FN Thomson Reuters Web of Science™ VR 1.0 PT J AU McGill, RA Chung, R Chrisey, DB Dorsey, PC Matthews, P Pique, A Mlsna, TE Stepnowski, JL AF McGill, RA Chung, R Chrisey, DB Dorsey, PC Matthews, P Pique, A Mlsna, TE Stepnowski, JL TI Performance optimization of surface acoustic wave chemical sensors SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article ID LASER-ABLATION AB Acoustic wave devices coated with a thin layer of chemoselective material provide highly sensitive chemical sensors for the detection and monitoring of vapors and gases. In this work, a variety of coating materials and coating deposition techniques have been evaluated on surface acoustic wave (SAW) devices. A novel thin film deposition technique, matrix assisted pulsed laser evaporation (MAPLE), is utilized to coat high quality polymer films on SAW devices, and conventional pulsed laser deposition is used to deposit a passivation layer of diamond-like-carbon on a SAW device surface to prevent water adsorption. In addition, chemoselective coatings are formed by covalent attachment of functionalized species to the silica surface of SAW devices. The self-assembled monolayer or near monolayer structures are designed to populate the SAW device surface with the desirable hexafluoroisopropanol moeity. The rapid kinetic signals achievable with the various coated SAW sensors during vapor tests are examined as a function of the coating material and the quality of the thin films. In parallel to the thin film deposition, growth, and vapor testing, the electrical characteristics of the SAW sensor have been characterized. The quality factor and residual phase noise of polymer coated SAW devices are examined, and a prediction of the theoretical limit of the phase noise performance of the loop oscillator is made. C1 USN, Res Lab, Washington, DC 20375 USA. Geocenters Inc, Ft Washington, MD 20744 USA. RP McGill, RA (reprint author), USN, Res Lab, Code 6670, Washington, DC 20375 USA. EM amcgill@ccf.nrl.navy.mil NR 29 TC 51 Z9 54 U1 1 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 1370 EP 1380 DI 10.1109/58.726464 PG 11 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA 129WX UT WOS:000076488000032 ER PT J AU Chusuei, CC Morris, RE Schreifels, JA AF Chusuei, CC Morris, RE Schreifels, JA TI Adsorption of N,N '-disalicylidene-1,2-propanediamine on 304 stainless steel SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID PHOTOELECTRON-SPECTROSCOPY; THERMAL-STABILITY; OXIDES; IRON; DECOMPOSITION; OXIDATION; OXYGEN AB The behavior of the jet fuel metal deactivator additive (MDA), N,N'-disalicylidene-1,2-propanediamine in some high-temperature tests, has raised questions concerning whether it would decompose on contact with hot metal surfaces in aircraft engines and fuel systems. The adsorption of this additive was studied on oxidized and oxide-free 304SS surfaces using X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption (TPD). XPS binding energy (BE) shifts indicated thermal decomposition on the surfaces. TPD revealed the growth of both physisorbed and chemisorbed states in accordance with the Stranski-Krastanov mechanism. MDA was only weakly chemisorbed onto the 304SS surface, with desorption energies of 47 kJ/mol on an oxidized surface and 33 kJ/mol on the oxide-free surface. These findings suggest that stainless steel would not likely contain a contiguous chemisorbed MDA multilayer that the adsorbed MDA could be removed from internal surfaces of aircraft fuel systems in regions of high-temperature and turbulent flow. C1 George Mason Univ, Dept Chem, Fairfax, VA 22030 USA. USN, Res Lab, Navy Technol Ctr Safety & Survivabil, Washington, DC 20375 USA. RP Schreifels, JA (reprint author), Texas A&M Univ, Dept Chem, POB 300012, College Stn, TX 77842 USA. EM jschreif@gmu.edu NR 52 TC 5 Z9 5 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD SEP PY 1998 VL 37 IS 9 BP 3610 EP 3617 DI 10.1021/ie980076s PG 8 WC Engineering, Chemical SC Engineering GA 119DR UT WOS:000075881000012 ER PT J AU Wang, RB Doolan, DL Charoenvit, Y Hedstrom, RC Gardner, MJ Hobart, P Tine, J Sedegah, M Fallarme, V Sacci, JB Kaur, M Klinman, DM Hoffman, SL Weiss, WR AF Wang, RB Doolan, DL Charoenvit, Y Hedstrom, RC Gardner, MJ Hobart, P Tine, J Sedegah, M Fallarme, V Sacci, JB Kaur, M Klinman, DM Hoffman, SL Weiss, WR TI Simultaneous induction of multiple antigen-specific cytotoxic T lymphocytes in nonhuman primates by immunization with a mixture of four Plasmodium falciparum DNA plasmids SO INFECTION AND IMMUNITY LA English DT Article ID SPOROZOITE SURFACE PROTEIN-2; INTRADERMAL GENE IMMUNIZATION; HUMAN MALARIA PARASITE; CIRCUMSPOROZOITE PROTEIN; RHESUS-MONKEYS; INFECTED HEPATOCYTES; VACCINE CANDIDATE; SYNTHETIC PEPTIDE; INTERFERON-GAMMA; CELL EPITOPES AB CD8(+) T cells have been implicated as critical effector cells in protective immunity against malaria parasites developing within hepatocytes, A vaccine that protects against malaria by inducing CD8(+) T cells will probably have to include multiple epitopes on the same protein or different proteins, because of parasite polymorphism and genetic restriction of T-cell responses. To determine if CD8(+) T-cell responses against multiple P. falciparum proteins can be induced in primates by immunization with plasmid DNA, rhesus monkeys were immunized intramuscularly with a mixture of DNA plasmids encoding four P. falciparum proteins or with individual plasmids. All six monkeys immunized with PfCSP DNA, seven of nine immunized with PfSSP2 DNA, and five of six immunized with PfExp-1 or PfLSA-1 DNA had detectable antigen-specific cytotoxic T lymphocytes (CTL) after in vitro restimulation of peripheral blood mononuclear cells. CTL activity was genetically restricted and dependent on CD8(+) T cells. By providing the first evidence for primates that immunization with a mixture of DNA plasmids induces CD8(+) T-cell responses against all the components of the mixture, these studies provide the foundation for multigene immunization of humans. C1 USN, Med Res Inst, Malaria Program, Rockville, MD 20889 USA. Henry M Jackson Fdn, Rockville, MD 20852 USA. Vical Inc, San Diego, CA 92121 USA. Virogenet Corp, Troy, NY 12180 USA. Univ Maryland, Dept Immunol & Microbiol, Baltimore, MD 21201 USA. US FDA, Ctr Biol Evaluat & Res, Sect Retroviral Immunol, Bethesda, MD 20892 USA. RP Weiss, WR (reprint author), USN, Med Res Inst, Malaria Program, 12300 Washington Ave, Rockville, MD 20852 USA. RI Doolan, Denise/F-1969-2015 NR 60 TC 54 Z9 59 U1 0 U2 0 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0019-9567 J9 INFECT IMMUN JI Infect. Immun. PD SEP PY 1998 VL 66 IS 9 BP 4193 EP 4202 PG 10 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 113RF UT WOS:000075564500028 PM 9712767 ER PT J AU Appleby, DF AF Appleby, DF TI The Frankish world, 750-900 SO INTERNATIONAL HISTORY REVIEW LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Appleby, DF (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SIMON FRASER UNIV, INT HISTORY REVIEW PI BURNABY PA EAA 2015, BURNABY, BC V5A 1S6, CANADA SN 0707-5332 J9 INT HIST REV JI Int. Hist. Rev. PD SEP PY 1998 VL 20 IS 3 BP 638 EP 640 PG 3 WC History SC History GA 132HC UT WOS:000076623400020 ER PT J AU Stern, RJ Smoot, NC AF Stern, RJ Smoot, NC TI A bathymetric overview of the Mariana forearc SO ISLAND ARC LA English DT Article DE bathymetry; forearc; Mariana arc ID CONVERGENT MARGINS; SUBDUCTION ZONES; VOLCANIC-ROCKS; SEAMARC-II; ARC; TRENCH; TROUGH; EVOLUTION; EROSION; ORIGIN AB Bathymetric data at a 200-m contour interval for the entire Mariana forearc, from south of 13 degrees N to 25 degrees N, permits the first comprehensive overview of this feature. The Mariana forearc represents a sediment-starved end-member. The forearc in its southern and central sections is divisible into a structurally complex eastern province and a less-deformed western province. Despite the absence of an accretionary complex the Mariana forearc has a well-defined outer-are high; this probably results from a greater concentration of low-density serpentinized mantle lithosphere beneath the outer forearc relative to the inner forearc. This serpentinization gradient is coupled with differing deformational styles of thinner and more brittle lithosphere beneath the outer forearc compared to thicker and more ductile lithosphere beneath the inner forearc. The bathymetric data also support models calling for extension along-strike of the forearc, reflecting an increase in are length accompanying the crescent-shaped opening of the Mariana Trough back-are basin. Both northeast and northwest ridges and grabens can be identified, with the latter restricted to the southern part of the forearc and the former widely distributed in the central and northern forearc. Northeast-oriented extensional structures are supplanted northward by long, linear northwest-trending structures that ale interpreted as left-lateral strike-slip faults. These variations in deformation along-strike of the forearc manifest a transition from nearly orthogonal convergence in the south to highly oblique convergence in the north. C1 Univ Texas, Dept Geosci, Richardson, TX 75083 USA. USN, Seafloor Data Bases Div, Oceanog Off, Stennis Sci Ctr, Bay St Louis, MS 39522 USA. RP Stern, RJ (reprint author), Univ Texas, Dept Geosci, Box 830688, Richardson, TX 75083 USA. NR 51 TC 26 Z9 28 U1 0 U2 5 PU BLACKWELL SCIENCE PI CARLTON PA 54 UNIVERSITY ST, P O BOX 378, CARLTON, VICTORIA 3053, AUSTRALIA SN 1038-4871 J9 ISL ARC JI Isl. Arc. PD SEP PY 1998 VL 7 IS 3 BP 525 EP 540 DI 10.1111/j.1440-1738.1998.00208.x PG 16 WC Geosciences, Multidisciplinary SC Geology GA 122ED UT WOS:000076058200019 ER PT J AU Blank, DA AF Blank, DA TI Universal power optimized work for reciprocating internally reversible Stirling-like heat engine cycles with regeneration and linear external heat transfer SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MAXIMUM POWER; EFFICIENCY AB When bounded by two infinite thermal reservoirs, the theory of irreversible thermodynamics for reciprocating externally irreversible cycles yields to an optimum efficiency at maximum power output of eta=1-(T-L/T-H)(0.5) for internally reversible Stirling-like cycles using regeneration and linear heat transfer modes is in contrast to the upper limit for Stirling cycles of eta=1-(T-L/T-H) obtained from classical thermodynamics. This optimum behavior is, however, only based on cycle temperature bounds. For reciprocating cycles one must go a step further and minimize cycle time. While executing this new step for finite thermal reservoirs, it was discovered that, for the general family of reciprocating Stirling-like cycles, the finite-time optimum work output (W-opt) at maximum power is less than (and in the limit of ideal regeneration, infinite reservoirs and of no internal irreversibility, is equal to) exactly one-half of the work of the externally reversible cycle operating at maximum thermal efficiency (Carnot work, W-rev) between the same temperature limits (i.e., W-opt less than or equal to 1/2W(rev)). To accomplish this the analysis goes beyond earlier works to use time symmetry to better optimize overall cycle power. Because this procedure results in the concurrent employment of the first and second laws of thermodynamics, it ensures optimal allocation of thermal conductances at the hot and cold ends while simultaneously achieving both minimization of internal entropy generation and maximization of specific cycle work for a given set of operating temperatures. Based on linear heat transfer laws, this expression for optimum work is shown to be independent of heat conductances. Finally, the analysis establishes that the maximum power attainable for a Stirling-like reciprocating cycle operating between two temperature bounds is always less than (and in the limit of power optimized Carnot conditions, equal to) one-half of that obtained for the continuous counterpart of the same cycle operating between the same temperature bounds. (C) 1998 American Institute of Physics. [S0021-8979(98)07713-5]. C1 USN Acad, Annapolis, MD 21402 USA. RP Blank, DA (reprint author), Indian Inst Technol, Dept Mech Engn, Kharagpur 721302, W Bengal, India. NR 17 TC 13 Z9 13 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 SEP 1 PY 1998 VL 84 IS 5 BP 2385 EP 2392 DI 10.1063/1.368364 PG 8 WC Physics, Applied SC Physics GA 114CC UT WOS:000075590700003 ER PT J AU Culbertson, JC Newman, HS Wilker, C AF Culbertson, JC Newman, HS Wilker, C TI Optical probe of microwave current distributions in high temperature superconducting transmission lines SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CURRENT-DENSITY; CRITICAL-STATE; FILMS; MICROSCOPY; MICROSTRIP; DEPOSITION; RESOLUTION; IMPEDANCE; YBA2CU3O7 AB This work develops two techniques for optically probing the spatial profile of microwave frequency superconducting currents. As an application, we measured the effects of high microwave powers on the spatial distribution of current on coplanar superconducting transmission lines fabricated using YBa2Cu3O7-delta and Tl2Ba2CaCu2O8. For both techniques, a focused light-spot served as the spatial probe whose effect was measured through the change in transmitted microwave power. For resonant geometries, the change was due to the kinetic-inductance bolometric effect; for nonresonant geometries, the change was due to the resistive-transition bolometric effect. Kinetic-inductance photoresponse measurements were acquired by setting the microwave frequency on the shoulder of a resonance and measuring the change in the microwave power transmitted through the device that occurred when the absorption of light shifted the frequency of the resonance. These kinetic-inductance measurements were performed as a function of microwave power on a YBa2Cu3O7-delta coplanar device at 74 K and on a Tl2Ba2CaCu2O8 coplanar device at 80 K. Because the photoresponse in this technique is proportional to the square of the local current density underneath the light spot (as opposed to directly proportional), this technique is sensitive to current redistribution on length scales much smaller than the similar to 6 mu m spatial resolution of our measurements. Extrinsic (defect and grain boundary associated) and intrinsic photoresponses were measured. Both coplanar samples showed no change in the intrinsic spatial distribution of the current as the microwave power was varied. At all temperatures the Tl2Ba2CaCu2O8 sample exhibited substantial extrinsic spatial variations on a distance scale equal to the Rim's similar to 5 mu m grain size; these spatial variations became more dramatic as the temperature T approached the critical temperature T-c. The spatial variations for the finer-grained YBa2Cu3O7 sample were much less pronounced. Behavior consistent with T-c being several degrees lower at the film edges was observed as T approached T-c; the edge-current photoresponse started to narrow, increase faster than linearly with light power, and move away from the film edges toward the center of the strip. lowering the light power lessened these effects. Resistive-bolometric photoresponse measurements performed at temperatures within the resistive transition exhibited the same light power effects near T-c. The kinetic-inductance photoresponse can also be used as a probe of the local quality of unpatterned superconducting films; for this usage an unpatterned film serves as one wall of a resonant cavity and a focused light beam is scanned through the transparent substrate onto the underside of the superconducting film while monitoring the shift in the cavity resonance. (C) 1998 American Institute of Physics. [S0021-8979(98)03815-8] C1 USN, Res Lab, Washington, DC 20375 USA. Dupont Superconduct, Expt Stn, Wilmington, DE 19880 USA. RP USN, Res Lab, Washington, DC 20375 USA. EM james.culbertson@nrl.navy.mil NR 27 TC 19 Z9 19 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD SEP 1 PY 1998 VL 84 IS 5 BP 2768 EP 2787 DI 10.1063/1.368390 PG 20 WC Physics, Applied SC Physics GA 114CC UT WOS:000075590700056 ER PT J AU Kayar, SR Parker, EC Aukhert, EO AF Kayar, SR Parker, EC Aukhert, EO TI Relationship between T-wave amplitude and oxygen pulse in guinea pigs in hyperbaric helium and hydrogen SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE diving; gas density; electrocardiogram; heart rate; high pressure neurological syndrome; metabolic rate; telemetry ID HEART-RATE; PRESSURE; FREQUENCY; HUMANS; DIVE AB Diving is known to induce a change in the amplitude of the T wave (A(Tw)) of electrocardiograms, but it is unknown whether this is linked to a change in cardiovascular performance. We analyzed A(Tw) in guinea pigs at 10-60 atm and 25-36 degrees C, breathing 2% O-2 in either helium (heliox; n = 10) or hydrogen (hydrox; n = 9) for Ih at each pressure. Core temperature and electrocardiograms were detected by using implanted radiotelemeters. O-2 consumption rate was measured by using gas chromatography. In a previous study (S. R. Kayar and E. C. Parker. J. Appl. Physiol. 82: 988-997, 1997), we analyzed the O-2 pulse, i.e., the O-2 consumption rate per heart beat, in the same animals. By multivariate regression analysis, we identified variables that were significant to O-2 pulse: body surface area, chamber temperature, core temperature, and pressure. In this study, inclusion of A(Tw) made a significantly better model with fewer variables. After normalizing for chamber temperature and pressure, the O-2 pulse increased with increasing A(Tw) in heliox (P = 0.001) but with decreasing A(Tw) in hydrox (P < 0.001). Thus A(Tw) is associated with the differences in O-2 pulse for animals breathing heliox vs. hydrox. C1 USN, Med Res Inst, Albert R Behnke Diving Med Res Ctr, Bethesda, MD 20889 USA. RP Kayar, SR (reprint author), USN, Med Res Inst, Albert R Behnke Diving Med Res Ctr, Code 0512,8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 34 TC 3 Z9 4 U1 0 U2 0 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 SEP PY 1998 VL 85 IS 3 BP 798 EP 806 PG 9 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA 117KY UT WOS:000075781500004 PM 9729550 ER PT J AU Gilardi, RD Butcher, RJ AF Gilardi, RD Butcher, RJ TI A new class of flexible energetic salts, part 5: The structures of two hexammonium polymorphs and the ethane-1,2-diammonium salts of dinitramide SO JOURNAL OF CHEMICAL CRYSTALLOGRAPHY LA English DT Article DE hexamine structures; hexammonium structures; ethane-1,2-diammonium structures; dinitramide structures ID THERMOCHEMISTRY AB The crystal structures of two hexammonium polymorphs, 1 and 2, and the ethane-1,2-diammonium, 3, salts of dinitramide have been determined. 1 crystallizes in the triclinic space group with cell dimensions a = 6.391(2), b = 7.5826(9), c = 10.828(1) Angstrom, a = 77.58(1), beta = 88.18 (2), gamma = 87.54(2)degrees, 2 crystallizes in the monoclinic space group P2(1)/c with cell dimensions a = 6.4893(3), b = 14.5149(8), c = 10.6557(4) Angstrom, beta = 94.300(4)degrees and 3 crystallizes in the triclinic space group with cell dimensions a = 5.614(1), b = 6.867(2), c = 7.371(2) Angstrom, alpha = 68.89(2), beta = 89.00(2), gamma = 78.90(2)degrees. The three structures all contain protonated amine cations which are involved in hydrogen bonding interactions with dinitramide anions. C1 USN, Struct Matter Lab, Res Lab, Washington, DC 20375 USA. Howard Univ, Dept Chem, Washington, DC 20059 USA. RP Gilardi, RD (reprint author), USN, Struct Matter Lab, Res Lab, Washington, DC 20375 USA. RI G, Neela/H-3016-2014 NR 13 TC 13 Z9 13 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1074-1542 J9 J CHEM CRYSTALLOGR JI J. Chem. Crystallogr. PD SEP PY 1998 VL 28 IS 9 BP 673 EP 681 DI 10.1023/A:1021743916604 PG 9 WC Crystallography; Spectroscopy SC Crystallography; Spectroscopy GA 171LX UT WOS:000078866200002 ER PT J AU Orlin, PA Perkins, AL AF Orlin, PA Perkins, AL TI A frequency accurate finite difference scheme for burgers equation SO JOURNAL OF COMPUTATIONAL ACOUSTICS LA English DT Article AB A method is presented for designing a one-step, explicit finite difference scheme for solving the inviscid Burgers equation based on an a priori specification of dissipation and phase accuracy requirements. Frequency accurate temporal and spatial approximations with undetermined coefficients are used, together with a set of constraints that ensure that the approximations converge as the spatial and temporal grid sizes approach zero and satisfy the Lax Equivalence Theorem. A practical design of the difference scheme using a heuristic zero placement method, combined with a stability requirement, results in a linear matrix problem which is solved to obtain the undetermined coefficients. The partial differential equation itself provides the relationship between the temporal and spatial frequency dependence in the numerical approximation. C1 Univ So Mississippi, Ctr Higher Learning, Stennis Space Ctr, MS 39529 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Orlin, PA (reprint author), Univ So Mississippi, Ctr Higher Learning, Stennis Space Ctr, MS 39529 USA. NR 13 TC 2 Z9 2 U1 0 U2 0 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 SEP PY 1998 VL 6 IS 3 BP 321 EP 335 DI 10.1142/S0218396X98000223 PG 15 WC Acoustics; Mathematics, Interdisciplinary Applications SC Acoustics; Mathematics GA 157WM UT WOS:000078084700003 ER PT J AU Johnson, HM Singh, A Young, RHF AF Johnson, HM Singh, A Young, RHF TI Fall protection analysis for workers on residential roofs SO JOURNAL OF CONSTRUCTION ENGINEERING AND MANAGEMENT-ASCE LA English DT Article AB Safety during residential roof construction and repair activities is of significant concern since many injuries occur, especially as a result of falls. The Hawaii Occupational Safety and Health Division of the Hawaii Department of Labor commissioned a research project to investigate this matter. This study involves an evaluation of existing regulations, construction practices, and alternate fall protection measures. It is found that the current state of compliance is poor; fall protection plans are not prepared as required, and positive safety measures such as guardrails and personal fall arrest systems are not used. The reasons for this are many, including the extreme competitiveness of the home building and roofing industries, unsafe worker behavior, design difficulties, conventional construction practices, and a lack of knowledge. Fall protection regulations are misunderstood, and the fall protection plan is particularly prone to poor implementation. For fall protection systems to be implemented voluntarily, they must be feasible, simple, economical, protective, and flexible. Several systems were analyzed for their ability to meet these criteria. The most promising systems included prefabrication of the roof system and personal fall arrest systems use. This paper presents the findings of the study and recommendations for optimal enforcement with an aim at reducing fall injuries. C1 USN, Civ Engn Corps, Aiea, HI 96701 USA. RP Johnson, HM (reprint author), USN, Civ Engn Corps, 98-673 Kaahele St, Aiea, HI 96701 USA. NR 12 TC 15 Z9 16 U1 1 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 USA SN 0733-9364 J9 J CONSTR ENG M ASCE JI J. Constr. Eng. Manage.-ASCE PD SEP-OCT PY 1998 VL 124 IS 5 BP 418 EP 428 DI 10.1061/(ASCE)0733-9364(1998)124:5(418) PG 11 WC Construction & Building Technology; Engineering, Industrial; Engineering, Civil SC Construction & Building Technology; Engineering GA 121XL UT WOS:000076041100010 ER PT J AU Pieper, RJ Kraus, AD AF Pieper, RJ Kraus, AD TI Performance analysis of double stack cold plates covering all conditions of asymmetric heat loading SO JOURNAL OF ELECTRONIC PACKAGING LA English DT Article AB Double stack, force-cooled cold plates, which are used as electronic chassis, are investigated for all conditions of unequal temperature and heat loading. A closed form solution that relates the plate temperatures to composite heat loads is derived. This analysis covers all regimes of operation. In particular, this includes the previously ignored regime in which no adiabatic point exists anywhere on either of the fins connecting cover and splitter plates, The heat dissipating advantage of the double stack structure, over a similarly designed single stack structure, is predicted with the analysis presented in the paper. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Pieper, RJ (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. NR 18 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 1043-7398 J9 J ELECTRON PACKAGING JI J. Electron. Packag. PD SEP PY 1998 VL 120 IS 3 BP 296 EP 301 DI 10.1115/1.2792636 PG 6 WC Engineering, Electrical & Electronic; Engineering, Mechanical SC Engineering GA 125QE UT WOS:000076247900012 ER PT J AU Watson, KP Granger, RA AF Watson, KP Granger, RA TI Hydrodynamic effect of a satellite transmitter on a juvenile green turtle (Chelonia mydas) SO JOURNAL OF EXPERIMENTAL BIOLOGY LA English DT Article DE green turtle; Chelonia mydas; hydrodynamics; lift; drag; pitch; transmitter; telemetry; energy; swimming ID SEA TURTLE; TELEMETRY; PENGUINS; TRACKING AB Wind tunnel tests were performed to measure the effect of a satellite transmitter on a juvenile green turtle (Chelonia mydas), A full-scale turtle model was constructed from an 11.5 kg specimen with a 48 cm carapace length, and a transmitter model was constructed from a Telonics ST-6. The turtle model was tested in a wind tunnel with and without the transmitter, which was mounted on the forward, topmost part of the carapace, Drag,,lift and pitch moment were measured for several speeds and flow angles, and the data were scaled for application to the marine environment. At small flow angles representative of straight-line swimming, the transmitter increased drag by 27-30 %, reduced lift by less than 10 % and increased the pitch moment by 11-42 %, On the basis of the drag data at zero angle of attack, it is estimated that the backpack will reduce swimming speed by 11 %, assuming that the turtle produces the same thrust with the unit attached. The drag data are also used to estimate the effect of a transmitter on the swimming energetics of an adult green turtle. Design guidelines are included to minimize the adverse forces and moments caused by the transmitter. C1 USN, Ctr Surface Warfare, Coastal Syst Stn, Panama City, FL 32407 USA. USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Watson, KP (reprint author), USN, Ctr Surface Warfare, Coastal Syst Stn, Code R11, Panama City, FL 32407 USA. NR 22 TC 48 Z9 54 U1 0 U2 10 PU COMPANY OF BIOLOGISTS LTD PI CAMBRIDGE PA BIDDER BUILDING CAMBRIDGE COMMERCIAL PARK COWLEY RD, CAMBRIDGE, CAMBS, ENGLAND CB4 4DL SN 0022-0949 J9 J EXP BIOL JI J. Exp. Biol. PD SEP PY 1998 VL 201 IS 17 BP 2497 EP 2505 PG 9 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 121KT UT WOS:000076013500005 ER PT J AU Jayakody, C Nelson, GL Sorathia, U Lewandowski, S AF Jayakody, C Nelson, GL Sorathia, U Lewandowski, S TI A cone calorimetric study of flame retardant elastomeric polyurethanes modified with siloxanes and commercial flame retardant additives SO JOURNAL OF FIRE SCIENCES LA English DT Article DE polyurethane elastomers; diphenylmethane-4,4 '-diisocyanate (MDI); Baytec (R) prepolymers; polydimethylsiloxanes; powdered siloxane additives; commercial flame retardant additives; flame retardancy; Cone Calorimeter; time to sustained ignition (TTI); peak heat release rate (PHRR); average heat release rate (Ave. HRR); total heat release (THR); average specific extinction area (Ave. SEA) ID URETHANE BLOCK-COPOLYMERS AB Polyurethanes are the single most versatile family of polymers with a wide range of applications. There is a substantial need for the development of polyurethane materials with low heat release rate and low smoke release rate. In this study, an extensive series of elastomeric polyurethanes based on diphenylmethane-4,4 '-diisocyanate (MDI) prepolymers were prepared and further modified with fluid and powered siloxanes and conventional flame retardant additives. The flame retardant behavior of these polymers was studied using the Cone Calorimeter (ASTM: E-1354), the instrument that has emerged as an important tool for the analytical testing of materials for their fire properties.** All powdered siloxane additives used in this study, even at 5% loading level, gave a 70-80% reduction in peak heat release rates compared to standard materials. The reductions of peak HRR of fluid siloxane-modified materials compared to the base material were in the range of 49-78%. The conventional flame retardant additives used in this study also reduced peak heat release rate dramatically. The synergistic effect of conventional flame retardant additives with siloxane powders is discussed. C1 Florida Inst Technol, Dept Chem, Melbourne, FL 32901 USA. USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. Bayer Corp, Div Polymers, Pittsburgh, PA 15205 USA. RP Nelson, GL (reprint author), Florida Inst Technol, Dept Chem, Melbourne, FL 32901 USA. NR 10 TC 14 Z9 15 U1 1 U2 6 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0734-9041 J9 J FIRE SCI JI J. Fire Sci. PD SEP-OCT PY 1998 VL 16 IS 5 BP 351 EP 382 DI 10.1177/073490419801600504 PG 32 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 168NG UT WOS:000078698700004 ER PT J AU Kim, KH AF Kim, KH TI A design method for high-speed propulsor blades SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. RP Kim, KH (reprint author), USN, Ctr Surface Warfare, Carderock Div, 9500 MacArthur Blvd W, Bethesda, MD 20817 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD SEP PY 1998 VL 120 IS 3 BP 431 EP 431 DI 10.1115/1.2820674 PG 1 WC Engineering, Mechanical SC Engineering GA 125RY UT WOS:000076251900002 ER PT J AU Obenschain, SP AF Obenschain, SP TI The KrF direct drive fusion concept SO JOURNAL OF FUSION ENERGY LA English DT Article; Proceedings Paper CT Fusion Power Associates Annual Meeting and Symposium on Cost-Effective Steps to Fusion Power CY JAN 25-27, 1999 CL MARINA DEL REY, CALIFORNIA DE laser fusion; krypton fluoride lasers AB In collaboration with other laboratories, we are beginning a program to study and demonstrate the scientific, technical and economic feasibility of power production using laser fusion. The program, based on the development of a high average power Krypton Fluoride laser, is described in this paper. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Obenschain, SP (reprint author), USN, Res Lab, Div Plasma Phys, Code 6731,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0164-0313 J9 J FUSION ENERG JI J. Fusion Energy PD SEP PY 1998 VL 17 IS 3 BP 219 EP 220 DI 10.1023/A:1021854128204 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 359EX UT WOS:000089599500009 ER PT J AU Dahlburg, JP Gardner, JH Schmitt, AJ Obenschain, SP AF Dahlburg, JP Gardner, JH Schmitt, AJ Obenschain, SP TI Critical science issues for direct drive inertial fusion energy SO JOURNAL OF FUSION ENERGY LA English DT Article; Proceedings Paper CT Fusion Power Associates Annual Meeting and Symposium on Cost-Effective Steps to Fusion Power CY JAN 25-27, 1999 CL MARINA DEL REY, CALIFORNIA DE inertial fusion; krypton fluoride lasers AB There are several topics that require resolution prior to the construction of an Inertial Fusion Energy [IFE] laboratory Engineering Test Facility [ETF]: a pellet that produces high gain; a pellet fabrication system that cost-effectively and rapidly manufactures these pellets; a sufficiently uniform and durable high repetition-rate laser pellet driver; a practical target injection system that provides accurate pellet aiming; and, a target chamber that will survive the debris and radiation of repeated high-gain pellet implosions. In this summary we describe the science issues and opportunities that are involved in the design of a successful high gain direct drive Inertial Confinement Fusion [ICF] pellet. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. USN, Res Lab, LCP & FD, Washington, DC 20375 USA. RP Dahlburg, JP (reprint author), USN, Res Lab, Div Plasma Phys, Code 6730,4555 Overlook AU SW, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0164-0313 J9 J FUSION ENERG JI J. Fusion Energy PD SEP PY 1998 VL 17 IS 3 BP 227 EP 229 DI 10.1023/A:1021810413183 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 359EX UT WOS:000089599500012 ER PT J AU Sojka, JJ Schunk, RW Bowline, MD Chen, J Slinker, S Fedder, J Sultan, PJ AF Sojka, JJ Schunk, RW Bowline, MD Chen, J Slinker, S Fedder, J Sultan, PJ TI Ionospheric storm simulations driven by magnetospheric MHD and by empirical models with data comparisons SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY MAGNETIC-FIELD; WINTER F-REGION; EARTHS MAGNETOSPHERE; CONVECTION RESPONSE; ELECTRIC-FIELDS; SOLAR MINIMUM; JANUARY 14; TEMPERATURE; PASSAGE; PATTERN AB The results of two ionospheric simulations are compared with each other and with ionospheric observations of the southern hemisphere for the magnetic cloud passage event of January 14, 1988, For most of the event one simulation agrees with observations, while the other does not. Electric fields and electron precipitation patterns generated by a magnetospheric MHD model are used as inputs to a physical model of the ionosphere in the successful simulation, while empirical electric fields and electron precipitation are used as the inputs for the second simulation. In spite of ionospheric summer conditions a large and deep polar hole is developed. This is seen in the in situ plasma observations made by the DMSP-F8 satellite. The hole is surprisingly present during both northward and southward IMF conditions. It is deepest for the storm phase of the southward IMF period. A well-defined tongue of ionization is formed during this period. These features have been reproduced by the TDIM-MHD simulation and to a lesser extent by the TDIM-empirical simulation. However, the model simulations have not been able to generate a storm enhanced density where one was observed by DMSP-F8 during the initial phase of the storm. The differences between the two F region ionospheric simulations are attributed to differences in the magnetospheric electric fields and precipitation patterns used as inputs. This study provides a unique first simulation of the ionosphere's response to self-consistent electric field and auroral precipitation patterns over a 24-hour period that leads into a major geomagnetic storm. C1 Utah State Univ, Ctr Atmospher & Space Sci, Logan, UT 84322 USA. USN, Div Plasma Phys, Res Lab, Washington, DC 20375 USA. George Mason Univ, Inst Computat Sci & Informat, Fairfax, VA 22030 USA. USAF, Res Lab, Space Effects Div, GPSM, Hanscom AFB, MA 01731 USA. RP Sojka, JJ (reprint author), Utah State Univ, Ctr Atmospher & Space Sci, Logan, UT 84322 USA. NR 30 TC 14 Z9 14 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 SEP 1 PY 1998 VL 103 IS A9 BP 20669 EP 20684 DI 10.1029/98JA01744 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 118BG UT WOS:000075817300032 ER PT J AU Weiss, WR Ishii, KJ Hedstrom, RC Sedegah, M Ichino, M Barnhart, K Klinman, DM Hoffman, SL AF Weiss, WR Ishii, KJ Hedstrom, RC Sedegah, M Ichino, M Barnhart, K Klinman, DM Hoffman, SL TI A plasmid encoding murine granulocyte-macrophage colony-stimulating factor increases protection conferred by a malaria DNA vaccine SO JOURNAL OF IMMUNOLOGY LA English DT Article ID CD8+ T-CELLS; PLASMODIUM-YOELII SPOROZOITES; MARROW-DERIVED CELLS; INTERFERON-GAMMA; CIRCUMSPOROZOITE PROTEIN; CPG MOTIFS; INFECTED HEPATOCYTES; BACTERIAL-DNA; EXPRESSION VECTOR; ANTIBODY-RESPONSE AB Using the murine parasite Plasmodium yoelii (Py) as a model for malaria vaccine development, we have previously shown that a DNA plasmid encoding the Py circumsporozoite protein (PyCSP) can protect mice against sporozoite infection. We now report that mixing a new plasmid PyCSP1012 with a plasmid encoding murine granulocyte-macrophage colony-stimulating factor (GM-CSF) increases protection against malaria, and we have characterized in detail the increased immune responses due to GM-CSF, PyCSP1012 plasmid alone protected 28% of mice, and protection increased to 58% when GM-CSF was added (p < 0.0001). GM-CSF plasmid alone did not protect, and control plasmid expressing inactive GM-CSP did not enhance protection. GM-CSF plasmid increased Abs to PyCSP of IgG1, IgG2a, and IgG2b isotypes, but not IgG3 or IgM. IFN-gamma responses of CD8(+) T cells to the PyCSP 280-288 amino acid epitope increased but CTL activity did not change. The most dramatic changes after adding GM-CSF plasmid were increases in Ag-specific IL-2 production and CD4(+) T cell proliferation. We hypothesize that GM-CSF may act on dendritic cells to enhance presentation of the PyCSP Ag, with enhanced IL-2 production and CD4(+) T cell activation driving the increases in Abs and CD8(+) T cell function. Recombinant GM-CSP is already used in humans for medical purposes, and GM-CSF protein or plasmids may be useful as enhancers of DNA vaccines. C1 USN, Med Res Inst, Malaria Program, Rockville, MD 20852 USA. US FDA, Ctr Biol Evaluat & Res, Div Viral Prod, Sect Retroviral Immunol, Bethesda, MD 20892 USA. Univ Maryland, Baltimore, MD 21201 USA. Vical Inc, San Diego, CA 92121 USA. RP Weiss, WR (reprint author), USN, Med Res Inst, Malaria Program, 12300 Washington Ave, Rockville, MD 20852 USA. RI Ishii, Ken/B-1685-2012 OI Ishii, Ken/0000-0002-6728-3872 NR 49 TC 130 Z9 143 U1 1 U2 5 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD SEP 1 PY 1998 VL 161 IS 5 BP 2325 EP 2332 PG 8 WC Immunology SC Immunology GA 112UB UT WOS:000075511600032 PM 9725227 ER PT J AU Brandt, JE Medin, JA Rosler, ES Nelson, MC Chute, JP Hoffman, R AF Brandt, JE Medin, JA Rosler, ES Nelson, MC Chute, JP Hoffman, R TI Retroviral gene marking of human and non-human primate bone marrow progenitor and stem cells. SO JOURNAL OF INVESTIGATIVE MEDICINE LA English DT Meeting Abstract C1 Univ Illinois, Dept Med, Chicago, IL USA. USN, Med Res Inst, Bethesda, MD USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SLACK INC PI THOROFARE PA 6900 GROVE RD, THOROFARE, NJ 08086 USA SN 1081-5589 J9 J INVEST MED JI J. Invest. Med. PD SEP PY 1998 VL 46 IS 7 SU S BP 254A EP 254A PG 1 WC Medicine, General & Internal; Medicine, Research & Experimental SC General & Internal Medicine; Research & Experimental Medicine GA 113YX UT WOS:000075582600043 ER PT J AU Patrick, HJ Kersey, AD Bucholtz, F AF Patrick, HJ Kersey, AD Bucholtz, F TI Analysis of the response of long period fiber gratings to external index of refraction SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article DE chemical sensing; fiber gratings; index of refraction ID SENSORS; FILTERS AB This paper demonstrates that the change in wavelength of a long period fiber grating attenuation band with changes in external index of refraction can be enhanced by proper selection of the grating period. We calculate and experimentally verify that the wavelength shift caused by changing the external index from n = 1 to n = 1.44 of the attenuation band which appears in the 1400-1600 nm region in a 200-mu m period grating is four times that in a 350-mu m period grating, Changes in the spectrum over a wavelength range from 1100 to 1600 nm and 1 < n < 1.72 index range are also presented, and implications for grating design when enhanced or reduced index sensitivity is desired are discussed. Finally, we demonstrate the use of a highly index-sensitive long period fiber grating as a chemical concentration sensor. C1 USN, Res Lab, Washington, DC 20375 USA. RP Patrick, HJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 19 TC 492 Z9 514 U1 3 U2 35 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0733-8724 J9 J LIGHTWAVE TECHNOL JI J. Lightwave Technol. PD SEP PY 1998 VL 16 IS 9 BP 1606 EP 1612 DI 10.1109/50.712243 PG 7 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA 117GG UT WOS:000075772700009 ER PT J AU Singh, A Johnson, HM AF Singh, A Johnson, HM TI Conflict management diagnosis at project management organizations SO JOURNAL OF MANAGEMENT IN ENGINEERING LA English DT Article AB The world is full of conflict. Conflict is a matter of life, occurring as frequently as conversation in some cultures. The organization, like any culture, is subject to conflict. The project management organization is even more apt to suffer from conflict, with its constantly changing environment. However, the effects of conflict on the organization are not always negative. How is the individual project manager to know when his or her organization is in a healthy state of conflict? This paper presents one method that engineering managers can use to diagnose conflict in their organizations. The method has been applied to diagnose conflict within the State Public Agency (SPA), engaged in design and construction of civil engineering projects. The results indicate that SPA engineers predominantly use a problem-solving style to find mutual win-win resolutions to conflict, showing that SPA can thrive under conditions of conflict. The results also indicate, however, that SPA may be suffering from a lack of conflict. The average intensity of conflict perceived by all engineers is 1.40 on a scale of 0-4, or only a slight impact. Likewise, the frequency with which conflict occurs is low, at 1.59 on the same scale. Recommendations are provided for SPA. C1 Univ Hawaii, Dept Civil Engn, Honolulu, HI 96822 USA. USN, Aiea, HI 96701 USA. RP Singh, A (reprint author), Univ Hawaii, Dept Civil Engn, 2540 Dole St, Honolulu, HI 96822 USA. NR 13 TC 3 Z9 3 U1 1 U2 5 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 USA SN 0742-597X J9 J MANAGE ENG JI J. Manage. Eng. PD SEP-OCT PY 1998 VL 14 IS 5 BP 48 EP 63 DI 10.1061/(ASCE)0742-597X(1998)14:5(48) PG 16 WC Engineering, Industrial; Engineering, Civil SC Engineering GA 110RB UT WOS:000075393200036 ER PT J AU Root, WL Serakos, D AF Root, WL Serakos, D TI The state of dynamical input-output systems as an operator SO JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS LA English DT Article AB A causal input-output system operating for all time from the indefinite past to the indefinite future may be described by a function space for inputs, a function space for outputs, and a causal operator mapping the input space into the output space. The state of such a system at any instant is defined here as an operator from the space of possible future inputs to that of future outputs. This operator is called the natural state. The output space is taken to be a time-shift-invariant normed linear function space, and the input space is either also such a space or a time-shift-invariant subset thereof. There is flexibility allowed in the choice of these spaces. Both the input-output operator and the operator giving the natural state are themselves taken to be elements of normed linear spaces with one of a particular family of norms called N-power norms. The general development applies to nonlinear and time-varying systems. Continuity and boundedness of the natural state (as an operator) and properties of the natural state and its trajectory as related to the input-output description of the system are investigated. Two examples are presented. (C) 1998 Academic Press. C1 Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA. USN, Ctr Surface Warfare, Combat Syst Dept, Dahlgren, VA 22448 USA. RP Serakos, D (reprint author), Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-247X J9 J MATH ANAL APPL JI J. Math. Anal. Appl. PD SEP 1 PY 1998 VL 225 IS 1 BP 224 EP 248 DI 10.1006/jmaa.1998.6017 PG 25 WC Mathematics, Applied; Mathematics SC Mathematics GA 115YP UT WOS:000075694200012 ER PT J AU Leffler, CT Dembert, ML AF Leffler, CT Dembert, ML TI Posttraumatic stress symptoms among US Navy divers recovering TWA Flight 800 SO JOURNAL OF NERVOUS AND MENTAL DISEASE LA English DT Article ID DISASTER; BODIES; DEATH C1 USN, Med Ctr, Dept Psychiat, Portsmouth, VA 23708 USA. Dept Med, Mobile Diving & Salvage Unit 2, Norfolk, VA USA. RP Dembert, ML (reprint author), USN, Med Ctr, Dept Psychiat, Portsmouth, VA 23708 USA. NR 13 TC 27 Z9 27 U1 3 U2 3 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0022-3018 J9 J NERV MENT DIS JI J. Nerv. Ment. Dis. PD SEP PY 1998 VL 186 IS 9 BP 574 EP 577 DI 10.1097/00005053-199809000-00009 PG 4 WC Clinical Neurology; Psychiatry SC Neurosciences & Neurology; Psychiatry GA 116XW UT WOS:000075751200009 PM 9741564 ER PT J AU Lin, S Gensburg, L Marshall, EG Roth, GB Dlugosz, L AF Lin, S Gensburg, L Marshall, EG Roth, GB Dlugosz, L TI Effects of maternal work activity during pregnancy on infant malformations SO JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL MEDICINE LA English DT Article ID LOW-BIRTH-WEIGHT; CONGENITAL-DEFECTS; WOMEN AB This article examines the association between two birth defects, neural tube defects and oral cleft defects, and maternal physical work demands during the per periconceptional period. A case-control st study was conducted by comparing exposure characteristics of mothers of malformed infants, as ascertained from the New York State Congenital Malformations Registry (n = 520), with mothers of non-malformed infants (n = 1154). Case groups were further subdivided on whether infants had additional defects. Occupational exposure information was collected from a self-administered questionnaire, and demographic variables from vital records, The results showed no general differences between cases and controls in most variables. However, those infants with cleft defects plus additional defects tended to have a marginally increased risk (odds ratio = 1.76; 95 % confidence interval, 1.02-3.21) in relation to maternal jobs requiring standing (greater than or equal to 75 % of time). We suggest that exposure assessment be improved and defects subdivided for future studies. C1 Bur Environm & Occupat Epidemiol, New York State Dept Hlth, Albany, NY 12203 USA. Bur Occupat Hlth, New York State Dept Hlth, Albany, NY 12203 USA. USN, Geocenters Inc, Hlth Res Ctr, San Diego, CA USA. RP Lin, S (reprint author), Bur Environm & Occupat Epidemiol, New York State Dept Hlth, 1215 Western Ave,Room 105, Albany, NY 12203 USA. OI Lin, Shao/0000-0002-5535-7504 NR 25 TC 9 Z9 10 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 1076-2752 J9 J OCCUP ENVIRON MED JI J. Occup. Environ. Med. PD SEP PY 1998 VL 40 IS 9 BP 829 EP 834 DI 10.1097/00043764-199809000-00013 PG 6 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 121MG UT WOS:000076017100012 PM 9777568 ER PT J AU Harff, B Gurr, TR AF Harff, B Gurr, TR TI Systematic early warning of humanitarian emergencies SO JOURNAL OF PEACE RESEARCH LA English DT Article; Proceedings Paper CT Conference on the Political Economy of Humanitarian Emergencies CY OCT 06-08, 1996 CL HELSINKI, FINLAND SP World Inst Dev Econ Res ID CONFLICT; DEMOCRACY; PEOPLES AB More than 60 communal minorities were victimized as a result of internal wars and stare failures between 1980 and 1996. Two theoretical models provide the basis for systematic early warning of future victimization of communal and political groups. The potential for communal rebellion is said to be a joint function of group incentives, group capacity, and opportunities for collective action. Indicators of these concepts from the Minorities at Risk project are used to identify 73 groups at high risk of communal rebellion in the late 1990s. Genocide and politicide are attributed to background conditions (e.g. political upheaval), intervening conditions (e.g. elite fragmentation), and a short-term increase in theoretically pre-specified accelerators. Monitoring of accelerators and de-accelerators in potential crisis situations provides a link between risk assessments based on structural models and early warnings of use to national and international policy-makers. The approach is illustrated by an analysis of accelerators prior to the occurrence of the 1994 genocide in Rwanda. C1 USN Acad, Annapolis, MD 21402 USA. Univ Maryland, College Pk, MD 20742 USA. RP Harff, B (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 44 TC 28 Z9 28 U1 12 U2 35 PU SAGE PUBLICATIONS LTD PI LONDON PA 6 BONHILL STREET, LONDON, ENGLAND EC2A 4PU SN 0022-3433 J9 J PEACE RES JI J. Peace Res. PD SEP PY 1998 VL 35 IS 5 BP 551 EP 579 DI 10.1177/0022343398035005002 PG 29 WC International Relations; Political Science SC International Relations; Government & Law GA 129DX UT WOS:000076449000002 ER PT J AU Meyer, GA Blum, NJ Hitchcock, W Fortina, P AF Meyer, GA Blum, NJ Hitchcock, W Fortina, P TI Absence of the fragile X CGG trinucleotide repeat expansion in girls diagnosed with a pervasive developmental disorder SO JOURNAL OF PEDIATRICS LA English DT Article ID INFANTILE-AUTISM; MENTAL-RETARDATION; SWEDISH MULTICENTER; CHILDREN; PREVALENCE; POPULATION; ASSOCIATION; INDIVIDUALS; CHROMOSOME; FREQUENCY AB The purpose of this study was to determine the prevalence of the fragile X (FRAX) CGG trinucleotide expansion in a population of young girls (n = 45) diagnosed with pervasive developmental disorder (PDD). Their mean age was 43.7 months (range, 25 to 132 months). Diagnoses included autistic disorder (n = 20), PDD (n = 23), and Asperger's syndrome (n = 2). Molecular FRAX testing was performed on all patients by using the Southern gene blot technique. Genomic DNA was digested with both EcoRI and EagI, fractionated on agarose gel, and blotted and probed with the radiolabeled StB12.3 FMR-1 probe. None Of the subjects were found to have an expansion of CGG in either the 2.8 kb or 5.2 kb fragments. A 95% CI, for the prevalence of the FRAX mutation in female subjects with PDD, has an upper bound of 2.9%. We conclude that the prevalence of FRAX positivity in girls with PDD is lower than previously reported. This raises the question of whether any association between FRAX and PDD in female subjects is specific to PDD or is related rather to the presence of mental retardation. C1 USN, Med Ctr Portsmouth, Dept Pediat, Portsmouth, VA 23708 USA. Childrens Seashore house, Div Child Dev & Rehabil, Philadelphia, PA USA. Childrens Hosp Philadelphia, Dept Pathol & Clin Labs, Philadelphia, PA 19104 USA. Univ Penn, Sch Med, Dept Pediat, Philadelphia, PA 19104 USA. RP Meyer, GA (reprint author), USN, Med Ctr Portsmouth, Dept Pediat, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 36 TC 4 Z9 4 U1 1 U2 1 PU MOSBY-ELSEVIER PI NEW YORK PA 360 PARK AVENUE SOUTH, NEW YORK, NY 10010-1710 USA SN 0022-3476 EI 1097-6833 J9 J PEDIATR-US JI J. Pediatr. PD SEP PY 1998 VL 133 IS 3 BP 363 EP 365 DI 10.1016/S0022-3476(98)70270-7 PG 3 WC Pediatrics SC Pediatrics GA 117GJ UT WOS:000075772900013 PM 9738717 ER PT J AU Eichmiller, FC Hoffman, KM Guiseppetti, AA Wray, MM Avers, RJ AF Eichmiller, FC Hoffman, KM Guiseppetti, AA Wray, MM Avers, RJ TI Acid-assisted consolidation of silver alloys for direct fillings SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE acid-assisted consolidation; cold-welding; consolidated silver ID MERCURY AB Silver-rich metal powders cold-welded by consolidation have been investigated as possible direct dental filling material. The surface of the silver powder must undergo an acid treatment to remove existing contaminants and prevent formation of new surface contaminants during consolidation. This study was designed to investigate the effect of the acid treatment on the strength of the consolidated alloy, its reactivity with the surrounding tooth structure, and its reactions with certain cavity liners. This study investigated the effects of pH and concentration of fluoboric acid on the flexural strength of silver powder consolidated into rectangular beams in a partial 4 x 4 design. The study also assessed, by visible and scanning electron microscopy, what effect the acid-treated powders had on dentin that had been pre-coated with different cavity liners. Mean flexural strengths for beams consolidated using dental hand instruments were in the range (77.0 +/- 9.28) MPa to (166.1 +/- 17.6) MPa, where the quoted uncertainties are standard uncertainties (i.e., one standard deviation estimates). ANOVA indicated that fluoboric acid pH was highly significant (p <0.0001) with lower pH values resulting in higher flexural strength. Concentration alone was not a significant factor for flexural strengths, but there was a significant interaction between concentration and pH (p < 0.0001). Microscopy revealed that the acid-treated silver powder demineralized approximately 2 mu m of dentin when used with no liner. The use of copal or polyamide varnishes eliminated most of this demineralization, but the use of a dentin adhesive liner resulted in some dislodgment and breakdown of the adhesive film by the acid. The results of this study indicate that this silver powder when treated with dilute fluoboric acid at a pH of approximately 1.0 can result in a filling material with strength equivalent to currently used conventional amalgam. The demineralization of tooth structure appears to be minimal and can be eliminated with the use of cavity liners. C1 Natl Inst Stand & Technol, Amer Dent Assoc Hlth Fdn, Paffenbarger Res Ctr, Gaithersburg, MD 20899 USA. USN, Sch Dent, Gaithersburg, MD 20899 USA. RP Eichmiller, FC (reprint author), Natl Inst Stand & Technol, Amer Dent Assoc Hlth Fdn, Paffenbarger Res Ctr, Gaithersburg, MD 20899 USA. NR 13 TC 1 Z9 1 U1 1 U2 2 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD SEP-OCT PY 1998 VL 103 IS 5 BP 511 EP 516 DI 10.6028/jres.103.031 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 143JZ UT WOS:000077253200004 PM 28009374 ER PT J AU Moore, FG McInville, RM Hymer, TC AF Moore, FG McInville, RM Hymer, TC TI Review and extension of computational methods for noncircular cross-sectional weapons SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Review AB A review of current state-of-the-art methods for computing aerodynamics of noncircular cross-sectional weapon concepts has been performed. In addition, an improved engineering method has been developed to compute aerodynamics of these nonaxisymmetric body configurations. The improved method is based on extending current state-of-the-art methods for computing aerodynamics of noncircular wing-body shapes based on circular wing-body methods. Specific additions to the state-of the-art methods currently in use include extensions to a broader class of cross-sectional bodies and to a higher angle of attack; extensions to allow improved accuracy at low crossflow Mach number and to allow body cross-sectional shape to impact the critical crossflow Reynolds number; and a method to treat wing-body interference factor corrections as a function of body geometry, Mach number, and angle of attack. The new methods were applied to a broad class of noncircular body alone and wing-body configurations for which wind-tunnel data were available. In general, results for normal force, axial force, and center-of-pressure predictions were quite good for a semiempirical methodology, over the Mach number and angle-of-attack range where data were available. Range of variables included Mach numbers as low as 0.3 and as high as 14 and angles of attack to 60 deg. C1 USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Moore, FG (reprint author), USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. NR 34 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD SEP-OCT PY 1998 VL 35 IS 5 BP 585 EP 597 DI 10.2514/2.3380 PG 13 WC Engineering, Aerospace SC Engineering GA 129WT UT WOS:000076487600001 ER PT J AU Poston, WL Wegman, EJ Solka, JL AF Poston, WL Wegman, EJ Solka, JL TI D-optimal design methods for robust estimation of multivariate location and scatter SO JOURNAL OF STATISTICAL PLANNING AND INFERENCE LA English DT Article DE minimum volume ellipsoid; MVE; experimental design; D-optimal design; information matrix; robust estimation AB Using ideas and techniques from related disciplines frequently proves productive and often yields new insights and methods. In this paper, a method from experimental design is applied to the robust estimation of multivariate location and scatter. In particular, the procedure of determining discrete D-optimal designs is applied to the problem of finding the robust estimator called the minimum volume ellipsoid (MVE). The objective of the D-optimal design problem is to select h points to include in the design from a set of n candidate points such that the determinant of the information matrix is maximized. To calculate the MVE, a subset of h points must be selected where the volume of the ellipsoid covering them is the minimum over all possible subsets of size h. We demonstrate the relationship of these optimization problems and propose a technique to select the subset of points for both applications. The subset selection method is applied to several regression data sets where the true MVE estimate is known. (C) 1998 Published by Elsevier Science B.V. AII rights reserved. C1 USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. George Mason Univ, Ctr Computat Stat, Fairfax, VA 22030 USA. USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. NR 15 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3758 J9 J STAT PLAN INFER JI J. Stat. Plan. Infer. PD SEP 1 PY 1998 VL 73 IS 1-2 BP 205 EP 213 DI 10.1016/S0378-3758(98)00062-7 PG 9 WC Statistics & Probability SC Mathematics GA 130NX UT WOS:000076527100018 ER PT J AU Joyce, JA AF Joyce, JA TI Experimental justification for proposed changes to the measurement of K-Ic using ASTM E 399 SO JOURNAL OF TESTING AND EVALUATION LA English DT Article DE fracture mechanics; linear fracture mechanics; crack initiator; stress intensity factor; size requirements; side grooves; T-stress ID SPECIMEN GEOMETRIES AB During the past five years considerable effort has been devoted to developing a fracture toughness measurement standard that combines the linear elastic stress intensity factor at the onset of crack extension, K-Ic, and the elastic-plastic fracture toughness measurement quantities, namely, J(Ic), the J resistance curve (J-R curve), and the corresponding crack tip opening displacement resistance curve (CTOD-R curve). The objective of this effort was to allow the engineer to start with one specimen geometry, conduct a specified test, develop either a K-Q, or a J(Q)-R curve, and then, after application of the relevant size requirements, obtain a valid fracture toughness result. At present, different specimens are required by E 399 and E 1737 (the combination and replacement of E 813 and E 1152), and if the engineer uses the E 399 specimen geometry and test procedure and subsequently finds that the measured K-Q fails the E 399 size requirements, new specimens must be machined and tested according to E 1737 to obtain valid fracture toughness measurements. This paper describes experimental tests that have been conducted in parallel with the development of the new ASTM Standard E 1820-97, a combined fracture toughness test standard that is intended to address this problem. These experimental results show that the standard J integral specimen, incorporating load line crack mouth opening displacement measurements and side grooves, can be used to obtain K-Ic as presently defined by ASTM E 399. The use of larger a/W ranges is also supported by these results as long as the basic size requirements of E 399 are met and applied to both the specimen crack length and remaining ligament as well as to the specimen gross thickness. C1 USN Acad, Annapolis, MD 21402 USA. RP Joyce, JA (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 7 TC 3 Z9 3 U1 0 U2 3 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0090-3973 J9 J TEST EVAL JI J. Test. Eval. PD SEP PY 1998 VL 26 IS 5 BP 455 EP 462 PG 8 WC Materials Science, Characterization & Testing SC Materials Science GA 123XU UT WOS:000076151600006 ER PT J AU Yang, TC Yates, T AF Yang, TC Yates, T TI Matched-beam processing: Application to a horizontal line array in shallow water SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SOURCE LOCALIZATION; DEPTH; INVERSION; MISMATCH; RANGE AB Matched-beam processing of a horizontal line array in a multipath shallow-water environment is presented. With conventional beamforming, the signal is split into several beams when the target is away from the broadside direction. This can result in signal gain degradation and severe bearing bias. Matched-beam processing is matched-field processing applied in the beam domain. It offers an efficient and robust approach for correcting bearing errors and signal gain degradation of horizontal Line arrays in shallow water. It is based on conventional beams but extends conventional processing to incorporate full-field processing. It is applicable to existing systems where the conventional beam outputs are the only data readily available. Many of the signal processing algorithms for horizontal arrays, such as adaptive beamforming for nulling strong interferences, can be incorporated directly into matched-beam processing. Target bearing tracking and depth discrimination are illustrated using matched-beam processing for a horizontal line array. [S0001-4966(98)03009-4]. C1 USN, Res Lab, Washington, DC 20375 USA. Vector Res Co, Rockville, MD 20852 USA. RP Yang, TC (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM yang@wave.nrl.navy.mil NR 27 TC 13 Z9 14 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 SEP PY 1998 VL 104 IS 3 BP 1316 EP 1330 DI 10.1121/1.424341 PN 1 PG 15 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 118WW UT WOS:000075864800020 ER PT J AU Kulkarni, RS Siegmann, WL Collins, MD McDonald, BE AF Kulkarni, RS Siegmann, WL Collins, MD McDonald, BE TI Nonlinear pulse propagation in shallow-water environments with attenuating and dispersive sediments SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID ORDER PARABOLIC EQUATIONS; TIME-DOMAIN SOLUTION; ACOUSTIC PROPAGATION; ELASTIC MEDIA; SEA-BOTTOM; OCEAN; FREQUENCY; SOUND AB A hybrid treatment for wide-angle paraxial propagation that includes effects of both sediment dispersion and weak nonlinearity has been developed. A. Fourier transform approach is used to combine effects of refraction, diffraction, and sediment dispersion in the frequency domain, and nonlinear effects in the time domain. A nonlinear wide-angle time-domain equation developed recently is first split into linear and nonlinear component equations. The linear equation is decomposed into its discrete frequency-domain counterparts. Sediment attenuation and dispersion are incorporated using a complex wave number along with a frequency-dependent formula for phase velocity to satisfy causality. The numerical implementation consists of first decomposing a broadband source into its frequency components and propagating them over a range step using a wide-angle parabolic equation. Fourier synthesis is used to reconstruct the signal which is then corrected to account for nonlinear effects in the time domain. Numerical examples illustrating the effects of dispersion and nonlinearity on shallow-water wide-angle propagation are presented and compared with available results. (C) 1998 Acoustical Society of America. [S0001-4966(98)00709-7]. C1 Rensselaer Polytech Inst, Troy, NY 12180 USA. USN, Res Lab, Washington, DC 20375 USA. RP Kulkarni, RS (reprint author), Rensselaer Polytech Inst, Troy, NY 12180 USA. NR 41 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 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD SEP PY 1998 VL 104 IS 3 BP 1356 EP 1362 DI 10.1121/1.424344 PN 1 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 118WW UT WOS:000075864800023 ER PT J AU Mendel, LL Hamill, BW Hendrix, JE Crepeau, LJ Pelton, JD Miley, MD Kadlec, EE AF Mendel, LL Hamill, BW Hendrix, JE Crepeau, LJ Pelton, JD Miley, MD Kadlec, EE TI Speech intelligibility assessment in a helium environment. II. The speech intelligibility index SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The Speech Intelligibility Index (SII) was measured for Navy divers participating in two saturation deep dives and for a group of nondivers to test different communication systems and their components. These SIIs were validated using the Speech Perception in Noise (SPIN) test and the Griffiths version of the Modified Rhyme Test (GMRT). Our goal was to determine if either of these assessments was sensitive enough to provide an objective measure of speech intelligibility when speech was processed through different helmets and helium speech unscramblers (HSUs). Results indicated that SII values and percent intelligibility decreased incrementally as background noise level increased. SIIs were very reliable across the different groups of subjects indicating that the SII was a strong measurement for predicting speech intelligibility to compare linear system components such as helmets. The Sn was not useful in measuring intelligibility through nonlinear devices such as HSUs. The speech intelligibility scores on the GMRT and SPIN tests were useful when the system component being compared had a large measurable difference, such as in helmet type. However, when the differences were more subtle, such as differences in HSUs, neither the SPIN nor the GMRT appeared sensitive enough to make such distinctions. These results have theoretical as well as practical value for measuring the quality and intelligibility of helium speech enhancement systems. (C) 1998 Acoustical Society of America. [S0001-4966(98)03109-9] C1 Univ Mississippi, Dept Communicat Disorders, Ctr Speech & Hearing Res, University, MS 38677 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Oxford Signal Proc, Oxford, MS 38655 USA. USN, Expt Diving Unit, Panama City, FL 32407 USA. XN Technol, Cheney, WA 99004 USA. Univ Georgia, Athens, GA 30602 USA. RP Mendel, LL (reprint author), Univ Mississippi, Dept Communicat Disorders, Ctr Speech & Hearing Res, University, MS 38677 USA. NR 15 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 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD SEP PY 1998 VL 104 IS 3 BP 1609 EP 1615 PN 1 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 118WW UT WOS:000075864800052 PM 9745744 ER PT J AU Gaunaurd, GC AF Gaunaurd, GC TI Analysis and comparison of recent resonance scattering formulations by M.S. Choi et al. with earlier, traditional RST works SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Letter ID BACKGROUND COEFFICIENTS; CYLINDRICAL-SHELLS; ELASTIC SHELLS; SPECTROGRAMS; SOUND AB Some comparisons are studied between several recent (1997 and 1998) formulations of acoustic resonance scattering, by M. S. Choi et al. and other earlier, traditional ones. In the practical cases here analyzed, the recent formulations are: (a) more complicated; (b) of purely formal character; (c) make use of information not known or available a priori; (d) eventually reduce to the traditional ones; and (e) seem to offer little new practical advantages. Finally, none of these formulations has been used for target identification purposes, which is the essential underlying reason for these investigations. [S0001-4966(98)05608-2] C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. RP Gaunaurd, GC (reprint author), USN, Ctr Surface Warfare, Carderock Div, Code 684,9500 MacArthur Blvd, W Bethesda, MD 20817 USA. 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 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD SEP PY 1998 VL 104 IS 3 BP 1720 EP 1722 DI 10.1121/1.424385 PN 1 PG 3 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 118WW UT WOS:000075864800064 ER PT J AU Forst, D Li, JF Xu, ZK AF Forst, D Li, JF Xu, ZK TI Incommensurately modulated polar structures in antiferroelectric tin-modified lead zirconate titanate: II, dependence of structure-property relations on tin content SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID PHASE-TRANSITIONS; CERAMICS; TRANSFORMATION; IMPURITIES; ROTATIONS; NIOBATE; DEFECT AB Studies of the structure-property relations in Pb0.98Nb0.02-[(Zr1-xSnx)(0.97)Ti-3](1-z)O-3 (PZST x/3/2) were performed for 0 < x < 0.50 by transmission electron microscopy, dielectric spectroscopy, and electrically induced polarization and strain methods. As the tin content increased, a general sequence of changes in phase stability was observed, including (i) a ferroelectric rhombohedral (FEr) phase (x < 0.15), (ii) a coexistence of FEr and antiferroelectric incommensurate (AFE(in)) states (x = 0.15), and (iii) an AFE(in) state (x > 0.15), Evidence will be presented that incommensurately modulated structures become pinned into long-lived metastable states by quenched tin impurities, rather than evolving toward a commensurate phase. Maximum electrically induced strains (epsilon) and polarizations (P) were found in the compositional range of x approximate to 0.15, where FEr and AFE(in) regions coexisted, Values of epsilon as large as 0.5% were found at field strengths of <80 kV/cm, In addition, these studies demonstrated evidence for two electrically induced phase transitions (x = 0.15): (i) an antiferroelectric-ferroelectric (AFE-FE) transition near 40 kV/cm, and (ii) a secondary ferroelectric-ferroelectric (FE-FE) transition near 60-80 kV/cm, The dominate contribution to epsilon was associated with the secondary transition, whereas the dominate contribution to P was associated with the first. For x < 0.15, evidence of an induced FE-FE transition was found, For x > 0,15, an induced AFE-FE transition was evident, However, no indications of a secondary FE-FE transition were observed. Large epsilon values were not induced until field levels significantly greater than that required to induced polarization saturation were obtained, which indicates a decoupling of epsilon and P. C1 Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. USN, Undersea Warfare Ctr, Transduct Res & Dev Branch, Newport, RI 02841 USA. RP Forst, D (reprint author), Motorola Inc, Div Ceram, Albuquerque, NM USA. OI XU, Zhengkui/0000-0002-7465-8513 NR 31 TC 9 Z9 9 U1 5 U2 14 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD SEP PY 1998 VL 81 IS 9 BP 2225 EP 2236 PG 12 WC Materials Science, Ceramics SC Materials Science GA 121AB UT WOS:000075989000002 ER PT J AU Afanas'ev, VV Stesmans, A Revesz, AG Hughes, HL AF Afanas'ev, VV Stesmans, A Revesz, AG Hughes, HL TI Oxygen vacancies in SiO2, layers an Si produced at high temperature SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID SIMOX BURIED OXIDES; SI/SIO2/SI STRUCTURES; IMPLANTATION; GENERATION; DEFECTS; INJECTION; OXIDATION; TRAPS AB Oxygen vacancy centers in buried oxide (BOX) layers of Si/SiO2/Si structures produced by implantation of oxygen ions into silicon and subsequent internal thermal oxidation (ITOX) were studied by monitoring hole trapping and paramagnetic properties. During the ITOX process the BOX layer is augmented by thermally grown oxide. We have found that this additional buried thermal oxide layer has nearly the same density of O vacancies as the initial buried oxide, and an even higher number of oxygen vacancy clusters (E-delta' centers), even though the superficial Si layer was saturated by oxygen. This result suggests the generation of oxygen vacancies in Si-confined SiO2 to be due to temperature driven interaction between Si and SiO2. The clustering of the oxygen vacancies observed in all the high temperature oxides (both buried and unconfined), and the inverted relationship between the vacancy charge and its paramagnetic state point toward changes in the SiO2 network structure as compared to the conventional oxides. C1 Univ Louvain, Dept Phys, B-3001 Louvain, Belgium. Revesz Associates, Bethesda, MD 20817 USA. USN, Res Lab, Washington, DC 20375 USA. RP Afanas'ev, VV (reprint author), Univ Louvain, Dept Phys, B-3001 Louvain, Belgium. NR 28 TC 10 Z9 10 U1 0 U2 0 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD SEP PY 1998 VL 145 IS 9 BP 3157 EP 3160 DI 10.1149/1.1838779 PG 4 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 112DR UT WOS:000075479300031 ER PT J AU Ehrlich, Y Cohen, C Kaganovich, D Zigler, A Hubbard, RF Sprangle, P Esarey, E AF Ehrlich, Y Cohen, C Kaganovich, D Zigler, A Hubbard, RF Sprangle, P Esarey, E TI Guiding and damping of high-intensity laser pulses in long plasma channels SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID PARTIALLY STRIPPED PLASMAS; WAVE-GUIDE; HARMONIC-GENERATION; ELECTRON ACCELERATION; PROPAGATION; BEAMS; STABILITY; GASES; IONIZATION AB An experimental demonstration is presented of large-distance (up to 6.6 cm, or 75 Rayleigh lengths) guiding of high-intensity (>10(16) W cm(-2)) laser pulses in a plasma channel produced by a capillary discharge. Theory and simulation are used to describe damped oscillations that occur in the laser spot size as well as laser-induced ionization within the channel. Good agreement is obtained between theory, simulation, and experiment. (C) 1998 Optical Society of America. C1 Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. RP Ehrlich, Y (reprint author), Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. OI Kaganovich, Dmitri/0000-0002-0905-5871 NR 41 TC 41 Z9 41 U1 0 U2 3 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 SEP PY 1998 VL 15 IS 9 BP 2416 EP 2423 DI 10.1364/JOSAB.15.002416 PG 8 WC Optics SC Optics GA 117VK UT WOS:000075803200010 ER PT J AU Lavernia, EJ Kabacoff, L AF Lavernia, EJ Kabacoff, L TI Thermal spray processing of nanostructured materials SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Editorial Material C1 Univ Calif Irvine, Irvine, CA 92717 USA. Off Naval Res, Arlington, VA 22217 USA. RP Lavernia, EJ (reprint author), Univ Calif Irvine, Irvine, CA 92717 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD SEP PY 1998 VL 7 IS 3 BP 291 EP 291 DI 10.1007/s11666-998-0053-9 PG 1 WC Materials Science, Coatings & Films SC Materials Science GA 119WF UT WOS:000075920600001 ER PT J AU Ransom, B Shea, KF Burkett, PJ Bennett, RH Baerwald, R AF Ransom, B Shea, KF Burkett, PJ Bennett, RH Baerwald, R TI Comparison of pelagic and nepheloid layer marine snow: implications for carbon cycling SO MARINE GEOLOGY LA English DT Article DE nepheloid layer; marine snow; organic carbon; continental margin; TEM ID CALIFORNIA CURRENT SYSTEM; CONTINENTAL-MARGIN; ORGANIC-MATTER; WATER COLUMN; PARTICLES; SEDIMENTS; NORTHERN; OCEAN; SHELF; TRANSPORT AB Marine snow from upper and mid-water (i.e., pelagic) depths on the California margin is texturally and compositionally different from that traveling in the nepheloid layer. Transmission electron microscopy shows that pelagic marine snow consists primarily of bioclasts (e.g., diatom frustules, foram tests), organic matter, and microbes. These components are entrained as discrete particles or small aggregates (less than or equal to 10 mu m in diameter) in a loose network of exocellular, muco-polysaccharide material. Clays are infrequent but, when present, are constituents of comparatively compact organic-rich microaggregates. Microbes are abundant and appear to decrease in number with increasing water depth. In contrast, marine snow aggregates collected from just above the sea floor in the nepheloid layer are assemblages of clay particles, clay flocs, and relatively dense clay-organic-rich microaggregates in an exocellular organic matrix. Bioclasts and microorganisms occur only rarely. The prevalence of clay-organic-rich aggregates in the nepheloid layer suggests that, prior to final deposition and burial, marine snow from the pelagic zone is subject to disaggregation and recombination with terrigenous detrital material near or at the sea floor. Results have significant implications for the accumulation and burial rates of organic carbon on continental margins and the aging and bioavailability of sedimentary organic matter. Samples examined were collected offshore of northern and central California. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. SEAPROBE Inc, Picayune, MS 39566 USA. Univ New Orleans, Dept Biol, New Orleans, LA 70148 USA. RP Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. EM ransom@ucsd.edu NR 44 TC 39 Z9 43 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0025-3227 EI 1872-6151 J9 MAR GEOL JI Mar. Geol. PD SEP PY 1998 VL 150 IS 1-4 BP 39 EP 50 DI 10.1016/S0025-3227(98)00052-8 PG 12 WC Geosciences, Multidisciplinary; Oceanography SC Geology; Oceanography GA 136ZU UT WOS:000076889600003 ER PT J AU Briscoe, MG Kinder, TH AF Briscoe, MG Kinder, TH TI ONRs accelerated research initiatives (ARIs) SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Editorial Material C1 Off Naval Res, Ocean Atmosphere & Space Sci & Technol Dept, Arlington, VA 22217 USA. RP Briscoe, MG (reprint author), Off Naval Res, Ocean Atmosphere & Space Sci & Technol Dept, Arlington, VA 22217 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 USA SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD FAL PY 1998 VL 32 IS 3 BP 81 EP 84 PG 4 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 148LH UT WOS:000077506400010 ER PT J AU Sperling, LC Mezebish, DS AF Sperling, LC Mezebish, DS TI Hair diseases SO MEDICAL CLINICS OF NORTH AMERICA LA English DT Article ID ANDROGENIC DISORDERS; ALOPECIA; WOMEN; HISTOPATHOLOGY; DIAGNOSIS; BIOLOGY AB A few common causes of hair loss account for the vast majority of cases. A well-directed history and simple physical examination is often sufficient to make a diagnosis. Laboratory testing is often unnecessary. A scalp biopsy can be useful, but only if processed and interpreted correctly. Androgenetic alopecia, alopecia areata, senescent alopecia, telogen effluvium, traction alopecia, trichotillomania, and cosmetic hair damage are common causes of nonscarring alopecia. Discoid lupus erythematosus, lichen planopilaris, and central, centrifugal scarring alopecia are the most common forms of scarring hair loss. C1 Uniformed Serv Univ Hlth Sci, Dept Dermatol, Bethesda, MD 20814 USA. USN, Natl Med Ctr, Dept Dermatol, Bethesda, MD 20084 USA. Walter Reed Army Med Ctr, Dermatol Serv, Washington, DC 20307 USA. RP Sperling, LC (reprint author), Uniformed Serv Univ Hlth Sci, Dept Dermatol, 4301 Jones Bridge Rd, Bethesda, MD 20814 USA. NR 18 TC 19 Z9 19 U1 0 U2 2 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0025-7125 J9 MED CLIN N AM JI Med. Clin. N. Am. PD SEP PY 1998 VL 82 IS 5 BP 1155 EP + DI 10.1016/S0025-7125(05)70408-9 PG 16 WC Medicine, General & Internal SC General & Internal Medicine GA 124MZ UT WOS:000076187500009 PM 9769798 ER PT J AU Pande, CS Masumura, RA Marsh, SP AF Pande, CS Masumura, RA Marsh, SP TI The sweep constant concept in phase coarsening SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID GRAIN-GROWTH AB An expression for sweep constant originally introduced for grain growth is derived in terms of the parameters of the size distribution. The sweep constant is extended to the phenomenon of phase coarsening. It is shown that a relationship exists between the sweep constant, coarsening rate, and volume fraction of the particles undergoing coarsening. C1 USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. RP Pande, CS (reprint author), USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 1998 VL 29 IS 9 BP 2395 EP 2398 DI 10.1007/s11661-998-0115-0 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 120WX UT WOS:000075981400016 ER PT J AU Dutta, I Quiles, FN McNelley, TR Nagarajan, R AF Dutta, I Quiles, FN McNelley, TR Nagarajan, R TI Optimization of the strength-fracture toughness relation in particulate-reinforced aluminum composites via control of the matrix microstructure SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID GRAIN-SIZE; MECHANICAL-PROPERTIES; AGING RESPONSE; DEFORMATION; GROWTH; CAST; PRECIPITATION AB The evolution of the microstructure and mechanical properties of a 17.5 vol. pet SiC particulate-reinforced aluminum alloy 6092-matrix composite has been studied as a function of postfabrication processing and heat treatment. It is demonstrated that, by the control of particulate distribution, matrix grain, and substructure and of the matrix precipitate state, the strength-toughness combination in the composite can be optimized over a wide range of properties, without resorting to unstable, underaged (UA) matrix microstructures, which are usually deemed necessary to produce a higher fracture toughness than that displayed in the peak-aged condition. Further, it is demonstrated that, following an appropriate combination of thermomechanical processing and unconventional heat treatment, the composite may possess better stiffness, strength, and fracture toughness than a similar unreinforced alloy. In the high- and low-strength matrix microstructural conditions, the matrix grain and substructure were found to play a substantial role in determining fracture properties. However, in the intermediate-strength regime, properties appeared to be optimizable by the utilization of heat treatments only. These observations are rationalized on the basis of current understanding of the grain size dependence of fracture toughness and the detailed microstructural features resulting from thermomechanical treatments. C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. USN, Postgrad Sch, Dept Engn Mech, Washington, DC USA. RP Dutta, I (reprint author), USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. NR 48 TC 9 Z9 9 U1 1 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 1998 VL 29 IS 9 BP 2433 EP 2446 DI 10.1007/s11661-998-0119-9 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 120WX UT WOS:000075981400020 ER PT J AU Conard, R Emanuel, R AF Conard, R Emanuel, R TI Aggressive and impulsive behavior in military psychiatric inpatients SO MILITARY MEDICINE LA English DT Article ID PREDICTORS; SUICIDE; RISK AB Objective: To determine if a history of aggressive/impulsive behavior adversely affected the return to full duty of a military psychiatric inpatient population, Method: Charts were reviewed for aggressive/impulsive behavior as indicated by self-report on a standardized admission form and by history in 211 consecutive admissions pooled from two separate 2-month intervals during a 9-month period. Results: Seventy-three percent of the population was between the ages of 17 and 24 years. Sixty- eight percent of the population reported a history of at least one school suspension/expulsion, arrest, or military nonjudicial punishment (males, 74%; females, 45%). Seven percent of patients reporting aggressive/impulsive behavior were returned to full duty unconditionally, compared with 28% of patients not reporting said behavior. Eighteen percent of patients met the criteria for adult antisocial behavior. Only one patient with adult antisocial behavior was returned to full duty. Conclusions: This study found that a history of aggressive/impulsive behavior was positively correlated with substance abuse and negatively correlated with return to full military duty. C1 USN, Med Ctr, Dept Psychiat, Portsmouth, VA USA. RP Conard, R (reprint author), USN, Med Ctr, Dept Psychiat, Portsmouth, VA USA. NR 18 TC 0 Z9 1 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 SEP PY 1998 VL 163 IS 9 BP 594 EP 598 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA 116YG UT WOS:000075752200003 PM 9753983 ER PT J AU Weinstein, ML AF Weinstein, ML TI Update on wound healing: A review of the literature SO MILITARY MEDICINE LA English DT Review ID ULCERS C1 USN Hosp, Dept Phys Therapy, Camp Lejeune, NC 28547 USA. RP Weinstein, ML (reprint author), USN Hosp, Dept Phys Therapy, Camp Lejeune, NC 28547 USA. NR 15 TC 4 Z9 6 U1 1 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 SEP PY 1998 VL 163 IS 9 BP 620 EP 624 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA 116YG UT WOS:000075752200008 PM 9753988 ER PT J AU Lee, RL AF Lee, RL TI The hidden cost of tobacco smoke SO MILITARY MEDICINE LA English DT Letter C1 USN, Med Corps, Dept Pediat, Med Ctr, Portsmouth, VA USA. RP Lee, RL (reprint author), USN, Med Corps, Dept Pediat, Med Ctr, Portsmouth, VA USA. NR 0 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 SEP PY 1998 VL 163 IS 9 BP 624 EP 624 PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA 116YG UT WOS:000075752200009 PM 9753989 ER PT J AU Abraham, FF Brodbeck, D Rudge, WE Broughton, JQ Schneider, D Land, B Lifka, D Gerner, J Rosenkrantz, M Skovira, J Gao, H AF Abraham, FF Brodbeck, D Rudge, WE Broughton, JQ Schneider, D Land, B Lifka, D Gerner, J Rosenkrantz, M Skovira, J Gao, H TI Ab initio dynamics of rapid fracture SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article; Proceedings Paper CT International Conference on Computational Physics CY AUG 25-28, 1997 CL UNIV CA, SANTA CRUZ, SANTA CRUZ, CALIFORNIA SP Amer Phys Soc, Div Computat Phys & Forum Ind & Appl Phys, Int Union Pure & Appl Phys, European Phys Soc HO UNIV CA, SANTA CRUZ ID MOLECULAR-DYNAMICS; INSTABILITY DYNAMICS; BRITTLE; CRACKS; SIMULATION; MECHANICS; COMPUTER AB As our title implies, we consider materials failure at the fundamental level of atomic bond breaking and motion. Using computational molecular dynamics, scalable parallel computers and visualization, we are studying the failure of notched solids under tension using in excess of 10(8) atoms. In rapid brittle fracture, two of the most intriguing features are the roughening of a crack's surface with increasing speed and the terminal crack speed which is much less than the theoretical prediction. Our two-dimensional simulations show conclusively that a dynamic instability of the crack motion occurs as it approaches one-third of the surface sound speed. This discovery provides an explanation for the crack's surface roughening and limiting speed. For three-dimensional slabs, we find that an intrinsically ductile FCC crystal can experience brittle failure for certain crack orientations. A dynamic instability also occurs, but brittle failure is not maintained. The instability is immediately followed by a brittle-to-ductile transition and plasticity. Hyperelasticity, or the elasticity near failure, governs many of the failure processes observed in our simulations and its many roles are elucidated. C1 IBM Corp, Almaden Res Ctr, Div Res, San Jose, CA 95120 USA. USN, Res Lab, Washington, DC 20375 USA. Cornell Univ, Cornell Theory Ctr, Ithaca, NY 14853 USA. Stanford Univ, Div Mech & Computat, Stanford, CA 94305 USA. RP Abraham, FF (reprint author), IBM Corp, Almaden Res Ctr, Div Res, San Jose, CA 95120 USA. RI Gao, Huajian/F-9360-2010; Schneider, David/H-2236-2012 OI Schneider, David/0000-0002-2124-8385 NR 25 TC 24 Z9 24 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD SEP PY 1998 VL 6 IS 5 BP 639 EP 670 DI 10.1088/0965-0393/6/5/010 PG 32 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 136EB UT WOS:000076844600010 ER PT J AU Knutson, EM AF Knutson, EM TI The rhythm of French: French pronunciation tutor for English speakers. SO MODERN LANGUAGE JOURNAL LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Knutson, EM (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV WISCONSIN PRESS PI MADISON PA JOURNAL DIVISION, 2537 DANIELS ST, MADISON, WI 53718 USA SN 0026-7902 J9 MOD LANG J JI Mod. Lang. J. PD FAL PY 1998 VL 82 IS 3 BP 434 EP 434 DI 10.2307/329980 PG 1 WC Education & Educational Research; Linguistics SC Education & Educational Research; Linguistics GA 125NP UT WOS:000076243900023 ER PT J AU Ralph, FM Armi, L Bane, JM Dorman, C Neff, WD Neiman, PJ Nuss, W Persson, POG AF Ralph, FM Armi, L Bane, JM Dorman, C Neff, WD Neiman, PJ Nuss, W Persson, POG TI Observations and analysis of the 10-11 June 1994 coastally trapped disturbance SO MONTHLY WEATHER REVIEW LA English DT Article ID STATES WEST-COAST; KELVIN WAVES; NORTHERN CALIFORNIA; MESOSCALE RIDGES; LOWER ATMOSPHERE; WIND REVERSALS; MARINE-LAYER; POTENTIAL VORTICITY; BOUNDARY-LAYER; CATALINA EDDY AB A coastally trapped disturbance (CTD), characterized by southerly flow at the surface on 10-11 June 1994, was observed from the California Eight to Bodega Bay during a field experiment along the California coast. (North-south approximates the coast-parallel direction.) Data from a special observational network of wind profilers, radio acoustic sounding systems, special surface data, balloon ascents, and a research aircraft were used with satellite and synoptic data to explore both the CTD structure and the regional-scale changes before the event. The disruption of the climatological northerly flow along the central California coast, which preconditioned the area for the development of a CTD, began with the eastward movement of a surface high into Washington and Oregon and the amplification of a thermal low in northern California. As with most CTDs in the region, this occurred over the 2-3 days preceding the CTD's initiation. These large-scale changes caused westward advection of warm continental air across much of the California coast, which increased temperatures by 10 degrees-12 degrees C in the layer from 0.4 to 2.0 km above mean sea level (MSL) during the 48 h before southerly how appeared offshore at the surface. The warming reversed the alongshore sea level pressure gradients near the coast by creating a region of pressure falls extending along 600-1000 km of the coast. This also modified the cross-shore pressure gradient and thus the geostrophic alongshore flow. The warming along the coast also increased the strength of the temperature inversion capping the marine boundary layer (MBL) by a factor of 2-4 over 48 h. The synoptic-scale changes also moved the axis of the climatological near-surface, northerly jet much farther offshore from central California and strengthened this jet near the headlands of Gapes Mendocino and Blanco. The development and decay of southerly flow at the surface along the coast coincided roughly with the evolution of a mesoscale low 200 km offshore, and of a coastal ridge roughly 100 km wide. However, the CTD initiation also followed a 500-m thickening of the MBL inversion in the California Eight region where a Catalina eddy was initially present. At surface sites, the CTD was marked by the passage of a pressure trough, followed by a gradual shift to southerly flow and the appearance of clouds. The area of low cloud was not coincident with the region of southerly flow. The transition to southerly flow propagated northward along shore at 11.9 +/- 0.3 m s(-1) on 10 June, stalled for 11-12 h during the part of the diurnal cycle normally characterized by enhanced northerly flow, and then continued propagating northward along shore at 11.6 m s(-1). Both the geostrophic wind and the isallobaric component of the ageostrophic wind were consistent with southerly how at the surface. Southerly flow was observed up to 5 km MSL in this event and in others, which indicates that the synoptic-scale environment of many CTDs in this region may include a deep tropospheric cyclonic circulation or trough offshore. Both cross-shore and alongshore flights performed by a research aircraft documented the CTD structure and showed that the southerly flow extended at least 100 km offshore and appeared first within the MBL inversion as the inversion thickened upward. While the top of the inversion rose, the height of the inversion's base remained almost unchanged. The thickening of the inversion decreased with distance offshore, and there was no significant change in the MBL depth (i.e., the inversion base height), until 12-14 h after the surface wind shift. Thus, it is suggested that two-layer, shallow water idealizations may be unable to represent this phenomenon adequately. Nonetheless. the gradual wind shift, the thickening inversion, and the correlation between southerly flow and a mesoscale coastal pressure ridge are consistent with a coastally trapped Kelvin wave, albeit one with a higher-order vertical structure that can exist in a two-layer model. However. the semipermanent nature of the changes in the MBL and its inversion is more characteristic of a shallowly sloped internal bore. The temperature increase and lack of southerly flow exceeding the northward phase speed are inconsistent with gravity current behavior. C1 NOAA, ERL, Environm Technol Lab, Boulder, CO 80303 USA. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. Univ N Carolina, Marine Sci Program, Chapel Hill, NC USA. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. RP Ralph, FM (reprint author), NOAA, ERL, Environm Technol Lab, Mail Code R-E-ET7,325 Broadway, Boulder, CO 80303 USA. RI Neff, William/E-2725-2010 OI Neff, William/0000-0003-4047-7076 NR 50 TC 34 Z9 35 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 SEP PY 1998 VL 126 IS 9 BP 2435 EP 2465 DI 10.1175/1520-0493(1998)126<2435:OAAOTJ>2.0.CO;2 PG 31 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 114VE UT WOS:000075629200008 ER PT J AU Morgan, WB Lin, WC AF Morgan, WB Lin, WC TI Predicting ship hydrodynamic performance in today's world SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The current status of ship hydrodynamic performance predictions is reviewed in light of available techniques for both scale-model experiments and computations. Possibilities of more efficient and preferable procedures for performing model basin tasks through strategic integration of various theoretical/computational and experimental methods are discussed with a perspective toward future development. C1 USN, Ctr Surface Warfare, Carderock Div, Silver Spring, MD 20910 USA. RP Morgan, WB (reprint author), USN, Ctr Surface Warfare, Carderock Div, Silver Spring, MD 20910 USA. NR 47 TC 2 Z9 2 U1 0 U2 0 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 SEP PY 1998 VL 110 IS 5 BP 91 EP 98 PG 8 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA 147YH UT WOS:000077525100007 ER PT J AU Apte, A Jayasuriya, A Kennington, J Krass, I Mohamed, R Sorensen, S Whitler, J AF Apte, A Jayasuriya, A Kennington, J Krass, I Mohamed, R Sorensen, S Whitler, J TI Class scheduling algorithms for Navy training schools SO NAVAL RESEARCH LOGISTICS LA English DT Article ID TRAVELING SALESMAN PROBLEM; OPTIMIZATION AB The problem of developing good schedules for Navy C-Schools has been modeled as a combinatorial optimization problem. The only complicating feature of the problem is that classes must be grouped together into sequences known as pipelines. An ideal schedule will have all classes in a pipeline scheduled in consecutive weeks. The objective is to eliminate the nonproductive time spent by sailors at C-Schools who are waiting for the next class in a pipeline. In this investigation an implicit enumeration procedure for this problem was developed. The key component of our algorithm is a specialized greedy algorithm which is used to obtain a good initial incumbent. Often this initial incumbent is either an optimal schedule or a near optimal schedule. In an empirical analysis with the only other competing software system, our greedy heuristic found equivalent or better solutions in substantially less computer time. This greedy heuristic was extended and modified for the A-School scheduling problem and aias found to be superior to its only competitor. (C) 1998 John Wiley & Sons, Inc. C1 So Methodist Univ, Dept Comp Sci & Engn, Dallas, TX 75275 USA. Defense Manpower Data Ctr, Monterey, CA 93490 USA. Cairo Univ, Cairo, Egypt. USN, Ctr Personnel Res & Dev, San Diego, CA 92152 USA. RP Kennington, J (reprint author), So Methodist Univ, Dept Comp Sci & Engn, Dallas, TX 75275 USA. NR 18 TC 3 Z9 3 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0894-069X J9 NAV RES LOG JI Nav. Res. Logist. PD SEP PY 1998 VL 45 IS 6 BP 533 EP 551 DI 10.1002/(SICI)1520-6750(199809)45:6<533::AID-NAV1>3.0.CO;2-3 PG 19 WC Operations Research & Management Science SC Operations Research & Management Science GA 111GA UT WOS:000075427900001 ER PT J AU Kang, JU Posey, R AF Kang, JU Posey, R TI Demonstration of supercontinuum generation in a long-cavity fiber ring laser SO OPTICS LETTERS LA English DT Article AB We demonstrate generation of supercontinuum pulses directly from a passively mode-locked long-cavity fiber ring laser. The laser output exhibited a blueshifted spectrum extending from 1350 to 1550 nm with an average output power greater than 60 mW. (C) 1998 Optical Society of America. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kang, JU (reprint author), USN, Res Lab, Code 5670, Washington, DC 20375 USA. RI Kang, Jin/A-3228-2010 NR 9 TC 13 Z9 14 U1 0 U2 3 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 SEP 1 PY 1998 VL 23 IS 17 BP 1375 EP 1377 DI 10.1364/OL.23.001375 PG 3 WC Optics SC Optics GA 115ZX UT WOS:000075697400016 PM 18091790 ER PT J AU Barrett, FJ Peplowski, K AF Barrett, FJ Peplowski, K TI Minimal structures within a song: An analysis of "All of me" SO ORGANIZATION SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Jazz as a Metaphor for Organizing in the 21st Century at the 1995 Academy-of-Management National Conference CY 1995 CL VANCOUVER, CANADA SP Acad Management C1 USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93941 USA. RP Barrett, FJ (reprint author), USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93941 USA. NR 0 TC 14 Z9 14 U1 0 U2 4 PU INST OPERATIONS RESEARCH MANAGEMENT SCIENCES PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2909 USA SN 1047-7039 J9 ORGAN SCI JI Organ Sci. PD SEP-OCT PY 1998 VL 9 IS 5 BP 558 EP 560 DI 10.1287/orsc.9.5.558 PG 3 WC Management SC Business & Economics GA 133BF UT WOS:000076666000005 ER PT J AU Barrett, FJ AF Barrett, FJ TI Creativity and improvisation in jazz and organizations: Implications for organizational learning SO ORGANIZATION SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Jazz as a Metaphor for Organizing in the 21st Century at the 1995 Academy-of-Management National Conference CY 1995 CL VANCOUVER, CANADA SP Acad Management C1 USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93943 USA. RP Barrett, FJ (reprint author), USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93943 USA. NR 63 TC 156 Z9 158 U1 4 U2 54 PU INST OPERATIONS RESEARCH MANAGEMENT SCIENCES PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2909 USA SN 1047-7039 J9 ORGAN SCI JI Organ Sci. PD SEP-OCT PY 1998 VL 9 IS 5 BP 605 EP 622 DI 10.1287/orsc.9.5.605 PG 18 WC Management SC Business & Economics GA 133BF UT WOS:000076666000014 ER PT J AU Girgis, N Sultan, Y Frenck, RW El-Gendy, A Farid, Z Mateczun, A AF Girgis, N Sultan, Y Frenck, RW El-Gendy, A Farid, Z Mateczun, A TI Azithromycin compared with rifampin for eradication of nasopharyngeal colonization by Neisseria meningitidis SO PEDIATRIC INFECTIOUS DISEASE JOURNAL LA English DT Article DE azithromycin; rifampin; Neisseria meningitidis ID CIPROFLOXACIN AB Objectives. To evaluate the efficacy and safety of azithromycin compared with rifampin for eradication of nasopharyngeal carriage of Neisseria meningitidis Methods. Pharyngeal swabs were obtained from 500 students attending nursing school in Cairo, Egypt, to determine the colonization rate with N. meningitidis. Colonized individuals were randomized to receive azithromycin (500 mg once) or rifampin (600 mg twice daily for four doses). Subjects were then recultured 1 and 2 weeks posttreatment to determine the effectiveness of the antibiotic therapy for eradication of meningococcal nasopharyngeal colonization. Results, Individuals treated with azithromycin had a 93% eradication rate at 1 and 2 weeks posttreatment comparable with 95 and 91%, respectively, for rifampin. No significant side effects were reported by any subjects treated with either antibiotic. Conclusion. Azithromycin is effective in the eradication of N, meningitidis from the nasopharynx of asymptomatic colonized individuals and deserves further evaluation for use as prophylaxis against N, meningitidis. C1 USN, Med Res Unit 3, Clin Invest Branch, FPO, AE 09835 USA. Abbassia Fever Hosp, Cairo, Egypt. RP Girgis, N (reprint author), USN, Med Res Unit 3, Clin Invest Branch, PSC 452,Box 5000, FPO, AE 09835 USA. NR 19 TC 37 Z9 39 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0891-3668 J9 PEDIATR INFECT DIS J JI Pediatr. Infect. Dis. J. PD SEP PY 1998 VL 17 IS 9 BP 816 EP 819 DI 10.1097/00006454-199809000-00013 PG 4 WC Immunology; Infectious Diseases; Pediatrics SC Immunology; Infectious Diseases; Pediatrics GA 126ER UT WOS:000076280400010 PM 9779768 ER PT J AU Clapp, CR Wheeler, DS Ponaman, ML McEachren, H Poss, WB AF Clapp, CR Wheeler, DS Ponaman, ML McEachren, H Poss, WB TI Isoflurane therapy for status asthmaticus in children. SO PEDIATRICS LA English DT Meeting Abstract C1 USN, Med Ctr, Dept Pediat, San Diego, CA 92152 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ACAD PEDIATRICS PI ELK GROVE VILLAGE PA 141 NORTH-WEST POINT BLVD,, ELK GROVE VILLAGE, IL 60007-1098 USA SN 0031-4005 J9 PEDIATRICS JI Pediatrics PD SEP PY 1998 VL 102 IS 3 SU 1 BP 705 EP 705 PG 1 WC Pediatrics SC Pediatrics GA 117YM UT WOS:000075810500078 ER PT J AU Brown, CVR Canty, TG Canty, TG AF Brown, CVR Canty, TG Canty, TG TI Injury of the GI tract from child abuse SO PEDIATRICS LA English DT Meeting Abstract C1 Univ Washington, Seattle, WA 98195 USA. Childrens Hosp, San Diego, CA USA. USN, Ctr Med, San Diego, CA 92152 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER ACAD PEDIATRICS PI ELK GROVE VILLAGE PA 141 NORTH-WEST POINT BLVD,, ELK GROVE VILLAGE, IL 60007-1098 USA SN 0031-4005 J9 PEDIATRICS JI Pediatrics PD SEP PY 1998 VL 102 IS 3 SU 1 BP 803 EP 803 PG 1 WC Pediatrics SC Pediatrics GA 117YM UT WOS:000075810500309 ER PT J AU Poss, WB Fazio, RF Wheeler, DS AF Poss, WB Fazio, RF Wheeler, DS TI Resident training in pediatric critical care transport medicine. SO PEDIATRICS LA English DT Meeting Abstract C1 USN, Med Ctr, Dept Pediat, San Diego, CA 92152 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ACAD PEDIATRICS PI ELK GROVE VILLAGE PA 141 NORTH-WEST POINT BLVD,, ELK GROVE VILLAGE, IL 60007-1098 USA SN 0031-4005 J9 PEDIATRICS JI Pediatrics PD SEP PY 1998 VL 102 IS 3 SU 1 BP 817 EP 817 PG 1 WC Pediatrics SC Pediatrics GA 117YM UT WOS:000075810500350 ER PT J AU Chien, CH Blaisten-Barojas, E Pederson, MR AF Chien, CH Blaisten-Barojas, E Pederson, MR TI Magnetic and electronic properties of rhodium clusters SO PHYSICAL REVIEW A LA English DT Article ID GENERALIZED GRADIENT APPROXIMATION; DENSITY-FUNCTIONAL THEORY; METAL-CLUSTERS; STATES; DIMERS; RH; SURFACES; 1ST AB We have used all-electron local (LDA) and nonlocal (GGA) approximations to the density-functional theory to determine binding energies, equilibrium geometries, vibrational frequencies, and magnetic properties of Rh, clusters (N less than or equal to 6). We present careful tests on the Rh-2 dimer that compare results as calculated with a large (18-single Gaussian) and a very large (23-single Gaussian) basis sets. While the smaller set of Gaussians leads to underconverged results, we find that the large basis set leads to converged results that are also in excellent agreement with the experimental data available for Rh,. The ground state of Ph-2 is confirmed to be a quintuplet, the trigonal Rh-2 is predicted to be a sextuplet, Ri(4) in its tetrahedral configuration is a singlet, Rh-5 sextuplet is a square pyramid, and Rh-6 septuplet is the octahedron. Results from several excited states are calculated and presented as well. It is found that LDA overestimates the binding energy but that GGA corrects this deficiency and predicts longer bond lengths. C1 George Mason Univ, Inst Computat Sci & Informat, Fairfax, VA 22030 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Chien, CH (reprint author), George Mason Univ, Inst Computat Sci & Informat, Fairfax, VA 22030 USA. EM eblaiste@gmu.edu RI Blaisten-Barojas, Estela/B-9520-2009 NR 27 TC 63 Z9 64 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 1998 VL 58 IS 3 BP 2196 EP 2202 DI 10.1103/PhysRevA.58.2196 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 116MY UT WOS:000075730200072 ER PT J AU Kirkpatrick, SM Yang, HS Dennis, WM AF Kirkpatrick, SM Yang, HS Dennis, WM TI Picosecond acoustic phonon dynamics in LaF3 : Pr3+ SO PHYSICAL REVIEW B LA English DT Article ID NONEQUILIBRIUM PHONONS; GENERATION; RADIATION AB A plasma switching technique is used to generate subnanosecond, far-infrared (FIR) pulses with frequency 113 cm(-1). The generation of subnanosecond FIR pulses enables us to improve the time resolution of phonon spectroscopic measurements from 50 ns to 350 ps. As an application of this technique, we investigate the subnanosecond dynamics of high-frequency phonons in 0.5% LaF3:Pr3+. In particular, we report on the generation and detection of a subnanosecond nonequilibrium phonon population at 113 cm(-1), and the temporal evolution of the resulting decay products. The frequency dependence of the phonon relaxation rates of acoustic phonons in this material is found to deviate from the omega(5) frequency dependence predicted by an isotropic model with linear dispersion. A more realistic model based on the actual dispersion curves of the material is presented and compared with the data. C1 Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. RP Kirkpatrick, SM (reprint author), USN, Res Lab, Laser Phys Branch, Code 5640, Washington, DC 20375 USA. NR 16 TC 2 Z9 2 U1 1 U2 1 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 1 PY 1998 VL 58 IS 9 BP 5417 EP 5422 DI 10.1103/PhysRevB.58.5417 PG 6 WC Physics, Condensed Matter SC Physics GA 116JA UT WOS:000075720100049 ER PT J AU Pederson, MR Reuse, F Khanna, SN AF Pederson, MR Reuse, F Khanna, SN TI Magnetic transition in Mn-n (n=2-8) clusters SO PHYSICAL REVIEW B LA English DT Article ID GENERALIZED GRADIENT APPROXIMATION; LOCAL-SPIN-DENSITY; RESONANCE; GAS AB Theoretical electronic structure studies on Mn-n (n = 2-8) clusters have been carried out using a linear-combination-of-atomic-orbitals-molecular-orbital approach within the density-functional formalism. It is shown that Mn-2 and Mn-3 have energetically close ferromagnetic and antiferromagnetic or frustrated antiferromagnetic solutions. Mn-4, Mn-5, Mn-6, Mn-7, and Mn-8 are all ferromagnetic with moments of 20, 23, 26, 29, and 32 mu(B). The appearance of ferromagnetic character is shown to be accompanied by bending between minority d states; The relation between geometry and multiplicity and the possibility of closely spaced multiplet states are discussed. C1 USN, Res Lab, Complex Syst Theory Branch 6692, Washington, DC 20375 USA. Ecole Polytech Fed Lausanne, Inst Phys Expt, PHB Ecublens, CH-1015 Lausanne, Switzerland. Virginia Commonwealth Univ, Dept Phys, Richmond, VA 23284 USA. RP USN, Res Lab, Complex Syst Theory Branch 6692, Washington, DC 20375 USA. NR 26 TC 119 Z9 120 U1 1 U2 5 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 1 PY 1998 VL 58 IS 9 BP 5632 EP 5636 DI 10.1103/PhysRevB.58.5632 PG 5 WC Physics, Condensed Matter SC Physics GA 116JA UT WOS:000075720100076 ER PT J AU Rudd, RE Broughton, JQ AF Rudd, RE Broughton, JQ TI Coarse-grained molecular dynamics and the atomic limit of finite elements SO PHYSICAL REVIEW B LA English DT Article ID SIMULATION AB We develop a technique for simulation of the mechanics of micron-scale solid systems: coarse-grained molecular dynamics (CGMD). It captures the important atomistic effects without the computational cost of conventional molecular dynamics (MD). The CGMD equations of motion are derived directly from finite temperature MD through a statistical coarse graining procedure. so they agree with MD as the mesh size is reduced to the atomic scale. This allows a seamless coupling of length scales. The use of efficient CGMD in peripheral regions extends atomistic simulation to much larger systems than amenable to MD alone. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Rudd, RE (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. EM rudd@dave.nrl.navy.mil; broughto@dave.nrl.navy.mil OI Rudd, Robert/0000-0002-6632-2681 NR 9 TC 159 Z9 164 U1 4 U2 27 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 1 PY 1998 VL 58 IS 10 BP R5893 EP R5896 DI 10.1103/PhysRevB.58.R5893 PG 4 WC Physics, Condensed Matter SC Physics GA 121HN UT WOS:000076007600002 ER PT J AU Krushelnick, K Moore, CI Ting, A Burris, HR AF Krushelnick, K Moore, CI Ting, A Burris, HR TI Frequency mixing of high intensity laser light with stimulated Raman backscattered radiation in underdense plasmas SO PHYSICAL REVIEW E LA English DT Article ID 2ND-HARMONIC GENERATION; EMISSION; FILAMENTATION; SCATTERING; PULSE AB Sidescattered radiation from the interaction of an ultraintense laser pulse (P>2 TW) with underdense helium plasmas (n(e)approximate to 10(19) cm(-3)) is measured and emission at 90 degrees from the axis of laser propagation is observed to be broadened significantly near the second harmonic (Delta lambda=30-40 nm). This result is consistent with sum frequency mixing of forward propagating laser light and the broadened backscattered stimulated Raman scattered radiation that occurs within transient filamentary structures produced by the ponderomotive force of the focused laser pulse. C1 Cornell Univ, Plasma Studies Lab, Ithaca, NY 14853 USA. Omega P Inc, New Haven, CT 06520 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Krushelnick, K (reprint author), Cornell Univ, Plasma Studies Lab, Ithaca, NY 14853 USA. NR 15 TC 3 Z9 3 U1 0 U2 2 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 SEP PY 1998 VL 58 IS 3 BP 4030 EP 4032 DI 10.1103/PhysRevE.58.4030 PN B PG 3 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 121HM UT WOS:000076007400094 ER PT J AU Smith, GB Leighton, RI Tang, ST AF Smith, GB Leighton, RI Tang, ST TI Turbulent transition in the infrared SO PHYSICS OF FLUIDS LA English DT Article; Proceedings Paper CT 15th Annual Fluid Mechanics Photo Contest at the Meeting of the American-Physical-Society-Division-of-Fluid-Dynamics CY NOV, 1997 CL SAN FRANCISCO, CALIFORNIA SP Amer Phys Soc, Div Fluid Dynam C1 USN, Res Lab, Washington, DC 20375 USA. Univ Delaware, Newark, DE 19716 USA. RP Smith, GB (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD SEP PY 1998 VL 10 IS 9 BP S9 EP S9 PG 1 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 114JA UT WOS:000075604300009 ER PT J AU Velikovich, AL Cochran, FL Davis, J Chong, YK AF Velikovich, AL Cochran, FL Davis, J Chong, YK TI Stabilized radiative Z-pinch loads with tailored density profiles SO PHYSICS OF PLASMAS LA English DT Article ID RAYLEIGH-TAYLOR INSTABILITY; RICHTMYER-MESHKOV INSTABILITY; SUPPRESSION; CURVATURE; FRONTS; GROWTH; WAVES; GAS AB Mitigation of the Rayleigh-Taylor (RT) instability of Z-pinch;loads imploded from large initial radii through tailoring initial load density profiles in radial and axial directions is studied numerically. These methods could be helpful for a variety of applications of high-power Z-pinches, from producing large amounts of K-shell radiation to imploding inertial confinement fusion pellets. Radial density tailoring is demonstrated to delay the onset of the RT instability development at the expense of reducing the energy available for conversion into radiation. Axial density tailoring can fully stabilize acceleration of a fraction of the initial load mass. For a better tradeoff between stability and radiative performance of the loads, the density profiles could be tailored in two dimensions, combining the advantages of both methods. Post-processing of the radiation-magnetohydrodynamic simulation results demonstrates that an appreciable K-shell argon radiation power could be generated with a stabilized argon load imploded by a 5 MA current from a similar to 10 cm initial radius in about 0.5 mu s. (C) 1998 American Institute of Physics. [S1070-664X(98)03809-9] C1 Berkeley Res Assoc Inc, Springfield, VA 22150 USA. USN, Res Lab, Div Plasma Phys, Radiat Hydrodynam Branch, Washington, DC 20375 USA. RP Velikovich, AL (reprint author), Berkeley Res Assoc Inc, Springfield, VA 22150 USA. RI Velikovich, Alexander/B-1113-2009 NR 49 TC 28 Z9 29 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 SEP PY 1998 VL 5 IS 9 BP 3377 EP 3388 DI 10.1063/1.873063 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 117KR UT WOS:000075780900035 ER PT J AU Murrell, GL Karakla, DW Messa, A AF Murrell, GL Karakla, DW Messa, A TI Free flap repair of septal perforation SO PLASTIC AND RECONSTRUCTIVE SURGERY LA English DT Article; Proceedings Paper CT Autumn Meeting of the Academy-of-Facial-Plastic-and-Reconstructive-Surgery CY SEP 04-05, 1997 CL SAN FRANCISCO, CALIFORNIA SP Acad Facial Plast & Reconstruct Surg ID LARGE NASOSEPTAL PERFORATIONS; FOREARM FLAP; CLOSURE C1 Natl Naval Med Ctr, Dept Otolaryngol Head & Neck Surg, Portsmouth, VA 23708 USA. Natl Naval Med Ctr, Dept Plast Surg, Portsmouth, VA 23708 USA. RP Murrell, GL (reprint author), Natl Naval Med Ctr, Dept Otolaryngol Head & Neck Surg, Portsmouth Code 0609, Portsmouth, VA 23708 USA. NR 16 TC 11 Z9 11 U1 0 U2 1 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 SEP PY 1998 VL 102 IS 3 BP 818 EP 821 DI 10.1097/00006534-199809030-00029 PG 4 WC Surgery SC Surgery GA 114JM UT WOS:000075605400029 PM 9727449 ER PT J AU Murphey, MD Flemming, DJ Boyea, SR Bojescul, JA Sweet, DE Temple, HT AF Murphey, MD Flemming, DJ Boyea, SR Bojescul, JA Sweet, DE Temple, HT TI Enchondroma versus chondrosarcoma in the appendicular skeleton: Differentiating features SO RADIOGRAPHICS LA English DT Article DE bone neoplasms; bone neoplasms, diagnosis; enchondroma; sarcoma ID MALIGNANT CARTILAGE TUMORS; BONE-LESIONS; MR; RADIOLOGY; BIOLOGY; GRADE; RADIOGRAPHY; APPEARANCE; PATHOLOGY; DIAGNOSIS AB Distinction of enchondroma versus intramedullary chondrosarcoma affecting the appendicular skeleton (proximal to the metacarpals and metatarsals) is a frequent diagnostic dilemma, The authors studied a large series of patients with these lesions (92 with enchondromas, 95 with chondrosarcomas) using statistical assessment of both clinical parameters and numerous radiologic manifestations on images from multiple modalities to identify differentiating features. Multiple clinical and imaging parameters demonstrated statistically significant differences between enchondroma and chondrosarcoma, particularly pain related to the lesion, deep endosteal scalloping (greater than two-thirds of cortical thickness), cortical destruction and soft-tissue mass (at computed tomography or magnetic resonance imaging), periosteal reaction (at radiography), and marked uptake of radionuclide (greater than the anterior iliac crest) at bone scintigraphy, All of these features strongly suggested the diagnosis of chondrosarcoma, These criteria allow distinction of appendicular enchondroma and chondrosarcoma in at least 90% of cases. C1 Armed Forces Inst Pathol, Dept Radiol Pathol, Washington, DC 20306 USA. Armed Forces Inst Pathol, Dept Orthoped Pathol, Washington, DC 20306 USA. Uniformed Serv Univ Hlth Sci, Dept Radiol & Nucl Med, Bethesda, MD 20814 USA. Uniformed Serv Univ Hlth Sci, Dept Surg, Bethesda, MD 20814 USA. Univ Maryland, Sch Med, Dept Radiol, Baltimore, MD 21201 USA. USN, Natl Med Ctr, Dept Radiol, Bethesda, MD USA. Walter Reed Army Med Ctr, Dept Orthoped Surg, Washington, DC 20307 USA. RP Murphey, MD (reprint author), Armed Forces Inst Pathol, Dept Radiol Pathol, Bldg 54,Rm M-121,16th & Alaska Sts NW, Washington, DC 20306 USA. NR 45 TC 111 Z9 126 U1 1 U2 7 PU RADIOLOGICAL SOC NORTH AMER PI EASTON PA 20TH AND NORTHAMPTON STS, EASTON, PA 18042 USA SN 0271-5333 J9 RADIOGRAPHICS JI Radiographics PD SEP-OCT PY 1998 VL 18 IS 5 BP 1213 EP 1237 PG 25 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 117BJ UT WOS:000075759800017 PM 9747616 ER PT J AU Wilcox, JR AF Wilcox, JR TI The meaning of words SO RADIOLOGY LA English DT Letter C1 USN, Med Ctr, Dept Radiol, Portsmouth, VA 23708 USA. RP Wilcox, JR (reprint author), USN, Med Ctr, Dept Radiol, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU RADIOLOGICAL SOC NORTH AMER PI EASTON PA 20TH AND NORTHAMPTON STS, EASTON, PA 18042 USA SN 0033-8419 J9 RADIOLOGY JI Radiology PD SEP PY 1998 VL 208 IS 3 BP 829 EP 829 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 112HN UT WOS:000075488200042 PM 9722867 ER PT J AU Sandidge, JC Holyer, RJ AF Sandidge, JC Holyer, RJ TI Coastal bathymetry from hyperspectral observations of water radiance SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID AVIRIS; IMAGERY AB Water depth, bottom reflectance, inherent optical properties of the water column (scattering, absorption, and fluorescence), and illumination conditions combine to determine the upwelling spectral radiance of coastal waters. If these complex optical relationships could be quantified, it would be possible to extract coastal information from spectral radiance data. We use data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) in a neural network system to establish quantitative, empirical relationships between one of these parameters, depth, and remotely sensed spectral radiance. Data are analyzed for two areas: the western coast of Florida in the Tampa Bay area and the Florida Keys between Upper Matecumbe and Plantation Keys. The neural network approach results in retrieval of reasonable depths from spectral radiance in both cases over a depth range of 0 to 6 m. Retrieved depths for Tampa Bay are accurate to a RMS error of 0.84 m relative to depths in the National Ocean Survey (NOS) Hydrographic Database, and the Keys retrievals have an RMS error of 0.39 m relative to a bathymetric survey conducted to support this study. A neural network trained on a combination of the two data sets results in a combined RMS error of 0.48 m, nearly the same performance as neural networks trained individually. The ability of the neural network to generalize, producing algorithms with some degree of universality among diverse coastal environments is, thereby, demonstrated. The result of the generalization analysis is of practical importance because it indicates that the neural network may not require an extensive training set of water depth data in order to the "tuned" for each location where depth retrievals are desired. While empirical the neural network is in some sense a model of the inversion of the radiative transfer problem within the marine environment. The neural network approach, therefore, operates on a higher level than more traditional statistical curve fitting solutions for retrieval of remotely sensed information. Published by Elsevier Science Inc. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Sandidge, JC (reprint author), USN, Res Lab, Code 7340,Bldg 1105,Rm F605G, Stennis Space Ctr, MS 39529 USA. NR 17 TC 59 Z9 71 U1 2 U2 8 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD SEP PY 1998 VL 65 IS 3 BP 341 EP 352 DI 10.1016/S0034-4257(98)00043-1 PG 12 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 112ZL UT WOS:000075524700010 ER PT J AU Hisnanick, JJ AF Hisnanick, JJ TI Social policies for children. SO REVIEW OF SOCIAL ECONOMY LA English DT Book Review C1 Childrens Natl Med Ctr, Washington, DC 20010 USA. USN Acad, Annapolis, MD 21402 USA. RP Hisnanick, JJ (reprint author), Childrens Natl Med Ctr, Washington, DC 20010 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ROUTLEDGE PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0034-6764 J9 REV SOC ECON JI Rev. Soc. Econ. PD FAL PY 1998 VL 56 IS 3 BP 386 EP 389 PG 4 WC Economics SC Business & Economics GA 126YH UT WOS:000076322600013 ER PT J AU Smith, G Volpano, D AF Smith, G Volpano, D TI A sound polymorphic type system for a dialect of C SO SCIENCE OF COMPUTER PROGRAMMING LA English DT Article; Proceedings Paper CT 6th European Symposium on Programming (ESOP 96) CY APR 22-26, 1996 CL LINKOPING, SWEDEN DE C; type systems; polymorphism; variables; pointers; type soundness; natural semantics; transition semantics ID REFERENCES; VARIABLES AB Advanced polymorphic type systems have come to play an important role in the world of functional programming. But, so far, these type systems have had little impact upon widely used imperative programming languages like C and C++. We show that ML-style polymorphism can be integrated smoothly into a dialect of C, which we call Polymorphic C. It has the same pointer operations as C, including the address-of operator &, the dereferencing operator *, and pointer arithmetic. We give a natural semantics for Polymorphic C, and prove a type soundness theorem that gives a rigorous and useful characterization of what can go wrong when a well-typed Polymorphic C program is executed. For example, a well-typed Polymorphic C program may fail to terminate, or it may abort due to a dangling pointer error. Proving such a type soundness theorem requires a notion of an attempted program execution; we show that a natural semantics gives rise quite naturally to a transition semantics, which we call a natural transition semantics, that models program execution in terms of transformations of partial derivation trees. This technique should be generally useful in proving type soundness theorems for languages defined using natural semantics. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Florida Int Univ, Sch Comp Sci, Miami, FL 33199 USA. USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. RP Smith, G (reprint author), Florida Int Univ, Sch Comp Sci, Miami, FL 33199 USA. NR 24 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6423 J9 SCI COMPUT PROGRAM JI Sci. Comput. Program. PD SEP PY 1998 VL 32 IS 1-3 BP 49 EP 72 DI 10.1016/S0167-6423(97)00030-0 PG 24 WC Computer Science, Software Engineering SC Computer Science GA 113KM UT WOS:000075550200003 ER PT J AU Kostoff, RN AF Kostoff, RN TI The use and misuse of citation analysis in research evaluation - Comments on theories of citation? SO SCIENTOMETRICS LA English DT Article AB The present paper addresses some of the many possible uses of citations, including bookmark, intellectual heritage, impact tracker, and self-serving purposes. The main focus is on the applicability of citation analysis as an impact or quality measure. If a paper's bibliography is viewed as consisting of a directed (research impact or quality) component related to intellectual heritage and random components related to specific self-interest topics, then for large numbers of citations from many different citing papers, the most significant intellectual heritage (research impact or quality) citations will aggregate and the random author-specific self-serving citations will be scattered and not accumulate. However, there are at least two limitations to this model of citation analysis for stand-alone use as a measure of research impact or quality. First, the reference to intellectual heritage could be positive or negative. Second, there could be systemic biases which affect the aggregate results, and one of these, the "Pied Piper Effect", is described in detail. Finally, the results of a short citation study comparing Russian and American papers in different technical fields are presented. The questions raised in interpreting this data highlight a few of the difficulties in attempting to interpret citation results without supplementary information. Leydesdorff (Leydesdorff, 1998) addresses the history of citations and citation analysis, and the transformation of a reference mechanism into a purportedly quantitative measure of research impact/quality. The present paper examines different facets of citations and citation analysis, and discusses the validity of citation analysis as a useful measure of research impact/quality. C1 Off Naval Res, Arlington, VA 22217 USA. RP Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. EM kostofr@onr.navy.mil NR 11 TC 85 Z9 87 U1 4 U2 23 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0138-9130 EI 1588-2861 J9 SCIENTOMETRICS JI Scientometrics PD SEP PY 1998 VL 43 IS 1 BP 27 EP 43 DI 10.1007/BF02458392 PG 17 WC Computer Science, Interdisciplinary Applications; Information Science & Library Science SC Computer Science; Information Science & Library Science GA 119CL UT WOS:000075877700003 ER PT J AU Arnone, RA Gould, RW AF Arnone, RA Gould, RW TI Coastal monitoring using ocean color SO SEA TECHNOLOGY LA English DT Article C1 USN, Res Lab, Ocean Color Sect, Stennis Space Ctr, MS 39529 USA. RP Arnone, RA (reprint author), USN, Res Lab, Ocean Color Sect, Stennis Space Ctr, MS 39529 USA. NR 0 TC 6 Z9 7 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 SEP PY 1998 VL 39 IS 9 BP 18 EP + PG 9 WC Engineering, Ocean SC Engineering GA 121ZK UT WOS:000076045800003 ER PT J AU Posch, TJ Puckett, ML AF Posch, TJ Puckett, ML TI Marrow MR signal abnormality associated with bilateral avulsive cortical irregularities in a gymnast SO SKELETAL RADIOLOGY LA English DT Article DE marrow; MR signal; avulsive cortical irregularity ID DISTAL FEMUR; DEFECTS AB Abnormal marrow signal and marrow enhancement have not been described in association with benign avulsive cortical irregularity. We present the case of an 11-year-old gymnast with such findings that partially resolved over time. The marrow MR abnormalities are believed to represent an extension or spectrum of findings associated with avulsive cortical irregularity, and should not instantly suggest infection or malignancy, as has been previously indicated. Careful and close clinical and radiological follow-up is required to confirm its benign course. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Radiol, San Diego, CA 92134 USA. RP Posch, TJ (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 12 TC 8 Z9 8 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0364-2348 J9 SKELETAL RADIOL JI Skeletal Radiol. PD SEP PY 1998 VL 27 IS 9 BP 511 EP 514 PG 4 WC Orthopedics; Radiology, Nuclear Medicine & Medical Imaging SC Orthopedics; Radiology, Nuclear Medicine & Medical Imaging GA 128KU UT WOS:000076405500007 PM 9809881 ER PT J AU Walters, RJ Xapsos, MA Cotal, HL Messenger, SR Summers, GP Sharps, PR Timmons, ML AF Walters, RJ Xapsos, MA Cotal, HL Messenger, SR Summers, GP Sharps, PR Timmons, ML TI Radiation response and injection annealing of P+N InGaP solar cells SO SOLID-STATE ELECTRONICS LA English DT Article ID PROTON IRRADIATION; ELECTRON; INP; RECOMBINATION; DAMAGE; DEGRADATION AB The effects of 1 MeV electron and 3 MeV proton irradiation on single-junction p(+)n InGaP solar cells are studied. The cell radiation response is monitored through measurements of current vs voltage (both in the dark and under simulated solar light (1 syn, AM0)), quantum efficiency, and capacitance vs voltage. Analysis of the data is used to determine the basic mechanisms for the cell response. High current injection causes the irradiated cells to partially recover due to a reduction in the junction dark current, which induces recovery in the cell open circuit voltage. The degradation data measured under electron and proton irradiation are correlated in terms of displacement damage dose, from which a characteristic degradation curve for this cell technology is determined. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Largo, MD 20774 USA. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. Res Triangle Inst, Res Triangle Pk, NC 27709 USA. RP Walters, RJ (reprint author), USN, Res Lab, Code 6615, Washington, DC 20375 USA. NR 23 TC 26 Z9 26 U1 0 U2 5 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 SEP PY 1998 VL 42 IS 9 BP 1747 EP 1756 DI 10.1016/S0038-1101(98)00139-7 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 123ZR UT WOS:000076156200018 ER PT J AU Chisick, MC Poindexter, FR York, AK AF Chisick, MC Poindexter, FR York, AK TI Comparing tobacco use among incoming recruits and military personnel on active duty in the United States SO TOBACCO CONTROL LA English DT Article; Proceedings Paper CT 18th Annual Scientific Session of the Society-of-Behavioral-Medicine CY APR 16-19, 1997 CL SAN FRANCISCO, CALIFORNIA SP Soc Behav Med DE tobacco use; military personnel; United States ID CIGARETTE-SMOKING AB Objective-To compare the tobacco use profile of recruits with that of military personnel on active duty to determine whether the military environment in some way induces service members to initiate tobacco use. Design and setting-Cross-sectional survey of United States armed forces active;duty and recruit personnel in 1994-95. Subjects-2711 military recruits and 4603 military personnel on active duty. Main outcome measures-Comparative cigarette smoking and smokeless tobacco use prevalence between recruits and personnel on active duty controlling for age, sex, and race. Impact of demographic factors on the odds of smoking or using smokeless tobacco. Results-Increases in tobacco use in American military personnel occurred exclusively in men. The highest tobacco use resided with white men on active duty (43% cigarette smoking; 24% smokeless tobacco use) and represents a doubling of tobacco use seen among white male recruits. Among non-white men, tobacco use increased 2-4 times between recruits and personnel on active duty. Conclusions Efforts to reduce tobacco use by American military personnel on active duty should focus more on discouraging the initiation of tobacco use. C1 USA, Ctr Hlth Promot & Prevent Med, Aberdeen Proving Ground, MD USA. USN, Res Inst Detachment, Bethesda, MD 20084 USA. RP Chisick, MC (reprint author), 2422 Bibury Lane,apartment 203, Baltimore, MD 21244 USA. NR 15 TC 30 Z9 30 U1 0 U2 1 PU BRITISH MED JOURNAL PUBL GROUP PI LONDON PA BRITISH MED ASSOC HOUSE, TAVISTOCK SQUARE, LONDON WC1H 9JR, ENGLAND SN 0964-4563 J9 TOB CONTROL JI Tob. Control PD FAL PY 1998 VL 7 IS 3 BP 236 EP 240 PG 5 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 161TR UT WOS:000078306100015 PM 9825417 ER PT J AU Chanteau, S Rabarijaona, L O'Brien, T Rahalison, L Hager, J Boisier, P Burans, J Rasolomaharo, M AF Chanteau, S Rabarijaona, L O'Brien, T Rahalison, L Hager, J Boisier, P Burans, J Rasolomaharo, M TI F1 antigenaemia in bubonic plague patients, a marker of gravity and efficacy of therapy SO TRANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE LA English DT Article DE plague; Yersina pestis ID LINKED-IMMUNOSORBENT-ASSAY; MADAGASCAR C1 Inst Pasteur, Antananarivo, Malagasy Republ. USN, Med Res Inst, Bethesda, MD 20814 USA. Naval Med Res Unit 2, Jakarta, Indonesia. Androva Hosp, Mahajanga, Malagasy Republ. RP Chanteau, S (reprint author), Inst Pasteur, POB 1274, Antananarivo, Malagasy Republ. RI BOISIER, PASCAL/A-2922-2009 NR 9 TC 19 Z9 20 U1 0 U2 1 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 SEP-OCT PY 1998 VL 92 IS 5 BP 572 EP 573 DI 10.1016/S0035-9203(98)90923-3 PG 2 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA 133LZ UT WOS:000076689200032 PM 9861385 ER PT J AU Taylor, WF Chen, S Barshtein, G Hyde, DE Yedgar, S AF Taylor, WF Chen, S Barshtein, G Hyde, DE Yedgar, S TI Enhanced aggregability of human red blood cells by diving SO UNDERSEA & HYPERBARIC MEDICINE LA English DT Article DE hyperbaria; erythrocyte; peripheral circulation ID COMPUTERIZED IMAGE-ANALYSIS; HYDROSTATIC-PRESSURE; AGGREGATION; TRANSPORT; FLOW AB In vitro studies have shown that mild pressure increases red blood cell (RBC) aggregation. Enhanced RBC aggregation in pathologic states can drive the circulation into stasis. This investigation examined the effects of pressure on RBC aggregation in human volunteers. The hypothesis tested is that RBC aggregation is increased during hyperbaric exposure. Eleven subjects participated in dives to 300 feet of seawater (fsw) in a man-rated chamber complex. Blood samples were taken at the surface, at 66 fsw, and at 300 fsw. Data were analyzed with a repeated measures one-way analysis of variance for a complete randomized design. Statistical significance was achieved at P < 0.05. Data are expressed as mean +/- SEM. The median aggregate size (number of RBC/aggregate) of RBCs was significantly increased at depth. At a shear stress of 0.1 dyne/cm(2), median aggregate size was 12.0 +/- 2.1, 33.0 +/- 7.3, and 48.8 +/- 10.8 at the surface, at 66 fsw, and at 300 fsw, respectively. These results show that mild pressure increases RBC aggregation in the human circulation. C1 NIH, Natl Ctr Res Resources, Rockledge Ctr 1, Bethesda, MD 20892 USA. USN, Med Res Inst, Diving & Environm Physiol Dept, Bethesda, MD 20889 USA. Hebrew Univ Jerusalem, Hadassah Med Sch, Dept Biochem, IL-91120 Jerusalem, Israel. RP Taylor, WF (reprint author), NIH, Natl Ctr Res Resources, Rockledge Ctr 1, Ste 6030,6705 Rockledge Dr,MSC 7965, Bethesda, MD 20892 USA. NR 16 TC 7 Z9 7 U1 0 U2 1 PU UNDERSEA & HYPERBARIC MEDICAL SOC INC PI KENSINGTON PA 10531 METROPOLITAN AVE, KENSINGTON, MD 20895 USA SN 1066-2936 J9 UNDERSEA HYPERBAR M JI Undersea Hyperb. Med. PD FAL PY 1998 VL 25 IS 3 BP 167 EP 170 PG 4 WC Marine & Freshwater Biology; Medicine, Research & Experimental SC Marine & Freshwater Biology; Research & Experimental Medicine GA 125HJ UT WOS:000076231100004 PM 9789336 ER PT J AU Pauley, PM AF Pauley, PM TI An example of uncertainty in sea level pressure reduction SO WEATHER AND FORECASTING LA English DT Article ID SURFACE; GRADIENT; TERRAIN AB Difficulty analyzing mesoscale features in California and Nevada for a 1991 case study prompted a review of techniques for sea level pressure (SLP) reduction and an evaluation of the performance of the various techniques for the U.S. west coast states at 0000 UTC 30 November 1991. The objective of any SLP reduction procedure is to provide a pressure field that portrays meteorological features rather than terrain features, a difficult goal to meet in this region given the steep terrain gradients on the western slopes of the Sierra Nevada range. The review and evaluation are performed both for techniques applicable at individual stations and for techniques applicable at grid points in a model analysis or forecast. When using station data, one would like to perform a manual or objective analysis of SLP with the greatest number of stations possible by adding stations that report only altimeter setting to the stations that report both SLP and altimeter setting. The results of the comparison show that the incorporation of altimeter-setting stations into an analysis of SLP was found to be practical only at elevations less than 300 m. Above this, the standard reduction includes empirical corrections that cannot be easily duplicated, and the other reduction techniques yielded values that varied over a large enough range that the uncertainty associated with the choice of technique becomes too great to permit the analysis of weak mesoscale features. At such low elevations, the various techniques examined gave similar results; therefore, the simple reduction is recommended. In elevated plateau regions, a pressure analysis on a geopotential surface at approximately the mean terrain height is recommended to minimize reduction errors. No satisfactory solution was found for regions with sleep terrain gradients. Computing SLP from model objective analyses or forecasts that are in the model's native vertical coordinate, typically the terrain-following sigma coordinate, poses a different set of problems. The model terrain field is usually smoothed and so contains regions where it differs significantly from the actual terrain. This is sufficient in itself to yield reduction errors that have a coherent mesoscale signature. In addition, SLP fields computed using available techniques vary widely in areas of higher terrain elevation, sometimes producing mesoscale features that suspiciously coincide with terrain features and so suggest reduction error. These mesoscale pressure artifacts are also often associated with unrealistic geostrophic wind speed maxima. The Mesinger method of defining the below-ground temperature field by horizontal interpolation across terrain features after interpolating the model sigma-level objective analyses to pressure surfaces worked best for this case. It produced values that agreed reasonably well with the manual SLP analysis and with the 1300-m pressure analysis over Nevada, without generating an artificial geostrophic wind speed maximum. C1 USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Pauley, PM (reprint author), USN, Postgrad Sch, Dept Meteorol, Code MR-Pa,589 Dyer Rd,Room 254, Monterey, CA 93943 USA. NR 16 TC 20 Z9 20 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD SEP PY 1998 VL 13 IS 3 BP 833 EP 850 DI 10.1175/1520-0434(1998)013<0833:AEOUIS>2.0.CO;2 PN 2 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 130HD UT WOS:000076513400017 ER PT J AU Bakaltcheva, IB Shriver-Lake, LC Ligler, FS AF Bakaltcheva, IB Shriver-Lake, LC Ligler, FS TI A fiber optic biosensor for multianalyte detection: importance of preventing fluorophore aggregation SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article; Proceedings Paper CT 4th European Conference on Optical Chemical Sensors and Biosensors CY MAR 29-APR 01, 1998 CL MUNSTER, GERMANY DE fiber optics; biosensor; immunosensor; deoxycholic acid; TNT; RDX ID TNT AB Individual assays for the detection of the explosives hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6,-trinitrotoluene (TNT) with a fiber optic biosensor have been developed in our laboratory. The next step is to develop an assay for simultaneous detection of RDX and TNT, To obtain this goal, a mixture of the fluorescently-labeled analogs Cy5-EDA-RDH and Cy5-EDA-TNB used in the individual assays is run over anti-RDX and anti-TNT fiber probes connected in series. There is an increased total fluorophore concentration in the mixture which results in a significant increase in the normalized signal compared to that produced by a single fluorophore. Aggregation of the amphiphilic fluorophores in the mixture on the surface of the fiber optic probe is a possible reason for the observed effect. We explored the use of nonionic (Tween 20) and ionic detergents (deoxycholic acid) to block aggregate formation and allow analytical determination of RDX and TNT. Conditions are reported under which this is possible. (C) 1998 Elsevier Science S,A. All rights reserved. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. Geocenters Inc, Rockville, MD 20852 USA. RP Ligler, FS (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Code 6910,4855 Overlook Ave, Washington, DC 20375 USA. NR 12 TC 16 Z9 18 U1 1 U2 4 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 AUG 31 PY 1998 VL 51 IS 1-3 BP 46 EP 51 DI 10.1016/S0925-4005(98)00210-X PG 6 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 156WD UT WOS:000078024400007 ER PT J AU Roberts, M Lindsay, GA Stenger-Smith, JD Hollins, RA Chafin, AP Gratz, RF AF Roberts, M Lindsay, GA Stenger-Smith, JD Hollins, RA Chafin, AP Gratz, RF TI High glass transition temperature syndioregic second-order non-linear optical polymer in Langmuir-Blodgett-Kuhn films SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 8th International Conference on Organized Molecular Films CY AUG 24-29, 1997 CL PACIFIC GROVE, CALIFORNIA SP Stanford Univ, Ctr Polymer Interfaces & Macromolec Assemblies, Thin Solid Films, NIH DE multilayers; polymers; second-harmonic generation; Langmuir-Blodgett-Kuhn; structural aging ID 2ND-HARMONIC GENERATION AB We report here recent progress toward the goal of processing polymers near room temperature to produce all-polymeric non-linear optical films which may ultimately find application as active waveguides. Polymers designed for spin-casting were found to be processable by the Langmuir-Blodgett-Kuhn (LBK) technique. The T-g of the bulk polymer is about 240 degrees C. The temporal stability of non-centrosymmetric order in LBK films at elevated temperatures was followed by measurement of the second harmonic generated (SHG) light intensity. The SHG signal was found to be constant in LBK films heated at 95 degrees C for 10 h. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, NAWCWPNS, China Lake, CA 93555 USA. Mary Washington Coll, Dept Chem, Fredericksburg, VA 22401 USA. RP Roberts, M (reprint author), USN, NAWCWPNS, Code 4B2200D, China Lake, CA 93555 USA. NR 5 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD AUG 31 PY 1998 VL 327 BP 5 EP 8 DI 10.1016/S0040-6090(98)00576-8 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 124MX UT WOS:000076187000003 ER PT J AU Kim, OK Choi, LS Zhang, HY He, XH Shih, YH AF Kim, OK Choi, LS Zhang, HY He, XH Shih, YH TI A novel supramolecular self-assembly thin film with spontaneous polar order SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 8th International Conference on Organized Molecular Films CY AUG 24-29, 1997 CL PACIFIC GROVE, CALIFORNIA SP Stanford Univ, Ctr Polymer Interfaces & Macromolec Assemblies, Thin Solid Films, NIH DE self-assembly; polar order; supramolecules; non-linear optical materials ID LANGMUIR-BLODGETT-FILMS; 2ND HARMONIC-GENERATION; 2ND-HARMONIC GENERATION; HEMICYANINE DYES; AMYLOSE AB A novel supramolecular thin film in which a non-linear optical (NLO) chromophore is uniaxially included in the helical cavity of amylose, revealed a spontaneous self-assembly with a long-range polar order of the chromophores perpendicular to the film surface. This was manifested by a significantly large second harmonic generation (SHG) observed from solution-cast solid supramolecular thin films on a glass substrate without any external field. Such self-assembly/self-poling and the long-term polar stability of the supramolecular chromophores are thought to be due to the helical rigid-rod structure, their dipolar and/or chiral recognition in the ordering process following the polar initiation through the interface interaction of the chromophore with the glass substrate, and H-bonding among the ordered supramolecules. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21228 USA. RP Kim, OK (reprint author), USN, Res Lab, Div Chem, Washington, DC 20375 USA. NR 16 TC 11 Z9 11 U1 0 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD AUG 31 PY 1998 VL 327 BP 172 EP 175 DI 10.1016/S0040-6090(98)00622-1 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 124MX UT WOS:000076187000039 ER PT J AU Daehler, M Bevilacqua, RM Kriebel-Hamilton, DL Goldizen, D Olivero, JJ Hartmann, GK Degenhardt, W Richards, ML Connor, BJ Aellig, CP AF Daehler, M Bevilacqua, RM Kriebel-Hamilton, DL Goldizen, D Olivero, JJ Hartmann, GK Degenhardt, W Richards, ML Connor, BJ Aellig, CP TI Validation of millimeter-wave atmospheric sounder (MAS) ozone measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ERROR ANALYSIS; SPACE; UARS; SPECTROSCOPY; INSTRUMENT; RETRIEVAL; SHUTTLE; MIDDLE; CLO; O-3 AB This paper discusses the validation of measurements of O-3 distribution in the Earth's atmosphere made by the Millimeter-wave Atmospheric Sounder (MAS), a component of NASA's ATLAS spacelab shuttle package. Measurements of 184 GHz O-3 emission from the Earth's limb at tangent altitudes between 20 and 80 km were made with a 50 channel radiometer having a spectral resolution of 200 KHz. In three missions the emissions of O-3, H2O: ClO, and O-2 were measured between 70 degrees S and 70 degrees N latitudes. O-3 mixing ratio calculations and error analysis were performed with the Rodgers optimal estimation method. Data binned in 128 s batches yield mixing ratio profiles with an altitude resolution of 7 km at the O-3 peak and an estimated accuracy of 5%. Additional retrievals made with all data from each mission binned in 50 latitude zones yield mixing ratios with about 5 km altitude resolution and somewhat improved accuracy. Comparisons with coincident measurements from other space platforms indicate a general agreement within approximately 5%. The data are publicly available through the German Remote Sensing Data Center. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Computat Phys Inc, Fairfax, VA 22031 USA. USAF, Wright Patterson AFB, OH 45433 USA. Embry Riddle Aeronaut Univ, Dept Phys Sci, Daytona Beach, FL 32114 USA. Max Planck Inst Aeron, D-37189 Katlenburg Lindau, Germany. Natl Inst Water & Atmospher Res, Omakau, Cent Otago, New Zealand. RP Daehler, M (reprint author), USN, Res Lab, Remote Sensing Div, 4555 Overlook Ave SW,Code 7227, Washington, DC 20375 USA. EM daehler@rira.nrl.navy.mil; bevilacqu@map.nrl.navy; kriebel@kepler.cpi.com; dgoldize@afit.af.mil; oliveroj@db.erau.edu; ghartmann@linax1.dnet.gwdg.de; degenhardt@linax1.dnet.gwdg.de; richards@linax1.dnet.gwdg.de; connor@kea.lauder.cri.nz NR 25 TC 3 Z9 3 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD AUG 27 PY 1998 VL 103 IS D16 BP 19615 EP 19639 DI 10.1029/98JD01455 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 114ED UT WOS:000075595400015 ER PT J AU Ranganathan, D Haridas, V Kurur, S Thomas, A Madhusudanan, KP Nagaraj, R Kunwar, AC Sarma, AVS Karle, IL AF Ranganathan, D Haridas, V Kurur, S Thomas, A Madhusudanan, KP Nagaraj, R Kunwar, AC Sarma, AVS Karle, IL TI Demonstration of endo-cis-(2S,3R)-bicyclo[2.2.1]hept-5-en-2,3-dicarbonyl unit as a reverse-turn scaffold and nucleator of two-stranded parallel beta-sheets: Design, synthesis, crystal structure, and self-assembling properties of norborneno peptide analogues SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Review ID SECONDARY STRUCTURE MIMETICS; DE-NOVO DESIGN; PEPTIDOMIMETIC INHIBITORS; SOLUTION CONFORMATIONS; CHEMICAL SYNTHESIS; IMPROVED TRANSPORT; LOCAL STRUCTURES; PROTEIN DESIGN; DENOVO DESIGN; ALPHA-HELICES AB endo-cis-(2S,3R)-Bicyclo[2.2.1]hept-5-en (norbornene) dicarbonyl unit with a built-in U-architecture has been demonstrated to be an excellent reverse-turn molecular scaffold. A large variety of endo-cis-(2S,3R)-norborneno bispeptides containing almost all of the coded amino acids were synthesized and examined for conformational preferences by H-1 NMR, FT-IR, CD, and X-ray crystallographic studies. While FT-IR and H-1 NMR variable-temperature studies ruled out the presence of any significant amount of intramolecular hydrogen bonding in simple bispeptides (3a-h) (except in Aib bispeptide), the CD studies were clearly in favor of a beta-turn type structure. Single-crystal X-ray studies on Aib, Val and Leu containing norborneno bispeptides (3b-d) provided convincing proof for the presence of reverse-turn conformation. While the interstrand C-alpha-C-alpha' distances (5.2-5.7 Angstrom) were well within the range of those for beta-turn structures, no interstrand intramolecular hydrogen bonding was seen in Val and Leu bispeptides; the Aib bispeptide forms a seven-membered hydrogen-bonded ring, thus, showing that the norbornene (2S,3R)-dicarbonyl template assembles peptide chains in reverse-turn conformation by virtue of its built-in U-shaped architecture at these positions, and hydrogen bonding may not be necessary to stabilize the turn structure. The endo-cis-(2S,3R) orientation of bispeptide chains is essential for turn structure as shown by the crystal structure of trans-(2R, 3R) and trans-(2S,3S) derivative of Val bispeptide wherein the two peptide chains move away from each other with the C-alpha-C-alpha' distance increasing to 7.1-8.2 Angstrom. The norbornene 5,6-double bond was hydrogenated to 5,6-dihydro derivative which showed almost the same CD spectrum as its olefinic analogue. Oxidative cleavage [Ru (VIII)] of the 5,6-double bond in norborneno bispeptides, as demonstrated with Leu bispeptide, afforded novel cyclopentanoid peptide analogues. The promise of norbornene unit as a template for nucleating the formation of two-stranded parallel beta-sheets with minimum structural complexity is shown by the preparation of higher members of norborneno bispeptides with the general structure NBE(Pep)(2) [NBE = endo-cis-(2S,3R)-bicyclo[2.2.1]hept-5-en (norbornene) dicarbonyl unit; Pep = peptide strand with two, three, or four (same or different) amino acid residues]. In H-1 NMR, the high (3)J(HN alpha) values (7.0-9.3 Hz) observed for the amide protons (Table 5) coupled with the presence of medium to strong intrastrand sequential ROE connectivities d(alpha N(i,i+1)) spanning the entire three- or four-residue sequence in the peptide strands of 9a-e and 10 and the exhibition of relatively low-temperature coefficients (d delta/dT = -0.2 to -3.4 ppb/K) for amide protons in DMSO-d(6) solvent (Table 4) clearly suggested that hydrogen-bonded beta-sheet conformers dominate the population. FT-IR and CD studies provided further support for parallel beta-sheet structures. A particularly unique feature of the norborneno bispeptides is their strong tendency to self-assemble in the solid state. Thus, while endo-cis-(2S,3R)-Aib bispeptide (3b) forms 16-membered hydrogen bonded centrosymmetric dimers, the half-ester half-acid and the dicarboxylic acid derivatives of 3b self-assemble to form highly ordered hydrogen-bonded molecular ribbons. The Val and Leu cis-(2S, 3R)-bispeptides organize into hydrogen-bonded chains and the trans isomer of Val bispeptide self-assembles into hydrogen-bonded beta-sheet ribbon. C1 CSIR, Reg Res Lab, Biomol Res Unit, Trivandrum 695019, Kerala, India. Cent Drug Res Inst, Lucknow 226001, Uttar Pradesh, India. Ctr Cellular & Mol Biol, Hyderabad 500007, Andhra Pradesh, India. Indian Inst Chem Technol, Hyderabad 500007, Andhra Pradesh, India. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Ranganathan, D (reprint author), CSIR, Reg Res Lab, Biomol Res Unit, Trivandrum 695019, Kerala, India. RI V, haridas/K-2992-2012; TVM, NIIST/E-5132-2012 OI TVM, NIIST/0000-0002-5814-466X NR 106 TC 51 Z9 51 U1 1 U2 6 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 AUG 26 PY 1998 VL 120 IS 33 BP 8448 EP 8460 DI 10.1021/ja980143+ PG 13 WC Chemistry, Multidisciplinary SC Chemistry GA 114PX UT WOS:000075618900018 ER PT J AU Efros, AL Rosen, M AF Efros, AL Rosen, M TI Comment on "Comparison of the k center dot p and the direct diagonalization approaches for describing the electron structure of quantum dots" SO APPLIED PHYSICS LETTERS LA English DT Editorial Material ID ASSIGNMENT; SPECTRUM C1 USN, Nanostruct Opt Sect, Res Lab, Washington, DC 20375 USA. RP Efros, AL (reprint author), USN, Nanostruct Opt Sect, Res Lab, Washington, DC 20375 USA. NR 14 TC 15 Z9 15 U1 1 U2 5 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 AUG 24 PY 1998 VL 73 IS 8 BP 1155 EP 1156 DI 10.1063/1.122114 PG 2 WC Physics, Applied SC Physics GA 113UN UT WOS:000075572000047 ER PT J AU Bollt, EM Kostelich, EJ AF Bollt, EM Kostelich, EJ TI Optimal targeting of chaos SO PHYSICS LETTERS A LA English DT Article ID PERIODIC-ORBITS; SYSTEMS; ATTRACTORS AB Standard graph theoretic algorithms are applied to chaotic dynamical systems to identify orbits that are optimal relative to a prespecified cost function. We reduce the targeting problem to the problem of finding optimal paths through a graph. Numerical experiments on one-dimensional maps suggest that periodic saddle orbits of low period are typically less expensive to target (relative to a family of smooth cost functions) than periodic saddle orbits of high period. (C) 1998 Elsevier Science B.V. C1 USN Acad, Dept Math, Annapolis, MD 21402 USA. Arizona State Univ, Dept Math, Tempe, AZ 85287 USA. RP Bollt, EM (reprint author), USN Acad, Dept Math, 572 Holloway Rd, Annapolis, MD 21402 USA. NR 22 TC 22 Z9 22 U1 0 U2 0 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 AUG 24 PY 1998 VL 245 IS 5 BP 399 EP 406 DI 10.1016/S0375-9601(98)00270-9 PG 8 WC Physics, Multidisciplinary SC Physics GA 112YN UT WOS:000075522600011 ER PT J AU Baker, AD Yen, MW Donovan, RJ Morgan, RJ George, C AF Baker, AD Yen, MW Donovan, RJ Morgan, RJ George, C TI X-ray analysis of novel organic aromatic salts and precursors SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 CUNY Queens Coll, Dept Chem & Biochem, Flushing, NY 11367 USA. Fordham Univ, Dept Chem, Bronx, NY 10458 USA. Marshall Univ, Huntington, WV 25755 USA. USN, Res Lab, Struct Matter Lab, 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 252-INOR BP U74 EP U74 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WY UT WOS:000075235000253 ER PT J AU Balderson, SD Nivens, DA Lacy, WB Conrad, DW AF Balderson, SD Nivens, DA Lacy, WB Conrad, DW TI Silane stability on silicon surfaces as measured by variable angle spectroscopic ellipsometry, AFM, and contact angle measurements. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Geocenters Inc, Rockville, MD 20852 USA. USN, Res Lab, 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 063-ANYL BP U158 EP U158 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WX UT WOS:000075234900405 ER PT J AU Bitterwolf, TE Saygh, A Bays, JT Shade, JE AF Bitterwolf, TE Saygh, A Bays, JT Shade, JE TI Frozen Nujol matrix and solution photochemistry of linked cyclopentadienyl-allyl compounds of molybdenum and chromium. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Idaho, Dept Chem, Moscow, ID 83844 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 562-INOR BP U170 EP U170 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WY UT WOS:000075235000562 ER PT J AU Brady, RF Schmidt, DL AF Brady, RF Schmidt, DL TI Low bioadhesion on self-assembled fluoropolymer surfaces. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Mat Chem Branch, Washington, DC 20375 USA. Dow Chem Co, Cent Res & Dev, Adv Polymer Syst Lab, Midland, MI 48674 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 241-POLY BP U72 EP U72 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100240 ER PT J AU Conrad, DW Nivens, DA Balderson, SD Lacy, WB AF Conrad, DW Nivens, DA Balderson, SD Lacy, WB TI Hydrolytic stability of poly(ethylene glycol) organosilane monolayers. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. GEO CENTERS, Rockville, MD 20852 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 027-PHYS BP U631 EP U631 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WY UT WOS:000075235001972 ER PT J AU Donovan, RJ George, C Morgan, RJ AF Donovan, RJ George, C Morgan, RJ TI Instantaneous and tunable fluorescence with thioformamides SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 CUNY Queens Coll, Dept Chem & Biochem, Flushing, NY 11367 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. Marshall Univ, Dept Chem, Huntington, WV 25755 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 251-INOR BP U73 EP U74 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 107WY UT WOS:000075235000252 ER PT J AU Green, JBD Novoradovsky, A Lee, GU Colton, RJ AF Green, JBD Novoradovsky, A Lee, GU Colton, RJ TI A novel platform for improving force measurements with scanning probe microscopy. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Surface Chem Div, Washington, DC 20375 USA. RI Lee, Gil/P-8696-2016 OI Lee, Gil/0000-0002-7949-5848 NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 317-COLL BP U676 EP U676 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WX UT WOS:000075234902002 ER PT J AU Green, JBD Novoradovsky, A Lee, GU Colton, RJ AF Green, JBD Novoradovsky, A Lee, GU Colton, RJ TI Force measurements with scanning probe microscopy: A controlled approach to avoid the problems associated with damage, coverage, and fouling. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Surface Chem Div, Washington, DC 20375 USA. RI Lee, Gil/P-8696-2016 OI Lee, Gil/0000-0002-7949-5848 NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 146-COLL BP U625 EP U625 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WX UT WOS:000075234901831 ER PT J AU Herman, WN Roberts, MJ Stenger-Smith, JD Chafin, AP Hollins, RA Lindsay, GA Wynne, KJ AF Herman, WN Roberts, MJ Stenger-Smith, JD Chafin, AP Hollins, RA Lindsay, GA Wynne, KJ TI Persistent in-plane order through 90 bilayers in an accordion polymer LB film. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NAWC, WD, China Lake, CA 93555 USA. Off Naval Res, Arlington, VA 22217 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 586-POLY BP U175 EP U175 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100582 ER PT J AU Jha, SK Cheon, KS Green, MM Selinger, JV AF Jha, SK Cheon, KS Green, MM Selinger, JV TI Materials-chirality: Majority rules among the sergeants. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. Polytech Univ, Polymer Res Inst, Metrotech Ctr 6, Brooklyn, NY 11201 USA. RI Selinger, Jonathan/D-1445-2010 OI Selinger, Jonathan/0000-0002-4982-2457 NR 0 TC 0 Z9 0 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 069-POLY BP U21 EP U21 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100070 ER PT J AU Kurihara, LK Chow, GM Everett, RK AF Kurihara, LK Chow, GM Everett, RK TI Chemical synthesis of nanostructured metallic and ceramic coatings and powders. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. Potomac Res Int, Fairfax, VA 22030 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 066-MACR BP U318 EP U318 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100972 ER PT J AU Lacy, WB Vittal, VR Turner, DC Conrad, DW Gaber, BP AF Lacy, WB Vittal, VR Turner, DC Conrad, DW Gaber, BP TI An LFM biosensor based on protein patterning of photoactive PEG-silane and photobiotin surfaces. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Ctr Biomol Sci & Engn, 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 039-ANYL BP U153 EP U153 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WX UT WOS:000075234900388 ER PT J AU Lopez, JL Wang, ZG Hsiao, BS Armistead, PJ AF Lopez, JL Wang, ZG Hsiao, BS Armistead, PJ TI Dynamic structure development during isothermal crystallization and melting of linear polyethylenes SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. USN, Res Lab, Mat Chem Branch, Washington, DC 20375 USA. RI Wang, Zhigang/F-6136-2010 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 178-PMSE BP U867 EP U867 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WY UT WOS:000075235002607 ER PT J AU Mera, AE Wynne, KJ AF Mera, AE Wynne, KJ TI A new approach to fluorosilicone elastomers. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Mat Chem Branch, Washington, DC 20375 USA. Off Naval Res, Phys Sci S&T Div, Arlington, VA 22217 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 211-POLY BP U63 EP U63 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100210 ER PT J AU Provenzano, V AF Provenzano, V TI Fullerene-reinforced nanocomposites. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Div Mat Sci & Technol, Phys Met Branch, 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 078-MACR BP U322 EP U322 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100984 ER PT J AU Roberts, MJ Lindsay, GA Wynne, KJ AF Roberts, MJ Lindsay, GA Wynne, KJ TI Polar films for nonlinear optics formed by alternating polyelectrolyte deposition. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Air Warfare Ctr, Weapons Div, Chem & Mat Branch, China Lake, CA 93555 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 626-POLY BP U203 EP U203 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100623 ER PT J AU Rolison, DR Long, JW Morris, CA Anderson, ML Merzbacher, CI AF Rolison, DR Long, JW Morris, CA Anderson, ML Merzbacher, CI TI Synthesis and characterization of aerogels as integrated, networked, nanostructured electrocatalysts. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 003-CATL BP U279 EP U279 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100849 ER PT J AU Sastri, SB Keller, TM AF Sastri, SB Keller, TM TI Phthalonitrile polymer for high temperature applications. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Div Chem, Mat Chem Branch, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 078-POLY BP U24 EP U24 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100078 ER PT J AU Schoen, PE Singh, A AF Schoen, PE Singh, A TI Role of giant vesicles from diacetylenic phospholipids in the development of colorimetric detection for receptor - Ligand interaction. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Ctr Biomol Sci & Engn, 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 113-IEC BP U945 EP U945 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WX UT WOS:000075234902791 ER PT J AU Snow, AW Buckley, LJ Armistead, JP AF Snow, AW Buckley, LJ Armistead, JP TI Fluoromethylene cyanate ester resins. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 202-POLY BP U60 EP U60 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100201 ER PT J AU Watanabe, M Soosaar, K Chun, HM AF Watanabe, M Soosaar, K Chun, HM TI Multigranular molecular dynamics simulations of Bacteriorhodopsin. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Moldyn Inc, Cambridge, MA 02139 USA. Univ New Orleans, New Orleans, LA 70148 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Virginia, Dept Mat Sci, Charlottesville, VA 22903 USA. Mat Directorate, Wright Patterson AFB, OH USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 101-PHYS BP U687 EP U687 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WY UT WOS:000075235002046 ER PT J AU Yoo, CH Yee, RY Zarras, P AF Yoo, CH Yee, RY Zarras, P TI Optical loss characterization methods of thin organic polymer films. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Air Warfare Weap Div, Lasers & Opt Sect, China Lake, CA 93555 USA. USN, Air Warfare Weap Div, Mat Characterizat Sect, China Lake, CA 93555 USA. USN, Air Warfare Weap Div, Mat Synthesis Sect, China Lake, CA 93555 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 23 PY 1998 VL 216 MA 629-POLY BP U204 EP U204 PN 3 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 107WZ UT WOS:000075235100626 ER PT J AU Kidwell, DA Holland, JC Athanaselis, S AF Kidwell, DA Holland, JC Athanaselis, S TI Testing for drugs of abuse in saliva and sweat SO JOURNAL OF CHROMATOGRAPHY B LA English DT Review DE reviews; sweat; saliva; drugs of abuse ID CHROMATOGRAPHY MASS-SPECTROMETRY; TOBACCO-SMOKE EXPOSURE; PERFORMANCE LIQUID-CHROMATOGRAPHY; ETHANOL CONCENTRATIONS; PAROTID-SALIVA; BODY-FLUIDS; HUMAN-HAIR; COTININE CONCENTRATIONS; HEALTHY-VOLUNTEERS; COLLECTION DEVICE AB The detection of marijuana, cocaine, opiates, amphetamines, benzodiazepines, barbiturates, PCP, alcohol and nicotine in saliva and sweat is reviewed, with emphasis on forensic applications. The short window of detection and lower levels of drugs present compared to levels found in urine limits the applications of sweat and saliva screening for drug use determination. However, these matrices may be applicable for use in driving while intoxicated and surveying populations far illicit drug use. Although not an illicit drug, the detection of ethanol is reviewed because of its importance in driving under the influence. Only with alcohol may saliva be used to estimate blood levels and the degree of impairment because of the problems with oral contamination and drug concentrations varying depending upon how the saliva is obtained. The detection of nicotine and cotinine (from smoking tobacco) is also covered because of its use in Life insurance screening and surveying for passive exposure. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Div Chem, Res Lab, Washington, DC 20375 USA. Geocenters Inc, Ft Washington, MD 20744 USA. Univ Athens, Dept Forens Med & Toxicol, Athens 11527, Greece. RP Kidwell, DA (reprint author), USN, Div Chem, Res Lab, Washington, DC 20375 USA. NR 204 TC 150 Z9 151 U1 7 U2 69 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4347 J9 J CHROMATOGR B JI J. Chromatogr. B PD AUG 21 PY 1998 VL 713 IS 1 BP 111 EP 135 DI 10.1016/S0378-4347(97)00572-0 PG 25 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 103EG UT WOS:000075144600007 PM 9700555 ER PT J AU Berghmans, D Clette, F Moses, D AF Berghmans, D Clette, F Moses, D TI Quiet Sun EUV transient brightenings and turbulence - A panoramic view by EIT on board SOHO SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : corona; Sun : transition region; Sun : UV radiation; turbulence ID TELESCOPE POWER SPECTRA; SOLAR ACTIVE REGIONS; X-RAY-EMISSION; TRANSITION REGION; MHD-TURBULENCE; CORONA; NANOFLARES; ENERGY; ULTRAVIOLET; MICROFLARES AB Since January 1996, the Extreme-Ultraviolet Imaging Telescope (EIT, onboard SOHO) has produced unique image sequences covering a wide field of view with a high temporal resolution, in the He II transition region line and in several Fe coronal emission lines. Using two sequences acquired with cadences of the order of one minute and with durations ranging from one hour to several hours, we analyse the dynamical properties of the transition region and corona. We find evidence of turbulence both in spatial and in temporal power spectra suggesting that the plasma of the quiet solar atmosphere is in a permanent state of turbulence. As predicted by numerical simulations, this turbulence has an highly intermittent nature. We find an unexpectedly large number of small-scale brightenings. The coronal brightenings are identified as the low energy counterparts of "X-ray network flares" observed with SXT on board Yohkoh. The thousands of brightenings observed by EIT in the transition region include many that are similar to "blinkers" observed with CDS, though we find a larger variety. Thanks to EIT's wide spatial coverage, we can perform a large scale statistical study, complementing spectroscopic studies which give access to only a very small subsample of events. We present occurrence distributions of duration, size and radiative output of the brightenings as well as various correlations between these parameters. The energy injected by the brightenings into the solar atmosphere is insufficient to be in itself responsible for coronal heating. We discuss the importance of the ubiquitous small brightenings as perhaps the most visible aspect of yet undetected heating events higher up in the quiet corona. C1 Observ Royal Belgique, B-1180 Brussels, Belgium. USN, Res Lab, Washington, DC 20375 USA. RP Berghmans, D (reprint author), Observ Royal Belgique, Ringlaan 3, B-1180 Brussels, Belgium. EM David.Berghmans@ksb-orb.oma.be NR 50 TC 121 Z9 121 U1 0 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD AUG 20 PY 1998 VL 336 IS 3 BP 1039 EP 1055 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 118FL UT WOS:000075827700040 ER PT J AU Keenan, FP Pinfield, DJ Woods, VJ Reid, RHG Conlon, ES Pradhan, AK Zhang, HL Widing, KG AF Keenan, FP Pinfield, DJ Woods, VJ Reid, RHG Conlon, ES Pradhan, AK Zhang, HL Widing, KG TI Extreme ultraviolet transitions of Ca XVI in solar flare and laboratory spectra SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic data; atomic processes; methods : laboratory; Sun : flares; Sun : UV radiation ID B-LIKE IONS; ELECTRON-IMPACT EXCITATION; BORON-LIKE IONS; ATOMIC DATA; RATE COEFFICIENTS; IRON PROJECT; LINE RATIOS; SPECTROSCOPIC DIAGNOSTICS; ISOELECTRONIC SEQUENCE; XUV OBSERVATIONS AB New R-matrix calculations of electron impact excitation rates for transitions among the 2s(2)2p, 2s2p(2), and 2p(3) levels of Ca XVI are presented. These data are subsequently used, in conjunction with recent estimates for proton excitation rates, to derive theoretical electron density sensitive emission-line ratios involving 2s(2)2p-2s2p(2) transitions in the similar to 155-225 Angstrom wavelength range. A comparison of these with observational data for solar flares, obtained with the Naval Research Laboratory's S082A spectrograph on board Skylab, reveals excellent agreement between theory and observation. In addition, the theoretical ratios compare favorably with those measured from the TEXT tokamak plasma, for which the electron temperature and density have been independently determined. This provides experimental support for the accuracy of the atomic data, and hence line ratio calculations, employed in the present analysis. C1 Queens Univ Belfast, Dept Pure & Appl Phys, Belfast BT7 1NN, Antrim, North Ireland. Queens Univ Belfast, Dept Appl Math & Theoret Phys, Belfast BT7 1NN, Antrim, North Ireland. Armagh Planetarium, Armagh BT61 9DB, North Ireland. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. USN, EO Hulburt Ctr Space Res, Res Lab, Washington, DC 20375 USA. RP Keenan, FP (reprint author), Queens Univ Belfast, Dept Pure & Appl Phys, Belfast BT7 1NN, Antrim, North Ireland. NR 41 TC 12 Z9 12 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 AUG 20 PY 1998 VL 503 IS 2 BP 953 EP 958 DI 10.1086/306028 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KN UT WOS:000077776700040 ER PT J AU Deniel, C Bevilacqua, RM Pommereau, JP Lefevre, F AF Deniel, C Bevilacqua, RM Pommereau, JP Lefevre, F TI Arctic chemical ozone depletion during the 1994-1995 winter deduced from POAM II satellite observations and the REPROBUS three-dimensional model SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STRATOSPHERIC POLAR VORTEX; UARS MLS; CLO; VALIDATION; HOLE AB Chemical ozone depletion during the unusually cold 1994-1995 Arctic winter is quantified using ozone profile measurements from the space-based Polar Ozone and Aerosol Measurement (POAM II) instrument and the REPROBUS three-dimensional chemistry transport model. The model is first used to determine the dynamical component of the observed variations, allowing the chemical component to be quantified from the observations. This technique has been previously used to estimate ozone loss from ground based total column measurements. In the present study, it has been adapted to the POAM II vertical profile measurements in order to document the vertical evolution of ozone chemical loss throughout the winter both inside and outside the polar vortex. The cumulative ozone loss thus obtained inside the vortex at the end of the winter is found to reach a maximum of 51% (with respect to the REPROBUS dynamics-only prediction) at the 430 K potential temperature level. The largest ozone depletion rates were observed in late January when record low temperatures were reported, and the vortex was largely displaced towards midlatitudes. The maximum depletion rate was 1.4%/d occurring at the 470 K potential temperature level. Smaller but significant chemical ozone depletion was also found outside the vortex, where cumulative ozone losses of 19% were observed in the lower stratosphere. Finally, comparison of chemical ozone loss inferred from the POAM measurements with that obtained from the REPROBUS model indicates that the model underestimates cumulative ozone loss inside the vortex (by similar to 30% in the lower stratosphere). C1 USN, Remote Sensing Div, Res Lab, Washington, DC 20375 USA. CNRS, Serv Aeron, F-91371 Verrieres Le Buisson, France. Ctr Natl Rech Meteorol, Meteo France, F-31057 Toulouse, France. RP Deniel, C (reprint author), USN, Remote Sensing Div, Res Lab, Washington, DC 20375 USA. EM deniel@poamb.nrl.navy.mil NR 43 TC 43 Z9 43 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD AUG 20 PY 1998 VL 103 IS D15 BP 19231 EP 19244 DI 10.1029/98JD01446 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 112LE UT WOS:000075495500024 ER PT J AU Campillo, AJ Eversole, JD Lin, HB AF Campillo, AJ Eversole, JD Lin, HB TI Further comment on the existence of a modified hydrogen bonding ratio in laboratory-generated water droplets SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Editorial Material ID LIQUID AEROSOL INTERFACE; ATMOSPHERIC CHEMISTRY; SPECTROSCOPIC TOUR; MICRODROPLETS; TEMPERATURE; EMISSION AB We offer further comments regarding the controversial claim of Zhang er nl. [1994] that a standard vibrating orifice aerosol generator modifies the hydrogen bonding ratio of laboratory water droplets. New data reported here fail to support their observation of a surface charge induced Raman spectral change as reported by Aker ct nl. [1996a]. C1 USN, Opt Phys Branch, Res Lab, Washington, DC 20375 USA. RP Campillo, AJ (reprint author), USN, Opt Phys Branch, Res Lab, Code 5610, Washington, DC 20375 USA. EM campillo@nrl.navy.mil NR 25 TC 5 Z9 5 U1 1 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 AUG 20 PY 1998 VL 103 IS D15 BP 19271 EP 19275 DI 10.1029/97JD00934 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 112LE UT WOS:000075495500027 ER PT J AU Barvosa-Carter, W Aziz, MJ Gray, LJ Kaplan, T AF Barvosa-Carter, W Aziz, MJ Gray, LJ Kaplan, T TI Kinetically driven growth instability in stressed solids SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHASE EPITAXIAL-GROWTH; NONHYDROSTATIC STRESS; CRYSTAL-GROWTH; AMORPHOUS SI; TRANSITION; DEPENDENCE; ROUGHNESS; STABILITY; STRAIN AB We report a new stress-induced kinetically driven morphological instability for driven systems. The effect of stress on the interfacial mobility couples to stress variations along a perturbed planar growth front. Comparison of theory and experiment for solid phase epitaxy at a corrugated Si(001) interface, with no free parameters, indicates that the new mechanism is required to account for the observed growth of the corrugation amplitude. This mechanism operates in conjunction with known diffusional and elastic strain energy-driven instabilities in determining morphological evolution. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Barvosa-Carter, W (reprint author), USN, Res Lab, Code 6177, Washington, DC 20375 USA. NR 26 TC 66 Z9 66 U1 3 U2 14 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 AUG 17 PY 1998 VL 81 IS 7 BP 1445 EP 1448 DI 10.1103/PhysRevLett.81.1445 PG 4 WC Physics, Multidisciplinary SC Physics GA 110UC UT WOS:000075398100024 ER PT J AU Kiriakidis, K Grivas, A Tzes, A AF Kiriakidis, K Grivas, A Tzes, A TI Quadratic stability analysis of the Takagi-Sugeno fuzzy model SO FUZZY SETS AND SYSTEMS LA English DT Article DE fuzzy model; control theory; quadratic stability; perturbed system; fuzzy model-based control ID CONTROL-SYSTEMS; IDENTIFICATION; DESIGN AB The nonlinear dynamic Takagi-Sugeno fuzzy model with offset terms is analyzed as a perturbed linear system. A sufficient criterion for the robust stability of this nominal system against nonlinear perturbations guarantees quadratic stability of the fuzzy model. The criterion accepts a convex programming formulation of reduced computational cost compared to the common Lyapunov matrix approach. Parametric robust control techniques suggest synthesis tools for stabilization of the fuzzy system. Application examples on fuzzy models of nonlinear plants advocate the efficiency of the method. The examples demonstrate reduced conservatism compared to norm-based criteria. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Polytech Univ, Dept Mech Engn, Metrotech Ctr 6, Brooklyn, NY 11201 USA. RP Kiriakidis, K (reprint author), USN Acad, Dept Weap & Syst Engn, 105 Maryland Ave, Annapolis, MD 21402 USA. OI Tzes, Anthony/0000-0003-3709-2810 NR 22 TC 29 Z9 29 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-0114 J9 FUZZY SET SYST JI Fuzzy Sets Syst. PD AUG 16 PY 1998 VL 98 IS 1 BP 1 EP 14 DI 10.1016/S0165-0114(96)00390-9 PG 14 WC Computer Science, Theory & Methods; Mathematics, Applied; Statistics & Probability SC Computer Science; Mathematics GA ZW338 UT WOS:000074400900001 ER PT J AU Cowan, DN Gray, GC DeFraites, RF AF Cowan, DN Gray, GC DeFraites, RF TI Counterpoint: Responding to inadequate critique of birth defects paper SO AMERICAN JOURNAL OF EPIDEMIOLOGY LA English DT Editorial Material ID PERSIAN-GULF-WAR; VETERANS C1 Exponent Hlth Grp, Landover, MD 20785 USA. USN, Hlth Res Ctr, San Diego, CA 92152 USA. Off Army Surgeon Gen, Falls Church, VA USA. RP Cowan, DN (reprint author), Exponent Hlth Grp, 8201 Corp Dr,Suite 680, Landover, MD 20785 USA. NR 11 TC 6 Z9 6 U1 1 U2 1 PU JOHNS HOPKINS UNIV SCHOOL HYGIENE PUB HEALTH PI BALTIMORE PA 111 MARKET PLACE, STE 840, BALTIMORE, MD 21202-6709 USA SN 0002-9262 J9 AM J EPIDEMIOL JI Am. J. Epidemiol. PD AUG 15 PY 1998 VL 148 IS 4 BP 326 EP 327 PG 2 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 109VN UT WOS:000075344700003 PM 9717874 ER PT J AU Gray, GC Knoke, JD Berg, SW Wignall, FS Barrett-Connor, E AF Gray, GC Knoke, JD Berg, SW Wignall, FS Barrett-Connor, E TI Counterpoint: Responding to suppositions and misunderstandings SO AMERICAN JOURNAL OF EPIDEMIOLOGY LA English DT Editorial Material ID PERSIAN-GULF-WAR; UNITED-STATES-NAVY C1 USN, Hlth Res Ctr, Emerging Illness Div, San Diego, CA 92186 USA. Hampton Hlth Dept, Hampton, VA USA. AEA Int, Irian Jaya, Indonesia. Univ Calif San Diego, Sch Med, Dept Family & Prevent Med, San Diego, CA 92103 USA. RP Gray, GC (reprint author), USN, Hlth Res Ctr, Emerging Illness Div, Box 85122, San Diego, CA 92186 USA. NR 51 TC 31 Z9 31 U1 2 U2 2 PU JOHNS HOPKINS UNIV SCHOOL HYGIENE PUB HEALTH PI BALTIMORE PA 111 MARKET PLACE, STE 840, BALTIMORE, MD 21202-6709 USA SN 0002-9262 J9 AM J EPIDEMIOL JI Am. J. Epidemiol. PD AUG 15 PY 1998 VL 148 IS 4 BP 328 EP 333 PG 6 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 109VN UT WOS:000075344700004 PM 9717875 ER PT J AU Hyams, KC Roswell, RH AF Hyams, KC Roswell, RH TI Resolving the Gulf War syndrome question SO AMERICAN JOURNAL OF EPIDEMIOLOGY LA English DT Article ID US VETERANS C1 USN, Med Res Inst, Div Epidemiol, Rockville, MD 20852 USA. RP Hyams, KC (reprint author), USN, Med Res Inst, Div Epidemiol, 12300 Washington Ave, Rockville, MD 20852 USA. NR 34 TC 13 Z9 13 U1 2 U2 2 PU JOHNS HOPKINS UNIV SCHOOL HYGIENE PUB HEALTH PI BALTIMORE PA 111 MARKET PLACE, STE 840, BALTIMORE, MD 21202-6709 USA SN 0002-9262 J9 AM J EPIDEMIOL JI Am. J. Epidemiol. PD AUG 15 PY 1998 VL 148 IS 4 BP 339 EP 342 PG 4 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 109VN UT WOS:000075344700006 PM 9717876 ER PT J AU Gray, GC Hawksworth, AW Smith, TC Kang, HK Knoke, JD Gackstetter, GD AF Gray, GC Hawksworth, AW Smith, TC Kang, HK Knoke, JD Gackstetter, GD TI Gulf War veterans' health registries. Who is most likely to seek evaluation? SO AMERICAN JOURNAL OF EPIDEMIOLOGY LA English DT Article DE diagnosis; military medicine; Persian Gulf syndrome; risk factors; veterans ID OPERATION-DESERT-STORM; PERSIAN-GULF; SHIELD AB Since the Persian Gulf War ended in 1991, many veterans have sought medical evaluation in the Department of Veterans Affairs Persian Gulf Veterans' Health Registry (VA registry) or the Department of Defense's Comprehensive Clinical Evaluation Program (DoD registry). Using combined data collected from 1993 to 1997 from the VA and DoD registries, the authors compared the characteristics of registry participants (n = 74,653) with those of all Gulf War veterans (n = 696,531) to determine the personnel most likely to seek medical evaluation. Using multiple logistic regression, the authors found that service branch and type were strongly associated with registry participation, with Army (adjusted odds ratio (OR) = 4.7, 95% confidence interval (CI) 4.6-4.9) and National Guard (OR = 2.6, 95% CI 2.5-2.6) personnel at highest odds compared with reference category personnel. Registry participants also were more likely to have been stationed in the Gulf War theater during the fighting (OR = 2.2), to be older(>31 years/<22 years OR = 2.1), to have been an enlisted person (OR = 2.0), to have been construction workers (OR = 1.3), to be female (OR = 1.3), and to have been hospitalized during the 12-month period before the war (OR = 1.2). These findings are useful in generating hypotheses regarding postwar morbidity. They also suggest that subpopulations of Gulf War veterans have a higher prevalence of symptoms and merit further study. C1 USN, Hlth Res Ctr, Emerging Illness Div, San Diego, CA 92186 USA. Dept Vet Affairs, Environm Epidemiol Serv, Washington, DC USA. Uniformed Serv Univ Hlth Sci, Bethesda, MD 20814 USA. RP Gray, GC (reprint author), USN, Hlth Res Ctr, Emerging Illness Div, POB 85122, San Diego, CA 92186 USA. NR 24 TC 46 Z9 46 U1 2 U2 2 PU JOHNS HOPKINS UNIV SCHOOL HYGIENE PUB HEALTH PI BALTIMORE PA 111 MARKET PLACE, STE 840, BALTIMORE, MD 21202-6709 USA SN 0002-9262 J9 AM J EPIDEMIOL JI Am. J. Epidemiol. PD AUG 15 PY 1998 VL 148 IS 4 BP 343 EP 349 PG 7 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 109VN UT WOS:000075344700007 PM 9717877 ER PT J AU Ligler, FS Anderson, GP Davidson, PT Foch, RJ Ives, JT King, KD Page, G Stenger, DA Whelan, JP AF Ligler, FS Anderson, GP Davidson, PT Foch, RJ Ives, JT King, KD Page, G Stenger, DA Whelan, JP TI Remote sensing using an airborne biosensor SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID FIBER OPTIC BIOSENSOR AB There is no current method for remote identification of aerosolized bacteria. In particular, such a capability is required to warn of a biological warfare attack prior to human exposure. A fiber optic biosensor, capable of running four simultaneous immunoassays, was integrated with an automated fluidics unit, a cyclone-type air sampler, a radio transceiver, and batteries on a small, remotely piloted airplane capable of carrying a 4.5-kg payload. The biosensor system was able to collect aerosolized bacteria in flight, identify them, and transmit the data to the operator on the ground. The results demonstrate the feasibility of integrating a biosensor into a portable, remotely operated system for environmental analysis. C1 USN, Res Lab, Washington, DC 20375 USA. Georgetown Univ, Washington, DC 20007 USA. Geocenters Inc, Ft Washington, MD 20744 USA. Kaman Sci Corp, Alexandria, VA 22308 USA. Nova Inc, Alexandria, VA 22308 USA. RP Ligler, FS (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM FLigler@CBMSE.NRL.Navy.mil RI Anderson, George/D-2461-2011 OI Anderson, George/0000-0001-7545-9893 NR 12 TC 42 Z9 44 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD AUG 15 PY 1998 VL 32 IS 16 BP 2461 EP 2466 DI 10.1021/es970991p PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 110KX UT WOS:000075380800015 ER PT J AU Carroll, JJ Koepke, ME Zintl, MW Gavrishchaka, V Ganguli, G AF Carroll, JJ Koepke, ME Zintl, MW Gavrishchaka, V Ganguli, G TI Velocity-shear origin of low-frequency electrostatic ion-gyroresonant waves SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CYCLOTRON TURBULENCE; ALFVEN WAVES; PLASMA; ACCELERATION; PARALLEL AB Electrostatic ion-cyclotron waves with spectral features below the ion gyrofrequency and spaced by small fractions of the ion gyrofrequency are reported, a result not possible for waves associated with the well-known current-driven electrostatic ion-cyclotron (CDEIC) instability. This is accomplished by producing a localized, transverse (to the magnetic field B (z) over cap) electric field E(x) (x) over cap in a laboratory plasma to excite inhomogeneous energy-density driven (IEDD) waves and by exploiting the k(y)v(E) dependence of the IEDD mode frequency, where k(y) and v(E) are the components of the IEDD wavevector and plasma drift speed, respectively, along the E x B direction. The IEDD frequency range is shown to reach down to one-third of the ion gyrofrequency, a range usually reserved for other types of waves, e.g., ion-acoustic waves. These results may be relevant to broadband ELF waves observed in the ionosphere. C1 W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA. USN, Res Lab, Washington, DC 20375 USA. RP Carroll, JJ (reprint author), Univ Michigan, Ann Arbor, MI 48109 USA. NR 24 TC 13 Z9 13 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 AUG 15 PY 1998 VL 25 IS 16 BP 3099 EP 3102 DI 10.1029/98GL02330 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 111WT UT WOS:000075462000011 ER PT J AU Veefkind, JP de Leeuw, G Durkee, PA AF Veefkind, JP de Leeuw, G Durkee, PA TI Retrieval of aerosol optical depth over land using two-angle view satellite radiometry during TARFOX SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ATSR-2 AB A new aerosol optical depth retrieval algorithm is presented that uses the two-angle view capability of the Along Track Scanning Radiometer 2 (ATSR-2). By combining the two-angle view and the spectral information this so-called dual view algorithm separates between aerosol and surface contributions to the top of the atmosphere radiance. First validation of the dual view algorithm was performed during the Tropospheric Aerosol Radiative Forcing Observational Experiment (TARFOX), which was conducted at the mid-Atlantic coast of the United States in July 1996. The satellite retrieved spectral aerosol optical depth is in good agreement with the aerosol optical depth from ground-based Sun/sky radiometers in three out of four cases. This shows the potential of aerosol retrieval over land using two-angle view satellite radiometry. C1 TNO, Phys & Elect Lab, NL-2509 JG The Hague, Netherlands. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Veefkind, JP (reprint author), TNO, Phys & Elect Lab, POB 96864, NL-2509 JG The Hague, Netherlands. EM veefkind@fel.tno.nl; deleeuw@fel.tno.nl; durkee@nps.navy.mil NR 12 TC 95 Z9 100 U1 2 U2 7 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 AUG 15 PY 1998 VL 25 IS 16 BP 3135 EP 3138 DI 10.1029/98GL02264 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 111WT UT WOS:000075462000021 ER PT J AU Dunlap, BI AF Dunlap, BI TI Quantum chemical molecular dynamics SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article; Proceedings Paper CT Symposium on Density Functional Theory and Applications CY JUN 03-07, 1997 CL DUKE UNIV, DURHAM, NORTH CAROLINA SP US Natl Sci Fdn, Corning Inc, Petr Res Fund, Amer Chem Soc, Univ N Carolina, NIH Computat Struct Biol Resource, NYU, Duke Univ, Off Vice Provost Acad & Int Affairs, Duke Univ, Dept Chem HO DUKE UNIV DE density functional; molecular dynamics; variational fitting; analytic X alpha; analytic derivatives ID DENSITY-FUNCTIONAL THEORY; BAND PHOTODISSOCIATION DYNAMICS; POTENTIAL-ENERGY SURFACES; NM PHOTODISSOCIATION; ORBITALS APPROACH; BASIS-SETS; OPTIMIZATION; RESOLUTION; IONIZATION; SYMMETRY AB Approximations can be consistent with the very high accuracy associated with traditional quantum chemistry provided that the approximations are variational. Variational approximations include the linear combination of atomic orbitals (LCAO) approximation of Hartree-Fock-Roothaan theory. In density functional theory, variationality usually requires that approximations be made in the expression for the energy which variationally yields the Kohn-Sham-Roothaan equations. These ideas are illustrated in a derivation of accurate forces for quantum chemical molecular dynamics using the very efficient analytic Xa method. This method is used to follow directly the time evolution of collisions in a collinear (NO)(12) system and the excited-state dynamics of ICN and ICH3 photodissociation. (C) 1998 John Wiley & Sons, Inc. C1 USN, Res Lab, Theoret Chem Sect, Washington, DC 20375 USA. RP Dunlap, BI (reprint author), USN, Res Lab, Theoret Chem Sect, Code 6179, Washington, DC 20375 USA. OI Dunlap, Brett/0000-0003-1356-6559 NR 48 TC 9 Z9 9 U1 0 U2 1 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD AUG 15 PY 1998 VL 69 IS 3 BP 317 EP 325 DI 10.1002/(SICI)1097-461X(1998)69:3<317::AID-QUA10>3.0.CO;2-# PG 9 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA 104GR UT WOS:000075006800009 ER PT J AU Koleske, DD Wickenden, AE Henry, RL DeSisto, WJ Gorman, RJ AF Koleske, DD Wickenden, AE Henry, RL DeSisto, WJ Gorman, RJ TI Growth model for GaN with comparison to structural, optical, and electrical properties SO JOURNAL OF APPLIED PHYSICS LA English DT Review ID CHEMICAL-VAPOR-DEPOSITION; MOLECULAR-BEAM EPITAXY; LIGHT-EMITTING DIODES; ALN BUFFER LAYER; POLYCRYSTALLINE DIAMOND FILMS; SURFACE-DIFFUSION LENGTH; LOW-PRESSURE MOVPE; PLUS ADSORBED BR; III-V NITRIDES; PHASE EPITAXY AB A kinetic model is presented to explain the metal organic vapor phase epitaxy (MOVPE) growth of GaN. The model is based upon measured desorption rates and assumptions on the precursor dissociation and sticking probabilities. The model shows how the growth temperature and V/III ratio are linked for the growth of high quality GaN films. From a comparison of growth conditions cited in the literature to the quality of GaN produced, optimal film growth appears to occur when the V/III ratio is chosen to be slightly larger than the N to Ga desorption ratio. The relationship between the growth temperature, V/III ratio, and GaN quality are explained in terms of how the growth parameters influence the incorporation of Ga and N atoms into the growing film. The Ga and N diffusion lengths are estimated to be 2-20 nm and <1 nm at 1050 degrees C, respectively, for practical MOVPE growth rates. Growth conditions for smooth (0001) surface morphology are described in terms of the growth model, as well as possible origins for defect incorporation in GaN. As a result of the large N desorption rate, it is suggested that during growth N is incorporated into the GaN lattice via an adsorption/desorption cycle. Application of the growth model to establishing the growth process conditions and run-to-run reproducibility are also discussed. [S0021-8979(98)01616-8]. C1 USN, Res Lab, Div Elect Sci & Technol, Lab Adv Mat Synth, Washington, DC 20375 USA. RP Koleske, DD (reprint author), USN, Res Lab, Div Elect Sci & Technol, Lab Adv Mat Synth, Code 6861, Washington, DC 20375 USA. EM koleske@estd.nrl.navy.mil NR 145 TC 104 Z9 108 U1 6 U2 52 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 AUG 15 PY 1998 VL 84 IS 4 BP 1998 EP 2010 DI 10.1063/1.368353 PG 13 WC Physics, Applied SC Physics GA 108GL UT WOS:000075257700039 ER PT J AU Jacobs, GA AF Jacobs, GA TI Sea surface height variations in the Yellow and east China Seas - 1. Linear response to local wind stress SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID ATMOSPHERIC PREDICTION SYSTEM; FORECAST MODEL; ALTIMETER DATA; KUROSHIO; NORTHEAST; NOGAPS; TAIWAN AB The sea surface height (SSH) variations observed by the TOPEX/POSEIDON satellite in the Yellow and East China Seas are examined over the 3 years from 1993 through 1995 assuming a linear response to wind stress across the region. The transfer function relating wind stress to SSH is modeled by a series of increasingly complex functions that gradually allow wind stress over successively broader regions and time periods to influence the SSH solution at a particular point. The SSH response to instantaneous wind stress at the same point in space implies an Ekman transport, but the response explains only a small fraction of the SSH variability. Relating SSH to wind stress averaged over two subregions and including both instantaneous and 12-hour lagged wind stress indicates that a significant portion of SSH variability responds to winds that are remote in both space and time. An optimal estimation of the transfer function by minimizing the error variance leads to an extended empirical orthogonal function (EEOF) analysis of the wind stress field. The SSH response to each wind mode is determined. The analysis shows the principle variations in the wind stress to consist of northerly wind bursts during winter, which produce large SSH drops in the Bohai Bay and northern Yellow Sea region. The principal wind mode also is significantly related to variations along the shelf break near the Kuroshio Current. The third and fourth wind stress modes indicate the passage of typhoons. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Jacobs, GA (reprint author), USN, Res Lab, Code 7323, Stennis Space Ctr, MS 39529 USA. RI Jacobs, Gregg/C-1456-2008 NR 29 TC 2 Z9 3 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 AUG 15 PY 1998 VL 103 IS C9 BP 18459 EP 18477 DI 10.1029/98JC01192 PG 19 WC Oceanography SC Oceanography GA 110CZ UT WOS:000075363700008 ER PT J AU Jacobs, GA Teague, WJ Riedlinger, SK Preller, RH Blaha, JP AF Jacobs, GA Teague, WJ Riedlinger, SK Preller, RH Blaha, JP TI Sea surface height variations in the Yellow and east China Seas - 2. SSH variability in the weekly and semiweekly bands SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID ATMOSPHERIC PREDICTION SYSTEM; FORECAST MODEL; NOGAPS AB Two types of models are used to examine the sea surface height (SSH) variability at the principle short time frequency bands in the Yellow and East China Seas. The models are a primitive equation numerical model and a statistical model based on TOPEX/POSEIDON altimeter data. In situ pressure gauge measurements at two mooring locations are first used to evaluate each model. In addition, a comparison of the numerical and statistical models is made through duplicate analysis of the response to the main extended empirical orthogonal function wind stress modes. In the northern Yellow Sea the wind stress, pressure gauge data, numerical model, and statistical model all indicate local spectral maxima in bands centered on the weekly and semiweekly periods. The coherence of the two models with the in situ data is significant down to 3-day periods at the northern mooring and down to 5-day periods at the southern mooring. The meridional wind stress variability in the semiweekly band is higher than the weekly band energy in the northern Yellow Sea and Bohai Bay and lower than the weekly band energy across the East China Sea. The SSH variability contained in the weekly and semiweekly bands is largest in the Bohai Bay and northern Yellow Sea with a region of high energy along the Chinese coast. The spatial structure of the weekly and semiweekly SSH variability is similar to the wind stress variability at these bands with semiweekly variability higher in the Bohai Bay and northern Yellow Sea and weekly variability dominant in the East China Sea. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. USN, Oceanog Off, Stennis Space Ctr, MS 39529 USA. RP Jacobs, GA (reprint author), USN, Res Lab, Code 7323, Stennis Space Ctr, MS 39529 USA. NR 15 TC 11 Z9 13 U1 0 U2 1 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 AUG 15 PY 1998 VL 103 IS C9 BP 18479 EP 18496 DI 10.1029/98JC01193 PG 18 WC Oceanography SC Oceanography GA 110CZ UT WOS:000075363700009 ER PT J AU Jansen, RW Shen, CY Chubb, SR Cooper, AL Evans, TE AF Jansen, RW Shen, CY Chubb, SR Cooper, AL Evans, TE TI Subsurface, surface, and radar modeling of a Gulf Stream current convergence SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID CAPE-HATTERAS; CONTINENTAL-SHELF; WATER; NORTH; WAVES; SIGNATURES; SLOPE AB In this paper we investigate the underlying dynamics associated with a strong, line-shaped submesoscale feature that was observed in radar imagery at the boundary between Gulf Stream (GS) and shelf water near Cape Hatteras during the first Naval Research Laboratory High-Resolution Remote Sensing Experiment (HIRES 1). The line-shaped feature, which appears as a pronounced (similar to 10 dB) increase in radar cross section, extends several kilometers in the east-west direction. In situ current measurements have shown that this feature coincides with the boundary of a sharp current convergence front. These measurements also indicate that the frontal dynamics is associated with the subduction of denser GS water under lighter shelf water. Using the observation that the convergence can be attributed to a hydrodynamic instability at the water interface, we have modeled the resulting subsurface hydrodynamics on the basis of a rigid-lid, two-dimensional solution of the Navier Stokes equation. The calculations of subsurface current flow were used as input to a spectral (wave action) model of wave-current interaction to obtain the surface wave field, which in turn was used to provide input for modeling of radar backscatter. The resulting description also includes the effects of surfactant-induced wave damping on electromagnetic backscatter. Our predictions are compared with real aperture radar imagery and in situ measurements from the HIRES 1 experiment. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP USN, Res Lab, Remote Sensing Div, Code 7252, Washington, DC 20375 USA. EM jansen@tsunami.nrl.navy.mil; shen@ccf.nrl.navy.mil; chubb@ccf.nrl.navy.mil; cooper5@nrlfs1.nrl.navy.mil; evans@argos.nrl.navy.mil NR 38 TC 19 Z9 19 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 AUG 15 PY 1998 VL 103 IS C9 BP 18723 EP 18743 DI 10.1029/98JC01195 PG 21 WC Oceanography SC Oceanography GA 110CZ UT WOS:000075363700024 ER PT J AU Lyzenga, DR Marmorino, GO AF Lyzenga, DR Marmorino, GO TI Measurement of surface currents using sequential synthetic aperture radar images of slick patterns near the edge of the Gulf Stream SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SEA; VELOCITIES AB Two-dimensional surface currents are estimated over an area of similar to 100 km(2) near the inshore edge of the Gulf Stream by correlating the surface slick patterns observed on two synthetic aperture radar (SAR) images collected about 20 min apart. The currents obtained from this analysis are found to agree well with shipboard acoustic Doppler current profiler (ADCP) measurements at 10 to 20-m depths. The orientations of the long, linear slicks observed in this region differ from the mean current direction by about 16 degrees but coincide with the direction of maximum radial deformation or strain, as calculated from the observed current field. The calculated current gradients indicate a mean surface convergence of about 2 x 10(-5) s(-1) and a cyclonic vorticity of about 1 x 10(-4) s(-1), values which fall within the range of previous estimates in the study area. These results suggest that slick patterns may be used to infer surface current magnitude and direction from a time sequence of SAR images but that care must be exercised in inferring current directions from the orientations of slick patterns within a single image. C1 Univ Michigan, Dept Naval Architecture & Marine Engn, Ann Arbor, MI 48109 USA. USN, Res Lab, Div Remote Sensing, Washington, DC 20375 USA. RP Lyzenga, DR (reprint author), Univ Michigan, Dept Naval Architecture & Marine Engn, Ann Arbor, MI 48109 USA. NR 22 TC 18 Z9 21 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 AUG 15 PY 1998 VL 103 IS C9 BP 18769 EP 18777 DI 10.1029/98JC00192 PG 9 WC Oceanography SC Oceanography GA 110CZ UT WOS:000075363700027 ER PT J AU Hwang, PA Walsh, EJ Krabill, WB Swift, RN Manizade, SS Scott, JF Earle, MD AF Hwang, PA Walsh, EJ Krabill, WB Swift, RN Manizade, SS Scott, JF Earle, MD TI Airborne remote sensing applications to coastal wave research SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SURFACE CONTOUR RADAR; GREENLAND ICE-SHEET; LASER ALTIMETRY; TRANSFORMATION; SPECTRA AB Airborne sensors provide effective coverage of a broad region and are suitable for large-scale experiments. In this paper, two scanning sensors that use the direct ranging technique to measure surface wave displacement are described. On a NASA P-3 aircraft the sensors can complete one run across a 100-km continental shelf in 17 min. A case study is presented using radar-measured, two-dimensional surface topography to derive wave damping due to bottom friction. The results are in good agreement with an analytical model based on a quadratic formulation of bottom shear stress. This study demonstrates that remote sensing measurements can be used for rapid characterization of surface waves on the continental shelf and in coastal regions. Examples illustrated in this paper include the derivation of wavenumber spectra and estimation of the dissipation rate of shoaling ocean swell. C1 USN, Res Lab, Div Oceanog, Stennis Space Ctr, MS 39529 USA. NASA, Lab Hydrosper Proc, Wallops Island, VA 23337 USA. EG&G Serv Inc, Wallops Flight Facil, Wallops Island, VA 23337 USA. Neptune Sci Inc, Reston, VA USA. RP Hwang, PA (reprint author), USN, Res Lab, Div Oceanog, Code 7332, Stennis Space Ctr, MS 39529 USA. NR 18 TC 14 Z9 14 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 AUG 15 PY 1998 VL 103 IS C9 BP 18791 EP 18800 DI 10.1029/98JC00895 PG 10 WC Oceanography SC Oceanography GA 110CZ UT WOS:000075363700029 ER PT J AU Paek, EG Choe, JY Oh, TK AF Paek, EG Choe, JY Oh, TK TI Transverse grating-assisted narrow-bandwidth acousto-optic tunable filter SO OPTICS LETTERS LA English DT Article ID WAVELENGTH AB An experimental acousto-optic tunable filter that has a narrow spectral bandwidth (0.2 nm at 1550 nm) and a fast (10-mu s) tuning capability with a continuous tuning range of approximately 50 nm is described. The tunable filter consists of an acousto-optic beam deflector with a diffraction grating whose grating vector is transverse to the direction of light propagation. C1 Natl Inst Stand & Technol, Informat Technol Lab, Gaithersburg, MD 20899 USA. USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Paek, EG (reprint author), Natl Inst Stand & Technol, Informat Technol Lab, Gaithersburg, MD 20899 USA. NR 11 TC 9 Z9 9 U1 0 U2 3 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 AUG 15 PY 1998 VL 23 IS 16 BP 1322 EP 1324 DI 10.1364/OL.23.001322 PG 3 WC Optics SC Optics GA 111GE UT WOS:000075428300026 PM 18087512 ER PT J AU Gole, JL Prokes, SM AF Gole, JL Prokes, SM TI Resonantly excited photoluminescence from porous silicon and the question of bulk phonon replicates SO PHYSICAL REVIEW B LA English DT Article ID OPTICAL-PROPERTIES; LUMINESCENCE MECHANISM; ANODIC-OXIDATION; SI NANOCRYSTALS; DEFECT CENTER; OXYGEN-ATOMS; BASIS-SETS; SURFACE; SPECTRA; CHEMISTRY AB High surface area porous silicon displays a light-induced visible photoluminescence (PL) in the 600-800-nm range, which has been associated with a variety of mechanisms, including emission from quantum confined silicon crystallites, surface-based states, surface confined defects, or molecular emitters. Key features used to support the quantum confinement hypothesis include the "phonon replicates," which, while observed only at very low temperatures have been interpreted as proof of a silicon phonon-assisted radiative process within the Si crystallites. For the quantum confinement model to be valid, only 2 or fewer of these "replicates" should be observed. We offer an alternate interpretation of the observed replicate features, which is not only consistent with the data presented by the quantum confinement proponents, but also is commensurate with the observation of additional structure by a number of researchers in the field. It is suggested that the observed "replicates" can be ascribed to transitions involving surface bound fluorophors that are associated with the silanone-based silicon oxyhydrides. Support for this interpretation is provided by quantum chemical calculations of the various silanone species as well as a variety of experimental observations. C1 Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. USN, Res Lab, Washington, DC 20375 USA. RP Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. NR 78 TC 19 Z9 19 U1 1 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 AUG 15 PY 1998 VL 58 IS 8 BP 4761 EP 4770 DI 10.1103/PhysRevB.58.4761 PG 10 WC Physics, Condensed Matter SC Physics GA 117GE UT WOS:000075772500083 ER PT J AU Woicik, JC Cross, JO Bouldin, CE Ravel, B Pellegrino, JG Steiner, B Bompadre, SG Sorensen, LB Miyano, KE Kirkland, JP AF Woicik, JC Cross, JO Bouldin, CE Ravel, B Pellegrino, JG Steiner, B Bompadre, SG Sorensen, LB Miyano, KE Kirkland, JP TI Diffraction anomalous fine-structure study of strained Ga1-xInxAs on GaAs(001) SO PHYSICAL REVIEW B LA English DT Article ID X-RAYS; SCATTERING; ALLOYS; HETEROSTRUCTURES; LAYERS AB Diffraction anomalous fine-structure measurements performed at both the Ga and As K edges have determined the Ga-As bond length to be 2.442+/-0.005 Angstrom in a buried, 213-Angstrom-thick Ga0.785In0.215As layer grown coherently on GaAs(001). This bond length corresponds to a strain-induced contraction of 0.013+/-0.005 Angstrom relative to the Ga-As bond length in bulk Ga1-xInxAs of the same composition. Together with recent extended x-ray-absorption fine-structure measurements performed at the In K edge [Woicik et al., Phys. Rev. Lett. 79, 5026 (1997)], excellent agreement is found with the uniform bond-length distortion model for strained-layer semiconductors on (001) substrates. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Washington, Dept Phys, Seattle, WA 98195 USA. CUNY Brooklyn Coll, Dept Phys, Brooklyn, NY 11210 USA. SFA Inc, Largo, MD 20774 USA. RP Woicik, JC (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 26 TC 20 Z9 20 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 AUG 15 PY 1998 VL 58 IS 8 BP R4215 EP R4218 DI 10.1103/PhysRevB.58.R4215 PG 4 WC Physics, Condensed Matter SC Physics GA 117GE UT WOS:000075772500006 ER PT J AU Hrabie, JA Srinivasan, A George, C Keefer, LK AF Hrabie, JA Srinivasan, A George, C Keefer, LK TI Reaction of nitric oxide with the imine double bond of certain Schiff bases SO TETRAHEDRON LETTERS LA English DT Article DE nitrogen oxides; imines; fragmentation reactions; diazenes AB Reaction of nitric oxide with N-benzylidene-4-methoxyaniline produced 4-methoxybenzenediazonium nitrate and benzaldehyde. This may represent an example of the electrophilic reaction of NO with a double bond. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 NCI, Chem Synth & Anal Lab, SAIC Frederick, Frederick Canc Res & Dev Ctr, Frederick, MD 21702 USA. NCI, Chem Sect, Comparat Carcinogenesis Lab, FCRDC, Frederick, MD 21702 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Hrabie, JA (reprint author), NCI, Chem Synth & Anal Lab, SAIC Frederick, Frederick Canc Res & Dev Ctr, Frederick, MD 21702 USA. RI Keefer, Larry/N-3247-2014 OI Keefer, Larry/0000-0001-7489-9555 NR 14 TC 19 Z9 19 U1 0 U2 0 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 AUG 13 PY 1998 VL 39 IS 33 BP 5933 EP 5936 DI 10.1016/S0040-4039(98)01218-0 PG 4 WC Chemistry, Organic SC Chemistry GA 104XF UT WOS:000075041200015 ER PT J AU Masumura, RA Hazzledine, PM Pande, CS AF Masumura, RA Hazzledine, PM Pande, CS TI Yield stress of fine grained materials SO ACTA MATERIALIA LA English DT Article ID HALL-PETCH RELATION; NANOCRYSTALLINE; COPPER; MICROHARDNESS; BEHAVIOR; DEFORMATION; DEPENDENCE; PALLADIUM; SIZE; FE AB A model is proposed for the yield stress of ultra-fine grained materials based upon Coble creep. Using Coble creep with a threshold stress for finer grains and conventional Hall-Fetch strengthening for larger grains, an analytical relation is derived for the yield stress as a function of grain size for a range from very large to very small. A grain size distribution is incorporated into the analysis to account for a distribution of grain sizes occurring in most specimens. This result is compared with experimental data from Cu and NiP and shown to be in good agreement. Acta Metallurgica Inc. Published by Elsevier Science Ltd. C1 USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. USAF, Wright Lab, Mat Directorate, MLLM, Wright Patterson AFB, OH 45433 USA. RP Masumura, RA (reprint author), USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. NR 34 TC 286 Z9 303 U1 2 U2 69 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD AUG 10 PY 1998 VL 46 IS 13 BP 4527 EP 4534 DI 10.1016/S1359-6454(98)00150-5 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 112KN UT WOS:000075494000007 ER PT J AU Frankel, MY Esman, RD AF Frankel, MY Esman, RD TI Dynamic null steering in an ultrawideband time-steered array antenna SO APPLIED OPTICS LA English DT Article AB We develop a method for forming squint-free wideband nulls in the antenna pattern of an ultrawideband array antenna. The technique uses an optical dispersive-prism beam former to provide time-delayed microwave signals to each antenna element for forming a squint-free main bean. The amplitude-modulated optical carrier is propagated through a set of optical Links. Each link feeds an array element and includes an amount of dispersion proportional to element position. Tuning the wavelength of the optical carrier controls the microwave signal's arrival-time delay gradient across the array. A dispersive-prism tapped delay-line microwave filter is used to frequency shape a nulling signal. The wideband nulls do not significantly distort the main beam and are steered independently of the main beam. The technique is applied to sidelobe nulling for a transmitter and for jammer suppression for a receiver array. (C) 1998 Optical Society of America. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Frankel, MY (reprint author), Ciena Corp, 920 Elkridge Landing Rd, Linthicum, MD 21090 USA. NR 11 TC 9 Z9 9 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 AUG 10 PY 1998 VL 37 IS 23 BP 5488 EP 5494 DI 10.1364/AO.37.005488 PG 7 WC Optics SC Optics GA 109AK UT WOS:000075298900018 PM 18286034 ER PT J AU Vurgaftman, I Meyer, JR Julien, FH Ram-Mohan, LR AF Vurgaftman, I Meyer, JR Julien, FH Ram-Mohan, LR TI Design and simulation of low-threshold antimonide intersubband lasers SO APPLIED PHYSICS LETTERS LA English DT Article ID QUANTUM-WELLS AB Optically and electrically pumped infrared lasers based on intersubband transitions in InAs/GaSb/AlsSb quantum wells are modeled in detail. The large conduction-band offset of the AlAsSb barriers with respect to the InAs wells allows the lasing wavelength to be shortened to at least 1.9 mu m. Furthermore, the small InAs electron mass results in longer phonon-limited lifetimes in the upper lasing subband as well as larger dipole matrix elements. This leads to the prediction of lower threshold currents, and hence, higher cw operating temperatures than for quantum cascade lasers based on the InCaAs/InAlAs/InP system. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Paris Sud, URA CNRS 22, Inst Elect Fondamentale, F-91405 Orsay, France. Worcester Polytech Inst, Worcester, MA 01609 USA. RP Vurgaftman, I (reprint author), USN, Res Lab, Code 5613, Washington, DC 20375 USA. RI Ram-Mohan, Ramdas/C-5167-2012 NR 14 TC 62 Z9 63 U1 1 U2 5 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 AUG 10 PY 1998 VL 73 IS 6 BP 711 EP 713 DI 10.1063/1.121976 PG 3 WC Physics, Applied SC Physics GA 109CJ UT WOS:000075303400003 ER PT J AU Levine, SE Sparke, LS AF Levine, SE Sparke, LS TI The stability of "perfect elliptic disks." II. A minimal streaming case SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : elliptical and lenticular, cD; galaxies : kinematics and dynamics; galaxies : structure; methods : numerical ID NONROTATING STELLAR-SYSTEMS; SHELL-ORBIT MODELS; GALAXY SIMULATIONS; INSTABILITIES; EQUILIBRIUM; DYNAMICS AB Two-dimensional realizations of self-consistent models for the "perfect elliptic disks" were tested for global stability by gravitational N-body integration. The family, of perfect elliptic disk potentials have two isolating integrals; time-independent distribution functions f(E, I(2)), which self-consistently reproduce the density distribution, can be found numerically, using a modified marching scheme to compute the relative contributions of each member in a library of orbits. The possible solutions are not unique; for a given ellipticity, the models can have a range of angular momenta. Here results are presented for cases with minimal angular momentum, hence maximal random motion. As in previous work, N-body realizations were constructed using a modified quiet start technique to place particles on these orbits uniformly in action-angle space, making the initial conditions as smooth as possible. The most elliptical models initially showed bending instabilities; by the end of the run they had become slightly rounder. The most nearly axisymmetric models tended to become more elongated, reminiscent of the radial orbit instability in spherical systems. Between these extremes, there is a range of axial ratios 0.305 less than or similar to b/a less than or similar to 0.570 for which the minimum streaming models appear to be stable. C1 Univ Nacl Autonoma Mexico, IA, Observ Astron Nacl, Ensenada, Baja California, Mexico. Univ Wisconsin, Washburn Observ, Madison, WI 53706 USA. RP Levine, SE (reprint author), USN Observ, Flagstaff Stn, POB 1149, Flagstaff, AZ 86002 USA. NR 39 TC 4 Z9 4 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 AUG 10 PY 1998 VL 503 IS 1 BP 125 EP 137 DI 10.1086/305985 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KK UT WOS:000077776400011 ER PT J AU Hix, WR Khokhlov, AM Wheeler, JC Thielemann, FK AF Hix, WR Khokhlov, AM Wheeler, JC Thielemann, FK TI The quasi-equilibrium-reduced alpha-network SO ASTROPHYSICAL JOURNAL LA English DT Article DE methods : numerical; nuclear reactions, nucleosynthesis, abundances; stars : evolution; supernovae : general ID SILICON AB An examination of the process of silicon burning, the burning stage that leads to the production of the iron peak nuclei, reveals that the nuclear evolution is dominated by large groups of nuclei in mutual equilibrium. These quasi-equilibrium (QSE) groups form well in advance of the global nuclear statistical equilibrium (NSE). We present an improved "minimal" nuclear network, which takes advantage of QSE in order to calculate the nuclear evolution and energy generation while further reducing the computational cost compared with a conventional alpha-chain network. During silicon burning the resultant QSE-reduced alpha-network is twice as fast as the full alpha-network it replaces and requires the tracking of only half as many abundance variables, without significant loss of accuracy. When the QSE-reduced alpha-network is used in combination with a conventional alpha-network stretching from He to Si, the combined network, which we call the alpha 7 network, provides an accurate approximation for all of the burning stages from He burning to NSE, while tracking only seven abundances. These reductions in computational cost and the number of species evolved make the alpha 7 network well suited for inclusion within hydrodynamic simulations, particularly those in multidimension. C1 Univ Texas, Dept Astron, Austin, TX 78712 USA. Naval Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC USA. Univ Basel, Dept Phys & Astron, CH-4056 Basel, Switzerland. RP Hix, WR (reprint author), Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. RI Hix, William/E-7896-2011 OI Hix, William/0000-0002-9481-9126 NR 12 TC 25 Z9 25 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 AUG 10 PY 1998 VL 503 IS 1 BP 332 EP 343 DI 10.1086/305968 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KK UT WOS:000077776400028 ER PT J AU Feldman, U Curdt, W Doschek, GA Schuhle, U Wilhelm, K Lemaire, P AF Feldman, U Curdt, W Doschek, GA Schuhle, U Wilhelm, K Lemaire, P TI High-temperature lines in SUMER spectra recorded above a bright solar active region SO ASTROPHYSICAL JOURNAL LA English DT Article DE line : identifications; Sun : corona; Sun : UV radiation ID EXPERIMENTAL LEVEL VALUES; ISOELECTRONIC SEQUENCE; FORBIDDEN LINES; SPECTROMETER; CONFIGURATIONS; SOHO; DIAGNOSTICS; TELESCOPE; IONS AB We identify spectral lines emitted by solar abundant elements due primarily to transitions within the 2s(2)2p(k) and 3s(2)3p(k) (where k = 1, 5) ground configurations of ions that are formed in ionization equilibrium between 2 x 10(6) and 8 x 10(6) K. The transitions were identified in spectra of a bright active region recorded 1997 September 6, by the Solar Ultraviolet Measurements of Emitted Radiation Spectrometer (SUMER) flown on the Solar and Heliospheric Observatory (SOHO). Some of these lines provide useful plasma diagnostic tools for measuring the physical conditions in the solar corona. 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, Inst Astrophys Spatiale, Unite Mixte Ctr Natl Res Sci, F-91405 Orsay, France. 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 25 TC 25 Z9 25 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 AUG 10 PY 1998 VL 503 IS 1 BP 467 EP 474 DI 10.1086/305966 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KK UT WOS:000077776400044 ER PT J AU Schumer, JW Holloway, JP AF Schumer, JW Holloway, JP TI Vlasov simulations using velocity-scaled hermite representations SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE Vlasov solvers; spectral methods ID PLASMA; EQUATIONS; SPACE; TIME AB The efficiency, accuracy, and stability of two different pseudo-spectral methods using scaled Hermite basis and weight functions, applied to the nonlinear Vlasov-Poisson equations in one dimension (1d-1v), are explored and compared. A variable velocity scale U is introduced into the Hermite basis and is shown to yield orders of magnitude reduction in errors, as compared to Linear kinetic theory, with no increase in workload, A set of Fourier-Hermite coefficients, representing a periodic Gaussian distribution function, are advanced through time with an O(Delta t(2))-accurate splitting method, Within this splitting scheme, the advection and acceleration terms of the Vlasov equation are solved separately using an O (all)-accurate Runge-Kutta method. The asymmetrically weighted (AW) Hermite basis, which has been used previously by many authors, conserves particles and momentum exactly and total energy to O (Delta t(3)); however, the AW Hermite method does not conserve the square integral of the distribution and is, in fact, numerically unstable. The symmetrically weighted (SW) Hermite algorithm, applied here to the Vlasov system for the first time, can either conserve particles and energy (for N-u even) or momentum (for N-u odd) as Delta t --> 0, where N, is the largest Hermite mode number. The SW Hermite method conserves the square integral of the distribution and, therefore, remains numerically stable. In addition, careful velocity scaling improves the conservation properties of the SW Hermite method. Damping and growth rates, oscillation frequencies, E-field saturation levels, and phase-space evolution are seen to be qualitatively correct during simulations. Relative errors with respect to linear Landau damping and linear bump-on-tail instability are shown to be less than 1% using only 64 velocity-scaled Hermite functions. Comparisons to particle-in-cell (PIC) simulations show that as the number of particles increases to more than 10(6), the PIC solutions converge to scaled SW Hermite solutions that were found in only 1/10 of the run-time. The SW Hermite method with velocity scaling is weil-suited to kinetic simulations of warm plasmas. (C) 1998 Academic Press. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Michigan, Ann Arbor, MI 48109 USA. RP Schumer, JW (reprint author), USN, Res Lab, Code 6770, Washington, DC 20375 USA. RI Schumer, Joseph/D-7591-2013 NR 33 TC 37 Z9 37 U1 3 U2 7 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 AUG 10 PY 1998 VL 144 IS 2 BP 626 EP 661 DI 10.1006/jcph.1998.5925 PG 36 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 110MX UT WOS:000075385900015 ER PT J AU Banin, U Lee, CJ Guzelian, AA Kadavanich, AV Alivisatos, AP Jaskolski, W Bryant, GW Efros, AL Rosen, M AF Banin, U Lee, CJ Guzelian, AA Kadavanich, AV Alivisatos, AP Jaskolski, W Bryant, GW Efros, AL Rosen, M TI Size-dependent electronic level structure of InAs nanocrystal quantum dots: Test of multiband effective mass theory SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article AB The size dependence of the electronic spectrum of InAs nanocrystals ranging in radius from 10-35 Angstrom has been studied by size-selective spectroscopy. An eight-band effective mass theory of the quantum size levels has been developed which describes the observed absorption level structure and transition intensities very well down to smallest crystal size using bulk band parameters. This model generalizes the six-band model which works well in CdSe nanocrystals and should adequately describe most direct semiconductor nanocrystals with band edge at the Gamma-point of the Brillouin zone. (C) 1998 American Institute of Physics. C1 Inst Fizyki UMK, Torun, Poland. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. USN, Res Lab, Nanostruct Opt Sect, Washington, DC 20375 USA. RP Banin, U (reprint author), Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. RI Jaskolski, Wlodzimierz/D-1318-2014; Alivisatos , Paul /N-8863-2015 OI Jaskolski, Wlodzimierz/0000-0003-4814-1876; Alivisatos , Paul /0000-0001-6895-9048 NR 16 TC 133 Z9 133 U1 0 U2 26 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 AUG 8 PY 1998 VL 109 IS 6 BP 2306 EP 2309 DI 10.1063/1.476797 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 107XW UT WOS:000075237100032 ER PT J AU Buttrey, SE AF Buttrey, SE TI Nearest-neighbor classification with categorical variables SO COMPUTATIONAL STATISTICS & DATA ANALYSIS LA English DT Article DE optimal scaling; cross-validation; Fisher's criterion; choice of metric ID TRANSFORMATIONS AB A technique is presented for adopting nearest-neighbor classification to the case of categorical variables. The set of categories is mapped onto the real line in such a way as to maximize the ratio of total sum of squares to within-class sum of squares, aggregated over classes. The resulting real values then replace the categories, and nearest-neighbor classification proceeds with the Euclidean metric on these new values. Continuous variables can be included in this scheme with little added efort. This approach has been implemented in a computer program and tried on a number of data sets, with encouraging results. Nearest-neighbor classification is a well-known and efective classification technique. With this scheme, an unknown item's distances to all known items are measured, and the unknown class is estimated by the class of the nearest neighbor or by the class most often represented among a set of nearest neighbors. This has proven effective in many examples, but an appropriate distance normalization is required when variables are scaled differently. For categorical variables "distance" is not even defined. In this paper categorical data values are replaced by real numbers in an optimal way: then those real numbers are used in nearest-neighbor classification (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Postgrad Sch, Dept Operat Res Sb, Monterey, CA 93943 USA. EM buttrey@nps.navy.mil NR 16 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9473 J9 COMPUT STAT DATA AN JI Comput. Stat. Data Anal. PD AUG 7 PY 1998 VL 28 IS 2 BP 157 EP 169 DI 10.1016/S0167-9473(98)00032-2 PG 13 WC Computer Science, Interdisciplinary Applications; Statistics & Probability SC Computer Science; Mathematics GA 114VZ UT WOS:000075631000003 ER PT J AU Aifer, EH Bewley, WW Felix, CL Vurgaftman, I Olafsen, LJ Meyer, JR Lee, H Martinelli, RU Connolly, JC Sugg, AR Olsen, G AF Aifer, EH Bewley, WW Felix, CL Vurgaftman, I Olafsen, LJ Meyer, JR Lee, H Martinelli, RU Connolly, JC Sugg, AR Olsen, G TI CW operation of 3.4 mu m optically-pumped type-II W laser to 220K SO ELECTRONICS LETTERS LA English DT Article ID DIODE-LASERS AB An optically-pumped type-Il W laser emitting at 3.4 mu m operated CW up to 220 K, with a characteristic temperature of 51 K for the range 78-220 K. At 78 K, the output power was 90 mW from a 12 mu m wide stripe, and the differential power conversion efficiency was 2.9% per facet (uncoated). C1 USN, Res Lab, Washington, DC 20375 USA. Sarnoff Corp, Princeton, NJ USA. Sensors Unlimited, Princeton, NJ USA. RP Aifer, EH (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Olafsen, Linda/G-4996-2013 NR 11 TC 8 Z9 9 U1 0 U2 2 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 AUG 6 PY 1998 VL 34 IS 16 BP 1587 EP 1588 DI 10.1049/el:19981136 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 113LA UT WOS:000075551400038 ER PT J AU Shlesinger, MF AF Shlesinger, MF TI Dynamics of complex systems SO NATURE LA English DT Book Review C1 Off Naval Res, Phys Sci Div 331, Arlington, VA 22217 USA. RP Shlesinger, MF (reprint author), Off Naval Res, Phys Sci Div 331, 800 N Quincy St, Arlington, VA 22217 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD AUG 6 PY 1998 VL 394 IS 6693 BP 538 EP 538 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 107YN UT WOS:000075238700035 ER PT J AU Shlesinger, MF AF Shlesinger, MF TI Chaos theory tamed SO NATURE LA English DT Book Review C1 Off Naval Res, Phys Sci Div 331, Arlington, VA 22217 USA. RP Shlesinger, MF (reprint author), Off Naval Res, Phys Sci Div 331, 800 N Quincy St, Arlington, VA 22217 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD AUG 6 PY 1998 VL 394 IS 6693 BP 538 EP 538 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 107YN UT WOS:000075238700034 ER PT J AU Krowne, CM AF Krowne, CM TI Marginal nonreciprocity in linear bi-isotropic media SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE bi-isotropic media; electromagnetic behavior; nonreciprocity and reciprocity ID ANISOTROPIC MEDIA AB We examine die implications for Tellegen behavior of the classical electromagnetic fields by providing a derivation showing that nonreciprocity is not to be expected in ordinary chiral-like or bi-isotropic media. Nonreciprocal behavior will only be attained by combining the basically reciprocal chiral or bi-isotropic materials with known nonreciprocating media. (C) 1998 John Wiley & Sons, Inc. C1 USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Washington, DC 20375 USA. RP Krowne, CM (reprint author), USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Code 6850-3, Washington, DC 20375 USA. NR 18 TC 2 Z9 2 U1 0 U2 1 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 AUG 5 PY 1998 VL 18 IS 5 BP 356 EP 359 DI 10.1002/(SICI)1098-2760(19980805)18:5<356::AID-MOP15>3.0.CO;2-0 PG 4 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA 101PG UT WOS:000074876900014 ER PT J AU Fatemi, M Wickenden, AE Koleske, DD Twigg, ME Freitas, JA Henry, RL Gorman, RJ AF Fatemi, M Wickenden, AE Koleske, DD Twigg, ME Freitas, JA Henry, RL Gorman, RJ TI Enhancement of electrical and structural properties of GaN layers grown on vicinal-cut, a-plane sapphire substrates SO APPLIED PHYSICS LETTERS LA English DT Article ID SILICON; FILMS AB We report the observation of significant enhancement in the electrical and crystalline properties of GaN layers grown on vicinally cut, a-plane sapphire substrates. Room-temperature Hall mobility and x-ray rocking curve data show a nearly twofold improvement, independent of the processing conditions, for layers grown on substrates having vicinal angles of 1.5 degrees compared to on-axis substrates. Transmission electron microscopy shows reduced edge dislocation density and better alignment of the grains in layers grown on vicinally cut substrates. Preliminary photoluminescence measurements also indicate pronounced differences in the yellow band spectra between the on-axis and off-axis cut substrates. These findings contrast the relatively modest improvements observed in layers grown on c-plane substrates with vicinal angles as high as 10 degrees. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RP Fatemi, M (reprint author), USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. EM fatemi@estd.nrl.navy.mil NR 14 TC 32 Z9 32 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 AUG 3 PY 1998 VL 73 IS 5 BP 608 EP 610 DI 10.1063/1.121871 PG 3 WC Physics, Applied SC Physics GA 108CV UT WOS:000075249200018 ER PT J AU Henderson, DR AF Henderson, DR TI The Commanding Heights SO FORTUNE LA English DT Book Review C1 Hoover Inst, Stanford, CA 94305 USA. USN, Postgrad Sch, Monterey, CA USA. RP Henderson, DR (reprint author), Hoover Inst, Stanford, CA 94305 USA. NR 1 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 AUG 3 PY 1998 VL 138 IS 3 BP 48 EP + PG 2 WC Business SC Business & Economics GA 100FX UT WOS:000074806400017 ER PT J AU Burgher, SW Tandy, TK Dawdy, MR AF Burgher, SW Tandy, TK Dawdy, MR TI Transvaginal ultrasonography by emergency physicians decreases patient time in the emergency department SO ACADEMIC EMERGENCY MEDICINE LA English DT Article; Proceedings Paper CT SAEM Annual Meeting CY MAY, 1997 CL WASHINGTON, D.C. SP SAEM DE ultrasonography; pregnancy, ectopic; pregnancy, tubal; pregnancy trimester, first; emergency medicine ID ECTOPIC PREGNANCY; RISK; ULTRASOUND; SONOGRAPHY; DIAGNOSIS AB Objectives: An important argument for emergency physician use of ultrasonography is that it results in more rapid patient disposition, but there are few articles to support this position. This study sought to demonstrate a significant decrease in the time spent in the ED when emergency physicians performed transvaginal ultrasonography (TVUS), as compared with when TVUS was performed by consultants, in the evaluation of first-trimester pelvic pain or vaginal bleeding. Methods: A retrospective analysis was conducted of the time spent in the ED (time placed in gynecologic examination room to time released from ED) by patients with first-trimester pelvic pain or vaginal bleeding necessitating further evaluation with TVUS. TVUS was performed in the ED by obstetrics/gynecology (ob/gyn) residents who were consulted to the ED from January 11, 1996, to March 31, 1996, and by emergency physicians from April 17, 1996, to July 7, 1996. Results: Emergency physicians evaluated 46 patients by TVUS, with a mean time of 164.70 minutes (SEM +/- 13.29). Ob/gyn consultants evaluated 38 patients by TVUS, with a mean time of 234.79 minutes (SEM +/- 12.74). This was a significant difference at the level of p < 0.0003 (Student's t-test). There were no known missed ectopic pregnancies as ascertained by 100% patient follow-up. There was no significant difference between the groups in the percentage of ectopic pregnancies (Fisher's exact test). The number of patients in the emergency physician group requiring subsequent consultation was reduced by 85%. Conclusions: This study demonstrates a more rapid ED transit time when TVUS was performed at the bedside by emergency physicians as compared with when pelvic ultrasonography required consultation. Additionally, fewer calls to consultants were required. C1 USN, Med Ctr Portsmouth, Dept Emergency Med, Portsmouth, VA 23708 USA. RP Burgher, SW (reprint author), USN, Med Ctr Portsmouth, Dept Emergency Med, Bldg 215,620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 20 TC 37 Z9 37 U1 1 U2 1 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 AUG PY 1998 VL 5 IS 8 BP 802 EP 807 PG 6 WC Emergency Medicine SC Emergency Medicine GA 109VR UT WOS:000075345100009 PM 9715242 ER PT J AU Holmboe, E Scranton, R Sumption, K Hawkins, R AF Holmboe, E Scranton, R Sumption, K Hawkins, R TI Effect of medical record audit and feedback on residents' compliance with preventive health care guidelines SO ACADEMIC MEDICINE LA English DT Article ID OUTPATIENT AB Purpose. To examine the effect on residents' compliance with preventive health guidelines of an intensive quality improvement program using medical record audits and individualized feedback. Method. The before-and-after study was set in a general internal medicine clinic at a military teaching hospital. In 1995, the authors retrospectively reviewed 280 medical records to determine whether, after the hospital had started an audit-and-feedback program in 1994, residents' compliance rates had risen for preventive health interventions. The study looked at both audited and non-audited interventions. Results. The residents' compliance rates significantly im proved for the audited interventions (tetanus immunization, breast examination, and rectal examination). They also had higher compliance rates for six of the seven non-audited interventions. Conclusions. An intensive medical record audit with individualized feedback can produce exceptionally high levels of compliance with preventive care practices among internal medicine residents. Furthermore, the improved compliance is generalizable to other health care measures not directly targeted for audit. C1 Yale Univ, Sch Med, Robert Wood Johnson Clin Scholars Program, New Haven, CT 06520 USA. USN, Med Ctr, Dept Internal Med, Portsmouth, VA USA. Uniformed Serv Univ Hlth Sci, F Edward Hebert Sch Med, Dept Internal Med, Bethesda, MD 20814 USA. RP Holmboe, E (reprint author), Yale Univ, Sch Med, Robert Wood Johnson Clin Scholars Program, IE-61 SHM,POB 208025, New Haven, CT 06520 USA. NR 6 TC 30 Z9 30 U1 0 U2 0 PU HANLEY & BELFUS INC PI PHILADELPHIA PA 210 S 13TH ST, PHILADELPHIA, PA 19107 USA SN 1040-2446 J9 ACAD MED JI Acad. Med. PD AUG PY 1998 VL 73 IS 8 BP 901 EP 903 DI 10.1097/00001888-199808000-00016 PG 3 WC Education, Scientific Disciplines; Health Care Sciences & Services SC Education & Educational Research; Health Care Sciences & Services GA 111AG UT WOS:000075414700020 PM 9736851 ER PT J AU Lawson, BD Mead, AM AF Lawson, BD Mead, AM TI The sopite syndrome revisited: Drowsiness and mood changes during real or apparent motion SO ACTA ASTRONAUTICA LA English DT Article ID SICKNESS; FATIGUE; CREWS AB The sopite syndrome is a poorly understood response to motion. Drowsiness and mood changes are the primary characteristics of the syndrome. The sopite syndrome can exist in isolation from more apparent symptoms such as nausea, can last long after nausea has subsided, and can debilitate some individuals. It is most likely a distinct syndrome from "regular" motion sickness or common fatigue, and is of potential concern in a variety of situations. The syndrome may be particularly hazardous in transportation settings where other performance challenges (e.g., sleep deprivation) are already present. It is also a potential concern in cases where illnesses such as sleep disorders or depression may interact with the syndrome and confuse diagnosis. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 USN, Aerosp Med Res Lab, Pensacola, FL 32508 USA. RP Lawson, BD (reprint author), USN, Aerosp Med Res Lab, 51 Hovey Rd, Pensacola, FL 32508 USA. FU NCI NIH HHS [CB701] NR 59 TC 31 Z9 31 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD AUG-SEP PY 1998 VL 43 IS 3-6 BP 181 EP 192 DI 10.1016/S0094-5765(98)00153-2 PG 12 WC Engineering, Aerospace SC Engineering GA 121CE UT WOS:000075993900010 PM 11541923 ER PT J AU Limjoco, UR Grubbs, JM Thomas, MD AF Limjoco, UR Grubbs, JM Thomas, MD TI Richter's hernia with bowel perforation SO AMERICAN FAMILY PHYSICIAN LA English DT Letter C1 USN Hosp, Marine Corps Air Ground Combat Ctr, Twentynine Palms, CA 92278 USA. RP Limjoco, UR (reprint author), USN Hosp, Marine Corps Air Ground Combat Ctr, Box 788250, Twentynine Palms, CA 92278 USA. NR 4 TC 1 Z9 2 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 AUG PY 1998 VL 58 IS 2 BP 352 EP + PG 2 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 107WP UT WOS:000075234200005 PM 9713392 ER PT J AU Schneider, CS Ertel, JP AF Schneider, CS Ertel, JP TI A classroom jumping ring SO AMERICAN JOURNAL OF PHYSICS LA English DT Article AB We present the design of a compact alternating current jumping ring apparatus which can electromagnetically launch conducting rings across a classroom. Jump energy and height are calculated for core and thin ring length, radius, thickness, and material. The effects of core saturation, permeability, hysteresis and demagnetizing field, ring shielding, and convective derivative are described. Rings with even small phase lag can pass by the magnetic pole of the primary in one-quarter of a cycle. Large ring size relative to skin depth delays the ring current close to the 180 deg of Lent's law. Contactless jump height measurement enables ring resistivity determination. Demonstrating the effects of voltage, frequency, conductivity, permeability, and geometry contributes to understanding electromagnetism in the classroom. (C) 1998 American Association of Physics Teachers. C1 USN Acad, Dept Phys, Annapolis, MD 21402 USA. RP Schneider, CS (reprint author), USN Acad, Dept Phys, Annapolis, MD 21402 USA. NR 12 TC 10 Z9 10 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD AUG PY 1998 VL 66 IS 8 BP 686 EP 692 DI 10.1119/1.18933 PG 7 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 103GD UT WOS:000075148800016 ER PT J AU Yavorski, CC Greason, KL Egan, MC AF Yavorski, CC Greason, KL Egan, MC TI Splenic cysts: A new approach to partial splenectomy case report and review of the literature SO AMERICAN SURGEON LA English DT Article ID SPLEEN; MANAGEMENT AB Cysts of the spleen are rare entities and can be classified as either primary or secondary depending on the presence of a true epithelial lining. We report such a case in a young woman who presented with a symptomatic primary splenic cyst that was located in the lower pole of the spleen. We performed a partial splenectomy using a TA-90 stapler. The stapler provided excellent hemostasis and represents a convenient and safe technique for a resection. We recommend employment of this technique when faced with a similar ease. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Gen Surg, San Diego, CA 92134 USA. Univ Kentucky, Dept Surg, Div Vasc Surg, Lexington, KY USA. RP Yavorski, CC (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 11 TC 10 Z9 14 U1 0 U2 0 PU SOUTHEASTERN SURGICAL CONGRESS PI ATLANTA PA 141 WEST WIEUCA RD, STE B100, ATLANTA, GA 30342 USA SN 0003-1348 J9 AM SURGEON JI Am. Surg. PD AUG PY 1998 VL 64 IS 8 BP 795 EP 798 PG 4 WC Surgery SC Surgery GA 104ND UT WOS:000075019900030 PM 9697917 ER PT J AU Soni, MH Callahan, JH McElvany, SW AF Soni, MH Callahan, JH McElvany, SW TI Laser desorption - Membrane introduction mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID VOLATILE ORGANIC-COMPOUNDS; FLOW-INJECTION ANALYSIS; PER-TRILLION LEVELS; AROMATIC-HYDROCARBONS; ION-SOURCE; ONLINE; INLET; WATER; AIR; INTERFACE AB In this paper we describe the first use of laser desorption in conjunction with membrane introduction mass spectrometry (MIMS). In this technique, a low-powered carbon dioxide laser is used to irradiate the low-pressure (vacuum) side of a silicone membrane during a typical MIMS analysis of an aqueous solution. The absorption of laser energy results in direct membrane heating and rapid desorption of permeate molecules. This improves both the sensitivity and response times of MIMS when analyzing compounds having high molecular weight and low volatility. Two simple interfaces are described for performing laser desorption inside and outside the vacuum manifold of a GCQ ion trap mass spectrometer. Together with now injection (FI) sample introduction, we demonstrate direct on-line monitoring of;aqueous Solutions of high boding point (200-530 degrees C) polynuclear aromatic hydrocarbons such as naphthalene, anthracene, pyrene, benzo[b]fluoranthene, and indeno[123-cd]pyrene. C1 USN, Res Lab, Analyt Chem Sect, Washington, DC 20375 USA. RP USN, Res Lab, Analyt Chem Sect, Code 6113, Washington, DC 20375 USA. NR 53 TC 41 Z9 41 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 EI 1520-6882 J9 ANAL CHEM JI Anal. Chem. PD AUG 1 PY 1998 VL 70 IS 15 BP 3103 EP 3113 DI 10.1021/ac980436l PG 11 WC Chemistry, Analytical SC Chemistry GA 107VQ UT WOS:000075232000011 PM 21644650 ER PT J AU Lodha, GS Yamashita, K Kunieda, H Tawara, Y Yu, J Namba, Y Bennett, JM AF Lodha, GS Yamashita, K Kunieda, H Tawara, Y Yu, J Namba, Y Bennett, JM TI Effect of surface roughness and subsurface damage on grazing-incidence x-ray scattering and specular reflectance SO APPLIED OPTICS LA English DT Article ID OPTICAL-CONSTANTS; ALUMINUM FILMS; REFLECTIVITY; MIRRORS AB Grazing-incidence specular reflectance and near-specular scattering were measured at AI-K, (1.486-keV, 8.34-Angstrom) radiation an uncoated dielectric substrates whose surface topography had been measured with a scanning probe microscope and a mechanical profiler. Grazing-incidence specular reflectance was also measured on selected substrates at the Cu-K-alpha (8.047-keV, 1.54-Angstrom) wavelength. Substrates included superpolished and conventionally polished fused silica; SiO2 wafers; superpolished and precision-ground Zerodur; conventionally polished, float-polished, and precision-ground BK-7 glass; and superpolished and precision-ground silicon carbide. Roughnesses derived from x-ray specular reflectance and scattering measurements mere in good agreement with topographic roughness values measured with a scanning probe microscope (atomic force microscope) and a mechanical profiler that included similar ranges of surface spatial wavelengths. The specular reflectance was also found to be sensitive to the density of polished surface layers and subsurface damage down to the penetration depth of the x rays. Density gradients and subsurface damage were found in the superpolished fused-silica and precision-ground Zerodur samples. These results suggest that one can nondestructively evaluate subsurface damage in transparent materials using grazing-incidence x-ray specular reflectance in the 1.5-8-keV range. (C) 1998 Optical Society of America. C1 Nagoya Univ, Dept Phys, Chikusa Ku, Nagoya, Aichi 46401, Japan. Chubu Univ, Dept Mech Engn, Kasugai, Aichi 487, Japan. USN, Air Warfare Ctr, China Lake, CA 93555 USA. RP Lodha, GS (reprint author), Ctr Adv Technol, Indore 452013, India. NR 27 TC 21 Z9 22 U1 1 U2 10 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 AUG 1 PY 1998 VL 37 IS 22 BP 5239 EP 5252 DI 10.1364/AO.37.005239 PG 14 WC Optics SC Optics GA 106AJ UT WOS:000075107300030 PM 18286003 ER PT J AU Aglitskiy, Y Lehecka, T Obenschain, S Bodner, S Pawley, C Gerber, K Sethian, J Brown, CM Seely, J Feldman, U Holland, G AF Aglitskiy, Y Lehecka, T Obenschain, S Bodner, S Pawley, C Gerber, K Sethian, J Brown, CM Seely, J Feldman, U Holland, G TI High-resolution monochromatic x-ray imaging system based on spherically bent crystals SO APPLIED OPTICS LA English DT Article ID DENSITY PLASMA DIAGNOSTICS; LASER-PRODUCED PLASMAS; RADIOGRAPHY; FOILS; SPECTROSCOPY; IRRADIATION; INCOHERENCE; EMISSION; PROFILES; TARGETS AB We have developed an improved x-ray imaging system based on spherically curved crystals. It is designed and used for diagnostics of targets ablatively accelerated by the Nike KrF laser. A spherically curved quartz crystal (2d = 6.687 Angstrom, R = 200 mm) has been used to produce monochromatic backlit images with the He-like Si resonance line (1865 eV) as the source of radiation. The spatial resolution of the x-ray optical system is 1.7 mu m in selected places and 2-3 mu m over a larger area. Time-resolved backlit monochromatic images of polystyrene planar targets driven by the Nike facility have been obtained with a spatial resolution of 2.5 mu m in selected places and 5 mu m over the focal spot of the Nike laser. (C) 1998 Optical Society of America. C1 Sci Applicat Int Corp, Mclean, VA 22102 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. USN, Res Lab, Div Space Sci, Washington, DC 20375 USA. SFA Inc, Landover, MD 20785 USA. RP Aglitskiy, Y (reprint author), Sci Applicat Int Corp, Mclean, VA 22102 USA. NR 38 TC 68 Z9 74 U1 0 U2 8 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 AUG 1 PY 1998 VL 37 IS 22 BP 5253 EP 5261 DI 10.1364/AO.37.005253 PG 9 WC Optics SC Optics GA 106AJ UT WOS:000075107300031 PM 18286004 ER PT J AU Seaver, M Roselle, DC Pinto, JF Eversole, JD AF Seaver, M Roselle, DC Pinto, JF Eversole, JD TI Absolute emission spectra from Bacillus subtilis and Escherichia coli vegetative cells in solution SO APPLIED OPTICS LA English DT Article ID DECAY CHARACTERISTICS; STEADY-STATE; FLUORESCENCE; BACTERIA; IDENTIFICATION AB Spectrally resolved emission (270-560 Mn) from dilute suspensions of washed Bacillus subtilis and Escherichia coli were measured by use of tunable laser excitation between 270 and 300 nm. Integrated absolute emission cross sections increase with decreasing excitation wavelength and range from 1.8 x 10(-12) to 6.0 x 10(-11) cm(2)/(particle sr). An emission band near 340 nm dominates all observed spectra. At each excitation wavelength spectrally resolved emissions from the E. coli and B. subtilis suspensions are indistinguishable. C1 USN, Res Lab, Washington, DC 20375 USA. RP Seaver, M (reprint author), USN, Res Lab, Code 5610,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 23 TC 24 Z9 24 U1 0 U2 8 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 AUG 1 PY 1998 VL 37 IS 22 BP 5344 EP 5347 DI 10.1364/AO.37.005344 PG 4 WC Optics SC Optics GA 106AJ UT WOS:000075107300043 PM 18286016 ER PT J AU Rosen, DL Lambrakos, SG AF Rosen, DL Lambrakos, SG TI Modulated reflectance analysis of complex surface structures SO APPLIED SPECTROSCOPY LA English DT Article DE response; window; reflectivity; electroreflectivity; plasmon; nonlocal ID SILVER AB An analytical approach is presented for correlating modulated reflectance spectra and complex surface structure. A response function is constructed of specular reflectance from metal surfaces that are both rough and spatially dispersive. The method of analysis is based on a response function formulation that entails a windowing operation. This windowing operation is not ad hoc and is theoretically well founded for providing a statistical interpretation of the permittivity function. The initial analysis indicates that the windowing operation provides for a robust formulation that is conveniently adaptable to a wide range of frequencies, spanning regimes characterized by different response characteristics. A prototype case using this windowed response function formulation is applied to the electroreflectivity spectra, from 1.5 to 4.5 eV, of roughened silver electrodes. The electrode is modeled by a two-interface system as the basis of a parameterization of experimentally measured response functions, which are partitioned into reflectivity and transparent regimes by the windowing operation. The bulk plasmons and defect polaritons are characterized by our robust formulation. In addition, we present a discussion of the general significance of our approach with respect to the application of statistical pattern recognition to the analysis of modulated reflectivity data. C1 USA, Res Lab, Battlefield Environm Directorate, Adelphi, MD 20783 USA. USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. RP Rosen, DL (reprint author), USA, Res Lab, Battlefield Environm Directorate, Adelphi, MD 20783 USA. NR 17 TC 0 Z9 0 U1 0 U2 1 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD AUG PY 1998 VL 52 IS 8 BP 1053 EP 1061 DI 10.1366/0003702981944940 PG 9 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 115TQ UT WOS:000075681900005 ER PT J AU Canaan, T D'Alesandro, MM Miller, GA AF Canaan, T D'Alesandro, MM Miller, GA TI Cytokine production by cryopreserved human peripheral blood mononuclear cells in response to periodontal pathogens SO ARCHIVES OF ORAL BIOLOGY LA English DT Article DE cytokine; cryopreserved; lymphocyte; periodontal; mononuclear cell ID SURFACE-MARKERS; SUPERANTIGEN AB Freezing techniques provide a way of repeating and extending immunological assays by using frozen portions of an individual's peripheral blood mononuclear cell fraction. Earlier work shows that the lymphocytes that are stored frozen retain their ability to respond to polyclonal B-cell activators, mitogens, superantigens and bacterial extracts of oral interest. These studies extend previous findings by determining cytokine production by lymphocytes following frozen storage for up to 24 weeks. Production of interleukin (IL)-1 beta, IL-2, IL-6, and tumour necrosis factor (TNF)-beta by stimulated lymphocytes after cyropreservation was not significantly different from those responses before storage, with one exception: IL-6 production was negligible after 24 weeks' frozen storage when thawed cells were cocultured with pokeweed mitogen. After stimulation with extracts from Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans, the proliferative capacity of the frozen cells was maintained as well as the production of IL-1 beta, IL-2, and IL-6. TNF-beta was not produced in response to bacterial antigen stimulation. The ability of peripheral blood mononuclear cells to retain functional activity after frozen storage should permit more effective monitoring during longitudinal clinical studies and a better evaluation of changes in cytokine production in patients with advanced periodontitis both during and after treatment. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Geocenters Inc, Ft Washington, MD 20744 USA. USN, Sch Dent, Natl Naval Dent Ctr, Bethesda, MD 20814 USA. USN, Dent Res Inst Detachment, Bethesda, MD 20889 USA. RP Miller, GA (reprint author), Geocenters Inc, Ft Washington, MD 20744 USA. NR 23 TC 2 Z9 2 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0003-9969 J9 ARCH ORAL BIOL JI Arch. Oral Biol. PD AUG PY 1998 VL 43 IS 8 BP 657 EP 664 DI 10.1016/S0003-9969(98)00053-3 PG 8 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 115UF UT WOS:000075683300009 PM 9758049 ER PT J AU Stuart, SM Nowicki, MJ AF Stuart, SM Nowicki, MJ TI Radiological case of the month - Cat-scratch disease with hepatic and splenic involvement SO ARCHIVES OF PEDIATRICS & ADOLESCENT MEDICINE LA English DT Article ID GRANULOMATOUS HEPATITIS; ROCHALIMAEA-HENSELAE; IMAGING FEATURES; UNKNOWN ORIGIN; FEVER; ADENOPATHY; CHILDREN; LESIONS C1 Natl Naval Med Ctr, Div Gastroenterol, Dept Pediat, Portsmouth, VA 23708 USA. Natl Naval Med Ctr, Div Pediat Gastroenterol, Dept Pediat, Portsmouth, VA 23708 USA. RP Nowicki, MJ (reprint author), Natl Naval Med Ctr, Div Gastroenterol, Dept Pediat, 620 John Paul Jones Cir, Portsmouth, VA 23708 USA. NR 17 TC 3 Z9 3 U1 0 U2 0 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 1072-4710 J9 ARCH PEDIAT ADOL MED JI Arch. Pediatr. Adolesc. Med. PD AUG PY 1998 VL 152 IS 8 BP 823 EP 824 PG 2 WC Pediatrics SC Pediatrics GA 106JQ UT WOS:000075126500025 PM 9701150 ER PT J AU Worley, CE Mason, BD AF Worley, CE Mason, BD TI Micrometer measures of double stars SO ASTRONOMICAL JOURNAL LA English DT Review DE binaries : close; binaries : visual ID VISUAL DOUBLE STARS; ORBITAL ELEMENTS; SPECKLE INTERFEROMETRY; BINARY STARS; SYSTEMS; PAIRS; WDS AB Micrometer measures of 795 double stars made with the 26 inch (0.66 m) refractor of the US Naval Observatory from 1984 to 1990 are presented. C1 USN Observ, Washington, DC 20392 USA. RP Worley, CE (reprint author), USN Observ, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. NR 136 TC 0 Z9 0 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 AUG PY 1998 VL 116 IS 2 BP 917 EP 930 DI 10.1086/300475 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 115CW UT WOS:000075646800031 ER PT J AU Dyck, HM van Belle, GT Thompson, RR AF Dyck, HM van Belle, GT Thompson, RR TI Radii and effective temperatures for K and M giants and supergiants. II. SO ASTRONOMICAL JOURNAL LA English DT Article DE stars : fundamental parameters; stars : late-type ID ANGULAR DIAMETERS; MICHELSON INTERFEROMETRY; CATALOG; COOLER; STARS AB We present new interferometric observations for 74 luminous red stars, made in the near-infrared. We show that our 2.2 mu m uniform-disk diameters agree with other near-infrared diameter determinations (lunar occultations and interferometers) for 22 stars measured in common with ours. From our new data, we derive effective temperatures that are compared with our previous work and with comparable observations made by lunar occultations at Kitt Peak. The combined data set yields 91 luminosity class II, II-III, and III stars that have well-determined spectral types spanning the range from about K0 to about M8. There are 83 stars in the sample that define an approximately linear relationship between spectral type and effective temperature for giants, with a dispersion of 192 K at each spectral type. Eight of the stars have temperatures that are roughly 750 K too low for their spectral types. These stars are not known to be at the high-luminosity end of the range of stars observed and are not recognized as binary stars. At present, we have no explanation for their low effective temperatures. We also show that Hipparcos parallaxes, combined with our angular diameters, yield linear radii precise enough to see differences in the average radius between luminosity class II and luminosity class III stars. C1 USN Observ, Dept Astrometry, Navy Prototype Opt Interferometer, Flagstaff, AZ 86001 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. RP Dyck, HM (reprint author), USN Observ, Dept Astrometry, Navy Prototype Opt Interferometer, Rural Route 14,Box 447, Flagstaff, AZ 86001 USA. EM meldyck@sextans.lowell.edu; gerard@huey.jpl.nasa.gov; thompson@sparky.uwyo.edu NR 21 TC 93 Z9 93 U1 0 U2 3 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 AUG PY 1998 VL 116 IS 2 BP 981 EP 986 DI 10.1086/300453 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 115CW UT WOS:000075646800036 ER PT J AU Canzian, B AF Canzian, B TI Extensive spiral structure and corotation resonance SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : kinematics and dynamics; galaxies : spiral; galaxies : structure ID PISCES-PERSEUS SUPERCLUSTER; H-I OBSERVATIONS; LARGE-SCALE STRUCTURE; 21 CM SURVEY; NEUTRAL HYDROGEN; STAR-FORMATION; CANCER CLUSTER; DISK GALAXIES; 21-CM SURVEY; GAS AB Spiral density wave theories demand that grand-design spiral structure be bounded, at most, between the inner and outer Lindblad resonances of the spiral pattern. The corotation resonance lies between the outer and the inner Lindblad resonances. The locations of the resonances are at radii whose ratios to each other are rather independent of the shape of the rotation curve. The measured ratio of outer to inner extent of spiral structure for a given spiral galaxy can be compared to the standard ratio of corotation to inner Lindblad resonance radius. In the case that the measured ratio far exceeds the standard ratio, it is likely that the corotation resonance is within the bright optical disk. Studying such galaxies can teach us how the action of resonances sculpts the appearance of spiral disks. This paper reports observations of 140 disk galaxies, leading to resonance ratio tests for 109 qualified spiral galaxies. It lists candidates that have a good chance of having the corotation resonance radius within the bright optical disk. C1 USN Observ, Univ Space Res Assoc, Flagstaff, AZ 86002 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Canzian, B (reprint author), USN Observ, Univ Space Res Assoc, POB 1149, Flagstaff, AZ 86002 USA. NR 64 TC 12 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 AUG 1 PY 1998 VL 502 IS 2 BP 582 EP 597 DI 10.1086/305912 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KF UT WOS:000077776000007 ER PT J AU Feldman, U Brown, CM Laming, JM Seely, JF Doschek, GA AF Feldman, U Brown, CM Laming, JM Seely, JF Doschek, GA TI A compact spectral range and matching extreme-ultraviolet spectrometer for the simultaneous study of 1 x 10(4)-2 x 10(7) K solar plasmas SO ASTROPHYSICAL JOURNAL LA English DT Article DE instrumentation : spectrographs; Sun : chromosphere; Sun : flares; Sun : UV radiation ID ELECTRON-IMPACT EXCITATION; FINE-STRUCTURE TRANSITION; BORON-LIKE IONS; O-IV; RATE COEFFICIENTS; ATOMIC DATA; ATMOSPHERE; SUMER; LINE; EMISSION AB An EUV spectral range of less than 100 Angstrom in first order has been found that includes sufficient spectral lines and critical combinations of lines in first and second order to permit dynamic and diagnostic investigations of the solar atmosphere with a relatively simple spectrometer. An optical design of such a spectrometer, based on the performance of the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer on the Solar and Heliospheric Observatory (SOHO) spacecraft, and sample stigmatic solar spectra for the range 1334-1428 Angstrom from SUMER are presented to illustrate the utility of this range. Lines of almost all abundant solar elements except H and He are present within this wavelength band in first or second order. The lines cover the large temperature range from 1 x 10(4) K (chromosphere) to 2 x 10(7) K (flares). The spectrometer's resolution is sufficiently high to permit measuring line profiles and wavelength shifts which allows plasma dynamical studies of individual solar structures from the chromosphere up into the corona. In addition, electron density diagnostics are available within the spectral range that cover the temperature range from 8 x 10(4) to 1 x 10(6) K and an electron density range from 10(8) to 10(13) cm(-3). C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Sachs Freeman Associates Inc, Largo, MD 20774 USA. RP Feldman, U (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 28 TC 3 Z9 3 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 AUG 1 PY 1998 VL 502 IS 2 BP 997 EP 1005 DI 10.1086/305931 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KF UT WOS:000077776000039 ER PT J AU Antiochos, SK AF Antiochos, SK TI The magnetic topology of solar eruptions SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; Sun : flares; Sun : magnetic fields; Sun : prominences ID FIELD; CONFIGURATIONS; ENERGY; LINES; SHEAR AB We present an explanation for the well-known observation that complexity of the solar magnetic field is a necessary ingredient for strong activity such as large eruptive flares. Our model starts with the standard picture for the energy buildup-a highly sheared, newly emerged magnetic field near the photospheric neutral line held down by an overlying unsheared held. Previously, we proposed the key new idea that magnetic reconnection between the unsheared field and neighboring flux systems decreases the amount of the overlying field and, thereby, allows the low-lying sheared flux to "break out." In this Letter, we show that a bipolar active region does not have the necessary complexity for this process to occur, but a delta sunspot has the right topology for magnetic breakout. We discuss the implications of these results for observations from SOHO and TRACE. C1 USN, EO Hulburt Ctr Space Res, Res Lab, Washington, DC 20375 USA. RP Antiochos, SK (reprint author), USN, EO Hulburt Ctr Space Res, Res Lab, Washington, DC 20375 USA. RI Antiochos, Spiro/D-4668-2012 OI Antiochos, Spiro/0000-0003-0176-4312 NR 13 TC 161 Z9 164 U1 1 U2 5 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 AUG 1 PY 1998 VL 502 IS 2 BP L181 EP L184 DI 10.1086/311507 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152KH UT WOS:000077776200019 ER PT J AU Fajardo, AB Luke, BL Grant, JW AF Fajardo, AB Luke, BL Grant, JW TI A technique for determining convergence in human subjects undergoing rotational acceleration using a binocular eye-tracking system SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article; Proceedings Paper CT Aerospace-Medical-Association 67th Annual Meeting CY MAY 08, 1996 CL ATLANTA, GEORGIA SP Aerosp Med Assoc AB Background: This report describes the measurement of convergent eye movements and calculation of the spatial convergence point from the angular eye position data. These measurements were made in the dark while the subject experienced inertial motion aboard a centrifuge. This was an exploratory experiment with the goal of evaluating the eyes' convergence in the dark, and to see if this convergence point is dependent on inertial motion. Methods: The subject was rotated in the dark on NAMRL's Coriolis Acceleration Platform in Pensacola, FL. The pupil positions were tracked by two helmet-mounted infrared cameras connected to a computer-controlled data acquisition system. We used the position data to calculate the angles through which the eyes rotated, and then applied trigonometric principles to construct the line of sight for each eye for any instant: in time. The intersection of these two lines of sight was the convergence point. Results: With the binocular eye-tracking system, we could accurately determine an accelerating subject's convergence point to within 10%, if the point was less than 1.5 m away from the subject. At convergence distances greater than 1.5 m, the angular movements of the two eyes became so small that determining a convergence point was difficult. C1 Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. USN, Aerosp Med Res Lab, Pensacola, FL USA. RP Grant, JW (reprint author), Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. NR 9 TC 2 Z9 2 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 AUG PY 1998 VL 69 IS 8 BP 750 EP 754 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 106WT UT WOS:000075174600004 PM 9715962 ER PT J AU Feeks, EF Maino, TJ Proctor, JG Bower, EA AF Feeks, EF Maino, TJ Proctor, JG Bower, EA TI An abscess that wasn't: Renal calyceal diverticulum in a student naval aviator SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID SHOCK-WAVE LITHOTRIPSY; PYELOCALICEAL DIVERTICULA; CALICEAL DIVERTICULA; MANAGEMENT; RUPTURE AB The authors report a case of a 24-yr-old female Navy student pilot who presented with pyelonephritis, and on workup, was found to have two diverticula arising from calyces in her left kidney. Her infection resolved after several weeks of antibiotic therapy. She was granted a waiver to return to flight status based on the judgment that her risk of recurrent infection, sudden incapacitation, future need of surgery, and compromise of mission effectiveness were acceptably low. She has remained asymptomatic after more than 48 mo of follow-up. Renal calyceal diverticulum has not previously been discussed in the literature of aerospace medicine. The definition, anatomy, possible etiologies, epidemiology, presentation, treatment options, and aeromedical disposition, including human-machine interface issues, for calyceal diverticula are discussed. Aviators with calyceal diverticula are at increased risk of urinary tract infection and other complications; aeromedical disposition should rest on evaluation of such risk on a case-by-case basis. C1 USN, Training Air Wing FIVE, Whiting Field, FL USA. Univ Colorado, Sch Med, Boulder, CO 80309 USA. USN Hosp, Dept Urol, Pensacola, FL USA. USN, Aerosp & Operat Med Inst, Pensacola, FL USA. RP Feeks, EF (reprint author), USN, Quarters 36,Barrancas Area, NAS Pensacola, FL 32508 USA. NR 28 TC 1 Z9 1 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 AUG PY 1998 VL 69 IS 8 BP 785 EP 787 PG 3 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 106WT UT WOS:000075174600011 PM 9715969 ER PT J AU Mandell, AJ Owens, MJ Selz, KA Morgan, WN Shlesinger, MF Nemeroff, CB AF Mandell, AJ Owens, MJ Selz, KA Morgan, WN Shlesinger, MF Nemeroff, CB TI Mode matches in hydrophobic free energy eigenfunctions predict peptide-protein interactions SO BIOPOLYMERS LA English DT Article DE hydrophobic free energy eigenfunction; peptide hydrophobic wavelets; peptide power spectra; hydrophobic modes; dopamine D(2) receptor; dopamine transporter (DAT); neurotensin; cholecystokinin ID MEMBRANE-PROTEINS; HORMONE RECEPTOR; AMINO-ACIDS; TRANSPORTERS; DOPAMINE; CHOLECYSTOKININ; RAT; IMMUNOREACTIVITY; NEUROTENSIN; SPECIFICITY AB The dominant statistical hydrophobic free energy inverse frequencies, amino acid wavelengths as hydrophobic modes, of neurotensin (NT), cholescystokinin (CCK), the human dopamine D(2) receptor [(DA)D(2)], and the human dopamine transporter (DAT) were determined using orthogonal decomposition of the autocovariance matrices of their amino acid sequences as hydrophobic free energy equivalents in kcal/mol. The leading eigenvalues-associated eigenvectors were convolved with the original series to construct eigenfunctions. Eigenfunctions were further analyzed using discrete trigonometric wavelet and all pales, maximum entropy power spectral transformations. This yielded clean representations of the dominant hydrophobic free energy modes, most of which are otherwise lost in the smoothing of hydropathy plots or contaminated by end effects and multimodality in conventional Fourier transformations, Mode matches were found between NT and (DA)D(2) and between CCK and DAT, but not the converse. These mode matches successfully predicted the nonlinear kinetic interactions of NT-(DA)D(2) in contrast with CCK-(DA)D(2) on (3)H-spiperone binding to (DA)D(2), and by CCK-DAT but not NT-DAT on [N-methyl-(3)H]-WIN 35,428 binding to DAT in (DA)D(2) and DAT cDNA stably transfected cell lines without known NT or CCK receptors. Computation of the dominant modes of hydrophobic free energy eigenfunctions may help predict functionally relevant peptide-membrane protein interactions, even across neurotransmitter families. (C) 1998 John Wiley & Sons, Inc. C1 Emory Univ, Sch Med, Cielo Inst, Atlanta, GA 30322 USA. Emory Univ, Sch Med, Dept Psychiat, Atlanta, GA 30322 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, 486 Sunset Dr, Asheville, NC 28804 USA. RI Owens, Michael/G-5191-2012 FU NIMH NIH HHS [R43 MH58026-01] NR 64 TC 30 Z9 31 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0006-3525 J9 BIOPOLYMERS JI Biopolymers PD AUG PY 1998 VL 46 IS 2 BP 89 EP 101 PG 13 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA ZV643 UT WOS:000074326400004 PM 9664843 ER PT J AU Kleiman, VD Arrivo, SM Melinger, JS Heilweil, EJ AF Kleiman, VD Arrivo, SM Melinger, JS Heilweil, EJ TI Controlling condensed-phase vibrational excitation with tailored infrared pulses SO CHEMICAL PHYSICS LA English DT Article ID LASER-PULSES; SELECTIVE EXCITATION; FEMTOSECOND PULSES; SCATTERING; DYNAMICS; LADDER AB Vibrational population distributions within the CO-stretching T-1u manifold of W(CO)(6) in room-temperature n-hexane were created by using near-transform limited and linearly chirped picosecond infrared excitation pulses. These pulses were characterized using the second harmonic FROG (frequency-resolved optical gating) algorithm to determine the similar to 8 cm(-1)/ps chirp for both positively- and negatively-chirped 2 ps pulses. FROG and time-resolved transient difference spectra were obtained with an InSb focal plane array detector. While unchirped and positively-chirped excitation leads predominantly to upsilon = 1 population, negatively-chirped pulses produce excess population in the Li = 2 level. These results are compared to predictions from density matrix calculations for a model potential. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. USN, Res Lab, Div Condensed Matter & Radiat Sci, Washington, DC 20375 USA. RP Heilweil, EJ (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RI Kleiman, Valeria/H-7818-2013 OI Kleiman, Valeria/0000-0002-9975-6558 NR 24 TC 49 Z9 49 U1 0 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD AUG 1 PY 1998 VL 233 IS 2-3 BP 207 EP 216 DI 10.1016/S0301-0104(97)00367-4 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 108HU UT WOS:000075260900006 ER PT J AU Holland, KT AF Holland, KT TI Beach cusp formation and spacings at Duck, USA SO CONTINENTAL SHELF RESEARCH LA English DT Article DE beach cusps; swash; video imaging ID NATURAL BEACH; FIELD; SWASH AB Approximately nine years of daily video images from Duck, NC, USA, were analyzed to determine the timing of cusp formation in relation to environmental forcing and the distances separating consecutive cusp horns. 57 independent cusp events (defined as transitions from visibly smooth to cuspate topography) were observed with most of the cusps forming after storms. The temporal lag between the peak in storm intensity and cusp development was typically 3 days. Approximately half of the cusp events had formations predicted by an empirical threshold relating storm presence, breaker angle, and beach reflectivity. This threshold and other statistical observations suggest that Duck cusps form as energy conditions become more reflective, as the offshore wave angle approaches normal incidence and as the directional spread of the incident wave field becomes narrower. The standard deviation of the observed spacings relative to the mean spacing for each event was around 15% with the range in spacings for each event being typically less than half the event's mean cusp width. There were no strong statistical relationships between mean cusp spacings and environmental parameters (such as swash excursion lengths). Copyright (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Holland, KT (reprint author), USN, Res Lab, Code 7442, Stennis Space Ctr, MS 39529 USA. RI Holland, K. Todd/A-7673-2011 OI Holland, K. Todd/0000-0002-4601-6097 NR 30 TC 22 Z9 24 U1 0 U2 2 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 AUG PY 1998 VL 18 IS 10 BP 1081 EP 1098 DI 10.1016/S0278-4343(98)00024-7 PG 18 WC Oceanography SC Oceanography GA 131NZ UT WOS:000076583300002 ER PT J AU Schoelch, SB Barrett, TL AF Schoelch, SB Barrett, TL TI Umbilical pilonidal sinus SO CUTIS LA English DT Article AB Although most cases of pilonidal sinus occur in the sacrococcygeal region, umbilical presentations can occur. Due to the risk of peritoneal extension of inflammation from this lesion, the umbilical pilonidal sinus should be treated more aggressively than its sacrococcygeal counterpart. Pilonidal sinus should therefore be included in the differential diagnosis of umbilical nodules. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Dermatol, San Diego, CA 92134 USA. RP Schoelch, SB (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 7 TC 7 Z9 7 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD AUG PY 1998 VL 62 IS 2 BP 83 EP 84 PG 2 WC Dermatology SC Dermatology GA 109MQ UT WOS:000075326700009 PM 9714903 ER PT J AU McKinlay, JR Kaiser, J Barrett, TL Graham, B AF McKinlay, JR Kaiser, J Barrett, TL Graham, B TI Blue rubber bleb nevus syndrome SO CUTIS LA English DT Article AB Blue rubber bleb nevus syndrome is a rare autosomal dominant disorder of multiple venous malformations of the skin and gastrointestinal tract. The fragility of the gastrointestinal lesions may lead to significant occult blood loss and subsequent anemia. C1 USN, San Diego Med Ctr, Dept Clin Res, San Diego, CA 92134 USA. USN, San Diego Med Ctr, Dept Dermatol, San Diego, CA 92134 USA. RP McKinlay, JR (reprint author), USN, San Diego Med Ctr, Dept Clin Res, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 9 TC 6 Z9 6 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD AUG PY 1998 VL 62 IS 2 BP 97 EP 98 PG 2 WC Dermatology SC Dermatology GA 109MQ UT WOS:000075326700013 PM 9714907 ER PT J AU Ash, K Lord, J Zukowski, M McDaniel, DH AF Ash, K Lord, J Zukowski, M McDaniel, DH TI Comparison of topical therapy for striae alba (20% glycolic acid 0.05% tretinoin versus 20% glycolic acid 10% L-ascorbic acid) SO DERMATOLOGIC SURGERY LA English DT Article ID ALPHA-HYDROXY ACIDS; PHOTOAGED SKIN; DOUBLE-BLIND; STRETCH MARKS; DISTENSAE; CREAMS AB BACKGROUND. Topical treatment of striae rubra with 0.1% tretinoin and laser treatment of striae rubra and alba with the 585-nm pulsed dye laser are proven therapeutic options. However, little efficacy has been shown for treatment of striae alba topically, and the laser is currently not a suitable treatment option for darker ethnic skin types. OBJECTIVE. The purpose of this study was to demonstrate that selected commercial topical agents can improve the appearance of striae alba. METHODS. Ten patients of varying skin types (I-V) having striae distensae alba on the abdomen or thighs were selected to evaluate the effectiveness of two topical treatment regimens. Patients were placed on daily topical application of 20% glycolic acid (MD Forte) to the entire treatment area. In addition, the patients applied 10% L-ascorbic acid, 2% zinc sulfate, and 0.5% tyrosine to half to the treatment area and 0.05% tretinoin emollient cream (Renova) to the other half of the treatment area. The creams were applied on a daily basis for 12 weeks. Improvement teas evaluated at 4 and 12 weeks in an objective unblinded fashion at the follow-up visits, a objective blinded fashion by visual grading at the conclusion of the study, and in an objective blinded fashion with profilometry. Additionally, histopathologic analysis was performed. RESULTS. Analysis of these data reveals: 1) both regimens can improve the appearance of stretch marks; 2) these topical therapy regimens are safe and effective in study patients with minimal irritation; 3) elastin content within the reticular and papillary dermis can increase with topical 20% glycolic acid combined with 0.05% tretinoin emollient cream therapy; 4) both regimens increased epidermal thickness and decreased papillary dermal thickness in treated stretch marks when compared with untreated stretch marks; 5) combined epidermal and papillary dermal thickness in stretch marks treated with either topical regimen approaches that of normal skin; and 6) profilometry can objectively measure differences in skin texture associated with striae treatments when compared to controls, however, it is not sensitive enough to justify comparison or quantitative improvements between similarly effective treatments. (C) 1998 by the American Society for Dermatologic Surgery, Inc. Dermatol Surg 1998;24:849-856. C1 USN, Med Ctr, Dept Gen Surg, Portsmouth, VA USA. USN, Med Ctr, Dept Plast & Reconstruct Surg, Portsmouth, VA USA. Eastern Virginia Med Sch, Laser Ctr Virginia, Virginia Beach, VA USA. RP McDaniel, DH (reprint author), 933 1st Colonial Rd,Suite 113, Virginia Beach, VA 23454 USA. NR 26 TC 38 Z9 38 U1 1 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1076-0512 J9 DERMATOL SURG JI Dermatol. Surg. PD AUG PY 1998 VL 24 IS 8 BP 849 EP 856 PG 8 WC Dermatology; Surgery SC Dermatology; Surgery GA 112BR UT WOS:000075474700006 PM 9723049 ER PT J AU Wu, F Chen, LG Sun, FR Wu, C Hua, PQ AF Wu, F Chen, LG Sun, FR Wu, C Hua, PQ TI Optimum performance parameters for a quantum carnot heat pump with spin-1/2 SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE spin-1/2 system; quantum heat pump; finite-time thermodynamics; modern statistical mechanics ID FINITE-TIME; ENGINE; THERMODYNAMICS; CYCLES; MODEL AB The purpose of this paper is to study the optimal performance for an endoreversible Carnot heat pump with a working fluid system consisting of many spin-1/2 fermi. The relationship between the optimal heating load and the coefficient of performance (COP) for the quantum Carnot heat pump is derived. The optimum parameters are obtained at a maximum heating load point and at a maximum ecological function point, respectively. Published by Elsevier Science Ltd. C1 Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. USN Acad, Dept Engn Mech, Annapolis, MD 21402 USA. Wuhan Inst Chem Technol, Fac Phys, Wuhan 430073, Peoples R China. RP Wu, F (reprint author), Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. EM wu@arctic.nadn.navy.mil NR 24 TC 31 Z9 37 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0196-8904 J9 ENERG CONVERS MANAGE JI Energy Conv. Manag. PD AUG PY 1998 VL 39 IS 11 BP 1161 EP 1167 DI 10.1016/S0196-8904(98)00004-1 PG 7 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA ZT638 UT WOS:000074107900005 ER PT J AU Brandt, JE Medin, JA Rosler, ES Li, C Chute, JP Hoffman, R AF Brandt, JE Medin, JA Rosler, ES Li, C Chute, JP Hoffman, R TI High-level transgene expression by human CD34(+)CD38(+) hematopoietic stem cells following in vitro expansion. SO EXPERIMENTAL HEMATOLOGY LA English DT Meeting Abstract C1 Univ Illinois, Chicago, IL USA. USN, Med Res Inst, Bethesda, MD USA. NR 0 TC 0 Z9 0 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 AUG PY 1998 VL 26 IS 8 MA 24 BP 687 EP 687 PG 1 WC Hematology; Medicine, Research & Experimental SC Hematology; Research & Experimental Medicine GA 118GT UT WOS:000075830600026 ER PT J AU Brandt, JE Bartholomew, AM Nelson, MC Chute, JP Turian, JV Chen, L Hoffman, R AF Brandt, JE Bartholomew, AM Nelson, MC Chute, JP Turian, JV Chen, L Hoffman, R TI Rescue of lethally myeloablated baboons with ex vivo expanded grafts results in delayed engraftment. SO EXPERIMENTAL HEMATOLOGY LA English DT Meeting Abstract C1 Univ Illinois, Chicago, IL USA. USN, Med Res Inst, Bethesda, MD USA. NR 0 TC 3 Z9 3 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 AUG PY 1998 VL 26 IS 8 MA 58 BP 699 EP 699 PG 1 WC Hematology; Medicine, Research & Experimental SC Hematology; Research & Experimental Medicine GA 118GT UT WOS:000075830600060 ER PT J AU Chute, JP Saini, AA Wells, MR Clark, W Smoot, D Harlan, DM St Louis, D Kaushal, S Davis, TA AF Chute, JP Saini, AA Wells, MR Clark, W Smoot, D Harlan, DM St Louis, D Kaushal, S Davis, TA TI Coculture of human CD34(+)CD38(+) cells with procine microvascular endothelial cells (PMVEC) or PMVEC-Conditioned media enhances retroviral mediated gene transfer. SO EXPERIMENTAL HEMATOLOGY LA English DT Meeting Abstract C1 USN, Med Res Inst, Uniformed Serv Univ Hlth Sci, Bethesda, MD USA. NR 0 TC 0 Z9 0 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 AUG PY 1998 VL 26 IS 8 MA 279 BP 761 EP 761 PG 1 WC Hematology; Medicine, Research & Experimental SC Hematology; Research & Experimental Medicine GA 118GT UT WOS:000075830600281 ER PT J AU Kaushal, S St Louis, D Saini, AA Wells, M Clark, W Smoot, D Harlan, DM Davis, TA Chute, JP AF Kaushal, S St Louis, D Saini, AA Wells, M Clark, W Smoot, D Harlan, DM Davis, TA Chute, JP TI Expression of GLVR-1 and GLVR-2 on human CD34+CD38- bone marrow cells following co-culture with porcine microvascular endothelial cells (PMVEC) and liquid culture with PMVEC-CM. SO EXPERIMENTAL HEMATOLOGY LA English DT Meeting Abstract C1 USN, Med Res Inst, Uniformed Serv Univ Hlth Sci, Bethesda, MD USA. NR 0 TC 0 Z9 0 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 AUG PY 1998 VL 26 IS 8 MA 280 BP 761 EP 761 PG 1 WC Hematology; Medicine, Research & Experimental SC Hematology; Research & Experimental Medicine GA 118GT UT WOS:000075830600282 ER PT J AU Lum, LG Lefever, AV Treisman, J Garlie, N Kistler, AM Yuille, DL Levine, BL June, CH Hanson, JP AF Lum, LG Lefever, AV Treisman, J Garlie, N Kistler, AM Yuille, DL Levine, BL June, CH Hanson, JP TI Phase I study of anti-CD3/anti-CD28 coactivated T cells (COACTS) in cancer patients: Enhanced Th-1 responses in vivo SO EXPERIMENTAL HEMATOLOGY LA English DT Meeting Abstract C1 St Lukes Med Ctr, Milwaukee, WI USA. USN, Med Res Inst, Bethesda, MD USA. RI Levine, Bruce/D-1688-2009 NR 0 TC 1 Z9 1 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 AUG PY 1998 VL 26 IS 8 MA 324 BP 772 EP 772 PG 1 WC Hematology; Medicine, Research & Experimental SC Hematology; Research & Experimental Medicine GA 118GT UT WOS:000075830600326 ER PT J AU Coss, HS Manos, RE Buoncristiani, A Mills, WJ AF Coss, HS Manos, RE Buoncristiani, A Mills, WJ TI Abduction stress and AP weightbearing radiography of purely ligamentous injury in the tarsometatarsal joint SO FOOT & ANKLE INTERNATIONAL LA English DT Article ID FRACTURE-DISLOCATION; DIAGNOSIS AB Twenty volunteers (40 feet) with no prior foot injury underwent standardized abduction stress and standing AP radiographs. Subsequently, the Lisfranc and dorsal tarsometatarsal ligaments in nine feet from cadavers were sectioned in a varying sequential manner, and interval standardized radiographs of abduction stress and AP simulated weightbearing were obtained. On abduction stress radiographs in 39 of 40 feet of volunteers and nine of nine feet of cadavers before sectioning, a line tangential to the medial aspect of the navicular and medial cuneiform (medial column line) intersected the base of the first metatarsal. Combining the sectioning of the Lisfranc and dorsal tarsometatarsal ligaments produced a disruption of the medial column line in all feet from cadavers. Disruption of this medial column line may be a simple and valuable diagnostic tool for determining significant ligamentous injury to the tarsometatarsal interval. C1 USN Hosp, Dept Orthoped Surg & Clin Invest, San Diego, CA 92134 USA. RP Mills, WJ (reprint author), US Navy Reserve, Naval Med Ctr, Dept Orthoped Surg, San Diego, CA 92134 USA. NR 32 TC 40 Z9 43 U1 0 U2 5 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 1071-1007 J9 FOOT ANKLE INT JI Foot Ankle Int. PD AUG PY 1998 VL 19 IS 8 BP 537 EP 541 PG 5 WC Orthopedics SC Orthopedics GA 112FN UT WOS:000075483600006 PM 9728701 ER PT J AU Hacker, P Firing, E Hummon, J Gordon, AL Kindle, JC AF Hacker, P Firing, E Hummon, J Gordon, AL Kindle, JC TI Bay of Bengal currents during the northeast monsoon SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID INDIAN-OCEAN AB Velocity and property observations were made during February and March 1995 as part of the World Ocean Circulation Experiment (WOCE) Hydrographic Program (WHP) expedition in the Indian Ocean. The observed circulation in the upper 300 m of the ocean during the northeast monsoon is compared to the output of a high-resolution, S-layer, nonlinear model forced by European Center for Medium Range Weather Forecasting (ECMWF) winds. The data identify several new features in the Bay of Bengal: a shelf-break coastal current in the northeast corner, an eddy and subsurface jet near the South Preparis Channel, and an eastward countercurrent extending from 80 degrees E to the eastern boundary. The countercurrent transports high-salinity surface water from the northwest Indian Ocean into the bay, and separates the historically observed North Equatorial Current into two currents with separate sources and water properties. The data also detail the spatial structure of the South Equatorial Current and Countercurrent, and show the Equatorial Undercurrent in the eastern half of the Indian Ocean. The model compares well enough with the data to suggest that such realistic models may provide a useful temporal context for the WHP snapshot. C1 USN, Res Ctr, Stennis Space Ctr, MS 39529 USA. Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY USA. Univ Hawaii, Honolulu, HI 96822 USA. RP Hacker, P (reprint author), JIMAR, 1000 Pope Rd, Honolulu, HI 96822 USA. EM hacker@soest.hawaii.edu; agordon@ldgo.columbia.edu; kindle@polaris.nrlssc.navy.mil RI Gordon, Arnold/H-1049-2011 OI Gordon, Arnold/0000-0001-6480-6095 NR 13 TC 27 Z9 28 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG 1 PY 1998 VL 25 IS 15 BP 2769 EP 2772 DI 10.1029/98GL52115 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 108WZ UT WOS:000075289900003 ER PT J AU Russell, CT Fedder, JA Slinker, SP Zhou, XW Le, G Luhmann, JG Fenrich, FR Chandler, MO Moore, TE Fuselier, SA AF Russell, CT Fedder, JA Slinker, SP Zhou, XW Le, G Luhmann, JG Fenrich, FR Chandler, MO Moore, TE Fuselier, SA TI Entry of the POLAR spacecraft into the polar cusp under northward IMF conditions SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID INTERPLANETARY MAGNETIC-FIELD; LATITUDE BOUNDARY-LAYER; RECONNECTION; INSTRUMENT; ANGLE AB On May 29, 1996 from 0200 to 0800 UT the solar wind dynamic pressure was high ranging from 6 to 8 nPa and the interplanetary field was almost due northward, ranging from 10 to 15 nT in BZ GSM. Even at apogee the POLAR spacecraft should not have entered the magnetosheath according to recent scaling laws. However, the magnetic field was greatly depressed below the value expected indicating the presence of significant plasma energy density throughout the high latitude magnetosphere surrounding the cusp. The presence of this plasma is confirmed by the plasma instrumentation on board the spacecraft. While the entry into this nearly stagnant plasma was gradual, the exit on to polar cap field lines was abrupt. We interpret these observations in terms of the post-cusp reconnection of the strongly northward interplanetary magnetic field. C1 Univ Calif Los Angeles, Inst Geophys, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. George Mason Univ, Inst Computat Sci & Informat, Fairfax, VA 22030 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Lockheed Martin, Palo Alto, CA USA. RP Russell, CT (reprint author), Univ Calif Los Angeles, Inst Geophys, Los Angeles, CA 90095 USA. RI Le, Guan/C-9524-2012; Moore, Thomas/D-4675-2012; OI Le, Guan/0000-0002-9504-5214; Moore, Thomas/0000-0002-3150-1137; Russell, Christopher/0000-0003-1639-8298 NR 18 TC 31 Z9 31 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 AUG 1 PY 1998 VL 25 IS 15 BP 3015 EP 3018 DI 10.1029/98GL00355 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 108WZ UT WOS:000075289900065 ER PT J AU Brueckner, GE Delaboudiniere, JP Howard, RA Paswaters, SE St Cyr, OC Schwenn, R Lamy, P Simnett, GM Thompson, B Wang, D AF Brueckner, GE Delaboudiniere, JP Howard, RA Paswaters, SE St Cyr, OC Schwenn, R Lamy, P Simnett, GM Thompson, B Wang, D TI Geomagnetic storms caused by coronal mass ejections (CMEs): March 1996 through June 1997 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ULTRAVIOLET AB (1) All but two geomagnetic storms with Kp greater than or equal to 6 during the operating period (March 1996 through June 1997) of the Large Angle Spectroscopic Coronagraph (LASCO) experiment on the Solar and Heliospheric Observatory (SOHO) spacecraft can be traced to Coronal Mass Ejections (CMEs). (2) These geomagnetic storms are not related to high speed solar wind streams. (3) The CMEs which cause geomagnetic effects, can be classified into two categories: Halo events and toroidal CMEs.. (4) The CMEs are accompanied by Coronal Shock Waves as seen in the Extreme Ultraviolet Imaging Telescope (EIT) Fe XII images. (5) Some CMEs are related to flares, others are not. (6) In many cases, the travel time between the explosion on the Sun and the maximum geomagnetic activity is about 80 hours. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. Astron Spatiale Lab, F-13376 Marseille, France. Max Planck Inst Aeron, D-37189 Katlenburg Lindau, Germany. Univ Birmingham, Space Res Grp, Birmingham B15 2TT, W Midlands, England. Space Applicat Corp, Vienna, VA 22180 USA. Interferometr Inc, Chantilly, VA USA. Computat Phys Inc, Fairfax, VA USA. RP Brueckner, GE (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RI Thompson, Barbara/C-9429-2012 NR 9 TC 111 Z9 112 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG 1 PY 1998 VL 25 IS 15 BP 3019 EP 3022 DI 10.1029/98GL00704 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 108WZ UT WOS:000075289900066 ER PT J AU Hofmeister, EP Shin, AY AF Hofmeister, EP Shin, AY TI The role of prophylactic fasciotomy and medical treatment in limb ischemia and revascularization SO HAND CLINICS LA English DT Article ID FREE-RADICAL SCAVENGERS; SKELETAL-MUSCLE; REPERFUSION INJURY; ISOLATED NEUTROPHILS; LIPID-PEROXIDATION; DEFEROXAMINE; RABBIT; DESFERRIOXAMINE; MYELOPEROXIDASE; PERMEABILITY AB Multiple studies have demonstrated that muscle poorly tolerates ischemia. When the ischemic state is unduly prolonged, the successfully replanted or revascularized limb undergoes deleterious biochemical reactions that cascade to vessel intimal damage, increased vessel permeability, and lowering of pH. The resultant tissue edema leads to increasing compartment pressures, which not only impede the recovery of function, but also can lead to irreversible muscle necrosis, increased risk of infection, and sepsis if not reversed in a timely fashion. The development of compartment syndrome jeopardizes not only the injured limb, but life itself secondary to the biochemical toxins produced by the ischemic extremity. A thorough understanding of the biochemistry of ischemia and reperfusion provides insight into the role of fasciotomy in the replanted or revascularized extremity. The scientific basis for fasciotomy in the revascularized or replanted limb is discussed as well as the potential "protective" role of pharmacologic agents in ischemic and reperfusion injury. C1 USN, Med Ctr, Dept Clin Invest, Div Hand & Microvasc Surg, San Diego, CA 92134 USA. USN, Med Ctr, Dept Orthopaed Surg, San Diego, CA 92134 USA. RP Shin, AY (reprint author), USN, Med Ctr, Dept Clin Invest, Div Hand & Microvasc Surg, San Diego, CA 92134 USA. OI Shin, Alexander/0000-0001-9658-8192 NR 54 TC 13 Z9 13 U1 1 U2 2 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0749-0712 J9 HAND CLIN JI Hand Clin. PD AUG PY 1998 VL 14 IS 3 BP 457 EP + PG 10 WC Orthopedics SC Orthopedics GA 119MG UT WOS:000075899800013 PM 9742424 ER PT J AU Townsend, JK Haraszti, Z Freebersyser, JA Devetsikiotis, M AF Townsend, JK Haraszti, Z Freebersyser, JA Devetsikiotis, M TI Simulation of rare events in communications networks SO IEEE COMMUNICATIONS MAGAZINE LA English DT Article AB Computer simulation is an important tool in the analysis and design of communications networks. In spite of the advances in computational power, using simulation to obtain rare event probabilities such as cell/packet loss or delay in networks still requires prohibitively long execution times. We provide an overview of importance sampling techniques and how they can be used to provide orders of magnitude speedup for many network problems. C1 N Carolina State Univ, Raleigh, NC 27695 USA. Off Naval Res, Arlington, VA 22217 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. RP Townsend, JK (reprint author), N Carolina State Univ, Raleigh, NC 27695 USA. NR 13 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 0163-6804 J9 IEEE COMMUN MAG JI IEEE Commun. Mag. PD AUG PY 1998 VL 36 IS 8 BP 36 EP 41 DI 10.1109/35.707815 PG 6 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 108VD UT WOS:000075285600003 ER PT J AU Crepeau, PJ AF Crepeau, PJ TI Classification of error locator polynomials for double error correcting BCH codes SO IEEE TRANSACTIONS ON COMMUNICATIONS LA English DT Article; Proceedings Paper CT Military Communications Conference CY OCT 21-24, 1996 CL MCLEAN, VIRGINIA DE BCH codes; decoding; error correction AB We give a complete classification of the error locator polynomials that occur in the Berlekamp decoding of double error correcting (DEC) Bose-Chaudhuri-Hocquenghem (BCH) codes. We present a new construction showing that all quadratic error locator polynomials produced by received vectors falling in the interstitial region between decoding spheres are illegitimate and have no roots. Furthermore, we show that a small subset of received vectors in the interstitial region produce cubic error locator polynomials that are illegitimate except for the correctable case of a triple error pattern with three equally spaced errors in the cyclic sense. C1 USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. RP Crepeau, PJ (reprint author), USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. NR 1 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 0090-6778 J9 IEEE T COMMUN JI IEEE Trans. Commun. PD AUG PY 1998 VL 46 IS 8 BP 977 EP 980 DI 10.1109/26.705389 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 111UZ UT WOS:000075457800002 ER PT J AU Solka, JL Marchette, DJ Wallet, BC Irwin, VL Rogers, GW AF Solka, JL Marchette, DJ Wallet, BC Irwin, VL Rogers, GW TI Identification of man-made regions in unmanned aerial vehicle imagery and videos SO IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE LA English DT Article DE region of interest identification; unmanned aerial vehicle; video processing ID ADAPTIVE MIXTURES; COMPUTATION AB This paper details recent work in our group on the use of low-level features for the identification of man-made regions in unmanned aerial vehicle (UAV) imagery. The feature sets that we have examined include classical statistical features such as the coefficient of variation in a window about a pixel, locally computed fractal dimension, and fractal dimension computed in the presence of wavelet boundaries. We will discuss these techniques of feature extraction along with our approach to the classification of the features. Our classification work has focused on the use of a new semiparametric probability density estimation technique. In addition, we will present classification results for region of interest identification based on a Set of test images from a recent UAV test flight. C1 USN, Ctr Surface Warfare, Adv Computat Technol Grp, Dahlgren Div, Dahlgren, VA 22448 USA. RP Solka, JL (reprint author), USN, Ctr Surface Warfare, Adv Computat Technol Grp, Dahlgren Div, Code B10,17320 Dahlgren Rd, Dahlgren, VA 22448 USA. EM jsolka@nswc.navy.mil NR 15 TC 24 Z9 31 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0162-8828 EI 1939-3539 J9 IEEE T PATTERN ANAL JI IEEE Trans. Pattern Anal. Mach. Intell. PD AUG PY 1998 VL 20 IS 8 BP 852 EP 857 DI 10.1109/34.709607 PG 6 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 110GT UT WOS:000075372700008 ER PT J AU Davis, J Deeney, C AF Davis, J Deeney, C TI Z-pinch plasmas SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Editorial Material C1 USN, Res Lab, Washington, DC 20375 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Davis, J (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 2 TC 0 Z9 0 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD AUG PY 1998 VL 26 IS 4 BP 1066 EP 1067 DI 10.1109/TPS.1998.725134 PG 2 WC Physics, Fluids & Plasmas SC Physics GA 125FN UT WOS:000076226900001 ER PT J AU Commisso, RJ Apruzese, JP Black, DC Boller, JR Moosman, B Mosher, D Stephanakis, SJ Weber, BV Young, FC AF Commisso, RJ Apruzese, JP Black, DC Boller, JR Moosman, B Mosher, D Stephanakis, SJ Weber, BV Young, FC TI Results of radius scaling experiments and analysis of neon K-shell radiation data from an inductively driven Z-pinch SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE inductive energy storage; plasma pinch; X-ray production ID RAYLEIGH-TAYLOR INSTABILITY; PLASMA OPENING SWITCH; ALUMINUM-WIRE-ARRAY; X-RAY-EMISSION; GAS-PUFF; IMPLOSIONS; LOADS; POWER; PREIONIZATION; SUPPRESSION AB The K-shell radiated energy (yield) from neon Z-pinch implosions with annular, gas-puff nozzle radii of 1, 1.75, and 2.5 cm was measured for implosion times from 50 to 300 ns while systematically keeping the implosion kinetic energy nearly constant. The implosions were driven by the Hawk inductive-storage generator at the 0.65-MA level. Initial neutral-neon density distributions from the nozzles were determined with laser interferometry. Measured yields are compared with predictions from zero-dimensional (0-D) scaling models of ideal, one-dimensional (1-D) pinch behavior to both benchmark the scaling models, and to determine their utility for predicting K-shell yields for argon implosions of 200 to >300 ns driven by corresponding currents of 4 to 9 MA, such as envisioned for the DECADE QUAD. For all three nozzles, the 0-D models correctly predict the Z-pinch mass for maximum yield. For the 1- and 1.75-cm radius nozzles, the scaling models accurately match the measured yields if the ratio of initial to final radius (compression ratio) is assumed to be 8:1, For the 2.5-cm radius nozzle, the measured yields are only one-third of the predictions. Analysis of K-shell spectral measurements suggest that as much as 70% (50%) of the imploded mass is radiating in the K-shell for the 1-cm (1.75-cm) radius nozzle, That fraction is only 10% for the 2.5-cm radius nozzle, The 0-D scaling models are useful for predicting 1-D-like K-shell radiation yields (better than a factor-of-two accuracy) when a nominal (approximate to 10:1) compression ratio is assumed. However, the compression ratio assumed in the models is only an "effective" quantity, so that further interpretations based on the 0-D analysis require additional justification. The lower-than-predicted yield for the 2.5-cm radius nozzle is associated with larger radius and not with longer implosion time, and is probably a result of two-dimensional effects. C1 USN, Res Lab, Div Plasma Phys, Pulsed Power Phys Branch, Washington, DC 20375 USA. JAYCOR Inc, Vienna, VA 22102 USA. RP Commisso, RJ (reprint author), USN, Res Lab, Div Plasma Phys, Pulsed Power Phys Branch, Washington, DC 20375 USA. EM commisso@suzie.nrl.navy.mil NR 50 TC 26 Z9 30 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD AUG PY 1998 VL 26 IS 4 BP 1068 EP 1085 DI 10.1109/27.725135 PG 18 WC Physics, Fluids & Plasmas SC Physics GA 125FN UT WOS:000076226900002 ER PT J AU Whitney, KG Thornhill, JW AF Whitney, KG Thornhill, JW TI The influence of temperature gradients on the distribution of axial current in a large current Z-pinch implosion SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE beta(A) conductivities; one-dimensional magnetohydrodynamics; Z-pinch current profiles ID ALUMINUM-WIRE-ARRAY; EMISSION AB General algebraic expressions for the tensor electrical conductivity and heat conductivity are presented that are needed in one-dimensional (I-D) magnetohydrodynamic modeling of Z-pinch implosions. The expressions contain both the ionization state and the magnetic field dependence of these quantities and generalize Braginskii's results. The ionization dependence is important in any description of a Z-pinch's implosion dynamics, since substantial ionization occurs during the course of the implosion. The tensor character of the electrical conductivity implies that axial currents are generated by radial temperature gradients in the presence of a Z-pinch's magnetic field. We find that these currents make contributions to the full current distribution that are comparable to the electric field generated currents. The effect of these temperature gradients on the full current distribution in a 1-D Z-pinch implosion is calculated by using the derived formulas for the electrical resistivity. The implosion we model is similar to the one that was found in an analysis of time-resolved X-ray data to give a good representation of the temperature gradients generated in a 90-wire, aluminum shot on the Saturn generator at the Sandia National Laboratories. [Phys, Rev. E 56, 3540 (1997)], In the calculation, we find that, on axis, gradient-driven currents limit total current flow near the front surface of the plasma, causing a much larger current to flow in the plasma interior than otherwise and reducing the temperature gradients that would be calculated in their absence. The gradient structure of the plasma is changed because the modified current distribution produces a different set of j x B forces, which act on the plasma. These nonlinear magnetic field effects persist during the plasma's expansion from the axis following peak compression. C1 USN, Res Lab, Div Plasma Phys, Radiat Hydrodynam Branch, Washington, DC 20375 USA. RP Whitney, KG (reprint author), USN, Res Lab, Div Plasma Phys, Radiat Hydrodynam Branch, Washington, DC 20375 USA. EM whitney@ppd.nrl.navy.mil NR 16 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD AUG PY 1998 VL 26 IS 4 BP 1168 EP 1178 DI 10.1109/27.725147 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 125FN UT WOS:000076226900014 ER PT J AU Apruzese, JP Thornhill, JW Whitney, KG Davis, J Deeney, C Nash, TJ Spielman, RB L'Eplattenier, P LePell, PD Failor, BH Riordan, JC Whitton, BA Yadlowsky, EJ Hazelton, RC Moschella, JJ AF Apruzese, JP Thornhill, JW Whitney, KG Davis, J Deeney, C Nash, TJ Spielman, RB L'Eplattenier, P LePell, PD Failor, BH Riordan, JC Whitton, BA Yadlowsky, EJ Hazelton, RC Moschella, JJ TI Spectroscopic diagnosis of the temperature profile of an Al : Mg Z-pinch SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE plasma measurements; plasma pinch; spectral analysis; X-ray measurements; X-ray production; X-ray spectroscopy ID ALUMINUM-WIRE-ARRAY; X-RAY-EMISSION; GAS-PUFF; HIGH-POWER; PLASMAS; IMPLOSION; RADIATION; SPECTRA; ARGON; NEON AB We consider the question of how the temperature profile of a Z-pinch plasma can be determined and/or constrained by the requirement that its observed ii-shell spectrum be replicated. As a case study we employ spatially integrated, time-resolved K-shell data obtained from the implosion of 30-wire Al:Mg alloy arrays on the Saturn driver at Sandia National Laboratories. Given the measured pinch size, its K-shell power and line intensities are compared with the predictions of a collisional-radiative-equilibrium plasma model whose temperature profile is varied in seeking agreement with the data. The Al data rules out a large range of possible temperature profiles, but two quite different temperature distributions can both match the measurements. These are: a uniform temperature, or, one with a sharply dropping temperature near the pinch outer edge. However, the measured ratio of the Mg a resonance lines to those of Al, even though time-integrated, excludes the possibility of a uniform temperature distribution. C1 USN, Res Lab, Div Plasma Phys, Radiat Hydrodynam Branch, Washington, DC 20375 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Maxwell Phys Int, San Leandro, CA 94577 USA. HY Tech Res Corp, Radford, VA 24141 USA. RP Apruzese, JP (reprint author), USN, Res Lab, Div Plasma Phys, Radiat Hydrodynam Branch, Washington, DC 20375 USA. EM davisj@ppdu.nrl.navy.mil NR 21 TC 12 Z9 14 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD AUG PY 1998 VL 26 IS 4 BP 1185 EP 1191 DI 10.1109/27.725149 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 125FN UT WOS:000076226900016 ER PT J AU Davis, J Clark, RW Giuliani, JL Thornhill, JW Deeney, C AF Davis, J Clark, RW Giuliani, JL Thornhill, JW Deeney, C TI Radiative characteristics of pulsed power driven Z-pinch aluminum plasmas SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE magnetohydrodynamics; pulse power systems; X-ray spectroscopy ID WIRE-ARRAY AB In this paper, we study the dynamics of a massive aluminum Z-pinch plasma load and evaluate its performance as a soft X-ray radiator. A radiation hydrodynamic model self-consistently driven by a circuit describes the dynamics, Comparisons are made for the K- and L-shell soft X-ray emission as a function of the ionization dynamic model. The ionization dynamic models are represented by: 1) a time-dependent nonequilibrium (NEQ) model, 2) a collisional radiative equilibrium (CRE) model, and 3) a local thermodynamic equilibrium (LTE) model. For all three scenarios the radiation is treated 1) in the free streaming optically thin approximation where the plasma is treated as a volume emitter and 2) in the optically thick regime where the opacity for the lines and continuum is self-consistently calculated online and the radiation is transported through the plasma. Each simulation is carried out independently to determine the sensitivity of the implosion dynamics to the ionization and radiation model, i.e., how the ionization dynamic model affects the radiative yield and emission spectra, Results are presented for the L- and K-shell radiation yields and emission spectra as a function of photon energy from 10 eV to 10 keV, Also, departure coefficients from LTE are presented for selected levels and ionization stages. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Davis, J (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 12 TC 1 Z9 1 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD AUG PY 1998 VL 26 IS 4 BP 1192 EP 1201 DI 10.1109/27.725150 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 125FN UT WOS:000076226900017 ER PT J AU Manheimer, WM Ewell, GW AF Manheimer, WM Ewell, GW TI Electrostatic and parametric cyclotron wave amplifiers SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE cyclotron wave amplifiers; low noise amplifiers; parametric amplifiers AB Cyclotron wave amplifiers were invented in both the United States and Russia in the late 1950's. While work in the United States was dropped in favor of solid state amplifiers, their development and use continues in Russia. This paper develops the basic theory of these amplifiers for Western scientists and engineers, specifies the performance of several sample commercially produced items, and compares performance of these devices with theory. Applications of devices to real world radar systems and the resulting advantages are briefly discussed. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Georgia Tech Res Inst, Syst Dev Lab, Atlanta, GA 30332 USA. RP Manheimer, WM (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 51 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD AUG PY 1998 VL 26 IS 4 BP 1282 EP 1296 DI 10.1109/27.725161 PG 15 WC Physics, Fluids & Plasmas SC Physics GA 125FN UT WOS:000076226900028 ER PT J AU Yun, XP Sarkar, N AF Yun, XP Sarkar, N TI Unified formulation of robotic systems with holonomic and nonholonomic constraints SO IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION LA English DT Article DE holonomic constraints; nonholonomic constraints ID DIFFERENTIAL-ALGEBRAIC EQUATIONS; FEEDBACK STABILIZATION; MECHANICAL SYSTEMS; NUMERICAL-SOLUTION; RIGID BODIES; MOTION; KINEMATICS; DYNAMICS; MANIPULATION; CONTACT AB Many robotic systems are subject to nonholonomic as well as holonomic constraints. Rolling contact between two rigid bodies is a typical example of such a system. In this study, a unified state space formulation of robotic systems subject to both holonomic and nonholonomic constraints is presented. The position-level holonomic constraints are first replaced by a set of velocity-level constraint equations that asymptotically converge to the original holonomic constraints. saving represented both holonomic and nonholonomic constraints in a common form, a state space representation of the constrained systems is then developed. A numerical algorithm for implementing the state space representation is also described. The proposed formulation eliminates the need to solve holonomic constraints either analytically or numerically, and ensures that holonomic constraints are always satisfied, particularly in computer simulations. The formulation makes it possible to treat systems with holonomic constraints, with nonholonomic constraints, or with both holonomic and nonholonomic constraints in a unified framework. Two examples are presented to illustrate the application of the unified formulation. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. Univ Hawaii Manoa, Dept Mech Engn, Honolulu, HI 96822 USA. RP USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. EM yun@ece.nps.navy.mil; sarkar@wiliki.eng.hawaii.edu NR 56 TC 60 Z9 63 U1 1 U2 4 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 AUG PY 1998 VL 14 IS 4 BP 640 EP 650 DI 10.1109/70.704238 PG 11 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA 104PW UT WOS:000075023800015 ER PT J AU Salkowski, CA Detore, G Franks, A Falk, MC Vogel, SN AF Salkowski, CA Detore, G Franks, A Falk, MC Vogel, SN TI Pulmonary and hepatic gene expression following cecal ligation and puncture: Monophosphoryl lipid A prophylaxis attenuates sepsis-induced cytokine and chemokine expression and neutrophil infiltration SO INFECTION AND IMMUNITY LA English DT Article ID TUMOR-NECROSIS-FACTOR; MESSENGER-RNA EXPRESSION; COLONY-STIMULATING FACTOR; INTERCELLULAR-ADHESION MOLECULE-1; MACROPHAGE INFLAMMATORY PROTEIN-2; INTERFERON-GAMMA-PRODUCTION; NITRIC-OXIDE SYNTHASE; GRAM-NEGATIVE SEPSIS; IFN-GAMMA; ENDOTOXIN TOLERANCE AB Polymicrobial sepsis induced by cecal ligation and puncture (CLP) reproduces many of the pathophysiologic features of septic shock In this study, we demonstrate that mRNA for a broad range of pro- and anti-inflammatory cytokine and chemokine genes are temporally regulated after CLP in the lung and liver. We also assessed whether prophylactic administration of monophosphoryl lipid A (MPL), a nontoxic derivative of lipopolysaccharide (LPS) that induces endotoxin tolerance and attenuates the sepsis syndrome in mice after CLP, would alter tissue-specific gene expression post-CLP, Levels of pulmonary interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-alpha), granulocyte colony-stimulating factor (G-CSF), IL-1 receptor antagonist (IL-1ra), and IL-10 mRNA, as well as hepatic IL-1 beta, IL-6, gamma interferon (IFN-gamma), G-CSF, inducible nitric oxide synthase, and IL-10 mRNA, were reduced in MPL-pretreated mice after CLP compared to control mice. Chemokine mRNA expression was also profoundly mitigated in MPL-pretreated mice after CLP. Specifically, levels of pulmonary and hepatic macrophage inflammatory protein 1 alpha (MIP-1 alpha), MIP-1 beta, MIP-2, and monocyte chemoattractant protein-1 (MCP-1) mRNA, as well as hepatic IFN-gamma-inducible protein 10 and KC mRNA, were attenuated in MPC-pretreated mice after CLP, Attenuated levels of IL-6, TNF-alpha, MCP-1, MIP-1 alpha, and MIP-2 in serum also were observed in MPG-pretreated mice after CLP. Diminished pulmonary chemokine mRNA production was associated with reduced neutrophil margination and pulmonary myeloperoxidase activity. These data suggest that prophylactic administration of MPL mitigates the sepsis syndrome by reducing chemokine production and the recruitment of inflammatory cells into tissues, thereby attenuating the production of proinflammatory cytokines. C1 Uniformed Serv Univ Hlth Sci, Dept Immunol & Microbiol, Bethesda, MD 20814 USA. USN, Med Res Inst, Resuscitat Med Program, Bethesda, MD 20889 USA. RP Vogel, SN (reprint author), Uniformed Serv Univ Hlth Sci, Dept Immunol & Microbiol, 4301 Jones Bridge Rd, Bethesda, MD 20814 USA. EM vogel@usuhsb.usuhs.mil FU NIAID NIH HHS [R37 AI018797, R01 AI018797, AI-18797, R56 AI018797] NR 72 TC 104 Z9 109 U1 0 U2 2 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0019-9567 J9 INFECT IMMUN JI Infect. Immun. PD AUG PY 1998 VL 66 IS 8 BP 3569 EP 3578 PG 10 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 103TJ UT WOS:000074973700012 PM 9673235 ER PT J AU Robinson, GE AF Robinson, GE TI Defensive democratization in Jordan SO INTERNATIONAL JOURNAL OF MIDDLE EAST STUDIES LA English DT Article; Proceedings Paper CT 28th Annual Meeting of the Middle-East-Studies-Association-of-North-America CY NOV 19-22, 1994 CL PHOENIX, ARIZONA SP Middle E Studies Assoc N Amer C1 USN, Postgrad Sch, Monterey, CA 93943 USA. Univ Calif Berkeley, Ctr Middle Eastern Studies, Berkeley, CA 94720 USA. RP Robinson, GE (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 51 TC 30 Z9 30 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0020-7438 J9 INT J MIDDLE E STUD JI Int. J. Middle East Stud. PD AUG PY 1998 VL 30 IS 3 BP 387 EP 410 PG 24 WC Area Studies SC Area Studies GA 108TY UT WOS:000075282600005 ER PT J AU Roy, DNG Warner, J Couchman, LS Shirron, J AF Roy, DNG Warner, J Couchman, LS Shirron, J TI Inverse obstacle transmission problem in acoustics SO INVERSE PROBLEMS LA English DT Article ID SCATTERING; DOMAIN; TOMOGRAPHY; BOUNDARY AB The results of inverse scattering of plane acoustic waves from penetrable, homogeneous acoustic obstacles in two space dimensions are reported. The shape and the material parameters of the obstacles are recovered from both 360 degrees and limited-aperture, far-field patterns in the presence of random noise. The forward problem is solved via a combination of shape differentiation of the scattered field and the Pade approximation. Not being an integral equation based approach, the method is free of the non-uniqueness problem associated with the interior eigenvalues of the scatterer. Moreover, it is shown that all necessary scattering and Jacobian calculations need to be performed only with respect to a circle of a fixed radius. In addition, by the construction of the forward solution, the objective unction to be minimized for inversion does not contain terms arising from the boundary conditions. This, along with the fact that the domain of calculations remains invariant to the stage of iteration, results in a substantial simplification in the implementation of a Gauss-Newton type of inversion procedure which is used here. Finally, the method is illustrated with several transmission obstacles of various shapes and with different initial conditions. C1 SFA Inc, Landover, MD 20785 USA. USN, Res Lab, Phys Acoust Branch, Washington, DC 20375 USA. RP Roy, DNG (reprint author), SFA Inc, 1401 McCormick Dr, Landover, MD 20785 USA. NR 30 TC 6 Z9 6 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0266-5611 J9 INVERSE PROBL JI Inverse Probl. PD AUG PY 1998 VL 14 IS 4 BP 903 EP 929 DI 10.1088/0266-5611/14/4/010 PG 27 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 113LE UT WOS:000075551800010 ER PT J AU Turk, J Vivekanandan, J Lee, T Durkee, P Nielsen, K AF Turk, J Vivekanandan, J Lee, T Durkee, P Nielsen, K TI Derivation and applications of near-infrared cloud reflectances from GOES-8 and GOES-9 SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID RADIATION MEASUREMENTS; SOLAR-RADIATION; RETRIEVAL; IMAGERY; SURFACE; FOG AB Recent deployments of the National Oceanic and Atmospheric Administration (NOAA) Geostationary Operational Environmental Satellites (GOES-8 and -9) include full-time 3.9-mu m imaging capabilities. This shortwave (near infrared) channel has been available at 3.7 mu m on the Advanced Very High Resolution Radiometer (AVHRR) instrument aboard the NOAA polar-orbiting satellite systems. In this spectral region, daytime satellite-observed radiances include contributions from both the reflected solar radiation and the emitted thermal emission. In particular, typical stratus and fog clouds posess near-infrared emissivities less than unity, which requires special processing to account for the angular dependence of the solar reflection. In this paper, a side-by-side comparison of time-coincident GOES-and AVHRR-derived near-infrared cloud reflectance is carried out in order to demonstrate the capability of GOES-8 and -9 in both identifying and characterizing the microphysics of stratus and fog clouds during the daytime. The authors first present the mathematical formalism and then apply the technique to extract the near-infrared reflectances from GOES-8 and -9 data. The technique is applicable for operational usage and requires a lookup table to account for the continuously changing sun-satellite viewing geometry. Near-infrared cloud reflectances are extracted from coincident GOES-9 and AVHRR data from both NOM-14 and -12 for different times of day and are verified against theoretical reflectances derived from radiative transfer theory and previously published results. A retrieval of the cloud drop size distribution effective radius is demonstrated on satellite data along coastal California during the summer of 1996. C1 USN, Res Lab, Marine Meteorol Div, Monterey, CA 93943 USA. RP Turk, J (reprint author), USN, Res Lab, Marine Meteorol Div, 7 Grace Hopper Ave, Monterey, CA 93943 USA. NR 17 TC 11 Z9 13 U1 0 U2 0 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 AUG PY 1998 VL 37 IS 8 BP 819 EP 831 DI 10.1175/1520-0450(1998)037<0819:DAAONI>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 106EK UT WOS:000075116800005 ER PT J AU Mason, W Waterman, JR AF Mason, W Waterman, JR TI Electrical properties of extremely low doped GaSb Schottky diodes SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MOLECULAR-BEAM EPITAXY; DEEP LEVELS; SPECTROSCOPY AB This article presents capacitance-voltage (C/V), current-voltage (J/V), and deep level spectroscopy (DLTS) measurements on Al/GaSb Schottky diodes; the GaSb was doped n type using a Ga2Te3 source. We found a net doping density of 1.71x10(15) cm(-3) and a barrier height of 0.436 eV from the C/V measurements. At room temperature, the J/V characteristics gave an ideality factor of 1.2 and an apparent barrier height of 0.48 eV. DLTS measurements showed a single peak in the capacitance at about 80 K, giving an activation energy of 0.219 eV. This value is comparable to the value seen in Te-doped GaSb Schottky diodes doped with other sources and in undoped GaSb. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Washington, DC 20375 USA. RP Mason, W (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 15 TC 7 Z9 7 U1 0 U2 3 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 AUG 1 PY 1998 VL 84 IS 3 BP 1426 EP 1429 DI 10.1063/1.368177 PG 4 WC Physics, Applied SC Physics GA 108YT UT WOS:000075294600043 ER PT J AU Kaihatu, JM Handler, RA Marmorino, GO Shay, LK AF Kaihatu, JM Handler, RA Marmorino, GO Shay, LK TI Empirical orthogonal function analysis of ocean surface currents using complex and real-vector methods SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID WIND; DYNAMICS; RADAR AB Empirical orthogonal function (EOF) analysis has been widely used in meteorology and oceanography to extract dominant modes of behavior in scalar and vector datasets. For analysis of two-dimensional vector fields, such as surface winds or currents, use of the complex EOF method has become widespread. In the present paper, this method is compared with a real-vector EOF method that apparently has previously been unused for current or wind fields in oceanography or meteorology. It is shown that these two methods differ primarily with respect to the concept of optimal representation. Further, the real-vector analysis can easily be extended to three-dimensional vector fields, whereas the complex method cannot. To illustrate the differences between approaches. both methods are applied to Ocean Surface Current Radar data collected off Cape Hatteras, North Carolina, in June and July 1993. For this dataset, while the complex analysis "converges" in fewer modes, the real analysis is better able to isolate flows with wide cross-shelf structures such as tides. C1 USN, Res Lab, Div Oceanog, Stennis Space Ctr, MS 39529 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Dept Meteorol & Phys Oceanog, Miami, FL 33149 USA. RP Kaihatu, JM (reprint author), USN, Res Lab, Div Oceanog, Code 7320, Stennis Space Ctr, MS 39529 USA. EM kaihatu@taurus.nrlsc.navy.mil RI Kaihatu, James/H-7561-2016 OI Kaihatu, James/0000-0002-9277-6409 NR 28 TC 59 Z9 61 U1 1 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD AUG PY 1998 VL 15 IS 4 BP 927 EP 941 DI 10.1175/1520-0426(1998)015<0927:EOFAOO>2.0.CO;2 PG 15 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 107WK UT WOS:000075233800007 ER PT J AU Sobel, DO Goyal, D Ahvazi, B Yoon, JW Chung, YH Bagg, A Harlan, DM AF Sobel, DO Goyal, D Ahvazi, B Yoon, JW Chung, YH Bagg, A Harlan, DM TI Low dose poly I : C prevents diabetes in the diabetes prone BB rat SO JOURNAL OF AUTOIMMUNITY LA English DT Article DE BB rat; poly I : C; IDDM; cytokines; immunoregulatory cell ID TUMOR-NECROSIS-FACTOR; SUPPRESSOR T-CELL; NOD MICE; MONOCLONAL-ANTIBODIES; INTERFERON-GAMMA; FREUND ADJUVANT; LYMPHOCYTES-T; FACTOR-ALPHA; TNF-ALPHA; EXPRESSION AB Poly I:C, an inducer of IFN-alpha and other cytokines, has been used to study the development of diabetes in both the BioBreeding (BB) diabetes prone rat and non-obese diabetic (NOD) mouse animal models of insulin-dependent diabetes mellitus (IDDM). Surprisingly, poly I:C accelerates the disease in the BB rat while inhibiting it in the NOD mouse. Since cytokines can have dose related opposing effects on immune responses, we hypothesized that the paradoxical effect of polyinosinic polycytidylic acid (poly I:C) on diabetes in the two animal models is dose related. Accordingly, we compared the incidence of diabetes and degree of insulitis in diabetes prone BB rats administered saline and poly I:C at doses (0.05 mu g/g body weight and 0.1 mu g/g body weight) up to 100-fold lower than doses (poly5 mu g/g) previously found to accelerate diabetes. In addition, the non-specific suppressor activity of mononuclear splenocytes from BB rats administered low dose (poly-0.05 mu g/g body weight), high dose (poly-5 mu g/g body weight), and saline were compared. The development of diabetes was inhibited in rats treated with each dose of poly I:C. The degree of insulitis in poly-I:C treated animals was also less severe. The total white blood cell count and proportion of RT6(+) T-cells and each T-cell subset were unaltered by poly I:C. When compared to splenocytes of control animals, splenocytes from poly I:C (0.05 mu g/g body weight) treated rats suppressed responder cell proliferation to concanavalin A and alloantigen. However, spleen cells from high dose poly-I:C did not suppress responder cell proliferation to alloantigen. In adoptive transfer studies, the administration of spleen cells from poly-0.05 treated rats decreased the development of diabetes in recipient BB rats. In vitro studies also demonstrated that poly-I:C inhibits the proliferative response of BB rat spleen cells to concanavalin A. The administration of poly-0.05, but not poly-5.0, decreased TNF-alpha mRNA and IL-10 mRNA content in spleen cells. We conclude that poly I:C, at a dose 100 times lower than that required to accelerate diabetes prevents the development of diabetes in BB rates by interfering with the development of insulitis. The induction of suppressor cell activity induced by low dose poly-I:C in vivo and the inhibition of T-cell responses by poly-I:C in vitro suggests that the diabetes sparing activity of poly I:C is mediated by augmented immunoregulatory cell activity. Further studies with poly I:C may be important in increasing our understanding of the pathogenesis of IDDM and provide a means to prevent it. (C) 1998 Academic Press. C1 Georgetown Univ, Sch Med, Washington, DC 20007 USA. USN, Med Res Inst, Bethesda, MD 20889 USA. Julia McFarlane Diabet Univ Calgary, Calgary, AB, Canada. RP Sobel, DO (reprint author), Georgetown Univ, Childrens Med Ctr, Div Pediat Endocrinol & Metab, 3800 Reservoir Rd NW, Washington, DC 20007 USA. NR 45 TC 44 Z9 45 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0896-8411 J9 J AUTOIMMUN JI J. Autoimmun. PD AUG PY 1998 VL 11 IS 4 BP 343 EP 352 DI 10.1006/jaut.1998.0203 PG 10 WC Immunology SC Immunology GA 118AR UT WOS:000075815500007 PM 9776712 ER PT J AU McClatchey, SK AF McClatchey, SK TI Intraocular lens calculator for childhood cataract SO JOURNAL OF CATARACT AND REFRACTIVE SURGERY LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Association-for-Pediatric-Ophthalmology-and-Strabismus CY APR, 1997 CL CHARLESTON, SOUTH CAROLINA SP Amer Assoc Pediat Ophthalmol & Strabismus ID OCULAR GROWTH; IMPLANTATION; CHILDREN; PSEUDOPHAKIA; EYES; MANAGEMENT; CAPSULE; POWER AB Purpose; To evaluate a computer program to predict the pseudophakic refraction of evaluate a com child at any age. Setting: A pediatric ophthalmology practice. Methods: A computer program was written for Windows 95 that,calculates the initial postoperative pseudophakic refraction of a child using Holiday's formula, given the axial length and keratometry readings. The logarithmic model was used. to predict the ultimate refraction at age 20 years and chart the predicted curve of retractive error with standard deviations. Results: The program provided a graph of a child's predicted pseudophakic refraction versus age that would allow the surgeon to dynamically view the effects of changing the intraocular lens (IOL) power. Conclusions: If pseudophakia and aphakia have the same effect on the growth of the child, this program should accurately predict the myopic shift of a pseudophakic 1 child. This could help guide the surgeon's choice of IOL power. C1 USN, Med Ctr, Dept Ophthalmol, San Diego, CA 92134 USA. RP McClatchey, SK (reprint author), USN, Med Ctr, Dept Ophthalmol, San Diego, CA 92134 USA. NR 23 TC 17 Z9 20 U1 0 U2 0 PU AMER SOC CATARACT REFRACTIVE SURGERY PI FAIRFAX PA 4000 LEGATO RD, SUITE 850, FAIRFAX, VA 22030 USA SN 0886-3350 J9 J CATARACT REFR SURG JI J. Cataract. Refract. Surg. PD AUG PY 1998 VL 24 IS 8 BP 1125 EP 1129 PG 5 WC Ophthalmology; Surgery SC Ophthalmology; Surgery GA 111AU UT WOS:000075415800021 PM 9719974 ER PT J AU Li, SH Huang, FL Feng, QP Liu, J Fan, SX McKenna, TM AF Li, SH Huang, FL Feng, QP Liu, J Fan, SX McKenna, TM TI Overexpression of protein kinase C alpha enhances lipopolysaccharide-induced nitric oxide formation in vascular smooth muscle cells SO JOURNAL OF CELLULAR PHYSIOLOGY LA English DT Article ID NF-KAPPA-B; L-ARGININE TRANSPORT; PHORBOL ESTERS; ENDOTHELIAL-CELLS; SYNTHASE ACTIVITY; MESSENGER-RNA; NO SYNTHASE; EXPRESSION; INDUCTION; RAT AB Our previous studies showed that lipopolysaccharide (LPS)-induced nitric oxide (NO) synthesis in cardiovascular tissues is attenuated by protein kinase C (PKC) inhibitors. In the current study, we identify a specific PKC isotype involved in the LPS signal transduction pathway that leads to NO formation in rat vascular smooth muscle cells (VSMC). VSMC were transfected with a mammalian expression vector containing a full length PKC alpha cDNA insert, and a stable transfectant overexpressing PKC alpha was obtained as evidenced by increased expression of PKC alpha mRNA and protein. In response to 100 ng/ml LPS stimulation, the PKC alpha transfectants showed a 1.8-fold increase in PKC activity at 30 min and a twofold increase in NO production over 24 hr compared with cells transfected with control plasmids. The LPS-stimulated increase in NO synthesis in PKC alpha transfectants was blocked by the specific PKC alpha inhibitor Ga 6976. After 6 hr LPS treatment, PKC alpha-transfected and control cells showed equivalent increases in mRNA and protein for the inducible NO synthase. NO synthase activity of the cell extracts assayed in the presence of excess substrate and cofactors was not significantly different between PKC alpha-transfected and control cells after LPS stimulation. However, mRNA levels for GTP cyclohydrolase I, a key enzyme in (GR)-tetrahydro-L-biopterin synthesis, and cationic amino acid transporter-2, involved in L-arginine transport, was enhanced in cells overexpressing PKC alpha compared with control cells. These results suggest that PKC alpha plays an important role in LPS-induced NO formation and that a significant portion of this effect may be by means of enhanced substrate availability to the inducible nitric oxide synthase enzyme. (C) 1998 Wiley-Liss, Inc. C1 NICHHD, Endocrinol & Reprod Res Branch, NIH, Bethesda, MD 20892 USA. USN, Res Inst, Resuscitat Med Program, Bethesda, MD USA. Univ Western Ontario, Dept Pharmacol & Toxicol, London, ON, Canada. RP Li, SH (reprint author), John P Robarts Res Inst, Vasc Biol Grp, 100 Perth Dr, London, ON N6A 5K8, Canada. EM shli@rri.on.ca NR 49 TC 20 Z9 24 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 0021-9541 J9 J CELL PHYSIOL JI J. Cell. Physiol. PD AUG PY 1998 VL 176 IS 2 BP 402 EP 411 DI 10.1002/(SICI)1097-4652(199808)176:2<402::AID-JCP19>3.0.CO;2-4 PG 10 WC Cell Biology; Physiology SC Cell Biology; Physiology GA ZV411 UT WOS:000074301900019 PM 9648928 ER PT J AU Twigg, ME Bennett, BR Magno, R AF Twigg, ME Bennett, BR Magno, R TI Morphological instability in InAs/GaSb heterostructures SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE morphological instability; molecular beam epitaxy; transmission electron microscopy; surface diffusion; compound semiconductors ID ENERGY ELECTRON-DIFFRACTION; MOLECULAR-BEAM EPITAXY; FREE SOLID FILMS; SURFACE-DIFFUSION; CRITICAL THICKNESS; GROWTH; SUPERLATTICES; INTERFACE; LAYER; GASB AB Using transmission electron microscopy, reflection electron microscopy, and atomic force microscopy, we have examined InAs layers grown on (1 0 0)GaSb using molecular beam epitaxy at temperatures ranging from 400 to 500 degrees C and at growth rates ranging from 0.03 to 0.09 monolayers/s. We have found that for lower growth rates and higher temperatures, nominally 8 monolayer InAs layers experience long-wavelength (>100 nm) small amplitude (similar to 1 nm) surface undulations. From linear stability theory, we find that the appearance of these undulations is consistent with large cation surface diffusion lengths that have been measured by other researchers using scanning reflection high-energy electron diffraction. It also appears, however, that there is no kinetic critical thickness for morphological instability of the InAs layer. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RP Twigg, ME (reprint author), USN, Res Lab, Div Elect Sci & Technol, 4555 Overlook Ave SW, Washington, DC 20375 USA. EM twigg@estd.nrl.navy.mil RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 41 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD AUG PY 1998 VL 191 IS 4 BP 651 EP 662 DI 10.1016/S0022-0248(98)00388-1 PG 12 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 115WE UT WOS:000075688600010 ER PT J AU Breitenstein, DS Shaw, CC AF Breitenstein, DS Shaw, CC TI Comparison of three tissue composition measurement techniques using digital mammograms - A signal-to-noise study SO JOURNAL OF DIGITAL IMAGING LA English DT Article ID DUAL-ENERGY MAMMOGRAPHY; BREAST-CANCER RISK; COMPUTED RADIOGRAPHY; IMAGING-SYSTEM; DENSITIES; CLASSIFICATION; DECOMPOSITION AB Tissue composition measurement may provide a quantitatively and physically meaningful method to objectively determine the "mammographic density" linked to breast cancer risk. A single energy hybrid (SEH) technique is described for measuring the tissue composition on a pixel-by-pixel basis with a single digital mammogram. Theoretical models were derived and used to compute signal-to-noise ratios (SNRs) in tissue composition measurement using the SEH method. The results were compared with those computed for measurements using the dual kVp and dual screen methods. SNRs were theoretically related to the pixel area, total unattenuated detector exposure and fluence spectra of the incident X-rays. SNRs were computed for measurement of the adipose tissue thickness for a 6 cm thick breast, consisting of 50% of adipose tissue and 50% of glandular tissue. Effects of kVp and prepatient filtration were studied by computing the SNRs for various kVps and filters and optimal kVps and filters are determined. The results showed that the SNRs obtained with the SEH method is an order of magnitude better than the dual kVp method, which, in turn, is an order of magnitude better than the dual screen method. When using the optimal kVp's and no prepatient filtration, the SNRs were computed to be 84.2, 13.2, and 2.0 for the SEH, dual kVp, and dual screen methods, respectively. Prepatient filtration can improve the SNR by as much as 35% for the dual kVp and dual screen techniques with reasonable tube loading factors(8-10). Copyright (C) 1998 by W.B. Saunders Company. C1 Univ Pittsburgh, Dept Radiol, Pittsburgh, PA 15261 USA. USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA USA. RP Shaw, CC (reprint author), Univ Pittsburgh, Dept Radiol, A439 Scaife Hall, Pittsburgh, PA 15261 USA. FU NCI NIH HHS [CA 51248] NR 33 TC 7 Z9 7 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 0897-1889 J9 J DIGIT IMAGING JI J. Digit. Imaging PD AUG PY 1998 VL 11 IS 3 BP 137 EP 150 PG 14 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 110MP UT WOS:000075385200005 PM 9718504 ER PT J AU Chakrabarti, K Bandyopadhyay, PK Barkyoumb, JH AF Chakrabarti, K Bandyopadhyay, PK Barkyoumb, JH TI Copper doped alkali halides for computed radiography and digital imaging SO JOURNAL OF DIGITAL IMAGING LA English DT Article; Proceedings Paper CT Annual Meeting of the Society-for-Computer-Applications-in-Radiology CY JUN 04-07, 1998 CL BALTIMORE, MD SP Soc Comp Applicat Radiol (SCAR), Amer Coll Radiol (ACR) ID THERMALLY STIMULATED LUMINESCENCE AB We report here the results of our x-ray fluorescence, photostimulated luminescence, and time resolved laser spectroscopy studies in KCl:Cu. This material seems to possess some desirable properties for being used as an imaging plate in computed radiography. This is a US government work. There are no restrictions on its use. C1 US FDA, Div Mammog Qual & Radiat Programs, Rockville, MD 20902 USA. Hendrix Coll, Conway, AR USA. USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD USA. RP Chakrabarti, K (reprint author), US FDA, Div Mammog Qual & Radiat Programs, 1350 Piccard Dr, Rockville, MD 20902 USA. NR 17 TC 2 Z9 3 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0897-1889 EI 1618-727X J9 J DIGIT IMAGING JI J. Digit. Imaging PD AUG PY 1998 VL 11 IS 3 SU 1 BP 174 EP 177 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 111NH UT WOS:000075443600052 PM 9735463 ER PT J AU Meier, RR Nicholas, AC Picone, JM Melendez-Alvira, DJ Ganguli, GI Reynolds, MA Roelof, EC AF Meier, RR Nicholas, AC Picone, JM Melendez-Alvira, DJ Ganguli, GI Reynolds, MA Roelof, EC TI Inversion of plasmaspheric EUV remote sensing data from the STP 72-1 satellite SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID HE-II 304-A; OUTER PLASMASPHERE; HELIUM; RADIATION; MAGNETOSPHERE; DENSITY; MODEL AB Observations of the extreme ultraviolet emission of helium ions at 30.4 nm can be used to study the global shape of the plasmasphere and its dynamical response to geomagnetic forcing. In order to retrieve number densities of plasmaspheric He+ from such observations, we have developed a new inversion technique based on discrete inverse theory, which uses the optical data to optimize a parameterized model of the He+ distribution. We apply this inversion technique to several orbits of data obtained from the Naval Research Laboratory extreme ultraviolet photometric experiment launched on the STP 72-1 satellite in October 1972. The inversion is limited to nighttime conditions where contamination from the topside ionosphere is minimal and where a simple parameterization of the He+ number density is applicable. We obtain excellent fits to the data; however, some of the retrieved model parameters have large uncertainties due to inadequate sampling of the plasmasphere. Our study shows that improved sampling using observations from different locations and view directions would significantly enhance the accuracy of the retrieved model parameters. Using a newly developed three-dimensional imaging tool to visualize the plasmaspheric regions being sampled remotely, we demonstrate that emission features observed from two of the STP 72-1 orbits originate beyond the plasmasphere. Estimated number densities of this feature are roughly consistent with observations of cold plasma seen at geosynchronous orbit by in situ experiments. C1 USN, EO Hulburt Ctr Space Res, Res Lab, Washington, DC 20375 USA. USN, Div Plasma Phys, Res Lab, Washington, DC 20375 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Praxis Inc, Alexandria, VA USA. RP Meier, RR (reprint author), USN, EO Hulburt Ctr Space Res, Res Lab, Code 7640, Washington, DC 20375 USA. RI Meier, Robert/G-4749-2014 OI Meier, Robert/0000-0001-8497-7115 NR 38 TC 13 Z9 13 U1 0 U2 2 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 AUG 1 PY 1998 VL 103 IS A8 BP 17505 EP 17518 DI 10.1029/98JA01175 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 107BV UT WOS:000075186700025 ER PT J AU Baird, JK Masbar, S Basri, H Tirtokusumo, S Subianto, B Hoffman, SL AF Baird, JK Masbar, S Basri, H Tirtokusumo, S Subianto, B Hoffman, SL TI Age-dependent susceptibility to severe disease with primary exposure to Plasmodium falciparum SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID MALARIA; MORTALITY AB This study investigated the incidence of severe disease following primary exposure to Plasmodium falciparum by nonimmune children and adults in Irian Jaya, Indonesia. Four months after arrival, the cross-sectional prevalence of P, falciparum was 72%, and the monthly cumulative incidence of clinical diagnoses of malaria was 81%. Delirium or unconsciousness prompted evacuation to the hospital. Records of emergency evacuation of persons with a clinical diagnosis of malaria revealed an incidence density among adults (>15 years) of 1.34 events/person-year in the third month, whereas the rate in children remained stable at similar to 0.25 events/person-year (relative risk = 4.51, 95% confidence interval [CI] = 1.94-11), Through the first 6 months of exposure, 23.2% of adults were evacuated to the hospital with a diagnosis of malaria compared with 8.6% of children (relative risk = 2.7, 95% CI = 1.9-3.8). In this population with relatively few infants or people of advanced age, the risk of severe disease following primary exposure to P. falciparum increased with age. C1 USN, Med Res Inst, Malaria Program, Rockville, MD 20852 USA. USN, Med Res Unit 2, Jakarta, Indonesia. DINAS Kesehatan, Prov Hlth Serv, Abebura, Irian Jaya, Indonesia. RP Baird, JK (reprint author), USN, Med Res Inst, Malaria Program, 12300 Washington Ave, Rockville, MD 20852 USA. NR 15 TC 44 Z9 45 U1 0 U2 1 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 AUG PY 1998 VL 178 IS 2 BP 592 EP 595 PG 4 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 103JA UT WOS:000075153000047 PM 9697752 ER PT J AU Zanoria, ES Watkins, TR Breder, K Riester, L Bashkansky, M Reintjes, J Sun, JG Ellingson, WA Blau, PJ AF Zanoria, ES Watkins, TR Breder, K Riester, L Bashkansky, M Reintjes, J Sun, JG Ellingson, WA Blau, PJ TI Assessment of techniques for characterizing the surface quality of ground silicon nitride SO JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE LA English DT Article DE grinding; silicon nitride; surface characterization; surface wear ID SUBSURFACE DEFECT DETECTION; RESIDUAL-STRESS; CERAMICS; DAMAGE AB This study evaluates techniques used to detect and quantify the extent of surface and subsurface damage in ground silicon nitride, Specimens of two differently ground surfaces of a hot isostatically pressed (HIP) silicon nitride, commercially designated as GS-44, were subjected to six types of analyses, namely mechanical stylus profiling, atomic force microscopy, point-counting analysis of fragmentation pits, laser-light scattering, optical gating, and grazing incidence x-ray diffraction (GIXD), The results of these investigations are compared and discussed. The techniques providing the dearest correlations with grinding conditions were mechanical stylus roughness, fragmentation analysis, and GIXD (residual stress conditions). Those that exhibited some correlation but appear to require more work to develop a reliable evaluation method were laser scattering and optical gating, Atomic force microscopy was useful, but not as a routine investigative tool for quality control in ceramic machining. The techniques that appear to have the most near-term potential for routine use are fragmentation analysis and optical gating, Laser-based optical scattering exhibits potential for routine application, but, more development is needed for its commercialization. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. USN, Res Lab, Washington, DC 20375 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Zanoria, ES (reprint author), Caterpillar Inc, PPG, Peoria, IL 61656 USA. RI Watkins, Thomas/D-8750-2016 OI Watkins, Thomas/0000-0002-2646-1329 NR 26 TC 2 Z9 2 U1 0 U2 0 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 AUG PY 1998 VL 7 IS 4 BP 533 EP 547 DI 10.1361/105994998770347693 PG 15 WC Materials Science, Multidisciplinary SC Materials Science GA 106DW UT WOS:000075115500013 ER PT J AU Cooper, KP Slebodnick, PL Lucas, KE Hogan, EA AF Cooper, KP Slebodnick, PL Lucas, KE Hogan, EA TI Microstructural inhomogeneities and sea water corrosion in laser-deposited Ti-6Al-4V alloy matrix/carbide particulate composite surfaces SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB Metal matrix/carbide particulate composite surface layers were produced on Ti-6Al-4V alloy samples by injecting metal carbide particles into laser-melted surfaces followed by rapid solidification. Hard, wear-resistant surfaces were produced on a strong alloy which normal ly has poor wear resistance. The corrosion behaviour of the composite surface was evaluated after a month's exposure to flowing sea water. A variety of solidification products was found in the laser-deposited surface layers, but corrosion was observed only in the carbide particulate phase in the WC-injected sample. No corrosion was observed in the TiC-injected sample nor in the Ti-6Al-4V base alloy. Corrosion in the WC-injected sample was related to the formation of a narrow interphase zone surrounding the particulate phase and a thin reaction zone on the surface of the particulate phase during solidification. The titanium-rich interphase zone formed a galvanic couple with the WC particulate. Crevice-type corrosion initiated at the interface between the two phases and proceeded into the particulate phase assisted by the reaction zone. Electrochemical test results revealed a high corrosion rate for the WC-injected sample and almost none for both the TiC-injected sample and the Ti-6A1-4V base alloy, confirming the microstructural observations. (C) 1998 Kluwer Academic Publishers. C1 USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. USN, Res Lab, Marine Corros Facil, Key W, FL 33040 USA. Geocenters Inc, Ft Washington, MD 20744 USA. RP Cooper, KP (reprint author), USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. NR 13 TC 10 Z9 11 U1 1 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD AUG 1 PY 1998 VL 33 IS 15 BP 3805 EP 3816 DI 10.1023/A:1004682915135 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 149DZ UT WOS:000077591000005 ER PT J AU Gaber, BP AF Gaber, BP TI Space, time and complexity in biomembrane models SO JOURNAL OF MOLECULAR GRAPHICS & MODELLING LA English DT Meeting Abstract C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1093-3263 J9 J MOL GRAPH MODEL JI J. Mol. Graph. PD AUG-DEC PY 1998 VL 16 IS 4-6 BP 289 EP 289 PG 1 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Computer Science, Interdisciplinary Applications; Crystallography; Mathematical & Computational Biology SC Biochemistry & Molecular Biology; Computer Science; Crystallography; Mathematical & Computational Biology GA 248ZK UT WOS:000083306500067 ER PT J AU Stenger, DA Hickman, JJ Bateman, KE Ravenscroft, MS Ma, W Pancrazio, JJ Shaffer, K Schaffner, AE Cribbs, DH Cotman, CW AF Stenger, DA Hickman, JJ Bateman, KE Ravenscroft, MS Ma, W Pancrazio, JJ Shaffer, K Schaffner, AE Cribbs, DH Cotman, CW TI Microlithographic determination of axonal/dendritic polarity in cultured hippocampal neurons SO JOURNAL OF NEUROSCIENCE METHODS LA English DT Article DE hippocampal neuron; neuronal polarity; self-assembled monolayers ID SELF-ASSEMBLED MONOLAYERS; GROWTH; EXPRESSION; SURVIVAL; GUIDANCE; SURFACES; NETWORKS; ADHESION; CELLS AB High resolution substrates, created using patterned self-assembled monolayers, are shown to direct axonal and dendritic process extension at the level of a single hippocampal neuron. Areas and dendrites were identified using morphological characteristics and immunocytochemical markers. Patterns were formed on glass coverslips from a co-planar monolayer of cell adhesive aminosilanes and non-adhesive fluorinated silanes. On patterned surfaces, the percentage of the total number of cells attached to the 0.71 mm(2) substrate field with compliance to the 25-mu m diameter 'somal adhesion site' reached 41 +/- 7% (mean +/- S.D., 428 cells counted). A total of 76 +/- 11% of cells that adhered to a somal attachment site developed a lone process greater than or equal to 100 mu m oriented in the direction of the continuous aminosilane pathway which was shown to express axonal markers, dells on either the fluorinated silane, which is non-permissive for neurite outgrowth, or localized on a:? aminosilane region only 5 mu m wide failed to extend major processes. This approach is amenable to a variety of industry standard fabrication techniques and may be used to study the role of fine scale spatial cues in neuronal development and synapse formation. (C) 1998 Elsevier Science B,V. All rights reserved. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. Sci Applicat Int Corp, Rockville, MD 20850 USA. NICHD, Dev Neurobiol Lab, NIH, Bethesda, MD 20892 USA. NINDS, Neurophysiol Lab, NIH, Bethesda, MD 20892 USA. Univ Calif Irvine, Inst Brain Aging & Dementia, Irvine, CA 92717 USA. RP Stenger, DA (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Code 6910, Washington, DC 20375 USA. RI Pancrazio, Joseph/M-3206-2015 OI Pancrazio, Joseph/0000-0001-8276-3690 NR 31 TC 119 Z9 122 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-0270 J9 J NEUROSCI METH JI J. Neurosci. Methods PD AUG 1 PY 1998 VL 82 IS 2 BP 167 EP 173 DI 10.1016/S0165-0270(98)00047-8 PG 7 WC Biochemical Research Methods; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA 113LV UT WOS:000075553200006 PM 9700689 ER PT J AU Ngai, KL Riande, E AF Ngai, KL Riande, E TI Proceedings of the third international discussion meeting on relaxations in complex systems - Vigo, Spain, 30 June 11 July 1997 - Preface SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Editorial Material C1 USN, Res Lab, Washington, DC 20375 USA. CSIC, Inst Ciencia Tecnol Polimeros, Madrid, Spain. RP Ngai, KL (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 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 AUG PY 1998 VL 235 BP VII EP VIII PG 2 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 118LC UT WOS:000075838800001 ER PT J AU Yagihara, S Yamada, M Asano, M Kanai, Y Shinyashiki, N Mashimo, S Ngai, KL AF Yagihara, S Yamada, M Asano, M Kanai, Y Shinyashiki, N Mashimo, S Ngai, KL TI Dielectric study on beta-relaxation process of tetramethyl-bisphenol-A polycarbonate SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 3rd International Discussion Meeting on Relaxations in Complex Systems CY JUN 30-JUL 11, 1997 CL VIGO, SPAIN SP J Non Crystalline Solids ID POLYMERS AB Dielectric measurements on tetramethyl-bisphenol-A polycarbonate (TMPC), polystyrene (PS), and 50 wt% TMPC/ PS blend were made in the frequency range of 0.1 mHz to 1 MHz at various temperatures. The alpha-relaxation process due to main-chain motions was observed for each polymer and the beta-relaxation processes due to local motions of TMPC were observed for TMPC and TMPC/PS blend. Plots of logarithm of the relaxation time for the beta process against the reciprocal of the absolute temperature were fit to Arrhenius functions for TMPC and the blend. However the relaxation strength and the shape parameter of the Cole-Cole equation had changes around the glass transition temperature, T-g. These changes in relaxation parameters around T-g was observed for the first time for the beta process. Based on these results we suggest that even the local chain motions are affected by the glass transition phenomena, although the beta process are not described by the Vogel-Fulcher-Tamman equation. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Tokai Univ, Dept Phys, Hiratsuka, Kanagawa 25912, Japan. USN, Res Lab, Washington, DC 20375 USA. RP Yagihara, S (reprint author), Tokai Univ, Dept Phys, Hiratsuka, Kanagawa 25912, Japan. EM yagihara@keyaki.cc.u-tokai.ac.jp NR 12 TC 17 Z9 17 U1 0 U2 2 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 AUG PY 1998 VL 235 BP 412 EP 415 DI 10.1016/S0022-3093(98)00511-0 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 118LC UT WOS:000075838800067 ER PT J AU Ngai, KL Rizos, AK Plazek, DJ AF Ngai, KL Rizos, AK Plazek, DJ TI Reduction of the glass temperature of thin freely standing polymer films caused by the decrease of the coupling parameter in the coupling model SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 3rd International Discussion Meeting on Relaxations in Complex Systems CY JUN 30-JUL 11, 1997 CL VIGO, SPAIN SP J Non Crystalline Solids ID PHOTON-CORRELATION SPECTROSCOPY; MOLECULAR-DYNAMICS SIMULATION; SEGMENTAL CHAIN DYNAMICS; BULK AMORPHOUS POLYMERS; TIME-SCALE SHIFTS; THERMORHEOLOGICAL COMPLEXITY; TRANSITION TEMPERATURE; CONSTRAINT DYNAMICS; NEUTRON-SCATTERING; CHEMICAL-STRUCTURE AB Dramatic reduction of the glass temperature, T-g, in freely standing polymer thin films has been found when the thickness of the films become approximately smaller than the average end-to-end distance of the unperturbed polymer chains. The observation of a large molecular weight dependence of the T-g reductions provides evidence for the importance of chain confinement effect on the glass temperature of thin polymer films. We propose that for freely standing polymer thin films of high molecular weights, there are: (a) induced orientations of the polymer chains when their average end-to-end distance becomes comparable to the film thickness and (b) decreases of the cooperative length scale for chain segments near the surfaces. As a consequence, the intermolecular constraints of local segmental motions for molecular units are reduced, particularly those located in the vicinity of the surfaces. The reduction of T-g is attributed to an attendant decrease of the coupling parameter in the coupling model. This explanation is consistent with a recent photon correlation spectroscopy (PCS) and quartz crystal microbalance (QCM) measurement of the dynamics of local segmental motions in polymer thin films. Calculation of the T-g of the thin film studied using the coupling model gives an order of magnitude estimate of the reduction of T-g, which is in agreement with experiment. (C) 1998 Elsevier Science B.V, All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Crete, Dept Chem, Heraklion 71409, Crete, Greece. Fdn Res & Technol Hellas, Heraklion 71409, Crete, Greece. Univ Pittsburgh, Dept Mat Sci & Engn, Pittsburgh, PA 15216 USA. RP Ngai, KL (reprint author), USN, Res Lab, 4555 Overlook Ave, Washington, DC 20375 USA. RI Rizos, Apostolos/F-6807-2011 NR 44 TC 65 Z9 67 U1 0 U2 4 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 AUG PY 1998 VL 235 BP 435 EP 443 DI 10.1016/S0022-3093(98)00656-5 PG 9 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 118LC UT WOS:000075838800071 ER PT J AU Santangelo, PG Roland, CM AF Santangelo, PG Roland, CM TI Effect of long-chain branching on the rheology of 1,4-polyisoprene SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 3rd International Discussion Meeting on Relaxations in Complex Systems CY JUN 30-JUL 11, 1997 CL VIGO, SPAIN SP J Non Crystalline Solids ID STAR POLYMERS; VISCOELASTIC PROPERTIES; TEMPERATURE-DEPENDENCE; MELT RHEOLOGY; POLYSTYRENES; REPTATION; POLYISOPRENES; RELAXATIONS; DIFFUSION; DYNAMICS AB The presence of long chain branches in 1,4-polyisoprene (PI) is shown to increase the sensitivity of temperature of the terminal relaxation. The excess activation energy associated with branching increases in proportion to the molecular weight of the branches. In these respects, PI behaves like other branched polymers, which means that the reptation-based interpretation of the temperature-dependence of branched polymers cannot be correct. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Div Chem, Res Lab, Washington, DC 20375 USA. RP USN, Div Chem, Res Lab, Code 6120, Washington, DC 20375 USA. EM Roland@nrl.navy.mil NR 36 TC 14 Z9 14 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 EI 1873-4812 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD AUG PY 1998 VL 235 BP 709 EP 716 DI 10.1016/S0022-3093(98)00623-1 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 118LC UT WOS:000075838800117 ER PT J AU Nicoll, BK Peters, RJ AF Nicoll, BK Peters, RJ TI Heat generation during ultrasonic instrumentation of dentin as affected by different irrigation methods SO JOURNAL OF PERIODONTOLOGY LA English DT Article DE scaling adverse effects; ultrasonics adverse effects; heat adverse effects AB HEAT IS PRODUCED BY MAGNETOSTRICTIVE ultrasonic scalers which may cause injury to pulpal and periodontal tissues. Water coolant flows around the instrument stack and is directed at the instrument tip to reduce the generation of heat. Sound surgical practice requires the use of a sterile coolant for ultrasonic scaling during surgery. Intermittent bulb irrigation is one way to deliver sterile coolant when using ultrasonic scalers not equipped with a dedicated sterile water reservoir. The purpose of this study was to compare the temperature rise in dentin during ultrasonic scaling using either ultrasonic handpiece irrigation or intermittent bulb irrigation. Twenty dentin/cementum root slabs were prepared for each thickness of 0.5, 1.5, and 2.5 mm. A 3.0 mm x 1.5 mm field was outlined on each slab to indicate the area of intended instrumentation, Each slab was mounted such that a thermocouple placed in contact with dentin opposite the area of instrumentation was shielded from irrigation. Twenty samples of each thickness were ultrasonically scaled during which dentin temperature was recorded every 5 seconds over a 30-second period. All 60 slabs were first treated with dental unit ultrasonic handpiece water irrigation, followed by no irrigation, and finally by bulb irrigation with sterile saline. Repeated measures analysis of variance indicated that there were differences among the three treatment groups for temperature change over the course of the study (P < 0.001). Dentin temperature increased with both decreasing slab thickness and with increasing duration of instrumentation. However, only scaling without irrigation produced a rise in dentin temperature from baseline to a level reported as deleterious to pulpal and periodontal tissues. Bulb syringe irrigation delivered as a continuous drip and ultrasonic unit water spray minimized heat generation to physiologically tolerable levels. Intermittent bulb irrigation appears to be a satisfactory alternative to use of ultrasonic scaler water spray for cooling during ultrasonic scaling at surgery. C1 USN, Sch Dent, Natl Naval Dent Ctr, Comprehens Dent Dept, Bethesda, MD 20889 USA. USN, Dent Res Inst, Detachment Bethesda, Bethesda, MD 20084 USA. RP Nicoll, BK (reprint author), USN, Sch Dent, Natl Naval Dent Ctr, Comprehens Dent Dept, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 19 TC 25 Z9 25 U1 0 U2 1 PU AMER ACAD PERIODONTOLOGY PI CHICAGO PA 737 NORTH MICHIGAN AVENUE, SUITE 800, CHICAGO, IL 60611-2690 USA SN 0022-3492 J9 J PERIODONTOL JI J. Periodont. PD AUG PY 1998 VL 69 IS 8 BP 884 EP 888 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 145PZ UT WOS:000077381600006 PM 9736371 ER PT J AU Sastri, SB Keller, TM AF Sastri, SB Keller, TM TI Phthalonitrile cure reaction with aromatic diamines SO JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY LA English DT Article DE phthalonitrile monomer; thermoset; curing agent; processability; thermal stability ID INTRINSICALLY CONDUCTIVE POLYMER; RESIN AB Phthalonitrile monomers can be polymerized thermally in the presence of small amounts of curing agents into thermosetting polymers. The thermosets exhibit outstanding thermo-oxidative stability, display good mechanical properties, and offer promise as matrices for composite applications. The phthalonitrile cure reaction is typically accomplished with an aromatic diamine, 1,3-bis(8-aminophenoxy) benzene (m-APB), added in the range of 1.5-2% by weight of the monomer in the melt phase. This article addresses the cure reaction with a sulfone-containing diamine, bis[4-(4-aminophenoxy)phenyl] sulfone (p -BAPS), which shows lower volatility as determined from thermogravimetric studies (TGA) compared to m-APB at the processing temperatures typically employed for phthalonitrile cures. Rheometric studies conducted to monitor the viscosity increase during a cure reaction suggest that the cure reaction with m-APB is faster compared to the reaction with B-BAPS. Even though differences are seen in the initial cure rates, the final cured products are similar in terms of the glass transition temperatures and thermal and oxidative stabilities. (C) 1998 John Wiley & Sons, Inc. C1 USN, Res Lab, Mat Chem Branch, Div Chem, Washington, DC 20375 USA. RP Sastri, SB (reprint author), USN, Res Lab, Mat Chem Branch, Div Chem, Code 6127, Washington, DC 20375 USA. NR 24 TC 83 Z9 89 U1 0 U2 21 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-624X J9 J POLYM SCI POL CHEM JI J. Polym. Sci. Pol. Chem. PD AUG PY 1998 VL 36 IS 11 BP 1885 EP 1890 DI 10.1002/(SICI)1099-0518(199808)36:11<1885::AID-POLA23>3.0.CO;2-9 PG 6 WC Polymer Science SC Polymer Science GA ZY284 UT WOS:000074604700023 ER PT J AU Houser, EJ Keller, TM AF Houser, EJ Keller, TM TI Hydrosilation routes to materials with high thermal and oxidative stabilities SO JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY LA English DT Article DE hydrosilation; polymer; siloxane ID DIACETYLENE COPOLYMERS; HYDROSILYLATION; POLYMERIZATION; POLYMERS C1 USN, Res Lab, Mat Chem Branch, Div Chem, Washington, DC 20375 USA. RP Houser, EJ (reprint author), USN, Res Lab, Mat Chem Branch, Div Chem, CODE 6120,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 21 TC 12 Z9 13 U1 1 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-624X J9 J POLYM SCI POL CHEM JI J. Polym. Sci. Pol. Chem. PD AUG PY 1998 VL 36 IS 11 BP 1969 EP 1972 DI 10.1002/(SICI)1099-0518(199808)36:11<1969::AID-POLA34>3.0.CO;2-A PG 4 WC Polymer Science SC Polymer Science GA ZY284 UT WOS:000074604700034 ER PT J AU Ngai, KL Schonhals, A AF Ngai, KL Schonhals, A TI Interpretation of the observed influence of mesophase structures on the beta-relaxation in side chain liquid crystal polymers SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE side chain liquid crystal polymers; beta-relaxation; rotation of mesogenic units; compensation law ID GLASS TRANSFORMATION TEMPERATURE; MOLECULAR-DYNAMICS SIMULATION; ELASTIC NEUTRON-SCATTERING; DISSOLVED POLYCARBONATES; DIELECTRIC-SPECTROSCOPY; CONDUCTIVITY SPECTRA; ALPHA-RELAXATION; SPIN RELAXATION; FORMING SYSTEMS; DEUTERON NMR AB A strong dependence of the rotational dynamics of the mesogenic units (beta- relaxation) on the order of the mesophase was found in sidechain liquid crystal polymers. The preexponential frequency factor, f (beta infinity)*, and the activation energy, E-alpha beta*, Of the p-relaxation rate both increase significantly (i.e., obeying a compensation law) with increasing order of the mesophase which is accompanied by a decrease of the mean lateral mesogenic distance. In this work, we show how these experimental results can be interpreted in a quantitative manner by using the general results of the coupling model for cooperative motions. (C) 1998 John Wiley & Sons. C1 USN, Res Lab, Dept Navy, Washington, DC 20375 USA. Bundesanstalt Mat Forsch & Pruefung, D-12205 Berlin, Germany. RP Ngai, KL (reprint author), USN, Res Lab, Dept Navy, Code 6807,4555 Overlook Ave SW, Washington, DC 20375 USA. RI Schoenhals, Andreas/E-4194-2010 NR 53 TC 13 Z9 13 U1 0 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD AUG PY 1998 VL 36 IS 11 BP 1927 EP 1934 DI 10.1002/(SICI)1099-0488(199808)36:11<1927::AID-POLB14>3.3.CO;2-A PG 8 WC Polymer Science SC Polymer Science GA ZY283 UT WOS:000074604600014 ER PT J AU Lind, CA Boris, JP Oran, ES Mitchell, WJ Wilcox, JL AF Lind, CA Boris, JP Oran, ES Mitchell, WJ Wilcox, JL TI The response of a partially confined detonation facility to blast loading SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 27-31, 1997 CL ORLANDO, FL SP Amer Soc Mech Engineers AB It is estimated that more than 500,000 tons of obsolete and unwanted conventional weapons exist in the United Stares. The disposal of these unexploded ordnances, in an environmentally sound and cost-effective way, is of paramount importance. Open-air burning and open-air detonation (OB/OD) are two of the most widely used methods to dispose of these unwanted energetic materials. This paper describes our efforts to improve OB/OD operations through the design and testing of a new, large-scale, partially confined facility that minimizes the adverse affects of far-field noise and maximizes the afterburn of explosive by-products. Several designs were evaluated by a series of axisymmetric, time-dependent numerical simulations using FAST3D, a flux-corrected transport-based code optimized for parallel processing. The simulations are used to test various facility geometries and placements and sizes of charges to determine combinations that result in acceptable environmental impact. Comparisons of the pressure and structural analyses far 50 and 100 lb of spherically shaped RDX charges show that the 50-lb spherically shaped charge placed at a height of approximately 2.0 m resulted in an efficient detonation and maintained the structural integrity of the detonation facility. C1 USN, Computat Phys & Fluid Dynam Lab, Washington, DC 20372 USA. US EPA, Off Res & Dev, Res Triangle Pk, NC 27711 USA. USA, W Desert Test Ctr, Dugway, UT 84022 USA. RP USN, Computat Phys & Fluid Dynam Lab, Code 6440,B-97,4555 Overlook Ave SW, Washington, DC 20372 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU ASME PI NEW YORK PA TWO PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-9930 EI 1528-8978 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD AUG PY 1998 VL 120 IS 3 BP 306 EP 312 DI 10.1115/1.2842062 PG 7 WC Engineering, Mechanical SC Engineering GA 112TX UT WOS:000075511200015 ER PT J AU Lind, CA Boris, JP Oran, ES Mitchell, WJ Wilcox, JL AF Lind, CA Boris, JP Oran, ES Mitchell, WJ Wilcox, JL TI The effect of charge shape on partially confined detonations SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 27-31, 1997 CL ORLANDO, FL SP Amer Soc Mech Engineers AB More than 500,000 tons of obsolete and unwanted conventional weapons exist in the United States. The disposal of these unexploded ordnances, in an environmentally sound and cost-effective way, is of paramount importance. Different types of incinerators and detonation chambers have been proposed to eliminate these unwanted energetic materials. However, questions about the design of such facilities and the environmental consequences of their use must be answered. This paper describes numerical simulations of a large-scale partially confined detonation facility. Detonation facility designs were evaluated by a sei-ies of axisymmetric, time-dependent simulations using FAST3D, a numerical model based on flux-connected transport coupled to the virtual cell embedding algorithm for simulating complex geometries. The simulations assisted in determining the shape and size of the detonation charge mass that maintained the structural integrity of the facility. Comparisons of the pressure and structural analyses for spherically and cylindrically shaped RDX charges in a fired volume show that the 50-lb spherically shaped charge resulted in an efficient detonation and maintained the structural integrity of the detonation facility. C1 USN, Computat Phys & Fluid Dynam Lab, Washington, DC 20372 USA. US EPA, Off Res & Dev, Res Triangle Pk, NC 27711 USA. USA, W Desert Test Ctr, Dugway, UT 84022 USA. RP USN, Computat Phys & Fluid Dynam Lab, Code 6440,B-97,4555 Overlook Ave SW, Washington, DC 20372 USA. NR 10 TC 0 Z9 0 U1 1 U2 1 PU ASME PI NEW YORK PA TWO PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-9930 EI 1528-8978 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD AUG PY 1998 VL 120 IS 3 BP 313 EP 318 DI 10.1115/1.2842063 PG 6 WC Engineering, Mechanical SC Engineering GA 112TX UT WOS:000075511200016 ER PT J AU Luqi Chang, CK Zhu, H AF Luqi Chang, CK Zhu, H TI Specifications in software prototyping SO JOURNAL OF SYSTEMS AND SOFTWARE LA English DT Article ID LANGUAGE AB We explore the use of software specifications for software prototyping. This paper describes a process model for software prototyping, and shows how specifications can be used to support such a process via a cellular mobile phone switch example. (C) 1998 Elsevier Science Inc. All rights reserved. C1 Univ Illinois, Dept EECS MC154, Chicago, IL 60607 USA. USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. Nanjing Univ, Inst Comp Software, Nanjing 210093, Peoples R China. RP Univ Illinois, Dept EECS MC154, Chicago, IL 60607 USA. EM ckchang@eecs.uic.edu RI Zhu, Hong/B-3231-2011 OI Zhu, Hong/0000-0001-9393-5005 NR 24 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0164-1212 EI 1873-1228 J9 J SYST SOFTWARE JI J. Syst. Softw. PD AUG PY 1998 VL 42 IS 2 BP 125 EP 140 PG 16 WC Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA 109AY UT WOS:000075300100004 ER PT J AU Berzins, V AF Berzins, V TI Recombining changes to software specifications SO JOURNAL OF SYSTEMS AND SOFTWARE LA English DT Article DE software evolution; change merging; specifications; logic ID PROGRAMS AB This paper proposes a model of software changes for supporting the evolution of software prototypes. We decompose software evolution steps into primitive substeps that correspond to monotonic specification changes. This structure is used to rearrange chronological derivation sequences into idealized conceptual derivation structures containing only meaning-extending changes, and to automatically combine different changes to a specification. A set of examples illustrates the ideas. (C) 1998 Elsevier Science Inc. All rights reserved. C1 USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. RP Berzins, V (reprint author), USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. NR 28 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0164-1212 J9 J SYST SOFTWARE JI J. Syst. Softw. PD AUG PY 1998 VL 42 IS 2 BP 165 EP 174 DI 10.1016/S0164-1212(98)10007-9 PG 10 WC Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA 109AY UT WOS:000075300100007 ER PT J AU Lim, R AF Lim, R TI Acoustic scattering by a partially buried three-dimensional elastic obstacle SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID 2 HALF-SPACES; WAVE SCATTERING; MULTIPLE-SCATTERING; T-MATRIX; FLUID; PROPAGATION; REFLECTION; MEDIA AB A transition-matrix solution for the spectral scattering response of an elastic obstacle that penetrates a plane-stratified fluid host is formulated. The field scattered from the segment in each layer is expanded in a global outgoing basis centered on that segment and these segment fields are superposed at the field point. A manageable structure for the transition matrix is maintained by using the boundary conditions to couple these segment fields to the interior held of the obstacle via exterior surface field expansions centered on the primary origin of the obstacle. Two formulations are presented and compared in which the surface fields are expanded in either the standard set of regular spherical eigenfunctions of the Helmholtz equation or the spherical harmonics. Numerical tests for an axisymmetric spheroid indicate both formulations are viable but exhibit different convergence and stability characteristics. However, in both cases, convergence is better for flattened shapes (oblate) than elongated shapes (prolate). Examples are presented to illustrate environmental effects on the backscatter by a bubble and elastic spheres and spheroids that penetrate a water/ sediment interface. [S0001-4966(98)02207-3] C1 USN, Ctr Surface Warfare, Coastal Syst Stn, Dahlgren Div, Panama City, FL 32407 USA. RP Lim, R (reprint author), USN, Ctr Surface Warfare, Coastal Syst Stn, Dahlgren Div, Code R22,6703 W Highway 98, Panama City, FL 32407 USA. NR 33 TC 21 Z9 21 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 AUG PY 1998 VL 104 IS 2 BP 769 EP 782 DI 10.1121/1.423352 PN 1 PG 14 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 108FF UT WOS:000075254800020 ER PT J AU Lingevitch, JF Collins, MD AF Lingevitch, JF Collins, MD TI Wave propagation in range-dependent poro-acoustic waveguides SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID CONSERVING PARABOLIC EQUATION; ELASTIC MEDIA; OCEAN; REFLECTION; INTERFACE; DEPTH AB The parabolic equation method is extended to handle range-dependent pore-acoustic waveguides. A pore-acoustic medium is the limiting case of a pore-elastic medium in which the shear wave speed vanishes. Recent experiments indicate that this is a relevant limit [Chotiros, "Biot model of sound propagation in water-saturated sand," J. Acoust. Soc. Am. 97, 199-214 (1995)]. Energy-conserving and single-scattering techniques are developed for handling vertical interfaces. The single-scattering solution is extended to problems involving fluid layers above pore-acoustic sediments. Improved rational function approximations are developed by rotating the branch cut [Milinazzo et al, "Rational square-root approximations for parabolic equation algorithms," J. Acoust. Sec. Am. 101, 760-766 (1997)]. [S0001-4966(98)05507-6] C1 USN, Res Lab, Washington, DC 20375 USA. RP Lingevitch, JF (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 22 TC 20 Z9 20 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 AUG PY 1998 VL 104 IS 2 BP 783 EP 790 DI 10.1121/1.423239 PN 1 PG 8 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 108FF UT WOS:000075254800021 ER PT J AU Cuschieri, JM Feit, D AF Cuschieri, JM Feit, D TI Full numerical solution for the far-field and near-field scattering from a fluid-loaded elastic plate with distributed mass or stiffness inhomogeneity SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The scattering of a plane acoustic wave by a fluid-loaded thin elastic plate of infinite extent with a distributed mass or stiffness inhomogeneity is investigated. This paper is a follow up to previous work done by the same authors on the scattering from a fluid-loaded plate with a distributed mass inhomogeneity. In this paper both stiffness and mass distributed inhomogeneities are considered and a complete description of the full numerical solution is presented. Furthermore, both near-field and far-field scattering results are presented in this paper. The presence of the, distributed inhomogeneity modifies the wave number transform of the equation of motion of the fluid-loaded plate to a Fredholm integral equation. This integral equation has singularities at the roots of the dispersion equation. To obtain a complete numerical solution of the Fredholm integral equation, a singularity subtraction technique is used, which is similar in essence to the hybrid analytic/numerical approach for the solution of the scattering from a fluid-loaded elastic plate [J. Acoust. Sec. Am. 95, 1998-2005 (1994)]. The solution to the resulting Fredholm integral equation of the second kind is obtained using the Nystrom approximation. The results for the far-field scattering are for an oblique angle of incidence and for monostatic scattering. The results show that mass distributed inhomogeneities are stronger scatterers than distributed stiffness inhomogeneities for frequencies below the critical frequency of the plate. Above the critical frequency, both types of inhomogeneities have similar scattering strengths. Also included are results for different types of inhomogeneity distributions. This work was sponsored by ONR. (C) 1998 Acoustical Society of America. [S0001-4966(98)01708-1]. C1 Florida Atlantic Univ, Dept Ocean Engn, Ctr Acoust & Vibrat, Boca Raton, FL 33431 USA. David Taylor Res Ctr, NSWC, Carderock Div, Bethesda, MD 20817 USA. RP Cuschieri, JM (reprint author), Florida Atlantic Univ, Dept Ocean Engn, Ctr Acoust & Vibrat, Boca Raton, FL 33431 USA. NR 7 TC 8 Z9 8 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 AUG PY 1998 VL 104 IS 2 BP 915 EP 925 DI 10.1121/1.423337 PN 1 PG 11 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 108FF UT WOS:000075254800036 ER PT J AU Lee, HS Yang, XQ Xiang, CL McBreen, J Choi, LS AF Lee, HS Yang, XQ Xiang, CL McBreen, J Choi, LS TI The synthesis of a new family of boron-based anion receptors and the study of their effect on ion pair dissociation and conductivity of lithium salts in nonaqueous solutions SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID COMPLEXES AB A new family of anion receptors based on boron compounds has been synthesized. These compounds can be used as anion receptors in lithium battery electrolytes. This family includes various borane and berate compounds with different fluorinated aryl and fluorinated alkyl groups. When these anion receptors are used as additives in 1,2-dimethoxyethane (DME) solutions containing various lithium salts, the ionic conductivities of these solutions are greatly increased. The electrolytes tested in this study were DME solutions containing the following lithium salts: LiF, LiCl, LiBr, LiI, CF3COOLi, and C2F5COOLi. Without the additive, the solubility of LiF in DME land all other nonaqueous solvents) is very low With some of these boron compounds as additives, LiF solutions in DME with concentration as high as 1 M were obtained. The solubilities of the other salts were also increased by these additives. Near edge X-ray absorption fine structure (NEXAFS) spectroscopy studies show that Cl- and I- anions are complexed with these compounds in DME solutions containing LiCl or LiI salts. The degree of complexation is also closely related to the structures of the fluorinated aryl and alkyl groups, which act as electron-withdrawing groups. The NEXAFS results are in good agreement with ionic conductivity studies. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. USN, Res Lab, Washington, DC 20375 USA. RP Lee, HS (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 8 TC 108 Z9 115 U1 3 U2 35 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 1998 VL 145 IS 8 BP 2813 EP 2818 DI 10.1149/1.1838719 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 104BE UT WOS:000074991700031 ER PT J AU Driscoll, TJ Kallen, AJ AF Driscoll, TJ Kallen, AJ TI Reading the E-test - Response SO LABORATORY MEDICINE LA English DT Letter C1 USN, Med Ctr, Div Infect Dis, San Diego, CA 92152 USA. RP Driscoll, TJ (reprint author), USN, Med Ctr, Div Infect Dis, San Diego, CA 92152 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CLIN PATHOLOGISTS PI CHICAGO PA 2100 W HARRISON ST, CHICAGO, IL 60612 USA SN 0007-5027 J9 LAB MED JI Lab. Med. PD AUG PY 1998 VL 29 IS 8 BP 457 EP 457 PG 1 WC Medical Laboratory Technology SC Medical Laboratory Technology GA 106BJ UT WOS:000075109600003 ER PT J AU Spanos, G Hyland, RW AF Spanos, G Hyland, RW TI Symposium on kinetically determined particle shapes and the dynamics of solid : solid interfaces - Foreword SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Editorial Material C1 USN, Res Lab, Washington, DC 20375 USA. ALCOA, Pittsburgh, PA 15219 USA. RP Spanos, G (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD AUG PY 1998 VL 29 IS 8 BP 2019 EP 2019 PG 1 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 111EP UT WOS:000075424600001 ER PT J AU Fonda, RW Mangan, MA Shiflet, GJ AF Fonda, RW Mangan, MA Shiflet, GJ TI The effect of undercooling on the cellular precipitation reaction in Cu-3 Pct Ti SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Kinetically Determined Particle Shapes and the Dynamics of Solid - Solid Interfaces CY OCT, 1996 CL CINCINNATI, OHIO SP TMS, ASM ID ALLOYS AB The effect of undercooling on the morphology of the cellular precipitation reaction in Cu-3 Pet Ti is examined by scanning electron microscopy (SEM, transmission electron microscopy (TEM), and serial sectioning experiments. The reaction front formed at small undercooling, which exhibits strong faceting of the precipitate growth interfaces, gradually changes with increasing undercooling to a smoothly curved reaction front with concave precipitate growth interfaces and convex grain boundary segments. This concealment of the faceted reaction front appears to be due to the rapid accumulation of growth ledges with increasing undercooling. This study also indicates that the cellular precipitation reaction, at small undercooling, is initiated by Widmanstatten precipitation. At larger undercoolings, a second mechanism is responsible for cellular genesis. Finally, contrary to accepted models of colony development, serial sectioning experiments show that nucleation of additional lamellae may occur at the faces of existing lamellae, from where they extend laterally to achieve the characteristic interlamellar spacing for that temperature. C1 Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22903 USA. RP Fonda, RW (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 23 TC 3 Z9 3 U1 1 U2 5 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD AUG PY 1998 VL 29 IS 8 BP 2101 EP 2110 DI 10.1007/s11661-998-0035-z PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 111EP UT WOS:000075424600009 ER PT J AU Dansak, DA AF Dansak, DA TI Childhood abuse and parental disorders reported by Navy outpatient mental health patients SO MILITARY MEDICINE LA English DT Article ID SEXUAL ABUSE; PHYSICAL ABUSE; PSYCHIATRIC OUTPATIENTS; ADULT LIFE; HISTORIES; IMPACT; CONSEQUENCES; INPATIENTS; COMMUNITY; STRESS AB Objective: To ascertain the number of Navy outpatient mental health patients reporting a history of childhood abuse. To explore the relationships among abuse history, parental/step-parental substance abuse, mental illness, and divorce. Method: Review of 134 clinical data forms completed by patients when first seen. Results: Twenty-six percent reported at least one type of childhood abuse (physical, sexual, verbal, emotional). Proportionally more females reported any one type of abuse. Assailants were predominantly males, typically fathers or stepfathers. Verbal abuse significantly affected childhood happiness. Parental substance abuse, mental illness, or divorce before age 19 reduced childhood happiness, and abuse further reduced it. Conclusion: Childhood abuse is commonly reported by Navy mental health patients and may affect their adjustment to military life. C1 USN Hosp, Dept Mental Hlth, Pensacola, FL 32512 USA. RP Dansak, DA (reprint author), USN Hosp, Dept Mental Hlth, 6000 W Highway 98, Pensacola, FL 32512 USA. NR 21 TC 5 Z9 6 U1 2 U2 2 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 AUG PY 1998 VL 163 IS 8 BP 510 EP 514 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA 110MT UT WOS:000075385500003 PM 9715612 ER PT J AU Hudson, SJ Todd, JS AF Hudson, SJ Todd, JS TI Rapid decompression in the EA-6B SO MILITARY MEDICINE LA English DT Article AB A Grumman EA-6B aircraft experienced a rapid pressurization failure at 27,000 feet. All four crew members had removed their oxygen masks and were breathing cabin air pressurized to 8,000 feet before the incident. Although none of the crew members developed signs or symptoms of decompression sickness, the potential for adversity was realized by all. Altitude decompression sickness (DCS) and pulmonary overinflation syndrome (POIS) represent potentially fatal complications of rapid decompression or uncontrolled ascent in aircraft. The signs and symptoms of DCS range from mild joint pain to eventual cardiopulmonary collapse and death. The symptoms of POIS are usually more abrupt and lethal. The medical management of DCS and POIS includes (1) maintenance of airway and cardiopulmonary resuscitation if necessary; (2) administration of 100% oxygen; (3) descent as per Naval Aviation Training and Operating Procedures Standardization guidelines; (4) horizontal body position; (5) maintenance of fluid intake; and (6) early medical evaluation by a flight surgeon or other physician qualified in the management of DCS. Symptoms of DCS may appear up to 24 hours after decompression, and continued monitoring or grounding of exposed individuals during this time is essential. Many controllable factors may predispose to DCS/POIS, and preventive measures should be taken to ensure maximum reduction of risk. C1 USN Hosp, Dept Aviat Med, Oak Harbor, WA 98278 USA. RP Hudson, SJ (reprint author), USN Hosp, Dept Aviat Med, Oak Harbor, WA 98278 USA. NR 4 TC 0 Z9 0 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 AUG PY 1998 VL 163 IS 8 BP 572 EP 574 PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA 110MT UT WOS:000075385500015 PM 9715624 ER PT J AU Hill, JM AF Hill, JM TI Pride and prodigies: Studies in the monsters of the 'Beowulf' manuscripts SO MODERN PHILOLOGY LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Hill, JM (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0026-8232 J9 MOD PHILOLOGY JI Mod. Philol. PD AUG PY 1998 VL 96 IS 1 BP 58 EP 61 DI 10.1086/492717 PG 4 WC Language & Linguistics; Literature SC Linguistics; Literature GA 116MV UT WOS:000075729900006 ER PT J AU Hill, JM AF Hill, JM TI Interactions of thought and language in Old English poetry SO MODERN PHILOLOGY LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Hill, JM (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0026-8232 J9 MOD PHILOLOGY JI Mod. Philol. PD AUG PY 1998 VL 96 IS 1 BP 61 EP 65 DI 10.1086/492718 PG 5 WC Language & Linguistics; Literature SC Linguistics; Literature GA 116MV UT WOS:000075729900007 ER PT J AU Rosen, M Efros, A AF Rosen, M Efros, A TI Effective mass approximation revisited SO MRS BULLETIN LA English DT Letter ID CDSE QUANTUM DOTS; ASSIGNMENT; SPECTRUM C1 USN, Res Lab, Washington, DC 20375 USA. RP Rosen, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 10 TC 4 Z9 4 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD AUG PY 1998 VL 23 IS 8 BP 6 EP 6 PG 1 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 111EK UT WOS:000075424200002 ER PT J AU Spatz, M Kawai, N Bembry, J Lenz, F McCarron, RM AF Spatz, M Kawai, N Bembry, J Lenz, F McCarron, RM TI Human brain capillary endothelium: Modulation of K+ efflux and K+, Ca2+ uptake by endothelin SO NEUROCHEMICAL RESEARCH LA English DT Article DE human brain capillary endothelium; endothelin-1; K+ efflux; K+ uptake; Ca2+ uptake ID IMMUNOREACTIVE ENDOTHELIN-1; SIGNAL-TRANSDUCTION; ET(A) RECEPTORS; CELLS; BIOCHEMISTRY; ISCHEMIA; BARRIER; SODIUM AB This report describes K+ efflux, K+ and Ca2+ uptake responses to endothelins (ET-1 and ET-3) in cultured endothelium derived from capillaries of human brain (HBEC). ET-1 dose dependently increased K+ efflux, K+ and Ca2+ uptake in these cells. ET-1 stimulated K+ efflux occurred prior to that of K+ uptake. ET-3 was ineffective. The main contributor to the ET-1 induced K+ uptake was ouabain but not bumetanide-sensitive (Na+-K+-ATPase and Na+-K+-Cl- cotransport activity, respectively). All tested paradigms of ET-1 effects in HBEC were inhibited by selective antagonist of ETA but not ETB receptors and inhibitors of phospholipase C and receptor-operated Ca2+ channels. Activation of protein kinase C (PKC) decreased whereas inhibition of PKC increased the ET-1 stimulated K+ efflux, K+ and Ca2+ uptake in HBEC. The results indicate that ET-1 affects the HBEC ionic transport systems through activation of ETA receptors linked to PLC and modulated by intracellular Ca2+ mobilization and PKC. C1 NINDS, Stroke Branch, NIH, Bethesda, MD 20892 USA. Johns Hopkins Univ Hosp, Baltimore, MD 21205 USA. USN, Resuscitat Med Program, Med Res Inst, Bethesda, MD 20889 USA. RP Spatz, M (reprint author), NINDS, Stroke Branch, NIH, 36 Convent Dr,MSC 4128, Bethesda, MD 20892 USA. NR 25 TC 4 Z9 4 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0364-3190 J9 NEUROCHEM RES JI Neurochem. Res. PD AUG PY 1998 VL 23 IS 8 BP 1125 EP 1132 DI 10.1023/A:1020772422266 PG 8 WC Biochemistry & Molecular Biology; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA 105TE UT WOS:000075089000014 PM 9704603 ER PT J AU Navar, LG Zou, LX Von Thun, A Wang, CT Imig, JD Mitchell, KD AF Navar, LG Zou, LX Von Thun, A Wang, CT Imig, JD Mitchell, KD TI Unraveling the mystery of Goldblatt hypertension SO NEWS IN PHYSIOLOGICAL SCIENCES LA English DT Article ID II-INFUSED RATS; ANGIOTENSIN-II; BLOOD-PRESSURE; 2-KIDNEY AB In hypertension caused by unilateral renal artery stenosis, the nonstenotic kidney becomes renin depleted but fails to prevent hypertension. The nonstenotic kidney mysteriously develops elevated infrarenal angiotensin II (ANG II) content. Rats chronically infused with ANG II exhibit a similar hypertensive process. The augmentation of intrarenal ANG II is due to receptor-mediated internalization and continued ANG II formation, which provide a hypertensinogenic stimulus. C1 Tulane Univ, Sch Med, Dept Physiol, New Orleans, LA 70112 USA. USN, Med Ctr, Dept Internal Med, San Diego, CA USA. Gen Hosp, Dept Internal Med, Nephrol Sect, Taipei, Taiwan. RP Navar, LG (reprint author), Tulane Univ, Sch Med, Dept Physiol, New Orleans, LA 70112 USA. OI Imig, John/0000-0002-9668-2899 NR 15 TC 75 Z9 79 U1 0 U2 0 PU NEWS IN PHYSIOLOGICAL SCIENCES PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0886-1714 J9 NEWS PHYSIOL SCI JI News Physiol. Sci. PD AUG PY 1998 VL 13 BP 170 EP 176 PG 7 WC Physiology SC Physiology GA 113AC UT WOS:000075526300003 ER PT J AU Kang, JU Frankel, MY Esman, RD AF Kang, JU Frankel, MY Esman, RD TI Demonstration of microwave frequency shifting by use of a highly chirped mode-locked fiber laser SO OPTICS LETTERS LA English DT Article AB We report an experimental demonstration of a photonic microwave shifter using a highly chirped mode-locked fiber laser. The system is based on dispersive compression or expansion of highly chirped optical pulses that are amplitude modulated by the microwave signal. Using this technique, we demonstrated frequency shifting of a microwave signal from 10 GHz down to 5 GHz and up to 25 GHz. (C) 1998 Optical Society of America. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kang, JU (reprint author), USN, Res Lab, Code 5670,4555 Overlook Ave SW, Washington, DC 20375 USA. RI Kang, Jin/A-3228-2010 NR 6 TC 21 Z9 21 U1 0 U2 0 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 AUG 1 PY 1998 VL 23 IS 15 BP 1188 EP 1190 DI 10.1364/OL.23.001188 PG 3 WC Optics SC Optics GA 104QC UT WOS:000075024400014 PM 18087469 ER PT J AU Wheeler, DS Shope, TR AF Wheeler, DS Shope, TR TI Questions about toy car head injury - In reply SO PEDIATRICS LA English DT Letter C1 USN Hosp, FPO, AP 96538 USA. Johns Hopkins Childrens Ctr, Div Gen Pediat, Baltimore, MD 21287 USA. RP Wheeler, DS (reprint author), USN Hosp, PSC 490 Box 221, FPO, AP 96538 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER ACAD PEDIATRICS PI ELK GROVE VILLAGE PA 141 NORTH-WEST POINT BLVD,, ELK GROVE VILLAGE, IL 60007-1098 USA SN 0031-4005 J9 PEDIATRICS JI Pediatrics PD AUG PY 1998 VL 102 IS 2 BP 438 EP 438 PG 1 WC Pediatrics SC Pediatrics GA 106JH UT WOS:000075125800038 ER PT J AU Rhodenizer, L Bowers, CA AF Rhodenizer, L Bowers, CA TI Team practice schedules: What do we know? SO PERCEPTUAL AND MOTOR SKILLS LA English DT Article AB Given the prevalence of teams in many work environments, it is important to determine the practice schedules that optimize their learning. Thus, the effect of practice schedule on team learning was investigated. Teams practiced under either a massed or distributed practice schedule and were tested under a short-term or longer-term retention interval. These results support the distribution of practice effect for team learning; however, the results suggest that the known benefits for longer-term retention that distributed practice has on individual learning may not apply to learning by 2-person teams under the present conditions. C1 Univ Cent Florida, Dept Psychol, Team Performance Lab, Orlando, FL 32816 USA. USN, Air Warfare Ctr Training Syst Div, Washington, DC USA. RP Rhodenizer, L (reprint author), Univ Cent Florida, Dept Psychol, Team Performance Lab, 4000 Cent Florida Blvd, Orlando, FL 32816 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU PERCEPTUAL MOTOR SKILLS PI MISSOULA PA PO BOX 9229, MISSOULA, MT 59807 USA SN 0031-5125 J9 PERCEPT MOTOR SKILL JI Percept. Mot. Skills PD AUG PY 1998 VL 87 IS 1 BP 31 EP 34 PG 4 WC Psychology, Experimental SC Psychology GA 117ZN UT WOS:000075812900004 ER PT J AU Aglitskiy, Y Serpa, FG Meyer, ES Gillaspy, JD Brown, CM Faenov, AY Pikuz, TA AF Aglitskiy, Y Serpa, FG Meyer, ES Gillaspy, JD Brown, CM Faenov, AY Pikuz, TA TI The use of a spherically curved crystal spectrometer for X-ray measurements on electron beam ion trap SO PHYSICA SCRIPTA LA English DT Article ID SPECTROSCOPIC INVESTIGATIONS; MICA CRYSTALS; PLASMA; PERFORMANCE; WAVELENGTHS; REFLECTION; ALPHA; LINE AB Spherically curved crystal spectrometers are demonstrated for use on an Electron Beam Ion Trap (EBIT) for the first time. Such spectrometers are characterized by high light collection efficiency and relative insensitivity to source position, simultaneously giving them an advantage that no X-ray spectrometer previously used on an EBIT has had. One of the spectrometer crystals tested is composed of mica, giving it the additional advantage that it can be used with reasonable efficiency up to very high order, allowing spectra to span a broad wavelength range from 0.5 Angstroms to 20 Angstroms. Spectra from Ne-like barium and He-like argon are presented. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. USN, Res Lab, Washington, DC 20375 USA. VNIIFTRI, Multicharged Ions Spectra Data Ctr, Mendeleevo 141570, Moscow Region, Russia. RP Aglitskiy, Y (reprint author), Sci Applicat Int Corp, Mclean, VA 22102 USA. NR 32 TC 10 Z9 12 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PD AUG PY 1998 VL 58 IS 2 BP 178 EP 181 DI 10.1088/0031-8949/58/2/012 PG 4 WC Physics, Multidisciplinary SC Physics GA 110AG UT WOS:000075356700012 ER PT J AU Peiris, SM Heinz, DL AF Peiris, SM Heinz, DL TI Compression of seven vacancy-ordered phases of ScxS to 50 GPa SO PHYSICAL REVIEW B LA English DT Article ID TRANSITION-METAL CHALCOGENIDES; NONSTOICHIOMETRY; PRESSURE; ORIGIN; SCS AB The ScxS system. (0.80.01. The coarsening rate of the average particle can be calculated directly from dynamic simulations and indirectly from snapshot simulations by a perturbation relation. A different type of snapshot-ensemble averaging is suggested on the basis of the functional nature of the individual particle monopole source or sink strengths. Dynamic and snapshot simulations with dipoles were carried out up to a volume fraction of 0.25, and departure from Debye screening behavior was observed. The inclusion of dipole terms affects the deviations noticeably only above a volume fraction of 0.1. C1 Rensselaer Polytech Inst, Dept Chem Engn, Troy, NY 12180 USA. Royal Inst Technol, Dept Solid Mech, SE-10044 Stockholm, Sweden. USN, Res Lab, Mat Phys Branch, Washington, DC 20375 USA. RP Mandyam, H (reprint author), Rensselaer Polytech Inst, Dept Chem Engn, Troy, NY 12180 USA. OI Helsing, Johan/0000-0003-1434-9222; Glicksman, Martin/0000-0002-2675-2759 NR 36 TC 18 Z9 19 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 AUG PY 1998 VL 58 IS 2 BP 2119 EP 2130 DI 10.1103/PhysRevE.58.2119 PN B PG 12 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 110LW UT WOS:000075381500020 ER PT J AU McDevitt, ER AF McDevitt, ER TI On-site treatment of PIP joint dislocations SO PHYSICIAN AND SPORTSMEDICINE LA English DT Article C1 USN Acad, Annapolis, MD 21402 USA. Amer Orthopaed Soc Sports Med, Council Delegates, Rosemont, IL USA. MinnHlth SportsCare, White Bear Lake, MN USA. RP McDevitt, ER (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU MCGRAW HILL HEALTHCARE PUBLICATIONS PI MINNEAPOLIS PA 4530 WEST 77TH ST, MINNEAPOLIS, MN 55435-5000 USA SN 0091-3847 J9 PHYSICIAN SPORTSMED JI Physician Sportsmed. PD AUG PY 1998 VL 26 IS 8 BP 85 EP 86 PG 2 WC Primary Health Care; Orthopedics; Sport Sciences SC General & Internal Medicine; Orthopedics; Sport Sciences GA 106HW UT WOS:000075124700018 PM 20086847 ER PT J AU Lin, J Cassell, J Ritchie, GD Rossi, J Nordholm, AF AF Lin, J Cassell, J Ritchie, GD Rossi, J Nordholm, AF TI Repeated exposure to trimethylolpropane phosphate induces central nervous system sensitization and facilitates electrical kindling SO PHYSIOLOGY & BEHAVIOR LA English DT Article DE TMPP; PTZ; FG-7142; sensitization; kindling electrical and chemical; limbic system amygdala ID STRUCTURE-TOXICITY RELATIONSHIPS; BICYCLIC PHOSPHORUS ESTERS; GABA ANTAGONISTS; PENTYLENETETRAZOL; RATS; THRESHOLD; SEIZURES; SUSCEPTIBILITY; AMYGDALA AB Trimethylolpropane phosphate (TMPP), pentylenetetrazol (PTZ) and N-methyl-beta-carboline-3-carboxamide (FG-7142) were evaluated and compared for facilitation of electrical kindling in freely moving rats. Stimulating/recording electrodes were implanted in the left amygdala (LAD), right amygdala (RAD) and left bed nucleus (LBN) of the stria terminalis. TMPP (0.275 mg/kg), PTZ (20 mg/kg), FG-7142 (7.5 mg/kg) or vehicle was administered intraperitoneally (i.p.) to separate groups of rats 3 times/week for 10 weeks. Stimulation of the LAD (0.1 Hz, 0.1-ms duration, 280-1500 mu A, 20 pulses) 24 h following the drug administration evoked epileptiform after-discharges (ADs) in the LBN and RAD of 12.5% and 17% of rats after the seventh dose of TMPP and PTZ, respectively, and in 20% of rats from the LBN and RAD after the ninth and nineteenth dose of FG-7142, respectively. The same stimulation also induced myoclonic jerks after nine doses of TMPP or PTZ, or after thirteen doses of FG-7142 in 25%, 30% aid 20% of animals tested, respectively. Chemically kindled clonic seizures were observed in 100% of TMPP or FG-7142 and 50% of PTZ treated rats by the thirtieth dosing. Control animals exhibited neither behavioral nor electrographic seizures to vehicle injection or to the LAD stimulation. Kindling stimulation applied to the LAD (60 Hz, 2-s train duration, 20-1500 mu A, 0.1-ms pulse duration) 4 weeks following the completion of drug treatments evoked epileptic after-discharges from the LAD, LBN and RAD in all treated groups, with generally decreased threshold and latency to onset of after-discharges, compared to vehicle controls. The present study suggests that repeated exposure of rats to sub-convulsive doses of TMPP, PTZ and FG-7142 induces long-term central nervous system sensitization that may be related to both chemical kindling and the facilitation of electrical kindling. (C) 1998 Elsevier Science Inc. C1 ManTech Environm Technol Inc, Dayton, OH 45437 USA. USN, Med Res Inst, Detachment Toxicol, NMRI,TD, Wright Patterson AFB, OH 45433 USA. RP Lin, J (reprint author), ManTech Environm Technol Inc, POB 31009, Dayton, OH 45437 USA. NR 46 TC 8 Z9 9 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0031-9384 J9 PHYSIOL BEHAV JI Physiol. Behav. PD AUG PY 1998 VL 65 IS 1 BP 51 EP 58 DI 10.1016/S0031-9384(98)00131-0 PG 8 WC Psychology, Biological; Behavioral Sciences SC Psychology; Behavioral Sciences GA 131RB UT WOS:000076588100007 PM 9811364 ER PT J AU Zukowski, ML Ash, K Spencer, D Malanoski, M Moore, G AF Zukowski, ML Ash, K Spencer, D Malanoski, M Moore, G TI Endoscopic intracorporal abdominoplasty: A review of 85 cases SO PLASTIC AND RECONSTRUCTIVE SURGERY LA English DT Article; Proceedings Paper CT 14th Annual Lipoplasty-Society-of-North-America CY NOV, 1996 CL DALLAS, TEXAS SP Lipoplasty Soc N Amer ID COMPLICATIONS; LIPOPLASTY; LIPECTOMY AB The specialty of plastic surgery has witnessed an explosion of novel procedures with the advent of endoscopy. Surgeons are making more aggressive attempts to reduce the length of scars and subsequent morbidity associated with traditional "open" procedures. Our purpose is to present a new technique of endoscopic abdominoplasty that has largely replaced traditional "full open" techniques at our institution. Since 1985, 85 patients have undergone a procedure that we call the endoscopic intracorporal abdominoplasty. This technique combines traditional abdominal wall liposuction with endoscopic intracorporal plication of the rectus fascia by using a series of horizontal mattress sutures. The procedure is performed using three I-cm incisions and a series of midline and lateral skin nicks. These 85 patients were compared with 25 patients who underwent traditional open abdominoplasty with anterior plication of the rectus fascia. average length of surgery was 127 minutes compared to 149 minutes with the open techniques. Length of hospitalization at our institution was 1 postoperative day compared to an average of 3 days with open techniques. No drains were used with the endoscopic techniques, and all of the open procedures had two drains placed. The perioperative rate of morbidity for the intracorporal abdominoplasty was 15 percent (13 of 85 patients) and with the open abdominoplasty cases it was 24 percent (6 of 25 patients). Our conclusion is that the endoscopic intracorporal abdominoplasty reduces operative scars and effectively plicates the rectus fascia, thereby reducing abdominal wall laxity. It has a rate of morbidity in a skilled laparoscopist's hands no greater than with traditional open abdominoplasty. C1 USN, Med Ctr, Dept Plast & Reconstruct Surg, Washington, DC 20350 USA. USN, Med Ctr, Dept Gen Surg, Washington, DC 20350 USA. RP Zukowski, ML (reprint author), Zukowski Ctr Cosmet Plast Surg, 3612 W Lake Ave, Wilmette, IL 60091 USA. NR 42 TC 12 Z9 12 U1 0 U2 2 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 AUG PY 1998 VL 102 IS 2 BP 516 EP 527 DI 10.1097/00006534-199808000-00037 PG 12 WC Surgery SC Surgery GA 106LE UT WOS:000075130100038 PM 9703093 ER PT J AU Holmes, EK Mateczun, JM Lall, R Wilcove, GL AF Holmes, EK Mateczun, JM Lall, R Wilcove, GL TI Pilot study of suicide risk factors among personnel in the United States Marine Corps (Pacific forces) SO PSYCHOLOGICAL REPORTS LA English DT Article ID SAN-DIEGO SUICIDE; MILITARY; YOUNG AB Risk factors for suicide among active-duty members of the United States Marine Corps were investigated. Three groups were suicide attempters (n = 172), completers (n=22), and a nonpsychiatric comparison group (n=384). A series of multiple regression and discriminant analyses were conducted to assess whether any of 137 selected risk-factors differentiated the suicidal group from the comparison group. The following factors differentiated suicide attempters and completers from the comparison group and were associated with increased suicide risk: History of Abuse, Neglect, or Rejection, Lower Performance Evaluation, Symptoms of Depression, No History of Gambling Behavior, Younger Age, History of Alcohol Abuse, and Hopelessness. A discriminant analysis using these seven variables resulted in a 77% accuracy rate. When evaluating variables that could be obtained by a review of military records alone, three variables differentiated the attempters and completers from die comparison group, Lower Performance Evaluation, Younger Age, and a History of Military or Legal Problems. These variables correctly classified 73% of the sample. Implications for suicide-risk assessment for individuals in the Marine Corps are provided. C1 USN Acad, Leadership Eth & Law Dept, Annapolis, MD 21402 USA. USN, Personnel, Ctr Res & Dev, Washington, DC USA. US Dept Def, Washington, DC USA. RP Holmes, EK (reprint author), USN Acad, Leadership Eth & Law Dept, 112 Cooper Rd, Annapolis, MD 21402 USA. EM ekholmes@nadn.navy.mil NR 13 TC 14 Z9 14 U1 0 U2 2 PU PSYCHOLOGICAL REPORTS PI MISSOULA PA P O BOX 9229, MISSOULA, MT 59807 USA SN 0033-2941 J9 PSYCHOL REP JI Psychol. Rep. PD AUG PY 1998 VL 83 IS 1 BP 3 EP 11 DI 10.2466/PR0.83.5.3-11 PG 9 WC Psychology, Multidisciplinary SC Psychology GA 120VB UT WOS:000075977100001 PM 9775659 ER PT J AU McKibben, WP Bagnuolo, WG Gies, DR Hahula, ME Hartkopf, WI Roberts, LC Bolton, CT Fullerton, AW Mason, BD Penny, LR Thaller, ML AF McKibben, WP Bagnuolo, WG Gies, DR Hahula, ME Hartkopf, WI Roberts, LC Bolton, CT Fullerton, AW Mason, BD Penny, LR Thaller, ML TI A long-period spectroscopic binary in the O-star multiple system HD193322 SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID RUNAWAY STARS; RADIAL-VELOCITIES; FREQUENCY; CLUSTERS; SPECTRUM AB We present radial velocity measurements and a single-lined spectroscopic orbit for the bright O-type star, HD 193322A, which we shaw to be a 311 day binary system that has a distant third companion (detected by speckle interferometry) in a 31 yr orbit. We suggest that the speckle companion appears in the spectrum as a broad-lined component of early B type. We also present a spectrum of the visual companion, HD 193322B, which appears to be an unresolved, double-lined spectroscopic binary. Thus, HD 193322, the central object in the open cluster Collinder 419, is a multiple system that contains at least five stars (possibly seven if the C and D components are physical). Such systems may play a key role in the dynamical ejection of runaway stars from young clusters. C1 Emory Univ, Oxford Coll, Oxford, GA 30054 USA. Georgia State Univ, Ctr High Angular Resolut Astron, Atlanta, GA 30303 USA. Univ Toronto, David Dunlap Observ, Richmond Hill, ON L4C 4Y6, Canada. Univ Victoria, Dept Phys & Astron, Victoria, BC V8W 3P6, Canada. USN Observ, Astrometry Dept, Washington, DC 20392 USA. Coll Charleston, Dept Phys, Charleston, SC 29425 USA. CALTECH, Pasadena, CA 91125 USA. RP McKibben, WP (reprint author), Emory Univ, Oxford Coll, Oxford, GA 30054 USA. EM maxwpm@emory.edu; bagnuolo@chara.gsu.edu; gries@chara.gsu.edu; hahula@systems.gec.com; hartkopf@chara.gsu.edu; lewis@chara.gsu.edu; bolton@astro.utoronto.ca; awf@pha.jhu.edu; bdm@crux.usno.navy.mil; pennyl@cofc.edu; thaller@ipac.caltech.edu NR 31 TC 12 Z9 12 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD AUG PY 1998 VL 110 IS 750 BP 900 EP 905 DI 10.1086/316211 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 113WW UT WOS:000075577700003 ER PT J AU Corley, MC Westerberg, N Elswick, RK Connell, D Neil, J Sneed, G Witcher, V AF Corley, MC Westerberg, N Elswick, RK Connell, D Neil, J Sneed, G Witcher, V TI Rationing organs using psychosocial and lifestyle criteria SO RESEARCH IN NURSING & HEALTH LA English DT Article DE health care rationing; ethics; transplant criteria ID TRANSPLANT CANDIDATES; HEART; SELECTION; OUTCOMES; LIVER AB The role of patient psychosocial and lifestyle characteristics in decisions about the allocation of scarce health care resources has not been examined. In this national survey using the Criteria for Selection of Transplant Recipient (CSTR) Scale, organ transplant coordinators (N = 559) identified the psychosocial and lifestyle criteria they believe should be considered in patient selection/rejection for organ transplant. Using factor analysis to reduce the data, six factors were identified: current lifestyle/psychiatric problems, family/socioeconomic issues, habits, controlled lifestyle/psychiatric issues, cost, and stigmatized conditions. Patients who were in prison for a serious crime, used cocaine, had AIDS, or were HIV positive (criteria making up the Stigma factor), were more likely to be labeled for exclusion from transplant than those with other psychosocial/lifestyle characteristics. When transplant coordinators perceived that patients' psychosocial and lifestyle problems were under control or corrected, they were more likely to consider them for a transplant. For all but the cost factor, criteria were most stringent for heart transplants. Although over 90% of the coordinators assessed patients and participated in patient selection for transplant, master's prepared nurses were more likely than nurses with other educational preparation to be involved in organ recipient selection. These findings can serve as a prototype for how decisions are made for allocating other scarce health care resources. (C) 1998 John Wiley & Sons, Inc. C1 Virginia Commonwealth Univ, Sch Med, Richmond, VA 23298 USA. Virginia Commonwealth Univ, Survey Res Lab, Richmond, VA 23284 USA. Virginia Commonwealth Univ, Sch Nursing, Richmond, VA 23298 USA. Med Coll Virginia Hosp, Ambulatory Care Serv, Richmond, VA 23298 USA. USN, Norfolk, VA 23501 USA. RP Corley, MC (reprint author), Virginia Commonwealth Univ, Sch Med, Box 980567, Richmond, VA 23298 USA. NR 22 TC 10 Z9 10 U1 3 U2 5 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0160-6891 J9 RES NURS HEALTH JI Res. Nurs. Health PD AUG PY 1998 VL 21 IS 4 BP 327 EP 337 DI 10.1002/(SICI)1098-240X(199808)21:4<327::AID-NUR5>3.0.CO;2-H PG 11 WC Nursing SC Nursing GA 101JH UT WOS:000074865500006 PM 9679809 ER PT J AU Dalton, JH AF Dalton, JH TI Law of the Sea Treaty: Advice, consent and impact SO SEA TECHNOLOGY LA English DT Editorial Material C1 USN, Washington, DC 20350 USA. RP Dalton, JH (reprint author), USN, Washington, DC 20350 USA. NR 0 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 AUG PY 1998 VL 39 IS 8 BP 137 EP 137 PG 1 WC Engineering, Ocean SC Engineering GA 113YV UT WOS:000075582300031 ER PT J AU Snow, ES Campbell, PM Rendell, RW Buot, FA Park, D Marrian, CRK Magno, R AF Snow, ES Campbell, PM Rendell, RW Buot, FA Park, D Marrian, CRK Magno, R TI A metal/oxide tunnelling transistor SO SEMICONDUCTOR SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 2nd International Workshop on Surfaces and Interfaces of Mesoscopic Devices CY DEC 07-12, 1997 CL MAUI, HAWAII SP Arizona State Univ, Off Naval Res ID FABRICATION AB We have fabricated a new type of nanometre-scale transistor that operates by using a gate field to modulate the tunnelling probability of electrons through a lateral metal/oxide tunnel junction. Computer simulations predict that such a tunnelling transistor should have operating characteristics similar to those of a Si MOSFET but should be scalable to similar to 10 nm gate lengths. The device is composed entirely of noncrystalline materials, thus facilitating fabrication on a variety of substrates and multilayer stacking of devices for three-dimensional circuit architectures. Our initial devices have a 40 nm wide Ti/TiOx tunnel junction on top of a planar Al2O3/Al buried gate. Application of gate bias results in an order of magnitude modulation of the source-drain tunnelling current at 77 K. However, the device transconductance is smaller than predicted by modelling, which we attribute to the gate field not fully penetrating to the active region of the tunnel junction. C1 USN, Res Lab, Washington, DC 20375 USA. RP Snow, ES (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 15 TC 21 Z9 21 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0268-1242 J9 SEMICOND SCI TECH JI Semicond. Sci. Technol. PD AUG PY 1998 VL 13 IS 8A SU S BP A75 EP A78 DI 10.1088/0268-1242/13/8A/023 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA 111MY UT WOS:000075442600023 ER PT J AU Pick, M Maia, D Kerdraon, A Howard, R Brueckner, GE Michels, DJ Paswaters, S Schwenn, R Lamy, P Llebaria, A Simnett, G Lanzerotti, LJ Aurass, H AF Pick, M Maia, D Kerdraon, A Howard, R Brueckner, GE Michels, DJ Paswaters, S Schwenn, R Lamy, P Llebaria, A Simnett, G Lanzerotti, LJ Aurass, H TI Joint Nancay radioheliograph and LASCO observations of coronal mass ejections SO SOLAR PHYSICS LA English DT Article ID PARTICLE EVENT; NOISE STORM; RADIO; ULYSSES; ORIGIN; FLARE AB The development of a coronal mass ejection on 9 July 1996 has been analyzed by comparing the observations of the LASCO/SOHO coronagraphs with those of the Nancay radioheliograph. The spatial and temporal evolution of the associated I radioburst is complex and involves a long-duration continuum. The analysis of the time sequence of the radio continuum reveals the existence of distinct phases associated with distinct reconnection processes and magnetic restructuring of the corona. Electrons are accelerated in association with these reconnection processes. An excellent spatial association is found between the position and extension of the radio source and the CME seen by LASCO. Furthermore, it is shown that the topology and evolution of the source of the radio continuum involve successive interactions between two systems of loops. These successive interactions lead to magnetic reconnection, then to a large scale coronal restructuring. Thus electrons of coronal origin may have access to the interplanetary medium in a large range of heliographic latitudes as revealed by the Ulysses observations. C1 Observ Meudon, DASOP, URA CNRS 2080, F-92195 Meudon, France. USN, Res Lab, Washington, DC 20375 USA. Max Planck Inst Aeron, Lindau, Germany. CNRS, Astron Spatiale Lab, F-13012 Marseille, France. Univ Birmingham, Sch Phys & Space Res, Space Res Grp, Birmingham B15 2TT, W Midlands, England. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Inst Astrophys, Potsdam, Germany. Univ Nova Lisboa, Fac Ciencias, P-1200 Lisbon, Portugal. RP Pick, M (reprint author), Observ Meudon, DASOP, URA CNRS 2080, F-92195 Meudon, France. OI Maia, Dalmiro/0000-0001-7855-1919 NR 25 TC 31 Z9 32 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 AUG PY 1998 VL 181 IS 2 BP 455 EP 468 DI 10.1023/A:1005066817482 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 123AY UT WOS:000076104700015 ER PT J AU Kallen, AJ Wallace, MR AF Kallen, AJ Wallace, MR TI Atypical Pneumocystis carinii infection in AIDS: Massive cervical lymphadenitis and fever of unknown origin SO SOUTHERN MEDICAL JOURNAL LA English DT Article AB Pulmonary Pneumocystis carinii infections are relatively common in patients with the acquired immunodeficiency syndrome (AIDS), Extrapulmonary pneumocystis is a less common manifestation, particularly when it occurs without concurrent Pneumocystis cariniii pneumonia. Disseminated pneumocystis is most commonly found in lymph nodes, the liver, and the spleen and may result in nonspecific debilitating illness, which is often overlooked in the absence of pulmonary symptoms. We present the case of an AIDS patient who had massive cervical pneumocystis lymphadenitis and minimal pulmonary infiltrates of undetermined etiology and a clinical picture of severe wasting and fever of unknown origin. C1 USN, Med Ctr, Dept Internal Med, Div Infect Dis & Clin Res, San Diego, CA 92152 USA. RP Kallen, AJ (reprint author), USN, Med Ctr, Dept Clin Res, USNR, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 6 TC 4 Z9 4 U1 0 U2 0 PU SOUTHERN MEDICAL ASSN PI BIRMINGHAM PA 35 LAKESHORE DR PO BOX 190088, BIRMINGHAM, AL 35219 USA SN 0038-4348 J9 SOUTHERN MED J JI South.Med.J. PD AUG PY 1998 VL 91 IS 8 BP 759 EP 760 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 110HR UT WOS:000075375800012 PM 9715224 ER PT J AU Stellman, CM Bucholtz, F AF Stellman, CM Bucholtz, F TI Suppression of fluorescence interference via wavelength shift-keyed Raman spectroscopy using an argon ion laser and acousto-optic tunable filter SO SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY LA English DT Article DE Raman spectroscopy; fluorescence rejection; AOTF; wavelength modulation; wavelength shift-keying; derivative spectroscopy ID MODULATION; REJECTION; LUMINESCENCE; SCATTERING AB A wavelength shift-keyed (WSK) Raman spectrometer with argon ion laser excitation, acousto-optic tunable filter (AOTF) wavelength modulation, and synchronous photon counting detection has been developed. It has been demonstrated that this novel approach to wavelength modulation spectroscopy results in suppression of unwanted fluorescence background while giving a substantial increase in signal-to-background over non modulation techniques. The relatively low cost, lack of complexity, and durability of the described system increases the utility of shift-keyed Raman spectroscopy to a broader base of users and 'real world' applications. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Bucholtz, F (reprint author), USN, Res Lab, Div Opt Sci, Code 5606,4555 Overlook Ave, Washington, DC 20375 USA. EM mcncsby@arl.mil NR 27 TC 10 Z9 10 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1386-1425 J9 SPECTROCHIM ACTA A JI Spectroc. Acta Pt. A-Molec. Biomolec. Spectr. PD AUG PY 1998 VL 54 IS 8 BP 1041 EP 1047 DI 10.1016/S1386-1425(98)00015-8 PG 7 WC Spectroscopy SC Spectroscopy GA ZZ118 UT WOS:000074697500002 ER PT J AU Solka, JL Wegman, EJ Priebe, CE Poston, WL Rogers, GW AF Solka, JL Wegman, EJ Priebe, CE Poston, WL Rogers, GW TI Mixture structure analysis using the Akaike Information Criterion and the bootstrap SO STATISTICS AND COMPUTING LA English DT Article DE AIC; bootstrap; cluster analysis; mixture models ID PARAMETER-ESTIMATION; MAXIMUM LIKELIHOOD; CLUSTER-ANALYSIS; INCOMPLETE DATA; EM ALGORITHM; NUMBER AB Given i.i.d. observations x(1),x(2),x(3),...x(n) drawn from a mixture of normal terms, one is often interested in determining the number of terms in the mixture and their defining parameters. Although the problem of determining the number of terms is intractable under the most general assumptions, there is hope of elucidating the mixture structure given appropriate caveats on the underlying mixture. This paper examines a new approach to this problem based on the use of Akaike Information Criterion (AIC) based pruning of data driven mixture models which are obtained from resampled data sets. Results of the application of this procedure to artificially generated data sets and a real world data set are provided. C1 USN, Dahlgren Div, Ctr Surface Warfare, Syst Res & Technol Dept,Adv Computat Technol Grp, Dahlgren, VA 22448 USA. George Mason Univ, Ctr Computat Stat, Fairfax, VA 22030 USA. Johns Hopkins Univ, Dept Math Sci, Baltimore, MD 21218 USA. EM jsolka@nswc.navy.mil RI Priebe, Carey E./A-3305-2010 NR 32 TC 7 Z9 7 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0960-3174 J9 STAT COMPUT JI Stat. Comput. PD AUG PY 1998 VL 8 IS 3 BP 177 EP 188 DI 10.1023/A:1008924323509 PG 12 WC Computer Science, Theory & Methods; Statistics & Probability SC Computer Science; Mathematics GA 128RH UT WOS:000076419800001 ER PT J AU Kinney, MA AF Kinney, MA TI Women's soccer strength and conditioning for an inaugural year SO STRENGTH AND CONDITIONING LA English DT Article C1 USN Acad, Annapolis, MD 21402 USA. RP Kinney, MA (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU HUMAN KINETICS PUBL INC PI CHAMPAIGN PA 1607 N MARKET ST, CHAMPAIGN, IL 61820-2200 USA SN 1073-6840 J9 STRENGTH COND JI Strength Cond. PD AUG PY 1998 VL 20 IS 4 BP 67 EP 70 DI 10.1519/1073-6840(1998)020<0067:WSSSAC>2.3.CO;2 PG 4 WC Sport Sciences SC Sport Sciences GA 110HP UT WOS:000075375600016 ER PT J AU Froimowitz, M Wu, KM George, C VanDerveer, D Shi, Q Deutsch, HM AF Froimowitz, M Wu, KM George, C VanDerveer, D Shi, Q Deutsch, HM TI Crystal structures of analogs of threo-methylphenidate SO STRUCTURAL CHEMISTRY LA English DT Article DE methylphenidate; crystal structures; MM2-87; conformation; global minimum ID DOPAMINE REUPTAKE BLOCKERS; CONFORMATIONAL-ANALYSIS; COCAINE; CFT AB The crystal structures of the chloride salts of five analogs of threo-methylphenidate have been obtained. Four of these have different substituents on the phenyl ring while the fifth is the ethyl ester of methylphenidate. All five structures have similar three-dimensional conformations and these are compared with the global minimum obtained by MM2-87 calculations. There is good agreement between the crystal structures and the computed global minimum with the major difference being the presence of a chloride counterion in the crystal structures that prevents the carbonyl oxygen from approaching the equatorial ammonium hydrogen as closely as in the computed global minimum. C1 Pharm Eco Labs, Lexington, MA 02173 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. RP Froimowitz, M (reprint author), Pharm Eco Labs, 128 Spring St, Lexington, MA 02173 USA. EM markf@pharmeco.com NR 11 TC 8 Z9 8 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1040-0400 J9 STRUCT CHEM JI Struct. Chem. PD AUG PY 1998 VL 9 IS 4 BP 295 EP 303 DI 10.1023/A:1022435131188 PG 9 WC Chemistry, Multidisciplinary; Chemistry, Physical; Crystallography SC Chemistry; Crystallography GA 120PR UT WOS:000075965200007 ER PT J AU Chavko, M Braisted, JC Harabin, AL AF Chavko, M Braisted, JC Harabin, AL TI Effect of MK-801 on seizures induced by exposure to hyperbaric oxygen: Comparison with AP-7 SO TOXICOLOGY AND APPLIED PHARMACOLOGY LA English DT Article DE oxygen toxicity; convulsions; glutamate; NMDA-receptors; cerebral blood flow; laser Doppler flowmetry ID CEREBRAL BLOOD-FLOW; NMDA RECEPTOR ANTAGONIST; AMINO-ACID; GLUCOSE-UTILIZATION; RATS; ANTICONVULSANT; TOXICITY; CORTEX; NEUROTOXICITY; PHENCYCLIDINE AB The effect of the noncompetitive(1) N-methyl-D-aspartate (NMDA)-receptor antagonist MK-801 on seizures induced by hyperbaric oxygen in relation to changes in cerebral blood flow (CBF) was investigated. Rats were injected with MK-801 (0.005-8 mg/kg) 30 min before exposure to 100% O-2 at 5 atm (gauge pressure). MK-801 administration resulted in a biphasic response in seizure latency. Doses of 0.1-4 mg/kg significantly decreased time to EEG and motor seizures, while 8 mg/kg had no effect on seizure latency. MK-801 had no effect on seizure duration. In a dose range 0.1-8 mg/kg MK-801 increased CBF in awake animals, which might be responsible for the decreased seizure latency. The gradual increase in seizure latency with increasing MK-801 doses suggests involvement of an additional factor probably related to the drug's anticonvulsive effect. Unlike MK-801, a competitive NMDA receptor antagonist, AP-7, at a dose 250 mg/kg had no effect on latency to seizures or CBF. C1 USN, Med Res Inst, Bethesda, MD 20889 USA. RP Chavko, M (reprint author), USN, Med Res Inst, Bethesda, MD 20889 USA. NR 39 TC 10 Z9 11 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0041-008X J9 TOXICOL APPL PHARM JI Toxicol. Appl. Pharmacol. PD AUG PY 1998 VL 151 IS 2 BP 222 EP 228 DI 10.1006/taap.1998.8447 PG 7 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA 117BQ UT WOS:000075760600002 PM 9707498 ER PT J AU Dave, PR Duddu, R Li, JC Surapaneni, R Gilardi, R AF Dave, PR Duddu, R Li, JC Surapaneni, R Gilardi, R TI Photodimerization of N-acetyl-2-azetine: Synthesis of syn-diazatricyclooctane and anti-diazatricyclooctane (diaza-3-ladderane) SO TETRAHEDRON LETTERS LA English DT Article ID 2-AZETINES; ENAMIDES AB Photodimerization of N-acetyl-2-azetine to yield both possible head to head dimers with syn and anti geometries is described. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 ARDEC, Geoctr Inc, Picatinny Arsenal, NJ 07806 USA. USA, ARDEC, Picatinny Arsenal, NJ 07806 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Dave, PR (reprint author), ARDEC, Geoctr Inc, Bldg 3028, Picatinny Arsenal, NJ 07806 USA. NR 13 TC 18 Z9 18 U1 1 U2 4 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 JUL 30 PY 1998 VL 39 IS 31 BP 5481 EP 5484 DI 10.1016/S0040-4039(98)01138-1 PG 4 WC Chemistry, Organic SC Chemistry GA 100TP UT WOS:000074831700009 ER PT J AU Boos, JB Yang, MJ Bennett, BR Park, D Kruppa, W Yang, CH Bass, R AF Boos, JB Yang, MJ Bennett, BR Park, D Kruppa, W Yang, CH Bass, R TI 0.1 mu m AlSb/InAs HEMTs with InAs subchannel SO ELECTRONICS LETTERS LA English DT Article AB AlSb/InAs HEMTs with a 0.1 mu m gate length have been fabricated with a thin InAs subchannel separated from the InAs channel by 30 Angstrom of AlSb. As a result, these HEMTs exhibit improved charge control and a higher current-gain cutoff frequency. The devices have a microwave transconductance of 850 mS/mm and an f(T) of 180 GHz at V-DS = 0.6 V. After subtracting the gate bonding pad capacitance, an f(T) of 250 GHz was obtained. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 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 7 TC 39 Z9 40 U1 0 U2 0 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 JUL 23 PY 1998 VL 34 IS 15 BP 1525 EP 1526 DI 10.1049/el:19981064 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 109TN UT WOS:000075339500060 ER PT J AU Karle, IL Ranganathan, D Haridas, V AF Karle, IL Ranganathan, D Haridas, V TI Adamantane-constrained novel cyclodepsipeptides: Crystal structure and self-assembling properties of cyclo(Adm-Ser)(2) and cyclo(Adm-Ser-Xaa)(2), Xaa=Val/Ser SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID HIGH-AFFINITY LIGANDS; CONFORMATIONAL-ANALYSIS; CYCLIC HEXAPEPTIDES; PEPTIDES; GPIIB/IIIA; TENDAMISTAT; CHANNELS; PROTEINS; FAMILY; DESIGN AB Crystallographic studies on three members of a novel class of cyclodepsipeptides, containing adamantane units in the cyclic framework, are described. While the 18-membered cyclo(Adm-Ser)(2) (1) shows a simple structure with no internal hydrogen bonds, the higher members, cyclo(Adm-Ser-Val)(2) (2) and cyclo(Adm-Ser-Ser)(2), (3), exhibit interesting secondary structural features in the solid state. The two boat-shaped conformers of 2 assemble in a head-to-head fashion, giving rise to dimeric structures with water-filled channels, and show ion-transport properties. The molecule 3 revealed a unique intramolecular antiparallel beta-sheet formed by complementary hydrogen bonding between the backbone NH groups and the side chain ester carbonyls. The self-assembly patterns in the solid state are a hydrogen-bonded chain in 1 and infinite ribbons in 2 and 3. C1 USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. CSIR, Reg Res Lab, Biomol Res Unit, Trivandrum 695019, Kerala, India. RP Karle, IL (reprint author), USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RI V, haridas/K-2992-2012; TVM, NIIST/E-5132-2012 OI TVM, NIIST/0000-0002-5814-466X NR 24 TC 11 Z9 11 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 JUL 22 PY 1998 VL 120 IS 28 BP 6903 EP 6908 DI 10.1021/ja981012b PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA 104MY UT WOS:000075019400006 ER PT J AU Martin, BD Gaber, BP Patterson, CH Turner, DC AF Martin, BD Gaber, BP Patterson, CH Turner, DC TI Direct protein microarray fabrication using a hydrogel "stamper" SO LANGMUIR LA English DT Letter ID ANTIBODIES; SURFACES; IMMOBILIZATION; GOLD AB Micropatterned arrays of active proteins are vital to the next generation of high-throughput multiplexed biosensors and advanced medical diagnostics. We have developed a simple method for fabricating antibody arrays using a micromolded hydrogel "stamper" and an aminosilylated receiving surface. The stamping procedure permits direct protein deposition and micropatterning while avoiding cross-contamination of separate patterned regions. Three different antibodies were stamped in adjacent arrays of 50-80 mu m circular areas with retention of activity. I-125 labeling and atomic force microscopy studies showed that the stamper deposited protein as a submonolayer. The fluorescent signal-to-background ratio of labeled bound antigen was greater than 25:1. C1 USN, Res Lab, Washington, DC 20375 USA. RP Martin, BD (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 29 TC 130 Z9 134 U1 3 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JUL 21 PY 1998 VL 14 IS 15 BP 3971 EP 3975 DI 10.1021/la9713311 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 103ME UT WOS:000075159000001 ER PT J AU Mach, P Huang, CC Stoebe, T Wedell, ED Nguyen, T de Jeu, WH Guittard, F Naciri, J Shashidhar, R Clark, N Jiang, IM Kao, FJ Liu, H Nohira, H AF Mach, P Huang, CC Stoebe, T Wedell, ED Nguyen, T de Jeu, WH Guittard, F Naciri, J Shashidhar, R Clark, N Jiang, IM Kao, FJ Liu, H Nohira, H TI Surface tension obtained from various smectic free-standing films: The molecular origin of surface tension SO LANGMUIR LA English DT Article ID LIQUID-CRYSTAL FILMS; MESOGENIC COMPOUNDS; THIN-FILMS; TRANSITIONS; COADSORPTION; MONOLAYERS; THIOLS; LENGTH; CHAIN; GOLD AB High-resolution surface tension measurements have been carried out on the free-standing films of more than 30 selected liquid-crystal compounds in their smectic phases. Surface tension (gamma) values falling into major categories of 27, 24, 21, 13, and 11.5 dyn/cm have been obtained. The dependence of gamma on specific terminal groups or molecular structures will be discussed. Our results provide important information about the molecular origin of surface tension. C1 Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Univ Bordeaux 1, Ctr Rech Paul Pascal, CNRS, F-33600 Pessac, France. FOM, Inst Atom & Mol Phys, NL-1098 SJ Amsterdam, Netherlands. Univ Nice, Lab Chem Organ Fluor, F-06108 Nice 2, France. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Natl Sun Yat Sen Univ, Dept Phys, Kaohsiung 80424, Taiwan. Saitama Univ, Dept Appl Chem, Urawa, Saitama 338, Japan. RP Huang, CC (reprint author), Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. EM huang001@tc.umn.edu RI LIU, liuhong/F-9967-2010; Clark, Noel/E-9011-2010; OI Guittard, Frederic/0000-0001-9046-6725 NR 49 TC 43 Z9 43 U1 3 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JUL 21 PY 1998 VL 14 IS 15 BP 4330 EP 4341 DI 10.1021/la980224j PG 12 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 103ME UT WOS:000075159000053 ER PT J AU Sydor, M Arnone, RA Gould, RW Terrie, GE Ladner, SD Wood, CG AF Sydor, M Arnone, RA Gould, RW Terrie, GE Ladner, SD Wood, CG TI Remote-sensing technique for determination of the volume absorption coefficient of turbid water SO APPLIED OPTICS LA English DT Article ID APPARENT OPTICAL-PROPERTIES; INHERENT; OCEAN AB We use remote-sensing reflectance from particulate R-rs, to determine the volume absorption coefficient a of turbid water in the 400 < lambda < 700-nm spectral region. The calculated and measured values of a(lambda) show good agreement for 0.5 < a < 10 (m(-1)). To determine R-rs, from a particulate, we needed to make corrections for remote-sensing reflectance owing to surface roughness S-rs,. We determined the average spectral distribution of S-rs, from the difference in total remote-sensing reflectance measured with and without polarization. The spectral shape of S-rs, showed an excellent fit to theoretical formulas for glare based on Rayleigh and aerosol scattering from the atmosphere. (C) 1998 Optical Society of America. C1 Univ Minnesota, Dept Phys, Duluth, MN 55812 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Planning Syst Inc, Slidell, LA 70458 USA. RP Sydor, M (reprint author), Univ Minnesota, Dept Phys, Duluth, MN 55812 USA. NR 9 TC 15 Z9 17 U1 0 U2 4 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 JUL 20 PY 1998 VL 37 IS 21 BP 4944 EP 4950 DI 10.1364/AO.37.004944 PG 7 WC Optics SC Optics GA 100RC UT WOS:000074828300061 PM 18285964 ER PT J AU Harris, HC Dahn, CC Walker, RL Luginbuhl, CB Monet, AKB Guetter, HH Stone, RC Vrba, FJ Monet, DG Pier, JR AF Harris, HC Dahn, CC Walker, RL Luginbuhl, CB Monet, AKB Guetter, HH Stone, RC Vrba, FJ Monet, DG Pier, JR TI Astrometry and photometry for two dwarf carbon stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrometry; stars : carbon; stars : individual (LHS 1075, CLS 96, LHS 1555); stars : Population II ID G77-61 AB Preliminary trigonometric parallaxes and BVI photometry are presented for two dwarf carbon stars, LP 765-18 (=LHS 1075) and LP 328-57 (=CLS 96). The data are combined with the literature values for a third dwarf carbon star, G77-61 (=LHS 1555). All three stars have very similar luminosities (9.6 < M-V < 10.0) and very similar broadband colors across the entire visual-to-near-IR (BVIJHK) wavelength range. Their visual (BVI) colors differ from all known red dwarfs, subdwarfs, and white dwarfs. In the M-V versus V-I color-magnitude diagram, they are approximately 2 mag subluminous compared to normal disk dwarfs with solar-like metallicities, occupying a region also populated by O-rich subdwarfs with -1.5 < [M/H] < -1.0. The kinematics indicate that they are members of the Galactic spheroid population The subluminosity of all three stars is due to an as yet unknown combination of (undoubtedly low) metallicity, possibly enhanced helium abundance, and unusual line blanketing in the bandpasses considered. The properties of the stars are compared with models for the production of dwarf carbon stars. C1 USN Observ, Flagstaff, AZ 86002 USA. RP Harris, HC (reprint author), USN Observ, Flagstaff, AZ 86002 USA. NR 16 TC 12 Z9 12 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 JUL 20 PY 1998 VL 502 IS 1 BP 437 EP 440 DI 10.1086/305908 PN 1 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 151WH UT WOS:000077743300037 ER PT J AU Grove, JE Strickman, MS Matz, SM Hua, XM Kazanas, D Titarchuk, L AF Grove, JE Strickman, MS Matz, SM Hua, XM Kazanas, D Titarchuk, L TI Timing noise properties of GRO J0422+32 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; gamma rays : observations; stars : individual (GRO J0422+32) ID BLACK-HOLE CANDIDATES; QUASI-PERIODIC OSCILLATIONS; TRANSIENT NOVA PERSEI; X-RAY SOURCES; CYGNUS X-1; VARIABILITY; STATE AB OSSE observed the transient black hole candidate GRO J0422+32 (XN Persei 92) between 1992 August 11 and 1992 September 17. High time resolution data were obtained in several energy bands over the similar or equal to 35-600 keV range with a timing resolution of 8 ms. Power spectra at energies below 175 keV show substantial low-frequency red noise with a shoulder at a few times 10(-2) Hz, peaked noise with characteristic frequency near 0.2 Hz, and a second shoulder at a few Hz. The frequencies of the shoulders and the peak are independent of energy and source intensity. The complex cross spectrum indicates that photons in the 75-175 keV band lag photons in the 35-60 keV band by a time roughly proportional to the inverse of the Fourier frequency. The maximum lag observed is similar or equal to 300 ms. The power and lag spectra are consistent with the production of the gamma-rays through thermal Comptonization in an extended hot corona with a power-law density profile. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Northwestern Univ, Evanston, IL 60208 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Grove, JE (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7650, Washington, DC 20375 USA. NR 34 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 JUL 20 PY 1998 VL 502 IS 1 BP L45 EP L48 DI 10.1086/311481 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 151WJ UT WOS:000077743400010 ER PT J AU Gould, RW Arnone, RA AF Gould, RW Arnone, RA TI Three-dimensional modelling of inherent optical properties in a coastal environment: coupling ocean colour imagery and in situ measurements SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID REFLECTANCE; ABSORPTION; PHYTOPLANKTON; COEFFICIENTS; CHLOROPHYLL; DEPENDENCE; PROFILE AB Three-dimensional distributions of inherent optical properties (absorption, a, scattering, b, and single-scattering albedo, omega(0)) were defined for a coastal region in the north-eastern Gulf of Mexico by coupling surface ocean colour aircraft imagery and models of vertical optical profiles. The study area encompassed the surf zone region and offshore sand bar of an open beach environment to a depth of 10 m. During the aircraft overflights, concurrent in situ depth profiles of a and b were collected along an offshore transect, modelled, and assigned to each image pixel based on water depth. The modelled a and b profiles were subsequently integrated over depth (weighted by the diffuse attenuation coefficient) to provide a 'remote sensing' estimate comparable to what the aircraft sensor would see. At each pixel in the image, these initial optical depth profiles were then iteratively adjusted until the integrated values agreed to within +/-5% of the estimates derived from a bio-optical model using the aircraft-measured water-leaving radiances. Thus, unique vertical distributions of the optical fields were defined at each pixel from the corresponding profile when convergence was achieved. The modelled optical profiles compared favourably both spatially and spectrally with measured values. The 3-D visualization of the optical fields provided insight into the biological and physical processes affecting coloured dissolved organic matter (CDOM) and particle distributions in this coastal area. C1 USN, Res Lab, Remote Sensing Applicat Branch, Stennis Space Ctr, MS 39529 USA. RP Gould, RW (reprint author), USN, Res Lab, Remote Sensing Applicat Branch, Code 7343, Stennis Space Ctr, MS 39529 USA. NR 15 TC 16 Z9 16 U1 1 U2 5 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD JUL 20 PY 1998 VL 19 IS 11 BP 2141 EP 2159 DI 10.1080/014311698214929 PG 19 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 107BZ UT WOS:000075187500010 ER PT J AU Hussain, N Church, TM Veron, AJ Larson, RE AF Hussain, N Church, TM Veron, AJ Larson, RE TI Radon daughter disequilibria and lead systematics in the western North Atlantic SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ISOTOPIC COMPOSITIONS; SURFACE MICROLAYER; VERTICAL PROFILE; PB-210; PO-210; PACIFIC; AIR; ATMOSPHERE; OCEAN; PRECIPITATION AB Concentrations of Rn-222 and (210)pb Were measured in the North Atlantic troposphere in 1989 between April 12 and 28, during the Sulfide Experiment (SEX) Cruise I, and those of Rn-222, Pb-210 and Po-210, between October 24 and November 9, during the SEX Cruise II. Concentrations of Pb-210 and Po-210 were also measured in the rain water, surface seawater, and marine microlayer collected during the SEX Cruise II. Other data used and published previously include stable lead and its isotopes [Veron et al., 1992; 1993] on parallel samples. Low R-222, contents, Of the order of 0.1 and 0.3 Bq m(-3), were found in the marine air: while continental air showed nearly 10 times higher concentrations of Rn-222. These results corroborate with the air mass trajectory analyses and continental signatures of stable lead isotopes. Significant correlation is found between Rn-222 and Pb-210 on the aerosol: indicative of excess continental Rn-222 Supporting the in growth of Pb-210 from the atmosphere, in spite of its first-order removal by precipitation. Correlation between Pb-210 and stable Pb on the aerosol and in the precipitation document the source of pollutant lead from the continental surface. Mean residence times of marine aerosol based on Pb-210 is estimated to be 5.4 +/- 1.8 days during the April cruise and 19.7+/-1.9 days during the October cruise. Corresponding deposition velocity for Pb-210 is estimated to be 1.9+/-1.9 cm s(-1)? a value that suggests the dominant role of precipitation scavenging, or aerosol scavenging by larger host phases such as dust or sea salt. Excess Po-210 activities are found on the aerosol relative to what would be expected based on Pb-210 and the aerosol residence times. In surface seawaters, deficiencies of?Po-210 are observed. Mechanisms of Po-210 enrichment in atmospheric aerosol may include enrichments from the organic components of marine microlayer, sea-salt aerosol, dust, or air-sea exchange of volatile organo-polonium species. C1 Univ Delaware, Coll Marine Studies, Newark, DE 19716 USA. USN, Res Lab, Washington, DC 20375 USA. RP Hussain, N (reprint author), Univ Delaware, Coll Marine Studies, Newark, DE 19716 USA. EM najid@udel.edu; tchurch@udel.edu; averon@cerege.fr NR 60 TC 25 Z9 27 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 20 PY 1998 VL 103 IS D13 BP 16059 EP 16071 DI 10.1029/98JD01367 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 100RB UT WOS:000074828200008 ER PT J AU Fitzgerald, JW Hoppel, WA Gelbard, F AF Fitzgerald, JW Hoppel, WA Gelbard, F TI A one-dimensional sectional model to simulate multicomponent aerosol dynamics in the marine boundary layer - 1. Model description SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CLOUD CONDENSATION NUCLEI; SEA-SALT AEROSOL; SIZE DISTRIBUTION; SULFURIC-ACID; ATMOSPHERIC CHEMISTRY; SEASONAL-VARIATIONS; NORTH-ATLANTIC; MECHANISM; PARTICLES; FLUXES AB A one-dimensional, multicomponent sectional model has been developed to simulate the temporal and vertical variations of the aerosol size distribution and composition in the marine boundary layer (MBL). An important aspect of the model is its ability to handle the transport of aerosols in an atmosphere with humidity gradients with no numerical diffusion caused by the swelling and shrinking of the particles as they move through the humidity gradients. This is achieved by rewriting the aerosol general dynamical equation (GDE) in terms of dry radius thus transferring all variations in radius caused by temporal and spatial humidity variations to the rate coefficients appearing in the equations. The model then solves the new GDE in fixed dry size sections, with the humidity dependence of the processes now included in variable coefficients. This procedure also results in correct gradient transport. A limiting assumption is that the particles equilibrate instantaneously with the ambient water vapor. This assumption limits the maximum particle size which can be treated in the model to ambient (wet) radii less than about 30 mu m. All processes currently believed to be important in shaping the MBL size distribution are included in the current version of the model. These include generation of sea-salt aerosol at the ocean surface, nucleation of new particles, coagulation, growth due to condensation of gas-phase reaction products, growth due to sulfate formation during cloud processing, precipitation scavenging, surface deposition, turbulent mixing, gravitational settling, and exchange with the free troposphere. Simple gas-phase chemistry which includes the oxidation of dimethylsulfide and SO, to sulfate is incorporated in the current version of the model. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Sandia Natl Labs, Modeling & Analysis Dept 6421, Albuquerque, NM 87185 USA. RP Fitzgerald, JW (reprint author), USN, Res Lab, Remote Sensing Div, Code 7228, Washington, DC 20375 USA. EM fitzgera@ccf.nrl.navy.mil; fgelbar@sandia.gov NR 76 TC 38 Z9 38 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 20 PY 1998 VL 103 IS D13 BP 16085 EP 16102 DI 10.1029/98JD01019 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 100RB UT WOS:000074828200010 ER PT J AU Fitzgerald, JW Marti, JJ Hoppel, WA Frick, GM Gelbard, F AF Fitzgerald, JW Marti, JJ Hoppel, WA Frick, GM Gelbard, F TI A one-dimensional sectional model to simulate multicomponent aerosol dynamics in the marine boundary layer - 2. Model application SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STRATOCUMULUS TRANSITION EXPERIMENT; CLOUD CONDENSATION NUCLEI; PARTICLE NUCLEATION; SIZE DISTRIBUTIONS; VERTICAL STRUCTURE; ATLANTIC-OCEAN; GAS-EXCHANGE; PACIFIC; ENTRAINMENT; COEFFICIENT AB The dynamics of aerosols in the marine boundary layer (MBL) are simulated with the marine boundary layer aerosol model (MARBLES), a one-dimensional, multicomponent sectional aerosol model [Fitzgerald et al., this issue; Gelbard et al., this issue]. First, to illustrate how the various aerosol processes influence the particle size distribution, the model was run with one or two processes operating on the same initial size distribution. Because of current interest in the effects of cloud processing of aerosols and exchange of aerosols with the free troposphere (FT) on marine aerosol size distributions, these two processes are examined in considerable detail. The simulations show that the effect of cloud processing (characteristic double-peaked size distribution) in the upper part of the MBL is manifested at the surface on a timescale that is much faster than changes due to exchange with the FT, assuming a typical exchange velocity of 0.6 cm s(-1). The model predicts that the FT can be a significant source of particles for the MBL in the size range of the cloud-processing minimum, between the unactivated interstitial particles and the cloud condensation nuclei (CCN) which have grown as a result of conversion of dissolved SO, to sulfate in cloud droplets. The model was also used to simulate the evolution of the aerosol size distribution in an air mass advecting from the east coast of the United States out over the ocean for up to 10 days. The modification of a continental aerosol size distribution to one that is remote marine in character occurs on a timescale of 6-8 days. Nucleation was not observed in the base case 10-day advection simulation which assumed rather typical meteorological conditions. However, significant nucleation was predicted under a more favorable (albeit, atypical) combination of conditions which included significant precipitation scavenging (5 mm h(-1) of rain for 12 hours), colder temperatures by 10 degrees C (283 K at the surface decreasing to 278 K at 1000 m) and a high DMS flux (40 mu mol m(-2) d(-1)). In a test of model self initialization, long-term (8-10 days) predictions of marine aerosol size distributions were found to be essentially independent of initial conditions. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Sandia Natl Labs, Modeling & Analysis Dept 6421, Albuquerque, NM 87185 USA. Computat Phys Inc, Fairfax, VA USA. RP Fitzgerald, JW (reprint author), USN, Res Lab, Remote Sensing Div, Code 7228, Washington, DC 20375 USA. EM fitzgera@ccf.nrl.navy.mil; marti@aveka.com; fgelbar@sandia.gov NR 39 TC 23 Z9 23 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 20 PY 1998 VL 103 IS D13 BP 16103 EP 16117 DI 10.1029/98JD01018 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 100RB UT WOS:000074828200011 ER PT J AU Gelbard, F Fitzgerald, JW Hoppel, WA AF Gelbard, F Fitzgerald, JW Hoppel, WA TI A one-dimensional sectional model to simulate multicomponent aerosol dynamics in the marine boundary layer - 3. Numerical methods and comparisons with exact solutions SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID FINITE-ELEMENT METHOD; ADVECTION EQUATION; CONDENSATION; COAGULATION; GROWTH; EVAPORATION; SYSTEMS AB We present the theoretical framework and computational methods that were used by Fitzgerald et al. [this issue (a), (b)] describing a one-dimensional sectional model to simulate multicomponent aerosol dynamics in the marine boundary layer. The concepts and limitations of modeling spatially varying multicomponent aerosols are elucidated. New numerical sectional techniques are presented for simulating multicomponent aerosol growth, settling, and eddy transport, coupled to time-dependent and spatially varying condensing vapor concentrations. Comparisons are presented with new exact solutions for settling and particle growth by simultaneous dynamic condensation of one vapor and by instantaneous equilibration with a spatially varying second vapor. C1 Sandia Natl Labs, Modeling & Anal Dept 6421, Albuquerque, NM 87185 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Gelbard, F (reprint author), Sandia Natl Labs, Modeling & Anal Dept 6421, POB 5800,Mail Stop 0739, Albuquerque, NM 87185 USA. EM fgelbar@sandia.gov; fitzgera@ccf.nrl.navy.mil NR 31 TC 7 Z9 7 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 20 PY 1998 VL 103 IS D13 BP 16119 EP 16132 DI 10.1029/98JD01017 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 100RB UT WOS:000074828200012 ER PT J AU Bates, TS Huebert, BJ Gras, JL Griffiths, FB Durkee, PA AF Bates, TS Huebert, BJ Gras, JL Griffiths, FB Durkee, PA TI International Global Atmospheric Chemistry (IGAC) project's first aerosol characterization experiment (ACE 1): Overview SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MARINE BOUNDARY-LAYER; TROPOSPHERIC SULFUR CYCLE; DIMETHYL SULFIDE; PARTICLE-SIZE; ANTHROPOGENIC AEROSOLS; GREENHOUSE GASES; CUMULUS CLOUDS; CAPE-GRIM; CLIMATE; SULFATE AB The southern hemisphere marine Aerosol Characterization Experiment (ACE 1) was the first of a series of experiments that will quantify the chemical and physical processes controlling the evolution and properties of the atmospheric aerosol relevant to radiative forcing and climate. The goals of this series of process studies are to reduce the overall uncertainty in the calculation of climate forcing by aerosols and to understand the multiphase atmospheric chemical system sufficiently to be able to provide a prognostic analysis of future radiative forcing and climate response. ACE 1, which was conducted from November 15 to December 14, 1995, over the southwest Pacific Ocean, south of Australia, quantified the chemical, physical, radiative, and cloud nucleating properties and furthered our understanding of the processes controlling the aerosol properties in this minimally polluted marine atmosphere. The experiment involved the efforts of scientists from 45 research institutes in 11 countries. C1 NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Univ Hawaii Manoa, Dept Oceanog, Honolulu, HI 96822 USA. CSIRO, Div Atmospher Res, Mordialloc, Vic 3195, Australia. CSIRO, Div Marine Res, Hobart, Tas 7000, Australia. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Bates, TS (reprint author), NOAA, Pacific Marine Environm Lab, 7600 Sand Point Way Ne, Seattle, WA 98115 USA. EM bates@pmel.noaa.gov RI Bates, Timothy/L-6080-2016 NR 52 TC 229 Z9 235 U1 6 U2 13 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 JUL 20 PY 1998 VL 103 IS D13 BP 16297 EP 16318 DI 10.1029/97JD03741 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 100RB UT WOS:000074828200026 ER PT J AU Bates, TS Kapustin, VN Quinn, PK Covert, DS Coffman, DJ Mari, C Durkee, PA De Bruyn, WJ Saltzman, ES AF Bates, TS Kapustin, VN Quinn, PK Covert, DS Coffman, DJ Mari, C Durkee, PA De Bruyn, WJ Saltzman, ES TI Processes controlling the distribution of aerosol particles in the lower marine boundary layer during the First Aerosol Characterization Experiment (ACE 1) SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CLOUD CONDENSATION NUCLEI; SIZE DISTRIBUTIONS; METEOROLOGICAL TRANSPORT; OPTICAL-PROPERTIES; NORTHEAST PACIFIC; OZONE OXIDATION; SULFUR-DIOXIDE; MID-PACIFIC; DIMETHYLSULFIDE; NUCLEATION AB The goals of the International Global Atmospheric Chemistry (IGAC) Program's First Aerosol Characterization Experiment (ACE 1) are to determine and understand the properties and controlling factors of the aerosol in the remote marine atmosphere that are relevant to radiative forcing and climate. A key question in terms of this goal and the overall biogeochemical sulfur cycle is what factors control the formation, growth, and evolution of particles in the marine boundary layer (MBL). To address this question, simultaneous measurements of dimethylsulfide (DMS), sulfur dioxide (SO2), the aerosol chemical mass size distribution, and the aerosol number size distribution from 5 to 10,000 nm diameter were made on the National Oceanic and Atmospheric Administration (NOAA) ship Discoverer. From these data we conclude that the background MBL aerosol during ACE 1 often was composed of four distinct modes: an ultrafine (UF) mode (Dp = 5-20 nm), an Aitken mode (Dp = 20-80 nm),an accumulation mode (Dp = 80-300 nm), and a coarse mode (Dp > 300 nm). The presence of UF mode particles in the MBL could be explained by convective mixing between the free troposphere (FT) and the MBL associated with cloud pumping and subsidence following cold frontal passages. There was no evidence of major new particle production in the MBL. Oceanic emissions of DMS appeared to contribute to the growth of Aitken and accumulation mode particles. Coarse mode particles were comprised primarily of sea salt. Although these particles result from turbulence at the air-sea interface, the instantaneous wind speed accounted for only one third of the variance in the coarse mode number concentration in this region. C1 NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Univ Washington, Joint Inst Study Atmosphere & Oceans, Seattle, WA 98195 USA. Univ Miami, RSMAS, Miami, FL 33124 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. Univ Toulouse 3, Lab Aerol, UMR, F-31062 Toulouse, France. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Bates, TS (reprint author), NOAA, Pacific Marine Environm Lab, 7600 Sand Point Way Ne, Seattle, WA 98115 USA. EM bates@pmel.noaa.gov; kapustin@soest.hawaii.edu; quinn@pmel.noaa.gov; covert@u.washington.edu; derek@pmel.noaa.gov; marc@aero.obs-mp.fr; durkee@nps.navy.mil; debruyn@rsmas.miami.edu; esaltzman@rsmas.miami.edu RI Bates, Timothy/L-6080-2016; Quinn, Patricia/R-1493-2016 OI Quinn, Patricia/0000-0003-0337-4895 NR 58 TC 106 Z9 107 U1 5 U2 18 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 JUL 20 PY 1998 VL 103 IS D13 BP 16369 EP 16383 DI 10.1029/97JD03720 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 100RB UT WOS:000074828200030 ER PT J AU Suhre, K Mari, C Bates, TS Johnson, JE Rosset, R Wang, Q Bandy, AR Blake, DR Businger, S Eisele, FL Huebert, BJ Kok, GL Mauldin, RL Prevot, ASH Schillawski, RD Tanner, DJ Thornton, DC AF Suhre, K Mari, C Bates, TS Johnson, JE Rosset, R Wang, Q Bandy, AR Blake, DR Businger, S Eisele, FL Huebert, BJ Kok, GL Mauldin, RL Prevot, ASH Schillawski, RD Tanner, DJ Thornton, DC TI Physico-chemical modeling of the First Aerosol Characterization Experiment (ACE 1) Lagrangian B - 1. A moving column approach SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MARINE BOUNDARY-LAYER; EQUATORIAL PACIFIC; DIMETHYL SULFIDE; OZONE; PHOTODISSOCIATION; ATMOSPHERE; SIMULATION; CLOUDS; GAS; MICROPHYSICS AB During Lagrangian experiment B (LB in the following) of the First Aerosol Characterization Experiment (ACE 1): a clean maritime air mass was followed over a period of 28 hours. During that time span, the vertical distribution of aerosols and their gas phase precursors were characterized by a total of nine aircraft soundings which were performed during three research flights that followed the trajectory of a set of marked tetroons. The objective of this paper is to study the time evolution of gas phase photochemistry in this Lagrangian framework. A box model approach to the wind shear driven and vertically stratified boundary layer is questionable, since its basic assumption of instantaneous turbulent mixing of the entire air column is not satisfied here. To overcome this obstacle, a one-dimensional Lagrangian boundary layer meteorological model with coupled gas phase photochemistry is used. To our knowledge, this is the first time that such a model is applied to a Lagrangian experiment and that enough measurements are available to fully constrain the simulations. A major part of this paper is devoted to the question of to what degree our model is able to reproduce the time evolution and the vertical distribution of the observed species. Comparison with observations of O-3, OH, H2O2, CH3OOH, DMS, and CH3I, made on the nine Lagrangian aircraft soundings shows that this is in general the case, although the dynamical simulation started to deviate from the observations on the last Lagrangian flight. In agreement with experimental findings reported by Q.Wang et al. (unpublished manuscript, 1998b), generation of turbulence in the model appears to be most sensitive to the imposed sea surface temperature. Concerning the different modeled and observed chemical species, a number of conclusions are drawn: (1) Ozone, having a relatively long photochemical lifetime in the clean marine boundary layer, is found to be controlled by vertical transport processes, in particular synoptic-scale subsidence or ascent. (2) Starting with initally constant vertical profiles, the model is able to "create'' qualitatively the vertical structure of the observed peroxides. (3) OH concentrations are in agreement with observations, both on cloudy and noncloudy days. On the first flight, a layer of dry ozone rich air topped the boundary layer. The model predicts a minimum in OH and peroxides at that altitude consistent with observations. (4) Atmospheric DMS concentrations are modeled correctly only when using the Liss and Merlivat [1986] flux parameterization, the Wanninkhof [1992] flux parameterization giving values twice those observed. To arrive at this conclusion, OH is assumed to be the major DMS oxidant, but no assumptions about mixing heights or entrainment rates are necessary in this type of model. DMS seawater concentrations are constrained by observations. C1 Univ Toulouse 3, Lab Aerol, UMR CNRS UPS 5560, F-31400 Toulouse, France. Drexel Univ, Dept Chem, Philadelphia, PA 19104 USA. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92717 USA. Univ Hawaii Manoa, Dept Meteorol, Honolulu, HI 96822 USA. Natl Ctr Atmospher Res, ACD, Boulder, CO 80307 USA. Univ Hawaii Manoa, Dept Oceanog, Honolulu, HI 96822 USA. Natl Ctr Atmospher Res, RAF, Boulder, CO 80307 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. USN, Postgrad Sch, Monterey, CA 93943 USA. RP Suhre, K (reprint author), Univ Toulouse 3, Lab Aerol, UMR CNRS UPS 5560, F-31400 Toulouse, France. EM suhk@aero.obs-mip.fr RI Prevot, Andre/C-6677-2008; Bates, Timothy/L-6080-2016; OI Prevot, Andre/0000-0002-9243-8194; Suhre, Karsten/0000-0001-9638-3912 NR 51 TC 43 Z9 43 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 20 PY 1998 VL 103 IS D13 BP 16433 EP 16455 DI 10.1029/98JD00821 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 100RB UT WOS:000074828200034 ER PT J AU Wohltjen, H Snow, AW AF Wohltjen, H Snow, AW TI Colloidal metal-insulator-metal ensemble chemiresistor sensor SO ANALYTICAL CHEMISTRY LA English DT Article ID MONOLAYERS; POLYMER AB A colloidal metal-insulator-metal ensemble chemiresistor sensor based on a monolayer stabilized metal nanocluster transducer film is described. In the example presented, the thin transducer film is composed of 2-nm gold clusters encapsulated by octanethiol monolayers and is deposited on an interdigital microelectrode. Responses to organic vapor exposures are large (resistance changes up to 2-fold or more), fast (90% response in less than 1 s), reversible, and selective. Chemiresistor sorption isotherms for toluene, tetrachloroethylene, l-propanol, and water vapors are: nonlinear and illustrate the high sensitivity and selectivity (ppm detection for toluene and tetrachloroethylene; negligible response for l-propanol and water). C1 Microsensor Syst Inc, Bowling Green, KY 42103 USA. USN, Res Lab, Washington, DC 20375 USA. RP Wohltjen, H (reprint author), Microsensor Syst Inc, 62 Corp Court, Bowling Green, KY 42103 USA. NR 15 TC 323 Z9 325 U1 6 U2 56 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 JUL 15 PY 1998 VL 70 IS 14 BP 2856 EP 2859 DI 10.1021/ac9713464 PG 4 WC Chemistry, Analytical SC Chemistry GA 100RP UT WOS:000074829400012 ER PT J AU Thompson, BJ Plunkett, SP Gurman, JB Newmark, JS St Cyr, OC Michels, DJ AF Thompson, BJ Plunkett, SP Gurman, JB Newmark, JS St Cyr, OC Michels, DJ TI SOHO/EIT observations of an Earth-directed coronal mass ejection on May 12, 1997 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TELESCOPE; MISSION AB An earth-directed coronal mass ejection (CME) was observed on May 12, 1997 by the SOHO Extreme ultraviolet Imaging Telescope (EIT). The CME; originating north of the central solar meridian, was later observed by the Large Angle Spectrometric Coronagraph (LASCO) as a "halo" CME: a bright expanding ring centered about the occulting disk. Beginning at about 04:35 UT, EIT recorded several CME signatures, including dimming regions close to the eruption, post-eruption arcade formation, and a bright wavefront propagating quasi-radially from the source region. Each of these phenomena appear to be associated with the same eruption, and the onset time of these features corresponds with the estimated onset time observed in LASCO. We discuss the correspondence of these features as observed by EIT with the structure of the CME in the LASCO data. C1 NASA, Goddard Space Flight Ctr, Space Applicat Corp, Greenbelt, MD 20771 USA. USN, Res Lab, Univ Space Res Assoc, Washington, DC 20375 USA. USN, Res Lab, Computat Phys Inc, Washington, DC 20375 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Thompson, BJ (reprint author), NASA, Goddard Space Flight Ctr, Space Applicat Corp, Code 682-3, Greenbelt, MD 20771 USA. RI Thompson, Barbara/C-9429-2012 NR 18 TC 400 Z9 409 U1 0 U2 4 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 JUL 15 PY 1998 VL 25 IS 14 BP 2465 EP 2468 DI 10.1029/98GL50429 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 101UJ UT WOS:000074886300002 ER PT J AU Webb, DF Cliver, EW Gopalswamy, N Hudson, HS St Cyr, OC AF Webb, DF Cliver, EW Gopalswamy, N Hudson, HS St Cyr, OC TI The solar origin of the January 1997 coronal mass ejection, magnetic cloud and geomagnetic storm SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID EARTH AB The magnetic cloud and geomagnetic storm on January 10-11, 1997 were associated with a halo-type Coronal Mass Ejection (CME) observed by the SOHO/LASCO coronagraphs near the sun on January 6. We summarize the solar activity related to this CME and the subsequent storm at Earth. This solar activity was remarkably weak and unimpressive. If the wide CME had not been observed, the storm would not have been forecast. Thus this case represents an extreme example of so-called "problem" magnetic storms that lack obvious surface signatures of eruptive solar activity. It supports the view that CMEs involve the destabilization of large-scale coronal structures which may or may not have associated surface activity, and that CMEs, not the surface activity, are the key causal link between solar eruptions and space weather at Earth. C1 USAF, Res Lab, VSBS, Hanscom AFB, MA 01731 USA. NASA, Goddard Space Flight Ctr, CPI, Naval Res Lab, Greenbelt, MD 20771 USA. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 229, Japan. Boston Coll, Inst Sci Res, Newton Ctr, Chestnut Hill, MA 02167 USA. Catholic Univ Amer, Washington, DC USA. Solar Phys Res Corp, Tucson, AZ USA. RP Webb, DF (reprint author), USAF, Res Lab, VSBS, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. RI Gopalswamy, Nat/D-3659-2012 NR 15 TC 61 Z9 63 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUL 15 PY 1998 VL 25 IS 14 BP 2469 EP 2472 DI 10.1029/98GL00493 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 101UJ UT WOS:000074886300003 ER PT J AU Berdichevsky, D Bougeret, JL Delaboudiniere, JP Fox, N Kaiser, M Lepping, R Michels, D Plunkett, S Reames, D Reiner, M Richardson, I Rostoker, G Steinberg, J Thompson, B von Rosenvinge, T AF Berdichevsky, D Bougeret, JL Delaboudiniere, JP Fox, N Kaiser, M Lepping, R Michels, D Plunkett, S Reames, D Reiner, M Richardson, I Rostoker, G Steinberg, J Thompson, B von Rosenvinge, T TI Evidence for multiple ejecta: April 7-11, 1997, ISTP Sun-Earth connection event SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID WIND SPACECRAFT; ENERGETIC PARTICLES; MASS EJECTIONS; SHOCKS AB Evidence is presented that the enhanced geomagnetic activity, on April 10-11, 1997, was caused by one of two ejecta that left the Sun at approximate to 14 UT on April 7. This ejecta was not directly detected at the Earth. The evidence for this interpretation is based on WIND spacecraft observations in the solar wind (SW). It is consistent with: (i) measured velocities of the coronal mass ejections from the SOHO coronagraph; (ii) the initial propagation speed of the shock generated in this event, estimation from type II radio burst observations from the WAVES instrument on WIND, and (iii) the time profile of energetic ions observed by EPACT on WIND. This locally unobserved ejecta (moving at 600 to 700 kms(-1)) generated a fast shock which accelerated ions to several tens of MeV/amu. The inferred passage of the first ejecta close to Earth (on April 10 to 11) is based on the observation of an interplanetary shock (IS) ahead of a field and plasma compressional region where the draping of the SW flow and possibly the changes in the direction of the IMF are consistent with a location northward of a faster ejecta. This ejecta was responsible for disturbed SW conditions including approximately ten hours of southward orientation of the interplanetary magnetic field (IMF) and a ram pressure many times above normal. The slower moving ejecta was directed toward Earth and was observed with WIND from about 0550 until 1500 UT on April 11. It had a strong northward IMF and produced density enhancements which elevated the ram pressure to more than four times above normal. C1 NASA, Goddard Space Flight Ctr, Space Applicat Corp, Greenbelt, MD 20771 USA. Observ Paris, DESPA, URA CNRS 264, F-92195 Meudon, France. Univ Paris 11, Inst Astrophis Spatiale, Orsay, France. USN, Res Lab, USRA, Washington, DC USA. Univ Alberta, Dept Phys, Edmonton, AB, Canada. Can Network Sp Res, Edmonton, AB, Canada. MIT, Ctr Space Res, Cambridge, MA 02139 USA. Hughes STX Corp, Greenbelt, MD 20770 USA. USN, Res Lab, Washington, DC 20375 USA. Space Applicat Corp, Greenbelt, MD 20770 USA. RP Berdichevsky, D (reprint author), NASA, Goddard Space Flight Ctr, Space Applicat Corp, MC 690, Greenbelt, MD 20771 USA. RI Thompson, Barbara/C-9429-2012; OI Richardson, Ian/0000-0002-3855-3634 NR 20 TC 30 Z9 30 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUL 15 PY 1998 VL 25 IS 14 BP 2473 EP 2476 DI 10.1029/97GL03771 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 101UJ UT WOS:000074886300004 ER PT J AU Plunkett, SP Thompson, BJ Howard, RA Michels, DJ St Cyr, OC Tappin, SJ Schwenn, R Lamy, PL AF Plunkett, SP Thompson, BJ Howard, RA Michels, DJ St Cyr, OC Tappin, SJ Schwenn, R Lamy, PL TI LASCO observations of an Earth-directed coronal mass ejection on May 12, 1997 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Coronal mass ejections (CMEs) that occur near the center of the solar disk are most likely to impact Earth. Detection of such events as 'halos' in white-light coronagraphs has been somewhat controversial in recent years. We present observations from the LASCO coronagraphs on SOHO that provide convincing evidence of the detection of an Earth-directed CME on May 12, 1997. The event began at about 04:35 UT and propagated outwards from the Sun with a projected speed of around 250 km s(-1). Using some reasonable assumptions about the geometry of the CME, we estimate the true speed to be around 600 km s(-1). The onset of the event in LASCO is coincident (to within measurement uncertainties) with an eruptive event detected in extreme ultraviolet observations of the solar disk by the SOHO EIT. This is the first reported observation of a halo CME at projected distances greater than 10 R-., with a clearly identifiable solar origin. We discuss the possibility that at least some of the enhanced brightness observed by LASCO may be due to a compressional wave propagating in the corona. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Astron Spatiale Lab, F-13376 Marseille 12, France. Max Planck Inst Aeron, D-37189 Katlenburg Lindau, Germany. Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. NASA, Goddard Space Flight Ctr, Space Applicat Corp, Greenbelt, MD USA. USN, Res Lab, Computat Phys Inc, Washington, DC USA. USN, Res Lab, Univ Space Res Assoc, Washington, DC USA. RP Plunkett, SP (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RI Thompson, Barbara/C-9429-2012 NR 8 TC 91 Z9 90 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUL 15 PY 1998 VL 25 IS 14 BP 2477 EP 2480 DI 10.1029/98GL50307 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 101UJ UT WOS:000074886300005 ER PT J AU Hudson, HS Lemen, JR St Cyr, OC Sterling, AC Webb, DF AF Hudson, HS Lemen, JR St Cyr, OC Sterling, AC Webb, DF TI X-ray coronal changes during halo CMEs SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SOLAR AB Using the Yohkoh soft X-ray images, we examine the coronal structures associated with "halo" coronal mass ejections (CMEs). These may correspond to events near solar disk center. Starting with a list of eleven confirmed halo CMEs over the time range from December 1996 through May 1997 we find seven with surface features identifiable in soft X-rays, with GOES classifications ranging from A1 to M1.3. These have a characteristic pattern of sigmoid --> arcade development. In each of these events, the pre-flare structure disrupted during the flare, leaving the appearance of compact transient coronal holes. The four remaining events had weak or indistinguishable signatures in the X-ray images. For the events for which we could see well-defined coronal changes, we confirm our previous result that the estimated mass loss inferred from the soft X-ray dimming is a small fraction of typical CME masses [Sterling & Hudson 1997]. C1 Inst Space & Astronaut Sci, Sagamihara, Kanagawa 229, Japan. Lockheed Martin Palo Alto Res Lab, Palo Alto, CA USA. NASA, Goddard Space Flight Ctr, Naval Res Lab, CPI, Greenbelt, MD 20771 USA. Computat Phys Inc, Fairfax, VA 22031 USA. Boston Coll, Inst Sci Res, Chestnut Hill, MA 02167 USA. RP Hudson, HS (reprint author), Inst Space & Astronaut Sci, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229, Japan. NR 19 TC 124 Z9 126 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUL 15 PY 1998 VL 25 IS 14 BP 2481 EP 2484 DI 10.1029/98GL01303 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 101UJ UT WOS:000074886300006 ER PT J AU Gopalswamy, N Hanaoka, Y Kosugi, T Lepping, RP Steinberg, JT Plunkett, S Howard, RA Thompson, BJ Gurman, J Ho, G Nitta, N Hudson, HS AF Gopalswamy, N Hanaoka, Y Kosugi, T Lepping, RP Steinberg, JT Plunkett, S Howard, RA Thompson, BJ Gurman, J Ho, G Nitta, N Hudson, HS TI On the relationship between coronal mass ejections and magnetic clouds SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID RADIO AB We compare the substructures of the 1997 February 07 coronal mass ejection (CME) observed near the Sun with a corresponding event in the interplanetary medium to determine the origin of magnetic clouds (MCs). We find that the eruptive prominence core of the CME observed near the Sun may not directly become a magnetic cloud as suggested by some authors and that it might instead become the "pressure pulse" following the magnetic cloud. We substantiate our conclusions using time of arrival, size and composition estimates of the CME-MC substructures obtained from ground based, SOHO and WIND observations. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Nobeyama Radio Observ, Nobeyama, Japan. MIT, Cambridge, MA USA. USN, Res Lab, Washington, DC 20375 USA. Space Applicat Corp, Greenbelt, MD USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Lockheed Martin Res Lab, Palo Alto, CA USA. Solar Phys Res Corp, Tucson, AZ USA. RP Gopalswamy, N (reprint author), NASA, Goddard Space Flight Ctr, Code 682-3,Bldg 26,Room G-1, Greenbelt, MD 20771 USA. RI Gopalswamy, Nat/D-3659-2012; Thompson, Barbara/C-9429-2012 NR 16 TC 65 Z9 66 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUL 15 PY 1998 VL 25 IS 14 BP 2485 EP 2488 DI 10.1029/98GL50757 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 101UJ UT WOS:000074886300007 ER PT J AU Kaiser, ML Reiner, MJ Gopalswamy, N Howard, RA St Cyr, OC Thompson, BJ Bougeret, JL AF Kaiser, ML Reiner, MJ Gopalswamy, N Howard, RA St Cyr, OC Thompson, BJ Bougeret, JL TI Type II radio emissions in the frequency range from 1-14 MHz associated with the April 7, 1997 solar event SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CORONAL MASS EJECTIONS; INTERPLANETARY SHOCKS; BURSTS AB We present an analysis of radio emissions associated with the April 7, 1997 solar eruptive event. The event consisted of a filament disappearance, a complex two-phase coronal mass ejection (CME), and a C6.9, 2N flare. At the same time, intermittent type II radio emissions in the frequency range 1-10 MHz, corresponding to an altitude range of 2-15 R-., were observed by the Wind/WAVES radio receiver. Using the onset times and inferred heights and speeds of the radio bursts, we considered both a CME-driven shock and a flare-associated blast wave shock as possible causes of the type II radio emissions. We conclude that some of the radio emissions in the WAVES data are associated with each shock. The type II radio emissions associated with the blast wave shock were farther from the sun than any emission of this type that has been reported previously. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Observ Paris, DESPA, F-92195 Meudon, France. USN, Res Lab, Washington, DC 20375 USA. Ratheon STX, Goddard Space Flight Ctr, Greenbelt, MD USA. Catholic Univ, Washington, DC USA. Computat Phys Inc, Fairfax, VA USA. Space Applicat Corp, Vienna, VA USA. RP Kaiser, ML (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM kaiser@lepmlk.gsfc.nasa.gov RI Gopalswamy, Nat/D-3659-2012; Thompson, Barbara/C-9429-2012 NR 22 TC 45 Z9 45 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUL 15 PY 1998 VL 25 IS 14 BP 2501 EP 2504 DI 10.1029/98GL00706 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 101UJ UT WOS:000074886300011 ER PT J AU Cane, HV Richardson, IG St Cyr, OC AF Cane, HV Richardson, IG St Cyr, OC TI The interplanetary events of January-May, 1997 as inferred from energetic particle data, and their relationship with solar events SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CORONAL MASS EJECTIONS; SHOCKS AB We use observations from the Goddard particle detectors on IMP 8 to investigate near-Earth interplanetary disturbances and the associated solar events in January-May 1997, We infer the presence of high-speed streams and ejecta (material in the solar wind associated with coronal mass ejections (CMEs) at the Sun) using depressions in the counting rate of >60 MeV/amu particles measured by the anti-coincidence guard. In addition to a sequence of high-speed streams, the guard detected four ejecta. A fifth ejecta (January 10-11), evident in solar wind observations, did not produce a particle decrease. During the study period there were five particle enhancements, indicating the occurrence of energetic CMEs at the Sun. All the particle enhancements were associated with halo CMEs observed by the SOHO LASCO coronagraphs. Five of the total of nine halo CMEs in this period impacted the Earth. None of the other similar to 120 CMEs detected by LASCO did so, Only the four CMEs associated with traditional flare signatures were also associated with >10 MeV particle increases. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Naval Res Lab, Computat Phys Inc, Greenbelt, MD 20771 USA. RP Cane, HV (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. OI Richardson, Ian/0000-0002-3855-3634 NR 12 TC 33 Z9 33 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUL 15 PY 1998 VL 25 IS 14 BP 2517 EP 2520 DI 10.1029/98GL00494 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 101UJ UT WOS:000074886300015 ER PT J AU Stanton, TP Ostrovsky, LA AF Stanton, TP Ostrovsky, LA TI Observations of highly nonlinear internal solitons over the Continental Shelf SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Surface disturbances caused by strong, near-surface internal waves are widely seen in coastal regions as bands of slick and rough water propagating shoreward. These surface slicks are typically manifestations of optical and radar backscatter properties above internal solitons, and have strong surface current pulses associated with them. During a recent experiment studying coastal internal waves, extremely strong solitary internal wave packets were observed over a three week period on a very shallow and strongly stratified pycnocline off Northern Oregon. During periods of strongest tidal forcing, solitons were consistently observed on the leading edge of a semidiurnal internal tide bore, with pycnocline displacements up to 25m downward from a 7m initial depth in the first few solitons. The extreme nonlinearity of these internal waves is believed to be unique in ocean observations. This note characterizes these highly nonlinear Solitary Internal Waves (SIW) and presents a second order KdV model which reproduces the form of the displacements, and the small change in soliton width with amplitude predicted by this model. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. Univ Colorado, CIRES, NOAA, Environm Technol Lab, Boulder, CO 80303 USA. Russian Acad Sci, Inst Appl Phys, Nizhnii Novgorod 603600, Russia. RP Stanton, TP (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. OI Ostrovsky, Lev/0000-0003-2233-1305 NR 6 TC 119 Z9 121 U1 0 U2 7 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 JUL 15 PY 1998 VL 25 IS 14 BP 2695 EP 2698 DI 10.1029/98GL01772 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 101UJ UT WOS:000074886300060 ER PT J AU Zheng, XQ Liu, CQ Liu, F Yang, CI AF Zheng, XQ Liu, CQ Liu, F Yang, CI TI Turbulent transition simulation using the k-omega model SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE turbulent transition; turbulence modelling; Navier-Stokes equation ID PRESSURE TURBINE CASCADE; NAVIER-STOKES; EQUATIONS; FLOW AB This paper describes a novel approach in simulating laminar to turbulent transition by using two-equation models. The Total Stresses Limitation (TSL) concept is used to make the two-equation model capable of predicting high-Reynolds-number transitional flow. In order to handle the transition triggered by laminar separation at a low Reynolds number location, which commonly occurs in high speed flow, a sensor is introduced to detect separation and trigger transition in the separated zone. Test cases include the classical flat-plate turbulent boundary flow, and low-pressure turbine cascade flows at design and off-design conditions. (C) 1998 John Wiley & Sons, Ltd. C1 Louisiana Tech Univ, Dept Math & Stat, Ruston, LA 71270 USA. Univ Calif Irvine, Dept Mech & Aerosp Engn, Irvine, CA 92717 USA. NSWC Bethesda, Carderock Div, Hydromech Directorate, Bethesda, MD USA. RP Zheng, XQ (reprint author), 34 Beecher Pl,2, Newton, MA 02159 USA. NR 26 TC 17 Z9 18 U1 1 U2 5 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD JUL 15 PY 1998 VL 42 IS 5 BP 907 EP 926 DI 10.1002/(SICI)1097-0207(19980715)42:5<907::AID-NME393>3.0.CO;2-T PG 20 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA ZV454 UT WOS:000074306200007 ER PT J AU Song, GB Cai, LL Wang, YP Longman, RW AF Song, GB Cai, LL Wang, YP Longman, RW TI A sliding-mode based smooth adaptive robust controller for friction compensation SO INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL LA English DT Article DE sliding-mode control; friction compensation; adaptive robust control; nonlinear control; stick-slip friction ID STICK-SLIP FRICTION; ROBOT MANIPULATORS AB In this paper, a new approach employing both adaptive and robust methodologies is proposed for stick-slip friction compensation for tracking control of a one degree-of-freedom DC-motor system. It is well known that the major components of friction are Coulomb force, viscous force, exponential force (used to model the downward bend of friction at low velocity) and position-dependent force. Viscous force is linear and Coulomb force is linear in parameter; thus, these two forces can be compensated for by adaptive feedforward cancellation. Meanwhile, the latter two forces, which are neither linear nor linear in parameters, can only be partially compensated for by adaptive feedforward cancellation. Therefore, a robust compensator with an embedded adaptive law to 'learn' the upper bounding function on-line is proposed to compensate the uncancelled exponential and position-dependent friction. Lyapunov's direct method is utilized to prove the globally asymptotic stability of the servo-system under the proposed friction compensation method. Numerical simulations are presented as illustrations. (C) 1998 John Wiley & Sons, Ltd. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. Hong Kong Univ Sci & Technol, Dept Engn Mech, Kowloon, Hong Kong. Columbia Univ, Dept Mech Engn, New York, NY 10027 USA. RP Song, GB (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. NR 18 TC 18 Z9 19 U1 0 U2 7 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1049-8923 J9 INT J ROBUST NONLIN JI Int. J. Robust Nonlinear Control PD JUL 15 PY 1998 VL 8 IS 8 BP 725 EP 739 DI 10.1002/(SICI)1099-1239(19980715)8:8<725::AID-RNC345>3.0.CO;2-D PG 15 WC Automation & Control Systems; Engineering, Electrical & Electronic; Mathematics, Applied SC Automation & Control Systems; Engineering; Mathematics GA ZZ890 UT WOS:000074778900006 ER PT J AU Melinger, JS McMorrow, D Campbell, AB Buchner, S Tran, LH Knudson, AR Curtice, WR AF Melinger, JS McMorrow, D Campbell, AB Buchner, S Tran, LH Knudson, AR Curtice, WR TI Pulsed laser-induced single event upset and charge collection measurements as a function of optical penetration depth SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GAAS-MESFETS; SEU; DEVICES; CIRCUITS; DEPENDENCE; PARAMETERS; TRANSPORT; DYNAMICS AB We use picosecond laser pulses to investigate single event upsets and related fundamental charge collection mechanisms in semiconductor microelectronic devices and circuits. By varying the laser wavelength the incident laser pulses deposit charge tracks of variable length, which form an approximation to the charge tracks resulting from high energy space particle strikes. We show how variation of the charge track length deposited by laser pulses allows the mechanisms of charge collection in semiconductor devices to be probed in a sensitive manner. With the aid of computer simulations, new insight into charge collection mechanisms for metal-semiconductor field effect transistor (MESFET) devices and heterojunction bipolar transistor devices is found. In the case of the MESFET we point out the correlation between charge collection in the device and the ensuing single event upset in the composite circuit. In favorable cases, we show how probing circuits with tunable laser pulses can estimate a charge collection depth, which is a circuit parameter important for the prediction of error rates for circuits operating in a space-radiation environment. (C) 1998 American Institute of Physics. [S0021-8979(95)00714-2] C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Landover, MD 20785 USA. WR Curtice Consulting, Princeton Junction, NJ 08550 USA. RP Melinger, JS (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM melinger@ccf.nrl.navy.mil NR 45 TC 57 Z9 58 U1 0 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 JUL 15 PY 1998 VL 84 IS 2 BP 690 EP 703 DI 10.1063/1.368124 PG 14 WC Physics, Applied SC Physics GA 108GM UT WOS:000075257800006 ER PT J AU Buot, FA Rendell, RW Snow, ES Campbell, PM Park, D Marrian, CRK Magno, R AF Buot, FA Rendell, RW Snow, ES Campbell, PM Park, D Marrian, CRK Magno, R TI Dependence of gate control on the aspect ratio in metal/metal-oxide/metal tunnel transistors SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ATOMIC-FORCE MICROSCOPE; FABRICATION; DEVICES AB The design criteria for large transconductance/high output impedance or high-gain operation of metal-oxide tunneling transistors is given. The dependence of the gate control on the aspect ratio of thickness to width of the tunneling oxide is investigated by computer simulation. This device structure can only operate similar to conventional semiconductor transistors for aspect ratio considerably less than one. It ceases to function as a transistor for larger aspect ratio due to insufficient penetration of the gate control field into the tunneling oxide. To demonstrate this, the current-voltage characteristics are computed for aspect ratios equal to 7/30, 1, 21/10, and the different tunneling-current behaviors compared with our experimental results on Ti/TiOx/Ti and Nb/NbOx/Nb tunnel transistors. [S0021-8979(98)01114-1]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Buot, FA (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 15 TC 5 Z9 5 U1 0 U2 0 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 JUL 15 PY 1998 VL 84 IS 2 BP 1133 EP 1139 DI 10.1063/1.368114 PG 7 WC Physics, Applied SC Physics GA 108GM UT WOS:000075257800070 ER PT J AU Feddersen, F Guza, RT Elgar, S Herbers, THC AF Feddersen, F Guza, RT Elgar, S Herbers, THC TI Alongshore momentum balances in the nearshore SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID LONGSHORE CURRENTS; SURF ZONE; SHEAR-STRESS; BREAKING; OCEAN; WAVES; BEACH; WIND AB The one-dimensional, time-averaged (over many wave periods) alongshore momentum balance between forcing by wind and breaking waves and the bottom stress is examined with field observations spanning a wide range of conditions on a barred beach. Near-bottom horizontal currents were measured for 2 months at 15 locations along a cross-shore transect extending 750 m from the shoreline to 8-m water depth. The hourly averaged bottom stress was estimated from observed currents using a quadratic drag law. The wave radiation stress was estimated in 8-m depth from an array of pressure sensors, and the wind stress was estimated from an anemometer at the seaward end of a nearby pier. The combined wind and wave forcing integrated ever the entire cross-shore transect is balanced by the integrated bottom stress. The wind stress contributes about one third of the forcing over the transect. Analysis of the momentum balances in different cross-shore regions shows that in the surf zone, wave forcing is much larger than wind forcing and that the bottom drag coefficient is larger in the surf zone than farther seaward, consistent with earlier studies. C1 Univ Calif San Diego, Scripps Inst Oceanog, Ctr Coastal Studies, La Jolla, CA 92093 USA. Washington State Univ, Sch Elect Engn & Comp Sci, Pullman, WA 99164 USA. USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Feddersen, F (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Ctr Coastal Studies, La Jolla, CA 92093 USA. NR 36 TC 79 Z9 80 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 JUL 15 PY 1998 VL 103 IS C8 BP 15667 EP 15676 DI 10.1029/98JC01270 PG 10 WC Oceanography SC Oceanography GA ZZ547 UT WOS:000074741000011 ER PT J AU Millis, AJ Paul, DM Battle, P Khomskii, D Edwards, DM Stroud, R Venkatesan, T Cooper, JR Littlewood, PB Pierre, J AF Millis, AJ Paul, DM Battle, P Khomskii, D Edwards, DM Stroud, R Venkatesan, T Cooper, JR Littlewood, PB Pierre, J TI The influence of magnetic field and pressure on the structural phase transition in La1-xSrxMnO3 - Discussion SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Editorial Material C1 Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Oxford, Oxford OX1 2JD, England. Univ Groningen, NL-9700 AB Groningen, Netherlands. Univ London Imperial Coll Sci Technol & Med, London, England. USN, Res Lab, Washington, DC 20375 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Cambridge, Cambridge CB2 1TN, England. CNRS, Lab Louis Neel, F-38042 Grenoble, France. RP Millis, AJ (reprint author), Johns Hopkins Univ, Baltimore, MD 21218 USA. RI Littlewood, Peter/B-7746-2008; Venkatesan, Thirumalai/E-1667-2013 NR 0 TC 0 Z9 0 U1 0 U2 3 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X J9 PHILOS T R SOC A JI Philos. Trans. R. Soc. A-Math. Phys. Eng. Sci. PD JUL 15 PY 1998 VL 356 IS 1742 BP 1559 EP 1561 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 105TK UT WOS:000075089500011 ER PT J AU Littlewood, PB Evetts, JE Gehring, GA Venkatesan, T Rzchoswki, M Stroud, R Millis, AJ AF Littlewood, PB Evetts, JE Gehring, GA Venkatesan, T Rzchoswki, M Stroud, R Millis, AJ TI Defect-induced spin disorder and magnetoresistance in single-crystal and polycrystal rare-earth manganite thin films - Discussion SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Editorial Material C1 Univ Cambridge, Cambridge CB2 1TN, England. Univ Sheffield, Sheffield S10 2TN, S Yorkshire, England. Univ Maryland, College Pk, MD 20742 USA. Univ Wisconsin, Madison, WI USA. USN, Res Lab, Washington, DC 20375 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. RP Littlewood, PB (reprint author), Univ Cambridge, Cambridge CB2 1TN, England. RI Littlewood, Peter/B-7746-2008; Venkatesan, Thirumalai/E-1667-2013 NR 0 TC 0 Z9 0 U1 0 U2 2 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X J9 PHILOS T R SOC A JI Philos. Trans. R. Soc. A-Math. Phys. Eng. Sci. PD JUL 15 PY 1998 VL 356 IS 1742 BP 1613 EP 1615 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 105TK UT WOS:000075089500017 ER PT J AU Stroud, R Venkatesan, T Blamire, M Palstra, TTM Millis, AJ Maignan, A AF Stroud, R Venkatesan, T Blamire, M Palstra, TTM Millis, AJ Maignan, A TI Manganite-based devices: opportunities, bottlenecks and challenges - Discussion SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Editorial Material C1 USN, Res Lab, Washington, DC 20375 USA. Univ Cambridge, Cambridge CB2 1TN, England. Univ Groningen, NL-9700 AB Groningen, Netherlands. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Caen, Lab CRISMAT, F-14032 Caen, France. RP Stroud, R (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Venkatesan, Thirumalai/E-1667-2013; Palstra, Thomas/K-1961-2013 OI Palstra, Thomas/0000-0001-5239-3115 NR 1 TC 0 Z9 0 U1 0 U2 2 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X J9 PHILOS T R SOC A JI Philos. Trans. R. Soc. A-Math. Phys. Eng. Sci. PD JUL 15 PY 1998 VL 356 IS 1742 BP 1678 EP 1680 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 105TK UT WOS:000075089500023 ER PT J AU Pickett, WE Erwin, SC Ethridge, EC AF Pickett, WE Erwin, SC Ethridge, EC TI Reformulation of the LDA+U method for a local-orbital basis SO PHYSICAL REVIEW B LA English DT Article ID DENSITY-FUNCTIONAL THEORY; ELECTRONIC-STRUCTURE; NIO; APPROXIMATION; INSULATORS; IMPURITIES; SPECTRA; LA2CUO4; METALS; MODEL AB We present a local orbital approach to the evaluation of the on-site repulsion energy U for use in the LDA+U method of Anisimov and co-workers. Our objectives are to make the method more firmly based, to concentrate primarily on ground-state properties rather than spectra, and to test the method in cases where only modest changes in orbital occupations are expected, as well as for highly correlated materials. Because of these objectives, we employ a differential definition of U. We also define a matrix U, which we find is very dependent on the environment of the atom in question. The formulation is applied to evaluate U for transition-metal monoxides from VO to NiO using a local-orbital basis set. The resulting values of U are typically only 40-65 % as large as values currently in use. We evaluate the U matrix for the e(g) and t(2g) subshells in paramagnetic FeO, and illustrate the very different charge responses of the e(g) and t(2g) states..The sensitivity of the method to the choice of the d orbitals, and to the basis set in general, is discussed. [S0163-1829(98)05427-7]. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Pickett, WE (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. EM pickett@physics.ucdavis.edu RI Erwin, Steven/B-1850-2009 NR 20 TC 203 Z9 203 U1 3 U2 23 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 JUL 15 PY 1998 VL 58 IS 3 BP 1201 EP 1209 DI 10.1103/PhysRevB.58.1201 PG 9 WC Physics, Condensed Matter SC Physics GA 104WT UT WOS:000075039600033 ER PT J AU Briley, A Pederson, MR Jackson, KA Patton, DC Porezag, DV AF Briley, A Pederson, MR Jackson, KA Patton, DC Porezag, DV TI Vibrational frequencies and intensities of small molecules: All-electron, pseudopotential, and mixed-potential methodologies SO PHYSICAL REVIEW B LA English DT Article ID DENSITY-FUNCTIONAL CALCULATIONS; SCATTERING-THEORETIC METHOD; TOTAL-ENERGY CALCULATIONS; PLANE-WAVE CALCULATIONS; ATOMIC ORBITALS METHOD; LINEAR COMBINATION; EFFICIENT PSEUDOPOTENTIALS; STRUCTURAL-PROPERTIES; ADAPTIVE-COORDINATE; DYNAMICS AB We describe a numerically robust strategy for implementing pseudopotentials in a way that is independent of the type of basis set employed. Applications of this method are illustrated for many small molecules and compared to all-electron calculations determined from the same computer code. In addition we introduce a mixed methodology that allows for the treatment of some atoms within an all-electron methodology and some atoms within a pseudopotential methodology. The type of bonding studied here includes both ionic and covalent systems and includes atoms from each of the first four rows of the periodic table. In addition to binding energies, structural parameters, electronic structures, and vibrational frequencies we compare vibrational intensities (e.g., Raman and infrared intensities) obtained from LDA within all-electron, mixed, and pseudopotential methodologies. We discuss issues related to timing for pseudopotentials versus all-electron when used in conjunction with local-orbital-based methods. C1 Cent Michigan Univ, Dept Phys, Mt Pleasant, MI 48859 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Georgetown Univ, Dept Phys, Washington, DC 20057 USA. RP Briley, A (reprint author), Cent Michigan Univ, Dept Phys, Mt Pleasant, MI 48859 USA. OI Jackson, Koblar/0000-0002-5342-7978 NR 61 TC 68 Z9 69 U1 1 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 JUL 15 PY 1998 VL 58 IS 4 BP 1786 EP 1793 DI 10.1103/PhysRevB.58.1786 PG 8 WC Physics, Condensed Matter SC Physics GA 104WU UT WOS:000075039700023 ER PT J AU Yang, SH AF Yang, SH TI Ab initio local-orbital density-functional method for transition metals and semiconductors SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; SURFACE RELAXATION; ELECTRONIC-STRUCTURE; GROUND-STATE; ENERGY; PT(111); HARRIS; CLUSTERS; SI AB I develop an ab initio local-orbital method for transition metals and semiconductors. The method of calculation is based on the non-self-consistent Harris functional version of the local-density approximation. In particular, I use a generalization of the method of Sankey and Niklewski to include d orbitals in the basis set, thus allowing the application to transition;metals. This method is shown to produce excellent results for the band structure of crystalline Al, Si, and Pt (as well as other transition-metal compounds). This method, along with a dynamical quenching algorithm, is employed to study Pt(lll) surface relaxation. The results of the calculations show a slight expansion of the top-layer spacing by 0.8% relative to the bulk spacing, which is in good agreement with experiment. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Yang, SH (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. NR 38 TC 6 Z9 6 U1 0 U2 0 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 JUL 15 PY 1998 VL 58 IS 4 BP 1832 EP 1838 DI 10.1103/PhysRevB.58.1832 PG 7 WC Physics, Condensed Matter SC Physics GA 104WU UT WOS:000075039700026 ER PT J AU Bryant, GW Shirley, EL Goldner, LS McDaniel, EB Hsu, JWP Tonucci, RJ AF Bryant, GW Shirley, EL Goldner, LS McDaniel, EB Hsu, JWP Tonucci, RJ TI Theory of probing a photonic crystal with transmission near-field optical microscopy SO PHYSICAL REVIEW B LA English DT Article AB While near-field scanning optical microscopy (NSOM) can provide optical images with resolution much better than the diffraction limit, analysis and interpretation of these images is often difficult. We present a theory of probing with transmission NSOM that includes the effects of tip field, tip/sample coupling, light propagation through the sample, and light collection. We apply this theory to analyze experimental NSOM images of a nanochannel glass (NCG) array obtained in transmission mode. The NCG is a triangular array of dielectric rods in a dielectric glass matrix with a two-dimensional photonic band structure. We determine the modes for the NCG photonic crystal and simulate the observed data. The calculations show large contrast at low numerical aperture (NA) of the collection optics and detailed structure at high NA consistent with the observed images. We present calculations as a function of NA to identify how the NCG photonic modes contribute to and determine the spatial structure in these images. Calculations are presented as a function of tip/sample position, sample index contrast and geometry, and aperture size to identify the factors that determine image formation with transmission NSOM in this experiment. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. USN, Res Lab, Washington, DC 20375 USA. RP Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 18 TC 21 Z9 21 U1 0 U2 1 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 JUL 15 PY 1998 VL 58 IS 4 BP 2131 EP 2141 DI 10.1103/PhysRevB.58.2131 PG 11 WC Physics, Condensed Matter SC Physics GA 104WU UT WOS:000075039700063 ER PT J AU Cho, SL DiVenere, A Wong, GK Ketterson, JB Meyer, JR Hong, JI AF Cho, SL DiVenere, A Wong, GK Ketterson, JB Meyer, JR Hong, JI TI Growth-mode modification of Bi on CdTe(111)A using Te monolayer deposition SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-BEAM EPITAXY; SURFACTANT-MEDIATED GROWTH; STRAIN RELIEF; GE; SI(001); SI(111); SUPERLATTICES; COVERAGE; SI; SB AB Bi deposited on the CdTe(lll)A (Cd-terminated) surface grows by three-dimensional (3D) islanding, while Bi deposited on the CdTe(lll)B (Te-terminated) grows layer-by-layer. However, introducing a Te monolayer (ML) on the CdTe(lll)A surface reduces the interfacial energy, thereby changing the growth mode of Bi from 3D islandlike to layer-by-layer growth. The Te ML remains where it is deposited, which differs from the growth mode in which the surface-active agent floats on the growing surface. By incorporating appropriate Te ML's, Bi/CdTe superlattices with sharper interfaces were observed. These superlattices were characterized by x-ray diffraction and transmission electron microscopy. C1 Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. Northwestern Univ, Mat Res Ctr, Evanston, IL 60208 USA. USN, Res Lab, Washington, DC 20375 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RP Cho, SL (reprint author), Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. RI HONG, JUNG-IL/B-8566-2008; Ketterson, John/B-7234-2009 OI HONG, JUNG-IL/0000-0001-7301-6693; NR 36 TC 20 Z9 20 U1 0 U2 1 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 JUL 15 PY 1998 VL 58 IS 4 BP 2324 EP 2328 DI 10.1103/PhysRevB.58.2324 PG 5 WC Physics, Condensed Matter SC Physics GA 104WU UT WOS:000075039700084 ER PT J AU Santangelo, PG Roland, CM AF Santangelo, PG Roland, CM TI Molecular weight dependence of fragility in polystyrene SO MACROMOLECULES LA English DT Article ID SEGMENTAL RELAXATION; POLYMERS; LIQUIDS; MOTION AB Segmental relaxation was measured for a series of polysytrenes (PS) of varying molecular weight. The normalized Arrhenius plots of segmental relaxation times (fragility curves) become less steep for shorter chain lengths. Since the shape of the relaxation function is invariant to molecular weight, such behavior is a deviation from the usual correlation between time and temperature dependencies. Although the dependence of relaxation times on T-g-normalized temperature is weaker (less fragile), lower molecular weight PS has a larger heat capacity change at T-g. This result is at odds with an interpretation of temperature dependencies in terms of the degrees of freedom available to the glass upon transition to the viscous liquid. 