FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Bottcher, M Dermer, CD AF Bottcher, M Dermer, CD TI High-energy gamma rays from ultra-high-energy cosmic-ray protons in gamma-ray bursts SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic rays; gamma rays, bursts; radiation mechanisms, nonthermal ID RELATIVISTIC FIREBALLS; ACCELERATION; MODELS AB It has recently been proposed that ultra-high-energy (greater than or equal to 10(19) eV) cosmic rays (UHECRs) are accelerated by the blast waves associated with GRBs. We calculate the observed synchrotron spectrum from protons and energetic leptons formed in the cascades initiated by photopion production, taking into account gamma gamma attenuation at the source. Normalizing to the emission characteristics of GRB 970508,we predict similar to 10 MeV-100 GeV fluxes at a level that may have been observed with EGRET from bright GRBs and could be detected with the proposed GLAST experiment or with ground-based air Cerenkov telescopes having thresholds less than or equal to several hundred GeV. The temporal decay of the UHECR-induced high-energy gamma-ray afterglows is significantly slower than that of the lower energy burst and associated synchrotron self-Compton (SSC) radiation, which provides a direct way to test the hadronic origin of a high-energy GRB afterglow. Besides testing the UHECR origin hypothesis, the short-wavelength emission and afterglows can be used to probe the level of the diffuse intergalactic infrared radiation field or constrain redshifts of GRB sources. C1 Rice Univ, Dept Space Phys & Astron, Houston, TX 77005 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Rice Univ, Dept Space Phys & Astron, 6100 Main St, Houston, TX 77005 USA. NR 30 TC 109 Z9 110 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 1 PY 1998 VL 499 IS 2 BP L131 EP L134 DI 10.1086/311366 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZU234 UT WOS:000074175800005 ER PT J AU Sanford, MS Charles, PT Commisso, SM Roberts, JC Conrad, DW AF Sanford, MS Charles, PT Commisso, SM Roberts, JC Conrad, DW TI Photoactivatable cross-linked polyacrylamide for the site-selective immobilization of antigens and antibodies SO CHEMISTRY OF MATERIALS LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; CHEMICAL AMPLIFICATION; IMAGING MATERIALS; POLYMER SURFACES; PROTEIN FIXATION; LIGHT; FABRICATION; MOLECULES; BIOTIN; PHOTOCHEMISTRY AB This paper describes the synthesis, characterization, and photochemical behavior of a new light-activated material for the photoimmobilization of antigens. The material is a derivative of cross-linked polyacrylamide that incorporates photoactive o-nitrobenzyl carbamates. When irradiated, the polymer undergoes a photochemical rearrangement to produce primary amines that can be used as molecular attachment sites. We monitored the photoconversion of thin (1-2 mu m) polymer films that were deposited on silicon wafers or fused silica substrates using FT IR spectroscopy and UV-vis spectroscopy. To produce patterned polymer-modified substrates, we irradiated the material using a photolithographic mask;. This process yielded 10-mu m lines of photogenerated amines, to which an amine-reactive antigen (2,4,6-trintrobenzenesulfonic acid) was covalently bound. When we used this antigen-patterned substrate in a competitive fluorescence immunoassay containing tetramethylrhodamine-labeled anti 2,4-dinitrophenyl antibodies and 2,4-dinitrophenol, concentrations of 2,4-dinitrophenol as low as 2.3 mu g/mL were detectable. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Conrad, DW (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Code 6900, Washington, DC 20375 USA. NR 58 TC 22 Z9 22 U1 0 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD JUN PY 1998 VL 10 IS 6 BP 1510 EP 1520 DI 10.1021/cm970632t PG 11 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZV160 UT WOS:000074275800006 ER PT J AU Campbell, J AF Campbell, J TI "The great something else": Women's search for meaningful work in Sarah Orne Jewett's A 'Country doctor' and Frances E.W. Harper's 'Trial and triumph' SO COLBY QUARTERLY LA English DT Article C1 USN, Broadened Opportun Officer Select & Training Prog, Newport, RI USA. RP Campbell, J (reprint author), USN, Broadened Opportun Officer Select & Training Prog, Newport, RI USA. NR 30 TC 3 Z9 3 U1 0 U2 0 PU COLBY COLLEGE PI WATERVILLE PA COLBY COLLEGE QUARTERLY, WATERVILLE, MA 04901 USA SN 1050-5873 J9 COLBY QUART JI Colby Q. PD JUN PY 1998 VL 34 IS 2 BP 83 EP 98 PG 16 WC Literature SC Literature GA ZZ303 UT WOS:000074715900002 ER PT J AU Brutzman, D AF Brutzman, D TI The virtual reality modeling language and Java SO COMMUNICATIONS OF THE ACM LA English DT Article C1 USN, Postgrad Sch, Monterey, CA 93940 USA. RP Brutzman, D (reprint author), USN, Postgrad Sch, Monterey, CA 93940 USA. NR 12 TC 38 Z9 41 U1 0 U2 4 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 USA SN 0001-0782 J9 COMMUN ACM JI Commun. ACM PD JUN PY 1998 VL 41 IS 6 BP 57 EP 64 DI 10.1145/276609.276620 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA ZQ745 UT WOS:000073898800021 ER PT J AU Sanz, W Platzer, MF AF Sanz, W Platzer, MF TI Numerical investigation of the stall onset behaviour of the GA(W)-1 airfoil SO COMPUTERS & FLUIDS LA English DT Article; Proceedings Paper CT 6th International Symposium on Computational Fluid Dynamics CY SEP, 1995 CL LAKE TAHOE, NEVADA SP Japan Soc Comp Fluid Dynam ID DIFFERENCE AB In this paper the stall onset behaviour of the GA(W)-1 airfoil is numerically investigated. The compressible form of the Reynolds-averaged Navier-Stokes equations is solved with an upwind-biased numerical scheme. An algebraic and a one-equation turbulence model are compared in their ability of predicting stall onset and highly separated flow. The results show significant differences at higher angles of attack and the ability of the one-equation model to predict the maximum lift coefficient. The magnitude and the frequency of the normal force fluctuations are also calculated and compared with the buffeting prediction as described by Mabey (1992). (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Graz Univ Technol, Inst Thermal Turbomachinery & Machine Dynam, A-8010 Graz, Austria. USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Sanz, W (reprint author), Graz Univ Technol, Inst Thermal Turbomachinery & Machine Dynam, A-8010 Graz, Austria. NR 7 TC 1 Z9 1 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-7930 J9 COMPUT FLUIDS JI Comput. Fluids PD JUN-JUL PY 1998 VL 27 IS 5-6 BP 681 EP 687 DI 10.1016/S0045-7930(97)00052-2 PG 7 WC Computer Science, Interdisciplinary Applications; Mechanics SC Computer Science; Mechanics GA ZT124 UT WOS:000074050800013 ER PT J AU Cannon-Bowers, JA Salas, E AF Cannon-Bowers, JA Salas, E TI Team performance and training in complex environments: Recent findings from applied research SO CURRENT DIRECTIONS IN PSYCHOLOGICAL SCIENCE LA English DT Article C1 USN, Air Warfare Ctr Training Syst Div, Orlando, FL 32826 USA. RP Cannon-Bowers, JA (reprint author), USN, Air Warfare Ctr Training Syst Div, Code 4961,12350 Res Pkwy, Orlando, FL 32826 USA. OI Cannon-Bowers, Janis/0000-0003-2154-4456 NR 21 TC 34 Z9 35 U1 0 U2 7 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0963-7214 J9 CURR DIR PSYCHOL SCI JI Curr. Dir. Psychol. PD JUN PY 1998 VL 7 IS 3 BP 83 EP 87 DI 10.1111/1467-8721.ep10773005 PG 5 WC Psychology, Multidisciplinary SC Psychology GA 168YM UT WOS:000078720800004 ER PT J AU Banker, AS Bergeron-Lynn, G Keefe, KS De Clercq, E Taskintuna, I Freeman, WR AF Banker, AS Bergeron-Lynn, G Keefe, KS De Clercq, E Taskintuna, I Freeman, WR TI Effects of topical and subconjunctival cidofovir (HPMPC) in an animal model SO CURRENT EYE RESEARCH LA English DT Article DE cidofovir (HPMPC); cytomegalovirus (CMV) retinitis; guinea pig; topical administration; subconjunctival administration; intravitreal administration; intraocular pressure; hypotony ID CYTOMEGALOVIRUS RETINITIS; INTRAVITREAL CIDOFOVIR; MAINTENANCE TREATMENT; SUSTAINED-RELEASE; ORAL GANCICLOVIR; THERAPY; AIDS; REPLICATION; KERATITIS; DISEASE AB Purpose. To characterize the anterior segment effects of cidofovir, using an animal model. Methods. Cidofovir drops, at concentrations of 0.04%, 0.4% and 4%, were instilled in eyes of guinea pigs once daily for 10 days. Fellow eyes (controls) received normal saline. The corneal epithelium was debrided at day one and then at every other day for 10 days. Subconjunctival injections of 20 mu l of 4% cidofovir were given in another group of animals. A micromanometer was used to determine the intraocular pressure (IOP). Eyes were studied histopathologically at the conclusion of the study. Results. There was no significant drop in IOP after 10 days, using the 0.04% concentration of cidofovir drops. Histology revealed mild corneal edema and inflammatory infiltrate; iris, ciliary body and retina were normal. There was a statistically significant drop in IOP in the eyes treated with 0.4% and 4.0%, cidofovir eye drops at 10 days (p = 0.005 and p < 0.0001, respectively) compared to baseline. Morphological changes included moderate to severe corneal edema, vascularization and inflammatory infiltration. The iris and ciliary body revealed mild inflammatory changes only at the 4% cidofovir dose. No changes were seen in the retina with any doses. No change in IOP was observed following subconjunctival injections of 4% cidofovir, and histologically, only localized inflammatory changes in the conjunctiva were observed. Conclusions. The IOP-decreasing effect of cidofovir occurs at doses below those causing intraocular inflammation and is likely due to an effect on the anterior segment. The anterior segment effects of cidofovir in guinea pigs were similar to those in humans. Thus, the guinea pig appears to be a good animal model for studying the effects of cidofovir on the anterior segment structures. C1 USN Hosp, Dept Ophthalmol & Clin Invest, San Diego, CA 92134 USA. Katholieke Univ Leuven, Rega Inst Med Res, B-3001 Leuven, Belgium. RP Freeman, WR (reprint author), Univ Calif San Diego, Shiley Eye Ctr, Dept Ophthalmol, 9415 Campus Point Dr, La Jolla, CA 92093 USA. FU NEI NIH HHS [EY07366] NR 29 TC 7 Z9 7 U1 0 U2 1 PU AEOLUS PRESS PI BUREN PA PO BOX 740, 4116 ZJ BUREN, NETHERLANDS SN 0271-3683 J9 CURR EYE RES JI Curr. Eye Res. PD JUN PY 1998 VL 17 IS 6 BP 560 EP 566 DI 10.1076/ceyr.17.6.560.5178 PG 7 WC Ophthalmology SC Ophthalmology GA ZT748 UT WOS:000074121200002 PM 9663845 ER PT J AU Ayres, VM McCormick, T Alexander, WB Vestyck, DJ Butler, JE Spiberg, P AF Ayres, VM McCormick, T Alexander, WB Vestyck, DJ Butler, JE Spiberg, P TI Infra-red emission characterization of polycrystalline diamond films SO DIAMOND AND RELATED MATERIALS LA English DT Article; Proceedings Paper CT Diamond 97 Conference CY AUG 03-08, 1997 CL EDINBURGH, SCOTLAND DE infra-red; defect; photoluminescence; Raman spectroscopy ID SPECTROSCOPY; SURFACES AB Infra-red emission has been used to characterize polycrystalline diamond films of differing qualities, produced by de arcjet chemical vapor deposition. Intrinsic and defect-induced bands were observed from samples heated in a low emissivity cell using Fourier Transform Infra-red spectroscopy (FTIR). In addition, the IR emission and absorption spectra of polished IIa and Ib single crystal diamonds were measured to compare the intrinsic and nitrogen-induced absorption and emission bands. Emission features observed included the intrinsic two phonon bands, defect-induced one phonon bands (from symmetry breaking), nitrogen-related bands, and CH stretching bands. Complementary information on the quality and defects in the samples was provided using photoluminescence and Raman spectroscopies. (C) 1998 Elsevier Science S.A. C1 Michigan State Univ, Dept Elect Engn, E Lansing, MI 48824 USA. Harris Semicond Inc, Analyt Serv, Palm Bay, FL 32905 USA. MEMC Elect Mat Inc, St Peters, MO 63376 USA. Geocenters Inc, Ft Washington, MD 20744 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. ECR Corp, San Diego, CA 92121 USA. RP Ayres, VM (reprint author), Michigan State Univ, Dept Elect Engn, 2120 Engn Bldg, E Lansing, MI 48824 USA. EM ayresv@egr.msu.edu RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 8 TC 8 Z9 8 U1 1 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD JUN PY 1998 VL 7 IS 6 BP 789 EP 793 DI 10.1016/S0925-9635(97)00320-8 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA ZT963 UT WOS:000074146200013 ER PT J AU Wu, F Chen, LG Wu, C Sun, FG AF Wu, F Chen, LG Wu, C Sun, FG TI Optimum performance of irreversible stirling engine with imperfect regeneration SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE stirling cycle; imperfect regeneration; heat transfer; optimal efficiency ID FINITE-TIME; POWER OPTIMIZATION; THERMODYNAMICS AB An optimal performance analysis is performed for a Stirling engine with heat transfer ana imperfect regeneration irreversibilities. The relationship between the net power output and thermal efficiency of the engine is derived. Detailed numerical examples are given. The results obtained in this paper provide guidance to performance evaluation and design improvement for Stirling engines. Published by Elsevier Science Ltd. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. USN, Acad Engn, Fac 306, Wuhan 430033, Peoples R China. RP Wu, C (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. NR 13 TC 44 Z9 53 U1 3 U2 12 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 JUN PY 1998 VL 39 IS 8 BP 727 EP 732 DI 10.1016/S0196-8904(97)10036-X PG 6 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA ZC367 UT WOS:000072570800003 ER PT J AU Wu, F Chen, L Sun, F Wu, C Zhu, YH AF Wu, F Chen, L Sun, F Wu, C Zhu, YH TI Performance and optimization criteria for forward and reverse quantum stirling cycles SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE harmonic oscillators; quantum; stirling cycle; finite-time thermodynamics; nonequilibrium statistical mechanics ID FINITE-TIME THERMODYNAMICS; HEAT ENGINE; AMPLIFIER; MODEL AB The optimal performance for forward and reverse quantum Stirling cycles is studied in this paper. The finite time thermodynamic performance bound and optimization criteria for these cycles are derived. The optimal relations between the performance parameters for quantum Stirling engines, refrigerators and heat pumps are obtained. Published by Elsevier Science Ltd. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. USN, Acad Engn, Fac 307, Wuhan 430033, Peoples R China. Wuhan Inst Chem Technol, Dept Mech Engn, Wuhan 430073, Peoples R China. RP Wu, C (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. NR 19 TC 44 Z9 53 U1 0 U2 3 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 JUN PY 1998 VL 39 IS 8 BP 733 EP 739 DI 10.1016/S0196-8904(97)10037-1 PG 7 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA ZC367 UT WOS:000072570800004 ER PT J AU Chen, LG Sun, FR Ni, N Wu, C AF Chen, LG Sun, FR Ni, N Wu, C TI Optimal configuration of a class of two-heat-reservoir refrigeration cycles SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE fixed-temperature heat reservoirs; carnot refrigeration cycles; cooling load ID FINITE-TIME THERMODYNAMICS; GENERALIZED CARNOT CYCLE; MAXIMUM POWER; WORKING FLUID; ENGINES; OPTIMIZATION; PERFORMANCE; EFFICIENCY; OUTPUT AB The optimal coefficient of performance (COP) of a class of two-heat-reservoir refrigeration cycles can be determined by a given cycle time and absorbed heat (cooling load) with consideration of heat leak, finite heat capacity low-temperature source and infinite heat capacity high-temperature heat sink. The refrigeration cycles considered in this paper include (1) infinite low-and high-temperature reservoirs without heat leak, (2) infinite low-and high-temperature reservoirs with heat leak, (3) finite low-temperature source and infinite high-temperature sink without heat leak, and (4) finite low-temperature source and infinite high-temperature sink with heat leak. It is assumed that the heat transfer between the working fluid and the reservoirs obeys Newton's law. It is shown that the existence of the heat leak does not affect the optimal configuration of a cycle with an infinite low-temperature source. The finite heat capacity of a low temperature source without heat leak makes the cycle a generalized Carnot refrigeration cycle. There exists a great difference of the cycle configurations for the finite low temperature source with heat leak and the former three cases. Moreover, the relations between the optimal cooling load and the COP of the former three configurations are derived, and they show that the heat leak affects the cooling load versus COP characteristics of the refrigeration cycles. Published by Elsevier Science Ltd. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. USN, Fac 306, Acad Engn, Wuhan 430033, Peoples R China. RP Wu, C (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. EM wu@artic.nadn.navy.mil NR 39 TC 17 Z9 19 U1 0 U2 0 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 JUN PY 1998 VL 39 IS 8 BP 767 EP 773 DI 10.1016/S0196-8904(97)10026-7 PG 7 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA ZC367 UT WOS:000072570800008 ER PT J AU Su, XZ Carucci, DJ Wellems, TE AF Su, XZ Carucci, DJ Wellems, TE TI Plasmodium falciparum: Parasite typing by using a multicopy microsatellite marker, PfRRM SO EXPERIMENTAL PARASITOLOGY LA English DT Article DE Malaria; genetic diversity; simple sequence length polymorphisms; interspersed repetitive elements; genetic fingerprinting ID DNA C1 NIAID, LPD, NIH, Bethesda, MD 20892 USA. USN, Med Res Inst, Rockville, MD 20852 USA. RP Su, XZ (reprint author), NIAID, LPD, NIH, Bldg 4,Room 126, Bethesda, MD 20892 USA. EM xsu@helix.nih.gov OI Su, Xinzhuan/0000-0003-3246-3248 NR 14 TC 38 Z9 39 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0014-4894 J9 EXP PARASITOL JI Exp. Parasitol. PD JUN PY 1998 VL 89 IS 2 BP 262 EP 265 DI 10.1006/expr.1998.4299 PG 4 WC Parasitology SC Parasitology GA ZT861 UT WOS:000074135600015 PM 9635451 ER PT J AU Love, RW AF Love, RW TI When allies differ: Anglo-American relations during the Suez and Falkland Crises. SO HISTORIAN LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Love, RW (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU PHI ALPHA THETA PI ALLENTOWN PA THE HISTORIAN 50 COLLEGE DR, ALLENTOWN, PA 18104-6100 USA SN 0018-2370 J9 HISTORIAN JI Historian PD SUM PY 1998 VL 60 IS 4 BP 872 EP 873 PG 2 WC History SC History GA 106EE UT WOS:000075116300037 ER PT J AU Quartararo, AT AF Quartararo, AT TI Soldier-scholars: Higher education in the AEF, 1917-1919. SO HISTORY OF EDUCATION QUARTERLY LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Quartararo, AT (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU HISTORY EDUCATION SOC PI SLIPPERY ROCK PA 220 MCKAY EDUCATION BLDG, SLIPPERY ROCK UNIV, SLIPPERY ROCK, PA 16057-1326 USA SN 0018-2680 J9 HIST EDUC QUART JI Hist. Educ. Q. PD SUM PY 1998 VL 38 IS 2 BP 195 EP 197 DI 10.2307/369989 PG 3 WC Education & Educational Research; History Of Social Sciences SC Education & Educational Research; Social Sciences - Other Topics GA 145ZU UT WOS:000077403400007 ER PT J AU Rochin, JAG Roderick, A AF Rochin, JAG Roderick, A TI Aircraft Stores Interface Manual (ASIM) adopts Paperless Information Technology SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB During recent years, defense budgets have been cut across all services while the cost of maintaining current standards has risen. The Aircraft Stores interface Manual (ASIM) Program Office found that maintaining a staff for paper updates was no longer feasible and was tasked by the North Atlantic Treaty Organization (NATO) Air Armament Working Party (AAWP) to digitize the ASIM manuals. Converting this information from paper to electronic media presented several challenges which are discussed. Adopting Paperless Information Technology and replacing "Snail Mail" with the World Wide Web is presented. C1 USN, NAWCWPNSDIV, Point Mugu, CA 93042 USA. Comarco Inc, Camarillo, CA 93010 USA. RP Rochin, JAG (reprint author), USN, NAWCWPNSDIV, Point Mugu, CA 93042 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD JUN PY 1998 VL 13 IS 6 BP 39 EP 43 DI 10.1109/62.683730 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA ZR971 UT WOS:000074034700007 ER PT J AU Ding, YJJ Kang, JU Khurgin, JB AF Ding, YJJ Kang, JU Khurgin, JB TI Theory of backward second-harmonic and third-harmonic generation using laser pulses in quasi-phase-matched second-order nonlinear medium SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE frequency conversion; harmonic generation; nonlinear media; nonlinear optics; nonlinear wave propagation; periodic structures ID LIMITED FUNDAMENTAL PULSES; 2ND-HARMONIC GENERATION; WAVE-GUIDES; SEMICONDUCTOR-LASER; QUANTUM-WELLS; BLUE-LIGHT; FREQUENCY; GREEN; GAAS AB Recently, we have observed backward second-harmonic generation (SHG) using subpicosecond and nanosecond laser pulses in periodically poled lithium niobate crystals, The conversion efficiency in terms of energy density per pulse measured in the experiments agrees weal with that based on our theory. In this paper, we present our theoretical investigation of this process in detail, Although the temporal behaviors of the second-harmonic radiation are determined by the saline functions as those for the forward SHG, the amounts of pulse broadening and conversion efficiencies are quite different for the two configurations. In addition, we have investigated saturation of the conversion efficiencies. We have also considered effective third-harmonic generation based on cascaded second-order nonlinear processes, For a few optimized spatial periods of the domains, we have estimated the conversion efficiencies. C1 Bowling Green State Univ, Ctr Mat, Dept Phys & Astron, Bowling Green, OH 43403 USA. Bowling Green State Univ, Ctr Photochem Sci, Bowling Green, OH 43403 USA. Johns Hopkins Univ, Dept Elect & Comp Engn, Baltimore, MD 21218 USA. USN, Res Lab, Washington, DC 20375 USA. RP Ding, YJJ (reprint author), Bowling Green State Univ, Ctr Mat, Dept Phys & Astron, Bowling Green, OH 43403 USA. RI Kang, Jin/A-3228-2010; khurgin, Jacob/A-3278-2010 NR 34 TC 23 Z9 23 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD JUN PY 1998 VL 34 IS 6 BP 966 EP 974 DI 10.1109/3.678592 PG 9 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZP196 UT WOS:000073727300005 ER PT J AU Rabinovich, WS Beadie, G Katzer, DS AF Rabinovich, WS Beadie, G Katzer, DS TI Intersubband chi(3) in coupled InGaAs-AlGaAs multiple quantum wells SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE infrared spectroscopy; nonlinear optics; optical planar waveguide components; optical saturation; optical switches; quantum-well devices ID 3RD-ORDER NONLINEARITIES; REFRACTIVE-INDEX; MU-M; TRANSITIONS; GAAS; GLASS; PHASE AB The third-order nonlinearity, chi(3)(omega,omega,-omega), is measured for a mid-infrared intersubband transition in strained InGaAs-AlGaAs multiple quantum wells (MQW's), The high conduction band offset of this system allows an intersubband transition at 3.1 mu m. The level structure of the quantum well is designed to include a meta-stable trapping level, resulting in a peak saturation intensity of 6 MW/cm(2) at Brewster's angle, approximately 20 times lower than would be found in a square quantum well with similar linewidth. A near-resonant n(2) of 8.4 x 10(-7) cm(2)/W at 3.1 mu m is calculated, The off-resonant n(2) is also calculated and shown to be attractive at wavelengths as short as 1.55 mu m. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rabinovich, WS (reprint author), USN, Res Lab, Code 5642, Washington, DC 20375 USA. RI Katzer, D. Scott/N-7841-2013 NR 27 TC 11 Z9 11 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD JUN PY 1998 VL 34 IS 6 BP 975 EP 981 DI 10.1109/3.678593 PG 7 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZP196 UT WOS:000073727300006 ER PT J AU McGee, KJ AF McGee, KJ TI Comments on "A 64-point Fourier transform chip for video motion compensation using phase correlation"' SO IEEE JOURNAL OF SOLID-STATE CIRCUITS LA English DT Letter C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. RP McGee, KJ (reprint author), 33 Everett St, Newport, RI 02840 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9200 J9 IEEE J SOLID-ST CIRC JI IEEE J. Solid-State Circuit PD JUN PY 1998 VL 33 IS 6 BP 928 EP 932 DI 10.1109/JSSC.1998.678993 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA ZP765 UT WOS:000073786200014 ER PT J AU Koplow, JP Goldberg, L Kliner, DAV AF Koplow, JP Goldberg, L Kliner, DAV TI Compact 1-W Yb-doped double-cladding fiber amplifier using V-groove side-pumping SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE optical fiber amplifiers; optical fiber devices; ytterbium ID LASER; OPERATION AB A compact packaged fiber amplifier was constructed using a Yb-doped double-cladding fiber, which was V-groove side-pumped by a laser diode operating at 975 nm, Under saturation, the amplifier generated 1 W at 1064 nm, The small-signal gain reached a maximum of 50 dB at 1075 nm and was greater than 40 dB in the range of 1042-1093 nm. 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 12 TC 21 Z9 22 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 JUN PY 1998 VL 10 IS 6 BP 793 EP 795 DI 10.1109/68.681486 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZN391 UT WOS:000073641200015 ER PT J AU Burns, WK Howerton, MM Moeller, RP Greenblatt, AS McElhanon, RW AF Burns, WK Howerton, MM Moeller, RP Greenblatt, AS McElhanon, RW TI Broad-band reflection traveling-wave LiNbO3 modulator SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE integrated optics; microwave modulation; modulation; optical modulation; optical interferometry AB A velocity matched traveling-wave Mach-Zehnder interferometer (MZI) in LiNbO3, operating in reflection, is reported and drive voltages are compared to those for single-pass devices of the same length. The device achieves double-pass operation by simultaneously reflecting the optical and RF waves. Broad-band operation to 20 GHz with drive voltages from 0.5 to 1 V (<0.5 GHz) to similar to 4.5 V (at 20 GHz) is observed with the reflection device. This performance is superior to that of the single-pass device, which has drive voltages of 2.1 V (dc) to similar to 4.5 V (at 20 GHz). C1 USN, Res Lab, Code 5671, Washington, DC 20375 USA. SFA Inc, Largo, MD 20774 USA. RP Burns, WK (reprint author), USN, Res Lab, Code 5671, Washington, DC 20375 USA. NR 5 TC 19 Z9 19 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 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD JUN PY 1998 VL 10 IS 6 BP 805 EP 806 DI 10.1109/68.681490 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZN391 UT WOS:000073641200019 ER PT J AU Carroll, TL Pecora, LM AF Carroll, TL Pecora, LM TI Synchronizing hyperchaotic volume-preserving maps and circuits SO IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-FUNDAMENTAL THEORY AND APPLICATIONS LA English DT Article DE chaos; synchronization ID COMMUNICATION; SYSTEMS; SIGNALS; CHAOS AB We show that it is possible to synthesize chaotic systems that have improved characteristics for use in communications. These include whiter spectrum, low-time correlation, hyperchaotic behavior, and little or no phase space structure. These systems are based on locally volume-preserving (or expanding) maps. We show how to construct a circuit that produces such characteristics. C1 USN, Res Lab, Washington, DC 20375 USA. RP Carroll, TL (reprint author), USN, Res Lab, Washington, DC 20375 USA. OI Carroll, Thomas/0000-0002-2371-2049 NR 17 TC 25 Z9 25 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 1057-7122 J9 IEEE T CIRCUITS-I JI IEEE Trans. Circuits Syst. I-Fundam. Theor. Appl. PD JUN PY 1998 VL 45 IS 6 BP 656 EP 659 DI 10.1109/81.678482 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA ZR788 UT WOS:000074013800006 ER PT J AU Hicks, CW Hwang, HS Steer, MB Mink, JW Harvey, JF AF Hicks, CW Hwang, HS Steer, MB Mink, JW Harvey, JF TI Spatial power combining for two-dimensional structures SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article; Proceedings Paper CT 1997 Topical Symposium on Millimeter Waves CY JUL 07-08, 1997 CL SHONAN VILLAGE CTR, HAYAMA, JAPAN SP USAF, Off Sci Res, IEEE, Microwave Theory & Techn Soc HO SHONAN VILLAGE CTR DE power combining ID WAVE-GUIDE AB The two-dimensional (2-D) hybrid dielectric slab-beam open and closed waveguide systems are suitable for the design of planar quasi-optical integrated circuits and devices. An open system consisting of an active E-plane amplifier array consisting of Vivaldi-type antennas with MESFET and monolithic microwave integrated circuit (MMIC) devices was investigated. The 4 x 1 MESFET amplifier array generated 11 and 4.5 dB of amplifier and system gain, respectively, at 7.12 GHz, and the cascade MMIC Vivaldi-type antenna produced 24 dB of amplifier gain at 8.4 GHz, Also, experiments on a new 2-D H-plane parallel-plate closed system with a stripline slot antenna is introduced, and the wavebeam-mode theory is presented. The new system minimizes scattering and isolation losses associated with open structures. The amplifier gain of the closed system based on slot antennas is compared to the open system based on Vivaldi antennas. C1 N Carolina State Univ, Dept Elect & Comp Engn, Ctr Adv Comp & Commun, Raleigh, NC 27695 USA. USN, Air Warfare Ctr, Div Aircraft, Patuxent River, MD 20670 USA. USA, Res Off, Div Elect, Res Triangle Pk, NC 27709 USA. RP Hicks, CW (reprint author), N Carolina State Univ, Dept Elect & Comp Engn, Ctr Adv Comp & Commun, Raleigh, NC 27695 USA. NR 8 TC 7 Z9 7 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD JUN PY 1998 VL 46 IS 6 BP 784 EP 791 DI 10.1109/22.681201 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA ZQ886 UT WOS:000073912900010 ER PT J AU Kurfess, JD AF Kurfess, JD TI Compton scatter imaging in astrophysics SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 1997 Nuclear Science Symposium CY NOV 09-15, 1997 CL ALBUQUERQUE, NEW MEXICO ID GAMMA-RAY ASTRONOMY; NUCLEAR ASTROPHYSICS; TELESCOPE; INSTRUMENT; MISSION AB Compton telescopes have been an important tool in gamma-ray astronomy, most recently with the COMPTEL instrument on NASA's COMPTON Gamma Ray Observatory (CGRO). Scientific objectives in low/medium energy gamma-ray astronomy place highest priority on significant improvement in sensitivity relative to CGRO and ESA's planned INTEGRAL mission. The observational requirements include both discrete and extended sources, and narrow, broad, and continuum spectral features, A high spectral and spatial resolution Compton telescope is the preferred instrument for a future mission. The broad range of scientific objectives that such a mission will address include: mapping radioactivity across the Galaxy (Al-26, Ti-44, Fe-60), detection of several Type Ia supernovae per year (Ni-56, (CO)-C-56), study nuclear burning in novae (Na-22, Be-7, 511 keV), study the accretion of matter onto galactic and massive extra-galactic black holes and the associated formation of relativistic jets, and provide unique insights into neutron stars, cosmic gamma-ray bursts, and solar flares. A mission to achieve these goals should have discrete source, narrow line sensitivities approaching 10(-7) gamma/cm(2)-s for the important astrophysical gamma-ray Lines from 511 keV to 2 MeV. Detectors which combine state-of-the-art energy resolution (few keV) and spatial resolution (1 mm) are required. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kurfess, JD (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 14 TC 3 Z9 3 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 1998 VL 45 IS 3 BP 936 EP 942 DI 10.1109/23.682676 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA ZU096 UT WOS:000074161200136 ER PT J AU Pease, RL Shaneyfelt, M Winokur, P Fleetwood, D Gorelick, J McClure, S Clark, S Cohn, L Alexander, D AF Pease, RL Shaneyfelt, M Winokur, P Fleetwood, D Gorelick, J McClure, S Clark, S Cohn, L Alexander, D TI Mechanisms for total dose sensitivity to preirradiation thermal stress in bipolar linear microcircuits SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 4th European Conference on Radiation and its Effects on Components and Systems (RADECS 97) CY SEP 15-19, 1997 CL CANNES, FRANCE SP Thomson CSF, Aerospatiale Espace & Def, TEMIC Semiconductors, CEA/DAM, Ministere Culture, Sandia Natl Labs ID IONIZING-RADIATION; BURN-IN; DEGRADATION AB The ionizing radiation response of several semiconductor process technologies has been shown to be affected by preirradiation thermal stress. Data on bipolar linear circuits are presented and discussed in terms of the mechanisms previously proposed for CMOS. C1 RLP Res, Albuquerque, NM 87122 USA. Sandia Natl Labs, Albuquerque, NM 87131 USA. Hughes Space & Commun, Los Angeles, CA 90009 USA. USN, Ctr Surface Warfare, Crane, IN 47522 USA. Def Special Weap Agcy, Alexandria, VA 22003 USA. Mission Res Corp, Albuquerque, NM 87106 USA. RP Pease, RL (reprint author), RLP Res, Albuquerque, NM 87122 USA. NR 17 TC 19 Z9 19 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 1998 VL 45 IS 3 BP 1425 EP 1430 DI 10.1109/23.685218 PN 3 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA ZU365 UT WOS:000074189800014 ER PT J AU Melinger, JS McMorrow, D Buchner, S Knudson, AR Tran, LH Campbell, AB AF Melinger, JS McMorrow, D Buchner, S Knudson, AR Tran, LH Campbell, AB TI Investigations of single-event upsets and charge collection in micro-electronics using variable-length laser-generated charge tracks SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 4th European Conference on Radiation and its Effects on Components and Systems (RADECS 97) CY SEP 15-19, 1997 CL CANNES, FRANCE SP Thomson CSF, Aerospatiale Espace & Def, TEMIC Semiconductors, CEA/DAM, Ministere Culture, Sandia Natl Labs ID GAAS-MESFETS; PULSED-LASER; DEPENDENCE; DYNAMICS; SEU AB In this paper we examine how single-event upsets (SEU) and related charge collection characteristics in micro-electronic circuits and devices depend on the depth of charge deposited by a picosecond laser pulse. Charge tracks of variable length are generated by tuning the laser wavelength through the semiconductor absorption spectrum. Our results show that the variable-length charge tracks provide a unique and sensitive probe of the charge collection volume of a micro-electronic circuit/device. In favorable cases we show how the wavelength tunability of the laser can be used to provide an experimental estimate of the charge collection depth. