, NC 28804 USA. NR 65 TC 7 Z9 7 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-4715 J9 J STAT PHYS JI J. Stat. Phys. PD NOV PY 1998 VL 93 IS 3-4 BP 673 EP 697 DI 10.1023/B:JOSS.0000033248.97129.3f PG 25 WC Physics, Mathematical SC Physics GA 155KU UT WOS:000077946500017 ER PT J AU Couchman, LS Roy, DNG Warner, J AF Couchman, LS Roy, DNG Warner, J TI Inverse Neumann obstacle problem SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SCATTERING; DOMAIN AB Results are reported for direct and inverse scattering of plane acoustic waves from sound-hard scatterers of arbitrary shapes in an infinite, homogeneous ambience. The direct problem is solved via a shape deformation technique which is valid for finite deformations. The resulting solution requires solving only a set of algebraic recursion relations, but neither integral equations nor Green's function. The methodology has three essential features: all calculations refer exclusively to a known simple boundary Gamma(s) instead of the iteratively updated scatterer shapes; the Jacobian of the scattered field is evaluated by solving a series of Helmholtz's equations (with different boundary data) in the region exterior to the simple shape Gamma(s); and no ambiguity in the solution arises due to the interior eigenvalues. The inverse problem of recovering the scatterer boundary shape is solved by least square minimization using the Levenberg-Marquardt algorithm. Inversions of several two-dimensional shapes with varying degrees of complexity are reported. The procedures described generalize straightforwardly to transmission and three-dimensional problems. (C) 1998 Acoustical Society of America. [S0001-4966(98)06111-6]. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Landover, MD 20785 USA. RP Couchman, LS (reprint author), USN, Res Lab, Code 7130,4555 Overlook Ave, Washington, DC 20375 USA. NR 10 TC 11 Z9 12 U1 0 U2 0 PU ACOUSTICAL SOC AMER AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0001-4966 EI 1520-8524 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1998 VL 104 IS 5 BP 2615 EP 2621 DI 10.1121/1.423845 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 136RM UT WOS:000076873000008 ER PT J AU Maidanik, G Becker, KJ AF Maidanik, G Becker, KJ TI Noise control of a master harmonic oscillator coupled to a set of satellite harmonic oscillators SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID STRUCTURAL FUZZY AB The overall gain is defined as the ratio of the stored energy in the isolated master harmonic oscillator to that in the coupled one. This gain is composed of two distinct factors: The first factor, the external input power gain, relates to the ratio of the external input power into the isolated master harmonic oscillator to that into the coupled one. The second factor, the loss factor gain, relates to the ratio of the loss factor of the coupled master harmonic oscillator to that of the isolated master harmonic oscillator. Both loss factors are in reference to the stored energy in the master harmonic oscillator only. It has been customary to assume the first factor to be unity and, thus the overall gain and the loss factor gain have been assumed to be identical. It is argued here that often this assumption is not valid. Therefore, noise control measures that are based on this assumption may have been wrongly evaluated. A few examples that illustrate the disparity between the overall gain and the loss factor gain are cited in this paper. [S0001-4966(98)03111-7]. C1 USN, Ctr Surface Warfare, Carderock Div, DTMB, W Bethesda, MD 20817 USA. RP Maidanik, G (reprint author), USN, Ctr Surface Warfare, Carderock Div, DTMB, 9500 MacArthur Blvd, W Bethesda, MD 20817 USA. NR 17 TC 18 Z9 18 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1998 VL 104 IS 5 BP 2628 EP 2637 DI 10.1121/1.423846 PG 10 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 136RM UT WOS:000076873000010 ER PT J AU Piquette, JC Forsythe, SE AF Piquette, JC Forsythe, SE TI Generalized material model for lead magnesium niobate (PMN) and an associated electromechanical equivalent circuit SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB An existing one-dimensional nonlinear material model of lead magnesium niobate [J. C. Piquette and S. E. Forsythe, "A nonlinear model of lead magnesium niobate (PMN)," J Acoust. Sec. Am. 101, 289-296 (1997)] is generalized to three dimensions. The resulting theory is applied to two practical systems: the "thickness expander plate" and the "length expander bar." Linearizing the theory results in an electromechanical equivalent circuit that is applicable to predicting the first-order behavior of transducers based on either of these practical systems. The methods used are sufficiently general that the circuit is also appropriate for piezoelectric, and even for electrostatic, transducers. Preliminary experimental data that confirm the validity of the circuit are presented. Connections between the constants of the theory and those of piezoelectricity are derived, and a general expression for the coupling coefficient is obtained. Known theoretical coupling coefficients for piezoelectric and electrostatic transducers are recovered as special cases. The coupling coefficient of the PMN bar at zero prestress and zero remanent polarization is examined in some detail. For this case it is found that, to a good approximation, the bias voltage of the optimal (i.e., maximum) coupling coefficient is root 2 times the bias voltage which produces the maximum effective piezoelectric d(33) A Simple formula for estimating second harmonic distortion at zero stress and remanent polarization is given. The D field for the bar is obtained in terms of a Maclaurin series in stress. This series is asymptotic in the electric field, and is useful for estimating harmonic distortion when the stress or remanent polarization are nonzero. [S0001-4966(98)00911-4]. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. RP Piquette, JC (reprint author), USN, Undersea Warfare Ctr, 1176 Howell St, Newport, RI 02841 USA. NR 11 TC 17 Z9 18 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1998 VL 104 IS 5 BP 2763 EP 2772 DI 10.1121/1.423861 PG 10 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 136RM UT WOS:000076873000025 ER PT J AU Royston, TJ Houston, BH AF Royston, TJ Houston, BH TI Modeling and measurement of nonlinear dynamic behavior in piezoelectric ceramics with application to 1-3 composites SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID ZIRCONATE-TITANATE CERAMICS; TERFENOL-D; ELECTROACOUSTIC TRANSDUCERS; FERROELECTRIC CERAMICS; PIEZOCERAMIC ACTUATORS; TEMPERATURE-DEPENDENCE; MULTIFIELD ACTUATIONS; HARMONIC DISTORTION; DOMAIN-WALL; VIBRATION AB The nonlinear vibratory behavior of a 1-3 piezoceramic composite is characterized theoretically and experimentally. The developed theoretical model for the electroelastic behavior of the 1-3 composite follows conventional assumptions made by prior investigators but includes nonlinear terms to account for hysteresis in the embedded PZT phase. Experimental measurements of the quasistatic and dynamic mechanical response of the 1-3 with embedded PZT-4 or PZT-5H phases to harmonic electrical excitation over a range of excitation frequencies and two different mechanical lending conditions quantify the nature and level of nonlinearity and illustrate its dependence on the type of PZT material and the mechanical coupling conditions of the 1-3 to its surroundings. Good agreement exists between theoretical predictions and experimental measurements. (C) 1998 Acoustical Society of America. [S0001-4966(98)03211-1] C1 Univ Illinois, Chicago, IL 60607 USA. USN, Res Lab, Washington, DC 20375 USA. RP Royston, TJ (reprint author), Univ Illinois, Chicago, IL 60607 USA. EM troyston@uic.edu RI Royston, Thomas/C-1285-2008 NR 68 TC 29 Z9 32 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1998 VL 104 IS 5 BP 2814 EP 2827 DI 10.1121/1.423866 PG 14 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 136RM UT WOS:000076873000031 ER PT J AU Williams, EG AF Williams, EG TI Supersonic acoustic intensity on planar sources SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The concept of supersonic acoustic intensity was developed in 1995 out of a need to locate the sources of radiation on an internally excited, submerged cylindrical shell. Supersonic intensity is obtained through signal processing of near-field holographic data to remove the subsonic part of the helical or plane wave spectrum, leaving only the radiating components. This eliminates the out-of-plane circulation of the acoustic intensity vector which results from evanescent waves. The resulting supersonic intensity on the surface is generally only positive, representing outgoing power flow from the surface. Since negative intensity regions of a vibrator are removed, sources of radiation are readily located on the surface of the vibrator. Since the earlier work concentrated on a cylindrical geometry, the theory is presented here for a planar geometry. In many ways the theory for the planar case is simpler and more straightforward. Numerical examples are given for simply supported, baffled plates. It is shown how the supersonic intensity reconstructions, and resulting location of radiating source regions are consistent with the popular theories of corner and edge mode radiation from plates. [S0001-4966(98)05810-X] C1 USN, Res Lab, Washington, DC 20375 USA. RP Williams, EG (reprint author), USN, Res Lab, Code 7137, Washington, DC 20375 USA. NR 8 TC 23 Z9 23 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1998 VL 104 IS 5 BP 2845 EP 2850 DI 10.1121/1.423868 PG 6 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 136RM UT WOS:000076873000034 ER PT J AU Wagstaff, RA AF Wagstaff, RA TI The Wagstaff's integration silencing processor filter: A method for exploiting fluctuations to achieve improved sonar signal processor performance SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SCATTERING; SURFACE; WATER AB There is a class of signal processing algorithms that achieves gain by exploiting the amplitude fluctuations in the spectrum analyzed acoustic power. One of those processors is presented. The causes of fluctuations that influence the performance of such processors are discussed, and processed results from a fluctuation-based processor are presented. Gains relative to the average power processor in signal-to-noise ratio (SNR) of as much as 10 dB, and gains in spatial and spectral resolution, minimum detectable levels, and other measures of processor performance have been achieved. For the most part, the additional gains from exploiting fluctuations are independent of the frequency resolution and the array aperture (or number of elements if the noise is "white") and depend on the number of averages and percent of overlap of consecutive time-to frequency fast Fourier transforms (FFT). [S0001-4966(98)00511-6] C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Wagstaff, RA (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 18 TC 7 Z9 9 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1998 VL 104 IS 5 BP 2915 EP 2924 DI 10.1121/1.423875 PG 10 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 136RM UT WOS:000076873000042 ER PT J AU Chun, ST Choe, JY Boulais, KA AF Chun, ST Choe, JY Boulais, KA TI Formalism for rotating electron beams from cusp and compression fields SO JOURNAL OF THE KOREAN PHYSICAL SOCIETY LA English DT Article ID PENIOTRON INTERACTIONS; GENERATION; GYROTRONS AB The dynamics of a relativistic electron beam is analyzed for an arbitrary magnetic field in an axisymmetric system, including a magnetic cusp. The analysis is based on a model utilizing stratified magnetic fields and yields simple algebraic equations for the electron beam parameters. The equations are then applied to a magnetic field profile appropriate for the cusptron or the peniotron microwave tubes which include magnetic compression in the downstream region. By virtue of the stratified model, any experimentally realizable magnetic field can easily be incorporated into the analysis. The analysis also clarifies non-adiabatic phenomena which may occur in these devices as streaming electrons are turned into an axis-rotating electron beam by a magnetic cusp or as the beam is compressed in a relatively short distance. Emphasis is given to the extent of this nonadiabaticity, which contributes to off-centering of the guiding center in the downstream region of the devices. C1 Eulji Med Coll, Div Phys, Taejon 301112, South Korea. USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Chun, ST (reprint author), Eulji Med Coll, Div Phys, Taejon 301112, South Korea. NR 11 TC 0 Z9 0 U1 0 U2 0 PU KOREAN PHYSICAL SOC PI SEOUL PA 635-4, YUKSAM-DONG, KANGNAM-KU, SEOUL 135-703, SOUTH KOREA SN 0374-4884 J9 J KOREAN PHYS SOC JI J. Korean Phys. Soc. PD NOV PY 1998 VL 33 IS 5 BP 571 EP 578 PG 8 WC Physics, Multidisciplinary SC Physics GA 140AF UT WOS:000077062800009 ER PT J AU Swanson, TB Asgeirsson, D Behr, JA Gorelov, A Melconian, D AF Swanson, TB Asgeirsson, D Behr, JA Gorelov, A Melconian, D TI Efficient transfer in a double magneto-optical trap system SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID ATOMIC-BEAM; VAPOR CELL; FUNNEL; CONDENSATE; COLLISIONS AB We demonstrate the transfer of potassium atoms from a vapor-cell type magneto-optical trap (MOT) to a second MOT up to 75 cm away with the use of a spatially narrow push laser that generates a 40-m/s atomic beam. By adding two-dimensional MOT's (atomic funnels) along the transfer path to generate transverse cooling and compression of the beam, we can consistently transfer 78 +/- 10% of the atoms. (C) 1998 Optical Society of America [S0740-3224(98)01711-1] OCIS codes: 020.7010, 140.3320. C1 Tri Univ Meson Facil, Vancouver, BC V6T 2A3, Canada. Simon Fraser Univ, Dept Chem, Burnaby, BC V5A 1S6, Canada. Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. RP Swanson, TB (reprint author), USN Observ, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. RI Melconian, Dan/A-1331-2011 OI Melconian, Dan/0000-0002-0142-5428 NR 27 TC 26 Z9 27 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD NOV PY 1998 VL 15 IS 11 BP 2641 EP 2645 DI 10.1364/JOSAB.15.002641 PG 5 WC Optics SC Optics GA 136NF UT WOS:000076865100001 ER PT J AU Fonseca, P AF Fonseca, P TI Catamenial pneumothorax: A multifactorial etiology SO JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY LA English DT Article C1 USN, Med Ctr, Dept Cardiothorac Surg, Bethesda, MD 20814 USA. RP Fonseca, P (reprint author), USN, Med Ctr, Dept Cardiothorac Surg, 8901 Wisconsin Ave, Bethesda, MD 20814 USA. NR 8 TC 25 Z9 27 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0022-5223 J9 J THORAC CARDIOV SUR JI J. Thorac. Cardiovasc. Surg. PD NOV PY 1998 VL 116 IS 5 BP 872 EP 873 DI 10.1016/S0022-5223(98)00434-6 PG 2 WC Cardiac & Cardiovascular Systems; Respiratory System; Surgery SC Cardiovascular System & Cardiology; Respiratory System; Surgery GA 133NU UT WOS:000076693300038 PM 9806395 ER PT J AU Perkins, FK Marrian, CRK Peckerar, MC AF Perkins, FK Marrian, CRK Peckerar, MC TI Improving pattern placement using through-the-membrane signal monitoring SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 42nd International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication (EIPBN) CY MAY 26-29, 1998 CL CHICAGO, ILLINOIS ID BEAM LITHOGRAPHY AB We describe here a means of improving pattern placement accuracy in the electron-beam lithographic manufacture of membrane masks. Our method is based on collection of the beam transmitted through the membrane with a detector fixed to the mask assembly. A fiducial grid overlaid onto the detector is used to provide a global reference for measurement of the beam position during lithographic patterning. We give results from-recent experiments with components of such a system, and estimate I sigma accuracy in our method to be on the order of 1.5 nm. We discuss the effect of beam scattering on our technique, and possible improvements in our implementation. [S0734-211X(98)03606-3]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Perkins, FK (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM perkins@estd.nrl.navy.mil NR 12 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 1998 VL 16 IS 6 BP 3567 EP 3571 DI 10.1116/1.590499 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 148QA UT WOS:000077542300124 ER PT J AU Dobisz, EA Brandow, SL Bass, R Shirey, LM AF Dobisz, EA Brandow, SL Bass, R Shirey, LM TI Nanolithography in polymethylmethacrylate: An atomic force microscope study SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 42nd International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication (EIPBN) CY MAY 26-29, 1998 CL CHICAGO, ILLINOIS ID RESIST AB This work addresses the formation and development of very dense nanolithographic resolution patterns in polymethylmethacrylate (PMMA) of two molecular weights (MWs), 950 and 50 K. The patterns were lithographically defined by a JEOL JBX-5DII e-beam lithography system operated at 50 kV with a Gaussian probe standard deviation of 8-10 nm. The lithographic patterns consisted of pads of widths from 1 to 20 mu m with a 50 nm gap of exposure in the center and single pass line gratings of periods 40, 60, 80, and 100 nm. Atomic force microscope images were acquired. Latent images of the 50 nm gap were observed over a much larger range in dose and pad size, than observed in developed samples. The morphologies of the two unpatterned resists were comparable exhibiting a granular type structure with average particle diameters of 52-53 nm and root mean square surface roughness of 0.2-0.3 nm. In developed patterns, the morphologies and resolution of the two MW resists were very different. The 950 K resist exhibited better resolution and contrast than the 50 K resist. The results are discussed in the context of the exposure and development of macromolecular resists. [S0734-211X(98)14606-1]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Dobisz, EA (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM dobisz@estd.nrl.navy.mil RI Shirey, Loretta/B-3164-2013 OI Shirey, Loretta/0000-0003-2600-3405 NR 14 TC 12 Z9 13 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 1998 VL 16 IS 6 BP 3695 EP 3700 DI 10.1116/1.590501 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 148QA UT WOS:000077542300148 ER PT J AU Dobisz, EA Fedynyshyn, TN Ma, D Shirey, LM Bass, R AF Dobisz, EA Fedynyshyn, TN Ma, D Shirey, LM Bass, R TI Electron-beam nanolithography, acid diffusion, and chemical kinetics in SAL-601 SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 42nd International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication (EIPBN) CY MAY 26-29, 1998 CL CHICAGO, ILLINOIS ID SCANNING TUNNELING MICROSCOPE; AMPLIFIED RESIST; NEGATIVE PHOTORESISTS; LITHOGRAPHY; RESOLUTION; REDUCTION AB The work presents a unique investigation of the role of postexposure bake (PEB) on resist insolubility, FEB reaction kinetics, and the high resolution behavior of Microposit(TM) SAL-601. Patterns of 20-100 mu m rectangles and single pass isolated lines were written on a JEOL JBX-5DII e-beam lithography system operated at 50 kV. The effects of FEB temperatures of 90-110 degrees C for periods of 1-11 min on resist insolubility and linewidth were examined. The samples were developed in MF-322 or acetone. The range of patterns allowed measurement of both the resist exposure curves and the line spread for each FEB condition. Insolubility in MF-322 can result from protection reactions and/or crosslinking reactions. Acetone insolubility, a characteristic of crosslinked resist, was observed at FEB temperatures of 100 degrees C and above. At 90 degrees C,: acetone insolubility (crosslinking) was observed only after a FEB of 11 min. From the resist exposure curves for a sequence of FEB times, reaction orders for the FEB processes that led to resist insolubility were determined. At temperatures of 100-110 degrees C, reaction orders of 2.4 and 2.1 were obtained for reactions that led to insolubility in MF-322 and acetone, respectively. At 90 degrees C the order of reaction leading to MF-322 insolubility was 1.8. PEBs at 90 degrees C for 3 and 6 min produced the finest lines, with linewidths less than or equal to 50 nm over an order of magnitude range in dose. An acid diffusion mth order reaction model, which allows for H+ loss to the surface, was introduced to analyze the linewidth measurements. In the 105-110 degrees C temperature range, the model best fit the data with diffusion coefficients-of 4-8 nm(2)/s and acid loss rates of 0.003-0.005%/s. (C) 1998 American Vacuum Society. [S0734-211X(98)03006-6]. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. Shipley Co, Marlborough, MA 01752 USA. RP Dobisz, EA (reprint author), USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RI Shirey, Loretta/B-3164-2013 OI Shirey, Loretta/0000-0003-2600-3405 NR 18 TC 14 Z9 14 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 1998 VL 16 IS 6 BP 3773 EP 3778 DI 10.1116/1.590405 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 148QA UT WOS:000077542300163 ER PT J AU Wang, W McCarthy, D Park, D Ma, D Marrian, C Peckerar, M Goldsman, N Melngailis, J Berry, IL AF Wang, W McCarthy, D Park, D Ma, D Marrian, C Peckerar, M Goldsman, N Melngailis, J Berry, IL TI Fabrication and characterization of buried subchannel implant n-metal-oxide-semiconductor transistors SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 42nd International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication (EIPBN) CY MAY 26-29, 1998 CL CHICAGO, ILLINOIS ID MOSFETS; SOI AB The shrinking of the gate length is not only a challenge for lithography but also for device performance. Subthreshold current increases, so short channel transistors are hard to turn off. In order to reduce the subthreshold current, transistors with buried subchannel implants were modeled and then fabricated by a self-aligned process. This article describes the buried implant metaloxide-semiconductor held effect transistor (MOSFET) model, fabrication, and measured performance. The simple analytic model developed predicts less short channel effects in the buried implant MOSFETs. A novel self-aligned process has, been applied to fabricate the subchannel implants directly under the gate. Identical devices of various gate lengths down to 0.25 mu m were fabricated with and without the buried p(+) implant. The devices with the p(+) implant exhibited a slower threshold voltage roll-off and less subthreshold swing. (C) 1998 American Vacuum Society. [S0734-211X(98)18206-9]. C1 Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. DOD, Microelect Res Lab, Columbia, MD 21045 USA. RP Wang, W (reprint author), Adv Micro Devices Inc, Log Technol Grp, M-S 79,POB 3453, Sunnyvale, CA 94088 USA. NR 5 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 1998 VL 16 IS 6 BP 3812 EP 3816 DI 10.1116/1.590414 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 148QA UT WOS:000077542300171 ER PT J AU Park, D Marrian, CRK Gammon, D Bass, R Isaacson, P Snow, E AF Park, D Marrian, CRK Gammon, D Bass, R Isaacson, P Snow, E TI Small aperture fabrication for single quantum dot spectroscopy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 42nd International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication (EIPBN) CY MAY 26-29, 1998 CL CHICAGO, ILLINOIS AB A simple fabrication method for submicron diameter metallic apertures using negative electron beam resist and metal lift-off has been developed. In general, the lift-off process is beneficial for semiconductor quantum dot spectroscopy, since the original surface condition of the substrate is not altered or destroyed as it may be in a conventional dry or wet etching processes to form apertures in a subtractive process. With an optimum combination of process parameters, such as higher pre- and postexposure bake temperatures for longer times, longer developing time and with optimal mixtures of developers, high aspect ratio resist posts were obtained. Using 20 kV single dot e-beam exposure, a reentrant profile can be obtained directly. While this profile is not obtained with 50 kV single dot e-beam exposure, a higher aspect ratio (similar to 7:1) and sub-100 nm diam resist posts are possible. High vertical sidewall 100 nm diam resist posts are obtained using 50 kV area e-beam exposures. Taking advantage of these characteristics: high aspect ratio, high vertical resist sidewall, and resist undercut at the bottom of post, sub-100 nm diam apertures in 100 nm thick metallic films are obtained by evaporation of metal on the sample and dissolving the resist post in solvent. For sub-100 nm apertures, a significant improvement in aperture edge smoothness was achieved by applying an oxygen plasma. (C) 1998 American Vacuum Society. [S0734-211X(98)06606-2]. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RP Park, D (reprint author), USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. NR 8 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 1998 VL 16 IS 6 BP 3891 EP 3893 DI 10.1116/1.590429 PG 3 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 148QA UT WOS:000077542300187 ER PT J AU Bosse, A Tasker, F Fisher, S AF Bosse, A Tasker, F Fisher, S TI Real-time modal parameter estimation using subspace methods: Applications SO MECHANICAL SYSTEMS AND SIGNAL PROCESSING LA English DT Article AB This article describes the underlying theory and hardware implementation of a newly developed algorithm for online modal parameter identification. An online modal parameter estimation algorithm using subspace methods is applied to both model and experimental data for a 4-m laboratory truss structure. Experimental evaluation of this algorithm demonstrates that the technique accomplishes the objective of tracking multiple modes of a complex dynamical system using multiple sensors. The time-varying behaviour is captured in real time via a graphical display of the frequencies and damping ratios of the system. It is shown that the recursive algorithm provides results similar to the batch algorithm for a time-invariant system. In addition, it is shown that the batch algorithm used to derive the recursive algorithm performs similarly to a newly derived batch algorithm that is closely related to the Eigensystem Realization Algorithm. Details concerning the digital signal processor implementation and off-line monitoring are also presented. (C) 1998 Academic Press. C1 USN, Res Lab, Spacecraft Engn Dept, Washington, DC 20375 USA. RP Bosse, A (reprint author), USN, Res Lab, Spacecraft Engn Dept, Code 8221, Washington, DC 20375 USA. NR 4 TC 13 Z9 17 U1 0 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0888-3270 J9 MECH SYST SIGNAL PR JI Mech. Syst. Signal Proc. PD NOV PY 1998 VL 12 IS 6 BP 809 EP 823 DI 10.1006/mssp.1998.0162 PG 15 WC Engineering, Mechanical SC Engineering GA 139WL UT WOS:000077054200006 ER PT J AU McKinnon, BJ Lassen, LF AF McKinnon, BJ Lassen, LF TI Naproxen-associated sudden sensorineural hearing loss SO MILITARY MEDICINE LA English DT Article ID OTOTOXICITY AB Naproxen is a commonly used nonsteroidal anti-inflammatory drug (NSAID) whose side effects include tinnitus and transient hearing loss. Sudden sensorineural hearing loss has rarely been reported as a result of NSAID use. This usually occurs in patients taking other ototoxic medications, with poor renal function, or with autoimmune disease. This article reports the case of an otherwise healthy patient who experienced permanent sensorineural hearing loss after a brief course of naproxen and reviews the literature on NSATD-related permanent sensorineural hearing loss. C1 USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, Portsmouth, VA 23508 USA. RP McKinnon, BJ (reprint author), USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, Code 0609,630 John Paul Jones Circle, Portsmouth, VA 23508 USA. NR 9 TC 11 Z9 11 U1 0 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD NOV PY 1998 VL 163 IS 11 BP 792 EP 793 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 136HX UT WOS:000076854300015 PM 9819544 ER PT J AU Fliesler, SJ Lininger, LA Darrow, RM Organisciak, DT AF Fliesler, SJ Lininger, LA Darrow, RM Organisciak, DT TI Photoreceptor contribution to lipid mass and de novo synthesis in the rat retina. SO MOLECULAR BIOLOGY OF THE CELL LA English DT Meeting Abstract C1 St Louis Univ, Dept Ophthalmol, St Louis, MO 63104 USA. St Louis Univ, Program Mol & Cell Biol, St Louis, MO 63104 USA. USN, Drug Screening Lab, Great Lakes, IL USA. Wright State Univ, Dept Biochem & Mol Biol, Dayton, OH 45435 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CELL BIOLOGY PI BETHESDA PA PUBL OFFICE, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 1059-1524 J9 MOL BIOL CELL JI Mol. Biol. Cell PD NOV PY 1998 VL 9 SU S MA 2056 BP 354A EP 354A PG 1 WC Cell Biology SC Cell Biology GA 137GQ UT WOS:000076906702058 ER PT J AU Ngai, KL Moynihan, CT AF Ngai, KL Moynihan, CT TI The dynamics of mobile ions in ionically conducting glasses and other materials SO MRS BULLETIN LA English DT Article ID ALKALI OXIDE GLASSES; ELECTRICAL RELAXATION; AC-CONDUCTIVITY; DIELECTRIC-RELAXATION; FREQUENCY-DEPENDENCE; BETA-ALUMINA; TRANSPORT; MELTS; DIFFUSION; SPECTRA C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. Rensselaer Polytech Inst, Dept Mat Sci & Engn, Troy, NY 12180 USA. RP Ngai, KL (reprint author), USN, Res Lab, Div Elect Sci & Technol, 4555 Overlook Ave,Bldg 208,Room 224, Washington, DC 20375 USA. EM ngai@estd.nrl.navy.mil; moynic@rpi.edu NR 54 TC 90 Z9 90 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD NOV PY 1998 VL 23 IS 11 BP 51 EP 56 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 139GV UT WOS:000077020700017 ER PT J AU Hepburn, RD AF Hepburn, RD TI The development and decline in United States Navy ship repair capacity SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The culmination of recent public and private shipyard closures has significantly reduced the marine repair capacity of the United States. This paper discusses the historical legacy of the U.S. Navy ship construction and repair facilities in the United States from its earliest years to what is left today. It describes the evolution of the physical dry-docking facilities which includes marine railways, graving docks, floating dry-docks, floodable barges, and heavy-lift ships and their impact on U.S. Naval history. Specific technical aspects of the docking facilities are included ranging from construction to operational challenges. C1 USN, Sea Syst Command, Surface Ship Design & Syst Engn Grp, Arlington, VA 22217 USA. RP Hepburn, RD (reprint author), USN, Sea Syst Command, Surface Ship Design & Syst Engn Grp, Arlington, VA 22217 USA. NR 20 TC 0 Z9 0 U1 1 U2 2 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD NOV PY 1998 VL 110 IS 6 BP 25 EP 41 PG 17 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA 156BF UT WOS:000077981000005 ER PT J AU Cheng, LY Rao, NA Keefe, KS Avila, CP Macdonald, JC Freeman, WR AF Cheng, LY Rao, NA Keefe, KS Avila, CP Macdonald, JC Freeman, WR TI Cytomegalovirus iritis SO OPHTHALMIC SURGERY AND LASERS LA English DT Article ID IMMUNE-DEFICIENCY-SYNDROME; RETINITIS AB We describe a case of focal cytomegalovirus iritis in a patient with acquired imunodeficiency syndrome (AIDS) who had CMV retinitis. The autopsy showed histologic evidence of focal iritis in the left eye. This iritis was characterized by infiltration of acute inflammatory cells mixed with cytomegalic cells, which was confirmed by CMV-specific immunohistochemical staining. The case suggested that cytomegalovirus could be a direct causative agent of infectious iritis in RIDS patients. C1 Univ Calif San Diego, Dept Ophthalmol, Shiley Eye Ctr, La Jolla, CA 92093 USA. Univ So Calif, Sch Med, Doheny Eye Inst, Los Angeles, CA 90033 USA. USN, Med Ctr, Dept Ophthalmol, San Diego, CA 92152 USA. RP Freeman, WR (reprint author), Univ Calif San Diego, Dept Ophthalmol, Shiley Eye Ctr, 9415 Campus Point Dr, La Jolla, CA 92093 USA. FU NEI NIH HHS [EYO 7366] NR 6 TC 9 Z9 9 U1 0 U2 0 PU SLACK INC PI THOROFARE PA 6900 GROVE RD, THOROFARE, NJ 08086 USA SN 0022-023X J9 OPHTHALMIC SURG LAS JI Ophthalmic Surg. Lasers PD NOV PY 1998 VL 29 IS 11 BP 930 EP 932 PG 3 WC Ophthalmology; Surgery SC Ophthalmology; Surgery GA 138VF UT WOS:000076993500009 PM 9824866 ER PT J AU Choplin, NT Lundy, DC Dreher, AW AF Choplin, NT Lundy, DC Dreher, AW TI Differentiating patients with glaucoma from glaucoma suspects and normal subjects by nerve fiber layer assessment with scanning laser polarimetry SO OPHTHALMOLOGY LA English DT Article; Proceedings Paper CT Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY MAY 11-17, 1997 CL FT LAUDERDALE, FLORIDA SP Assoc Res Vis & Ophthalmol ID THICKNESS AB Purpose: A study was conducted to determine normative data for nerve fiber layer measurements as obtained by scanning laser polarimetry with the Laser Diagnostic Technologies Nerve Fiber Analyzer II, identify factors affecting the measurements, and identify parameters capable of differentiating normal subjects from patients with glaucoma and patients suspected of having glaucoma because of ocular hypertension or because of a large cup-to-disc ratio (GS-disc). Design: A case series. Participants: Four hundred normal subjects, 35 patients with ocular hypertension, 42 patients with glaucoma, and 17 glaucoma suspects based on optic disc appearance participated. Methods: Nerve fiber layer thickness assessments were determined in normal subjects (with normal-appearing optic nerves and normal visual fields). The results were compared to measurements from samples of age-matched patients with ocular hypertension (with normal visual fields), patients suspected of having glaucoma based on enlarged cup-to-disc ratios, and patients with open-angle glaucoma who had visual field loss. Results: The majority of the parameters derived from the measurements showed no significant relationship to age, although some parameters tended to decrease with increasing age. Multiple parameters showed statistically significant differences between normal subjects and patients with glaucoma. In particular, the intraellipse sector variability, an indirect measure of the shape of the nerve fiber layer in an ellipse surrounding the nerve head, showed statistically significant differences between normal subjects and patients with glaucoma as well as between glaucoma suspects and normal subjects. Similar results were seen with the superior maxima, the average thickness assessment value of the 1500 thickest points in the superior bundle. Conclusions: Assessments of nerve fiber layer thickness as determined by scanning laser polarimetry can differentiate patients with glaucoma from normal subjects and may identify otherwise undetected damage in glaucoma suspects. C1 USN, Med Ctr, Dept Clin Res, San Diego, CA 92134 USA. USN, Med Ctr, Dept Ophthalmol, San Diego, CA 92134 USA. Laser Diagnost Technol, San Diego, CA USA. RP Choplin, NT (reprint author), USN, Med Ctr, Dept Clin Res, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 5 TC 116 Z9 122 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0161-6420 J9 OPHTHALMOLOGY JI Ophthalmology PD NOV PY 1998 VL 105 IS 11 BP 2068 EP 2076 DI 10.1016/S0161-6420(98)91127-7 PG 9 WC Ophthalmology SC Ophthalmology GA 135YX UT WOS:000076831500027 PM 9818608 ER PT J AU Balough, BJ Hoffer, ME Wester, D O'Leary, MJ Brooker, CR Goto, M AF Balough, BJ Hoffer, ME Wester, D O'Leary, MJ Brooker, CR Goto, M TI Kinetics of gentamicin uptake in the inner ear of Chinchilla langier after middle-ear administration in a sustained-release vehicle SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT 100th Annual Meeting of the American-Academy-of-Otolaryngology-Head-and-Neck-Surgery CY SEP 29-OCT 02, 1996 CL WASHINGTON, D.C. SP Amer Acad Otolaryngol Head & Neck Surg AB The search for a safe, effective treatment for the vertigo associated with Meniere's disease has long been an important topic in otolaryngology. In recent years many groups have begun using intratympanic gentamicin to treat this vertigo. Although reported cure rates are as high as 90%, many questions remain regarding this type of treatment. Current limitations are the necessity for repeated treatments and a lack of clear dosing guidelines. In addition, the gentamicin must be delivered in a manner that allows maximal vestibulotoxic effect without injury to hearing. Until investigators can control the exact amount of medicine that is placed in the ear and have an understanding of the kinetics of gentamicin absorption, adequate dosing guidelines will be difficult to establish, and therapy will continue to rely on empiric data. We describe the use of a fibrin-based sustained-release vehicle, impregnated with gentamicin, injected into the middle ear of chinchillas. This allows for a prolonged effect without repeated dosing. Using this model, we studied the absorption kinetics of gentamicin at time points ranging from 8 hours to 1 week after injection. We used our findings to create a kinetics curve of gentamicin absorption. We discuss the shape and characteristics of this kinetics curve and examine the effects of the fibrin-based sustained-release vehicle and gentamicin on the middle ear. We noted no absorption in the contralateral (untreated ear) or blood. Through better understanding of the actions of gentamicin in this animal model, we hope to facilitate safer use of intratympanic medicines in our patient population and initiate programs for the use of this sustained-release vehicle in human beings. C1 USN, San Diego Med Ctr, Dept Otolaryngol, Dept Def,Spacial Orientat Ctr, San Diego, CA 92131 USA. RP Hoffer, ME (reprint author), USN, San Diego Med Ctr, Dept Otolaryngol, Dept Def,Spacial Orientat Ctr, San Diego, CA 92131 USA. NR 7 TC 38 Z9 41 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD NOV PY 1998 VL 119 IS 5 BP 427 EP 431 DI 10.1016/S0194-5998(98)70097-X PG 5 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA 137JR UT WOS:000076912000001 PM 9807064 ER PT J AU Harley, EH Dattolo, RA AF Harley, EH Dattolo, RA TI Ibuprofen for tonsillectomy pain in children: Efficacy and complications SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT Meeting of the American-Society-of-Pediatric-Otolaryngology CY MAY 07-13, 1994 CL PALM BEACH, FLORIDA SP Amer Soc Pediat Otolaryngol ID NONSTEROIDAL ANTIINFLAMMATORY DRUGS; KETOROLAC TROMETHAMINE; POSTOPERATIVE PAIN; MANAGEMENT; ADENOIDECTOMY; HEMORRHAGE AB We designed a prospective, randomized, double-blind study to test the efficacy and safety of ibuprofen compared with acetaminophen with codeine for pediatric posttonsillectomy/adenotonsillectomy patients. Twenty-seven children, aged 6 to 16 years, were enrolled. We collected information on pain control, return to normal sleep pattern, return to normal diet, and duration for which medication was required. Coagulation profiles were measured before surgery and on postoperative day 3, Acetaminophen with codeine was more effective in controlling pain on days 1 and 3 (p = 0.0475 and 0.0328, respectively). However, we detected no difference between the treatment groups (p = 0.2216) with regard to pain control on day 5, The ibuprofen group required medication for a longer period (p 0.0464). We detected no statistically significant differences between groups with regard to return to normal diet (p = 0.2346) and return to normal sleep pattern (p = 0.9554). The postoperative hemorrhage rate was 0% in the acetaminophen-with-codeine group and 12.5% in the ibuprofen group. The ibuprofen group demonstrated a mean increase in bleeding time of 2.07 minutes on the third postoperative day (p = 0.0379). The mean change in postoperative bleeding time between the two groups was statistically significant (p = 0.0140). We found no statistically significant differences in prothrombin time and partial thromboplastin time between groups. On the basis of the findings of this pilot study, we conclude that acetaminophen with codeine is safer and more efficacious than ibuprofen in the management of posttonsillectomy/adenotonsillectomy pain in children. C1 USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, San Diego, CA 92152 USA. RP Harley, EH (reprint author), Georgetown Univ, Med Ctr, Dept Otolaryngol Head & Neck Surg, 3800 Reservoir Rd NW, Washington, DC 20007 USA. NR 13 TC 54 Z9 55 U1 0 U2 2 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD NOV PY 1998 VL 119 IS 5 BP 492 EP 496 DI 10.1016/S0194-5998(98)70107-X PG 5 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA 137JR UT WOS:000076912000012 PM 9807075 ER PT J AU Bach, KK Malis, DJ Magit, AE Pransky, SM Kearns, DB Seid, AB AF Bach, KK Malis, DJ Magit, AE Pransky, SM Kearns, DB Seid, AB TI Acute coalescent mastoiditis in an infant: An emerging trend? SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, San Diego, CA 92134 USA. Childrens Hosp, Dept Pediat Otolaryngol, San Diego, CA USA. Univ Calif San Diego, Med Ctr, Div Otolaryngol, San Diego, CA 92103 USA. RP Bach, KK (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 7 TC 11 Z9 11 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD NOV PY 1998 VL 119 IS 5 BP 523 EP 525 DI 10.1016/S0194-5998(98)70117-2 PG 3 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA 137JR UT WOS:000076912000022 PM 9807085 ER PT J AU Kelso, JM AF Kelso, JM TI Latex allergy SO PEDIATRIC ANNALS LA English DT Article ID SENSITIZATION; PRODUCTS C1 USN, Med Ctr, Dept Clin Invest, Div Allergy, San Diego, CA 92134 USA. RP Kelso, JM (reprint author), USN, Med Ctr, Dept Clin Invest, Div Allergy, San Diego, CA 92134 USA. NR 10 TC 3 Z9 3 U1 0 U2 0 PU SLACK INC PI THOROFARE PA 6900 GROVE RD, THOROFARE, NJ 08086 USA SN 0090-4481 J9 PEDIATR ANN JI Pediatr. Annu. PD NOV PY 1998 VL 27 IS 11 BP 736 EP 739 PG 4 WC Pediatrics SC Pediatrics GA 138JK UT WOS:000076968600006 PM 9826879 ER PT J AU Hess, DW Deisz, JJ Serene, JW AF Hess, DW Deisz, JJ Serene, JW TI Single-particle excitations in a two-dimensional strong-coupling superconductor SO PHILOSOPHICAL MAGAZINE LETTERS LA English DT Article ID COHERENCE LENGTH SUPERCONDUCTORS; HUBBARD-MODEL; SUPERFLUID DENSITY; BOSE CONDENSATION; 2 DIMENSIONS; SYSTEMS; FLUCTUATIONS; TRANSITION; STATE AB We present calculations of the single-particle excitation spectrum for a two-dimensional strong-coupling superconductor in a conserving approximation. Spectral weight at low frequency is substantially reduced as the superconducting transition is approached from the normal stare. The suppression of low-energy excitations is a consequence of Cooper-pair fluctuations that are described self-consistently in the fluctuation exchange approximation. The static and uniform electromagnetic response provides a measure of the super fluid density and a fully self-consistent indication of the superconducting transition temperature. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Black Hills State Univ, Dept Phys Sci, Spearfish, SD 57799 USA. Georgetown Univ, Dept Phys, Washington, DC 20057 USA. RP Hess, DW (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. NR 29 TC 2 Z9 2 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0950-0839 J9 PHIL MAG LETT JI Philos. Mag. Lett. PD NOV PY 1998 VL 78 IS 5 BP 393 EP 402 DI 10.1080/095008398177797 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 136DR UT WOS:000076843700008 ER PT J AU Cross, JO Newville, M Rehr, JJ Sorensen, LB Bouldin, CE Watson, G Gouder, T Lander, GH Bell, MI AF Cross, JO Newville, M Rehr, JJ Sorensen, LB Bouldin, CE Watson, G Gouder, T Lander, GH Bell, MI TI Inclusion of local structure effects in theoretical x-ray resonant scattering amplitudes using ab initio x-ray-absorption spectra calculations SO PHYSICAL REVIEW B LA English DT Article ID ANOMALOUS FINE-STRUCTURE; SYNCHROTRON RADIATION; POLARIZED DISPERSION; PHASE DETERMINATION; DIFFRACTION; REFLECTION; UO2 AB Improved calculations of Bragg peak intensities near atomic resonance are obtained by including the effect of the local environment around the resonant atoms on the resonant scattering amplitudes Delta f=f'+if" Theoretical absorption cross sections calculated by the ab initio x-ray-absorption code FEFF are used to obtain the imaginary part f" by extension of the optical theorem to nonforward scattering under the dipole approximation. The real part f' is obtained by a limited range Kramers-Kronig transform of the difference between f" based on FEFF and existing theoretical calculations of f" based on an isolated-atom model. The atomic part of Delta f calculated by FEFF for the resonant atom embedded in the local potential is assumed to have spherical symmetry; however, no restriction is placed on the spectral features due to multiple scattering of the intermediate-state virtual photoelectron. Bragg peak intensities calculated in the kinematic approximation using the FEFF-based Delta f are compared to intensities calculated using the isolated-atom Delta f and to experimental data for Cu metal and YBa2Cu3O6.8 at the Cu K absorption edge,and for UO2 at the U M-IV absorption edge. [S0163-1829(98)06541-2]. C1 Naval Res Lab, Washington, DC 20375 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Washington, Seattle, WA 98195 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Maryland Baltimore Cty, Baltimore, MD 21250 USA. Commiss European Communities, Joint Res Ctr, Inst Transuranium Elements, D-76125 Karlsruhe, Germany. RP Cross, JO (reprint author), Naval Res Lab, Washington, DC 20375 USA. EM jox@pnc.aps.anl.gov NR 45 TC 85 Z9 85 U1 0 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1998 VL 58 IS 17 BP 11215 EP 11225 DI 10.1103/PhysRevB.58.11215 PG 11 WC Physics, Condensed Matter SC Physics GA 133ZD UT WOS:000076716700036 ER PT J AU Bartoli, FJ Lindle, JR Flom, SR Shashidhar, R Rubin, G Selinger, JV Ratna, BR AF Bartoli, FJ Lindle, JR Flom, SR Shashidhar, R Rubin, G Selinger, JV Ratna, BR TI Director orientation and optical stripe texture in electroclinic liquid crystals SO PHYSICAL REVIEW E LA English DT Article ID CELLS; FIELD AB We report the appearance of two types of optical stripes with different spatial wavelengths in electroclinic liquid crystals exhibiting a layer deformation. The periodicity of one set of stripes (longer wavelength) scales as twice the thickness of the cell, while the second (shorter wavelength) set of stripes has a periodicity that is independent of the thickness. Finally, detailed data on the spatially resolved optical studies of the stripe texture are presented which suggest the origin of the two types of stripe deformation and provide a possible explanation of their dependence on electric field. [S1063-651X(98)13211-7]. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Bartoli, FJ (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RI Lindle, James/A-9426-2009; Selinger, Jonathan/D-1445-2010 OI Selinger, Jonathan/0000-0002-4982-2457 NR 13 TC 10 Z9 10 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD NOV PY 1998 VL 58 IS 5 BP 5990 EP 5996 DI 10.1103/PhysRevE.58.5990 PN A PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 139VU UT WOS:000077052100097 ER PT J AU Chen, L Zonca, F Santoro, RA Hu, G AF Chen, L Zonca, F Santoro, RA Hu, G TI Nonlinear dynamics of Alfven eigenmodes in toroidal plasmas SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Letter ID SATURATION; SHEAR; INSTABILITY; TOKAMAKS AB Nonlinear saturation of toroidal Alfven eigenmodes (TAE) via mode-mode couplings is investigated both analytically and numerically. It is demonstrated that, as the TAE mode amplitude increases, the corresponding nonlinear ponderomotive force produces a fine-structure density modulation, which then causes enhanced energy dissipation in the short scales and leads eventually to the nonlinear saturation of TAE. C1 Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. EURATOM, ENEA Fus, I-00044 Frascati, Rome, Italy. USN, Res Lab, Washington, DC 20375 USA. RP Chen, L (reprint author), Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. RI chen, liu/I-2297-2013; Zonca, Fulvio/I-8236-2016 OI Zonca, Fulvio/0000-0002-9270-4704 NR 12 TC 15 Z9 15 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD NOV PY 1998 VL 40 IS 11 BP 1823 EP 1829 DI 10.1088/0741-3335/40/11/001 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 143QQ UT WOS:000077268100001 ER PT J AU Xapsos, MA Messenger, SR Walters, RJ Summers, GP Burke, EA AF Xapsos, MA Messenger, SR Walters, RJ Summers, GP Burke, EA TI Probability of large solar proton events and their effect on the efficiency of GaAs solar cells SO PROGRESS IN PHOTOVOLTAICS LA English DT Article ID DISPLACEMENT DAMAGE; RADIATION; FLUENCES; SPACE AB Using a recently, updated database that includes the last four complete solar cycles, the probability of occurrence of large solar proton events has been analyzed for time periods of rep to seven active solar, years using extreme value statistics, Then an approach is presented for evaluating solar cell efficiency degradation caused by the large event, These results enable spacecraft designers to evaluate precisely the risk of exposure of solar arrays to large solar proton events over the course of a mission, As am example, the efficiency degradation of n\p GaAs\Ge solar cells caused by an event dth a > 10-MeV fluence of 1 x 10(10) cm(-2) is shown, This is compared to the degradation resulting from all events in the last solar cycle, and to the electron environment in geostationary orbit over the same period of time. (C) 1998 John Wiley & Sons, Ltd. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Largo, MD 20774 USA. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. RP Xapsos, MA (reprint author), USN, Res Lab, Code 6615,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 18 TC 0 Z9 0 U1 1 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD NOV-DEC PY 1998 VL 6 IS 6 BP 399 EP 406 DI 10.1002/(SICI)1099-159X(199811/12)6:6<399::AID-PIP222>3.0.CO;2-D PG 8 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 162VU UT WOS:000078368300001 ER PT J AU Basu, S Weber, EJ Bullett, TW Keskinen, MJ MacKenzie, E Doherty, P Sheehan, R Kuenzler, H Ning, P Bongiolatti, J AF Basu, S Weber, EJ Bullett, TW Keskinen, MJ MacKenzie, E Doherty, P Sheehan, R Kuenzler, H Ning, P Bongiolatti, J TI Characteristics of plasma structuring in the cusp/cleft region at Svalbard SO RADIO SCIENCE LA English DT Article; Proceedings Paper CT HLPS/GAPS Peaceful Valley III Workshop CY JUN 15-17, 1997 CL LYONS, CO SP Natl Sci Fdn, CEDAR Program, Utah State Univ, Ctr Atmospher & Space Sci ID F-LAYER PATCHES; POLAR-CAP; PHASE FLUCTUATIONS; AURORAL OVAL; LOW-ALTITUDE; CUSP; IONOSPHERE; IRREGULARITIES; DYNAMICS; SCINTILLATION AB Satellite scintillation, all-sky optical imager, and digisonde observations were coordinated during a cusp campaign conducted at Ny Alesund, Svalbard (78.9 degrees N, 11.8 degrees E; 75.7 degrees N corrected geomagnetic latitude, over the period January 4-15, 1997. This paper is focused on a study of the distribution and dynamics of mesoscale (tens of kilometers to tens of meters) electron density irregularities in the dayside auroral region. This study has been performed at Ny Alesund, Svalbard, by measuring the effects of these irregularities on the amplitude scintillation of 250-MHz transmissions from a quasi-stationary polar satellite as well as the amplitude and phase scintillation of 1.6-GHz signals from Global Positioning System (GPS) satellites. These GPS scintillation measurements were augmented by the use of dual-frequency (1.2 and 1.6 GHz) GPS phase data acquired at the same station by the Jet Propulsion Laboratory for the International GPS Geodynamic Service (IGS). The continuous 250-MHz scintillation observations explored the daytime auroral ionosphere 2 degrees poleward of Ny Alesund and showed that the scintillation spectra are often broad, as may be expected for irregularities in a turbulent flow region. Such irregularity dynamics were detected poleward of the nominal cusp region over the interval of 0600-1500 magnetic local time. The period of observations included the magnetic storm of January 10-11, 1997, when GPS observations of the IGS detected polar cap patches with total electron contents of 3 x 10(16) m(-2) and large-scale (tens of kilometers) phase variations at the GPS frequency of 1.6 GHz that corresponded to temporal gradients of 2 x 10(16) m(-2) min(-1). However, amplitude scintillations at the GPS frequency of 1.6 GHz could not be detected in association with these large-scale phase variations, indicating that the irregularities with wavelengths less than the Fresnel dimension of 400 m were below the detectable limit. This is shown to be consistent in the context of enhanced ionospheric convection determined by digisonde and scintillation spectra. C1 USAF, Res Lab, AFRL, VSBI, Hanscom AFB, MA 01731 USA. Boston Coll, Inst Sci Res, Newton, MA 02159 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. KEO Consultants, Brookline, MA 02146 USA. RP USAF, Res Lab, AFRL, VSBI, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. EM santimay@aol.com; webere@plh.af.mil; bullett@plh.af.mil; keskinen@ppd.nrl.navy.mil NR 32 TC 51 Z9 51 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 EI 1944-799X J9 RADIO SCI JI Radio Sci. PD NOV-DEC PY 1998 VL 33 IS 6 BP 1885 EP 1899 DI 10.1029/98RS01597 PG 15 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 145HR UT WOS:000077365500031 ER PT J AU Bunce, JA Clough, MO AF Bunce, JA Clough, MO TI Multibeam seabed topographic classification - A user report - Mapping tool can also be used to classify seabeds, providing real-time classification system for broad range of hydrographic, environmental & military operations SO SEA TECHNOLOGY LA English DT Article C1 USN, Oceanog Off, Stennis Space Ctr, MS 39529 USA. RP Bunce, JA (reprint author), USN, Oceanog Off, Stennis Space Ctr, MS 39529 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 USA SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD NOV PY 1998 VL 39 IS 11 BP 33 EP 38 PG 6 WC Engineering, Ocean SC Engineering GA 142NM UT WOS:000077206600005 ER PT J AU Wolf, GW AF Wolf, GW TI US Navy sonobuoys - Key to antisubmarine warfare - "Underwater ears" aid in measurement, prediction; Passive & active acoustic search & localization of targets; Final active SO SEA TECHNOLOGY LA English DT Article C1 USN, Sonobuoy Program, Crane, IN USA. RP Wolf, GW (reprint author), USN, Sonobuoy Program, Crane, IN USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 USA SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD NOV PY 1998 VL 39 IS 11 BP 41 EP 44 PG 4 WC Engineering, Ocean SC Engineering GA 142NM UT WOS:000077206600006 ER PT J AU Xapsos, MA Summers, GP Burke, EA AF Xapsos, MA Summers, GP Burke, EA TI Extreme value analysis of solar energetic proton peak fluxes SO SOLAR PHYSICS LA English DT Article ID FLUENCE MODEL AB An extreme value analysis of > 10 MeV solar proton event peak fluxes during the period 1967-1994 is carried out. The largest annual peak fluxes that exceed a few hundred cm(-2) s(-1) sr(-1) are described by the type II extreme value distribution. One implication of this finding is that the extreme value distribution can be related to the initial distribution of large peak fluxes. Assuming that the number of events is a Poisson variable, the initial distribution is shown to be a power law with parameters that are directly related to the extreme value distribution parameters. The power law thus determined for the initial cumulative distribution has an index of -0.68, and agrees well with the data for peak fluxes above a few hundred cm(-2) s(-1) sr(-1). Implications for using extreme Value methods in conjunction with initial distributions that are represented by power laws are discussed. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Maryland Baltimore Cty, Baltimore, MD 21250 USA. RP Xapsos, MA (reprint author), USN, Res Lab, Code 6615, Washington, DC 20375 USA. NR 17 TC 10 Z9 12 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD NOV PY 1998 VL 183 IS 1 BP 157 EP 164 DI 10.1023/A:1005075421711 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 161GT UT WOS:000078281400011 ER PT J AU Baird, JK AF Baird, JK TI Primaquine as anti-relapse therapy for Plasmodium vivax SO TRANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE LA English DT Letter C1 USN, Inst Med Res, Rockville, MD 20852 USA. RP Baird, JK (reprint author), USN, Inst Med Res, 12300 Washington Ave, Rockville, MD 20852 USA. NR 6 TC 8 Z9 8 U1 0 U2 0 PU ROYAL SOC TROPICAL MEDICINE PI LONDON PA MANSON HOUSE 26 PORTLAND PLACE, LONDON, ENGLAND W1N 4EY SN 0035-9203 J9 T ROY SOC TROP MED H JI Trans. Roy. Soc. Trop. Med. Hyg. PD NOV-DEC PY 1998 VL 92 IS 6 BP 687 EP 687 DI 10.1016/S0035-9203(98)90814-8 PG 1 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA 153HT UT WOS:000077828000031 PM 10326124 ER PT J AU Green, MM Selinger, JV AF Green, MM Selinger, JV TI Cosmic chirality SO SCIENCE LA English DT Letter C1 Polytech Univ, Herman F Mark Polymer Res Inst, Brooklyn, NY 11201 USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Green, MM (reprint author), Polytech Univ, Herman F Mark Polymer Res Inst, 6 Metrotech Ctr, Brooklyn, NY 11201 USA. RI Selinger, Jonathan/D-1445-2010 OI Selinger, Jonathan/0000-0002-4982-2457 NR 3 TC 13 Z9 14 U1 0 U2 6 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD OCT 30 PY 1998 VL 282 IS 5390 BP 880 EP 881 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 134DH UT WOS:000076727300022 PM 9841434 ER PT J AU Marchand, AP Alihodzic, S Bott, SG Watson, WH Bodige, SG Gilardi, R AF Marchand, AP Alihodzic, S Bott, SG Watson, WH Bodige, SG Gilardi, R TI Generation and trapping of 7-norbornylidenecarbene and a heptacyclic analog of this alkylidenecarbene SO TETRAHEDRON LA English DT Article ID CYCLOPENTYNE; STEREOCHEMISTRY; CYCLOADDITION; CYCLOBUTYNE; CYCLOHEXYNE; CARBENES; LUMOMER; STATES AB Reaction of 7-(dibromomethylene) norbornane (2) wi th n-BuLi resulted in alpha-elimination of Br-2 with concomitant formation of 7-norbornylidenecarbene (4a). When this reaction was performed in the absence of an alkene trapping agent, the col-responding cumulated triene, 5, was produced (47% yield). When 4a was generated in the presence of norbomadiene, the corresponding [2 + 2] cycloadduct, 7, was formed in 82% yield. Alkylidenecarbene 4a thus generated in the presence of cis-2-butene resulted in stereospecific formation of the corresponding cis cycloadduct, 8 (74% yield), thereby suggesting that 4a functions as a singlet unsaturated cal bene in this reaction. Similar reactions of 7-(dibromomethylene)-HCTD (11) with n-BuLi performed (i) in the absence of added alkene and (ii) in the presence of cyclohexene resulted in the formation of cumulated triene 14 (69% yield) and [2 + 2] alkylidenecalbene-alkene cycloadduct 15 (51%, yield), respectively. We find no evidence for the formation of cycloalkynes (i.e., 4b or 13b) in any of the reactions reported herein. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ N Texas, Dept Chem, Denton, TX 76203 USA. Univ Houston, Dept Chem, Houston, TX 77204 USA. Texas Christian Univ, Dept Chem, Ft Worth, TX 76129 USA. USN, Res Lab, Washington, DC 20375 USA. RP Marchand, AP (reprint author), Univ N Texas, Dept Chem, Denton, TX 76203 USA. RI Bott, Simon/C-2226-2017 OI Bott, Simon/0000-0001-7204-4561 NR 39 TC 4 Z9 4 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4020 J9 TETRAHEDRON JI Tetrahedron PD OCT 29 PY 1998 VL 54 IS 44 BP 13427 EP 13434 DI 10.1016/S0040-4020(98)00824-2 PG 8 WC Chemistry, Organic SC Chemistry GA 128MR UT WOS:000076411000007 ER PT J AU Ranganathan, D Haridas, V Gilardi, R Karle, IL AF Ranganathan, D Haridas, V Gilardi, R Karle, IL TI Self-assembling aromatic-bridged serine-based cyclodepsipeptides (serinophanes): A demonstration of tubular structures formed through aromatic pi-pi interactions SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID PEPTIDE NANOTUBES AB A variety of 18-membered cyclodepsipeptides with alternating repeats of aromatic (phenyl or pyridyl) and Ser units in the ring have been synthesized and studied by X-ray crystallography for self-assembly patterns. Single-crystal structures of the macrocycles showed similar, relatively flat-ring structures. Those molecules containing one or two pyridine units showed self-assembly by stacking one over the other, thus creating tubular structures using aromatic pi-pi interactions between Ph/Pyr or Pyr/Pyr as the main organizing force. The cylindrical stacks are further stabilized by water molecules acting as bridges in intermolecular hydrogen bonding. In both the macrocycle 4b, a hybrid of benzene and pyridine units connected through ester and amide bonds, respectively, and the macrocycle 4d with two pyridine units, the molecules form parallel cylindrical stacks wherein the aromatic rings interdigitate from one column to a neighboring one with a similar to 3.5-Angstrom separation between the planes of the rings. Macrocycle 4a, with two phenyl rings, packs in a herringbone fashion and does not form any tubes. Macrocycle 4a does not exhibit any internal hydrogen bonds. Only 4d forms a tube with an inner space large enough to accommodate a water molecule. C1 Indian Inst Chem Technol, Discovery Lab, Hyderabad 500007, Andhra Pradesh, India. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Karle, IL (reprint author), Indian Inst Chem Technol, Discovery Lab, Hyderabad 500007, Andhra Pradesh, India. RI V, haridas/K-2992-2012 NR 19 TC 101 Z9 103 U1 1 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD OCT 28 PY 1998 VL 120 IS 42 BP 10793 EP 10800 DI 10.1021/ja982244d PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA 133NR UT WOS:000076693100001 ER PT J AU Pickett, WE Singh, DJ AF Pickett, WE Singh, DJ TI Comment on "Bloch electrons in a Jahn-Teller crystal and an orbital-density-wave state due to the Berry phase" SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Univ Calif Davis, Dept Phys, Livermore, CA 95616 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Pickett, WE (reprint author), Univ Calif Davis, Dept Phys, Livermore, CA 95616 USA. RI Singh, David/I-2416-2012 NR 6 TC 1 Z9 1 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 26 PY 1998 VL 81 IS 17 BP 3802 EP 3802 DI 10.1103/PhysRevLett.81.3802 PG 1 WC Physics, Multidisciplinary SC Physics GA 132DX UT WOS:000076616000064 ER PT J AU Ngai, KL AF Ngai, KL TI Relation between some secondary relaxations and the alpha relaxations in glass-forming materials according to the coupling model SO JOURNAL OF CHEMICAL PHYSICS LA English DT Review ID MOLECULAR-DYNAMICS SIMULATION; LIQUID-CRYSTALLINE POLYMERS; BAND DIELECTRIC-SPECTROSCOPY; NUCLEAR-MAGNETIC-RESONANCE; BULK AMORPHOUS POLYMERS; SHORT-TIME DYNAMICS; BETA-RELAXATION; VISCOELASTIC PROPERTIES; SUPERCOOLED LIQUIDS; POLY(CYCLOHEXYL METHACRYLATE) AB Some secondary or beta relaxations in glass-forming materials involve molecular motions that bear strong resemblance to the primitive ct relaxations of the coupling model, although the two are not identical. For these beta relaxations, at the glass transition temperature T-g the relaxation time tau(beta)(T-g) is expected to be shorter than but not too different in order of magnitude from tau(0)(T-g), the primitive alpha-relaxation time at T-g. The latter can be calculated by the coupling model from the relaxation time tau(alpha)(T-g), the exponent (1-n) of the Kohlrausch-Williams-Watts (KWW) correlation function exp[-(t/tau(alpha))(1-n)], and the experimental crossover time, t(c)approximate to 2ps, of the alpha relaxation. From experimental data of beta and a relaxations in a variety of glass-forming materials, it is found that tau(beta)(T-g) and tau(o)(T-g) are close to each other in order of magnitude as anticipated. The results indicate these beta relaxations indeed bear some close relation to the corresponding primitive alpha relaxation, although they are not the same process. Since the relaxation times of the majority of these beta relaxations have the Arrhenius temperature dependence, tau(beta)(T) = tau(beta proportional to) exp(E-beta/RT), where tau(beta proportional to) is of the order of 10(-13)-10(-16) s, knowing, approximately, the value of tau(beta)(T) at one temperature T-g means the location of the beta relaxation in the relaxation map can be roughly determined from the alpha relaxation. The findings can be restated as the empirical result: there exists a strong correlation between the value of log[tau(beta)(T-g)] and the KWW exponent (1-n) of the alpha relaxation in many glass-formers. A smaller KWW exponent of the alpha relaxation corresponds to shorter tau(beta)(T-g) or smaller log[tau(beta)(T-g)]. This remarkable cross correlation between the ct relaxation and the beta relaxation should be of interest for any model or theory of molecular dynamics of glass formers. (C) 1998 American Institute of Physics. [S0021-9606(98)50140-7]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ngai, KL (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM ngai@estd.nrl.navy.mil NR 116 TC 269 Z9 270 U1 5 U2 39 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 22 PY 1998 VL 109 IS 16 BP 6982 EP 6994 DI 10.1063/1.477334 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 131ZV UT WOS:000076605900053 ER PT J AU Bloomer, JD Watson, DM Pipher, JL Forrest, WJ Ali, B Greenhouse, MA Satyapal, S Smith, HA Fischer, J AF Bloomer, JD Watson, DM Pipher, JL Forrest, WJ Ali, B Greenhouse, MA Satyapal, S Smith, HA Fischer, J TI A near-infrared study of NGC 7538 IRS 1, 2, and 3 SO ASTROPHYSICAL JOURNAL LA English DT Article DE H II regions; infrared : ISM : lines and bands; infrared : stars; ISM : individual (NGC 7538); open clusters and associations : individual (NGC 7538); stars : formation ID FE-II EMISSION; MOLECULAR CLOUDS; SUPERNOVA-REMNANTS; STAR-FORMATION; H-2 EMISSION; ORION NEBULA; WEAK LINES; REGIONS; INTERSTELLAR; NGC-7538 AB We present images of the cluster of embedded young stars designated NGC 7538 IRS 1, 2, and 3 in the J (1.25 mu m), H (1.64 mu m), and K (2.16 mu m) broad bands; the 1.64 mu m line of [Fe II]; the 2.12 mu m and 2.25 mu m lines of H-2; the 2.17 mu m Brackett gamma H-recombination line; and the 3.29 mu m "unidentifed" dust feature. The NGC 7538 IRS 2 compact H II region, as seen in Brackett gamma line emission, possesses a cometary morphology. We find evidence for a shell-like distribution of [Fe II] line emission along the periphery of the compact H II region. This morphology and the observed intensity ratio [Fe II] 1.64 mu m)I(Br gamma) imply that the [Fe II] line emission emanates from shocked stellar wind material. We observe arcs of H, line emission immediately exterior to the [Fe II] line emission shell and suggest that these arcs delineate molecular cloud material shocked via collision with the stellar wind. We observe larger area with centers of curvature displaced from each other and IRS 2, in broad-band-continuum, H-2-line, and 3.29 mu m feature emission, and suggest that these arcs represent molecular gas (either shocked or UV-excited) and dust swept up during distinct episodes of stellar mass ejection. We submit that the morphological and energetic evidence favors a "stellar wind bow shock" interpretation, in which the motion of the central O star with respect to the surrounding molecular cloud, in conjunction with the star's high-velocity stellar wind and episodic mass ejection, gives rise to the observed general cometary morphology and circum-H II region emission. C1 Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. RP Bloomer, JD (reprint author), Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. NR 57 TC 20 Z9 20 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 20 PY 1998 VL 506 IS 2 BP 727 EP 742 DI 10.1086/306268 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LM UT WOS:000077779100022 ER PT J AU Montes, MJ Van Dyk, SD Weiler, KW Sramek, RA AF Montes, MJ Van Dyk, SD Weiler, KW Sramek, RA TI Radio observations of SN 1980K: Evidence for rapid presupernova evolution SO ASTROPHYSICAL JOURNAL LA English DT Article DE radio continuum : stars; stars : evolution; supernovae : individual (SN 1980K) ID LARGE ARRAY; OPTICAL-EMISSION; SUPERNOVAE; REMNANTS; M83 AB New observations of the supernova SN 1980K made with the VLA at 20 cm and 6 cm from 1994 April through 1996 October show that it has undergone a significant change in its radio emission evolution, dropping by a factor of similar to 2 below the flux density S proportional to t(-0.73) power-law decline with time t observed earlier. However, although S at all observed frequencies has decreased significantly, its current spectral index of alpha = -0.42 +/- 0.15 (S proportional to v(+alpha)) is consistent with the previous spectral index of alpha = -0.60(-0.07)(+0.04). It is suggested that this decrease in emission may be due to the supernova (SN) shock entering a new region of the circumstellar material that has a lower density than that expected for a constant speed (w), constant mass-loss rate ((M) over dot) wind from the progenitor. If such an interpretation is correct, the difference in wind and shock speeds appears to indicate a significant evolution in the mass-loss history of the SN progenitor similar to 10(4) yr before explosion, with a change in circumstellar density (proportional to (M) over dot/w) occurring over a time span of less than or similar to 4 kyr. Such features could be explained in terms of a fast "blue-loop" evolutionary phase of a relatively massive pre-SN progenitor star. If so, we may, for the first time, provide a stringent constraint on the mass of the SN progenitor based solely on the SN's radio emission. C1 USN, Res Lab, Washington, DC 20375 USA. CALTECH, IPAC, Pasadena, CA 91125 USA. USN, Res Lab, Washington, DC 20375 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Montes, MJ (reprint author), USN, Res Lab, Code 7214, Washington, DC 20375 USA. RI Montes, Marcos/J-9239-2015 OI Montes, Marcos/0000-0002-4725-5380 NR 26 TC 51 Z9 51 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 20 PY 1998 VL 506 IS 2 BP 874 EP 879 DI 10.1086/306261 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LM UT WOS:000077779100034 ER PT J AU Stone, RC AF Stone, RC TI New observations testing the adopted Hipparcos link to the International Celestial Reference Frame SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrometry; reference systems ID EXTRAGALACTIC REFERENCE FRAME; CATALOG; FK5 AB This paper tests the Hipparcos link to the extragalactic reference frame by using new data obtained after the release of the catalog, thereby providing an external check on the accuracy of the established link process. The new data consist of 689 positions of Hipparcos stars determined in the International Celestial Reference Frame (ICRF) from CCD observations taken with the Flagstaff Astrometric Scanning Transit Telescope (FASTT). A comparison of the FASTT and Hipparcos catalog star positions observed in common finds that the axial rotations between the Hipparcos and ICRF reference frames are, respectively, (epsilon(x), epsilon(y), epsilon(z)) = (-2.2 +/- 3.3, -2.2 +/- 3.3, 3.3 +/- 2.9) (s.e.) mas at epoch 1996.5. All of these rotations are small and insignificant with respect to their errors (epsilon(x) and epsilon(y) are less than 1 sigma detections whereas epsilon(z) is only a 1.1 sigma detection). Hence, this paper finds that the Hipparcos link to the ICRF was well determined and is not seriously degrading with time. C1 USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. RP Stone, RC (reprint author), USN Observ, Flagstaff Stn, POB 1149, Flagstaff, AZ 86002 USA. EM rcs@nofs.navy.mil NR 15 TC 5 Z9 5 U1 0 U2 0 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 OCT 20 PY 1998 VL 506 IS 2 BP L93 EP L96 DI 10.1086/311654 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LP UT WOS:000077779300004 ER PT J AU Stenger-Smith, JD Zarras, P Merwin, LH Shaheen, SE Kippelen, B Peyghambarian, N AF Stenger-Smith, JD Zarras, P Merwin, LH Shaheen, SE Kippelen, B Peyghambarian, N TI Synthesis and characterization of poly(2,5-bis(N-methyl-N-hexylamino)phenylene vinylene), a conjugated polymer for light-emitting diodes SO MACROMOLECULES LA English DT Article ID SPECTROSCOPY C1 USN, Air Warfare Ctr, Chem & Mat Branch, China Lake, CA 93555 USA. RP Stenger-Smith, JD (reprint author), USN, Air Warfare Ctr, Chem & Mat Branch, China Lake, CA 93555 USA. RI Kippelen, Bernard/I-4058-2013; Shaheen, Sean/M-7893-2013 OI Kippelen, Bernard/0000-0002-8417-7051; NR 17 TC 22 Z9 22 U1 2 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 20 PY 1998 VL 31 IS 21 BP 7566 EP 7569 DI 10.1021/ma980865l PG 4 WC Polymer Science SC Polymer Science GA 131LY UT WOS:000076578600061 ER PT J AU Krowne, CM AF Krowne, CM TI Symmetry considerations applied to 3-D dyadic Green's functions for three-port inhomogeneous microstrip ferrite circulator SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE inhomogeneous ferrite; dyadic Green's function; symmetry; microstrip circulator; three-port AB Compacted perimeter 3-D dyadic Green's functions are derived under threefold symmetry for a circular ferrite circulator which is radially inhomogenous. It is demonstrated how the perpendicular electric field, and therefore the s-parameters, may be determined with these dyadic Green's functions. A large reduction in the number of dyadic Green's function elements required for numerical evaluation results, simplifying all formulas dependent upon these elements. (C) 1998 John Wiley & Sons, Inc. C1 USN, Res Lab, Electron Sci & Technol Div, Microwave Technol Branch, Washington, DC 20375 USA. RP Krowne, CM (reprint author), USN, Res Lab, Electron Sci & Technol Div, Microwave Technol Branch, Code 6850-3, Washington, DC 20375 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0895-2477 J9 MICROW OPT TECHN LET JI Microw. Opt. Technol. Lett. PD OCT 20 PY 1998 VL 19 IS 3 BP 227 EP 229 PG 3 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA 124EG UT WOS:000076168000016 ER PT J AU Wang, RB Doolan, DL Le, TP Hedstrom, RC Coonan, KM Charoenvit, YP Jones, TR Hobart, P Margalit, M Ng, J Weiss, WR Sedegah, M de Taisne, C Norman, JA Hoffman, SL AF Wang, RB Doolan, DL Le, TP Hedstrom, RC Coonan, KM Charoenvit, YP Jones, TR Hobart, P Margalit, M Ng, J Weiss, WR Sedegah, M de Taisne, C Norman, JA Hoffman, SL TI Induction of antigen-specific cytotoxic T lymphocytes in humans by a malaria DNA vaccine SO SCIENCE LA English DT Article ID FALCIPARUM CIRCUMSPOROZOITE PROTEIN; PLASMODIUM-FALCIPARUM; RHESUS-MONKEYS; CELL EPITOPES; PROTECTION; IMMUNIZATION; CHIMPANZEES; CANDIDATE; RESPONSES; IMMUNITY AB CD8(+) cytotoxic T lymphocytes (CTLs) are critical for protection against intracellular pathogens but often have been difficult to induce by subunit vaccines in animals. DNA vaccines elicit protective CD8(+) T cell responses. Malaria-naive volunteers who were vaccinated with plasmid DNA encoding a malaria protein developed antigen-specific, genetically restricted, CD8(+) T cell-dependent CTLs. Responses were directed against all 10 peptides tested and were restricted by six human lymphocyte antigen (HLA) class I alleles. This first demonstration in healthy naive humans of the induction of CD8(+) CTLs by DNA vaccines, including CTLs that were restricted by multiple HLA alleles in the same individual, provides a foundation for further human testing of this potentially revolutionary vaccine technology. C1 USN, Med Res Inst, Malaria Program, Bethesda, MD 20889 USA. Henry M Jackson Fdn, Rockville, MD 20852 USA. WHO, Reg Off, Pan Amer Hlth Org, Washington, DC 20037 USA. USA, Med Res Inst Infect Dis, Div Med, Ft Detrick, MD 21701 USA. Vical, San Diego, CA 92121 USA. USN, Med Res Inst, US Dept Def, Bone Marrow Donor Program, Bethesda, MD 20889 USA. Pasteur Merieux Connaught France, F-69007 Lyon, France. RP Hoffman, SL (reprint author), USN, Med Res Inst, Malaria Program, Bethesda, MD 20889 USA. RI Doolan, Denise/F-1969-2015 NR 32 TC 604 Z9 630 U1 3 U2 19 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD OCT 16 PY 1998 VL 282 IS 5388 BP 476 EP 480 DI 10.1126/science.282.5388.476 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 129TT UT WOS:000076479600055 PM 9774275 ER PT J AU Blivin, SJ Raspa, RF AF Blivin, SJ Raspa, RF TI Diagnosis of acromioclavicular joint dislocations SO AMERICAN FAMILY PHYSICIAN LA English DT Letter C1 Naval Hosp, Jacksonville, FL 32214 USA. RP Blivin, SJ (reprint author), Naval Hosp, 2080 Child St, Jacksonville, FL 32214 USA. NR 7 TC 0 Z9 0 U1 1 U2 1 PU AMER ACAD FAMILY PHYSICIANS PI KANSAS CITY PA 8880 WARD PARKWAY, KANSAS CITY, MO 64114-2797 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD OCT 15 PY 1998 VL 58 IS 6 BP 1298 EP + PG 2 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 131LE UT WOS:000076576900005 PM 9803189 ER PT J AU Rabbany, SY Marganski, WA Kusterbeck, AW Ligler, FS AF Rabbany, SY Marganski, WA Kusterbeck, AW Ligler, FS TI A membrane-based displacement flow immunoassay SO BIOSENSORS & BIOELECTRONICS LA English DT Article DE explosives detection; displacement immunoassay; membrane; biosensor; immobilized IgG ID IMMUNOSENSOR; KINETICS; EXPLOSIVES; BINDING; ASSAY; WATER AB The use of a membrane-based continuous Bow displacement immunoassay for detection of nanomolar quantities of explosives is demonstrated, and the kinetics of this system are characterized through experimentation. Antibodies of 2,4,6-trinitrotoluene (TNT) are immobilized onto a porous membrane with surface reactive sites designed to facilitate the covalent binding of the antibody. After saturating the immobilized antibody binding sites with labeled antigen, target analyte is introduced in Bow, and the displacement reactions are monitored using a fluorometer. The displaced labeled antigen detected is proportional to the concentration of the analyte introduced to the antibody-labeled antigen complex. Multiple assays were performed at Bow rates of 2.0, 1.0, 0.50, and 0.25 mL/min using membranes saturated with varying TNT antibody concentrations. The signal intensity (i.e. the concentration of displaced labeled antigen) was independent of antibody concentration at 1.0 mL/min, but proportional to antibody concentration at 0.25 mL/min. Our data suggests that the lower flow rate created a longer interaction time between the injected analyte and the antibody-labeled antigen complex, resulting in greater displacement of the labeled antigen and higher signal intensities than seen at higher flow rates. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Hofstra Univ, Bioengn Program, Hempstead, NY 11549 USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Rabbany, SY (reprint author), Hofstra Univ, Bioengn Program, 104 Weed Hall, Hempstead, NY 11549 USA. NR 19 TC 27 Z9 27 U1 0 U2 3 PU ELSEVIER ADVANCED TECHNOLOGY PI OXFORD PA OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0956-5663 J9 BIOSENS BIOELECTRON JI Biosens. Bioelectron. PD OCT 15 PY 1998 VL 13 IS 9 BP 939 EP 944 DI 10.1016/S0956-5663(98)00031-1 PG 6 WC Biophysics; Biotechnology & Applied Microbiology; Chemistry, Analytical; Electrochemistry; Nanoscience & Nanotechnology SC Biophysics; Biotechnology & Applied Microbiology; Chemistry; Electrochemistry; Science & Technology - Other Topics GA 136FX UT WOS:000076848800002 PM 9839382 ER PT J AU Pancrazio, JJ Bey, PP Loloee, A Manne, SR Chao, HC Howard, LL Gosney, WM Borkholder, DA Kovacs, GTA Manos, P Cuttino, DS Stenger, DA AF Pancrazio, JJ Bey, PP Loloee, A Manne, SR Chao, HC Howard, LL Gosney, WM Borkholder, DA Kovacs, GTA Manos, P Cuttino, DS Stenger, DA TI Description and demonstration of a CMOS amplifier-based-system with measurement and stimulation capability for bioelectrical signal transduction SO BIOSENSORS & BIOELECTRONICS LA English DT Article DE amplifier; cardiac myocytes; CMOS; extracellular recording; spinal cord neurons ID MICROELECTRODE ARRAY; NEURONAL NETWORKS; EVOKED-POTENTIALS; CULTURED NEURONS; ELECTRODES; CELLS; JUNCTION; SURFACE; CORTEX AB An extracellular recording system incorporating an electrode array and an amplifier/stimulator CMOS chip is described and characterized. Important features of this custom VLSI chip include 16 instrumentation amplifiers with a gain of 50 and the incorporation of a cross-point array allowing designation of an extracellular microelectrode as either a stimulator or sensor. The planar array consisted of 32 microelectrodes, 14 mu m in diameter, and four larger reference electrodes. Microelectrodes, interconnecting traces, and bond pads were patterned with a 500-nm layer of gold. The interconnecting traces were passivated with a 1-mu m thick layer of silicon nitride to provide chemical and electrical insulation and microelectrode impedance was lowered utilizing electrode position of platinum black. The amplifier exhibited a nearly flat frequency response with high pass and low pass corner frequencies of 0.7 Hz and 50 kHz, respectively. The input referred noise over the 50 kHz bandwidth was 12-16 mu V-RMS, well below the magnitude of previously reported extracellular potentials. Crosstalk between neighboring channels resulted in an output signal below the amplifier noise level, even for relatively large extracellular potentials. Using this system, extracellular recordings were demonstrated yielding typical peak-to-peak biopotentials of magnitude 0.9-2.1 mV and 100-400 mu V for chick cardiac myocytes and rat spinal cord neurons, respectively. The key components of this extracellular recording system can be manufactured using industry standard thin him photolithographic techniques. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. So Methodist Univ, Dept Elect Engn, Dallas, TX 75275 USA. Stanford Univ, Dept Elect Engn, Stanford, CA 94305 USA. Sci Applicat Int Corp, Rockville, MD 20850 USA. Geocenters Inc, Ft Washington, MD 20744 USA. RP Stenger, DA (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Code 6900, Washington, DC 20375 USA. EM howard@seas.smu.edu; dstenger@cbmse.nrl.navy.mil RI Bueno, Ligia/P-1359-2014; Pancrazio, Joseph/M-3206-2015 OI Pancrazio, Joseph/0000-0001-8276-3690 NR 29 TC 48 Z9 49 U1 0 U2 3 PU ELSEVIER ADVANCED TECHNOLOGY PI OXFORD PA OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0956-5663 J9 BIOSENS BIOELECTRON JI Biosens. Bioelectron. PD OCT 15 PY 1998 VL 13 IS 9 BP 971 EP 979 DI 10.1016/S0956-5663(98)00006-2 PG 9 WC Biophysics; Biotechnology & Applied Microbiology; Chemistry, Analytical; Electrochemistry; Nanoscience & Nanotechnology SC Biophysics; Biotechnology & Applied Microbiology; Chemistry; Electrochemistry; Science & Technology - Other Topics GA 136FX UT WOS:000076848800006 PM 9839386 ER PT J AU Goldberg, L Koplow, J AF Goldberg, L Koplow, J TI Compact, side-pumped 25dBm Er/Yb co-doped double cladding fibre amplifier SO ELECTRONICS LETTERS LA English DT Article ID DIODE; LASER AB A compact 1.5 mu m Er/Yb-doped double cladding fibre amplifier, diode side-pumped through an embedded v-groove, is demonstrated. A small signal gain of 47dB, an output power of 312mW and, separately, a noise figure of 4.5dB are measured. C1 USN, Res Lab, Washington, DC 20375 USA. RP Goldberg, L (reprint author), USN, Res Lab, Code 5670, Washington, DC 20375 USA. NR 7 TC 23 Z9 24 U1 1 U2 3 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD OCT 15 PY 1998 VL 34 IS 21 BP 2027 EP 2028 DI 10.1049/el:19981402 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 136EF UT WOS:000076845000027 ER PT J AU Eremeeva, ME Ching, WM Wu, YL Silverman, DJ Dasch, GA AF Eremeeva, ME Ching, WM Wu, YL Silverman, DJ Dasch, GA TI Western blotting analysis of heat shock proteins of Rickettsiales and other eubacteria SO FEMS MICROBIOLOGY LETTERS LA English DT Article DE heat shock protein; Rickettsia; Bartonella; Ehrlichia; Orientia; Wolbachia; Legionella; Proteus; eubacteria ID ESCHERICHIA-COLI; SPOTTED-FEVER; OPERON; TSUTSUGAMUSHI; SEQUENCES; HSP60; HSP70; DNAK; GRPE; GENE AB Heat shock proteins (Hsp) of four Rickettsia species, three Bartonella species, two Ehrlichia species, Orientia tsutsugamushi and seventeen other eubacterial species were characterized by the enhanced chemiluminescence Western blotting (WB) technique with antibodies raised against recombinant Hsp from Escherichia coli and purified GroES from R. typhi. Although E. coli DnaK and GroEL have epitopes that are highly conserved among the homologous proteins found in Rickettsia, Ehrlichia, O. tsutsugamushi, Bartonella and other Proteobacteria, anti-E. coli DnaK and GroEL monoclonal antibodies (Dasch et al. (1990) Ann. N.Y. Acad. Sci. 590, 352-369) recognize less conserved epitopes. In contrast, epitopes on E. coli DnaJ, GrpE and GroES are much less conserved since anti-E. coli DnaJ, GrpE and GroES polyclonal antibodies did not recognize DnaJ, GrpE or GroES homologues in Rickettsia, Bartonella, Orientia, Ehrlichia and Legionella. Polyclonal antiserum prepared against GroES from R. typhi reacted strongly with purified 10 kDa GroES peptide from Rickettsia and Bartonella, and strongly bound to proteins of varying electrophoretic mobility from Wolbachia, Legionella, Proteus and Shigella flexneri and more weakly to other GroES homologues including that found in E. coli. Consequently, commercially available anti-DnaJ, anti-GrpE and anti-GroES polyclonal antibodies and anti-DnaK monoclonal antibody raised against their respective recombinant E. coli Hsp are not, suitable for detection and identification of homologues of these proteins in a wide range of eubacteria. (C) 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved. C1 Univ Maryland, Sch Med, Dept Microbiol & Immunol, Baltimore, MD 21201 USA. USN, Med Res Inst, Bethesda, MD USA. RP Eremeeva, ME (reprint author), Univ Maryland, Sch Med, Dept Microbiol & Immunol, Baltimore, MD 21201 USA. EM meremeev@umaryland.edu FU NIAID NIH HHS [AI-17416] NR 26 TC 10 Z9 10 U1 0 U2 2 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0378-1097 EI 1574-6968 J9 FEMS MICROBIOL LETT JI FEMS Microbiol. Lett. PD OCT 15 PY 1998 VL 167 IS 2 BP 229 EP 237 DI 10.1016/S0378-1097(98)00394-2 PG 9 WC Microbiology SC Microbiology GA 132BY UT WOS:000076611100019 PM 9809424 ER PT J AU Batteen, ML Huang, MJ AF Batteen, ML Huang, MJ TI Effect of salinity on density in the Leewin Current System SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID CALIFORNIA CURRENT SYSTEM; LEEUWIN CURRENT; WESTERN-AUSTRALIA; OCEAN CIRCULATION; EDDIES; MODELS; HEAT AB Climatological temperature and salinity fields are used to calculate the salinity contribution to density and dynamic height fields in the Leeuwin Current System (LCS). While the temperature gradient is primarily linear, with warmest water to the north, the salinity fields are spatially inhomogeneous. A comparison of density fields, calculated with constant and variable salinity, shows that, off Western Australia, the density field is primarily determined by temperature. Off southwestern Australia, the density field is dependent on warm and salty (subtropical) and fresh and cold (sub-Antarctic) water masses. While the dynamic height fields, calculated with constant and variable salinity, show similar flow patterns off Western Australia, different flow patterns are found off southwestern Australia. In addition to the analysis of climatological fields, a primitive equation ocean model is used in a process-oriented study to investigate the role of salinity in the formation of currents and eddies in the LCS. Two identical ocean models, one with a climatological salinity field and the other with no horizontal salinity gradients, are run and compared with each other. Despite the model runs being initialized with similar temperature distributions, there are relatively large temperature and density differences in the southwestern Australian region due to the advection of water masses by the Leeuwin Current. On the basis of the climatological analyses and the results of the model experiments, it is concluded that, descriptively and dynamically, both temperature and salinity are essential to accurately characterize the large-scale circulation of the LCS. C1 USN, Dept Oceanog, Postgrad Sch, Monterey, CA 93943 USA. RP USN, Dept Oceanog, Postgrad Sch, Code OC-BV, Monterey, CA 93943 USA. EM batteen@oc.nps.navy.mil NR 31 TC 7 Z9 7 U1 0 U2 1 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 OCT 15 PY 1998 VL 103 IS C11 BP 24693 EP 24721 DI 10.1029/98JC01373 PG 29 WC Oceanography SC Oceanography GA 127XB UT WOS:000076374900009 ER PT J AU Spiel, DE AF Spiel, DE TI On the births of film drops from bubbles bursting on seawater surfaces SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID AIR BUBBLES; WATER; SEA AB The parameters describing the birth of him droplets originating from bubbles bursting on seawater surfaces are presented. Results are given for bubble sizes D-b from 2 to 14.6 mm equivalent volume diameter. It is shown, contrary to earlier reports, that the films of all bubbles with D-b up to at least 14.6 mm burst in an orderly manner in which a hole appears at a well-defined location, usually the film's edge, and propagates from there gathering up the film's mass into a toroidal ring as it progresses. This process is enabled because surface tension provides the force required to sustain the centripetal accelerations. Film drops are created when beads, of sufficient size, form along the length of the toroidal ring and surface tension is insufficient to maintain the centripetal accelerations at these accumulation points. Pieces of the ring break loose and leave the toroidal ring along paths tangential to the bubble's cap. It is shown that only bubbles larger than 2.4 mm diameter can launch film droplets by this means and that this begins when the film has rolled up through an angle of about 31 degrees independent of bath bubble size and (theoretically) surface tension. Film drop spray patterns recorded on MgO-coated cylindrical shells surrounding the burst bubbles yield film drop numbers and trajectories. In addition, film drop size distributions, their speed of launch, and the speed at which the film opens have been determined as a function of bubble size. The droplet sizes cited here are substantially larger than most previous estimates, and with a high probability, these droplets follow downward trajectories which lead them to impact the surface. A strong inference may be drawn that these impacts give birth to secondary droplets that are smaller than their parents and which have upward velocity components. C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. RP Spiel, DE (reprint author), USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. NR 19 TC 62 Z9 67 U1 0 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD OCT 15 PY 1998 VL 103 IS C11 BP 24907 EP 24918 DI 10.1029/98JC02233 PG 12 WC Oceanography SC Oceanography GA 127XB UT WOS:000076374900021 ER PT J AU Gu, W Xu, Q Wu, RS AF Gu, W Xu, Q Wu, RS TI Three-dimensional instability of nonlinear viscous symmetric circulations SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID SEVERE FRONTAL RAINBAND; MID-LATITUDE CYCLONES; INERTIAL INSTABILITY; MICROSCALE STRUCTURE; STABILITY; MESOSCALE; CLOUDS; PRECIPITATION; ORGANIZATION; ENERGETICS AB A spectral model is developed to study the three-dimensional instability of nonlinear viscous symmetric circulations. Two-dimensional solutions of steady nonlinear viscous symmetric circulations are found to be unstable in three dimensions. Four types of unstable modes are identified. The type I mode is characterized by horizontally tilted bands, similar to the tilted primary mode obtained previously by other investigators. This mode may be viewed as a gradual emergence of the tilted primary mode in three dimensions: The remaining three modes are highly three-dimensional and emerge consecutively as the basic-state Richardson number decreases significantly below the critical value. Implications of these modes to the possible secondary instabilities of tilted primary nonlinear circulations are discussed. C1 USN, Res Lab, Monterey, CA 93943 USA. Univ Oklahoma, CIMMS, Norman, OK 73019 USA. Nanjing Univ, Dept Atmospher Sci, Nanjing 210008, Peoples R China. RP Xu, Q (reprint author), USN, Res Lab, 7 Grace Hopper Dr, Monterey, CA 93943 USA. NR 31 TC 9 Z9 11 U1 2 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD OCT 15 PY 1998 VL 55 IS 20 BP 3148 EP 3158 DI 10.1175/1520-0469(1998)055<3148:TDIONV>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 132CC UT WOS:000076611500004 ER PT J AU Gu, XH Korotkov, RY Ding, YJ Kang, JU Khurgin, JB AF Gu, XH Korotkov, RY Ding, YJ Kang, JU Khurgin, JB TI Observation of backward sum-frequency generation in periodically-poled lithium niobate SO OPTICS COMMUNICATIONS LA English DT Article ID 2ND-HARMONIC GENERATION; BLUE-LIGHT; WAVE; LINBO3; RED AB We report experimental observation of backward sum-frequency generation in periodically-poled LiNbO3 resulting from mixing between the forward propagating fundamental beam with the second harmonic beam. Although the forward second harmonic beam itself is not phase-matched, the sum-frequency generation exhibits several phase-matching peaks. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Bowling Green State Univ, Dept Phys & Astron, Ctr Mat & Photochem Sci, Bowling Green, OH 43403 USA. USN, Res Lab, Washington, DC 20375 USA. Johns Hopkins Univ, Dept Elect & Comp Engn, Baltimore, MD 21218 USA. RP Ding, YJ (reprint author), Bowling Green State Univ, Dept Phys & Astron, Ctr Mat & Photochem Sci, Bowling Green, OH 43403 USA. RI Kang, Jin/A-3228-2010; khurgin, Jacob/A-3278-2010 NR 18 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD OCT 15 PY 1998 VL 155 IS 4-6 BP 323 EP 326 DI 10.1016/S0030-4018(98)00385-X PG 4 WC Optics SC Optics GA 131YE UT WOS:000076602200019 ER PT J AU Johnson, M AF Johnson, M TI Theory of spin-dependent transport in ferromagnet-semiconductor heterostructures SO PHYSICAL REVIEW B LA English DT Article ID INVERSION-LAYERS; INJECTION; CHARGE AB The formalism of spin-dependent transport is used to calculate the conductance of device structures comprised of a two-dimensional electron-gas (2DEG) channel and ferromagnetic source and/or drain for a variety of magnetization configurations. Among the effects predicted by the calculations is spin-dependent current rectification at a 2DEG-ferromagnet interface. [S0163-1829(98)02036-0]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Johnson, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 14 TC 71 Z9 75 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD OCT 15 PY 1998 VL 58 IS 15 BP 9635 EP 9638 DI 10.1103/PhysRevB.58.9635 PG 4 WC Physics, Condensed Matter SC Physics GA 129WJ UT WOS:000076486800015 ER PT J AU Bayer, M Reinecke, TL Walck, SN Timofeev, VB Forchel, A AF Bayer, M Reinecke, TL Walck, SN Timofeev, VB Forchel, A TI Multiple resonances involving magnetoexcitons in a GaAs/Al0.30Ga0.70As quantum well SO PHYSICAL REVIEW B LA English DT Article ID EXCITON BINDING-ENERGY; MAGNETO-OPTICAL DETERMINATION; SEMICONDUCTORS; ABSORPTION; HOLE AB The excitonic states in an undoped GaAs/Al0.30Ga0.70As single quantum well have been studied by magnetophotoluminescence excitation spectroscopy at T=4.2 K. A series of regularly spaced steplike features is observed in the magnetic field dispersions of the transition energies of the excited heavy-hole excitons nshh, n=2,3,4. Correspondingly, the splitting between the two circular polarizations of the 2shh exciton shows pronounced oscillations as a function of magnetic field. We suggest that these features originate from the coupling of the transition between the ground state 1shh exciton and each of the excited states of the exciton with another excitation in the system. The energy difference between the features, which is about 7.5 meV, suggests that the excitation may be a transverse acoustic phonon with nonzero wave number near the zone boundary. [S0163-1829(98)01936-5]. C1 Univ Wurzburg, D-97074 Wurzburg, Germany. USN, Res Lab, Washington, DC 20375 USA. Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Russia. RP Bayer, M (reprint author), Univ Wurzburg, D-97074 Wurzburg, Germany. OI Forchel, Alfred/0000-0002-9377-9935 NR 17 TC 3 Z9 3 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD OCT 15 PY 1998 VL 58 IS 15 BP 9648 EP 9651 DI 10.1103/PhysRevB.58.9648 PG 4 WC Physics, Condensed Matter SC Physics GA 129WJ UT WOS:000076486800019 ER PT J AU Maltez, RL Liliental-Weber, Z Washburn, J Behar, M Klein, PB Specht, P Weber, ER AF Maltez, RL Liliental-Weber, Z Washburn, J Behar, M Klein, PB Specht, P Weber, ER TI Transmission electron microscopy and photoluminescence studies of Er implanted low-temperature grown GaAs : Be SO APPLIED PHYSICS LETTERS LA English DT Article ID ERBIUM-DOPED GAAS AB Characteristic 1.54 mu m 4f-4f emission has been observed from Er3+ centers in Er-implanted and annealed, low-temperature grown GaAs: Be samples, while cross-sectional transmission electron microscopy (TEM) studies reveal very little structural damage for elevated temperature implants. No Er emission was observed from any of the as-implanted samples, while the Er emission intensity was significantly more intense after 650 degrees C anneals than after 750 degrees C anneals. Significant enhancement of the optically active Er incorporation was achieved when the implantation was carried out at 300 degrees C. For the two total Er fluences employed (5.5x10(13) and 13.6x10(13) Er/cm(2)) the Er emission intensity exhibited a linear dependence upon implantation fluence, while TEM indicated no significant increase in the damage level at the higher fluence 300 degrees C implant. (C) 1998 American Institute of Physics. [S0003-6951(98)04641-5]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. UFRGS, Inst Fis, BR-91501970 Porto Alegre, RS, Brazil. USN, Res Lab, Washington, DC 20375 USA. Univ Calif Berkeley, Dept Mat Sci, Berkeley, CA 94720 USA. RP Maltez, RL (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012; Maltez, Rogerio/K-1173-2016 OI Maltez, Rogerio/0000-0002-8653-6118 NR 13 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 12 PY 1998 VL 73 IS 15 BP 2170 EP 2172 DI 10.1063/1.122412 PG 3 WC Physics, Applied SC Physics GA 128UX UT WOS:000076427700035 ER PT J AU Rommel, SL Dillon, TE Dashiell, MW Feng, H Kolodzey, J Berger, PR Thompson, PE Hobart, KD Lake, R Seabaugh, AC Klimeck, G Blanks, DK AF Rommel, SL Dillon, TE Dashiell, MW Feng, H Kolodzey, J Berger, PR Thompson, PE Hobart, KD Lake, R Seabaugh, AC Klimeck, G Blanks, DK TI Room temperature operation of epitaxially grown Si/Si0.5Ge0.5/Si resonant interband tunneling diodes SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; SB; SI; DIFFUSION; SI1-XGEX; INGAAS; FILMS AB Resonant interband tunneling diodes on silicon substrates are demonstrated using a Si/Si0.5Ge0.5/Si heterostructure grown by low temperature molecular beam epitaxy which utilized both a central intrinsic spacer and delta-doped injectors. A low substrate temperature of 370 degrees C was used during growth to ensure a high level of dopant incorporation. A B delta-doping spike lowered the barrier for holes to populate the quantum well at the valence band discontinuity, and an Sb delta-doping reduces the doping requirement of the n-type bulk Si by producing a deep n(+) well. Samples studied from the as-grown wafers showed no evidence of negative differential resistance (NDR). The effect of postgrowth rapid thermal annealing temperature was studied on tunnel diode properties. Samples which underwent heat treatment at 700 and 800 degrees C for 1 min, in contrast, exhibited NDR behavior. The peak-to-valley current ratio (PVCR) and peak current density of the tunnel diodes were found to depend strongly on delta-doping placement and on the annealing conditions. PVCRs ranging up to 1.54 were measured at a peak current density of 3.2 kA/cm(2). (C) 1998 American Institute of Physics. [S0003-6951(98)04841-4]. C1 Univ Delaware, Dept Elect & Comp Engn, Newark, DE 19716 USA. USN, Res Lab, Washington, DC 20375 USA. Raytheon Syst Co, Appl Res Lab, Dallas, TX 75243 USA. RP Berger, PR (reprint author), Univ Delaware, Dept Elect & Comp Engn, Newark, DE 19716 USA. EM pberger@ee.udel.edu RI Seabaugh, Alan/I-4473-2012; Rommel, Sean/F-9654-2013; Berger, Paul/I-4063-2014; Klimeck, Gerhard/A-1414-2012 OI Seabaugh, Alan/0000-0001-6907-4129; Rommel, Sean/0000-0001-5996-0813; Berger, Paul/0000-0002-2656-2349; Klimeck, Gerhard/0000-0001-7128-773X NR 20 TC 81 Z9 83 U1 1 U2 12 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 12 PY 1998 VL 73 IS 15 BP 2191 EP 2193 DI 10.1063/1.122419 PG 3 WC Physics, Applied SC Physics GA 128UX UT WOS:000076427700042 ER PT J AU Freeland, JW Bussmann, K Lubitz, P Idzerda, YU Cao, CC AF Freeland, JW Bussmann, K Lubitz, P Idzerda, YU Cao, CC TI Probing interfacial and bulk magnetic hysteresis in roughened CoFe thin films SO APPLIED PHYSICS LETTERS LA English DT Article ID X-RAY; 2ND-HARMONIC GENERATION; SCATTERING; MULTILAYERS; DICHROISM; IRON AB The hysteretic behavior of interfacial magnetic moments for CoFe thin films with varying roughness is determined in an element specific manner by monitoring the applied magnetic field dependence of the specular and off-specular (diffuse) contributions to the x-ray resonant magnetic scattering signal. Increasing the interfacial roughness generates a larger variation of the relative coercive field associated with the interfacial moment in comparison to the bulk. (C) 1998 American Institute of Physics. [S0003-6951(98)00941-3]. C1 USN, Res Lab, Washington, DC 20375 USA. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. Brookhaven Natl Lab, Naval Res Lab, Upton, NY 11973 USA. RP Freeland, JW (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM freeland@bnlls3.nsls.bnl.gov NR 24 TC 27 Z9 28 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 12 PY 1998 VL 73 IS 15 BP 2206 EP 2208 DI 10.1063/1.122424 PG 3 WC Physics, Applied SC Physics GA 128UX UT WOS:000076427700047 ER PT J AU Henderson, DR AF Henderson, DR TI Minimum wage plus $1 = more poverty SO FORTUNE LA English DT Editorial Material C1 USN, Postgrad Sch, Washington, DC 20350 USA. RP Henderson, DR (reprint author), USN, Postgrad Sch, Washington, DC 20350 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU TIME INC PI NEW YORK PA TIME & LIFE BUILDING ROCKEFELLER CENTER, NEW YORK, NY 10020-1393 USA SN 0015-8259 J9 FORTUNE JI Fortune PD OCT 12 PY 1998 VL 138 IS 7 BP 66 EP 66 PG 1 WC Business SC Business & Economics GA 122FV UT WOS:000076062000018 ER PT J AU Bashkansky, M Duncan, MD Goldberg, L Koplow, JP Reintjes, J AF Bashkansky, M Duncan, MD Goldberg, L Koplow, JP Reintjes, J TI Characteristics of a Yb-doped superfluorescent fiber source for use in optical coherence tomography SO OPTICS EXPRESS LA English DT Article AB We have used a newly developed Yb-doped high-power fiber source in an optical coherence tomography (OCT) apparatus. We have analyzed various properties of interest for OCT measurements such as spectral shape, related gate width, central wavelength, bandwidth, and power output. (C) 1998 Optical Society of America. C1 USN, Res Lab, Washington, DC 20375 USA. RP Bashkansky, M (reprint author), USN, Res Lab, Code 5642, Washington, DC 20375 USA. NR 12 TC 37 Z9 38 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD OCT 12 PY 1998 VL 3 IS 8 BP 305 EP 310 PG 6 WC Optics SC Optics GA 128WG UT WOS:000076430900002 PM 19384373 ER PT J AU Kapur, R Rudolph, AS AF Kapur, R Rudolph, AS TI Cellular and cytoskeleton morphology and strength of adhesion of cells on self-assembled monolayers of organosilanes SO EXPERIMENTAL CELL RESEARCH LA English DT Article ID HYDROPHILIC-HYDROPHOBIC COPOLYMERS; FLUID SHEAR-STRESS; ENDOTHELIAL-CELLS; SURFACES; GLASS; SUBSTRATE; GROWTH; SPECTROSCOPY; MICROSCOPY; APPARATUS AB objective of this study was to explore the potential use of self-assembled monolayers (SAMs) of alkylamine and arylalkyamine as well-defined, homogeneous, tailored in vitro model surfaces for exploring the effect of hydrodynamic flow on morphology and strength of adhesion of human umbilical vein endothelial cells. The cell surface area, shape, f-actin distribution, and adhesion strength of human umbilical vein endothelial cells cultured on self-assembled monolayers of organosilanes were found to be dependent on the chemical composition of the organosilane film and the magnitude of wall shear stress. The direct effects of the differences in chemistry between the two silanes, in modulating cellular response, are probably only secondary to the modulation of cellular functions mediated by differential protein adsorption and conformation on the two silanes. For short seeding times (30 min), prior to application of flow, both substrate chemistry and shear stress modulated the cellular morphology and cytoskeletal organization. For longer seeding times (24 h), prior to application of flow, the chemistry of the underlying surface was the dominant variable in modulating cellular morphology, while the hydrodynamic shear stress modulated the cytoskeleton organization. Cells on N-(2-aminoethyl)-3-aminopropyl trimethoxysilane (EDA) were pleomorphic, while cells on ((((aminoethyl)amino)methyl)phenylethyl)trimethoxysilane (PEDA) expressed a rounded morphology. Application of an incrementally loaded how regime (0.07-1.25 ml/s) resulted in a time- and shear stress-dependent (10-180 dyn/cm(2)) detachment of cells, with the cells on EDA depicting higher resistance to wall shear stress. Cellular morphology correlated with the strength of adhesion; cells with rounded morphology on a hydrophobic silane, PEDA, were less tightly bound to the silane, while spread cells on a hydrophilic silane, EDA, were more tightly bound. The higher surface free energy of EDA is speculated to influence the increased cell spreading and strength of adhesion observed in these studies. The presence of the phenyl group in PEDA reduces the surface free energy and may account for the reduced spreading and lower strength of adhesion. The use of well-defined systems, such as monolayer organosilanes, with tunable surface physicochemical properties may serve to deconstruct the complex interaction of cells with extracellular matrix components: surface charge, surface hydrophobicity, and other short- and long-range forces can be individually controlled and correlated with cellular functions, The organosilane monolayers could serve as the building blocks for sequential addition of proteins or cell adhesive/cell repulsive cues to stepwise engineering and construction of more complex systems resembling ECM matrices, (C) 1998 Academic Press. C1 George Mason Univ, Ctr Bioresource Dev, Fairfax, VA 22030 USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Kapur, R (reprint author), CELLOMICS Inc, 635 William Pitt Way, Pittsburgh, PA 15238 USA. NR 33 TC 44 Z9 45 U1 1 U2 10 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0014-4827 J9 EXP CELL RES JI Exp. Cell Res. PD OCT 10 PY 1998 VL 244 IS 1 BP 275 EP 285 DI 10.1006/excr.1998.4156 PG 11 WC Oncology; Cell Biology SC Oncology; Cell Biology GA 130BL UT WOS:000076499300028 PM 9770370 ER PT J AU Leoni, M Jones, RL Scardi, P AF Leoni, M Jones, RL Scardi, P TI Phase stability of scandia-yttria-stabilized zirconia TBCs SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 25th International Conference on Metallurgical Coatings and Thin Films CY APR 25-MAY 01, 1998 CL SAN DIEGO, CALIFORNIA SP Vacuum Met, Thin Film Div, AVS DE stabilized zirconia; phase transformation; X-ray diffraction; thermal barrier coatings; Rietveld method ID THERMAL BARRIER COATINGS; TRANSFORMATION; SYSTEMS AB The evolution in phase composition resulting from 1400 degrees C ageing of ZrO2 samples stabilized by similar to 4-7 mol.% each of Y2O3 (YSZ), Sc2O3 (ScSZ), or a mixture of Sc2O3-Y2O3 (SYSZ) was studied by synchrotron radiation X-ray diffraction (SR XRD) using whole powder pattern fitting (WPPF), a recently proposed Rietveld-based method for the simultaneous refinement of phase composition and crystal microstructure. The results suggest that SYSZ has better high temperature tetragonal phase stability than the current state-of-art YSZ. For example, a plasma-sprayed coating of SYSZ (6.57 mol.%Sc2O3-1.00 mol.%Y2O3) remained 96.7% in its original tetragonal phase (presumably t', c/a of 1.0058) after being aged 100 h at 1400 degrees C and then 24 h at 1480 degrees C, whereas a 4.5 mol.% YSZ coating was transformed into two new tetragonal phases, one a low-stabilizer phase with cia of 1.0154 (44.8%) and the other a high-stabilizer zirconia phase with c/a of 1.003 (46.5%), with some monoclinic (8.7%) formed. The phase compositions found for the various powder and coating specimens, together with information regarding lattice parameters, crystalline domain size and microstrain, also obtained by WPPF, are discussed in terms of the high-temperature phase stability of the YSZ vs SYSZ systems. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Trent, Dipartimento Ingn Mat, I-38050 Mesiano, TN, Italy. USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Scardi, P (reprint author), Univ Trent, Dipartimento Ingn Mat, I-38050 Mesiano, TN, Italy. EM Paolo.Scardi@ing.unitn.it RI Leoni, Matteo/A-9634-2010; Scardi, Paolo/E-2085-2014 OI Leoni, Matteo/0000-0002-2030-1711; NR 14 TC 48 Z9 58 U1 1 U2 15 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD OCT 10 PY 1998 VL 108 IS 1-3 BP 107 EP 113 DI 10.1016/S0257-8972(98)00617-3 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 142LY UT WOS:000077203000017 ER PT J AU Thomas, JB Zheng, XL Mascarella, SW Rothman, RB Dersch, CM Partilla, JS Flippen-Anderson, JL George, CF Cantrell, BE Zimmerman, DM Carroll, FI AF Thomas, JB Zheng, XL Mascarella, SW Rothman, RB Dersch, CM Partilla, JS Flippen-Anderson, JL George, CF Cantrell, BE Zimmerman, DM Carroll, FI TI N-substituted 9 beta-methyl-5-(3-hydroxyphenyl)morphans are opioid receptor pure antagonists SO JOURNAL OF MEDICINAL CHEMISTRY LA English DT Article ID LIGAND AB The inhibition of radioligand binding and [S-35]GTP gamma S functional assay data for N-methyl- and N-phenethyl-9 beta-methyl-5-(3-hydroxyphenyl (5b and 5c) show that these compounds are pure antagonists at the mu, delta, and kappa opioid receptors. Since 5b and 5c have the 5-(3-hydroxyphenyl) group locked in a conformation comparable to an equatorial group of a piperidine chair conformation, this information provides very strong evidence that opioid antagonists can interact with opioid receptors in this conformation. In addition, it suggests that the trans-3,4-dimethyl-4-(3-hydroxyphenyl)piperidine class of antagonist operates via a phenyl equatorial piperidine chair conformation. Importantly, the close relationship between the 4-(3-hydroxyphenyl)piperidines and 5-(3-hydroxyphenyl)morph an antagonists shows that the latter class of compound provides a rigid platform on which to build a novel series of opioid antagonists. C1 Res Triangle Inst, Res Triangle Pk, NC 27709 USA. NIDA, Addict Res Sect, Clin Psychopharmacol Sect, Baltimore, MD 21224 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. Eli Lilly & Co, Lilly Corp Ctr, Lilly Res Labs, Indianapolis, IN 46285 USA. RP Carroll, FI (reprint author), Res Triangle Inst, POB 12194, Res Triangle Pk, NC 27709 USA. OI Mascarella, Wayne/0000-0003-0092-8178 FU NIDA NIH HHS [DA09045] NR 23 TC 22 Z9 23 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-2623 J9 J MED CHEM JI J. Med. Chem. PD OCT 8 PY 1998 VL 41 IS 21 BP 4143 EP 4149 DI 10.1021/jm980290i PG 7 WC Chemistry, Medicinal SC Pharmacology & Pharmacy GA 127WV UT WOS:000076374300022 PM 9767649 ER PT J AU Kaye, FJ AF Kaye, FJ TI The retinoblastoma-like protein family: Still in the shadow of the RB gene? SO JOURNAL OF THE NATIONAL CANCER INSTITUTE LA English DT Editorial Material ID LARGE T-ANTIGEN; GROWTH SUPPRESSION; P107; PRODUCT; SIMIAN-VIRUS-40; P130; MEMBERS; CLONING; TUMORS; DOMAIN C1 Natl Naval Med Ctr, Bethesda, MD USA. NCI, Metab Branch, Div Clin Sci, Bethesda, MD 20892 USA. RP Kaye, FJ (reprint author), USN Hosp, Bldg 8,Rm 5101, Bethesda, MD 20889 USA. RI kaye, frederic/E-2437-2011 NR 25 TC 1 Z9 1 U1 0 U2 1 PU NATL CANCER INSTITUTE PI BETHESDA PA 9030 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0027-8874 J9 J NATL CANCER I JI J. Natl. Cancer Inst. PD OCT 7 PY 1998 VL 90 IS 19 BP 1418 EP 1419 DI 10.1093/jnci/90.19.1418 PG 2 WC Oncology SC Oncology GA 127QV UT WOS:000076362800002 PM 9776402 ER PT J AU Mott, PH Roland, CM AF Mott, PH Roland, CM TI Birefringence of polymers in the softening zone SO MACROMOLECULES LA English DT Article ID AMORPHOUS POLYMERS; VISCOELASTIC PROPERTIES; THERMORHEOLOGICAL COMPLEXITY; DYNAMIC BIREFRINGENCE; PLASTIC-DEFORMATION; POLYISOBUTYLENE; POLYSTYRENE; RELAXATION; BEHAVIOR; STRESS C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Roland, CM (reprint author), USN, Res Lab, Div Chem, Code 6120, Washington, DC 20375 USA. NR 26 TC 16 Z9 16 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 6 PY 1998 VL 31 IS 20 BP 7095 EP 7098 DI 10.1021/ma980174p PG 4 WC Polymer Science SC Polymer Science GA 128DE UT WOS:000076389300044 ER PT J AU Papanicolaou, NA Edwards, A Rao, MV Anderson, WT AF Papanicolaou, NA Edwards, A Rao, MV Anderson, WT TI Si/Pt Ohmic contacts to p-type 4H-SiC SO APPLIED PHYSICS LETTERS LA English DT Article AB In this letter, we report on the investigation of Si/Pt Ohmic contacts to p-type 4H-SiC. The contacts were formed by a vacuum annealing method at 1100 degrees C for 3 min, which resulted in specific contact resistivities in the low 10(-4) Ohm cm(2) range. Auger analysis has shown that, at this anneal temperature, there was a uniform intermixing of the Si and Pt, migration of Pt into the SiC, and out-diffusion of C into the metallization layers. Overlayers of Au or Ni/Au on Si/Pt had the effect of decreasing the specific contact resistance and improving the surface morphology of the annealed contacts. (C) 1998 American Institute of Physics. [S0003-6951(98)03240-9]. C1 USN, Res Lab, Washington, DC 20375 USA. George Mason Univ, Dept Elect & Comp Engn, Fairfax, VA 22030 USA. RP USN, Res Lab, Washington, DC 20375 USA. NR 9 TC 17 Z9 17 U1 0 U2 2 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 OCT 5 PY 1998 VL 73 IS 14 BP 2009 EP 2011 DI 10.1063/1.122351 PG 3 WC Physics, Applied SC Physics GA 124LF UT WOS:000076183300029 ER PT J AU Koleske, DD Wickenden, AE Henry, RL Twigg, ME Culbertson, JC Gorman, RJ AF Koleske, DD Wickenden, AE Henry, RL Twigg, ME Culbertson, JC Gorman, RJ TI Enhanced GaN decomposition in H-2 near atmospheric pressures SO APPLIED PHYSICS LETTERS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; SAPPHIRE; LAYERS AB GaN decomposition is studied at metallorganic vapor phase epitaxy pressures (i.e., 10-700 Torr) in flowing H-2. For temperatures ranging from 850 to 1050 degrees C, the GaN decomposition rate is accelerated when the H-2 pressure is increased above 100 Torr. The Ga desorption rate is found to be independent of pressure, and therefore, does not account for the enhanced GaN decomposition rate. Instead, the excess Ga from the decomposed GaN forms droplets on the surface which, for identical annealing conditions, increase in size as the pressure is increased. Possible connections between the enhanced GaN decomposition rate, the coarsening of the nucleation layer during the ramp to high temperature, and increased GaN grain size at high temperature are discussed. [S0003-6951(98)03540-2]. C1 USN, Res Lab, Lab Adv Mat Synth, Div Elect Sci & Technol, Washington, DC 20375 USA. RP Koleske, DD (reprint author), USN, Res Lab, Lab Adv Mat Synth, Div Elect Sci & Technol, Code 6861, Washington, DC 20375 USA. EM koleske@estd.nrl.navy.mil NR 25 TC 61 Z9 62 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 5 PY 1998 VL 73 IS 14 BP 2018 EP 2020 DI 10.1063/1.122354 PG 3 WC Physics, Applied SC Physics GA 124LF UT WOS:000076183300032 ER PT J AU Zhao, XZ Bharti, V Zhang, QM Romotowski, T Tito, F Ting, R AF Zhao, XZ Bharti, V Zhang, QM Romotowski, T Tito, F Ting, R TI Electromechanical properties of electrostrictive poly(vinylidenefluoride-trifluoroethylene) copolymer SO APPLIED PHYSICS LETTERS LA English DT Article ID FLUORIDE AB We report a large electrostrictive strain in electron irradiated poly(vinylidene fluoride-trifluoroethylene) copolymer at a composition with 65 mol % vinylidene fluoride, which also exhibits a large ratio of strain to applied field (similar to 275 pm/V). The strain response is nearly independent of the external driving condition (unipolar or bipolar field) and does not change with temperature in about 20 degrees C temperature range near room temperature. Moreover, near room temperature, the material can reach a relatively high quasistatic longitudinal electromechanical coupling factor k(33)similar to 0.33. (C) 1998 American Institute of Physics. [S0003-6951(98)03040-X]. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Penn State Univ, Dept Elect Engn, University Pk, PA 16802 USA. USN, Undersea Warfare Ctr, Newport, RI 02841 USA. Univ Cent Florida, Dept Chem, Orlando, FL 32816 USA. RP Zhang, QM (reprint author), Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. NR 9 TC 71 Z9 74 U1 3 U2 13 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 5 PY 1998 VL 73 IS 14 BP 2054 EP 2056 DI 10.1063/1.122365 PG 3 WC Physics, Applied SC Physics GA 124LF UT WOS:000076183300044 ER PT J AU Ramaker, DE Mojet, BL Koningsberger, DC O'Grady, WE AF Ramaker, DE Mojet, BL Koningsberger, DC O'Grady, WE TI Understanding atomic x-ray absorption fine structure in x-ray absorption spectra SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID EMBEDDED ATOMS AB The origin and important parameters determining the intensity of atomic x-ray absorption fine structure (AXAFS) are described both in chemical and physical terms. A full mathematical derivation is presented and new criteria are given for removal of the background to extract the total chi (EXAFS and AXAFS) from the experimental absorption cross-section. The embedded-atom potential, the interstitial potential and the distribution of the absorber-atom electron density are all found to be important in determining the AXAFS intensity. Application is made to spherical Pt metal clusters, where it is shown that the AXAFS intensity of the central atom is much larger than that of the surface atoms. However, the average AXAFS intensity per platinum atom is found not to depend significantly on cluster size. On the other hand, variation of the metal cluster support does considerably change the intensity as well as the imaginary part of the AXAFS. Hence, AXAFS can be a very useful probe of the effects of metal-support interactions in supported noble-metal catalysts. C1 George Washington Univ, Dept Chem, Washington, DC 20052 USA. George Washington Univ, Inst Sci Mat, Washington, DC 20052 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. Univ Utrecht, Dept Inorgan Chem, Dept Inorgan Chem, NL-3508 TB Utrecht, Netherlands. RP Ramaker, DE (reprint author), George Washington Univ, Dept Chem, Washington, DC 20052 USA. EM ramaker@gwu.edu RI Institute (DINS), Debye/G-7730-2014 NR 18 TC 52 Z9 53 U1 2 U2 9 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD OCT 5 PY 1998 VL 10 IS 39 BP 8753 EP 8770 DI 10.1088/0953-8984/10/39/013 PG 18 WC Physics, Condensed Matter SC Physics GA 129ZB UT WOS:000076493000013 ER PT J AU Robinson, JWC Asraf, DE Bulsara, AR Inchiosa, ME AF Robinson, JWC Asraf, DE Bulsara, AR Inchiosa, ME TI Information-theoretic distance measures and a generalization of stochastic resonance SO PHYSICAL REVIEW LETTERS LA English DT Article ID NOISE AB We show that stochastic resonance (SR)-like phenomena in a nonlinear system can be described in terms of maximization of information-theoretic distance measures between probability distributions of the output variable or, equivalently, via a minimum probability of error in detection. This offers a new and unifying framework for SR-like phenomena in which the "resonance" becomes independent of the specific method used to measure it, the static or dynamic character of the nonlinear device in which it occurs, and the nature of the input signal. Our approach also provides fundamental limits of performance and yields an alternative set of design criteria for optimization of the information processing capabilities of nonlinear devices. C1 Natl Def Res Estab, FOA, S-17290 Sundbyberg, Sweden. USN, Space & Warfare Syst Ctr, San Diego, CA 92152 USA. RP Robinson, JWC (reprint author), Natl Def Res Estab, FOA, S-17290 Sundbyberg, Sweden. NR 16 TC 29 Z9 29 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 5 PY 1998 VL 81 IS 14 BP 2850 EP 2853 DI 10.1103/PhysRevLett.81.2850 PG 4 WC Physics, Multidisciplinary SC Physics GA 125HR UT WOS:000076231900004 ER PT J AU Shirron, JJ Babuska, I AF Shirron, JJ Babuska, I TI A comparison of approximate boundary conditions and infinite element methods for exterior Helmholtz problems SO COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING LA English DT Article; Proceedings Paper CT Mini Symposium on Exterior Problems of Wave Propagation at the 4th US National Congress on Computational Mechanics CY AUG, 1997 CL SAN FRANCISCO, CALIFORNIA ID WAVE ENVELOPE ELEMENTS; ACOUSTICAL RADIATION; INTEGRAL-EQUATIONS; FINITE-ELEMENTS; SCATTERING; SCHEMES AB We compare the accuracy of a variety of approximate boundary conditions (ABCs) and two versions of an infinite element method (IEM) for approximating solutions of exterior Helmholtz problems. The infinite elements are of variable order in the radial direction and differ only in whether the test functions in the weak formulation are conjugated or not. We find that the accuracy of the ABCs decreases with increasing frequency, and that at higher frequencies their accuracy is several orders of magnitude lower than that obtained with the IEMs. We show that the convergence rate of the conjugated element is slower than the rate for the unconjugated element and that the latter element fails to converge in the far field. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Texas, TICAM, Austin, TX 78712 USA. RP Shirron, JJ (reprint author), USN, Res Lab, Code 7131, Washington, DC 20375 USA. NR 59 TC 69 Z9 69 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0045-7825 J9 COMPUT METHOD APPL M JI Comput. Meth. Appl. Mech. Eng. PD OCT 2 PY 1998 VL 164 IS 1-2 BP 121 EP 139 DI 10.1016/S0045-7825(98)00050-4 PG 19 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA 134WV UT WOS:000076767500008 ER PT J AU Zeisler-Mashl, KL Francavilla, TL Pande, CS AF Zeisler-Mashl, KL Francavilla, TL Pande, CS TI Characterization of high critical temperature superconducting wires SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article DE superconductors; BSCCO tape; c-axis texture ID CRITICAL-CURRENT-DENSITY; CURRENT FLOW; TAPES; CONDUCTOR; COILS AB Improvements in the current transport properties of high critical temperature superconductors would be facilitated by a quantitative description of the relationship between current capacity and superconductor microstructures. In this study, three types of silver-Bi2212 tapes were characterized in terms of critical current density and various microstructural features. Tapes given melt processing treatments were found to have a higher critical current density, larger apparent Bi2212 grain size, and stronger c-axis texture compared to the results of a lower temperature treatment. A comparison of (001) pole figure data and current transport measurements indicated that a 3-fold increase in the c-axis angular spread corresponded to an order of magnitude drop in critical current density. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. RP Zeisler-Mashl, KL (reprint author), USN, Res Lab, Div Mat Sci & Technol, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5107 J9 MAT SCI ENG B-SOLID JI Mater. Sci. Eng. B-Solid State Mater. Adv. Technol. PD OCT 2 PY 1998 VL 56 IS 1 BP 53 EP 59 DI 10.1016/S0921-5107(98)00257-8 PG 7 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 137BD UT WOS:000076892800008 ER PT J AU Soulen, RJ Byers, JM Osofsky, MS Nadgorny, B Ambrose, T Cheng, SF Broussard, PR Tanaka, CT Nowak, J Moodera, JS Barry, A Coey, JMD AF Soulen, RJ Byers, JM Osofsky, MS Nadgorny, B Ambrose, T Cheng, SF Broussard, PR Tanaka, CT Nowak, J Moodera, JS Barry, A Coey, JMD TI Measuring the spin polarization of a metal with a superconducting point contact SO SCIENCE LA English DT Article ID FERROMAGNET; FILMS; CRO2; TRANSITION; FE AB A superconducting point contact is used to determine the spin polarization at the Fermi energy of several metals. Because the process of supercurrent conversion at a superconductor-metal interface (Andreev reflection) is limited by the minority spin population near the Fermi surface, the differential conductance of the point contact can reveal the spin polarization of the metal. This technique has been applied to a variety of metals where the spin polarization ranges from 35 to 90 percent: Ni0.8Fe0.2, Ni, Co, Fe, NiMnSb, La0.7Sr0.3MnO3, and CrO2. C1 George Washington Univ, Dept Phys, Washington, DC 20052 USA. USN, Res Lab, Washington, DC 20375 USA. MIT, Francis Bitter Natl Magnet Lab, Cambridge, MA 02139 USA. Univ Dublin Trinity Coll, Dept Phys, Dublin 2, Ireland. RP Byers, JM (reprint author), George Washington Univ, Dept Phys, Washington, DC 20052 USA. EM byers@foucault.nrl.navy.mil RI Osofsky, Michael/A-1050-2010 NR 19 TC 1152 Z9 1165 U1 11 U2 115 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD OCT 2 PY 1998 VL 282 IS 5386 BP 85 EP 88 DI 10.1126/science.282.5386.85 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 126LM UT WOS:000076294900042 ER PT J AU Buckley, RG King, KJ Disney, JD Ambroz, PK Gorman, JD Klausen, JH AF Buckley, RG King, KJ Disney, JD Ambroz, PK Gorman, JD Klausen, JH TI Derivation of a clinical prediction model for the emergency department diagnosis of ectopic pregnancy SO ACADEMIC EMERGENCY MEDICINE LA English DT Article DE ectopic pregnancy; prediction model; abdominal pain; vaginal bleeding ID HUMAN CHORIONIC-GONADOTROPIN; IN-VITRO FERTILIZATION; VAGINAL SONOGRAPHY; RISK-FACTORS; EMBRYO-TRANSFER; INTRAUTERINE; EPIDEMIOLOGY; ACCURACY AB Objective: To derive a clinical prediction model for estimating the pretest probability of ectopic pregnancy in ED patients with first-trimester abdominal pain or vaginal bleeding. Methods: All hemodynamically stable first-trimester patients presenting to the ED of a tertiary care military teaching hospital over a 14-month period with a chief complaint of abdominal pain and/or vaginal bleeding had clinical data coded prior to determining outcome. They were then followed longitudinally until a criterion standard pregnancy outcome was established. Results: Of the 486 patients enrolled, 280 (58%) had viable intrauterine pregnancies, 167 (34%) had nonviable intrauterine pregnancies, and 39 (8%) had ectopic pregnancies. Using a recursive partitioning model, a high-risk group was derived (that was separated from intermediate and low-risk groups), consisting of patients with abdominal peritoneal signs or definite cervical motion tenderness, with a sensitivity of 31% (95% CI: 17-48%), a specificity of 93% (95% CI: 90-95%), a positive likelihood ratio of 4.3, and a negative likelihood ratio of 0.74. A low-risk group, consisting of patients with either fetal heart tones or tissue at the cervical os, or the absence of pain other than midline menstrual-like cramping and lacking any pelvic tenderness, was differentiated from an intermediate-risk group, with a sensitivity of 96% (95% CI: 81-100%), a specificity of 22% (95% CI: 18-26%), a positive likelihood ratio of 1.2, and a negative likelihood ratio of 0.17. Conclusion: A clinical prediction model for estimating the probability of ectopic pregnancy in ED patients has been derived. It may prove to have practical clinical application for estimating pretest probability of ectopic pregnancy as well as assisting in medical decision making when laboratory and ultrasonographic findings are nondiagnostic. Clinical application should await prospective validation in an independent sample. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Radiol, San Diego, CA 92134 USA. USN, Med Ctr, Dept Emergency Med, San Diego, CA 92134 USA. USN, Med Ctr, Dept Obstet & Gynecol, San Diego, CA 92134 USA. RP Buckley, RG (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. EM nasjleti@sndl0.med.navy.mil NR 41 TC 25 Z9 25 U1 0 U2 0 PU HANLEY & BELFUS INC PI PHILADELPHIA PA 210 S 13TH ST, PHILADELPHIA, PA 19107 USA SN 1069-6563 J9 ACAD EMERG MED JI Acad. Emerg. Med. PD OCT PY 1998 VL 5 IS 10 BP 951 EP 960 PG 10 WC Emergency Medicine SC Emergency Medicine GA 128PL UT WOS:000076415000004 PM 9862584 ER PT J AU Chandrasekhara, MS Wilder, MC Carr, LW AF Chandrasekhara, MS Wilder, MC Carr, LW TI Unsteady stall control using dynamically deforming airfoils SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 15th Applied Aerodynamics Conference CY JUN 23-25, 1997 CL ATLANTA, GEORGIA SP Amer Inst Aeronaut & Astronaut AB An experiment documenting the compressible flow over a dynamically deforming airfoil is presented. This airfoil, which has a leading edge radius that can be dynamically changed, was tested at various deformation rates for fixed airfoil angle of attack. Selected leading-edge shapes were also tested during airfoil oscillation. These tests show that for a range of Mach numbers observed on the retreating blades of helicopter rotors the dynamic stall vortex can be avoided by a judicious variation of leading-edge curvature. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. USN, Postgrad Sch, Navy NASA Joint Inst Aeronaut, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. MCAT Inc, Navy NASA Joint Inst Aeronaut, Mt View, CA 94043 USA. RP Chandrasekhara, MS (reprint author), NASA, Ames Res Ctr, MS 260-1, Moffett Field, CA 94035 USA. NR 9 TC 26 Z9 26 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD OCT PY 1998 VL 36 IS 10 BP 1792 EP 1800 DI 10.2514/2.294 PG 9 WC Engineering, Aerospace SC Engineering GA 126VQ UT WOS:000076315500004 ER PT J AU Robinson, DF Hassan, HA AF Robinson, DF Hassan, HA TI Further development of the k-zeta (enstrophy) turbulence closure model SO AIAA JOURNAL LA English DT Article AB The k-zeta model is extended to the study of two-dimensional and three-dimensional separated external flows where Morkovin's hypothesis is expected to hold. The resulting model is free of damping and wall functions and is coordinate independent. Further, all modeled correlations are tensorially consistent and Galilean invariant. Applications include a variety of separated flows over airfoils and a cylinder/offset flare juncture. Comparisons are made with other turbulence models and experiment. In general, good agreement with experiment is indicated. The results demonstrate that it is possible to develop a two-equation turbulence model that is capable of predicting separated flows without sacrificing performance for free shear layers. C1 N Carolina State Univ, Raleigh, NC 27695 USA. RP Robinson, DF (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Code G72, Dahlgren, VA 22448 USA. NR 20 TC 28 Z9 28 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD OCT PY 1998 VL 36 IS 10 BP 1825 EP 1833 DI 10.2514/2.298 PG 9 WC Engineering, Aerospace SC Engineering GA 126VQ UT WOS:000076315500008 ER PT J AU Brook, I Frazier, EH AF Brook, I Frazier, EH TI Aerobic and anaerobic microbiology of infection after trauma SO AMERICAN JOURNAL OF EMERGENCY MEDICINE LA English DT Review DE trauma; anaerobic bacteria; Staphylococcus aureus; wounds; abscesses ID NECROTIZING FASCIITIS AB Clinical and laboratory data from 1973 to 1988 were retrospectively reviewed to study the microbiology of infection following trauma. A total of 368 specimens obtained from 340 trauma patients showed bacterial growth. The traumas included lacerations (163), blunt trauma (76), penetrating trauma (65), bites (20), and open fractures (10). Anaerobic bacteria only were isolated in 119 (32%) specimens, aerobic bacteria only in 58 (16%), and mixed aerobic-anaerobic flora in 191 (52%). A total of 444 anaerobic (1.2 isolates per specimen) and 267 aerobic or facultative (0.7 per specimen) were recovered. The predominant anaerobic bacteria included Bacteroides fragilis group (119 isolates), Peptostreptococcus spp (113), Clostridium spp (78), Prevotella spp (58), and Fusobacterium spp (23). The predominant aerobic bacteria included Escherichia coli (83), Staphylococcus aureus (61), Streptococcus pyogenes (27), Streptococcus group D (16), and Klebsiella pneumoniae (16). The types of infections included abscesses (109), bacteremia (32), bites (13), empyema (10), osteomyelitis (21), peritonitis (52), thrombophlebitis (12), and wounds (116, including posttraumatic wounds, cellulitis, stump wound, decubitus ulcers, myositis, and fasciitis). S aureus was isolated at all sites. However, organisms of the oropharyngeal flora predominated in infections that originated from that location (ie, head and neck wounds, and abscesses or bites), and those of the gastrointestinal flora predominated in infections that originated from that site (ie, peritonitis, abdominal abscesses, decubitus ulcers). This study showed the polymicrobial nature of many infections that follow trauma. (Am J Emerg Med 1998;16: 585-591. This is a US government work. There are no restrictions on its use.). C1 USN Hosp, Dept Pediat, Bethesda, MD USA. RP Brook, I (reprint author), POB 70412, Chevy Chase, MD 20813 USA. NR 16 TC 33 Z9 35 U1 1 U2 1 PU W B SAUNDERS CO-ELSEVIER INC PI PHILADELPHIA PA 1600 JOHN F KENNEDY BOULEVARD, STE 1800, PHILADELPHIA, PA 19103-2899 USA SN 0735-6757 EI 1532-8171 J9 AM J EMERG MED JI Am. J. Emerg. Med. PD OCT PY 1998 VL 16 IS 6 BP 585 EP 591 DI 10.1016/S0735-6757(98)90225-X PG 7 WC Emergency Medicine SC Emergency Medicine GA 127WG UT WOS:000076373100010 PM 9786544 ER PT J AU Higgins, JC Kiser, WR McClenathan, S Tynan, NL AF Higgins, JC Kiser, WR McClenathan, S Tynan, NL TI Influence of an interventional program on resource use and cost in pediatric asthma SO AMERICAN JOURNAL OF MANAGED CARE LA English DT Article ID UNITED-STATES; MANAGEMENT; CHILDREN; CARE; CANADA; RATES; DEATH AB Objective: Asthma is the most common chronic Condition of childhood, for which morbidity, mortality, and cost are increasing. This study was performed to determine whether patient education and assignment to a primary care provider improve outcomes and cost in the management of pediatric asthma. Study Design: A prospective pilot study of 61 patients was conducted with a retrospective review. Data were obtained from health and pharmacy records. Patients and Methods: Sixty-one unassigned pediatric asthma patients who were noted to be frequent users of emergency department services and who had no primary care provider were identified. This cohort received asthma education and was assigned a provider trained in the national asthma guidelines. Hospital admissions, Emergency Department and clinic visits, use of BZ agonists and anti-inflammatory drugs, number of chest radiographs, and continuity of care were recorded for a mean of 58.1 months before and 11.2 months after the intervention. A cost analysis was done. Results: All measured parameters showed favorable changes after intervention, with the decrease in the number of prescriptions of monthly inhaled antiinflammatory drugs and chest radiographs ordered being statistically significant (P = 0.007 and P = 0.040, respectively). Monthly admissions, Emergency Department visits, and clinic visits declined after intervention when evaluated after 22.8 months of follow up. Annual resource savings after intervention was estimated to be $4845.29 per patient for this military hospital. Conclusions: A combined intervention consisting of provider and patient education and assignment to a primary care provider was associated with improved care and economic outcomes in this group. C1 USN Hosp, Dept Family Practice, CDR MC, Jacksonville, FL 32214 USA. USN Hosp, Dept Pediat, Jacksonville, FL 32214 USA. USN Hosp, Dept Pharm, Jacksonville, FL 32214 USA. RP Higgins, JC (reprint author), USN Hosp, Dept Family Practice, CDR MC, 2080 Child St, Jacksonville, FL 32214 USA. NR 22 TC 17 Z9 18 U1 0 U2 5 PU AMER MED PUBLISHING, M W C COMPANY PI OLD BRIDGE PA 1816 ENGLISHTOWN RD, STE 101, OLD BRIDGE, NJ 08857 USA SN 1088-0224 J9 AM J MANAG CARE JI Am. J. Manag. Care PD OCT PY 1998 VL 4 IS 10 BP 1465 EP 1469 PG 5 WC Health Care Sciences & Services; Health Policy & Services; Medicine, General & Internal SC Health Care Sciences & Services; General & Internal Medicine GA 135PW UT WOS:000076812600008 PM 10338738 ER PT J AU Magann, EF McNamara, MF Whitworth, NS Chauhan, SP Thorpe, RA Morrison, JC AF Magann, EF McNamara, MF Whitworth, NS Chauhan, SP Thorpe, RA Morrison, JC TI Can we decrease postdatism in women with an unfavorable cervix and a negative fetal fibronectin test result at term by serial membrane sweeping? SO AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY LA English DT Article; Proceedings Paper CT 18th Annual Meeting of the Society-of-Perinatal-Obstetricians CY FEB 02-07, 1998 CL MIAMI, FLORIDA SP Soc Perinatal Obstetricians DE postdatism; unfavorable cervix; membrane sweeping; fetal fibronectin ID POSTTERM PREGNANCIES; INDUCTION; LABOR; PREDICTOR; REDUCE; SAFE AB OBJECTIVE: Our purpose was to determine whether the risk for postdatism can be reduced by serial membrane sweeping in women with an unfavorable cervix at 39 weeks' gestation and a negative fetal fibronectin test result. STUDY DESIGN: Women with uncomplicated pregnancies, who were candidates for a vaginal delivery with an unfavorable cervix at 39 weeks' gestation and a negative fetal fibronectin test result were asked to participate in this investigation. Patients were chosen at random and assigned to a group for membrane sweeping every 3 days or to a control group who received gentle examinations every 3 days. RESULTS: Sixty-five women were selected at random for serial membrane sweeping (n = 33) or for the control group (n = 32). Although gestational age and Bishop score at study entry were similar, the gestational age on admission for delivery was earlier in the membrane sweeping group (39.9 +/- 0.3) versus the control group (41.5 +/- 0.6, P < .0001). The Bishop score on admission to labor and delivery was greater (8.8 +/- 2.1) in the membrane sweeping group than in the control group (6.2 +/- 2.7, P < .0001). The number of women admitted for labor inductions at 42 weeks' gestation was 18 of 32 (56%) in the control group versus none (0 of 24) in the membrane-sweeping group (P < .0001). CONCLUSIONS: Women with an unfavorable cervix at 39 weeks' gestation and a negative fetal fibronectin test result are at risk for not being delivered by 41 completed weeks and thus may require postdates induction or antenatal testing. Serial membrane sweeping significantly reduces the risk of postdatism and induction of labor. C1 USN, Med Ctr, Dept Obstet & Gynecol, San Diego, CA 92152 USA. Med Coll Georgia, Dept Obstet & Gynecol, Augusta, GA 30912 USA. Univ Mississippi, Med Ctr, Dept Obstet & Gynecol, University, MS 38677 USA. RP Magann, EF (reprint author), USN, Med Ctr, Dept Obstet & Gynecol, San Diego, CA 92152 USA. NR 15 TC 10 Z9 10 U1 0 U2 1 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0002-9378 J9 AM J OBSTET GYNECOL JI Am. J. Obstet. Gynecol. PD OCT PY 1998 VL 179 IS 4 BP 890 EP 894 DI 10.1016/S0002-9378(98)70184-X PG 5 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 129RC UT WOS:000076475900010 PM 9790365 ER PT J AU Fryauff, DJ Tuti, S Mardi, A Masbar, S Patipelohi, R Leksana, B Kain, KC Bangs, MJ Richie, TL Baird, JK AF Fryauff, DJ Tuti, S Mardi, A Masbar, S Patipelohi, R Leksana, B Kain, KC Bangs, MJ Richie, TL Baird, JK TI Chloroquine-resistant Plasmodium vivax in transmigration settlements of West Kalimantan, Indonesia SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID IRIAN-JAYA; MALARIA RESISTANT; FALCIPARUM AB Malariometric surveys were conducted during July 1996 in native Dayak villages and predominantly Javanese transmigration settlements in Ketapang district of West Kalimantan, Indonesia. Malaria prevalence ranged from 0.9% to 2.7% in Dayak villages and from 1% to 20% in the transmigration settlements. Plasmodium falciparum accounted for 67% of the cases among Dayaks but P. vivax was dominant among transmigrants, accounting for more than 72% of the infections. Chloroquine sensitivity/resistance was assessed by 28-day in vivo testing of uncomplicated malaria infections and measurement of chloroquine blood levels in cases where parasitemias reappeared within the 28-day test period. Resistance was based on the appearance of asexual parasites against chloroquine plus desethylchloroquine levels exceeding the minimally effective whole blood concentrations proposed for sensitive parasite strains (P. vivax, 100 ng/ml; P. falciparum, 200 ng/ml). All parasitemias cleared initially within four days of beginning supervised chloroquine therapy (25 mg base/kg over a 48-hr period), but asexual parasites reappeared within 28 days in 27 of 52 P. vivax and three of 12 P. falciparum cases. Chloroquine blood levels at the time of recurrent parasitemias revealed resistance in 12 of the 27 P. vivax cases and in one of the three P. falciparum cases. Genotypes of nine of the 12 recurrent P. vivax isolates matched with their primary isolates and ruled out reinfection. These findings establish the presence of chloroquine-resistant P. vivax on the island of Borneo. The pattern of malaria and the high frequency of chloroquine resistance by P. vivax at the West Kalimantan location may relate to demographic, ecologic, agricultural, and socioeconomic changes associated with transmigration. C1 USN, Med Res Unit 2, Jakarta, Indonesia. Natl Inst Hlth Res, Jakarta, Indonesia. Prov Dept Hlth, Pontianak, W Kalimantan, Indonesia. Dist Hlth Off, Ketapang, W Kalimantan, Indonesia. Univ Toronto, Dept Med, Toronto Hosp, Toronto, ON M5G 2C4, Canada. USN, Med Res Inst, Rockville, MD 20852 USA. RP Fryauff, DJ (reprint author), USN, Med Res Unit 2, Jakarta, Indonesia. NR 29 TC 60 Z9 61 U1 0 U2 0 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 USA SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD OCT PY 1998 VL 59 IS 4 BP 513 EP 518 PG 6 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA 129QD UT WOS:000076473700006 PM 9790420 ER PT J AU Wardlaw, WP AF Wardlaw, WP TI Partial invertibility is impossible SO AMERICAN MATHEMATICAL MONTHLY LA English DT Letter C1 USN Acad, Annapolis, MD 21402 USA. RP Wardlaw, WP (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MATHEMATICAL ASSOC AMER PI WASHINGTON PA 1529 18TH STREET NW, WASHINGTON, DC 20036 USA SN 0002-9890 J9 AM MATH MON JI Am. Math. Mon. PD OCT PY 1998 VL 105 IS 8 BP 773 EP 773 DI 10.2307/2589006 PG 1 WC Mathematics SC Mathematics GA 125KV UT WOS:000076237500015 ER PT J AU Pazirandeh, M Wells, BM Ryan, RL AF Pazirandeh, M Wells, BM Ryan, RL TI Development of bacterium-based heavy metal biosorbents: Enhanced uptake of cadmium and mercury by Escherichia coli expressing a metal binding motif SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID NEUROSPORA-CRASSA METALLOTHIONEIN; ION-EXCHANGE RESINS; PROTEINS; GENE; REMOVAL; DESIGN; SITES; REDUCTION AB A gene coding for a de novo peptide sequence containing a metal binding motif was chemically synthesized and expressed in Escherichia coli as a fusion with the maltose binding protein. Bacterial cells expressing the metal binding peptide fusion demonstrated enhanced binding of Cd2+ and Hg2+ compared to bacterial cells lacking the metal binding peptide. The potential use of genetically engineered bacteria as biosorbents for the removal of heavy metals from wastewaters is discussed. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Pazirandeh, M (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. EM mpp@cbmse.nrl.navy.mil NR 30 TC 75 Z9 83 U1 0 U2 9 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD OCT PY 1998 VL 64 IS 10 BP 4068 EP 4072 PG 5 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 126LP UT WOS:000076295100080 PM 9758845 ER PT J AU Willumsen, PA Karlson, U Pritchard, PH AF Willumsen, PA Karlson, U Pritchard, PH TI Response of fluoranthene-degrading bacteria to surfactants SO APPLIED MICROBIOLOGY AND BIOTECHNOLOGY LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; NONIONIC SURFACTANTS; BIODEGRADATION; SOLUBILIZATION; SOIL; MINERALIZATION; PHENANTHRENE; BIOAVAILABILITY; DEGRADATION; MEMBRANES AB A prerequisite for surfactant-enhanced biodegradation is that the microorganisms survive, take up substrate and degrade it in the presence of the surfactant. Two Mycobacterium and two Sphingomonas strains, degrading fluoranthene, were investigated for their sensitivity towards non-ionic chemical surfactants. The effect of Triton X-100 and Tween 80 above their critical micelle concentration on mineralization of [(14)C]-glucose and [(14)C]-fluoranthene was measured in shaker cultures. Tween 80 had no toxic effect on any of the tested strains. The surfactant inhibited fluoranthene mineralization by the hydrophobic Mycobacterium spp. slightly, but more than doubled that by the two less hydrophobic Sphingomonas strains. Triton X-100 inhibited fluoranthene mineralization by all strains, yet this was more pronounced for the Sphingomonas spp. Both surfactants caused cell wall permeabilization, as shown by transient colouring of surfactant-containing media. Inhibition of glucose mineralization, indicating non-specific toxic effects of Triton X-100, was observed only for the Sphingomonas strains and the toxicity was caused by micelle-to-cell interactions. These strains, however, appeared to recover from initial Triton X-100 toxicity within 50-500 h of exposure. The ratio of surfactant concentration to initial cell density was found to determine critically the bacterial response to surfactants. For both Sphingomonas and Mycobacterium strains, this work indicates that fluoranthene solubilized in surfactant micelles is only partially available for mineralization by the bacteria tested. However, our results suggest that optimal conditions for polycyclic aromatic hydrocarbon mineralization can be developed by selection of the proper surfactant, bacterial strains, cell density and incubation conditions. C1 Natl Environm Res Inst, Dept Marine Ecol & Microbiol, Roskilde, Denmark. USN, Res Lab, Environm Qual Sci Sect, Washington, DC 20375 USA. RP Willumsen, PA (reprint author), Natl Environm Res Inst, Dept Marine Ecol & Microbiol, Roskilde, Denmark. EM paw@dmu.dk NR 34 TC 59 Z9 59 U1 0 U2 10 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0175-7598 J9 APPL MICROBIOL BIOT JI Appl. Microbiol. Biotechnol. PD OCT PY 1998 VL 50 IS 4 BP 475 EP 483 PG 9 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 137LG UT WOS:000076915800012 ER PT J AU Wynne, KJ Ho, T Johnston, EE Myers, SA AF Wynne, KJ Ho, T Johnston, EE Myers, SA TI Surface science and stability of networks prepared from hydroxy-terminated polydimethylsiloxane and methyltriethoxysilane SO APPLIED ORGANOMETALLIC CHEMISTRY LA English DT Article DE siloxane network; contact angle; sol-gel reaction; polydimethylsiloxane AB Polydimethylsiloxane (PDMS) hybrid networks have been prepared by the reaction of PDMS(OH)(2), average molecular weight 26 x 10(3), 43.6 x 10(3) and 58 x 10(3), and methyltriethoxysilane (MeTEOS, 10-60 wt%) using a dibutyltin dilaurate or dibutyltin diacetate catalyst. By hydrolysis and homo- and cocondensation, MeTEOS forms a siliceous domain (MeSD) and acts as a crosslinker for the PDMS domain, Kinetic studies showed that high MeTEOS and catalyst concentrations and reduction of free surface area favor fast gelation and efficiency in converting MeTEOS to the MeSD, Under the water-sparse conditions utilized, cure was slow and substantial evaporative loss of MeTEOS occurred. (C) 1998 John Wiley & Sons, Ltd. C1 USN, Res Lab, Mat Chem Branch, Washington, DC 20375 USA. Off Naval Res, Phys Sci S&T Div, Arlington, VA 22217 USA. Virginia Polytech Inst & State Univ, Dept Chem, Blacksburg, VA 24061 USA. USN, Air Warfare Ctr, Weap Div, Chem & Mat Branch, China Lake, CA 93555 USA. RP Wynne, KJ (reprint author), USN, Res Lab, Mat Chem Branch, Code 6120, Washington, DC 20375 USA. NR 14 TC 15 Z9 15 U1 4 U2 18 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0268-2605 J9 APPL ORGANOMET CHEM JI Appl. Organomet. Chem. PD OCT-NOV PY 1998 VL 12 IS 10-11 BP 763 EP 770 DI 10.1002/(SICI)1099-0739(199810/11)12:10/11<763::AID-AOC784>3.0.CO;2-C PG 8 WC Chemistry, Applied; Chemistry, Inorganic & Nuclear SC Chemistry GA 128LX UT WOS:000076409200014 ER PT J AU Lazio, TJW Cordes, JM AF Lazio, TJW Cordes, JM TI Hyperstrong radio-wave scattering in the galactic center. II. A likelihood analysis of free electrons in the galactic center SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxy : center; ISM : general; radio continuum : ISM; scattering ID ANISOTROPIC MAGNETOGASDYNAMIC TURBULENCE; LOCAL INTERSTELLAR-MEDIUM; SAGITTARIUS A-ASTERISK; SOURCE SGR-A; DENSITY-FLUCTUATIONS; MAGNETOHYDRODYNAMIC TURBULENCE; ALFVENIC TURBULENCE; INNER SCALE; PLASMA; PLANE AB The scattering diameters of Sgr A* and several nearby OH masers (approximate to 1 " at 1 GHz) indicate that a region of enhanced scattering is along the line of sight to the Galactic center. We combine radio-wave scattering data and free-free emission and absorption measurements in a likelihood analysis that constrains the following parameters of the GC scattering region: The GC-scattering region separation, A,,; the angular extent of the region, psi(l), and psi(b); the outer scale on which density fluctuations occur, l(o); and the gas temperature, T(e). The maximum likelihood estimates of these parameters are Delta(GC) = 133+(+200)(-80) pc, 0.degrees 5 less than or equal to psi(l) less than or similar to 1 degrees, and (l(o)/1 pc)(2/3)T(e)(-1/2) = 10(-7+/-0.8). The parameter psi(b) was not well constrained, and we adopt psi(b) = 0.degrees 5. The close correspondence between Delta(GC) and psi(l)D(GC) suggests that the scattering region encloses the GC. As host media for the scattering, we consider the photoionized surface layers of molecular clouds and the interfaces between molecular clouds and the 10(7) K ambient gas. We are unable to make an unambiguous determination, but we favor the interface model in which the scattering medium is hot (T(e) similar to 10(6) K) and dense (n(e) similar to 10 cm(-3)). The GC scattering region produces a 1 GHz scattering diameter for an extragalactic source of 90 ", if the region is a single screen, or 180 ", if the region wraps around the GC, as appears probable. We modify the Taylor-Cordes model for the Galactic distribution of free electrons in order to include an explicit GC component. We predict that pulsars seen through this region will have a dispersion measure of approximately 2000 pc cm(-3), of which approximately 1500 pc cm(-3) arises from the GC component itself. We stress the uniqueness of the GC scattering region, probably resulting from the high-pressure environment in the GC. C1 USN, Res Lab, Washington, DC 20375 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Cornell Univ, Natl Astron & Ionosphere Ctr, Ithaca, NY 14853 USA. RP Lazio, TJW (reprint author), USN, Res Lab, Code 7210, Washington, DC 20375 USA. EM lazio@rsd.nrl.navy.mil; cordes@spacenet.tn.cornell.edu NR 74 TC 75 Z9 75 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1998 VL 505 IS 2 BP 715 EP 731 DI 10.1086/306174 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500019 ER PT J AU Esin, AA Narayan, R Cui, W Grove, JE Zhang, SN AF Esin, AA Narayan, R Cui, W Grove, JE Zhang, SN TI Spectral transitions in Cygnus X-1 and other black hole X-ray binaries SO ASTROPHYSICAL JOURNAL LA English DT Review DE accretion, accretion disks; black hole physics; stars : individual (Cygnus X-1, GRO J0422+32, GRO J1719-24); X-rays : stars ID ADVECTION-DOMINATED ACCRETION; ACTIVE GALACTIC NUCLEI; 226868 = CYGNUS-X-1; NOVA-MUSCAE 1991; HDE 226868; GRO J0422+32; DISK MODEL; OPTICAL COUNTERPART; SPHERICAL ACCRETION; INTERMEDIATE STATE AB We show that the model proposed by Esin, McClintock, & Narayan for the low state, intermediate stale, and high state of the black hole soft X-ray transient, Nova Muscae 1991, is consistent with the spectral evolution of the black hole X-ray binary, Cyg X-1, during the hard-to-soft slate transition observed in 1996. We also apply the model to the outbursts of two other black hole X-ray transients, GRO J0422 + 32 and GRO J1719 - 24. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. USN, Res Lab, Washington, DC 20375 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Esin, AA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 120 TC 205 Z9 208 U1 0 U2 0 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 OCT 1 PY 1998 VL 505 IS 2 BP 854 EP 868 DI 10.1086/306186 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500029 ER PT J AU Feldman, U Schuhle, U Widing, KG Laming, JM AF Feldman, U Schuhle, U Widing, KG Laming, JM TI Coronal composition above the solar equator and the north pole as determined from spectra acquired by the SUMER instrument on Soho SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : abundances; Sun : corona ID WAVE COLLISION STRENGTHS; ATOMIC DATA; ELEMENTAL ABUNDANCES; OSCILLATOR-STRENGTHS; WIND; IONS; ATMOSPHERE; DENSITY; HOLE; RECOMBINATION AB Using spectra obtained by the SUMER instrument on the Solar and Heliospheric Observatory (SONO) we have determined the composition of the bulk of the coronal plasma in the vicinity of the solar surface over a polar coronal hole and an equatorial region. Our measurements show that although low first ionization potential (FIP) elements are enriched by about a factor of 4 in the corona above the quiet equatorial region, little or no enrichment exists above the north polar coronal hole. These observations are in good agreement with the Ulysses in situ observations in both fast speed and slow speed winds. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. SFA Inc, Largo, MD 20774 USA. RP Feldman, U (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Mail Code 7608,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 42 TC 103 Z9 103 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1998 VL 505 IS 2 BP 999 EP 1006 DI 10.1086/306195 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500042 ER PT J AU Koffman, RL Berg, JS Moore, J AF Koffman, RL Berg, JS Moore, J TI Compulsive sexual behaviors - Difficult aeromedical disposition SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID PARAPHILIAS; ADDICTIONS; MEN; DISORDERS AB Axis I psychiatric disorders generally are considered incompatible with both the issuance and subsequent maintenance of aeromedical clearance certificates. Little doubt exists as to the impact that conditions such as anxiety disorders, mood disorders, or substance-related disorders have on the conduct of safe flight. Nevertheless, different compulsive sexual behaviors (CSBs), which now are thought to share similar origins and associated comorbidity, can similarly affect impulse control, judgment, concentration, and insight. Yet, these conditions frequently are handled administratively (if not legally). Moreover, in practice (CSBs fall within a spectrum of behaviors from "normative" nonparaphilic sexuality to more deviant paraphilic behavior. Through the presentation of five selected cases seen at the Naval Operational Medicine Institute, this article explores examiner difficulty in establishing a diagnosis, discusses models useful in understanding the origins of these disorders, and highlights critical elements in establishing aeromedical disposition. The authors conclude that CSBs may be associated with anxiety, dysphoria, a pattern of increased risk taking, a high threshold for arousal, and poor judgment, which may impact the safety of flight. A comprehensive psychiatric evaluation is essential in determining aeromedical disposition, and consideration should be given to reviewing these cases from a medical perspective prior to any administrative disposition. C1 USN, Operat Med Inst, Naval Air Stn, Dept Psychiat, Pensacola, FL USA. RP Koffman, RL (reprint author), USS Carl Vinson, FPO, AP 96629 USA. NR 19 TC 0 Z9 0 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 OCT PY 1998 VL 69 IS 10 BP 1001 EP 1006 PG 6 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 123KY UT WOS:000076125400014 PM 9773905 ER PT J AU Baselt, DR Lee, GU Natesan, M Metzger, SW Sheehan, PE Colton, RJ AF Baselt, DR Lee, GU Natesan, M Metzger, SW Sheehan, PE Colton, RJ TI A biosensor based on magnetoresistance technology SO BIOSENSORS & BIOELECTRONICS LA English DT Article DE intermolecular forces; giant magnetoresistance; magnetic beads ID ATOMIC-FORCE MICROSCOPE; GIANT MAGNETORESISTANCE; ADHESION; DNA; RECOGNITION; EVENTS AB We are developing a biosensor that will measure, at the level of single molecules, the forces that bind DNA-DNA, antibody-antigen, or ligand-receptor pairs together. The Bead Array Counter (BARC) will use these interaction forces to hold magnetic microbeads to a solid substrate. Microfabricated magnetoresistive transducers on the substrate will indicate whether or not the beads are removed when pulled by magnetic forces. By adapting magnetoresistive computer memory technology, it may be possible to fabricate millions of transducers on a chip and detect or screen thousands of analytes. The multi-analyte capability of this portable sensor would be ideal for on-site testing, while the potential to directly gauge intermolecular interaction strengths suggests drug discovery applications. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Geocenters Inc, Lanham, MD 20705 USA. RP Baselt, DR (reprint author), USN, Res Lab, Code 6177, Washington, DC 20375 USA. RI Sheehan, Paul/B-4793-2010; Lee, Gil/P-8696-2016 OI Sheehan, Paul/0000-0003-2668-4124; Lee, Gil/0000-0002-7949-5848 NR 25 TC 526 Z9 534 U1 7 U2 94 PU ELSEVIER ADVANCED TECHNOLOGY PI OXFORD PA OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0956-5663 J9 BIOSENS BIOELECTRON JI Biosens. Bioelectron. PD OCT 1 PY 1998 VL 13 IS 7-8 BP 731 EP 739 DI 10.1016/S0956-5663(98)00037-2 PG 9 WC Biophysics; Biotechnology & Applied Microbiology; Chemistry, Analytical; Electrochemistry; Nanoscience & Nanotechnology SC Biophysics; Biotechnology & Applied Microbiology; Chemistry; Electrochemistry; Science & Technology - Other Topics GA 136CT UT WOS:000076841100001 PM 9828367 ER PT J AU Marshall, J Dobson, F Moore, K Rhines, P Visbeck, M d'Asaro, E Bumke, K Chang, S Davis, R Fischer, K Garwood, R Guest, P Harcourt, R Herbaut, C Holt, T Lazier, J Legg, S McWilliams, J Pickart, R Prater, M Renfrew, I Schott, F Send, U Smethie, W AF Marshall, J Dobson, F Moore, K Rhines, P Visbeck, M d'Asaro, E Bumke, K Chang, S Davis, R Fischer, K Garwood, R Guest, P Harcourt, R Herbaut, C Holt, T Lazier, J Legg, S McWilliams, J Pickart, R Prater, M Renfrew, I Schott, F Send, U Smethie, W CA Lab Sea Grp TI The Labrador Sea deep convection experiment SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID NORTH-ATLANTIC; OCEAN; VARIABILITY; TEMPERATURES; WINTER AB In the autumn of 1996 the field component of an experiment designed to observe water mass transformation began in the Labrador Sea. Intense observations of ocean convection were taken in the following two winters. The purpose of the experiment was, by a combination of meteorological and oceanographic field observations, laboratory studies, theory, and modeling, to improve understanding of the convective process in the ocean and its representation in models. The dataset that has been gathered far exceeds previous efforts to observe the convective process anywhere in the ocean, both in its scope and range of techniques deployed. Combined with a comprehensive set of meteorological and air-sea flux measurements, it is giving unprecedented insights into the dynamics and thermodynamics of a closely coupled, semienclosed system known to have direct influence on the processes that control global climate. C1 MIT, Dept Earth Atmospher & Planetary Studies, Cambridge, MA 02139 USA. Bedford Inst Oceanog, Dartmouth, NS, Canada. Univ Toronto, Toronto, ON, Canada. Univ Washington, Seattle, WA 98195 USA. Lamont Doherty Earth Observ, Palisades, NY 10964 USA. Univ Washington, Dept Meteorol, Seattle, WA 98195 USA. Univ Kiel, Inst Meereskunde, Dept Meteorol, D-2300 Kiel, Germany. USN, Res Lab, Monterey, CA USA. Scripps Inst Oceanog, San Diego, CA USA. Environm Res Inst Michigan, Ann Arbor, MI 48107 USA. USN, Postgrad Sch, Monterey, CA USA. Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. Univ Calif Los Angeles, Los Angeles, CA USA. Univ Rhode Isl, Kingston, RI 02881 USA. RP Marshall, J (reprint author), MIT, Dept Earth Atmospher & Planetary Studies, Bldg 54-1256, Cambridge, MA 02139 USA. EM marshall@gulf.mit.edu RI Renfrew, Ian/E-4057-2010; Legg, Sonya/E-5995-2010; Visbeck, Martin/G-2461-2011; Visbeck, Martin/B-6541-2016; OI Renfrew, Ian/0000-0001-9379-8215; Visbeck, Martin/0000-0002-0844-834X; Visbeck, Martin/0000-0002-0844-834X; Davis, Russ/0000-0003-1903-6313 NR 30 TC 130 Z9 130 U1 2 U2 18 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 OCT PY 1998 VL 79 IS 10 BP 2033 EP 2058 PG 26 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 132PK UT WOS:000076638600002 ER PT J AU Hannan, PJ AF Hannan, PJ TI Chemically speaking SO CHEMTECH LA English DT Editorial Material C1 USN, Res Labs, Washington, DC 20375 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 0009-2703 J9 CHEMTECH JI Chemtech PD OCT PY 1998 VL 28 IS 10 BP IBC EP IBC PG 1 WC Chemistry, Applied SC Chemistry GA 128FM UT WOS:000076395100015 ER PT J AU Belgrader, P Benett, W Hadley, D Long, G Mariella, R Milanovich, F Nasarabadi, S Nelson, W Richards, J Stratton, P AF Belgrader, P Benett, W Hadley, D Long, G Mariella, R Milanovich, F Nasarabadi, S Nelson, W Richards, J Stratton, P TI Rapid pathogen detection using a microchip PCR array Instrument SO CLINICAL CHEMISTRY LA English DT Article ID POLYMERASE CHAIN-REACTION; INFECTIOUS-DISEASES; DNA-POLYMERASE; AMPLIFICATION; EMERGENCE AB An array of PCR microchips for rapid, parallel testing of samples for pathogenic microbes is described. The instrument, called the Advanced Nucleic Acid Analyzer (ANAA), utilizes 10 silicon reaction chambers with thin-film resistive heaters and solid-state optics. Features of the system include efficient heating and realtime monitoring, low power requirements for battery operation, and no moving parts for reliability and ruggedness. We analyzed cultures of Erwinia herbicola vegetative cells, Bacillus subtilis spores, and MS2 virions, which simulated pathogenic microbes such as Yersinia pestis, Bacillus anthracis spores, and Venezuelan equine encephalitis, respectively. Detection of microbes was achieved in as little as 16 min with detection limits of 10(5)-10(7) organisms/L (10(2)-10(4) organisms/mL). C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. USN, Med Res Inst, Bethesda, MD 20814 USA. RP Belgrader, P (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 808,L-452, Livermore, CA 94551 USA. EM belgrader1@llnl.gov NR 19 TC 110 Z9 116 U1 0 U2 5 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 OCT PY 1998 VL 44 IS 10 BP 2191 EP 2194 PG 4 WC Medical Laboratory Technology SC Medical Laboratory Technology GA 124RT UT WOS:000076196200020 PM 9761255 ER PT J AU Bounlu, K Insisiengmay, S Vanthanouvong, K Widjaja, SS Iinuma, K Matsubayashi, K Laras, K Putri, MP Endy, TP Vaughn, DW Raengsakulrach, B Hyams, KC Hayden, M Scheffel, C Corwin, AL AF Bounlu, K Insisiengmay, S Vanthanouvong, K Widjaja, SS Iinuma, K Matsubayashi, K Laras, K Putri, MP Endy, TP Vaughn, DW Raengsakulrach, B Hyams, KC Hayden, M Scheffel, C Corwin, AL TI Acute jaundice in Vientiane, Lao People's Democratic Republic SO CLINICAL INFECTIOUS DISEASES LA English DT Article ID HEPATITIS-G VIRUS; WATERBORNE OUTBREAK; VIRAL-HEPATITIS; HIGH PREVALENCE; TRANSMISSION; DIAGNOSIS; PITFALLS; TROPICS; VIETNAM; VIREMIA AB Analysis of serum samples from patients with acute jaundice by means of enzyme-linked immunosorbent assay and polymerase chain reaction testing provided the first profile of this condition in Vientiane, Lao PDR, in 1995 and 1996, In a case-control, hospital-based study, evidence of acute infections due to hepatitis A and B viruses was found in 14% and 10% of cases, respectively. Hepatitis E virus, however, did not appear to contribute to clinically recognized acute jaundice. Similarly, antibody to hepatitis C virus was recognized in almost equal proportions of cases (8%) and controls (6%), thus representing probable background infections. The detection of hepatitis G virus marks the first report of this virus in Lao PDR. The large proportion (21%) of new leptospiral infections in cases without acute hepatitis A or B was notable. This finding suggests significant regional underreporting of leptospirosis as a cause of acute jaundice. The limited laboratory diagnostic capabilities for confirming a differential diagnosis of leptospirosis contribute to the lack of attention paid to this important health problem. C1 USN, Med Res Unit, Jakarta, Indonesia. Dainabot Co, Chiba, Japan. Armed Forces Res Inst Med Sci, Bangkok 10400, Thailand. USN, Med Res Inst, Bethesda, MD USA. Abbott Labs, Abbott Pk, IL 60064 USA. RP Corwin, AL (reprint author), NAMRU 2, Box 3,Unit 8132, APO, AP 96520 USA. NR 19 TC 12 Z9 14 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 1058-4838 J9 CLIN INFECT DIS JI Clin. Infect. Dis. PD OCT PY 1998 VL 27 IS 4 BP 717 EP 721 DI 10.1086/514948 PG 5 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 129ZF UT WOS:000076493400011 PM 9798023 ER PT J AU Montgomery, CJ Khokhlov, AM Oran, ES AF Montgomery, CJ Khokhlov, AM Oran, ES TI The effect of mixing irregularities on mixed-region critical length for deflagration-to-detonation transition SO COMBUSTION AND FLAME LA English DT Article ID GRID-GENERATED TURBULENCE; TEMPERATURE-FLUCTUATIONS; JET INITIATION; NONUNIFORMITIES; MIXTURES; SCALAR; DECAY AB Deflagration-to-detonation transition (DDT) may occur through the Zel'dovich or shock wave amplification by coherent energy release (SWACER) gradient mechanism when spatial nonuniformities in temperature and composition are formed through turbulent mixing of reaction products with unburned gas. If the gradient region is large enough, a spontaneous reaction wave will form and strengthen into a detonation that may propagate into the unburned mixture. Such gradient regions formed by turbulent mixing are likely to be highly irregular, containing disturbances with a wide range of magnitudes and length scales. One-dimensional calculations in which a sinusoidal disturbance is superimposed on a linear gradient are used to examine the effect of disturbance amplitude and frequency on the size of a mixed region necessary for DDT. The results suggest that disturbances caused by turbulent mixing may increase the critical length by more than order of magnitude as compared to an undisturbed linear gradient. Disturbances of intermediate frequency increase the critical length more than those of very low or very high frequency. Large-amplitude disturbances increase the critical length by effectively dividing the gradient into subregions. (C) 1998 by The Combustion Institute. C1 USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. RP Oran, ES (reprint author), USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. NR 30 TC 17 Z9 18 U1 0 U2 8 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD OCT PY 1998 VL 115 IS 1-2 BP 38 EP 50 DI 10.1016/S0010-2180(97)00360-X PG 13 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA ZU524 UT WOS:000074206700003 ER PT J AU Halstead, SB AF Halstead, SB TI Of cytokines and things SO CURRENT OPINION IN INFECTIOUS DISEASES LA English DT Editorial Material ID DENGUE C1 Off Naval Res, Arlington, VA 22217 USA. RP Halstead, SB (reprint author), Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0951-7375 J9 CURR OPIN INFECT DIS JI Curr. Opin. Infect. Dis. PD OCT PY 1998 VL 11 IS 5 BP 515 EP 518 PG 4 WC Infectious Diseases SC Infectious Diseases GA 136FT UT WOS:000076848400001 ER PT J AU Carucci, DJ Gardner, MJ Tettelin, H Cummings, LM Smith, HO Adams, MD Venter, JC Hoffman, SL AF Carucci, DJ Gardner, MJ Tettelin, H Cummings, LM Smith, HO Adams, MD Venter, JC Hoffman, SL TI Sequencing the genome of Plasmodium falciparum SO CURRENT OPINION IN INFECTIOUS DISEASES LA English DT Review ID GENE-EXPRESSION; PROJECT; MALARIA AB Advances in microbial genomic sequencing have the potential to revolutionize the control of infectious diseases. Recently, a consortium of researchers and funding agencies from the United States and Great Britain have embarked on a project to sequence the genome from Plasmodium falciparum, the most important cause of human malaria. The Malaria Genome Sequencing Project has reached an important milestone with the completion of the entire DNA sequence and annotation of chromosome 2, a 950 kilobase chromosome of Plasmodium falciparum, This review article will provide an overview of the malaria genome sequencing project, highlight progress in the field of microbial sequencing, and suggest new directions for future malaria research. Curr Opin Infect Dis 11:531-534. (C) 1998 Lippincott Williams & Wilkins. C1 USN, Med Res Inst, Malaria Program, Bethesda, MD 20889 USA. RP Carucci, DJ (reprint author), USN, Med Res Inst, Malaria Program, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. EM caruccid@nmripo.nmri.mml.navy.mil NR 15 TC 4 Z9 4 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0951-7375 J9 CURR OPIN INFECT DIS JI Curr. Opin. Infect. Dis. PD OCT PY 1998 VL 11 IS 5 BP 531 EP 534 PG 4 WC Infectious Diseases SC Infectious Diseases GA 136FT UT WOS:000076848400003 PM 17033418 ER PT J AU Steeds, JW Gilmore, A Wilson, JA Butler, JE AF Steeds, JW Gilmore, A Wilson, JA Butler, JE TI On the nature of extended defects in CVD diamond and the origin of compressive stresses SO DIAMOND AND RELATED MATERIALS LA English DT Article DE transmission electron microscopy; CVD diamond; defects; stress ID MOLECULAR-BEAM EPITAXY; STACKING-FAULTS; RAMAN-SPECTROSCOPY; FILMS; GROWTH; TEM; MICROSTRUCTURE; DEFORMATION; THICKNESS; CONTRAST AB Diffraction contrast transmission electron microscopy has been used in a detailed investigation of the nature of defects in thick square-faceted CVD diamond films. It is concluded that each crystallite progresses from octahedral growth with {111} facets to truncated octahedra before reaching the final form with large square facets. Open-faced tetrahedral defects are formed on the {111} faces of the octahedra with faults or very thin twins on the three {111} planes inclined to each facet growth surface. By micro-Raman experiments on individual grains of electron transparent regions and electron-energy-loss spectroscopy, it was shown that the defective regions are associated with the incorporation of non-diamond carbon and a model is proposed, based on this information, to account for the very high compressive stresses that have been found in these diamond films. Published by Elsevier Science S.A. All rights reserved. C1 Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. USN, Res Lab, Washington, DC 20375 USA. RP Steeds, JW (reprint author), Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 36 TC 16 Z9 16 U1 0 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD OCT PY 1998 VL 7 IS 10 BP 1437 EP 1450 DI 10.1016/S0925-9635(98)00212-X PG 14 WC Materials Science, Multidisciplinary SC Materials Science GA 133TM UT WOS:000076701900003 ER PT J AU Yarina, KL Dandy, DS Jensen, E Butler, JE AF Yarina, KL Dandy, DS Jensen, E Butler, JE TI Growth of diamond films using an enclosed methyl-acetylene and propadiene combustion flame SO DIAMOND AND RELATED MATERIALS LA English DT Article DE combustion synthesis; deposition; diamond films; morphology ID CHEMICAL-VAPOR-DEPOSITION; OXYGEN FLAMES; PRESSURE; TORCH; NUCLEATION; CVD AB Diamond growth in low-pressure combustion flames was studied using a safer, more economical substitute for acetylene: a mixture of methylacetylene, propadiene, and liquefied petroleum (MAPP gas). A burner-stabilized, low pressure, flat, premixed flame was used to deposit continuous, uniform thickness diamond films on a heated molybdenum substrate. This work identities the dependence of film growth rate and quality on the fuel-to-oxygen ratio and the burner-substrate separation distance at two different reactor pressures of 70 and 250 Torr. A single substrate temperature of 800 degrees C was used to consistently produce well-faceted films. For the MAPP/O(2), premixed flame, it was determined that the optimal fuel-to-oxygen ratios for diamond growth are 0.53 at 70 Torr and 0.51 at 250 Torr. Typical growth rates at these conditions were on the order of 1 mu m h(-1). However, growth rate and quality are very sensitive to the fuel-to-oxygen ratio, falling off rapidly in either direction from the optimal value. Increasing the ratio enhances secondary nucleation, and eventually results in graphitic and amorphous material. The growth rate is also very sensitive to the burner-substrate separation distance due to tight coupling between the transport and chemical kinetic time scales in the combustion reactor. (C) 1998 Published by Elsevier Science S.A. All rights reserved. C1 Colorado State Univ, Dept Chem Engn, Ft Collins, CO 80523 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Dandy, DS (reprint author), Colorado State Univ, Dept Chem Engn, Ft Collins, CO 80523 USA. EM dandy@engr.colostate.edu RI Butler, James/B-7965-2008; Dandy, David/G-6984-2012 OI Butler, James/0000-0002-4794-7176; Dandy, David/0000-0003-3254-0717 NR 38 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD OCT PY 1998 VL 7 IS 10 BP 1491 EP 1502 DI 10.1016/S0925-9635(98)00221-0 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 133TM UT WOS:000076701900010 ER PT J AU Nuti, M Serafini, DA Bassetti, D Ghionni, A Russino, F Rombola, P Macri, G Lillini, E AF Nuti, M Serafini, DA Bassetti, D Ghionni, A Russino, F Rombola, P Macri, G Lillini, E TI Ehrlichia infection in Italy SO EMERGING INFECTIOUS DISEASES LA English DT Article ID HUMAN GRANULOCYTIC EHRLICHIOSIS; LYME BORRELIOSIS; ANTIBODIES; DISEASE; EUROPE AB Immunoglobulin M seroconversion to Ehrlichia chaffeensis was documented in U.S. citizens bitten by ticks in Sardinia. Seven cases of suspected ehrlichiosis in local residents were not confirmed by laboratory tests. In Alpine areas antibodies to E. phagocytophila were detected in persons at high risk, i.e., foresters (8.6%) and hunters (5.5%), and in controls (1.5%). Of 153 persons bitten by ticks, only one was Ehrlichia antibody-positive after 6 months. C1 Ist Zooprofilatt, I-00178 Rome, Italy. Univ Rome 1, I-00185 Rome, Italy. USN, Med Serv, Colorado Springs, CO USA. Dept Publ Hlth, Trento, Italy. Pieve Cadore Hosp, Belluno, Italy. Multizone Prevent Serv, Belluno, Italy. RP Lillini, E (reprint author), Ist Zooprofilatt, Via Appia Nuova 1411, I-00178 Rome, Italy. NR 11 TC 33 Z9 37 U1 0 U2 1 PU CENTER DISEASE CONTROL PI ATLANTA PA ATLANTA, GA 30333 USA SN 1080-6040 J9 EMERG INFECT DIS JI Emerg. Infect. Dis PD OCT-DEC PY 1998 VL 4 IS 4 BP 663 EP 665 PG 3 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 148BN UT WOS:000077532500020 PM 9866746 ER PT J AU Malakooti, MA Biomndo, K Shanks, GD AF Malakooti, MA Biomndo, K Shanks, GD TI Reemergence of epidemic malaria in the highlands of western Kenya SO EMERGING INFECTIOUS DISEASES LA English DT Article AB Hospital records (1990-1997) of a tea company in the Kericho district, western Kenya, showed malaria epidemics almost annually from May to July, with an annual attack rate of 50%, 857 hospitalizations per 100,000 per year, and 42 deaths per 100,000 per year; 32% of deaths in hospitalized patients were caused by malaria. A questionnaire survey (June 1997) of 244 patients hospitalized for malaria showed that only 8% had traveled to an area with known malaria transmission 30 days before diagnosis. The increasing malaria incidence may be due to drug resistance. C1 USA, Med Res Unit, Nairobi, Kenya. Uniformed Serv Univ Hlth Sci, Bethesda, MD 20814 USA. Brooke Bond Cent Hosp, Kericho, Kenya. RP Malakooti, MA (reprint author), USN, Environm & Prevent Med Unit 2, Dept Epidemiol, MTM&H, 1887 Powhatan St, Norfolk, VA 23511 USA. RI Shanks, George Dennis/F-4056-2014 OI Shanks, George Dennis/0000-0001-5763-8660 NR 12 TC 113 Z9 115 U1 0 U2 1 PU CENTER DISEASE CONTROL PI ATLANTA PA ATLANTA, GA 30333 USA SN 1080-6040 J9 EMERG INFECT DIS JI Emerg. Infect. Dis PD OCT-DEC PY 1998 VL 4 IS 4 BP 671 EP 676 PG 6 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 148BN UT WOS:000077532500022 PM 9866748 ER PT J AU Wallace, MR AF Wallace, MR TI Paratyphoid fever SO EMERGING INFECTIOUS DISEASES LA English DT Letter RP Wallace, MR (reprint author), USN, Med Ctr, San Diego, CA 92152 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU CENTER DISEASE CONTROL PI ATLANTA PA ATLANTA, GA 30333 USA SN 1080-6040 J9 EMERG INFECT DIS JI Emerg. Infect. Dis PD OCT-DEC PY 1998 VL 4 IS 4 BP 707 EP 707 PG 1 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 148BN UT WOS:000077532500033 ER PT J AU Knoke, JD Gray, GC AF Knoke, JD Gray, GC TI Hospitalizations after the Gulf War - Reply to K.M. Leisure et al. SO EMERGING INFECTIOUS DISEASES LA English DT Letter C1 USN, Hlth Res Ctr, San Diego, CA 92152 USA. RP Knoke, JD (reprint author), USN, Hlth Res Ctr, San Diego, CA 92152 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU CENTER DISEASE CONTROL PI ATLANTA PA ATLANTA, GA 30333 USA SN 1080-6040 J9 EMERG INFECT DIS JI Emerg. Infect. Dis PD OCT-DEC PY 1998 VL 4 IS 4 BP 709 EP 709 PG 1 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 148BN UT WOS:000077532500035 ER PT J AU Dwyer, S AF Dwyer, S TI Sex, preference, and family: Essays on law and nature. SO ETHICS LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Dwyer, S (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0014-1704 J9 ETHICS JI Ethics PD OCT PY 1998 VL 109 IS 1 BP 184 EP 187 DI 10.1086/233885 PG 4 WC Ethics; Philosophy SC Social Sciences - Other Topics; Philosophy GA 133EE UT WOS:000076672800016 ER PT J AU Ndubizu, CC Ananth, R Tatem, PA Motevalli, V AF Ndubizu, CC Ananth, R Tatem, PA Motevalli, V TI On water mist fire suppression mechanisms in a gaseous diffusion flame SO FIRE SAFETY JOURNAL LA English DT Article AB This work is motivated by the urgent need to find an alternative to the banned halogen-based fire suppressing agents. Fine water mist is a contending alternative especially in total flooding applications. To obtain an optimum design of a water mist fire suppression system, one needs to understand the mechanisms of fire suspension by water mist. This paper presents a study of the relative contributions of the suppression mechanisms in a gaseous diffusion flame. A modified Wolfhard-Parker burner was used to measure temperature drops in a 2D methane diffusion flame, when various quantities of nitrogen, steam and water mist were added independently in a co-flow arrangement. A simple model of the flame was used to estimate the heat generation and loss processes taking place in the flame when small amounts of various suppressants were added. The results of both experiments and the analysis show that in a co-flow arrangement the addition of small quantities of fine water mist has more gas phase cooling effect on the flame than oxygen dilution effect. Published by Elsevier Science Ltd. C1 USN, Res Lab, Navy Technol Ctr Safety & Survivabil, Washington, DC 20375 USA. George Washington Univ, CMEE Dept, Washington, DC USA. RP Ndubizu, CC (reprint author), USN, Res Lab, Navy Technol Ctr Safety & Survivabil, Washington, DC 20375 USA. EM cndubizu@castor.nrl.navy.mil NR 22 TC 41 Z9 55 U1 1 U2 14 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0379-7112 J9 FIRE SAFETY J JI Fire Saf. J. PD OCT PY 1998 VL 31 IS 3 BP 253 EP 276 DI 10.1016/S0379-7112(98)00007-1 PG 24 WC Engineering, Civil; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 120NC UT WOS:000075961600005 ER PT J AU Bosshard, M AF Bosshard, M TI 'Amour noir' SO FRENCH REVIEW LA French DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Bosshard, M (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN TEACH FRENCH PI CHAMPAIGN PA 57 EAST ARMORY AVE, CHAMPAIGN, IL 61820 USA SN 0016-111X J9 FR REV JI Fr. Rev. PD OCT PY 1998 VL 72 IS 1 BP 161 EP 162 PG 2 WC Literature, Romance SC Literature GA 133GX UT WOS:000076679800052 ER PT J AU Meyer, JR Olafsen, LJ Aifer, EH Bewley, WW Felix, CL Vurgaftman, I Yang, MJ Goldberg, L Zhang, D Lin, CH Pei, SS Chow, DH AF Meyer, JR Olafsen, LJ Aifer, EH Bewley, WW Felix, CL Vurgaftman, I Yang, MJ Goldberg, L Zhang, D Lin, CH Pei, SS Chow, DH TI Type II W, interband cascade and vertical-cavity surface-emitting mid-IR lasers SO IEE PROCEEDINGS-OPTOELECTRONICS LA English DT Article; Proceedings Paper CT 2nd International Conference on Mid-IR Optoelectronics - Materials and Devices (MIOMD 98) CY MAR, 1998 CL PRAGUE, CZECH REPUBLIC DE mid-infrared (IR) laser performance; W-well structure ID QUANTUM-WELL LASERS; MIDWAVE-INFRARED-LASERS; MU-M; ROOM-TEMPERATURE; THEORETICAL PERFORMANCE; SUPERLATTICE AB The authors review recent demonstrations of improved mid-IR laser performance when a type II 'W-well' structure is incorporated into the active region. The W configuration consists of a hole quantum well (e.g. GaSb or GaInSb) between electron quantum wells (e.g. InAs) in order to maximise the gain while suppressing nonradiative Auger losses. Optically pumped W lasers recently produced more than 1.4 W per facet peak power for pulsed operation at 300 K. An interband cascade laser with a W active region (W-ICL) has operated up to 286 K. The first III-V mid-IR VCSEL (lambda = 2.9 mu m) with a W active region has lased up to 280 K for pulsed operation and to 160 K for cw, with a cw threshold of only 4 mW for a 6 mu m spot at 78 K. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Houston, Ctr Space Vacuum Epitaxy, Houston, TX 77204 USA. Hughes Res Labs, Malibu, CA 90265 USA. RP Meyer, JR (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Olafsen, Linda/G-4996-2013 NR 28 TC 38 Z9 39 U1 3 U2 13 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1350-2433 J9 IEE P-OPTOELECTRON JI IEE Proc.-Optoelectron. PD OCT PY 1998 VL 145 IS 5 BP 275 EP 280 DI 10.1049/ip-opt:19982304 PG 6 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA 148EV UT WOS:000077492500007 ER PT J AU Chen, VC Miceli, WJ AF Chen, VC Miceli, WJ TI Time-varying spectral analysis for radar imaging of manoeuvring targets SO IEE PROCEEDINGS-RADAR SONAR AND NAVIGATION LA English DT Article DE spectral analysis; radar imaging ID FREQUENCY AB Fourier transforms are the basis for conventional radar range-Doppler imaging. Target rotation during the coherent integration time results in a time-varying Doppler frequency shift that produces, after Fourier transform, a smeared Doppler spectrum and a blurred image. Sophisticated motion compensation algorithms must be applied to obtain focused images using Fourier techniques. However, image blurring can be mitigated without resorting to sophisticated focusing algorithms by using time-varying spectral analysis in place of the Fourier analysis for Doppler processing. Various methods of time-varying spectral analysis are described and compared. Range-Doppler images of manoeuvring aircraft produced by conventional Fourier analysis are then compared with those produced by time-varying spectral analysis. A quantitative simulation illustrates the benefit of using the latter. C1 USN, Res Lab, Div Radar, Washington, DC 20375 USA. Off Naval Res, Arlington, VA 22217 USA. RP Chen, VC (reprint author), USN, Res Lab, Div Radar, Code 5311, Washington, DC 20375 USA. NR 12 TC 66 Z9 79 U1 0 U2 0 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1350-2395 J9 IEE P-RADAR SON NAV JI IEE Proc.