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 27 TC 175 Z9 175 U1 2 U2 32 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JUL 14 PY 1998 VL 31 IS 14 BP 4581 EP 4585 DI 10.1021/ma971823k PG 5 WC Polymer Science SC Polymer Science GA 101DE UT WOS:000074853700024 ER PT J AU Cao, XA Abernathy, CR Singh, RK Pearton, SJ Fu, M Sarvepalli, V Sekhar, JA Zolper, JC Rieger, DJ Han, J Drummond, TJ Shul, RJ Wilson, RG AF Cao, XA Abernathy, CR Singh, RK Pearton, SJ Fu, M Sarvepalli, V Sekhar, JA Zolper, JC Rieger, DJ Han, J Drummond, TJ Shul, RJ Wilson, RG TI Ultrahigh Si+ implant activation efficiency in GaN using a high-temperature rapid thermal process system SO APPLIED PHYSICS LETTERS LA English DT Article ID FIELD-EFFECT TRANSISTORS AB Si+ implant activation efficiencies above 90%, even at doses of 5 x 10(15) cm(-2), have been achieved in GaN by rapid thermal processing at 1400-1500 degrees C for 10 s. The annealing system utilizes molybdenum intermetallic heating elements capable of operation up to 1900 degrees C, producing high heating and cooling rates (up to 100 degrees C s(-1)). Unencapsulated GaN shows severe surface pitting at 1300 degrees C and complete loss of the film by evaporation at 1400 degrees C. Dissociation of nitrogen from the surface is found to occur with an approximate activation energy of 3.8 eV for GaN (compared to 4.4 eV for AlN and 3.4 eV for InN). Encapsulation with either rf magnetron reactively sputtered or metal organic molecular beam epitaxy-grown AIN thin films provides protection against GaN surface degradation up to 1400 degrees C, where peak electron concentrations of similar to 5x10(20) cm(-3) can be achieved in Si-implanted GaN. Secondary ion mass spectrometry profiling showed little measurable redistribution of Si, suggesting D(Si)less than or equal to 10(-13) cm(2) S-1 at 1400 degrees C. The implant activation efficiency decreases at higher temperatures, which may result from Si-Ga to Si-N Site switching and resultant self-compensation. (C) 1998 American Institute of Physics. [S0003-6951 (98)03828-5]. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Micropyret Heaters Int Inc, Cincinnati, OH 45212 USA. Off Naval Res, Arlington, VA 22217 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cao, XA (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 28 TC 67 Z9 67 U1 2 U2 6 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 JUL 13 PY 1998 VL 73 IS 2 BP 229 EP 231 DI 10.1063/1.121764 PG 3 WC Physics, Applied SC Physics GA 108PV UT WOS:000075275400033 ER PT J AU Miles, MH AF Miles, MH TI Cold fusion controversy SO CHEMICAL & ENGINEERING NEWS LA English DT Letter C1 Naval Air Warfare Ctr, Weapons Div, China Lake, CA USA. RP Miles, MH (reprint author), Naval Air Warfare Ctr, Weapons Div, China Lake, CA USA. NR 1 TC 0 Z9 0 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0009-2347 J9 CHEM ENG NEWS JI Chem. Eng. News PD JUL 13 PY 1998 VL 76 IS 28 BP 10 EP 11 PG 2 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 101UN UT WOS:000074886700007 ER PT J AU Arrasmith, WW Roggemann, M Welsh, B AF Arrasmith, WW Roggemann, M Welsh, B TI Optimal wave-front reconstruction for a coherent diffracted field SO APPLIED OPTICS LA English DT Article ID ADAPTIVE-OPTICS; PHASE-DIFFERENCE; LEAST-SQUARES; PERFORMANCE AB Phase differences in the far field of a coherently illuminated object are used to estimate the two-dimensional phase in the measurement plane of an imaging system. A previously derived phase-correlation function is used in a minimum-variance phase-estimation algorithm to map phase-difference measurements optimally to estimates of the phase on a grid of points in the measurement plane. Theoretical and computer-simulation comparisons between the minimum-variance phase estimator and conventional least-squares estimators are made. The minimum-variance phase estimator produces a lower aperture-averaged mean-square phase error for all values of a sampling parameter beta. (C) 1998 Optical Society of America. C1 USN Acad, Div Engn & Weap, Annapolis, MD 21402 USA. Michigan Technol Univ, Dept Elect Engn, Houghton, MI 49931 USA. USAF, Inst Technol, Dept Elect & Comp Engn, Grad Sch Engn, Wright Patterson AFB, OH 45433 USA. RP Arrasmith, WW (reprint author), USN Acad, Div Engn & Weap, Stop 14 A,590 Holloway Rd, Annapolis, MD 21402 USA. RI Arrasmith, William/G-6949-2016 OI Arrasmith, William/0000-0002-2917-9775 NR 26 TC 4 Z9 4 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 JUL 10 PY 1998 VL 37 IS 20 BP 4457 EP 4467 DI 10.1364/AO.37.004457 PG 11 WC Optics SC Optics GA ZZ393 UT WOS:000074724900017 PM 18285897 ER PT J AU Dermer, CD AF Dermer, CD TI On spectral and temporal variability in blazars and gamma-ray bursts SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL Lacertae objects : general; galaxies : jets; gamma rays : bursts; radiation mechanisms : nonthermal ID EVOLUTION; DURATION; ENERGY AB A simple model for variability in relativistic plasma outflows is studied, in which nonthermal electrons are continuously and uniformly injected in the comoving frame over a time interval Delta t. The evolution of the electron distribution is assumed to be dominated by synchrotron losses, and the energy and time dependence of the synchrotron and synchrotron self-Compton (SSC) fluxes are calculated for a power-law electron injection function with index s = 2. The mean time of a flare or pulse measured at photon energy E with respect to the onset of the injection event varies as E(-1/2) and E(-1/4) for synchrotron and SSC processes, respectively, until the time approaches the limiting intrinsic mean time (I + z)Delta t/(2D), where z is the redshift and D is the Doppler factor. This dependence is in accord with recent analyses of blazar and gamma-ray burst (GRB) emissions and suggests a method to discriminate between external Compton and SSC models of high-energy gamma radiation from blazars and GRBs. The qualitative behavior of the X-ray spectral index/flux relation observed from BL Lacertae objects can be explained with this model. This demonstrates that synchrotron losses are primarily responsible for the X-ray variability behavior and strengthens a new test for beaming from correlated hard X-ray/TeV observations. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Dermer, CD (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7653, Washington, DC 20375 USA. NR 32 TC 45 Z9 45 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 JUL 10 PY 1998 VL 501 IS 2 BP L157 EP L161 DI 10.1086/311467 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 101DG UT WOS:000074853900001 ER PT J AU Bitterwolf, TE Saygh, A Shade, JE Rheingold, AL Yap, GPA Liable-Sands, L AF Bitterwolf, TE Saygh, A Shade, JE Rheingold, AL Yap, GPA Liable-Sands, L TI Photochemistry of ring-coupled group VI bimetallic compounds I: phosphine substitution without disproportionation. The molecular structures of Mo-2(CO)(5)[P(C-6 H-5)(3)](mu-eta(5),eta(5)-C5H4-CR2-C5H4) and Mo-2(CO)(4)[P(CH3)(3)](2)(mu-eta(5),eta(5)-C5H4-CR2-C5H4) SO JOURNAL OF ORGANOMETALLIC CHEMISTRY LA English DT Article DE photolysis; bimetallic compounds; substitution reactions; phosphines ID CHEMISTRY; MECHANISM AB Solution photolysis of ring-coupled bimetallic compounds of the formula M-2(CO)(6)(mu-eta(5),eta(5)-C5H4-CR2-C5H4), where M = Mo or W and R = H or CH3, in the presence of triphenylphosphine or trimethylphosphine yields simple substitution derivatives M-2(CO)(5)L(mu-eta(5),eta(5)-C5H4-CR2-C5H4) or M-2(CO)(4)L-2(mu-eta(5),eta(5),-C5H4-CR2-C5H4). The compounds have been fully characterized by IR and NMR spectroscopy and elemental analysis. Phosphine ligands are found to occupy positions trans to the M-M bond. No evidence was found for disproportionation processes such as those found for similar reactions of the non-ring-coupled species. The molecular structures of two compounds have been determined: (mu-eta(5),eta(5)-C5H4-CH2-C5H4)Mo-2(CO)(5)(PPh3): monoclinic, P2(1)/c, a = 22.871(8), b = 16.415(6), c = 15.957(9) Angstrom, beta = 94.29(3)degrees, V = 5974(4) Angstrom(3), Z = 8, R(F)= 8.87%; (mu-eta(5),eta(5)-C5H4-CH2-C5H4)Mo-2(CO)(4)(PMe3)(2): monoclinic, P2(1)/c, a = 9.843(5), b = 15.343(7), c = 31.514(6) Angstrom, beta = 97.28(3)degrees, V = 4720(4) Angstrom(3), Z = 8, R(F) = 4.38%. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Idaho, Dept Chem, Moscow, ID 83844 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. Univ Delaware, Dept Chem & Biochem, Newark, DE 19716 USA. RP Bitterwolf, TE (reprint author), Univ Idaho, Dept Chem, Moscow, ID 83844 USA. EM bitterte@osprey.csrv.uidaho.edu NR 11 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-328X J9 J ORGANOMET CHEM JI J. Organomet. Chem. PD JUL 10 PY 1998 VL 562 IS 1 BP 89 EP 96 DI 10.1016/S0022-328X(98)00396-9 PG 8 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA ZZ645 UT WOS:000074751900012 ER PT J AU Lindsey, JW Jung, AE Narayanan, TK Ritchie, GD AF Lindsey, JW Jung, AE Narayanan, TK Ritchie, GD TI Acute effects of a bicyclophosphate neuroconvulsant on monoamine neurotransmitter and metabolite levels in the rat brain SO JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A LA English DT Article ID STRUCTURE-TOXICITY RELATIONSHIPS; ACID AB Naive male Sprague-Dawley rats were injected intraperitoneally (ip)with the bicyclophosphate convulsant trimethylolpropane phosphate (TMPP) at dose levels from 0.2 to 0.6 mg/kg. Rats were observed for convulsive activity, and were sacrificed 15 min posttreatment. Levels of the monoamine neurotransmitters norepinephrine (NE), epinephrine (EPI), dopamine (DA), and serotonin (5-HT) and the major metabolites 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) were assayed in iorebrain, midbrain, hindbrain, cerebellum and brainstem regions. Neurotransmitter and metabolite levels were compared between control rats and rats that did and did not experience seizures. TMPP administration induced significant decreases in levels of measured neurotransmitters that varied as a function of brain region, dose, and expression of the seizure activity. These results show that tonic or tonic-clonic seizures induced by TMPP administration (0.6 mg/kg) are reliably associated with regional decreases in serotonin, dopamine, and norepinephrine. Convulsive activity resulting from lower dose administrations (0.2-0.4 mg/kg) of TMPP result only in decreased regional levels of serotonin. C1 USN, Med Res Inst Detachment Toxicol, Wright Patterson AFB, OH 45433 USA. Geocenters Inc, Wright Patterson AFB, OH USA. RP Lindsey, JW (reprint author), USN, Med Res Inst Detachment Toxicol, 2612 5th St,Area B,Bldg 433, Wright Patterson AFB, OH 45433 USA. EM jlindsey@navy.al.wpaib.af.mil NR 24 TC 21 Z9 21 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0098-4108 J9 J TOXICOL ENV HEAL A JI J. TOXICOL. ENV. HEALTH PT A PD JUL 10 PY 1998 VL 54 IS 5 BP 421 EP 429 PG 9 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA ZV486 UT WOS:000074309400005 PM 9650574 ER PT J AU Weaver, BD Jackson, EM Summers, GP AF Weaver, BD Jackson, EM Summers, GP TI Effect of proton irradiation on the resistance in Tl2Ba2CaCu2O8 Josephson junctions and thin films SO PHYSICA C LA English DT Article ID TEMPERATURE; BEAM AB The effect of 2 MeV proton irradiation on the bulk onset transition temperature T-c, the bulk resistivity and the resistance of bicrystal Josephson junctions fabricated from Tl2Ca2BaCu2O8 is reported. Each of the measured parameters are found to vary nearly linearly with proton fluence. This is the first time a correlation between junction resistance and bulk T-c has been reported in the cuprate superconductors. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Landover, MD 20875 USA. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. RP Weaver, BD (reprint author), USN, Res Lab, Code 6615, Washington, DC 20375 USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JUL 10 PY 1998 VL 303 IS 1-2 BP 101 EP 107 DI 10.1016/S0921-4534(98)00252-4 PG 7 WC Physics, Applied SC Physics GA 106VV UT WOS:000075171900016 ER PT J AU Schrijver, CJ Title, AM Harvey, KL Sheeley, NR Wang, YM van den Oord, GHJ Shine, RA Tarbell, TD Hurlburt, NE AF Schrijver, CJ Title, AM Harvey, KL Sheeley, NR Wang, YM van den Oord, GHJ Shine, RA Tarbell, TD Hurlburt, NE TI Large-scale coronal heating by the small-scale magnetic field of the Sun SO NATURE LA English DT Article ID FLUX TRANSPORT; SOLAR CORONA; NETWORK AB Magnetic fields play a crucial role in heating the outer atmospheres of the Sun and Sun-like stars, but the mechanisms by which magnetic energy in the photosphere is converted to thermal energy in the corona remain unclear. Observations show that magnetic fields emerge onto the solar surface as bipolar regions with a broad range of length scales. On large scales, the bipolar regions survive for months before dispersing: diffusively(1-3). On the smaller scales, individual bipolar regions disappear within days but are continuously replenished by new small flux concentrations, resulting in a sustained state of mixed polarity(4). Here we determine the rate of emergence of these small bipolar regions and we argue that the frequent magnetic reconnections associated with these regions (an unavoidable consequence of continued flux replacement) will heat the solar atmosphere. The model that describes the details of these mixed-polarity regions(4) is complementary to the traditional diffusion model for large-scale flux dispersal(1-3), and a combination of the two should lead to a more complete understanding of the role of magnetic fields in stellar atmospheres. C1 Stanford Lockheed Inst Solar & Astrophys H1 12 25, Palo Alto, CA 94034 USA. Solar Phys Res Corp, Tucson, AZ 85718 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ Utrecht, Astron Inst, NL-3508 TA Utrecht, Netherlands. RP Schrijver, CJ (reprint author), Stanford Lockheed Inst Solar & Astrophys H1 12 25, 3251 Hanover St, Palo Alto, CA 94034 USA. NR 17 TC 132 Z9 133 U1 0 U2 5 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD JUL 9 PY 1998 VL 394 IS 6689 BP 152 EP 154 DI 10.1038/28108 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZZ203 UT WOS:000074705900044 ER PT J AU Gallagher, EL Elgar, S Thornton, EB AF Gallagher, EL Elgar, S Thornton, EB TI Megaripple migration in a natural surf zone SO NATURE LA English DT Article ID HUMMOCKY CROSS-STRATIFICATION; DIRECTIONALLY VARYING FLOWS; NEARSHORE; DUNES; ALIGNMENT AB Migrating megaripples are bedforms that appear in the surf zone of sandy coasts(1). With heights of 0.1 -0.5 m and wavelengths of 1-5m, they are similar in size and shape to small dunes, large ripples, or sand waves. Such sedimentary bedforms have been studied in subaerial(2), steady-flow(3) and intertidal(4) environments, as well as in laboratory flume experiments(5). They affect overlying currents by introducing hydraulic roughness(4,6), and may provide a mechanism for sediment transport(7,8) as well as forming sedimentary structures in preserved facies(9,10). The formation, orientation and migration of such bedforms is not understood well(11,12). Dunes, for example, can be aligned with their crests perpendicular to steady unidirectional winds(13), but in more complex wind fields their orientation becomes difficult to predict(14-17). Similarly, it is not known how sea-floor megaripples become aligned and migrate in the complex flows of the surf zone. Here we present observations in the surf zone of a natural beach which indicate that megaripples do not migrate in the direction of the vector sum of the currents, but are aligned so that the sediment transport normal to the bedform crest is maximized(17). This may need to be taken into account in modelling morphology change and interpreting existing and fossil morphologic patterns. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. Washington State Univ, Sch Elect Engn & Comp Sci, Pullman, WA 99164 USA. RP Gallagher, EL (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. EM egallagh@oc.nps.navy.mil; elgar@eecs.wsu.edu NR 28 TC 48 Z9 48 U1 1 U2 17 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD JUL 9 PY 1998 VL 394 IS 6689 BP 165 EP 168 DI 10.1038/28139 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZZ203 UT WOS:000074705900049 ER PT J AU Peiris, SM Pearson, TT Heinz, DL AF Peiris, SM Pearson, TT Heinz, DL TI Compression of klockmannite, CuSe SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CRYSTAL-STRUCTURE; PHASE-TRANSITION; COVELLITE; CALIBRATION; MBAR AB Copper selenide (CuSe) was compressed in a diamond anvil cell at room temperature up to a pressure of 52 GPa and studied using energy dispersive x-ray diffraction and Raman spectroscopy. CuSe is nearly isostructural with copper sulfide (CuS), and a previous study indicates that copper sulfide undergoes reversible pressure-induced amorphization at 18 GPa. The intensity of the x-ray diffraction peaks for CuSe decrease slowly, however, they never completely disappear up to a pressure of 52 GPa. The third-order Birch-Murnaghan equation of state fit to the data yields K-0 = 96.9 +/- 5.3 GPa and K-0' = 4.1 +/- 0.5. Vinet's universal equation of state yields essentially identical parameters. Raman spectroscopy demonstrates that upon compression, the S-S bond in CuS compresses differently than the Se-Se bond in CuSe, possibly accounting fur the different high pressure behavior of these two very similar compounds. (C) 1998 American Institute of Physics. C1 Univ Chicago, Dept Chem, Chicago, IL 60637 USA. Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA. Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA. Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. RP Peiris, SM (reprint author), USN, Res Lab, 6110, Washington, DC 20375 USA. NR 15 TC 3 Z9 3 U1 2 U2 22 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 JUL 8 PY 1998 VL 109 IS 2 BP 634 EP 636 DI 10.1063/1.476601 PG 3 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 108FM UT WOS:000075255400033 ER PT J AU Qiao, LX Wang, SM George, C Lewin, NE Blumberg, PM Kozikowski, AP AF Qiao, LX Wang, SM George, C Lewin, NE Blumberg, PM Kozikowski, AP TI Structure-based design of a new class of protein kinase C modulators SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TUMOR PROMOTERS; PHORBOL ESTERS; STEREOCHEMISTRY; TELEOCIDINS; MODEL C1 Georgetown Univ, Med Ctr, Drug Discovery Program, Washington, DC 20007 USA. USN, Res Lab, Washington, DC 20375 USA. NCI, Mol Mechanisms Tumor Promot Sect, Cellular Carcinogenesis & Tumor Promot Lab, Bethesda, MD 20892 USA. RP Kozikowski, AP (reprint author), Georgetown Univ, Med Ctr, Drug Discovery Program, Washington, DC 20007 USA. RI Wang, Shaomeng/E-9686-2010 NR 16 TC 28 Z9 29 U1 0 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 JUL 8 PY 1998 VL 120 IS 26 BP 6629 EP 6630 DI 10.1021/ja980513u PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA ZZ420 UT WOS:000074727600036 ER PT J AU Chen, LG Sun, FR Wu, C AF Chen, LG Sun, FR Wu, C TI Performance of chemical engines with a mass leak SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID FINITE-TIME; THERMODYNAMICS; MODEL AB The performance of an isothermal chemical engine with finite-rate mass transfer and a mass leak is analysed in this paper. The relations between the optimal power output and the efficiency, the maximum power output and the corresponding efficiency and the maximum efficiency and the corresponding power output are derived on the ba!;is of linear (Onsager) mass-transfer law using the analogous method of finite-time thermodynamics for a heat engine. There exists a maximum efficiency bound with nonzero power output besides the maximum power output bound with nonzero efficiency for the engine. This characteristic is different from that for the chemical engine with the sole irreversibility of finite-rate mass transfer. The optimal region of parameter selection for the engine is provided and the effect of the mass-transfer law is analysed. C1 Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Chen, LG (reprint author), Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. NR 27 TC 34 Z9 43 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD JUL 7 PY 1998 VL 31 IS 13 BP 1595 EP 1600 DI 10.1088/0022-3727/31/13/014 PG 6 WC Physics, Applied SC Physics GA ZZ902 UT WOS:000074780900014 ER PT J AU Glembocki, OJ Tuchman, JA Dagata, JA Ko, KK Pang, SW Stutz, CE AF Glembocki, OJ Tuchman, JA Dagata, JA Ko, KK Pang, SW Stutz, CE TI Electronic properties of GaAs surfaces etched in an electron cyclotron resonance source and chemically passivated using P2S5 SO APPLIED PHYSICS LETTERS LA English DT Article ID SEMICONDUCTOR SURFACES; FERMI-LEVEL; N-TYPE; PHOTOREFLECTANCE; DAMAGE AB Photoreflectance has been used to study the electronic properties of (100) GaAs surfaces exposed to a Cl-2/Ar plasma generated by an electron cyclotron resonance source and subsequently passivated by P2S5. The plasma etch shifts the Fermi level of p-GaAs from near the valence band to midgap. but has no effect on n-GaAs. For ion energies below 250 eV, post-etch P2S5 chemical passivation removes the surface etch damage and restores the electronic properties to pre-etch conditions. Above 250 eV, the etch produces subsurface defects which cannot be chemically passivated. Auger electron spectroscopy shows that etching increases As at the GaAs/oxide interface, while passivation reduces it. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Washington, DC 20375 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Wright Patterson Labs, Wright Patterson AFB, OH 45433 USA. US Dept Commerce, Div Precis Engn, Mfg Engn Lab, Div Technol, Washington, DC 20230 USA. RP Glembocki, OJ (reprint author), Optex Corp, Gaithersburg, MD 20899 USA. RI Pang, Stella/A-7770-2012 OI Pang, Stella/0000-0002-4330-0877 NR 17 TC 7 Z9 7 U1 0 U2 0 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 JUL 6 PY 1998 VL 73 IS 1 BP 114 EP 116 DI 10.1063/1.121785 PG 3 WC Physics, Applied SC Physics GA 108PT UT WOS:000075275200039 ER PT J AU Garland, NL AF Garland, NL TI Temperature dependence of the reaction: SO+O-2 SO CHEMICAL PHYSICS LETTERS LA English DT Article ID RATE COEFFICIENTS; O-2; MECHANISM AB The temperature dependence of the rate constant of the reaction SO + O-2 was measured over the range of 450-585 K at 20 Ton total pressure. SO radicals were generated by photolysis of DMSO at 222 nm and detected by laser-induced fluorescence. The measured rate constants were combined with data obtained from the literature to obtain an Arrhenius expression k(T)=(2.2 +/- 0.5) x 10(-13)exp[-(2340 +/- 90)/T] cm(3) s(-1) over the temperature range of 250-585 K and k(T) = 1.5 x 10(-17)T(1.4)exp[- 1868/T] cm(3) s(-1) over the range of 250-3500 K. (C) 1998 Published by 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 6111, Washington, DC 20375 USA. EM nancy.garland@nrl.navy.mil NR 21 TC 5 Z9 5 U1 0 U2 3 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 JUL 3 PY 1998 VL 290 IS 4-6 BP 385 EP 390 DI 10.1016/S0009-2614(98)00553-3 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZZ294 UT WOS:000074715000014 ER PT J AU White, CT Mintmire, JW AF White, CT Mintmire, JW TI Density of states reflects diameter in nanotubes SO NATURE LA English DT Letter ID TUBULES C1 USN, Res Lab, Washington, DC 20375 USA. RP White, CT (reprint author), USN, Res Lab, Code 6179, Washington, DC 20375 USA. OI Mintmire, John/0000-0002-6551-0349 NR 9 TC 133 Z9 136 U1 3 U2 16 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD JUL 2 PY 1998 VL 394 IS 6688 BP 29 EP 30 DI 10.1038/27801 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZY030 UT WOS:000074579600031 ER PT J AU Bell, RE Blankenship, DD Finn, CA Morse, DL Scambos, TA Brozena, JM Hodge, SM AF Bell, RE Blankenship, DD Finn, CA Morse, DL Scambos, TA Brozena, JM Hodge, SM TI Influence of subglacial geology on the onset of a West Antarctic ice stream from aerogeophysical observations SO NATURE LA English DT Article ID SHEET; OSCILLATIONS AB Marine ice-sheet collapse can contribute to rapid sea-level rise(1) Today, the West Antarctic Ice Sheet contains an amount of ice equivalent to approximately six metres of sea-level rise, but most of the ice is in the slowly moving interior reservoir. A relatively small fraction of the ice sheet comprises several rapidly flowing ice streams which drain the ice to the sea. The evolution of this drainage system almost certainly governs the process of ice-sheet collapse(2-5). The thick and slow-moving interior ice reservoir is generally fixed to the underlying bedrock while the ice streams glide over lubricated beds at velocities of up to several hundred metres per year. The source of the basal lubricant-a water-saturated till(6,7) overlain by a water systems(8)-may be linked to the underlying geology. The West Antarctic Ice Sheet rests over a geologically complex region characterized by thin crust, high heat flows, active volcanism and sedimentary basins(9-16). Here we use aerogeophysical measurements to constrain the geological setting of the onset of an active West Antarctic ice stream. The onset coincides with a sediment-filled basin incised by a steep-sided valley. This observation supports the suggestion(5,17) that ice-stream dynamics-and therefore the response of the West Antarctice Ice Sheet to changes in climate-are strongly modulated by the underlying geology. C1 Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY 10964 USA. Univ Texas, Inst Geophys, Austin, TX 78759 USA. US Geol Survey, Denver, CO 80225 USA. Natl Snow & Ice Data Ctr, Boulder, CO 80309 USA. USN, Res Lab, Washington, DC 20375 USA. US Geol Survey, Tacoma, WA 98406 USA. RP Bell, RE (reprint author), Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY 10964 USA. EM robinb@ldeo.columbia.edu RI Scambos, Ted/B-1856-2009; Blankenship, Donald/G-5935-2010 NR 27 TC 123 Z9 123 U1 1 U2 8 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD JUL 2 PY 1998 VL 394 IS 6688 BP 58 EP 62 DI 10.1038/27883 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZY030 UT WOS:000074579600046 ER PT J AU Rath, BB van Keuren, D AF Rath, BB van Keuren, D TI The Naval Research Laboratory - 75 years of innovations SO ADVANCED MATERIALS & PROCESSES LA English DT Article C1 USN, Res Lab, Washington, DC 20375 USA. RP Rath, BB (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 JUL PY 1998 VL 154 IS 1 BP 79 EP 82 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA ZY058 UT WOS:000074582400010 ER PT J AU Merzbacher, CI Barker, JG Swider, KE Rolison, DR AF Merzbacher, CI Barker, JG Swider, KE Rolison, DR TI Structure of Ru-Ti oxide aerogels: a SANS study SO ADVANCES IN COLLOID AND INTERFACE SCIENCE LA English DT Article; Proceedings Paper CT TRI/Princeton Workshop on Characterization of Porous Materials - From Angstroms to Millimeters CY JUN 18-20, 1997 CL PRINCETON, NJ DE aerogel; SANS; contrast matching; ruthenium-titanium oxide; nanoscale structure ID ANGLE NEUTRON-SCATTERING; MORPHOLOGY AB Small-angle neutron scattering (SANS) has been used to characterize Ru-Ti oxide aerogels annealed under various atmospheres and temperatures. The pores were filled with H(2)O/D(2)O solutions that match the scattering properties of either RuO(2) or TiO(2), therefore scattering from the remaining unmatched phase is measured independently. The structure of the RuO(2), and TiO(2), components of the aerogel detected by SANS depends more on annealing temperature than annealing atmosphere. The results are consistent with a branched, polymeric network made up of 8-16 nm TiO(2), particles and < 5-nm RuO(2), particles. The SANS results are supported by TEM. This study demonstrates that contrast-matching SANS is complementary to other techniques for characterizing the structure of two-phase aerogels. Published by Elsevier Science B.V. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Merzbacher, CI (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. EM merzbacher@nrl.navy.mil NR 21 TC 8 Z9 8 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0001-8686 J9 ADV COLLOID INTERFAC JI Adv. Colloid Interface Sci. PD JUL PY 1998 VL 76 BP 57 EP 69 DI 10.1016/S0001-8686(98)00041-4 PG 13 WC Chemistry, Physical SC Chemistry GA ZZ293 UT WOS:000074714900005 ER PT J AU Minniti, RJ Mueller, TJ AF Minniti, RJ Mueller, TJ TI Experimental investigation of unsteady aerodynamics and aeroacoustics of a thin airfoil SO AIAA JOURNAL LA English DT Article AB An experimental investigation of the unsteady problem for a thin, symmetric airfoil exposed to periodic gusting was performed in a free-jet anechoic wind-tunnel facility. The gusting events were created upstream such that there was a small longitudinal, i.e., spanwise, wave number and the gust could be approximated as two dimensional. Measurements of the unsteady velocity field, the unsteady pressure at the airfoil surface, and the acoustic field were made for two values of axial and normal reduced frequency. The unsteady pressure distribution along the airfoil was computed using the Sears method and unsteady velocity data, In addition, the pressure distribution was computed using acoustic data as input to a numerical inversion technique. The results of each technique were compared with the experimentally obtained unsteady pressure distribution. The inversion technique showed good agreement with the Sears method. However, comparison with experimental results illustrated that the theoretical estimates, although exhibiting trends similar to the experimental data, consistently underestimated the experimental unsteady pressure distribution at the lower reduced frequency, indicating the presence of viscous affects. Better agreement between experimental and theoretical results was obtained at the higher reduced frequency where viscous effects were less prominent. C1 Univ Notre Dame, Dept Aerosp & Mech Engn, Notre Dame, IN 46556 USA. RP Minniti, RJ (reprint author), USN, Ctr Surface Warfare, Carderock Div, 9500 MacArthur Blvd, W Bethesda, MD 20817 USA. NR 14 TC 6 Z9 6 U1 1 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 JUL PY 1998 VL 36 IS 7 BP 1149 EP 1156 DI 10.2514/2.525 PG 8 WC Engineering, Aerospace SC Engineering GA 147VB UT WOS:000077516900004 ER PT J AU Jones, KD Dohring, CM Platzer, MF AF Jones, KD Dohring, CM Platzer, MF TI Experimental and computational investigation of the Knoller-Betz effect SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 34th Aerospace Sciences Meeting and Exhibit CY JAN 15-19, 1996 CL RENO, NEVADA SP Amer Inst Aeronaut & Astronaut ID AIRFOIL; PROPULSION; MOTION; POWER; WAKE AB The ability of a sinusoidally plunging airfoil to produce thrust, known as the Knoller-Betz or Katzmayr effect, is investigated experimentally and numerically. Water-tunnel experiments are performed providing flow visualization and laser Doppler velocimetry data of the unsteady wakes formed by the plunging foils. Vortical structures and time-averaged velocity profiles in the wake are compared with numerical computations from a previously developed inviscid, unsteady panel code that utilizes a nonlinear wake model. Qualitative and quantitative comparisons are excellent over a broad range of reduced frequencies and Strouhal numbers, indicating that the formation and evolution of the thrust-indicative wake structures are primarily inviscid phenomena. Results at Strouhal numbers greater than about 1.0 (based on plunge amplitude) demonstrate nonsymmetric, deflected wake patterns, where both an average thrust and an average lift are produced. These highly nonlinear wake formations are generated reproducibly, both experimentally and numerically. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Jones, KD (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. NR 39 TC 144 Z9 151 U1 2 U2 13 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 JUL PY 1998 VL 36 IS 7 BP 1240 EP 1246 DI 10.2514/2.505 PG 7 WC Engineering, Aerospace SC Engineering GA 147VB UT WOS:000077516900015 ER PT J AU Cipolla, KM Liakopoulos, A Rockwell, DO AF Cipolla, KM Liakopoulos, A Rockwell, DO TI Quantitative imaging in proper orthogonal decomposition of flow past a delta wing SO AIAA JOURNAL LA English DT Article ID COHERENT STRUCTURES; VORTEX BREAKDOWN; VELOCIMETRY; TURBULENCE; CHANNEL AB Snapshot proper orthogonal decomposition is used to characterize the unsteady flow past a delta wing, focusing on the structure of the leading-edge vortices. The decomposition is applied to two-dimensional velocity fields obtained via a laser-scanning version of high-image-density particle image velocimetry to extract the most coherent structures in the flow. Data are analyzed for cases involving both a stationary wing and a wing undergoing harmonic oscillations in roll. In each case, the velocity fields are reconstructed as a truncated series expansion in terms of the computed eigenfunctions from which the corresponding contours of constant vorticity and sectional streamline patterns are calculated. Comparison with the original data demonstrates that the analysis provides an accurate representation of the velocity fields while eliminating extraneous small-scale features. Inclusion of as few as two eigenfunctions in the reconstruction series reproduces the largest-scale features of the leading-edge vortices, whereas the inclusion of half of the total number of eigenfunctions produces a reconstructed field that captures the majority of the Bow features. By appropriately combining the spatial and temporal components of the proper orthogonal decomposition analysis, one obtains the dynamical structures that evolve in both space and time, such as the fluctuations in the location of vortex breakdown. C1 Lehigh Univ, Dept Mech Engn & Mech, Packard Lab 354, Bethlehem, PA 18015 USA. RP Cipolla, KM (reprint author), USN, Undersea Warfare Ctr, Submarine Sonar Dept, Towed & Deployed Sensors Div, Code 2141,1176 Howell St, Newport, RI 02841 USA. NR 26 TC 9 Z9 9 U1 0 U2 1 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 JUL PY 1998 VL 36 IS 7 BP 1247 EP 1255 DI 10.2514/2.506 PG 9 WC Engineering, Aerospace SC Engineering GA 147VB UT WOS:000077516900016 ER PT J AU Morrow, RC Morrow, AL Haislip, G AF Morrow, RC Morrow, AL Haislip, G TI Methylphenidate in the United States, 1990 through 1995 SO AMERICAN JOURNAL OF PUBLIC HEALTH LA English DT Article ID DISORDER C1 Eastern Virginia Med Sch, Ctr Pediat Res, Norfolk, VA 23501 USA. USN, Ctr Environm Hlth, Norfolk, VA USA. Drug Enforcement Adm, Washington, DC USA. RP Morrow, RC (reprint author), Eastern Virginia Med Sch, Ctr Pediat Res, 885 Brambleton, Norfolk, VA 23501 USA. NR 4 TC 16 Z9 16 U1 0 U2 0 PU AMER PUBLIC HEALTH ASSOC INC PI WASHINGTON PA 1015 FIFTEENTH ST NW, WASHINGTON, DC 20005 USA SN 0090-0036 J9 AM J PUBLIC HEALTH JI Am. J. Public Health PD JUL PY 1998 VL 88 IS 7 BP 1121 EP 1121 DI 10.2105/AJPH.88.7.1121 PG 1 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA ZY340 UT WOS:000074610600029 PM 9663168 ER PT J AU Snail, KA Hanssen, LM AF Snail, KA Hanssen, LM TI Magnification of conic mirror reflectometers SO APPLIED OPTICS LA English DT Article AB Conic mirror reflectometers are used to measure the diffuse reflectance and total integrated scatter of surfaces. In spite of the long history of using conic mirrors for these purposes, the maximum magnification of the three primary types of conic mirror (hemisphere, hemiellipsoid, and dual paraboloid) had not been compared quantitatively. To our knowledge, an exact magnification formula has not been published for any of the three primary conic mirrors. The maximum magnification is needed for proper sizing of detectors and radiation sources used with reflectometers. Exact analytical expressions for the maximum magnification of a Coblentz hemisphere, a hemiellipsoid, and a dual-paraboloid mirror system are derived and compared. C1 USN, Res Lab, Washington, DC 20375 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Snail, KA (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 22 TC 6 Z9 6 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 JUL 1 PY 1998 VL 37 IS 19 BP 4143 EP 4149 DI 10.1364/AO.37.004143 PG 7 WC Optics SC Optics GA ZW479 UT WOS:000074415100013 PM 18285854 ER PT J AU Mintmire, JW White, CT AF Mintmire, JW White, CT TI First-principles band structures of armchair nanotubes SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article ID NANOSCALE GRAPHITIC TUBULES; CARBON NANOTUBES; ELECTRONIC-STRUCTURE; GRAPHENE TUBULES; POLYACETYLENE; MICROTUBULES AB Recent work by Thess et al. suggests that (10,10) carbon nanotubes with diameters of 1.38 nm have been observed with high conductivities. Other experimental results have directly measured the density of states of single-wall carbon nanotubes with diameters in the range 1-1.5nm. Herein we examine the expected electronic properties of armchair single-wall nanotubes with diameters in this range, and present first-principles local-density functional results for band structure and density of states of these SWNTs. We find our results support the validity of the simple graphene sheet model, and are in close agreement with experimental measurements of the density of states of these materials. 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 29 TC 36 Z9 36 U1 0 U2 5 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD JUL PY 1998 VL 67 IS 1 BP 65 EP 69 DI 10.1007/s003390050738 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA ZZ424 UT WOS:000074728000008 ER PT J AU Pitman, KT Johnson, JT Edington, H Barnes, L Day, R Wagner, RL Myers, EN AF Pitman, KT Johnson, JT Edington, H Barnes, L Day, R Wagner, RL Myers, EN TI Lymphatic mapping with isosulfan blue dye in squamous cell carcinoma of the head and neck SO ARCHIVES OF OTOLARYNGOLOGY-HEAD & NECK SURGERY LA English DT Article; Proceedings Paper CT 39th Annual Meeting of the American-Society-for-Head-and-Neck-Surgery CY MAY 11-13, 1997 CL SCOTTSDALE, ARIZONA SP Amer Soc Head & Neck Surg ID SENTINEL NODE BIOPSY; EARLY-STAGE MELANOMA; LYMPHADENECTOMY; CANCER AB Objective: To determine whether intraoperative lymphatic mapping with isosulfan blue dye and sentinel lymph node biopsy accurately demonstrates the pathway of regional metastases from mucosal. sites in squamous cell carcinoma of the head and neck. Design: A prospective clinical study of intraoperative lymphatic mapping. Setting: An academic tertiary referral center. Patients: Patients with previously untreated squamous cell carcinoma of the head and neck whose surgical treatment included neck dissection. Intervention: Injection of isosulfan blue dye into the mucosa surrounding squamous cell carcinomas of the upper aerodigestive tract during cervical lymphadenectomy. Outcome Measures: Correlation of the pathologic findings in the blue sentinel lymph node with those in the remaining cervical lymphatics. Results: No blue-stained cervical lymphatics were identified after injection of the mucosa surrounding the primary squamous cell carcinoma with isosulfan dye. Conclusion: The technique of intraoperative lymphatic mapping with isosulfan blue dye requires further study before it can be used for the detection of occult cervical metastases in squamous cell carcinoma of the head and neck. C1 Univ Pittsburgh, Sch Med, Dept Otolaryngol, Pittsburgh, PA 15213 USA. Univ Pittsburgh, Sch Med, Dept Plast Surg, Pittsburgh, PA 15213 USA. Univ Pittsburgh, Sch Med, Dept Pathol, Pittsburgh, PA 15213 USA. Univ Pittsburgh, Inst Canc, Dept Biostat, Pittsburgh, PA USA. RP Pitman, KT (reprint author), USN, Med Ctr, Dept Otolaryngol, Code 0609, Portsmouth, VA 23708 USA. NR 10 TC 71 Z9 77 U1 0 U2 0 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0886-4470 J9 ARCH OTOLARYNGOL JI Arch. Otolaryngol. Head Neck Surg. PD JUL PY 1998 VL 124 IS 7 BP 790 EP 793 PG 4 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA ZZ942 UT WOS:000074784900010 PM 9677115 ER PT J AU Balick, B Alexander, J Hajian, AR Terzian, Y Perinotto, M Patriarchi, P AF Balick, B Alexander, J Hajian, AR Terzian, Y Perinotto, M Patriarchi, P TI Fliers and other microstructures in planetary nebulae. IV. Images of elliptical PNs from the Hubble Space Telescope SO ASTRONOMICAL JOURNAL LA English DT Article DE planetary nebulae : general; planetary nebulae : individual (NGC 3242, NGC 6826, NGC 7009, NGC 7662); stars : mass loss ID CENTRAL STARS; RADIATION GASDYNAMICS; DYNAMICAL EVOLUTION; FAST WINDS; MASS; NGC-7009; IONIZATION; NGC-7662; NGC-6543; REGIONS AB We report new results from high spatial resolution Wide Field Planetary Camera 2 imaging studies of "FLIERs" and other microstructures in the planetary nebulae NGC 3242, 6826, 7009, and 7662. Most FLIERs have head-tail morphologies, with the tails pointing outward from the nucleus. Ionization gradients that decrease with distance from the nebular center are ubiquitous. These are consistent with an ionization front in neutral knots of density approximate to 10(4) cm(-3). Can neutral knots account for the properties of FLIERs? We compare two broad classes of possible explanations for FLIERs with the new images: high-speed bullets ramming through the shells of planetary nebulae, and photoevaporated gas swept by winds into head-tail shapes. Both classes of models fail basic consistency tests. Hence an entirely new conceptual paradigm is needed to account for the phenomenology of FLIERs. C1 Univ Washington, Dept Astron, Seattle, WA 98195 USA. USN Observ, Washington, DC 20392 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Cornell Univ, Natl Astron & Ionosphere Ctr, Ithaca, NY 14853 USA. Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. CNR, Ctr Astron Infrarossa & Studio Mezzo Interstellar, I-50125 Florence, Italy. RP Balick, B (reprint author), Univ Washington, Dept Astron, Box 351580, Seattle, WA 98195 USA. EM balick@astro.washington.edu; jalex@u.washington.edu; hajian@fornax.usno.navy.mil; terzian@astrosun.tn.cornell.edu; mariop@arcetri.astro.it; patriarchi@arcetri.astro.it NR 51 TC 97 Z9 97 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 JUL PY 1998 VL 116 IS 1 BP 360 EP 371 DI 10.1086/300429 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 104KB UT WOS:000075012500032 ER PT J AU Ma, C Arias, EF Eubanks, TM Fey, AL Gontier, AM Jacobs, CS Sovers, OJ Archinal, BA Charlot, P AF Ma, C Arias, EF Eubanks, TM Fey, AL Gontier, AM Jacobs, CS Sovers, OJ Archinal, BA Charlot, P TI The International Celestial Reference Frame as realized by very long baseline interferometry SO ASTRONOMICAL JOURNAL LA English DT Article DE astrometry; catalogs; quasars : general; radio continuum; reference systems; techniques : interferometric ID RADIO REFERENCE FRAME; LINE INTERFEROMETRY; SYSTEM; EARTH; PRECESSION; GRADIENTS; NUTATION; GEODESY; DELAY; VLBI AB A quasi-inertial reference frame is defined based on the radio positions of 212 extragalactic sources distributed over the entire sky. The positional accuracy of these sources is better than about 1 mas in both coordinates. The radio positions are based upon a general solution for all applicable dual-frequency 2.3 and 8.4 GHz Mark III very long baseline interferometry data available through the middle of 1995, consisting of 1.6 million pairs of group delay and phase delay rate observations. Positions and details are also given for an additional 396 objects that either need further observation or are currently unsuitable for the definition of a high-accuracy reference frame. The final orientation of the frame axes has been obtained by a rotation of the positions into the system of the International Celestial Reference System and is consistent with the FK5 J2000.0 optical system, within the limits of the link accuracy. The resulting International Celestial Reference Frame has been adopted by the International Astronomical Union as the fundamental celestial reference frame, replacing the FK5 optical frame as of 1998 January 1. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Observ Astron La Plata, RA-1900 La Plata, Argentina. Observ Naval Buenos Aires, Buenos Aires, DF, Argentina. USN Observ, Washington, DC 20392 USA. Observ Paris, CNRS, URA 1125, F-75014 Paris, France. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Ma, C (reprint author), NASA, Goddard Space Flight Ctr, Code 926, Greenbelt, MD 20771 USA. RI Ma, Chopo/D-4751-2012; OI Eubanks, Thomas Marshall/0000-0001-9543-0414 NR 42 TC 442 Z9 449 U1 2 U2 6 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 JUL PY 1998 VL 116 IS 1 BP 516 EP 546 DI 10.1086/300408 PG 31 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 104KB UT WOS:000075012500048 ER PT J AU Bottcher, M Dermer, CD AF Bottcher, M Dermer, CD TI On Compton scattering scenarios for blazar flares SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : jets; radiation mechanisms : nonthermal ID ACTIVE GALACTIC NUCLEI; GAMMA-RAYS; EMISSION; MARKARIAN-421; MODEL; JET AB The synchrotron reflection scenario recently proposed to explain gamma-ray flares observed from blazar jets is studied. Our analysis takes into account the angular distribution of the beamed radiation, the finite extent of the scattering region, and light-travel-time effects. We compare energy densities and powers for synchrotron, synchrotron self-Compton, reflected synchrotron (RSy), and external Compton scattering processes. If the width of the scattering layer is much larger than Gamma R-B', where Gamma and R-B' denote the bulk Lorentz factor and the comoving frame radius of the plasma blob, respectively, then the ratio of the RSy and synchrotron energy densities is similar to 4 Gamma(3)n(BLR)sigma(T)R(B)' where n(BLR) is the mean particle density in the broad line region (BLR). Our results imply that Thomson-thick scattering regions of narrow extent must be present for the synchrotron reflection mechanism to operate effectively. This process seems unlikely to cause flares in lineless BL Lac sources, where X-ray and TeV flares are common and the BLR is thought to be weak or absent. We sketch time profiles of flares for Various scenarios. C1 Rice Univ, Dept Space Phys & Astron, Houston, TX 77005 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Bottcher, M (reprint author), Rice Univ, Dept Space Phys & Astron, 6100 Main St, Houston, TX 77005 USA. NR 34 TC 33 Z9 33 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUL 1 PY 1998 VL 501 IS 1 BP L51 EP L54 DI 10.1086/311458 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZZ948 UT WOS:000074785500012 ER PT J AU Wang, YM AF Wang, YM TI Network activity and the evaporative formation of polar plumes SO ASTROPHYSICAL JOURNAL LA English DT Article DE solar wind; Sun : chromosphere; Sun : corona; Sun : magnetic fields; Sun : UV radiation; Sun : X-rays, gamma rays ID TELESCOPE; PLASMA AB It has previously been suggested that polar plumes are generated and maintained by strong, localized heating within coronal holes and that this heating is somehow associated with the interaction between small magnetic bipoles and nearby unipolar flux concentrations. These ideas are used here as the basis of a model for the formation and evolution of coronal plumes. The energy deposition rate in a plume is taken to be proportional to the rate at which magnetic flux becomes reconnected to the nearby monopole as the poles of the bipole are separated by the supergranular flow field. The heat input is conducted down to the base of the newly opened flux tube (located at the majority-polarity end of the bipole), where a small fraction of the energy goes into lifting chromospheric gas into the corona, while the rest is radiated away. The evaporation timescale (tau(evap) similar to 6 hr) represents the characteristic time for a new plume to form following the emergence of a bipole. Once flux exchange between the bipole and the unipolar flux concentration ceases, the plume decays on the radiative cooling timescale tau(cool) similar to 4 hr. In the absence of new bipole eruptions, the total lifetime of a plume is found to be 12-24 hr. The model accounts for the quiescent nature of polar plumes and the tendency for the diffuse plume emission to strengthen as the underlying bright network features disperse and decay. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 18 TC 53 Z9 53 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 JUL 1 PY 1998 VL 501 IS 1 BP L145 EP L150 DI 10.1086/311445 PN 2 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZZ948 UT WOS:000074785500030 ER PT J AU Ball, R Auker, CR Ford, GC Lawrence, D AF Ball, R Auker, CR Ford, GC Lawrence, D TI Decompression sickness presenting as forearm swelling and peripheral neuropathy: A case report SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article AB Neurological symptoms after decompression from a dive are usually thought to be manifestations of central nervous system (CNS) decompression sickness (DCS). We present a case of DCS in which neurological symptoms are present but which the clinical findings, magnetic resonance imaging and electroneuromyographic studies suggest were caused by muscle injury and exacerbation of an existing peripheral neuropathy. This finding supports the alternative hypothesis that some neurological symptoms and signs in DCS are due to effects on peripheral nerves rather than the CNS. C1 USN, Med Res Inst, Bethesda, MD 20889 USA. Uniformed Serv Univ Hlth Sci, Bethesda, MD 20814 USA. Natl Naval Med Ctr, Bethesda, MD 20889 USA. RP Ball, R (reprint author), USN, Med Res Inst, Code 54,8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 8 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 JUL PY 1998 VL 69 IS 7 BP 690 EP 692 PG 3 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA ZZ731 UT WOS:000074761500012 PM 9681377 ER PT J AU Rogers, DP Dorman, CE Edwards, KA Brooks, IM Melville, WK Burk, SD Thompson, WT Holt, T Strom, LM Tjernstrom, M Grisogono, B Bane, JM Nuss, WA Morley, BM Schanot, AJ AF Rogers, DP Dorman, CE Edwards, KA Brooks, IM Melville, WK Burk, SD Thompson, WT Holt, T Strom, LM Tjernstrom, M Grisogono, B Bane, JM Nuss, WA Morley, BM Schanot, AJ TI Highlights of Coastal Waves 1996 SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID ATMOSPHERIC BOUNDARY-LAYER; THERMAL MESOSCALE CIRCULATIONS; OCEAN DYNAMICS EXPERIMENT; TURBULENCE CLOSURE-MODEL; TRAPPED WIND REVERSALS; STATES WEST-COAST; NORTHERN CALIFORNIA; UNITED-STATES; MARINE LAYER; BALTIC COAST AB Some of the highlights of an experiment designed to study coastal atmospheric phenomena along the California coast (Coastal Waves 1996 experiment) are described. This study was designed to address several problems, including the cross-shore variability and turbulent structure of the marine boundary layer, the influence of the coast on the development of the marine layer and clouds, the ageostrophy of the flow, the dynamics of trapped events, the parameterization of surface fluxes, and the supercriticality of the marine layer. Based in Monterey, California, the National Center for Atmospheric Research (NCAR) C-130 Hercules and the University of North Carolina Piper Seneca obtained a comprehensive set of measurements on the structure of the marine layer. The study focused on the effects of prominent topographic features on the wind. Downstream of capes and points, narrow bands of high winds are frequently encountered. The NCAR-designed Scanning Aerosol Backscatter Lidar (SABL) provided a unique opportunity to connect changes in the depth of the boundary layer with specific features in the dynamics of the flow field. An integral part of the experiment was the use of numerical models as forecast and diagnostic tools. The Naval Research Laboratory's Coupled Ocean Atmosphere Model System (COAMPS) provided high-resolution forecasts of the wind field in the vicinity of capes and points, which aided the deployment of the aircraft. Subsequently, this model and the MIUU (University of Uppsala) numerical model were used to support the analysis of the field data. These are some of the most comprehensive measurements of the topographically forced marine layer that have been collected. SABL proved to be an exceptionally useful tool to resolve the small-scale structure of the boundary layer and, combined with in situ turbulence measurements, provides new insight into the structure of the marine atmosphere. Measurements were made sufficiently far offshore to distinguish between the coastal and open ocean effects. COAMPS proved to be an excellent forecast tool and both it and the MIUU model are integral parts of the ongoing analysis. The results highlight the large spatial variability that occurs directly in response to topographic effects. Routine measurements are insufficient to resolve this variability. Numerical weather prediction model boundary conditions cannot properly define the forecast system and often underestimate the wind speed and surface wave conditions in the nearshore region. This study was a collaborative effort between the National Science Foundation, the Office of Naval Research, the Naval Research Laboratory, and the National Oceanographic and Atmospheric Administration. C1 Univ Calif San Diego, Scripps Inst Oceanog, Phys Oceanog Res Div, La Jolla, CA 92093 USA. USN, Res Lab, Monterey, CA USA. Uppsala Univ, Dept Meteorol, Uppsala, Sweden. Univ N Carolina, Chapel Hill, NC USA. USN, Postgrad Sch, Monterey, CA USA. Natl Ctr Atmospher Res, Res Aviat Facil, Boulder, CO USA. RP Rogers, DP (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Phys Oceanog Res Div, La Jolla, CA 92093 USA. RI Brooks, Ian/E-1378-2012; OI Brooks, Ian/0000-0002-5051-1322; Tjernstrom, Michael/0000-0002-6908-7410 NR 43 TC 70 Z9 70 U1 0 U2 2 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 JUL PY 1998 VL 79 IS 7 BP 1307 EP 1326 DI 10.1175/1520-0477(1998)079<1307:HOCW>2.0.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 101XC UT WOS:000074892600001 ER PT J AU Moran, JM Smith, DR Snow, JT AF Moran, JM Smith, DR Snow, JT TI Report on the Fourth International Conference on School and Popular Meteorological and Oceanographic Education SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB The Fourth International Conference on School and Popular Meteorological and Oceanographic Education was held 22-26 July 1996 in Edinburgh, Scotland. Conference attendees included 125 educators, meteorologists, oceanographers, and government officials representing 19 nations. The themes of the conference were the roles of meteorology and oceanography in science education and the benefits derived from improved environmental awareness and scientific literacy, particularly weather awareness, meteorological literacy, and understanding of the ocean. Formal presentations, workshops, poster sessions, and demonstrations provided information on programs for teacher enhancement, computer-aided instruction, and classroom access to real-time weather information through the World Wide Web. C1 USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. Univ Wisconsin, Green Bay, WI 54302 USA. Univ Oklahoma, Coll Geosci, Norman, OK 73019 USA. RP Smith, DR (reprint author), USN Acad, Dept Oceanog, 572 Holloway Rd, Annapolis, MD 21402 USA. NR 6 TC 0 Z9 0 U1 0 U2 2 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 JUL PY 1998 VL 79 IS 7 BP 1387 EP 1395 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 101XC UT WOS:000074892600008 ER PT J AU Singh, A Schoen, PE Guedeau-Boudeville, MA AF Singh, A Schoen, PE Guedeau-Boudeville, MA TI Temperature dependent membrane phase reorganization in giant vesicles SO CHEMISTRY AND PHYSICS OF LIPIDS LA English DT Article DE giant vesicles; diacetylene; phospholipid; tubule; optical microscopy ID SYSTEMS; TUBULES AB Giant unilamellar vesicles (GUV) from diacetylenic phospholipid, 1,2 bis(heptacosa-8,10-diynoyl)-sn-glycero-3-phosphocholine (DC6.15PC), have been prepared by applying electric field to the aqueous dispersion maintained above its chain melting transition temperature (T-m) of 58.9 degrees C. Previous studies have shown that large vesicles (similar to 1 mu m or greater diameter) of the diacetylenic lipid transform into the tubule morphology when the temperature of the dispersion medium is dropped below its T-m but these giant vesicles (200 mu m diameter) are stable far below T-m. Then within a 2 degrees temperature range at about 32 degrees C (26 degrees below T-m) the giant vesicles suddenly collapse, leaving oddly branched structures. Giant vesicles formed from the saturated lipid 1,2 distearoyl phosphatidylcholine, by contrast, remain intact as the temperature is lowered, eventually adhering to one another to form a gel. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 USN, Ctr Biomol Sci & Engn, Res Lab, Washington, DC 20375 USA. Coll France, F-75231 Paris 05, France. RP Singh, A (reprint author), USN, Ctr Biomol Sci & Engn, Res Lab, Washington, DC 20375 USA. NR 21 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0009-3084 J9 CHEM PHYS LIPIDS JI Chem. Phys. Lipids PD JUL PY 1998 VL 94 IS 1 BP 53 EP 61 DI 10.1016/S0009-3084(98)00023-1 PG 9 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 108UW UT WOS:000075284800005 ER PT J AU Qian, SJ Britzen, S Witzel, A Krichbaum, T Kraus, A Waltman, EB Valtaoja, E Aller, HD AF Qian, SJ Britzen, S Witzel, A Krichbaum, T Kraus, A Waltman, EB Valtaoja, E Aller, HD TI An analysis of the mm-radio outbursts in the gamma-ray source PKS 0528+134 SO CHINESE ASTRONOMY AND ASTROPHYSICS LA English DT Article DE extragalactic radio source; mm-radio burst; gamma-ray source; PKS 0528+134 ID SUPERLUMINAL MOTION; INJECTION MODEL; VARIABILITY; RADIATION; JETS; FREQUENCY; EVOLUTION; EMISSION; BLAZARS; SHOCK AB In this paper we use the "burst-injection model" of Qian et al. to analyze the evolution of the two am-radio outbursts in 1991/93 in PKS 0528 + 134. Comparison is made between the model and observed light curves at 12 frequencies between 230 GHz and 2.3 GHz. The model explains the observed variation quite well over a wide frequency range of similar to 50 : 1. C1 Chinese Acad Sci, Beijing Astron Observ, Beijing 100080, Peoples R China. Max Planck Inst Radioastron, D-5300 Bonn, Germany. USN, Res Lab, Washington, DC 20375 USA. Helsinki Univ Technol, Metsahova Radio Res Stn, FIN-02150 Espoo, Finland. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. RP Qian, SJ (reprint author), Chinese Acad Sci, Beijing Astron Observ, Beijing 100080, Peoples R China. NR 28 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0275-1062 J9 CHINESE ASTRON ASTR JI Chin. Astron. Astrophys. PD JUL-SEP PY 1998 VL 22 IS 3 BP 280 EP 287 DI 10.1016/S0275-1062(98)00038-1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 231XM UT WOS:000082336700005 ER PT J AU Ching, WM Wang, H Eamsila, C Kelly, DJ Dasch, GA AF Ching, WM Wang, H Eamsila, C Kelly, DJ Dasch, GA TI Expression and refolding of truncated recombinant major outer membrane protein antigen (r56) of Orientia tsutsugamushi and its use in enzyme-linked immunosorbent assays SO CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY LA English DT Article ID POLYMERASE CHAIN-REACTION; HIGH-LEVEL EXPRESSION; RICKETTSIA-TSUTSUGAMUSHI; SCRUB TYPHUS; IDENTIFICATION; SERODIAGNOSIS; STRAIN; GENE; CLASSIFICATION; AMPLIFICATION AB The variable 56-kDa major outer membrane protein of Orientia tsutsugamushi is the immunodominant antigen in human scrub typhus infections. The gene encoding this protein from Karp strain was cloned into the expression vector pET11a. The recombinant protein (r56) was expressed as a truncated nonfusion protein (amino acids 80 to 456 of the open reading frame) which formed an inclusion body when expressed in Escherichia coli BL21. Refolded r56 was purified and compared to purified whole-cell lysate of the Karp strain of O. tsutsltgamushi by immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) for reactivity with rabbit sera prepared against eight antigenic prototypes of O. tsutsugamushi as well as several other species of Rickettsiales and nonrickettsial antigens. Refolded r56 exhibited broad reactivity with the rabbit antisera against the Orientia prototypes, and the ELISA reactions with the r56 and Karp whole-cell lysate antigens correlated well (r = 0.81, n = 22, sensitivity compared to that of standard ELISA of 91%). Refolded r56 did not react with most antisera against other rickettsial species or control antigens (specificity = 92%, n = 13) using a positive cutoff value determined with eight uninfected rabbit sera. Refolded r56 was evaluated further by ELISA, using 128 sera obtained from patients with suspected scrub typhus from Korat, Thailand, and 74 serum specimens from healthy Thai soldiers. By using the indirect immunoperoxidase assay as the reference assay, the recombinant antigen exhibited a sensitivity and specificity of 93% or greater for detection of both IgG and IgM in the ELISA at 1:400 serum dilution. These results strongly suggest that purified r56 is a suitable candidate for replacing the density gradient-purified, rickettsia derived, whole-cell antigen currently used in the commercial dipstick assay available in the United States. C1 USN, Med Res Inst, Dept Infect Dis, Viral & Rickettsial Dis Program, Bethesda, MD 20889 USA. Armed Forces Res Inst Med Sci, Thai Component, Bangkok 10400, Thailand. Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Div Communicable Dis & Immunol, Washington, DC 20307 USA. RP Ching, WM (reprint author), USN, Med Res Inst, Dept Infect Dis, Viral & Rickettsial Dis Program, Code 41,8901 Wisconsin Ave, Bethesda, MD 20889 USA. EM Chingw@nmripo.nmri.nnmc.navy.mil NR 45 TC 36 Z9 42 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 JUL PY 1998 VL 5 IS 4 BP 519 EP 526 PG 8 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZY123 UT WOS:000074588900019 PM 9665960 ER PT J AU Ingram, DT Lamichhane, CM Rollins, DM Carr, LE Mallinson, ET Joseph, SW AF Ingram, DT Lamichhane, CM Rollins, DM Carr, LE Mallinson, ET Joseph, SW TI Development of a colony lift immunoassay to facilitate rapid detection and quantification of Escherichia coli O157 : H7 from agar plates and filter monitor membranes SO CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY LA English DT Article ID HEMOLYTIC-UREMIC SYNDROME; HEMORRHAGIC COLITIS; FERMENTATION; INFECTION; OUTBREAK; ASSAY AB E. coli O157:H7 is a food-borne adulterant that can cause hemorrhagic ulcerative colitis and hemolytic uremic syndrome. Faced with an increasing risk of foods contaminated with E. coli O157:H7, food safety officials are seeking improved methods to detect and isolate E. coli O157:H7 in hazard analysis and critical control point systems in meat- and poultry-processing plants. A colony lift immunoassay was developed to facilitate the positive identification and quantification off. coli O157:H7 by incorporating a simple colony lift enzyme-linked immunosorbent assay with filter monitors and traditional culture methods. Polyvinylidene difluoride (PVDF) membranes (Millipore, Bedford, Mass.) were prewet with methanol and were used to make replicates of every bacterial colony on agar plates or filter monitor membranes that were then reincubated for 15 to 18 h at 36 +/- 1 degrees C, during which the colonies not only remained viable but were reestablished. The membranes were dried, blocked with blocking buffer (Kirkegaard and Ferry Laboratories [KPL], Gaithersburg, Md.), and exposed for 7 min to an affinity-purified horseradish peroxidase-labeled goat anti-E. call O157 antibody (KFL). The membranes were washed, exposed to a 3,3',5,5'-tetramethylbenzidine membrane substrate (TMB; KFL) or aminoethyl carbazole (AEC; Sigma Chemical Co., St. Louis, Mo.), rinsed in deionized water, and air dried. Colonies of E. coli O157:H7 were identified by either a blue (via TMB) or a red (via AEC) color reaction. The colored spots on the PVDF lift membrane were then matched to their respective parent colonies on the agar plates or filter monitor membranes. The colony lift immunoassay was tested with a wide range of genera in the family Enterobacteriaceae as well as different serotypes within the E. coli genus. The colony lift immunoassay provided a simple, rapid, and accurate method for confirming the presence off. call O157:H7 colonies isolated on filter monitors or spread plates by traditional culture methods. An advantage of using the colony lift immunoassay is the ability to test every colony serologically on an agar plate or filter monitor membrane simultaneously for the presence of the E. coli O157 antigen. This colony lift immunoassay has recently been successfully incorporated into a rapid-detection, isolation, and quantification system for E. coli O157:H7, developed in our laboratories for retail meat sampling. C1 Univ Maryland, Dept Microbiol, Enter Dis Lab, College Pk, MD 20742 USA. Univ Maryland, Dept Biol Resources Engn, College Pk, MD 20742 USA. Univ Maryland, Virginia Maryland Reg Coll Vet Med, College Pk, MD 20742 USA. Kirkegaard & Perry Labs, Gaithersburg, MD 20879 USA. USN, Med Res Inst, Enter Dis Program, Bethesda, MD 20889 USA. RP Joseph, SW (reprint author), Univ Maryland, Dept Microbiol, Enter Dis Lab, College Pk, MD 20742 USA. EM SJ113@umail.umd.edu NR 25 TC 17 Z9 17 U1 1 U2 5 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 JUL PY 1998 VL 5 IS 4 BP 567 EP 573 PG 7 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZY123 UT WOS:000074588900027 PM 9665968 ER PT J AU Jansen, DL Meade, BD Lynn, F Gray, GC Putnam, SD AF Jansen, DL Meade, BD Lynn, F Gray, GC Putnam, SD TI Evaluation of pertussis in US Marine Corps trainees - Reply SO CLINICAL INFECTIOUS DISEASES LA English DT Letter ID OPERATION-DESERT-SHIELD; RESPIRATORY-DISEASE; IMMUNE-RESPONSE; PENICILLIN-G; PROPHYLAXIS; INFECTIONS; BENZATHINE; MILITARY; VACCINE C1 US FDA, Ctr Biol Evaluat & Res, Rockville, MD 20852 USA. USN, Hlth Res Ctr, Emerging Illness Div, San Diego, CA 92152 USA. Univ Iowa, Coll Med, Dept Prevent Med & Environm Hlth, Iowa City, IA 52242 USA. RP Jansen, DL (reprint author), US FDA, Ctr Biol Evaluat & Res, 1401 Rockville Pike,HFM-490, Rockville, MD 20852 USA. NR 13 TC 1 Z9 1 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 JUL PY 1998 VL 27 IS 1 BP 231 EP 232 DI 10.1086/517693 PG 2 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZZ690 UT WOS:000074756900057 ER PT J AU Armstrong, KR Clark, TR Peterson, MR AF Armstrong, KR Clark, TR Peterson, MR TI Use of corn-husk nesting material to reduce aggression in caged mice SO CONTEMPORARY TOPICS IN LABORATORY ANIMAL SCIENCE LA English DT Article ID ENVIRONMENTAL ENRICHMENT; BEHAVIOR AB We examined the use of corn-husk nesting material as a means of reducing aggressive behavior in group-housed mice. The experiment was performed by using 128 BALB/cAnNHsd mice, Mice were randomly assigned (8 mice/cage) to one of two groups: one housed in cages enriched with nesting material in addition to standard bedding, the other housed in cages with standard bedding only. Each mouse was examined on days 4 and 7 for evidence of visible wounds, On day 4, the addition of nesting material significantly decreased aggressive behavior for the enriched group, as indicated by mean number of wounds per group, By day 7, the amount of aggression was the same between the two groups. We concluded that use of nesting material decreased aggressive behavior in the mice during the initial introduction phase by providing flexible avenues of escape for subordinate mice. In addition, mice derived enrichment benefits by being provided a diverse cage environment that promoted natural nesting behavior. C1 Armed Forces Inst Pathol, Dept Vet Pathol, Div Lab Anim Med, Washington, DC 20306 USA. Armed Forces Inst Pathol, Dept Repository & Res Serv, Washington, DC 20306 USA. USN, Med Ctr, San Diego, CA 92134 USA. RP Armstrong, KR (reprint author), Armed Forces Inst Pathol, Dept Vet Pathol, Div Lab Anim Med, Washington, DC 20306 USA. NR 13 TC 28 Z9 28 U1 1 U2 2 PU AMER ASSOC LABORATORY ANIMAL SCIENCE PI CORDOVA PA 70 TIMBERCREEK DR, SUITE 5, CORDOVA, TN 38018 USA SN 1060-0558 J9 CONTEMP TOP LAB ANIM JI Contemp. Top. Lab. Anim. Sci. PD JUL PY 1998 VL 37 IS 4 BP 64 EP 66 PG 3 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 127JV UT WOS:000076348200015 PM 12456148 ER PT J AU Johnson, DR Weidemann, AD AF Johnson, DR Weidemann, AD TI A tidal plume front and internal solitons SO CONTINENTAL SHELF RESEARCH LA English DT Article ID SOLITARY WAVES; BUOYANT AB A tidal plume front (internal tidal bore) propagating from the Apalachicola Bay outflow into the northern Gulf of Mexico is examined in a brief set of observations. Temperature and salinity time series showed a radially spreading "pool" of estuarine water with a character similar to a previously observed "turbulent rotor", and with a following packet of internal solitons. Features associated with these observations may be pertinent to interpretation of remotely sensed plumes and to predictive modeling. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Johnson, DR (reprint author), USN, Res Lab, Code 7330, Stennis Space Ctr, MS 39529 USA. 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 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD JUL PY 1998 VL 18 IS 8 BP 923 EP 928 DI 10.1016/S0278-4343(98)00022-3 PG 6 WC Oceanography SC Oceanography GA 124GT UT WOS:000076174600005 ER PT J AU McKinlay, JR Ross, EV Barrett, TL AF McKinlay, JR Ross, EV Barrett, TL TI Vesiculobullous reaction to diethyltoluamide revisited SO CUTIS LA English DT Article AB Diethyltoluamide is an effective insect repellent known to cause irritant dermatitis. We describe an interesting case resulting from a unique occupational exposure. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. Naval Med Ctr San Diego, Dept Dermatol, San Diego, CA 92134 USA. RP McKinlay, JR (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 3 TC 13 Z9 14 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD JUL PY 1998 VL 62 IS 1 BP 44 EP 44 PG 1 WC Dermatology SC Dermatology GA 100VE UT WOS:000074835400011 PM 9675533 ER PT J AU Allison, MA Schmidt, CP AF Allison, MA Schmidt, CP TI Reactivated urticaria pigmentosa SO CUTIS LA English DT Article ID MAST-CELL; MASTOCYTOSIS AB Urticaria pigmentosa is a rare dermatologic disorder characterized by cutaneous mastocytosis either in isolated or diffuse forms. The disease usually occurs before age 4, but does occur in adulthood. When it occurs in adults, it is associated with a higher incidence of systemic involvement and malignancy, We describe a case of reactivated urticaria pigmentosa temporary associated with acute contact dermatitis in an adult. We describe a practical screening method for systemic involvement and an approach to treatment. C1 USN, San Diego, CA 92152 USA. USNR, Palo Alto, CA USA. RP Allison, MA (reprint author), 11595 4 Compass Point Dr N, San Diego, CA 92126 USA. OI Allison, Matthew/0000-0003-0777-8272 NR 10 TC 0 Z9 1 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD JUL PY 1998 VL 62 IS 1 BP 47 EP 48 PG 2 WC Dermatology SC Dermatology GA 100VE UT WOS:000074835400013 PM 9675535 ER PT J AU Dupree, MT Boyer, JD Cobb, MW AF Dupree, MT Boyer, JD Cobb, MW TI Marjolin's ulcer arising in a burn scar SO CUTIS LA English DT Article ID SQUAMOUS-CELL CARCINOMA; SKIN AB Marjolin's ulcer-a term used to describe a malignancy arising in chronic ulcers of the skin, sinuses, scar tissue, and especially burn scars-occurs in two forms: an acute variant in which the malignant changes occur within a year of injury, and a chronic form in which the injury may precede the malignancy by decades. Illustrating the more common chronic form, we present the case of a 32-year old Haitian woman with an extensive squamous cell carcinoma arising from a burn scar on the dorsum of her right hand, with a review of the literature pertaining to burn scar carcinoma. C1 USN, Bethesda, MD 20084 USA. USN, Pearl Harbor, HI USA. RP Dupree, MT (reprint author), USN, Bethesda, MD 20084 USA. NR 29 TC 40 Z9 43 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD JUL PY 1998 VL 62 IS 1 BP 49 EP 51 PG 3 WC Dermatology SC Dermatology GA 100VE UT WOS:000074835400014 PM 9675536 ER PT J AU Lindler, KW AF Lindler, KW TI Use of multi-stage cascades to improve performance of thermoelectric heat pumps SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE thermoelectric; heat pump; spreadsheet; dosimeter AB A thermoelectric heat pump is a miniature solid state device used to pump small amounts of heat. Potential uses range from the cooling of electronic components to dorm size refrigerators. An ongoing study at the U.S. Naval Academy proposes to use a miniature thermoelectric heat pump to maintain a neutron dosimeter at near constant temperatures in order to obtain more accurate readings. Unfortunately, the coefficient of performance of the heat pump decreases rapidly with increasing temperature difference. The current study investigates the potential improvement in heat pump performance that can be obtained by cascading two or more heat pumps in series operation. Published by Elsevier Science Ltd. C1 USN Acad, Naval Architecture Ocean & Marine Engn Dept, Annapolis, MD 21402 USA. RP Lindler, KW (reprint author), USN Acad, Naval Architecture Ocean & Marine Engn Dept, Annapolis, MD 21402 USA. NR 2 TC 16 Z9 17 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0196-8904 J9 ENERG CONVERS MANAGE JI Energy Conv. Manag. PD JUL PY 1998 VL 39 IS 10 BP 1009 EP 1014 DI 10.1016/S0196-8904(97)10044-9 PG 6 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA ZN295 UT WOS:000073631600004 ER PT J AU Puranik, DB Guo, Y Singh, A Morris, RE Huang, A Salvucci, L Kamin, R David, V Chang, EL AF Puranik, DB Guo, Y Singh, A Morris, RE Huang, A Salvucci, L Kamin, R David, V Chang, EL TI Copper removal from fuel by solid-supported polyamine chelating agents SO ENERGY & FUELS LA English DT Article ID COMPLEXES; MEMBRANES; LIGANDS AB The presence of copper in hydrocarbon fuels impairs fuel stability and jet-engine performance. We report here the results of an investigation on the feasibility of removing copper from hydrocarbon liquid using chelators attached to various support materials. The chelators, 1,4,8, 11-tetraazacyclotetradecane (cyclam) and N-1-[3-(trimethoxysilyl)propyl] diethylenetriamine (DETA), were attached to polystyrene, agarose, or silica. Copper extraction from JP-5 and dodecane with the immobilized chelators, both cyclic (cyclam) and acyclic (DETA) ones, was performed and the amount of Cu(II) removed measured. AU of the immobilized chelators showed an ability to remove copper ions from jet fuel, but DETA bound to silica exhibited the best results and was used for further Cu(II) binding studies under column flow. Results from JP-5, dodecane, and water tests are reported, and the potential of this approach for removing Cu(II) from jet fuel is discussed. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. Geocenters Inc, Ft Washington, MD 20744 USA. Georgetown Univ, Dept Biochem & Mol Biol, Washington, DC 20007 USA. USN, Res Lab, Navy Technol Ctr Safety & Survivabil, Washington, DC 20375 USA. USN, Air Warfare Ctr, Trenton, NJ 08628 USA. RP Chang, EL (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Code 6930, Washington, DC 20375 USA. NR 26 TC 5 Z9 5 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD JUL-AUG PY 1998 VL 12 IS 4 BP 792 EP 797 DI 10.1021/ef980006y PG 6 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 101CZ UT WOS:000074853200018 ER PT J AU DeGiorgi, VG Thomas, ED Lucas, KE AF DeGiorgi, VG Thomas, ED Lucas, KE TI Scale effects and verification of modeling of ship cathodic protection systems SO ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS LA English DT Article DE cathodic protection; ship; geometric scale effects; modeling AB The impressed-current cathodic protection system designed for a U.S. Navy aircraft carrier is evaluated using boundary element techniques. Geometric scaling is introduced by the inclusion of relatively smaller features, such as a bilge keel. The ship is modeled using guidelines developed for a smaller craft. Increases in geometric size result in increases in electrical current demand. Effects of time in service and speed are incorporated by paint damage patterns and use of polarization responses obtained under increased velocity used to simulate ship dynamic conditions. Physical scale modeling of experimental results are used as the basis for evaluation of model accuracy. Detailed comparisons of computational and experimental results show good agreement. As in previous work, model simplification and material characterization accuracy are observed to have a major influence on overall analysis accuracy. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Mech Mat Branch, Washington, DC 20375 USA. USN, Res Lab, Environm Effects Branch, Washington, DC 20375 USA. RP DeGiorgi, VG (reprint author), USN, Res Lab, Mech Mat Branch, Washington, DC 20375 USA. NR 18 TC 17 Z9 21 U1 0 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0955-7997 J9 ENG ANAL BOUND ELEM JI Eng. Anal. Bound. Elem. PD JUL PY 1998 VL 22 IS 1 BP 41 EP 49 DI 10.1016/S0955-7997(98)80012-X PG 9 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 109LF UT WOS:000075323500004 ER PT J AU Bowman, KP Hoppel, K Swinbank, R AF Bowman, KP Hoppel, K Swinbank, R TI Stationary anomalies in stratospheric meteorological data sets SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ASSIMILATION AB Several northern hemisphere stratospheric meteorological data sets are shown to contain stationary anomalies. We consider four possible explanations for the anomalies: 1) real stationary-wave features; 2) biases in the analysis and assimilation methods; 3) errors in data input into the analysis and assimilation systems; and 4) tidal signals that are undersampled in the daily analyses. Because the easter:ly flow in the summer stratosphere is not consistent with stationary waves and the anomalies are present in multiple analyses. we conclude that the anomalies are a combination of biases in the input data and tidal signals that are aliased to zero frequency by daily sampling. Because the anomalies are large, they can have significant impacts on many applications of the data, including trajectories and chemical transport calculations. C1 Texas A&M Univ, Dept Meteorol, College Stn, TX 77842 USA. USN, Res Lab, Ctr Remote Sensing, Washington, DC 20375 USA. Univ Space Res Assoc, NASA, Goddard Space Flight Ctr, Data Assimilat Off, Greenbelt, MD 20771 USA. RP Bowman, KP (reprint author), Texas A&M Univ, Dept Meteorol, College Stn, TX 77842 USA. RI Bowman, Kenneth/A-1345-2012 OI Bowman, Kenneth/0000-0002-2667-8632 NR 12 TC 11 Z9 11 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUL 1 PY 1998 VL 25 IS 13 BP 2429 EP 2432 DI 10.1029/98GL01716 PG 4 WC Geosciences, Multidisciplinary SC Geology GA ZZ145 UT WOS:000074700200047 ER PT J AU Miskel, JF Norton, RJ AF Miskel, JF Norton, RJ TI Humanitarian early-warning systems SO GLOBAL GOVERNANCE LA English DT Article C1 USN, War Coll, Newport, RI 02840 USA. Tufts Univ, Fletcher Sch Law & Diplomacy, Medford, MA 02155 USA. RP Miskel, JF (reprint author), USN, War Coll, Newport, RI 02840 USA. NR 29 TC 0 Z9 0 U1 0 U2 0 PU LYNNE RIENNER PUBL INC PI BOULDER PA 1800 30TH ST SUITE 314, BOULDER, CO 80301 USA SN 1075-2846 J9 GLOB GOV JI Glob. Gov. PD JUL-SEP PY 1998 VL 4 IS 3 BP 317 EP 329 PG 13 WC International Relations SC International Relations GA 118LY UT WOS:000075841000004 ER PT J AU Song, G Cai, L AF Song, G Cai, L TI Robust position/force control of robot manipulators during constrained tasks SO IEE PROCEEDINGS-CONTROL THEORY AND APPLICATIONS LA English DT Article DE robot manipulators; tasking; control ID FORCE CONTROL; FRICTION COMPENSATION AB A new approach, employing sliding-mode based smooth robust compensators, has been developed for simultaneous position and force control of an uncertain robot manipulator performing constrained tasks in the presence of environmental stick-slip friction. Under the proposed approach, the robot manipulator can exert a preset amount of force on the environment while tracking along a desired trajectory with global asymptotic stability, as proved by Lyapunov's direct method. No exact knowledge of link parameters (including link masses, the centre of mass, and the moment of inertia of links) is required. Unlike other approaches, the one proposed here takes into consideration the environmental friction as well as its dependency on normal contact force, and compensates for the friction effect. Furthermore, the proposed controller produces smooth control action, and ensures the robot's smooth motion on the contact surface. A numerical example of a two-link robot performing a constrained task is presented as an illustration. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. Hong Kong Univ Sci & Technol, Dept Engn Mech, Kowloon, Peoples R China. RP USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. NR 16 TC 8 Z9 8 U1 1 U2 3 PU INST ENGINEERING TECHNOLOGY-IET PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1350-2379 J9 IEE P-CONTR THEOR AP JI IEE Proc.-Control Theory Appl. PD JUL PY 1998 VL 145 IS 4 BP 427 EP 433 DI 10.1049/ip-cta:19982114 PG 7 WC Automation & Control Systems; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Automation & Control Systems; Engineering; Instruments & Instrumentation GA 113LL UT WOS:000075552400008 ER PT J AU Lewis, T Volpano, D AF Lewis, T Volpano, D TI Wired and wired-er SO IEEE INTERNET COMPUTING LA English DT Editorial Material C1 Technol Assessment Grp, San Francisco, CA USA. USN, Postgrad Sch, Monterey, CA USA. RP Lewis, T (reprint author), Technol Assessment Grp, San Francisco, CA 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 1089-7801 J9 IEEE INTERNET COMPUT JI IEEE Internet Comput. PD JUL-AUG PY 1998 VL 2 IS 4 BP 97 EP 99 PG 3 WC Computer Science, Software Engineering SC Computer Science GA 111XT UT WOS:000075464600020 ER PT J AU Novarini, JC Caruthers, JW AF Novarini, JC Caruthers, JW TI A simplified approach to backscattering from a rough seafloor with sediment inhomogeneities SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE bottom interaction; bottom loss; bottom scattering; reverberation ID SEA-FLOOR; ACOUSTIC BACKSCATTER; SCATTERING; MODEL AB Current models used to predict the backscattering strength of the ocean door are either very involved, requiring geoacoustic parameters usually unavailable for the site in practical applications, or overly simplistic, relying mainly on empirical terms such as Lambert's law. In any case, solutions are very approximate and the problem is still far from being solved, In this paper, a model is presented that avoids empirical functional forms yet requires only a few physical parameters to describe the surficial sediments, often tabulated for typical sediments, The aim of this paper is to develop a simple algorithm far operational prediction of bottom reverberation with only one free parameter, i.e., the volume scattering coefficient. The algorithm combines a two-scale surface scattering model with scattered contributions originating from inhomogeneities within the sediments, taking into consideration the rough interface. No specific mechanism is assumed for scattering at the volume inhomogeneities; however, the inhomogeneities are assumed to be uniform and isotropic The volume scattering coefficient, combined with the bottom attenuation and density and referenced to the surface, plays a role similar to the Lambert's constant in empirical models. The model is exercised on a variety of published datasets for low and moderately high frequency. In general, the model performs very well for both fast and slow sediments, showing a definite improvement over Lambert's law. C1 Planning Syst Inc, Long Beach, MS 39560 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Novarini, JC (reprint author), Planning Syst Inc, Long Beach, MS 39560 USA. NR 27 TC 16 Z9 17 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 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD JUL PY 1998 VL 23 IS 3 BP 157 EP 166 DI 10.1109/48.701188 PG 10 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA ZZ281 UT WOS:000074713700001 ER PT J AU Stanic, S Goodman, RR Briggs, KB Chotiros, NP Kennedy, ET AF Stanic, S Goodman, RR Briggs, KB Chotiros, NP Kennedy, ET TI Shallow-water bottom reverberation measurements SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE modeling; scattering parameters; seafloor sediments; underwater acoustic measurements ID SEA-FLOOR; ACOUSTIC BACKSCATTERING; OCEAN BOTTOM; FREQUENCY; FLUCTUATIONS; ROUGHNESS; MODEL AB High-frequency bottom reverberation measurements were made at an experimental site in the Gulf of Mexico. The acoustic data were taken as a function of frequency (40-180 kHz) and grazing angle (4 degrees-33 degrees). The measured acoustic reverberation results are compared to predictions made by models developed by Jackson et al. and Boyle and Chotiros. The models used inputs from the analysis of sediment cores and stereo photography. The model predictions show differences from each other and from the data. The results show reverberation-level variabilities as a function of frequency that cannot be accurately predicted by these models. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Penn State Univ, Appl Res Lab, State Coll, PA 16804 USA. Univ Texas, Appl Res Lab, Austin, TX 78758 USA. RP Stanic, S (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 23 TC 21 Z9 26 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 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD JUL PY 1998 VL 23 IS 3 BP 203 EP 210 DI 10.1109/48.701192 PG 8 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA ZZ281 UT WOS:000074713700005 ER PT J AU Koo, KP LeBlanc, M Tsai, TE Vohra, ST AF Koo, KP LeBlanc, M Tsai, TE Vohra, ST TI Fiber-chirped grating Fabry-Perot sensor with multiple-wavelength-addressable free-spectral ranges SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE chirp gratings; Fabry-Perot resonators; fiberoptics; sensors; WDM AB We report the demonstration of a fiber-chirped grating Fabry-Perot (FP) sensor with large dynamic range and high resolution surpassing that of a conventional PP sensor, The chirped grating FP sensor functions as an array of collocated FP cavities with different wavelength addressable cavity lengths or free-spectral ranges, This sensor design allows large dynamic range and high resolution to be achieved in a single compact sensor head. Free-spectral range from 0.04 to 1.3 nm has been achieved, Using this device as a strain sensor, unambiguous (without fringe counting) strain measurements from 3 +/- 1 mu Strain (limited by probe source resolution) to 1300 mu Strain have been measured. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Largo, MD 20774 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. RP Koo, KP (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 5 TC 16 Z9 19 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 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD JUL PY 1998 VL 10 IS 7 BP 1006 EP 1008 DI 10.1109/68.681299 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZU386 UT WOS:000074191900031 ER PT J AU Williams, KJ Esman, RD AF Williams, KJ Esman, RD TI Photodiode dc and microwave nonlinearity at high currents due to carrier recombination nonlinearities SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE nonlinearities; photodetectors; photodiodes; p-i-n photodiodes; semiconductor device modeling; simulation ID DETECTOR; DIODES AB We present photodetector compression measurements to demonstrate the consequences of absorption in undepleted regions close to the depletion region of p-i-n photodiodes. This absorption can modify the frequency response of photodetectors operating above a few milliamperes. The frequency response shows power dependence and additional ripple and rolloff. C1 USN, Res Lab, Washington, DC 20375 USA. RP Williams, KJ (reprint author), USN, Res Lab, Code 5670, Washington, DC 20375 USA. NR 14 TC 36 Z9 36 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 JUL PY 1998 VL 10 IS 7 BP 1015 EP 1017 DI 10.1109/68.681302 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZU386 UT WOS:000074191900034 ER PT J AU Tufts, DW Ianniello, JP Lourtie, I Preisig, JC Moura, JMF AF Tufts, DW Ianniello, JP Lourtie, I Preisig, JC Moura, JMF TI The past, present and future of underwater acoustic signal processing SO IEEE SIGNAL PROCESSING MAGAZINE LA English DT Review ID TIME-DELAY ESTIMATION; MAXIMUM-LIKELIHOOD-ESTIMATION; SHALLOW-WATER ENVIRONMENT; ISLAND FEASIBILITY TEST; MULTIPATH DOMINANT ENVIRONMENTS; FOCUSED HORIZONTAL ARRAYS; MATCHED-FIELD INVERSION; SOURCE LOCATION DEVICES; REALIZABLE LOWER BOUNDS; SOURCE LOCALIZATION C1 Univ Rhode Isl, Kingston, RI 02881 USA. USN, Undersea Warfare Ctr, Washington, DC USA. Inst Super Tecn, Lisbon, Portugal. Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RP Tufts, DW (reprint author), Univ Rhode Isl, Kingston, RI 02881 USA. RI Magazine, Signal Processing/E-9947-2015; Lourtie, Isabel/B-5258-2016 OI Lourtie, Isabel/0000-0002-5852-2595 NR 362 TC 3 Z9 3 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1053-5888 J9 IEEE SIGNAL PROC MAG JI IEEE Signal Process. Mag. PD JUL PY 1998 VL 15 IS 4 BP 22 EP 51 PG 30 WC Engineering, Electrical & Electronic SC Engineering GA ZZ284 UT WOS:000074714000003 ER PT J AU Schneidewind, NF Ebert, C AF Schneidewind, NF Ebert, C TI Preserve or redesign legacy systems? SO IEEE SOFTWARE LA English DT Editorial Material AB Legacy software systems represent a significant investment but often become difficult to maintain as they age. Not only does technology evolve beyond them, but business needs change and may require adding or modifying functions. This introduction addresses the question of whether to maintain or replace a legacy system, and gives an overview of the alternatives in dealing with our software legacies. C1 USN, Postgrad Sch, Code ISSs, Monterey, CA 93943 USA. Alcatel Telecom, Antwerp, Belgium. RP Schneidewind, NF (reprint author), USN, Postgrad Sch, Code ISSs, Monterey, CA 93943 USA. NR 0 TC 8 Z9 8 U1 0 U2 1 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 JUL-AUG PY 1998 VL 15 IS 4 BP 14 EP + DI 10.1109/MS.1998.687937 PG 5 WC Computer Science, Software Engineering SC Computer Science GA ZY445 UT WOS:000074622000008 ER PT J AU Schneidewind, NF AF Schneidewind, NF TI How to evaluate legacy system maintenance SO IEEE SOFTWARE LA English DT Article ID SOFTWARE AB Drawing on extensive data From the NASA Space Shuttle's guidance software, Schneidewind proposes a method for evaluating the effectiveness of legacy software maintenance efforts. He provides several formulas for tracking maintenance stability-defined as increasing functionality with decreasing failures, over time-and offers data that supports their validity. Schneidewind also provides tips for applying his formulas to different projects. C1 USN, Postgrad Sch, Code ISSs, Monterey, CA 93943 USA. RP USN, Postgrad Sch, Code ISSs, Monterey, CA 93943 USA. EM nschneid@nps.navy.mil NR 9 TC 3 Z9 4 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 EI 1937-4194 J9 IEEE SOFTWARE JI IEEE Softw. PD JUL-AUG PY 1998 VL 15 IS 4 BP 34 EP + DI 10.1109/52.687942 PG 10 WC Computer Science, Software Engineering SC Computer Science GA ZY445 UT WOS:000074622000013 ER PT J AU Waters, WM Patel, DP Trunk, GV AF Waters, WM Patel, DP Trunk, GV TI Optimum number of faces of a volume-scanning active array radar SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Letter AB The problem of finding the optimal number of phased array faces for performing hemispheric volume surveillance is considered. Assuming the detection performance is the same in all beam positions and the total number of modules are constant, it is shown that the optimal number of array faces is three. This is true when coverage extends to the zenith and to 45 degrees elevation. It is also true whether the array faces are operating simultaneously or sequentially. C1 USN, Div Radar, Res Lab, Washington, DC 20375 USA. RP Waters, WM (reprint author), USN, Div Radar, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 8 TC 8 Z9 9 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 JUL PY 1998 VL 34 IS 3 BP 1032 EP 1037 DI 10.1109/7.705924 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 106DA UT WOS:000075113400045 ER PT J AU Janaswamy, R AF Janaswamy, R TI A curvilinear coordinate-based split-step parabolic equation method for propagation predictions over terrain SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE nonhomogeneous media; propagation ID IRREGULAR TERRAIN; TROPOSPHERE; MODEL AB Propagation of radiowaves over irregular terrain and in an inhomogeneous atmosphere is solved by the parabolic equation method using the split-step Fourier algorithm on a terrain-conformal mesh. A piece,vise continuous coordinate system is generated by the specification of: 1) the terrain profile shape at discrete points and 2) an upper height. The resulting mesh is conformal to the terrain at the lower boundary a:nd gradually flattens off at the maximum height. In addition to preserving the number of points on any vertical line between the terrain and the maximum height from one range step to another, the coordinate transformation used in the paper produces a correction term in the refractive index whose gradient diminishes with height. As a result, the sampling requirements over steep terrain are relaxed when compared to the Beilis-Tappert transformation. Formulation and results are given both for the horizontal and vertical polarizations. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Janaswamy, R (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. NR 22 TC 17 Z9 18 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 JUL PY 1998 VL 46 IS 7 BP 1089 EP 1097 DI 10.1109/8.704813 PG 9 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 107ND UT WOS:000075214600018 ER PT J AU Song, GB Mukherjee, R AF Song, GB Mukherjee, R TI A comparative study of conventional nonsmooth time-invariant and smooth time-varying robust compensators SO IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY LA English DT Article DE bang-bang control; compensation; robustness; smooth compensator; stability; uniform ultimate boundedness; variable structure systems ID ROBOT MANIPULATORS; SYSTEMS; DESIGN AB Variable structure-based robust compensators are general approaches to deal with uncertain nonlinear dynamic systems. The bang-bang (discontinuous-type) compensator and the saturation (continuous-type) compensator are the two common robust compensators used in variable structure controllers. This paper presents a comparative study of these two nonsmooth time-invariant robust compensators with a smooth time-varying compensator and reveals the superiority of the smooth time-varying compensator over the nonsmooth robust compensators. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. Michigan State Univ, Dept Mech Engn, E Lansing, MI 48824 USA. RP Song, GB (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RI Mukherjee, Ranjan/A-7518-2009 NR 14 TC 38 Z9 38 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 1063-6536 J9 IEEE T CONTR SYST T JI IEEE Trans. Control Syst. Technol. PD JUL PY 1998 VL 6 IS 4 BP 571 EP 576 DI 10.1109/87.701355 PG 6 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA ZV216 UT WOS:000074282000013 ER PT J AU Abrahams, J AF Abrahams, J TI Variable-length unequal cost parsing and coding for shaping SO IEEE TRANSACTIONS ON INFORMATION THEORY LA English DT Article DE block-to-variable-length source coding; Lempel-Even-Cohn algorithm; shaping; unequal costs coding; variable-length-to-block source coding; Varn algorithm AB Shaping codes can be obtained from optimal unequal cost coding algorithms due to Lempel, Even, and Cohn in the variable-length-to-block case and to Varn in the block-to-variable-length case. The former is related to ad hoc approaches to shaping previously described while the latter is novel in the shaping context. C1 Off Naval Res, Math Comp & Informat Sci Div, Arlington, VA 22217 USA. RP Rutgers State Univ, DIMACS, Piscataway, NJ 08854 USA. EM abrahams@dimacs.rutgers.edu NR 12 TC 3 Z9 3 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9448 EI 1557-9654 J9 IEEE T INFORM THEORY JI IEEE Trans. Inf. Theory PD JUL PY 1998 VL 44 IS 4 BP 1648 EP 1650 DI 10.1109/18.681344 PG 3 WC Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA ZV269 UT WOS:000074287700030 ER PT J AU Chirita, M Robins, G Stamps, RL Sooryakumar, R Filipkowski, ME Gutierrez, CJ Prinz, GA AF Chirita, M Robins, G Stamps, RL Sooryakumar, R Filipkowski, ME Gutierrez, CJ Prinz, GA TI Spin waves and interlayer coupling in CoFe/Mn/CoFe structures SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 7th Joint MMM-Intermag Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA DE multilayers; exchange coupling : biquadratic; antiferromagnetic; spin waves; light scattering AB Coupling mechanisms between Co0.75Fe0.25 films separated by Mn layers are investigated using Brillouin light scattering from thermal spin waves. Observed applied field and Mn thickness dependences of acoustic and optic type spin wave frequencies are discussed in terms of exchange coupling and magnetic order in the Mn. C1 Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Arkansas, Dept Phys, Fayetteville, AR 72701 USA. SW Texas State Univ, Dept Phys, San Marcos, TX 78666 USA. USN, Res Lab, Washington, DC 20375 USA. RP Chirita, M (reprint author), Ohio State Univ, Dept Phys, 174 W 18Th Ave, Columbus, OH 43210 USA. RI Stamps, Robert/E-7304-2011 OI Stamps, Robert/0000-0003-0713-4864 NR 4 TC 0 Z9 0 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1998 VL 34 IS 4 BP 885 EP 887 DI 10.1109/20.706300 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 101CP UT WOS:000074852300021 ER PT J AU Bussmann, K Cheng, SF Prinz, GA Hu, Y Gutmann, R Wang, D Beech, R Zhu, J AF Bussmann, K Cheng, SF Prinz, GA Hu, Y Gutmann, R Wang, D Beech, R Zhu, J TI CPP giant magnetoresistance of NiFeCo/Cu/CoFe/Cu multilayers SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 7th Joint MMM-Intermag Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA DE CPP GMR; magnetic multilayers; chemical-mechanical polishing; current flow modeling; magnetoelectronic devices ID PERPENDICULAR MAGNETORESISTANCE; MAGNETIC MULTILAYERS; MICROSTRUCTURES AB CPP (Current perpendicular-to-plane) magnetotransport measurements have been performed on lithographically patterned magnetic multilayers of NiFeCo/Cu/CoFe/Cu, We implement chemical-mechanical polishing produce very low Cu-Cu interface resistance that allows accurate, intrinsic giant magnetoresistance (GMR) values to be obtained, Measured GMR is found to be dependent on device size but can be interpreted as the change in the resistivity of the magnetic multilayer and the effects of nonuniform current distribution. Computer simulations account for the non-uniform current distribution and allow us to determine the intrinsic CPP GMR and verify the negligible contact resistance in these structures. C1 USN, Res Lab, Washington, DC 20375 USA. Rensselaer Polytech Inst, Troy, NY 12180 USA. Nonvolatile Elect Inc, Eden Prairie, MN 55344 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RP Bussmann, K (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 10 TC 13 Z9 13 U1 2 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1998 VL 34 IS 4 BP 924 EP 926 DI 10.1109/20.706313 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 101CP UT WOS:000074852300034 ER PT J AU Johnson, M Bennett, BR Yang, MJ Miller, MM Shanabrook, BV AF Johnson, M Bennett, BR Yang, MJ Miller, MM Shanabrook, BV TI Hybrid ferromagnet-semiconductor nonvolatile gate SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 7th Joint MMM-Intermag Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA ID SPIN AB A novel magnetoelectronic device for digital applications is presented, and characteristics of a Nonvolatile Random Access Memory (NRAM) cell are discussed. A prototype cell with micron dimensions and with binary output states of 0 and 80 mV has been demonstrated at room temperature. Device fabrication requires only two lithographic levels, one for a Hall cross and one for an electrically isolated, microstructured bistable ferromagnetic him. Locally strong magnetic fringe fields from the edge of the film generate a Hall voltage in the semiconductor. The sign of the fringe field, as well as the polarity of the Hall voltage, is switched by reversing the in-plane magnetization of the ferromagnet. The device is inverse scalable: output characteristics improve as dimensions shrink. A high-density, solid state NRAM with nsec read, write and access times could replace both DRAM and magnetic disk drives in most computer environments, eliminating redundancy in memory systems. C1 USN, Res Lab, Washington, DC 20375 USA. RP Johnson, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 11 TC 9 Z9 10 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1998 VL 34 IS 4 BP 1054 EP 1059 DI 10.1109/20.706355 PN 1 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 101CP UT WOS:000074852300074 ER PT J AU Teter, JP Sendaula, MH Vranish, J Crawford, EJ AF Teter, JP Sendaula, MH Vranish, J Crawford, EJ TI Magnetostrictive linear motor development SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 7th Joint MMM-Intermag Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA DE linear motor; magnetostriction; transient model AB We are currently designing a high force linear motor that utilizes the inchworm principle coupled with multi-phase actuation. The efficient design of a 17 MV force linear motor that utilizes the magnetostrictive material Terfenol-D requires a transient electromechanical model to determine the operating parameters. The model is described and results indicated. It is found that control of the frequency and current inputs are all that is necessary to control the speed and power handling ability of the motor. Resonant operation is discussed along with increased efficiency power actuation schemes. C1 USN, Ctr Surface Warfare, W Bethesda, MD 20817 USA. Temple Univ, Philadelphia, PA 19122 USA. Goddard Space Flight Ctr, Greenbelt, MD 20071 USA. NAVSSES, Philadelphia, PA 19112 USA. RP Teter, JP (reprint author), USN, Ctr Surface Warfare, Code 684, W Bethesda, MD 20817 USA. NR 6 TC 7 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1998 VL 34 IS 4 BP 2081 EP 2083 DI 10.1109/20.706805 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 101CP UT WOS:000074852300407 ER PT J AU Becker, SI Wang, RB Hedstrom, RC Aguiar, JC Jones, TR Hoffman, SL Gardner, MJ AF Becker, SI Wang, RB Hedstrom, RC Aguiar, JC Jones, TR Hoffman, SL Gardner, MJ TI Protection of mice against Plasmodium yoelii sporozoite challenge with P-yoelii merozoite surface protein 1 DNA vaccines SO INFECTION AND IMMUNITY LA English DT Article ID AOTUS MONKEYS; TERMINAL FRAGMENT; IMMUNE-RESPONSE; MALARIA VACCINE; RECOMBINANT; FALCIPARUM; ANTIGEN; INFECTION; IMMUNIZATION; PRECURSOR AB Immunization of mice with DNA vaccines encoding the full-length form and C and N termini of Plasmodium yoelii merozoite surface protein 1 provided partial protection against sporozoite challenge and resulted in boosting of antibody titers after challenge. In C57BL/6 mice, two DNA vaccines provided protection comparable to that of recombinant protein consisting of the C terminus in Freund's adjuvant. C1 USN, Med Res Inst, Malaria Program, Bethesda, MD 20889 USA. Pan Amer Hlth Org, Washington, DC 20037 USA. Univ Baltimore, Dept Microbiol & Immunol, Baltimore, MD 21201 USA. RP Hoffman, SL (reprint author), USN, Med Res Inst, Malaria Program, 12300 Washington Ave, Rockville, MD 20852 USA. NR 25 TC 33 Z9 34 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0019-9567 J9 INFECT IMMUN JI Infect. Immun. PD JUL PY 1998 VL 66 IS 7 BP 3457 EP 3461 PG 5 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA ZW149 UT WOS:000074379900063 PM 9632624 ER PT J AU Krowne, CM AF Krowne, CM TI Inhomogeneous ferrite microstrip circulator 2D dyadic Green's function for penetrable walls SO INTERNATIONAL JOURNAL OF ELECTRONICS LA English DT Article AB Relaxation of the hard wall electomagnetic assumptions commonly applied to inhomogeneous microstrip circulators is carried out here by converting magnetic walls into interfacial walls. By viewing the source point as a singularity on the device boundary contour and using mode-matching, a new dyadic Green's function is found. The new dyadic Green's function allows fields and s-parameters to be found dependent on the external material permittivity epsilon(d) and permeability mu(d). C1 USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Washington, DC 20375 USA. RP Krowne, CM (reprint author), USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Code 6850-3, Washington, DC 20375 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0020-7217 J9 INT J ELECTRON JI Int. J. Electron. PD JUL PY 1998 VL 85 IS 1 BP 121 EP 127 DI 10.1080/002072198134409 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA ZU185 UT WOS:000074170800011 ER PT J AU Hedstrom, RC Doolan, DL Wang, RB Kumar, A Sacci, JB Gardner, MJ Aguiar, JC Charoenvit, Y Sedegah, M Tine, JA Margalith, M Hobart, P Hoffman, SL AF Hedstrom, RC Doolan, DL Wang, RB Kumar, A Sacci, JB Gardner, MJ Aguiar, JC Charoenvit, Y Sedegah, M Tine, JA Margalith, M Hobart, P Hoffman, SL TI In vitro expression and in vivo immunogenicity of Plasmodium falciparum pre-erythrocytic stage DNA vaccines SO INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE LA English DT Article DE malaria; Plasmodium falciparum; DNA vaccine; pre-erythrocytic; immunogenicity ID SPOROZOITE SURFACE PROTEIN-2; HUMAN MALARIA PARASITE; CYTOTOXIC T-LYMPHOCYTES; CIRCUMSPOROZOITE PROTEIN; MONOCLONAL-ANTIBODIES; INFECTED HEPATOCYTES; EXPORTED PROTEIN-1; CELLS RECOGNIZE; BLOOD STAGES; YOELII AB DNA vaccine plasmids were constructed that encoded four pre-erythrocytic antigens from the human malaria parasite Plasmodium falciparum: circumsporozoite protein (PfCSP); sporozoite surface protein 2 (PfSSP2); carboxyl terminus of liver stage antigen 1 (PfLSA-1 c-term); and, exported protein 1 (PfExp-1). Antigen expression was evaluated in vitro by immunoblot analysis of tissue culture cells following transient transfection with each plasmid. Clearly detectable levels of expression depended upon, or were markedly enhanced by, fusion of the antigen encoding sequences in-frame with the initiation complex and peptide leader sequence of human tissue plasminogen activator protein. Mice injected with these plasmids produced antigen specific antibody and cytotoxic T lymphocyte responses. However, the magnitudes of the responses were not always predicted by the in vitro expression assay. The results of this study provided the basis for further testing of these plasmids in primates and the formulation of multi-component pre-erythrocytic DNA vaccines for efficacy testing in human volunteers. C1 USN, Med Res Inst, Malaria Program, Rockville, MD 20852 USA. WHO, Reg Off, Pan Amer Hlth Org, Washington, DC 20037 USA. Henry M Jackson Fdn, Rockville, MD 20852 USA. Univ Maryland, Dept Microbiol & Immunol, Baltimore, MD 21201 USA. Virogenet Corp, Troy, NY 12180 USA. Vical Inc, San Diego, CA 92121 USA. RP Hedstrom, RC (reprint author), USN, Med Res Inst, Malaria Program, 12300 Washington Ave, Rockville, MD 20852 USA. RI Doolan, Denise/F-1969-2015 NR 52 TC 30 Z9 30 U1 0 U2 0 PU PROFESSOR D A SPANDIDOS PI ATHENS PA 1, S MERKOURI ST, EDITORIAL OFFICE,, ATHENS 116 35, GREECE SN 1107-3756 J9 INT J MOL MED JI Int. J. Mol. Med. PD JUL PY 1998 VL 2 IS 1 BP 29 EP 38 PG 10 WC Medicine, Research & Experimental SC Research & Experimental Medicine GA 117DZ UT WOS:000075766500003 PM 9854139 ER PT J AU Rath, BB DeYoung, DJ AF Rath, BB DeYoung, DJ TI The Naval Research Laboratory: 75 years of materials innovation SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article C1 USN, Res Lab, Washington, DC 20375 USA. RP Rath, BB (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 9 TC 1 Z9 1 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD JUL PY 1998 VL 50 IS 7 BP 14 EP 19 DI 10.1007/s11837-998-0185-x PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA ZZ423 UT WOS:000074727900002 ER PT J AU Tuncer, IH Platzer, MF AF Tuncer, IH Platzer, MF TI Computational study of subsonic flow over a delta canard-wing-body configuration SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 14th Applied Aerodynamics Conference CY JUN 17-20, 1996 CL NEW ORLEANS, LOUISIANA SP Amer Inst Aeronaut & Astronaut AB Subsonic flowfields over a close-coupled, delta canard-wing-body configuration at angles of attack of 20, 24,2, and 30 deg are computed using the OVERFLOW Navier-Stokes solver Computed flowfields are presented in terms of particle traces, surface streamlines, and leeward-side surface pressure distributions for the canard-on and -off configurations. The interaction between the canard and the wing vortices, wing vortex breakdown, and the influence of the canard on vortex breakdown are identified, The comparison of the pressure data with the available experimental data at Re = 0.32 x 10(6) and Re = 1.4 x 10(6) shows a significant Reynolds-number dependence. Good agreement is obtained with the experiment for the canard-off configuration at all three angles of attack, and for the canard-on configuration at 20-deg angle of attack. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Tuncer, IH (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. NR 13 TC 2 Z9 4 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 JUL-AUG PY 1998 VL 35 IS 4 BP 554 EP 560 DI 10.2514/2.2359 PG 7 WC Engineering, Aerospace SC Engineering GA 107FJ UT WOS:000075196300006 ER PT J AU Ganguli, R Chopra, I Haas, DJ AF Ganguli, R Chopra, I Haas, DJ TI Simulation of helicopter rotor-system structural damage, blade mistracking, friction, and freeplay SO JOURNAL OF AIRCRAFT LA English DT Article AB Selected helicopter rotor faults are simulated by changes in stiffness, inertial, and aerodynamic properties of the damaged or mistracked blade(s), A rotor aeroelastic analysis based on finite elements in space and time and capable of modeling dissimilar blades is used to simulate the damaged rotor in forward flight. The various rotor faults modeled include chordwise imbalance, aerodynamic mistracking, localized cracks, distributed changes in blade stiffness properties modeling a stiffness defect and a manufacturing defect, friction and freeplay in the pitch-control system and the lag damper, and friction in the flap and lag hinge. Changes in blade tip response and rotor hub loads are identified for the selected faults and tables of rotor-system diagnostics are compiled. C1 Univ Maryland, Dept Aerosp Engn, Alfred Gessow Rotorcraft Ctr, College Pk, MD 20742 USA. USN, Warfare Ctr, Sea Based Aviat Off, Bethesda, MD 20084 USA. RP Ganguli, R (reprint author), United Technol Corp, Pratt & Whitney Aircraft, E Hartford, CT 06108 USA. RI Ganguli, Ranjan/B-2592-2010 NR 12 TC 21 Z9 23 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 JUL-AUG PY 1998 VL 35 IS 4 BP 591 EP 597 DI 10.2514/2.2342 PG 7 WC Engineering, Aerospace SC Engineering GA 107FJ UT WOS:000075196300011 ER PT J AU Kelso, JM Jones, RT Yunginger, JW AF Kelso, JM Jones, RT Yunginger, JW TI Anaphylaxis after initial ingestion of rambutan, a tropical fruit SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Article ID ALLERGENS C1 USN, Dept Internal Med, Div Allergy, Med Ctr, San Diego, CA 92152 USA. USN, Dept Clin Invest, Med Ctr, San Diego, CA 92152 USA. Mayo Clin & Mayo Fdn, Allerg Dis Res Lab, Rochester, MN 55905 USA. RP Kelso, JM (reprint author), USN, Dept Clin Res, Med Ctr, San Diego, CA 92134 USA. NR 7 TC 9 Z9 9 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD JUL PY 1998 VL 102 IS 1 BP 145 EP 146 DI 10.1016/S0091-6749(98)70066-1 PG 2 WC Allergy; Immunology SC Allergy; Immunology GA 102DX UT WOS:000074909500021 PM 9679859 ER PT J AU Shinohara, T Briski, T AF Shinohara, T Briski, T TI A comparison of traditional dosing and once-daily aminoglycoside dosing on non-specific antibiotic side-effects in adults SO JOURNAL OF ANTIMICROBIAL CHEMOTHERAPY LA English DT Letter C1 USN, San Diego Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, San Diego Med Ctr, Dept Pharm, San Diego, CA 92134 USA. RP Shinohara, T (reprint author), USN, San Diego Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-7453 J9 J ANTIMICROB CHEMOTH JI J. Antimicrob. Chemother. PD JUL PY 1998 VL 42 IS 1 BP 114 EP 115 DI 10.1093/jac/42.1.114 PG 2 WC Infectious Diseases; Microbiology; Pharmacology & Pharmacy SC Infectious Diseases; Microbiology; Pharmacology & Pharmacy GA 104KP UT WOS:000075013800018 PM 9700540 ER PT J AU Heath, ME AF Heath, ME TI Neuropeptide Y and Y(1)-receptor agonists increase blood flow through arteriovenous anastomoses in rat tail SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE neurotransmitter; vascular control; microspheres; thermal stress; laser Doppler flowmetry; venous occlusion plethysmography ID PANCREATIC-POLYPEPTIDE; Y-2 RECEPTORS; VASCULAR TONE; VASOCONSTRICTOR; PEPTIDES; NEURONS; GANGLIA; SYSTEM; FAMILY; NPY AB The purpose of this study was to characterize neuropeptide Y (NPY)-induced vasodilation in the rat tail. Sterile surgical technique was used (with pentobarbital sodium anesthesia) to equip rats with a jugular catheter and a blind-ended thermocouple reentrant tube next to the carotid artery. Tail skin and core temperature were measured with thermocouples during experiments. Tail skin blood flow was monitored with a laser Doppler flowmeter, and tail total blood flow and volume were measured with plethysmography. After baseline data were collected, saline, NPY (16, 32, 64, and 128 mu g/kg), [Leu(31) Pro(34)]NPY (63.25 mu g/kg), or NPY[13-36] (44.7 mu g/kg) was administered intravenously. Tail total blood flow volume, and tail skin temperature increased, whereas tail skin blood flow and core temperature decreased in response to both NPY- and the Y(1)-receptor agonist [Leu(31) Pro(34)]NPY but not in response to saline or NPY[13-36]. Studies conducted with the use of color microspheres demonstrated that arteriovenous anastomoses are involved in this NPY-induced vasodilation. C1 USN, Med Res Inst, Bethesda, MD 20889 USA. RP Heath, ME (reprint author), Biodivers Res & Applicat Assoc, POB 22683, San Diego, CA 92192 USA. EM MEHeath@compuserve.com NR 42 TC 12 Z9 12 U1 1 U2 1 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 JUL PY 1998 VL 85 IS 1 BP 301 EP 309 PG 9 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA ZZ038 UT WOS:000074689200043 PM 9655790 ER PT J AU Ridout, JA Reynolds, CA AF Ridout, JA Reynolds, CA TI Western Pacific warm pool region sensitivity to convective triggering by boundary layer thermals in the NOGAPS atmospheric GCM SO JOURNAL OF CLIMATE LA English DT Article ID GENERAL-CIRCULATION MODELS; TOGA-COARE; SURFACE FLUXES; FORECAST MODEL; SATELLITE DATA; WIND STRESS; HEAT-FLUX; EL-NINO; OCEAN; PARAMETERIZATION AB The sensitivity of the atmospheric general circulation model of the Navy Operational Global Atmospheric Prediction System to a parameterization of convective triggering by atmospheric boundary layer thermals is investigated. The study focuses on the western Pacific warm pool region and examines the results of seasonal integrations of the model for the winter df 1987/88. A parameterization for thermal triggering of deep convection is presented that is based on a classification of the unstable boundary layer. Surface-based deep convection is allowed only for boundary layer regimes associated with the presence of thermals. The regime classification is expressed in terms of a Richardson number that reflects the relative significance of buoyancy and shear in the boundary layer. By constraining deep convection to conditions consistent with the occurrence of thermals thigh buoyancy to shear ratios), there is a significant decrease in precipitation over the southern portion of the northeast trade wind zone in the tropical Pacific and along the ITCZ. This decrease in precipitation allows for an increased flux of moisture into the region south of the equator corresponding to the warmest portion of the Pacific warm pool. Improvements in the simulated distribution of precipiration, precipitable water and low-level winds in the tropical Pacific are demonstrated. Over the western Pacific, the transition from free convective conditions associated with thermals to forced convective conditions is found to be primarily due to variations in mixed layer wind speed. Low-level winds thus play the major role in regulating the ability of thermals io initiate deep convection. The lack of coupling with the ocean in these simulations may possibly produce a distorted picture in this regard. C1 USN, Res Lab, Monterey, CA 93943 USA. RP Ridout, JA (reprint author), USN, Res Lab, 7 Grace Hopper Ave,Stop 2, Monterey, CA 93943 USA. EM ridout@nrlmry.navy.mil OI Reynolds, Carolyn/0000-0003-4690-4171 NR 40 TC 5 Z9 6 U1 0 U2 0 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 JUL PY 1998 VL 11 IS 7 BP 1553 EP 1573 DI 10.1175/1520-0442(1998)011<1553:WPWPRS>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 109MT UT WOS:000075326900005 ER PT J AU Sack, DA Lastovica, AJ Chang, SH Pazzaglia, G AF Sack, DA Lastovica, AJ Chang, SH Pazzaglia, G TI Microtiter assay for detecting Campylobacter spp. and Helicobacter pylori with surface gangliosides which bind cholera toxin SO JOURNAL OF CLINICAL MICROBIOLOGY LA English DT Article ID GUILLAIN-BARRE-SYNDROME; GM1 GANGLIOSIDE; JEJUNI INFECTION; IMMUNOSORBENT-ASSAY; LIPOPOLYSACCHARIDES; COLI; ANTIBODIES AB Campylobacter jejuni with Gm1 ganglioside in the core of its lipopolysaccharide has been associated with Guillain-Barre syndrome, Since this epitope may be of considerable pathophysiologic importance and since this ganglioside binds cholera toxin, a rapid screening assay to detect bacteria that bind cholera toxin as an indication of Gm1 on their surfaces was developed, In the assay, bacterial lawns mere grown on agar plates, harvested with phosphate-buffered saline, boiled, and incubated with a standard concentration of cholera B subunit, Preparations from strains with Gm1 were observed to inhibit the binding of cholera B subunit to Gm1 in a microtiter enzyme-linked immunosorbent assay. By using this assay with two groups of strains, 37 positive strains were detected among the 197 tested. Species with positive isolates included C. jejuni, Campylobacter coli, and Helicobacter pylori. The assay is capable of testing large numbers of isolates and should prove useful in future clinical and epidemiological studies of bacteria with this epitope. C1 Johns Hopkins Univ, Dept Int Hlth, Vaccine Testing Unit, Baltimore, MD 21205 USA. Red Cross War Mem Childrens Hosp, Dept Med Microbiol, Cape Town, South Africa. USN, Med Res Inst, Enter Dis Program, Bethesda, MD USA. Univ Texas, Sch Publ Hlth, Dept Epidemiol, Houston, TX USA. RP Sack, DA (reprint author), Johns Hopkins Univ, Dept Int Hlth, Vaccine Testing Unit, 550 N Broadway,Suite 1001, Baltimore, MD 21205 USA. NR 26 TC 12 Z9 13 U1 0 U2 0 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0095-1137 J9 J CLIN MICROBIOL JI J. Clin. Microbiol. PD JUL PY 1998 VL 36 IS 7 BP 2043 EP 2045 PG 3 WC Microbiology SC Microbiology GA ZU042 UT WOS:000074155400040 PM 9650959 ER PT J AU Khokhlov, AM AF Khokhlov, AM TI Fully threaded tree algorithms for adaptive refinement fluid dynamics simulations SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID MESH REFINEMENT; EULER EQUATIONS; SHOCK-WAVES; GRIDS AB A fully threaded tree (FTT) for adaptive mesh refinement (AMR) of regular meshes is described. By using a tree threaded at all levels, tree traversals for finding nearest neighbors are avoided. All operations on a tree including tree modifications are O(N), where N is a number of cells and can be pel formed in parallel. An implementation of the tree requires 2N words of memory, In this paper, FTT is applied to the integration of the Euler equations of fluid dynamics. The integration on a tree can utilize Bur evaluation algorithms used for grids, but requires a different time-stepping strategy to be computationally efficient. An adaptive-mesh time-stepping algorithm is described in which different time steps are used at different levels of the tree, Time stepping and mesh refinement are interleaved to avoid extensive buffer layers of fine mesh which were otherwise required ahead of moving shocks. A filtering algorithm for removing high-frequency noise during mesh refinement is described. Test examples are presented, and the FTT performance is evaluated. (C) 1998 Academic Press. C1 USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. RP USN, Res Lab, Computat Phys & Fluid Dynam Lab, Code 6404, Washington, DC 20375 USA. EM ajk@lcp.nrl.navy.mil NR 36 TC 163 Z9 166 U1 0 U2 9 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD JUL 1 PY 1998 VL 143 IS 2 BP 519 EP 543 DI 10.1006/jcph.1998.9998 PG 25 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA ZY201 UT WOS:000074596400011 ER PT J AU DeSisto, WJ Rappoli, BJ AF DeSisto, WJ Rappoli, BJ TI Ultraviolet absorption sensors for precursor delivery rate control for metalorganic chemical vapor deposition of multiple component oxide thin films SO JOURNAL OF CRYSTAL GROWTH LA English DT Letter ID SPECTROSCOPY; MOVPE; PRESSURES; REACTOR; INSITU; GROWTH; OMVPE; BA AB We report the development of sensors for measuring the concentration of 2,2,6,6-tetramethyl-3,5-heptanedionate (thd) complexes of yttrium and copper in-situ, in the gas delivery system of a metalorganic chemical vapor deposition (MOCVD) reactor. The gas delivery system was modified to incorporate dual-beam ultraviolet absorption sensors accessed remotely with fiber optics. Spectral data were acquired for individual precursors at 4 s intervals using spectrograph/photodiode arrays. The measured absorption for individual precursors was used to determine concentration in the gas stream. Using the measured concentration, feedback control of the yttrium and copper thd complex molar flow rates was demonstrated to be better than one-half of one percent of the desired molar flow rate. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP DeSisto, WJ (reprint author), USN, Res Lab, Div Elect Sci & Technol, Code 6861, Washington, DC 20375 USA. NR 21 TC 8 Z9 8 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD JUL PY 1998 VL 191 IS 1-2 BP 290 EP 293 DI 10.1016/S0022-0248(98)00211-5 PG 4 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA ZZ399 UT WOS:000074725500044 ER PT J AU Moni, S AF Moni, S TI Application-specific image compression for multimedia applications SO JOURNAL OF ELECTRONIC IMAGING LA English DT Article AB In order to establish a synergy between the compression scheme and the intended processing of the compressed image, we develop a family of compression algorithms that can adapt to the specialized requirements imposed by the application. The focus of this work is on wavelet-based compression for still images. A family of eight compression schemes is proposed to address specialized multimedia requirements such as (i) partial evaluation of wavelet coefficients, (ii) asymptotic losslessness of the algorithms, (iii) tree-structure in the selected coefficients, and (iv) optimization of either energy compaction or coefficient retention. Experimental results, including fraction of coefficients evaluated, rate-distortion performance, and coefficient retention are presented. (C) 1998 SPIE and IS&T. [S1017-9909(98)00503-0]. C1 Cadence Design Syst, Sunnyvale, CA 94086 USA. USN, Air Warfare Ctr, Weap Div, China Lake, CA 93555 USA. RP Moni, S (reprint author), Cadence Design Syst, 555 N Mathilda Ave, Sunnyvale, CA 94086 USA. NR 24 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 JUL PY 1998 VL 7 IS 3 BP 464 EP 473 DI 10.1117/1.482589 PG 10 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA 222XZ UT WOS:000081811800007 ER PT J AU Euler, GJ Miller, GA Hutter, JW D'Alesandro, MM AF Euler, GJ Miller, GA Hutter, JW D'Alesandro, MM TI Interleukin-6 in neutrophils from peripheral blood and inflammatory periradicular tissues SO JOURNAL OF ENDODONTICS LA English DT Article ID COLONY-STIMULATING FACTOR; NECROSIS-FACTOR-ALPHA; POLYMORPHONUCLEAR LEUKOCYTES; EXPRESSION; IL-6; CYTOKINES; CELLS AB Periradicular tissue samples were recovered recovered from patients undergoing endodontic surgery. Immuno-histochemical procedures were used to identify interleukin-6 (IL-6) present in the neutrophils associated with these lesions. Using specific polyclonal antibody, 15 to 20% of the neutrophils associated with the periradicular tissue lesions were positive for IL-6. IL-6-positive plasma calls and histiocytes were also abundant. Cytokine production by neutrophils from the peripheral blood of nondiseased individuals was also evaluated. The cells were stimulated with lipopolysaccharides and bacterial extracts of Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. Significant levels of IL-6 were produced by cells stimulated with Escherichia coli lipopolysaccharide B5 (933 pg/ml/10(7) neutrophils) and E. coli lipopolysaccharide B12 (791 pg/ml/10(7) cells) when compared with unstimulated cells (39.31 pg/ml/10(7) cells). There was a dose-dependent increase in IL-6 production when cells were stimulated for 24 h with 6 and 12 mu g/ml of A. actinomycetemcomitans extract. Less stimulation occurred with P. gingivalis, but it was also dose-dependent. Neutrophils resident in periradicular lesions may, therefore, provide a source of IL-6 in addition to that produced by tissue histiocytes and plasma cells. C1 USN, Dent Res Inst Detachment, Sch Dent, Bethesda, MD 20889 USA. USN, Sch Dent, Dept Endodont, Bethesda, MD 20814 USA. USN, Sch Dent, Dept Res, Bethesda, MD 20084 USA. RP Miller, GA (reprint author), USN, Dent Res Inst Detachment, Sch Dent, Bethesda, MD 20889 USA. NR 20 TC 14 Z9 15 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0099-2399 J9 J ENDODONT JI J. Endod. PD JUL PY 1998 VL 24 IS 7 BP 480 EP 484 DI 10.1016/S0099-2399(98)80051-4 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA ZX313 UT WOS:000074503000006 PM 9693575 ER PT J AU Millsaps, KT Reed, GL AF Millsaps, KT Reed, GL TI Reducing lateral vibrations of a rotor passing through critical speeds by acceleration scheduling SO JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 42nd International Gas Turbine and Aeroengine Congress and Exhibition CY JUN 02-05, 1997 CL ORLANDO, FLORIDA SP Int Gas Turbine Inst AB A method is presented for reducing the lateral response of an imbalanced rotor accelerating or decelerating through its first lateral bending critical speed by using a variable acceleration rate. A lumped parameter model along with a numerical integration scheme is used to simulate the response of a simply supported, single disk rotor during fast acceleration and deceleration through critical speed The results indicate that the maximum response and/or the total vibrational energy of a rotor passing through the critical speed can be reduced significantly by using a variable acceleration schedule. That is, reducing the acceleration rate after the nominal critical speed is passed. These predictions were verified experimentally for a single disk rotor. C1 USN, Postgrad Sch, Dept Mech Engn, Marine Prop Lab, Monterey, CA 93943 USA. RP Millsaps, KT (reprint author), USN, Postgrad Sch, Dept Mech Engn, Marine Prop Lab, Monterey, CA 93943 USA. NR 13 TC 11 Z9 14 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0742-4795 J9 J ENG GAS TURB POWER JI J. Eng. Gas. Turbines Power-Trans. ASME PD JUL PY 1998 VL 120 IS 3 BP 615 EP 620 DI 10.1115/1.2818190 PG 6 WC Engineering, Mechanical SC Engineering GA 110QZ UT WOS:000075393000027 ER PT J AU Neugebauer, M Forsyth, RJ Galvin, AB Harvey, KL Hoeksema, JT Lazarus, AJ Lepping, RP Linker, JA Mikic, Z Steinberg, JT von Steiger, R Wang, YM Wimmer-Schweingruber, RF AF Neugebauer, M Forsyth, RJ Galvin, AB Harvey, KL Hoeksema, JT Lazarus, AJ Lepping, RP Linker, JA Mikic, Z Steinberg, JT von Steiger, R Wang, YM Wimmer-Schweingruber, RF TI Spatial structure of the solar wind and comparisons with solar data and models SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY MAGNETIC-FIELD; HELIOSPHERIC CURRENT SHEET; CORONAL STREAMERS; ULYSSES; SPEED; SPACECRAFT; INSTRUMENT; POLE AB Data obtained by instruments on the Ulysses spacecraft during its rapid sweep through >90 degrees of solar latitude, crossing the solar equator in early 1995, were combined with data obtained near Earth by the Wind spacecraft to study the spatial structure of the solar wind and to compare to different models of the interplanetary magnetic field derived from solar observations. Several different source-surface models matched the double sinusoidal structure of the heliospheric current sheet (HCS) but with differences in latitude as great as 21 degrees. The source-surface model that included an interplanetary current sheet gave poorer agreement with observed current-sheet crossings during this period than did the other source-surface models or an MHD model. The differences between the calculated and observed locations of the HCS were minimized when 22 degrees of solar rotation was added to the constant-velocity travel time from the source surface to the spacecraft. The photospheric footpoints of the open field lines calculated from the models generally agreed with observations in the He 10,830 Angstrom line of the locations of coronal holes with the exceptions that (1) in some places, open field lines originated outside the coronal hole boundaries and (2) the models show apparently closed-field regions just inside some coronal hole boundaries. The patterns of mismatches between coronal hole boundaries and the envelopes of open field lines persisted over at least three solar rotations. The highest-speed wind came from the polar coronal holes, with the wind originating deeper within the hole being faster than the wind coming from near the hole boundary. Intermediate and slow streams originated in smaller coronal holes at low latitudes and from open field regions just outside coronal hole boundaries. Although the HCS threaded regions of low speed, low helium abundance, high ionization temperature, and a high ratio of magnesium to oxygen densities (a surplus of an element with low first-ionization potential), there was a great deal of variation in these parameters from one place to another along the HCS. The gradient of speed with latitude varied from 14 to 28 km s(-1) deg(-1). C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. Solar Phys Res Corp, Tucson, AZ 85718 USA. Ctr Space Sci & Astron, Stanford, CA 94305 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Sci Applicat Int Corp, San Diego, CA 92121 USA. Inst Space Sci Inst, CH-3012 Bern, Switzerland. USN, Res Lab, Div Space Sci, Washington, DC 20375 USA. Univ Bern, Inst Phys, CH-3012 Bern, Switzerland. RP Neugebauer, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 169-506, Pasadena, CA 91109 USA. RI Von Steiger, Rudolf/F-6822-2011; Galvin, Antoinette/A-6114-2013 OI Von Steiger, Rudolf/0000-0002-3350-0023; NR 40 TC 166 Z9 167 U1 1 U2 2 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 JUL 1 PY 1998 VL 103 IS A7 BP 14587 EP 14599 DI 10.1029/98JA00798 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZY130 UT WOS:000074589300008 ER PT J AU Fedder, JA Slinker, SP Lyon, JG AF Fedder, JA Slinker, SP Lyon, JG TI A comparison of global numerical simulation results to data for the January 27-28, 1992, Geospace Environment Modeling challenge event SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY MAGNETIC-FIELD; MAGNETOSPHERE AB A magnetohydrodynamic (MHD) numerical simulation model is used to study the magnetospheric state during the Geospace Environment Modeling (GEM) challenge period on January 27-28, 1992. Direct comparisons are made between the simulation results and the GEM Program data as summarized in the synoptic maps. The features we concentrate on are the cross-polar convection measurements and the ionospheric projection of magnetospheric boundaries. The results show good agreement at times and locations and poor agreement at other times. All in all, the results are rather mixed. We discuss the results and what they might mean for the accuracy of both the simulations and the synoptic maps..Moreover, we relate the results to other previous research on the cross-polar potential and draw guidance for future work. C1 USN, Res Lab, Beam Phys Branch, Div Plasma Phys, Washington, DC 20375 USA. Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA. SPA Inc, Landover, MD USA. George Mason Univ, Inst Computat Sci & Informat, Fairfax, VA 22030 USA. RP Fedder, JA (reprint author), USN, Res Lab, Beam Phys Branch, Div Plasma Phys, Code 6794,4555 Overlook Ave SW, Washington, DC 20375 USA. EM fedder@ppd.nrl.navy.mil; slinker@ppd.nrl.navy.mil; lyon@tinman.dartmouth.edu NR 11 TC 35 Z9 35 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 JUL 1 PY 1998 VL 103 IS A7 BP 14799 EP 14810 DI 10.1029/97JA03664 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZY130 UT WOS:000074589300025 ER PT J AU Park, SY Vadali, SR AF Park, SY Vadali, SR TI Touch points in optimal ascent trajectories with first-order state inequality constraints SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article; Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 07-10, 1995 CL BALTIMORE, MARYLAND SP AIAA ID VARIABLES AB Two and three-dimensional optimal ascent trajectories with a dynamic pressure inequality constraint are analyzed for the existence of nontrivial touch points. These studies verify for the first time that such trajectories can have the usual boundary area, where the constraint becomes active, as well as touch points, which are isolated points where the trajectory touches the constraint boundary. Some of the costates are discontinuous at the touch point. It is also possible to obtain additional insights into the nature of the Lagrange multipliers without solving the optimal control problem, specifically, for the numerical example treated, some of the costate variables can be shown to be zero at a touch point, if it exists. 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 14 TC 2 Z9 2 U1 0 U2 1 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 JUL-AUG PY 1998 VL 21 IS 4 BP 603 EP 610 PG 8 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA ZZ102 UT WOS:000074695900011 ER PT J AU Phillips, CA Malyevac, DS AF Phillips, CA Malyevac, DS TI Pulse motor optimization via mission charts for an exoatmospheric interceptor SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article; Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 11-13, 1997 CL NEW ORLEANS, LOUISIANA SP Amer Inst Aeronaut & Astronaut AB The selection of the pulse split and the interpulse delay of a two-pulse exoatmospheric midcourse stage for an exoatmospheric interceptor, which uses a kinetic kill vehicle (KKV) for a direct hit kill, is examined. Mission chart analysis is introduced along with system error trees and is used to select motor parameters that maximize the complete weapon system performance. In this analysis, the interceptor receives measured target updates from a weapon system consisting of a track sensor and a link to the interceptor. Location of the weapon system track sensor is not restricted hy this analysis. The interceptor states may be measured by the interceptor, by the weapon system track sensor, or by some combination of these. For specific weapon system and interceptor errors, the mission charts indicate upper and lower limits on the second-pulse burnout time. Ignition of the second pulse anywhere between these bounds leads to a high probability of a successful intercept with the earliest ignition time generally producing the highest average speed. These bounds are a function of 1) the KKV divert capability, 2) the weapon system and interceptor errors, 3) the fraction of second-pulse impulse allotted for midcourse correction divert, and 4) the propellant split between the first and second pulse. As the total mission time to intercept increases, the difference between the upper and lower bounds decreases until the mission becomes infeasible. The system errors and the pulse split determine the maximum feasible mission time. For a specific set of errors, there is a pulse split that optimizes the maximum feasible mission time and intercept range when all system constraints are considered. The maximum feasible intercept range is extremely sensitive to the system errors. C1 USN, Ctr Surface Warfare, Missile Syst Engn Branch, Weap Syst Dept,Dahlgren Div, Dahlgren, VA 22448 USA. RP Phillips, CA (reprint author), USN, Ctr Surface Warfare, Missile Syst Engn Branch, Weap Syst Dept,Dahlgren Div, G23,17320 Dahlgren Rd, Dahlgren, VA 22448 USA. NR 8 TC 6 Z9 6 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD JUL-AUG PY 1998 VL 21 IS 4 BP 611 EP 617 DI 10.2514/2.4279 PG 7 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA ZZ102 UT WOS:000074695900012 ER PT J AU Lawton, JA Jesionowski, RJ Zarchan, P AF Lawton, JA Jesionowski, RJ Zarchan, P TI Comparison of four filtering options for a radar tracking problem SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article; Proceedings Paper CT AIAA/BMDO 6th Annual Technology Readiness Conference CY AUG 18-22, 1997 CL SAN DIEGO, CALIFORNIA SP AIAA, BMDO AB Four different filtering options are considered for the problem of tracking an exoatmospheric ballistic target with no maneuvers. The four filters are an alpha-beta filter, an augmented alpha-beta filter, a decoupled Kalman filter, and a fully coupled extended Kalman filter. These filters are listed in the order of increasing computational complexity. All of the filters can track the target with some degree of accuracy. Although the pure alpha-beta filter appreciably lags the other filters in performance for this problem, its augmented version is very competitive with the extended Kalman filter under benign conditions. Perhaps the most surprising result is that under all conditions examined, the decoupled (linear) Kalman filter, which is at least an order of magnitude less computationally complex than We fully coupled extended Kalman filter, performs essentially the same as the extended Kalman filter. C1 USN, Ctr Surface Warfare, Space & Weap Syst Anal Div, Dahlgren Div, Dahlgren, VA 22448 USA. Sparta Inc, Syst Anal Div, Arlington, VA 22209 USA. Charles Stark Draper Lab Inc, Cambridge, MA 02139 USA. RP Lawton, JA (reprint author), USN, Ctr Surface Warfare, Space & Weap Syst Anal Div, Dahlgren Div, Dahlgren, VA 22448 USA. NR 9 TC 7 Z9 9 U1 0 U2 1 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 JUL-AUG PY 1998 VL 21 IS 4 BP 618 EP 623 DI 10.2514/2.4280 PG 6 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA ZZ102 UT WOS:000074695900013 ER PT J AU DeGiorgi, VG Lindner, DK McDermott, SH AF DeGiorgi, VG Lindner, DK McDermott, SH TI Combining modeling methodologies for improved understanding of smart material characteristics SO JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES LA English DT Article AB Smart materials are complex materials that contain both active and passive components. The system performance depends not only on active component performance capabilities but the synergistic response of the smart material and companion structure. Behavior is a result of interaction between diverse subsystems including, but not limited to, sensors, actuators, drive amplifiers and connecting digital electronics. An integrated model is developed which incorporates structural characteristics of a smart material and companion structure with a dynamic model of the amplifier used to power the smart material. Actuators are modeled using nonlinear constitutive laws and integrated with the dynamic model of the amplifier. The actuators have a significant structural influence on the smart material response. This interaction is obtained through a detailed finite element model used to determine the structural response of the smart material. Calculated displacements are compared for the dynamic model and the static finite element response model. The two analysis methodologies are used in conjunction to obtain a better understanding of the smart material performance. C1 USN, Res Lab, Multifunct Mat Branch, Washington, DC 20375 USA. Virginia Polytech Inst & State Univ, Bradley Dept Elect & Comp Engn, Blacksburg, VA 24061 USA. George Washington Univ, Sch Engn, Apprentice Program, Washington, DC 20052 USA. RP DeGiorgi, VG (reprint author), USN, Res Lab, Multifunct Mat Branch, Washington, DC 20375 USA. NR 17 TC 1 Z9 1 U1 0 U2 1 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 JUL PY 1998 VL 9 IS 7 BP 509 EP 521 PG 13 WC Materials Science, Multidisciplinary SC Materials Science GA 216UR UT WOS:000081463300003 ER PT J AU Max, MD Dillon, WP AF Max, MD Dillon, WP TI Oceanic methane hydrate: The character of the Blake Ridge hydrate stability zone, and the potential for methane extraction SO JOURNAL OF PETROLEUM GEOLOGY LA English DT Article ID BOTTOM SIMULATING REFLECTOR; GAS-HYDRATE; VELOCITY STRUCTURE; OUTER RIDGE; IN-SITU; SEDIMENTS; ATLANTIC; SEA AB Oceanic methane hydrates are mineral deposits formed from a crystalline "ice" of methane and water in sea-floor sediments (buried to less than about I km) in water depths greater than about 500 m; economic hydrate deposits are probably restricted to water depths of between 1.5 km and 4 km. Gas hydrates increase a sediment's strength both by "freezing" the sediment and by filling the pore spaces in a manner similar to water-ice in permafrost. Concentrated hydrate deposits may be underlain by significant volumes of methane gas, and these localities are the most favourable sites for methane gas extraction operations. Seismic reflection records indicate that trapped gas may blow-out naturally, causing large-scale seafloor collapse. In this paper, we consider both the physical properties and the structural integrity of the hydrate stability zone and the associated free gas deposits, with special reference to the Blake Ridge area, SE US offshore, in order to help establish a suitable framework for the safe, efficient, and economic recovery of methane from oceanic gas hydrates. We also consider the potential effects of the extraction of methane from hydrate (such as induced sea-floor faulting, gas venting, and gas-pocket collapse). We assess the ambient pressure effect on the production of methane by hydrate dissociation, and attempt to predict the likelihood of spontaneous gas flow in a production situation. C1 USN, Res Lab, Washington, DC 20375 USA. US Geol Survey, Woods Hole, MA 02543 USA. RP Max, MD (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 48 TC 19 Z9 21 U1 0 U2 10 PU SCIENTIFIC PRESS LTD PI BEACONSFIELD PA PO BOX 21, BEACONSFIELD, BUCKS, ENGLAND HP9 1NS SN 0141-6421 J9 J PETROL GEOL JI J. Pet. Geol. PD JUL PY 1998 VL 21 IS 3 BP 343 EP 358 DI 10.1111/j.1747-5457.1998.tb00786.x PG 16 WC Geosciences, Multidisciplinary SC Geology GA 112MH UT WOS:000075498000006 ER PT J AU O'Donnell, J Marmorino, GO Trump, CL AF O'Donnell, J Marmorino, GO Trump, CL TI Convergence and downwelling at a river plume front SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID DYNAMICS; SURFACE; BUOYANT; MODEL; WATERS; HEAD AB The small-scale structure of the circulation and hydrography at the frontal boundary of the Connecticut River plume in Long Island Sound has been resolved using a novel combination of instruments: a towed acoustic Doppler current profiler (ADCP) and a rigid array of current meters and conductivity-temperature sensors. Observations were made during the latter half of the eastward ebb tide, when the river plume was well established and the front was moving to the west at approximately 0.3 m s(-1) Two across-front transects revealed a horizontal convergence rate in the across-front velocity components at 0.6 m of 0.05-0.1 s(-1). This was associated with a salt-induced horizontal density gradient of 10(-2) kg/m(4). Observations obtained during a period in which the towed ADCP was caught in the zone of maximum surface convergence showed significant downwelling with a near-surface maximum of 0.2 m s(-1). Vertical velocities of this magnitude are consistent with observed mag nitudes of the convergence rate at 0.6 m assuming volume flux continuity and weak alongfront variations. Quantitative comparison of the velocity observations to the model of Garvine show reasonable agreement, though the vertical distribution of vertical shear and stratification could be improved. Within 20 m of the front, observations reveal regions of strong subsurface horizontal gradients in density and velocity that are not well described by the model. This limitation is a consequence of the assumption of similarity in the vertical structure of the fields. Both the magnitude and the across-front variation of the vertical velocity component observed agree with the theoretical predictions. The authors conclude, however, that the fundamental dynamics in the model are adequate to describe the general structure of the plume layer thickness. C1 Univ Connecticut, Dept Marine Sci, Groton, CT 06340 USA. USN, Res Lab, Washington, DC 20375 USA. RP O'Donnell, J (reprint author), Univ Connecticut, Dept Marine Sci, 1084 Shennecossett Rd, Groton, CT 06340 USA. NR 23 TC 57 Z9 57 U1 0 U2 6 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 JUL PY 1998 VL 28 IS 7 BP 1481 EP 1495 DI 10.1175/1520-0485(1998)028<1481:CADAAR>2.0.CO;2 PG 15 WC Oceanography SC Oceanography GA 104UP UT WOS:000075034500010 ER PT J AU Norheim, CA Herbers, THC Elgar, S AF Norheim, CA Herbers, THC Elgar, S TI Nonlinear evolution of surface wave spectra on a beach SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID 0.005-0.05 HZ MOTIONS; GRAVITY-WAVES; SHALLOW-WATER; FIELD OBSERVATIONS; BOUSSINESQ MODEL; SHELF AB The shoaling evolution of wave spectra on a beach with straight and parallel depth contours is investigated with a stochastic Boussinesq model. Existing deterministic Boussinesq models cast in the form of coupled evolution equations for the amplitudes and phases of discrete Fourier modes describe accurately the shoaling process for arbitrary incident wave conditions, but are numerically cumbersome for predicting the evolution of continuous spectra of natural wind-generated waves. The stochastic formulation used here, based on the closure hypothesis that phase coupling between quartets of wave components is weak, predicts the shoaling evolution of the continuous frequency spectrum and bispectrum of the wave field. The general characteristics of the stochastic model and the dependence of wave shoaling on nonlinearity, initial spectral shape, and bottom profile are illustrated with numerical simulations. Predictions of stochastic and deterministic Boussinesq models are compared with data from a natural barred ocean beach. Both models accurately reproduce the observed nonlinear wave transformation for a range of conditions. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. Washington State Univ, Pullman, WA 99164 USA. RP Herbers, THC (reprint author), USN, Postgrad Sch, Dept Oceanog, Code OC He, Monterey, CA 93943 USA. EM herbers@oc.nps.navy.mil NR 32 TC 23 Z9 23 U1 0 U2 3 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 JUL PY 1998 VL 28 IS 7 BP 1534 EP 1551 DI 10.1175/1520-0485(1998)028<1534:NEOSWS>2.0.CO;2 PG 18 WC Oceanography SC Oceanography GA 104UP UT WOS:000075034500014 ER PT J AU Nash, TJ Sanford, TWL Deeney, C Spielman, RB Seaman, J McGurn, J Jobe, DO Mock, RC Gilliland, TL Apruzese, JP Whitney, KG AF Nash, TJ Sanford, TWL Deeney, C Spielman, RB Seaman, J McGurn, J Jobe, DO Mock, RC Gilliland, TL Apruzese, JP Whitney, KG TI High temperature, dense cores in an aluminum wire array z-pinches observed by spatially-resolved spectroscopy SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID X-RAY-EMISSION; LABORATORY PLASMAS; IMPLOSIONS AB We have observed a hot, dense plasma core from an aluminum wire-array z pinch on the accelerator Saturn. A spatially resolved and temporally integrated crystal spectrometer shows aluminum K-shell free-bound continuum emission to be localized to less than 1 mm in diameter and to have a slope indicating a 1.4 keV electron temperature. A keV-filtered temporally resolved pinhole camera corroborates the I mm diameter plasma and a filtered photoconducting detector shows the temporal FWHM of the 4 TW of Al K-shell emission to be 5 ns. Roughly half of the Al K-shell emissions are due to free-bound recombinations. The intensity of the free-bound continuum indicates a core electron density of 3e21/cc. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. USN, Res Lab, Washington, DC 20375 USA. RP Nash, TJ (reprint author), Sandia Natl Labs, MS 1194, Albuquerque, NM 87185 USA. NR 18 TC 4 Z9 4 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD JUL PY 1998 VL 60 IS 1 BP 97 EP 102 PG 6 WC Optics; Spectroscopy SC Optics; Spectroscopy GA ZM063 UT WOS:000073501000010 ER PT J AU Beaulieu, MR Alfriend, KT Jerardi, T AF Beaulieu, MR Alfriend, KT Jerardi, T TI Launch detection satellite system engineering error analysis SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB An orbiting detector of infrared energy may be used to detect the rocket plumes generated by ballistic missiles during the powered segment of their trajectory, By measuring the angular directions of arrival of the detections over several observations, the trajectory properties, launch location, and impact area may be estimated using a nonlinear least squares iteration procedure. Observations from two or more sensors may be combined to form stereoscopic lines of sight, increasing the accuracy of the algorithm, A computer model is presented of an estimation algorithm that determines what parameter, or combination of parameters, will have a significant effect on the error of the tactical parameter estimation. This model generates observation data and then, using the data, produces an estimate of the tactical parameters, i.e., the time, position, and heading at launch and burnout, and an impact time and position. For the expected range of values of each of the error sources, the line-of-sight errors, a combination of focal-plane and attitude errors, had the greatest effect on the estimation of the launch and impact points. C1 USN, Postgrad Sch, Space Syst Acad Grp, Monterey, CA 93943 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. RP Beaulieu, MR (reprint author), USN, USS Carl Vinson, Bremerton, WA 98310 USA. NR 6 TC 2 Z9 6 U1 0 U2 3 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 JUL-AUG PY 1998 VL 35 IS 4 BP 487 EP 495 DI 10.2514/2.3357 PG 9 WC Engineering, Aerospace SC Engineering GA 109VZ UT WOS:000075346000010 ER PT J AU Adeff, JA Hofler, TJ Atchley, AA Moss, WC AF Adeff, JA Hofler, TJ Atchley, AA Moss, WC TI Measurements with reticulated vitreous carbon stacks in thermoacoustic prime movers and refrigerators SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB Reticulated vitreous carbon has been successfully used as a stack material in thermoacoustic prime movers and refrigerators. It is a rigid glassy carbon material, with a porous spongelike structure. Test results indicate peak pressure amplitudes of up to 32% in a prime mover, and refrigeration performance comparable to that of a traditional plastic roll stack. (C) 1998 Acoustical Society of America. [S0001-4966(98)05505-2]. C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Adeff, JA (reprint author), USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. NR 10 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 JUL PY 1998 VL 104 IS 1 BP 32 EP 38 DI 10.1121/1.424055 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZY164 UT WOS:000074592700004 ER PT J AU Candy, JV Sullivan, EJ AF Candy, JV Sullivan, EJ TI Broadband model-based processing for shallow ocean environments SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID DOMAIN SIGNAL TRANSMISSION; SOURCE LOCALIZATION; TIME-DOMAIN; WAVE-GUIDE; SOURCE LOCATION; TRANSIENT; WATER AB Most acoustic sources found in the ocean environment are spatially complex and broadband, In the case of shallow water propagation, these source characteristics complicate the analysis of received acoustic data considerably. A common approach to the broadband problem is to decompose the received signal into a set of narrow-band lines. This then allows the problem to be treated as a multiplicity of narrow-band problems. Here a model-based approach is developed for the processing of data received on a vertical array from a broadband source where it is assumed that the propagation is governed by the normal-mode model. The goal of the processor is to provide an enhanced (filtered) version of the pressure at the array and the modal functions. Thus a pre-processor is actually developed, since one could think of several applications for these enhanced quantities such as localization, modal estimation, etc. It is well-known that in normal-mode theory a different modal structure evolves for each temporal frequency; thus it is not surprising that the model-based solution to this problem results in a scheme that requires a "bank" of narrow-band model-based processors-each with its own underlying modal structure for the narrow frequency band it operates over. The "optimal" Bayesian solution to the broadband pressure field enhancement and modal function extraction problem is developed. It is shown how this broadband processor can be implemented (using a suboptimal scheme) in pseudo real time due to its inherent parallel structure. A set of noisy broadband data is synthesized to demonstrate how to construct the processor and achieve a minimum variance (optimal Bayesian) design. It is shown that both broadband pressure-field and modal function estimates can be extracted illustrating the feasibility of this approach. (C) 1998 Acoustical Society of America. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. USN, Undersea Warfare Ctr, Newport, RI 02841 USA. RP Candy, JV (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-156, Livermore, CA 94550 USA. NR 31 TC 5 Z9 10 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 JUL PY 1998 VL 104 IS 1 BP 275 EP 287 DI 10.1121/1.423278 PG 13 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZY164 UT WOS:000074592700032 ER PT J AU Shifler, DA Kruger, J Moran, PJ AF Shifler, DA Kruger, J Moran, PJ TI Passivity and breakdown of carbon steel in organic solvent mixtures of propylene carbonate and dimethoxyethane SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article; Proceedings Paper CT Meeting of the Electrochemical-Society CY AUG 31-SEP 05, 1997 CL PARIS, FRANCE SP Electrochem Soc ID NICKEL-IRON ALLOY; STAINLESS-STEEL; ONLINE MS; WATER; BEHAVIOR; ELECTROLYTES; 1,2-DIMETHOXYETHANE; RADIOTRACER; LITHIUM; ELECTROPOLYMERIZATION AB The passivity and breakdown of passivity of 1018 carbon steel in propylene carbonate (PC) and 1,2-dimethoxyethane (DME) mixtures with 0.5 molar lithium hexafluoroarsenate supporting electrolyte were examined via several electrochemical and surface analytical methods. The PC-DME/0.5 M LiAsF6 mixtures ranged from 10 to 90 mol % PC. The results from the PC/DME mixtures were compared to passivating mechanisms found in pure PC and DME solutions. In PC-rich mixtures, the breakdown of passivity occurred near the oxidation potentials of either organic solvent. Premature breakdown of the carbon steel in PC-DME mixtures occurred at sulfide inclusions as was observed earlier in PC/0.5 M LiAsF6 solutions although passive films attempted to form at these inclusion sites in mixtures containing at least 10 mol % DME. As the DME content increased in the PC-DME mixtures, the passive films formed on bare steel surfaces possessed an increasing polymer film character. In 50 and 70 mol % DME solutions nonprotective polymer films were formed. The nonprotective nature of these films indicated that PC passivation mechanisms competed and interfered with the DME mechanism of electropolymerized film formation. Only in 10 mol % PC-90 mel: % DME mixtures were.protective electropolymerized films formed on 1018 carbon steel. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. Johns Hopkins Univ, Dept Mat Sci & Engn, Baltimore, MD 21218 USA. USN Acad, Dept Mech Engn, Annapolis, MD 21401 USA. RP USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. NR 68 TC 5 Z9 5 U1 1 U2 3 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 EI 1945-7111 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JUL PY 1998 VL 145 IS 7 BP 2396 EP 2404 DI 10.1149/1.1838649 PG 9 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZX043 UT WOS:000074474500029 ER PT J AU Bondi, MW Drake, AI Grant, I AF Bondi, MW Drake, AI Grant, I TI Verbal learning and memory in alcohol abusers and polysubstance abusers with concurrent alcohol abuse SO JOURNAL OF THE INTERNATIONAL NEUROPSYCHOLOGICAL SOCIETY LA English DT Article DE alcohol abuse; polydrug abuse; learning; memory; neuropsychology ID HUNTINGTONS-DISEASE; MAGNETIC-RESONANCE; PARKINSONS-DISEASE; COCAINE ABUSERS; POLYDRUG USERS; BRAIN CHANGES; YOUNG-ADULTS; DRUG-ABUSE; INTOXICATION; RECOGNITION AB To define the combined effects of drug and alcohol abuse on verbal learning and memory, 70 alcoholic and 80 polysubstance abuse (PSA) individuals with concurrent alcohol abuse were compared on a list learning task, the California Verbal Learning Test (CVLT). Despite demonstrating similar learning strategies, response styles, and error patterns, the PSA group nonetheless exhibited significantly greater recall deficits than the alcoholic group on the CVLT. These deficits were particularly evident in those who were heaviest abusers of cocaine. PSA participants did not, however, evidence greater recognition memory deficits. This pattern of greater deficits on recall than on recognition memory, as well as poor consolidation, is consistent with the initiation-retrieval difficulties of patient groups with subcortical dysfunction. It is concluded that the combined use of alcohol and drugs, cocaine in particular, may compound memory difficulties beyond what is typically observed in alcoholic individuals. C1 Calif State Univ San Marcos, San Marcos, CA 92096 USA. Univ Calif San Diego, Vet Affairs Med Ctr, San Diego, CA 92161 USA. USN, Reg Med Ctr, San Diego, CA USA. RP Bondi, MW (reprint author), VCSD, Sch Med, Dept Psychiat, 9500 Gillman Dr, La Jolla, CA 92093 USA. EM mbondi@ucsd.edu NR 52 TC 31 Z9 31 U1 5 U2 7 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 1355-6177 J9 J INT NEUROPSYCH SOC JI J. Int. Neuropsychol. Soc. PD JUL PY 1998 VL 4 IS 4 BP 319 EP 328 PG 10 WC Clinical Neurology; Neurosciences; Psychiatry; Psychology SC Neurosciences & Neurology; Psychiatry; Psychology GA 104ZF UT WOS:000075046600002 PM 9656605 ER PT J AU Volino, RJ AF Volino, RJ TI A new model for free-stream turbulence effects on boundary layers SO JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 42nd International Gas Turbine and Aeroengine Congress and Exhibition CY JUN 02-05, 1997 CL ORLANDO, FLORIDA SP Int Gas Turbine Inst ID TRANSITION AB A model has been developed to incorporate more of the physics of free-stream turbulence effects into boundary layer calculations. The transport in the boundary layer is modeled using three terms: (1) the molecular viscosity, nu; (2) the turbulent eddy viscosity, epsilon(T), as used in existing turbulence models; and (3) a new free-stream-induced eddy viscosity, epsilon(f). The three terms are added to give an effective total viscosity. The free-stream-induced viscosity is modeled algebraically with guidance from experimental data. It scales on the rms fluctuating velocity in the free stream, the distance from the wall, and the boundary layer thickness. The model assumes a direct tie between boundary layer and free-stream fluctuations, and a distinctly differ ent mechanism than the diffusion of turbulence front the free-stream to the boundary layer assumed in existing higher order turbulence models. The new model can be used in combination with any existing turbulence model. It is tested here in conjunction with a simple mixing length model and a parabolic boundary layer solver. Comparisons to experimental data are presented for flows with free-stream turbulence intensities ranging from 1 to 8 percent and for both zero and nonzero streamwise pressure gradient cases. Comparisons are good. Enhanced heat transfer in higher turbulence cases is correctly predicted The effect of the free-stream turbulence on mean velocity and temperature profiles is also well predicted. In turbulent flow, the log region in the inner part of the boundary layer is preserved, while the wake is suppressed. The new model provides a simple and effective improvement for boundary layer prediction. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Volino, RJ (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RI Volino, Ralph/G-9293-2011 NR 27 TC 31 Z9 34 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 JUL PY 1998 VL 120 IS 3 BP 613 EP 620 PG 8 WC Engineering, Mechanical SC Engineering GA 110DL UT WOS:000075364800030 ER PT J AU Ward, JF Friedlander, SF Kaplan, GW AF Ward, JF Friedlander, SF Kaplan, GW TI Hemangioma presenting as an ulceration of the scrotum SO JOURNAL OF UROLOGY LA English DT Article C1 USN, Med Ctr, Dept Urol, San Diego, CA 92152 USA. Childrens Hosp & Hlth Ctr, Div Urol, San Diego, CA USA. Childrens Hosp & Hlth Ctr, Div Dermatol, San Diego, CA USA. RP Ward, JF (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 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 JUL PY 1998 VL 160 IS 1 BP 182 EP 183 DI 10.1016/S0022-5347(01)63087-8 PG 2 WC Urology & Nephrology SC Urology & Nephrology GA ZT003 UT WOS:000074037800081 PM 9628647 ER PT J AU Bermudez, VM AF Bermudez, VM TI Observation of adsorption and reaction of NH3 on crystalline Al2O3 under steady-state conditions using external-reflection infrared spectroscopy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; AUGER-ELECTRON SPECTROSCOPY; TIME SAMPLING ELECTRONICS; ENERGY-LOSS SPECTROSCOPY; EARLY-STAGE GROWTH; THIN-FILM GROWTH; FOURIER-TRANSFORM; ABSORPTION-SPECTROSCOPY; IN-SITU; FT-IR AB Thin crystalline films of Al2O3 have been grown by reaction of a NiAl(111) surface with chemisorbed O at elevated temperature. The resulting Al2O3/NiAl buried metal layer structure has then been used as a substrate for studies of NH3 adsorption under steady-state conditions at similar to 300 K and up to similar to 200 Torr. The technique used is polarization-modulated infrared reflection absorption spectroscopy, the application of which to in situ studies of surface chemistry is described in detail: Evidence is seen that suggests incorporation of N into the Al2O3, and adsorbed NH3 is detected under high (greater than or equal to 25 Torr) static pressures. [S0734-2101(98)07604-0]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Bermudez, VM (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 90 TC 12 Z9 12 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2572 EP 2580 DI 10.1116/1.581384 PG 9 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700087 ER PT J AU Silvestre, C Thompson, P Jernigan, G Simons, D AF Silvestre, C Thompson, P Jernigan, G Simons, D TI Boron incorporation with and without atomic hydrogen during the growth of doped layers on Si(100) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID MOLECULAR-BEAM EPITAXY; SCANNING-TUNNELING-MICROSCOPY; CHEMICAL-VAPOR-DEPOSITION; SILICON(001) SURFACE; MORPHOLOGY; STEPS AB Solid source molecular beam epitaxy Si growths were done with and without atomic hydrogen (AH) to investigate the impact of AH on B segregation and activation. A series of 3 or 50 nm thick B-doped Si layers separated by 200 nm of undoped Si were grown at 0.1 nm/s on Si(100) substrates. In separate experiments, 10(-4) Pa of AH was applied after (at 500, 600, and 710 degrees C) or during (at 710 degrees C) the 3 nm B-doped layer to determine if AH affected segregation. AH was applied before the 50 nm B-doped layer to observe if AH increased B activation between 600 and 800 degrees C. It was found that application of AH after the growth of the 3 nm B-doped layer had no effect on B segregation through 600 degrees C and increased B segregation at 710 degrees C, as measured by secondary ion mass spectrometry (SIMS). Application of AH during B-doped Si layer growth had no effect on B segregation. Application of 10(-3) Pa of AH for 100 s prior to growth of the 50 nm B-doped layer improved surface order, as measured by low energy electron diffraction, and, at T greater than or equal to 700 degrees C, increased B activation, as measured by spreading resistance profilometry (SRP). The differences between the SIMS and SRP data are postulated to be due to two forms of B: one electrically active and the other electrically inactive. The electrically inactive form is modeled by two paired B atoms on adjacent substitutional sites. [S0734-2101(98)07304-7]. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. NIST, Surface & Microanal Sci Div, Gaithersburg, MD 20899 USA. RP Silvestre, C (reprint author), USN, Res Lab, Div Elect Sci & Technol, Code 6812, Washington, DC 20375 USA. NR 24 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2619 EP 2624 DI 10.1116/1.581414 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700095 ER PT J AU Silvestre, C Jernigan, GG Twigg, ME Thompson, PE AF Silvestre, C Jernigan, GG Twigg, ME Thompson, PE TI Changes in morphology using atomic hydrogen during Si/Si1-xGex molecular beam epitaxy growth on Si (100) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID GE SURFACE SEGREGATION; LAYERS; IRRADIATION AB Si and Si1-xGex molecular beam epitaxial growths have been conducted with and without 10(-3) Pa atomic hydrogen (AH) overpressure to observe the effect of AH on surface morphology. Si1-xGex (x=0.1 and 0.2) layers 3 nm thick grown at 710 degrees C without AH showed flat epitaxy by transmission electron microscopy but identical layers grown in the presence of AH showed interface stress undulations. Stress undulations were also observed for a 20% Ge alloy grown with AH at 600 degrees C. For 30% Ge alloy layers grown at 710 degrees C, undulations were seen both with and without AH with a approximate to 250 nm period, however the amplitudes of the undulations were greater with AH. Low energy electron diffraction investigation of Si homoepitaxy revealed,at growth temperatures between 600 and 800 degrees C, improved epitaxy with 100 s of 10(-3) Pa AH. In combination, these results are evidence that AH has increased the adatom mobility. C1 USN, Res Lab, Washington, DC 20375 USA. RP USN, Res Lab, Code 6812, Washington, DC 20375 USA. EM thompson@estd.nrl.navy.mil NR 23 TC 6 Z9 6 U1 0 U2 0 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 1998 VL 16 IS 4 BP 1933 EP 1936 DI 10.1116/1.590110 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 110LN UT WOS:000075381400028 ER PT J AU Jensen, KL Yater, JE Zaidman, EG Kodis, MA Shih, A AF Jensen, KL Yater, JE Zaidman, EG Kodis, MA Shih, A TI Advanced emitters for next generation rf amplifiers SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID FOWLER-NORDHEIM EQUATION; FIELD-EMISSION; ELECTRON-EMISSION; DIAMOND FILMS; ARRAYS; RESOLUTION; CONES AB Next generation rf amplifiers, in particular the inductive output amplifiers (IOAs), will require electron sources characterized by high current density, high brightness, low emittance, and the ability to be emission gated. The strong interaction between the beam and the resonant or synchronous electromagnetic field may enable compact, highly efficient, and moderate gain X-band power booster amplifiers. An analysis of amplifier demands on generic emitter candidates is provided. Of the emitter candidates available, two (namely, field emitter arrays and wide-band-gap semiconductors) are amenable to an analysis predicated on a simple model of field emission from hyperbolas and ellipsoids. The simple model is used to investigate two problems of critical concern: for field emitter arrays (FEAs), we will investigate the conditions under which important space charge effects exist, and from the model predict optimum FEA performance characteristics for rf IOAs; for wide-band-gap materials, the simple model identifies parameters which limit the maximum electron transport across a metal-semiconductor interface, thereby limiting current flow. C1 USN, Res Lab, Elect Sci & Technol Div, Washington, DC 20357 USA. RP Jensen, KL (reprint author), USN, Res Lab, Elect Sci & Technol Div, Code 6840, Washington, DC 20357 USA. EM kevin.jensen@nrl.navy.mil RI Jensen, Kevin/I-1269-2015 OI Jensen, Kevin/0000-0001-8644-1680 NR 45 TC 13 Z9 13 U1 0 U2 1 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 JUL-AUG PY 1998 VL 16 IS 4 BP 2038 EP 2048 DI 10.1116/1.590126 PG 11 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 110LN UT WOS:000075381400045 ER PT J AU Nosho, BZ Weinberg, WH Zinck, JJ Shanabrook, BV Bennett, BR Whitman, LJ AF Nosho, BZ Weinberg, WH Zinck, JJ Shanabrook, BV Bennett, BR Whitman, LJ TI Structure of InAs/AlSb/InAs resonant tunneling diode interfaces SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 25th Annual Conference on the Physics and Chemistry of Semiconductor Interfaces CY JAN 18-22, 1998 CL SALT LAKE CITY, UTAH ID ENERGY ELECTRON-DIFFRACTION; SURFACE RECONSTRUCTIONS; GASB; ALSB; SUPERLATTICES; MICROSCOPY; GROWTH; PHOTOEMISSION; DISORDER; EPITAXY AB We have used in situ plan-view scanning tunneling microscopy to study the surfaces and interfaces within an InAs/AlSb/InAs resonant tunneling diodelike structure grown by molecular beam epitaxy. The nanometer and atomic-scale morphologies of the surfaces have been characterized following a number of different growth procedures. When InAs(001)-(2 x 4) is exposed to Sb-2 a bilayer surface is produced, with 1 monolayer (ML) deep (3 Angstrom) vacancy islands covering approximately 25% of the surface. Both layers exhibit a (1 x 3)-like reconstruction characteristic of an InSb-like surface terminated with >1 ML Sb, indicating that there is a significant amount of Sb on the surface. When 5 ML of AlSb is deposited on an Sb-terminated InAs surface, the number of layers observed on each terrace increases to three. Growth of an additional 22 ML of InAs onto the AlSb layer, followed by a 30 s interrupt under Sb-2, further increases the number of surface layers observed. The root-mean-square roughness is found to increase at each subsequent interface; however, on all the surfaces the roughness is less than or equal to 2 Angstrom. The surface roughness is attributed to a combination of factors, including reconstruction-related stoichiometry differences, kinetically limited diffusion during growth, and lattice-mismatch strain. Possible methods to reduce the roughness are discussed. (C) 1998 American Vacuum Society. C1 Univ Calif Santa Barbara, Ctr Quantized Elect Struct, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA. USN, Res Lab, Malibu, CA 90265 USA. RP Nosho, BZ (reprint author), Univ Calif Santa Barbara, Ctr Quantized Elect Struct, Santa Barbara, CA 93106 USA. EM brettn@engineering.ucsb.edu; Lloyd.Whitman@nrl.navy.mil RI Bennett, Brian/A-8850-2008; Whitman, Lloyd/G-9320-2011 OI Bennett, Brian/0000-0002-2437-4213; Whitman, Lloyd/0000-0002-3117-1174 NR 36 TC 18 Z9 18 U1 0 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 JUL-AUG PY 1998 VL 16 IS 4 BP 2381 EP 2386 DI 10.1116/1.590178 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 110LN UT WOS:000075381400105 ER PT J AU Michael, NL Nelson, JAE Kewalramani, VN Chang, G O'Brien, SJ Mascola, JR Volsky, B Louder, M White, GC Litman, DR Swanstrom, R O'Brien, TR AF Michael, NL Nelson, JAE Kewalramani, VN Chang, G O'Brien, SJ Mascola, JR Volsky, B Louder, M White, GC Litman, DR Swanstrom, R O'Brien, TR TI Exclusive and persistent use of the entry coreceptor CXCR4 by human immunodeficiency virus type 1 from a subject homozygous for CCR5 Delta 32 SO JOURNAL OF VIROLOGY LA English DT Article ID HIV-1 INFECTION; CELL-LINE; TROPIC HIV-1; RECEPTOR; AIDS; MIP-1-ALPHA; PROGRESSION; RETROVIRUS; MIP-1-BETA; RANTES AB Individuals who are homozygous for the 32-bp deletion in the gene coding for the chemokine receptor and major human immunodeficiency virus type 1 (HIV-1) coreceptor CCR5 (CCR5 -/-) lack functional cell surface CCR5 molecules and are relatively resistant to HIV-1 infection. HIV-1 infection in CCR5 -/- individuals, although rare, has been increasingly documented. We now report that the viral quasispecies from one such individual throughout disease is homogenous, T cell line tropic, and phenotypically syncytium inducing (SI); exclusively uses CXCR4; and replicates well in CCR5 -/- primary T cells. The recently discovered coreceptors BOB and Bonzo are not used. Although early and persistent SI variants have been described in longitudinal studies, this is the first demonstration of exclusive and persistent CXCR4 usage. With the caveat that the earliest viruses available from this subject were from approximately 4 years following primary infection, these data suggest that HIV-1 infection can be mediated and persistently maintained by viruses which exclusively utilize CXCR4. The lack of evolution toward the available minor coreceptors in this subject underscores the dominant biological roles of the major coreceptors CCR5 and CXCR4. This and two similar subjects (R. Biti, R. Ffrench, J. Young, B. Bennetts, G. Stewart, and T. Liang, Nat. Med. 3:252-253, 1997; I. Theodoreu, L. Meyer, M. Magierowska, C. Katlama, and C. Rouzioux, Lancet 349:1219-1220, 1997) showed relatively rapid CD4(+) T-cell declines despite average or low initial viral RNA load. Since viruses which use CXCR4 exclusively cannot infect macrophages, these data have implications for the relative infection of the T cell compartment versus the macrophage compartment in vivo and for the development of CCR5-based therapeutics. C1 NCI, Viral Epidemiol Branch, NIH, Rockville, MD 20852 USA. NCI, Lab Genom Divers, Rockville, MD 20852 USA. Henry M Jackson Fdn Advancement Mil Med, Rockville, MD USA. Walter Reed Army Inst Res, Div Retrovirol, Rockville, MD USA. USN, Med Res Inst, Dept Infect Dis, Bethesda, MD USA. Univ N Carolina, Lineberger Comprehens Canc Ctr, Chapel Hill, NC 27599 USA. Univ N Carolina, Div Hematol & Oncol, Chapel Hill, NC 27599 USA. Univ N Carolina, Dept Biochem & Biophys, Chapel Hill, NC 27599 USA. NYU Med Ctr, Skirball Inst, New York, NY 10016 USA. NYU Med Ctr, Howard Hughes Med Inst, New York, NY 10016 USA. RP O'Brien, TR (reprint author), NCI, Viral Epidemiol Branch, NIH, EPN 434,6130 Execut Blvd, Rockville, MD 20852 USA. FU NCI NIH HHS [T32 CA009156, T32-CA-09156, N01-CP-85649] NR 61 TC 135 Z9 138 U1 0 U2 0 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 JUL PY 1998 VL 72 IS 7 BP 6040 EP 6047 PG 8 WC Virology SC Virology GA ZU089 UT WOS:000074160500083 PM 9621067 ER PT J AU Klinman, DM Conover, J Bloom, ET Weiss, W AF Klinman, DM Conover, J Bloom, ET Weiss, W TI Immunogenicity and efficacy of a DNA vaccine in aged mice SO JOURNALS OF GERONTOLOGY SERIES A-BIOLOGICAL SCIENCES AND MEDICAL SCIENCES LA English DT Article ID CD4+ T-CELLS; CIRCUMSPOROZOITE PROTEIN; PLASMID DNA; OLD MICE; INTERFERON-GAMMA; GENE-EXPRESSION; VIRUS; YOUNG; INFLUENZA; CYTOKINE AB The immunogenicity and protective efficacy of a DNA vaccine encoding the circumsporozoite protein of the Plasmodium yoelii malaria parasite was evaluated in young (2 months) versus aged (>26 months) BALB/c mice. The primary and secondary humoral immune response of aged mice was 19- and 7-fold lower, respectively than that of similarly treated young animals (p <.01). Cytotoxic T lymphocyte activity in aged mice, was also lower than ill younger animals. The vaccine response of aged animals was characterized by a 6-fold increase in interleukin-4 and a 3-fold increase ill interferon-gamma (IFN-gamma) secreting cells, whereas in :young animals immunization only stimulated the production of the type I cytokine IFN-gamma. Overall, 80% of young vaccinated mice were protected from subsequent challenge with live malaria sporozoites whereas only 40% of aged mice were protected. These results are the first to demonstrate that DNA vaccination induces less effective immunity in aged than young animals. C1 US FDA, Ctr Biol Evaluat & Res, Sect Retroviral Immunol, Div Viral Prod, Bethesda, MD 20892 USA. US FDA, Ctr Biol Evaluat & Res, Cellular Immunol Lab, Div Cellular & Gene Therapies, Bethesda, MD 20892 USA. USN, Med Res Inst, Malaria Program, Bethesda, MD USA. RP Klinman, DM (reprint author), US FDA, Ctr Biol Evaluat & Res, Sect Retroviral Immunol, Div Viral Prod, Bldg 29A,Room 3 D 10 HFM 454, Bethesda, MD 20892 USA. NR 38 TC 11 Z9 11 U1 0 U2 0 PU GERONTOLOGICAL SOCIETY AMER PI WASHINGTON PA 1275 K STREET NW SUITE 350, WASHINGTON, DC 20005-4006 USA SN 1079-5006 J9 J GERONTOL A-BIOL JI J. Gerontol. Ser. A-Biol. Sci. Med. Sci. PD JUL PY 1998 VL 53 IS 4 BP B281 EP B286 PG 6 WC Geriatrics & Gerontology; Gerontology SC Geriatrics & Gerontology GA 101QR UT WOS:000074880100008 PM 18314558 ER PT J AU Steinert, SA Montee, RS Sastre, MP AF Steinert, SA Montee, RS Sastre, MP TI Influence of sunlight on DNA damage in mussels exposed to polycyclic aromatic hydrocarbons SO MARINE ENVIRONMENTAL RESEARCH LA English DT Article; Proceedings Paper CT 9th International Symposium on Responses of Marine Organisms to Pollutants (PRIMO 9) CY APR 27-30, 1997 CL BERGEN, NORWAY ID GEL-ELECTROPHORESIS ASSAY; TOXICITY AB DNA single-strand break levels were compared in mussels deployed in San Diego Bay. Mussels were deployed at two locations, a reference site and at a location known to have high concentrations of PAHs. Two vertically oriented lines of mussels Mere deployed at each location for a period of 32 days. Mussels were attached to the lines at depths of 0.3, 1 and 3 m. One line was fully exposed to ambient sunlight, the other was shaded from sunlight to examine the role of PAH light activation on the expression of DNA damage in hemocytes and whole organism growth. Damage and growth measurements were made on days 0, 5, 14, and 32. Temperatures at the stations varied only by similar to 0.5 degrees C. Hydrocarbon levels at the high PAH station were on average six times higher than the reference station. Slower growth and higher DNA damage was observed in cells from light exposed mussels at the PAH contaminated site. These effects decreased with depth. High levels of DNA damage could be induced with low intensity ultraviolet light exposure of cells from depurated or shaded mussels exposed to PAHs. DNA damage in mussels from the high impact site could be reduced to baseline levels after 24 h depuration in the dark. These results confirm previous findings showing increased DNA damage in PAH and sunlight exposed mussels. and demonstrate the significant impact of photoactivation on the health of these organisms. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Comp Sci Corp, Marine Sci Div, San Diego, CA 92110 USA. Univ Puerto Rico, Dept Biol, Humacao, PR 00791 USA. USN Command, Control Ocean Surveillance Ctr, Ocean Sci Lab, San Diego, CA 92152 USA. RP Steinert, SA (reprint author), Comp Sci Corp, Marine Sci Div, San Diego, CA 92110 USA. NR 7 TC 29 Z9 31 U1 0 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0141-1136 J9 MAR ENVIRON RES JI Mar. Environ. Res. PD JUL-DEC PY 1998 VL 46 IS 1-5 BP 355 EP 358 DI 10.1016/S0141-1136(97)00088-3 PG 4 WC Environmental Sciences; Marine & Freshwater Biology; Toxicology SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Toxicology GA 117WR UT WOS:000075806100071 ER PT J AU Kennell, C AF Kennell, C TI Design trends in high-speed transport SO MARINE TECHNOLOGY AND SNAME NEWS LA English DT Article AB This paper presents a method for analyzing transport properties of competing ship types of interest for high speed commercial transport Simple parametric relationships link requirements (speed, range, and cargo weight) to design characteristics (installed power ship weight, and fuel weight) for conventional and unconventional hull designs. These design trends are supported by data for a variety of ship types (monohull, catamaran, SES, hydrofoil, airship, ekranoplan) either currently or formerly in service. While the method is inherently general, the data selected is focused on large ships capable of transporting heavy cargos over trans-oceanic distances at speeds of 40-100 knots. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20084 USA. RP Kennell, C (reprint author), USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20084 USA. NR 3 TC 5 Z9 5 U1 0 U2 5 PU SOC NAVAL ARCH MARINE ENG PI JERSEY CITY PA 601 PAVONIA AVENUE, JERSEY CITY, NJ 07306 USA SN 0025-3316 J9 MAR TECHNOL SNAME N JI Mar. Technol. Sname News PD JUL PY 1998 VL 35 IS 3 BP 127 EP 134 PG 8 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 104PQ UT WOS:000075023300002 ER PT J AU Kennell, C Lavis, DR Templeman, MT AF Kennell, C Lavis, DR Templeman, MT TI High-speed sealift technology SO MARINE TECHNOLOGY AND SNAME NEWS LA English DT Article AB This paper describes a process that is currently being used within DoD and industry to examine the possibilities offered by technology to enhance the transport performance of high-speed commercial and military sealift. Technology projections are presented for both the near-term and the far-term. The impact of technology projections on transport performance properties is assessed both quantitatively and qualitatively. These assessments provide significant insight into the overall transport performance potential of hullforms and other technologies of interest, considerably in advance of detailed design studies. The quantitative assessment uses a derivation of the empirical method published by Kennell [1](4), which provides simple parametric relationships between mission requirements, expressed in terms of speed, range and payload, and design characteristics, expressed in terms of displacement, installed power and fuel weight, to compare the various hullforms and other technologies of interest. The qualitative assessment applies an established decision-making method to ascertain the relative capabilities and relative risks of hullforms and other technologies of interest for significant aspects of sea transport, other than speed, range and payload. While the methods used are generic, the data selected and results presented are aimed at ships capable of rapidly transporting heavy cargo over long distances. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20084 USA. RP Kennell, C (reprint author), USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20084 USA. NR 0 TC 6 Z9 6 U1 0 U2 1 PU SOC NAVAL ARCH MARINE ENG PI JERSEY CITY PA 601 PAVONIA AVENUE, JERSEY CITY, NJ 07306 USA SN 0025-3316 J9 MAR TECHNOL SNAME N JI Mar. Technol. Sname News PD JUL PY 1998 VL 35 IS 3 BP 135 EP 150 PG 16 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 104PQ UT WOS:000075023300003 ER PT J AU Sze, C Gulari, E Demczyk, BG AF Sze, C Gulari, E Demczyk, BG TI Structure of coprecipitated gold-iron oxide catalyst materials SO MATERIALS LETTERS LA English DT Article DE electron microscopy; Mossbauer spectroscopy; surface diffusion; surface energy; surface segregation; gold; iron oxide; catalyst ID TEMPERATURE CO OXIDATION; CARBON-MONOXIDE; MOSSBAUER-SPECTROSCOPY; BEHAVIOR AB Ultra-fine gold particles supported on iron oxide have been synthesized by coprecipitation and subsequently heat treated in air at temperatures of 200 degrees C and above. Structure analyses have revealed Variations in the degree of crystallinity of the iron oxide support as well as gold particle size and size distribution with heat treatment temperature. Significantly, X-ray diffraction reveals an ultra fine crystallite structure in as-prepared and lower temperature heat treated samples, while Mossbauer spectroscopy suggests the possibility of gold incorporation into the alpha-Fe2O3 phase in the lower temperature annealed samples. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Michigan, Dept Chem Engn, Ann Arbor, MI 48109 USA. RP Demczyk, BG (reprint author), USN, Naval Surface Warfare Ctr, Energet Mat Dept, Indian Head, MD 20640 USA. NR 17 TC 13 Z9 15 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-577X J9 MATER LETT JI Mater. Lett. PD JUL PY 1998 VL 36 IS 1-4 BP 11 EP 16 DI 10.1016/S0167-577X(97)00289-9 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA ZY510 UT WOS:000074629000003 ER PT J AU Fan, L Last, H Wood, R Dudley, B Malek, CK Ling, Z AF Fan, L Last, H Wood, R Dudley, B Malek, CK Ling, Z TI SLIGA based underwater weapon safety and arming system SO MICROSYSTEM TECHNOLOGIES LA English DT Article AB The Naval Surface Warfare Center, Indian Head Division (NSWCIHD) is applying microelectromechanical system (MEMS) technology to underwater weapon Safety and Arming (S&A) system development. MEMS technology provides an opportunity to develop a miniaturized S&A system that is more sophisticated with improved safety and reliability at a lower cost compared to current systems. An S&A system prevents premature initiation of the weapon while reliably ensuring initiation at the appropriate rime. An S&A system uses multiple sensors and devices. In comparison with other weapon S&A systems, a critical aspect of underwater weapon S&A systems is the mechanical interlock system utilizing actuators and mechanical sensors. This paper describes the design, development and fabrication of S&A SLIGA device prototypes and of a SLIGA based S&A system. NSWCIHD worked with members of the HI-MEMS Alliance during design, development and fabrication. Advancements achieved by the HI-MEMS Alliance and SLIGA S&A design issues are discussed. C1 USN, Ctr Surface Warfare, Indian Head Div, Indian Head, MD 20640 USA. MCNC, MEMS Technol Applicat Ctr, Res Triangle Pk, NC USA. Louisiana State Univ, CAMD, Baton Rouge, LA 70803 USA. RP Fan, L (reprint author), USN, Ctr Surface Warfare, Indian Head Div, 101 Strauss Ave,Blds 302, Indian Head, MD 20640 USA. NR 2 TC 26 Z9 26 U1 0 U2 3 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0946-7076 J9 MICROSYST TECHNOL JI Microsyst. Technol. PD JUL PY 1998 VL 4 IS 4 BP 168 EP 171 DI 10.1007/s005420050123 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Science & Technology - Other Topics; Materials Science; Physics GA 106EA UT WOS:000075115900003 ER PT J AU Krowne, CM AF Krowne, CM TI Implicit 3-D dyadic Green's function for inhomogeneous ferrite microstrip circulator with uniform surrounding and top material using mode matching SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE planar circulator; nonreciprocal media; Green's function; mode matching ID DEPOSITION; FILMS AB It is possible to combine the source constraint equations with the mode-matching technique employing mode orthogonality to encourage sparsity in subsequent matrix system development, to obtain in direct space implicit dyadic Green's function elements. This is particularly useful because field information and s-parameters may be found in real space completely avoiding typical inverse transformations. The approach allows the inclusion of uniform surrounding dielectric material as well as a cover plate above the ferrite puck.* (C) 1998 John Wiley & Sons, Inc. C1 USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Washington, DC 20375 USA. RP Krowne, CM (reprint author), USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Code 6850-3, Washington, DC 20375 USA. NR 14 TC 1 Z9 1 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 JUL PY 1998 VL 18 IS 4 BP 290 EP 296 PG 7 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA ZU808 UT WOS:000074237000013 ER PT J AU Krowne, CM AF Krowne, CM TI Reply to "Comments on 'Quantum oscillator argument against nonreciprocity in linear bi-isotropic media'" SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Editorial Material C1 USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Washington, DC 20375 USA. RP Krowne, CM (reprint author), USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Code 6850-3, Washington, DC 20375 USA. NR 1 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 JUL PY 1998 VL 18 IS 4 BP 314 EP 314 PG 1 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA ZU808 UT WOS:000074237000021 ER PT J AU Lee, RL AF Lee, RL TI The hidden costs of tobbaco smoke SO MILITARY MEDICINE LA English DT Letter C1 USN, Med Corps, Washington, DC 20350 USA. RP Lee, RL (reprint author), USN, Med Corps, Washington, DC 20350 USA. NR 0 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 JUL PY 1998 VL 163 IS 7 BP III EP III PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA 102EA UT WOS:000074910000001 PM 9695605 ER PT J AU Clarkson, CP Magann, EF Siddique, SA Morrison, JC AF Clarkson, CP Magann, EF Siddique, SA Morrison, JC TI Hematological complications of Gaucher's disease in pregnancy SO MILITARY MEDICINE LA English DT Article ID OBSTETRIC ASPECTS AB A case is presented of a 31-year-old Filipino female, gravida 5 para 2, at 38 weeks plus 5 days gestation, with known type I Gaucher's disease who underwent repeat cesarean delivery. After cesarean delivery, the patient developed disseminated intravascular coagulation and required transfusion of eight 6-packs of platelets, 6 units of fresh frozen plasma, two 10-packs of cryoprecipitate, and 6 units of packed red blood cells. pregnancy is generally well tolerated in patients with type i Gaucher's disease, an autosomal recessive lysosomal storage disorder in which lipid deposits accumulate in the liver, spleen, and bone marrow. Hemorrhagic problems secondary to severe thrombocytopenia may develop postpartum in pregnancies complicated by Gaucher's disease, requiring significant support with blood and blood products. C1 USN Hosp, Dept Obstet & Gynecol, Camp Pendleton, CA 92055 USA. RP Clarkson, CP (reprint author), USN Hosp, Dept Obstet & Gynecol, Camp Pendleton, CA 92055 USA. NR 18 TC 6 Z9 6 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 JUL PY 1998 VL 163 IS 7 BP 499 EP 501 PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA 102EA UT WOS:000074910000015 PM 9695619 ER PT J AU Freeman, RK Maxwell, JM AF Freeman, RK Maxwell, JM TI Intralobar bronchopulmonary sequestration presenting as hemoptysis: Evidence for an acquired cause SO MILITARY MEDICINE LA English DT Article ID PULMONARY SEQUESTRATION; LUNG AB A 26-year-old pregnant female was treated for an intralobar sequestration presenting as exsanguinating hemoptysis, The case brings forth strong evidence supporting an acquired rather than a congenital cause of some intralobar sequestrations, We discuss the anatomy, epidemiology, and pathogenesis of bronchopulmonary sequestrations. C1 USN, Med Ctr, Div Cardiothorac Surg, San Diego, CA 92134 USA. RP Freeman, RK (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 7 TC 1 Z9 1 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 JUL PY 1998 VL 163 IS 7 BP 502 EP 503 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 102EA UT WOS:000074910000016 PM 9695620 ER PT J AU Broughton, JQ Gilmer, GH AF Broughton, JQ Gilmer, GH TI Harmonic analysis of Lennard-Jones FCC grain boundaries SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID CRYSTAL FLUID INTERFACE; MOLECULAR-DYNAMICS; FREE-ENERGY; SURFACES; ALUMINUM; LIQUID AB We present a harmonic analysis of symmetric tilt boundaries in face-centred cubic Lennard-Jones systems with a view to finding their thermodynamic properties. These results are used to predict those which are likely candidates for interface melting at high temperature. A system is found in which the excess energy is monotonic with misorientation, but in which the excess entropies and stresses are not. The analysis shows that the presence of a grain boundary perturbs the high- and low-frequency modes by making them more localized at the boundary. Very localized split-off states outside the bulk continuum are also observed. Information on participation ratios, local densities of states and local coordination numbers helps to explain why such states exist. C1 USN, Res Lab, Complex Syst Theory, Washington, DC 20375 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Broughton, JQ (reprint author), USN, Res Lab, Complex Syst Theory, Washington, DC 20375 USA. NR 28 TC 5 Z9 5 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD JUL PY 1998 VL 6 IS 4 BP 393 EP 404 DI 10.1088/0965-0393/6/4/008 PG 12 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 121GH UT WOS:000076004600008 ER PT J AU Jacobs, KS AF Jacobs, KS TI Reducing maintenance workload through reliability-centered maintenance (RCM) SO NAVAL ENGINEERS JOURNAL LA English DT Article AB Recent work is bringing the benefits of Reliability Centered Maintenance (RCM) to the Fleet. In 1996, a one-time review of the existing scheduled maintenance program for eight MCM 1 class systems, using RCM principles, reduced their PMS labor requirements by 56%, from 1,688 man-hours per ship per year to 751. In the same year, a one-time RCM-based review for the CNO's Smart Ship Project reduced the Planned Maintenance System (PMS) labor requirements for all systems aboard USS Yorktown (CG 48) by 46%, from 46,540 man-hours per year to 25,108. Both reviews examined ships that had been in service for years. They asked three fundamental questions: Is there evidence of significant age degradation? Does the task benefit the hardware? Does the task pay for itself-that is, are the benefits from the task greater than its costs? Each review found many situations where the answer to one or more of these questions was, "No." In many cases where an answer was "no", the task was retained with a longer periodicity Other tasks were shifted from "scheduled maintenance" to "unscheduled maintenance" or were deleted outright, further reducing annual workload. The next step is to spread these benefits to the rest of the surface fleet, through the Surface Ship Maintenance Effectiveness Review (SURFMER). in the SURFMER process; each significant maintenance requirement for surface ships will be reviewed periodically by the appropriate In Service Engineering Agent (ISEA), using RCM principles. All decisions will be documented together with their rationale. The SURFMER process began in late 1996. Its first results will be implemented in October 1997. C1 USN, Sea Syst Commands Surface Ship Maintenance Div, Washington, DC 20350 USA. RP Jacobs, KS (reprint author), USN, Sea Syst Commands Surface Ship Maintenance Div, SEA 915, Washington, DC 20350 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 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 JUL PY 1998 VL 110 IS 4 BP 89 EP 97 PG 9 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA 129HP UT WOS:000076458000007 ER PT J AU Kriebel, DL AF Kriebel, DL TI Nonlinear wave interaction with a vertical circular cylinder: Wave forces SO OCEAN ENGINEERING LA English DT Article ID DIFFRACTION AB Second-order wave forces on a large diameter vertical circular cylinder, computed according to a semi-analytic nonlinear diffraction theory, are compared to results of 22 laboratory experiments with regular waves. In general, predicted forces agree quite well with measured forces. In most tests, both measured and predicted maximum forces exceeded linear theory by 5 to 15%. In a few cases, however, the measured forces were less than those predicted by linear theory, in contrast to the second-order predictions. It is shown that these results are related to the phasing of various linear and nonlinear wave force components, and are consistent with those obtained by other investigators. Published by Elsevier Science Ltd. C1 USN Acad, Ocean Engn Program, Annapolis, MD 21402 USA. RP Kriebel, DL (reprint author), USN Acad, Ocean Engn Program, Annapolis, MD 21402 USA. NR 10 TC 13 Z9 18 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0029-8018 J9 OCEAN ENG JI Ocean Eng. PD JUL PY 1998 VL 25 IS 7 BP 597 EP 605 DI 10.1016/S0029-8018(97)00029-2 PG 9 WC Engineering, Marine; Engineering, Civil; Engineering, Ocean; Oceanography SC Engineering; Oceanography GA ZB834 UT WOS:000072512700008 ER PT J AU Beadie, G Rabinovich, WS Sanghera, J Aggarwal, I AF Beadie, G Rabinovich, WS Sanghera, J Aggarwal, I TI Fabrication of microlenses in bulk chalcogenide glass SO OPTICS COMMUNICATIONS LA English DT Article DE laser assisted thermal runaway; microlenses; chalcogenide glass ID AS2S3 GLASS; PHOTOEXPANSION AB A new method for fabricating microlenses in bulk, glassy Ge,,Se,, is demonstrated, Based upon a laser-induced thermal runaway effect, the process has been used to fabricate lenses with diameters between 70 and 180 mu m and numerical apertures of about 0.4. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Beadie, G (reprint author), USN, Res Lab, Code 5642,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 12 TC 17 Z9 17 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD JUL 1 PY 1998 VL 152 IS 4-6 BP 215 EP 220 DI 10.1016/S0030-4018(98)00172-2 PG 6 WC Optics SC Optics GA 103JR UT WOS:000075154200001 ER PT J AU Goldberg, L Koplow, JP Moeller, RP Kliner, DAV AF Goldberg, L Koplow, JP Moeller, RP Kliner, DAV TI High-power superfluorescent source with a side-pumped Yb-doped double-cladding fiber SO OPTICS LETTERS LA English DT Article ID AMPLIFIER AB A compact superfluorescent source based on an Yb-doped double-cladding fiber amplifier is described. The packaged amplifier is pumped at 975 nm by side-coupling emission from a 2.0-W broad-stripe laser diode through an imbedded V groove. The fiber source generates 485 mW of broadband emission centered at 1055 nm with a 41-nm FWHM flat power spectrum. OCIS codes: 160.6630, 160.3510, 140.4480, 060.2380, 060.2320, 060.2310. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Goldberg, L (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 14 TC 49 Z9 54 U1 1 U2 4 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 JUL 1 PY 1998 VL 23 IS 13 BP 1037 EP 1039 DI 10.1364/OL.23.001037 PG 3 WC Optics SC Optics GA ZY167 UT WOS:000074593000019 PM 18087421 ER PT J AU Yencha, MW AF Yencha, MW TI Allergic fungal sinusitis: Immunotherapy as part of the treatment plan SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Letter C1 USN Hosp, FPO, AP 96350 USA. RP Yencha, MW (reprint author), USN Hosp, PSC 475,Box 1604, FPO, AP 96350 USA. NR 0 TC 0 Z9 0 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 JUL PY 1998 VL 119 IS 1 BP 149 EP 149 PG 1 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA 100NQ UT WOS:000074822600029 PM 9674533 ER PT J AU Martin, WR Fuller, RE AF Martin, WR Fuller, RE TI Suspected chromium picolinate-induced rhabdomyolysis SO PHARMACOTHERAPY LA English DT Article ID EXERCISE AB Rhabdomyolysis results from skeletal muscle injury and release of muscle cell contents into plasma. A number of etiologic factors have been reported for the condition, including strenuous exercise, weight lifting, trauma, seizure, sepsis, and alcohol and drug abuse. Hundreds of drugs also reportedly cause rhabdomyolysis. A 24-year-old body builder developed the disease after ingesting 1200 mu g of chromium picolinate (6-24 times the daily recommended allowance of 50-200 mu g) over 48 hours. We believe this to be the first reported case of chromium-induced rhabdomyolysis. C1 USN, Dept Pharm, Natl Naval Med Ctr, Bethesda, MD 20889 USA. Univ Arkansas Med Sci, Coll Pharm, Little Rock, AR 72205 USA. RP Fuller, RE (reprint author), USN, Dept Pharm, Natl Naval Med Ctr, Bethesda, MD 20889 USA. NR 11 TC 46 Z9 46 U1 1 U2 1 PU PHARMACOTHERAPY PUBLICATIONS INC PI BOSTON PA NEW ENGLAND MEDICAL CENTER BOX 806 171 HARRISON AVE, BOSTON, MA 02111 USA SN 0277-0008 J9 PHARMACOTHERAPY JI Pharmacotherapy PD JUL-AUG PY 1998 VL 18 IS 4 BP 860 EP 862 PG 3 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 110TA UT WOS:000075395400021 PM 9692662 ER PT J AU Ashton, EA Schaum, A AF Ashton, EA Schaum, A TI Algorithms for the detection of sub-pixel targets in multispectral imagery SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article AB A new sub-pixel target detection algorithm is developed that integrates a linear mixing model (LMM) with the powerful "RX" anomaly detector of Reed and Yu (1990). RX is applied to mixing model errors instead of to measured radiances, because they are more nearly multivariate Gaussian. The integrated method consistently outperforms spectral anomaly detectors that are based on either ax or an LMM alone. A novel method of image-based endmember selection is also presented, and a simple method of computing the fully constrained LMM residuals is described. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ashton, EA (reprint author), USN, Res Lab, Code 5621,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 14 TC 40 Z9 44 U1 1 U2 3 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 USA SN 0099-1112 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD JUL PY 1998 VL 64 IS 7 BP 723 EP 731 PG 9 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA ZY268 UT WOS:000074603100006 ER PT J AU Knipp, PA Reinecke, TL AF Knipp, PA Reinecke, TL TI Boundary-element calculations of electromagnetic band-structure of photonic crystals SO PHYSICA E LA English DT Article; Proceedings Paper CT 8th International Conference on Modulated Semiconductor Structures CY JUL 14-18, 1997 CL UNIV CA, SANTA BARBARA, CALIFORNIA HO UNIV CA DE photonic crystal; electromagnetic band-structure; bandgap; dielectric materials AB A boundary element method is developed for calculating the photon modes of periodic structures whose unit cells consist of piecewise homogeneous dielectric materials of arbitrary shapes. Green's function techniques are used to derive integral equations for these structures. These equations involve integrals over the boundaries between the regions, which are discretized and solved numerically. Thus the full set of Maxwell's equations with boundary conditions in d independent variables is changed into an integral equation in d - 1 variables. This allows for the calculation of mode frequencies and field patterns for wave vectors throughout the Brillouin zone, thus allowing the determination of photonic band gaps. An illustrative example is given here for a two-dimensional system. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Christopher Newport Univ, Newport News, VA 23606 USA. USN, Res Lab, Washington, DC 20375 USA. RP Knipp, PA (reprint author), Christopher Newport Univ, Newport News, VA 23606 USA. NR 8 TC 20 Z9 20 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1386-9477 J9 PHYSICA E JI Physica E PD JUL PY 1998 VL 2 IS 1-4 BP 920 EP 924 DI 10.1016/S1386-9477(98)00187-8 PG 5 WC Nanoscience & Nanotechnology; Physics, Condensed Matter SC Science & Technology - Other Topics; Physics GA 110LT UT WOS:000075383500188 ER PT J AU Ashman, C Khanna, SN Pederson, MR Porezag, DV AF Ashman, C Khanna, SN Pederson, MR Porezag, DV TI Thermal isomerization in Cs4Cl3- SO PHYSICAL REVIEW A LA English DT Article ID GENERALIZED GRADIENT APPROXIMATION; STRUCTURAL ISOMERISM; NIOBIUM CLUSTERS; HALIDE CLUSTERS AB Theoretical electronic structure studies have been carried out to show that the recently observed thermal isomerization in Cs4Cl3- clusters is due to three energetically close structures with a cuboid, a ladder, and an octagonal ring arrangement. It is found that the electronic excited states can serve as a fingerprint for identification of these structures. By calculating total energies and electronic excited states, we identify the cuboid as the most stable geometry. The vibrational spectra of the isomers are shown to be marked by low-energy modes which enable them to isomerize at ordinary temperatures. C1 Virginia Commonwealth Univ, Dept Phys, Richmond, VA 23284 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Virginia Commonwealth Univ, Dept Phys, Richmond, VA 23284 USA. NR 24 TC 6 Z9 6 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 EI 1094-1622 J9 PHYS REV A JI Phys. Rev. A PD JUL PY 1998 VL 58 IS 1 BP 744 EP 747 DI 10.1103/PhysRevA.58.744 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZZ998 UT WOS:000074790500100 ER PT J AU Chirita, M Robins, G Stamps, RL Sooryakumar, R Filipkowski, ME Gutierrez, CJ Prinz, GA AF Chirita, M Robins, G Stamps, RL Sooryakumar, R Filipkowski, ME Gutierrez, CJ Prinz, GA TI Brillouin light scattering study of magnetic coupling in CoFe/Mn/CoFe SO PHYSICAL REVIEW B LA English DT Article ID EXCHANGE; ANISOTROPIES; BILAYERS AB Coupling mechanisms between Co0.75Fe0.25 films separated by Mn layers are investigated using Brillouin light scattering from thermal spin waves. Trilayers of CoFe/Mn/CoFe, grown by molecular-beam epitaxy, were studied with Mn thicknesses between 6 and 30 Angstrom. Spin-wave excitations corresponding to acoustic and optic modes in double layer magnetic structures were observed, and allowed a determination of a strong magnetic coupling between the CoFe films. Spin-wave frequencies were examined as functions of applied field, Mn film thickness, and temperature. A microscopic model is used to examine magnetic order in a ferromagnet/antiferromagnet/ferromagnet structure. Discrepancies between the data and predictions of the microscopic model provide evidence for a twist in the FeCo spins that extends into the ferromagnet layer. [S0163-1829(98)10117-0]. C1 Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Arkansas, Dept Phys, Fayetteville, AR 72701 USA. SW Texas State Univ, Dept Phys, San Marcos, TX 78666 USA. USN, Res Lab, Washington, DC 20375 USA. RP Chirita, M (reprint author), Ohio State Univ, Dept Phys, 174 W 18Th Ave, Columbus, OH 43210 USA. RI Stamps, Robert/E-7304-2011 OI Stamps, Robert/0000-0003-0713-4864 NR 11 TC 12 Z9 12 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 JUL 1 PY 1998 VL 58 IS 2 BP 869 EP 876 DI 10.1103/PhysRevB.58.869 PG 8 WC Physics, Condensed Matter SC Physics GA ZZ014 UT WOS:000074686600049 ER PT J AU Pecora, LM AF Pecora, LM TI Synchronization conditions and desynchronizing patterns in coupled limit-cycle and chaotic systems SO PHYSICAL REVIEW E LA English DT Article ID DYNAMICAL-SYSTEMS; SPATIOTEMPORAL CHAOS; JOSEPHSON-JUNCTIONS; OSCILLATOR-SYSTEMS; RIDDLED BASINS; DOUBLE SCROLL; STABILITY; ARRAYS; BIFURCATIONS; TRANSITION AB Many coupling schemes for both limit-cycle and chaotic systems involve adding linear combinations of dynamical variables from various oscillators in an array of identical oscillators to each oscillator node of the array. Examples of such couplings are (nearest neighbor) diffusive coupling, all-to-all coupling, star coupling, and random linear couplings. We show that for a given oscillator type and a given choice of oscillator variables to use in the coupling arrangement, the stability of each linear coupling scheme can be calculated from the stability of any other for symmetric coupling schemes. In particular, when there are desynchronization bifurcations our approach reveals interesting patterns and relations between desynchronous modes, including the situation in which for some systems there is a limit on the number of oscillators that can be coupled and still retain synchronous chaotic behavior. C1 USN, Res Lab, Washington, DC 20375 USA. RP Pecora, LM (reprint author), USN, Res Lab, Code 6343, Washington, DC 20375 USA. NR 72 TC 135 Z9 140 U1 3 U2 11 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 JUL PY 1998 VL 58 IS 1 BP 347 EP 360 DI 10.1103/PhysRevE.58.347 PG 14 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 101XL UT WOS:000074893400049 ER PT J AU Reed, WJ AF Reed, WJ TI Near-drowning - Life-saving steps SO PHYSICIAN AND SPORTSMEDICINE LA English DT Article ID FRESH-WATER; EMERGENCY; SEA AB Cervical-spine injury, trauma, and hypothermia should be considered in all sports-related near-drownings. The focus of resuscitation should be on prompt restoration of respiration, CPR, and advanced cardiac life support with cervical-spine precautions. A subset of near-drowning victims can be discharged after only 4 to 6 hours of observation. Although total drowning deaths have decreased 45% in the past 15 years, a greater emphasis on public education to prevent drowning remains in order. C1 USN, Med Ctr, Dept Emergency Med, San Diego, CA 92134 USA. Western Washington Univ, Bellingham, WA 98225 USA. RP Reed, WJ (reprint author), USN, Med Ctr, Dept Emergency Med, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 20 TC 0 Z9 0 U1 0 U2 0 PU MCGRAW HILL HEALTHCARE PUBLICATIONS PI MINNEAPOLIS PA 4530 WEST 77TH ST, MINNEAPOLIS, MN 55435-5000 USA SN 0091-3847 J9 PHYSICIAN SPORTSMED JI Physician Sportsmed. PD JUL PY 1998 VL 26 IS 7 BP 31 EP 36 PG 6 WC Primary Health Care; Orthopedics; Sport Sciences SC General & Internal Medicine; Orthopedics; Sport Sciences GA 100KL UT WOS:000074815200016 PM 20086831 ER PT J AU Reynolds, MA Ganguli, G AF Reynolds, MA Ganguli, G TI Ion Bernstein waves driven by two transverse flow layers SO PHYSICS OF PLASMAS LA English DT Article ID QUANTUM WELLS; EIGENVALUES; INSTABILITY AB The interaction between two narrow layers of EXB flow is investigated, along with their stability properties. The mode frequencies, growth rates, and eigenfunctions are calculated. It is found that the instability due to a single layer is robust to the inclusion of a second layer. Specifically, when the separation between the layers is on the order of the ion-cyclotron radius, there is strong coupling between the two layers and the second layer is destabilizing. In addition, when the flow velocities are in opposite directions a wide variety of modes is possible, including near-zero-frequency modes, resulting in broadband structure in both the frequency spectrum and the wave number spectrum. These results may have implications for the understanding of the auroral ionosphere, where such spatial structure in the transverse electric field is often observed. (C) 1998 American Institute of Physics. [S1070-664X(98)03807-5] C1 USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. RP Reynolds, MA (reprint author), USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. EM anthony@ppdu.nrl.navy.mil NR 21 TC 9 Z9 10 U1 0 U2 3 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 JUL PY 1998 VL 5 IS 7 BP 2504 EP 2512 DI 10.1063/1.872934 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 110KR UT WOS:000075380400006 ER PT J AU Klinker, E Rabier, F Gelaro, R AF Klinker, E Rabier, F Gelaro, R TI Estimation of key analysis errors using the adjoint technique SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE forecast error growth; numerical weather prediction ID SENSITIVITY; PREDICTABILITY; MODEL AB An iteration procedure minimizing the short-range forecast error leads, after some iterations, to so-called key analysis errors. These are estimates of the part of analysis errors that is largely responsible for the short-range forecast errors. The first step of the minimization procedure provides a scaled gradient of the two-day forecast errors for which the 'energy' inner-product provides an efficient way of identifying the analysis errors at scales that are relevant for forecast error growth. By using an 'enstrophy' Like inner-product as an alternative to 'energy' the sensitivity gradient obtains an unrealistically large scale. Performing a few more steps in the minimization provides better estimates of the analysis error in the directions spanned by the leading singular vectors of the tangent-linear model. On a case study it is shown that three steps provide key analysis increments which, when added to the analysis, both significantly improve the fit to the available data and substantially improve the subsequent model integration. It does not appear to be beneficial to do more steps of the minimization because of the uncertainty in the definition of the short-range forecast error, and of approximations in the tangent-linear model. Key analysis errors represent an improved estimate of analysis errors compared to the scaled gradient of day-2 forecast errors. In particular the geographical distribution shows the stability dependence of the scaled gradient. The projection of the gradient on the fastest growing errors limits maximum sensitivity to the major baroclinic zones. The close correspondence of evolved key analysis errors and forecast errors shows that key analysis errors are more realistically projecting on to full analysis errors. The close link between the stability of the flow and the gradient of the forecast errors implies an unreasonably strong seasonal variation of analysis errors estimates. In contrast, key analysis errors are nearly seasonally independent, which means that their detrimental effect on forecast errors in absolute terms in summer and winter is comparable. C1 European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England. USN, Res Lab, Monterey, CA USA. RP Klinker, E (reprint author), European Ctr Medium Range Weather Forecasts, Shinfield Pk, Reading RG2 9AX, Berks, England. NR 22 TC 49 Z9 51 U1 1 U2 1 PU ROYAL METEOROLOGICAL SOC PI READING PA 104 OXFORD ROAD, READING, BERKS, ENGLAND RG1 7LJ SN 0035-9009 J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD JUL PY 1998 VL 124 IS 550 BP 1909 EP 1933 PN B PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 117BB UT WOS:000075759000006 ER PT J AU Headrick, JM Thomason, JF AF Headrick, JM Thomason, JF TI Applications of high-frequency radar SO RADIO SCIENCE LA English DT Article AB Efforts to extend radar range by an order of magnitude with use of the ionosphere as a virtual mirror started after the end of World War II. A number of HF radar programs were pursued, with long-range nuclear burst and missile launch detection demonstrated by 1956. Successful east coast radar aircraft defect and track tests extending across the Atlantic were conducted by 1961. The major obstacles to success, the large target-to-clutter ratio and low signal-to-noise ratio, were overcome with matched filter Doppler processing. To search the areas that a 2000 nautical mile (3700 km) radar can reach, very complex and high dynamic range processing is required. The spectacular advances in digital processing technology have made truly wide-area surveillance possible. Use of the surface attached wave over the oceans can enable HF radar to obtain modest extension of range beyond the horizon. The decameter wavelengths used by both skywave and surface wave radars require large physical antenna apertures, but they have unique capabilities for air and surface targets, many of which are of resonant scattering dimensions. Resonant scattering from the ocean permits sea state and direction estimation. Military and commercial applications of HF radar are in their infancy. C1 USN, Res Lab, Washington, DC 20375 USA. RP Headrick, JM (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. EM headrick@radar.nrl.navy.mil; thomason@radar.nrl.navy.mil NR 21 TC 46 Z9 61 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JUL-AUG PY 1998 VL 33 IS 4 BP 1045 EP 1054 DI 10.1029/98RS01013 PG 10 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 105RZ UT WOS:000075088500022 ER PT J AU Root, BT AF Root, BT TI HF-over-the-horizon radar ship detection with short dwells using clutter cancelation SO RADIO SCIENCE LA English DT Article ID FREQUENCY AB Coherent sea-clutter cancelation is shown to be an effective method for the exposure of ships with HF OTH (high-frequency over-the-horizon) sky wave radar. A sinusoidal model has been successfully used to approximate and subtract the first-order Bragg peaks, which spread and mask slow targets when using Fourier Doppler processing on short dwells (fewer than 10 s). (Short dwells are required for aircraft surveillance over the vast HF radar coverage area) The new clutter canceling algorithm has been successfully applied to both synthetic and real OTH data from the U.S. Navy's Relocatable Over-the-Horizon radar (ROTHR) (AN/TPS-71), and results are presented. C1 USN, Res Lab, Div Radar, Washington, DC 20375 USA. RP Root, BT (reprint author), USN, Res Lab, Div Radar, Code 5324 Radar,4555 Overlook Ave SW, Washington, DC 20375 USA. EM benroot@radar.nrl.navy.mil NR 28 TC 26 Z9 37 U1 0 U2 2 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 JUL-AUG PY 1998 VL 33 IS 4 BP 1095 EP 1111 DI 10.1029/98RS01313 PG 17 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 105RZ UT WOS:000075088500026 ER PT J AU Maia, D Pick, M Kerdraon, A Howard, R Brueckner, GE Michels, DJ Paswaters, S Schwenn, R Lamy, P Llebaria, A Simnett, G Aurass, H AF Maia, D Pick, M Kerdraon, A Howard, R Brueckner, GE Michels, DJ Paswaters, S Schwenn, R Lamy, P Llebaria, A Simnett, G Aurass, H TI Joint Nancay radioheliograph and LASCO observations of coronal mass ejections - I. The 1 July 1996 event SO SOLAR PHYSICS LA English DT Article ID III BURST SOURCES AB The development of a coronal mass ejection on 1 July 1996 has been analyzed by comparing the observations of the LASCO/SOHO coronagraph with those of the Nancay radioheliograph. This comparison brings new insight and very useful diagnosis for the study of CME events. It is shown that the initial instability took place in a small volume located above an active region and that the occurrence of short radio type III bursts implies a triggering process due to magnetic field interactions. The subsequent spatial and temporal evolution of the radio emission strongly suggests that the large scale structure becomes unstable within the first minute of the event. C1 Observ Meudon, DASOP, CNRS, URA 2080, F-92195 Meudon, France. USN, Res Lab, Washington, DC 20375 USA. Max Planck Inst Aeron, Lindau, Germany. CNRS, Astron Spatiale Lab, F-13012 Marseille, France. Univ Birmingham, Sch Phys & Space Res, Space Res Grp, Birmingham B15 2TT, W Midlands, England. Inst Astrophys, Potsdam, Germany. Univ Lisbon, Fac Ciencias, P-1699 Lisbon, Portugal. RP Maia, D (reprint author), Observ Meudon, DASOP, CNRS, URA 2080, F-92195 Meudon, France. OI Maia, Dalmiro/0000-0001-7855-1919 NR 9 TC 15 Z9 15 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 JUL PY 1998 VL 181 IS 1 BP 121 EP 132 DI 10.1023/A:1005012907738 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 113KL UT WOS:000075550100010 ER PT J AU Dryer, M Andrews, MD Aurass, H Deforest, C Galvin, AB Garcia, H Ipavich, FM Karlicky, M Kiplinger, A Klassen, A Meisner, R Paswaters, SE Smith, Z Tappin, SJ Thompson, BJ Watari, SI Michels, DJ Brueckner, GE Howard, RA Koomen, MJ Lamy, P Mann, G Arzner, K Schwenn, R AF Dryer, M Andrews, MD Aurass, H Deforest, C Galvin, AB Garcia, H Ipavich, FM Karlicky, M Kiplinger, A Klassen, A Meisner, R Paswaters, SE Smith, Z Tappin, SJ Thompson, BJ Watari, SI Michels, DJ Brueckner, GE Howard, RA Koomen, MJ Lamy, P Mann, G Arzner, K Schwenn, R TI The solar minimum active region 7978, its X2.6/1B flare, CME, and interplanetary shock propagation of 9 July 1996 SO SOLAR PHYSICS LA English DT Article ID CORONAL MASS EJECTIONS; MAGNETOHYDRODYNAMIC SIMULATION; DYNAMICAL EVOLUTION; SCINTILLATION; STREAMER; SYSTEM; IPS AB The first X-class flare in four years occurred on 9 July 1996. This X2.6/LB flare reached its maximum at 09:11 UT and was located in active region 7978 (S10 degrees W30 degrees) which was an old-cycle sunspot polarity group. We report the SOHO LASCO/EIT/MDI and SOONSPOT observations before and after this event together with Yohkoh SXT images of the flare, radio observations of the type II shock, and GOES disk-integrated soft X-ray flux during an extended period that included energy build-up in this active region. The LASCO coronagraphs measured a significant coronal mass ejection (CME) on the solar west limb beginning on 8 July at about 09:53 UT. The GOES 8 soft X-ray Aux (0.1-0.8 nm) had started to increase on the previous day from below the A-level background (10(-8) W m(-2)). At the start time of the CME, it was at the mid-B level and continued to climb. This CME is similar to many events which have been seen by LASCO and which are being interpreted as disruption of existing streamers by emerging flux ropes. LASCO and EIT were not collecting data at the time of the X-flare due to a temporary software outage. A larger CME was in progress when the first LASCO images were taken after the flare, Since the first image of the 'big' CME was obtained after the flare's start time, we cannot clearly demonstrate the physical connection of the CME to the flare. However, the LASCO CME data are consistent with an association of the flare and the CME. No eruptive filaments were observed during this event. We used the flare evidence noted above to employ in real time 3 simplified Shock-Time-of-Arrival (STOA) algorithm to estimate the arrival of a weak shock at the WIND spacecraft. We compare this prediction with the plasma and IMF data from WIND and plasma data from the SOHO/CELIAS instrument and suggest that the flare - and possibly the interplanetary consequences of the 'big' CME - was the progenitor of the mild, high-latitude, geomagnetic storm (daily sum of K p = 16+, Ap = 8) on 12 July 1996. We speculate that the shock was attenuated enroute to Earth as a result of interaction with the heliospheric current/plasma sheer. C1 NOAA, Space Environm Ctr, Boulder, CO 80303 USA. Hughes STX NRL, Washington, DC 20375 USA. Inst Astrophys, D-14472 Potsdam, Germany. Stanford Univ, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Colorado, Boulder, CO 80309 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Birmingham, Birmingham B15 275, W Midlands, England. NASA, Space Applicat Corp, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Commun Res Lab, Tokyo 184, Japan. Astron Spatiale Lab, F-13376 Marseille 12, France. Max Planck Inst Aeron, D-37189 Katlenburg Lindau, Germany. Univ Maryland, College Pk, MD 20742 USA. Astron Inst, Ondrejov Observ, Ondrejov, Czech Republic. Univ Bern, Inst Angew Phys, CH-3012 Bern, Switzerland. Univ Colorado, Denver, CO 80201 USA. SFA Inc, Landover, MD 20785 USA. RP Dryer, M (reprint author), NOAA, Space Environm Ctr, Boulder, CO 80303 USA. RI Galvin, Antoinette/A-6114-2013; Thompson, Barbara/C-9429-2012; Karlicky, Marian/G-9023-2014; xue, yansheng/A-9712-2012 NR 35 TC 33 Z9 33 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 JUL PY 1998 VL 181 IS 1 BP 159 EP 183 DI 10.1023/A:1016522812668 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 113KL UT WOS:000075550100012 ER PT J AU Mehay, SL Hogan, PF AF Mehay, SL Hogan, PF TI The effect of separation bonuses on voluntary quits: Evidence from the military's downsizing SO SOUTHERN ECONOMIC JOURNAL LA English DT Article ID RETIREMENT AB This paper analyzes the decision of mid-career personnel to voluntarily leave the U.S. military in response to a financial incentive program. A model of the separation decision is tested using data on Navy and Air Force enlisted personnel who were targeted for the buyout in 1992. Two alternative estimates are provided, one from a fixed effects model and one from a structural, annualized cost of leaving model. Our basic results indicate the financial incentive had a modest effect in inducing additional quits. The impact of the separation bonus, however, was much larger for occupations facing a threat of involuntary layoff. C1 USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93943 USA. Lewin Grp, Fairfax, VA 22031 USA. Stanford Univ, Hoover Inst, Stanford, CA 94305 USA. RP Mehay, SL (reprint author), USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93943 USA. EM smehay@nps.navy.mil NR 17 TC 5 Z9 5 U1 0 U2 1 PU UNIV NORTH CAROLINA PI CHAPEL HILL PA SOUTHERN ECONOMIC JOURNAL, CHAPEL HILL, NC 27514 USA SN 0038-4038 J9 SOUTHERN ECON J JI South. Econ. J. PD JUL PY 1998 VL 65 IS 1 BP 127 EP 139 DI 10.2307/1061356 PG 13 WC Economics SC Business & Economics GA 102CQ UT WOS:000074906000008 ER PT J AU McCafferty, E Wightman, JP AF McCafferty, E Wightman, JP TI Determination of the concentration of surface hydroxyl groups on metal oxide films by a quantitative XPS method SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE XPS; x-ray photoelectron spectroscopy; angle-resolved; Al; hydroxyl ID RAY PHOTOELECTRON-SPECTROSCOPY; ACID-BASE PROPERTIES; STAINLESS-STEEL; UPS EXAMINATIONS; PASSIVE LAYERS; ALUMINUM; IRON; ALLOYS; HYDRATION; ADHESION AB Quantitative XPS has been used to determine the surface concentration of hydroxyl groups in native air-formed oxide films on metals having low surface areas. A mathematical expression has been derived to give the concentration of surface hydroxyl groups as a function of the intensity ratio of the OH to O2- contributions to the O 1s photopeak. This expression is based on modeling the oxide film on a metal to be a multilayer system consisting of an outermost layer of organic contamination, a layer of chemisorbed water, a surface hydroxylated region of tbe oxide film and the inner portion of the oxide film; The average values of the experimentally determined concentrations of surface hydroxyl groups are 15, 13, 11, 6 and 8 OH nm(-2) for oxide-covered aluminum, chromium, titanium, tantalum and silicon, respectively. X-ray photoelectron spectroscopy depth profiles using argon ion sputtering and variable-angle XPS have been utilized in this work. Surface treatments have employed-either ultrasonic cleaning with organic solvents or argon plasma treatment. (C) 1998 John Wiley & Sons, Ltd. C1 Virginia Polytech Inst & State Univ, Dept Chem, Ctr Adhes & Sealant Sci, Blacksburg, VA 24061 USA. RP McCafferty, E (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 73 TC 399 Z9 404 U1 34 U2 232 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD JUL PY 1998 VL 26 IS 8 BP 549 EP 564 DI 10.1002/(SICI)1096-9918(199807)26:8<549::AID-SIA396>3.0.CO;2-Q PG 16 WC Chemistry, Physical SC Chemistry GA 103KJ UT WOS:000075000000002 ER PT J AU Hurley, CK Steiner, N Kosman, C Mitton, W Koester, R Bei, M Bush, J McCormack, J Hahn, A Henson, V Hoyer, R Wade, JA Hartzman, RJ Ng, J AF Hurley, CK Steiner, N Kosman, C Mitton, W Koester, R Bei, M Bush, J McCormack, J Hahn, A Henson, V Hoyer, R Wade, JA Hartzman, RJ Ng, J TI Novel HLA-A and HLA-B alleles SO TISSUE ANTIGENS LA English DT Article DE HLA-A; HLA-B; polymorphism ID SEQUENCES; LOCUS AB Nine novel HLA-A and HLA-B alleles are described: A*2609, A*6803, A*6806, B*1539, B*1540, B*2712, B*4103, B*5109, and B*5603. Most appear to have arisen by gene conversion events. B*5603 appears to have arisen by a reciprocal recombination event joining exon 2 of a B*55/*56 allele with exon 3 of a B*15 allele. Seroiogically, the antigen encoded by this allele types with broad B22- and Bw6-specific alloantisera. Also unique, the antigen encoded by B*2712 does not react with B27-specific alloantisera but does react with Bw6-specific alloantisera. C1 Georgetown Univ, Sch Med, Dept Microbiol & Immunol, Washington, DC USA. USN, Med Res Inst, Bethesda, MD USA. Lab Corp Amer Holdings, Burlington, NC USA. Georgetown Univ, Sch Med, Dept Pediat, Washington, DC 20007 USA. Baylor Univ, Med Ctr, Dallas, TX USA. Albany Med Coll, Albany, NY 12208 USA. Univ Toronto, Toronto Hosp, Reg Histocompatibil Lab, Toronto, ON M5G 2M1, Canada. RP Hurley, CK (reprint author), Georgetown Univ, Med Ctr, E404 Res Bldg,3970 Reservoir Rd NW, Washington, DC 20007 USA. NR 13 TC 14 Z9 15 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0001-2815 J9 TISSUE ANTIGENS JI Tissue Antigens PD JUL PY 1998 VL 52 IS 1 BP 84 EP 87 DI 10.1111/j.1399-0039.1998.tb03029.x PG 4 WC Cell Biology; Immunology; Pathology SC Cell Biology; Immunology; Pathology GA 102ZL UT WOS:000074956100013 PM 9714480 ER PT J AU Reboulet, JE Kimmel, EC Carpenter, RL AF Reboulet, JE Kimmel, EC Carpenter, RL TI A basic computer program for rapid standard gas bag calculations SO TOXICOLOGY METHODS LA English DT Article DE calibration curve; inhalation toxicology; program; standard bags AB The preparation of standard gas bags containing known. volumes of toxicant and diluting gas is commonly used for the calibration of analytical instrumentation in inhalation toxicology. When the toxicant is a gas, the volume to volume calculations are readily made. However liquid toxicants require mathematical conversion from the Liquid to the gaseous state, taking into account the volume of liquid used its purity, and the effects of temperature and atmospheric pressure on the calculation of the final volume of the toxicant. The Microsoft Visual Basic program described herein accounts for all of these parameters and allows for fast, accurate computations of any one of the parameters-total volume of gas in the standard bag, parts per million of toxicant in the standard bag, microliters of toxicant required-given the other two. Since it is a menu-driven program, changes can, be readily made to the input parameters and updated values can be rapidly calculated. The program makes "what if" types of calculations extremely easy, and allows for rapid generation of data for calibration curves. C1 USN, Med Res Inst Detachment Toxicol, NMRI TD, Wright Patterson AFB, OH 45433 USA. Geo Ctr Inc, Newton Crt, MA USA. RP Reboulet, JE (reprint author), USN, Med Res Inst Detachment Toxicol, NMRI TD, Bldg 433,Area B, Wright Patterson AFB, OH 45433 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 1051-7235 J9 TOXICOL METHOD JI Toxicol. Method. PD JUL-SEP PY 1998 VL 8 IS 3 BP 165 EP 173 PG 9 WC Toxicology SC Toxicology GA 122CN UT WOS:000076053400001 ER PT J AU Casleton, BG Salata, K Dasch, GA Strickman, D Kelly, DJ AF Casleton, BG Salata, K Dasch, GA Strickman, D Kelly, DJ TI Recovery and viability of Orientia tsutsugamushi from packed red cells and the danger of acquiring scrub typhus from blood transfusion SO TRANSFUSION LA English DT Article ID POLYMERASE CHAIN-REACTION; RICKETTSIA-TSUTSUGAMUSHI; EHRLICHIOSIS; INFECTIONS; ANTIBODIES; MICE; GENE AB BACKGROUND: The purpose of this study was to determine whether infective Orientia tsutsugamushi, the etiologic agent of scrub typhus, could survive normal blood banking processing and storage procedures. STUDY DESIGN AND METHODS: Mononuclear cells isolated from whole blood by density gradient centrifugation were inoculated with O. tsutsugamushi, Karp strain. Infection of the mononuclear cells was confirmed by Giemsa stain, direct fluorescent antibody assay, and polymerase chain reaction using primers specific for the groESL operon of O. tsutsogamushi.The quantity of rickettsia[ particles in each preparation was determined by direct counts from the Giemsa-stained preparations. Infected mononuclear cells were returned to their respective aliquots of packed red blood cells, which were then either stored at 4 degrees C or glycerolized and frozen at -70 degrees C. RESULTS: Rickettsiae survived up to 10 days (but not 30 days) of refrigerated storage and 45 days of frozen storage, as determined by inoculation of mice with 0.5-mL aliquots of the blood components. Infection of the mice was determined by illness, death, direct fluorescent antibody assay of peritoneal smears, polymerase chain reaction of blood, and enzyme-linked immunosorbent assay detection of antibodies in plasma. CONCLUSION: Because the quantity of rickettsiae injected into the mice was comparable to the quantity reported in the literature for human blood during natural infections, scrub typhus could present a risk in blood collected from donors in endemic areas. This may especially be true, because people can be rickettsemic before illness, after successful antibiotic treatment, and chronically after resolution of disease. C1 Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Dept Rickettsial Dis, Washington, DC 20307 USA. Walter Reed Army Med Ctr, Dept Clin Invest, Res Operat Serv, Washington, DC 20307 USA. USN, Med Res Inst, Viral & Rickettsial Dis Program, Bethesda, MD USA. RP Kelly, DJ (reprint author), Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Dept Rickettsial Dis, Washington, DC 20307 USA. NR 50 TC 15 Z9 15 U1 0 U2 1 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD JUL PY 1998 VL 38 IS 7 BP 680 EP 689 DI 10.1046/j.1537-2995.1998.38798346638.x PG 10 WC Hematology SC Hematology GA 102ZN UT WOS:000074956300011 PM 9683108 ER PT J AU Heath, DG Anderson, GW Mauro, JM Welkos, SL Andrews, GP Adamovicz, J Friedlander, AM AF Heath, DG Anderson, GW Mauro, JM Welkos, SL Andrews, GP Adamovicz, J Friedlander, AM TI Protection against experimental bubonic and pneumonic plague by a recombinant capsular F1-V antigen fusion protein vaccine SO VACCINE LA English DT Article DE Yersinia pestis; recombinant vaccine; plague ID YERSINIA-PESTIS; V-ANTIGEN; ACTIVE IMMUNIZATION; MICE; VIRULENCE; PEPTIDE; PSEUDOTUBERCULOSIS; FRACTION-1; IMMUNITY; PLASMID AB The current human whole-cell vaccine is ineffective against pneumonic plague caused by typical F1 capsule positive (F1(+)) strains of Yersinia pestis. The authors found this vaccine to also be ineffective against F1-negative (F1(-)) Y. pestis strains, which have been isolated from a human case and from rodents. For these reasons, the authors developed a recombinant vaccine composed of a fusion protein of F1 with a second protective immunogen, V antigen. This vaccine protected experimental mice against pneumonic as well as bubonic plague produced by either an F1(+) or F1(-) strain of Y. pestis, gave better protection than F1 or V alone against the F1(+) strain, and may provide the basis for an improved human plague vaccine. Published by Elsevier Science Ltd. C1 USA, Med Res Inst Infect Dis, Bacteriol Div, Ft Detrick, MD 21702 USA. Geocenters Inc, Ft Washington, MD 20744 USA. USN, Res Lab, Ft Washington, MD 20744 USA. RP Friedlander, AM (reprint author), USA, Med Res Inst Infect Dis, Bacteriol Div, Ft Detrick, MD 21702 USA. EM friedlan@ncifcrf.gov NR 43 TC 187 Z9 201 U1 0 U2 10 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0264-410X J9 VACCINE JI Vaccine PD JUL PY 1998 VL 16 IS 11-12 BP 1131 EP 1137 DI 10.1016/S0264-410X(98)80110-2 PG 7 WC Immunology; Medicine, Research & Experimental SC Immunology; Research & Experimental Medicine GA ZX643 UT WOS:000074539100011 PM 9682370 ER PT J AU Greason, KL Murray, JD Hemp, JR Hatter, DG Riffenburgh, RH AF Greason, KL Murray, JD Hemp, JR Hatter, DG Riffenburgh, RH TI Ischemic monomelic neuropathy - A case report and literature review SO VASCULAR SURGERY LA English DT Article ID VASCULAR ACCESS; HEMODIALYSIS; ANGIOACCESS; COMPLICATIONS; SURGERY; FISTULA AB Ischemic monomelic neuropathy is an infrequent complication associated with the creation of a hemodialysis arteriovenous fistula. The etiology is unknown but most likely includes an ischemic insult to the proximal limb that results in multiple distal axonal loss mononeuropathies. Risk factors include female sex and diabetes. Clinical presentation commonly includes motor loss, sensory loss, or rest pain developing within 24 hours of the fistula placement. These findings are not specific for ischemic monomelic neuropathy. This often results in a delay of diagnosis. Electromyographic/nerve conduction velocity studies can help substantiate the diagnosis in questionable cases. Methods of treatment vary but should include some attempt at improving distal perfusion of the limb. Ligation of the fistula has been the most commonly employed maneuver. Early treatment results in significant improvement. C1 USN, Med Ctr, Dept Gen Surg, San Diego, CA 92134 USA. RP Greason, KL (reprint author), USN, Med Ctr, Dept Surg, Div Vasc Surg, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 17 TC 2 Z9 2 U1 0 U2 3 PU WESTMINSTER PUBL INC PI GLEN HEAD PA 708 GLEN COVE AVE, GLEN HEAD, NY 11545 USA SN 0042-2835 J9 VASCULAR SURG JI Vasc. Surg. PD JUL-AUG PY 1998 VL 32 IS 4 BP 385 EP 390 DI 10.1177/153857449803200420 PG 6 WC Surgery; Peripheral Vascular Disease SC Surgery; Cardiovascular System & Cardiology GA ZZ975 UT WOS:000074788200020 ER PT J AU Everett, RK Matic, P Harvey, DP Kee, A AF Everett, RK Matic, P Harvey, DP Kee, A TI The microstructure and mechanical response of porous polymers SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT Symposium on Integrated Experimental-Computational Modelling of Advanced Materials (McNu 97) CY JUN 29-JUL 02, 1997 CL NORTHWESTERN UNIV, EVANSTON, ILLINOIS HO NORTHWESTERN UNIV DE porous polymers; microstructures; mechanical response ID COMPRESSION; FOAMS AB Porous polymers exhibit complex microstructures which affect their mechanical and physical properties. Pores in the microstructure are the result of the addition of polymer microspheres, and potentially by gas entrained during mixing operations. A combination of direct observation and finite element modeling has shown that accounting for the stiffening effect of the microspheres is important, and that strain localization occurs due to microstructural heterogeneity and interactions generated by the large gas pores. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Mech Mat Branch, Washington, DC 20375 USA. Geo Ctr Inc, Ft Washington, MD 20749 USA. RP Everett, RK (reprint author), USN, Res Lab, Mech Mat Branch, Code 6382, Washington, DC 20375 USA. OI Everett, Richard/0000-0002-6725-9442 NR 8 TC 4 Z9 6 U1 0 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 JUN 30 PY 1998 VL 249 IS 1-2 BP 7 EP 13 DI 10.1016/S0921-5093(98)00557-7 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 109FG UT WOS:000075310200003 ER PT J AU Kee, A Matic, P Everett, RK AF Kee, A Matic, P Everett, RK TI A mesoscale computer simulation of multiaxial yield in gasar porous copper SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT Symposium on Integrated Experimental-Computational Modelling of Advanced Materials (McNu 97) CY JUN 29-JUL 02, 1997 CL NORTHWESTERN UNIV, EVANSTON, ILLINOIS HO NORTHWESTERN UNIV DE mesoscale computer simulation; multiaxial yield; gasar porous copper AB The mesoscale biaxial plastic flow of a porous copper material produced by the 'gasar' gas-eutectic solidification process is examined in this study. The pore morphology is characterized by elongated, oriented and partially ordered pores. Tensile and compressive testing suggested a very anisotropic yield response, weak coupling between stresses generated by deformations applied in the directions parallel to and transverse to the longitudinal pore axes, and bulk density decreases associated with compression in the longitudinal direction. A two dimensional explicit finite element model, based on an image of the microstructure, was subjected to combinations of tensile, zero and compressive displacement loads applied to the model boundaries. The simulations provided insight into the evolution of local micro yielding, plastic connectivity across the microstructures and buckling of the pores to explain the experimental observations. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Geo Ctr Ltd, Ft Washington, MD 20749 USA. USN, Res Lab, Mech Mat Branch, Washington, DC 20375 USA. RP Kee, A (reprint author), Geo Ctr Ltd, POB 441340, Ft Washington, MD 20749 USA. OI Everett, Richard/0000-0002-6725-9442 NR 7 TC 9 Z9 12 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 JUN 30 PY 1998 VL 249 IS 1-2 BP 30 EP 39 DI 10.1016/S0921-5093(98)00560-7 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 109FG UT WOS:000075310200006 ER PT J AU Lancaster, DG Goldberg, L Koplow, J Curl, RF Tittel, FK AF Lancaster, DG Goldberg, L Koplow, J Curl, RF Tittel, FK TI Fibre coupled difference frequency generation utilising ytterbium-doped fibre amplifier and periodically poled LiNbO3 SO ELECTRONICS LETTERS LA English DT Article ID AGGAS2; POWER AB A new mid-infrared tunable spectroscopic source based on fibre coupled difference frequency generation in bulk periodically-poled LiNbO3 for trace gas detection is reported. The source mixes the outputs of a fibre coupled external cavity diode laser and a 1083nm seeded Yb-doped fibre amplifier. Powers up to 0.8 mu W are obtained in the 3.8-4.3 mu m range. C1 Rice Univ, Rice Quantum Inst, Houston, TX 77005 USA. USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Lancaster, DG (reprint author), Rice Univ, Rice Quantum Inst, 6100 Main St, Houston, TX 77005 USA. RI Lancaster, David/J-4215-2016 OI Lancaster, David/0000-0002-1299-8600 NR 9 TC 12 Z9 12 U1 1 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 JUN 25 PY 1998 VL 34 IS 13 BP 1345 EP 1347 DI 10.1049/el:19980917 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 103AC UT WOS:000074957600051 ER PT J AU Mayers, DL AF Mayers, DL TI Drug-resistant HIV-1 - The virus strikes back SO JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION LA English DT Editorial Material ID TYPE-1; TRANSMISSION C1 USN, Med Res Inst, Viral & Rickettsial Dis Program, Bethesda, MD 20889 USA. RP Mayers, DL (reprint author), USN, Med Res Inst, Viral & Rickettsial Dis Program, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. EM dmayers@pasteur.hjf.org NR 20 TC 31 Z9 32 U1 0 U2 0 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0098-7484 J9 JAMA-J AM MED ASSOC JI JAMA-J. Am. Med. Assoc. PD JUN 24 PY 1998 VL 279 IS 24 BP 2000 EP 2002 DI 10.1001/jama.279.24.2000 PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA ZU945 UT WOS:000074252100040 PM 9643867 ER PT J AU Sedegah, M Jones, TR Kaur, M Hedstrom, R Hobart, P Tine, JA Hoffman, SL AF Sedegah, M Jones, TR Kaur, M Hedstrom, R Hobart, P Tine, JA Hoffman, SL TI Boosting with recombinant vaccinia increases immunogenicity and protective efficacy of malaria DNA vaccine SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE Plasmodium; cytotoxic T lymphocytes; interferon-gamma ID CD8+ T-CELLS; CIRCUMSPOROZOITE PROTEIN; PLASMID DNA; VIRUS; IMMUNITY; IMMUNIZATION; SPOROZOITES; INTERFERON; EXPRESSION; GENES AB To enhance the efficacy of DNA malaria vaccines, we evaluated the effect on protection of immunizing with various combinations of DNA, recombinant vaccinia virus, and a synthetic peptide. Immunization of BALB/c mice with a plasmid expressing Plasmodium yoelii (Py) circumsporozoite protein (CSP) induces H-2K(d)-restricted CD8+ cytoxic T lymphocyte (CTL) responses and CD8+ T cell- and interferon (IFN)-gamma-dependent protection of mice against challenge with Py sporozoites. Immunization with a multiple antigenic peptide, including the only reported H-2K(d)-restricted CD8+ T cell epitope on the PyCSP (PyCSP CTL multiple antigenic peptide) and immunization with recombinant vaccinia expressing the PyCSP induced CTL but only modest to minimal protection, Mice were immunized with PyCSP DNA, PyCSP CTL multiple antigenic peptide, or recombinant vaccinia expressing PyCSP, were boosted 9 wk later with the same immunogen or one of the others, and were challenged, Only mice immunized with DNA and boosted with vaccinia PyCSP (D-V) (11/16: 69%) or DNA (D-D) (7/16: 44%) had greater protection (P < 0.0007) than controls. D-V mice had significantly higher individual levels of antibodies and class I-restricted CTL activity than did D-D mice; IFN-gamma production by ELIspot also was higher in D-V than in D-D mice. In a second experiment. three different groups of D-V mice each had higher levels of protection than did D-D mice, and IFN-gamma production was significantly greater in D-V than in D-D mice. The observation that priming with pyCSP DNA and boosting with vaccinia-PyCSP is more immunogenic and protective than immunizing with PyCSP DNA alone supports consideration of a similar sequential immunization approach in humans. C1 USN, Med Res Inst, Malaria Program, Rockville, MD 20852 USA. Univ Maryland, Sch Med, Dept Microbiol, Baltimore, MD 21201 USA. Vical Inc, San Diego, CA 92121 USA. Virogenet Corp, Troy, NY 12180 USA. RP Hoffman, SL (reprint author), USN, Med Res Inst, Malaria Program, 12300 Washington Ave, Rockville, MD 20852 USA. EM hoffmans@nmripo.nmri.nnmc.navy.mil NR 25 TC 177 Z9 182 U1 1 U2 4 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD JUN 23 PY 1998 VL 95 IS 13 BP 7648 EP 7653 DI 10.1073/pnas.95.13.7648 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZW683 UT WOS:000074436400074 PM 9636204 ER PT J AU Tsai, TE Williams, GM Friebele, EJ AF Tsai, TE Williams, GM Friebele, EJ TI Uniform component of index structure induced in Ge-SiO2 fibers by spatially modulated ultraviolet light SO APPLIED PHYSICS LETTERS LA English DT Article ID BRAGG AB Experimental data are presented to show that Ge(1) and Ge(2) centers are induced by trapping photoinduced electrons from the conduction band, in agreement with our previous proposal that both are trapped electron centers. The spacing (Lambda) dependence of ultraviolet (UV) light bleaching of the pre-existing Ge E' centers illustrates that the electron diffusion length is greater than Lambda of the spatially modulated UV light used in the fabrication of fiber Bragg gratings (FBGs) with Bragg wavelengths less than or equal to 1.5 mu m (short period grating) for laser powers as low as 25 mJ/cm(2). The Ge(1) and Ge(2) centers are uniformly induced by the spatially modulated UV light and therefore contribute to the uniform component of the index structure of FBGs. [S0003-6951(98)01325-4]. C1 USN, Res Lab, Washington, DC 20375 USA. Virginia Polytech Inst & State Univ, Fiber & Electroopt Res Ctr, Blacksburg, VA 24061 USA. RP Tsai, TE (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 11 TC 9 Z9 9 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 JUN 22 PY 1998 VL 72 IS 25 BP 3243 EP 3245 DI 10.1063/1.121678 PG 3 WC Physics, Applied SC Physics GA 108PJ UT WOS:000075274400001 ER PT J AU Duncan, MD Bashkansky, M AF Duncan, MD Bashkansky, M TI Focus issue: Optical methods for material inspection - Introduction SO OPTICS EXPRESS LA English DT Editorial Material C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Duncan, MD (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 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 JUN 22 PY 1998 VL 2 IS 13 BP 515 EP 515 PG 1 WC Optics SC Optics GA 122XF UT WOS:000076096200001 PM 19381223 ER PT J AU Duncan, MD Bashkansky, M AF Duncan, MD Bashkansky, M TI Subsurface defect detection in materials using optical coherence tomography SO OPTICS EXPRESS LA English DT Article ID DOMAIN REFLECTOMETRY AB We have used optical coherence tomography to study the internal structure of a variety of non-biological materials. In particular, we have imaged internal regions from a commercial grade of lead zirconate titanate ceramic material, from a sample of single-crystal silicon carbide, and from a Teflon-coated wire. In each case the spatial positions of internal defects were determined. (C) 1998 Optical Society of America. C1 USN, Res Lab, Washington, DC 20375 USA. RP Duncan, MD (reprint author), USN, Res Lab, Code 5642, Washington, DC 20375 USA. NR 8 TC 43 Z9 43 U1 1 U2 2 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 JUN 22 PY 1998 VL 2 IS 13 BP 540 EP 545 PG 6 WC Optics SC Optics GA 122XF UT WOS:000076096200004 PM 19381226 ER PT J AU Esarey, E Hafizi, B Hubbard, R Ting, A AF Esarey, E Hafizi, B Hubbard, R Ting, A TI Trapping and acceleration in self-modulated laser wakefields SO PHYSICAL REVIEW LETTERS LA English DT Article ID WAKE-FIELD ACCELERATION; ELECTRON ACCELERATION; RAMAN-SCATTERING; PLASMAS; PULSE; PROPAGATION; BREAKING AB Trapping of plasma electrons in the self-modulated laser wakefield accelerator via the coupling of Raman backscatter to the wake is examined analytically and with 3D test particle simulations. The trapping threshold for linear polarization is much less than for circular polarization and occurs for wake amplitudes of 25%, which is well below wave breaking. Self-channeling provides continuous focusing of the accelerated electrons, which, along with relativistic pump laser effects, can enhance the energy gain by a factor of greater than or equal to 2. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Icarus Res Inc, Bethesda, MD 20824 USA. RP Esarey, E (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 30 TC 68 Z9 69 U1 4 U2 10 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 JUN 22 PY 1998 VL 80 IS 25 BP 5552 EP 5555 DI 10.1103/PhysRevLett.80.5552 PG 4 WC Physics, Multidisciplinary SC Physics GA ZV521 UT WOS:000074313000023 ER PT J AU Berry, A Mowery, R Turner, NH Seitzman, L Dunn, D Ladouceur, H AF Berry, A Mowery, R Turner, NH Seitzman, L Dunn, D Ladouceur, H TI Low-temperature deposition of films from tetrakis(dimethylamido)titanium and ammonia SO THIN SOLID FILMS LA English DT Letter DE tetrakis(dimethylamido)titanium (TDMAT); chemical vapor deposition; nanocrystallite ID CHEMICAL-VAPOR-DEPOSITION; NITRIDE THIN-FILMS; TIN; TETRAKIS(DIMETHYLAMIDO)TITANIUM; GROWTH AB We report the chemical vapor deposition (CVD) and characterization of thin films grown from the reaction of tetrakis(dimethylamido)titanium (Ti(NMe2)(4), TDMAT) with NH3 at 423 K. These films, deposited on a variety of substrates, are amorphous except for a small number of embedded nanocrystallites. The films exhibit peeling at thicknesses greater than ca. 200 nm on all substrates and show no visible evidence of etching after exposure to concentrated hydrochloric or nitric acid for 5 min. X-ray photoelectron spectroscopy (XPS) results yield a N/Ti ratio of 0.89 after normalizing the data to that of a TiN standard. The O/Ti ratio varies from 0.26 to 0.66, and the C content is less than 1 at.%. Transmission Fourier transform infrared (FTIR) spectroscopy of films deposited on Si gives spectra consistent with the presence of N-H bonds. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Berry, A (reprint author), USN, Res Lab, Div Chem, Washington, DC 20375 USA. NR 27 TC 6 Z9 6 U1 2 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD JUN 22 PY 1998 VL 323 IS 1-2 BP 10 EP 17 DI 10.1016/S0040-6090(97)00963-2 PG 8 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA ZZ596 UT WOS:000074746000003 ER PT J AU Campbell, ML AF Campbell, ML TI Temperature dependent study of the gas-phase kinetics of Zr(a(3)F(2)) and Hf(a(3)F(2)) SO JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS LA English DT Article ID TRANSITION-METAL ATOMS; EXOTHERMIC HOMOLOGOUS REACTIONS; ACTIVATION BARRIERS; OXIDATION REACTIONS; MOLECULAR WATER; CHROMIUM ATOMS; N2O; O-2; SERIES; NO AB The second-order rate constants of gas-phase Zr(a F-3(2)) and Hf(a F-3(2)) With O-2, N2O, CO2, NO, H2O, SO2 and SF6 as a function of temperature are reported. For Zr(a F-3(2)), th, bimolecular rate constants tin molecule(-1) cm(3) s(-1)) are described in Arrhenius form by k(O-2) = (2.6 +/- 0.5) x 10(-10) exp(- 6.2 +/- 0.7 kJ mol(-1)/RT), k(N2O) = (1.6 +/- 0.3) x 10(-10) exp(-3.3 +/- 0.6 kJ mol(-1)/RT), k(CO2) = (1.4 +/- 0.2) x 10(-10) exp(-5.1 +/- 0.4 kJ mol(-1)/RT), k(NO)=(1.6 +/- 0.3) x 10(-10) exp(-1.9 +/- 0.5 kJ mol(-1)/RT) and k(SF6)= (3.4 +/- 1.3) x 10(-10) exp(-28 +/- 2 kJ mol(-1)/RT), where the uncertainties are +/-2 sigma. The rate constants for Zr reacting with H2O and SO2 were temperature insensitive with room-temperature rate constants of 9.1 x 10(-11) and 3.5 x 10(-10) molecule(-1) cm(3) s(-1), respectively. For Hf(a F-3(2)), the bimolecular rate constants are described in Arrhenius form by k(O-2) = (1.2 +/- 0.1) x 10(-10) exp(-2.8 +/- 0.3 kJ mol(-1)/RT), k(N2O) = (1.5 +/- 0.2) x 10(-10) exp(-11.3 +/- 0.5 kJ mol(-1)/RT), k(CO2)=(1.4 +/- 0.2) x 10(-10) exp(-17.5 +/- 1.2 kJ mol(-1)/RT), k(H2O)= (2.1 +/- 0.3) x 10(-11) exp(-3.4 +/- 0.6 kJ mol(-1)/RT), k(SF6)= (7 +/- 5) x 10(-10) exp(-41 +/- 3 kJ mol(-1)/RT). The rate constants for Hf reacting with NO and SO2 were temperature insensitive with room-temperature rate constants of 1.0 x 10(-10) and 3.0 x 10-10 molecule(-1) cm(3) s(-1), respectively. The disappearance rates for all the reactants are independent of total pressure, indicating bimolecular abstraction processes. C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP Campbell, ML (reprint author), USN Acad, Dept Chem, Annapolis, MD 21402 USA. NR 63 TC 17 Z9 17 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE CB4 4WF, CAMBS, ENGLAND SN 0956-5000 J9 J CHEM SOC FARADAY T JI J. Chem. Soc.-Faraday Trans. PD JUN 21 PY 1998 VL 94 IS 12 BP 1687 EP 1693 DI 10.1039/a801629a PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZW491 UT WOS:000074416300005 ER PT J AU Haltrin, VI AF Haltrin, VI TI Self-consistent approach to the solution of the light transfer problem for irradiances in marine waters with arbitrary turbidity, depth, and surface illumination. I. Case of absorption and elastic scattering SO APPLIED OPTICS LA English DT Article ID RADIATIVE-TRANSFER; EQUATION; OCEAN; MODEL AB A self-consistent variant of the two-flow approximation that takes into account strong anisotropy of light scattering in seawater of finite depth and arbitrary turbidity is presented. To achieve an appropriate accuracy, this approach uses experimental dependencies between downward and total mean cosines. It calculates irradiances, diffuse attenuation coefficients, and diffuse reflectances in waters with arbitrary values of scattering, backscattering, and attenuation coefficients. It also takes into account arbitrary conditions of illumination and reflection from the bottom with the Lambertian albedo. This theory can be used for the calculation of apparent optical properties in both open and coastal oceanic waters, lakes, and rivers. It can also be applied to other types of absorbing and scattering medium such as paints, photographic emulsions, and biological tissues. (C) 1998 Optical Society of America. C1 USN, Res Lab, Ocean Sci Branch, Stennis Space Ctr, MS 39529 USA. RP Haltrin, VI (reprint author), USN, Res Lab, Ocean Sci Branch, Code 7331, Stennis Space Ctr, MS 39529 USA. NR 41 TC 21 Z9 26 U1 0 U2 3 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 JUN 20 PY 1998 VL 37 IS 18 BP 3773 EP 3784 DI 10.1364/AO.37.003773 PG 12 WC Optics SC Optics GA ZT886 UT WOS:000074127900002 PM 18273348 ER PT J AU Koplow, JP Kliner, DAV Goldberg, L AF Koplow, JP Kliner, DAV Goldberg, L TI Development of a narrow-band, tunable, frequency-quadrupled diode laser for UV absorption spectroscopy SO APPLIED OPTICS LA English DT Article ID HIGH-POWER; 2ND-HARMONIC GENERATION; SEMICONDUCTOR-LASER; OPTICAL AMPLIFIER; COEFFICIENTS; SYSTEM; STATE; LIGHT; BLUE; SO2 AB A compact, lightweight, low-power-consumption source of tunable, narrow-bandwidth blue and UV radiation is described. In this source, a single-longitudinal-mode diode laser seeds a pulsed, GaAlAs tapered amplifier whose similar to 860-nm output is frequency quadrupled by two stages of single-pass frequency doubling. Performance of the laser system is characterized over a wide range of amplifier duty cycles (0.1-1.0), pulse durations (50 ns-1.0 mu s), peak currents (less than or equal to 14 A), and average currents (less than or equal to 2.0 A). The capabilities and limitations of this source are discussed. We recorded high-resolution, Doppler-limited absorption spectra of nitric oxide and sulfur dioxide near 215 MI; the SO2 spectrum was found to have significantly more structure and higher peak absorption cross sections than previously reported. (C) 1998 Optical Society of America. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Koplow, JP (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 31 TC 21 Z9 23 U1 1 U2 4 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 JUN 20 PY 1998 VL 37 IS 18 BP 3954 EP 3960 DI 10.1364/AO.37.003954 PG 7 WC Optics SC Optics GA ZT886 UT WOS:000074127900017 PM 18273363 ER PT J AU Tateyama, CE Kingham, KA Kaufmann, P Piner, BG de Lucena, AMP Botti, LCL AF Tateyama, CE Kingham, KA Kaufmann, P Piner, BG de Lucena, AMP Botti, LCL TI Observations of BL Lacertae from the geodetic VLBI archive of the Washington correlator SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL Lacertae objects, individual (BL Lacertae); galaxies, jets; radio continuum, galaxies; techniques, interferometric ID RELATIVISTIC JETS; RADIO-SOURCES; 3C-345; NUCLEI; MODEL; CORE AB We present maps of BL Lac obtained from geodetic VLBI data from the archive of the Washington correlator. The observations were made from 1996 March to 1996 November, with periods from one experiment to another as short as 1 month. The dominant structure of the maps is given by a superluminal component (C2) moving predominantly at position angle similar to 190 degrees. At the later epochs a new superluminal component (C3) emerges from the core and moves along a trajectory at a higher position angle (200 degrees). We also include maps from observations made in 1995 June and August showing the main component (C2) in the early stages of its evolution, as well as an older component (C1). The position angle of the component C1 is nearly the same as that of the new component C3. The component C2 shows indications of nonradial motion, which is discussed in terms of a helically distorted jet. The best fit was obtained for a half-opening angle of the jet of 2.degrees 6 and an angle of the helical axis to the line of sight of 17 degrees. C1 Univ Sao Paulo, Escola Politecn, Ctr Radio Astron & Aplicacoes Espacias, CRAAE, BR-05424970 Sao Paulo, Brazil. USN Observ, Earth Orientat Dept, Washington, DC 20392 USA. UNICAMP, NUCATE, Ctr Radio Astron & Aplicacoes Espacias, BR-13083592 Campinas, SP, Brazil. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. INPE, CRAAE, Radio Observ Espacial Nordeste, Fortaleza, Ceara, Brazil. RP Tateyama, CE (reprint author), Univ Sao Paulo, Escola Politecn, Ctr Radio Astron & Aplicacoes Espacias, CRAAE, CP61548, BR-05424970 Sao Paulo, Brazil. NR 23 TC 22 Z9 22 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 20 PY 1998 VL 500 IS 2 BP 810 EP 815 DI 10.1086/305783 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZX419 UT WOS:000074513900023 ER PT J AU De Pree, CG Goss, WM Gaume, RA AF De Pree, CG Goss, WM Gaume, RA TI Ionized gas in Sagittarius B2 Main on scales of 0.065 arcseconds (600 AU) SO ASTROPHYSICAL JOURNAL LA English DT Article DE H II regions; ISM : individual (Sagittarius B2); radio continuum : ISM ID H-II REGIONS AB The ionized gas in the Sagittarius B2 Main star-forming region has been imaged with similar to 65 mas (600 AU) resolution using the Very Large Array (VLA) at 7 mm in the A configuration. These observations have similar to 4-5 times the resolution of the previous highest resolution images of this source. These VLA observations show that the central four ultracompact H II (UC H II) regions in Sgr B2 Main (F1, F2, F3, and F4) break up into similar to 20 separate UC H II regions. The individual sources have small resolved sizes (similar to 10(-3) pc), high derived emission measures (EM similar to 10(9) pc cm(-6)), and high rms electron densities (n(e) similar to 10(6) cm(-3)). We compare the observed radius and derived emission measure of each of these regions with those expected for a UC H II region in pressure equilibrium with its environment, using previously published temperatures and densities for the Sgr B2 molecular core (n(H2) = 2 x 10(7) cm(-3)). We find that the observed emission measures are in fact higher than those predicted in a simple pressure-confinement model, suggesting that the molecular densities on scales that confine the UC H II regions may be higher than 2 x 10(7) cm(-3). C1 Agnes Scott Coll, Dept Phys & Astron, Decatur, GA 30030 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. USN Observ, Washington, DC 20392 USA. RP De Pree, CG (reprint author), Agnes Scott Coll, Dept Phys & Astron, Decatur, GA 30030 USA. NR 19 TC 45 Z9 45 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 20 PY 1998 VL 500 IS 2 BP 847 EP 852 DI 10.1086/305782 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZX419 UT WOS:000074513900027 ER PT J AU Grove, JE Johnson, WN Kroeger, RA McNaron-Brown, K Skibo, JG Phlips, BF AF Grove, JE Johnson, WN Kroeger, RA McNaron-Brown, K Skibo, JG Phlips, BF TI Gamma-ray spectral states of galactic black hole candidates SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; black hole physics; gamma rays : observations; radiation mechanisms : thermal; X-rays : stars ID ADVECTION-DOMINATED ACCRETION; TRANSIENT GRO J1655-40; SUPERLUMINAL SOURCE; GX 339-4; X-RAYS; NOVA; VARIABILITY; CYGNUS-X-1; GRANAT; RADIO AB OSSE has observed seven transient black hole candidates: GRO J0422+32, GX 339-4, GRS 1716-249, GRS 1009-45, 4U 1543-47, GRO J1655-40, and GRS 1915 + 105. Two gamma-ray spectral states are evident, and based on a limited number of contemporaneous X-ray and gamma-ray observations, these states appear to be correlated with X-ray states. The former three objects show hard spectra below 100 keV (photon number indices Gamma < 2) that are exponentially cut off with folding energy similar to 100 keV, a spectral form that is consistent with thermal Comptonization. This "breaking gamma-ray state" is the high-energy extension of the X-ray low, hard state. In this state, the majority of the luminosity is above the X-ray band, carried by photons of energy similar to 100 keV. The latter four objects exhibit a "power-law gamma-ray state," with a relatively soft spectral index (Gamma similar to 2.5-3) and no evidence for a spectral break. For GRO J1655-40, the lower limit on the break energy is 690 keV. GRS 1716-249 exhibits both spectral states, with the power-law state having significantly lower gamma-ray luminosity. The power-law gamma-ray state is associated with the presence of a strong ultrasoft X-ray excess (kT similar to 1 keV), the signature of the X-ray high, soft (or perhaps very high) state. The physical process responsible for the unbroken power law is not well understood, although the spectra are consistent with bulk-motion Comptonization in the convergent accretion flow. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ Space Res Assoc, Washington, DC 20024 USA. RP USN, Res Lab, EO Hulburt Ctr Space Res, Code 7650, Washington, DC 20375 USA. EM grove@osse.nrl.navy.mil RI Johnson, Neil/G-3309-2014 NR 86 TC 174 Z9 174 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 JUN 20 PY 1998 VL 500 IS 2 BP 899 EP 908 DI 10.1086/305746 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZX419 UT WOS:000074513900033 ER PT J AU Krall, J Chen, J Santoro, R Spicer, DS Zalesak, ST Cargill, PJ AF Krall, J Chen, J Santoro, R Spicer, DS Zalesak, ST Cargill, PJ TI Simulation of buoyant flux ropes in a magnetized solar atmosphere SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; Sun : atmosphere; Sun : magnetic fields ID CLOUDS; TUBES; EVOLUTION; MAGNETOHYDRODYNAMICS; INSTABILITY; PLASMA; FIELDS; SUN AB Dynamics are investigated for buoyant flux ropes in a gravitationally stratified solar atmosphere using realistic chromosphere and corona parameters. Two-dimensional magnetohydrodynamic simulations of horizontally oriented flux ropes are performed under the approximation that the flux rope remains parallel to the solar surface as it rises. As expected, this motion tends to halt at the chromosphere-corona boundary, where the buoyancy force drops significantly. It is shown that fragmentation of the rising flux rope into multiple flux bundles can be reduced if the flux-rope field lines are sufficiently twisted and that this is consistent with previous results. It is also shown that a weak, vertically oriented ambient magnetic field, (B-a/B-tube)(2) much less than 1, can prevent fragmentation of an untwisted flux tube. A vertical field of sufficient strength, but still "weak," can direct the upward buoyancy-driven flow so that the untwisted flux tube penetrates the chromosphere-corona boundary. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. USN, Res Lab, Washington, DC 20375 USA. NASA, Goddard Space Flight Ctr, Ctr Computat Sci, Greenbelt, MD 20771 USA. Univ London Imperial Coll Sci Technol & Med, London SW7 2BZ, England. RP USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 32 TC 17 Z9 17 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD JUN 20 PY 1998 VL 500 IS 2 BP 992 EP 1002 DI 10.1086/305754 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZX419 UT WOS:000074513900041 ER PT J AU Price, GL AF Price, GL TI Shifts on the hyperfinite Pi(1) factor SO JOURNAL OF FUNCTIONAL ANALYSIS LA English DT Article ID POWERS BINARY SHIFTS; CANONICAL SHIFTS; TYPE-II1 FACTORS; ENTROPY; SUBFACTORS; CONJUGACY; FIELDS; INDEX AB Powers has constructed a family of unital endomorphisms of the hyperfinite II1 factor R. The range of each Powers shift sigma is a subfactor of index 2 in R. A cocycle conjugacy invariant for a Powers shift is its commutant index, i.e., the first index k for which the range of sigma(k) has a nontrivial relative commutant in R. Previously we have shown that all Powers shifts of commutant index 2 are cocycle conjugate. In this paper results are obtained on the classification of the cocycle conjugacy classes of Powers shifts of higher commutant index. (C) 1998 Academic Press. C1 USN Acad, Dept Math, Annapolis, MD 21402 USA. RP Price, GL (reprint author), USN Acad, Dept Math, Annapolis, MD 21402 USA. NR 34 TC 9 Z9 9 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-1236 J9 J FUNCT ANAL JI J. Funct. Anal. PD JUN 20 PY 1998 VL 156 IS 1 BP 121 EP 169 DI 10.1006/jfan.1997.3225 PG 49 WC Mathematics SC Mathematics GA 103FM UT WOS:000075147300005 ER PT J AU Kirchoefer, SW Pond, JM Carter, AC Chang, W Agarwal, KK Horwitz, JS Chrisey, DB AF Kirchoefer, SW Pond, JM Carter, AC Chang, W Agarwal, KK Horwitz, JS Chrisey, DB TI Microwave properties of Sr0.5Ba0.5TiO3 thin-film interdigitated capacitors SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE ferroelectric; varactor; interdigitated capacitor ID PULSED-LASER DEPOSITION AB Interdigitated capacitors have been fabricated on ferroelectric thin films of Sr0.5Ba0.5TiO3. These devices have been characterized at microwave frequencies from 50 MHz to 20 GHz, and have a 3.4:1 tuning range over a 1-40 V bias range. This is shown to originate from a relative dielectric constant tuning of 3.8:1. The microwave losses exhibited by these capacitors are comparable to those of commercially available semiconductor varactors for frequencies greater than 1 GHz, and should be useful for tunable microwave circuits in some 300 K applications. (C) 1998 John Wiley & Sons, Inc. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kirchoefer, SW (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 8 TC 75 Z9 79 U1 2 U2 9 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 JUN 20 PY 1998 VL 18 IS 3 BP 168 EP 171 DI 10.1002/(SICI)1098-2760(19980620)18:3<168::AID-MOP3>3.0.CO;2-D PG 4 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA ZN711 UT WOS:000073674000003 ER PT J AU Krowne, CM AF Krowne, CM TI 3-D theory for a radially inhomogeneous microstrip circular ferrite circulator utilizing a recursive dyadic Green's function SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE inhomogeneous ferrite; magnetic walls; microstrip circulator; dyadic Green's function; three dimensional AB Diagonalization of the 3-D governing equations, transverse field construction, field dependence on the perpendicular coordinate, fields within annuli, compact recursion equations in matrix form, and 3-D EH and HH dyadic Green's function elements are treated. Explicit dependence on substrate thickness is given. Magnetic walls are imposed for nonport contour regions. (C) 1998 John Wiley & Sons, Inc. C1 USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Washington, DC 20375 USA. RP Krowne, CM (reprint author), USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Code 6850-3, Washington, DC 20375 USA. NR 5 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 JUN 20 PY 1998 VL 18 IS 3 BP 219 EP 227 DI 10.1002/(SICI)1098-2760(19980620)18:3<219::AID-MOP17>3.0.CO;2-Z PG 9 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA ZN711 UT WOS:000073674000017 ER PT J AU Roland, CM Mott, PH AF Roland, CM Mott, PH TI Comment on "Nonaffine deformation and elasticity of polymer networks" SO MACROMOLECULES LA English DT Article ID DIFFUSED-CONSTRAINT THEORY; RUBBER NETWORKS; STRAIN; BIREFRINGENCE 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 21 TC 7 Z9 7 U1 0 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 JUN 16 PY 1998 VL 31 IS 12 BP 4033 EP 4034 DI 10.1021/ma980112z PG 2 WC Polymer Science SC Polymer Science GA ZV811 UT WOS:000074343700038 ER PT J AU Houser, EJ Keller, TM AF Houser, EJ Keller, TM TI Linear ferrocenylene-siloxyl-diacetylene polymers and their conversion to ceramics with high thermal and oxidative stabilities SO MACROMOLECULES LA English DT Article ID RING-OPENING POLYMERIZATION; SILICON-BRIDGED <1>FERROCENOPHANES; TRANSITION-METAL GROUPS; DEPOLYMERIZATION PRODUCTS; ORGANOSILICON POLYMERS; PYROLYSIS; POLY(FERROCENYLSILANES); COPOLYMERS; POLY<(SILYLENE)DIACETYLENES>; COMPOSITES C1 USN, Res Lab, Mat Chem Branch, Div Chem, Washington, DC 20375 USA. RP Keller, TM (reprint author), USN, Res Lab, Mat Chem Branch, Div Chem, CODE 6127, Washington, DC 20375 USA. RI Paquette, Joseph/O-4271-2015 OI Paquette, Joseph/0000-0001-6023-5125 NR 31 TC 32 Z9 32 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JUN 16 PY 1998 VL 31 IS 12 BP 4038 EP 4040 DI 10.1021/ma970181y PG 3 WC Polymer Science SC Polymer Science GA ZV811 UT WOS:000074343700040 ER PT J AU Beal, LCDRFC AF Beal, LCDRFC TI Herbals and homeopathic remedies as formulary items? SO AMERICAN JOURNAL OF HEALTH-SYSTEM PHARMACY LA English DT Editorial Material C1 Def Personnel Support Ctr, Pharmaceut Grp, Philadelphia, PA 19145 USA. USN, Med Clin, Portsmouth, NH 03804 USA. RP Beal, LCDRFC (reprint author), Def Personnel Support Ctr, Pharmaceut Grp, Philadelphia, PA 19145 USA. NR 1 TC 4 Z9 4 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 JUN 15 PY 1998 VL 55 IS 12 BP 1266 EP 1267 PG 2 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA ZV312 UT WOS:000074292000008 ER PT J AU Turner, NH Schreifels, JA AF Turner, NH Schreifels, JA TI Surface analysis: X ray photoelectron spectroscopy and Auger electron spectroscopy SO ANALYTICAL CHEMISTRY LA English DT Review ID CORE-LEVEL SHIFTS; SELF-ASSEMBLED MONOLAYERS; ION MASS-SPECTROMETRY; CYLINDRICAL MIRROR ANALYZER; PEAK SHAPE-ANALYSIS; ANGLE-RESOLVED XPS; QUANTUM-MECHANICAL CALCULATIONS; DENSITY-FUNCTIONAL CALCULATIONS; INELASTIC BACKGROUND ANALYSIS; PRINCIPAL COMPONENT ANALYSIS C1 USN, Div Chem, Res Lab, Washington, DC 20375 USA. George Mason Univ, Dept Chem, Fairfax, VA 22030 USA. RP USN, Div Chem, Res Lab, Washington, DC 20375 USA. NR 468 TC 7 Z9 7 U1 4 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 EI 1520-6882 J9 ANAL CHEM JI Anal. Chem. PD JUN 15 PY 1998 VL 70 IS 12 BP 229R EP 250R PG 22 WC Chemistry, Analytical SC Chemistry GA ZU095 UT WOS:000074161100010 ER PT J AU Chesi, M Bergsagel, PL Shonukan, OO Martelli, ML Brents, LA Chen, T Schrock, E Ried, T Kuehl, VM AF Chesi, M Bergsagel, PL Shonukan, OO Martelli, ML Brents, LA Chen, T Schrock, E Ried, T Kuehl, VM TI Frequent dysregulation of the c-maf proto-oncogene at 16q23 by translocation to an Ig locus in multiple myeloma SO BLOOD LA English DT Article ID CELL-LINE; CHROMOSOMAL TRANSLOCATIONS; GENE; PROTOONCOGENE; LEUKEMIA; LYMPHOMA; MODEL AB Dysregulation of oncogenes by translocation to an IgH (14q32) or IgL (kappa, 2p11 or lambda, 22q11) locus is a frequent event in the pathogenesis of B-cell tumors. Translocations involving an IgH locus and a diverse but nonrandom array of chromosomal loci occur in most multiple myeloma (MM) tumors even though the translocations often are not detected by conventional cytogenetic analysis. In a continuing analysis of translocations in 21 MM lines, we show that the novel, karyotypically silent t(14;16)(q32.3;q23) translocation is present in 5 MM lines, with cloned breakpoints from 4 lines dispersed over an approximately 500-kb region centromeric to the c-maf proto oncogene at 16q23. Another line has a t(16;22)(q23;q11), with the breakpoint telomeric to c-maf, so that the translocation breakpoints in these 6 lines bracket c-maf. Only these 6 lines overexpress c-maf mRNA. As predicted for dysregulation of c-maf by translocation, there is selective expression of one c-maf allele in 2 informative lines with translocations. This is the first human tumor in which the basic zipper c-maf transcription factor is shown to function as an oncogene. C1 USN Hosp, NCI, Med Branch, Dept Genet, Bethesda, MD 20889 USA. Cornell Univ, Coll Med, Dept Med, Div Hematol & Oncol, New York, NY USA. NIH, Natl Ctr Human Genome Res, Genome Technol Branch, Bethesda, MD 20892 USA. RP Kuehl, VM (reprint author), USN Hosp, NCI, Med Branch, Dept Genet, Bldg 8,Room 5101, Bethesda, MD 20889 USA. RI Bergsagel, Peter/A-7842-2011 OI Bergsagel, Peter/0000-0003-1523-7388 NR 28 TC 290 Z9 294 U1 0 U2 3 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 JUN 15 PY 1998 VL 91 IS 12 BP 4457 EP 4463 PG 7 WC Hematology SC Hematology GA ZT469 UT WOS:000074091000007 PM 9616139 ER PT J AU Siskind, DE Summers, ME AF Siskind, DE Summers, ME TI Implications of enhanced mesospheric water vapor observed by HALOE SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SMALL COMETS; ATMOSPHERE; H2O AB Recently reprocessed water vapor data from the Halogen Occultation Experiment (HALOE) on the UARS satellite show significant deviations from the expected constant value of 2*CH4 + H2O. An unusual enhancement in the H2O is seen from 65-70 km which exceeds the stratospheric the value of 2*CH4 + H2O by 0.6-0.8 ppmv. This is inconsistent with the conventional view of transport of H2O and CH4 up from the lower stratosphere and photodissociation in the mesosphere and suggests the presence of another source of H2O. We re-evaluate the hypothesis that there is an extraterrestrial source of water deposited at mesospheric altitudes. The HALOE data above 60 km provide stringent new constraints on the magnitude and altitude of such a source, but cannot rule out the possibility of a small contribution in the middle mesosphere. 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. NR 16 TC 21 Z9 21 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 JUN 15 PY 1998 VL 25 IS 12 BP 2133 EP 2136 DI 10.1029/98GL51608 PG 4 WC Geosciences, Multidisciplinary SC Geology GA ZV204 UT WOS:000074280800032 ER PT J AU Mattoussi, H Radzilowski, LH Dabbousi, BO Thomas, EL Bawendi, MG Rubner, MF AF Mattoussi, H Radzilowski, LH Dabbousi, BO Thomas, EL Bawendi, MG Rubner, MF TI Electroluminescence from heterostructures of poly(phenylene vinylene) and inorganic CdSe nanocrystals SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID LIGHT-EMITTING-DIODES; SMALL SEMICONDUCTOR CRYSTALLITES; POLY(P-PHENYLENE VINYLENE); CONJUGATED POLYMERS; MULTILAYER FILMS; CHARGED SURFACES; IONIC-STRENGTH; ELECTRON; POLYELECTROLYTES; ENHANCEMENT AB Electroluminescence (EL) and photoluminescence (PL) from heterostructure thin films made of organic poly (phenylene vinylene), PPV, and inorganic semiconductor CdSe nanocrystals are investigated. In these devices, the organic PPV structure is built next to an indium tin oxide anode, using the technique of molecular layer-by-layer sequential adsorption, and serves primarily as the hole transport layer. The inorganic layer, adjacent to an Al electrode, is made of spin cast CdSe nanocrystals, passivated with either organic groups or with a wider band gap semiconductor, e.g., ZnS in the present case. We find that the electroluminescence signal is almost exclusively generated within the inorganic layer, with a very weak contribution from the PPV layer at higher applied voltage. The performance of these heterostructure devices is influenced by the thickness of the dot layer. Lifetime tests reveal promising stability, with devices operating continuously over 50-100 h. Values of the external quantum efficiency, eta(ext), as high as 0.1% are reached. The quantum efficiency is not enhanced by the presence of ZnS overcoating, as opposed to the observed increase in the PL quantum yield. This reflects a difference in the efficiency of charge injection into the nanocrystals due to the ZnS overlayer. (C) 1998 American Institute of Physics. C1 MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA. MIT, Dept Chem, Cambridge, MA 02139 USA. RP USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. EM hedimat@ccs.nrl.navy.mil NR 52 TC 456 Z9 468 U1 10 U2 89 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 15 PY 1998 VL 83 IS 12 BP 7965 EP 7974 DI 10.1063/1.367978 PG 10 WC Physics, Applied SC Physics GA 108GJ UT WOS:000075257500078 ER PT J AU Jensen, KL AF Jensen, KL TI Analytical model of an emission-gated Twystrode using a field emitter array SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INDUCTIVE OUTPUT AMPLIFIERS; VACUUM MICROELECTRONICS; OPTIMIZATION AB An analytical model of a unit cell and of an array of field emitters with a distribution of tip radii is used to estimate the total current and current characteristics on the basis of geometry and materials. Based on the unit cell modeling, analytical estimates of ring cathode inductance, resistance, and capacitance are made to estimate the drive power required to sinusoidally modulate the array in order to produce a bunched electron beam. For a configuration of parameters indicative of a next generation field emitter array (FEA) ring cathode, the characteristics of the array are used to estimate the gain, efficiency, power output, and optimized length of an emission-gated Twystrode (TWT) using a simple model of the beam-wave interaction. The integrated analytical approach and its numerical implementation ("Cassandra") are validated by comparison to a 1D TWT code (CHRISTINE) which estimates the output power and the optimized length of a TWT. Using "Cassandra," it is shown that with next generation FEA parameters, interesting and significant levels of performance may be anticipated for a compact, broadband rf inductive output amplifier; in particular, an electronic efficiency of 32% with 15 dB gain may be possible from an array producing 260 mA peak and 71 mA average current at 10 GHz modulation using a helix 1.51 cm long. C1 USN, Res Lab, ESTD, Washington, DC 20375 USA. RP Jensen, KL (reprint author), USN, Res Lab, ESTD, Code 6840, Washington, DC 20375 USA. RI Jensen, Kevin/I-1269-2015 OI Jensen, Kevin/0000-0001-8644-1680 NR 35 TC 13 Z9 13 U1 0 U2 3 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 JUN 15 PY 1998 VL 83 IS 12 BP 7982 EP 7992 DI 10.1063/1.367980 PG 11 WC Physics, Applied SC Physics GA 108GJ UT WOS:000075257500080 ER PT J AU Kelly, KA Beardsley, RC Limeburner, R Brink, KH Paduan, JD Chereskin, TK AF Kelly, KA Beardsley, RC Limeburner, R Brink, KH Paduan, JD Chereskin, TK TI Variability of the near-surface eddy kinetic energy in the California Current based on altimetric, drifter, and moored current data SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article; Proceedings Paper CT World Ocean Circulation Experiment Pacific Workshop CY AUG, 1996 CL NEWPORT BEACH, CALIFORNIA ID OCEAN DYNAMICS EXPERIMENT; COASTAL TRANSITION ZONE; NORTHERN CALIFORNIA; CURRENT SYSTEM; PACIFIC; HEIGHT; FIELD AB Low-pass-filtered velocities obtained from World Ocean Circulation Experiment (WOCE) surface drifters deployed in the California Current off northern California during 1993-1995 have been compared with surface geostrophic velocity estimates made along subtracks of the TOPEX/POSEIDON altimeter and with moored acoustic Doppler current profiler (ADCP) data. To obtain absolute geostrophic velocities, a mean sea surface height (SH) field was estimated using the mean drifter velocities and historical hydrographic data and was added to the altimetric SSH anomalies, The correlation between collocated drifter and,altimetric velocities is 0.73, significant at the 95% level. The component of the drifter velocity which was uncorrelated with the altimetric velocity was correlated with the wind in the Ekman transport sense. Monthly averages of eddy kinetic energy (EKE), estimated using all drifter and altimeter data within the domain (124 degrees-132 degrees W, 33 degrees-40.5 degrees N), show energy levels for the drifters that are about 13% greater than those for the altimeter. Drifter, altimeter, and ADCP measurements all exhibit similar seasonal cycles in EKE, with the altimeter data reaching maximum values of about 0.03 m(2) s(-2) in late summer/fall. Wavenumber spectra of the altimeter velocity indicate that the velocity fluctuations were dominated by features with wavelengths of 240-370 km, while the ADCP data suggest that the temporal scales of these fluctuations are at least several months. Between 36 degrees and 40.5 degrees N, the region of monthly maximum EKE migrates westward to about 128 degrees W on a seasonal timescale. This region of maximum EKE coincides with the maximum zonal SSH gradient, with increased EKE associated with. increased southward flow. A simple model shows that much of the seasonal cycle of the SSH anomalies can be produced by linear prodesses forced by the curl of the wind stress, although the model cannot explain the offshore movement of the front. C1 Woods Hole Oceanog Inst, Dept Phys Oceanog, Woods Hole, MA 02543 USA. Scripps Inst Oceanog, Phys Oceanog Res Div, La Jolla, CA 92093 USA. USN, Postgrad Sch, Monterey, CA 93943 USA. RP Kelly, KA (reprint author), Univ Washington, Appl Phys Lab, Box 355640, Seattle, WA 98195 USA. NR 29 TC 69 Z9 69 U1 0 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 JUN 15 PY 1998 VL 103 IS C6 BP 13067 EP 13083 DI 10.1029/97JC03760 PG 17 WC Oceanography SC Oceanography GA ZU093 UT WOS:000074160900034 ER PT J AU Challa, M Pfeffer, RL Zhao, Q Chang, SW AF Challa, M Pfeffer, RL Zhao, Q Chang, SW TI Can eddy fluxes serve as a catalyst for hurricane and typhoon formation? SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID TROPICAL CYCLONE FORMATION; VERTICAL-MODE INITIALIZATION; ANGULAR-MOMENTUM FLUXES; OBSERVATIONAL ANALYSIS; EXTERNAL INFLUENCES; RAINFALL RATES; PREDICTION; INTENSITY; LAYER; PARAMETERIZATION AB Numerical simulations and diagnostics are performed for Typhoon Tip and Tropical-Storm Faye, both of which occurred during 1979, the year of the First Global GARP (Global Atmosphere Research Program) Experiment (FGGE). The simulations are started from early in the life cycles of both disturbances, the former of which developed into a super typhoon, and the latter of which did not develop beyond the tropical storm stage. The numerical model employed was that of Madala et al. and is a modification of the one used in previous simulations by the authors. The primary modifications are the inclusion of a more sophisticated boundary layer parameterization, based on similarity theory, and the inclusion in the Kuo cumulus parameterization scheme of the nonmeasurable mesoscale latent heat release, as described by Krishnamurti et al. The initial conditions for both simulations were derived from the FGGE dataset of the European Centre for Medium-Range Weather Forecasts and from monthly mean sea surface temperatures provided by the National Meteorological Center (now the National Centers for Environmental Prediction). The initial intensities and the underlying sea surface temperatures were approximately the same for the two disturbances. In the simulations, Tip developed into an intense typhoon and Faye did not develop, as observed in the atmosphere, although the minimum surface pressures and maximum wind speeds attained do not agree quantitatively with the reported values. The primary question the authors set out to answer is what special conditions exist at the early stages of the life cycles of tropical disturbances that allow one system to develop and another to fail to develop into a typhoon. The most significant difference found in the initial states of Tip and Faye was a large-scale eddy flux of angular momentum from the surroundings into the former and out of the latter, with maximum amplitudes located around 200 mb at radial distances from the vortex centers greater than 1000 km. These fluxes persisted for at least 24 h prior to the time the numerical simulations were started. While there were differences in the eddy heat fluxes as well, these were less significant. Diagnostic calculations reveal that the secondary radial circulation induced by the eddy fluxes of momentum and heat transported water vapor inward for Tip and outward for Faye, with the result that convection broke out at an early stage in the vortex center of Tip, but not in Faye. The convection intensified with time in Tip and subsequently became the dominant factor contributing to the moisture inflow and rapid vortex intensification. The authors' interpretation of the results of their numerical simulations and diagnostic calculations is that the secondary radial circulation induced by large-scale eddy fluxes of heat and momentum can serve either as a catalyst for typhoon formation or as a mechanism for inhibiting the further development of an incipient tropical disturbance, depending on the direction of the water vapor transport (into or out of the Vortex core). C1 Florida State Univ, Geophys Fluid Dynam Inst, Tallahassee, FL 32306 USA. Florida State Univ, Dept Meteorol, Tallahassee, FL 32306 USA. USN, Res Lab, Monterey, CA USA. RP Pfeffer, RL (reprint author), Florida State Univ, Geophys Fluid Dynam Inst, Tallahassee, FL 32306 USA. EM pfeffer@gfdi.fsu.edu NR 47 TC 20 Z9 24 U1 0 U2 4 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 JUN 15 PY 1998 VL 55 IS 12 BP 2201 EP 2219 DI 10.1175/1520-0469(1998)055<2201:CEFSAA>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZU121 UT WOS:000074164400005 ER PT J AU Roman, JE Frankel, MY Esman, RD AF Roman, JE Frankel, MY Esman, RD TI Spectral characterization of fiber gratings with high resolution SO OPTICS LETTERS LA English DT Article ID DISPERSION COMPENSATION; OPTICAL-FIBER; FILTERS; DELAY AB We demonstrate a high-resolution technique to measure the optical magnitude and phase responses of fiber gratings. The technique employs single-sideband modulation of an optical source and has spectral resolution in the hertz regime. The technique is demonstrated by measurement of the phase ripples of unapodized and apodized chirped gratings as well as the transmission spectrum of a pi-phase-shifted grating. Although it is demonstrated on fiber gratings, the technique is applicable to any optical device. (C) 1998 Optical Society of America. C1 USN, Res Lab, Washington, DC 20375 USA. RP Roman, JE (reprint author), USN, Res Lab, Code 5672, Washington, DC 20375 USA. NR 12 TC 51 Z9 51 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 JUN 15 PY 1998 VL 23 IS 12 BP 939 EP 941 DI 10.1364/OL.23.000939 PG 3 WC Optics SC Optics GA ZV034 UT WOS:000074261700017 PM 18087390 ER PT J AU Li, YB Blaisten-Barojas, E Papaconstantopoulos, DA AF Li, YB Blaisten-Barojas, E Papaconstantopoulos, DA TI Structure and dynamics of alkali-metal clusters and fission of highly charged clusters SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC SHELL STRUCTURE; SMALL SODIUM CLUSTERS; TOTAL-ENERGY; MOLECULAR-DYNAMICS; ASYMMETRIC FISSION; LITHIUM CLUSTERS; JELLIUM MODEL; BARRIERS; FRAGMENTATION; DISSOCIATION AB A dynamical optimization of the minimum energy cluster structures of Na, K, Rb, and Cs clusters was performed using a many-body potential based on local density calculations. The energetics and vibrational analysis of the neutral clusters in the size range 83.0.CO;2-F PG 14 WC Psychology, Experimental SC Psychology GA ZZ361 UT WOS:000074721700009 ER PT J AU Kang, DR Leong, H Foss, R Martin, P Brooker, CR Seid, AB AF Kang, DR Leong, H Foss, R Martin, P Brooker, CR Seid, AB TI Sutureless cartilage graft laryngotracheal reconstruction using fibrin sealant SO ARCHIVES OF OTOLARYNGOLOGY-HEAD & NECK SURGERY LA English DT Article; Proceedings Paper CT 12th Annual Meeting of the American-Society-of-Pediatric-Otolaryngology CY MAY 14-16, 1997 CL SCOTTSDALE, ARIZONA SP Amer Soc Pediat Otolaryngol ID GLUE AB Objective: To determine whether fibrin sealant can replace suture as a means of holding a cartilage graft securely in the trachea. Design: Randomized blinded control study comparing the use of Abrin sealant vs sutures in laryngotracheal reconstruction in ferrets. We compared results at 7 and 30 days. Subjects: Forty ferrets randomized into 2 groups of 20. fibrin sealant and sutures, Within each group, half were studied at 7 days and the rest at 30 days. No ferrets were withdrawn from study because of adverse effects of the intervention. Intervention: A carved costal cartilage graft was placed in the anterior cricoid split incision, and was secured with either fibrin sealant or sutures. All animals were extubated after recovery from anesthesia. Specimens were examined grossly and histologically. Results: all animals survived until humanely killed. The pathologist, unaware of the groupings, measured lumen expansion in millimeters, cartilage graft migration, mucosal in-growth, degree of inflammation, graft integration, and graft viability. The fibrin sealant group had statistically significant (P < .05) better results in mucosal in-growth. In no categories was the suture group better than the fibrin sealant group. In comparing 7-day with 30-day results, the 30-day group had significantly better results in inflammation and graft viability. Conclusions: Fibrin sealant can be used in place of sutures with improvement in mucosal growth in costal cartilage laryngotracheal reconstruction in the experimental animal model. Use of fibrin sealant (instead of sutures) may result in less surgical trauma and edema, less surgical time, and faster recovery. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Otolaryngol, San Diego, CA 92134 USA. USN, Med Ctr, Dept Lab, Div Pathol, San Diego, CA 92134 USA. Childrens Associated Med Grp, Dept Pediat Otolaryngol, San Diego, CA USA. RP Kang, DR (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 14 TC 5 Z9 5 U1 0 U2 0 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0886-4470 J9 ARCH OTOLARYNGOL JI Arch. Otolaryngol. Head Neck Surg. PD JUN PY 1998 VL 124 IS 6 BP 665 EP 670 PG 6 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA ZU733 UT WOS:000074229000009 PM 9639477 ER PT J AU Luhman, KL Engelbracht, CW Luhman, ML AF Luhman, KL Engelbracht, CW Luhman, ML TI Near-infrared spectroscopy of photodissociation regions: The Orion bar and Orion S SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared, ISM, lines and bands; ISM, individual (Orion Nebula); ISM, molecules; ISM, structure ID PHYSICAL CONDITIONS; LINE-INTENSITIES; NEBULA; EMISSION; MICRON; GAS; SPECTROPHOTOMETRY; CHEMISTRY; PLASMAS; TABLES AB We have obtained moderate-resolution (R similar to 3000) spectra of the Orion bar and Orion S regions at J (1.25 mu m), H (1.64 mu m), and K (2.2 mu m). Toward the bar, the observations reveal a large number of H-2 emission lines that, when compared to model predictions of Draine & Bertoldi, are indicative of a high-density photodissociation region (PDR) (n(H) = 10(6) cm(-3), chi = 10(5), T-0 = 1000 K) rather than of shocked material. Behind the bar and into the molecular cloud, the H-2 spectrum again matches well with that predicted for a dense PDR (n(H) = 10(6) cm(-3)) but with a lower temperature (T-0 = 500 K) and UV field strength (chi = 10(4)). The H-2 spectrum and stratification of near-IR emission lines (O I, H I, [Fe II], [Fe III], H-2) near Orion S imply the presence of a dense PDR with an inclined geometry in this region (n(H) = 10(6) cm(-3), chi = 10(5), T-0 = 1500 K). The extinction measurements toward the bar (A(K) similar to 2.6) and Orion S (A(K) similar to 2.1) H-2 emission regions are much larger than expected from either face-on (A(K) similar to 0.1) or edge-on (A(K) similar to 1) homogeneous PDRs, indicating that clumps may significantly affect the structure of the PDRs. In addition, we have observed the strongest similar to 30 near-IR He I emission lines, many of which have not been detected previously. There is good agreement between most observed and theoretical He I line ratios, while a few transitions with upper levels of n P-3 (particularly 4(3)P-3(3)S 1.2531 mu m) are enhanced over strengths expected from collisional excitation. This effect is possibly due to opacity in the UV series n P-3-2(3)S. We also detect several near-IR [Fe II] and [Fe III] transitions with line ratios indicative of low densities (n(e) similar to 10(3)-10(4) cm(-3)), whereas recent observations of optical [Fe II] emission imply the presence of high-density gas (n(e) similar to 10(6) cm(-3)). These results are consistent with a model in which high-density, partially-ionized gas is the source of the iron transitions observed in the optical, while low-density, fully-ionized material is responsible for the near-IR emission lines. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. USN, Res Lab, NRC, Washington, DC USA. RP Luhman, KL (reprint author), Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. EM kluhman@as.arizona.edu; chad@as.arizona.edu; luhman@irfp1.nrl.navy.mil NR 53 TC 34 Z9 34 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 1 PY 1998 VL 499 IS 2 BP 799 EP 809 DI 10.1086/305682 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZU199 UT WOS:000074172200026 ER EF