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Landover, MD 20785 USA. RP Melinger, JS (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 21 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 1998 VL 45 IS 3 BP 1487 EP 1493 DI 10.1109/23.685228 PN 3 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA ZU365 UT WOS:000074189800024 ER PT J AU McMorrow, D Melinger, JS Knudson, AR Buchner, S Tran, LH Campbell, AB Curtice, WR AF McMorrow, D Melinger, JS Knudson, AR Buchner, S Tran, LH Campbell, AB Curtice, WR TI Charge-enhancement mechanisms of GaAs field-effect transistors: Experiment and simulation SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 4th European Conference on Radiation and its Effects on Components and Systems (RADECS 97) CY SEP 15-19, 1997 CL CANNES, FRANCE SP Thomson CSF, Aerospatiale Espace & Def, TEMIC Semiconductors, CEA/DAM, Ministere Culture, Sandia Natl Labs ID BUFFER LAYER; HETEROSTRUCTURE FETS; TEMPERATURE MODEL; COLLECTION; MESFETS; DEVICES AB The charge-collection processes of GaAs field-effect transistors are investigated as a function of the incident laser pulse energy via time-resolved charge-collection measurements and by two-dimensional computer simulation. The measurements and simulations reveal a feature that persists on a time scale of 100 ps, the amplitude of which varies strongly with the injected carrier density (pulse energy). The appearance of this feature is associated with a barrier lowering effect at the source/substrate junction, coupled with the drift-assisted transport of electrons through the substrate to the drain contact. This behavior is similar, but not identical to bipolar-gain models that have been suggested previously. We introduce the concept of ion-track segments and illustrate their utility in interrogating the complex mechanisms of charge collection and enhancement in GaAs FETs. C1 USN, Res Lab, Washington, DC 20375 USA. WR Curtice Consulting, Princeton Junction, NJ 08550 USA. RP McMorrow, D (reprint author), USN, Res Lab, Code 6613, Washington, DC 20375 USA. NR 25 TC 19 Z9 19 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 1998 VL 45 IS 3 BP 1494 EP 1500 DI 10.1109/23.685229 PN 3 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA ZU365 UT WOS:000074189800025 ER PT J AU Buchner, S Olmos, M Cheynet, P Velazco, R McMorrow, D Melinger, J Ecoffet, R Muller, JD AF Buchner, S Olmos, M Cheynet, P Velazco, R McMorrow, D Melinger, J Ecoffet, R Muller, JD TI Pulsed laser validation of recovery mechanisms of critical SEE's in an artificial neural network system. SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 4th European Conference on Radiation and its Effects on Components and Systems (RADECS 97) CY SEP 15-19, 1997 CL CANNES, FRANCE SP Thomson CSF, Aerospatiale Espace & Def, TEMIC Semiconductors, CEA/DAM, Ministere Culture, Sandia Natl Labs AB A pulsed laser was used to inject errors into an electronic system consisting of a number of different integrated circuits functioning as a digital version of an artificial neural network. The results confirm that the system as a whole can operate autonomously in the radiation environment of space. Additional work was done to characterize the effects of the upsets on the output of the artificial neural network. C1 USN, Res Lab, SFA Inc, Washington, DC 20375 USA. TIMA Lab, F-38031 Grenoble, France. Ctr Natl Etud Spatiales, CT, AQ, CB, F-31055 Toulouse, France. CEA, DAM, FRIF, DCRE,SEIM, F-91680 Bruyeres Le Chatel, France. RP Buchner, S (reprint author), USN, Res Lab, SFA Inc, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 5 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 1998 VL 45 IS 3 BP 1501 EP 1507 DI 10.1109/23.685230 PN 3 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA ZU365 UT WOS:000074189800026 ER PT J AU Williams, GM Friebele, EJ AF Williams, GM Friebele, EJ TI Space radiation effects on erbium-doped fiber devices: Sources, amplifiers, and passive measurements SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 4th European Conference on Radiation and its Effects on Components and Systems (RADECS 97) CY SEP 15-19, 1997 CL CANNES, FRANCE SP Thomson CSF, Aerospatiale Espace & Def, TEMIC Semiconductors, CEA/DAM, Ministere Culture, Sandia Natl Labs ID OPTICAL FIBERS; ABSORPTION AB Measurements have been made of the effect of gamma-irradiation on the performance of active erbium-doped fiber devices. These include the decrease in optical power of an erbium-doped fiber amplifier (EDFA) and a superluminescent source (SLS), and the shift in centroid wavelength of the SLS with exposure. Calculations have been performed to correlate these effects with the radiation-induced absorption measured passively. Excellent agreement was obtained for the radiation-induced power loss in the EDFA, and good agreement was obtained for the SLS. However, the calculation underestimated the centroid wavelength shift in the SLS by a factor of similar to 3. A model has been developed to extrapolate the results of passive loss measurements to the low dose rates typical of the natural space environment. C1 USN, Res Lab, Washington, DC 20375 USA. Virginia Polytech Inst & State Univ, Dept Elect Engn, Blacksburg, VA 24061 USA. RP Williams, GM (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 21 TC 44 Z9 46 U1 1 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 1998 VL 45 IS 3 BP 1531 EP 1536 DI 10.1109/23.685235 PN 3 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA ZU365 UT WOS:000074189800031 ER PT J AU Campbell, AB Musseau, O Ferlet-Cavrois, V Stapor, WJ McDonald, PT AF Campbell, AB Musseau, O Ferlet-Cavrois, V Stapor, WJ McDonald, PT TI Analysis of single event effects at grazing angle SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 4th European Conference on Radiation and its Effects on Components and Systems (RADECS 97) CY SEP 15-19, 1997 CL CANNES, FRANCE SP Thomson CSF, Aerospatiale Espace & Def, TEMIC Semiconductors, CEA/DAM, Ministere Culture, Sandia Natl Labs ID CHARGE COLLECTION; UPSET; SRAM AB Investigation of single event effects at grazing angle by both charge collection and multiple bit upset measurements evidences modified collection mechanisms with charge transfer between adjacent reverse biased structures. C1 USN, Res Lab, Washington, DC 20375 USA. CEA, Bruyeres Le Chatel, France. ICI, Mclean, VA USA. RP Campbell, AB (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 17 TC 6 Z9 6 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 1998 VL 45 IS 3 BP 1603 EP 1611 DI 10.1109/23.685247 PN 3 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA ZU365 UT WOS:000074189800043 ER PT J AU Blank, M Danly, BG Levush, B Pershing, DE AF Blank, M Danly, BG Levush, B Pershing, DE TI Experimental investigation of W-band (93 GHz) gyroklystron amplifiers SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE gyroklystron; high power amplifier; millimeter wave ID 2ND-HARMONIC GYROKLYSTRON; PERFORMANCE; DESIGN AB The results from W-band gyroklystron amplifier experiments are presented. Two circuit configurations, WGKL1 and WGKL2, have been demonstrated, The WGKL1 circuit achieved 67 kW peak output power, corresponding to 28% efficiency, for a 55-kV, 4.3-A electron beam. The full width half maximum (FWHM) bandwidth was measured to be 460 MHz, a significant increase over the bandwidth demonstrated in previous W-band gyroklystron experiments. The amplifier was unconditionally stable at the operating point. The WGKL2 circuit, which was designed to have a broader bandwidth, produced 60 kW peak output power at 25% efficiency with a 640 MHz FWHM bandwidth for a 58 kV, 4.2 A electron beam, The results from both experiments are compared with theory and good agreement is obtained. C1 USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. Mission Res Corp, Newington, VA 22122 USA. RP Blank, M (reprint author), USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. EM blank@mmace.nrl.navy.mil NR 15 TC 38 Z9 39 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD JUN PY 1998 VL 26 IS 3 BP 409 EP 415 DI 10.1109/27.700772 PG 7 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400025 ER PT J AU Choi, JJ McCurdy, AH Wood, FN Kyser, RH Calame, JP Nguyen, KT Danly, BG Antonsen, TM Levush, B Parker, RK AF Choi, JJ McCurdy, AH Wood, FN Kyser, RH Calame, JP Nguyen, KT Danly, BG Antonsen, TM Levush, B Parker, RK TI Experimental investigation of a high power, two-cavity, 35 GHz gyroklystron amplifier SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE cavity; coherent radiation; electron beam; gyroklystron ID BAND 2ND-HARMONIC GYROKLYSTRON; GYROTRON; DESIGN AB Experiments on a two-cavity gyroklystron amplifier are performed to demonstrate high power coherent radiation amplification at 34.95 GHz, Experiments show a saturated efficiency of 37%, a bandwidth of 0.36%, and a gain of 23.6 dB corresponding to peak radiation output power of 210 kW. Experimental results are in good agreement with large signal simulations. Calculations also show that a stagger-tuned three-cavity circuit increases the bandwidth to more than 0.9%. C1 Kwangwoon Univ, Dept Radio Engn, Seoul, South Korea. Univ So Calif, Los Angeles, CA 90089 USA. DynCorp, Rockville, MD 20850 USA. USN, Res Lab, Washington, DC 20375 USA. KN Res, Silver Spring, MD 20906 USA. Univ Maryland, College Pk, MD 20742 USA. RP Choi, JJ (reprint author), Kwangwoon Univ, Dept Radio Engn, Seoul, South Korea. RI Antonsen, Thomas/D-8791-2017 OI Antonsen, Thomas/0000-0002-2362-2430 NR 20 TC 34 Z9 38 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD JUN PY 1998 VL 26 IS 3 BP 416 EP 425 DI 10.1109/27.700773 PG 10 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400026 ER PT J AU Blank, M Danly, BG Levush, B AF Blank, M Danly, BG Levush, B TI Circuit design of a wideband W-band gyroklystron amplifier for radar applications SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE gyroklystron amplifier; high power amplifiers; millimeter wave radar AB A high power W-band gyroklystron amplifier has been designed as the driver for a millimeter wave radar system currently under development at the Naval Research Laboratory. A time dependent, nonlinear theory was used to design the interaction circuit. Studies to determine the optimal stagger tuning and cavity Q values were performed. Circuit stability was investigated and the effect of beam parameter variation on circuit performance was also studied, The effects of mechanical tolerances and deviation of circuit dimensions from design values were examined. Simulations show that a four cavity circuit operating in the TE(011) mode at the fundamental of the cyclotron frequency can achieve 80.2 kW peak output power and 20.6% efficiency at a center frequency of 94.0 GHz with 740 MHz full width half maximum (FWHM) bandwidth for a 65 kV, 6 A electron beam. C1 USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. RP Blank, M (reprint author), USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. EM blank@mmace.nrl.navy.mil NR 6 TC 13 Z9 15 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD JUN PY 1998 VL 26 IS 3 BP 426 EP 432 DI 10.1109/27.700774 PG 7 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400027 ER PT J AU Garven, M Manheimer, WM Blank, M AF Garven, M Manheimer, WM Blank, M TI Simple theory of input couplers for gyroklystron amplifiers SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE dipole theory; gyroklystron amplifier; input coupler AB This paper formulates and evaluates simple approaches to the input-wave coupling problem in the Naval Research Laboratory (NRL) 94 GHz gyroklystron amplifier. It looks at the hole between the input waveguide and coaxial cavity, as well as the coupling holes between the coaxial cavity and main cavity as a simple dipole. Direct comparisons are made between the dipole theory and simulations using the Maxwell's equations solver high frequency structural simulator (HFSS). The results are in reasonable agreement. Where the theory lacks accuracy as compared to modern field solvers, it may gain in simplicity, speed of operation (both human time and computer time) and analytic insight. C1 Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. RP Garven, M (reprint author), Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. NR 10 TC 7 Z9 11 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD JUN PY 1998 VL 26 IS 3 BP 433 EP 443 DI 10.1109/27.700775 PG 11 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400028 ER PT J AU Antonsen, TM Manheimer, WM AF Antonsen, TM Manheimer, WM TI Shot noise in gyroklystrons SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE electrostatic cyclotron instability; gyroklystron; noise ID SPACE-CHARGE INSTABILITIES; GYROTRON BEAMS; AMPLIFICATION AB Expressions for the shot noise generated in the input cavity of a gyroklystron are calculated. Results are given for noise amplitude, noise temperature, and phase noise. For a beam of uncorrelated electrons the noise temperature scales as the beam energy. An estimate of the role of collective effects on the noise properties is given, These might either decrease or increase the noise level. It is expected that the shot noise in an actual device will depend in a sensitive way on the profile of magnetic field in the compression region preceding the input cavity. C1 USN, Res Lab, Washington, DC 20375 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. RP Antonsen, TM (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Antonsen, Thomas/D-8791-2017 OI Antonsen, Thomas/0000-0002-2362-2430 NR 16 TC 15 Z9 15 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 JUN PY 1998 VL 26 IS 3 BP 444 EP 450 DI 10.1109/27.700776 PG 7 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400029 ER PT J AU Nusinovich, GS Levush, B Danly, BG AF Nusinovich, GS Levush, B Danly, BG TI Theory of multibeam stagger-tuned gyroklystrons SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE bandwidth; gain; gyroklystron; stagger-tuning ID GYROTRONS AB An analytical theory describing the tradeoff in the bandwidth and gain in multibeam stagger-tuned gyroklystrons (GKL's) is developed. A two-stage multibeam configuration (i.e., the device consisting only of input and output cavities) is considered in detail. The analysis of two-, three-and four-beam configurations allows one to evaluate the increase in bandwidth due to multibeam configuration and the tradeoff in the bandwidth and gain due to the stagger tuning. C1 Omega P, New Haven, CT 06520 USA. Univ Maryland, College Pk, MD 20742 USA. USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. RP Nusinovich, GS (reprint author), Omega P, New Haven, CT 06520 USA. NR 13 TC 3 Z9 3 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 JUN PY 1998 VL 26 IS 3 BP 475 EP 481 DI 10.1109/27.700780 PG 7 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400033 ER PT J AU Blank, M Zasypkin, EV Levush, B AF Blank, M Zasypkin, EV Levush, B TI An investigation of X-band gyrotwystron amplifiers SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE broad-band millimeter-wave amplifier; gyro-amplifier; gyrotwystron ID PERFORMANCE; DESIGN AB Experimental and theoretical studies of the cyclotron maser instability in the gyrotwystron configuration have been made. Several configurations of a three-stage TE0.1 mode X-band gyrotwystron with variable buncher cavity lengths, drift lengths, and output sections, have been tested. An efficiency in excess of 27.5% and a full-width half-maximum (FWHM) bandwidth of 1.6% have been demonstrated for a 16-kV, 1-A electron beam. This bandwidth represents a substantial improvement of over the 1% bandwidth measured for a three-cavity gyroklystron cavity employing the same input and buncher cavities, Experimental results from three gyrotwystron configurations have been compared with predictions of theory and good agreement was obtained. The effect of velocity spread on efficiency and bandwidth was also studied, The favorable comparison of experimental and theoretical data indicates that the model is a useful tool in the design and analysis of gyrotwystron amplifiers. C1 USN, Res Lab, Washington, DC 20375 USA. Russian Acad Sci, Inst Appl Phys, Nizhnii Novgorod 603600, Russia. RP Blank, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 14 TC 3 Z9 3 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 JUN PY 1998 VL 26 IS 3 BP 577 EP 581 DI 10.1109/27.700794 PG 5 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400047 ER PT J AU Abe, DK Carmel, Y Miller, SM Bromborsky, A Levush, B Antonsen, TM Destler, WW AF Abe, DK Carmel, Y Miller, SM Bromborsky, A Levush, B Antonsen, TM Destler, WW TI Experimental studies of overmoded relativistic backward-wave oscillators SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE backward-wave oscillator (BWO); high-power microwave (HPM); overmoded ID CUTOFF AB Internal field-emission breakdown in the electrodynamic structures of high-power microwave (HPM) devices can seriously limit the device's output power and pulse duration. Increasing the diameter of the electrodynamic structure to several times an electromagnetic wavelength can reduce these internal fields to below critical breakdown levels, but may introduce mode competition as an unwanted side effect. This paper presents the design and results of experiments with overmoded (D/lambda similar to 3), sinusoidally corrugated backward-wave oscillators (BWO's) that successfully produced TM0.1.; high-power microwave radiation in the frequency range of 5.2-5.7 GHz. Overmoded BWO's reproducibly generated similar to 200 MW of peak power with corresponding efficiencies of similar to 4%, Pulse shortening was not observed in any of the experiments. The radiation generated by the devices was highly coherent (typically, Delta f/f < 0.5%) and corresponded to a fundamental TR0.1.-mode interaction, The experimental results were compared with calculations made with recently developed nonlinear models; the measured data are shown to agree favorably with theory. The results of the experiments and modeling demonstrate that overmoded electrodynamic structures can be used to decrease internal electric field stresses while avoiding multimode generation and maintaining good spectral purity. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. ENSCO, Springfield, VA 22150 USA. USA, Res Lab, Adelphi, MD 20783 USA. RP Abe, DK (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Abe, David/D-7546-2013; Antonsen, Thomas/D-8791-2017 OI Antonsen, Thomas/0000-0002-2362-2430 NR 16 TC 29 Z9 36 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD JUN PY 1998 VL 26 IS 3 BP 591 EP 604 DI 10.1109/27.700796 PG 14 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400049 ER PT J AU Antonsen, TM Levush, B AF Antonsen, TM Levush, B TI Traveling-wave tube devices with nonlinear dielectric elements SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE electronic tuning; intermodulation distortion; nonlinear dielectric; traveling-wave amplifier ID MICROWAVE AB The performance of traveling-wave tube (TWT) amplifiers incorporating nonlinear dielectric elements is studied via computer simulation. Two different situations are investigated: 1) the use of nonlinear dielectric elements to reduce intermodulation distortion and 2) the use of voltage controlled dielectrics to provide rapid modification of the dispersion characteristics of the slow-wave structure. In the first case, the use of dielectrics with negative second-order susceptibilities is studied as a means of reducing phase and intermodulation distortion, Use of these dielectrics along with dynamic velocity taper to reduce amplitude modulation distortion results in marked reduction of predicted intermodulation distortion. In the second case, the goal is to design an amplifying structure whose gain as a function of frequency can be varied electrically. Preliminary design studies show that relatively large changes in the center frequency of the amplification band can be achieved with relatively modest changes in the dielectric constant of helix support structure. C1 USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. RP Antonsen, TM (reprint author), USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. RI Antonsen, Thomas/D-8791-2017 OI Antonsen, Thomas/0000-0002-2362-2430 NR 17 TC 49 Z9 49 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 JUN PY 1998 VL 26 IS 3 BP 774 EP 786 DI 10.1109/27.700830 PG 13 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400064 ER PT J AU Jin, JG Park, GS Uhm, HS AF Jin, JG Park, GS Uhm, HS TI Propagation characteristics of a premodulated electron beam SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE electron beam; premodulation ID CONSISTENT NONLINEAR-THEORY AB The propagation properties of an electron beam whose energy and current are simultaneously premodulated at the cathode are investigated by computer simulation using the two-dimensional (2-D) particle-in-cell code, MAGIC. The simulation is carried out to investigate the influence of the initial energy modulation and the phase difference between current and energy modulation, With appropriate initial energy modulation, the amplitude of the downstream current modulation can be kept as high as the initial modulation level. Appreciable growth of high harmonic components is also observed as the electron beam debunches. The simulation data are compared with results obtained from a nonlinear theory of the current modulation in an electron beam propagating through a drift tube, It is shown that the simulation data agree remarkably well with the analytical theory. C1 Seoul Natl Univ, Dept Educ Phys, Plasma & Microwave Labs, Seoul 151742, South Korea. USN, Ctr Surface Warfare, W Bethesda, MD 20817 USA. RP Jin, JG (reprint author), Seoul Natl Univ, Dept Educ Phys, Plasma & Microwave Labs, Seoul 151742, South Korea. RI Park, Gunsik/A-1415-2014 NR 10 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 JUN PY 1998 VL 26 IS 3 BP 794 EP 798 DI 10.1109/27.700835 PG 5 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400066 ER PT J AU Nguyen, KT Danly, BG Levush, B Blank, M True, R Good, GR Hargreaves, TA Felch, K Borchard, P AF Nguyen, KT Danly, BG Levush, B Blank, M True, R Good, GR Hargreaves, TA Felch, K Borchard, P TI Electron gun and collector design for 94-GHz gyro-amplifiers SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE beam collector; electron gun; gyro-amplifiers; magnetron injection gun ID ORBIT GYROTRONS AB This paper presents the electrical design of a magnetron injection gun and collector for high peak and average power TE01 W-band gyro-amplifiers, The magnetron injection gun design employs an optimized double-anode geometry and a cathode angle of 50 degrees to achieve superior beam optics that are relatively insensitive to electrode misalignments and field errors. A transverse relative velocity spread of 1.6% at a velocity ratio of 1.5 is obtained in simulations for a 6-A 65-kV beam. Cathode edge emission was modeled, found to produce a major effect on velocity spread, and will be eliminated by nonemissive cylinders affixed to the cathode. The collector, which also serves as the output waveguide, is designed to minimize the required collector length while avoiding eccessive power loading on the collector surface. An average power density of less than 640 W/cm(2) on a 3.25-cm-diameter collector is achieved for 91-kW average beam power. Both the gun and collector are currently under construction. C1 KN Res, Silver Spring, MD 20906 USA. USN, Res Lab, Washington, DC 20375 USA. Litton Electron Devices Div, San Carlos, CA 94070 USA. Commun & Power Ind, Palo Alto, CA 94304 USA. RP Nguyen, KT (reprint author), KN Res, Silver Spring, MD 20906 USA. NR 18 TC 24 Z9 29 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 JUN PY 1998 VL 26 IS 3 BP 799 EP 813 DI 10.1109/27.700837 PG 15 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400067 ER PT J AU Botton, M Antonsen, TM Levush, B Nguyen, KT Vlasov, AN AF Botton, M Antonsen, TM Levush, B Nguyen, KT Vlasov, AN TI MAGY: A time-dependent code for simulation of slow and fast microwave sources SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE fast-wave devices; numerical simulations; particle-in-cell ID POWER GYROTRON OSCILLATORS AB We present the newly developed Maryland Gyrotron (MAGY) code for modeling of slow and fast microwave sources. The code includes a time-dependent description of the electromagnetic fields and a self-consistent analysis of the electrons. The calculations of the electromagnetic fields are based on the waveguide modal representation, which allows the solution of a relatively small number of coupled one-dimensional partial differential equations for the amplitudes of the modes, instead of the full solution of Maxwell's equations. Moreover, the basic time scale for updating the electromagnetic fields is the cavity fill time and not the high frequency of the fields. The equations of motion of the electrons are formulated within the framework of the guiding-center approximation and solved with the electromagnetic fields as the driving forces. Therefore, at each time step, a set of trajectories are calculated and used as current sources for the fields. We present two examples for the operation of the code, namely the two-cavity gyroklystron and the backward-wave oscillator (BWO), These examples demonstrate the possible usage of the code for a wide variety of electron-beam systems. C1 Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. KN Res, Silver Spring, MD 20906 USA. RP Botton, M (reprint author), Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. EM antonsen@glue.umd.edu RI Antonsen, Thomas/D-8791-2017 OI Antonsen, Thomas/0000-0002-2362-2430 NR 16 TC 137 Z9 141 U1 1 U2 12 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD JUN PY 1998 VL 26 IS 3 BP 882 EP 892 DI 10.1109/27.700860 PG 11 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400076 ER PT J AU Whaley, DR Armstrong, CM Gannon, B Groshart, G Hurt, E Hutchins, J Roscoe, M Antonsen, TM Levush, B AF Whaley, DR Armstrong, CM Gannon, B Groshart, G Hurt, E Hutchins, J Roscoe, M Antonsen, TM Levush, B TI Sixty-percent-efficient miniature C-Band vacuum power booster for the microwave power module SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on High Power Microwave (HPM) Generation and Pulse Shortening CY JUN 10-12, 1997 CL EDINBURGH, SCOTLAND DE microwave power module; traveling wave tube; vacuum electron device AB Results from a high-efficiency miniaturized C-Band vacuum power booster (VPB) development program have resulted in the development of a miniature C-Band traveling wave tube (TWT) operating at 32% circuit efficiency and 61% total efficiency at an output power in excess of 170 W at 100% duty factor. When combined with a microwave power module, this VPB results in a module DC-to-RF conversion efficiency of 51%, This high-efficiency power amplifier is particularly well suited for space and airborne applications where;small size, light weight, and low thermal dissipation are required. Other parallel development of VPB's operating at lower perveance and higher power has also been pursued and has resulted in nearly identical performance of 32% circuit efficiency and 61% total efficiency at power levels in excess of 240 W at 100% duty factor. A new TWT interaction code, CHRISTINE, is benchmarked with experimental data from several of these VPB's. Simulated performance is seen to accurately predict experimental data. C1 Northrop Grumman Corp, Elect & Syst Integrat Div, Rolling Meadows, IL 60008 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. Univ Maryland, Inst Plasma Res, Dept Elect Engn, College Pk, MD 20742 USA. Univ Maryland, Inst Plasma Res, Dept Phys, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. RP Whaley, DR (reprint author), Northrop Grumman Corp, Elect & Syst Integrat Div, Rolling Meadows, IL 60008 USA. RI Antonsen, Thomas/D-8791-2017 OI Antonsen, Thomas/0000-0002-2362-2430 NR 13 TC 25 Z9 27 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD JUN PY 1998 VL 26 IS 3 BP 912 EP 921 DI 10.1109/27.700870 PG 10 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400080 ER PT J AU Mosher, D Qi, NS Krishnan, M AF Mosher, D Qi, NS Krishnan, M TI A two-level model for K-Shell radiation scaling of the imploding z-pinch plasma radiation source SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE implosion simulations; K-shell X rays; plasma radiation sources; z-pinch plasmas ID X-RAY-EMISSION; ATOMIC-NUMBER; IMPLOSIONS; GENERATORS AB A simple, first-principle treatment is presented for estimating, within about a factor-of-two, how K-shell x-radiation from the plasma radiation source scales with plasma, pulsed-power, and imploding-load parameters. The transparency of this two-level model clarifies the relations between X-ray yield and underlying physical processes, provides simple analytic expressions for optimal load parameters and associated yields, and establishes links between radiating-load performance and system constraints imposed by other processes. The two-level model provides results similar to another one-zone model based on phenomenological extrapolations of selected one-dimensional radiation-hydrodynamic calculations. The model compares well with K-shell radiation results from Hawk neon gas puff and Saturn aluminum large-wire-number array experiments, provided that assumed compression ratios are less than those inferred from X-ray pinhole images. The reduced compression ratios required by the model can be traced to its one-zone nature. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Alameda Appl Sci Corp, San Leandro, CA 94577 USA. RP Mosher, D (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 36 TC 49 Z9 51 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 JUN PY 1998 VL 26 IS 3 BP 1052 EP 1061 DI 10.1109/27.700887 PG 10 WC Physics, Fluids & Plasmas SC Physics GA ZZ012 UT WOS:000074686400094 ER PT J AU Mittereder, JA Roussos, JA Christianson, KA Anderson, WT AF Mittereder, JA Roussos, JA Christianson, KA Anderson, WT TI Reliability life-testing and failure-analysis of GaAs monolithic Ku-band driver amplifiers SO IEEE TRANSACTIONS ON RELIABILITY LA English DT Article DE Arrhenius plot; gold-tin; field-effect transistor; gallium arsenide; infrared; Ku-band driver amplifier; lognormal distribution; monolithic microwave integrated circuit; radio frequency; silicon nitride; baseplate temperature; channel temperature ID HETEROJUNCTION BIPOLAR-TRANSISTORS AB Gallium-arsenide monolithic microwave integrated-circuit (MMIC) Ku-band driver amplifiers were life tested under accelerated high temperature, DC, and RF, conditions until failure. These MMIC are used in various applications such as radar and satellite communication systems. The failure mechanisms controlling their reliability must be understood in order to improve the lifetime for these and other applications. This paper discusses the experimental procedures, statistical evaluation of the data, and failure analysis of the devices. To our knowledge this is the first report of RF life testing of dual-gate driver amplifiers. The majority of the devices failed catastrophically due to high drain current, while others failed parametrically due to low output power. Failure analysis indicates that degradation of the Si3N4 dielectric layer to be the main failure mechanism in these MMIC. Statistical analysis revealed an activation energy of 0.87 eV and a median lifetime of 5.8.10(4) hours at 140 degrees C channel temperature, which is consistent with surface-phenomena failure mechanisms. C1 USN, Res Lab, Washington, DC 20375 USA. RP Mittereder, JA (reprint author), USN, Res Lab, Code 6855,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 15 TC 2 Z9 2 U1 2 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9529 J9 IEEE T RELIAB JI IEEE Trans. Reliab. PD JUN PY 1998 VL 47 IS 2 BP 119 EP 125 DI 10.1109/24.722272 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 128YJ UT WOS:000076435700006 ER PT J AU MacInnes, CS AF MacInnes, CS TI DOA estimation of nonstationary coherent signals using signal vector randomization SO IEEE TRANSACTIONS ON SIGNAL PROCESSING LA English DT Letter ID INTERFERENCE; SUBSPACE AB A method is presented for solving DOA tracking problems when there are correlated signals present. The new technique, which is called signal vector randomization, ran be used to efficiently eliminate an, correlation in the signals. This allows fast tracking methods to be used without any modification. The method is shown to be as effective as the spatial smoothing method. C1 USN, Underwater Warfare Ctr, Newport, RI 02841 USA. RP MacInnes, CS (reprint author), USN, Underwater Warfare Ctr, Newport, RI 02841 USA. NR 14 TC 0 Z9 0 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1053-587X J9 IEEE T SIGNAL PROCES JI IEEE Trans. Signal Process. PD JUN PY 1998 VL 46 IS 6 BP 1744 EP 1749 DI 10.1109/78.678514 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA ZP603 UT WOS:000073770000032 ER PT J AU Harris, DC AF Harris, DC TI Durable 3-5 mu m transmitting infrared window materials SO INFRARED PHYSICS & TECHNOLOGY LA English DT Article DE infrared; ultraviolet; visible; MgF2 ID REFRACTIVE-INDEX; HIGH-TEMPERATURE; ZINC-SULFIDE; SAPPHIRE; RESISTANCE; EROSION; DEPENDENCE; CERAMICS; SILICON; SURFACE AB Properties of 3-5 mu m infrared-transmitting window materials are reviewed, with an emphasis on durable materials for applications in environments involving moisture, impact by solid and liquid particles, high temperatures and rapid heating rates. Infrared, visible and ultraviolet transmission windows are compared for MgF2, aluminum oxynitride, sapphire, spinel, MgO, Y2O3, calcium aluminate, SiO2, CaF2, LiF, ZnS, ZnSe, GaAs, GaP, Si and Ge. Emission at elevated temperature, reflection and optical scatter are also discussed. A comparison of mechanical and thermal properties is given, as is a brief discussion of rain and particle erosion resistance. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Air Warfare Ctr, Div Weapons, Chem & Mat Branch,Res & Technol Div, China Lake, CA 93555 USA. RP Harris, DC (reprint author), USN, Air Warfare Ctr, Div Weapons, Chem & Mat Branch,Res & Technol Div, China Lake, CA 93555 USA. NR 80 TC 123 Z9 134 U1 9 U2 51 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1350-4495 J9 INFRARED PHYS TECHN JI Infrared Phys. Technol. PD JUN PY 1998 VL 39 IS 4 BP 185 EP 201 DI 10.1016/S1350-4495(98)00006-1 PG 17 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA ZZ616 UT WOS:000074748000002 ER PT J AU Yu, X Abe, R Hodes, RJ AF Yu, X Abe, R Hodes, RJ TI The role of B7-CD28 co-stimulation in tumor rejection SO INTERNATIONAL IMMUNOLOGY LA English DT Article DE B7-1; B7-2; CD80; CD86; EL4 ID B7-2 COSTIMULATORY MOLECULES; T-CELLS; ANTITUMOR IMMUNITY; INDUCTION; EXPRESSION; CTLA-4; CD80; CD28; ACTIVATION; RESPONSES AB The role of B7 co-stimulatory signaling in in vivo tumor rejection remains incompletely characterized. In particular, the relative competence of B7-1 (CD80) and B7-2 (CD86) to provide effective co-stimulus is not well defined, and the identification of the T cell co-stimulatory receptor that mediates B7 co-stimulation in tumor rejection has not been addressed. These issues were studied by assessing rejection of B7-negative or B7-transfected tumor cells in CD28-expressing or CD28-deficient hosts. B7-negative EL4 tumor cells grew progressively in normal syngeneic C57BL/6 (B6) mice. In contrast EL4 cells transfected with either full length B7-1 or full length B7-2 were rejected, indicating that both B7-1 and B7-2 are competent to mediate rejection of EL4 tumor cells. Expression of truncated B7-1 or B7-2 products, with complete deletion of cytoplasmic domains, was as effective as expression of full length B7-1 or B7-2 in mediating rejection. In contrast to the rejection of B7-transfected EL4 cells observed in CD28-expressing syngeneic hosts, B7-1- and B7-2-positive EL4 cells as well as control EL4 cells grew progressively in CDP8-deficient mice, demonstrating the requirement for host expression of CD28 in B7-mediated tumor rejection. These results indicate that interaction of host CD28 with co-stimulatory extracellular B7-1 or B7-2 ligands expressed on tumor cells can play a necessary role in mediating tumor rejection. C1 NCI, Expt Immunol Branch, NIH, Bethesda, MD 20892 USA. NIA, NIH, Bethesda, MD 20892 USA. USN, Med Res Inst, Immune Cell Biol Program, Bethesda, MD 20889 USA. RP Yu, X (reprint author), NCI, Expt Immunol Branch, NIH, Bldg 10,Room 4B10, Bethesda, MD 20892 USA. NR 32 TC 25 Z9 28 U1 1 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0953-8178 J9 INT IMMUNOL JI Int. Immunol. PD JUN PY 1998 VL 10 IS 6 BP 791 EP 797 DI 10.1093/intimm/10.6.791 PG 7 WC Immunology SC Immunology GA ZW523 UT WOS:000074419500010 PM 9678760 ER PT J AU Brook, I Frazier, EH AF Brook, I Frazier, EH TI Aerobic and anaerobic microbiology of chronic venous ulcers SO INTERNATIONAL JOURNAL OF DERMATOLOGY LA English DT Article ID LEG ULCERS; BACTERIAL-GROWTH; ABSCESSES; INFECTION; CHILDREN; FLORA; COCCI AB Background The role of bacteria in the pathogenesis of chronic venous leg ulcers (CVLU) is unclear. The objective of the study was to establish the aerobic and anaerobic bacteriology of CVLU. Methods A retrospective review was carried out of the clinical and microbiological laboratory records obtained from patients with CVLU. Microorganisms were grown from 43 specimens obtained from 41 patients. Results Aerobic or facultative bacteria alone were present in 18 (42%) specimens, anaerobic bacteria only in three (7%), and mixed aerobic-anaerobic flora in 22 (51%), In total, there were 97 isolates, 64 aerobic or facultative and 33 anaerobic, an average of 2.3 isolates per specimen (1.5 aerobes and 0.8 anaerobes), The predominant aerobic organisms were Staphylococcus aureus (26 isolates), group D streptococci (5), and Escherichia coli (5). The predominant anaerobes were Peptostreptococcus spp. (15), Bacteroides fragilis group (6), Propionibacterium acnes (4), and Prevotella spp. (3), Conclusions CVLU have a polymicrobial aerobic-anaerobic flora. C1 USN Hosp, Dept Pediat, Bethesda, MD 20814 USA. USN Hosp, Dept Infect Dis, Bethesda, MD 20814 USA. RP Brook, I (reprint author), POB 70412, Chevy Chase, MD 20813 USA. NR 22 TC 38 Z9 39 U1 0 U2 3 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0011-9059 J9 INT J DERMATOL JI Int. J. Dermatol. PD JUN PY 1998 VL 37 IS 6 BP 426 EP 428 DI 10.1046/j.1365-4362.1998.00445.x PG 3 WC Dermatology SC Dermatology GA ZZ193 UT WOS:000074704900006 PM 9646126 ER PT J AU Hubona, GS Everett, S Marsh, E Wauchope, K AF Hubona, GS Everett, S Marsh, E Wauchope, K TI Mental representations of spatial language SO INTERNATIONAL JOURNAL OF HUMAN-COMPUTER STUDIES LA English DT Article ID GRAPHICS-BASED DSS; PREFERENCE REVERSALS; REFERENCE POINTS; COGNITIVE MAPS; EXPERT SYSTEMS; MEMORY; KNOWLEDGE; CHOICE; ENVIRONMENTS; HIERARCHIES AB Previous studies have provided evidence of multi-level mental representations of language-conveyed spatial (scenic) information. However, the available evidence is largely inconclusive with regard to the structure of these mental representations. A laboratory experiment assesses computer-assisted problem-solving performance abilities when language-conveyed representations of spatial information are matched with the language perspective of the task and with individual cognitive sk.ills. Our findings largely validate this paradigm of "cognitive fit" that has been applied in non-language computer display domains, and the results suggest language-fostered "perspective-bias" in the formation and use of mental representations of spatial (scenic) information. (C) 1998 Acadamic Press. C1 Virginia Commonwealth Univ, Dept Informat Syst, Richmond, VA 23284 USA. USN, Res Lab, Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. RP Hubona, GS (reprint author), Virginia Commonwealth Univ, Dept Informat Syst, Box 844000, Richmond, VA 23284 USA. EM gshubona@atlas.vcu.edu; severett@aic.nrl.navy.mil; marsh@aic.nrl.navy.mil; wanchope@aic.nrl.navy.mil NR 62 TC 9 Z9 9 U1 1 U2 2 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 1071-5819 J9 INT J HUM-COMPUT ST JI Int. J. Hum.