-Radar Sonar Navig. PD OCT PY 1998 VL 145 IS 5 BP 262 EP 268 DI 10.1049/ip-rsn:19982220 PG 7 WC Telecommunications SC Telecommunications GA 138LN UT WOS:000076973500003 ER PT J AU Lee, JS Jansen, RW Schuler, DL Ainsworth, TL Marmorino, GO Chubb, SR AF Lee, JS Jansen, RW Schuler, DL Ainsworth, TL Marmorino, GO Chubb, SR TI Polarimetric analysis and modeling of multifrequency SAR signatures from Gulf Stream fronts SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE modeling; radar polarimetry; sea surface electromagnetic scattering; synthetic aperture radar ID SYNTHETIC APERTURE RADAR; SURFACE; WIND; OCEAN; WAVES; SCATTERING; SPECTRUM AB Using airborne synthetic aperture radar data from the 1990 Gulf Stream Experiment, this paper investigates the polarization and wavelength dependence of radar signatures for narrow fronts with converging hows occurring within the Gulf Stream. The signal-to-background ratios of the cross-polarization backscatter return from a convergent front were found much higher than those of copolarization returns, when the flight path is crossing the front. However, a second convergent front, imaged at 45 degrees, showed that the signal-to-background ratios are nearly equal for co- and cross-polarizations. A polarimetric procedure, which has been successfully used to measure terrain slopes and to generate elevation maps, is applied to the convergent front to explain the polarization and imaging geometry dependence of these radar responses. A theoretical modeling of radar modulation using an ocean wave model and a composite-Bragg scattering model, which incorporates the effect of breaking waves, was developed. Calculations with the model agree reasonable well with the radar measurements at various polarizations for three radar frequencies: P-band (68 cm in wavelength), L-hand (24 cm), and C-band (5.7 cm). C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Lee, JS (reprint author), USN, Res Lab, Remote Sensing Div, Code 7263, Washington, DC 20375 USA. NR 26 TC 25 Z9 27 U1 2 U2 15 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD OCT PY 1998 VL 23 IS 4 BP 322 EP 333 DI 10.1109/48.725228 PG 12 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA 129TV UT WOS:000076479800002 ER PT J AU Novarini, JC Keiffer, RS Norton, GV AF Novarini, JC Keiffer, RS Norton, GV TI A model for variations in the range and depth dependence of the sound speed and attenuation induced by bubble clouds under wind-driven sea surfaces SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE attenuation; bubbles; sound speed ID WAVES; OCEAN; PROPAGATION; POPULATIONS; DISPERSION; WATER AB When modeling sound propagation through the uppermost layers of the ocean, the presence of bubble clouds cannot be ignored. Their existence can convert a range-independent sound propagation problem into a range-dependent one. Measurements show that strong changes in sound speed and attenuation are produced by the presence of swarms of microbubbles which can be depicted as patchy clouds superimposed on a very weak background layer. While models suitable for use in acoustic calculations are available for the homogeneous bubble layer (which results from long time averages of the total bubble population), no similar parameterizations are available for the more realistic inhomogeneous bubble layer. Based on available information and within the framework of a classification scheme for bubble plumes proposed by Monahan, a model for the range and depth dependence of the bubbly environment is developed to fill this void. This model, which generates a possible realization of the bubbly environment, is then used to calculate the frequency-dependent change in the sound speed and attenuation induced by the presence of the bubbles plumes. Time evolution is not addressed in this work. C1 Planning Syst Inc, Long Beach, MS 39560 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Planning Syst Inc, Long Beach, MS 39560 USA. NR 34 TC 28 Z9 28 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0364-9059 EI 1558-1691 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD OCT PY 1998 VL 23 IS 4 BP 423 EP 438 DI 10.1109/48.725236 PG 16 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA 129TV UT WOS:000076479800010 ER PT J AU Blair, WD Watson, GA Kirubarajan, T Bar-Shalom, Y AF Blair, WD Watson, GA Kirubarajan, T Bar-Shalom, Y TI Benchmark for radar allocation and tracking in ECM SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article AB A benchmark problem for tracking maneuvering targets is presented. The benchmark problem involves beam pointing control of a phased array (i.e., agile beam) radar against highly maneuvering targets in the presence of false alarms (FAs) and electronic counter measurements (ECM), The testbed simulation described includes the effects of target amplitude fluctuations, beamshape, missed detections, FAs, finite resolution, target maneuvers, and track loss. Multiple waveforms are included in the benchmark so that the radar energy can be coordinated with the tracking algorithm. The ECM includes a standoff jammer (SOJ) broadcasting wideband noise and targets attempting range gate pull off (RGPO). The limits on the position and maneuverability of the targets are given along with descriptions of six target trajectories. The "best" tracking algorithm is the one that minimizes a weighted average of the radar energy and radar time, while satisfying a constraint of 4% on the maximum number of lost tracks. The radar model, the ECM techniques, the target scenarios, and performance criteria for the benchmark are presented. C1 USN, Ctr Surface Warfare, Dahlgren Div, Syst Res & Technol Dept, Dahlgren, VA 22448 USA. Univ Connecticut, Dept Elect & Syst Engn, Storrs, CT 06269 USA. Georgia Tech Res Inst, SEAL, Symrna, GA 30080 USA. RP Blair, WD (reprint author), Georgia Tech Res Inst, SEAL, 7220 Richardson Rd, Symrna, GA 30080 USA. RI Kirubarajan, Thia/A-9770-2009 NR 22 TC 81 Z9 93 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD OCT PY 1998 VL 34 IS 4 BP 1097 EP 1114 DI 10.1109/7.722694 PG 18 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 127WF UT WOS:000076373000004 ER PT J AU Kirubarajan, T Bar-Shalom, Y Blair, WD Watson, GA AF Kirubarajan, T Bar-Shalom, Y Blair, WD Watson, GA TI IMMPDAF for radar management and tracking benchmark with ECM SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID MULTIPLE AB A framework is presented for controlling a phased array radar for tracking highly maneuvering targets in the presence of false alarms (FAs) and electronic countermeasures (ECMs). Algorithms are presented for track formation and maintenance; adaptive selection of target revisit interval, waveform and detection threshold; and neutralizing techniques for ECM, namely, against a standoff jammer (SOJ) and range gate pull off (RGPO), The interacting multiple model (IMM) estimator in combination with the probabilistic data association (PDA) technique is used for tracking. A constant false alarm rate (CFAR) approach is used to adaptively select the detection threshold and radar waveform, countering the effect of jammer-induced false measurements. The revisit interval is selected adaptively, based on the predicted angular innovation standard deviations. This tracker/radar-resource-allocator provides a complete solution to the benchmark problem for target tracking and radar control (presented in the companion paper), Simulation results show an average sampling interval of about 2.5 s while maintaining a track loss less than the maximum allowed 4%. C1 Univ Connecticut, Dept Elect & Syst Engn, Storrs, CT 06269 USA. Georgia Tech Res Inst, SEAL, Smyrna, GA 30080 USA. USN, Ctr Surface Warfare, Dahlgren Div, Syst Res & Technol Dept, Dahlgren, VA 22448 USA. RP Kirubarajan, T (reprint author), Univ Connecticut, Dept Elect & Syst Engn, U157,260 Glenbrook Rd, Storrs, CT 06269 USA. RI Kirubarajan, Thia/A-9770-2009 NR 23 TC 101 Z9 136 U1 0 U2 11 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD OCT PY 1998 VL 34 IS 4 BP 1115 EP 1134 DI 10.1109/7.722696 PG 20 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 127WF UT WOS:000076373000005 ER PT J AU Hanson, GA Iltis, RA Kenney, C AF Hanson, GA Iltis, RA Kenney, C TI Minimax detection for signals with unknown parameters SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article AB Minimax detectors are often used for the detection of signals with unknown parameters in additive white Gaussian noise. Several minimax strategies are discussed for both real and complex signals, including one based on the least favorable distribution of the unknown parameters and a second, distribution-free method based on the worst case parameter values, Also discussed are the relationships between these minimax detectors and equal correlation filters for real signals and equal deflection quadratic detectors for complex signals. Conditions are given under which the two different minimax strategies produce identical detectors. C1 USN, Air Warfare Ctr, Weapons Div, China Lake, CA 93555 USA. Univ Calif Santa Barbara, Dept Elect & Comp Engn, Commun Networks Lab, Santa Barbara, CA 93106 USA. RP Hanson, GA (reprint author), USN, Air Warfare Ctr, Weapons Div, Code 472C00D, China Lake, CA 93555 USA. NR 12 TC 3 Z9 3 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD OCT PY 1998 VL 34 IS 4 BP 1184 EP 1192 DI 10.1109/7.722706 PG 9 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 127WF UT WOS:000076373000009 ER PT J AU Gerlach, K AF Gerlach, K TI Thinned spectrum ultrawideband waveforms using stepped-frequency polyphase codes SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Letter AB An ultrawideband (UWB) radar can interfere with external RF sources because of the mutual occupancy of the same frequency band. A stepped-frequency polyphase code (SFPC) waveform is proposed as a generic UWB waveform whose interference with the external RF sources is significantly reduced. The subpulses of the individual stepped-frequency (SF) pulses are phase coded using small phase perburations. This results in a waveform which places nulls at the frequency locations of the external RF sources. Because the phase perturbations are small, a mismatched filter which uses the unperturbed pulses (no phase modulation) as a reference signal results in a simple receiver design and a small mismatch loss on receive. Furthermore, the proposed methodology also has application to narrowband or wideband radars. C1 USN, Res Lab, Washington, DC 20375 USA. RP Gerlach, K (reprint author), USN, Res Lab, Code 5341,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 4 TC 25 Z9 25 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD OCT PY 1998 VL 34 IS 4 BP 1356 EP 1361 DI 10.1109/7.722721 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 127WF UT WOS:000076373000024 ER PT J AU Kamgar-Parsi, B Kamgar-Parsi, B AF Kamgar-Parsi, B Kamgar-Parsi, B TI Quantization error in regular grids: Triangular pixels SO IEEE TRANSACTIONS ON IMAGE PROCESSING LA English DT Letter DE quantization error; spatial quantization; triangular pixels; 2-D regular grids AB Quantization of the image plane into pixels results in the loss of the trite location of features within pixels and introduces an error in ang quantity computed from feature positions in the image. Here, we derive closed-form, analytic expressions for the error distribution function, thr mean absolute error (MAE), and the mean square error (MSE) due to triangular tessellation, for differentiable functions of an arbitrary number of independently quantized points, using a linear approximation of the function. These quantities are essential in examining the intrinsic sensitivity of image professing algorithms. Square and hexagonal pixels were treated in previous papers. An interesting result is that for all possible cases 0.99 < (D) over bar(T)/(D) over bar(S) < 1.13, where (D) over bar(T) and (D) over bar(S) are the MAE in triangular and square tessellations. C1 USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. RP Kamgar-Parsi, B (reprint author), USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. EM kamgar@aic.nrl.navy.mil NR 13 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1057-7149 J9 IEEE T IMAGE PROCESS JI IEEE Trans. Image Process. PD OCT PY 1998 VL 7 IS 10 BP 1496 EP 1500 DI 10.1109/83.718490 PG 5 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 121TE UT WOS:000076029400012 PM 18276216 ER PT J AU Manheimer, WM Fernsler, RF Gitlin, MS AF Manheimer, WM Fernsler, RF Gitlin, MS TI High power, fast, microwave components based on beam generated plasmas SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE beam produced plasma; hollow cathode; increasing phased array angular coverage; microwave switch; plasma microwave component ID PARAMETRIC-INSTABILITIES; PSEUDOSPARK DISCHARGES; ELECTRON-BEAM; MIRROR; SHEET AB It is shown that the agile mirror plasma, under development as a device to simply and cheaply give electronic steering to microwave beams, also has application as a fast, electronically controlled, high power reflector, or phase shifter, In a radar system, this can lead to such applications as pulse to pulse polarization agility and electronic control of antenna gain, as well as to innovative approaches to high power millimeter wave circulators, The basic theory of the enhanced glow plasma is also developed. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Inst Phys Appl, Nizhnii Novgorod, Russia. RP Manheimer, WM (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. EM manheime@ccf.nrl.navy.mil; gitlin@appl.sci-nnov.ru NR 43 TC 18 Z9 20 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD OCT PY 1998 VL 26 IS 5 BP 1543 EP 1555 DI 10.1109/27.736059 PG 13 WC Physics, Fluids & Plasmas SC Physics GA 147EM UT WOS:000077475400020 ER PT J AU Sarkar, N Yun, XP Ellis, R AF Sarkar, N Yun, XP Ellis, R TI Live-constraint-based control for contact transitions SO IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION LA English DT Article DE contact transition; force control; impulsive constraints; live constraints ID IMPACT CONTROL; ADAPTIVE-CONTROL; MANIPULATORS; ROBOTS; FEEDBACK AB Many manipulation tasks involve transition from unconstrained to constrained motion marked by the contact with a constrained surface. This phenomenon divides the task into more than one phase, each of which requires a different control strategy. Switching from one control strategy to another leads to control discontinuities. This paper seeks to design a controller that avoids such discontinuities. The principle is based on the analysis of impulsive constraints. It is argued that, in theory, such a discontinuity can be avoided by modeling the cause of the force discontinuity of the end-effector as the velocity discontinuity of the constraint surface as opposed to the discontinuity of the Lagrange multiplier. This velocity discontinuity can then be dealt with by a continuous control strategy. A controller is designed based on this principle. Input-output linearization is performed to linearize and decouple the system. Simulation and experimental results are presented to demonstrate the effectiveness of this new approach. C1 Univ Hawaii Manoa, Dept Mech Engn, Honolulu, HI 96822 USA. USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. Queens Univ, Dept Comp & Informat Sci, Kingston, ON K7L 3N6, Canada. RP Univ Hawaii Manoa, Dept Mech Engn, Honolulu, HI 96822 USA. NR 34 TC 11 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1042-296X J9 IEEE T ROBOTIC AUTOM JI IEEE Trans. Robot. Autom. PD OCT PY 1998 VL 14 IS 5 BP 743 EP 754 DI 10.1109/70.720350 PG 12 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA 123HF UT WOS:000076119200009 ER PT J AU Kanayama, YJ Krahn, GW AF Kanayama, YJ Krahn, GW TI Theory of two-dimensional transformations SO IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION LA English DT Article DE group theory; heterogeneous transformations; trajectory generation; transformation; two-dimensional transformation AB This paper proposes a new "heterogeneous" two-dimensional (2-D) transformation group [T, o] to solve motion analysis/planning problems in robotics. In this theory, we use a 3 x 1 matrix to represent a transformation as opposed to a 3 x 3 matrix in the homogeneous formulation, First, this theory is as capable as the homogeneous theory. Because of the minimal size, its implementation requires less memory space and less computation time, and it does not have the rotational matrix inconsistency problem. Furthermore, the raw rotation angle theta is more useful than the trigonometric values, cos theta and sin theta, in the homogeneous transformations. This paper also discusses how to apply the group [T, o] to solve problems related to motion analysis/planning, trajectory generation, and others. This heterogeneous formulation has been successfully implemented in the MML software system for the autonomous mobile robot Yamabico-11 developed at the Naval Postgraduate School. C1 USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. US Mil Acad, Dept Math Sci, West Point, NY 10996 USA. RP USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. EM kanayama@cs.nps.navy.mil; ag2609@usma2.usma.edu NR 14 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1042-296X J9 IEEE T ROBOTIC AUTOM JI IEEE Trans. Robot. Autom. PD OCT PY 1998 VL 14 IS 5 BP 827 EP 834 DI 10.1109/70.720359 PG 8 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA 123HF UT WOS:000076119200018 ER PT J AU Kimmel, EC Carpenter, RL Smith, EA Reboulet, JE Black, BH AF Kimmel, EC Carpenter, RL Smith, EA Reboulet, JE Black, BH TI Physiologic models for comparison of inhalation dose between laboratory and field-generated atmospheres of a dry powder fire suppressant SO INHALATION TOXICOLOGY LA English DT Article ID CARBON-MONOXIDE; PARTICLE DEPOSITION; RESPIRATORY-TRACT; LUNG AIRWAYS; CARBOXYHEMOGLOBIN; EXPOSURE; RATS AB SFE, a solid (dry powder) fire extinguishant, has been evaluated for fire suppression. A fire suppression atmosphere is achieved from pyrolysis of solid SFE, producing an atmosphere consisting of SFE pyrolysates (KCl aerosol particles, CO, and CO2). These components were round in differing proportion depending upon the amount of SFE pyrolyzed and type of resting being performed. Although the inhalation toxicity of this atmosphere has been addressed by laboratory studies, the atmospheres under use conditions were observed to vary from those used in the laboratory. Therefore, we devised a method to estimate the effects of these differences on dose. The deposited aerosol dose and formation of carboxyhemoglobin, which presumably reflect potential health risks, from inhalation of SFE in both situations were estimated by mathematical modeling in rats. The effects of CO2 stimulation of ventilation on aerosol particle deposition and carboxyhemoglobin formation were included. The physical and chemical properties of SFE atmospheres generated for large-scale fire suppression testing and for the acute inhalation toxicity evaluation were used as model inputs. Two nominal concentrations of SFE, 50 and 80 g/m(3), were examined in both test systems. Predicted regional dose in the respiratory tract varied between the two cases, but carboxyhemoglobin formation was predicted to be greater for the fire suppression testing atmospheres. C1 Geocenters Inc, Rockville, MD USA. USN, Med Res Inst Detachment Toxicol, Wright Patterson AFB, OH USA. RP Kimmel, EC (reprint author), NMRI, TD2 Bldg 443,2612 5th St, Wright Patterson AFB, OH 45433 USA. NR 33 TC 4 Z9 4 U1 0 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0895-8378 J9 INHAL TOXICOL JI Inhal. Toxicol. PD OCT PY 1998 VL 10 IS 10 BP 905 EP 922 PG 18 WC Toxicology SC Toxicology GA 120VT UT WOS:000075978600001 ER PT J AU Marco, DB Healey, AJ AF Marco, DB Healey, AJ TI Local area navigation using sonar feature extraction and model-based predictive control SO INTERNATIONAL JOURNAL OF SYSTEMS SCIENCE LA English DT Article AB This paper demonstrates a method to navigate an autonomous underwater vehicle in a local area using an acoustic sensor for position information derived from feature detection. A dynamic model of the vehicle response is used for control between location updates. Favorable results have been found using this approach, and precision positioning of the vehicle to centimeters has been accomplished. Another part of the problem is the need to provide a high-frequency update of vehicle position in order to close the positioning servo loops. Using sonar image feature extraction is necessarily time consuming and therefore is performed in a tactical level process providing asynchronous data to the tactical navigator. It follows that some form of fast dead reckoning must be performed in the execution level either by INS-Doppler or by water speed and heading data or by a model-based predictor. This paper deals with the use of model-based predictor technique where knowledge of the dynamic model of the vehicle provides state information to the vehicle positioning control function. The model uncertainty provides errors of course, but these are corrected through asynchronous updates from the feature extracted positions in the tactical level sonar manager. This concept has been verified by both simulation studies and by experimental validation with the Naval Postgradual School Phoenix vehicle. C1 USN, Postgrad Sch, Dept Mech Engn, Autonomous Underwater Vehicles Lab, Monterey, CA 93943 USA. RP Marco, DB (reprint author), USN, Postgrad Sch, Dept Mech Engn, Autonomous Underwater Vehicles Lab, Monterey, CA 93943 USA. NR 14 TC 2 Z9 2 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0020-7721 J9 INT J SYST SCI JI Int. J. Syst. Sci. PD OCT PY 1998 VL 29 IS 10 BP 1123 EP 1133 DI 10.1080/00207729808929602 PG 11 WC Automation & Control Systems; Computer Science, Theory & Methods; Operations Research & Management Science SC Automation & Control Systems; Computer Science; Operations Research & Management Science GA 127MJ UT WOS:000076354600008 ER PT J AU Cristi, R Caccia, M Veruggio, G AF Cristi, R Caccia, M Veruggio, G TI Motion estimation and modeling of the environment for underwater vehicles SO INTERNATIONAL JOURNAL OF SYSTEMS SCIENCE LA English DT Article ID NAVIGATION AB The problem of localizing an underwater vehicle in a structure environment using sonar returns and measured acceleration is addressed. In particular the environment is modeled as a sequence of segments with constant orientation. the combined estimation of the vehicle motion and the orientation of the segments is obtained using an extended Kalman filter based on a suitable state-space model. Several experiments in the test tank show the effectiveness of this technique. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. Ist Automaz Navale, Genoa, Italy. RP Cristi, R (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RI Veruggio, Gianmarco/B-9405-2013; OI Caccia, Massimo/0000-0002-4482-4541 NR 12 TC 5 Z9 6 U1 1 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0020-7721 J9 INT J SYST SCI JI Int. J. Syst. Sci. PD OCT PY 1998 VL 29 IS 10 BP 1135 EP 1143 DI 10.1080/00207729808929603 PG 9 WC Automation & Control Systems; Computer Science, Theory & Methods; Operations Research & Management Science SC Automation & Control Systems; Computer Science; Operations Research & Management Science GA 127MJ UT WOS:000076354600009 ER PT J AU Young, AJ Castellani, JW O'Brien, C Shippee, RL Tikuisis, P Meyer, LG Blanchard, LA Kain, JE Cadarette, BS Sawka, RN AF Young, AJ Castellani, JW O'Brien, C Shippee, RL Tikuisis, P Meyer, LG Blanchard, LA Kain, JE Cadarette, BS Sawka, RN TI Exertional fatigue, sleep loss, and negative energy balance increase susceptibility to hypothermia SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE exhaustion; underfeeding; sleep deprivation; body temperature regulation ID THERMOREGULATORY RESPONSES; COLD WATER; EXERCISE; MEN; THERMOGENESIS; HYPOGLYCEMIA; STARVATION; WOMEN AB The purpose of this study was to determine how chronic exertional fatigue and sleep deprivation coupled with negative energy balance affect thermoregulation during cold exposure. Eight men wearing only shorts and socks sat quietly during 4-h cold air exposure (10 degrees C) immediately after (<2 h, A) they completed 61 days of strenuous military training (energy expenditure similar to 4,150 kcal/day, energy intake similar to 3,300 kcal/day, sleep similar to 4 h/day) and again after short (48 h, SR) and long (109 days, LR) recovery. Body weight decreased 7.4 kg from before training to A, then increased 6.4 kg by SR, with an additional 6.4 kg increase by LR. Body fat averaged 12% during A and SR and increased to 21% during LR. Rectal temperature (T-re) was lower before and during cold air exposure for A than for SR and LR. T-re declined during cold exposure in A and SR but not LR. Mean weighted skin temperature ((T) over bar(sk)) during cold exposure was higher in A and SR than in LR. Metabolic rate increased during all cold exposures, but it was lower during A and LR than SR. The mean body temperature (0.67 T-re 0.33 (T) over bar(sk)) threshold for increasing metabolism was lower during A than SR and LR. Thus chronic exertional fatigue and sleep loss, combined with underfeeding, reduced tissue insulation and blunted metabolic heat production, which compromised maintenance of body temperature. A short period of rest, sleep, and refeeding restored the thermogenic response to cold, but thermal balance in the cold remained compromised until after several weeks of recovery when tissue insulation had been restored. C1 USA, Environm Med Res Inst, Thermal & Mt Med Div, Natick, MA 01760 USA. USN, Aerosp Med Res Lab, Pensacola, FL 32508 USA. Def & Civil Inst Environm Med, N York, ON M3M 3B9, Canada. RP Young, AJ (reprint author), USA, Environm Med Res Inst, Thermal & Mt Med Div, Natick, MA 01760 USA. EM ayoung@natick-ccmail.army.mil NR 31 TC 58 Z9 58 U1 2 U2 8 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 8750-7587 J9 J APPL PHYSIOL JI J. Appl. Physiol. PD OCT PY 1998 VL 85 IS 4 BP 1210 EP 1217 PG 8 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA 126RJ UT WOS:000076306700003 PM 9760307 ER PT J AU Friedrich, M Siskind, DE Torkar, KM AF Friedrich, M Siskind, DE Torkar, KM TI HALOE nitric oxide measurements in view of ionospheric data SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article ID D-REGION; OCCULTATION EXPERIMENT; MODEL; ATMOSPHERE AB The nitric oxide densities obtained by the HALOE instrument aboard the UARS satellite present a unique set of measurements which can practically only be checked against the results of theoretical models or, indirectly, by comparison to ionospheric data. Long-term averages of mesospheric nitric oxide (NO) data are contrasted to D-region electron densities from an empirical model which is based on a large number of appropriate in situ measurements. Electron densities calculated with an ion-chemical model, which uses HALOE [NO] as an input, tend to underestimate empirical electron densities below 80 km and overestimate it above 80 km. The puzzling diurnal asymmetry of [NO] may also be reflected in the electron densities. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Graz Tech Univ, Dept Commun & Wave Propagat, A-8010 Graz, Austria. USN, Res Lab, Washington, DC 20375 USA. Austrian Acad Sci, Space Res Inst, A-8010 Graz, Austria. RP Friedrich, M (reprint author), Graz Tech Univ, Dept Commun & Wave Propagat, Inffeldgasse 12, A-8010 Graz, Austria. NR 25 TC 11 Z9 11 U1 0 U2 0 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 OCT PY 1998 VL 60 IS 15 BP 1445 EP 1457 DI 10.1016/S1364-6826(98)00091-1 PG 13 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 155XK UT WOS:000077971600002 ER PT J AU Campbell, ML AF Campbell, ML TI Rules for determining the ground state of a j-j coupled atom SO JOURNAL OF CHEMICAL EDUCATION LA English DT Article C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP Campbell, ML (reprint author), USN Acad, Dept Chem, Annapolis, MD 21402 USA. NR 10 TC 1 Z9 1 U1 2 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD OCT PY 1998 VL 75 IS 10 BP 1339 EP 1340 PG 2 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA 120NR UT WOS:000075962900038 ER PT J AU Sellami, L Singh, SK Newcomb, RW Rasmussen, A Zaghloul, ME AF Sellami, L Singh, SK Newcomb, RW Rasmussen, A Zaghloul, ME TI VLSI floating resistors for neural type cell arrays SO JOURNAL OF CIRCUITS SYSTEMS AND COMPUTERS LA English DT Article ID CONTROLLED LINEAR RESISTOR; CMOS TECHNOLOGY; VOLTAGE; NETWORKS AB Two novel CMOS circuit designs implementing floating resistors are introduced, using the structure of a two-transistor CMOS bilateral linear resistor in the first configuration and two two-transistor CMOS bilateral linear resistors and cascode current mirrors in the second configuration. Linearity is achieved through nonlinearity cancellation via current mirrors over an applied range of +/-5V. PSpice simulation results using parameters of MOSIS transistors are presented to verify the theory. These floating resistors can be used for coupling weights in VLSI neural-type cell arrays. C1 USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. Univ Maryland, Dept Elect Engn, Microsyst Lab, College Pk, MD 20742 USA. George Washington Univ, Dept Elect Engn & Comp Sci, Washington, DC 20052 USA. RP Sellami, L (reprint author), USN Acad, Dept Elect Engn, 105 Maryland Ave, Annapolis, MD 21402 USA. NR 22 TC 0 Z9 0 U1 1 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-1266 J9 J CIRCUIT SYST COMP JI J. Circuits Syst. Comput. PD OCT-DEC PY 1998 VL 8 IS 5-6 BP 559 EP 569 DI 10.1142/S0218126698000353 PG 11 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 268ZT UT WOS:000084451800004 ER PT J AU Szu, H AF Szu, H TI Special section on wavelet applications SO JOURNAL OF ELECTRONIC IMAGING LA English DT Editorial Material C1 USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Szu, H (reprint author), USN, Ctr Surface Warfare, Dahlgren Code B40,17320 Dahlgren Rd, Dahlgren, VA 22448 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU I S & T - SOC IMAGING SCIENCE TECHNOLOGY PI SPRINGFIELD PA 7003 KILWORTH LANE, SPRINGFIELD, VA 22151 USA SN 1017-9909 J9 J ELECTRON IMAGING JI J. Electron. Imaging PD OCT PY 1998 VL 7 IS 4 BP 717 EP 718 DI 10.1117/1.482658 PG 2 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA 280LC UT WOS:000085103400001 ER PT J AU Grim, MH Szu, H AF Grim, MH Szu, H TI Video compression quality metrics correlation with aided target recognition (ATR) applications SO JOURNAL OF ELECTRONIC IMAGING LA English DT Article AB Tactical battlefield surveillance systems will require the transmission of compressed video to utilize the limited communication bandwidth and data capacity of these systems. Any compression techniques used wilt result in some loss of information. If is important to assess the quality of the output video to determine its performance in aided target recognition applications. The traditional rate of distortion formula is shown by Mallet [S. Mallet, "Understanding wavelet image compression," Proc. SPIE Wavelet Apps. IV 3078, 74-93 (April 1997); "A theory for multiresolution signal decomposition: The wavelet representation," IEEE Trans. Pattern Anal. Mach. Intell. 11, 674-693 (1989)] to be inappropriate for wavelet compression in high compression ratios. The reason is that the histogram changes from atl gray scale to a concentration singularity near the origin of very low bit rate such that the discrete approximation of the density function of the histogram is no longer valid. Thus we cannot theoretically predict the distortion due to wavelet compression. Therefore we conduct an empirical investigation to evaluate the spatial and temporal effects of lossy wavelet compression and reconstruction on tactical infrared video. We quantify localized peak signal-to-noise ratio and feature persistence measure measurements and objective assessment techniques developed by the institute for Telecommunication Sciences, U.S. Department of commerce to assess video impairment based on quality measurements. We therefore measure video degradation rather than absolute video quality which is difficult to quantify. (C) 1998 SPIE and IS&T. [51017-9909(98)00704-1]. C1 USN, Ctr Surface Warfare, Dahlgren Lab, Dahlgren, VA 22448 USA. RP Grim, MH (reprint author), USN, Ctr Surface Warfare, Dahlgren Lab, Dahlgren, VA 22448 USA. NR 7 TC 1 Z9 1 U1 0 U2 1 PU I S & T - SOC IMAGING SCIENCE TECHNOLOGY PI SPRINGFIELD PA 7003 KILWORTH LANE, SPRINGFIELD, VA 22151 USA SN 1017-9909 J9 J ELECTRON IMAGING JI J. Electron. Imaging PD OCT PY 1998 VL 7 IS 4 BP 740 EP 745 DI 10.1117/1.482663 PG 6 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA 280LC UT WOS:000085103400004 ER PT J AU Hsu, C Szu, H AF Hsu, C Szu, H TI WaveNet processing brassboards for live video via radio SO JOURNAL OF ELECTRONIC IMAGING LA English DT Article ID WAVELET TRANSFORMS AB Recent advances in areas of both discrete wavelet transforms and continuous wavelet transforms representing human visual system neural networks have resulted in improved video compression, restoration, and filtering techniques. These software techniques are capable of achieving quality performance in video, and the computational complexity requires a special design hardware called WaveNet to run a real time live video through radio. The brassboard integrated with computers can potentially provide us with many applications, including remote sensors, security systems, and commercial and home video teleconferencing. This paper describes a low cost board to support a video compression, restoration, and filter system in real time processing. The WaveNet board has been optimized for wavelet-based image and video compression and enhancement techniques. (C) 1998 SPIE and IS&T. [S1017-9909(98)00904-0]. C1 Trident Syst Inc, Fairfax, VA 22030 USA. USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22446 USA. RP Hsu, C (reprint author), Trident Syst Inc, 10201 Lee Highway, Fairfax, VA 22030 USA. NR 13 TC 15 Z9 15 U1 0 U2 0 PU I S & T - SOC IMAGING SCIENCE TECHNOLOGY PI SPRINGFIELD PA 7003 KILWORTH LANE, SPRINGFIELD, VA 22151 USA SN 1017-9909 J9 J ELECTRON IMAGING JI J. Electron. Imaging PD OCT PY 1998 VL 7 IS 4 BP 755 EP 769 DI 10.1117/1.482662 PG 15 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA 280LC UT WOS:000085103400006 ER PT J AU Noel, SE Szu, HH AF Noel, SE Szu, HH TI Proximity sensing with wavelet-generated video SO JOURNAL OF ELECTRONIC IMAGING LA English DT Article ID SIGNAL AB In this paper we introduce wavelet video processing of proximity sensor signals. Proximity sensing is required for a wide range of military and commercial applications, including weapon fuzing, robotics, and automotive collision avoidance. While our proposed method temporarily increases signal dimension, it eventually performs data compression through the extraction of salient signal features. This data compression in tum reduces the necessary complexity of the remaining computational processing. We demonstrate our method of wavelet video processing via the proximity sensing of nearby objects through their Doppler shift. in doing this we perform a continuous wavelet transform on the Doppler signal, after subjecting if to a time-varying window. We then extract signal features from the resulting wavelet video, which we use as input to paftem recognition neural networks. The networks are trained to estimate the time-varying Doppler shift from the extracted features. We test the estimation performance of the networks, using different degrees of nonlinearity in the frequency shift over time and different levels of noise. We give the analytical result that the signal-to-noise enhancement of our proposed method is at least as good as the square root of the number of video frames, although more work is needed to completely quantify this. Real-time wavelet-based video processing and compression technology recently developed under the DOD WAVENET program offers an exciting opportunity to more fully investigate our proposed method. (C) 1998 SPIE and IS&T. [S1017-9909(98)01004-6]. C1 Univ SW Louisiana, Ctr Adv Comp Studies, Lafayette, LA 70504 USA. USN, Ctr Surface Warfare, Syst Res & Technol Dept, Dahlgren Div, Dahlgren, VA 22448 USA. RP Noel, SE (reprint author), Univ SW Louisiana, Ctr Adv Comp Studies, Lafayette, LA 70504 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU I S & T - SOC IMAGING SCIENCE TECHNOLOGY PI SPRINGFIELD PA 7003 KILWORTH LANE, SPRINGFIELD, VA 22151 USA SN 1017-9909 J9 J ELECTRON IMAGING JI J. Electron. Imaging PD OCT PY 1998 VL 7 IS 4 BP 770 EP 780 DI 10.1117/1.482656 PG 11 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA 280LC UT WOS:000085103400007 ER PT J AU Szu, H Cox, P AF Szu, H Cox, P TI Video Johnson-like criterion for moving vehicle identification SO JOURNAL OF ELECTRONIC IMAGING LA English DT Article ID COMPRESSION AB A wavelet, being a bank of matched filters at a constant fidelity, is appropriate for low bandwidth video communication-compression and is also proposed here to test the video contrast sensitivity surface. This generalization permits us to evaluate the trade-off between the spatial redundancy verses temporal redundancy reductions. This paper addresses the relationship between very low bandwidth video compression and human perception for target discrimination using video. (C) 1998 SPIE and IS&T. [S1017-9909(98)01104-0]. C1 USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22446 USA. Trident Syst Inc, Fairfax, VA 22030 USA. RP Szu, H (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22446 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU I S & T - SOC IMAGING SCIENCE TECHNOLOGY PI SPRINGFIELD PA 7003 KILWORTH LANE, SPRINGFIELD, VA 22151 USA SN 1017-9909 J9 J ELECTRON IMAGING JI J. Electron. Imaging PD OCT PY 1998 VL 7 IS 4 BP 781 EP 784 DI 10.1117/1.482657 PG 4 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA 280LC UT WOS:000085103400008 ER PT J AU Szu, H Do-Duc, H AF Szu, H Do-Duc, H TI Image error resilient and video error concealment codes for wavelet compression and noisy channel communication SO JOURNAL OF ELECTRONIC IMAGING LA English DT Article AB Video compression strategy consists of a tacit tradeoff of the spatial redundancy, whose spatial singularities are captured efficiently in terms of zero-phase symmetric wavelet transform (WT) subband coefficients, with their temporal redundancy. On the other hand, the redundancy is robust under noisy channel, and furthermore, an over reduction spatially may hurt the temporal correspondence principle yielding a large frame rate reduction. The video error resilient codes are built upon the single frame error resilient codes, which must have known positions partitioned carefully in order to protect against wireless channel errors during transmission of the discrete WT coefficients. These coefficients have been compressed based on the traditional compression scheme using scalar quantization, runlength, and Huffman coding. The discrete WT biorthogonal (7, 9) wavelet is used. The code is illustrated with relatively good performance for (480x480x8 bits) forward-looking infrared images, compressed at up to 0.09 bits per pixel, and bit error rates at about 10(-3). Furthermore, in this paper we adopt the single frame error resilient coding and extend to video multiple frames with the help of frame error concealment techniques. An attempt is made to perform decompression error concealment, which is an interpolation from neighborhood in space and time. (C) 1998 SPIE and IS&T. [S1017-9909(98)01204-5]. C1 USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. Def Informat Syst Agcy, JEEDD, Arlington, VA 22203 USA. RP Szu, H (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. NR 11 TC 0 Z9 0 U1 0 U2 1 PU I S & T - SOC IMAGING SCIENCE TECHNOLOGY PI SPRINGFIELD PA 7003 KILWORTH LANE, SPRINGFIELD, VA 22151 USA SN 1017-9909 J9 J ELECTRON IMAGING JI J. Electron. Imaging PD OCT PY 1998 VL 7 IS 4 BP 785 EP 793 DI 10.1117/1.482664 PG 9 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA 280LC UT WOS:000085103400009 ER PT J AU Burlaga, LF Ness, NF Wang, YM Sheeley, NR AF Burlaga, LF Ness, NF Wang, YM Sheeley, NR TI Heliospheric magnetic field strength out to 66 AU: Voyager 1, 1978-1996 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SOLAR-WIND SPEED; RADIAL IMF COMPONENT; ULYSSES OBSERVATIONS; LATITUDINAL DEPENDENCE; OUTER HELIOSPHERE; EXPANSION FACTOR; CYCLE; GRADIENTS; PIONEER-11; EVOLUTION AB We discuss Voyager 1 (V1) observations of the heliospheric magnetic field strength from 1978 through 1996. During this period the distance of V1 from the Sun increased from approximate to 3 AU to 66 AU and its heliographic latitude increased from approximate to 5 degrees S to 33 degrees N. The magnetic field strength profile observed by V1 is consistent with Parker's spiral field model when one considers (1) the solar cycle variation of the observed magnetic field strength at 1 AU, B-1(t) (which is a measure of the source field strength) and (2) the latitudinal and solar cycle variations of the solar wind speed, V(t, theta), Both B-1(t) and V(t, theta) make significant contributions to the variation of the magnetic field strength variations observed by V1. There is no evidence for a "magnetic flux deficit" increasing with distance from the Sun. There is a solar cycle variation of the magnetic field strength in the outer heliosphere, which will affect the modulation of cosmic rays. C1 NASA, Extraterr Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. USN, EO Hulburt Ctr Space Res, Res Lab, Washington, DC 20375 USA. RP Burlaga, LF (reprint author), NASA, Extraterr Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 48 TC 19 Z9 19 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD OCT 1 PY 1998 VL 103 IS A10 BP 23727 EP 23732 DI 10.1029/98JA01433 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 125XL UT WOS:000076262300030 ER PT J AU Levine, BL Cotte, J Small, CC Carroll, RG Riley, JL Bernstein, WB Van Epps, DE Hardwick, RA June, CH AF Levine, BL Cotte, J Small, CC Carroll, RG Riley, JL Bernstein, WB Van Epps, DE Hardwick, RA June, CH TI Large-scale production of CD4+ T cells from HIV-1-infected donors after CD3/CD28 costimulation SO JOURNAL OF HEMATOTHERAPY LA English DT Article ID IMMUNODEFICIENCY-VIRUS INFECTION; ACTIVE ANTIRETROVIRAL THERAPY; ALLOGENEIC BONE-MARROW; EX-VIVO EXPANSION; ADOPTIVE IMMUNOTHERAPY; CD28 COSTIMULATION; KILLER-CELLS; CANCER-PATIENTS; HIV; LYMPHOCYTES AB We describe a procedure for large-scale enrichment, growth, and harvesting CD4+ T cells, This method may be effective for HIV-1 immunotherapy, as the mode of stimulation, with anti-CD3 plus anti-CD28 coated beads (CD3/CD28 beads) induces a potent antiviral effect. PBMC were obtained by density gradient centrifugation of an apheresis product. Monocytes/macrophages were removed by incubating PBMC with beads coated with IgG, The cells were then magnetically depleted of B cells and CD8+ cells with mouse anti-CD20 and anti-CD8 MAbs and sheep antimouse coated beads, The remaining cells were >80% CD4+ and were transferred to gas-permeable bags containing CD3/CD28 beads and cultured in a closed system. After 14 days, the cell number increased an average of 37-fold, and cells were nearly 100% CD4+, Viral load, assessed by DNA PCR for HIV-1 gag, decreased >10-fold during culture in the absence of antiretroviral agents, Removal of CD3/CD28 beads from the cell suspension was accomplished by passing cells plus beads (3-30 x 10(9) cells in 2-12 L) over a MaxSep(R) magnetic separator using gravity-driven flow, The cells were then concentrated to 300 mi in an automated centrifuge, This process allows safe and efficient growth of large numbers of CD4+ T cells from HIV-1+ donors. C1 USN, Med Res Inst, Immune Cell Biol Program, Bethesda, MD 20889 USA. Henry M Jackson Fdn Adv Mil Med, US Mil HIV Res Program, Bethesda, MD 20889 USA. Walter Reed Army Inst Res, Div Retrovirol, Rockville, MD 20850 USA. Uniformed Serv Univ Hlth Sci, Dept Med, Bethesda, MD 20889 USA. Nexell Therapeut Inc, Irvine, CA 92618 USA. RP Levine, BL (reprint author), USN, Med Res Inst, Immune Cell Biol Program, Bethesda, MD 20889 USA. RI Levine, Bruce/D-1688-2009; OI Riley, James/0000-0002-1057-576X NR 39 TC 82 Z9 83 U1 0 U2 6 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1061-6128 J9 J HEMATOTHER JI J. Hematother. PD OCT PY 1998 VL 7 IS 5 BP 437 EP 448 DI 10.1089/scd.1.1998.7.437 PG 12 WC Hematology; Medicine, Research & Experimental; Transplantation SC Hematology; Research & Experimental Medicine; Transplantation GA 139JG UT WOS:000077024500006 PM 9829318 ER PT J AU Brodine, SK Shafer, MA Shaffer, RA Boyer, CE Putnam, SD Wignall, FS Thomas, RJ Bales, B Schachter, J AF Brodine, SK Shafer, MA Shaffer, RA Boyer, CE Putnam, SD Wignall, FS Thomas, RJ Bales, B Schachter, J TI Asymptomatic sexually transmitted disease prevalence in four military populations: Application of DNA amplification assays for Chlamydia and gonorrhea screening SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID LIGASE CHAIN-REACTION; TRACHOMATIS INFECTION; URETHRAL INFECTIONS; URINE; MEN; DIAGNOSIS AB The prevalence of asymptomatic chlamydial and gonococcal infections in male and female military populations was determined using urine-based ligase chain reaction DNA amplification assays (DAAs). Cross-sectional surveys in four military settings revealed an overall prevalence of asymptomatic chlamydial infection of 4.2% (56/1338), This included 3.4% (21/618) of Western Pacific shipboard US Marine Corps enlisted men; 5.2% (21/406) of male marines shore-based in Okinawa, Japan; 2.7% (5/183) of female enlisted US Navy subtender personnel in dry dock; and 6.9% (9/131) of shore-based female naval personnel in San Die,oo. No gonococcal infections were detected. All subjects were treated within 2 weeks of screening; none of them had progressed to symptomatic disease. General population-based screening for asymptomatic sexually transmitted diseases, and in particular chlamydial infection, can be successfully implemented using urine-based DAA tests. Benefits are maximized in a population in which compliance for follow-up therapy is high. C1 USN, Hlth Res Ctr, Hlth Sci & Epidemiol Dept, San Diego, CA 92186 USA. USN, Environm Prevent Med Unit 5, San Diego, CA 92186 USA. Univ Calif San Francisco, Dept Pediat, Div Adolescent Med, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Lab Med, San Francisco, CA 94143 USA. Navy Med Res Unit 2, Jakarta, Indonesia. Marine Expeditionary Forces, Okinawa, Japan. RP Brodine, SK (reprint author), USN, Hlth Res Ctr, Hlth Sci & Epidemiol Dept, POB 85122, San Diego, CA 92186 USA. NR 15 TC 37 Z9 39 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0022-1899 J9 J INFECT DIS JI J. Infect. Dis. PD OCT PY 1998 VL 178 IS 4 BP 1202 EP 1204 DI 10.1086/515685 PG 3 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 125QF UT WOS:000076248000045 PM 9806061 ER PT J AU Seitzman, LE AF Seitzman, LE TI Mechanical properties from instrumented indentation: Uncertainties due to tip-shape correction SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID NANOINDENTATION; CURVES; LOAD AB The quality of hardness H and indentation modulus E* measurements from instrumented indentation is investigated. Load-displacement data from glass and sapphire are obtained by Vickers indentation and converted to H and E* through a series of equations, including those for tip-shape correction. The quality of H and E* is determined by calculating the statistical uncertainty at each step and propagating the uncertainty to the next step. Conventional tip-shape corrections, assuming either constant hardness or constant modulus, introduce significant errors in H and E* when single, continuous correction functions are used. Piecewise correction functions are shown to improve the quality of H and E*. This investigation demonstrates the importance of calculating and propagating uncertainty at each step when converting instrumented indentation load-displacement data to mechanical properties. C1 USN, Res Lab, Washington, DC 20375 USA. RP Seitzman, LE (reprint author), Caterpillar Inc, Tech Ctr E 854, POB 1875, Peoria, IL 61656 USA. NR 19 TC 21 Z9 25 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD OCT PY 1998 VL 13 IS 10 BP 2936 EP 2944 DI 10.1557/JMR.1998.0401 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA 127QM UT WOS:000076362100031 ER PT J AU Dunn, DN Seitzman, LE Singer, IL AF Dunn, DN Seitzman, LE Singer, IL TI MoS2 deposited by ion beam assisted deposition: 2H or random layer structure? SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID TRANSMISSION ELECTRON-MICROSCOPY; THIN-FILMS; COATINGS AB The structure of MoS2 films grown by ion beam assisted deposition is investigated using transmission electron microscopy. Films consist of stacks of S-Mo-S planes with a [001] texture; however, three-dimensional crystal symmetry is disrupted by a high density of planar defects. Selected area electron diffraction patterns show (hk0) and (00l) reflections, features similar to a random layer structure, as well as diffuse (103) reflections. It is suggested that these films do not have a true random layer structure, but rather a two-dimensional structure formed by nonrandom in-plane translations. C1 USN, Res Lab, Washington, DC 20375 USA. RP Dunn, DN (reprint author), USN, Res Lab, Code 6176, Washington, DC 20375 USA. NR 21 TC 15 Z9 15 U1 3 U2 10 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD OCT PY 1998 VL 13 IS 10 BP 3001 EP 3007 DI 10.1557/JMR.1998.0410 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 127QM UT WOS:000076362100040 ER PT J AU Guha, S Leppert, VJ Risbud, SH AF Guha, S Leppert, VJ Risbud, SH TI Identification of the electronic states of Se-2(-) molecules embedded in borosilicate glasses and in Se-based nanometer sized crystals SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID SEMICONDUCTOR-DOPED GLASSES; OPTICAL-PROPERTIES; PBSE AB Electron spin resonance (ESR), Raman, and photoluminescence spectra were measured to identify the electronic states of Se; molecules embedded in potassium borosilicate glasses. The ESR spectra of all samples show a lineshape that is attributed to orthorhombic symmetry around the molecule. Photoluminescence spectra show a broad luminescence band between 500 and 900 nm that is identified as the pi(u) --> pi(g) transition between the electronic levels of the Se-2(-) molecule. An electron-lattice interaction gives rise to overtones of the fundamental vibration (322 cm(-1)) of the Se; molecule and they are identified by Raman scattering measurements. The role of Se, molecules as surface traps in Se-based semiconductor quantum dots is examined. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Condensed Matter Phys Div, Res Lab, Washington, DC 20375 USA. Univ Calif Davis, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. RP Guha, S (reprint author), USN, Condensed Matter Phys Div, Res Lab, Washington, DC 20375 USA. NR 14 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD OCT PY 1998 VL 240 IS 1-3 BP 43 EP 49 DI 10.1016/S0022-3093(98)00743-1 PG 7 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 134BY UT WOS:000076724000005 ER PT J AU Griscom, DL Mizuguchi, M AF Griscom, DL Mizuguchi, M TI Determination of the visible range optical absorption spectrum of peroxy radicals in gamma-irradiated fused silica SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT Glass and Optical Materials Division / Bragg Gratings, Photosensitivity and Poling in Glass Fibers and Waveguides - Applications and Fundamentals Meeting CY OCT 25-31, 1997 CL WILLIAMSBURG, VIRGINIA SP Amer Ceramic Soc, Optical Soc Amer (OSA), BGPP, IEEE/Laser & Electro-Soc, Corning Inc, Honeywell Inc, Fed Highway Adm, Colonial Williamsburg Fdn ID SELF-TRAPPED HOLES; HIGH-PURITY; DEFECT CENTERS; AMORPHOUS SIO2; RADIATION; OXYGEN; FIBERS; GLASS; BANDS; LIGHT AB Two silicas (Russian KS-4V and an F-doped silica) with <1 ppm cationic impurities, OH contents <5 ppm, and Cl contents <20 ppm have been investigated in optical-fiber forms by differential-optical spectroscopy following 14-MGy(Si) Co-60 gamma irradiation at 27 degrees C and isochronal anneals to 600 degrees C. Bulk samples of the F-doped silica and of two other high-purity silicas (Suprasil F300 and F310) were studied by electron spin resonance (ESR) and isochronal annealing following exposure to (if a gamma-ray dose of 12 MGy(Si) and (ii) the same 12 MGy gamma irradiation plus a subsequent fission-reactor irradiation. The strength of an optical band near 2 eV is shown to correlate with the intensity of the ESR spectrum of peroxy radicals (PORs) as a function of anneal temperature. The peak energy, band width, and oscillator strength of this band are determined to be E-o=1.97 +/- 0.01 eV, W = 0.17 +/- 0.01 eV, and f(POR) = 0.00057 +/- 0.00015, respectively. This POR band overlaps with, and has previously defied separation from, those of the non-bridging-oxygen hole centers (NBOHCs), here fitted by two bands (E-o = 2.19 +/- 0.01 eV, W = 0.51 +/- 0.01 eV and E-o = 2.08 +/- 0.01 eV, W = 0.32 +/- 0.01 eV) with an aggregate oscillator strength f(NBOHC) = 0.00054 +/- 0.00015. The annealing processes of the PORs and NBOHCs displayed a dose-rate dependence, tentatively linked to the effect of dose rate (1 Gy/s vis-a-vis 5.3 Gy/s) on the steady-state self-trapped-hole populations, which in turn determine the equilibrium of radiolytic interstitial oxygen species: O-0 + O-0 reversible arrow O-2. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Tokyo Inst Technol, Interdisciplinary Grad Sch Sci & Engn, Yokohama, Kanagawa 226, Japan. RP Griscom, DL (reprint author), USN, Res Lab, Div Opt Sci, Code 5612, Washington, DC 20375 USA. EM griscom@nrl.navy.mil NR 25 TC 77 Z9 78 U1 4 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD OCT PY 1998 VL 239 IS 1-3 BP 66 EP 77 DI 10.1016/S0022-3093(98)00721-2 PG 12 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 133YJ UT WOS:000076714900006 ER PT J AU Shin, AY Loncarich, DP Hennrikus, WL Case, SR AF Shin, AY Loncarich, DP Hennrikus, WL Case, SR TI A comparison of three methods for measuring patella malalignment in children SO JOURNAL OF PEDIATRIC ORTHOPAEDICS-PART B LA English DT Article DE knee; patella malalignment; pediatric ID ALTA AB This study compared the Insall-Salvati (IS), Blackburne-Peel (BP), and Koshino-Sugimoto (KS) methods for measuring patellar malalignment in children. The IS and BP methods were inaccurate because the traditional landmarks for measurement were absent in the incompletely ossified pediatric knee. The KS method is based on the midpoint of the patella, the distal femoral physis, and the proximal tibial physis. The KS method applied to the extended knee was also inaccurate because of laxity in the patella ligament. However, the KS method applied to the flexed knee was the most accurate method for measuring patella malalignment in children. C1 USN Hosp, Dept Orthopaed Surg & Clin Investigat, San Diego, CA 92134 USA. RP Hennrikus, WL (reprint author), Valley Childrens Hosp, Dept Orthopaed, 3151 N Millbrook Ave, Fresno, CA 93703 USA. OI Shin, Alexander/0000-0001-9658-8192 NR 12 TC 1 Z9 1 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1060-152X J9 J PEDIATR ORTHOP B JI J. Pediatr. Orthop.-Part B PD OCT PY 1998 VL 7 IS 4 BP 303 EP 306 PG 4 WC Orthopedics; Pediatrics SC Orthopedics; Pediatrics GA 224FM UT WOS:000081886800009 PM 9810530 ER PT J AU Petruncio, ET Rosenfeld, LK Paduan, JD AF Petruncio, ET Rosenfeld, LK Paduan, JD TI Observations of the internal tide in Monterey Canyon SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID CONTINENTAL-SHELF; NORTHERN CALIFORNIA; WAVE REFLECTION; BALTIMORE CANYON; BOUNDARY-LAYER; CURRENTS; OCEAN; SLOPE; VARIABILITY; GENERATION AB Data from two shipboard experiments in 1994, designed to observe the semidiurnal internal tide in Monterey Canyon, reveal semidiurnal currents of about 20 cm s(-1), which is an order of magnitude larger than the estimated barotropic tidal currents. The kinetic and potential energy (evidenced by isopycnal displacements of about 50 m) was greatest along paths following the characteristics calculated from linear theory. These energy ray paths are oriented nearly parallel to the canyon floor and may originate from large bathymetric features beyond the mouth of Monterey Bay. Energy propagated shoreward during the April experiment (ITEX1), whereas a standing wave, that is, an internal seiche, was observed in October (ITEX2). The difference is attributed to changes in stratification between the two experiments. Higher energy levels were present during ITEX1, which took place near the spring phase of the fortnightly (14.8 days) cycle in sea level, while ITEX2 occurred close to the neap phase. Further evidence of phase-locking between the surface and internal tides comes from monthlong current and temperature records obtained near the canyon head in 1991. The measured ratio of kinetic to potential energy during both ITEX1 and ITEX2 was only half that predicted by linear theory for freely propagating internal waves, probably a result of the constraining effects of topography. Internal tidal energy dissipation rate estimates for ITEX1 range from 1.3 x 10(-4) to 2.3 X 10(-3) W m(-3), depending on assumptions made about the effect of canyon shape on dissipation. Cross-canyon measurements made during ITEX2 reveal vertical transport of denser water from within the canyon up onto the adjacent continental shelf. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Rosenfeld, LK (reprint author), USN, Postgrad Sch, Dept Oceanog, Code OC-Ro,833 Dyer Rd,Rm 328, Monterey, CA 93943 USA. EM rosenfel@oc.nps.navy.mil NR 86 TC 112 Z9 113 U1 9 U2 15 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 OCT PY 1998 VL 28 IS 10 BP 1873 EP 1903 DI 10.1175/1520-0485(1998)028<1873:OOTITI>2.0.CO;2 PG 31 WC Oceanography SC Oceanography GA 132MQ UT WOS:000076634200002 ER PT J AU Hellberg, CS Manousakis, E AF Hellberg, CS Manousakis, E TI Finding phase separation in the t-J model numerically SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE t-J model; high temperature superconductivity; phase separation ID LUTTINGER-LIQUID INSTABILITY; CORRELATED ELECTRONS; DIAGRAM; SUPERCONDUCTIVITY AB We investigate the phase diagram of the two-dimensional t-J model using two numerical techniques: Green's Function Monte Carlo to calculate the ground-state energy of the model on large lattices, and exact diagonalization on small lattices. We find that phase separation occurs at significantly smaller interaction strengths and larger hole dopings than is indicated by previous studies. This region includes the underdoped cuprate superconductors. At low hole doping, the model phase separates at all interaction strengths. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. Florida State Univ, Ctr Mat Res & Technol, Tallahassee, FL 32306 USA. RP Hellberg, CS (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RI Hellberg, C. Stephen/E-5391-2010 NR 21 TC 6 Z9 6 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1818 EP 1820 DI 10.1016/S0022-3697(98)00113-9 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500034 ER PT J AU Blumberg, G Klein, MV Kadowaki, K Kendziora, C Guptasarma, P Hinks, D AF Blumberg, G Klein, MV Kadowaki, K Kendziora, C Guptasarma, P Hinks, D TI Evolution of magnetic and superconducting fluctuations with doping of high-T-c superconductors: An electronic Raman scattering study SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MA DE Raman scattering; antiferromagnetic correlations; superconducting order ID CUPRATE ANTIFERROMAGNETIC INSULATORS; MOTT-HUBBARD SYSTEMS; SINGLE-CRYSTAL; NORMAL-STATE; BOSE CONDENSATION; SPIN DYNAMICS; GAP; BI2SR2CACU2O8+DELTA; YBA2CU3O7-DELTA; CONTINUUM AB For YBa2Cu3O6+delta and Bi2Sr2CaCu2O8+/-delta superconductors, electronic Raman scattering from high- and low-energy excitations has been studied in relation to the hole doping level, temperature and energy of the incident photons. For underdoped superconductors, it is concluded that short range antiferromagnetic (AF) correlations persist with hole doping and doped single holes are incoherent in the AF environment. Above the superconducting (SC) transition temperature T-c, the system exhibits a sharp Raman resonance of B-1g symmetry and about 75 meV energy and a pseudogap for electron-hole excitations below 75 meV, a manifestation of a partially coherent state forming from doped incoherent quasi-particles. The occupancy of the coherent state increases with cooling until phase ordering at T-c produces a global SC state. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Illinois, NSF Sci & Technol Ctr Superconduct, Urbana, IL 61801 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Inst Chem Phys & Biophys, EE-0001 Tallinn, Estonia. Univ Tsukuba, Inst Mat Sci, Tsukuba, Ibaraki 305, Japan. USN, Res Lab, Washington, DC 20375 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Univ Illinois, NSF Sci & Technol Ctr Superconduct, Urbana, IL 61801 USA. NR 45 TC 20 Z9 20 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 EI 1879-2553 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1932 EP 1936 DI 10.1016/S0022-3697(98)00135-8 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500064 ER PT J AU Kendziora, C AF Kendziora, C TI Gapless superconductivity in Raman studies of cation substituted Bi2Sr2CaCu2O8+delta SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MA ID HIGH-TC SUPERCONDUCTORS; ELECTRONIC-STRUCTURE; GAP; ANISOTROPY AB The electronic Raman scattering (ERS) spectrum of the high-temperature superconductor Bi2Sr2CaCu2O8+delta is studied as a function of cation substitution and oxygen content. In unsubstituted crystals with delta near and above that for the optimal T-c, the ERS spectra show a redistribution of spectral weight below T-c consistent with the opening of a superconducting energy gap at 2 Delta. At low oxygen concentrations and in cation substituted samples with optimal oxygen content, the pair-breaking peak is not observed, displaying instead "gapless" or "pseudogap" spectra. When cation substituted samples are post-annealed in high pressure oxygen, the 2 Delta peak remarkably appears. (C) 1998 Published by Elsevier Science Ltd. C1 USN, Res Lab, Washington, DC 20375 USA. RP USN, Res Lab, Code 6653, Washington, DC 20375 USA. EM kend-zior@ccfsun.nrl.navy.mil NR 18 TC 3 Z9 3 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 EI 1879-2553 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1991 EP 1993 DI 10.1016/S0022-3697(98)00165-6 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500079 ER PT J AU Rudd, RE Pickett, WE AF Rudd, RE Pickett, WE TI The Josephson effect in single spin superconductors SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MA DE Josephson effect; single spin superconductivity; antiferromagnets ID HALF-METALLIC FERROMAGNET; HEAVY-FERMION SUPERCONDUCTORS; POSITRON-ANNIHILATION; PROXIMITY; TRANSPORT; SR2RUO4; NIMNSB; UBE13 AB The Josephson effect provides a primary signature of single spin superconductivity (SSS), the as yet unobserved superconducting state which was proposed recently as a low temperature phase of half-metallic antiferromagnets. These materials are insulating in the spin-down channel, but are metallic in the spin-up channel. The SSS state is characterized by a unique form of p-wave pairing within a single spin channel. We develop the theory of a rich variety of Josephson effects that arise due to the form of the SSS order parameter. Tunneling is allowed at a SSS-SSS' junction, but of course depends on the relative orientation of their order parameters. No current Rows between an SSS and an a-wave BCS system as a result of their orthogonal symmetries, which potentially can be used to distinguish SSS from other superconducting states. Single spin superconductors also offer a means to probe other materials, where tunneling is a litmus rest for any form of "triplet" order parameter. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 SFA Inc, Largo, MD 20774 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Rudd, RE (reprint author), SFA Inc, 1401 McCormick Dr, Largo, MD 20774 USA. EM rudd@dave.nrl.navy.mil OI Rudd, Robert/0000-0002-6632-2681 NR 25 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2074 EP 2077 DI 10.1016/S0022-3697(98)00172-3 PG 4 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500102 ER PT J AU Mazin, II Singh, DJ AF Mazin, II Singh, DJ TI Magnetism and spin-fluctuation induced superconductivity in ruthenates SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE magnetism; ruthenates; spin fluctuation ID ELECTRONIC-STRUCTURE; LAYERED PEROVSKITE; SR2RUO4; STATE; TEMPERATURES; SYMMETRY; HE-3 AB Layered and pseudocubic Ru-based perovskites have been the subject of considerable recent attention, due to their unusual magnetic properties and the discovery of superconductivity in one member of the family, Sr2RuO4. From a magnetic point of view, interest derives from the stable ferromagnetism in SrRuO3, gradually disappearing to a non-magnetic phase upon substituting Sr with isovalent Ca, a very unusual kind of behavior for three-dimensional perovskites. On the superconducting side, interest was stimulated by theoretical conjectures and experimental indications that Sr2RuO4 might be a p-wave superconductor. We report first-principles LSDA calculations for ferromagnetic SrRuO3, antiferromagnetic Sr2YRuO6, non-magnetic CaRuO3, and superconducting Sr2RuO4. In all cases, magnetic properties are well reproduced by the calculations. Anomalous properties are explained in terms of simple TB models and Stoner theory. An important result is that O bears sizable magnetic moments and plays an important role in the formation of the magnetic states. Based on these calculations, we have built a model for the q-dependent Stoner interaction, which we consequently applied to Sr2RuO4 to estimate superconducting and mass-renormalization electron-paramagnon coupling constants. We found that spin-fluctuation induced p-wave superconductivity is possible in Sr2RuO4. The estimated critical temperature, specific heat and susceptibility renormalizations are all in good agreement with the experiment. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. George Mason Univ, Fairfax, VA 22030 USA. RP Mazin, II (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. EM mazin@dave.nrl.navy.mil RI Mazin, Igor/B-6576-2008; Singh, David/I-2416-2012 NR 26 TC 5 Z9 5 U1 1 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2185 EP 2189 DI 10.1016/S0022-3697(98)00210-8 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500128 ER PT J AU Gherman, R AF Gherman, R TI Resolving shoulder dystocia SO JOURNAL OF REPRODUCTIVE MEDICINE LA English DT Letter ID MANEUVER C1 Naval Med Ctr Portsmouth, Dept Obstet & Gynecol, Div Maternal Fetal Med, Portsmouth, VA 23708 USA. RP Gherman, R (reprint author), Naval Med Ctr Portsmouth, Dept Obstet & Gynecol, Div Maternal Fetal Med, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU SCI PRINTERS & PUBL INC PI ST LOUIS PA P.O. DRAWER 12425 8342 OLIVE BLVD, ST LOUIS, MO 63132 USA SN 0024-7758 J9 J REPROD MED JI J. Reprod. Med. PD OCT PY 1998 VL 43 IS 10 BP 922 EP 923 PG 2 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 130TL UT WOS:000076536400016 PM 9800681 ER PT J AU Zeisler-Mashl, KL Pande, CS AF Zeisler-Mashl, KL Pande, CS TI Texture characterization of high-temperature superconductor wires SO JOURNAL OF SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT TMS Superconductivity Session CY FEB, 1998 CL SAN ANTONIO, TEXAS DE high-temperature superconductor; BSCCO tape; texture; pole figure ID GRAIN-BOUNDARY; TAPES; HIGH-J(C); BI-2223 AB Texture measurements have been made for BSCCO tapes produced by dip coating and by powder-in-tube techniques. The texture of the Bi2212 grains was characterized for both c axis texture using (001) pole figures from 008 reflections and a-b axis texture using (115) pole figures. The critical current densities of these tapes were also measured and correlated with texture parameters obtained from contours of the pole figures. For the tapes with good current transport, the arrangement of grains in a crystallographic sense was inferred from the pole figures and was found to be consistent with a model based on global alignment of the c axes and the presence of colonies of grains differing mostly in c axis twist. C1 USN, Res Lab, Mat Sci & Technol Div, Washington, DC 20375 USA. RP Zeisler-Mashl, KL (reprint author), USN, Res Lab, Mat Sci & Technol Div, Washington, DC 20375 USA. NR 15 TC 2 Z9 2 U1 0 U2 2 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0896-1107 J9 J SUPERCOND JI J. Supercond. PD OCT PY 1998 VL 11 IS 5 BP 609 EP 613 DI 10.1023/A:1022691414195 PG 5 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 139ZZ UT WOS:000077062200018 ER PT J AU Yang, TC Yoo, K Yates, T AF Yang, TC Yoo, K Yates, T TI Matched-beam processing: Range tracking with vertical arrays in mismatched environments SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SOURCE LOCALIZATION; SHALLOW-WATER; WAVE-GUIDES; SOUND-SPEED; FIELD; INVERSION AB This paper addresses the problem of range tracking using one or more vertical arrays in certain mismatched shallow-water environments. The objective is to obtain continuous tracking of a target thereby allowing the target to be distinguished from false alarms. It is shown that bottom mismatch can cause large range errors at discrete source ranges as observed in previous experiments. Also, significant range errors (offsets) can result from unknown array tilt. Discrete range errors impede the ability to detect a target by integrating along the target track (track-before-detect) or by a probability based target detection and tracking algorithm. Large range errors impede the ability to localize and track the target from multiple vertical arrays. These problems are addressed using matched-beam processing whereby certain bottom mismatch is minimized by a beam filter and unknown array tilt is estimated by matching the measured beam pattern against the calculated one. Beam filtering and beam matching are simple and convenient methods to implement in practical systems. Comments are also given on other applications using beam domain processing. [S0001-4966(98)00310-5]. C1 USN, Res Lab, Washington, DC 20375 USA. Vector Res Corp, Rockville, MD 20852 USA. RP Yang, TC (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM yates@wave14i.nrl.navy.mil NR 38 TC 12 Z9 13 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD OCT PY 1998 VL 104 IS 4 BP 2174 EP 2188 DI 10.1121/1.423730 PG 15 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 127WW UT WOS:000076374400029 ER PT J AU Rumerman, ML AF Rumerman, ML TI Interaction between a Timoshenko-Mindlin plate and an attached rib SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB In contrast to a thin plate having no shear component of deformation, a Timoshenko-Mindlin plate cannot support a concentrated line dipole moment exerted by a pair of equal and opposite line forces acting normal to its lateral surface. In this paper, it is argued that, in order to account for all the connectivity between a rib and the plate, it is necessary to assume a nonzero width footprint for the rib upon the plate. This footprint is idealized by a connection between the rib and plate along two lines parallel to the rib. The problem posed is one dimensional, with plate responses invariant in the direction of the rib; therefore, along each line of contact, the rib exerts upon the plate only a normal force and a tangential (shear) force perpendicular to the rib. These four initially independent forces combine to produce resultant opposing forces acting on the end of the rib which generate velocities of the rib that can be related to those of the plate. The response quantity of interest is the structural power reflected from the rib due to a wave propagating freely in a direction normal to the rib and incident upon it. It is shown that the rib footprint cannot be set equal to zero if the rib's rotational properties are to have a meaningful influence on the calculated reflected power. [S0001-4966(98)02310-8]. C1 USN, Ctr Surface Warfare, Carderock Div, Signatures Directorate, Bethesda, MD 20817 USA. RP Rumerman, ML (reprint author), USN, Ctr Surface Warfare, Carderock Div, Signatures Directorate, Code 7200,9500 MacArthur Blvd, Bethesda, MD 20817 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD OCT PY 1998 VL 104 IS 4 BP 2213 EP 2219 DI 10.1121/1.423734 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 127WW UT WOS:000076374400034 ER PT J AU Rumerman, ML AF Rumerman, ML TI Range-dependent acoustic radiation from line-driven plates above the bending coincidence frequency SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The leaky waves generated on plates driven in bending above the bending coincidence frequency radiate as extended sources; therefore, the standard saddle point evaluation of the radiated pressure, which yields a far-field result, may not be appropriate at the range of interest. The calculation can be modified by removing the contribution of the leaky waves from the original integrand, evaluating the remaining regular part by the saddle point method, and evaluating the effect of the leaky waves in terms of error functions and residue. Results showing range dependence are presented for radiation by a steel plate in water driven by normal and tangential line forces. The correctness of the results is made plausible by comparing independent calculations of acoustic power passing through a semicircle at finite range. [S0001-4966(98)05510-6]. C1 USN, Ctr Surface Warfare, Carderock Div, Signatures Directorate, Bethesda, MD 20817 USA. RP Rumerman, ML (reprint author), USN, Ctr Surface Warfare, Carderock Div, Signatures Directorate, Code 7200,9500 MacArthur Blvd, Bethesda, MD 20817 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD OCT PY 1998 VL 104 IS 4 BP 2223 EP 2226 DI 10.1121/1.423736 PG 4 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 127WW UT WOS:000076374400036 ER PT J AU Whitmore, RM Anderson, CJ Piper, T AF Whitmore, RM Anderson, CJ Piper, T TI Poroid hidradenoma - A case presentation SO JOURNAL OF THE AMERICAN PODIATRIC MEDICAL ASSOCIATION LA English DT Article AB Poroid hidradenoma is a benign soft-tissue neoplasm with eccrine differentiation. It is the newest addition to a group of neoplasms known as poromas. Although it becomes malignant in less than 1% of cases, its histologic characteristics may resemble those of malignant neoplasms; thus it is easily misdiagnosed. Twenty-one percent of poroid hidradenomas occur in the extremities. The histologic and clinical features of this tumor are presented here, along with a case report. C1 USN, Med Serv Corp, Washington, DC 20350 USA. RP Whitmore, RM (reprint author), USN, Med Serv Corp, Washington, DC 20350 USA. NR 12 TC 2 Z9 3 U1 0 U2 0 PU AMER PODIATRIC MED ASSN PI BETHESDA PA 9312 OLD GEORGETOWN ROAD, BETHESDA, MD 20814-1621 USA SN 0003-0538 J9 J AM PODIAT MED ASSN JI J. Am. Podiatr. Med. Assoc. PD OCT PY 1998 VL 88 IS 10 BP 510 EP 513 PG 4 WC Orthopedics SC Orthopedics GA 127XE UT WOS:000076375200007 PM 9791957 ER PT J AU Wang, PF Cheng, RT Richter, K Gross, ES Sutton, D Gartner, JW AF Wang, PF Cheng, RT Richter, K Gross, ES Sutton, D Gartner, JW TI Modeling tidal hydrodynamics of San Diego Bay, California SO JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION LA English DT Article DE tidal hydrodynamics; modeling; TRIM; San diego Bay; ADCP ID FRANCISCO BAY AB In 1983, current data were collected by the National Oceanic and Atmospheric Administration using mechanical current meters. During 1992 through 1996, acoustic Doppler current profilers as well as mechanical current meters and tide gauges were used. These measurements not only document tides and tidal currents in San Diego Bay, but also provide independent data sets for model calibration and verification. A high resolution (100-m grid), depth-averaged, numerical hydrodynamic model has been implemented for San Diego Bay to describe essential tidal hydrodynamic processes in the bay. The model is calibrated using the 1983 data set and verified using the more recent 1992-1996 data. Discrepancies between model predictions and field data in both model calibration and verification are on the order of the magnitude of uncertainties in the field data. The calibrated and verified numerical model has been used to quantify residence time and dilution and flushing of contaminant effluent into San Diego Bay. Furthermore, the numerical model has become an important research tool in ongoing hydrodynamic and water quality studies and in guiding future field data collection programs. C1 USN, Space & Warfare Syst Ctr, Marine Environm Branch, San Diego, CA 92152 USA. US Geol Survey, Menlo Park, CA 94025 USA. San Diego Supercomp Ctr, San Diego, CA 92186 USA. RP Wang, PF (reprint author), USN, Space & Warfare Syst Ctr, Marine Environm Branch, D362,53475 Strothe Rd, San Diego, CA 92152 USA. NR 17 TC 14 Z9 14 U1 1 U2 5 PU AMER WATER RESOURCES ASSOC PI HERNDON PA 950 HERNDON PARKWAY SUITE 300, HERNDON, VA 20170-5531 USA SN 0043-1370 J9 J AM WATER RESOUR AS JI J. Am. Water Resour. Assoc. PD OCT PY 1998 VL 34 IS 5 BP 1123 EP 1140 DI 10.1111/j.1752-1688.1998.tb04159.x PG 18 WC Engineering, Environmental; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 137MR UT WOS:000076919000013 ER PT J AU Segerman, AM Coffey, SL AF Segerman, AM Coffey, SL TI Ephemeris compression using multiple Fourier series SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article AB An ephemeris compression method has been developed which uses multiple Fourier series. The compression itself is performed upon the Cartesian residuals which result from differencing a numerically integrated ephemeris with an ephemeris generated by a widely-used analytical propagator, such as PPT. An accurate estimate of the ephemeris may then be generated by reconstructing the residuals from the Fourier coefficients and superposing these with the analytical propagator's ephemeris. Statistical results from testing the method with the satellite catalog are presented. C1 USN, Res Lab, GRC Int, Washington, DC 20375 USA. USN, Res Lab, Math & Orbit Dynam Sect, Washington, DC 20375 USA. RP Segerman, AM (reprint author), USN, Res Lab, GRC Int, Code 8233, Washington, DC 20375 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD OCT-DEC PY 1998 VL 46 IS 4 BP 343 EP 359 PG 17 WC Engineering, Aerospace SC Engineering GA 265LX UT WOS:000084246600002 ER PT J AU Minter, CF Cicci, DA AF Minter, CF Cicci, DA TI Improvements in Mars gravity field determination using ridge-type estimation methods SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article ID VENUS GRAVITY; MODEL AB The use of ridge-type estimation methods in determining the proper weighting of the a priori covariance appears to improve the accuracy of the Mars50c gravity field model derived from Viking and Mariner 9 Doppler tracking data. These advanced parameter estimation techniques were applied to the calculation of GM and a (50 x 50) field of harmonic coefficients, representing the gravitational potential of Mars. Calculation of the gravity field coefficients involves solving a large, ill-conditioned system of linear equations, whose solution leads to erroneous estimates if not augmented by appropriate a priori information. In calculating Mars50c, an Lr priori covariance was used in order to provide a set of constraints on the gravity field solution. This study involved the use of ridge-type estimation methods to optimally weight a set of a priori constraints based upon Kaula's Rule in order to obtain more accurate estimates. The computed gravity field, denoted AUMGM9, was compared to Mars50c on the basis of total variance of the solution and residual sum of squares. Analysis of the results show that through the use of ridge-type estimation methods, AUMGM9 provides more accurate gravity field coefficients than does Mars50c. C1 USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. Auburn Univ, Dept Aerosp Engn, Auburn, AL 36849 USA. RP Minter, CF (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Bldg 1200,Code T-13,17320 Dahlgren Rd, Dahlgren, VA 22448 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD OCT-DEC PY 1998 VL 46 IS 4 BP 411 EP 424 PG 14 WC Engineering, Aerospace SC Engineering GA 265LX UT WOS:000084246600006 ER PT J AU Reynolds, CA Palmer, TN AF Reynolds, CA Palmer, TN TI Decaying singular vectors and their impact on analysis and forecast correction SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID 4-DIMENSIONAL VARIATIONAL ASSIMILATION; OPTIMAL PERTURBATIONS; INITIAL CONDITIONS; KALMAN SMOOTHER; ERROR GROWTH; PREDICTABILITY; PREDICTION; NMC; INSTABILITY; CIRCULATION AB The full set of kinetic energy singular values and singular vectors for the forward tangent propagator of a quasigeostrophic potential vorticity model is examined. In contrast to the fastest growing singular vectors, the fastest decaying vectors exhibit a downward and downscale transfer of energy and an eastward tilt with height. The near-neutral singular vectors resemble small-scale noise with no localized structure or coherence between levels. Post-time forecast and analysis correction techniques are examined as a function of the number of singular vectors included in the representation of the inverse of the forward tangent propagator. It is found that for the case when the forecast error is known exactly, the best corrections are obtained when using the full inverse, which includes all of the singular vectors. II is also found that the erroneous projection of the analysis uncertainty onto the fastest decaying singular vectors has a significant detrimental effect on the estimation of analysis error. Therefore, for the more realistic case where the forecast error is known imperfectly, use of the full inverse will result in an inaccurate estimate of analysis errors, and the best corrections are obtained when using an inverse composed only of the growing singular vectors. Running the tangent equations with a negative lime step is a very good approximation to using the full inverse of the forward tangent propagator. C1 USN, Res Lab, Monterey, CA 93943 USA. European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England. RP Reynolds, CA (reprint author), USN, Res Lab, 7 Grace Hopper Ave, Monterey, CA 93943 USA. OI Palmer, Tim/0000-0002-7121-2196; Reynolds, Carolyn/0000-0003-4690-4171 NR 41 TC 32 Z9 32 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD OCT 1 PY 1998 VL 55 IS 19 BP 3005 EP 3023 DI 10.1175/1520-0469(1998)055<3005:DSVATI>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 123ET UT WOS:000076113400001 ER PT J AU Urbach, HB Jones, E AF Urbach, HB Jones, E TI On the conservation of rothalpy in turbomachines SO JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME LA English DT Editorial Material C1 USN, Ctr Surface Warfare, Carderock Div, Annapolis, MD 21402 USA. Univ Maryland, Dept Aerosp Engn, College Pk, MD 20742 USA. RP Urbach, HB (reprint author), USN, Ctr Surface Warfare, Carderock Div, Annapolis, MD 21402 USA. NR 10 TC 0 Z9 0 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0889-504X J9 J TURBOMACH JI J. Turbomach.-Trans. ASME PD OCT PY 1998 VL 120 IS 4 BP 854 EP 855 PG 2 WC Engineering, Mechanical SC Engineering GA 132ZY UT WOS:000076663000028 ER PT J AU Ward, JF Kaplan, GW Mevorach, R Stock, JA Cilento, BG AF Ward, JF Kaplan, GW Mevorach, R Stock, JA Cilento, BG TI Refined microscopic urinalysis for red blood cell morphology in the evaluation of asymptomatic microscopic hematuria in a pediatric population SO JOURNAL OF UROLOGY LA English DT Article DE hematuria; erythrocytes; abnormal; urinalysis ID PHASE-CONTRAST MICROSCOPY; GLOMERULAR HEMATURIA; NONGLOMERULAR HEMATURIA; CHILDREN; DIAGNOSIS; DIFFERENTIATION; ERYTHROCYTES; MICROHEMATURIA; EPIDEMIOLOGY; SEDIMENT AB Purpose: The use of refined microscopic urinalysis for the presence of dysmorphic red blood cells (RBCs) has been evaluated in children and adults with a known source of hematuria. We examined the clinical usefulness of this study in a pediatric population with an unknown source of hematuria. Materials and Methods: Children 12 years old or younger referred for evaluation of asymptomatic microscopic hematuria exhibiting 4 or more RBCs per high power field were enrolled in this study. Patients provided a first morning urine sample subjected to refined urinalysis for RBC morphology. Standard evaluation of patients was performed until a final diagnosis of the hematuria source was identified. Results: A total of 44 patients completed the study. Refined urinalysis revealed pure dysmorphic RBCs in 22 patients, pure isomorphic RBCs in 8 and mixed isomorphic/dysmorphic RBCs in 14. The presence of dysmorphic RBCs correctly predicted a glomerulotubular source of hematuria in 29 of 36 patients (sensitivity 83%, specificity 81%), while the presence of isomorphic RBCs predicted a uroepithelial source of hematuria in 2 of 8 patients (sensitivity 25%, specificity 22%). Hematuria and 2+ proteinuria (100 mg./dl.) were more sensitive (100%) and specific (83%) than the presence of dysmorphic RBCs in predicting glomerulotubular hematuria. Conclusions: We believe that this is a costly test offering Little additional information to the evaluation of microscopic hematuria in children. A thoughtful history and physical examination with microscopic urinalysis and dipstick for proteinuria provide an equal amount of diagnostic information. We do not recommend its routine use in the evaluation of microscopic hematuria in children. C1 USN, Med Ctr, Dept Urol, Div Pediat Urol, San Diego, CA 92134 USA. Childrens Hosp, San Diego, CA USA. Ctr Hlth, San Diego, CA USA. RP Ward, JF (reprint author), USN, Med Ctr, Dept Urol, Div Pediat Urol, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 33 TC 8 Z9 9 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0022-5347 J9 J UROLOGY JI J. Urol. PD OCT PY 1998 VL 160 IS 4 BP 1492 EP 1495 DI 10.1016/S0022-5347(01)62600-4 PG 4 WC Urology & Nephrology SC Urology & Nephrology GA 120YZ UT WOS:000075986600101 PM 9751402 ER PT J AU Riley, JL Levine, BL Craighead, N Francomano, T Kim, D Carroll, RG June, CH AF Riley, JL Levine, BL Craighead, N Francomano, T Kim, D Carroll, RG June, CH TI Native and memory CD4 T cells differ in their susceptibilities to human immunodeficiency virus type 1 infection following CD28 costimulation: Implications for transmission and pathogenesis SO JOURNAL OF VIROLOGY LA English DT Article ID HIV-INFECTION; DENDRITIC CELLS; IN-VITRO; FUSION COFACTOR; LYMPHOCYTES; CHEMOKINE; NAIVE; EXPRESSION; RECEPTOR; SUBSETS AB In vitro evidence suggests that memory CD4(+) cells are preferentially infected by human immunodeficiency virus type 1 (HIV-1), yet studies of HIV-1-infected individuals have failed to detect preferential memory cell depletion. To explore this paradox, we stimulated CD45RA(+) CD4(+) (naive) and CD45RO(+) CD4(+) (memory) cells with antibodies to CD3 and CD28 and infected them with either CCR5-dependent (R5) or CXCR4-dependent (X4) HIV-1 isolates. Naive CD4(+) cells supported less X4 HIV replication than their memory counterparts. However, naive cells were susceptible to R5 viral infection,,while memory cells remained resistant to infection and viral replication. As with the unseparated cells, mixing the naive and memory cells prior to infection resulted in cells resistant to R5 infection and highly susceptible to X4 infection. While both naive and memory CD4(+) subsets downregulated CCR5 expression in response to CD28 costimulation, only the memory cells produced high levels of the beta-chemokines RANTES, MIP-1 alpha, and MIP-1 beta upon stimulation. Neutralization of these beta-chemokines rendered memory CD4(+) cells highly sensitive to infection with R5 HIV-1 isolates, indicating that downregulation of CCR5 is not sufficient to mediate complete protection from CCR5 strains of HIV-I. These results indicate that susceptibility to R5 HIV-1 isolates is determined not only by the level of CCR5 expression but also by the balance of CCR5 expression and beta-chemokine production. Furthermore, our results suggest a model of HIV-1 transmission and pathogenesis in which naive rather than memory CD4(+) T cells serve as the targets for early rounds of HIV-1 replication. C1 USN, Med Res Inst, Immune Cell Biol Program, Bethesda, MD 20889 USA. Walter Reed Army Inst Res, Div Retrovirol, Rockville, MD 20850 USA. Henry M Jackson Fdn Advancement Mil Med, US Mil HIV Res Program, Bethesda, MD 20889 USA. RP June, CH (reprint author), USN, Med Res Inst, Immune Cell Biol Program, Mail Stop 061,8901 Wisconsin Ave, Bethesda, MD 20889 USA. EM junec@nmripo.nmri.nnmc.navy.mil RI Levine, Bruce/D-1688-2009; OI Riley, James/0000-0002-1057-576X NR 71 TC 53 Z9 53 U1 0 U2 2 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0022-538X J9 J VIROL JI J. Virol. PD OCT PY 1998 VL 72 IS 10 BP 8273 EP 8280 PG 8 WC Virology SC Virology GA 118WN UT WOS:000075864100066 PM 9733871 ER PT J AU Wolgemuth, KS Kamhi, AG Lee, RF AF Wolgemuth, KS Kamhi, AG Lee, RF TI Metaphor performance in children with hearing impairment SO LANGUAGE SPEECH AND HEARING SERVICES IN SCHOOLS LA English DT Article DE hearing loss; children; figurative language; metaphor ID LEARNING-DISABILITIES; FIGURATIVE LANGUAGE; COMPREHENSION; IDIOMS; DEAF; CONSERVATION; STUDENTS AB Metaphor comprehension and use were evaluated in children with hearing impairment (HI) who performed within normal age limits on norm-referenced measures of language. Participants were 13 children with mild-to-moderate sensorineural hearing loss and 12 children with normal hearing and normal development (10:0 to 15:7 years:months). Three verbal metaphor tasks (comprehension, preference, and completion) and one visual metaphor task, the Metaphor Triads Task (MTT), were administered. No significant group differences were found on any of the tasks. Both groups exhibited the same metaphor competence and response patterns on the four tasks. These findings add to a growing body of literature showing that a significant number of children with mild-to-moderate HI have age-appropriate language abilities. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. Univ Memphis, Memphis, TN 38152 USA. Bodine Sch, Memphis, TN USA. RP Wolgemuth, KS (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 27 TC 8 Z9 9 U1 0 U2 5 PU AMER SPEECH-LANGUAGE-HEARING ASSOC PI ROCKVILLE PA 10801 ROCKVILLE PIKE, ROCKVILLE, MD 20852-3279 USA SN 0161-1461 J9 LANG SPEECH HEAR SER JI Lang. Speech Hear. Serv. Sch. PD OCT PY 1998 VL 29 IS 4 BP 216 EP 231 PG 16 WC Audiology & Speech-Language Pathology; Linguistics; Rehabilitation SC Audiology & Speech-Language Pathology; Linguistics; Rehabilitation GA 132HG UT WOS:000076623800004 PM 27764374 ER PT J AU Deschamps, JR George, C Flippen-Anderson, JL AF Deschamps, JR George, C Flippen-Anderson, JL TI The relationship between structure and activity among opioid peptides SO LETTERS IN PEPTIDE SCIENCE LA English DT Article DE enkephalin; neuropeptide; pharmacophore; X-ray diffraction ID X-RAY-DIFFRACTION; CRYSTAL-STRUCTURE; HIGHLY POTENT; H-1-NMR DATA; BETA-SHEET; RECEPTOR; CONFORMATION; ENKEPHALIN; ENKEPHALIN; ENKEPHALIN AB Since the discovery and isolation of the endogenous opioid peptides Leu- and Met-enkephalin, structural studies have been focused on deducing the bioactive conformation of the peptide ligands. Theoretically, Linear peptides can have many different backbone conformations, yet early X-ray studies on enkephalin and its analogues showed only two different backbone conformations: extended and single B-bend. More recent reports include a third conformation for Leu-enkephalin and constrained opioid peptides from two 'new' classes (i.e. cyclic and 'aromatic' peptides). In this report the relationship between solid-state X-ray structure and opioid peptide activity is examined. The N-terminal amine nitrogen and the two aromatic rings have previously been identified as structural features important to the biological activity of opioid peptides. From X-ray studies we find that the distances between the centroids of the aromatic rings, and between the N-terminal amine nitrogen and the centroid of the phenylalanine ring, vary over a large range. There is a discernible relationship, however, between the separation of the two rings and their orientation that correlates with activity. C1 USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. OI Deschamps, Jeffrey/0000-0001-5845-0010 NR 32 TC 3 Z9 3 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0929-5666 J9 LETT PEPT SCI JI Lett. Pept. Sci. PD OCT PY 1998 VL 5 IS 5-6 BP 337 EP 340 PG 4 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 132CQ UT WOS:000076612800006 ER PT J AU Jung, WY Suk, BC Min, GH Lee, YK AF Jung, WY Suk, BC Min, GH Lee, YK TI Sedimentary structure and origin of a mud-cored pseudo-tidal sand ridge, eastern Yellow Sea, Korea SO MARINE GEOLOGY LA English DT Article DE sedimentary structure; subbottom profiles; piston cores; tidal mud tongue; eastern Yellow Sea ID FACIES MODEL; STRATIGRAPHY; ESTUARY AB Using high-resolution seismic profiles, sidescan sonar images, and piston cores, we have examined an elongate ridge located off the Tae-An Peninsula of Korea in the eastern Yellow Sea. This ridge, 50 km long, 30 m high, and up to 12 km wide, is one of many similar longitudinal ones which are approximately parallel to the direction (NE-SW) of strong tidal currents. Bathymetric profiles across the ridge are all asymmetric: the eastern ridge flank is narrow and dips steeply towards the adjoining rocky valley. Below the eastern ridge flank, less steeply sloping subbottom reflectors are truncated by a seafloor-parallel erosion surface on which is draped a 45-cm-thick unit of muddy sand. A piston core taken here indicates that the subbottom reflectors are due to interlayered coarse sediments. The more gently sloping western ridge flank contains sand waves (ca. 100 m wavelength, ENE-WSW trend) on which megaripples (10-15 m wavelength, WNW-ESE trend) are superimposed, indicating recent bottom current activity. in particular the reflectors beneath the westernmost ridge show westward progradation over an acoustically transparent unit of thin sand sheets. However, subbottom profiles collected over the ridge crest do not show conspicuous reflectors. Only a few discontinuous, faint reflectors are observed. The lack of conspicuous reflectors below the ridge crest area may reflect more thorough bottom-current-generated sediment homogenization as well as poor penetration of acoustic energy; due to the current-scoured/rippled seafloor. We interpret the ridge as an early Holocene tidal mud tongue blanketed by recently reworked relict (palimpsest) sands. The 'pseudo-tidal sand ridge' has prograded westward. The fine-mud tongue sediments might have been derived mostly from the Korean Peninsula via the Han River at a time when sea level was lower than present. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Marine Geosci Div, Washington, DC 20375 USA. Korea Ocean Res & Dev Inst, Marine Geol & Geophys Div, Ansan, South Korea. Korea Inst Geol Min & Mat, Petr & Marine Resources Div, Taejon, South Korea. RP Jung, WY (reprint author), USN, Res Lab, Marine Geosci Div, Washington, DC 20375 USA. NR 33 TC 18 Z9 22 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0025-3227 J9 MAR GEOL JI Mar. Geol. PD OCT PY 1998 VL 151 IS 1-4 BP 73 EP 88 DI 10.1016/S0025-3227(98)00058-9 PG 16 WC Geosciences, Multidisciplinary; Oceanography SC Geology; Oceanography GA 138ZK UT WOS:000077002800004 ER PT J AU Vogt, PR Jung, WY Brozena, J AF Vogt, PR Jung, WY Brozena, J TI Arctic margin gravity highs: Deeper meaning for sediment depocenters? SO MARINE GEOPHYSICAL RESEARCH LA English DT Article DE Arctic; continental margin; gravity anomalies; mid-plate seismicity; sediment depocenters ID CONTINENT-OCEAN TRANSITION; NORWEGIAN GREENLAND SEA; CRUSTAL STRUCTURE; HAWAIIAN-ISLANDS; ANOMALIES; FLEXURE; VELOCITY; LITHOSPHERE; MORPHOLOGY; EVOLUTION AB Morphologic, gravity, and seismic reflection/refraction data from ca. 10,000 km of Arctic passive continental margins suggest that the numerous oval free-air gravity anomalies, their +50-150 mGal extrema typically located just landward of shelf breaks, are caused by combinations of rapidly deposited Plio-Pleistocene glacial marine sediment loads, older post-breakup sediments, and perhaps causally related density anomalies (mascons) in the underlying oceanic crust. Dispersed seismicity associated with some gravity highs may reflect ongoing brittle, flexural adjustment to the loads. Multi-channel-seismic-controlled depocenter models for several prominent highs (including the Hornsund gravity high re-examined here) suggest that sediments alone do not suffice to explain the gravity highs, unless depocenter seismic velocities have been significantly underestimated. A flexural backstripping model for the Hornsund anomaly only roughly replicates observed gravity. Subjacent 'mascons', if present below some depocenters, may be caused by (1) anomalous subsidence of initially formed dense/thin crust; (2) depocenter blanketing of early-formed crust, mitigating hydrothermal fracturing and related density reduction; or (3) metastable phase transitions, converting basalt/gabbro to denser phases (Neugebauer-Spohn hypothesis), while cracks close or fill under the increased pressures and temperatures. C1 USN, Res Lab, Marine Geosci Div, Washington, DC 20375 USA. RP Vogt, PR (reprint author), USN, Res Lab, Marine Geosci Div, Washington, DC 20375 USA. NR 65 TC 19 Z9 19 U1 2 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0025-3235 J9 MAR GEOPHYS RES JI Mar. Geophys. Res. PD OCT PY 1998 VL 20 IS 5 BP 459 EP 477 DI 10.1023/A:1004775228851 PG 19 WC Geochemistry & Geophysics; Oceanography SC Geochemistry & Geophysics; Oceanography GA 268FD UT WOS:000084402900004 ER PT J AU Glesener, JW Natishan, PM O'Grady, WE Aiken, J Morrish, AA AF Glesener, JW Natishan, PM O'Grady, WE Aiken, J Morrish, AA TI Fabrication of a high surface area boron-doped diamond coated tungsten mesh for electrochemical applications SO MATERIALS LETTERS LA English DT Article DE boron-doped diamond; electrochemical applications; high surface area electrode; chlorine production ID THIN-FILM ELECTRODES AB A tungsten mesh coated with boron-doped diamond was fabricated for use in electrochemical applications. Raman spectroscopy was used to verify that coating was diamond and scanning electron microscopy (SEM) confirmed that the mesh was completely coated. Electrochemical testing in a 0.1 M NaCl solution showed that chloride could be oxidized to chlorine and subsequently reduced. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Naval Res Lab, Washington, DC USA. Litton Electroopt, Garland, TX USA. Pioneer Chlor Alkali, Tacoma, WA USA. DARPA, Arlington, VA USA. RP Natishan, PM (reprint author), Naval Res Lab, Washington, DC USA. NR 12 TC 5 Z9 5 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-577X J9 MATER LETT JI Mater. Lett. PD OCT PY 1998 VL 37 IS 3 BP 138 EP 142 DI 10.1016/S0167-577X(98)00083-4 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 132QY UT WOS:000076642100007 ER PT J AU Bharti, V Zhao, XZ Zhang, QM Romotowski, T Tito, F Ting, R AF Bharti, V Zhao, XZ Zhang, QM Romotowski, T Tito, F Ting, R TI Ultrahigh field induced strain and polarization response in electron irradiated poly(vinylidene fluoride-trifluoroethylene) copolymer SO MATERIALS RESEARCH INNOVATIONS LA English DT Article DE polymers; PVDF-TrFE; electron irradiation; dielectric constant; Vogel-Fulcher law; strain; polarization; electrostriction; elastic modulus; elastic energy density ID VINYLIDENE FLUORIDE; RELAXOR FERROELECTRICS; TRANSITION; CRYSTALS AB The influence of electron dosage on the field induced strain, dielectric constant, and polarization response has been investigated in electron irradiated poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) 50/50 copolymer. It was found that under suitable electron dosage an ultrahigh electrostrictive strain can be achieved. Interestingly, material after irradiation exhibits many features resembling those of relaxer ferroelectrics, suggesting that the electron irradiation breaks up the coherent polarization domain in normal ferroelectric P(VDF-TrFE) copolymer into nano-polar regions that transform the material into a relaxer ferroelectric. In addition, many of the material properties including the field induced polarization, the electrostrictive strain, and elastic modulus exhibit irregular change (non-monotonical) with electron dosage, indicating a complex relation among the crosslinking density, crystallinity, crystallite size, and molecular conformation in determining the material responses. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. USN, Undersea Warfare Ctr, Newport, RI 02841 USA. Univ Cent Florida, Dept Chem, Orlando, FL 32816 USA. RP Zhang, QM (reprint author), Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. NR 25 TC 47 Z9 47 U1 1 U2 22 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1432-8917 J9 MATER RES INNOV JI Mater. Res. Innov. PD OCT PY 1998 VL 2 IS 2 BP 57 EP 63 DI 10.1007/s100190050063 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 133BG UT WOS:000076666100001 ER PT J AU Seely, JF Boyer, CN Holland, GE AF Seely, JF Boyer, CN Holland, GE TI Dual-energy bone densitometry using a single 100 ns x-ray pulse SO MEDICAL PHYSICS LA English DT Article DE dual-energy imaging; x-ray absorptiometry; bone densitometry; bone mineral ID COMPUTED RADIOGRAPHY; DIGITAL RADIOGRAPHY; CHEST RADIOGRAPHY; ABSORPTIOMETRY; DETECTOR; MAMMOGRAPHY; SPINE; DENSITY; SYSTEM; LUNAR AB A pulsed, portable hard x-ray source has been developed for medical imaging and flash x-ray absorptiometry. The source is powered by a Marx generator that drives a field emission x-ray tube which produces a 30-300 keV x-ray pulse of 100 ns duration. The x-ray fluence has dual-energy properties. The x-ray energy is relatively high early in the pulse and lower later in the pulse. The feasibility of using a single x-ray pulse for precision bone densitometry was analyzed. A computer simulation model was developed for the x-ray source, the filtration that enhances the dual-energy distribution, the absorption of the energy distribution by bone mineral and soft tissue, and the dual-energy detection system. It is feasible to determine the bone mineral density (BMD) of axial sites such as the lumbar spine and proximal femur with 2% precision over an area that is 15-20 mm in size, depending on the bone mineral and soft tissue thicknesses. An algorithm for determining the absolute BMD, to an accuracy of 2%, using a Plexiglas(TM)/TiO2 calibration phantom is discussed. At a distance of 50 cm from the source, the patient exposure is 3.7 mR. The average absorbed bone and tissue doses are 0.6 and 4.3 mrem, respectively. Factors that facilitate diagnostic measurements in clinical settings are the short patient observation time and the portability of the x-ray source. (C) 1998 American Association of Physicists in Medicine. [S0094-2405(98)00810-4]. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Space Res Assoc, Washington, DC 20024 USA. Sachs Freeman Associates Inc, Landover, MD 20785 USA. RP Seely, JF (reprint author), USN, Res Lab, Code 7674, Washington, DC 20375 USA. NR 33 TC 3 Z9 4 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD OCT PY 1998 VL 25 IS 10 BP 2027 EP 2036 DI 10.1118/1.598367 PG 10 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 129FE UT WOS:000076452500028 PM 9800712 ER PT J AU Keck, JW Kiser, WR AF Keck, JW Kiser, WR TI HAPR questioned SO MILITARY MEDICINE LA English DT Letter C1 USN Hosp, Dept Family Practice, Jacksonville, FL 32214 USA. RP Keck, JW (reprint author), USN Hosp, Dept Family Practice, Jacksonville, FL 32214 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD OCT PY 1998 VL 163 IS 10 BP V EP V PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA 130AJ UT WOS:000076496600002 ER PT J AU Kuo, HC Williams, RT AF Kuo, HC Williams, RT TI Scale-dependent accuracy in regional spectral methods SO MONTHLY WEATHER REVIEW LA English DT Article ID LIMITED-AREA MODEL; BOUNDARY-CONDITIONS; EQUATION AB The accuracy of a numerical model is often scale dependent. Large spatial-scale phenomena are expected to be numerically solved with better accuracy, regardless of whether the discretization is spectral, finite difference, or finite element. The purpose of this article is to discuss the scale-dependent accuracy associated with the regional spectral model variables expanded by sine-cosine series. In particular, the scale-dependent accuracy in the Chebyshev-tau, finite difference, and sinusoidal- or polynomial-subtracted sine-cosine expansion methods is considered. With the simplest examples, it is demonstrated that regional spectral models may possess an unusual scale-dependent accuracy. Namely, the numerical accuracy associated with large-spatial-scale phenomena may be worse than the numerical accuracy associated with small-spatial-scale phenomena. This unusual scale-dependent accuracy stems from the higher derivatives of basic-state subtraction functions, which are not periodic. The discontinuity is felt mostly by phenomena with large spatial scale. The derivative discontinuity not only causes the slow convergence of the expanded Fourier series (Gibbs phenomenon) but also results in the unusual scale-dependent numerical accuracy. The unusual scale-dependent accuracy allows large-spatial-scale phenomena in the model perturbation fields to be solved less accurately. C1 USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. Natl Taiwan Univ, Dept Atmospher Sci, Taipei 10764, Taiwan. RP Williams, RT (reprint author), USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. EM williart@met.nps.navy.mil OI KUO, HUNG-CHI/0000-0001-9102-5104 NR 17 TC 5 Z9 5 U1 0 U2 0 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 OCT PY 1998 VL 126 IS 10 BP 2640 EP 2647 DI 10.1175/1520-0493(1998)126<2640:SDAIRS>2.0.CO;2 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 126RF UT WOS:000076306400006 ER PT J AU Chang, CP Hou, SC Kuo, HC Chen, GTJ AF Chang, CP Hou, SC Kuo, HC Chen, GTJ TI The development of an intense East Asian summer monsoon disturbance with strong vertical coupling SO MONTHLY WEATHER REVIEW LA English DT Article ID TIBETAN PLATEAU; MESOSCALE VORTEX; HEAVY RAIN; CYCLOGENESIS AB The East Asian summer monsoon (Mei-yu) disturbance of 17-25 June 1992 was the most intense 850-hPa low center of such systems during a 7-yr period. Due to the moisture fluxes associated with the southwesterlies from the warm tropical oceans, diabatic heating has generally been considered the main energy source of these heavy-precipitation disturbances as they propagate eastward from the eastern flank of the Tibetan Plateau across southeastern China and move into the East China Sea. In this study piecewise potential vorticity inversion is used to analyze the physical mechanisms of this intense case, particularly the possible roles of midlatitude baroclinic processes in its development and evolution. The development of the low-level vortex involved the coupling with two upper-level disturbances, one at 500 hPa that also originated from the eastern flank of the Tibetan Plateau, and another at 300 hPa. Both disturbances appeared later than and upstream of the low-level vortex. Faster eastward movements allowed them to catch up with the low-level vortex and led to a strong vertical coupling and deep tropopause folding. Initially, diabatic heating was the dominant mechanism for the low-level vortex while the tropopause process opposed it. Both mechanisms supported the 500-hPa disturbance, and tropopause folding was the dominant mechanism for the 300-hPa disturbance. As the vertical coupling developed, the tropopause process reversed its earlier role in the low-level disturbance and contributed to its development. Boundary layer and adiabatic effects also became contributive as the disturbance moved out of eastern China to the oceanic region. The vertical coupling of the three disturbances was a major factor in the development. The timing and position of the middle-tropospheric disturbance was critical in bridging the upper- and lower-level disturbances and a deep tropopause folding. This midlatitude-originated process compounded the diabatic heating effect that was sustained by tropical moist air, leading to the strong intensification. C1 USN, Postgrad Sch, Dept Meteorol, MR Cp, Monterey, CA 93943 USA. Natl Taiwan Univ, Dept Atmospher Sci, Taipei 10764, Taiwan. RP Chang, CP (reprint author), USN, Postgrad Sch, Dept Meteorol, MR Cp, 589 Dyer Rd,Room 254, Monterey, CA 93943 USA. NR 17 TC 28 Z9 33 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 OCT PY 1998 VL 126 IS 10 BP 2692 EP 2712 DI 10.1175/1520-0493(1998)126<2692:TDOAIE>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 126RF UT WOS:000076306400009 ER PT J AU Piestrup, MA Powell, MW Mrowka, S Cremer, JT Lombardo, LW Chase, MB Snyder, D Rietdyk, H Maruyama, XK AF Piestrup, MA Powell, MW Mrowka, S Cremer, JT Lombardo, LW Chase, MB Snyder, D Rietdyk, H Maruyama, XK TI A transition radiation source with a grazing angle optic for step and scan lithography SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 3rd International Symposium on Radiation from Relativistic Electrons in Periodic Structures (RREPS 97) CY SEP, 1997 CL NUCLEAR PHYSICS INST, TOMSK POLYTECHN UNIV, TOMSK, RUSSIA HO NUCLEAR PHYSICS INST, TOMSK POLYTECHN UNIV DE X-ray lithography; integrated circuits; transition radiation; X-ray optics ID X-RAY SOURCE AB Using a grazing angle mirror, the collection and collimation of transition radiation into a slit pattern that can be scanned across an image plane for X-ray dose uniformity is demonstrated. An Au-coated grazing-angle optic was used to focus transition radiation into a rectangular or slit pattern (7 mm x 16 mm) in the image plane at 631 mm from the optic and 881 mm from the transition radiator. Intensity variation across the longitudinal direction (approximate to 10 mm) of the slit was less than +/-5%. The grazing angle optic with a transition radiator can be used for step and scan lithography for obtaining circuit resolution patterns below 0.1 mu m. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Adelphi Technol Inc, Palo Alto, CA 94306 USA. USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. RP Piestrup, MA (reprint author), Adelphi Technol Inc, 2181 Pk Blvd, Palo Alto, CA 94306 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD OCT PY 1998 VL 145 IS 1-2 BP 230 EP 235 DI 10.1016/S0168-583X(98)00287-0 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 132TX UT WOS:000076647100036 ER PT J AU Forsnes, EV Heaton, JO Bowen, E AF Forsnes, EV Heaton, JO Bowen, E TI Intrauterine Listeria infection of the nonpresenting twin SO OBSTETRICS AND GYNECOLOGY LA English DT Article C1 USN Hosp, Dept Obstet & Gynecol, Camp Lejeune, NC 28542 USA. USN, Med Ctr, Dept Obstet & Gynecol, Portsmouth, VA USA. RP Forsnes, EV (reprint author), USN Hosp, Dept Obstet & Gynecol, Camp Lejeune, NC 28542 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0029-7844 J9 OBSTET GYNECOL JI Obstet. Gynecol. PD OCT PY 1998 VL 92 IS 4 SU S BP 715 EP 715 DI 10.1016/S0029-7844(98)00236-1 PN 2 PG 1 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 124BF UT WOS:000076159900038 PM 9764682 ER PT J AU Regillo, CD Blade, KA Custis, PH O'Connell, SR AF Regillo, CD Blade, KA Custis, PH O'Connell, SR TI Evaluating persistent and recurrent choroidal neovascularization - The role of indocyanine green angiography SO OPHTHALMOLOGY LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Academy-of-Ophthalmology CY OCT 29, 1997 CL SAN FRANCISCO, CALIFORNIA SP Amer Acad Ophthalmol ID MACULAR DEGENERATION; SUBRETINAL NEOVASCULARIZATION; VIDEOANGIOGRAPHY AB Objective: To evaluate the clinical utility of routinely using indocyanine green angiography (ICGA) with fluorescein angiography (FA) in detecting persistent or recurrent choroidal neovascularization (CNV). Design: Prospective, consecutive case series. Participants: Twenty-four eyes of 21 patients with exudative age-related macular degeneration (AMD) that had conventional laser treatment for CNV were examined. Intervention: Fluorescein angiography and ICGA were performed together on ail eligible eyes at the first post-treatment visit and all subsequent follow-up visits in which persistent or recurrent CNV was suspected clinically. Main Outcome Measures: Choroidal neovascularization detection and delineation by each angiographic technique were measured. Results: Of the 54 FA-ICGA study pairs performed over a 20-month investigation period, FA showed well-defined, ill-defined, and no CNV in IO (19%), 19 (35%), and 25 (46%) eyes, respectively. Indocyanine green angiography had a high concordance rate at 70% and 88% when persistent or recurrent CNV was well-defined and absent, respectively, on FA and rarely added additional, clinically useful information in these settings, particularly in the former presentation. Of the 29 eyes that showed some evidence of CNV by FA, the neovascular complex was ill-defined in 19 (66%) eyes. When CNV was ill-defined by FA, the corresponding ICGA showed well-defined CNV in 9 (47%) of 19 eyes, in 5 of which the CNV was nonsubfoveal in location. Conclusions: Persistent or recurrent CNV in AMD was frequently ill-defined by FA, Indocyanine green angiography was a valuable adjunct to FA by better delineating CNV in this specific setting. However, ICGA was not useful when the post-treatment FA showed well-defined CNV. Furthermore, ICGA was not helpful when the first post-treatment FA was negative and there were no ophthalmoscopic signs of exudation. C1 USN, Med Ctr, Retina Serv, Dept Ophthalmol, San Diego, CA 92152 USA. RP Regillo, CD (reprint author), Wills Eye Hosp, Retina Serv, 900 Walnut St, Philadelphia, PA 19107 USA. NR 26 TC 10 Z9 11 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0161-6420 J9 OPHTHALMOLOGY JI Ophthalmology PD OCT PY 1998 VL 105 IS 10 BP 1821 EP 1826 DI 10.1016/S0161-6420(98)91022-3 PG 6 WC Ophthalmology SC Ophthalmology GA 127JW UT WOS:000076348300023 PM 9787349 ER PT J AU Kang, JU Aitchison, JS Stegeman, GI Akhmediev, N AF Kang, JU Aitchison, JS Stegeman, GI Akhmediev, N TI One-dimensional spatial solitons in AlGaAs waveguides SO OPTICAL AND QUANTUM ELECTRONICS LA English DT Article ID POWER-DEPENDENT POLARIZATION; BIREFRINGENT OPTICAL FIBERS; PLANAR WAVE-GUIDES; HALF BAND-GAP; PULSE-PROPAGATION; VECTOR SOLITONS; SOLITARY WAVES; ABSORPTION; DYNAMICS; ROBUSTNESS AB We present experimental results on one-dimensional (1-D) spatial solitons in AlGaAs waveguides. Three distinct types of spatial solitons have been observed: namely the fundamental soliton, the Manakov soliton, and the vector soliton. The fundamental soliton is the simplest form of 1-D soliton which consists of a single polarization. The properties of waveguiding and 'robustness' are experimentally studied. Vector solitons which result from the complex interplay between the two orthogonally polarized beams due to self-phase modulation, cross-phase modulation, and four-wave mixing effects are studied. The complex beam dynamics and polarization behaviour of the vector solitons are experimentally studied. Manakov solitons which are a special case of the vector soliton exist when the ratio between the self-to-cross-phase modulation is one and the four-wave mixing effects becomes zero are demonstrated experimentally and the basic properties discussed. Finally, some soliton interactions such as trapping and dragging are reported and possible applications of soliton interactions are discussed. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Univ Glasgow, Dept Elect & Elect Engn, Glasgow G12 8LQQ, Lanark, Scotland. Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Orlando, FL 32826 USA. Australian Natl Univ, Ctr Opt Sci, Canberra, ACT 0200, Australia. RP USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RI Kang, Jin/A-3228-2010 NR 48 TC 9 Z9 9 U1 0 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0306-8919 EI 1572-817X J9 OPT QUANT ELECTRON JI Opt. Quantum Electron. PD OCT PY 1998 VL 30 IS 7-10 BP 649 EP 671 DI 10.1023/A:1006935801045 PG 23 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA 159FB UT WOS:000078160300007 ER PT J AU Statman, D Lombardi, JC Shensky, WM Gilbreath, GC AF Statman, D Lombardi, JC Shensky, WM Gilbreath, GC TI Temporal response of barium titanate to slowly oscillating signals SO OPTICS COMMUNICATIONS LA English DT Article ID PHOTOREFRACTIVE MATERIALS AB Theoretical and experimental results are presented which demonstrate that slowly oscillating signals experience a temporal delay in photorefractive two beam coupling experiments. This delay corresponds to the response time of the signal. It is determined to be dependent on the frequency of the oscillating input signal. In the limit of low frequencies, the response time is given by the product of the space charge field response time and the gain. As the frequency increases, the response time decreases. For high enough frequencies, response times faster than the space charge field response time are predicted and experimentally observed. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Allegheny Coll, Dept Phys, Meadville, PA 16335 USA. USN, Res Lab, Ctr Space Technol, Washington, DC 20375 USA. RP Statman, D (reprint author), Allegheny Coll, Dept Phys, Meadville, PA 16335 USA. RI Shensky, William/J-7012-2014 NR 16 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD OCT 1 PY 1998 VL 155 IS 1-3 BP 223 EP 230 DI 10.1016/S0030-4018(98)00277-6 PG 8 WC Optics SC Optics GA 127RH UT WOS:000076364000031 ER PT J AU Goldberg, L Koplow, J Lancaster, DG Curl, RF Tittel, FK AF Goldberg, L Koplow, J Lancaster, DG Curl, RF Tittel, FK TI Mid-infrared difference-frequency generation source pumped by a 1.1-1.5-mu m dual-wavelength fiber amplifier for trace-gas detection SO OPTICS LETTERS LA English DT Article AB Continuous-wave mid-infrared radiation near 3.5 mu m is generated by difference-frequency mixing of the output of a compact 1.1-1.5-mu m dual-wavelength fiber amplifier in periodically poled LiNbO3. The diode side-pumped amplifier is constructed with double-cladding Yb-doped fiber followed by single-mode Er/Yb codoped fiber. Output powers of as much as 11 mu W at 3.4 mu m are obtained, and spectroscopic detection of CH4 and H2CO is demonstrated. (C) 1998 Optical Society of America. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Rice Univ, Rice Quantum Inst, Houston, TX 77005 USA. RP Goldberg, L (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RI Lancaster, David/J-4215-2016 OI Lancaster, David/0000-0002-1299-8600 NR 7 TC 28 Z9 29 U1 1 U2 2 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 OCT 1 PY 1998 VL 23 IS 19 BP 1517 EP 1519 DI 10.1364/OL.23.001517 PG 3 WC Optics SC Optics GA 124AZ UT WOS:000076159300007 PM 11763099 ER PT J AU Elban, WL Armstrong, RW Russell, TP AF Elban, WL Armstrong, RW Russell, TP TI Plasticity/interfacial energy influences on combustion-driven cracking of RDX energetic crystals SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID SINGLE-CRYSTALS; IGNITION AB The hardness stress-strain response of cyclotrimethylenetrinitramine (RDX) crystals gives emphasis to a rather narrow difference in plasticity and cracking behaviour that, in the latter case, is reasoned to be significantly enhanced because of crack surface energy lowering by melting during combustion. C1 Loyola Coll, Baltimore, MD 21210 USA. Univ Maryland, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. RP Elban, WL (reprint author), Loyola Coll, Baltimore, MD 21210 USA. NR 16 TC 4 Z9 4 U1 0 U2 3 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD OCT PY 1998 VL 78 IS 4 BP 907 EP 912 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 124MF UT WOS:000076185600008 ER PT J AU Misra, S Gatt, R Schmauder, T Chubukov, AV Onellion, M Zacchigna, M Vobornik, I Zwick, F Grioni, M Margaritondo, G Quitmann, C Kendziora, C AF Misra, S Gatt, R Schmauder, T Chubukov, AV Onellion, M Zacchigna, M Vobornik, I Zwick, F Grioni, M Margaritondo, G Quitmann, C Kendziora, C TI Evolution of the quasiparticle spectral function in cuprates SO PHYSICAL REVIEW B LA English DT Article ID ANGLE-RESOLVED PHOTOEMISSION; SUPERCONDUCTORS; BI2SR2CACU2O8+DELTA; STATE AB We analyzed photoemission data for several doping levels of the Bi2Sr2CaCu2O8+x compounds, ranging from overdoped to underdoped. We show that the high frequency part of the spectra near (0,pi) can be described by Fermi liquid theory in the overdoped regime, but exhibits a non-Fermi liquid behavior in the underdoped regime. We further demonstrate that this behavior fits reasonably well to a 1/root omega behavior suggested for systems with strong spin fluctuations. [S0163-1829(98)50338-4]. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Ecole Polytech Fed Lausanne, CH-1015 Lausanne, Switzerland. Univ Dortmund, D-44221 Dortmund, Germany. USN, Res Lab, Washington, DC 20375 USA. RP Misra, S (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. EM onellion@comb.physics.wisc.edu RI Quitmann, Christoph/A-7047-2008; Margaritondo, Giorgio/B-1367-2008; Vobornik, Ivana/B-9463-2015 NR 17 TC 3 Z9 3 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD OCT 1 PY 1998 VL 58 IS 14 BP R8905 EP R8908 DI 10.1103/PhysRevB.58.R8905 PG 4 WC Physics, Condensed Matter SC Physics GA 129WH UT WOS:000076486700011 ER PT J AU Sanford, TWL Mock, RC Spielman, RB Peterson, DL Mosher, D Roderick, NF AF Sanford, TWL Mock, RC Spielman, RB Peterson, DL Mosher, D Roderick, NF TI Increased x-ray power generated from low-mass large-number aluminum-wire-array Z-pinch implosions SO PHYSICS OF PLASMAS LA English DT Article ID K-SHELL EMISSION; PLASMAS; DIAGNOSTICS; OPTIMIZATION; OUTPUT AB A Saturn accelerator study of annular, aluminum-wire-array, Z-pinch implosions in the calculated high-wire-number plasma-shell regime [Phys. Rev. Lett. 77, 5063 (1996)] shows that a factor of 2 decrease in pulse width and an associated doubling of the total radiated x- ray power occurs when the mass of 12 mm radius, 2 cm long array is reduced from above 1.9 mg to below 1.3 mg. The study utilized extensive time- and space-resolved measurements to characterize the implosion over the mass range 0.42-3.4 mg. Eulerian radiation-magnetohydrodynamic-code simulations in the r-z plane agree qualitatively with the measurements. They suggest that the pulse-width decrease with mass is due to the faster implosion velocity of the plasma shell relative to the growth of the shell thickness that arises from a two-stage development of the magnetic Rayleigh-Taylor instability. Over the bulk of the mass-range explored, the variation in K-shell (lines plus free-bound continuum) yield is in qualitative agreement with simple K-shell radiation-scaling models. These models indicate that the doubling of the measured K-shell yield, which also occurs for masses below 1.3 mg relative to masses above 1.9 mg, arises from increased plasma temperature. (C) 1998 American Institute of Physics. [S1070-664X(98)01410-4]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USN, Res Lab, Pulsed Power Phys Branch, Washington, DC 20375 USA. Univ New Mexico, Albuquerque, NM 87131 USA. RP Sanford, TWL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM twsanfo@sandia.gov NR 46 TC 43 Z9 49 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD OCT PY 1998 VL 5 IS 10 BP 3737 EP 3754 DI 10.1063/1.872984 PG 18 WC Physics, Fluids & Plasmas SC Physics GA 124PE UT WOS:000076190200034 ER PT J AU Sanford, TWL Mock, RC Spielman, RB Peterson, DL Mosher, D Roderick, NF AF Sanford, TWL Mock, RC Spielman, RB Peterson, DL Mosher, D Roderick, NF TI Symmetric aluminum-wire arrays generate high-quality Z pinches at large array radii SO PHYSICS OF PLASMAS LA English DT Article ID X-RAY-EMISSION; HIGH-POWER; DIAGNOSTICS; IMPLOSIONS; TEMPERATURE; DENSITY; PLASMAS; ENERGY AB A Saturn-accelerator study of annular, aluminum-wire array, Z-pinch implosions, in the calculated high-wire-number plasma-shell regime [Phys. Rev. Lett. 77, 5063 (1996)], shows that the radiated x-ray pulse width increases from about 4 nsec to about 7 nsec, when the radius of the array is increased from 8.75 to 20 mm at a fixed array mass of 0.6 mg. Eulerian radiation-magnetohydrodynamic code (E-RMHC) simulations in the r-z plane suggest that this pulse-width increase with radius is due to the faster growth of the shell thickness (that arises from a two-stage development in the magnetic Rayleigh-Taylor instability) relative to the increase in the shell implosion velocity. Over the array radii explored, the measured peak total x-ray power of similar to 40 TW and energy of similar to 325 kJ show little change outside of a +/-15% shot-to-shot fluctuation and are consistent with the E-RMHC simulations. Similarly, the measured peak K-shell (lines plus continuum) power of similar to 8 TW and energy of similar to 70 kJ show little change with radius. The minimal change in K-shell yield is in agreement with simple K-shell radiation scaling models that assume a fixed radial compression for all initial array radii. These results suggest that the improved uniformity provided by the large number of wires in the initial array reduces the disruptive effects of the Rayleigh-Taylor instability observed in small-wire-number imploding loads. (C) 1998 American Institute of Physics. [S1070-664X(98)01510-9]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USN, Res Lab, Pulsed Power Phys Branch, Washington, DC 20375 USA. Univ New Mexico, Albuquerque, NM 87131 USA. RP Sanford, TWL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 26 TC 17 Z9 19 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD OCT PY 1998 VL 5 IS 10 BP 3755 EP 3763 DI 10.1063/1.872985 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 124PE UT WOS:000076190200035 ER PT J AU Lappert, PW Lee, JW AF Lappert, PW Lee, JW TI Treatment of an isolated outer table frontal sinus fracture using endoscopic reduction and fixation SO PLASTIC AND RECONSTRUCTIVE SURGERY LA English DT Article ID FACIAL REJUVENATION C1 Natl Naval Med Ctr, Dept Plast & Reconstruct Surg, Portsmouth, VA 23708 USA. RP Lappert, PW (reprint author), Natl Naval Med Ctr, Dept Plast & Reconstruct Surg, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 13 TC 21 Z9 21 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0032-1052 J9 PLAST RECONSTR SURG JI Plast. Reconstr. Surg. PD OCT PY 1998 VL 102 IS 5 BP 1642 EP 1645 DI 10.1097/00006534-199810000-00050 PG 4 WC Surgery SC Surgery GA 126PL UT WOS:000076285500050 PM 9774026 ER PT J AU Storms, RL Roesli, JT Biggs, LJ Falby, JS Barham, PT Zyda, MJ AF Storms, RL Roesli, JT Biggs, LJ Falby, JS Barham, PT Zyda, MJ TI The NPSNET sound cube SO PRESENCE-TELEOPERATORS AND VIRTUAL ENVIRONMENTS LA English DT Article AB This paper describes the implementation of the sound system used to generate aural cues for use in the distributed virtual environment of NPSNET. This sound system is called the NPSNET-3D Sound Server. It is a MIDI-based loudspeaker system consisting of commercial, off-the-shelf equipment. This sound system currently generates 2-D aural cues via four speakers, but is designed for the potential generation of 3-D aural cues via a cube configuration of eight speakers. C1 USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. RP Zyda, MJ (reprint author), USN, Postgrad Sch, Dept Comp Sci, Code CS-ZK, Monterey, CA 93943 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU M I T PRESS PI CAMBRIDGE PA FIVE CAMBRIDGE CENTER, CAMBRIDGE, MA 02142 USA SN 1054-7460 J9 PRESENCE-TELEOP VIRT JI Presence-Teleoper. Virtual Env. PD OCT PY 1998 VL 7 IS 5 BP 503 EP 508 DI 10.1162/105474698565884 PG 6 WC Computer Science, Cybernetics; Computer Science, Software Engineering SC Computer Science GA 135BF UT WOS:000076779000006 ER PT J AU Graham, JR Abrams, M Bennett, C Carr, J Cook, K Dey, A Najita, J Wishnow, E AF Graham, JR Abrams, M Bennett, C Carr, J Cook, K Dey, A Najita, J Wishnow, E TI The performance and scientific rationale for an infrared imaging Fourier transform spectrograph on a large space telescope SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID HUBBLE DEEP FIELD; STAR-FORMATION HISTORY; K-BAND SURVEY; PLANETARY COMPANION; GALAXY COUNTS; SPECTROMETER; SPECTROSCOPY; REDUCTION; OBJECTS; ROCKET AB We describe a concept for an imaging spectrograph for a large orbiting observatory such as NASA's proposed Next Generation Space Telescope (NGST) based on an imaging Fourier transform spectrograph (IFTS). An IFTS has several important advantages that make it an ideal instrument to pursue the scientific objectives of NGST. We review the operation of an IFTS and make a quantitative evaluation of the signal-to-noise performance of such an instrument in the context of NGST. We consider the relationship between pixel size, spectral resolution, and diameter of the beam splitter for imaging and nonimaging Fourier transform spectrographs and give the condition required to maintain spectral modulation efficiency over the entire field of view. We give examples of scientific programs that could be performed with this facility. C1 Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. ITT Aerosp, Commun Div, Ft Wayne, IN 46801 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. USN, Res Lab, Washington, DC 20375 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Calif Berkeley, Space Sci Lab, Livermore, CA 94550 USA. RP Graham, JR (reprint author), Univ Calif Berkeley, Dept Astron, 601 Campbell Hall, Berkeley, CA 94720 USA. NR 53 TC 24 Z9 24 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD OCT PY 1998 VL 110 IS 752 BP 1205 EP 1215 DI 10.1086/316237 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 134LU UT WOS:000076745200008 ER PT J AU Raman, S Mohanty, UC Reddy, NC Alapaty, K Madala, RV AF Raman, S Mohanty, UC Reddy, NC Alapaty, K Madala, RV TI Numerical simulation of the sensitivity of summer monsoon circulation and rainfall over India to land surface processes SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE numerical simulation; summer monsoon; circulation; land surface; parameterization ID MESOSCALE CIRCULATIONS; BOUNDARY-LAYER; PARAMETERIZATION; SOIL; PRECIPITATION; VEGETATION; CONVECTION; MODELS AB The influence of soil moisture and vegetation variation on simulation of monsoon circulation and rainfall is investigated. For this purpose a simple land surface parameterization scheme is incorporated in a three-dimensional regional high resolution nested grid atmospheric model. Based on the land surface parameterization scheme, latent heat and sensible heat fluxes are explicitly estimated over the entire domain of the model. Two sensitivity studies are conducted; one with bare dry soil conditions (no latent heat flux from land surface) and the other with realistic representation of the land surface parameters such as soil moisture, vegetation cover and landuse patterns in the numerical simulation. The sensitivity of main monsoon features such as Somali jet, monsoon trough and tropical easterly jet to land surface processes are discussed. Results suggest the necessity of including a detailed land surface parameterization in the realistic short-range weather numerical predictions. An enhanced short-range prediction of hydrological cycle including precipitation was produced by the model, with land surface processes parameterized. This parameterization appears to simulate all the main circulation features associated with the summer monsoon in a realistic manner. C1 N Carolina State Univ, Dept Marine Earth & Atmospher Sci, Raleigh, NC 27695 USA. Indian Inst Technol, Ctr Atmospher Sci, New Delhi, India. USN, Res Lab, Washington, DC 20375 USA. RP Raman, S (reprint author), N Carolina State Univ, Dept Marine Earth & Atmospher Sci, Box 8208, Raleigh, NC 27695 USA. NR 23 TC 5 Z9 5 U1 1 U2 1 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0033-4553 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD OCT PY 1998 VL 152 IS 4 BP 781 EP 809 DI 10.1007/s000240050178 PG 29 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 147RY UT WOS:000077512700009 ER PT J AU Cai, W Chu, PC AF Cai, W Chu, PC TI Oceanic responses to gradual transitions of equator-to-pole temperature-gradients SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE thermohaline circulation; climate changes; multiple equilibrium; interdecadal oscillations; thermohaline ID MIXED BOUNDARY-CONDITIONS; GENERAL-CIRCULATION MODELS; ATMOSPHERIC CARBON-DIOXIDE; NORTH-ATLANTIC OCEAN; FRESH-WATER FLUX; THERMOHALINE CIRCULATION; PARAMETER SENSITIVITY; TRANSIENT-RESPONSE; SEA-ICE; SALINE CIRCULATION AB Responses of an ocean model to gradual transitions of equator-to-pole gradients show that several quasiequilibrium states within the thermally driven regime are generated under identical forcing conditions. These different states are associated with different patterns (the location and the penetration depth) of oceanic convection. Small changes in the thermal forcing conditions can push the system into an oscillatory regime. Once in this regime, oscillations appear to proceed as internal processes. One important implication of these results is that the present-day ocean climate may not recover fully if the atmospheric CO(2) level, after doubling, is lowered to the present-day level. C1 CSIRO, Div Atmospher Res, Aspendale, Vic 3195, Australia. USN, Postgrad Sch, Monterey, CA USA. RP Cai, W (reprint author), CSIRO, Div Atmospher Res, PMB1, Aspendale, Vic 3195, Australia. RI Cai, Wenju/C-2864-2012 NR 50 TC 3 Z9 3 U1 0 U2 1 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 OCT PY 1998 VL 124 IS 552 BP 2817 EP 2828 PN B PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 157HW UT WOS:000078052700013 ER PT J AU Meier, SR Tveekrem, JL Keski-Kuha, RAM AF Meier, SR Tveekrem, JL Keski-Kuha, RAM TI A far-ultraviolet contamination-irradiation facility for in situ reflectance measurements SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB In this article, a contamination-irradiation facility designed to measure contamination effects on far-ultraviolet optical surfaces is described. An innovative feature of the facility is the capability of depositing a contaminant, photopolymerizing the contaminant with far-ultraviolet light, and measuring the reflectance of the contaminated sample, all in situ. In addition to describing the facility, we present far-ultraviolet reflectance measurements for a contaminated mirror. (C) 1998 American Institute of Physics. [S0034-6748(98)04210-5]. C1 Hughes STX, Greenbelt, MD 20771 USA. NASA, Opt Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Meier, SR (reprint author), USN, Res Lab, Div Opt Sci, Code 5622, Washington, DC 20375 USA. NR 9 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD OCT PY 1998 VL 69 IS 10 BP 3642 EP 3644 DI 10.1063/1.1149152 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 128VX UT WOS:000076430000031 ER PT J AU Xu, Q AF Xu, Q TI Comments on "Tangent linear and adjoint of 'on-off' processes and their feasibility for use in 4-dimensional variational data assimilation" SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Letter ID PARAMETERIZED DISCONTINUITIES; GENERALIZED ADJOINT; PHYSICAL PROCESSES C1 USN, Res Lab, Monterey, CA 93943 USA. RP Xu, Q (reprint author), USN, Res Lab, Monterey, CA 93943 USA. NR 6 TC 5 Z9 7 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6495 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD OCT PY 1998 VL 50 IS 5 BP 653 EP 656 DI 10.1034/j.1600-0870.1998.t01-4-00006.x PG 4 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA 150UG UT WOS:000077683200006 ER PT J AU Pivacek, LE Ragno, G Cassidy, G Valeri, CR AF Pivacek, LE Ragno, G Cassidy, G Valeri, CR TI Viability, function and hemolysis of 42 day AS-1, AS-3 or AS-5 red cells following rejuvenation and cryopreservation SO TRANSFUSION LA English DT Meeting Abstract C1 Boston Univ, Sch Med, USN, Res Lab, Boston, MA 02215 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD OCT PY 1998 VL 38 IS 10 SU S MA S22 BP 11S EP 11S PG 1 WC Hematology SC Hematology GA 124FM UT WOS:000076171800043 ER PT J AU Pivacek, LE Ragno, G Cassidy, G White, JF Valeri, CR AF Pivacek, LE Ragno, G Cassidy, G White, JF Valeri, CR TI 24 hr posttransfusion survival, function and hemolysis of red blood cells stored at 4C for 56 days in AS-3. SO TRANSFUSION LA English DT Meeting Abstract C1 Boston Univ, Sch Med, USN, Blood Res Lab, Boston, MA 02215 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD OCT PY 1998 VL 38 IS 10 SU S MA S27 BP 12S EP 12S PG 1 WC Hematology SC Hematology GA 124FM UT WOS:000076171800048 ER PT J AU Pivacek, LE Ragno, G Cassidy, G Valeri, CR AF Pivacek, LE Ragno, G Cassidy, G Valeri, CR TI 24 hr posttransfusion survival and hemolysis in previously frozen red cells after storage at 4C for as long as 14 days in sodium chloride alone or sodium chloride supplemented with AS-1, AS-3 or AS-5. SO TRANSFUSION LA English DT Meeting Abstract C1 Boston Univ, Sch Med, USN, Blood Res Lab, Boston, MA 02215 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD OCT PY 1998 VL 38 IS 10 SU S MA S31 BP 13S EP 13S PG 1 WC Hematology SC Hematology GA 124FM UT WOS:000076171800052 ER PT J AU Valeri, CR Ragno, G MacGregor, H Barnard, MR AF Valeri, CR Ragno, G MacGregor, H Barnard, MR TI Survival of GPIb normal and GPIb reduced subpopulations of autologous cryopreserved baboon platelets. SO TRANSFUSION LA English DT Meeting Abstract C1 Univ Massachusetts, Med Ctr, Worcester, MA USA. Boston Univ, Sch Med, USN, Blood Res Lab, Boston, MA 02215 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD OCT PY 1998 VL 38 IS 10 SU S MA S32 BP 13S EP 13S PG 1 WC Hematology SC Hematology GA 124FM UT WOS:000076171800053 ER PT J AU Valeri, CR Ragno, G Pages, E Chammas, J Stacey, G AF Valeri, CR Ragno, G Pages, E Chammas, J Stacey, G TI A functionally closed, automated system to glycerolize and deglycerolize red cells. SO TRANSFUSION LA English DT Meeting Abstract C1 Boston Univ, Sch Med, USN, Blood Res Lab, Boston, MA 02215 USA. Haemonet Corp, Braintree, MA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD OCT PY 1998 VL 38 IS 10 SU S MA S41 BP 16S EP 16S PG 1 WC Hematology SC Hematology GA 124FM UT WOS:000076171800062 ER PT J AU Fahie, RL Leslie, SB Luban, NLC Rudolph, AS AF Fahie, RL Leslie, SB Luban, NLC Rudolph, AS TI A study of the effects of leukoreduction on blood units collected in CPD with the additive solution Optisol (R) (AS-5) using the pall BF4C leukoreduction filter. SO TRANSFUSION LA English DT Meeting Abstract C1 NRL, Washington, DC USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD OCT PY 1998 VL 38 IS 10 SU S MA S245 BP 67S EP 67S PG 1 WC Hematology SC Hematology GA 124FM UT WOS:000076171800265 ER PT J AU Pivacek, LE Ragno, G Cassidy, G Valeri, CR AF Pivacek, LE Ragno, G Cassidy, G Valeri, CR TI Restoration of in vivo red blood cell volume following two unit red cell apheresis. SO TRANSFUSION LA English DT Meeting Abstract C1 BU Sch Med, USN, Blood Res Lab, Boston, MA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD OCT PY 1998 VL 38 IS 10 SU S MA S306 BP 82S EP 82S PG 1 WC Hematology SC Hematology GA 124FM UT WOS:000076171800326 ER PT J AU Valeri, CR MacGregor, H Ragno, G Hechtman, HB Mercier, R Barnard, MR AF Valeri, CR MacGregor, H Ragno, G Hechtman, HB Mercier, R Barnard, MR TI Platelet-surface P-selectin, platelet-granulocyte heterotypic aggregates and plasma soluble P-selectin during plateletpheresis. SO TRANSFUSION LA English DT Meeting Abstract C1 Boston Univ, Sch Med, USN, Blood Res Lab, Boston, MA 02215 USA. Brigham & Womens Hosp, Boston, MA 02115 USA. Univ Massachusetts, Med Ctr, Worcester, MA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD OCT PY 1998 VL 38 IS 10 SU S MA S317 BP 85S EP 85S PG 1 WC Hematology SC Hematology GA 124FM UT WOS:000076171800337 ER PT J AU McKeown, MJ Makeig, S Brown, GG Jung, TP Kindermann, SS Bell, AJ Sejnowski, TJ AF McKeown, MJ Makeig, S Brown, GG Jung, TP Kindermann, SS Bell, AJ Sejnowski, TJ TI Modes or models: a critique on independent component analysis for fMRI - Response SO TRENDS IN COGNITIVE SCIENCES LA English DT Editorial Material C1 Duke Univ, Med Ctr, Durham, NC 27710 USA. Naval Hlth Res Ctr, San Diego, CA 92186 USA. Univ Calif San Diego, Sch Med, Dept Neurosci, La Jolla, CA 92093 USA. Univ Calif San Diego, Sch Med, Dept Psychiat, La Jolla, CA 92093 USA. Salk Inst Biol Studies, Howard Hughes Med Inst, Computat Neurobiol Lab, San Diego, CA 92186 USA. Univ Calif San Diego, Dept Biol, La Jolla, CA 92093 USA. RP McKeown, MJ (reprint author), Duke Univ, Med Ctr, 227D Bryan Res Bldg,Box 2900, Durham, NC 27710 USA. EM martin.mckeown@duke.edu NR 0 TC 11 Z9 13 U1 2 U2 3 PU ELSEVIER SCIENCE LONDON PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 1364-6613 J9 TRENDS COGN SCI JI TRENDS COGN. SCI. PD OCT PY 1998 VL 2 IS 10 BP 375 EP 375 PG 1 WC Behavioral Sciences; Neurosciences; Psychology, Experimental SC Behavioral Sciences; Neurosciences & Neurology; Psychology GA 171PN UT WOS:000078872700002 ER PT J AU Boroujerdi, A Uhlmann, J AF Boroujerdi, A Uhlmann, J TI An efficient algorithm for computing least cost paths with turn constraints SO INFORMATION PROCESSING LETTERS LA English DT Article DE Dijkstra's algorithm; shortest paths; least cost paths; range searching; routing; turn constraints; computational complexity AB An algorithm is presented for computing least cost paths under turn angle constraints. The approach is almost as efficient as Dijkstra's algorithm for unconstrained least cost paths. Specifically, if a graph representation of a two- or three-dimensional routing problem contains \V\ vertices and \E\ edges, then our algorithm scales as O(\E\ log \V\) versus the O(\V\ log \V\ + \E\) complexity for the most efficient implementation of Dijkstra's algorithm. This result is substantially better than O(\E\\V\) algorithms for the more general problem of routing with turn penalties, which cannot be applied to large scale graphs. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. RP Uhlmann, J (reprint author), USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. NR 4 TC 16 Z9 16 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0020-0190 J9 INFORM PROCESS LETT JI Inf. Process. Lett. PD SEP 30 PY 1998 VL 67 IS 6 BP 317 EP 321 DI 10.1016/S0020-0190(98)00134-3 PG 5 WC Computer Science, Information Systems SC Computer Science GA 129JG UT WOS:000076459600009 ER PT J AU Hubler, GK Cotell, CM Carosella, CA Schiestel, S AF Hubler, GK Cotell, CM Carosella, CA Schiestel, S TI Metastable materials formation by ion beam assisted deposition: application to metal clusters in ceramic matrices SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT Engineering Foundation Conference on the Modification of Ceramics and Semiconductors by Ion Bombardment CY MAY 19-23, 1997 CL IL CIOCCO, ITALY SP Engn Fdn DE collision cascade; ion beam assisted deposition; metal clusters in ceramics; beam assisted phase separation ID THIN-FILM DEPOSITION; NONLINEAR-OPTICAL PROPERTIES; ENERGY; IMPLANTATION; DEPENDENCE AB The collision cascade, the fundamental event in ion-solid interactions, is responsible for the beneficial effects on thin films deposited by low energy ion beam assisted deposition (IBAD) or by energetic ion assisted deposition processes in general. However, the fundamental implications of the marriage of collision cascades and film growth processes have yet to be fully realized. The first section of this paper reviews the effects of ion bombardment on film growth and reaches the conclusion that IBAD processing drives material synthesis parameter phase space into new regimes. Therefore, IBAD processing leads to microstructures far from equilibrium that are unattainable by other materials synthesis methods. The second part of this paper reviews an application of IBAD which tends to support the hypothesis that it is a distinct form of ion-solid interaction. It describes the production of unique metastable materials, demonstrated through deposition of metal nanoclusters in a dielectric matrix by means of beam assisted phase separation (BAPS), a term coined here to describe deposition of phase-separated multicomponent materials. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Surface Modificat Branch, Res Lab, Washington, DC 20375 USA. Univ Heidelberg, Heidelberg, Germany. RP Hubler, GK (reprint author), USN, Surface Modificat Branch, Res Lab, Washington, DC 20375 USA. EM graham.hubler@nrl.navy.mil NR 31 TC 4 Z9 4 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD SEP 30 PY 1998 VL 253 IS 1-2 BP 212 EP 220 DI 10.1016/S0921-5093(98)00729-1 PG 9 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 130LG UT WOS:000076521100026 ER PT J AU Henderson, DR AF Henderson, DR TI Opinion - Rehabilitating the supply side SO FORTUNE LA English DT Editorial Material C1 USN, Postgrad Sch, Washington, DC 20350 USA. RP Henderson, DR (reprint author), USN, Postgrad Sch, Washington, DC 20350 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU TIME INC PI NEW YORK PA TIME & LIFE BUILDING ROCKEFELLER CENTER, NEW YORK, NY 10020-1393 USA SN 0015-8259 J9 FORTUNE JI Fortune PD SEP 28 PY 1998 VL 138 IS 6 BP 64 EP + PG 2 WC Business SC Business & Economics GA 117XK UT WOS:000075807800019 ER PT J AU Bonadeo, NH Chen, G Gammon, D Katzer, DS Park, D Steel, DG AF Bonadeo, NH Chen, G Gammon, D Katzer, DS Park, D Steel, DG TI Nonlinear nano-optics: Probing one exciton at a time SO PHYSICAL REVIEW LETTERS LA English DT Article ID SEMICONDUCTOR QUANTUM DOTS; WELLS; GAAS; PHOTOLUMINESCENCE; BIEXCITONS AB Coherent nonlinear optical spectroscopy of individual excitons in GaAs quantum dots is demonstrated and shows strong similarities with atoms in their coherent optical interaction, unlike higher dimensional heterostructures. The nonlinear response is dominated by an incoherent contribution (saturation) and a coherent contribution (population pulsations) of the single dot and compares well with present theory. The data shows that energy relaxation and dephasing rates are comparable, reflecting the absence of significant pure dephasing, and also demonstrate the presence of interdot energy transfer. [S0031-9007(98)07287-1]. C1 Univ Michigan, Harrison M Randall Lab Phys, Ann Arbor, MI 48109 USA. Univ Michigan, Ctr Ultrafast Opt Sci, Ann Arbor, MI 48109 USA. USN, Res Lab, Washington, DC 20375 USA. RP Bonadeo, NH (reprint author), Univ Michigan, Harrison M Randall Lab Phys, Ann Arbor, MI 48109 USA. RI Katzer, D. Scott/N-7841-2013 NR 20 TC 145 Z9 145 U1 1 U2 15 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 28 PY 1998 VL 81 IS 13 BP 2759 EP 2762 DI 10.1103/PhysRevLett.81.2759 PG 4 WC Physics, Multidisciplinary SC Physics GA 123PJ UT WOS:000076133300035 ER PT J AU Ferek, RJ Hegg, DA Hobbs, PV Durkee, P Nielsen, K AF Ferek, RJ Hegg, DA Hobbs, PV Durkee, P Nielsen, K TI Measurements of ship-induced tracks in clouds off the Washington coast SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article AB In situ cloud microphysical measurements are presented for two ship tracks detected off the Washington coast in three successive satellite images from the advanced very high resolution radiometer (AVHRR) channel 3 (3.7 mu m). Aerosol and cloud water chemical data suggest that the tracks were produced by effluents from ship stacks. Cloud droplet spectra measured in the ship tracks had effective radii about one half of those measured in the ambient clouds. A drizzle mode was present in the ambient cloud, but this was largely suppressed in the ship tracks. Analysis of cloud condensation nucleus (CCN) and total particle spectra in and around the ship tracks suggest that the stability of the tracks could have been due to a feedback between the lowering of CCN concentrations as the ship plumes diluted, consequent increases in peak supersaturations in the cloud, and a modest amount of particle growth by gas-to-particle conversion. C1 Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Ferek, RJ (reprint author), Univ Washington, Dept Atmospher Sci, Box 351640, Seattle, WA 98195 USA. EM ferekr@onr.navy.mil; deanhegg@atmos.washington.edu; phobbs@atmos.washington.edu; durkee@nps.navy.mil; kurt@moe.met.nps.navy.mil NR 13 TC 45 Z9 52 U1 1 U2 6 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 SEP 27 PY 1998 VL 103 IS D18 BP 23199 EP 23206 DI 10.1029/98JD02121 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 126PT UT WOS:000076302900012 ER PT J AU Montgomery, HE AF Montgomery, HE TI Two-electron wavefunctions. Fourteenth-order expectation values SO CHEMICAL PHYSICS LETTERS LA English DT Article AB Variational perturbation theory is used to calculate a 14-order ground-state wavefunction for two electrons moving about a nucleus of charge Z. Fractional exponents are used to approximate the logarithmic terms in the exact wavefunction. Perturbation expansion coefficients for 15 operators are then calculated. Estimates of the accuracy of the calculation are obtained by comparison with exactly known first-order expectation values and with expectation values recovered from the perturbation energies of Baker, Freund, Hill and Morgan (Phys. Rev. A 41 (1990) 1247). (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. RP Montgomery, HE (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02841 USA. NR 13 TC 7 Z9 7 U1 0 U2 0 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 SEP 25 PY 1998 VL 294 IS 6 BP 468 EP 472 DI 10.1016/S0009-2614(98)00928-2 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 124RP UT WOS:000076195900004 ER PT J AU Coxon, AB Ward, JM Geradts, J Otterson, GA Zajac-Kaye, M Kaye, FJ AF Coxon, AB Ward, JM Geradts, J Otterson, GA Zajac-Kaye, M Kaye, FJ TI RET cooperates with RB/p53 inactivation in a somatic multi-step model for murine thyroid cancer SO ONCOGENE LA English DT Article DE mouse model; p53; RB; Ret; thyroid cancer ID GERMLINE MUTATIONS; MICE; RB; TUMORS; SYSTEM; P53 AB Mice bred to carry germline Rb and p53 null alleles are associated with a tumor spectrum that overlaps with the inherited multiple endocrine neoplasia-1 (MEN1) and MEN2 syndromes in humans, including medullary thyroid cancer (MTC). To study the genetic basis for these tumors, we microdissected MTC specimens or obtained fresh MTC tissue from nine independent Rb+/- p53(+/-) mice, amplified the region of the Ret gene known to be mutated in human MTC, and detected acquired missense Ret mutations in four different mice, These mutations were Localized to a group of tandem cysteines which are analogous to activating germline mutations observed in human MEN2A and familial MTC (FMTC), To determine whether the remaining wild type Rb allele was inactivated in these murine MTC samples, we subjected tumor tissue to immunohistochemical staining with an Rb antibody, and demonstrated the absence of RE staining in murine MTC, while normal tissue retained RE nuclear staining. These findings demonstrate the ability of the gene knockout model to recapitulate somatic multi-step tumorigenesis and suggest that the development of a murine neuroendocrine tumor requires mutational dysregulation within both receptor tyrosine kinase and nuclear tumor suppressor gene pathways. C1 NCI, Dept Genet, Bethesda, MD 20889 USA. Natl Naval Med Ctr, Bethesda, MD 20889 USA. Div Basic Sci, Anim Sci Branch, Vet & Tumor Pathol Sect, Frederick, MD 21702 USA. Univ N Carolina, Dept Lab Med & Pathol, Chapel Hill, NC 27599 USA. RP Kaye, FJ (reprint author), Naval Hosp, NCI, Bldg 8-Rm 5101, Bethesda, MD 20889 USA. RI kaye, frederic/E-2437-2011 NR 12 TC 32 Z9 32 U1 0 U2 1 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 0950-9232 J9 ONCOGENE JI Oncogene PD SEP 24 PY 1998 VL 17 IS 12 BP 1625 EP 1628 DI 10.1038/sj.onc.1202381 PG 4 WC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity GA 122UM UT WOS:000076089900015 PM 9794240 ER PT J AU Nielsen, AT Chafin, AP Christian, SL Moore, DW Nadler, MP Nissan, RA Vanderah, DJ Gilardi, RD George, CF Flippen-Anderson, JL AF Nielsen, AT Chafin, AP Christian, SL Moore, DW Nadler, MP Nissan, RA Vanderah, DJ Gilardi, RD George, CF Flippen-Anderson, JL TI Synthesis of polyazapolycyclic caged polynitramines SO TETRAHEDRON LA English DT Article ID ENERGETIC MATERIALS; TERTIARY-AMINES; THERMAL-DECOMPOSITION; HEXANITROHEXAAZAISOWURTZITANE; NITRAMINES; NITROSAMINES; GLYOXAL; HEXANITROHEXAZAISOWURTZITANE; DISSOCIATION; CONDENSATION AB Syntheses of new polyazapolycyclic caged polynitramines are described. Sequentially reacting 4, 10-dibenzyl-2,6,8, 12-tetraacetyl-2,4,6,8, 10,12-hexaazaisowurtzitane (5a) with NOBF4 and NO2BF4 in sulfolane solvent produces 2,4,6,8,10,12-hexanitro-2,4,6,8, 10, 12-hexaazaisowurtzitane (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo-[5.5.0.0(5,9).0(3,11)]dodecane, 6). Syntheses of two new polyazapolycyclic caged trinitramines, 3,5,12-trinitro-3,5,12-triazawurtzitane (7a) and 2,4,10-trinitro-2,4, 10-triazaadamantane (12a), as well as their labile parent secondary amines, are discussed. A new caged polynitrosamine, 3,5,12-trinitroso-3,5,12-triazawurtzitane (7d), has been obtained by ring-cleavage nitrosation of the new hexamine-wurtzitane compound 3,5,7,9-tetraazahexacyclo-[9.3.1.1(3,7).0(2,9).0(4,13).0(5,10)]-hexadecane (10). (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Air Warfare Ctr, Weap Ctr, Chem & Mat Branch,Res & Technol Grp, China Lake, CA 93555 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Nielsen, AT (reprint author), USN, Air Warfare Ctr, Weap Ctr, Chem & Mat Branch,Res & Technol Grp, China Lake, CA 93555 USA. NR 86 TC 234 Z9 259 U1 2 U2 40 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4020 J9 TETRAHEDRON JI Tetrahedron PD SEP 24 PY 1998 VL 54 IS 39 BP 11793 EP 11812 PG 20 WC Chemistry, Organic SC Chemistry GA 117GA UT WOS:000075771500008 ER PT J AU Seidl, PA Celata, CM Chupp, WW Faltens, A Fawley, WM Ghiorso, W Hahn, K Henestroza, E MacLaren, S Peters, C Grote, DP Haber, I AF Seidl, PA Celata, CM Chupp, WW Faltens, A Fawley, WM Ghiorso, W Hahn, K Henestroza, E MacLaren, S Peters, C Grote, DP Haber, I TI Progress on the scaled beam-combining experiment at LBNL SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Combined Symposium on Heavy Ion Inertial Fusion / Workshop in Atomic Physics for Ion Beam Fusion CY SEP 22-27, 1997 CL HEIDELBERG UNIV, HEIDELBERG, GERMANY SP GSI, Karlsruhe Res Ctr FZK, Fusion Programme European Commiss, Heraeus Fdn HO HEIDELBERG UNIV DE heavy-ion inertial fusion; ion beam dynamics AB Transverse beam combining is a cost-saving option employed in many designs for induction linac heavy-ion fusion drivers. The resultant transverse emittance increase, due partly to anharmonic space charge forces, must be kept minimal so that the beam remains focusable at the target. A prototype combining experiment has been built. Four sources each produce 4.5 mA Cs+ beams at 160 keV. Focusing upstream of the merge consists of four quadrupoles and a final combined-function element (quadrupole and dipole). Due to the small distance between beams near the merge (similar to 3-4 mm), the electrodes of the final element for each beam are a cage of small rods, each at a different voltage. Recent results are presented along with plans for modifications and future measurements. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. USN, Res Lab, Washington, DC 20375 USA. RP Seidl, PA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS 47-112, Berkeley, CA 94720 USA. NR 7 TC 11 Z9 11 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 SEP 21 PY 1998 VL 415 IS 1-2 BP 243 EP 248 DI 10.1016/S0168-9002(98)00390-8 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 131BQ UT WOS:000076556200038 ER PT J AU Haber, I Callahan, DA Friedman, A Grote, DP Lund, SM Wang, TF AF Haber, I Callahan, DA Friedman, A Grote, DP Lund, SM Wang, TF TI Characteristics of an electrostatic instability driven by transverse-longitudinal temperature anisotropy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Combined Symposium on Heavy Ion Inertial Fusion / Workshop in Atomic Physics for Ion Beam Fusion CY SEP 22-27, 1997 CL HEIDELBERG UNIV, HEIDELBERG, GERMANY SP GSI, Karlsruhe Res Ctr FZK, Fusion Programme European Commiss, Heraeus Fdn HO HEIDELBERG UNIV DE beam instability; particle-in-cell; beam transport; space charge; simulation AB Simulations have previously been reported which exhibit an electrostatic instability that couples thermal energy towards isotropy in a beam with transverse temperature sufficiently greater than the longitudinal temperature. The nature of this instability is observed to be insensitive to details of the initial beam distribution as well as the focusing geometry. Simulations of a uniformly-focused axisymmetric beam with an initial K-V distribution are compared to predictions of an analytic formalism which describes the instability in terms of an infinite series of transverse Gluckstern modes which become coupled to satisfy the full system of longitudinal/transverse equations. A finite truncation of the series is then used to numerically evaluate the instability characteristics. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Haber, I (reprint author), USN, Res Lab, Div Plasma Phys, Code 4790,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 11 TC 12 Z9 12 U1 2 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 SEP 21 PY 1998 VL 415 IS 1-2 BP 405 EP 410 DI 10.1016/S0168-9002(98)00519-1 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 131BQ UT WOS:000076556200064 ER PT J AU Kishek, RA Bernal, S Reiser, M Venturini, M Wang, JG Haber, I Godlove, TF AF Kishek, RA Bernal, S Reiser, M Venturini, M Wang, JG Haber, I Godlove, TF TI Beam dynamics simulations of the University of Maryland Electron-Ring Project SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Combined Symposium on Heavy Ion Inertial Fusion / Workshop in Atomic Physics for Ion Beam Fusion CY SEP 22-27, 1997 CL HEIDELBERG UNIV, HEIDELBERG, GERMANY SP GSI, Karlsruhe Res Ctr FZK, Fusion Programme European Commiss, Heraeus Fdn HO HEIDELBERG UNIV DE beam transport; circular accelerators; injection; particle-in-cell; simulations; space-charge-dominated beams AB A 3-D particle-in-cell code, WARP, is being used to study the self-consistent nonlinear dynamics of the space-charge-dominated beam in the University of Maryland E-ring project. Early work was concentrated on general studies of beam propagation in the nominal ring lattice, as well as more detailed calculations in the injector transport line. Simulations of the ring lattice are being used to address fundamental questions such as emittance growth, which can be caused by nonlinearities in the focusing elements, as well as distortions in the beam equilibrium by the bends. A preliminary design of the injector matching section is presented. Simulations of the injector section emphasize the relationship between the predictions of numerical models and the experimental measurements, in order to understand the requirements for adequately modeling the specific focusing elements used. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Maryland, Energy Res Facil, Inst Plasma Res, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. FM Technol Inc, Fairfax, VA USA. RP Kishek, RA (reprint author), Univ Maryland, Energy Res Facil, Inst Plasma Res, 223, College Pk, MD 20742 USA. RI Bernal, Santiago/B-8167-2017 OI Bernal, Santiago/0000-0001-8287-6601 NR 4 TC 3 Z9 3 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 SEP 21 PY 1998 VL 415 IS 1-2 BP 417 EP 421 DI 10.1016/S0168-9002(98)00607-X PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 131BQ UT WOS:000076556200066 ER PT J AU Wang, JG Bernal, S Chin, P Godlove, TF Haber, I Kishek, R Li, Y Reiser, M Venturini, M York, RC Zou, Y AF Wang, JG Bernal, S Chin, P Godlove, TF Haber, I Kishek, R Li, Y Reiser, M Venturini, M York, RC Zou, Y TI Studies of the physics of space-charge-dominated beams for heavy ion inertial fusion SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Combined Symposium on Heavy Ion Inertial Fusion / Workshop in Atomic Physics for Ion Beam Fusion CY SEP 22-27, 1997 CL HEIDELBERG UNIV, HEIDELBERG, GERMANY SP GSI, Karlsruhe Res Ctr FZK, Fusion Programme European Commiss, Heraeus Fdn HO HEIDELBERG UNIV DE space charge; longitudinal instability; collective effects; beam transport; beam dynamics; circular accelerators ID LOCALIZED PERTURBATIONS; EMITTANCE GROWTH; PARTICLE BEAMS; ELECTRON-BEAM; WAVES; BUNCH AB At the University of Maryland our research on beam physics focuses on space-charge effects and collective phenomena in high-intensity, high-brightness beams for advanced accelerator applications such as drivers for heavy ion inertial fusion. In this paper, we present results of recent beam physics experiments including study of the resistive-wall instability and beam transport in a FODO lattice. Sire also report on the status of an electron ring project to study the recirculation of beam currents well beyond the normal tune-shift limit. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. FM Technol Inc, Fairfax, VA 22032 USA. USN, Res Lab, Washington, DC 20375 USA. Michigan State Univ, Nscl, E Lansing, MI 48824 USA. RP Wang, JG (reprint author), Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. RI Bernal, Santiago/B-8167-2017 OI Bernal, Santiago/0000-0001-8287-6601 NR 21 TC 1 Z9 1 U1 1 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 SEP 21 PY 1998 VL 415 IS 1-2 BP 422 EP 427 DI 10.1016/S0168-9002(98)00414-8 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 131BQ UT WOS:000076556200067 ER PT J AU Grote, DP Friedman, A Haber, I Fawley, W Vay, JL AF Grote, DP Friedman, A Haber, I Fawley, W Vay, JL TI New developments in WARP: Progress toward end-to-end simulation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Combined Symposium on Heavy Ion Inertial Fusion / Workshop in Atomic Physics for Ion Beam Fusion CY SEP 22-27, 1997 CL HEIDELBERG UNIV, HEIDELBERG, GERMANY SP GSI, Karlsruhe Res Ctr FZK, Fusion Programme European Commiss, Heraeus Fdn HO HEIDELBERG UNIV DE IFE driver; particle-in-cell; simulation ID PARTICLE AB The development of a high current, heavy-ion beam driver for inertial confinement fusion requires a detailed understanding of the behavior of the beam, including effects of the strong self-fields. The necessity of including the self-fields of the beam makes particle-in-cell (PIC) simulation techniques ideal, and for this reason, the multi-dimensional PIC/accelerator code WARP has been developed. WARP [1] has been used extensively to study the creation and propagation of ion beams both in experiments and for the understanding of basic beam physics. An overview of the structure of the code will be presented along with a discussion of features that make the code an effective tool in the understanding of space-charge dominated beam behavior. Much development has been done on WARP increasing its flexibility and generality. Major additions include a generalized field description, an efficient steady-state modeling technique, a transverse slice model with a bending algorithm, further improvement of the parallel processing version, and capabilities for Linking to chamber transport codes. With these additions, the capability of modeling a large scale accelerator from end-to-end comes closer to reality. Published by Elsevier Science B.V. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. USN, Res Lab, Washington, DC 20375 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Grote, DP (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 12 TC 51 Z9 51 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 SEP 21 PY 1998 VL 415 IS 1-2 BP 428 EP 432 DI 10.1016/S0168-9002(98)00608-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 131BQ UT WOS:000076556200068 ER PT J AU Friedman, A Barnard, JJ Grote, DP Haber, I AF Friedman, A Barnard, JJ Grote, DP Haber, I TI Simulation studies of transverse resonance effects in space-charge-dominated beams SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT Combined Symposium on Heavy Ion Inertial Fusion / Workshop in Atomic Physics for Ion Beam Fusion CY SEP 22-27, 1997 CL HEIDELBERG UNIV, HEIDELBERG, GERMANY SP GSI, Karlsruhe Res Ctr FZK, Fusion Programme European Commiss, Heraeus Fdn HO HEIDELBERG UNIV DE resonance; mismatch; recirculator; storage ring; simulation; particle-in-cell AB Particle-in-cell simulations exploring the effects of transverse envelope resonances on the emittance of space-charge-dominated beams have been carried out using a new 2-D transverse "slice" model in the WARP particle-in-cell code. In this paper, we consider resonances between an applied quadrupole field error and harmonics of the asymmetric mismatch mode of beam envelope oscillation. We examine both acceleration and bunching, and show that rapid passage through a major resonance significantly reduces the attendant emittance growth. Published by Elsevier Science B.V. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. USN, Res Lab, Washington, DC 20375 USA. RP Friedman, A (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,Mail Stop L-645, Livermore, CA 94551 USA. NR 7 TC 13 Z9 12 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 SEP 21 PY 1998 VL 415 IS 1-2 BP 455 EP 459 DI 10.1016/S0168-9002(98)00419-7 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 131BQ UT WOS:000076556200073 ER PT J AU Mintmire, JW White, CT AF Mintmire, JW White, CT TI Universal density of states for carbon nanotubes SO PHYSICAL REVIEW LETTERS LA English DT Article ID NANOSCALE GRAPHITIC TUBULES; ELECTRONIC-STRUCTURE; GRAPHENE TUBULES AB =The density of states in the vicinity of the Fermi level of single-wall carbon nanotubes can be expressed in terms of a universal relationship that depends only on whether the nanotube is metallic or semiconducting. We compare the predictions of this approximate relationship with densities of states calculated using first-principles band structure results. These comparisons show that: this approximation works well for energies within about 1 eV of the Fermi level. [S0031-9007(98)07 132-4]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Mintmire, JW (reprint author), USN, Res Lab, Code 6179, Washington, DC 20375 USA. OI Mintmire, John/0000-0002-6551-0349 NR 18 TC 396 Z9 402 U1 5 U2 57 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 21 PY 1998 VL 81 IS 12 BP 2506 EP 2509 DI 10.1103/PhysRevLett.81.2506 PG 4 WC Physics, Multidisciplinary SC Physics GA 122LM UT WOS:000076073100027 ER PT J AU Bayer, M Gutbrod, T Reithmaier, JP Forchel, A Reinecke, TL Knipp, PA Dremin, AA Kulakovskii, VD AF Bayer, M Gutbrod, T Reithmaier, JP Forchel, A Reinecke, TL Knipp, PA Dremin, AA Kulakovskii, VD TI Optical modes in photonic molecules SO PHYSICAL REVIEW LETTERS LA English DT Article ID NEAR-INFRARED WAVELENGTHS; SPONTANEOUS EMISSION; BAND-STRUCTURE; QUANTUM DOTS; MICROCAVITY; STATES; GAP AB Photonic molecules have been fabricated by coupling pairs of micrometer-sized semiconductor cavities via a narrow channel. The optical modes in these structures have been studied spectroscopically as a function of the coupling and the mode energies are compared to detailed calculations. These results provide a rich picture of photonic modes in these molecules. [S0031-9007(98)07060-4]. C1 Univ Wurzburg, D-97074 Wurzburg, Germany. USN, Res Lab, Washington, DC 20375 USA. Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Russia. RP Bayer, M (reprint author), Univ Wurzburg, D-97074 Wurzburg, Germany. RI Reithmaier, Johann/G-8171-2012; OI Reithmaier, Johann/0000-0002-1974-8292; Forchel, Alfred/0000-0002-9377-9935 NR 24 TC 234 Z9 239 U1 2 U2 35 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 21 PY 1998 VL 81 IS 12 BP 2582 EP 2585 DI 10.1103/PhysRevLett.81.2582 PG 4 WC Physics, Multidisciplinary SC Physics GA 122LM UT WOS:000076073100046 ER PT J AU Harra-Murnion, LK Schmieder, B van Driel-Gesztelyi, L Sato, J Plunkett, SP Rudawy, P Rompolt, B Akioka, M Sakao, T Ichimoto, K AF Harra-Murnion, LK Schmieder, B van Driel-Gesztelyi, L Sato, J Plunkett, SP Rudawy, P Rompolt, B Akioka, M Sakao, T Ichimoto, K TI Multi-wavelength observations of post flare loops in two long duration solar flares SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : flares; Sun : X-rays, gamma rays ID X-RAY TELESCOPE; 26 JUNE 1992; MAGNETIC RECONNECTION; PHYSICAL PARAMETERS; POSTFLARE LOOPS; A MISSION; HOT; YOHKOH; COOL; EVOLUTION AB We have analysed two Long Duration solar Events (LDEs) which produced large systems of Post Flare Loops (PFLs) and which have been observed by Yohkoh and groundbased observatories. Using the Maximum Entropy Method (MEM) image synthesis technique with new modulation patterns we were able to make hard X-ray (HXR) images of the post flare loops recorded in the L Channel (13.9-22.7 keV) of the Yohkoh Hard X-ray Telescope. We obtained co-aligned 2-D maps in H alpha (10(4) K), in soft X-rays (5 x 10(6) K) and in hard Xrays (20 x 10(6) K). We conclude that the soft X-ray (SXR) loops lie higher than the H alpha loops and the former are overlaid by HXR emission. This is suggestive of the magnetic reconnection process. However some details are not consistent with the standard models. Firstly the separation between the HXR source and the SXR loop increases with time, with the HXR source being approximately a factor of five larger than the equivalent source in impulsive flares. Secondly the cooling times deduced from observations are longer than the theoretically expected ones and the discrepancy increases with time. We review the current models in view of these results. C1 UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Observ Paris, DASOP, F-92195 Meudon, France. Univ Oslo, N-0315 Oslo, Norway. Konkoly Observ Budapest, H-1525 Budapest, Hungary. Natl Astron Observ, Tokyo 181, Japan. USN, Res Lab, Univ Space Res Assoc, Washington, DC 20375 USA. Univ Wroclaw, Astron Inst, PL-51622 Wroclaw, Poland. Hiraiso Solar Terr Res Ctr, Commun Res Lab, Nakaminato, Ibaraki 31112, Japan. RP Harra-Murnion, LK (reprint author), UCL, Mullard Space Sci Lab, Holmbury St Mary, Dorking RH5 6NT, Surrey, England. OI Harra, Louise/0000-0001-9457-6200 NR 39 TC 42 Z9 43 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 SEP 20 PY 1998 VL 337 IS 3 BP 911 EP 920 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 123KJ UT WOS:000076124100031 ER PT J AU Wood, BE Karovska, M Cook, JW Brueckner, GE Howard, RA Korendyke, CM Socker, DG AF Wood, BE Karovska, M Cook, JW Brueckner, GE Howard, RA Korendyke, CM Socker, DG TI Search for brightness variations in Fe xiv Coronagraph observations of the quiescent solar corona SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona ID X-RAY TELESCOPE; TRANSIENT BRIGHTENINGS; LOOP INTERACTION; HIGH-RESOLUTION; ACTIVE REGIONS; FLARES; YOHKOH; RECONNECTION; OSCILLATIONS; MORPHOLOGY AB We use Fe XIV 5303 Angstrom green line images obtained by the Large Angle Spectrometric Coronagraph (LASCO) on board SOHO to search for variability in the quiescent solar corona in the shortest observable timescales. The observing program obtained Fe XIV images of a small area of the inner corona every 2 minutes over a period of 1 hr. We present results from two executions of this program taken several months apart. The most obvious variability observed in the two sequences is in the form of quasi-steady brightening on timescales of at least an hour. Of particular interest are two compact loops that are observed to vary significantly during the course of the observations. Superposed on the long-term brightening in these loops are statistically significant variations on timescales of about 30 minutes. In both loops, the overall brightening is greatest at the apparent loop tops, where the intensity increases by at least 25%. In one loop there appears to be a flow up one of the legs of the loop. We place these observations in context with earlier observations of coronal variability, and we discuss the energy requirements for the observed brightening. Emission measures computed from Fe XIV intensities measured within the two brightening loops are over an order of magnitude lower than those typically found for active regions on the solar disk, which suggests significantly lower average densities. For one of the loops, we measure densities in the range n(e) = (5.0-7.4) x 10(8) cm(-3). Lower than average densities are expected for the two loops, given that they reach more than 1 pressure scale height above the solar limb. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 46 TC 8 Z9 8 U1 0 U2 0 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 SEP 20 PY 1998 VL 505 IS 1 BP 432 EP 442 DI 10.1086/306159 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LA UT WOS:000077777900037 ER PT J AU Campbell, ML AF Campbell, ML TI Kinetic study of gas-phase Y(a(2)D(3/2)) and La(a(2)D(3/2)) with O-2, N2O, CO2 and NO SO CHEMICAL PHYSICS LETTERS LA English DT Article ID TRANSITION-METAL ATOMS; GROUP IIIB ATOMS; CHEMILUMINESCENT REACTIONS; MOLECULAR-BEAM; OXIDATION; O2; FLUORESCENCE; DEPLETION; ALKANES; ALKENES AB The second-order rate constants of gas-phase Y(a(2)D(3/2)) and La(a(2)D(3/2)) with O-2, N2O, CO2 and NO as a function of temperature are reported. In all cases, the reactions are relatively fast. For Y(a(2)D(3/2)), the bimolecular rate constants (in cm(3) s(-1)) are described in Arrhenius form by k(O-2) = (2.2 +/- 0.1) X 10(-10) exp(-3.5 +/- 0.6 kJ mol(-1)/RT), k(N2O) = (1.9 +/- 0.2) X 10(-10) exp( -4.0 +/- 0.8 kJ mol(-1)/RT), k(CO2) = (1.0 +/- 0.1) x 10(-10) exp(-2.3 +/- 0.6 kJ mol(-1)/RT), where the uncertainties are +/-2 sigma. The rate constants for Y reacting with NO are temperature insensitive with a value of 1.0 X 10(-10) cm(3) s(-1). For La(a(2)D(3/2)), the bimolecular rate constants for all the reactants are near the gas-kinetic collision rate. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP Campbell, ML (reprint author), USN Acad, Dept Chem, Annapolis, MD 21402 USA. NR 29 TC 22 Z9 22 U1 0 U2 2 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 SEP 18 PY 1998 VL 294 IS 4-5 BP 339 EP 344 DI 10.1016/S0009-2614(98)00905-1 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 122JQ UT WOS:000076068800012 ER PT J AU Spears, WM AF Spears, WM TI A compression algorithm for probability transition matrices SO SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS LA English DT Article DE probability transition matrix; transient behavior; compression; lumping; aggregation AB This paper describes a compression algorithm for probability transition matrices. The compressed matrix is itself a probability transition matrix. In general the compression is not error free, but the error appears to be small even for high levels of compression. C1 USN, Res Lab, AI Ctr, Washington, DC 20375 USA. RP USN, Res Lab, AI Ctr, Code 5514,4555 Overlook Ave, Washington, DC 20375 USA. EM spears@aic.nrl.navy.mil NR 12 TC 13 Z9 15 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0895-4798 EI 1095-7162 J9 SIAM J MATRIX ANAL A JI SIAM J. Matrix Anal. Appl. PD SEP 16 PY 1998 VL 20 IS 1 BP 60 EP 77 DI 10.1137/S0895479897316916 PG 18 WC Mathematics, Applied SC Mathematics GA 121RP UT WOS:000076028000005 ER PT J AU Shinohara, YT Edwards, K Thompson-Bowers, J AF Shinohara, YT Edwards, K Thompson-Bowers, J TI Protocol for initial evaluation of occupational exposure to HIV and initiation of antiretroviral prophylaxis SO AMERICAN JOURNAL OF HEALTH-SYSTEM PHARMACY LA English DT Article C1 USN, Med Ctr, Dept Pharm, San Diego, CA 92134 USA. USN, Med Ctr, Dept Occupat Hlth, San Diego, CA 92134 USA. USN, Med Ctr, Dept Infect Control, San Diego, CA 92134 USA. RP Shinohara, YT (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC HEALTH-SYSTEM PHARMACISTS PI BETHESDA PA 7272 WISCONSIN AVE, BETHESDA, MD 20814 USA SN 1079-2082 J9 AM J HEALTH-SYST PH JI Am. J. Health-Syst. Pharm. PD SEP 15 PY 1998 VL 55 IS 18 BP 1921 EP 1924 PG 4 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 121CR UT WOS:000075995000018 PM 9784773 ER PT J AU Siskind, DE Froidevaux, L Russell, JM Lean, J AF Siskind, DE Froidevaux, L Russell, JM Lean, J TI Implications of upper stratospheric trace constituent changes observed by HALOE for O-3 and ClO from 1992 to 1995 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID OZONE; VARIABILITY; BUDGET; MODEL AB Measurements from the Halogen Occultation Experiment (HALOE) of the upper stratosphere show increases in HCl and H2O and decreases in CH4 and O-3 during the period 1992-1995. These changes all coincide with the decline of solar cycle 22. Using a simple photochemical model, we find that 4 major components contribute to the O-3 decrease: 1) an increase in total chlorine as indicated by increasing HCl 2) an additional increase in reactive chlorine due to repartitioning of Cly by the decreasing CH4 3) a decrease in odd oxygen production due to decreased solar flux and 4) an increase in odd hydrogen loss due to increasing H2O. At 2 mbar, the Cly repartitioning is the largest cause of O-3 changes. Because the Cly repartitioning coincides with decreasing solar flux, some recent observational estimates of the long-term response of upper stratospheric, O-3 to solar UV irradiance variability may be too large. Compared with the HALOE O-3 data, the model O-3 exhibits a larger negative trend. This appears to be because the model O-3 is more sensitive to the increased H2O than is the observed O-3. The 20-30% decline in CH4 also implies a large increase in ClO which exceeds that expected from CFCs. Observations of ClO from the Microwave Limb Sounder (MLS) support this inference. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Siskind, DE (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7641, Washington, DC 20375 USA. OI Lean, Judith/0000-0002-0087-9639 NR 17 TC 24 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 SEP 15 PY 1998 VL 25 IS 18 BP 3513 EP 3516 DI 10.1029/98GL02664 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 119MK UT WOS:000075900100034 ER PT J AU White, WB Cayan, DR Lean, J AF White, WB Cayan, DR Lean, J TI Global upper ocean heat storage response to radiative forcing from changing solar irradiance and increasing greenhouse gas/aerosol concentrations SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID TEMPERATURE AB We constructed gridded fields of diabatic heat storage changes in the upper ocean from 20 degrees S to 60 degrees N from historical temperature profiles collected from 1955 to 1996. We filtered these 42 year records for periods of 8 to 15 years and 15 to 30 years, producing depth-weighted vertical average temperature (DVT) changes from the sea surface to the top of the main pycnocline. Basin and global averages of these DVT changes reveal decadal and interdecadal variability in phase across the Indian, Pacific, Atlantic, and Global Oceans, each significantly correlated with changing surface solar radiative forcing at a lag of 0 +/- 2 years. Decadal and interdecadal changes in global average DVT are 0.06 degrees +/- 0.01 degrees K and 0.04 degrees K +/- 0.01 degrees K, respectively, the same as those expected from consideration of the Stefan-Boltzmann radiation balance (i.e., 0.3 degrees K per W m(-2)) in response to 0.1% changes in surface solar radiative forcing of 0.2 W m(-2) and 0.15 W m(-2), respectively. Global spatial patterns of DVT changes are similar to temperature changes simulated in coupled ocean-atmosphere models, suggesting that natural modes of Earth's variability are phase-locked to the solar irradiance cycle. A trend in global average DVT of 0.15 degrees K over this 42 year record cannot be explained by changing surface solar radiative forcing. But when we consider the 0.5 W m(-2) increase in surface radiative forcing estimated from the increase in atmospheric greenhouse gas and aerosol (GGA) concentrations over this period [Intergovernmental Panel on Climate Change, 1995], the Stefan-Boltzmann radiation balance yields this observed change. Moreover, the sum of solar and GGA surface radiative forcing can explain the relatively sharp increase in global and basin average DVT in the late 1970's. C1 Univ Calif San Diego, Scripps Inst Oceanog, Phys Oceanog Res Div, La Jolla, CA 92093 USA. US Geol Survey, San Diego, CA 92123 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ Calif San Diego, Scripps Inst Oceanog, Div Climate Res, La Jolla, CA 92093 USA. RP White, WB (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Phys Oceanog Res Div, 9500 Gilman Dr, La Jolla, CA 92093 USA. EM wbwhite@ucsd.edu; dcayan@ecsd.edu; lean@demeter.nrl.navy.mil NR 24 TC 42 Z9 46 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD SEP 15 PY 1998 VL 103 IS C10 BP 21355 EP 21366 DI 10.1029/98JC01477 PG 12 WC Oceanography SC Oceanography GA 118WG UT WOS:000075863500002 ER PT J AU Perkins, H Hopkins, TS Malmberg, SA Poulain, PM Warn-Varnas, A AF Perkins, H Hopkins, TS Malmberg, SA Poulain, PM Warn-Varnas, A TI Oceanographic conditions east of Iceland SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID FAEROES FRONT; FAROE FRONT; CIRCULATION; WATER; VARIABILITY; SEAS; VORTICITY; OVERFLOW; DRIFTERS; EDDIES AB Circulation and hydrography on the shelf east of Iceland and on the western portion of the Iceland-Faeroe Ridge is described by a series of surveys using temperature-salinity profilers, moored current meters and satellite-tracked drifters. The dominant surface current of the region is the northeastward flow of North Atlantic Water at the shelf break southeast of Iceland as it leaves the shelf to join the Iceland-Faeroe Front. On the bottom beneath it flowing in the opposite direction is a strong, steady current composed of water from the Nordic Seas that has overflowed the ride and followed along bathymetric contours. North of the front, three comparatively weak currents are identified, formed by splitting of the North Icelandic Irminger Current after it has rounded the northeast corner of Iceland. One branch, the East Icelandic Current, is confined to the shelf and produces a mean, southward flow until it turns eastward to join the Iceland-Faeroe Front. Another leaves the shelf to form the shallow, southeastward flowing Icelandic Current. The third follows deeper contours of the continental slope and renews waters on the northern flank of the Iceland-Faeroe Ridge. C1 SACLANT Res Ctr, La Spezia, Italy. Marine Res Inst, IS-121 Reykjavik, Iceland. RP Perkins, H (reprint author), USN, Res Lab, Code 7332, Stennis Space Ctr, MS 39529 USA. NR 30 TC 22 Z9 22 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD SEP 15 PY 1998 VL 103 IS C10 BP 21531 EP 21542 DI 10.1029/98JC00890 PG 12 WC Oceanography SC Oceanography GA 118WG UT WOS:000075863500012 ER PT J AU Marmorino, GO Shen, CY Allan, N Askari, F Trizna, DB Trump, CL Shay, LK AF Marmorino, GO Shen, CY Allan, N Askari, F Trizna, DB Trump, CL Shay, LK TI An occluded coastal oceanic front SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID TIDAL INTRUSION FRONT; LOW GRAZING ANGLES; CAPE-HATTERAS; CONTINENTAL-SHELF; APERTURE RADAR; SURFACE; WATER; NORTH AB Field observations, including hydrographic, microwave imaging radar, and HF radar measurements, reveal the evolution of a complicated frontal interaction between three water masses on the continental shelf near Cape Hatteras, North Carolina, during a period of incursion of water from the Gulf Stream. The water masses were found to be separated by intersecting frontal lines configured in a manner analogous to an occluded atmospheric front. The densest water lay between inshore and offshore fronts that gradually merged or occluded in the generally downstream direction, leaving a single surface front. The overall frontal structure appeared as a distinct Y-shaped feature in the radar imagery, similar to historical imagery of the study area. The interpretation of the observations is aided by the use of a two-dimensional numerical model. The model is initialized with two fronts idealized from the ocean measurements. The model fronts quickly sharpen and begin to move together, eventually occluding into a single surface front. As a result of the occlusion, the water mass having intermediate density subducts and intrudes under the most buoyant water, carrying with it strong horizontal and vertical shears, and a frontal band of diverging currents is created in the densest water mass. The model thus suggests that in the ocean there will be an increase in hydrographic and velocity fine structure downstream of the frontal occlusion point. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Sachs Freeman & Associates Inc, Largo, MD 20774 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA. RP Marmorino, GO (reprint author), USN, Res Lab, Remote Sensing Div, Code 7250, Washington, DC 20375 USA. NR 27 TC 11 Z9 11 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD SEP 15 PY 1998 VL 103 IS C10 BP 21587 EP 21600 DI 10.1029/98JC02099 PG 14 WC Oceanography SC Oceanography GA 118WG UT WOS:000075863500015 ER PT J AU Chu, PC Fan, CW Lozano, CJ Kerling, JL AF Chu, PC Fan, CW Lozano, CJ Kerling, JL TI An airborne expendable bathythermograph survey of the South China Sea, May 1995 SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID NORTH-ATLANTIC CIRCULATION; HYDROGRAPHIC DATA; GENERAL-CIRCULATION; ABSOLUTE VELOCITY; OCEAN AB An extensive airborne expendable bathythermograph survey of the South China Sea (SCS) conducted in May 1995 and historical data are used to analyze and infer the upper layer (300 m) synoptic structure and general circulation. The primary thermal feature observed was a central SCS warm pool surrounded by several cool pools. The size of the warm pool decrease with depth from approximately 200,000 km(2) at 50 m depth to about 70,000 km(2) at 300 m depth. The maximum temperature of the warm pool was 30 degrees C, appearing near the surface. At the depth of 50 m, the temperature of the central SCS warm pool was 29 degrees C, and the temperature of the five surrounding cool pools ranged from 26 degrees C to 22 degrees C. A three-dimensional estimate of the absolute velocity field was obtained from the observed temperature field and a climatological salinity field using the beta spiral method. Striking circulation features were the existence of dual anticyclonic eddies in the central SCS warm pool and the existence of cyclonic eddies associated with the cool pools. In the upper layer the tangential velocity of the dual central SCS anticyclonic warm-core eddies is around 30-40 cm/s and that of the five cyclonic cool-core eddies varies from 10 cm/s to 40 cm/s. The tangential velocity of all the eddies decreased with depth. At 300 m depth, it became less than 5 cm/s for all the eddies. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. USN, Oceanog Off, Stennis Space Ctr, MS 39529 USA. RP Chu, PC (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 30 TC 64 Z9 88 U1 1 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD SEP 15 PY 1998 VL 103 IS C10 BP 21637 EP 21652 DI 10.1029/98JC02096 PG 16 WC Oceanography SC Oceanography GA 118WG UT WOS:000075863500019 ER PT J AU Viudez, A Pinot, JM Haney, RL AF Viudez, A Pinot, JM Haney, RL TI On the upper layer circulation in the Alboran Sea SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID ALMERIA-ORAN FRONT; SYNOPTIC HYDROGRAPHIC OBSERVATIONS; MEDITERRANEAN WATER; ANTICYCLONIC GYRES; ATLANTIC JET; STRAIT; GIBRALTAR; VARIABILITY; EXPLANATION; CURRENTS AB We present new experimental results and assemble them with previous results in order to develop an improved picture of the upper layer circulation in the Alboran Sea. It is suggested that the key idea to understanding this upper layer circulation is the tendency of the Atlantic jet (AJ) to have negative curvature. Local interactions with the western Alboran gyre (WAG) or the African coast can, however, counterbalance this tendency and modify the anticyclonic path of the AJ. It is also proposed that the density gradients in the WAG can be maintained in part by means of an intermittent surface cross-gyre current which results in an input, mixing, and renewal of Atlantic water. The static stability at the bottom of the gyre increases because of the mixing of Atlantic water with Western Mediterranean Deep Water which is uplifted close to the African coast. This mixing process thereby acts as a local source of potential vorticity. We also report the existence in the Alboran Sea of subsurface anticyclonic eddies (located between 100 and 400 m) of relatively cold water that appear to be detached from the Iberian shelf. Regarding the large-scale variability of the AJ-WAG system, we present evidence of an eastward migration of the WAG and the subsequent formation of a new anticyclonic gyre in the western Alboran basin on a timescale of 1 month. This eastward gyre migration process temporarily allows the simultaneous presence of three anticyclonic gyres in the Alboran Sea. C1 USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. Univ Illes Balears, Dept Fis, E-07071 Palma de Mallorca, Spain. RP Viudez, A (reprint author), Univ Illes Balears, Dept Fis, E-07071 Palma de Mallorca, Spain. EM dfsavL4@ps.uib.es; dfsjmp4@ps.uib.ec; heneyrl@met.nps.navy.mil RI Viudez, Alvaro/A-8201-2008 OI Viudez, Alvaro/0000-0001-7862-9835 NR 51 TC 55 Z9 55 U1 2 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD SEP 15 PY 1998 VL 103 IS C10 BP 21653 EP 21666 DI 10.1029/98JC01082 PG 14 WC Oceanography SC Oceanography GA 118WG UT WOS:000075863500020 ER PT J AU Hwang, SG Krauter, AR Michael, TS AF Hwang, SG Krauter, AR Michael, TS TI An upper bound for the permanent of a nonnegative matrix SO LINEAR ALGEBRA AND ITS APPLICATIONS LA English DT Article AB Let A be a fully indecomposable, nonnegative matrix of order n with row sums r(1),..., r(n), and let s(i) equal the smallest positive element in row i of A. We prove the permanental inequality per(A) less than or equal to (i=1)Pi(n)S(i) + (i=1)Pi(n)(r(i)-s(i)) and characterize the case of equality. In 1984 Donald, Elwin, Hager, and Salamon gave a graph-theoretic proof of the special case in which A is a nonnegative integer matrix. (C) 1998 Elsevier Science Inc. All rights reserved. C1 USN Acad, Dept Math, Annapolis, MD 21402 USA. Kyungpook Natl Univ, Teachers Coll, Dept Math Educ, Taegu 702701, South Korea. Montanuniv Leoben, Inst Math & Angew Geometrie, A-8700 Leoben, Austria. RP Michael, TS (reprint author), USN Acad, Dept Math, Annapolis, MD 21402 USA. NR 4 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0024-3795 J9 LINEAR ALGEBRA APPL JI Linear Alg. Appl. PD SEP 15 PY 1998 VL 281 IS 1-3 BP 259 EP 263 DI 10.1016/S0024-3795(98)10040-X PG 5 WC Mathematics, Applied; Mathematics SC Mathematics GA 121ET UT WOS:000076000900014 ER PT J AU Todd, MD Vohra, ST AF Todd, MD Vohra, ST TI Measurement and analysis of complex modulated motions in a weakly nonlinear system SO PHYSICA D LA English DT Article DE weakly nonlinear systems; two-timing systems; spherical pendulum; experimental techniques ID FRACTAL BASIN BOUNDARIES; DRIVEN DAMPED PENDULUM; SPHERICAL PENDULUM; CHAOS; BIFURCATIONS; DYNAMICS; NOISE AB The two-timing dynamics of a forced, weakly nonlinear system are considered. Experimental results on a roll-forced spherical pendulum verify the occurrence of slow-time, subharmonically and chaotically modulated oscillations in a frequency band near resonance; the modulatory behavior follows the occurrence of a Hopf bifurcation in the slow-time coordinates. A phase-sensitive detection method for experimentally isolating the slow-time behavior is described. A Lagrangian model for the pendulum is developed, and slow-time equations are presented. A two-thirds power scaling law relating roll angle to the appearance of the modulations is derived from the slow-time equations and tested with experimental results. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Washington, DC 20375 USA. RP Todd, MD (reprint author), USN, Res Lab, Code 5673, Washington, DC 20375 USA. NR 27 TC 3 Z9 3 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD SEP 15 PY 1998 VL 120 IS 3-4 BP 329 EP 345 DI 10.1016/S0167-2789(98)00094-3 PG 17 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA 113JD UT WOS:000075546600005 ER PT J AU Efros, AL Rosen, M AF Efros, AL Rosen, M TI Quantum size level structure of narrow-gap semiconductor nanocrystals: Effect of band coupling SO PHYSICAL REVIEW B LA English DT Article ID OPTICAL-PROPERTIES; HOLE SPECTRUM; DOTS; ABSORPTION; MODEL; CRYSTALLITES; SPECTROSCOPY; ASSIGNMENT AB We study the size dependence of electron and hole quantum size levels in spherical semiconductor nanocrystals. An analytical theory of the quantum size levels within a spherical eight-band Pidgeon and Brown model has been developed, which takes into account both the coupling of conduction and valence bands and the complex structure of the valence band in nanocrystals with an infinite potential barrier. We show that in narrow gap semiconductors band mixing must always be taken into account and that it may be important even in wide gap semiconductors, because the mixing is governed by the square root of the ratio of the quantization energy to the energy gap. The strength of the coupling also depends on the ratio of the contributions of remote bands to the effective masses of the electron and the light hole. As a result level structure is very sensitive, in general, to the energy band parameters. The calculated level structure for narrow gap InSb, moderate gap CdTe, and wide gap CdS nanocrystals are presented. C1 USN, Res Lab, Nanostruct Opt Sect, Washington, DC 20375 USA. RP Efros, AL (reprint author), USN, Res Lab, Nanostruct Opt Sect, Washington, DC 20375 USA. NR 41 TC 156 Z9 156 U1 5 U2 33 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD SEP 15 PY 1998 VL 58 IS 11 BP 7120 EP 7135 DI 10.1103/PhysRevB.58.7120 PG 16 WC Physics, Condensed Matter SC Physics GA 122EK UT WOS:000076058800066 ER PT J AU Fonda, RW Jones, HN Vandermeer, RA AF Fonda, RW Jones, HN Vandermeer, RA TI The shape memory effect in equiatomic TaRu and NbRu alloys SO SCRIPTA MATERIALIA LA English DT Article C1 USN, Div Mat Sci & Technol, Res Lab, Washington, DC 20375 USA. RP Fonda, RW (reprint author), USN, Div Mat Sci & Technol, Res Lab, Washington, DC 20375 USA. NR 17 TC 60 Z9 64 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD SEP 15 PY 1998 VL 39 IS 8 BP 1031 EP 1037 DI 10.1016/S1359-6462(98)00303-0 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 121QR UT WOS:000076025300005 ER PT J AU Erwin, SC Weitering, HH AF Erwin, SC Weitering, HH TI Theory of the "honeycomb chain-channel" reconstruction of M/Si(111)-(3x1) SO PHYSICAL REVIEW LETTERS LA English DT Article ID STRUCTURAL MODEL; SURFACES; PHOTOEMISSION AB First-principles electronic-structure methods are used to study a structural model for Ag/Si(111)-(3 x 1), recently proposed on the basis of transmission electron diffraction data. The fully relaxed geometry for this model is far more energetically favorable than any previously proposed, partly due to the unusual formation of a Si double bond in the surface layer. The calculated electronic properties of this model are in complete agreement with data from angle-resolved photoemission and scanning tunneling microscopy. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Erwin, SC (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RI Erwin, Steven/B-1850-2009 NR 15 TC 156 Z9 157 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 14 PY 1998 VL 81 IS 11 BP 2296 EP 2299 DI 10.1103/PhysRevLett.81.2296 PG 4 WC Physics, Multidisciplinary SC Physics GA 119LH UT WOS:000075897300029 ER PT J AU Rajagopal, AK AF Rajagopal, AK TI The principle of detailed balance and the Lindblad dissipative quantum dynamics SO PHYSICS LETTERS A LA English DT Article ID DENSITY-MATRIX; SEMIGROUPS; EVOLUTION AB It is shown that by incorporating the principle of detailed balance in the Lindblad dissipative quantum dynamics of the density matrix, the approach to thermal equilibrium not assured in the original formulation of this theory, can be realized. Three examples of current interest illustrate the general formalism. From the last example, we deduce for a low-power InAs HEMT device of about a tenth of a micron size, having the following estimates provided by Dr. W. Kruppa of our Laboratory, R similar to 5 Omega, L similar to 0.1 nH, and C similar to 0.1 pF, the decoherence time similar to 80 ps. Typical tunneling times in a resonant tunneling quantum device is about 0.1 ps, well below the decoherence time estimated above. With this crude estimate, we may conclude that picosecond regimes are classical, while below that, we have quantum regimes. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rajagopal, AK (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 13 TC 22 Z9 22 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD SEP 14 PY 1998 VL 246 IS 3-4 BP 237 EP 241 DI 10.1016/S0375-9601(98)00463-0 PG 5 WC Physics, Multidisciplinary SC Physics GA 119DD UT WOS:000075879500005 ER PT J AU Kostoff, RN AF Kostoff, RN TI The under-reporting of research impact SO SCIENTIST LA English DT Editorial Material AB Under-reporting research impact: The technology exists to track and account for many research benefits, and this activity should be started now, maintains Ronald N. Kostoff. C1 USN, Res Off, Arlington, VA 22217 USA. RP USN, Res Off, Arlington, VA 22217 USA. NR 4 TC 1 Z9 1 U1 0 U2 1 PU LABX MEDIA GROUP PI MIDLAND PA PO BOX 216, 478 BAY ST, MIDLAND, ONTARIO L4R 1K9, CANADA SN 0890-3670 EI 1547-0806 J9 SCIENTIST JI Scientist PD SEP 14 PY 1998 VL 12 IS 18 BP 9 EP 9 PG 1 WC Information Science & Library Science; Multidisciplinary Sciences SC Information Science & Library Science; Science & Technology - Other Topics GA 118KQ UT WOS:000075837600012 ER PT J AU Smith, K Menon, P Rolfe, A Welch, M Barrett, T Crittenden, MJ Skelton, H AF Smith, K Menon, P Rolfe, A Welch, M Barrett, T Crittenden, MJ Skelton, H TI Pretreatment with intralesional hyaluronidase prior to excision of dermatofibrosarcoma protuberans SO CANCER LETTERS LA English DT Article; Proceedings Paper CT Symposium on Novel Aspects in Chemoresistance CY MAR 20, 1998 CL VIENNA, AUSTRIA SP Lainz Hosp, 5th Dept Internal Med Oncol DE pretreatment; intralesional hyaluronidase; dermatofibrosarcoma protuberans ID MOHS MICROGRAPHIC SURGERY; EXTRACELLULAR-MATRIX; SURGICAL MARGINS; CD34 EXPRESSION; IMMUNOREACTIVITY; CANCER; TUMORS; CELLS; CHROMOSOME-17; CARCINOMAS AB Dermatofibrosarcoma protuberans (DFSPs) are an uncommon malignancy that commonly recur, but rarely metastasize. The origin of DFSPs is controversial; however, they stain with the progenitor marker CD34. DFSPs usually show increased stromal mucin, mainly hyaluronic acid (HA). HA increases cellular proliferation, delays differentiation and increases cellular motion. We evaluated the pretreatment of DFSPs with intralesional injections of hyaluronidase (HD) prior to the surgical excision. Five of nine cases of DFSPs were pretreated, with HD. In HD-pretreated cases the margins for excision of the residual tumor were reduced. HD pretreatment also decreased CD34 staining and increased polarizable collagen in the residual tumor. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 Natl Naval Med Ctr, Dept Dermatol, Bethesda, MD 20889 USA. Walter Reed Army Med Ctr, Washington, DC 20307 USA. USN, Med Ctr, San Diego, CA USA. Lab Corp Amer, Herndon, VA USA. RP Smith, K (reprint author), Natl Naval Med Ctr, Dept Dermatol, Bethesda, MD 20889 USA. NR 39 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0304-3835 J9 CANCER LETT JI Cancer Lett. PD SEP 11 PY 1998 VL 131 IS 1 BP 117 EP 126 DI 10.1016/S0304-3835(98)00208-0 PG 10 WC Oncology SC Oncology GA 137XM UT WOS:000076942400015 PM 9839627 ER PT J AU Lavie, Y Zhang, ZC Cao, HT Han, TY Jones, RC Liu, YY Jarman, M Hardcastle, IR Giuliano, AE Cabot, MC AF Lavie, Y Zhang, ZC Cao, HT Han, TY Jones, RC Liu, YY Jarman, M Hardcastle, IR Giuliano, AE Cabot, MC TI Tamoxifen induces selective membrane association of protein kinase C epsilon in MCF-7 human breast cancer cells SO INTERNATIONAL JOURNAL OF CANCER LA English DT Article; Proceedings Paper CT American-Association-of-Cancer-Research Meeting CY MAR 19-24, 1996 CL WASHINGTON, D.C. SP Amer Assoc Canc Res ID PHOSPHOLIPASE-D; INHIBITION; GROWTH; PHOSPHORYLATION; TRANSLOCATION; ACTIVATION; ISOENZYMES; INDUCTION; ANALOGS AB Tamoxifen, a synthetic antiestrogen, is known for its antitumoral action in vivo; however, it is well accepted that many tamoxifen effects are elicited via estrogen receptor-independent routes. Previously, we reported that tamoxifen induces PKC translocation in fibroblasts. In the present study, we investigated the influence of tamoxifen, and several triphenylethylene derivatives, on protein kinase C (PKC) in MCF-7 human breast cancer cells. As measured by Western blot analysis, tamoxifen elicited isozyme-specific membrane association of PKC-epsilon, which was time-dependent (as early as 5 min post-treatment) and dose-dependent (5.0-20 mu M) Tamoxifen did not influence translocation of alpha, beta, gamma, delta or zeta PKC isoforms. Structure-activity relationship studies demonstrated chemical requirements for PKC-epsilon translocation, with tamoxifen, 3-OH-tamoxifen and clomiphene being active. Compounds without the basic amino side chain, such as triphenylethylene, or minus a phenyl group, such as N,N-dimethyl-2-[(4-phenylmethyl)phenoxyl]ethanamine, were not active. In vitro cell growth assays showed a correlation between agent-induced PKC-epsilon translocation and inhibition of cell growth. Exposure of cells to clomiphene resulted in apoptosis. Since PKC-epsilon has been associated with cell differentiation and cellular growth-related processes, the antiproliferative influence of tamoxifen on MCF-7 cells may be related to the interaction with PKC-E. (C) 1998 Wiley-Liss, Inc. C1 Eisenberg Keefer Breast Canc Ctr, St Johns Hlth Ctr, John Wayne Canc Inst, Santa Monica, CA 90404 USA. Canc Res Campaign, Inst Canc, Res Labs, Ctr Canc Therapeut, Sutton, Surrey, England. USN, Natl Naval Med Ctr, Dept Surg, LCDR,MC, Bethesda, MD 20084 USA. RP Cabot, MC (reprint author), Eisenberg Keefer Breast Canc Ctr, St Johns Hlth Ctr, John Wayne Canc Inst, 2200 Santa Monica Blvd, Santa Monica, CA 90404 USA. OI Liu, Yong-Yu/0000-0002-7968-0162 NR 27 TC 40 Z9 41 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0020-7136 J9 INT J CANCER JI Int. J. Cancer PD SEP 11 PY 1998 VL 77 IS 6 BP 928 EP 932 DI 10.1002/(SICI)1097-0215(19980911)77:6<928::AID-IJC22>3.0.CO;2-W PG 5 WC Oncology SC Oncology GA 110VG UT WOS:000075401400022 PM 9714066 ER PT J AU Wozniak, PR Zdziarski, AA Smith, D Madejski, GM Johnson, WN AF Wozniak, PR Zdziarski, AA Smith, D Madejski, GM Johnson, WN TI X-ray and soft gamma-ray spectra of broad-line radio galaxies SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE line : profiles; galaxies : active; galaxies : Seyfert; gamma-rays : observations; radio continuum : galaxies; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; K-ALPHA-LINES; CENTAURUS-A; COLD MATTER; SUPERLUMINAL MOTION; SEYFERT-1 GALAXIES; OSSE OBSERVATIONS; EMISSION; 3C-120; REFLECTION AB We study X-ray and soft gamma-ray spectral properties of nearby broad-line radio galaxies (BLRGs) using data from Ginga, ASCA, OSSE and EXOSAT. The X-ray spectra are well fitted by an intrinsic power-law continuum with an energy index of alpha similar to 0.7, moderately absorbed by a cold medium. In addition, the Ginga spectra show fluorescent Fe K alpha lines with an average equivalent width of similar to 100 eV, and, in some cases, Compton reflection humps. However, the latter are significantly weaker than both those seen in radio-quiet Seyfert Is and those expected if the Fe K alpha lines were due to reflection. We find that this weakness of reflection cannot be explained by dilution by another continuum component, e.g. from a jet, Some ASCA and EXOSAT spectra show soft X-ray excesses below similar to 3 keV. When that component is taken into account, the Fe Ka lines in the ASCA data are found to be unresolved in most cases, and to have equivalent widths less than or similar to 200 eV, consistent with the Ginga data. Multiple observations of 3C 382 and 390.3 show the Fe K alpha line approximately constant in flux but accompanied by strong continuum variations. This indicates the bulk of the line is formed by matter at a distance much larger than an accretion-disc scale, consistent with the ASCA line width measurements. The column density of the matter required to account for the observed line fluxes is N-H greater than or similar to 10(23) cm(-2). Such a medium is in the line of sight of 3C 445, but it has to be out of it in other objects in which the observed NH are substantially lower. Thus a cold medium with that N-H and covering a large solid angle is common in BLRGs, but in most objects it is out of the line of sight, consistent with the unified AGN model. The spectra of BLRGs break and become softer above similar to 100 keV, as shown by a simultaneous ASCA/OSSE observation of 3C 120 and by the OSSE spectra being on average much softer than the X-ray spectra. Finally, we find the X-ray and gamma-ray spectral properties of Cen A, a bright narrow-line radio galaxy - alpha similar or equal to 0.8, no or weak Compton reflection, N-H greater than or similar to 10(23) cm(-2) (which is consistent with its Fe K alpha line flux), and a high-energy break at similar to 100 keV - consistent with Cen A being intrinsically very similar to BLRGs studied here, again in agreement with the unified model. C1 Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. N Copernicus Astron Ctr, PL-00716 Warsaw, Poland. Univ Leicester, Dept Phys, Leicester LE1 7RH, Leics, England. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Wozniak, PR (reprint author), Princeton Univ, Dept Astrophys Sci, Peyton Hall, Princeton, NJ 08544 USA. RI Johnson, Neil/G-3309-2014 NR 78 TC 78 Z9 78 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD SEP 11 PY 1998 VL 299 IS 2 BP 449 EP 466 DI 10.1046/j.1365-8711.1998.01831.x PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 121NW UT WOS:000076021100019 ER PT J AU Willson, RF Redfield, SL Lang, KR Thompson, BJ St Cyr, OC AF Willson, RF Redfield, SL Lang, KR Thompson, BJ St Cyr, OC TI First VLA observations of nonthermal metric bursts associated with coronal mass ejections detected by the Solar and Heliospheric Observatory SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona; Sun : radio radiation ID NOISE STORMS; RADIO; EMISSION; WAVELENGTHS AB We present the first observations of nonthermal decimetric burst emission of the Sun using the new 400 cm (74 MHz) system at the VLA. Our VLA observations were carried out in collaboration with the Large Angle Spectroscopic Coronagraph (LASCO) and the Extreme-Ultraviolet Imaging Telescope (EIT) on board the Solar and Heliospheric Observatory spacecraft. Full-disk observations at 400 and 91 cm were used to study the spatial and temporal variations of nonthermal radio bursts during coronal mass ejections (CMEs) detected by LASCO as well as transient extreme-ultraviolet brightenings detected by the EIT. VLA snapshot maps at 400 cm revealed impulsive burst emission in the low corona that began near the estimated start time of the CME activity; that beginning also coincided with a C1.1 GOES X-ray burst and an EIT flarelike brightening. The nonthermal metric bursts then continued sporadically during the next several hours, which included the ejection of spatially separated CME components. The 400 cm bursts are contained within curved, or archlike, sources at a fixed radial distance but with a varying position between two active regions detected by the EIT near the limb, suggesting that they were emitted within large-scale magnetic loops. Our 91 cm observations also show the onset of a long-lasting type I noise storm following the initiation of CME activity, again suggesting an intimate relationship between the production of nonthermal particles and large-scale evolving plasma-magnetic field structures in the corona. C1 Tufts Univ, Dept Phys & Astron, Medford, MA 02155 USA. NASA, Goddard Space Flight Ctr, SOHO Expt Operat & Anal Facil, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, CPI, USN,Res Lab, Greenbelt, MD 20771 USA. RP Willson, RF (reprint author), Tufts Univ, Dept Phys & Astron, Medford, MA 02155 USA. RI Thompson, Barbara/C-9429-2012; OI Redfield, Seth/0000-0003-3786-3486 NR 21 TC 15 Z9 15 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD SEP 10 PY 1998 VL 504 IS 2 BP L117 EP L121 DI 10.1086/311585 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KY UT WOS:000077777700015 ER PT J AU Smith, MP Johnson, KM Zhang, M Flippen-Anderson, JL Kozikowski, AP AF Smith, MP Johnson, KM Zhang, M Flippen-Anderson, JL Kozikowski, AP TI Tuning the selectivity of monoamine transporter inhibitors by the stereochemistry of the nitrogen lone pair SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID DOPAMINE UPTAKE; LIGAND-BINDING; COCAINE; METHYLPHENIDATE; PAROXETINE; ANALOGS; ESTERS; DRUG C1 Georgetown Univ, Med Ctr, Inst Cognit & Computat Sci, Washington, DC 20007 USA. Univ Texas, Med Branch, Dept Pharmacol & Toxicol, Galveston, TX 77555 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Kozikowski, AP (reprint author), Georgetown Univ, Med Ctr, Inst Cognit & Computat Sci, Washington, DC 20007 USA. RI Johnson, Kenneth/E-7944-2014 NR 27 TC 34 Z9 34 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD SEP 9 PY 1998 VL 120 IS 35 BP 9072 EP 9073 DI 10.1021/ja981423s PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 118VA UT WOS:000075860100024 ER PT J AU Rizos, AK Ngai, KL AF Rizos, AK Ngai, KL TI Local segmental dynamics of low molecular weight polystyrene: New results and interpretation SO MACROMOLECULES LA English DT Article ID SUPERCOOLED ORTHO-TERPHENYL; MISCIBLE POLYMER BLENDS; BULK AMORPHOUS POLYMERS; SHORT-TIME DYNAMICS; VISCOELASTIC PROPERTIES; COMPONENT DYNAMICS; GLASS-TRANSITION; NEUTRON-SCATTERING; CHEMICAL-STRUCTURE; LIGHT-SCATTERING AB The molecular dynamics of an 1100 low molecular weight polystyrene are reexamined by photon correlation spectroscopy measurements. The new experimental data combined with recoverable creep compliance data taken previously on the same sample provides information on the local segmental motion in a wide time window of more than II decades. Significant reduction of the "fragility" (i.e., a scaled temperature dependence of the retardation time) of the low molecular weight polystyrene compared with high molecular weight polystyrene, seen first by Santangelo and Roland by shear modulus measurement, is confirmed. The broader time window available in the present work shows for the fu st tithe that, unlike high molecular weight polystyrene, the dispersion of the low molecular weight sample is strongly temperature dependent and narrows with increasing temperature. By considering the low molecular weight polymer as a blend of chain ends and inner repeat units, the results are interpreted by the coupling model. C1 Univ Crete, Dept Chem, Heraklion 71110, Greece. Fdn Res & Technol Hellas, Heraklion 71110, Greece. USN, Res Lab, Washington, DC 20375 USA. RP Ngai, KL (reprint author), Univ Crete, Dept Chem, POB 1527, Heraklion 71110, Greece. RI Rizos, Apostolos/F-6807-2011 NR 66 TC 28 Z9 28 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD SEP 8 PY 1998 VL 31 IS 18 BP 6217 EP 6225 DI 10.1021/ma980613k PG 9 WC Polymer Science SC Polymer Science GA 118YZ UT WOS:000075869700034 ER PT J AU Patton, DC Pederson, MR AF Patton, DC Pederson, MR TI A theoretical study of rare-gas diatomic molecules with the generalized gradient approximation to density functional theory SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article ID EXCHANGE-ENERGY; ACCURATE; FORCES; ATOMS; REPRESENTATION; BEHAVIOR AB Three popular approximations to density functional theory are used to calculate equilibrium bond lengths, atomization energies, and vibrational frequencies of 10 rare-gas diatomic molecules. We investigated the results for the local density approximation (LDA), the Perdew-Wang 91 generalized-gradient approximation (GGA-PW91), and the Perdew-Burke-Ernzerhof generalized-gradient approximation (GGA-PBE) functionals. Calculated results are well converged with respect to basis set and numerical precision. In addition, we studied the effects due to long-range 1/r(6) attractions with the London formula and density functional determined atomic polarizabilities and ionization potentials. These calculations indicate that the interaction from the overlay of atomic densities and the long-range van der Waals attraction are both important for correctly predicting the total binding energy. (C) 1998 John Wiley & Sons, Inc. Int J Quant Chem 69: 619-627, 1998. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Patton, DC (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. NR 30 TC 31 Z9 31 U1 0 U2 5 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0020-7608 EI 1097-461X J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD SEP 5 PY 1998 VL 69 IS 4 BP 619 EP 627 DI 10.1002/(SICI)1097-461X(1998)69:4<619::AID-QUA20>3.0.CO;2-T PG 9 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA 110VE UT WOS:000075401200020 ER PT J AU Clays, K Olbrechts, G Munters, T Persoons, A Kim, OK Choi, LS AF Clays, K Olbrechts, G Munters, T Persoons, A Kim, OK Choi, LS TI Enhancement of the molecular hyperpolarizability by a supramolecular amylose-dye inclusion complex, studied by hyper-Rayleigh scattering with fluorescence suppression SO CHEMICAL PHYSICS LETTERS LA English DT Article ID 2ND-HARMONIC GENERATION; HEMICYANINE; MONOLAYERS AB The first hyperpolarizability beta of a free hemicyanine dye and a homologue dye included in a supramolecular complex have been determined by hyper-Rayleigh scattering. Since the inclusion complex is fluorescent, high-frequency demodulation of the time-delayed multiphoton fluorescence has been used to retrieve a fluorescence-free inherent value for its first hyperpolarizability. The free dye does not exhibit fluorescence; the inclusion induces fluorescence with a lifetime of 4.8 +/- 0.1 ns; and the inclusion complex has a fluorescence-free value for its dispersion-free first hyperpolarizability beta(0) of approximately twice that for the free dye ((200 +/- 5) X 10(-30) vs. (100 +/- 10) X 10(-30) esu)). The enhanced polar orientation of this complex in thin films, and better thermal and mechanical stability, together with this increase in molecular nonlinearity confirm inclusion as a way to engineer efficient macroscopic arrangements for nonlinear optics. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Louvain, Dept Chem, Ctr Res Mol Elect & Photon, Lab Chem & Biol Dynam, B-3001 Louvain, Belgium. Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. USN, Div Chem, Res Lab, Washington, DC 20375 USA. RP Clays, K (reprint author), Univ Louvain, Dept Chem, Ctr Res Mol Elect & Photon, Lab Chem & Biol Dynam, Celestijnenlaan 200D, B-3001 Louvain, Belgium. NR 9 TC 51 Z9 51 U1 0 U2 5 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 SEP 4 PY 1998 VL 293 IS 5-6 BP 337 EP 342 DI 10.1016/S0009-2614(98)00795-7 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 116VP UT WOS:000075746000003 ER PT J AU Owrutsky, JC Nelson, HH Baronavski, AP Kim, OK Tsivgoulis, GM Gilat, SL Lehn, JM AF Owrutsky, JC Nelson, HH Baronavski, AP Kim, OK Tsivgoulis, GM Gilat, SL Lehn, JM TI Optical properties and dynamics of a photochromic bisthienylethene in solution and in a polymer film SO CHEMICAL PHYSICS LETTERS LA English DT Article ID NONDESTRUCTIVE READOUT METHOD; PICOSECOND LASER PHOTOLYSIS; MOLECULAR SWITCHING DEVICE; DATA STORAGE MEDIA; REVERSIBLE PHOTOCYCLIZATION; ELECTROCHEMICAL PROPERTIES; DIARYLETHENE DERIVATIVES; REFRACTIVE-INDEX; MEMORY; PHOTOSWITCH AB Optical switching dynamics and fatiguewere investigated for a photochromic molecular switch, bis(5-pyridyl-2-methylthien-3-yl)perfluorocyclopentene (PMTFC). Femtosecond transient absorption was measured using 270 nm pump and broadband visible probe pulses for samples in ethanol solution and as a dispersion film of poly(butyl acrylate-co-acrylic acid). The optical switching occurs in less than or equal to 3 ps in both cases. The spectral evolution observed in solution within 20 ps is absent in the film, suggesting that the switching dynamics are sensitive to the molecular environment. PMTFC in the copolymer film demonstrated evidence of fatigue after similar to 1500 complete cycles of optical switching. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. Coll France, F-75231 Paris 05, France. RP Owrutsky, JC (reprint author), USN, Res Lab, Div Chem, Washington, DC 20375 USA. RI GILAT, Sylvain/B-9304-2008; Owrutsky, Jeffrey/K-7649-2012 NR 28 TC 42 Z9 42 U1 0 U2 7 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 SEP 4 PY 1998 VL 293 IS 5-6 BP 555 EP 563 DI 10.1016/S0009-2614(98)00816-1 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 116VP UT WOS:000075746000036 ER PT J AU Stamper, J AF Stamper, J TI Laser-generated jets and megagauss magnetic fields SO SCIENCE LA English DT Editorial Material C1 USN, Res Lab, Washington, DC 20375 USA. RP Stamper, J (reprint author), Res Support Instruments, Lanham, MD 20706 USA. NR 5 TC 3 Z9 4 U1 0 U2 2 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD SEP 4 PY 1998 VL 281 IS 5382 BP 1469 EP 1469 DI 10.1126/science.281.5382.1469 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 116RJ UT WOS:000075738100030 ER PT J AU Patrick, HJ Chang, CC Vohra, ST AF Patrick, HJ Chang, CC Vohra, ST TI Long period fibre gratings for structural bend sensing SO ELECTRONICS LETTERS LA English DT Article ID FIBER; SENSOR AB The authors examine the changes in wavelength and attenuation of long period fibre gratings subjected to bends with curvatures from 0 to 4.4m(-1). The wavelength change with curvature is nonlinear, with a projected minimum detectable curvature change of 2 x 10(-3)m(-1). The magnitude of the bend-induced wavelength shift depends on the rotation of the cylindrical fibre relative to the bending plane. C1 USN, Res Lab, Opt Tech Branch, Washington, DC 20375 USA. Univ Res Fdn, Greenbelt, MD 20770 USA. RP Patrick, HJ (reprint author), USN, Res Lab, Opt Tech Branch, Code 5673, Washington, DC 20375 USA. NR 9 TC 162 Z9 172 U1 1 U2 12 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD SEP 3 PY 1998 VL 34 IS 18 BP 1773 EP 1775 DI 10.1049/el:19981237 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 122CP UT WOS:000076053500046 ER PT J AU Chang, CC Vohra, ST AF Chang, CC Vohra, ST TI Spectral broadening due to non-uniform strain fields in fibre Bragg grating based transducers SO ELECTRONICS LETTERS LA English DT Article AB An experimental investigation of strain gradient induced spectral broadening in fibre Bragg grating (FBG) based transducers is carried out. Closed form analytical results describing measurand induced strain gradients in circular geometry transducers are derived, which allow experimental demonstration of novel FBG bonding approaches which eliminate spectral broadening and should lead to the development of advanced FBG based transducers. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Chang, CC (reprint author), USN, Res Lab, Div Opt Sci, Code 5673, Washington, DC 20375 USA. NR 4 TC 7 Z9 7 U1 0 U2 1 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD SEP 3 PY 1998 VL 34 IS 18 BP 1778 EP 1779 DI 10.1049/el:19981259 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 122CP UT WOS:000076053500049 ER PT J AU Sims, JR Hanson, EL AF Sims, JR Hanson, EL TI Thromboangiitis obliterans (Buerger's disease) SO NEW ENGLAND JOURNAL OF MEDICINE LA English DT Article C1 USN Submarine, Med Res Lab, Groton, CT 06349 USA. RP Sims, JR (reprint author), USN Submarine, Med Res Lab, Groton, CT 06349 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU MASS MEDICAL SOC PI BOSTON PA 10 SHATTUCK, BOSTON, MA 02115 USA SN 0028-4793 J9 NEW ENGL J MED JI N. Engl. J. Med. PD SEP 3 PY 1998 VL 339 IS 10 BP 672 EP 672 DI 10.1056/NEJM199809033391005 PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA 115WA UT WOS:000075688100005 PM 9725925 ER PT J AU Consolazio, GR McVay, MC Rish, JW AF Consolazio, GR McVay, MC Rish, JW TI Measurement and prediction of pore pressures in saturated cement mortar subjected to radiant heating SO ACI MATERIALS JOURNAL LA English DT Article DE heat transfer; radiant heating; safely; spalling; thermal analysis ID CONCRETE AB saturated (or partially saturated) porous medium is subjected to a high temperature heating source, pore pressures large enough to initiate explosive spalling carl be developed,within the pore spaces of the material. The level to which these pore pressures ultimately rise depends on the saturation and permeability of the medium as well as the rate at which heal flows into the material. bt this paper; experimental and numerical studies involving the measurement and prediction of pore pressures in porous media are presented. Pore pressure data are presented Sor experimental tests in which saturated cement mortar specimens were subjected to high temperature radiant heating conditions. A numerical modeling technique is then presented and is used to numerically simulate the experimental work. Close agreement is shown between the pore pressures and temperatures recorded experimentally and those predicted through simulation. C1 Univ Florida, Gainesville, FL 32611 USA. USN, Nonacoust Sensing Branch, Ctr Surface Warfare, Coastal Syst Stn, Panama City, FL USA. RP Consolazio, GR (reprint author), Univ Florida, Gainesville, FL 32611 USA. NR 12 TC 29 Z9 33 U1 1 U2 1 PU AMER CONCRETE INST PI FARMINGTON HILLS PA 38800 COUNTRY CLUB DR, FARMINGTON HILLS, MI 48331 USA SN 0889-325X J9 ACI MATER J JI ACI Mater. J. PD SEP-OCT PY 1998 VL 95 IS 5 BP 525 EP 536 PG 12 WC Construction & Building Technology; Materials Science, Multidisciplinary SC Construction & Building Technology; Materials Science GA 128WP UT WOS:000076431600004 ER PT J AU Sarpkaya, T AF Sarpkaya, T TI Decay of wake vortices of large aircraft SO AIAA JOURNAL LA English DT Article ID TRAILING VORTEX; TURBULENCE; SURFACE; WAVES AB A brief summary of previous works is followed by an in-depth analysis of velocities, circulations, and decay histories of a number of trailing vortices generated by large aircraft during field tests in Memphis, Tennessee. The results suggest that the decay of trailing vortices is governed by the mutual straining of vortices; intermittent exchange of mass, momentum, and vorticity across the core boundary; rotational damping and restructuring of turbulence in the core; stretching of large turbulent structures, turbulent diffusion, and the interaction of oppositely signed vorticity in the overlapping regions of the vortex pair; and the draining of vorticity from the Kelvin oval. C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. RP Sarpkaya, T (reprint author), USN, Postgrad Sch, Dept Mech Engn, 700 Dyer Rd, Monterey, CA 93943 USA. EM Sarp@nps.navy.mil NR 39 TC 23 Z9 23 U1 1 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD SEP PY 1998 VL 36 IS 9 BP 1671 EP 1679 DI 10.2514/2.570 PG 9 WC Engineering, Aerospace SC Engineering GA 114QM UT WOS:000075620400016 ER PT J AU Kang, YK Park, HC Agrawal, B AF Kang, YK Park, HC Agrawal, B TI Optimization of piezoceramic sensor/actuator placement for vibration control of laminated plates SO AIAA JOURNAL LA English DT Article C1 Univ Manchester, Dept Mech Engn, Manchester M13 9PL, Lancs, England. Pusan Natl Univ, Sch Mech Engn, Pusan 609735, South Korea. USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Kang, YK (reprint author), Univ Manchester, Dept Mech Engn, Manchester M13 9PL, Lancs, England. NR 5 TC 11 Z9 11 U1 0 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD SEP PY 1998 VL 36 IS 9 BP 1763 EP 1765 DI 10.2514/2.7558 PG 3 WC Engineering, Aerospace SC Engineering GA 114QM UT WOS:000075620400039 ER PT J AU Kayar, SR Miller, TL Wolin, MJ Aukhert, EO Axley, MJ Kiesow, LA AF Kayar, SR Miller, TL Wolin, MJ Aukhert, EO Axley, MJ Kiesow, LA TI Decompression sickness risk in rats by microbial removal of dissolved gas SO AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY LA English DT Article DE biochemical decompression; hydrogen diving; hydrogen metabolism; hyperbaria; methane; methanogens ID HYDROGEN; ANAEROBES; TISSUES; HELIUM AB We present a method for reducing the risk of decompression sickness (DCS) in rats exposed to high pressures of H-2 Suspensions of the human colonic microbe Methanobrevibacter smithii were introduced via a colonic cannula into the large intestines of the rats. While the rats breathed H-2 in a hyperbaric chamber, the microbe metabolized some of the H-2 diffusing into the intestine, converting H-2 and CO2 to methane and water. Rate of release of methane from the rats, which was monitored by gas chromatography, varied with chamber H-2 pressure. This rate was higher during decompression than during compression, suggesting that during decompression the microbe was metabolizing H-2 stored in the rats' tissues. Rats treated with M. smithii had a 25% (5 of 20) incidence of DCS, which was significantly lower (P < 0.01) than the 56% (28 of 50) incidence of untreated controls, brought on by a standardized compression and decompression sequence. Thus using a microbe in the intestine to remove an estimated 5% of the body burden of H-2 reduced DCS risk by more than one-half. This method of biochemical decompression may potentially facilitate human diving. C1 USN, Med Res Inst, Natl Naval Med Ctr, Bethesda, MD 20889 USA. New York State Dept Hlth, Wadsworth Ctr Labs & Res, Albany, NY 12237 USA. RP Kayar, SR (reprint author), USN, Med Res Inst, Natl Naval Med Ctr, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 15 TC 16 Z9 16 U1 0 U2 0 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0363-6119 J9 AM J PHYSIOL-REG I JI Am. J. Physiol.-Regul. Integr. Comp. Physiol. PD SEP PY 1998 VL 275 IS 3 BP R677 EP R682 PG 6 WC Physiology SC Physiology GA 117VC UT WOS:000075802500005 PM 9728062 ER PT J AU Fattorini, HO Sritharan, SS AF Fattorini, HO Sritharan, SS TI Optimal control problems with state constraints in fluid mechanics and combustion SO APPLIED MATHEMATICS AND OPTIMIZATION LA English DT Article DE distributed parameter systems; optimal controls; state constraints; fluid flow control; combustion control ID DISTRIBUTED-PARAMETER SYSTEMS; VISCOUS-FLOW PROBLEMS; ELLIPTIC-EQUATIONS; STOKES OPERATOR; SPACES; EXISTENCE; LR AB Using nonlinear programming theory in Banach spaces we derive a version of Pontryagin's maximum principle that can be applied to distributed parameter systems under control and state constrains. The results are applied to fluid mechanics and combustion problems. C1 Univ Calif Los Angeles, Dept Math, Los Angeles, CA 90095 USA. USN, Command Control & Ocean Surveillance Ctr, San Diego, CA 92152 USA. RP Fattorini, HO (reprint author), Univ Calif Los Angeles, Dept Math, Los Angeles, CA 90095 USA. OI Sritharan, Sivaguru/0000-0003-2845-332X NR 47 TC 14 Z9 14 U1 0 U2 2 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0095-4616 J9 APPL MATH OPT JI Appl. Math. Optim. PD SEP-OCT PY 1998 VL 38 IS 2 BP 159 EP 192 DI 10.1007/s002459900087 PG 34 WC Mathematics, Applied SC Mathematics GA ZV369 UT WOS:000074297700003 ER PT J AU Lambrakos, SG Trzaskoma-Paulette, PP Triandaf, IA AF Lambrakos, SG Trzaskoma-Paulette, PP Triandaf, IA TI Surface-site charge-displacement model for analysis of electromodulated optical second-harmonic response at a metal surface SO APPLIED SPECTROSCOPY LA English DT Article DE second-harmonic response analysis; metal/electrode interfaces; second-harmonic generation; interfacial structural information ID FILM SILVER ELECTRODES; 2ND-HARMONIC GENERATION; INTERFACE AB We present an analysis of second-harmonic (SH) response from metal surfaces that is based on a model representation whose associated parameters are defined in terms of nonlinear polarizabilities originating from charge displacement occurring on a molecular level. Our analysis suggests that the general functional dependence of SH response at a metal/electrolyte interface on the time-independent (dc) electric field is typically different from that implied by previous models. The analysis shows that our model representation is sufficiently general for extracting features from second-harmonic generation (SHG) data in order to analyze such data by methods based on system identification and pattern recognition. Our model, which is based on a classical representation of the nonlinear response of bound (or constrained) charge, is found to be consistent with trends observed in experimental measurements of second-harmonic response as a function of surface charge density, The results of this analysis suggest that SH data are relatively rich in terms of features that can be correlated with local surface structure and that the data should be interpreted by means of a more general model representation than has been previously proposed. C1 USN, Div Mat Sci & Technol, Res Lab, Washington, DC 20375 USA. USN, Div Plasma Phys, Res Lab, Washington, DC 20375 USA. RP Trzaskoma-Paulette, PP (reprint author), USN, Div Mat Sci & Technol, Res Lab, Washington, DC 20375 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD SEP PY 1998 VL 52 IS 9 BP 1240 EP 1247 DI 10.1366/0003702981945066 PG 8 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 127VW UT WOS:000076372100017 ER PT J AU Little, RD AF Little, RD TI Making the corps. SO ARMED FORCES & SOCIETY LA English DT Book Review C1 USN Acad, Dept Econ, Annapolis, MD 21402 USA. RP Little, RD (reprint author), USN Acad, Dept Econ, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU TRANSACTION PERIOD CONSORTIUM PI NEW BRUNSWICK PA DEPT 3091 RUTGERS-THE STATE UNIV OF NJ, NEW BRUNSWICK, NJ 08903 USA SN 0095-327X J9 ARMED FORCES SOC JI Armed Forces Soc. PD FAL PY 1998 VL 25 IS 1 BP 166 EP 171 DI 10.1177/0095327X9802500112 PG 6 WC Political Science; Sociology SC Government & Law; Sociology GA 146NM UT WOS:000077437200010 ER PT J AU Kasif, S Salzberg, S Waltz, D Rachlin, J Aha, DW AF Kasif, S Salzberg, S Waltz, D Rachlin, J Aha, DW TI A probabilistic framework for memory-based reasoning SO ARTIFICIAL INTELLIGENCE LA English DT Article DE learning; probabilistic inference; meta-learning; local learning; MBR transform; memory-based learning; Bayes networks ID PROTEIN SECONDARY STRUCTURE; NEAREST-NEIGHBOR ALGORITHM; STRUCTURE PREDICTION AB In this paper, we propose a probabilistic framework for memory-based reasoning (MBR). The framework allows us to clarify the technical merits and limitations of several recently published MBR methods and to design new variants. The proposed computational framework consists of three components: a specification language to define an adaptive notion of relevant context for a query; mechanisms for retrieving this context; and local learning procedures that are used to induce the desired action from this context. We primarily focus on actions in the form of a classification. Based on the framework we derive several analytical and empirical results that shed light on MBR algorithms. We introduce the notion of an MBR transform, and discuss its utility for learning algorithms. We also provide several perspectives on memory-based reasoning from a multi-disciplinary point of view. (C) 1998 Published by Elsevier Science B.V. C1 Univ Illinois, Dept Elect Engn & Comp Sci, Chicago, IL 60607 USA. Johns Hopkins Univ, Dept Comp Sci, Baltimore, MD 21210 USA. NEC Res Inst, Princeton, NJ 08540 USA. IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. USN, Res Lab, Navy Ctr Appl Res AI, Washington, DC 20375 USA. RP Kasif, S (reprint author), Univ Illinois, Dept Elect Engn & Comp Sci, Chicago, IL 60607 USA. EM kasif@cs.jhu.edu; salzberg@cs.jhu.edu; waltz@research.nj.nec.com; rachlin@cs.jhu.edu; aha@aic.nrl.navy.mil RI Salzberg, Steven/F-6162-2011 OI Salzberg, Steven/0000-0002-8859-7432 NR 48 TC 15 Z9 15 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0004-3702 J9 ARTIF INTELL JI Artif. Intell. PD SEP PY 1998 VL 104 IS 1-2 BP 287 EP 311 DI 10.1016/S0004-3702(98)00046-0 PG 25 WC Computer Science, Artificial Intelligence SC Computer Science GA 136ZY UT WOS:000076890000007 ER PT J AU Stone, RC AF Stone, RC TI CCD positions for the outer planets in 1996-1997 determined in the extragalactic reference frame SO ASTRONOMICAL JOURNAL LA English DT Article DE astrometry; planets and satellites : individual (Uranus, Neptune, Pluto) AB This paper presents 316 new equatorial positions for the planets Uranus, Neptune, and Pluto obtained in 1996-1997 with the Flagstaff Astrometric Scanning Transit Telescope (FASTT). All the positions were determined in the extragalactic reference frame using CCD observations and are accurate to similar to +/-0." 2 in each coordinate. When these positions are compared with the latest JPL ephemerides (DE405), there is generally good agreement between the observed and calculated positions for these planets. In particular, the offset in the declination of Pluto (Delta delta similar to 0." 1) is no longer evident, and consequently, the DE405 is obviously an improvement over its predecessor, the DE403, in that respect. There appears to be a small offset, similar to 0." 09, however, in the right ascensions of Uranus, which might be accidental or caused by errors in the FASTT observed or DE405 calculated ephemeris positions; future observations are planned to clarify this issue. With the release of the Hipparcos Tycho, and ACT catalogs of extremely accurate reference star positions, it is now possible for telescopes, such as the FASTT, to determine the positions of planets and their satellites directly in the international celestial reference frame (ICRF) with greatly improved accuracy (similar to +/-0." 06) in each coordinate. All future FASTT observations will be made in this manner, and the FASTT observing program will be expanded to include satellites of planets as well. C1 USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. RP Stone, RC (reprint author), USN Observ, Flagstaff Stn, POB 1149, Flagstaff, AZ 86002 USA. EM rcs@nofs.navy.mil NR 18 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD SEP PY 1998 VL 116 IS 3 BP 1461 EP 1469 DI 10.1086/300507 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 121XG UT WOS:000076040700039 ER PT J AU Goetz, JA Pipher, JL Forrest, WJ Watson, DM Raines, SN Woodward, CE Greenhouse, MA Smith, HA Hughes, VA Fischer, J AF Goetz, JA Pipher, JL Forrest, WJ Watson, DM Raines, SN Woodward, CE Greenhouse, MA Smith, HA Hughes, VA Fischer, J TI Cepheus A East: Unraveling the mysteries SO ASTROPHYSICAL JOURNAL LA English DT Article DE H II regions; infrared : stars; ISM : individual (Cepheus A East); ISM : molecules; stars : formation; stars : pre-main-sequence ID STAR-FORMING REGION; HERBIG-HARO OBJECTS; THERMAL RADIO JET; NEAR-INFRARED EMISSION; MOLECULAR OUTFLOWS; REFLECTION NEBULAE; VELOCITY; CLOUDS; POLARIMETRY; ARRAYS AB New infrared images of Cep A East are presented that show two regions of shock-excited line emission from separate bipolar hows. We identify the dominant sources powering the outflows and argue that the results support a multiple outflow model (Narayanan gr Walker) as opposed to a quadrupolar outflow scenario. The images include near-infrared broadband (jr [2.158 mu m], L " [3.81 mu m], and M' [4.67 mu m]) and spectral line ([Fe II] emission line at 1.644 mu m and H-2 1-0 S[1] line at 2.122 mu m) observations, as well as continuum emission, at 1.644 mu m and 2.122 mu m. Considering our data and other results, we present a unified, self-consistent picture of the disk and shock structure. The northern emission region appears to be the result of the ablation of a dense molecular clump (coincident with HW 6) in the path of a diverting jet from YSO HW 2 and subsequent multiple bow shocks with prompt entrainment arising from the interaction of the jet with the molecular cloud Cep A-2. The southern line emission region near HW 7 resembles the "artillery shell" bow shocks found in Orion and is most likely a J-type shock caused by a jet from another YSO, possibly HW 3(d)ii. C1 Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Univ Rochester, CEK Mees Observ, Rochester, NY 14627 USA. Univ Wyoming, Wyoming Infrared Observ, Dept Phys & Astron, Laramie, WY 82071 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Queens Univ, Dept Phys, Astron Grp, Kingston, ON K7L 3N6, Canada. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Goetz, JA (reprint author), Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. NR 69 TC 28 Z9 28 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD SEP 1 PY 1998 VL 504 IS 1 BP 359 EP 374 DI 10.1086/306058 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KT UT WOS:000077777200030 ER PT J AU Doschek, GA Laming, JM Feldman, U Wilhelm, K Lemaire, P Schuhle, U Hassler, DM AF Doschek, GA Laming, JM Feldman, U Wilhelm, K Lemaire, P Schuhle, U Hassler, DM TI The Si/Ne abundance ratio in polar coronal hole and quiet-Sun coronal regions SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : abundances; Sun : corona; Sun : UV radiation ID UPPER SOLAR ATMOSPHERE; ELEMENTAL ABUNDANCES; SUMER TELESCOPE; SPECTROMETER; DIAGNOSTICS; SPECTRA; SOHO; TEMPERATURES; IONIZATION AB Using spectra obtained from the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer flown on the Solar and Heliospheric Observatory (SOHO) spacecraft, we determine the Si/Ne abundance ratio in diffuse, interplume polar coronal hole regions, as well as the ratio relative to quiet-Sun coronal regions. Ne has the second highest first ionization potential (FIP) of solar abundant elements, and Si is a low-FIP element. Thus the Si/Ne ratio is a sensitive indicator of abundance variations due to the FIP effect. We develop new spectroscopic diagnostics for the determination of the Si/Ne abundance ratio. Assuming ionization equilibrium, we find that the Si/Ne abundance ratio in interplume polar coronal hole regions is about a factor of 2 greater than the photospheric value and is close to or the same as in coronal quiet-Sun regions. This result pertains to the electron temperature range 5-8 x 10(5) K. However, the combined atomic physics, instrumental, and statistical uncertainty in this result is about a factor of 2, and therefore this observed enhancement is consistent with no enhancement in the polar hole abundances. Nevertheless, our results follow the same trend, i.e., a greater than photospheric abundance ratio of low-FIP elements in the corona relative to high-FIP elements, as found from other abundance measurements in the corona that involve different atomic physics and different instruments. Therefore we feel that our results reflect an actual abundance enhancement, despite being within an uncertainty level bar that encompasses photospheric abundances. We also examine the Ne/Mg abundance ratio over a 24.5 hr observation and find no significant abundance variations. (Mg is a low-FIP element.) Thus, no large transient abundance variations appear to occur on timescales shorter than about a day, although this result is based on only one observation. From lines of Mg vn, Mg vm, Mg Ix, and Mg x we find that the electron temperature along the line of sight increases with height above the limb over the polar coronal holes, as has been previously reported. We determine the emission measure distribution as a function of height from Mg VII, Mg vm, and Mg x lines. We determine average temperatures along the line of sight over the polar holes from Ne VIII/Ne VII, Mg VIII/Mg VII, and Si VIII/Si VII line ratios. We also discuss the temperature properties of the coronal hole and quiet-Sun regions using forbidden lines of Fe x and Fe XI. We comment on the possibility that ionization equilibrium is not valid in polar coronal hole regions, a possible scenario in light of recent observations that show outflows in coronal holes beginning at about the temperature of formation of Ne VIII. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. Univ Paris 11, CNRS, Unite Mixte, Inst Astrophys Spatiale, F-91405 Orsay, France. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. SW Res Inst, Boulder, CO 80302 USA. RP Doschek, GA (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 33 TC 28 Z9 28 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD SEP 1 PY 1998 VL 504 IS 1 BP 573 EP 587 DI 10.1086/306043 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KT UT WOS:000077777200048 ER PT J AU Luhman, ML Satyapal, S Fischer, J Wolfire, MG Cox, P Lord, SD Smith, HA Stacey, GJ Unger, SJ AF Luhman, ML Satyapal, S Fischer, J Wolfire, MG Cox, P Lord, SD Smith, HA Stacey, GJ Unger, SJ TI Infrared Space Observatory measurements of a [C II] 158 micron line deficit in ultraluminous infrared galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : ISM; galaxies : starburst; infrared : galaxies; infrared : ISM : lines and bands; ISM : atoms ID LONG-WAVELENGTH SPECTROMETER; PHOTODISSOCIATION REGIONS; INTERSTELLAR-MEDIUM; GALACTIC NUCLEI; MOLECULAR GAS; EMISSION; SPECTROSCOPY; TRANSITION; ORIGIN; FIELD AB We report measurements of the [C II] 157.74 mu m fine-structure line in a sample of seven ultraluminous infrared galaxies (ULIGs) (L-1R > 10(12) L-.) with the Long Wavelength Spectrometer on the Infrared Space Observatory. The [C II] line is an important coolant in galaxies and arises in interstellar gas exposed to far-ultraviolet photons (hv greater than or equal to 11.26 eV); in ULIGs, this radiation stems from the bursts of star formation and/or from the active galactic nuclei that power the tremendous infrared luminosity. The [C II] 158 mu m line is detected in four of the seven ULIGs; the absolute line flux (about a few times 10(-20) W cm(-2)) represents some of the faintest extragalactic [C II] emission yet observed. Relative to the far-infrared continuum, the [C II] flux from the observed ULIGs is similar to 10% of that seen from nearby normal and starburst galaxies. We discuss possible causes for the [C II] deficit, namely (1) self-absorbed or optically thick [C II] emission, (2) saturation of the [C II] emission in photodissociated gas with high gas density n (much greater than 3 x 10(3) cm(-3)) or with a high ratio of incident W flux G(o) to n (G(o)/n greater than or similar to 10 cm(3)), or (3) the presence of a soft ultraviolet radiation field caused, for example, by a stellar population deficient in massive main-sequence stars. As nearby examples of colliding galaxies, ULIGs may resemble high-redshift protogalaxies in both morphology and spectral behavior. If true, the suggested [C II] deficit in ULIGs poses limitations on the detection rate of high-z sources and on the usefulness of [C II] as an eventual tracer of protogalaxies. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Towson State Univ, Dept Phys, Towson, MD 21252 USA. Univ Paris 11, Inst Astrophys Spatiale, Orsay, France. CALTECH, IPAC, Pasadena, CA 91125 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Univ London Queen Mary & Westfield Coll, London, England. RP Luhman, ML (reprint author), USN, Res Lab, Remote Sensing Div, Code 7217, Washington, DC 20375 USA. NR 48 TC 120 Z9 120 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD SEP 1 PY 1998 VL 504 IS 1 BP L11 EP L15 DI 10.1086/311562 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KV UT WOS:000077777400003 ER PT J AU Joseph, T Lazio, W Cordes, JM AF Joseph, T Lazio, W Cordes, JM TI Hyperstrong radio-wave scattering in the Galactic center. I. A survey for extragalactic sources seen through the Galactic center SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE Galaxy, center; ISM, general; quasars, general; radio continuum, ISM scattering; surveys ID ANISOTROPIC MAGNETOGASDYNAMIC TURBULENCE; SAGITTARIUS A-ASTERISK; SOURCE SGR-A; INTERSTELLAR-MEDIUM; MAGNETOHYDRODYNAMIC TURBULENCE; DENSITY-FLUCTUATIONS; ALFVENIC TURBULENCE; FREE-ELECTRONS; CENTER REGION; PLANE AB The scattering diameters of Sgr A* and several nearby OH masers (approximate to 1" at 1 GHz) indicate that a region of enhanced scattering is along the line of sight to the Galactic center (GC). The scattering diameter of an extragalactic source seen through this scattering region will be larger by the ratio of the Sun-GC distance to the GC-scattering region separation. This ratio could be a factor of a few, if the scattering region is far from the GC and only a random superposition with it, to more than 100, if the scattering region is within the GC. We have used the VLA to survey 10 (11) fields at 20 cm (6 cm) that are between 7' and 137' from Sgr A*. Our objective was to identify extragalactic sources and measure their scattering diameters so as to constrain the GC-scattering region separation. In order to find sources within these fields, we have employed pdfCLEAN, a source detection algorithm in which sources are identified in an image by comparing the intensity histogram of the image to that expected from a noise-only image. We found over 100 sources, with the faintest sources being approximately 3 mJy. The average number of sources per field is approximately 10, though fields close to Sgr A* tend to contain fewer sources. In a companion paper we combine our survey with previous observations of the GC, and we assess the likelihood that the scattering region is so close to the GC that the resulting scattering diameters cause extragalactic sources to be resolved out by our observations. A number of Galactic sources ale included in our source catalog. We discuss the double-lobed source 1LC 359.872 + 0.178, potentially an X-ray quiet version of 1E 1740.7 - 2942, a shell-like structure with a central point source, and a possible radio transient. C1 USN, Res Lab, Washington, DC 20375 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Cornell Univ, Natl Astron & Ionosphere Ctr, Ithaca, NY 14853 USA. RP Joseph, T (reprint author), USN, Res Lab, Code 7210, Washington, DC 20375 USA. NR 53 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD SEP PY 1998 VL 118 IS 1 BP 201 EP 216 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 119UE UT WOS:000075915400004 ER PT J AU Armstrong, CR Erikson, NS AF Armstrong, CR Erikson, NS TI Right axis deviation as a criterion for echocardiographic evaluation of aircrew candidates SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article AB Background Significant pressures exist in the resource-limited environment of military aviation to select only those candidates for flight training who are both physically able to withstand the demands of the flight environment and likely to complete a career in aviation. As medical technology has advanced, uncertainty has arisen regarding the appropriate use of additional studies in the screening of aircrew candidates. At the Naval Operational Medicine Institute (NOMI), where all U.S. Navy aviation duty candidates' medical qualifications are reviewed, current policy is to perform 2-echocardiography on all candidates who exhibit a right axis deviation of +95 degrees or greater on their initial electrocardiogram. Methods: The records of all aircrew candidates referred to the Department of Internal Medicine for evaluation of right axis deviation during the years 1993, 1994, and 1995 were reviewed. A cost benefit analysis was performed to assess the cost effectiveness of using echocardiography to screen candidates suspected of having disqualifying physical defects based on a finding of right axis deviation on electrocardiogram. Results: Of the 69 cases reviewed, only 1 candidate was disqualified due to cardiovascular disease. He suffered from a large atria[ septal defect initially discovered on physical examination. Conclusions: It is not cost effective to use 2D-echocardiography to screen aircrew candidates for disqualifying cardiac defects based on a finding of a right axis deviation of +95 degrees or greater on electrocardiogram. C1 USN, Operat Med Inst, Pensacola, FL 32508 USA. RP Armstrong, CR (reprint author), USN, Operat Med Inst, Code 32R,220 Hovey Rd,Suite A, Pensacola, FL 32508 USA. NR 8 TC 0 Z9 0 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 SEP PY 1998 VL 69 IS 9 BP 833 EP 836 PG 4 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 115CU UT WOS:000075646600001 PM 9737752 ER PT J AU Margulies, SS Yuan, Q Guccione, SJ Weiss, MS AF Margulies, SS Yuan, Q Guccione, SJ Weiss, MS TI Kinematic response of the neck to voluntary and involuntary flexion SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID CERVICAL-SPINE; NORMAL RANGE; MOTION AB Methods: The dynamic head-neck responses of human subjects and cadavers undergoing involuntary impact loading conditions have been studied extensively in order to define the kinematics of the neck undergoing rapid movements, but little detailed information is available regarding slower, voluntary motions. In this study, the dynamic kinematics of head/neck complex during subject-controlled, or voluntary head motion have been investigated to compare with the kinematics to involuntary response. Five male human subjects experienced two-types of posterior/ anterior neck flexion: flexion initiated under their own volition, and flexion in response to -15Gx acceleration of the torso. Tri-axial photo target mounts were placed on a custom-fit plate at the mouth, on the first thoracic vertebra, and on the sled. High speed movie cameras captured the photo target motion. Linear and angular displacement and velocity of the head and T1 and sled were computed using customized data-processing software. The neck kinematics were represented by a 2-pin linkage which connected the anatomical origins of the head and T1. Results: The results show that maximum neck flexion relative to the torso was not significantly different between the voluntary and involuntary head motions, but that the head motion was significantly greater during the involuntary sled maneuvers. Maximum flexion velocities of 450 and 1236 degrees.s(-1) were sustained during the voluntary and involuntary maneuvers, respectively. Conclusion: These findings are important in understanding the kinematics of the human head/neck complex undergoing rapid and slow movements, and will be valuable in future studies determining a realistic physiological performance corridor for the human neck. C1 Univ Penn, Dept Bioengn, Philadelphia, PA 19104 USA. USN, Biodynam Lab, New Orleans, LA USA. RP Margulies, SS (reprint author), Univ Penn, Dept Bioengn, 105 Hayden Hall,220 S 33rd St, Philadelphia, PA 19104 USA. NR 31 TC 1 Z9 1 U1 0 U2 2 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 SEP PY 1998 VL 69 IS 9 BP 896 EP 903 PG 8 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 115CU UT WOS:000075646600012 PM 9737763 ER PT J AU Gluckman, BJ So, P Netoff, TI Spano, ML Schiff, SJ AF Gluckman, BJ So, P Netoff, TI Spano, ML Schiff, SJ TI Stochastic resonance in mammalian neuronal networks SO CHAOS LA English DT Article ID APPLIED ELECTRIC-FIELDS; CRAYFISH MECHANORECEPTORS; SIGNAL-TRANSDUCTION; HIPPOCAMPAL SLICES; INTERNAL NOISE; SYSTEMS; INFORMATION; MODEL; TRANSMISSION; DISTRIBUTIONS AB We present stochastic resonance observed in the dynamics of neuronal networks from mammalian brain. Both sinusoidal signals and random noise were superimposed into an applied electric field. As the amplitude of the noise component was increased, an optimization (increase then decrease) in the signal-to-noise ratio of the network response to the sinusoidal signal was observed. The relationship between the measures used to characterize the dynamics is discussed. Finally, a computational model of these neuronal networks that includes the neuronal interactions with the electric field is presented to illustrate the physics behind the essential features of the experiment. (C) 1998 American Institute of Physics. C1 George Mason Univ, Dept Phys & Astron, Fairfax, VA 22030 USA. George Mason Univ, Krasnow Inst Adv Studies, Fairfax, VA 22030 USA. George Washington Univ, Program Neurosci, Washington, DC 20052 USA. USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. George Mason Univ, Dept Pathol, Fairfax, VA 22030 USA. RP Gluckman, BJ (reprint author), George Mason Univ, Dept Phys & Astron, Fairfax, VA 22030 USA. EM BGluckma@GMU.edu RI Spano, Mark/B-6883-2011; OI Gluckman, Bruce/0000-0001-7695-2225 NR 55 TC 18 Z9 18 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1054-1500 J9 CHAOS JI Chaos PD SEP PY 1998 VL 8 IS 3 BP 588 EP 598 DI 10.1063/1.166340 PG 11 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 119LT UT WOS:000075898400007 ER PT J AU Dolnik, M Bollt, EM AF Dolnik, M Bollt, EM TI Communication with chemical chaos in the presence of noise SO CHAOS LA English DT Article ID BELOUSOV-ZHABOTINSKII REACTION; SYNCHRONIZATION; IMPURITIES AB We use control of chaos to encode information into the oscillations of the Belousov-Zhabotinsky reaction. An arbitrary binary message is encoded by forcing the chaotic oscillations to follow a specified trajectory. The information manipulating control requires only small perturbations to vary the binary message. In this paper we extend our recent theoretical work [Bollt and Dolnik, Phys. Rev. E 64, 1196 (1990)] by introducing anew and simplified encoding technique which can be utilized in the presence of experimental noise. We numerically and theoretically study several practical aspects of controlling symbol dynamics including: modeling noisy time-series, learning underlying symbol dynamics, and evaluation of derivatives for control by observing system responses to an intelligent and deliberate sequence of input parameter variations. All of the modeling techniques incorporated here are ultimately designed to learn and control symbol dynamics of experimental data known only as an observed time-series;the simulation assumes no global model. We find that noise affects reliability of encoding information and may cause coding errors. But, if the level of noise is confined to relatively small values, which are achievable in experiments, the control mechanism is robust to the noise. Thus we can still produce a desired symbolic code. However, scarce errors in encoding may occur due to rare but large fluctuations. These errors may be corrected during the decoding process by a variation of the filtering technique suggested by Rosa et al. (C) 1998 American Institute of Physics. C1 Brandeis Univ, Dept Chem, Waltham, MA 02254 USA. Brandeis Univ, Ctr Complex Syst, Waltham, MA 02254 USA. USN Acad, Dept Math, Annapolis, MD 21402 USA. RP Dolnik, M (reprint author), Brandeis Univ, Dept Chem, Waltham, MA 02254 USA. NR 21 TC 22 Z9 22 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1054-1500 J9 CHAOS JI Chaos PD SEP PY 1998 VL 8 IS 3 BP 702 EP 710 DI 10.1063/1.166353 PG 9 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 119LT UT WOS:000075898400020 ER PT J AU Little, BJ Ray, RI Wagner, PA AF Little, BJ Ray, RI Wagner, PA TI Tame microbiologically influenced corrosion SO CHEMICAL ENGINEERING PROGRESS LA English DT Article ID MILD-STEEL AB MIC occurs in storage and operating systems for metals exposed to various waters, process chemicals, foodstuffs, crude and distillate fuels, human plasma, and sewage. Here is a guide to understanding and managing this phenomenon. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Little, BJ (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 14 TC 2 Z9 2 U1 0 U2 0 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0360-7275 J9 CHEM ENG PROG JI Chem. Eng. Prog. PD SEP PY 1998 VL 94 IS 9 BP 51 EP 60 PG 10 WC Engineering, Chemical SC Engineering GA 122AF UT WOS:000076047700017 ER PT J AU Anderson, GP King, KD Cao, LK Jacoby, M Ligler, FS Ezzell, J AF Anderson, GP King, KD Cao, LK Jacoby, M Ligler, FS Ezzell, J TI Quantifying serum antiplague antibody with a fiber-optic biosensor SO CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY LA English DT Article ID YERSINIA-PESTIS; PLAGUE; CALIFORNIA; SURVEILLANCE; CATS AB The fiber-optic biosensor, originally developed to detect hazardous biological agents such as protein toxins or bacterial cells, has been utilized to quantify the concentration of serum antiplague antibodies. This biosensor has been used to detect and quantify the plague fraction I antigen in serum, plasma, and whole-blood samples, but its ability to quantify serum antibodies has not been demonstrated. By using a competitive assay, the concentration of serum antiplague antibodies was ascertained in the range of 2 to 15 mu g/ml. By making simple dilutions, concentrations for 11 serum samples whose antiplague antibody concentrations were unknown were determined and were found to be in good agreement with enzyme-linked immunosorbent assay results. The competitive assay method could be used to effectively determine the exposure to plague of animals or humans or could be applied to other diseases, such as hepatitis or AIDS, where the presence of antibodies is used to diagnose infection. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. USA, Med Res Inst Infect Dis, Appl Res Div, Ft Detrick, MD 21702 USA. Geocenters Inc, Ft Washington, MD 20744 USA. RP Anderson, GP (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Code 6910, Washington, DC 20375 USA. EM ganderson@cbmse.nrl.navy.mil RI Anderson, George/D-2461-2011 OI Anderson, George/0000-0001-7545-9893 NR 20 TC 24 Z9 25 U1 0 U2 3 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 1071-412X J9 CLIN DIAGN LAB IMMUN JI Clin. Diagn. Lab. Immunol. PD SEP PY 1998 VL 5 IS 5 BP 609 EP 612 PG 4 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 117NF UT WOS:000075787400003 PM 9729524 ER PT J AU Porter, KR Aguiar, J Richards, A Sandjaya, B Ignatias, I Hadiputranto, H Ridley, RG Takacs, B Wignall, FS Hoffman, SL Hayes, CG AF Porter, KR Aguiar, J Richards, A Sandjaya, B Ignatias, I Hadiputranto, H Ridley, RG Takacs, B Wignall, FS Hoffman, SL Hayes, CG TI Immune response against the Exp-1 protein of Plasmodium falciparum results in antibodies that cross-react with human T-cell lymphotropic virus type 1 proteins SO CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY LA English DT Article ID BLOOD-STAGE ANTIGEN; POPULATION AB To examine the role of the Plasmodium falciparum Exp-l blood-stage protein in producing antibodies that cross-react with human T-cell lymphotropic virus type I (HTLV-I) proteins, we studied sera from Indonesian volunteers who seroconverted to malaria after transmigrating to an area where malaria is hyperendemic, Samples from Philippine volunteers, that were used in a prior study that examined malaria antibodies that cross-react with HTLV-I proteins, were also used. Eighty-three percent of the Indonesian transmigrants developed antibodies against the malaria Exp-l protein by 6 months postmigration. Of these malaria seroconverters, 27% developed false-positive HTLV-I enzyme immunoassay (EIA) immunoreactivity, as indicated by indeterminate HTLV-I Western blot banding patterns. Five of the six Philippine samples tested were HTLV-I EIA false positive and Western blot indeterminate. When a recombinant Exp-l protein was used in blocking experiments, the HTLV-I Western blot immunoreactivity of sera from both groups was either completely eliminated or greatly reduced. No effect on the Western blot immunoreactivity of truly HTLV-I-positive sera was seen, To determine if immunization with the recombinant Exp-1 protein could elicit the production of HTLV-I antibodies, six mice were inoculated with the recombinant protein. Following administration of three 50-mu g doses of the protein, four of the six mice developed antibodies that cross-reacted with HTLV-I proteins on Western blot. These results indicate that the immune response against the malaria Exp-l protein may result in HTLV-I-cross-reacting antibodies that can lead to false-positive EIA and indeterminant Western blotting results. C1 Naval Med Res Unit 2, Jakarta, Indonesia. USN, Med Res Inst, Viral & Rickettsial Dis Program, Bethesda, MD USA. USN, Med Res Inst, Malaria Program, Bethesda, MD USA. F Hoffmann La Roche & Co Ltd, Dept Infect Dis, CH-4070 Basel, Switzerland. Dept Hlth, Jayapura, Irian Jay, Indonesia. RP Porter, KR (reprint author), US NAMRU 2, Box 3,Unit 8132, APO, AP 96520 USA. NR 8 TC 2 Z9 2 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 1071-412X J9 CLIN DIAGN LAB IMMUN JI Clin. Diagn. Lab. Immunol. PD SEP PY 1998 VL 5 IS 5 BP 721 EP 724 PG 4 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 117NF UT WOS:000075787400021 PM 9729542 ER PT J AU Wallace, MR Hill, HE Tasker, SA Miller, LK AF Wallace, MR Hill, HE Tasker, SA Miller, LK TI Hepatitis A in human immunodeficiency virus-infected patients SO CLINICAL INFECTIOUS DISEASES LA English DT Article ID HOMOSEXUAL MEN; HEPATOTROPIC VIRUSES; VACCINATION C1 Univ Cantabria, Serv Hematol Hemotherapy, Santander, Spain. Hosp Univ Marques Valdecilla, Dept Internal Med, Santander, Spain. RP Wallace, MR (reprint author), USN, Med Ctr, Div Clin Res, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 7 TC 14 Z9 15 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 1058-4838 J9 CLIN INFECT DIS JI Clin. Infect. Dis. PD SEP PY 1998 VL 27 IS 3 BP 651 EP 653 DI 10.1086/517144 PG 3 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 119VD UT WOS:000075917900043 PM 9770175 ER PT J AU Davis, AJ Fischer, G AF Davis, AJ Fischer, G TI Behavioral modeling of delta-sigma modulators SO COMPUTER STANDARDS & INTERFACES LA English DT Article DE delta-sigma modulation; behavioral modelling; simulation; computer-aided design; analog circuit imperfections ID PERFORMANCE; CONVERTER AB This paper presents an overview of DelSi, a MATLAB toolbox developed for the design and simulation of delta-sigma modulators. The DelSi toolbox can synthesize a stable noise-transfer function for complex network structures. The modelling tool consists of two c/c(++) programs, sdMod.c, a single stage delta-sigma modulator and firfilt.c, a decimating FIR filter. Cascaded modulators can be constructed using the programs as building blocks. The simulation tools support the inclusion of nonideal effects caused by circuit imperfections, such as amplifier finite open-loop gain, incomplete settling and saturation as well as capacitor ratio mismatches. Two design examples are presented: one for a 1-1-1 cascade and the other for a single-stage fifth modulator. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Ctr Underwater Warfare, Weap Syst Dept, Newport, RI 02841 USA. Univ Rhode Isl, Dept Elect Comp Engn, Kingston, RI 02881 USA. EM davis@ele.uri.edu; fischer@ele.uri.edu NR 17 TC 11 Z9 11 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5489 J9 COMP STAND INTER JI Comput. Stand. Interfaces PD SEP PY 1998 VL 19 IS 3-4 BP 189 EP 203 DI 10.1016/S0920-5489(98)00016-6 PG 15 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA 135PG UT WOS:000076811100003 ER PT J AU Gersonde, R Spiess, V Flores, JA Hagen, RA Kuhn, G AF Gersonde, R Spiess, V Flores, JA Hagen, RA Kuhn, G TI The sediments of Gunnerus Ridge and Kainan Maru Seamount (Indian sector of Southern Ocean) SO DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS LA English DT Article ID DRILLING PROJECT LEG-71; SOUTHWEST ATLANTIC; DEEP; LATITUDES; NEOGENE; DIATOMS; EOCENE AB Combined bathymetric, sediment echosounding and sediment coring data from two expeditions of the RV "Polarstern" (ANT-VIII/6, ANT-XI/4) provides the first more comprehensive overview of Cenozoic sedimentation in the remote area of the Gunnerus Ridge and Kainan Maru Seamount off the Antarctic Continent (Indian sector of Southern Ocean). The Neogene and Oligocene sediment sequences were affected by at least three generations of large scale slide and slump events, which occurred around the early/late Pliocene and the early/late Oligocene boundaries and during an earlier time period in the Paleogene. Possible triggers for slumping events might have been changes in the circulation pattern, changes in sea level, or earthquakes. Changes in water mass circulation could have affected the distribution of sediments since the onset of the Neogene in conjunction with the establishment of the Antarctic Circumpolar Current (ACC). The recovered sediments are predominantly biosiliceous mud and ooze: except for early Oligocene and Quaternary sequences, which contain calcareous nannofossils and foraminifera, respectively. The sediments have been deposited at low sedimentation rates ranging from a few millimeters to centimeters per 1000 yr. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Alfred Wegener Inst Polar & Marine Res, D-27515 Bremerhaven, Germany. Univ Bremen, Fachbereich Geowissensch 5, D-28334 Bremen, Germany. Univ Salamanca, Dept Geol, S-37008 Salamanca, Spain. USN, Res Lab, Washington, DC 20375 USA. RP Gersonde, R (reprint author), Alfred Wegener Inst Polar & Marine Res, Postbox 120161, D-27515 Bremerhaven, Germany. RI Flores, Jose-Abel/D-4218-2009; OI Flores, Jose-Abel/0000-0003-1909-293X; Kuhn, Gerhard/0000-0001-6069-7485 NR 45 TC 5 Z9 5 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0637 J9 DEEP-SEA RES PT I JI Deep-Sea Res. Part I-Oceanogr. Res. Pap. PD SEP PY 1998 VL 45 IS 9 BP 1515 EP 1540 DI 10.1016/S0967-0637(98)00024-7 PG 26 WC Oceanography SC Oceanography GA 131NH UT WOS:000076581800006 ER PT J AU Krapivin, VF Cherepenin, VA Phillips, GW August, RA Pautkin, AY Harper, MJ Tsang, FY AF Krapivin, VF Cherepenin, VA Phillips, GW August, RA Pautkin, AY Harper, MJ Tsang, FY TI An application of modelling technology to the study of radionuclear pollutants and heavy metals dynamics in the Angara-Yenisey river system SO ECOLOGICAL MODELLING LA English DT Article DE Angara-Yenisey river system; heavy metals; modeling; radionuclear pollution AB This paper considers the problem of the origin of the pollution level in the Yenisey river estuary which is located in north-central Siberia and empties into the Kara sea. In the framework of this problem, a joint American-Russian environmental and hydrophysical expedition to the Angara and Yenisey rivers of Siberia was accomplished in the summer of 1995. Using the results of the pollution measurements taken during this expedition, it becomes possible to begin the synthesis of the spatial mathematical model for pollution transport in the Angara-Yenisey river system. The model includes blocks describing the flows of pollutants from biogeochemical, hydrophysical and anthropogenic sources. The influence of soil-plant formations are considered. The model is designed for interactive use in the mode of a computer experiment. The results of model calculations and of the expedition are given. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, Inst Radioengn & Elect, Fryazino 141120, Russia. USN, Res Lab, Washington, DC 20375 USA. USN Acad, Annapolis, MD 21402 USA. Global Technol Inc, Idaho Falls, ID 83404 USA. RP Krapivin, VF (reprint author), Russian Acad Sci, Inst Radioengn & Elect, Vvedensky Sq 1, Fryazino 141120, Russia. NR 23 TC 8 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3800 J9 ECOL MODEL JI Ecol. Model. PD SEP 1 PY 1998 VL 111 IS 2-3 BP 121 EP 134 DI 10.1016/S0304-3800(98)00090-8 PG 14 WC Ecology SC Environmental Sciences & Ecology GA 133EJ UT WOS:000076673200002 ER PT J AU Brandt, JE Galy, AHM Luens, KM Travis, M Young, J Tong, J Chen, S Davis, TA Lee, KP Chen, BP Tushinski, R Hoffman, R AF Brandt, JE Galy, AHM Luens, KM Travis, M Young, J Tong, J Chen, S Davis, TA Lee, KP Chen, BP Tushinski, R Hoffman, R TI Bone marrow repopulation by human marrow stem cells after long-term expansion culture on a porcine endothelial cell line SO EXPERIMENTAL HEMATOLOGY LA English DT Article DE engraftment; cytokines; endothelial cells; bone marrow transplantation ID HEMATOPOIETIC PROGENITOR CELLS; RETROVIRAL-MEDIATED TRANSDUCTION; COLONY-STIMULATING FACTORS; IMMUNE-DEFICIENT MICE; IN-VITRO EXPANSION; EX-VIVO EXPANSION; C-KIT LIGAND; PERIPHERAL-BLOOD; FORMING CELLS; INTERLEUKIN-3 AB In vitro exposure of murine hematopoietic stem cells (HSCs) to cell cycle-inducing cytokines has been shown to result in a defect in the ability of these cells to engraft. We used a porcine microvascular endothelial cell (PMVEC) line in conjunction with exogenous interleukin (IL)-3, IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF), and stem cell factor (SCF) to expand human HSCs that express the CD34 and Thy-1 antigens but lack lineage-associated markers (CD34(+)Thy-1(+)Lin(-) cells). Ex vivo expansion of hematopoietic cells was evaluated in comparison to stromal cell-free, cytokine-supplemented cultures. Cells expressing the CD34(+)Thy(-)1(+)Lin(-) phenotype were detectable in both culture systems for up to 3 weeks. These cells were reisolated from the cultures and their ability to engraft human fetal bones implanted into SCID mice (SCID-hu bone) was tested. HSCs expanded in PMVEC coculture were consistently capable of competitive marrow repopulation with multilineage (CD19(+) B lymphoid, CD33(+) myeloid, and CD34(+) cells) progeny present 8 weeks postengraftment. In contrast, grafts composed of cells expanded in stroma-free cultures did not lead to multilineage SCID-hu bone repopulation. Proliferation analysis revealed that by 1 week of culture more than 80% of the cells in the PMVEC cocultures expressing the primitive CD34(+)CD38(-) phenotype had undergone cell division. Fewer than 1% of the cells that proliferated in the absence of stromal cells remained CD34+CD38-. These data suggest that the proliferation of HSCs in the presence of IL-3, IL-6, GM-CSF, and SCF without stromal cell support may result in impairment of engraftment capacity, which may be overcome by coculture with PMVECs. C1 Univ Illinois, Hematol Oncol Sect MC 734, Chicago, IL 60680 USA. Wayne State Univ, Karmanos Canc Inst, Detroit, MI USA. SyStemix, Dept Res, Palo Alto, CA USA. USN, Med Res Inst, Immune Cell Biol Program, Bethesda, MD USA. RP Hoffman, R (reprint author), Univ Illinois, Hematol Oncol Sect MC 734, 900 S Ashland Ave, Chicago, IL 60680 USA. RI Galy, Anne/J-4439-2013 OI Galy, Anne/0000-0002-0153-4392 NR 40 TC 53 Z9 57 U1 0 U2 0 PU CARDEN JENNINGS PUBL CO LTD PI CHARLOTTESVILLE PA BLAKE CTR, STE 200, 1224 W MAIN ST, CHARLOTTESVILLE, VA 22903 USA SN 0301-472X J9 EXP HEMATOL JI Exp. Hematol. PD SEP PY 1998 VL 26 IS 10 BP 950 EP 961 PG 12 WC Hematology; Medicine, Research & Experimental SC Hematology; Research & Experimental Medicine GA 115FV UT WOS:000075653600005 PM 9728930 ER PT J AU Smoot, NC AF Smoot, NC TI The trans-Pacific Chinook Trough megatrend SO GEOMORPHOLOGY LA English DT Article DE trans-Pacific; Chinook Trough megatrend; Fracture zone; Hess rise; Shatskiy Rise; Uyeda Ridge ID OCEANIC FRACTURE-ZONES; MULTI-BEAM SONAR; TECTONIC EVOLUTION; NORTH PACIFIC; BATHYMETRY; ATLANTIC; PLATE; RIDGE; ENVIRONMENT; ORIGIN AB The Chinook Trough is a trans-Pacific megatrend. By using heretofore unpublished bathymetry and geophysical data, the trend of the Chinook Trough megatrend has been determined from the Juan de Fuca Ridge in the Gulf of Alaska to the Izu-Bonin trench. The feature passes through the Emperor Fracture Zone, intersects the Krusenstern Fracture Zone at the Hess Rise, passes through the Emperor Seamounts, intersects the Mamua Fracture Zone and several unnamed NNW-SSE-trending fractures at the Shatskiy Rise. After an undetermined passage through Nadeshda Basin, it intersects another NNW-SSE-trending fracture zone, Kashima Fracture Zone, at Nelson Guyot, and ends as Uyeda Ridge. Instead of being a trough, the feature is a fracture zone, herein called a megatrend. The feature is colinear to the Mendocino and Clipperton Fracture Zones. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Oceanog Off, Seafloor Data Bases Div, Stennis Space Ctr, MS 39522 USA. RP Smoot, NC (reprint author), USN, Oceanog Off, Seafloor Data Bases Div, Stennis Space Ctr, MS 39522 USA. NR 46 TC 3 Z9 3 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-555X J9 GEOMORPHOLOGY JI Geomorphology PD SEP PY 1998 VL 24 IS 4 BP 333 EP 351 DI 10.1016/S0169-555X(98)00024-5 PG 19 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 115YT UT WOS:000075694500004 ER PT J AU Epping-Jordan, JE Williams, RA Pruitt, SD Patterson, TL Grant, I Wahlgren, DR Slater, MA Webster, JS Atkinson, JH AF Epping-Jordan, JE Williams, RA Pruitt, SD Patterson, TL Grant, I Wahlgren, DR Slater, MA Webster, JS Atkinson, JH TI Transition to chronic pain in men with low back pain: Predictive relationships among pain intensity, disability, and depressive symptoms SO HEALTH PSYCHOLOGY LA English DT Article DE low back pain; prediction; pain intensity; disability; depressive symptoms ID DESCRIPTOR DIFFERENTIAL SCALE; SICKNESS IMPACT PROFILE; PRIMARY-CARE; DISORDERS AB Pain intensity, disability, and depressive symptoms are hallmarks of chronic pain conditions, but little is known about the relationships among these symptoms in the transition from acute to chronic pain. In this study, an inception cohort of men with low back pain (N = 78) was assessed at 2, 6, and 12 months after pain onset. At 6 months, pain intensity, disability, and depressive symptoms were predicted only by their respective levels at 2 months after pain onset. At 12 months, pain intensity and depressive symptoms were predicted by heightened disability at 6 months after pain onset; 12-month depressive symptoms also were predicted by 2-month disability. Pain intensity was not predictive of changes in disability or depressive symptoms. These findings suggest that functional disability plays a more prominent role than pain intensity in the transition from acute to chronic pain. A "failure to adapt" conceptual model is presented to account for these results. C1 VA San Diego Healthcare Syst, Psychiat Serv 116A, San Diego, CA 92161 USA. Univ Calif San Diego, Sch Med, San Diego, CA 92103 USA. San Diego State Univ, Grad Sch Publ Hlth, Ctr Behav Epidemiol & Community Hlth, San Diego, CA 92182 USA. Sharp Hlth Care, San Diego, CA USA. USN, Med Ctr, San Diego, CA 92152 USA. RP Atkinson, JH (reprint author), VA San Diego Healthcare Syst, Psychiat Serv 116A, 3350 La Jolla Village Dr, San Diego, CA 92161 USA. NR 42 TC 42 Z9 42 U1 3 U2 5 PU AMER PSYCHOLOGICAL ASSOC PI WASHINGTON PA 750 FIRST ST NE, WASHINGTON, DC 20002-4242 USA SN 0278-6133 J9 HEALTH PSYCHOL JI Health Psychol. PD SEP PY 1998 VL 17 IS 5 BP 421 EP 427 DI 10.1037/0278-6133.17.5.421 PG 7 WC Psychology, Clinical; Psychology SC Psychology GA 123QV UT WOS:000076136600004 PM 9776000 ER PT J AU Masterson, D AF Masterson, D TI Military rebellion in Argentina: Between coups and consolidation. SO HISTORIAN LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Masterson, D (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU PHI ALPHA THETA PI ALLENTOWN PA THE HISTORIAN 50 COLLEGE DR, ALLENTOWN, PA 18104-6100 USA SN 0018-2370 J9 HISTORIAN JI Historian PD FAL PY 1998 VL 61 IS 1 BP 170 EP 171 PG 2 WC History SC History GA 147PD UT WOS:000077574900041 ER PT J AU Hofer, M Fermann, ME Goldberg, L AF Hofer, M Fermann, ME Goldberg, L TI High-power side-pumped passively mode-locked Er-Yb fiber laser SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE erbium; optical fiber devices; optical fiber lasers; ultrafast optics AB A side-pumped double-clad Er-Yb fiber laser passively mode-locked with a saturable absorber is demonstrated for the first time. Pumped with a power of 1 W from a broad-stripe diode laser, an environmentally stable cavity design produces positively chirped 3-ps pulses at a repetition rate of 30 MHz with an average output power of 50 mW, The pulses can be linearly compressed to 330 fs in a length of negative dispersion fiber, whereas nonlinear compression in standard telecom fibers yields 130-fs pulses with pulse energies of 1.2 nJ. C1 IMRA Amer, Ann Arbor, MI 48105 USA. USN, Res Lab, Washington, DC 20375 USA. RP Hofer, M (reprint author), IMRA Amer, Ann Arbor, MI 48105 USA. NR 7 TC 17 Z9 20 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD SEP PY 1998 VL 10 IS 9 BP 1247 EP 1249 DI 10.1109/68.705605 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 109RZ UT WOS:000075338100017 ER PT J AU Strifors, HC Gaunaurd, GC AF Strifors, HC Gaunaurd, GC TI Scattering of electromagnetic pulses by simple-shaped targets with radar cross section modified by a dielectric coating SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE electromagnetic scattering; radar cross sections ID FREQUENCY SIGNAL ANALYSIS; WIGNER DISTRIBUTION; TIME SIGNALS; TOOL AB We study the scattering interaction of electromagnetic pulses with a spherical target. The target is a perfectly conducting sphere coated with a thin dielectric layer. Two different hypothetical materials are specified: a lossy dielectric and a dielectric that also has magnetic losses. The monostatic radar cross section (RCS) is computed in each case and we examine the influence of the coating on the RCS. In particular, we compare the RCS of the coated sphere with the (normalized) backscattered power when a large perfectly conducting hat plate coated with the same dielectric layer is illuminated at normal incidence by the same waveform. In particular, rye find that except for frequencies below those within the efficiency band of the absorbent material, the normalized RCS of the coated sphere agrees well with the power reflection coefficient of the plate covered with the same kind of coating. For low-frequency incidences, the peaks and dips in the RCS are more prominent for the coated target than they are for the bare one. Analyzing the response of the spherical targets in the combined time-frequency domain we demonstrate that the coating itself, although reducing the RCS could introduce additional resonance features in the target's signature at low frequencies that could be used for target recognition purposes. This observation is also confirmed by a study of the bistatic RCS of these coated objects, which we have displayed in various color graphs. C1 Natl Def Res Estab, S-17290 Sundbyberg, Sweden. Naval Surface Warfare Ctr, Carderock Div, W Bethesda, MD 20817 USA. RP Strifors, HC (reprint author), Natl Def Res Estab, FOA-6, S-17290 Sundbyberg, Sweden. NR 25 TC 16 Z9 16 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD SEP PY 1998 VL 46 IS 9 BP 1252 EP 1262 DI 10.1109/8.719967 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 122XA UT WOS:000076095700002 ER PT J AU Boos, JB Kruppa, W Bennett, BR Park, D Kirchoefer, SW Bass, R Dietrich, HB AF Boos, JB Kruppa, W Bennett, BR Park, D Kirchoefer, SW Bass, R Dietrich, HB TI AlSb/InAs HEMT's for low-voltage, high-speed applications SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article DE InAs; MODFET's; quantum wells; semiconductor device fabrication; semiconductor device noise ID FIELD-EFFECT TRANSISTORS; HIGH-ELECTRON-MOBILITY; QUANTUM-WELLS; IMPACT IONIZATION; BREAKDOWN-VOLTAGE; CONDUCTANCE AB The design, fabrication, and characterization of 0.1 mu m AlSb/InAs HEMT's are reported. These devices have an In0.4Al0.6As/AlSb composite barrier above the InAs channel and a p(+) GaSb Layer within the AlSb buffer layer, The HEMT's exhibit a transconductance of 600 mS/mm and an f(T) of 120 GHz at V-DS = 0.6 V, An intrinsic f(T) of 160 GHz is obtained after the gate bonding pad capacitance is removed from an equivalent circuit. The present HEMT's have a noise figure of 1 dB with 14 dB associated gain at 4 GHz and V-DS = 0.4 V, Noise equivalent circuit simulation indicates that this noise figure is primarily limited by gate leakage current and that a noise figure of 0.3 dB at 4 GHz is achievable with expected technological improvements. HEMT's with a 0.5 mu m gate length on the same wafer exhibit a transconductance of 1 S/mm and an intrinsic f(T)L(g) product of 50 GHz-mu m. C1 USN, Res Lab, Washington, DC 20375 USA. RP Boos, JB (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 29 TC 109 Z9 109 U1 5 U2 20 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD SEP PY 1998 VL 45 IS 9 BP 1869 EP 1875 DI 10.1109/16.711349 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 112GQ UT WOS:000075486100002 ER PT J AU Corzine, KA Kuhn, BT Sudhoff, SD Hegner, HJ AF Corzine, KA Kuhn, BT Sudhoff, SD Hegner, HJ TI An improved method for incorporating magnetic saturation in the Q-D synchronous machine model SO IEEE TRANSACTIONS ON ENERGY CONVERSION LA English DT Article AB An improved technique for incorporating saturation into the q-d sris model (Park's model) of a synchronous machine is proposed. By choosing magnetizing flux linkage as a state variable, iterative procedures required by traditional methods are avoided. The saturation function is represented by an arctangent function which has some distinct advantages over polynomial representations and look-up tables. In particular, the parameters of the proposed function all have physical significance and the proposed function is defined over an infinite range of flux linkage. The model is verified for steady-state and transient conditions using a laboratory synchronous machine - rectifier system similar to those commonly used for Naval and aerospace power generation. C1 Univ Missouri, Dept Elect Engn, Rolla, MO 65409 USA. USN, Ctr Surface Warfare, Caderock Div, Annapolis Detachment, Annapolis, MD 21402 USA. RP Corzine, KA (reprint author), Univ Missouri, Dept Elect Engn, Rolla, MO 65409 USA. NR 8 TC 27 Z9 27 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8969 J9 IEEE T ENERGY CONVER JI IEEE Trans. Energy Convers. PD SEP PY 1998 VL 13 IS 3 BP 270 EP 275 DI 10.1109/60.707607 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA 113XQ UT WOS:000075579500019 ER PT J AU Lee, JS Papathanassiou, KP Ainsworth, TL Grunes, MR Reigber, A AF Lee, JS Papathanassiou, KP Ainsworth, TL Grunes, MR Reigber, A TI A new technique for noise filtering of SAR interferometric phase images SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article; Proceedings Paper CT 1997 International Geoscience and Remote Sensing Symposium (IGARSS 97) on Remote Sensing - A Scientific Vision for Sustainable Development CY AUG 03-08, 1997 CL SINGAPORE, SINGAPORE SP IEEE Geosci & Remote Sensing Soc, Natl Univ Singapore, Ctr Remote Imaging Sensing & Proc, NASA, NOAA, USN, Off Naval Res, Int Union Radio Sci DE interferometric synthetic aperture radar (IFSAR); phase noise filtering; phase noise modeling; phase unwrapping ID STATISTICS; RADAR AB This paper addresses the noise filtering problem for synthetic aperture radar (SAR) interferometric phase images. The phase noise is characterized by an additive noise model. The model is verified with an L-band shuttle imaging radar (SIR)-C interferogram. An adaptive filtering algorithm based on this noise model is developed. It emphasizes filtering noise adaptively according to the local noise level and filtering along fringes using directionally dependent windows. This algorithm is effective, especially for the tightly packed fringes of X-band interferometry. Using simulated and SIR-C/X-SAR repeat-pass generated interferograms, the effectiveness of this filter is demonstrated by its capabilities in residue reduction, adaptive noise filtering, and its ability to filter areas with high fringe rates. In addition, a scheme of incorporating this filtering algorithm in iterative phase unwrapping using a least-squares method is proposed. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. DLR, German Aerosp Res Ctr, D-82234 Oberpfaffenhofen, Germany. RP Lee, JS (reprint author), USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. EM lee@ccf.nrl.navy.mil; kostas.papathanassiou@dlr.de; toma@imsy1.nrl.navy.mil; andreas.reigber@dlr.de RI zhang, yonglei/G-1045-2011 NR 14 TC 185 Z9 248 U1 1 U2 12 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD SEP PY 1998 VL 36 IS 5 BP 1456 EP 1465 DI 10.1109/36.718849 PN 1 PG 10 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 121UU UT WOS:000076033700010 ER PT J AU Shih, SE Ding, KH Nghiem, SV Hsu, CC Kong, JA Jordan, AK AF Shih, SE Ding, KH Nghiem, SV Hsu, CC Kong, JA Jordan, AK TI Thin saline ice thickness retrieval using time-series C-band polarimetric radar measurements SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article; Proceedings Paper CT 1997 International Geoscience and Remote Sensing Symposium (IGARSS 97) on Remote Sensing - A Scientific Vision for Sustainable Development CY AUG 03-08, 1997 CL SINGAPORE, SINGAPORE SP IEEE Geosci & Remote Sensing Soc, Natl Univ Singapore, Ctr Remote Imaging Sensing & Proc, NASA, NOAA, USN, Off Naval Res, Int Union Radio Sci DE electromagnetic scattering inverse problems; radar polarimetry; sea ice; time series ID SEA-ICE; MICROWAVE-FREQUENCIES; SIGNATURES; BRINE; CONSTANT; GROWTH; MODEL AB The application of time-series radar measurements to accurately invert the thickness of saline ice is presented in this study. We describe briefly some experimental observations from the United States Army Cold Regions Research and Engineering Laboratory, Hanover, NEI, 1993 (CRRELEX'93) campaign of microwave scattering from sea ice. We demonstrate that volume scattering from brine inclusions is an important contribution to the backscatter response of saline ice in this case. From the experimental findings and the thermophysics of ice growth, we develop an inversion algorithm for the ice thickness based on a dynamic electromagnetic scattering model of saline ice. This inversion algorithm uses a parametric estimation approach in which the radiative transfer equation is used as the direct scattering model to calculate the backscattering signatures from ice medium and the Levenberg-Marquardt method is employed to retrieve ice thickness iteratively, Additional information provided by the saline ice thermodynamics is applied to constrain the electromagnetic inverse problem to achieve a reasonably accurate reconstruction. The inversion results using this algorithm and the data from CRRELEX'93 experiment are compared. The accurate thickness retrieval suggests the potential use of this algorithm for retrieving geophysical parameters from satellite remote-sensing data. C1 MIT, Dept Elect Engn & Comp Sci, Cambridge, MA 02139 USA. MIT, Elect Res Lab, Cambridge, MA 02139 USA. CALTECH, Jet Prop Lab, Ctr Space Microelect Technol, Pasadena, CA 91109 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Shih, SE (reprint author), MIT, Dept Elect Engn & Comp Sci, Cambridge, MA 02139 USA. EM shih@ewt.mit.edu NR 33 TC 12 Z9 13 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD SEP PY 1998 VL 36 IS 5 BP 1589 EP 1598 DI 10.1109/36.718862 PN 1 PG 10 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 121UU UT WOS:000076033700023 ER PT J AU Jordan, AK AF Jordan, AK TI Introduction to the special section on the electromagnetic properties of sea ice SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Jordan, AK (reprint author), USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD SEP PY 1998 VL 36 IS 5 BP 1631 EP 1631 DI 10.1109/TGRS.1998.718634 PN 2 PG 1 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 121ZQ UT WOS:000076046300001 ER PT J AU Jezek, KC Perovich, DK Golden, KM Luther, C Barber, DG Gogineni, P Grenfell, TC Jordan, AK Mobley, CD Nghiem, SV Onstott, RG AF Jezek, KC Perovich, DK Golden, KM Luther, C Barber, DG Gogineni, P Grenfell, TC Jordan, AK Mobley, CD Nghiem, SV Onstott, RG TI A broad spectral, interdisciplinary investigation of the electromagnetic properties of sea ice SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE electromagnetic (EM) scattering; geophysics; optics; sea ice ID RADAR BACKSCATTER AB This paper highlights the interrelationship of research completed by a team of investigators and presented in the several individual papers comprising this Special Section on the Office of Naval Research (ONR), Arlington, VA, Sponsored Sea Ice Electromagnetics Accelerated Research Initiative (ARI). The objectives of the initiative were the following: 1) understand the mechanisms and processes that link the morphological and physical properties of sea ice to its electromagnetic (EM) characteristics; 2) develop and verify predictive models for the interaction of visible, infrared, and microwave radiation with sea ice; 3) develop and verify inverse scattering techniques applicable to problems involving the interaction of EM radiation with sea ice. Guiding principles for the program were that all EM data be taken with concurrent physical property data (salinity, density, roughness, etc.) and that broad spectral data be acquired in as nearly a simultaneous fashion as possible. Over 30 investigators participated in laboratory, field, and modeling studies that spanned the EM spectrum from radio to ultraviolet wavelengths. An interdisciplinary approach that brought together sea ice physicists, remote-sensing experts tin EM measurements), and forward and inverse modelers (primarily mathematicians and EM theorists) was a hallmark of the program. Along with describing results from experiments and modeling efforts, possible paradigms for using broad spectral data in developing algorithms for analyzing remote-sensing data in terms of ice concentration, age, type, and possibly thickness are briefly discussed. C1 Ohio State Univ, Byrd Polar Res Ctr, Columbus, OH 43210 USA. USA, Cold Reg Res & Engn Lab, Hanover, NH 03755 USA. Univ Utah, Dept Math, Salt Lake City, UT 84112 USA. Off Naval Res, Arlington, VA 22217 USA. Univ Manitoba, Dept Geog, Winnipeg, MB R3T 2N2, Canada. Univ Kansas, Radar Syst & Remote Sensing Lab, Lawrence, KS 66045 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Sequoia Sci Inc, Mercer Isl, WA 98040 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Environm Res Inst Michigan, Ann Arbor, MI 48107 USA. RP Jezek, KC (reprint author), Ohio State Univ, Byrd Polar Res Ctr, Columbus, OH 43210 USA. NR 21 TC 13 Z9 13 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD SEP PY 1998 VL 36 IS 5 BP 1633 EP 1641 DI 10.1109/36.718635 PN 2 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 121ZQ UT WOS:000076046300002 ER PT J AU Golden, KM Borup, D Cheney, M Cherkaeva, E Dawson, MS Ding, KH Fung, AK Isaacson, D Johnson, SA Jordan, AK Kong, JA Kwok, R Nghiem, SV Onstott, RG Sylvester, J Winebrenner, DP Zabel, IHH AF Golden, KM Borup, D Cheney, M Cherkaeva, E Dawson, MS Ding, KH Fung, AK Isaacson, D Johnson, SA Jordan, AK Kong, JA Kwok, R Nghiem, SV Onstott, RG Sylvester, J Winebrenner, DP Zabel, IHH TI Inverse electromagnetic scattering models for sea ice SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Review DE dielectric materials; electromagnetic scattering by random media; electromagnetic scattering inverse problems; nonhomogeneous media; remote sensing; sea ice; snow ID SALINE ICE; POLARIMETRIC SIGNATURES; COMPLEX PERMITTIVITY; MICROWAVE RADIOMETER; DIELECTRIC-CONSTANT; HELMHOLTZ-EQUATION; BOUNDS; CLASSIFICATION; COMPOSITES; THICKNESS AB Inverse scattering algorithms for reconstructing the physical properties of sea Tee from scattered electromagnetic field data are presented. The development of these algorithms has advanced the theory of remote sensing, particularly in the microwave region, and has the potential to form the basis for a new generation of techniques for recovering sea ice properties, such as ice thickness, a parameter of geophysical and climatological importance. Moreover, the analysis underlying the algorithms has led to significant advances in the mathematical theory of inverse problems. In particular, the principal results include the following. 1) Inverse algorithms for reconstructing the complex permittivity in the Helmholtz equation in one and higher dimensions, based on layer stripping and nonlinear optimization, have been obtained and successfully applied to a (lossless) laboratory system. In one dimension, causality has been imposed to obtain stability of the solution and layer thicknesses can be obtained from the recovered dielectric profile, or directly from the reflection data through a nonlinear generalization of the Paley-Wiener theorem in Fourier analysis. 2) When the wavelength is much larger than the microstructural scale, the above algorithms reconstruct a profile of the effective complex permittivity of the sea ice, a composite of pure ice with random brine and air inclusions. A theory of inverse homogenization has been developed, which in this quasistatic regime, further inverts the reconstructed permittivities for microstructural information beyond the resolution of the wave. Rigorous bounds on brine volume and inclusion separation for a given value of the effective complex permittivity have been obtained as,well as an accurate algorithm for reconstructing the brine volume from a set of values. 3) Inverse algorithms designed to recover sea ice thickness have been developed. A coupled radiative transfer-thermodynamic sea ice inverse model has accurately reconstructed the growth of a thin, artificial sea ice sheet from time-series electromagnetic scattering data. Inversions for sea ice thickness have also been obtained through the application of neural networks to an analytic wave theory model,a reflectivity inversion Scheme, and the use of proxy indicators. The role of neural networks in sea ice classification is also considered. It is anticipated that the broad-ranging advances in inverse scattering theory presented here may find application to closely related problems, such as medical imaging, geophysical exploration, and nondestructive testing of materials as well as generating new techniques for remotely reconstructing sea ice parameters. C1 Univ Utah, Dept Math, Salt Lake City, UT 84112 USA. Univ Utah, Dept Bioengn, Salt Lake City, UT 84112 USA. Rensselaer Polytech Inst, Dept Math Sci, Troy, NY 12180 USA. Univ Texas, Dept Elect Engn, Arlington, TX 76019 USA. MIT, Dept Elect Engn, Cambridge, MA 02139 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Environm Res Inst Michigan, Ann Arbor, MI 48113 USA. Univ Washington, Dept Math, Seattle, WA 98195 USA. Univ Washington, Appl Phys Lab, Seattle, WA 98195 USA. Ohio State Univ, Byrd Polar Res Ctr, Columbus, OH 43210 USA. RP Golden, KM (reprint author), Univ Utah, Dept Math, Salt Lake City, UT 84112 USA. RI Kwok, Ron/A-9762-2008 OI Kwok, Ron/0000-0003-4051-5896 NR 110 TC 29 Z9 30 U1 2 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD SEP PY 1998 VL 36 IS 5 BP 1675 EP 1704 DI 10.1109/36.718638 PN 2 PG 30 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 121ZQ UT WOS:000076046300005 ER PT J AU Perovich, DK Longacre, J Barber, DG Maffione, RA Cota, GF Mobley, CD Gow, AJ Onstott, RG Grenfell, TC Pegau, WS Landry, M Roesler, CS AF Perovich, DK Longacre, J Barber, DG Maffione, RA Cota, GF Mobley, CD Gow, AJ Onstott, RG Grenfell, TC Pegau, WS Landry, M Roesler, CS TI Field observations of the electromagnetic properties of first-year sea ice SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE electromagnetic properties; physical-biological properties; remote sensing; sea ice; snow cover ID PHYSICAL-PROPERTIES; LIGHT-REFLECTION; ABSORPTION AB An interdisciplinary held experiment was conducted during April and May of 1994 at Point Barrow, AK, to investigate the relationship between the electromagnetic and physical-biological properties of first-year sea ice. Electromagnetic signatures of bare and snow-covered first-year ice were measured over a broad spectral range, including ultraviolet through near-infrared albedo, microwave emissivity, and radar backscatter. Observations indicated that the scattering of visible light varied significantly with depth in response to changes in the size and orientation of the ice crystals and in the number of brine and air inclusions. The scattering of visible light was greatest in the surface layer where there were numerous inclusions, and crystals tended to be small and randomly oriented. Changes in albedo over small horizontal distances were found to be related to surface layer conditions, including the number of air bubbles and particulate levels. Even for bare ice, transmittances were small with peaks in the blue-green. Scattering exceeds absorption throughout the snow and ice except in the skeletal layer colonized by bottom ice algae. Passive microwave emissivities showed a substantial difference between snow-covered and snow-free sites due to the effects of impedance matching at lower frequencies and volume scattering at higher frequencies produced by the snow. Spatial variability in the emissivity was quite small except at 90 GHz, where the emissivity was most sensitive to the amount of depth hoar. Radar backscatter coefficients were 5-6 dB larger for oblique viewing angles over snow-covered ice. C1 USA, Cold Reg Res & Engn Lab, Hanover, NH 03755 USA. USN, Ctr Underwater Syst, New London, CT 06320 USA. Univ Manitoba, Dept Geog, Ctr Earth Observat Sci, Winnipeg, MB R3T 2N2, Canada. HOBI Labs Inc, Watsonville, CA 95076 USA. Old Dominion Univ, Ctr Coastal Phys Oceanog, Norfolk, VA 23508 USA. Sequoia Sci Inc, Mercer Isl, WA 98040 USA. Environm Res Inst Michigan, Ann Arbor, MI 48107 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. Oregon State Univ, Corvallis, OR 97331 USA. Univ Connecticut, Dept Marine Sci, Groton, CT 06340 USA. RP Perovich, DK (reprint author), USA, Cold Reg Res & Engn Lab, 72 Lyme Rd, Hanover, NH 03755 USA. EM tgow@crrel.usace.army.mil NR 24 TC 24 Z9 25 U1 2 U2 10 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD SEP PY 1998 VL 36 IS 5 BP 1705 EP 1715 DI 10.1109/36.718639 PN 2 PG 11 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 121ZQ UT WOS:000076046300006 ER PT J AU Shih, SE Ding, KH Kong, JA Nghiem, SV Jordan, AK AF Shih, SE Ding, KH Kong, JA Nghiem, SV Jordan, AK TI Saline ice thickness retrieval under diurnal thermal cycling conditions SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE electromagnetic scattering inverse problems; radar polarimetry; sea ice; time series ID SEA-ICE; POLARIMETRIC SIGNATURES; MICROWAVE-FREQUENCIES; CONSTANT; EXCHANGE; GROWTH; BRINE AB An inverse scattering algorithm is presented that reconstructs ice growth under thermal cycling conditions by using time-series active microwave measurements. The algorithm uses a direct scattering model consisting of a physically based electromagnetic model that accounts for thermal and electromagnetic properties of ice and combined volume and surface scattering effects as well as a one-dimensional (1-D) thermodynamic model of saline ice growth that includes thermal interactions with the atmosphere. The combined thermodynamic-electromagnetic scattering model is applied to interpret the United States Army Cold Regions Research and Engineering Laboratory, Hanover, NH, 1994 experimental observations (CRRELEX'94) on both the ice growth and the diurnal cycles in C-band polarinetric backscatter, The crucial part of the inversion algorithm is the use of sequentially measured radar data together with the direct scattering model to retrieve the sea ice parameters. The algorithm was applied to CRRELEX'94 data and successfully reconstructed the evolution of ice growth under a thermal cycling environment. This work shows that the inversion algorithm using time-series data offers a distinct advantage over algorithms using individual microwave data set. C1 MIT, Dept Elect Engn & Comp Sci, Cambridge, MA 02139 USA. MIT, Elect Res Lab, Cambridge, MA 02139 USA. CALTECH, Jet Prop Lab, Ctr Space Microelect Technol, Pasadena, CA 91109 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Shih, SE (reprint author), MIT, Dept Elect Engn & Comp Sci, Cambridge, MA 02139 USA. NR 24 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD SEP PY 1998 VL 36 IS 5 BP 1731 EP 1742 DI 10.1109/36.718641 PN 2 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 121ZQ UT WOS:000076046300008 ER PT J AU Hewer, G Kenney, C Manjunath, BS AF Hewer, G Kenney, C Manjunath, BS TI Variational image segmentation using boundary functions SO IEEE TRANSACTIONS ON IMAGE PROCESSING LA English DT Article DE boundary functions; variational segmentation AB A general variational framework for image approximation and segmentation is introduced. By using a continuous "line-process" to represent edge boundaries, it is possible to formulate a variational theory of image segmentation and approximation in which the boundary function has a simple explicit form in terms of the approximation function. At the same time, this variational framework is general enough to include the most commonly used objective functions. Application is made to Mumford-Shah type functionals as well as those considered by Geman and others. Employing arbitrary L-p norms to measure smoothness and approximation allows the user to alternate between a least squares approach and one based on total variation, depending on the needs of a particular image. Since the optimal boundary function that minimizes the associated objective functional for a given approximation function can be found explicitly, the objective functional can be expressed in a reduced form that depends only on the approximating function. From this a partial differential equation (PDE) descent method, aimed at minimizing the objective functional, is derived. The method is fast and produces excellent results as illustrated by a number of real and synthetic image problems. C1 USN, Air Warfare Ctr, China Lake, CA 93555 USA. Univ Calif Santa Barbara, Dept Elect & Comp Engn, Santa Barbara, CA 93106 USA. RP USN, Air Warfare Ctr, China Lake, CA 93555 USA. EM manj@ece.ucsb.edu NR 26 TC 22 Z9 24 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1057-7149 EI 1941-0042 J9 IEEE T IMAGE PROCESS JI IEEE Trans. Image Process. PD SEP PY 1998 VL 7 IS 9 BP 1269 EP 1282 DI 10.1109/83.709660 PG 14 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 113HJ UT WOS:000075544600005 PM 18276339 ER PT J AU Sellami, L Newcomb, RW AF Sellami, L Newcomb, RW TI An inverse Hollis-Paulos artificial neural network SO IEEE TRANSACTIONS ON NEURAL NETWORKS LA English DT Article DE dynamical neural networks; Hollis-Paulos neural networks; inverse neural networks; semistate theory AB The Hollis-Paulos artificial neural network (HPANN) is convenient in terms of its possibility for realization of variable weight artificial neural networks (ANN's) in very large scale integration (VLSI) by MOS transistor circuits, though it is nondynamical and not driven by external inputs. Here we introduce dynamics and inputs into the HPANN and show that over the range of operation covered by the Hollis-Paulos theory the system has an inverse. In particular, we derive that inverse, in semistate form, and give simulation results on its operation, showing how well the input to the original HPANN can be recovered from the output of the HPANN when fed into the inverse system. A comparison is made with the previous inverse of the Hopfield ANN, Possible applications of these inverse systems are to decoding of transmitted ANN signals and to inverse filtering for the extraction of input signals from processed signals. C1 USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. RP Sellami, L (reprint author), USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1045-9227 J9 IEEE T NEURAL NETWOR JI IEEE Trans. Neural Netw. PD SEP PY 1998 VL 9 IS 5 BP 979 EP 986 DI 10.1109/72.712175 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 116HX UT WOS:000075719800021 PM 18255781 ER PT J AU Moffett, MB Trivett, DH Klippel, PJ Baird, PD AF Moffett, MB Trivett, DH Klippel, PJ Baird, PD TI A piezoelectric, flexural-disk, neutrally buoyant, underwater accelerometer SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article AB A piezoelectric, flexural-disk accelerometer for underwater use is composed of two PZT-5A lead zirconate-titanate disks that are bonded to an aluminum substrate. The substrate is edge-supported inside an aluminum housing. The housing is enclosed in syntactic foam so that the sensor is neutrally buoyant. The overall height is 1.0 in. (26 mm), the overall diameter is 1.9 in. (49 mm), and the total mass is 0.054 kg. With 25 ft (7.6 m) of (230 pF/m) cable attached, the sensitivity is -42 dB re 1 V-s(2)/m (-22 dB re 1 V/g), the capacitance is 5.0 nF, and the resonance frequency is 11 kHz. When used in conjunction with a Micro Networks MN3210 preamplifier, the spectral noise-equivalent acceleration floor is approximately -171 dB re 1 m/s(2)-root Hz, (-151 dB re 1 g/root Hz) at 5 kHz. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. Edo Corp, Acoust Div, Salt Lake City, UT 84115 USA. RP Moffett, MB (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02841 USA. NR 6 TC 5 Z9 7 U1 2 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-3010 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD SEP PY 1998 VL 45 IS 5 BP 1341 EP 1346 DI 10.1109/58.726460 PG 6 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA 129WX UT WOS:000076488000028 PM 18244296 ER PT J AU Tressler, JF Cao, WW Uchino, K Newnham, RE AF Tressler, JF Cao, WW Uchino, K Newnham, RE TI Finite element analysis of the cymbal-type flextensional transducer SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article AB The effect of material properties and dimensional changes on the fundamental resonance frequency of the cymbal transducer has been investigated using the ANSYS(R) finite element software. Vibration mode shapes, resonance frequencies, and admittance spectra for both air- and water-loading are calculated. Very good agreement is observed between the modeled and experimentally measured admittance spectra in the frequency range up to 200 kHz, establishing the validity of the model. The calculations show that the fundamental resonance frequency can be manipulated easily by changing the cymbal cap material or dimensions. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. RP Tressler, JF (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Cao, Wenwu/F-6091-2012 OI Cao, Wenwu/0000-0002-2447-1486 NR 13 TC 53 Z9 58 U1 1 U2 15 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-3010 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD SEP PY 1998 VL 45 IS 5 BP 1363 EP 1369 DI 10.1109/58.726463 PG 7 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA 129WX UT WOS:000076488000031 ER EF