-Comput. Stud. PD JUN PY 1998 VL 48 IS 6 BP 705 EP 728 DI 10.1006/ijhc.1998.0188 PG 24 WC Computer Science, Cybernetics; Ergonomics; Psychology, Multidisciplinary SC Computer Science; Engineering; Psychology GA 101LC UT WOS:000074869600001 ER PT J AU Banker, AS De Clercq, E Taskintuna, I Keefe, KS Bergeron-Lynn, G Freeman, WR AF Banker, AS De Clercq, E Taskintuna, I Keefe, KS Bergeron-Lynn, G Freeman, WR TI Influence of intravitreal injections of HPMPC and related nucleoside analogues on intraocular pressure in guinea pig eyes SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Article; Proceedings Paper CT 67th Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY APR 21-26, 1996 CL FT LAUDERDALE, FLORIDA SP Assoc Res Vis & Ophthalmol ID IMMUNE-DEFICIENCY-SYNDROME; LONG-ACTING THERAPY; ANTI-DNA VIRUS; CYTOMEGALOVIRUS RETINITIS; MAINTENANCE TREATMENT; ANTIVIRAL COMPOUNDS; ORAL GANCICLOVIR; VIRAL RETINITIS; CIDOFOVIR; AIDS AB PURPOSE. Cidofovir (HPMPC) is a potent long-acting anticytomegalovirus agent. In humans, its dose-limiting intravitreal toxicity results in the lowering of intraocular pressure (IOP). The purpose of the present study was to determine the effects of HPMPC and various acyclic nucleoside phosphonate (ANP) analogues when administered intravitreally in guinea pig eyes and to establish the structural and functional relation of these compounds in connection with their effects on the ciliary body and retina. METHODS. Ninety-six guinea pig eyes were injected with various doses of HPMPC and ANP analogues. RESULTS. Severe lowering of IOP with structural alterations of the ciliary body was observed when doses were administered that achieved final intravitreal concentrations greater than 25 mu g/ml HPMPC, 200 mu g/ml cyclic HPMPC (cHPMPC), 25 mu g/ml (S)-HPMPA, and 625 mu g/ml PMEG. Concentrations of 25 mu g/ml HPMPC, 200 mu g/ml cHPMPC or less, and all concentrations of (R)-HPMPA, HPMPU, PMEA, PMEC, PMEDAP, (R)-PMPA, and (S)-PMPA did not lower IOP significantly, nor did they cause significant histologic changes. CONCLUSIONS. Of the HPMP series, the cyclic analogue of HPMPC (cHPMPC) and HPMPC are the least toxic of the compounds that show potent anti-human cytomegalovirus activity (HCMV). PMEG, the most potent anti-HCMV compound of the PME series, is toxic at higher doses. Further evaluation of lower doses is needed. Compounds of the PMP series are not toxic, but they show no anti-HCMV activities. The IOP-lowering effect of these compounds appears to be associated with an effect on the ciliary body. C1 Univ Calif San Diego, Shiley Eye Ctr, Dept Ophthalmol, La Jolla, CA 92093 USA. Katholieke Univ Leuven, Rega Inst Med Res, B-3001 Louvain, Belgium. USN Hosp, Dept Ophthalmol & Clin Invest, San Diego, CA 92134 USA. RP Freeman, WR (reprint author), Univ Calif San Diego, Shiley Eye Ctr, Dept Ophthalmol, 9415 Campus Point Dr, La Jolla, CA 92093 USA. FU NEI NIH HHS [EY07366] NR 30 TC 7 Z9 7 U1 0 U2 3 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD JUN PY 1998 VL 39 IS 7 BP 1233 EP 1242 PG 10 WC Ophthalmology SC Ophthalmology GA ZQ631 UT WOS:000073887400020 PM 9620084 ER PT J AU Dick, SJ AF Dick, SJ TI To see the unseen: A history of planetary radar astronomy. SO ISIS LA English DT Book Review C1 USN Observ, Washington, DC 20392 USA. RP Dick, SJ (reprint author), USN Observ, Washington, DC 20392 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 0021-1753 J9 ISIS JI Isis PD JUN PY 1998 VL 89 IS 2 BP 364 EP 365 DI 10.1086/384056 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA ZX051 UT WOS:000074475300060 ER PT J AU Roldan, JM Cressler, JD Niu, G Clark, SD Nguyen-Ngoc, D AF Roldan, JM Cressler, JD Niu, G Clark, SD Nguyen-Ngoc, D TI Gamma radiation tolerance of UHV/CVD SiGe BiCMOS technology operated at cryogenic temperatures SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 3rd European Workshop on Low Temperature Electronics (WOLTE 3) CY JUN 24-26, 1998 CL SAN MINIATO, ITALY ID TOTAL-DOSE RESPONSE; TRANSISTORS AB This paper presents for the first time the effects of ionizing gamma rays on a high-performance UHV/CVD SiGe BiCMOS technology irradiated at both 300K and 77K. The SiGe HBTs show a degradation in current gain below 10% at 300K and no observable shifts in current gain at 77K. The Si pFETs are radiation hard to 1.0 Mrad(Si) at both 300K and 77K, while the Si nFETs are able to withstand 100 krad(Si). In this work, we examine the total dose response of SiGe HBTs and concentrate on the post-radiation behavior of the nFETs and pFETs irradiated under bias at both 300K and 77K. C1 Auburn Univ, Alabama Microelect Sci & Technol Ctr, Dept Elect Engn, Auburn, AL 36849 USA. USN, Ctr Surface Warfare, Crane, IN 47522 USA. IBM Microelect, Hopewell Junction, NY 12533 USA. RP Roldan, JM (reprint author), Auburn Univ, Alabama Microelect Sci & Technol Ctr, Dept Elect Engn, 200 Broun Hall, Auburn, AL 36849 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD JUN PY 1998 VL 8 IS P3 BP 99 EP 102 DI 10.1051/jp4:1998323 PG 4 WC Physics, Multidisciplinary SC Physics GA ZZ686 UT WOS:000074756500024 ER PT J AU Wilderson, PW AF Wilderson, PW TI Culture change and the new technology: An archaeology of the early American industrial era. SO JOURNAL OF AMERICAN HISTORY LA English DT Book Review C1 USN Inst, Annapolis, MD USA. RP Wilderson, PW (reprint author), USN Inst, Annapolis, MD USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION AMER HISTORIANS PI BLOOMINGTON PA 112 N BRYAN ST, BLOOMINGTON, IN 47408 USA SN 0021-8723 J9 J AM HIST JI J. Am. Hist. PD JUN PY 1998 VL 85 IS 1 BP 237 EP 237 DI 10.2307/2568491 PG 1 WC History SC History GA 109MP UT WOS:000075326600059 ER PT J AU Freeland, JW Chakarian, V Bussmann, K Idzerda, YU Wende, H Kao, CC AF Freeland, JW Chakarian, V Bussmann, K Idzerda, YU Wende, H Kao, CC TI Exploring magnetic roughness in CoFe thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID X-RAY; CIRCULAR-DICHROISM; SCATTERING; SUPERLATTICES; MULTILAYERS; EDGES AB The behavior of chemical and magnetic interfaces is explored using diffuse x-ray resonant magnetic scattering (XRMS) for CoFe thin films with varying interfacial roughnesses. A comparison of the chemical versus magnetic interfaces shows distinct differences in the behavior of these two related interfaces as the chemical roughness is increased. Such changes appear to be correlated with the behavior of the magnetic hysteresis of the interface, measured by tracking the diffuse XRMS intensity as a function of applied magnetic field. (C) 1998 American Institute of Physics. [S0021-8979(98)17511-4]. C1 USN, Res Lab, Washington, DC 20375 USA. Free Univ Berlin, D-14195 Berlin, Germany. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Freeland, JW (reprint author), Naval Res Lab, NSLS Bldg 725A-U4B, Upton, NY 11973 USA. RI Wende, Heiko/J-8505-2012 NR 19 TC 47 Z9 48 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 JUN 1 PY 1998 VL 83 IS 11 BP 6290 EP 6292 DI 10.1063/1.367544 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500024 ER PT J AU Tonnerre, JM Seve, L Barbara-Dechelette, A Bartolome, F Raoux, D Chakarian, V Kao, CC Fischer, H Andrieu, S Fruchart, O AF Tonnerre, JM Seve, L Barbara-Dechelette, A Bartolome, F Raoux, D Chakarian, V Kao, CC Fischer, H Andrieu, S Fruchart, O TI Soft x-ray resonant magnetic reflectivity study of thin films and multilayers SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID EXCHANGE SCATTERING; CIRCULAR-DICHROISM; IRON; EDGES; BCC AB Soft x-ray resonant magnetic reflectivity measurements on thin films and multilayers in a transverse geometry using linear polarized photons are presented. Magneto-optic calculations taking into account the layer roughness allows us to reproduce all the experimental features of the angular and energy reflectivity curves as well as the asymmetry ratio in both cases. Application to FexMn1-x alloy films epitaxially grown on Ir(001) brings more insights on the magnetic transition occurring at x=0.75. (C) 1998 American Institute of Physics. [S0021-8979(98)49911-0]. C1 Univ Grenoble 1, CNRS, Lab Cristallog, F-38042 Grenoble 9, France. USN, Res Lab, Washington, DC 20375 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Univ Nancy, CNRS, LPM, F-54506 Vandoeuvre Nancy, France. Univ Grenoble 1, CNRS, Lab Louis Neel, F-38042 Grenoble 9, France. RP Tonnerre, JM (reprint author), Univ Grenoble 1, CNRS, Lab Cristallog, BP 166, F-38042 Grenoble 9, France. RI Bartolome, Fernando/K-1700-2014; andrieu, stephane/N-3654-2016; OI Bartolome, Fernando/0000-0002-0047-1772; andrieu, stephane/0000-0003-0373-8193; Fruchart, Olivier/0000-0001-7717-5229 NR 21 TC 26 Z9 26 U1 0 U2 1 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 1 PY 1998 VL 83 IS 11 BP 6293 EP 6295 DI 10.1063/1.367837 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500025 ER PT J AU Koller, D Osofsky, MS Chrisey, DB Horwitz, JS Soulen, RJ Stroud, RM Eddy, CR Kim, J Auyeung, RCY Byers, JM Woodfield, BF Daly, GM Clinton, TW Johnson, M AF Koller, D Osofsky, MS Chrisey, DB Horwitz, JS Soulen, RJ Stroud, RM Eddy, CR Kim, J Auyeung, RCY Byers, JM Woodfield, BF Daly, GM Clinton, TW Johnson, M TI Suppression of superconductivity by injection of spin-polarized current SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID FILMS AB A spin polarized current has been injected into high T-c superconductors resulting in a significant reduction in the superconductor's critical current. Such injection may serve as the basis of a new class of superconducting devices for control, switching and amplification. Preliminary results using both Permalloy and CMR materials as injectors an presented. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Washington, DC 20375 USA. RP Koller, D (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Stroud, Rhonda/C-5503-2008; Osofsky, Michael/A-1050-2010 OI Stroud, Rhonda/0000-0001-5242-8015; NR 8 TC 30 Z9 30 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 1 PY 1998 VL 83 IS 11 BP 6774 EP 6776 DI 10.1063/1.367763 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500184 ER PT J AU Clinton, TW Johnson, M AF Clinton, TW Johnson, M TI Magnetoquenched superconducting valve SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID INJECTION; FERROMAGNET AB A superconducting switch has been developed in a simple bilayer cross strip geometry using the magnetic fringe field of a ferromagnetic film to control the critical current in an underlying superconducting bridge. The magnetization of the ferromagnet is rotated in the plane of the film to vary the magnitude of the fringe field locally applied to the superconductor from negligible to substantial values. In the latter case, the magnetization is oriented such that the magnetic poles are along the edges of the cross strip directly above the superconductor. The large fringe field near the poles suppresses superconductivity over a length of order microns, giving rise to superconducting weak link behavior. A large modulation of the critical current is observed. The effect is demonstrated in the low T-c superconductors Pb (T-c = 7.3 K) and Sn (T-c = 3.9 K). Fabrication of the device involves minimal processing. Applications as a high speed switch, amplifier, nonvolatile storage cell, and controllable weak link are possible. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Washington, DC 20375 USA. RP Clinton, TW (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 12 TC 8 Z9 8 U1 0 U2 1 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 1 PY 1998 VL 83 IS 11 BP 6777 EP 6779 DI 10.1063/1.367528 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500185 ER PT J AU Dong, ZW Pai, SP Ramesh, R Venkatesan, T Johnson, M Chen, ZY Cavanaugh, A Zhao, YG Jiang, XL Sharma, RP Ogale, S Greene, RL AF Dong, ZW Pai, SP Ramesh, R Venkatesan, T Johnson, M Chen, ZY Cavanaugh, A Zhao, YG Jiang, XL Sharma, RP Ogale, S Greene, RL TI Novel high-T-c transistors with manganite oxides SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID TUNNEL INJECTION; QUASI-PARTICLES; SUPERCONDUCTOR; DEVICES; FILMS; HETEROSTRUCTURES; FERROMAGNET; SUPPRESSION AB One viable approach for transistor-like high-T-c three terminal devices is the quasiparticle injection device (QPID). We have fabricated Au/YBa2Cu3O7/LaAlO3 /Nd0.7Sr0.3MnO3 (NSMO) and Au/YBa2Cu3O7/LaAlO3/LaNiO3 (LNO) heterostructures on (100) LaAlO3 substrates by pulsed laser deposition for studies of quasiparticle injection effects in high-T-c superconducting thin films, The effect of the injection of spin-polarized quasiparticles from a ferromagnetic NSMO gate was compared to that of unpolarized quasiparticles from a nonmagnetic metallic LNO gate. A current gain greater than nine has been attained for spin-polarized QPIDs, which is an order of magnitude larger than the gain of spin unpolarized QPIDs. Such large effects could be useful in a variety of active high-T-c/colossal magnetoresistance heterostructure devices. (C) 1998 American Institute of Physics. C1 Univ Maryland, Dept Phys, NSF, MRSEC Oxides, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Maryland, Ctr Supercond Res, College Pk, MD 20742 USA. RP Dong, ZW (reprint author), Read Rite Corp, 44100 Osgood Rd, Fremont, CA 94539 USA. RI Venkatesan, Thirumalai/E-1667-2013 NR 24 TC 23 Z9 23 U1 1 U2 5 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 1 PY 1998 VL 83 IS 11 BP 6780 EP 6782 DI 10.1063/1.367764 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500186 ER PT J AU Harris, VG Fatemi, DJ Browning, VM Osofsky, MS Vanderah, TA AF Harris, VG Fatemi, DJ Browning, VM Osofsky, MS Vanderah, TA TI Extended x-ray absorption fine structure measurements of nonsuperconducting PrBa2Cu3O6.9: Evidence against Ba site Pr substitution SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID ELECTRONIC-STRUCTURE; SUPERCONDUCTIVITY; HYBRIDIZATION; TEMPERATURE; SUPPRESSION; SCATTERING; ORDER AB Extended x-ray absorption fine structure (EXAFS) measurements on nonsuperconducting PrBa2Cu3O6.9 are reported. Theoretical Pr L-II EXAFS data, calculated for the case of Y-site and Ba-site occupation, were least-squares fit to the experimental Pr L-II EXAFS. Results indicate that the Pr ions overwhelmingly occupy the Y sites. These results present a serious challenge to models which rely on Ba-site Pr substitution as an explanation for the lack of superconductivity in PrBa2Cu3O6.9. C1 USN, Res Lab, Washington, DC 20375 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Harris, VG (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Harris, Vincent/A-8337-2009; Osofsky, Michael/A-1050-2010 NR 20 TC 8 Z9 8 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1998 VL 83 IS 11 BP 6783 EP 6785 DI 10.1063/1.367709 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500187 ER PT J AU Lubitz, P Krebs, JJ Miller, MM Cheng, SF AF Lubitz, P Krebs, JJ Miller, MM Cheng, SF TI Temperature dependence of ferromagnetic resonance as induced by NiO pinning layers SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID EXCHANGE-ANISOTROPY; CO AB Ferromagnetic resonance (FMR) experiments have been conducted near 9.5 GHz on permalloy (Py) thin films which are components of spin valves and related structures. These so-called giant magnetoresistance structures often use antiferromagnetic NiO to achieve pinning of one magnetic layer. Magnetic anisotropies acting on these pinned layers were deduced by observing their resonances for fields perpendicular to and in the sample plane. We used data taken from 4 to 600 K to identify potential mechanisms of pinning, anisotropy, and linewidth. The anisotropic exchange pinning and an isotropic downward FMR shift vanish at a blocking temperature well below the bulk Neel temperature of NiO. The strong temperature dependencies of the isotropic shift and linewidth may reflect the presence of different spin pinning subsystems and the different time scales of the FMR and low frequency or static measurements. C1 USN, Res Lab, Washington, DC 20375 USA. RP Lubitz, P (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 10 TC 30 Z9 31 U1 1 U2 5 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 1 PY 1998 VL 83 IS 11 BP 6819 EP 6821 DI 10.1063/1.367662 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500199 ER PT J AU Fatemi, DJ Harris, VG Browning, VM Kirkland, JP AF Fatemi, DJ Harris, VG Browning, VM Kirkland, JP TI Processing and cation redistribution of MnZn ferrites via high-energy ball milling SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID ABSORPTION FINE-STRUCTURE; MAGNETIC-PROPERTIES; ZINC FERRITE; MNFE2O4 AB We have produced MnZn ferrites via high-energy ball milling (HEBM) of elemental oxides MnO, ZnO, and Fe2O3. X-ray diffraction (XRD) indicates a pure phase spinel forms after 21 h of HEBM. Extended x-ray absorption fine structure (EXAFS) analysis shows a nonequilibrium cation distribution, with an unusually high population of Zn cations on the octahedral sublattice. We then used EXAFS modeling to study cation site occupancy in an equilibrium MnZn-ferrite standard subjected to HEBM. We found that HEBM produces an increased preference for octahedral-site occupation among all cations for milling durations up to 300 min. After an initial improvement in magnetic properties, the magnetization diminishes steadily throughout this interval. With further increases in milling duration these structural and magnetic trends reverse, possibly due to annealing effects evidenced by XRD. (C) 1998 American Institute of Physics. [S0021-8979(98)42311-9]. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Landover, MD 20785 USA. RP Fatemi, DJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Harris, Vincent/A-8337-2009 NR 13 TC 85 Z9 87 U1 1 U2 17 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 1 PY 1998 VL 83 IS 11 BP 6867 EP 6869 DI 10.1063/1.367766 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500215 ER PT J AU Harris, VG Fatemi, DJ Suresh, KG Rao, KVSR AF Harris, VG Fatemi, DJ Suresh, KG Rao, KVSR TI Effect of Al substitution on the local environments and magnetic properties of partially nitrogenated (Er0.5Pr0.5)(2)Fe-17 permanent magnets SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID ND2FE17-XALX SOLID-SOLUTIONS; NEUTRON-DIFFRACTION; MOSSBAUER AB Extended x-ray absorption fine structure measurements of the Fe K, and Pr and Er L-111 absorption edges, were carried out to elucidate the relationship between the local structure and magnetism in Al substituted, partially nitrogenated (Er0.5Pr0.5)(2)Fe-17 permanent magnets. We find that the nitrogenation acts to dilate both the Fe-Fe and the (Pr,Er)-Fe bonds, thus raising the T-C via a magnetovolume effect. However, nitrogenation of Al-substituted samples acts to decrease the average Fe-Fe bond distance, thus reducing the exchange on the Fe sublattice and lowering T-C relative to the nitrogenated parent compound. This is opposite to the trend measured in systems when N is absent. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Washington, DC 20375 USA. Indian Inst Technol, Dept Phys, Madras 600036, Tamil Nadu, India. RP Harris, VG (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Harris, Vincent/A-8337-2009 NR 16 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1998 VL 83 IS 11 BP 6920 EP 6922 DI 10.1063/1.367711 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500231 ER PT J AU Wende, H Freeland, JW Chakarian, V Idzerda, YU Lemke, L Baberschke, K AF Wende, H Freeland, JW Chakarian, V Idzerda, YU Lemke, L Baberschke, K TI Probing local magnetic disorder by investigating spin dependent photoelectron scattering SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID RAY-ABSORPTION SPECTRA; CIRCULAR-DICHROISM; IRON; EDGE AB We present here systematic temperature dependent magnetic extended x-ray absorption spectroscopy (MEXAFS) measurements. This fine structure can be explained by the spin dependent scattering of the photoelectron and yields information about the local magnetic surroundings of the absorbing atom. We find a strong temperature dependence at temperatures far below the Curie temperature. This shows that the intensity of the MEXAFS signal is not only determined by the value of the magnetic moment but also by the relative vibrations of the backscattering atom to the absorbing atom. (C) 1998 American Institute of Physics. [S0021-8979(98)50311-8]. C1 USN, Res Lab, Washington, DC 20375 USA. Free Univ Berlin, Inst Phys Expt, D-14195 Berlin, Germany. RP Wende, H (reprint author), USN, Res Lab, Code 6345, Washington, DC 20375 USA. RI Wende, Heiko/J-8505-2012 NR 17 TC 13 Z9 14 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1998 VL 83 IS 11 BP 7028 EP 7030 DI 10.1063/1.367841 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500268 ER PT J AU Wang, D Daughton, JM Bussmann, K Prinz, GA AF Wang, D Daughton, JM Bussmann, K Prinz, GA TI Magnetic properties of very thin single and multilayer NiFeCo and CoFe films deposited by sputtering SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID FIELD AB As the size of the giant magneto resistive (GMR) devices continues to decrease into submicrometer regime, the demagnetizing field from the magnetic layers will increase to very high values, prohibiting switching with a reasonably small current. The most feasible way to reduce it is to make the magnetic layers thinner. Single layers of NiFeCo and CoFe films as well as multilayers consisting of these with various underlayers have been deposited by rf diode sputtering in a magnetic field. NiFeCo becomes nonmagnetic at 15, 10, and 6 Angstrom when using Ta, Si3N4, and Cu underlayers, respectively. The magnetization of NiFeCo films sandwiched with Cu decreases as the films become thinner, indicating that about one atomic layer loses its magnetic moment at each interface with Cu. The induced magnetic anisotropy is a strong function of the NiFeCo film thickness, changing from 7 Oe for 20 Angstrom to 17 Oe for 100 Angstrom. CoFe films lose very little magnetic moment at the interfaces with Cu. Multilayers of [NiFeCo/Cu/CoFe/Cu] with different Cu underlayer thickness have been made and the magnetic and GMR properties show a strong dependence on the Cu buffer layer thickness due to different interface roughnesses. With proper designing of the interfaces, these very thin magnetic films have high potential for ultrahigh-density magnetic memory and other applications. (C) 1998 American Institute of Physics. [S0021-8979(98)37711-7]. C1 Nonvolatile Elect Inc, Eden Prairie, MN 55344 USA. USN, Res Lab, Washington, DC 20375 USA. RP Wang, D (reprint author), Nonvolatile Elect Inc, 11409 Valley View Rd, Eden Prairie, MN 55344 USA. NR 5 TC 19 Z9 20 U1 0 U2 10 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 1 PY 1998 VL 83 IS 11 BP 7034 EP 7036 DI 10.1063/1.367724 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500270 ER PT J AU Rubinstein, M Broussard, PR Allen, LH Hathaway, KB Miller, MM Sun, JZ AF Rubinstein, M Broussard, PR Allen, LH Hathaway, KB Miller, MM Sun, JZ TI Investigation of granular films composed of interdispersed La1/3Ca2/3MnO3 particles and metallic Au particles SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc AB We have carried out a study of composite, granular films made by depositing LCMO (a colossal magnetoresistive perovskite) and pure, metallic Au onto MgO and LaAlO3 substrates. Elevated temperature caused the Au to segregate into small, micron-sized granules. The films were studied by atomic force microscopy, magnetoresistivity, superconducting quantum interference device magnetization measurements, and magnetically modulated microwave absorption. (C) 1998 American Institute of Physics. [S0021-8979(98)28011-X]. C1 USN, Res Lab, Washington, DC 20375 USA. IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. RP Rubinstein, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM rubinstein@anvil.nrl.navy.mil RI Sun, Jonathan/C-2773-2009 NR 9 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1998 VL 83 IS 11 BP 7067 EP 7069 DI 10.1063/1.367641 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500281 ER PT J AU Browning, VM Stroud, RM Fuller-Mora, WW Byers, JM Osofsky, MS Knies, DL Grabowski, KS Koller, D Kim, J Chrisey, DB Horwitz, JS AF Browning, VM Stroud, RM Fuller-Mora, WW Byers, JM Osofsky, MS Knies, DL Grabowski, KS Koller, D Kim, J Chrisey, DB Horwitz, JS TI Magnetic and transport properties of radiation damaged La0.7Ca0.3MnO3.0 thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID MAGNETORESISTANCE; LA0.67CA0.33MNO3; RESISTIVITY AB Magnetization and resistivity measurements are reported fur a series of radiation damaged La0.7Ca0.3MnO3 pulsed laser deposited thin films. When plotted as a function of activation energy, trends in the electrical transport properties are similar to those exhibited in the magnetic properties. A sharp drop in both T-c and T-p in samples with activation energies greater than similar to 110 meV suggests a "decoupling" of the magnetic and transport properties. The results suggest the magnetic order is no longer sufficient to delocalize the system of the extra disorder induced by the radiation damage. [S0021-8979(98)38011-1]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Browning, VM (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Stroud, Rhonda/C-5503-2008; Osofsky, Michael/A-1050-2010; OI Stroud, Rhonda/0000-0001-5242-8015; Grabowski, Kenneth/0000-0003-0816-001X NR 10 TC 22 Z9 22 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 1 PY 1998 VL 83 IS 11 BP 7070 EP 7072 DI 10.1063/1.367727 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500282 ER PT J AU Stroud, RM Kim, J Eddy, CR Chrisey, DB Horwitz, JS Koller, D Osofsky, MS Soulen, RJ Auyeung, RCY AF Stroud, RM Kim, J Eddy, CR Chrisey, DB Horwitz, JS Koller, D Osofsky, MS Soulen, RJ Auyeung, RCY TI Fabrication of YBa2Cu3O7-delta/SrTiO3/La0.7Sr0.3MnO3-delta junctions for the control of supercurrent by spin-polarized quasiparticle current injection SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc AB Supercurrent suppression by the injection of spin-polarized quasiparticle current from a ferromagnet into a superconductor is demonstrated in YBa2Cu3O7-delta/SrTiO3/La0.7Sr0.3MnO3-delta junctions at 77 K. Negative current gains as large as 35 have been observed. The magnitude of the effect depends on the net polarization of the injection current, film resistivities, barrier microstructure, and injection geometry. Fabrication of the junctions is discussed in terms of optimizing these parameters for maximum supercurrent suppression. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Largo, MD 20774 USA. RP Stroud, RM (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Stroud, Rhonda/C-5503-2008; Osofsky, Michael/A-1050-2010 OI Stroud, Rhonda/0000-0001-5242-8015; NR 7 TC 33 Z9 33 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1998 VL 83 IS 11 BP 7189 EP 7191 DI 10.1063/1.367676 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500322 ER PT J AU Wun-Fogle, M Restorff, JB Clark, AE Lindberg, JF AF Wun-Fogle, M Restorff, JB Clark, AE Lindberg, JF TI Magnetization and magnetostriction of dendritic [112] TbxDyyHozFe1.95 (x+y+z=1) rods under compressive stress SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc AB The field dependencies of the magnetization and magnetostriction of the Laves phase pseudobinary TbxDyyHozFe1.95 (x + y + z = 1) compounds were measured as a function of compressive stress T (10 MPa < \T\ < 70 MPa) and applied magnetic field H (0 < H< 135 kA/m). Values of x, y, and z were chosen to obtain minimum magnetic anisotropy and easy magnetization axis rotation near room temperature. At a compressive stress of 34 MPa, the addition of Ho to the binary Tb1-xDyxFe1.95 compound reduced the width of the strain versus magnetic field hysteresis curves in Tb0.28Dy0.57Ho0.15Fe1.95 and Tb0.26Dy0.54Ho0.2Fe1.95 by 23% and 54%, respectively, compared to the original alloy, while the strains were reduced by only 7% and 10%. (C) 1998 American Institute of Physics. [S0021-8979(98)34411-4]. C1 Naval Surface Warfare Ctr, Carderock Div, W Bethesda, MD 20817 USA. Clark Associates, Adelphi, MD 20783 USA. USN, Ctr Underwater Syst, Newport, RI 02841 USA. RP Wun-Fogle, M (reprint author), Naval Surface Warfare Ctr, Carderock Div, Code 684, W Bethesda, MD 20817 USA. EM wunfogle@oasys.dt.navy.mil NR 3 TC 27 Z9 27 U1 1 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 1 PY 1998 VL 83 IS 11 BP 7279 EP 7281 DI 10.1063/1.367700 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500352 ER PT J AU Lindgren, EA Haroush, S Poret, JC Mazzatesta, AD Rosen, M Wun-Fogle, M Restorff, JB Clark, AE Lindberg, JF AF Lindgren, EA Haroush, S Poret, JC Mazzatesta, AD Rosen, M Wun-Fogle, M Restorff, JB Clark, AE Lindberg, JF TI Development of Terfenol-D transducer material SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc AB Terfenol-D, Tb1-xDyxFe2 (x congruent to 0.7), is successfully used as a magnetostrictive transducer material for low-frequency applications. To extend the frequency range of magnetostrictive transducers into the high kHz and MHz range, new materials processing techniques must be developed to minimize eddy current losses. The method that has demonstrated the greatest potential to date is based on rapid solidification by melt spinning to obtain thin strips of material. The objective of this program includes refining the casting procedure to yield ribbons with the [111] direction oriented along the length of the ribbon, with the (110) plane in the plane of the ribbon. The crystallographic orientation of the Terfenol-D ribbons have been controlled by varying the cooling rate of the melt-spinning process. The cooling rates were controlled by a number of parameters in the melt-spinning process and ribbons have been obtained with an enhancement of the (110) plane parallel to the surface of the ribbon. Magnetostrictive measurements under tensile stresses up to 3 MPa and magnetic fields up to 4 kOe yielded magnetostrictive displacements of 850 x 10(-6). (C) 1998 American Institute of Physics. [S0021-8979(98)25711-2]. C1 Ind Qual Inc, Gaithersburg, MD 20879 USA. Johns Hopkins Univ, Dept Mat Sci & Engn, Baltimore, MD 21218 USA. Naval Surface Warfare Ctr, Carderock Div Code 684, Bethesda, MD 20917 USA. Clark Associates, Adelphi, MD 20783 USA. USN, Underwater Warfare Ctr Code 213, Newport, RI 02841 USA. RP Lindgren, EA (reprint author), Ind Qual Inc, Gaithersburg, MD 20879 USA. NR 5 TC 10 Z9 10 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 JUN 1 PY 1998 VL 83 IS 11 BP 7282 EP 7284 DI 10.1063/1.367618 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500353 ER PT J AU Restorff, JB Wun-Fogle, M Clark, AE AF Restorff, JB Wun-Fogle, M Clark, AE TI Piezomagnetic properties, saturation magnetostriction, and Delta E effect in DyZn at 77 K SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID CRYSTAL AB Young's modulus, magnetization, and magnetostriction measurements were made as a function of applied magnetic field (0 < H < 160 kA/m) and compressive stress (8.5 MPa < \T\ < 57.3 MPa) in [100] single crystal DyZn at 77 K. Piezomagnetic d constants greater than 300 nm/A and changes in Young's modulus greater than 40 GPa were found. Pronounced features are abrupt changes in the elastic moduli, magnetostriction, and coupling factors arising from "jumps" in the magnetization occurring as the moment changes from one easy [100] axis to another. The characteristic magnetic fields at which this change occurs depend strongly upon the stress induced magnetic anisotropy. Magnetomechanical coupling factors reach 0.91. (C) 1998 American Institute of Physics. [S0021-8979(98)34511-9]. C1 Naval Surface Warfare Ctr, Carderock Div, W Bethesda, MD 20817 USA. Clark Associates, Adelphi, MD 20783 USA. RP Restorff, JB (reprint author), Naval Surface Warfare Ctr, Carderock Div, Code 684, W Bethesda, MD 20817 USA. NR 6 TC 10 Z9 10 U1 1 U2 9 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 1 PY 1998 VL 83 IS 11 BP 7288 EP 7290 DI 10.1063/1.367701 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500355 ER PT J AU Singh, DJ Pickett, WE AF Singh, DJ Pickett, WE TI Lattice effects in ferromagnetic manganite perovskites SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID ELECTRONIC-STRUCTURE; LA1-XCAXMNO3 SYSTEM; PYROCHLORE TL2MN2O7; DOUBLE EXCHANGE; TRANSPORT; MAGNETORESISTANCE; CHARGE AB Density functional calculations are used to investigate the relationships among lattice distortions, magnetic ordering, and electronic properties in manganite perovskites. Distortions open narrow pseudogaps at the middle of the majority e(g) manifold. The effect on transport is very dependent on doping and falls off as divalent ions replace La in LaMnO3. Distortions in the ferromagnetic ordered colossal magnetoresistance regime are weakly coupled to electronic properties relative to pure LaMnO3. (C) 1998 American Institute of Physics. [S0021-8979(98)32111-8]. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Singh, DJ (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RI Singh, David/I-2416-2012 NR 22 TC 8 Z9 9 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1998 VL 83 IS 11 BP 7354 EP 7356 DI 10.1063/1.367678 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500376 ER PT J AU Kresin, VZ Wolf, SA AF Kresin, VZ Wolf, SA TI Isotope effect and T-c in manganites and high T-c oxides SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 7th Joint Magnetism and Magnetic Materials / International Magnetics Conference CY JAN 06-09, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Inst Phys, IEEE Magnet Soc, TMS, Off Naval Res, Amer Soc Testing & Mat, Amer Ceram Soc ID RESISTIVITY; TRANSPORT; SYSTEM; SHIFT; FILMS AB Oxygen isotope effect in manganites (cuprates) is caused by the dynamic Jahn-Teller effect on the bridging oxygen ion (e.g., the ion between Mn3+ and Mn4+ in manganites). This effect leads also to the vibronic reduction and effective decrease of the ferromagnetic transition temperature. (C) 1998 American Institute of Physics. [S0021-8979(98)32211-2]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. USN, Res Lab, Washington, DC 20375 USA. RP Kresin, VZ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Wolf, Stuart/A-7513-2009 NR 30 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1998 VL 83 IS 11 BP 7357 EP 7359 DI 10.1063/1.367679 PN 2 PG 3 WC Physics, Applied SC Physics GA 152UQ UT WOS:000077795500377 ER PT J AU May, DA Osterman, WO AF May, DA Osterman, WO TI Satellite-derived sea surface temperatures: Evaluation of GOES-8 and GOES-9 multispectral imager retrieval accuracy SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID DRIFTING BUOYS; VALIDATION; PREDICTION AB Sea surface temperature (SST) retrieval accuracy from the multispectral imager on the new generation of GOES satellites is analyzed. Equations for two and three infrared channels are empirically derived using cloud-free satellite radiances matched to buoy SST measurements obtained in 1995 and 1996. Both GOES-8 and GOES-9 demonstrate the capability to retrieve sea surface temperature at better than 1-K root-mean-square difference (rmsd) with negligible bias relative to buoy SST measurements. GOES-S rmsd errors are found to be 0.79 K (day) and 0.81 K (night). GOES-9 rmsd errors are 0.65 K (day) and 0.59 K (night). The GOES-9 results are relatively comparable to those: currently achieved operationally from the NOAA polar-orbiting satellite Advanced Very High Resolution Radiometer sensor. Investigation revealed that GOES imager multiple detector scan striping impacted SST accuracy requiring sample array averaging for best results. C1 USN, Res Lab, Remote Sensing Applicat Branch, Stennis Space Ctr, MS 39529 USA. RP May, DA (reprint author), USN, Res Lab, Remote Sensing Applicat Branch, NLR Code 7240, Stennis Space Ctr, MS 39529 USA. NR 30 TC 13 Z9 13 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD JUN PY 1998 VL 15 IS 3 BP 788 EP 797 DI 10.1175/1520-0426(1998)015<0788:SDSSTE>2.0.CO;2 PG 10 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA ZQ890 UT WOS:000073913300015 ER PT J AU Deschamps, JR George, C Flippen-Anderson, JL Demilo, AB Bordas, B AF Deschamps, JR George, C Flippen-Anderson, JL Demilo, AB Bordas, B TI X-ray crystallographic and molecular modeling studies of 1-(2,6-difluorobenzoyl)-5-(4-chlorophenyl)biuret SO JOURNAL OF CHEMICAL CRYSTALLOGRAPHY LA English DT Article AB Crystals of 1-(2,6-difluorobenzoyl)-5-(4-chlorophenyl)biuret (BFB), C(15)H(10)N(3)O(3)F(2)Cl, were grown by evaporation from an acetonitrile solution. Two polymorphs were obtained. The first polymorph (BFB1) crystallized in the monoclinic space group P2(1)/c (Z = 4) with unit cell a = 13.021(3), b = 5.293(1), c = 21.199(6) Angstrom, and beta = 97.34(2)degrees, The second polymorph (BFB2) crystallized in the orthorhombic space group beta 2(1)2(1)2(1) (Z = 8) with a = 10.513(1), b = 10.806(1), and c = 26.685(1) Angstrom. The results of crystallographic and molecular modeling studies on BFB were in good agreement. The compound has an extended conformation with the benzene rings coplanar and the intervening -CONHCONHCONH- moiety rotated out of the plane due to steric effects from the two fluorine atoms. C1 USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. ARS, USDA, Washington, DC 20250 USA. Hungarian Acad Sci, Inst Plant Protect, H-1525 Budapest, Hungary. RP Deschamps, JR (reprint author), USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RI G, Neela/H-3016-2014; OI Deschamps, Jeffrey/0000-0001-5845-0010 NR 12 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1074-1542 J9 J CHEM CRYSTALLOGR JI J. Chem. Crystallogr. PD JUN PY 1998 VL 28 IS 6 BP 453 EP 459 DI 10.1023/A:1021768622056 PG 7 WC Crystallography; Spectroscopy SC Crystallography; Spectroscopy GA 127ZQ UT WOS:000076381100005 ER PT J AU Minnotte, MC Marchette, DJ Wegman, EJ AF Minnotte, MC Marchette, DJ Wegman, EJ TI The bumpy road to the mode forest SO JOURNAL OF COMPUTATIONAL AND GRAPHICAL STATISTICS LA English DT Article DE bump hunting; graphical methods; kernel density estimation; multimodality; visualization ID DENSITY-ESTIMATION; KERNEL AB The mode tree of Minnotte and Scott provides a valuable method of investigating features such as modes and bumps in a unknown density. By examining kernel density estimates for a range of bandwidths, we can learn a lot about the structure of a data set. Unfortunately, the basic mode toe can be strongly affected by small changes in the data, and gives no way to differentiate between important modes and those caused, for example, by outliers. The mode forest overcomes these difficulties by looking simultaneously at a large collection of mode trees, all based on some variation of the original data, by means such as resampling or jittering. The resulting graphic tool is both visually appealing and informative. C1 Utah State Univ, Dept Math & Stat, Logan, UT 84322 USA. USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. George Mason Univ, Ctr Comp Stat, Fairfax, VA 22030 USA. RP Minnotte, MC (reprint author), Utah State Univ, Dept Math & Stat, Logan, UT 84322 USA. NR 19 TC 18 Z9 19 U1 0 U2 1 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 USA SN 1061-8600 J9 J COMPUT GRAPH STAT JI J. Comput. Graph. Stat. PD JUN PY 1998 VL 7 IS 2 BP 239 EP 251 DI 10.2307/1390816 PG 13 WC Statistics & Probability SC Mathematics GA ZW458 UT WOS:000074413000007 ER PT J AU Freitas, JA Nam, OH Zheleva, TS Davis, RF AF Freitas, JA Nam, OH Zheleva, TS Davis, RF TI Optical and structural properties of lateral epitaxial overgrown GaN layers SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 2nd International Conference on Nitride Semiconductors (ICNS 97) CY OCT 27-31, 1997 CL TOKUSHIMA CITY, JAPAN SP Japan Soc Appl Phys, Inst Electr Informat & Commun Engineers, IEEE, Electron Devices Soc ID RAMAN; FILMS AB The optical and microstructural properties of laterally grown GaN overlayers nucleated on GaN stripes by organometallic vapor-phase epitaxy have been investigated. TEM studies indicate that the high density of threading dislocations in the GaN substrate originating at the underlying interface of GaN with the AIN buffer layer, propagate through the window overgrown region. In contrast, the dislocation density is substantially lower in the laterally grown region. Spatially resolved Raman scattering results are consistent with improved material quality on the laterally overgrown region. Low-temperature photoluminescence measurements show that a shallow acceptor is present in the selectively grown region. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. RP Freitas, JA (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM freitas@bloch.nrl.navy.mil RI Davis, Robert/A-9376-2011 OI Davis, Robert/0000-0002-4437-0885 NR 9 TC 14 Z9 14 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 JUN PY 1998 VL 189 BP 92 EP 96 DI 10.1016/S0022-0248(98)00179-1 PG 5 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA ZZ448 UT WOS:000074730400021 ER PT J AU Carlos, WE Nakamura, S AF Carlos, WE Nakamura, S TI Magnetic resonance studies of GaN-based LEDs SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 2nd International Conference on Nitride Semiconductors (ICNS 97) CY OCT 27-31, 1997 CL TOKUSHIMA CITY, JAPAN SP Japan Soc Appl Phys, Inst Electr Informat & Commun Engineers, IEEE, Electron Devices Soc DE gallium nitride; magnetic resonance; LED; defects; EDMR; recombination ID LIGHT-EMITTING-DIODES; YELLOW LUMINESCENCE; GROWTH; DONORS; LAYERS AB Electrically detected magnetic resonance (EDMR), electrically excited and optically detected magnetic resonance, photocurrent-detected magnetic resonance and the photo-quenching of EDMR are employed to study radiative and non-radiative recombination processes in single quantum well diodes. The effects of high current stress are studied in addition to recombination in unstressed devices. The signals are dominated by a broad line (g approximate to 2.01; Delta B approximate to 13 mT) which can be optically quenched by absorption in the quantum well of the diode. Measurements on diodes which have been subjected to high current stressing reveal another resonance located in an area of the diode in series with the quantum well and these results also indicate that the broad line is due to more than one defect level. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Nichia Chem Ind Ltd, Tokushima 774, Japan. RP Carlos, WE (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM carlos@bloch.nrl.navy.mil NR 15 TC 1 Z9 1 U1 0 U2 7 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 JUN PY 1998 VL 189 BP 794 EP 797 DI 10.1016/S0022-0248(98)00296-6 PG 4 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA ZZ448 UT WOS:000074730400164 ER PT J AU Lange, MD Storm, DF Cole, T AF Lange, MD Storm, DF Cole, T TI Molecular-beam epitaxy of InTlAs SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT US Workshop on the Physics and Chemistry of II - VI Materials CY OCT 21-23, 1997 CL SANTA BARBARA, CALIFORNIA SP USA, CECOM, NVESD, USA, SSDC, USN, Off Naval Res, USAF, Air Force Wright Lab, Amer Phys Soc, Minerals, Metals & Mat Soc DE InAs; InTlAs; molecular-beam epitaxy (MBE); thallium; TlAs ID CHEMICAL-VAPOR-DEPOSITION; INFRARED DETECTOR MATERIAL; GROWTH; GAAS AB We have investigated growth of LnTlAs and TlAs by molecular-beam epitaxy (MBE) onto both InAs-buffered and unbuffered GaAs substrates. In accordance with more recent predictions by the theorists who originally proposed InTlAs and two other related thallium-based compounds for long-wave infrared applications, we have observed experimentally that incorporation of: thallium into InTlAs is indeed difficult by MBE. In fact, to date we have found a possible hint of appreciable InTlAs formation in only one of our attempted growths: one which was conducted at a growth temperature around 420 degrees C on a highly defective InAs buffer. However, TlAs formation (although highly defective) was apparently obtained at a growth temperature around 200 degrees C on a good InAs buffer. Moreover, although TI has proven to be very difficult to incorporate into InTlAs by MBE, we have discovered that the presence of a Tl flux during InAs growth consistency permits good growth of InAs, even at growth temperatures far below those normally optimal for InAs MBE. C1 USN, Phys Branch, Res & Technol Grp, Air Warfare Ctr,Weap Div, China Lake, CA 93555 USA. Univ Virgin Isl, Div Sci & Math, St Thomas, VI 00802 USA. RP Lange, MD (reprint author), USN, Phys Branch, Res & Technol Grp, Air Warfare Ctr,Weap Div, China Lake, CA 93555 USA. NR 18 TC 17 Z9 17 U1 0 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD JUN PY 1998 VL 27 IS 6 BP 536 EP 541 DI 10.1007/s11664-998-0011-9 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA ZV637 UT WOS:000074325800011 ER PT J AU Jordan, SA Ragab, SA AF Jordan, SA Ragab, SA TI A large-eddy simulation of the near wake of a circular cylinder SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID REYNOLDS-NUMBER; TURBULENT FLOWS; VORTICES; MODEL AB The formation and the downstream transport of the Strouhal vortices in the near wake of a circular cylinder are investigated using the large-eddy simulation (LES) method. The governing equations are formulated in curvilinear coordinates to accommodate a nonorthogonal grid with formal development of a dynamic model to account for the subgrid turbulent scales. Results were produced with and without use of the model. The focus of the investigation is at a subcritical Reynolds number of 5600. Using the dynamic model, the LES results compared best to the published experimental data in terms of bath the global and local wake characteristics such as the drag and base pressure coefficients, shedding and detection frequencies, peak vorticity, and the downstream mean velocity-defect and Reynolds stresses. The results further showed streamwise filaments that connect subsequent Strouhal vortices. Qualitatively, the time-averaged Reynolds stresses of the formation region revealed similar symmetric characteristics over the range 525 less than or equal to Re less than or equal to 140,000. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. RP Jordan, SA (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02841 USA. NR 32 TC 29 Z9 29 U1 0 U2 0 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 JUN PY 1998 VL 120 IS 2 BP 243 EP 252 DI 10.1115/1.2820640 PG 10 WC Engineering, Mechanical SC Engineering GA ZU129 UT WOS:000074165200002 ER PT J AU Amatucci, WE Walker, DN Ganguli, G Duncan, D Antoniades, JA Bowles, JH Gavrishchaka, V Koepke, ME AF Amatucci, WE Walker, DN Ganguli, G Duncan, D Antoniades, JA Bowles, JH Gavrishchaka, V Koepke, ME TI Velocity-shear-driven ion-cyclotron waves and associated transverse ion heating SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MICROWAVE PLASMA SOURCE; KINETIC ALFVEN WAVES; ELECTRIC-FIELD; ELECTROSTATIC-WAVES; MAGNETIC-FIELD; AURORAL ARC; ACCELERATED IONS; BLACK AURORA; F-REGION; INSTABILITY AB Recent sounding rocket experiments, such as SCIFER, AMICIST, and ARCS-4, and satellite data from FAST, Freja, DE-2, and HILAT, provide compelling evidence of a correlation between small-scale spatial plasma inhomogeneities, broadband low-frequency waves, and transversely heated ions. These naturally arising, localized inhomogeneities can lead to sheared cross-magnetic-field plasma flows, a situation that has been shown to have potential for instability growth. Experiments performed in the Naval Research Laboratory's Space Physics Simulation Chamber demonstrate that broadband waves in the ion-cyclotron frequency range can be driven solely by a transverse, localized electric field, without the dissipation of a field-aligned current. Significant perpendicular ion energization resulting from these waves has been measured. Detailed comparisons with both theoretical predictions and space observations of electrostatic waves found in the presence of sheared cross-magnetic-field plasma flow are made. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Sachs Freeman Associates Inc, Largo, MD 20774 USA. W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA. RP Amatucci, WE (reprint author), USN, Res Lab, Div Plasma Phys, Code 6700,4555 Overlook Ave SW, Washington, DC 20375 USA. EM amatucci@ccf.nrl.navy.mil NR 68 TC 55 Z9 56 U1 0 U2 3 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 JUN 1 PY 1998 VL 103 IS A6 BP 11711 EP 11724 DI 10.1029/98JA00659 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZQ564 UT WOS:000073880700014 ER PT J AU Harold, JB Chen, J Joyce, G AF Harold, JB Chen, J Joyce, G TI Resonance-generated particle distributions in magnetotail x line configurations SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY MAGNETIC-FIELD; TAIL CURRENT SHEET; NONLINEAR DYNAMICS; PLASMA SHEET; RECONNECTION; MOTION; MODEL; ENERGIZATION; SCATTERING; ORBITS AB We present the results of a series of test particle simulations that model particle acceleration both in self-consistent magnetospheric fields obtained by magnetohydrodynamic (MHD) simulations and in simple x line fields. In particular, we investigate the physical mechanisms responsible for the formation of beam-like features ("beamlets") in the accelerated outgoing particle distributions reported by previous authors. We find that in our simulations these effects arise from the x line, where the field gradients are strong; despite this finding they can be readily explained by using a simple analysis based on the phase space partitioning and resonances in one-dimensional current sheets, consistent with the conclusions of previous authors. We confirm the expected scaling using both two-and one-dimensional models of the x line with imposed uniform electric field. However, we find that the formation of these features is critically dependent on both the field geometry and the electric field imposed at the x line. In particular, use of an MHD-generated nonuniform electric field model eliminates the energized particle population, while use of current sheets with a self-consistent width blurs the features until they are no longer easily discernible. This finding calls into question the degree to which the beamlet structures (those that depend on magnetic field gradients along the tail with a uniform electric field) can be observed in physical systems. C1 USN, Res Lab, Beam Phys Branch, Div Plasma Phys, Washington, DC 20375 USA. RP Harold, JB (reprint author), Space Sci Inst, 1234 Innovat Dr, Boulder, CO 80303 USA. NR 31 TC 1 Z9 1 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 1998 VL 103 IS A6 BP 11887 EP 11906 DI 10.1029/97JA02261 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZQ564 UT WOS:000073880700027 ER PT J AU Warren, HP Mariska, JT Lean, J AF Warren, HP Mariska, JT Lean, J TI A new reference spectrum for the EUV irradiance of the quiet Sun 1. Emission measure formulation SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SOLAR EXTREME-ULTRAVIOLET; ENERGY-BALANCE; MODELS; CHROMOSPHERE; VARIABILITY; FLUX AB We present a quiet Sun irradiance spectrum from 50-1200 Angstrom based primarily on intensities computed from a newly constructed quiet Sun emission measure distribution. We derive the emission measure from a spectrum of a portion of the quiet solar disk measured with the Harvard instrument on Skylab and recent compilations of atomic data. For some specific emission lines and continua which are not optically thin and cannot be computed using an emission measure, we either use intensities from the Harvard spectrum directly or infer them from other observations. Application of a simple center-to-limb variation converts the intensities to equivalent full-disk quiet Sun fluxes. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP USN, Res Lab, EO Hulburt Ctr Space Res, 4555 Overlook Ave SW,Code 7673, Washington, DC 20375 USA. EM hpw@dogwood.nrl.navy.mil; mariska@aspen.nrl.navy.mil; lean@demeter.nrl.navy.mil OI Lean, Judith/0000-0002-0087-9639 NR 47 TC 49 Z9 49 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 1998 VL 103 IS A6 BP 12077 EP 12089 DI 10.1029/98JA00810 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZQ564 UT WOS:000073880700043 ER PT J AU Warren, HP Mariska, JT Lean, J AF Warren, HP Mariska, JT Lean, J TI A new reference spectrum for the EUV irradiance of the quiet Sun - 2. Comparisons with observations and previous models SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SOLAR EUV; LYMAN-ALPHA; IONIZATION FREQUENCIES; LINE; VARIABILITY; EMISSION; CYCLE-21; FLUXES AB In a companion paper we presented a new reference spectrum for the EUV irradiance of the quiet Sun based primarily on intensities calculated from a quiet Sun emission measure distribution and recent compilations of atomic data. The contributions of optically thick emission lines and continua were included empirically. In this paper we present comparisons between this reference spectrum and independently measured irradiance observations, previous quiet Sun reference spectra, and the predictions of empirical EUV irradiance models. These comparisons indicate relatively good agreement among fluxes of emission lines formed in the solar chromosphere and transition region. The fluxes for coronal emission lines in previous quiet Sun reference spectra, however, do not agree with our calculated fluxes or with a recent irradiance observation taken at a low level of solar activity. Coronal emission lines in the Atmospheric Explorer E (AE-E) quiet Sun reference spectrum SC21REFW have fluxes that are typically smaller than our calculated fluxes by factors of 2 or more. We also identify inconsistencies in the earlier reference spectrum of Heroux and Hinteregger [1978] (F74113), where the fluxes of many coronal emission lines with wavelengths below 250 Angstrom are inconsistent with the fluxes of coronal emission lines at longer wavelengths. The fluxes of EUV continua in the various reference spectra and irradiance observations also differ significantly. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Warren, HP (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7673,4555 Overlook Ave SW, Washington, DC 20375 USA. OI Lean, Judith/0000-0002-0087-9639 NR 33 TC 27 Z9 27 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 JUN 1 PY 1998 VL 103 IS A6 BP 12091 EP 12102 DI 10.1029/98JA00811 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZQ564 UT WOS:000073880700044 ER PT J AU McCoskey, SK Selden, TM AF McCoskey, SK Selden, TM TI Health care expenditures and GDP: panel data unit root test results SO JOURNAL OF HEALTH ECONOMICS LA English DT Article DE health care expenditures; panel data; stationarity; unit roots ID CONVERSION FACTOR INSTABILITY; INTERNATIONAL COMPARISONS; TIME-SERIES; DETERMINANTS; COUNTRIES AB This short paper presents unit root test results for time series on per capita national health care expenditures and gross domestic product in the OECD. Unlike the country-by-country test used by [Hansen, P., King, A., 1996, The determinants of health care expenditure: A cointegration approach. J. Health Econ, 15, 127-137], the test we employ exploits the panel nature of the OECD data. Using this approach, we are able to reject the null hypothesis that these series contain unit roots. No single test is likely to be definitive in this rapidly-evolving area of econometric research; however, our results help to mitigate concern that panel data analyses of national health care expenditures an misspecified. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Agcy Hlth Care Policy & Res, Ctr Cost & Financing Studies, Rockville, MD 20852 USA. USN Acad, Dept Econ, Annapolis, MD 21402 USA. RP Selden, TM (reprint author), Agcy Hlth Care Policy & Res, Ctr Cost & Financing Studies, 2101 E Jefferson St,Suite 500, Rockville, MD 20852 USA. NR 26 TC 69 Z9 70 U1 3 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6296 J9 J HEALTH ECON JI J. Health Econ. PD JUN PY 1998 VL 17 IS 3 BP 369 EP 376 DI 10.1016/S0167-6296(97)00040-4 PG 8 WC Economics; Health Care Sciences & Services; Health Policy & Services SC Business & Economics; Health Care Sciences & Services GA ZW170 UT WOS:000074382700006 PM 10180923 ER PT J AU Ockenhouse, CF Sun, PF Lanar, DE Wellde, BT Hall, BT Kester, K Stoute, JA Magill, A Krzych, U Farley, L Wirtz, RA Sadoff, JC Kaslow, DC Kumar, S Church, LWP Crutcher, JM Wizel, B Hoffman, S Lalvani, A Hill, AVS Tine, JA Guito, KP de Taisne, C Anders, R Horii, T Paoletti, E Ballou, WR AF Ockenhouse, CF Sun, PF Lanar, DE Wellde, BT Hall, BT Kester, K Stoute, JA Magill, A Krzych, U Farley, L Wirtz, RA Sadoff, JC Kaslow, DC Kumar, S Church, LWP Crutcher, JM Wizel, B Hoffman, S Lalvani, A Hill, AVS Tine, JA Guito, KP de Taisne, C Anders, R Horii, T Paoletti, E Ballou, WR TI Phase I/IIa safety, immunogenicity, and efficacy trial of NYVAC-Pf7, a pox-vectored, multiantigen, multistage vaccine candidate for Plasmodium falciparum malaria SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID GENETICALLY ENGINEERED POXVIRUSES; GLYCOPROTEIN-D; BIOLOGICAL-ACTIVITY; ESCHERICHIA-COLI; ENVELOPE GENE; LIVE VACCINES; VIRUS; PROTECTION; PROTEIN; HERPES AB Candidate malaria vaccines have failed to elicit consistently protective immune responses against challenge with Plasmodium falciparum. NYVAC-Pf7, a highly attenuated vaccinia virus with 7 P. falciparum genes inserted into its genome, was tested in a phase I/IIa safety, immunogenicity, and efficacy vaccine trial in human volunteers. Malaria genes inserted into the NYVAC genome encoded proteins from all stages of the parasite's life cycle. Volunteers received three immunizations of two different dosages of NYVAC-Pf7. The vaccine was safe and well tolerated but variably immunogenic. While antibody responses were generally poor, cellular immune responses were detected in >90% of the volunteers. Of the 35 volunteers challenged with the bite of 5 P. falciparum-infected Anopheles mosquitoes, 1 was completely protected, and there was a significant delay in time to parasite patency in the groups of volunteers who received either the low or high dose of vaccine compared with control volunteers. C1 Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Dept Immunol, Washington, DC 20307 USA. USN, Med Res Inst, Malaria Program, Bethesda, MD USA. NIAID, Parasit Dis Lab, NIH, Bethesda, MD 20892 USA. Univ Oxford, Inst Mol Med, Oxford, England. Virogenet Corp, Troy, NY USA. Connaught Labs Inc, Swiftwater, PA 18370 USA. Pasteur Merieux Connaught, Marcy Letoile, France. Walter & Eliza Hall Inst Med Res, Melbourne, Vic 3050, Australia. Osaka Univ, Microbial Dis Res Inst, Osaka, Japan. RP Ockenhouse, CF (reprint author), Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Dept Immunol, Washington, DC 20307 USA. EM LTC_Chris_Ockenhouse@wrsmtp-ccmail.army.mil RI HILL, Adrian/C-1306-2008; Kester, Kent/A-2114-2011; Lanar, David/B-3560-2011 OI Kester, Kent/0000-0002-5056-0802; NR 27 TC 167 Z9 176 U1 0 U2 4 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 JUN PY 1998 VL 177 IS 6 BP 1664 EP 1673 DI 10.1086/515331 PG 10 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZP618 UT WOS:000073771500030 PM 9607847 ER PT J AU Mayers, D Bethel, J Wainberg, MA Weislow, O Schnittman, S AF Mayers, D Bethel, J Wainberg, MA Weislow, O Schnittman, S CA Div AIDS Treat Res Init 003 Study Gr TI Human immunodeficiency virus proviral DNA from peripheral blood and lymph nodes demonstrates concordant resistance mutations to zidovudine (codon 215) and didanosine (codon 74) SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID REVERSE-TRANSCRIPTASE; COMBINATION THERAPY; DRUG-RESISTANCE; DISEASE; STAGE AB Genotypes that confer drug resistance were evaluated in human immunodeficiency virus (HIV) proviral DNA obtained from peripheral blood mononuclear cells (PBMC) and lymphoid tissue at baseline and after 8 weeks of therapy with zidovudine alone or in combination with didanosine from 22 patients (8 zidovudine-naive and 14 zidovudine-experienced). There was evidence of zidovudine resistance at codon 215 in 27.3% (6/22) of patients. All 20 patients evaluable for codon 74 (site of didanosine resistance) had virus that remained wild type during the 8-week study period, When HIV proviral DNA from PBMC was compared, with that from lymphoid tissue, 94.7% (18/19) of evaluable samples were concordant at codon 215 at baseline, while 85.7% (12/14) were concordant at week 8, Resistance in PBMC (but not in lymphoid tissue) developed in 1 of 8 zidovudine-naive patients; an increased proportion of resistant strains in PBMC (but not in lymphoid tissue) was observed in 2 of 14 zidovudine-experienced patients. These results suggest high concordance for drug resistance mutations in HIV proviral DNA from blood and lymph node tissue. C1 USN, Med Res Inst, Bethesda, MD USA. NIAID, Div Aids, NIH, Bethesda, MD 20892 USA. WESTAT Inc, Rockville, MD USA. SRA Technol, Rockville, MD USA. Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Washington, DC 20307 USA. Sir Mortimer B Davis Jewish Hosp, Montreal, PQ H3T 1E2, Canada. RP Mayers, D (reprint author), 8901 Wisconsin Ave,POB 207, Bethesda, MD 20889 USA. FU NIAID NIH HHS [AI-15123] NR 15 TC 6 Z9 6 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 JUN PY 1998 VL 177 IS 6 BP 1730 EP 1733 DI 10.1086/517433 PG 4 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZP618 UT WOS:000073771500042 PM 9607859 ER PT J AU Fryauff, DJ Cryz, SJ Widjaja, H Mouzin, E Church, LWP Sutamihardja, MA Richards, AL Subianto, B Hoffman, SL AF Fryauff, DJ Cryz, SJ Widjaja, H Mouzin, E Church, LWP Sutamihardja, MA Richards, AL Subianto, B Hoffman, SL TI Humoral immune response to tetanus-diphtheria vaccine given during extended use of chloroquine or primaquine malaria chemoprophylaxis SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID CELL RABIES VACCINE; ANTIBODY-RESPONSE; PROPHYLAXIS; FALCIPARUM AB Immune suppression resulting from prolonged chemoprophylaxis and potential drug-vaccine interaction were investigated within the context of a randomized placebo-controlled trial that compared daily primaquine or meekly chloroquine administration for malaria prevention. After 11 months of prophylaxis, adult male subjects received a tetanus-diphtheria (Td) vaccination. Prophylaxis continued 4 weeks longer, Anti-tetanus and anti-diphtheria antibody levels were measured by ELISA at baseline and at 1, 3, 7, and 14 months after Td vaccination. All groups were comparable at baseline. Immunization triggered significant increases in anti-tetanus and anti-diphtheria IgG levels over each group's pre-Td baseline levels and those of an unvaccinated control group. Geometric mean anti-tetanus titers (GMTs) in the primaquine group mere significantly higher than those of the placebo group at 1, 3, and 14 months. Anti-tetanus GMTs in placebo and chloroquine groups declined over 14 months to levels comparable to those of unvaccinated controls, but levels in the primaquine group remained significantly higher than in controls. C1 USN, Med Res Unit 2, Jakarta, Indonesia. Prov Hlth Serv, Irian Jaya, Indonesia. Swiss Serum & Vaccine Inst, CH-3001 Bern, Switzerland. USN, Med Res Inst, Bethesda, MD USA. RP Fryauff, DJ (reprint author), NAMRU 2, Box 3,Unit 8132, APO, AP 96520 USA. NR 15 TC 8 Z9 8 U1 0 U2 0 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 JUN PY 1998 VL 177 IS 6 BP 1762 EP 1765 DI 10.1086/517441 PG 4 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZP618 UT WOS:000073771500050 PM 9607867 ER PT J AU Le, TP Hoffman, SL AF Le, TP Hoffman, SL TI Clinical manifestations of Plasmodium falciparum malaria - Reply SO JOURNAL OF INFECTIOUS DISEASES LA English DT Letter C1 USN, Med Res Inst, Malaria Program, Rockville, MD 20859 USA. RP Hoffman, SL (reprint author), USN, Med Res Inst, Malaria Program, 12300 Washington Ave, Rockville, MD 20859 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 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 JUN PY 1998 VL 177 IS 6 BP 1777 EP 1777 DI 10.1086/517424 PG 1 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZP618 UT WOS:000073771500063 ER PT J AU Carter, AC Chang, W Qadri, SB Horwitz, JS Leuchtner, R Chrisey, DB AF Carter, AC Chang, W Qadri, SB Horwitz, JS Leuchtner, R Chrisey, DB TI Micron thick epitaxial (100) Ag film growth on MgO SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID PULSED LASER DEPOSITION AB Epitaxial films of (100) Ag were deposited onto (100) MgO substrates to a thickness of 4 mu m with no evidence of (Ill)nucleation. Deposited films were smooth and had large areas, 50 X 50 microns square, free of morphological defects. Films were deposited using a two-step process. First, pulsed laser deposition was used to grow a 1000 Angstrom AE (100) seed layer on the MgO substrate. Second, e-beam evaporation was used to grow the film to the desired thickness. The high quality of the resulting films will allow them to be used as templates for further epitaxial deposition of other applied materials. C1 USN, Res Lab, Washington, DC 20375 USA. RP Carter, AC (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 16 TC 19 Z9 19 U1 1 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD JUN PY 1998 VL 13 IS 6 BP 1418 EP 1421 DI 10.1557/JMR.1998.0201 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA ZT232 UT WOS:000074063800003 ER PT J AU Lin, RQ AF Lin, RQ TI Comments on "The Goddard coastal wave model. Part I: Numerical method" - Reply: Part I SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Editorial Material ID FLUX-CORRECTED TRANSPORT; UNSTEADY; PHYSICS C1 Carderock Div, NSWC, Bethesda, MD 20817 USA. RP Carderock Div, NSWC, Code 5500,David Taylor Model Basin,9500 MacArthur, Bethesda, MD 20817 USA. EM rlin@wave2.dt.navy.mil NR 30 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 EI 1520-0485 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD JUN PY 1998 VL 28 IS 6 BP 1291 EP 1304 DI 10.1175/1520-0485(1998)028<1291:RPI>2.0.CO;2 PG 14 WC Oceanography SC Oceanography GA ZU133 UT WOS:000074165600016 ER PT J AU Lin, RQ AF Lin, RQ TI Comments on "The Goddard Coastal Wave Model. Part II: Kinematics" - Reply: Part II SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Editorial Material ID AMPLITUDE WATER-WAVES; GRAVITY-WAVES; WIND-WAVES; INSTABILITIES; UNSTEADY; CURRENTS; DEPTHS; TIDES C1 Carderock Div, W Bethesda, MD 20817 USA. RP Lin, RQ (reprint author), Carderock Div, Code 5500,David Taylor Model Basin,9500 MacArthur, W Bethesda, MD 20817 USA. EM rlin@wave2.dt.navy.mil NR 26 TC 1 Z9 1 U1 0 U2 0 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 JUN PY 1998 VL 28 IS 6 BP 1309 EP 1318 DI 10.1175/1520-0485(1998)028<1309:RPI>2.0.CO;2 PG 10 WC Oceanography SC Oceanography GA ZU133 UT WOS:000074165600018 ER PT J AU Maidanik, G Becker, KJ AF Maidanik, G Becker, KJ TI Various loss factors of a master harmonic oscillator coupled to a number of satellite harmonic oscillators SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID STRUCTURAL FUZZY AB Three loss factors are defined for a master harmonic oscillator (HO); the I-loss factor, the U-loss factor, and the effective loss factor. A conductance (beta) is conventionally defined as the ratio of the power imparted to a dynamic system by an external drive to the stored energy that this input power generates. The conductance (beta) is related to the loss factor (eta) by the frequency (omega); beta = (omega eta). In light of this definition, it is shown that all three loss factors are identical for an isolated master HO at resonance. Differences arise among these loss factors when the master HO is coupled to satellite harmonic oscillators (HO's). The first two loss factors retain their definitive format in the sense that the stored energy is reckoned only in the master HO; the energy stored in the coupled satellite HO's and in the couplings is discounted. The effective loss factor, on the other hand, is defined by accounting for the total stored energy that the external drive applied to the master HO generates in the complex. The complex here is composed of the master HO, the satellite HO's, and the in situ couplings. In those situations in which the portion of the total energy stored in the satellite HO's and in the couplings substantially exceeds the stored energy in the master HO, the I-loss factor and the U-loss factor may substantially exaggerate the true loss factor of the coupled master HO. Situations of this type are illustrated by data obtained in computational experiments, and it is argued that the true loss factor of the master HO in the complex as a whole is the effective loss factor. C1 NSWC, CD, DTMB, W Bethesda, MD 20817 USA. RP Maidanik, G (reprint author), NSWC, CD, DTMB, 9500 MacArthur Blvd, W Bethesda, MD 20817 USA. NR 17 TC 10 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 1998 VL 103 IS 6 BP 3184 EP 3195 DI 10.1121/1.423035 PG 12 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZT999 UT WOS:000074151200006 ER PT J AU Feuillade, C Nero, RW AF Feuillade, C Nero, RW TI A viscous-elastic swimbladder model for describing enhanced-frequency resonance scattering from fish SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID ACOUSTIC SCATTERING; STRENGTH; BUBBLES AB Acoustic scattering from many species of fish is strongly increased by the resonance response of the swimbladder. This gas-filled, elastic-walled internal sac may have several functions, including hearing and buoyancy. A complete physical description of the response must include the swimbladder wall, the surrounding flesh, and the gas enclosed. This work presents a new mathematical/physical model to describe resonance scattering from swimbladder fish. The model consists of a spherical air bubble enclosed, first, by an elastic shell (representing the swimbladder wall), and then by a viscous shell (representing the surrounding fish flesh). The rigidity of the inner shell increases the monopole resonance frequency of the bubble. The viscosity of the outer shell causes the resonance to be damped. By allowing these factors to vary within physically reasonable bounds, the new model has been used to explain the experimentally measured resonance frequencies and damping of swimbladder resonances in Atlantic cod. The model provides insights into the physiological mechanisms by which fish may actively control the resonance frequencies of their swimbladders to improve hearing, and how this control can be lost under varying water pressure conditions. The impact of this issue on fisheries survey procedures is discussed. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Feuillade, C (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 36 TC 27 Z9 30 U1 1 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 JUN PY 1998 VL 103 IS 6 BP 3245 EP 3255 DI 10.1121/1.423076 PG 11 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZT999 UT WOS:000074151200014 ER PT J AU Norton, GV Novarini, JC Keiffer, RS AF Norton, GV Novarini, JC Keiffer, RS TI Modeling the propagation from a horizontally directed high-frequency source in shallow water in the presence of bubble clouds and sea surface roughness SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SOUND-PROPAGATION; OCEAN; SCATTERING; EQUATION; WAVES AB Among the many factors affecting the propagation of sound in shallow water, surface-generated microbubbles have remained virtually unexplored. The collection of microbubbles, bubbles which usually do not result in a uniform layer, presents a complex structure that varies not only in depth but also in range, and can be characterized as a collage of bubble clouds. A numerical procedure is developed in which the bubble clouds are modeled following a classification scheme proposed by Monahan [Natural Physical Sources of Underwater Sound, edited by B. V. R. Kerman (Kluwer Academic, Dordrecht, 1993), pp. 503-517]. An effective complex index of refraction of the bubble mixture is calculated for each point of the resulting range-dependent environment. The combined effect that the sea surface roughness and the bubbly environment have on forward propagation is then modeled through a high fidelity model [Norton et al., J. Acoust. Sec. Am. 97, 2173-2180 (1995)] which combines a finite element Parabolic Equation model with conformal mapping to handle surface roughness. The case of a horizontally directed source, operating at 20 kHz for a single realization of a shallow water environment is analyzed in detail. The presence of the bubble clouds severely affects the amplitude near the surface, but their influence rapidly diminishes in depth. For the case considered, the surface roughness, which has little effect on the transmission loss of the propagating field, is, however, responsible for interference effects of the forward field observed throughout the water column, while ignoring the rough surface and bubble clouds leads to a 12-15 dB error in the acoustic field near the surface, at a range of 150 m. To assume a uniformly stratified (range independent) bubble layer results in large errors near the surface at the location of the high void fraction packets, but is an acceptable approximation away from these features. (C) 1998 Acoustical Society of America. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Planning Syst Inc, Long Beach, MS 39560 USA. RP USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 27 TC 8 Z9 9 U1 1 U2 2 PU ACOUSTICAL SOC AMER AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0001-4966 EI 1520-8524 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 1998 VL 103 IS 6 BP 3256 EP 3267 DI 10.1121/1.423042 PG 12 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZT999 UT WOS:000074151200015 ER PT J AU Collins, JA Broda, JE Purdy, GM Gaspin, J Griffin, T Peletski, C Lipton, L Baudler, B AF Collins, JA Broda, JE Purdy, GM Gaspin, J Griffin, T Peletski, C Lipton, L Baudler, B TI Source signature measurements of underwater explosives at very high ambient pressures SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID EAST PACIFIC RISE; SEISMIC TOMOGRAPHY; 9-DEGREES-30'N; CRUST AB The interpretation of seismic refraction experiments carried out on the deep-ocean floor has been hampered by lack of knowledge of the source signatures of explosives at these high ambient pressures. In order to fully exploit the data from such experiments, the source signatures of four explosives detonated at deep water depths have been measured. The explosives were commercially available Pentolite and three U.S. Navy explosives: PBXN-103, PBXN-111, and PBXW-127. A total of 75 similar to 10 Ib (4.54 kg) charges were detonated at depths of 2350-4593 m, and the source signatures were recorded at offset ranges of 160-230 m. For all four explosives, the period of the first oscillation follows the theoretically established relationship T=K*M-1/3(Z+10)(-5/6), where T is the period (s), M is the charge mass (kg), and Z is the detonation depth (m). The optimum value of K for Pentolite (2.07+/-0.01 s m(5/6) kg(-1)) is identical to the value previously reported from the analysis of explosives detonated at depths of less than a few hundred meters. The optimum values for PBXN-103, PBXN-111, and PBXW-127 are 2.67+/-0.01 s m(5/6) kg(-1), 2.64+/-0.01 s m(5/6) kg-l and 2.73+/-0.01 s m(5/6) kg(-1), respectively. The greater bubble pulse period of the PBX-based explosives means that they are richer in low-frequency energy than Pentolite. The total energy flux in the frequency band 30-100 Hz is similar to 6 dB greater for the PBX-based explosives than that for Pentolite at all detonation depths. (C) 1998 Acoustical Society of America. C1 Woods Hole Oceanog Inst, Dept Geol & Geophys, Woods Hole, MA 02543 USA. Natl Sci Fdn, Div Ocean Sci, Washington, DC 20550 USA. USN, Ctr Surface Warfare, Indian Head Div, Silver Spring, MD 20903 USA. RP Collins, JA (reprint author), Woods Hole Oceanog Inst, Dept Geol & Geophys, Woods Hole, MA 02543 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 1998 VL 103 IS 6 BP 3281 EP 3289 DI 10.1121/1.423079 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZT999 UT WOS:000074151200017 ER PT J AU Moffett, MB Powers, JM Jevnager, MD AF Moffett, MB Powers, JM Jevnager, MD TI A tonpilz projector for use in an underwater horn SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB Tonpilz transducer head piston diameters are usually about one-half wavelength in diameter, so that "rho-c" radiation loading will be approximately achieved. However, for this underwater tracking application, the transducer is required to fit inside the throat of a 360-degree horn. The piston diameter is limited to 1 in. (25 mm), or about 0.22 wavelength at the resonance frequency, 13 kHz. The design is based on a lumped-element model. The lead zironate-titanate (PZT-8) ring stack is 2.1 in. (53 mm) long with an outer diameter of 0.49 in. (12.5 mm) and an inner diameter of 0.24 in. (6.0 mm). The head mass is 0.25-in. (0.635-mm)-thick aluminum, and the tail mass is wolfram (tungsten), with a mass of 93 g. The transducer is isolated from its cylindrical housing with a syntactic foam spring. An O-ring piston seal is used, and a similar O-ring provides support for the tail mass. The results of free-field measurements are used to determine the parameters of a lumped-parameter equivalent circuit model, which is then used to predict the performance after installation in the horn. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. RP Moffett, MB (reprint author), USN, Undersea Warfare Ctr, Code 2131, Newport, RI 02841 USA. NR 17 TC 1 Z9 1 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 JUN PY 1998 VL 103 IS 6 BP 3353 EP 3361 DI 10.1121/1.423049 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZT999 UT WOS:000074151200025 ER PT J AU Harrison, BF Vaccaro, RJ Tufts, DW AF Harrison, BF Vaccaro, RJ Tufts, DW TI Robust matched-field localization in uncertain ocean environments SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Letter AB Matched-field source localization methods can be sensitive to environmental parameter mismatch. A statistically optimal approach to source localization in the presence of environmental uncertainty is the maximum a posteriori probability (MAP) estimator. Unfortunately, practical implementation of the MAP estimator results in a computationally intensive processor. In this paper, a localization technique is presented that is a computationally efficient approximation to the MAP estimator. A two-step search procedure is used to estimate source position. The first step utilizes an approximation to the MAP estimator which allows much of the computation to be computed efficiently off-line. This step also includes a computationally efficient range-depth smoothing which provides robustness to grid density. In step two, ambiguities arising from step one are resolved using a fine-grid search procedure over the source location parameters. Simulations using the NRL Workshop benchmark environment, which has seven uncertain environmental parameters, show the performance of the technique to be comparable to that of the MAP estimator while requiring only a fraction of the computations. (C) 1998 Acoustical Society of America. C1 USN, Undersea Warfare Ctr, Submarine Sonar Dept, Newport, RI 02841 USA. Univ Rhode Isl, Dept Elect Engn, Kingston, RI 02881 USA. RP Harrison, BF (reprint author), USN, Undersea Warfare Ctr, Submarine Sonar Dept, Newport, RI 02841 USA. NR 8 TC 4 Z9 4 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 JUN PY 1998 VL 103 IS 6 BP 3721 EP 3724 DI 10.1121/1.423091 PG 4 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZT999 UT WOS:000074151200059 ER PT J AU Xu, Q Gao, JD Gu, W AF Xu, Q Gao, JD Gu, W TI Generalized adjoint for physical processes with parameterized discontinuities. Part V: Coarse-grain adjoint and problems in gradient check SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article AB When on/off switches are triggered at discrete time levels by a threshold condition in a traditionally discretized model, the model solution is not continuously dependent on the initial state and this causes problems in tangent linearization and adjoint computations. It is shown in this paper that the problems can be avoided by introducing coarse-grain tangent linearization and adjoint without modifying the traditional discretization, although the coarse-grain gradient check can be performed only for finite perturbations. C1 USN, Res Lab, Monterey, CA 93943 USA. Univ Oklahoma, CAPS, Norman, OK 73019 USA. Univ Oklahoma, CIMMS, Norman, OK 73019 USA. Nanjing Univ, Dept Atmospher Sci, Nanjing 210008, Peoples R China. RP Xu, Q (reprint author), USN, Res Lab, 7 Grace Hopper Dr, Monterey, CA 93943 USA. NR 5 TC 14 Z9 16 U1 0 U2 1 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 1 PY 1998 VL 55 IS 11 BP 2130 EP 2135 DI 10.1175/1520-0469(1998)055<2130:GAFPPW>2.0.CO;2 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZT491 UT WOS:000074093200015 ER PT J AU Cronce, DT Famini, GR De Soto, JA Wilson, LY AF Cronce, DT Famini, GR De Soto, JA Wilson, LY TI Using theoretical descriptors in quantitative structure-property relationships: some distribution equilibria SO JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 LA English DT Article ID PARTITION-COEFFICIENTS; BIOCHEMICAL PROCESSES; HEXADECANE; GAS AB The partition coefficients [equilibrium constants, K, for X(g) <-> X(solvent, substrate)] for a large (326) set of compounds in hexadecane, olive oil and polymers as solvents correlate well with a set of theoretical (computational) molecular parameters using a theoretical linear solvation energy relationship (TLSER). The correlation equations are physically reasonable and may be used as probes for solute-solvent interactions. Results from the regression analyses are presented and discussed, describing how specific characteristics of the solutes and solvents may be responsible for the significant molecular parameters of the TLSER correlations. C1 USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. USA, Edgewood Res Dev & Engn Ctr, Aberdeen Proving Ground, MD 21010 USA. La Sierra Univ, Dept Chem, Riverside, CA 92515 USA. RP Cronce, DT (reprint author), USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. NR 24 TC 36 Z9 36 U1 0 U2 3 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE CB4 4WF, CAMBS, ENGLAND SN 0300-9580 J9 J CHEM SOC PERK T 2 JI J. Chem. Soc.-Perkin Trans. 2 PD JUN PY 1998 IS 6 BP 1293 EP 1301 PG 9 WC Chemistry, Organic; Chemistry, Physical SC Chemistry GA ZV136 UT WOS:000074273000004 ER PT J AU Kolman, DG Gaudett, MA Scully, JR AF Kolman, DG Gaudett, MA Scully, JR TI Modeling of anodic current transients resulting from oxide rupture of plastically strained beta+alpha titanium SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID STRESS-CORROSION CRACKING; AQUEOUS CHLORIDE SOLUTIONS; SURFACE CURRENT DENSITIES; 304L STAINLESS-STEEL; SCRATCHED ELECTRODE; FILM GROWTH; REPASSIVATION; BETA; BEHAVIOR; KINETICS AB The film rupture behavior on dynamically strained Ti-15 Mo-3 Nb-3 Al exposed to 0.6 M NaCl has been examined by rapid data acquistion of anodic current transients. The anodic current transients resulted from dislocation intersection of the passive film, followed by film rupture, bare surface dissolution, and repassivation. The transient morphology during dynamic straining differs from that generated via conventional depassivation techniques (i.e., manual scratch and fractured thin film depassivation) which incorporate an electrode that does not experience active plastic straining following depassivation. During conventional depassivation testing, current transients increase relatively rapidly and decay with an approximately linear slope on the log i-log t plot. In contrast, the transients acquired during dynamic straining are characterized by a relatively slow current increase and a nonlinear current decay on the log i-log t plot. This nonlinear decay is not attributable to ohmic or capacitive effects. The difference between the anodic transient morphologies on dynamically strained and unstrained electrodes is attributed to the combination of many discrete dislocation intersections of the surface over a period which is much larger than the time required for repassivation of a single dislocation intersection. Additionally, atomic force microscopy revealed persistent slip on a limited number of slip planes, with slip offsets as large as 600 nm, which is consistent with the formation and emergence of superdislocations. Thus, film rupture results from sc-face intersection of a superdislocation comprised of individual dislocations which are spatially and temporally separated. Current transient modeling of superdislocation intersection agrees qualitatively with that observed experimentally. It is concluded that the repassivation behavior determined by conventional depassivation techniques may not be relevant for modeling of environmentally assisted cracking of dynamically strained electrodes in some cases. C1 Univ Calif Los Alamos Natl Lab, Mat Corros & Environm Effects Lab, Los Alamos, NM 87545 USA. USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. Univ Virginia, Dept Mat Sci & Engn, Ctr Electrochem Sci & Engn, Charlottesville, VA 22903 USA. RP Kolman, DG (reprint author), Univ Calif Los Alamos Natl Lab, Mat Corros & Environm Effects Lab, POB 1663, Los Alamos, NM 87545 USA. RI Street, Steven/A-5398-2015 OI Street, Steven/0000-0002-8999-3701 NR 72 TC 22 Z9 22 U1 0 U2 6 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 JUN PY 1998 VL 145 IS 6 BP 1829 EP 1840 DI 10.1149/1.1838564 PG 12 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZN999 UT WOS:000073705200004 ER PT J AU Tran, P Elson, JM AF Tran, P Elson, JM TI Banded method of ordered multiple interaction for the scattering of electromagnetic waves from a rough surface SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID MONTE-CARLO SIMULATIONS; MATRIX ITERATIVE APPROACH; BACKSCATTERING ENHANCEMENT; RANDOMLY ROUGH; NUMERICAL-SIMULATION AB We present a banded method of ordered multiple interaction (MOMI) for the scattering of electromagnetic waves by a one-dimensional, perfectly conducting, randomly rough surface. The forward and backward substitution of the MOMI is carried out with a banded-matrix forward and backward substitution approach that scales as N log N for large N, where N is the number of unknowns. (C) 1998 Optical Society of America. C1 USN, Air Warfare Ctr, Weapons Div, Res & Technol Grp, China Lake, CA 93555 USA. RP Tran, P (reprint author), USN, Air Warfare Ctr, Weapons Div, Res & Technol Grp, Code 4B4000D, China Lake, CA 93555 USA. NR 22 TC 4 Z9 4 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD JUN PY 1998 VL 15 IS 6 BP 1643 EP 1646 DI 10.1364/JOSAA.15.001643 PG 4 WC Optics SC Optics GA ZP471 UT WOS:000073756800017 ER PT J AU Asher, W Wang, Q Monahan, EC Smith, PM AF Asher, W Wang, Q Monahan, EC Smith, PM TI Estimation of air-sea gas transfer velocities from apparent microwave brightness temperature SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article ID EXCHANGE; TRACER; MODEL AB Oceanic measurements of air-sea gas transfer velocities, wind speed, and fractional area whitecap coverage have shown that gas transfer rates are a function of both whitecap coverage and wind speed. The microwave emissivity of the sea surface is also known to be a function of these same environmental forcing functions. Therefore, it could be possible to estimate transfer velocities from microwave brightness temperatures measured by satellite-mounted or aircraft-borne radiometers. This hypothesis is supported by concurrent microwave radiometric and gas transfer data collected in a surf pool. In this paper, the average microwave emissivity of simulated breaking waves was measured at 19 GHz for horizontally and vertically polarized radiation. The emissivities were used in a sim-pie model for the microwave response of the ocean surface to calculate brightness temperatures. Brightness temperatures could then be calculated for specific wind speeds and whitecap coverages corresponding to the physical conditions for which oceanic meas urenments of the air-sea gas transfer velocity are available. Comparing the increase in the calculated brightness temperatures with the measured increase in transfer velocity shows that currently available microwave radiometers have the necessary precision for in situ measurement of gas transfer velocities. However, the relations developed here must be verified by direct concurrent measurement of brightness temperature and gas transfer under oceanic conditions. C1 Univ Washington, Appl Phys Lab, Seattle, WA 98105 USA. Univ Connecticut, Inst Marine Sci, Groton, CT USA. USN, Res Lab, Stennis Space Ctr, Stennis, MI USA. RP Univ Washington, Appl Phys Lab, Seattle, WA 98105 USA. NR 22 TC 11 Z9 12 U1 0 U2 0 PU MARINE TECHNOLOGY SOC INC PI COLUMBIA PA 5565 STERRETT PLACE, STE 108, COLUMBIA, MD 21044 USA SN 0025-3324 EI 1948-1209 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD SUM PY 1998 VL 32 IS 2 BP 32 EP 40 PG 9 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 122LK UT WOS:000076072900004 ER PT J AU Mouring, SE AF Mouring, SE TI Composites for naval surface ships SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article AB The U.S. Navy is incorporating composite materials into the fleet due to the many advantages of composite construction compared to steel and aluminum construction. These advantages include the reduction in life costs, corrosion resistance, high strength- and stiffness-to-weight ratios, ability to tailor, and improved stealth. Of particular interest to the Navy are weight reduction and non-magnetic and damping characteristics associated with composite construction. Increased payload and range and improved ship stability can be achieved with weight reduction while nonmagnetic and damping characteristics help reduce magnetic and acoustic signatures. Many challenges still remain including issues related to design and analysis, fabrication, environmental effects, repair/joining, and fire, smoke, and toxicity. This paper includes a review of recent composite naval applications and a discussion on technical challenges associated with composite construction of naval ships. C1 USN Acad, Dept Naval Architecture Ocean & Marine Engn, Annapolis, MD 21402 USA. RP Mouring, SE (reprint author), USN Acad, Dept Naval Architecture Ocean & Marine Engn, Annapolis, MD 21402 USA. NR 30 TC 3 Z9 3 U1 0 U2 1 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 SUM PY 1998 VL 32 IS 2 BP 41 EP 46 PG 6 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 122LK UT WOS:000076072900005 ER PT J AU McCormick, GH Owen, G AF McCormick, GH Owen, G TI A simple decision model of counterproliferation SO MATHEMATICAL AND COMPUTER MODELLING LA English DT Article DE decision theory; nuclear proliferation; counterproliferation; national security AB We develop a simple decision model of counterproliferation involving a status quo "incumbent" and a. nuclear "entrant". The problem is examined as a one-stage interaction in two phases: nuclear development and deployment. We examine the conditions that will influence the decision to move pre-emptively against a proliferator's nuclear program. Particular attention is given to the role of uncertainty in determining the expected costs of action at different points in the entrant's weapon's development and deployment cycle. The model permits us to determine the optimal time to act given varying levels of information concerning entrant behavior. In conclusion, we examine the tradeoffs between the expected costs of action and the costs of intelligence. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP McCormick, GH (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 30 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 0895-7177 J9 MATH COMPUT MODEL JI Math. Comput. Model. PD JUN PY 1998 VL 27 IS 12 BP 69 EP 84 DI 10.1016/S0895-7177(98)00073-9 PG 16 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA ZT630 UT WOS:000074107100004 ER PT J AU Armstrong, DW AF Armstrong, DW TI Metabolic and endocrine responses to cold air in women differing in aerobic capacity SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Article DE exercise; women; cold; endorphin; catecholamine; metabolism ID BETA-ENDORPHIN; WATER IMMERSION; HORMONAL RESPONSES; PHYSICAL-FITNESS; RESTING MEN; EXERCISE; EXPOSURE; AGE; SEX; THERMOREGULATION AB Purpose: The purpose of this study was to measure resting metabolic rate, plasma norepinephrine, and plasma immunoreactive beta endorphin during exposures to cold air during two consecutive 5-d periods, separated by 2 weekend days, in two groups of women differing in aerobic fitness. Methods: Plasma norepinephrine (NE), plasma immunoreactive beta-endorphin (IBE), and resting metabolic response (RMR) were measured during repeated exposures to 3.5 degrees C air in two groups of women differing in aerobic fitness. Ten women, separated into highly fit (HFW) and less fit (LFW) groups, sat in 22 degrees C air for 45 min followed by 45 min in 3.5 degrees C air each day during two consecutive 5-d periods separated by two weekend days. Results: Norepinephrine was not different between groups during warm air exposure; however, following 45 min of cold air, NE was two times higher in HFW compared with that in LFW (P < 0.001). Plasma IBE was elevated (P < 0.02) in HEW compared with that in LFW but was not affected by exposure to cold on any test day. Warm RMR was not different between groups and remained unchanged during the study period. Cold RMR was significantly higher in LFW compared with that in HFW (P < 0.01). Resting metabolic rate peaked at 30% of (V) over dot O-2peak in LFW by the 5th minute of cold exposure on day 1 before declining to 21% and remaining steady. In contrast, RMR in HFW peaked at about 13% and then fell to 9.4% before slowly increasing to 14% by the end of 45 min. On other test days HFW RMR increased to 14% of (V) over dot O-2peak and rose slowly through 45 min of cold exposure while LFW RMR peaked at 24% of (V) over dot O-2peak before declining to 20% and remaining steady. Conclusions: Our findings suggest that, in women, aerobic fitness alters the endocrine and metabolic responses to acute cold air exposure. The norepinephrine response is exaggerated in highly fit women exposed to cold but not the metabolic response. Immunoreactive beta endorphin was not affected by exposure to cold but was elevated in highly fit women. We further conclude that the temperature threshold for acclimation to cold air by women may be higher than the air temperature used in this study. C1 USN, Inst Med Res, Thermal Stress Program,Div Endocrinol, Dept Internal Med,Natl Naval Med Ctr, Bethesda, MD 20889 USA. RP Armstrong, DW (reprint author), USN, Inst Med Res, Thermal Stress Program,Div Endocrinol, Dept Internal Med,Natl Naval Med Ctr, Bldg 9,Rm 2381, Bethesda, MD 20889 USA. NR 41 TC 4 Z9 4 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD JUN PY 1998 VL 30 IS 6 BP 880 EP 884 DI 10.1097/00005768-199806000-00016 PG 5 WC Sport Sciences SC Sport Sciences GA ZT305 UT WOS:000074071100016 PM 9624646 ER PT J AU Esser, RH Dimoulas, A Strifas, N Christou, A Papanicolau, N AF Esser, RH Dimoulas, A Strifas, N Christou, A Papanicolau, N TI Materials interfaces in flip chip interconnects for optical components; performance and degradation mechanisms SO MICROELECTRONICS AND RELIABILITY LA English DT Article; Proceedings Paper CT 9th European Symposium on Reliability of Electron Devices, Failure Physics and Analysis (ESREF 98) CY 1998 CL COPENHAGEN, DENMARK ID BEHAVIOR AB Flip chip solder joint reliability is dependant on final microstructure. The interface between the solder and the underlying metallization is of primary concern since the majority of joint failures occur at or near the interface. We report the results of our investigation on the structure-property relationships of the as deposited metallization and electroplated Pb/Sn solder, as they affect failure mechanisms. Samples investigated were prepared by electron beam evaporation of a Cr/Cu/Au metallization. Electroplated solders were prepared using a high tin solder bath and current density of 3.2mA/cm(2). It is shown that interdiffusion and intermetallic formation between gold and copper occurs during evaporation deposition. It is also shown that a significant amount of interdiffusion and intermetallic formation between the tin in the solder and the seed layer metals (Cu and Au) occurs during the electroplating operation. It is believed that this is due largely to resistive heating of the samples. The degree of interdiffusion in the as deposited state determines the ultimate reliability of the flip chip solder bumps in an optical configuration. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. Univ Maryland, Ctr Optoelect Devices Interconnects & Packaging, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. RP Esser, RH (reprint author), Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. NR 16 TC 2 Z9 2 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0026-2714 J9 MICROELECTRON RELIAB JI Microelectron. Reliab. PD JUN-AUG PY 1998 VL 38 IS 6-8 BP 1307 EP 1312 DI 10.1016/S0026-2714(98)00131-0 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 129FZ UT WOS:000076454300075 ER PT J AU Scott, RD AF Scott, RD TI Kimmel, Short, McVay: Case studies in executive authority, law and the individual rights of military commanders SO MILITARY LAW REVIEW LA English DT Review C1 USN, Judge Advocate Gen Corp, Washington, DC 20350 USA. NR 198 TC 2 Z9 2 U1 0 U2 0 PU JUDGE ADVOCATE GENERALS SCHOOL PI CHARLOTTESVILLE PA US ARMY, CHARLOTTESVILLE, VA 22903-1781 USA SN 0026-4040 J9 MIL LAW REV JI Milit. Law Rev. PD JUN PY 1998 VL 156 BP 52 EP 199 PG 148 WC Law SC Government & Law GA ZW222 UT WOS:000074387900003 ER PT J AU Trent, LK Hurtado, SL AF Trent, LK Hurtado, SL TI Longitudinal trends and gender differences in physical fitness and lifestyle factors in career US Navy personnel (1983-1994) SO MILITARY MEDICINE LA English DT Article; Proceedings Paper CT 38th Navy Occupational Health and Preventive Medicine Workshop CY FEB 07-14, 1997 CL VIRGINIA BEACH, VIRGINIA AB This study examines long-term health and physical readiness trends in the U.S. Navy. We mailed lifestyle questionnaires to all participants in baseline studies between 1983 and 1989 who were still on active duty in 1994. Commands provided body composition and physical readiness test scores for the participants. Two longitudinal cohorts were created: an 8-year sample (N = 640) with matched data from 1986, 1989, and 1994; and an 11-year sample (N = 1,576), with data from 1983 and 1994. Analyses of both cohorts revealed significant improvements in cardiovascular fitness, muscle strength, exercise, lean body mass, dietary habits, and sleep, as well as significant decreases in tobacco and alcohol use and job stress. However, hypertension rates, percentage of body fat, and body mass index increased over time. Women's scores were significantly better than men's on a number of factors. Overall, these findings suggest that the Navy's health promotion efforts have had a significant positive effect on the fitness and health behaviors of career Navy men and women. C1 Naval Hlth Res Ctr, Hlth Sci & Epidemiol Dept, San Diego, CA 92186 USA. RP Trent, LK (reprint author), Naval Hlth Res Ctr, Hlth Sci & Epidemiol Dept, POB 85122, San Diego, CA 92186 USA. NR 27 TC 2 Z9 2 U1 0 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 JUN PY 1998 VL 163 IS 6 BP 398 EP 407 PG 10 WC Medicine, General & Internal SC General & Internal Medicine GA ZU485 UT WOS:000074202800014 PM 9640037 ER PT J AU Reed, RJ Martino, J Eyestone, SM Pugh, WM AF Reed, RJ Martino, J Eyestone, SM Pugh, WM TI The field hospital at Zagreb: Tri-service medical care in a peacekeeping operation SO MILITARY MEDICINE LA English DT Article AB The objective of this investigation was to provide military medical planners with insights into the specific materiel, skills, and information requirements demanded by humanitarian missions through review of approximately 16,000 records from a tri-service medical patient database used at the held hospital in Zagreb, Croatia, during Operation Provide Promise. This review describes (1) the origin, rationale, structure, and implementation of the database; (2) the patients who used medical services provided by the hospital; (3) the diagnoses encountered in outpatient visits, admissions, and surgical operations; and (4) the distribution of medical services used by various subgroups of interest. C1 Naval Hlth Res Ctr, Med Informat Syst & Operat Res Dept, San Diego, CA 92186 USA. Battelle Mem Inst, Columbus, OH 43201 USA. Off Assistant Secretary Def Hlth Affairs, Washington, DC USA. RP Reed, RJ (reprint author), Naval Hlth Res Ctr, Med Informat Syst & Operat Res Dept, POB 85122, San Diego, CA 92186 USA. NR 10 TC 3 Z9 4 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 JUN PY 1998 VL 163 IS 6 BP 413 EP 419 PG 7 WC Medicine, General & Internal SC General & Internal Medicine GA ZU485 UT WOS:000074202800016 PM 9640039 ER PT J AU Carr, LE Elsberry, RL AF Carr, LE Elsberry, RL TI Objective diagnosis of binary tropical cyclone interactions for the western North Pacific basin SO MONTHLY WEATHER REVIEW LA English DT Article ID MOTION AB Objective criteria for distinguishing among three modes of binary tropical cyclone (TC) interactions (TCI) are defined and tested with an right-year sample of western North Pacific TCs. These objective criteria lead to an approximate 4:1 ratio of hits to misses of the subjectively assigned TCIs. False alarm rates of approximately 20% are also found, which indicate that similar track deflections may occur for other reasons, and the objective identifications must still be carefully validated by a forecaster. C1 USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Carr, LE (reprint author), USN, Postgrad Sch, Dept Meteorol, Code MR-Cr,589 Dyer Rd, Monterey, CA 93943 USA. NR 11 TC 23 Z9 33 U1 0 U2 4 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 JUN PY 1998 VL 126 IS 6 BP 1734 EP 1740 DI 10.1175/1520-0493(1998)126<1734:ODOBTC>2.0.CO;2 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 100UX UT WOS:000074834700021 ER PT J AU Harrison, JA Perry, SS AF Harrison, JA Perry, SS TI Friction in the presence of molecular lubricants and solid/hard coatings SO MRS BULLETIN LA English DT Article ID ATOMIC-SCALE FRICTION; CHEMICAL VAPOR-DEPOSITION; SLIDING FRICTION; ENERGY-DISSIPATION; DIAMOND COATINGS; DYNAMICS; MONOLAYERS; SIMULATIONS; ADHESION; FILMS C1 USN Acad, Annapolis, MD 21402 USA. Univ Houston, Dept Chem, Houston, TX 77004 USA. RP Harrison, JA (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 31 TC 38 Z9 39 U1 1 U2 7 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD JUN PY 1998 VL 23 IS 6 BP 27 EP 31 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA ZU489 UT WOS:000074203200022 ER PT J AU Singer, IL AF Singer, IL TI How third-body processes affect friction and wear SO MRS BULLETIN LA English DT Article ID DIAMOND-LIKE CARBON; DEBRIS FORMATION; BEHAVIOR; FILMS; COATINGS; DEPOSITION; CHEMISTRY; PRESSURES; CONTACT; VACUUM C1 USN, Res Lab, Div Chem, Tribol Sect, Washington, DC 20375 USA. RP Singer, IL (reprint author), USN, Res Lab, Div Chem, Tribol Sect, Washington, DC 20375 USA. NR 41 TC 48 Z9 49 U1 0 U2 6 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD JUN PY 1998 VL 23 IS 6 BP 37 EP 40 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA ZU489 UT WOS:000074203200024 ER PT J AU Carlson, CR Reid, KI Curran, SL Studts, J Okeson, JP Falace, D Nitz, A Bertrand, PM AF Carlson, CR Reid, KI Curran, SL Studts, J Okeson, JP Falace, D Nitz, A Bertrand, PM TI Psychological and physiological parameters of masticatory muscle pain SO PAIN LA English DT Article DE masticatory muscle pain; pressure stimulation; psychosocial stressor; laboratory challenge ID MYOFASCIAL PAIN; TEMPOROMANDIBULAR DISORDERS; DYSFUNCTION SYNDROME; PSYCHOPHYSIOLOGICAL RESPONSES; TMD PATIENTS; STRESS; FATIGUE; RELIABILITY; THRESHOLDS; REACTIVITY AB The objective of this research was to identify the psychological and physiological variables that differentiate persons reporting masticatory muscle pain (MMP) from normal controls (NC). This study examined the characteristics of 35 MMP patients in comparison to 35 age-, sex-, and weight-matched NCs. All subjects completed a series of standardized questionnaires prior to undergoing a laboratory evaluation consisting of a psychosocial stressor and pressure pain stimulation at multiple body sites. During the evaluation, subjects' emotional and physiological responses (heart rate, blood pressure, respiration, skin temperature, and muscle activity) were monitored. Results indicated that persons with MMP reported greater fatigue, disturbed sleep, depression, anxiety, menstrual symptoms, and less self-deception (P's < 0.05) than matched controls. At rest, MMPs had lower end tidal carbon dioxide levels (P < 0.04) and lower diastolic blood pressures than the NCs (P < 0.02). During laboratory challenge, both groups responded to the standard stressor with significant physiological activity and emotional responding consistent with an acute stress response (P < 0.01), but there were no differences between the MMPs and NCs. Muscle pain patients reported lower pressure pain thresholds than did NCs at the right/left masseter and right temporalis sites (P's < 0.05); there were no differences in pressure pain thresholds between MMPs and NCs for the left temporalis (P < 0.07) and right/left middle finger sites (P's > 0.93). These results are discussed in terms of the psychological and physiological processes that may account for the development of muscle pain in the masticatory system. (C) 1998 International Association for the Study of Pain. Published by Elsevier Science B.V. C1 Univ Kentucky, Dept Psychol, Lexington, KY 40506 USA. Univ Kentucky, Orofacial Pain Ctr, Lexington, KY 40506 USA. USN, Sch Dent, Natl Naval Med Ctr, Lexington, KY 40506 USA. RP Carlson, CR (reprint author), Univ Kentucky, Dept Psychol, 112 Kastle Hall, Lexington, KY 40506 USA. FU NIDCR NIH HHS [R03 DE10534-02] NR 73 TC 71 Z9 73 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3959 J9 PAIN JI Pain PD JUN PY 1998 VL 76 IS 3 BP 297 EP 307 DI 10.1016/S0304-3959(98)00063-3 PG 11 WC Anesthesiology; Clinical Neurology; Neurosciences SC Anesthesiology; Neurosciences & Neurology GA 105CK UT WOS:000075054700004 PM 9718248 ER PT J AU Cannon-Bowers, JA Rhodenizer, L Salas, E Bowers, CA AF Cannon-Bowers, JA Rhodenizer, L Salas, E Bowers, CA TI A framework for understanding pre-practice conditions and their impact on learning SO PERSONNEL PSYCHOLOGY LA English DT Article; Proceedings Paper CT 11th Annual Conference of the Society-for-Industrial-and-Organizational-Psychology CY APR-MAY -, 1996 CL SAN DIEGO, CA SP Soc Ind & Org Psychol ID INTRINSIC MOTIVATION; ADVANCE ORGANIZERS; ORIENTING ACTIVITIES; INTERACTIVE VIDEO; DECISION-MAKING; META-ANALYSIS; PERFORMANCE; ACHIEVEMENT; SKILL; ORIENTATION AB The purpose of this paper is to describe a framework for delineating those conditions that might affect the utility and effectiveness of practice in training. The framework includes factors that occur prior to, during, and after practice. Pre-practice conditions, such as attentional advice, advance organizers, goal orientation, and pre-training briefs, are designed to make the time spent in practice more efficient and useful. This paper first reviews the existing literature concerning the pre-practice conditions that have been identified. Next, a description of the underlying mechanisms for each pre-practice condition is suggested, and a set of propositions regarding these conditions is offered. Finally, past findings are summarized regarding pre-practice conditions and provide an agenda for future research. C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. Univ Cent Florida, Orlando, FL 32816 USA. RP USN, Air Warfare Ctr, Training Syst Div, Code 4961,12350 Res Pkwy, Orlando, FL 32826 USA. OI Cannon-Bowers, Janis/0000-0003-2154-4456 NR 59 TC 39 Z9 39 U1 0 U2 8 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0031-5826 EI 1744-6570 J9 PERS PSYCHOL JI Pers. Psychol. PD SUM PY 1998 VL 51 IS 2 BP 291 EP 320 DI 10.1111/j.1744-6570.1998.tb00727.x PG 30 WC Psychology, Applied; Management SC Psychology; Business & Economics GA ZW015 UT WOS:000074365100001 ER PT J AU Singh, DJ Mazin, II AF Singh, DJ Mazin, II TI Electronic structure, local moments, and transport in Fe2VAl SO PHYSICAL REVIEW B LA English DT Article ID ALLOYS AB Local spin density approximation calculations are used to elucidate electronic and magnetic properties of the Heusler structure Fe(2)VA1. The compound is found to be a low carrier density semimetal. The Fermi surface has small hole pockets derived from a triply degenerate Fe derived state at Gamma compensated by a V derived electron pocket at the X point. The ideal compound is found to be stable against ferromagnetism. Fe impurities on V sites, however, behave as local moments. Because of the separation of the hole and electron pockets the Ruderman-Kittel-Kasuya-Yosida interaction between such local moments should be rapidly oscillating on the scale of its decay, leading to the likelihood of spin-glass behavior for moderate concentrations of Fe on V sites. These features are discussed in relation to experimental observations of an unusual insulating state in this compound. C1 USN, Res Lab, Washington, DC 20375 USA. USN, Res Lab, Washington, DC 20375 USA. George Mason Univ, CSI, Fairfax, VA 22030 USA. RP USN, Res Lab, Code 6691, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008; Singh, David/I-2416-2012 NR 15 TC 127 Z9 127 U1 0 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JUN 1 PY 1998 VL 57 IS 22 BP 14352 EP 14356 DI 10.1103/PhysRevB.57.14352 PG 5 WC Physics, Condensed Matter SC Physics GA ZU948 UT WOS:000074252500061 ER PT J AU Luscombe, JH Luban, M AF Luscombe, JH Luban, M TI Simplified recursive algorithm for Wigner 3j and 6j symbols SO PHYSICAL REVIEW E LA English DT Article ID ANGULAR MOMENTA; 3J-COEFFICIENTS; 6J-COEFFICIENTS AB We present a highly accurate, ab initio recursive algorithm for evaluating the Wigner 3j and 6j symbols. Our method makes use of two-term, nonlinear recurrence relations that an obtained from the standard three-term recurrence relations satisfied by these quantities. The use of two-term recurrence relations eliminates the need for rescaling of iterates to control numerical overflows and thereby simplifies the widely used recursive algorithm of Schulten and Gordon. C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RP Luscombe, JH (reprint author), USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. NR 9 TC 16 Z9 16 U1 1 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 JUN PY 1998 VL 57 IS 6 BP 7274 EP 7277 DI 10.1103/PhysRevE.57.7274 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA ZU947 UT WOS:000074252400131 ER PT J AU Ngai, KL AF Ngai, KL TI Correlation between the secondary beta-relaxation time at T-g with the Kohlrausch exponent of the primary alpha relaxation or the fragility of glass-forming materials SO PHYSICAL REVIEW E LA English DT Article ID MOLECULAR-DYNAMICS SIMULATION; DIELECTRIC-SPECTROSCOPY; AMORPHOUS POLYMERS; NEUTRON-SCATTERING; PROPYLENE-GLYCOL; TRANSITION; LIQUIDS; MOTIONS; POLYBUTADIENE; METHACRYLATE) AB A strong correlation between the logarithm of the secondary beta-relaxation time, log(10)[tau(beta)(T-g)], and the Kohlrausch exponent, (l - n), or the fragility index m of the primary alpha-relaxation correlation function exp[-(t/tau(alpha))(1-n)], all at the glass transition temperature T-g, has been found in glass-forming materials in general. The beta relaxations considered are restricted to a class that merges or tends to merge with the alpha relaxations. For beta relaxations in polymeric glass formers that involve side groups, the class is further restricted to those that entail some motions of the polymer backbone. The correlation found indicates the existence of a connection between the beta and alpha relaxations. A possible origin of this connection is rationalized by the conceptual basis of the coupling model. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ngai, KL (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 50 TC 134 Z9 136 U1 2 U2 14 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 JUN PY 1998 VL 57 IS 6 BP 7346 EP 7349 DI 10.1103/PhysRevE.57.7346 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA ZU947 UT WOS:000074252400148 ER PT J AU Huba, JD Winske, D AF Huba, JD Winske, D TI Rayleigh-Taylor instability: Comparison of hybrid and nonideal magnetohydrodynamic simulations SO PHYSICS OF PLASMAS LA English DT Article ID MAGNETOTAIL BARIUM RELEASES; EXPANDING PLASMA CLOUDS; LARGE-LARMOR-RADIUS; HALL MAGNETOHYDRODYNAMICS; LIMIT; MODES AB The evolution of the Rayleigh-Taylor instability in a low beta, two-dimensional plasma is studied using a hybrid code and a;nonideal magnetohydrodynamic (MHD) code. The Rayleigh-Taylor instability was chosen as a test case because it is an important mixing process at boundary layers, and because it exhibits different behaviors in the conventional and nonideal limits. The nonideal MHD effects considered are the Hall term and finite Larmor radius (FLR) corrections. Three cases are considered in detail: conventional MHD, weak nonideal effects, and strong nonideal effects. In the conventional MHD regime the usual "bubble and spike" behavior of the Rayleigh-Taylor instability is observed. In the weak nonideal MHD regime long wavelength modes, reminiscent of the Kelvin-Helmholtz instability, dominate nonlinearly but very short wavelength filaments develop at the boundary interface. In the strong nonideal MHD regime, small-scale structures dominate and the boundary layer relaxes via a diffusion-like process rather than a large-scale nonlinear mixing process; In general, the hybrid and fluid simulations are in good agreement. The differences, both physical and numerical, are discussed. (C) 1998 American Institute of Physics. [S1070-664X(98)00906-9] C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. RP Huba, JD (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 27 TC 22 Z9 22 U1 2 U2 4 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 JUN PY 1998 VL 5 IS 6 BP 2305 EP 2316 DI 10.1063/1.872904 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 110KQ UT WOS:000075380300016 ER PT J AU Deeney, C Nash, TJ Spielman, RB Seaman, JF McGurn, JS Jobe, DO Vargas, MF Gilliland, TL Mock, RC Struve, KW Whitney, KG Pulsifer, PE Apruzese, JP Thornhill, JW Davis, J AF Deeney, C Nash, TJ Spielman, RB Seaman, JF McGurn, JS Jobe, DO Vargas, MF Gilliland, TL Mock, RC Struve, KW Whitney, KG Pulsifer, PE Apruzese, JP Thornhill, JW Davis, J TI Improved large diameter wire array implosions from increased wire array symmetry and on-axis mass participation SO PHYSICS OF PLASMAS LA English DT Article ID Z-PINCH IMPLOSIONS; K-SHELL EMISSION; X-RAY-EMISSION; OPTIMIZATION; PLASMAS AB Aluminum wire array, Z-pinch experiments have been performed on an 8 MA generator using arrays consisting of 24, 30, and 42 wires. These experiments were designed to scan through a region of (array mass, implosion velocity) space in which greater than 30% conversion of the implosion kinetic energy into K-shell x rays was predicted to occur [Thornhill et al., Phys. Plasmas 1, 321 (1994)]. Array masses between 120 and 2050 mu g/cm were used in these experiments. An analysis of the x-ray data taken using 24 wire arrays, shows a one-to-one correspondence between the observed kilo-electron-volt yields (5-64 kJ) and the fraction of initial array mass (0.3%-60%) that is radiating from the K shell. The 30 and 42 wire experiments demonstrated that tighter pinches with increased radiated powers were achieved with these larger wire number, improved symmetry arrays. In addition, increases in the implosion mass and array diameter in the 30 and 42 wire number cases resulted in increases in the radiated yield over the corresponding 24 wire shots, up to 88 kJ, which can be interpreted as due to improved coupling and thermalization of the kinetic energy. Moreover, spectroscopic analyses of the 30 and 42 wire experiments have shown that the increased wire numbers also resulted in K-shell radiating mass fractions of greater than 50%. (C) 1998 American Institute of Physics. [S1070-664X(98)03606-4] C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. USN, Res Lab, Washington, DC 20375 USA. RP Deeney, C (reprint author), Sandia Natl Labs, POB 5800,MS-1194, Albuquerque, NM 87185 USA. NR 22 TC 35 Z9 35 U1 0 U2 1 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 JUN PY 1998 VL 5 IS 6 BP 2431 EP 2441 DI 10.1063/1.872919 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 110KQ UT WOS:000075380300031 ER PT J AU Su, J Zhang, QM Wang, PC MacDiarmid, AG Wynne, KJ AF Su, J Zhang, QM Wang, PC MacDiarmid, AG Wynne, KJ TI Preparation and characterization of electrostrictive polyurethane films with conductive polymer electrodes SO POLYMERS FOR ADVANCED TECHNOLOGIES LA English DT Article DE polypyrrole; electrostrictive; polyurethane; dielectric properties; all-polymer composite films ID POLYPYRROLE; STABILITY AB All-polymer electrostrictive soft films were developed for the first time by depositing conductive polymer (polypyrrole) directly on both sides of solution-east electrostrictive polyurethane elastomer pms. The Fnal composite films are flexible with strong adhesion between the polyurethane film and the conductive polymer electrode. The conductivity (sheet resistivity similar to 1000 Ohm/ square), of the polymer electrode is appropriate for its intended use. The compatible interface between the polypyrrole electrode polymer and the electrostrictive polyurethane significantly improves the acoustic and optical transparency of these composite films, compared with using a metal electrode film. The all-polymer films also exhibit comparable dielectric properties to gold-electroded polyurethane pms in the temperature range from -40 degrees C to +80 degrees C. The temperature range covers the soft segment glass transition temperature of the polyurethane elastomers, which is about -20 degrees C. The films also show large electric field induced strain responses which are dependent on film thickness and measurement frequency. The electrostrictive characteristics in the all-polymer films show similarities to those of the films with gold electrodes under identical measurement conditions. (C) 1998 John Wiley & Sons, Ltd. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Univ Penn, Dept Chem, Philadelphia, PA 19104 USA. Off Naval Res, Arlington, VA 22217 USA. RP Su, J (reprint author), Allied Signal Inc, CRL-224, Morristown, NJ 07960 USA. NR 23 TC 46 Z9 46 U1 1 U2 8 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1042-7147 J9 POLYM ADVAN TECHNOL JI Polym. Adv. Technol. PD JUN PY 1998 VL 9 IS 6 BP 317 EP 321 DI 10.1002/(SICI)1099-1581(199806)9:6<317::AID-PAT758>3.3.CO;2-P PG 5 WC Polymer Science SC Polymer Science GA ZX145 UT WOS:000074483900001 ER PT J AU Price, GL AF Price, GL TI The entropy of rational powers shifts SO PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY LA English DT Article DE entropy; automorphisms; endomorphisms; factor; von Neumann algebras; noncommutative dynamical systems ID VONNEUMANN-ALGEBRAS; TYPE-II1 FACTORS AB The Connes-Stormer entropy of all rational Powers shifts is shown to be a 1/2 log 2. C1 USN Acad, Dept Math 9E, Annapolis, MD 21012 USA. RP Price, GL (reprint author), USN Acad, Dept Math 9E, Annapolis, MD 21012 USA. NR 12 TC 4 Z9 4 U1 0 U2 0 PU AMER MATHEMATICAL SOC PI PROVIDENCE PA 201 CHARLES ST, PROVIDENCE, RI 02940-2213 USA SN 0002-9939 J9 P AM MATH SOC JI Proc. Amer. Math. Soc. PD JUN PY 1998 VL 126 IS 6 BP 1715 EP 1720 DI 10.1090/S0002-9939-98-04304-4 PG 6 WC Mathematics, Applied; Mathematics SC Mathematics GA ZP832 UT WOS:000073792900017 ER PT J AU McCormick, GH AF McCormick, GH TI The revolutionary odyssey of Che Guevara SO QUEENS QUARTERLY LA English DT Article C1 USN, Postgrad Sch, Monterey, CA 93940 USA. RP McCormick, GH (reprint author), USN, Postgrad Sch, Monterey, CA 93940 USA. NR 17 TC 0 Z9 0 U1 1 U2 2 PU QUEENS QUARTERLY PI KINGSTON ONTARIO PA QUEENS UNIV, KINGSTON ONTARIO, OTTAWA K7L 3N6, CANADA SN 0033-6041 J9 QUEENS QUART JI Queens Q. PD SUM PY 1998 VL 105 IS 2 BP 169 EP 185 PG 17 WC Literary Reviews SC Literature GA 100TJ UT WOS:000074831200002 ER PT J AU Price, JL Guardala, NA Riel, GK Mathur, VK AF Price, JL Guardala, NA Riel, GK Mathur, VK TI Neutron response of a laser-heated thermoluminescence dosimetry system SO RADIATION MEASUREMENTS LA English DT Article; Proceedings Paper CT 3rd International Symposium on Luminescent Detectors and Transformers of Ionising Radiation (LUMDETR 97) CY OCT 06-10, 1997 CL USTRON, POLAND AB A laser-heated thermoluminescence dosimetry (LHTLD) system was-tested for albedo response to mono-energetic neutrons ranging in energy from 200 keV to 2.8 MeV. For neutron response measurements, pairs of magnesium borate ((MgB4O7)-B-10/11:Tm) and lithium fluoride ((LiF)-Li-6/7:Mg,Ti) phosphor chips were used. In general, the LHTLD system based on (MgB4O7)-B-10/11:Tm shows response similar to the LiF system, that is a decreasing response ratio (R = dose read/dose applied) with increasing neutron energy approaching a response of 0.07 for higher energies. In addition, the neutron responses consistently indicates a higher response for the LiF system than the LHTLD system by about 22%, possibly due in part to the internal shielding of non-albedo thermal neutrons in the LHTLD badge. Published by Elsevier Science Ltd. C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. RP Price, JL (reprint author), USN, Ctr Surface Warfare, Carderock Div, Code 682, W Bethesda, MD 20817 USA. NR 7 TC 2 Z9 2 U1 2 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1350-4487 J9 RADIAT MEAS JI Radiat. Meas. PD JUN-AUG PY 1998 VL 29 IS 3-4 BP 379 EP 382 DI 10.1016/S1350-4487(98)00051-1 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 105FY UT WOS:000075063100031 ER PT J AU Boyer, CN Holland, GE Seely, JF AF Boyer, CN Holland, GE Seely, JF TI Portable hard x-ray source for nondestructive testing and medical imaging SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB A portable hard x-ray source has been developed for nondestructive testing, medical imaging, and flash x-ray radiography. The source is powered by a Marx generator that produces a 200 kV, 1.2 kA pulse of 60 ns full width at half maximum. The x-ray tube is composed of a tungsten anode and a mesh cathode. The time dependence of the voltage, current, and x-ray emission were measured and were in good agreement with computer simulations. The simulation model accounted for the 15 capacitors and 15 spark gap switches of the Marx generator and the perveance of the electron flow across the anode-cathode gap. The simulations indicated that the 5 J energy that was stored in the Marx generator was efficiently delivered to the x-ray tube. The measured x-ray exposure, 34 mR at a distance of 30 cm, was in good agreement with the calculated exposure. X-ray images are presented that demonstrate the capabilities of the x-ray source for medical imaging, nondestructive testing, and flash x-ray radiography. [S0034-6748(98)04906-5] C1 Univ Space Res Assoc, Washington, DC 20024 USA. Sachs Freeman Associates Inc, Landover, MD 20785 USA. USN, Res Lab, Washington, DC 20375 USA. RP Boyer, CN (reprint author), Univ Space Res Assoc, Washington, DC 20024 USA. NR 11 TC 18 Z9 20 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JUN PY 1998 VL 69 IS 6 BP 2524 EP 2530 DI 10.1063/1.1148953 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 108RK UT WOS:000075279100047 ER PT J AU Wagstaff, MD Meredith, RW AF Wagstaff, MD Meredith, RW TI UAIM - Multibeam high-frequency sonar simulation SO SEA TECHNOLOGY LA English DT Article C1 Planning Syst Inc, Slidell, LA USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Wagstaff, MD (reprint author), Planning Syst Inc, Slidell, LA 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 JUN PY 1998 VL 39 IS 6 BP 83 EP 86 PG 4 WC Engineering, Ocean SC Engineering GA ZW002 UT WOS:000074363700014 ER PT J AU Carroll, RG Riley, JL Levine, BL Blair, PJ St Louis, DC June, CH AF Carroll, RG Riley, JL Levine, BL Blair, PJ St Louis, DC June, CH TI The role of co-stimulation in regulation of chemokine receptor expression and HIV-1 infection in primary T lymphocytes SO SEMINARS IN IMMUNOLOGY LA English DT Review DE chemokines; CCR5; CD28; CTLA-4; HIV-1 ID CD28 SIGNAL-TRANSDUCTION; PEPTIDE-MHC COMPLEXES; VIRUS-REPLICATION; FUSION COFACTOR; CELL ACTIVATION; CD4(+) CELLS; LOW-AFFINITY; IN-VITRO; COSTIMULATION; RANTES AB Fusion and entry of the human immunodeficiency virus (HN) into CD4(+) T lymphocytes requires expression of CD4 and a coreceptor. At least eight chemokine receptors can serve as coreceptors for HIV. Accumulating evidence indicates that multiple factors, including the state of cellular differentiation and activation, regulate the expression of alpha- and beta-chemokine receptors on lymphocytes. For example, binding of antibodies to the CD28 coreceptor can downregulate expression of beta-chemokine receptors, and this appears to have important consequences on the susceptibility of CD4(+) T lymphocytes to infection by HIV. In contrast, binding of the natural CD28 ligand B7 or antibodies to the CD28 homologue CTLA-4 can upregulate CCR5 expression, suggesting a reciprocal interaction between CD28 and CTLA-4 and the regulation of beta-chemokine receptor expression. Thus, the CD28/ CTLA-4/B7 co-stimulation pathway is identified as a potential novel target for the control of susceptibility to some strains of HIV-1 infection. C1 Henry M Jackson Fdn, Mil HIV Res Program, Bethesda, MD 20889 USA. Walter Reed Army Inst Res, Rockville, MD 20850 USA. USN, Med Res Inst, Bethesda, MD 20889 USA. RP Carroll, RG (reprint author), Henry M Jackson Fdn, Mil HIV Res Program, Bethesda, MD 20889 USA. RI Levine, Bruce/D-1688-2009; OI Riley, James/0000-0002-1057-576X NR 50 TC 17 Z9 18 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 1044-5323 J9 SEMIN IMMUNOL JI Semin. Immunol. PD JUN PY 1998 VL 10 IS 3 BP 195 EP 202 DI 10.1006/smim.1998.0131 PG 8 WC Immunology SC Immunology GA 131NG UT WOS:000076581700005 PM 9653046 ER PT J AU Whiteford, M Spirig, A Rudolph, A Neville, L Abdullah, F Feuerstein, G Rabinovici, R AF Whiteford, M Spirig, A Rudolph, A Neville, L Abdullah, F Feuerstein, G Rabinovici, R TI Effect of liposome-encapsulated hemoglobin on the development of endotoxin-induced shock in the rat SO SHOCK LA English DT Article ID TUMOR-NECROSIS-FACTOR; BACTERIAL LIPOPOLYSACCHARIDE; BIOLOGICAL RESPONSES; BLOOD SUBSTITUTE; STORAGE; INJURY; FLUID AB Liposome-encapsulated hemoglobin (LEI-I) is an experimental oxygen-carrying resuscitation fluid. Because LEH is cleared from the circulation primarily by the reticuloendothelial system, its effect on the development of sepsis remains a major concern. Thus, the present study aimed to evaluate whether LEH modifies consequences of endotoxemia in the conscious normovolemic rat, LEH infusion at 10% of estimated blood volume (n = 10) did not affect mortality (30%, p < .05) and serum tumor necrosis factor-alpha levels (6204 +/- 414, p < .05) induced by 3.6 mg/kg Escherichia coli endotoxin administered (intravenous bolus) 22 h later. in contrast, when a shorter LEH-endotoxin time interval (< 12 h, n = 10) or a higher dose of endotoxin (14.4 mg/kg, n = 20) was tested, LEH enhanced endotoxin-induced mortality (90% and 100%, respectively, p < .05) and broadened serum tumor necrosis factor-alpha response without modifying its peak levels. LEH (n = 20) did not exacerbate the endotoxin-induced tachycardia, leukopenia, and thrombocytopenia. Therefore, in this model, the effect of LEH on endotoxin-induced responses was dependent on the time interval between LEH and endotoxin administration as well as the endotoxin dose. The clinical relevance of these results should be further investigated. C1 Thomas Jefferson Univ, Jefferson Med Coll, Dept Surg, Philadelphia, PA 19107 USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. SmithKline Beecham Pharmaceut, Dept Cardiovasc Pharmacol, King Of Prussia, PA 19406 USA. RP Rabinovici, R (reprint author), Yale Univ, Sch Med, Sect Trauma & Surg Crit Care, Dept Surg, 333 Cedar St,LH 118, New Haven, CT 06520 USA. NR 29 TC 8 Z9 8 U1 0 U2 0 PU BIOMEDICAL PRESS PI AUGUSTA PA 1021 15TH ST, BIOTECH PARK STE 9,, AUGUSTA, GA 30901 USA SN 1073-2322 J9 SHOCK JI Shock PD JUN PY 1998 VL 9 IS 6 BP 428 EP 433 DI 10.1097/00024382-199806000-00007 PG 6 WC Critical Care Medicine; Hematology; Surgery; Peripheral Vascular Disease SC General & Internal Medicine; Hematology; Surgery; Cardiovascular System & Cardiology GA ZU053 UT WOS:000074156500007 PM 9645495 ER PT J AU Koomen, MJ Howard, RA Michels, DJ AF Koomen, MJ Howard, RA Michels, DJ TI The shape of the outer corona during cycle 21 SO SOLAR PHYSICS LA English DT Article ID HELIOSPHERIC CURRENT SHEET; SOLAR CORONA; MAGNETIC-FIELD AB The Naval Research Laboratory (NRL) Solwind coronagraph recorded the outer corona at elongations 2.5 R-. to 10 R-. during the 6 1/2-year interval from March 1979, before solar maximum, to the beginning of solar minimum in September 1985. During the minimum period, when the solar magnetic field was dipole-like, the observed corona consisted of the equatorial streamer belt that is characteristic of solar minimum, and that is interpreted as an edgewise view of a nearly flat current sheet or coronal disk lying near the plane of the heliographic equator. The observed disk was a radial projection from the magnetic neutral line that was computed for the 2.5 R-. source surface surrounding the Sun. At earlier times, shortly after solar maximum, the observed corona often consisted of a single coronal disk similar to that at solar minimum, but strongly tilted to the heliographic equator. Again this disk projected from a tilted magnetic neutral line that was computed for the 2.5 R-. source surface. Solar rotation allowed this coronal disk to be viewed in all aspects. In the edgewise view it appeared as a tilted streamer belt. In the broadside view the more flower-like pattern of solar maximum was observed. The latter view was interpreted as a non-uniform distribution of coronal material in the thin coronal disk. There were many intervals during the declining phase of the solar cycle when the computed magnetic neutral line at 2.5 R-. remained relatively simple but was not the source of an observable coronal disk. This latter result was probably because of the limitations of plane-of-sky observations, combined with short-term changes in the corona. Altogether, a single coronal disk, either flat or somewhat convoluted, was recognizable during only one third of the 6 1/2 year lifetime of the coronagraph. C1 SFA Inc, Largo, MD 20772 USA. USN, Res Lab, Washington, DC 20375 USA. RP Koomen, MJ (reprint author), SFA Inc, Largo, MD 20772 USA. NR 14 TC 7 Z9 7 U1 0 U2 0 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 JUN PY 1998 VL 180 IS 1-2 BP 247 EP 263 DI 10.1023/A:1005039609265 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 103CK UT WOS:000074963700015 ER PT J AU Hayes, SM Taylor, HA McGowan, LM AF Hayes, SM Taylor, HA McGowan, LM TI Maternity care practices of navy family practice residency graduates after leaving the military SO SOUTHERN MEDICAL JOURNAL LA English DT Article ID OBSTETRICS AB Background. Nationwide, 32% of residency-trained family physicians deliver babies compared with 73% to 90% in the military. This study describes and defines issues that could ultimately help revive family practice maternity care. Method, We surveyed 112 family physicians who had left the navy Results. Ninety-one percent had delivered babies in the navy, 45% since leaving the military and 25% currently. Principal maternity care incentives both in and out of the military were personal and professional satisfaction. Reasons for not providing civilian maternity care included malpractice risks, insurance costs, and lifestyle issues. The decision for providing maternity care was usually made before or during residency whereas the decision against was most often made upon leaving the military Among more recent graduates (1990-1995), 48% continued to deliver babies in civilian practice. (This is about 20% more than recent civilian graduates.) Malpractice concerns were less important to this group than to earlier graduates. Conclusions. Factors discouraging family physicians from providing maternity care arise from their practice environment and are not easily overcome with improved training and experience. Recent navy residency graduates are not as easily discouraged. C1 USN Hosp, Dept Family Practice, Jacksonville, FL USA. RP Hayes, SM (reprint author), USNH, USNR, PSC 475,Box 1544, FPO, AP 96350 USA. NR 18 TC 0 Z9 0 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 JUN PY 1998 VL 91 IS 6 BP 555 EP 559 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA ZT601 UT WOS:000074104200009 PM 9634118 ER PT J AU Valeri, CR Crowley, JP Loscalzo, J AF Valeri, CR Crowley, JP Loscalzo, J TI The red cell transfusion trigger: has a sin of commission now become a sin of omission? SO TRANSFUSION LA English DT Review ID RECOMBINANT-HUMAN-ERYTHROPOIETIN; NEAR-INFRARED SPECTROSCOPY; BLEEDING-TIME; BLOOD-CELLS; PLATELET-FUNCTION; NITRIC-OXIDE; RELAXING FACTOR; HEMODIALYSIS-PATIENTS; NONCARDIAC SURGERY; THROMBUS FORMATION C1 Boston Univ, Sch Med, USN, Blood Res Lab, Boston, MA 02118 USA. Boston Univ, Sch Med, Evans Dept Med, Boston, MA 02118 USA. Boston Med Ctr, Evans Dept Med, Boston, MA USA. Boston Med Ctr, Whitaker Cardiovasc Inst, Boston, MA USA. Brown Univ, Sch Med, Rhode Isl Hosp, Dept Med, Providence, RI 02912 USA. RP Valeri, CR (reprint author), Boston Univ, Sch Med, USN, Blood Res Lab, 615 Albany St, Boston, MA 02118 USA. NR 100 TC 53 Z9 53 U1 0 U2 2 PU AMER ASSOC BLOOD BANKS PI BETHESDA PA 8101 GLENBROOK RD, BETHESDA, MD 20814-2749 USA SN 0041-1132 J9 TRANSFUSION JI Transfusion PD JUN PY 1998 VL 38 IS 6 BP 602 EP 610 DI 10.1046/j.1537-2995.1998.38698326341.x PG 9 WC Hematology SC Hematology GA ZX852 UT WOS:000074561900012 PM 9661695 ER PT J AU Feitler, JN Corsi, TM Grimm, CM AF Feitler, JN Corsi, TM Grimm, CM TI Strategic and performance changes among LTL motor carriers: 1976-1993 SO TRANSPORTATION JOURNAL LA English DT Article C1 USN, Postgrad Sch, Monterey, CA 93943 USA. Univ Maryland, College Pk, MD 20742 USA. RP Feitler, JN (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 16 TC 4 Z9 5 U1 0 U2 0 PU AMER SOC TRANSPORTATION LOGISTICS, INC PI LOCK HAVEN PA 216 E CHURCH ST, LOCK HAVEN, PA 17745 USA SN 0041-1612 J9 TRANSPORT J JI Transp. J. PD SUM PY 1998 VL 37 IS 4 BP 5 EP 12 PG 8 WC Management; Transportation SC Business & Economics; Transportation GA 113QV UT WOS:000075563500001 ER PT J AU Looney, RE Frederiksen, PC AF Looney, RE Frederiksen, PC TI Rail track expansion in developing countries in the 1980s SO TRANSPORTATION RESEARCH PART E-LOGISTICS AND TRANSPORTATION REVIEW LA English DT Article DE rail track expansion; developing countries AB Per capita income, country size, and economic growth are often seen as being major determinants of rail track expansion in developing countries. However, we could not empirically verify these explanations for rail expansion using recent World Bank data for a set of 35 developing countries. Instead, a factor analysis suggested multilateral loans to have been important. A discriminant analysis indicated only four variables are needed to predict a country's correct grouping into either a high and low rail expansion group. Regression analysis indicates that 1970s investment offset 1980s investment for the entire sample and the high expansion group. For the low expansion group, a factor capturing the quality of life appears to be the most important predictor of rail investment. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Def Resources Management Inst, Monterey, CA 93943 USA. USN, Postgrad Sch, Dept Natl Secur Affairs, Monterey, CA 93943 USA. RP Frederiksen, PC (reprint author), USN, Postgrad Sch, Def Resources Management Inst, Code 64, Monterey, CA 93943 USA. NR 7 TC 0 Z9 0 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1366-5545 J9 TRANSPORT RES E-LOG JI Transp. Res. Pt. e-Logist. Transp. Rev. PD JUN PY 1998 VL 34 IS 2 BP 131 EP 136 DI 10.1016/S1366-5545(98)00003-9 PG 6 WC Economics; Engineering, Civil; Operations Research & Management Science; Transportation; Transportation Science & Technology SC Business & Economics; Engineering; Operations Research & Management Science; Transportation GA 125CW UT WOS:000076220700004 ER PT J AU Buttolph, TB Dick, EJ Toner, CB Broome, JR Williams, R Kang, YH Wilt, NL AF Buttolph, TB Dick, EJ Toner, CB Broome, JR Williams, R Kang, YH Wilt, NL TI Cutaneous lesions in swine after decompression: histopathology and ultrastructure SO UNDERSEA & HYPERBARIC MEDICINE LA English DT Article DE animal model; cutaneous lesions; decompression sickness; pathology; swine; skin; animal; veterinary; pig ID SICKNESS; INVOLVEMENT; VASCULITIS; COMPLEMENT; FLOW AB A detailed histopathologic description of skin lesions from a porcine model of decompression sickness (DCS) is presented. Pigs were dived in a dry chamber on a variety of profiles over an 11-mo period, with a 0.1 - 0.6 (10-60%) incidence of cutaneous lesions. The clinical appearance of the lesions evolved from irregular, sharply demarcated areas of erythema to violaceous and, eventually, darkly mottled macules. The lesions were biopsied under deep, sedative anesthesia. Histologic abnormalities were found in 91% (20/22) of the biopsies from clinically apparent cutaneous lesions. Vascular congestion was the most common finding. Focal areas of vasculitis were noted in 45% (10/22) of the lesions. Perivascular neutrophil infiltrates, edema, and, occasionally, hemorrhage were also noted. Ultrastructural abnormalities were found in all of the lesions studied. Acute inflammation affecting the dermal vasculature was the most common finding. Platelets were rarely observed aggregating within vessels. The clinical and histologic features of cutaneous lesions in pigs after decompression are compared with previous accounts in humans. The model provides a useful tool for the study of cutaneous lesions in DCS and may be a means of exploring interventions in the disease. C1 USN, Med Res Inst, Bethesda, MD 20889 USA. RP Buttolph, TB (reprint author), USN, Med Res Inst, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 23 TC 18 Z9 19 U1 0 U2 0 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 SUM PY 1998 VL 25 IS 2 BP 115 EP 121 PG 7 WC Marine & Freshwater Biology; Medicine, Research & Experimental SC Marine & Freshwater Biology; Research & Experimental Medicine GA ZZ312 UT WOS:000074716800007 PM 9670437 ER PT J AU Layne, C AF Layne, C TI Rethinking American grand strategy - Hegemony or balance of power in the twenty-first century? SO WORLD POLICY JOURNAL LA English DT Article ID EUROPE; NATO RP Layne, C (reprint author), USN, Postgrad Sch, Monterey, CA 93940 USA. NR 47 TC 8 Z9 8 U1 1 U2 5 PU WORLD POLICY INST PI NEW YORK PA NEW SCHOOL SOCIAL RESEARCH 65 FIFTH AVE, STE 413, NEW YORK, NY 10003 USA SN 0740-2775 J9 WORLD POLICY J JI World Policy J. PD SUM PY 1998 VL 15 IS 2 BP 8 EP 28 PG 21 WC International Relations SC International Relations GA ZV882 UT WOS:000074351200002 ER PT J AU Jenn, DC Pace, PE Hatziathanasiou, T Vitale, R AF Jenn, DC Pace, PE Hatziathanasiou, T Vitale, R TI High resolution wideband direction finding arrays based on optimum symmetrical number system encoding SO ELECTRONICS LETTERS LA English DT Article ID ANALOG AB A new interferometer direction finding (DF) array architecture based on thr optimum symmetrical number system (OSNS) is presented. OSNS arrays are capable of unambiguous high resolution DF: over a wide bandwidth and field of view with as few as three elements, with multiple baseline options. A three-element array was designed, Fabricated and tested at 8,5 GHz to verify the OSNS concepts experimentally. C1 USN, Postgrad Sch, Ctr Joint Serv Elect Warfare, Monterey, CA 93943 USA. RP Jenn, DC (reprint author), USN, Postgrad Sch, Ctr Joint Serv Elect Warfare, Monterey, CA 93943 USA. NR 8 TC 4 Z9 4 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 MAY 28 PY 1998 VL 34 IS 11 BP 1062 EP 1064 DI 10.1049/el:19980811 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA ZW070 UT WOS:000074370900020 ER PT J AU Bacmeister, JT Siskind, DE Summers, ME Eckermann, SD AF Bacmeister, JT Siskind, DE Summers, ME Eckermann, SD TI Age of air in a zonally averaged two-dimensional model SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID LOWER STRATOSPHERE; CARBON-DIOXIDE; ATMOSPHERIC TRANSPORT; RESIDUAL CIRCULATION; NUMERICAL ADVECTION; MIDDLE ATMOSPHERE; DOWNWARD CONTROL; ANNUAL CYCLE; WATER-VAPOR; TROPOSPHERE AB The distribution of age-of-air in a two-dimensional, zonally averaged model of the atmosphere is examined. The age-of-air is determined from mixing ratios of a fictitious tracer with a linearly increasing tropospheric source. The impact of horizontal mixing is isolated by performing parallel calculations with and without horizontal mixing terms in the tracer evolution equation. We examine the evolution of the tracer over several model years, using different tropical heat sources as well as different amounts of planetary wave mixing and drag. Typical ages in the midstratosphere when horizontal mixing is included range from 3 to over 5 years, depending primarily on the strength of the model's :prescribed tropical heat source. These values of age are within the range of observational estimates based on long-lived tracers with increasing tropospheric mixing ratios, such as HF, CO2 and SF6. Age determined from the horizontally unmixed tracer is reduced by 1 to 2 years. However, the evolution of the unmixed tracer is consistent with observed behavior of tropical water vapor oscillations in data from the HAlogen Occultation Experiment (HALOE). We found stronger than expected sensitivity of middle atmospheric age to prescribed heating in the tropical troposphere. This sensitivity in our model arises from small resulting changes to the residual vertical velocity in the tropics. These vertical velocity changes are in turn associated with net heating changes of 0.05-0.10 K d(-1) in the tropical lower stratosphere. We argue that changes of this magnitude are within the uncertainties imposed by natural variations in the tropics. C1 USN, Res Lab, Washington, DC 20375 USA. Computat Phys Inc, Fairfax, VA 22031 USA. RP Bacmeister, JT (reprint author), USN, Res Lab, Code 7641, Washington, DC 20375 USA. EM julio@ismap5.nrl.navy.mil NR 46 TC 17 Z9 17 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 MAY 27 PY 1998 VL 103 IS D10 BP 11263 EP 11288 DI 10.1029/98JD00277 PG 26 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZP485 UT WOS:000073758200009 ER PT J AU Thompson, PE Silvestre, C Twigg, M Jernigan, G Simons, DS AF Thompson, PE Silvestre, C Twigg, M Jernigan, G Simons, DS TI Atomic hydrogen for the formation of abrupt Sb doping profiles in MBE-grown Si SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 7th International Symposium on Silicon Molecular Beam Epitaxy CY JUL 13-17, 1997 CL BANFF, CANADA SP SiGe Microsyst Inc, Natl Res Council Canada, Inst Microstruct Sci, VG Semicon, Super Vacuum Technol, Instruments SA Inc DE molecular beam epitaxy; atomic hydrogen; surfactant-assisted growth; silicon; antimony; secondary ion mass spectrometry ID MOLECULAR-BEAM EPITAXY; GE SURFACE SEGREGATION; LOW-TEMPERATURE; SI(100); IRRADIATION; DESORPTION; SILICON AB Previously, atomic hydrogen has been shown to be effective in reducing the segregation of Ge on Si(100) during solid source molecular beam epitaxy growth. In this work we have investigated atomic hydrogen to determine if it is equally effective in reducing the segregation of Sb on Si(100). Using secondary ion mass spectrometry, we demonstrated that the co-deposition of atomic hydrogen during Sb doping of Si at 500 degrees C reduced the surface segregation ratio by greater than two orders of magnitude. However, if atomic hydrogen was applied for more than 20 nm of growth, extended defects were formed. In addition, the as-grown Sb-doped layers had a low percentage of electrical activation as measured by capacitance-voltage profiling. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. NIST, Gaithersburg, MD 20899 USA. RP USN, Res Lab, Code 6812, Washington, DC 20375 USA. EM thompson@estd.nrl.navy.mil NR 20 TC 6 Z9 6 U1 1 U2 3 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 MAY 26 PY 1998 VL 321 BP 120 EP 124 DI 10.1016/S0040-6090(98)00459-3 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA ZZ593 UT WOS:000074745700023 ER PT J AU Vodopyanov, KL O'Neill, K Serapiglia, GB Phillips, CC Hopkinson, M Vurgaftman, I Meyer, JR AF Vodopyanov, KL O'Neill, K Serapiglia, GB Phillips, CC Hopkinson, M Vurgaftman, I Meyer, JR TI Phase-matched second harmonic generation in asymmetric double quantum wells SO APPLIED PHYSICS LETTERS LA English DT Article ID 2ND-HARMONIC GENERATION; INTERSUBBAND-TRANSITION; MU-M AB Efficient (similar to 1%) second harmonic generation, resonantly enhanced near lambda=8.6 mu m, has been observed in asymmetric double multi-quantum well structures. We used (i) edge-emitting waveguide geometry where the phase matching was achieved by incorporating a separate multiple quantum well region which modifies (via the Kramers-Kronig relation) the dispersion of light and (ii) 45 degrees wedge multi-bounce geometry where the phases of second harmonic waves generated at sequential bounces were synchronized by changing the angle of incidence. (C) 1998 American Institute of Physics. C1 Univ London Imperial Coll Sci Technol & Med, Dept Phys, Solid State Grp, London SW7 2BZ, England. Univ Sheffield, Dept Elect & Elect Engn, Sheffield S1 3JD, S Yorkshire, England. USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Vodopyanov, KL (reprint author), Univ London Imperial Coll Sci Technol & Med, Dept Phys, Solid State Grp, London SW7 2BZ, England. RI Hopkinson, Mark/H-8239-2012; OI Hopkinson, Mark/0000-0002-8097-6913 NR 13 TC 23 Z9 23 U1 0 U2 7 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 MAY 25 PY 1998 VL 72 IS 21 BP 2654 EP 2656 DI 10.1063/1.121088 PG 3 WC Physics, Applied SC Physics GA 108NZ UT WOS:000075273500009 ER PT J AU Rabinovich, W AF Rabinovich, W TI Spatial light modulators - Introduction SO OPTICS EXPRESS LA English DT Editorial Material C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Rabinovich, W (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 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 MAY 25 PY 1998 VL 2 IS 11 BP 431 EP 431 PG 1 WC Optics SC Optics GA 130XZ UT WOS:000076546800001 PM 19381211 ER PT J AU Rabinovich, WS Bashkansky, M Bowman, SR Mahon, R Battle, PR AF Rabinovich, WS Bashkansky, M Bowman, SR Mahon, R Battle, PR TI Speckle photography using optically addressed multiple quantum well spatial light modulators SO OPTICS EXPRESS LA English DT Article ID PARTICLE-IMAGE-VELOCIMETRY; INTERFEROMETRY; FRINGES AB We demonstrate speckle photography using an optically addressed multiple quantum well spatial light modulator. An optical Fourier transform is used to allow real-time displacement measurements. (C) 1998 Optical Society of America. C1 USN, Res Lab, Washington, DC 20375 USA. Jaycor, Mclean, VA 22102 USA. USN Acad, Dept Phys, Annapolis, MD 21401 USA. RP Rabinovich, WS (reprint author), USN, Res Lab, Code 5642, Washington, DC 20375 USA. NR 13 TC 6 Z9 6 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 MAY 25 PY 1998 VL 2 IS 11 BP 449 EP 453 PG 5 WC Optics SC Optics GA 130XZ UT WOS:000076546800004 PM 19381214 ER PT J AU Moriarty, RM Enache, LA Gilardi, R Gould, GL Wink, DJ AF Moriarty, RM Enache, LA Gilardi, R Gould, GL Wink, DJ TI Michael addition to alpha,beta-unsaturated arene ruthenium(II) cyclopentadiene complexes: endo nucleophilic addition SO CHEMICAL COMMUNICATIONS LA English DT Article ID DISPLACEMENT-REACTIONS; ORGANIC-SYNTHESIS; METAL COMPLEXES; HEXAFLUOROPHOSPHATES; FUNCTIONALIZATION AB Certain carbon and sulfur nucleophiles add to the beta-terminus of the styrene system in alpha,beta-unsaturated arene ruthenium(II) cyclopentadiene complexes, and unexpected endo addition occurs preferentially in some cases. C1 Univ Illinois, Dept Chem, Chicago, IL 60607 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Moriarty, RM (reprint author), Univ Illinois, Dept Chem, Chicago, IL 60607 USA. EM moriarty@uic.edu NR 25 TC 10 Z9 10 U1 0 U2 3 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE CB4 4WF, CAMBS, ENGLAND SN 1359-7345 J9 CHEM COMMUN JI Chem. Commun. PD MAY 21 PY 1998 IS 10 BP 1155 EP 1156 DI 10.1039/a707386k PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA ZP537 UT WOS:000073763400048 ER PT J AU Kozikowski, AP Araldi, GL Boja, J Meil, WM Johnson, KM Flippen-Anderson, JL George, C Saiah, E AF Kozikowski, AP Araldi, GL Boja, J Meil, WM Johnson, KM Flippen-Anderson, JL George, C Saiah, E TI Chemistry and pharmacology of the piperidine-based analogues of cocaine. Identification of potent DAT inhibitors lacking the tropane skeleton SO JOURNAL OF MEDICINAL CHEMISTRY LA English DT Article ID DOPAMINE TRANSPORTER; BINDING-SITES; SUBSTRATE; ESTERS AB To discover agents that might be useful in the treatment of cocaine abuse, we have chosen to re-explore a class of molecules that was first reported by Clarke et al. in 1973 and that was and shown to lack locomotor stimulatory activity in mice. These compounds are piperidine-3-carboxylic acid esters bearing a 4-chlorophenyl group in position 4, and as such, these structures may be viewed as truncated versions of the WIN series compounds, i.e., they lack the two-carbon bridge of the tropanes. All members of this class were synthesized starting from arecoline hydrobromide and obtained in optically pure form through resolution methods using either (+)- or (-)-dibenzoyltartaric acid. Interestingly, we have found that these piperidines do, in fact, exhibit substantial affinity in both WIN 35,428 binding at the dopamine transporter and in the inhibition of [H-3]dopamine uptake. Of all of the compounds synthesized, the 3-n-propyl derivative (-)-9 was found to be the most potent with a binding affinity of 3 nM. This simple piperidine is thus 33-fold more potent than cocaine in binding affinity and 29-fold more potent in its inhibition of dopamine uptake. Although no efforts have presently been made to "optimize" binding affinity at the DAT, the substantive activity found for the n-propyl derivative (-)-9 is remarkable; the compound is only about 10-fold less active than the best of the high-affinity tropanes of the WIN series. As a further point of interest, it was found that the cis-disubstituted piperidine (-)-3 is only about 2-fold more potent than its trans isomer (+)-11. This result stands in sharp contrast to the data reported for the tropane series, for the epimerization of the substituent at C-2 from beta to alpha has been reported to result in a lowering of activity by 30-200-fold. This smaller spread in binding affinities for the piperidines may reflect the smaller size of these molecules relative to the tropanes, which allows both the cis and the trans isomers to adjust themselves to the binding site on the DAT. Our present demonstration that these piperidine structures do, in fact, possess significant DAT activity, taken together with their reported lack of locomotor activity, provides a compelling argument for exploring this class of molecules further in animal behavioral experiments. The present work thus broadens the scope of structures that may be considered as lead structures in the search for cocaine abuse medications. C1 Georgetown Univ, Med Ctr, Inst Cognit & Computat Sci, Drug Discovery Program, Washington, DC 20007 USA. NE Ohio Univ, Coll Med, Dept Pharmacol, Rootstown, OH 44272 USA. Univ Texas, Med Branch, Dept Pharmacol & Toxicol, Galveston, TX 77555 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. Helios Pharmaceut, Louisville, KY 40299 USA. RP Kozikowski, AP (reprint author), Georgetown Univ, Med Ctr, Inst Cognit & Computat Sci, Drug Discovery Program, 3970 Reservoir Rd NW, Washington, DC 20007 USA. RI Johnson, Kenneth/E-7944-2014 FU NIDA NIH HHS [DA11546] NR 20 TC 71 Z9 71 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-2623 J9 J MED CHEM JI J. Med. Chem. PD MAY 21 PY 1998 VL 41 IS 11 BP 1962 EP 1969 DI 10.1021/jm980028+ PG 8 WC Chemistry, Medicinal SC Pharmacology & Pharmacy GA ZQ620 UT WOS:000073886300022 PM 9599245 ER PT J AU White, CT Todorov, TN AF White, CT Todorov, TN TI Carbon nanotubes as long ballistic conductors SO NATURE LA English DT Article ID TUBULES; WIRES AB Early theoretical work on single-walled carbon nanotubes(1-3) predicted that a special achiral subset of these structures known as armchair nanotubes(3) should be metallic. Tans et al.(4) have recently confirmed these predictions experimentally and also showed directly that coherent electron transport can be maintained through these nanowires up to distances of at least 140 nm. But single-walled armchair nanotubes are one-dimensional conductors with only two open conduction channels (energy subbands in a laterally confined system that cross the Fermi level)(1-3). Hence, with increasing length, their conduction electrons ultimately become localize(5) owing to residual disorder in the tube which is inevitably produced by interactions between the tube and its environment. We present here calculations which show, however, that unlike normal metallic wires, conduction electrons in armchair nanotubes experience an effective disorder averaged over the tube's circumference, leading to electron mean free paths that increase with nanotube diameter. This increase should result in exceptional ballistic transport properties and localization lengths of 10 mu m or more for tubes with the diameters that are typically produced experimentally(6). C1 USN, Res Lab, Washington, DC 20375 USA. Univ Oxford, Dept Mat, Oxford OX1 3PH, England. RP White, CT (reprint author), USN, Res Lab, Code 6179, Washington, DC 20375 USA. NR 14 TC 577 Z9 583 U1 14 U2 105 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD MAY 21 PY 1998 VL 393 IS 6682 BP 240 EP 242 DI 10.1038/30420 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZP513 UT WOS:000073761000044 ER PT J AU Pinto, JF Esterowitz, L AF Pinto, JF Esterowitz, L TI Unstable Cr : LiSAF laser resonator with a variable reflectivity output coupler SO APPLIED OPTICS LA English DT Article ID SUPER-GAUSSIAN MIRRORS AB The performance of a flash-lamp-pumped Cr:LiSAF unstable laser resonator utilizing a fourth-order super-Gaussian variable reflectivity mirror as an output coupler is described. The super-Gaussian mirror results in a smooth, flattop transverse beam profile in the near field that is advantageous for nonlinear frequency-conversion applications, Long-pulse and Q-switched operation of the Cr:LiSAF unstable laser resonator are described and compared with stable resonator operation. We obtained tunable ultraviolet radiation extending from 267 to 290 nm by frequency mixing the Q-switched CrLiSAF laser output with lithium triborate and beta-barium berate nonlinear crystals. C1 USN, Res Lab, Washington, DC 20375 USA. RP Pinto, JF (reprint author), USN, Res Lab, Code 5641, Washington, DC 20375 USA. NR 12 TC 5 Z9 6 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 MAY 20 PY 1998 VL 37 IS 15 BP 3272 EP 3275 DI 10.1364/AO.37.003272 PG 4 WC Optics SC Optics GA ZM902 UT WOS:000073587800026 PM 18273281 ER PT J AU Laming, JM AF Laming, JM TI A thermal model for the featureless X-ray emission from SN 1006? SO ASTROPHYSICAL JOURNAL LA English DT Article DE radiation mechanisms, nonthermal; shock waves; supernova, individual (SN 1006); X-rays, ISM ID YOUNG SUPERNOVA-REMNANTS; MAGNETIC-FIELDS; EJECTA; ACCELERATION; SN-1006; SHOCKS AB I discuss a thermal model for the continuous X-ray emission from SN 1006, which is also applicable to other supernova remnants (e.g., Cas A, IC 443) where power-law tails are observed at the high-energy end of the X-ray spectrum. It is essentially an updated version of the work of Hamilton and company. The mechanism for producing high-energy continua is thermal bremsstrahlung at the reverse shock, where the electron temperature might be considerably higher than at the forward shock if collisionless heating can occur, and line emission in the ASCA bandpass can be suppressed if the shocked material is carbon. For reasonable values of electron density and temperature, such as might be produced by shocks, the observed X-ray spectra of SN 1006 can be simulated, but morphological arguments and the mass of C required present difficulties for this model. The interpretation of the observed power-law continuum in SN 1006 as synchrotron radiation from cosmic-ray electrons is unchanged. For the other remnants, though, the mechanism discussed here might be much more viable and should certainly be considered. C1 SFA Inc, Largo, MD 20774 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Laming, JM (reprint author), SFA Inc, Largo, MD 20774 USA. NR 35 TC 27 Z9 27 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 MAY 20 PY 1998 VL 499 IS 1 BP 309 EP 314 DI 10.1086/305647 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZQ838 UT WOS:000073908100028 ER PT J AU Sellers, SP Korte, BJ Fitzgerald, JP Reiff, WM Yee, GT AF Sellers, SP Korte, BJ Fitzgerald, JP Reiff, WM Yee, GT TI Canted ferromagnetism and other magnetic phenomena in square-planar, neutral manganese(II) and iron(II) octaethyltetraazaporphyrins SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID PARAMAGNETIC ANISOTROPY; ELECTRONIC-STRUCTURE; SPIN; PHTHALOCYANINE; TETRACYANOETHENIDE; PRECURSORS; PORPHYRINS; BEHAVIOR; ALPHA; TC AB Iron(II) octaethyltetraazaporphyrin has been discovered-to exist as two polymorphs at room temperature, alpha- and beta-Fe(OETAP). This has been established by X-ray powder diffraction and scanning electron microscopy. Both ac and de SQUID magnetometry show that the alpha phase is a soft molecular ferromagnet with T-Curie = 2.8 K. The beta phase possesses the same number of unpaired spins and a similar g value, but it does not order above similar to 1 K. Zero-field splitting is Likely competing with ferromagnetic coupling in this compound. Fe-57 Mossbauer spectroscopy has been used to support the local structural similarity between the two phases and to study the ferromagnetic transition. The isomorphous manganese analogue of alpha-Fe(OETAP), alpha-Mn(OETAP), expected to be a ferromagnet with a higher T-Curie, exhibits many characteristics of ferromagnetism, notably hysteresis at 1.8 K with H-coer = 2.5 kG and M-rem = 4 kemu-G/mol. However, in contrast to ferromagnetic alpha-Fe(OETAP), alpha-Mn(OETAP) shows strongly frequency-dependent ac susceptibility in the range from 1 to 1000 Hz, indicating that it exists in a spin-glass-like state. This result underscores the need for frequency-dependent ac magnetometry to fully characterize ferromagnetic molecular materials. C1 Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. Northeastern Univ, Dept Chem, Boston, MA 02115 USA. RP Yee, GT (reprint author), Univ Colorado, Dept Chem & Biochem, Campus Box 215, Boulder, CO 80309 USA. NR 51 TC 38 Z9 38 U1 1 U2 15 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 MAY 20 PY 1998 VL 120 IS 19 BP 4662 EP 4670 DI 10.1021/ja973787a PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA ZP974 UT WOS:000073807700015 ER PT J AU Glazounov, AE Zhang, QM Kim, C AF Glazounov, AE Zhang, QM Kim, C TI Piezoelectric actuator generating torsional displacement from piezoelectric d(15) shear response SO APPLIED PHYSICS LETTERS LA English DT Article AB A torsional actuator generating angular displacement from piezoelectric shear strain was developed. The actuator is a tube consisting of an even number of segments poled along the length, which are adhesively bonded together, and the joints act as electrodes to apply the driving voltage. The experimental data measured on the prototype actuator: (i) prove the proposed concept of the torsional actuator, (ii) show that the actuator functions well under the torque lend, and (iii) demonstrate that it has superior characteristics compared to previously reported designs of torsional actuators. (C) 1998 American Institute of Physics. [S0003-6951(98)02620-5]. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. USN, Res Lab, Washington, DC 20375 USA. RP Glazounov, AE (reprint author), Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. NR 9 TC 30 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 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAY 18 PY 1998 VL 72 IS 20 BP 2526 EP 2528 DI 10.1063/1.121408 PG 3 WC Physics, Applied SC Physics GA ZN118 UT WOS:000073611700010 ER PT J AU Fong, CY Klein, BM Hemstreet, LA Yang, LH Nelson, JS AF Fong, CY Klein, BM Hemstreet, LA Yang, LH Nelson, JS TI Three interacting excitons in three coupled quantum dots SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID WELLS; CONFINEMENT; DIMENSIONS; STATES AB Using a scaled Kohn-Sham formalism, we examine three heavy-and light-hole excitons, respectively, in three coupled quantum dots to study the effects of competition involving the electron-electron and hole-hole interactions between excitons, the electron-hole interaction within excitons and the effective masses. The particle-particle interactions play dominant roles in determining the configuration of the excitons in the coupled dots. In the absence of an external electric field, the two lowest (occupied) energy states of the heavy-hole excitons are degenerate, and the excitons have an equal probability of residing in either of the two side dots. The corresponding states of the light-hole excitons exhibit nondegenerate character and the lowest energy exciton is confined predominantly to the centre dot. Under a weak de electric field, both the heavy-and light-hole excitons form direct excitons which are localized in the side dots. For large values of the electric field, we find that the electrons associated with the excitons become ionized as a result of strong confinement by the field and the electron-electron repulsion between excitons before the excitons can be transformed into indirect excitons. This result is in contrast to the conclusion that a single exciton in a double-quantum-well structure will be transformed into an indirect exciton in real space when it is subjected to large fields. Furthermore, we suggest that the wave function overlap between interacting excitons may diminish significantly the increase in excitonic lifetime predicted for a single exciton in two coupled quantum dot systems, implying that it may be difficult to make use of several excitons in coupled structures for nonlinear devices. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. USN, Res Lab, Cod 6877, Washington, DC 20375 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Sandia Natl Labs, Semicond Phys Div, Albuquerque, NM 87185 USA. RP Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. NR 25 TC 3 Z9 3 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 EI 1361-648X J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD MAY 18 PY 1998 VL 10 IS 19 BP 4335 EP 4352 DI 10.1088/0953-8984/10/19/021 PG 18 WC Physics, Condensed Matter SC Physics GA ZQ090 UT WOS:000073820400021 ER PT J AU Flatte, ME Byers, JM AF Flatte, ME Byers, JM TI Impurity effects on quasiparticle c-axis planar tunneling and STM spectra in high-T-c cuprates SO PHYSICAL REVIEW LETTERS LA English DT Article ID NONMAGNETIC IMPURITIES; ENERGY-GAP; SUPERCONDUCTOR; BI2SR2CACU2O8+DELTA; SPECTROSCOPY; ANISOTROPY; SCATTERING; STATES; WAVES AB We present self-consistent calculations of the electronic structure near strongly scattering impurities in cuprate superconductors described by a realistic band structure and order parameter magnitude. Energies and highly asymmetric line shapes of resonances, changes in gap-edge features, and local changes in the order parameter are determined for magnetic and nonmagnetic potentials. Experimental tunneling spectra are well fitted by calculations using a d-wave order parameter. The local density of states near such impurities is also calculated. C1 Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. USN, Res Lab, Washington, DC 20375 USA. RP Flatte, ME (reprint author), Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. NR 27 TC 45 Z9 45 U1 0 U2 1 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 MAY 18 PY 1998 VL 80 IS 20 BP 4546 EP 4549 DI 10.1103/PhysRevLett.80.4546 PG 4 WC Physics, Multidisciplinary SC Physics GA ZN308 UT WOS:000073632900047 ER PT J AU Browne, D Baatz, LM Millard, F Ward, FT AF Browne, D Baatz, LM Millard, F Ward, FT TI Oncology services - The department of defense perspective SO CANCER LA English DT Article; Proceedings Paper CT American-Cancer-Society National Conference on Purchasing Oncology Services - Current Methods and Models in the Marketplace CY SEP 11-12, 1997 CL CHICAGO, ILLINOIS SP Amer Canc Soc AB The Department of Defense (DoD) military health system has responsibility for providing medical care for more than 8 million beneficiaries. This article discusses initiatives related to both the providing and purchasing of oncology services. A description of health care coverage under TRICARE, the Department's managed care program, which utilizes military treatment facilities and civilian health care providers, is provided. Participation in clinical trials by the DoD beneficiaries, oncology services in military treatment facilities, quality management programs, cancer research, and the development of new technologies to enhance early cancer detection are presented. Access to research trials and new technologies is necessary for a comprehensive approach to cancer care. Clinical trials have been the vehicle by which the oncology community developed most of its formal clinical evidence for the efficacy of various treatment approaches. The Department participates in clinical trials through cooperative group membership or affiliation. Through an interagency agreement with the National Cancer Institute, DoD beneficiaries have available the option of participating in NCI-sponsored clinical trials through the direct military care system or through civilian care with reimbursement for approved protocols nationwide. The DoD has been actively involved in breast cancer research since 1992 and prostate and ovarian cancer research since 1997. The goals of the cancer research programs are to expedite and facilitate breakthroughs in research, support innovative, and exploratory ideas with a vision to foster new directions, address neglected issues, and bring new investigators into the research arena. The program incorporates the consumer perspective by involving consumers in the decision-making process. The DoD health care system trains experts in the management of cancer patients and provides a multidisciplinary approach to care through the direct military health care system or through network providers as part of the TRICARE system. Although cost containment is key, the delivery of high quality health care that is easily accessible is a primary goal of the military health system. Provision of a comprehensive benefits package that includes a spectrum of care and employing outcomes measurements to evaluate care that is appropriate for the patient's disease is essential. (C) 1998 American Cancer Society. C1 USA, Off Assistant Secretary Def, Washington, DC 20310 USA. USAF, Wright Patterson Hosp, Wright Patterson AFB, OH 45433 USA. USN, Naval Med Ctr, San Diego, CA 92152 USA. USA, Walter Reed Army Med Ctr, Washington, DC 20310 USA. RP Browne, D (reprint author), MCMR ZC, HQ, USAMRMC, 504 Scott St, Ft Detrick, MD 21702 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0008-543X J9 CANCER JI Cancer PD MAY 15 PY 1998 VL 82 IS 10 SU S BP 2010 EP 2015 PG 6 WC Oncology SC Oncology GA ZL633 UT WOS:000073454700006 PM 9587099 ER PT J AU McPhee, MG Stanton, TP Morison, JH Martinson, DG AF McPhee, MG Stanton, TP Morison, JH Martinson, DG TI Freshening of the upper ocean in the Arctic: Is perennial sea ice disappearing? SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MIXED-LAYER; TEMPERATURE; CO2 AB During the Surface Heat Budget of the Arctic (SHEBA) deployment in October, 1997, multiyear ice near the center of the Beaufort Gyre was anomalously thin. The upper ocean was both warmer and less saline than in previous years. The salinity deficit in the upper 100 m, compared with the same region during the Arctic Ice Dynamics Joint Experiment (AIDJEX) in 1975, is equivalent to surface input of about 2.4 m of fresh water. Heat content has increased by 67 MJ m(-2). During AIDJEX the change in salinity over the melt season implied melt equivalent to about 0.8 m of fresh water. As much as 2 m of freshwater input may have occurred during the 1997 summer, possibly resulting from decreased ice concentration from changes in atmospheric circulation early in the summer, in the classic albedo-feedback scenario. Unchecked, the pattern could lead to a significantly different sea-ice regime in the central Arctic. C1 McPhee Res Co, Naches, WA 98937 USA. USN, Postgrad Sch, Dept Oceanog, Stanford, CA 94305 USA. Univ Washington, Appl Phys Lab, Polar Sci Ctr, Seattle, WA 98105 USA. Lamont Doherty Earth Observ, Palisades, NY 10964 USA. RP McPhee, MG (reprint author), McPhee Res Co, 450 Clover Springs Rd, Naches, WA 98937 USA. NR 18 TC 106 Z9 115 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 15 PY 1998 VL 25 IS 10 BP 1729 EP 1732 DI 10.1029/98GL00933 PG 4 WC Geosciences, Multidisciplinary SC Geology GA ZN248 UT WOS:000073626900048 ER PT J AU Leonhardt, D Eddy, CR Shamamian, VA Holm, RT Glembocki, OJ Thoms, DB Katzer, DS Butler, JE AF Leonhardt, D Eddy, CR Shamamian, VA Holm, RT Glembocki, OJ Thoms, DB Katzer, DS Butler, JE TI Ion energy effects on surface chemistry and damage in a high density plasma etch process for gallium arsenide SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS LA English DT Article DE in situ mass spectrometry; photoreflectance; high density plasma etching; gallium arsenide; surface damage; etch products; chlorine passivation; surface Fermi level ID MODULATION SPECTROSCOPY; PHOTOREFLECTANCE; GAAS AB Etch product chlorides from a gallium arsenide substrate subjected to a high density Cl-2/Ar plasma etching process have been sampled in sial to determine regions of process space commensurate with ion-driven surface chemistry. Experimental results show three distinct surface chemistry regimes as the ion energy is increased: thermal chemistry for energies <50 eV, ion-assisted chemistry for energies of 50-200 eV, and sputtering for energies above 200 eV. Further, ion energies above 200 eV result in unrecoverable pinning of the surface Fermi level whereas at lower ion energies the surface Fermi level returns to the pre-etch condition with in situ Cl-2/Ar plasma passivations. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Leonhardt, D (reprint author), USN, Res Lab, Div Chem, Code 6174, Washington, DC 20375 USA. RI Butler, James/B-7965-2008; Katzer, D. Scott/N-7841-2013 OI Butler, James/0000-0002-4794-7176; NR 11 TC 2 Z9 2 U1 0 U2 1 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN J9 JPN J APPL PHYS 2 JI Jpn. J. Appl. Phys. Part 2 - Lett. PD MAY 15 PY 1998 VL 37 IS 5B BP L577 EP L579 DI 10.1143/JJAP.37.L577 PG 3 WC Physics, Applied SC Physics GA 102TL UT WOS:000074941300005 ER PT J AU Gardner, JA Edwards, A Rao, MV Papanicolaou, N Kelner, G Holland, OW Capano, MA Ghezzo, M Kretchmer, J AF Gardner, JA Edwards, A Rao, MV Papanicolaou, N Kelner, G Holland, OW Capano, MA Ghezzo, M Kretchmer, J TI Material and n-p junction properties of N-, P-, and N/P-implanted SiC SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TEMPERATURE AB Elevated temperature (ET) multiple energy N, P, and N/P implantations were performed into p-type 6H-SiC epitaxial layers. For comparison, room temperature (RT) N and P implantations were also performed. In the N/P coimplanted material a sheet resistance of 2.1X10(2) Ohm/square was measured, which is lower compared to the values measured in N or P implanted material of the same net donor dose. The RT P implantation resulted in heavy lattice damage and consequently low P electrical activation, even after 1600 degrees C annealing. After annealing the Rutherford backscattering yield either coincided or came close to the virgin level for ET implantations and RT N implantation, whereas for RT P implantation the yield was high, indicating the presence of high residual damage. Vertical n-p junction diodes were made by selective area ET N, P, and N/P implantations and RT N and P implantations using a 2.5 mu m thick SiO2 layer as an implant mask. The diodes were characterized by capacitance-voltage and variable temperature current-voltage measurements. (C) 1998 American Institute of Physics. C1 George Mason Univ, Dept Elect & Comp Engn, Fairfax, VA 22030 USA. USN, Res Lab, Washington, DC 20375 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. AFRL, MLPO, Wright Patterson AFB, OH 45433 USA. GE, Corp Res & Dev, Schenectady, NY 12301 USA. RP Gardner, JA (reprint author), George Mason Univ, Dept Elect & Comp Engn, Fairfax, VA 22030 USA. NR 14 TC 41 Z9 41 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1998 VL 83 IS 10 BP 5118 EP 5124 DI 10.1063/1.367329 PG 7 WC Physics, Applied SC Physics GA ZP639 UT WOS:000073773600016 ER PT J AU Leuchtner, RE Horwitz, JS Chrisey, DB AF Leuchtner, RE Horwitz, JS Chrisey, DB TI Particulate distributions in Pt films prepared by pulsed laser deposition SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID THIN-FILMS; ABLATION DEPOSITION; EMISSION; METALS AB A quantitative statistical analysis of micron-sized particulates on the surface of oriented platinum thin films prepared on [100] MgO at 450 degrees C was made. The particulates, resulting from nanosecond laser ablation, were evaluated as a function of laser fluence (0.75-3.00 J/cm(2)) to determine the average diameter, spatial distribution relative to the center of the ablation plume, and areal density. The latter quantity is defined as the number of particulates per cm(2) of him surface per nanometer of film thickness. The particulate shape was generally spherical with a diameter range of similar to 0.05-1.0 mu m. For a given laser fluence, the areal density was roughly constant from the plume center outwards suggesting that particulate reduction by growing films in off-axis regions may be problematic. Increasing the laser fluence from 0.75 to 3.00 J/cm(2) however, resulted in a two order of magnitude reduction in the areal density, although an increase in the average particulate diameter from 0.26 to 0.47 mu m occurred. This result implies that, at least with metals, increasing laser fluence is a pragmatic approach to particulate reduction in laser deposited thin films. (C) 1998 American Institute of Physics. C1 Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. USN, Res Lab, Div Condensed Matter & Radiat Sci, Washington, DC 20375 USA. RP Leuchtner, RE (reprint author), Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. EM robert.leuchtner@unh.edu NR 18 TC 21 Z9 21 U1 0 U2 5 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 MAY 15 PY 1998 VL 83 IS 10 BP 5477 EP 5483 DI 10.1063/1.367405 PG 7 WC Physics, Applied SC Physics GA ZP639 UT WOS:000073773600069 ER PT J AU Hwang, PA Teague, WJ Jacobs, GA Wang, DW AF Hwang, PA Teague, WJ Jacobs, GA Wang, DW TI A statistical comparison of wind speed, wave height, and wave period derived from satellite altimeters and ocean buoys in the Gulf of Mexico region SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SEA-SURFACE; MODEL; SLOPE; VALIDATION; ALGORITHM; WAM AB The capability of spaceborne altimeters tb provide precise measurement of significant wave height and wind speed has been demonstrated repeatedly. It is shown in this paper that in addition to the significant wave height and wind speed, the wave period can be calculated from the semiempirical functions established from earlier wave research. The calculated characteristic wave period using the altimeter-derived wind speed and wave height are found to be in excellent agreement with the peak wave period and average wave period from the ocean buoy measurements in the Gulf of Mexico. Also, with the long time series of collocated data set, it is possible to compare altimeter output of wind and wave parameters with ocean buoy measurements taking into consideration the spatial lags between the buoy locations and the altimeter footprints, and the temporal lags between the two sensor systems. It is found that when the spatial lags are less than 10 km, the RMS difference of the significant wave height is approximately 0.1 m, which is the digitization resolution of the output from both altimeter and ocean buoy. For the wind speed, the RMS difference approaches 1.2 m/s in the Gulf of Mexico using the empirical algorithms. The wind speed agreement is significantly improved to 0.8 m/s when the tilting effect on the altimeter cross section is accounted for. In contrast to the spatial lags, temporal lags of up to I hour do not appear to produce significant difference in the statistics of comparison based on this study. C1 USN, Res Lab, Div Oceanog, Stennis Space Ctr, MS 39529 USA. Comp Sci Corp, Stennis Space Ctr, MS 39529 USA. RP Hwang, PA (reprint author), USN, Res Lab, Div Oceanog, Code 7300, Stennis Space Ctr, MS 39529 USA. RI Jacobs, Gregg/C-1456-2008 NR 32 TC 76 Z9 87 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 MAY 15 PY 1998 VL 103 IS C5 BP 10451 EP 10468 DI 10.1029/98JC00197 PG 18 WC Oceanography SC Oceanography GA ZN319 UT WOS:000073634000016 ER PT J AU Altmann, KL Chafin, AP Merwin, LH Wilson, WS Gilardi, R AF Altmann, KL Chafin, AP Merwin, LH Wilson, WS Gilardi, R TI Chemistry of tetraazapentalenes SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID VICARIOUS NUCLEOPHILIC-SUBSTITUTION; HIGH-DENSITY; DERIVATIVES; OXIDATION; AMINATION; HYDROGEN AB 2,4,8, 10-Tetranitrobenzotriazolo[2, 1-alpha]benzotriazole (TACOT), although thermally very stable and insensitive as an explosive, is susceptible to attack by nucleophiles. Reaction with azide ion results in displacement of nitro groups at the 4,10-positions, treatment with methoxide ion effects displacement of the hydrogen atom at the 1-position and scission of the remote triazole ring, while "vicarious nucleophilic amination" displaces all the aromatic hydrogens. 3,5,7-Trinitro-1,3,3-triazolo[2, 1-alpha]benzotriazole and 3,5,7-trinitro-1,2,3-triazolo[1,2-alpha]benzotriazole are prepared readily by nitration of the parent triazolobenzotriazoles. However they are thermally less stable than TACOT and more sensitive to initiation by impact. Furthermore, attempted further nitration and reaction with nucleophiles such as azide and methoxide ions both effect scission of the triazole ring to leave 4,6-dinitrobenzotriazole. C1 USN, Air Warfare Ctr Weapons Div, Res & Technol Grp, China Lake, CA 93555 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Wilson, WS (reprint author), USN, Air Warfare Ctr Weapons Div, Res & Technol Grp, China Lake, CA 93555 USA. NR 22 TC 14 Z9 14 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD MAY 15 PY 1998 VL 63 IS 10 BP 3352 EP 3356 DI 10.1021/jo972252x PG 5 WC Chemistry, Organic SC Chemistry GA ZP599 UT WOS:000073769600033 ER PT J AU Statman, D Lombardi, JC Gilbreath, GC AF Statman, D Lombardi, JC Gilbreath, GC TI Signature of memory for photorefractive two beam coupling: computational and experimental results SO OPTICS COMMUNICATIONS LA English DT Article ID PHASE CONJUGATION; STEADY-STATE; 2-WAVE; AMPLIFICATION; CRYSTALS; BATIO3; MEDIA AB We have conducted numerical calculations describing photorefractive two beam coupling under high gain conditions and compared them with experimental results generated in our laboratory. A complete modeling of the photorefractive rate equations, which generalizes the modeling to include nonlinear terms and relaxes the non-depleting pump approximation, demonstrates a memory effect in the time dependence of the two beam coupling gain. This memory effect shows that time dependence of the two beam coupling gain is characterized by an 'S' curve. In addition, the nonlinear terms contribute a tail in the growth of the two beam coupled signal which results in predicted gains about 10% higher than expected for the linear model. Experimental results are shown to agree with the modeling. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Allegheny Coll, Dept Phys, Meadville, PA 16335 USA. USN, Res Lab, Naval Ctr Space Technol, Washington, DC 20375 USA. RP Statman, D (reprint author), Allegheny Coll, Dept Phys, Meadville, PA 16335 USA. EM dstatman@alleg.edu NR 27 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD MAY 15 PY 1998 VL 151 IS 1-3 BP 69 EP 74 DI 10.1016/S0030-4018(98)00081-9 PG 6 WC Optics SC Optics GA ZY489 UT WOS:000074626900015 ER PT J AU Bickham, SR Feldman, JL AF Bickham, SR Feldman, JL TI Calculation of vibrational lifetimes in amorphous silicon using molecular dynamics simulations SO PHYSICAL REVIEW B LA English DT Article ID COMPUTER-SIMULATION; LATTICE-DYNAMICS; LOW-TEMPERATURE; SI; GLASSES; PHONONS; DENSITY; SOLIDS; STATES; DECAY AB The decay of normal-mode excitations is calculated for amorphous silicon through molecular-dynamics simulations within periodic supercells consisting of 216 and 4096 atoms. Phenomenological structural and interatomic potential models are employed. At moderate temperatures, lifetimes an found to be on the order of 10 ps and lifetimes of localized and extended nonpropagating modes are comparable. These features are in agreement with related perturbation theory calculations, and in strong disagreement with the frustrated anharmonic decay predicted by the fracton model and apparently with the results of anti-Stokes Raman experiments performed at T=10 K. [S0163-1829(98)01319-8]. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Bickham, SR (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. NR 26 TC 16 Z9 16 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 MAY 15 PY 1998 VL 57 IS 19 BP 12234 EP 12238 DI 10.1103/PhysRevB.57.12234 PG 5 WC Physics, Condensed Matter SC Physics GA ZP518 UT WOS:000073761500068 ER PT J AU Papaconstantopoulos, DA Pickett, WE AF Papaconstantopoulos, DA Pickett, WE TI Tight-binding coherent potential approximation study of ferromagnetic La2/3Ba1/3MnO3 SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; LA1-XSRXMNO3; LA1-XCAXMNO3; RESISTIVITY; TRANSPORT; FILMS AB The local-spin-density band structure of a virtual-crystal model of ferromagnetic La2/3Ba1/3MnO3, reported earlier by Pickett and Singh [Phys. Rev. B 53, 1146 (1996)], has been fit to an accurate orthogonal tight-binding (TB) model. This TB Hamiltonian has spin-independent hopping parameters, and the exchange splitting is confined solely to the Mn on-site parameters epsilon(t2g down arrow) - epsilon(t2g up arrow) = 3.44 eV and epsilon(eg down arrow) - epsilon(eg up arrow) = 2.86 eV. The crystal-field splitting, as reflected in the Mn d energies, is 1.77 eV for majority spin and 1.19 eV for minority spin. Oxygen p sigma and p pi states are allowed distinct site energies, and the derived crystal-field splitting is epsilon(p pi) - epsilon(p sigma) = 1.47 eV. Local Mn d site energy disorder, arising from the random distribution of La3+ and Ba2+ ions, has been treated within the TB coherent potential approximation. The intrinsic resistivity in the fully polarized phase from this charge disorder is estimated to be 15 mu Ohm cm. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Papaconstantopoulos, DA (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. NR 28 TC 31 Z9 31 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 MAY 15 PY 1998 VL 57 IS 20 BP 12751 EP 12756 DI 10.1103/PhysRevB.57.12751 PG 6 WC Physics, Condensed Matter SC Physics GA ZR644 UT WOS:000073999400022 ER PT J AU Lupton, JE Baker, ET Garfield, N Massoth, GJ Feely, RA Cowen, JP Greene, RR Rago, TA AF Lupton, JE Baker, ET Garfield, N Massoth, GJ Feely, RA Cowen, JP Greene, RR Rago, TA TI Tracking the evolution of a hydrothermal event plume with a RAFOS neutrally buoyant drifter SO SCIENCE LA English DT Article ID DE-FUCA RIDGE; 1993 COAXIAL EVENT; BAROCLINIC VORTEX; CLEFT SEGMENT; VENT PLUMES; JUAN; MANGANESE; SEA; MEGAPLUMES; MODEL AB The migration and evolution of a deep ocean hydrothermal event plume were tracked with a neutrally buoyant RAFOS float. The float remained entrained in the plume for 60 days, and the plume vorticity was calculated directly from the anticyclonic motion of the float. Concentrations of suspended particles, particulate iron, and dissolved manganese in the plume did not decay significantly during the 60 days, which indicates that event plumes would be easily detectable a year after formation. C1 NOAA, Pacific Marine Environm Lab, Newport, OR 97365 USA. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. USN, Postgrad Sch, Monterey, CA 93943 USA. Univ Hawaii, Dept Oceanog, Honolulu, HI 96822 USA. RP Lupton, JE (reprint author), NOAA, Pacific Marine Environm Lab, Newport, OR 97365 USA. NR 34 TC 27 Z9 27 U1 0 U2 5 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAY 15 PY 1998 VL 280 IS 5366 BP 1052 EP 1055 DI 10.1126/science.280.5366.1052 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZN615 UT WOS:000073663600039 ER PT J AU Bhar, TN Lambert, RJ Hughes, HL AF Bhar, TN Lambert, RJ Hughes, HL TI Electron trapping in SI implanted SIMOX SO ELECTRONICS LETTERS LA English DT Article ID BURIED OXIDES AB The implantation and annealing processes of SIMOX fabrication may result in excess silicon atoms located in the buried oxide. These excess silicon atoms have been postulated by various researchers to be responsible for the formation of silicon clusters and associated defects in SIMOX [1-3]. This work was performed to test this postulate. These defects result in a higher refractive index [4], an increase in the number of electron traps, and the production of traps with very large capture cross-sections. It is also known that excess silicon introduced by ion implantation creates electron traps in thermal oxides [5, 6]. This work supports the above postulate by implanting a large range of silicon concentrations into low defect multiple implant SIMOX and measuring the resulting electron traps by the avalanche injection technique. C1 Univ Dist Columbia, Washington, DC 20008 USA. USN, Res Lab, Washington, DC 20375 USA. RP Bhar, TN (reprint author), Univ Dist Columbia, Washington, DC 20008 USA. NR 9 TC 3 Z9 3 U1 0 U2 1 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD MAY 14 PY 1998 VL 34 IS 10 BP 1026 EP 1027 DI 10.1049/el:19980626 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA ZR317 UT WOS:000073962000064 ER PT J AU Karle, IL Perozzo, MA Mishra, VK Balaram, P AF Karle, IL Perozzo, MA Mishra, VK Balaram, P TI Crystal structure of the channel-forming polypeptide antiamoebin in a membrane-mimetic environment SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID PEPTIDE; ALPHA; CONFORMATION; RESOLUTION; REFINEMENT AB Crystals of an ion-channel-forming peptaibol peptide in a partial membrane environment have been obtained by cocrystallizing antiamoebin with n-octanol, The antiamoebin molecule has a bent helical conformation very similar to that established for Leu-zervamicin, despite a significantly different sequence for residues 1-8, The bent helices assemble to form a polar channel in the shape of an hour glass that is quite comparable to that of Leu-zervamicin. The molecules of cocrystallized octanol are found in two different areas with respect to the assembly of peptide molecules. One octanol molecule mimics a membrane segment along the hydrophobic exterior of the channel assembly. The other octanol molecules fill the channel in such a way that their OH termini satisfy the C=O moieties directed into the interior of the channel. Structure parameters for C82H27N17O20. 3C(8)H(18)O are space group P2(1)2(1)2(1), a = 9.143(2) Angstrom, b = 28.590(8) Angstrom, c = 44.289(8) Angstrom, Z = 4, agreement factor R-1 = 11.95% for 4,113 observed reflections [>4 sigma(F)], resolution similar to 1.0 Angstrom. C1 USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. Indian Inst Sci, Mol Biophys Unit, Bangalore 560012, Karnataka, India. RP Karle, IL (reprint author), USN, Res Lab, Struct Matter Lab, Code 6030, Washington, DC 20375 USA. FU NIGMS NIH HHS [GM30902, R01 GM030902, R37 GM030902] NR 18 TC 59 Z9 59 U1 0 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 MAY 12 PY 1998 VL 95 IS 10 BP 5501 EP 5504 DI 10.1073/pnas.95.10.5501 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZM977 UT WOS:000073595500017 PM 9576911 ER PT J AU Frenck, RW Blackburn, EH Shannon, KM AF Frenck, RW Blackburn, EH Shannon, KM TI The rate of telomere sequence loss in human leukocytes varies with age SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID BONE-MARROW; CELLS; CHROMOSOME-7; MONOSOMY-7; LEUKEMIA; REPEATS; RAP1 AB A gradual loss of telomeric repeat sequences with aging previously has been noted in normal adult tissues, and this process has been implicated in cell senescence. No data exist that address the rate of telomere shortening in normal human cells within families or early in life. To address these questions, we measured telomere lengths in peripheral blood leukocytes (PBLs) from 75 members of 12 families and in a group of unrelated healthy children who were 5-48 months old. Here we report the surprising observation that rates of telomere attrition vary markedly at different ages, Telomeric repeats are lost rapidly (at a rate of >1 kilobase per year) from the PBLs of young children, followed by an apparent plateau between age 4 and young adulthood, and by gradual attrition later in life. These data suggest that the loss of telomeric repeats in hematopoietic cells is a dynamic process that is differentially regulated in young children and adults. Our results have implications for current models of how telomeric sequences are lost in normal somatic cells and suggest that PBLs are an excellent tissue to investigate how this process is controlled. C1 Univ Calif San Francisco, Dept Pediat, San Francisco, CA 94143 USA. USN Hosp, Dept Clin Invest, Oakland, CA 94627 USA. Univ Calif San Francisco, Dept Immunol Microbiol, San Francisco, CA 94143 USA. RP Shannon, KM (reprint author), Univ Calif San Francisco, Dept Pediat, Box 0519,Room HSE-302, San Francisco, CA 94143 USA. FU NIGMS NIH HHS [GM26259, R01 GM026259, R37 GM026259] NR 24 TC 330 Z9 339 U1 2 U2 17 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 MAY 12 PY 1998 VL 95 IS 10 BP 5607 EP 5610 DI 10.1073/pnas.95.10.5607 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZM977 UT WOS:000073595500036 PM 9576930 ER PT J AU Olafsen, LJ Aifer, EH Vurgaftman, I Bewley, WW Felix, CL Meyer, JR Zhang, D Lin, CH Pei, SS AF Olafsen, LJ Aifer, EH Vurgaftman, I Bewley, WW Felix, CL Meyer, JR Zhang, D Lin, CH Pei, SS TI Near-room-temperature mid-infrared interband cascade laser SO APPLIED PHYSICS LETTERS LA English DT Article ID QUANTUM AB A 25-stage interband cascade laser with a W active region and a third hole quantum well for the suppression of leakage current has exhibited lasing in pulsed mode up to 286 K. A peak output power of 160 mW/facet and a slope efficiency of 197 mW/A per facet (1.1 photons per injected electron) were measured at 196 K. Above 200 K, the characteristic temperature was higher (T-0 = 53 K) and the threshold current densities lower than for a previously reported W interband cascade laser without the third hole quantum well. (C) 1998 American Institute of Physics. [S0003-6951(98)02519-4]. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Houston, Ctr Space Vacuum Epitaxy, Houston, TX 77204 USA. RP USN, Res Lab, Code 5613, Washington, DC 20375 USA. EM blue@tantalus.nrl.navy.mil RI Olafsen, Linda/G-4996-2013 NR 16 TC 108 Z9 110 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAY 11 PY 1998 VL 72 IS 19 BP 2370 EP 2372 DI 10.1063/1.121359 PG 3 WC Physics, Applied SC Physics GA ZM442 UT WOS:000073540600006 ER PT J AU Hasan, Z Solonenko, M Macfarlane, PI Biyikli, L Mathur, VK Karwacki, FA AF Hasan, Z Solonenko, M Macfarlane, PI Biyikli, L Mathur, VK Karwacki, FA TI Persistent high density spectral holeburning in CaS : Eu and CaS : Eu,Sm phosphors SO APPLIED PHYSICS LETTERS LA English DT Article ID STIMULATED LUMINESCENCE; STORAGE AB Persistent spectral hole-burning has been reported for singly, flu-doped, and doubly, Eu-and Sm-doped, CaS phosphors. Efficient photon gated holeburning in the 4f(7) (S-8(7/2)) - 4f(6)5d(1) transition of Eu2+ is a result of photoionization of Eu2+ to Eu3+. These holes have a width of <5 GHz (2 K), survive thermal cycling of the phosphor up to the room temperature, 300 K, and have no detectable deterioration over more than a day of storage time at low temperature (2 K). Although self-gated holeburning is observed with the reading laser at higher powers, the photon budget for reading these holes is so small that in excess of 1000 reading cycles can De performed without destroying the optical signal. The nature of holes burned by photon-gating is found to be very different from the self-gated holes. The characteristics for the holeburning are the same in singly and doubly doped phosphors, suggesting that under the conditions of our experiments, Sm traps do not play any significant role in spectral holeburning. Possibilities of high density optical memory storage using photon-gated holeburning in this THz broad transition are discussed. (C) 1998 American Institute of Physics. [S0003-6951(98)02019-1]. C1 Temple Univ, Dept Phys, Philadelphia, PA 19122 USA. USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. USN, Air Warfare Ctr, Aircraft Div, Patuxent River, MD 20670 USA. RP Temple Univ, Dept Phys, Philadelphia, PA 19122 USA. NR 9 TC 37 Z9 38 U1 1 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAY 11 PY 1998 VL 72 IS 19 BP 2373 EP 2375 DI 10.1063/1.121360 PG 3 WC Physics, Applied SC Physics GA ZM442 UT WOS:000073540600007 ER PT J AU Wang, YM Sheeley, NR Walters, JH Brueckner, GE Howard, RA Michels, DJ Lamy, PL Schwenn, R Simnett, GM AF Wang, YM Sheeley, NR Walters, JH Brueckner, GE Howard, RA Michels, DJ Lamy, PL Schwenn, R Simnett, GM TI Origin of streamer material in the outer corona SO ASTROPHYSICAL JOURNAL LA English DT Article DE interplanetary medium; solar wind; Sun, corona; Sun, magnetic fields ID SOLAR-WIND AB We investigate the nature and origin of the outward-moving density inhomogeneities ("blobs") detected previously with the Large Angle and Spectrometric Coronagraph on the Solar and Heliospheric Observatory. The blobs are concentrated around the thin plasma layer that surrounds the heliospheric current sheet and that constitutes the outer streamer belt; they represent only a small, fluctuating component of the total density within the plasma sheet. As noted before in Sheeley et al., blobs are characterized by low speeds and are continually emitted from the elongated tips of helmet streamers at 3-4 R. from Sun center. We suggest that both the blobs and the plasma sheet itself represent closed-field material injected into the solar wind as a result of footpoint exchanges between the stretched helmet-streamer loops and neighboring open field lines. The plasma sheet is thus threaded by newly reconnected, open magnetic field lines, which lend the white-light streamer belt its filamentary appearance. Since in situ observations at 1 AU show that the slow wind (with speeds below 500 km s(-1)) spreads over an angular extent much greater than the less than or similar to 3 degrees width of the plasma sheet, we deduce that a major component of this wind must originate outside the helmet streamers (i.e., from just inside coronal holes). C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Astron Spatiale Lab, F-37189 Marseille 12, France. Max Planck Inst Aeron, D-37189 Katlenburg Lindau, Germany. Univ Birmingham, Sch Phys & Space Res, Birmingham B15 2TT, W Midlands, England. RP Wang, YM (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 18 TC 158 Z9 161 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 MAY 10 PY 1998 VL 498 IS 2 BP L165 EP + DI 10.1086/311321 PN 2 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZN687 UT WOS:000073671600015 ER PT J AU Narayan, SP Basu, K Prasad, YVRK Jayaram, V Das, BN AF Narayan, SP Basu, K Prasad, YVRK Jayaram, V Das, BN TI A study of the formability of melt spun Nd-Fe-B magnets SO SCRIPTA MATERIALIA LA English DT Article ID 304L STAINLESS-STEEL; HOT-WORKING; PERMANENT-MAGNETS; PROCESSING MAP; AISI-304; BEHAVIOR C1 Reg Res Lab, Bhopal 462026, India. Indian Inst Sci, Bangalore 560012, Karnataka, India. USN, Res Lab, Washington, DC 20375 USA. RP Reg Res Lab, Bhopal 462026, India. NR 19 TC 2 Z9 2 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD MAY 5 PY 1998 VL 38 IS 11 BP 1725 EP 1730 DI 10.1016/S1359-6462(98)00098-0 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA ZQ064 UT WOS:000073817800017 ER PT J AU Miller, AR Moskowitz, IS AF Miller, AR Moskowitz, IS TI On certain generalized incomplete gamma functions SO JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS LA English DT Article DE generalized incomplete gamma functions; Bessel functions; Kampe de Feriet functions ID LIPSCHITZ-HANKEL INTEGRALS; CYLINDRICAL-FUNCTIONS AB Recently, Chaudhry and Zubair have introduced a generalized incomplete gamma function Gamma(v,x;z) which reduces to the incomplete gamma function Gamma(v,x) when its variable z vanishes. We show that Gamma(v,x;z) may be written essentially as a single Kampe de Feriet function which in turn may be expressed as a linear combination of two incomplete Weber integrals. Then by using properties of the latter integrals we deduce additional representations for Gamma(v,x;z). In particular, we show that Gamma(v,x;z) is essentially completely determined by a finite number of modified Bessel functions for all v not equal 0 provided we know the values of the two incomplete Weber integrals when 0 < Re v less than or equal to 1. When v = 0 we derive connections between the generalized incomplete gamma function and incomplete Lipschitz-Hankel integrals, and indicate that there exist connections with other special functions. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Informat Technol, Ctr High Assurance Comp Syst, Washington, DC 20375 USA. NR 11 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0427 J9 J COMPUT APPL MATH JI J. Comput. Appl. Math. PD MAY 4 PY 1998 VL 91 IS 2 BP 179 EP 190 DI 10.1016/S0377-0427(98)00031-4 PG 12 WC Mathematics, Applied SC Mathematics GA ZW200 UT WOS:000074385700001 ER PT J AU Rajagopal, AK Mendes, RS Lenzi, EK AF Rajagopal, AK Mendes, RS Lenzi, EK TI Quantum statistical mechanics for nonextensive systems: Prediction for possible experimental tests SO PHYSICAL REVIEW LETTERS LA English DT Article ID BOSE-EINSTEIN CONDENSATION; ANOMALOUS DIFFUSION; THERMODYNAMICS AB The traditional basis of description of the many-particle systems in terms of the Green functions is here generalized when the system is nonextensive by incorporating the Tsallis form of the density matrix, indexed by a nonextensive parameter, q. This extension enables us to predict possible experimental tests for the validity of this framework by expressing some observable quantities in terms of the q averages. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Estadual Maringa, Dept Fis, BR-87020900 Maringa, Parana, Brazil. Ctr Brasileiro Pesquisas Fis, BR-22290180 Rio De Janeiro, Brazil. RP Rajagopal, AK (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 33 TC 56 Z9 56 U1 0 U2 3 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 MAY 4 PY 1998 VL 80 IS 18 BP 3907 EP 3910 DI 10.1103/PhysRevLett.80.3907 PG 4 WC Physics, Multidisciplinary SC Physics GA ZK808 UT WOS:000073365800005 ER PT J AU Johnson, GA Mar, DJ Carroll, TL Pecora, LM AF Johnson, GA Mar, DJ Carroll, TL Pecora, LM TI Synchronization and imposed bifurcations in the presence of large parameter mismatch SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHAOTIC SYSTEMS; OSCILLATORS; HYPERCHAOS AB Using experimental and numerical systems, we show that it is possible to maintain excellent synchronization between a drive and a response system even when there is a large (50%) parameter mismatch between them, and they are coupled only through a scalar signal. By optimizing the coupling consistent with a stability constraint, we show that a consequence of the optimized coupling is that the synchronization is maintained even in the presence of bifurcations in the drive system, despite the condition that the response parameters are held constant. C1 USN, Res Lab, Washington, DC 20375 USA. RP Johnson, GA (reprint author), USN, Res Lab, Code 6343, Washington, DC 20375 USA. OI Carroll, Thomas/0000-0002-2371-2049 NR 19 TC 62 Z9 63 U1 0 U2 3 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 MAY 4 PY 1998 VL 80 IS 18 BP 3956 EP 3959 DI 10.1103/PhysRevLett.80.3956 PG 4 WC Physics, Multidisciplinary SC Physics GA ZK808 UT WOS:000073365800017 ER PT J AU Gaston, B Sears, S Woods, J Hunt, J Ponaman, M McMahon, T Stamler, JS AF Gaston, B Sears, S Woods, J Hunt, J Ponaman, M McMahon, T Stamler, JS TI Bronchodilator S-nitrosothiol deficiency in asthmatic respiratory failure SO LANCET LA English DT Article ID NITRIC-OXIDE; NITROSOGLUTATHIONE AB Background Nitric oxide (NO) gas concentrations are high in the expired air of individuals with asthma, but not consistently so in the expired air of people with pneumonia. S-nitrosothiols are naturally occurring bronchodilators, the concentrations of which are raised in the airways of patients with pneumonia. Airway S-nitrosothiols have not been studied in asthma. Methods Tracheal S-nitrosothiol concentrations from eight asthmatic children in respiratory failure were compared with those of 21 children undergoing elective surgery. Results Mean S-nitrosothiol concentrations in asthmatic children were lower than in normal children (65 [SD 45] nmol/L vs 502 [SD 429] nmol/L) and did not vary with inspired oxygen concentration or airway thiol concentration. Interpretation Severe asthma is associated with low concentrations of airway S-nitrosothiols. This is the first reported deficiency of an endogenous bronchodilator in the human asthmatic airway lining fluid, We suggest that S-nitrosothiol metabolism may be a target for the development of new asthma therapies. C1 Univ Virginia Hlth Syst, Charlottesville, VA 22908 USA. USN, Med Ctr, Dept Pediat, Div Pulm, San Diego, CA 92152 USA. Duke Univ, Med Ctr, Howard Hughes Med Inst, Durham, NC USA. Duke Univ, Med Ctr, Dept Med, Durham, NC USA. RP Gaston, B (reprint author), Univ Virginia Hlth Syst, Box 386, Charlottesville, VA 22908 USA. EM bmg3g@virginia.edu RI McMahon, Timothy/K-3986-2012 OI McMahon, Timothy/0000-0002-3404-3223 FU NHLBI NIH HHS [HL52529, HLO2582] NR 27 TC 167 Z9 170 U1 0 U2 2 PU LANCET LTD PI LONDON PA 42 BEDFORD SQUARE, LONDON WC1B 3SL, ENGLAND SN 0140-6736 J9 LANCET JI Lancet PD MAY 2 PY 1998 VL 351 IS 9112 BP 1317 EP 1319 DI 10.1016/S0140-6736(97)07485-0 PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA ZL499 UT WOS:000073439400009 PM 9643794 ER PT J AU Kampe, SL Christodoulou, J Feng, CR Christodoulou, L Michel, DJ AF Kampe, SL Christodoulou, J Feng, CR Christodoulou, L Michel, DJ TI The effect of matrix microstructure and reinforcement shape on the creep deformation of near-gamma titanium aluminide composites SO ACTA MATERIALIA LA English DT Article ID DISLOCATION CONFIGURATIONS; LAMELLAR MICROSTRUCTURE; TIAL ALLOYS; STRENGTH; BEHAVIOR; TEMPERATURE AB The influences of composite matrix microstructure, reinforcement shape, and processing methodology have been evaluated for a series of near-gamma (Ti3Al + TiAl) titanium aluminide matrix composites evaluated in tension and tensile-creep at 800 degrees C. Specifically, heat treatments were imposed to evolve either fully-equiaxed or fully-lamellar composite matrices containing either dispersed particulate or high-aspect-ratio short-fiber boride reinforcement. The results indicate that the highest creep rates are associated with composites containing particulate reinforcement in equiaxed matrices, whereas the lowest rates were obtained for short-fiber reinforcement in lamellar matrices. The mechanisms controlling creep deformation are observed to rely only on the morphology and details of the matrix microstructure and are independent of the type and shape of the reinforcing phase. The enhanced work hardening tendencies of the lamellar microstructure is shown to improve creep resistance as manifested by a reduced steady state creep rate as well as prolonging primary creep to higher values of accumulated strain. (C) 1998 Acta Metallurgica Inc. C1 Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. USN, Res Labs, Washington, DC 20375 USA. Off Naval Res Europe, London, England. Univ London Imperial Coll Sci Technol & Med, London, England. RP Kampe, SL (reprint author), Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. NR 43 TC 17 Z9 20 U1 0 U2 3 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 MAY 1 PY 1998 VL 46 IS 8 BP 2881 EP 2894 DI 10.1016/S1359-6454(97)00441-2 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZP054 UT WOS:000073711900029 ER PT J AU Reed, WJ Mueller, RW AF Reed, WJ Mueller, RW TI Spiral fracture of the humerus in a ball thrower SO AMERICAN JOURNAL OF EMERGENCY MEDICINE LA English DT Article DE humerus fracture; throwing; stress fracture; pathologic fracture; arm pain AB Spiral fractures of the humerus in ball throwers are rare clinical entities that can be confused with pathologic fractures. These fractures have been reported in various throwing sports, arm wrestling, and hand grenade throwing, They most commonly occur in the distal third of the humerus in young, active individuals. They are often preceded by throwing arm pain, Neurologic sequelae are rare, Herein, a case is presented of spiral fracture of the humerus in a softball player, and the assessment and management of these fractures, as well as their etiologic contrast to stress and pathologic fractures, are reviewed. Copyright (C) 1998 by W.B. Saunders Company. C1 USN Hosp, Dept Aviat Med, Rota, Spain. RP Reed, WJ (reprint author), USN, Med Ctr, Dept Clin Res, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 18 TC 4 Z9 4 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 0735-6757 J9 AM J EMERG MED JI Am. J. Emerg. Med. PD MAY PY 1998 VL 16 IS 3 BP 306 EP 308 DI 10.1016/S0735-6757(98)90109-7 PG 3 WC Emergency Medicine SC Emergency Medicine GA ZM423 UT WOS:000073538700023 PM 9596440 ER PT J AU Dunlevy, TM Karakla, DW AF Dunlevy, TM Karakla, DW TI Uvulopalatopharyngoplasty: The Naval Medical Center, Portsmouth, experience SO AMERICAN JOURNAL OF OTOLARYNGOLOGY LA English DT Article ID OBSTRUCTIVE SLEEP-APNEA AB Purpose: To review the surgical results of uvulopalatopharyngoplasties (UPPP) performed at the Naval Medical Center, Portsmouth, VA, for the treatment of obstructive sleep apnea. The results will be evaluated comparing the recognized standard criteria with a proposed revised criteria. Materials and Methods: A retrospective review was completed of uvulopalatopharyngoplasties performed from January 1, 1994 to July 30, 1996. Preoperative polysomnography and apnea-related symptoms were compared with those recorded postoperatively. Results: With our new proposed criteria, an apnea-hypopnea index of less than 20 acid lowest oxygen saturation of greater than 85%, the success rate of UPPP was 49%. If patients with severe sleep apnea were excluded, the success rate rose to 69%. Conclusion: UPPP alone is an effective treatment for mild to moderately severe obstructive sleep apnea. However, it is not effective as the sole treatment for severe obstructive sleep apnea. This is a US government work. There are no restrictions on its use. C1 USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, Portsmouth, VA USA. RP Dunlevy, TM (reprint author), USN Hosp, Dept Otolaryngol Head & Neck Surg, 2080 Child Ave, Jacksonville, FL 32214 USA. NR 13 TC 3 Z9 3 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0196-0709 J9 AM J OTOLARYNG JI Am. J. Otolaryngol. PD MAY-JUN PY 1998 VL 19 IS 3 BP 174 EP 177 DI 10.1016/S0196-0709(98)90084-9 PG 4 WC Otorhinolaryngology SC Otorhinolaryngology GA ZN573 UT WOS:000073659400006 PM 9617929 ER PT J AU Buono, MJ Heaney, JH Canine, KM AF Buono, MJ Heaney, JH Canine, KM TI Acclimation to humid heat lowers resting core temperature SO AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY LA English DT Article DE heat storage; high wet-bulb temperature; temperature regulation; resting body temperature ID THERMOREGULATORY RESPONSES; MUSCLE METABOLISM; BLOOD-FLOW; EXERCISE; PERFORMANCE AB The purpose of this study was to test the hypothesis that a reduction in resting rectal temperature (T-re) is partially responsible for the attenuation in the rise of core temperature during heat exposure following acclimation to humid heat. Nine male volunteers completed 7 days of acclimation, performing 2 h of exercise per day in a hot, humid environment (35 degrees C, 75% relative humidity). Mean (+/-SD) ending T-re significantly (P < 0.05) decreased from 38.9 +/- 0.5 degrees C on day 2 to 38.3 +/- 0.4 degrees C on day 7. Likewise, mean (+/-SD) resting T-re significantly (P < 0.05) decreased from 37.0 +/- 0.3 to 36.7 +/- 0.4 degrees C. In fact, all nine men showed a decrease in resting T-re from day 1 to day 7, ranging from -0.1 to -0.5 degrees C. In addition, resting T-re and ending T-re were significantly correlated (r = 0.68). However, the mean increases in T-re tending T-re minus resting T-re) and heat storage that occurred on each of the 7 acclimation days were not significantly different. These results support the hypothesis that a reduction in resting T-re is partially responsible for the attenuation in ending T-re during heat exposure following short-term acclimation to humid heat. C1 San Diego State Univ, Dept Exercise & Nutr Sci, San Diego, CA 92182 USA. San Diego State Univ, Dept Biol, San Diego, CA 92182 USA. Naval Hlth Res Ctr, Appl Physiol Div, San Diego, CA 92186 USA. RP Buono, MJ (reprint author), San Diego State Univ, Dept Exercise & Nutr Sci, San Diego, CA 92182 USA. NR 24 TC 57 Z9 62 U1 0 U2 4 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0363-6119 J9 AM J PHYSIOL-REG I JI Am. J. Physiol.-Regul. Integr. Comp. Physiol. PD MAY PY 1998 VL 274 IS 5 BP R1295 EP R1299 PG 5 WC Physiology SC Physiology GA ZM189 UT WOS:000073513600012 PM 9644042 ER PT J AU Simmons, M Nelson, WM Wu, SJL Hayes, CG AF Simmons, M Nelson, WM Wu, SJL Hayes, CG TI Evaluation of the protective efficacy of a recombinant dengue envelope B domain fusion protein against dengue 2 virus infection in mice SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID MONOCLONAL-ANTIBODIES; STRUCTURAL PROTEINS; ANTIGENIC DETERMINANTS; ESCHERICHIA-COLI; GLYCOPROTEIN; ENCEPHALITIS; MEMBRANE; SURFACE; GENE AB A recombinant protein containing part of the dengue (DEN) 2 envelope protein was evaluated as a subunit immunogen for vaccination against DEN virus infection. A gene fragment encoding amino acids 298-400 (B domain) of the DEN-2 virus envelope was expressed as a fusion protein with the maltose binding protein (MBP) of Escherichia coli. This recombinant, DEN-2(B)/MBP, was purified and analyzed for its antigenicity, immunogenicity, and ability to protect mice against lethal challenge. The recombinant antigen reacted with a DEN-2 type-specific neutralizing monoclonal antibody (3H5), DEN-2 hyperimmune mouse ascitic fluid, and DEN-2 immune human sera. When administered to mice, DEN-2(B)/MBP elicited a DEN-2 virus neutralizing antibody response that conferred partial protection against challenge infection with a lethal dose of DEN-2 virus administered by intracranial inoculation. In addition, no replication of DEN-2 virus was detectable in the brains of the immunized mice as compared with control mice that were killed six days after challenge. Sera from immunized mice revealed no cross-neutralizing antibody to any of the other DEN serotypes in the plaque-reduction neutralization test. These findings warrant further studies with the DEN-2(B)/MBP antigen as a potential human vaccine candidate. An effective vaccine could prevent thousands of cases of illness and many deaths each year resulting from DEN virus infections. C1 USN, Med Res Inst, Dept Infect Dis, Bethesda, MD 20889 USA. RP Simmons, M (reprint author), USN, Med Res Inst, Dept Infect Dis, Code 4121,8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 35 TC 75 Z9 86 U1 0 U2 1 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 USA SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD MAY PY 1998 VL 58 IS 5 BP 655 EP 662 PG 8 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA ZN155 UT WOS:000073615400021 PM 9598457 ER PT J AU Mazin, II Fei, YW Downs, R Cohen, R AF Mazin, II Fei, YW Downs, R Cohen, R TI Possible polytypism in FeO at high pressures SO AMERICAN MINERALOGIST LA English DT Article ID BAND THEORY; WUSTITE; METALLIZATION; MANTLE; CORE; CAO; MNO; NIO AB Examination of X-ray diffraction intensities for FeO collected in situ at high pressure and high temperature reveals that the atomic arrangements of FeO in the hexagonal structure are not the same as those in the simple NiAs-type structure (B8) where Fe takes the place of Ni. The observed diffraction intensity can be explained by adding an anti-Bg component (where Fe takes the place of As). Substitution of Fe and O atoms for each other is crystallochemically unique. The exchange of Fe and O positions provides a critical measure of the change in chemical bonding. Our conclusion is consistent with the observed transition of FeO from an ionically bonded structure to a strongly covalent and metallic one. First-principles electronic structure computations using the linearized augmented plane wave (LAPW) method with the generalized gradient approximation (GGA) indicate that both B8 and anti-B8 should be antiferromagnetic, but only anti-B8 should be an insulator. The GGA and local density approximation (LDA) incorrectly compute anti-B8 as the ground state structure. C1 Carnegie Inst Washington, Geophys Lab, Washington, DC 20015 USA. Carnegie Inst Washington, Ctr High Pressure Res, Washington, DC 20015 USA. RP Mazin, II (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008; Fei, Yingwei/F-3709-2011 OI Fei, Yingwei/0000-0001-9955-5353 NR 25 TC 49 Z9 50 U1 1 U2 6 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1015 EIGHTEENTH ST, NW SUITE 601, WASHINGTON, DC 20036 USA SN 0003-004X J9 AM MINERAL JI Am. Miner. PD MAY-JUN PY 1998 VL 83 IS 5-6 BP 451 EP 457 PG 7 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA ZK140 UT WOS:000073289400005 ER PT J AU Horwitz, JS Chrisey, DB Stroud, RM Carter, AC Kim, J Chang, W Pond, JM Kirchoefer, SW Osofsky, MS Koller, D AF Horwitz, JS Chrisey, DB Stroud, RM Carter, AC Kim, J Chang, W Pond, JM Kirchoefer, SW Osofsky, MS Koller, D TI Pulsed laser deposition as a materials research tool SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 4th International Conference on Laser Ablation (COLA 97) CY JUL 21-25, 1997 CL MONTEREY BAY, CA DE pulsed laser deposition (PLD); high T(c) superconductors; ferroelectrics; colossal magneto resistance (CMR) ID FERROELECTRIC THIN-FILMS; DIELECTRIC-PROPERTIES; PRESSURE AB Pulsed laser deposition (PLD) is currently being used to deposit a variety of multicomponent electronic ceramic thin films as a materials research tool for the development of next generation electronic devices. Examples include YBa(2)Cu(3)O(7-delta)/ferromagnetic multilayers, ferroelectrics and rare earth doped manganite thin films. In YBa(2)Cu(3)O(7-delta)/ferromagnetic multilayers, the injection of spin-polarized electrons from the ferromagnetic material into the superconductor produces a local reduction in the superconducting order parameter. This effect is being used to develop MTS-based digital logic. The electric field effect in Sr(x)Ba((1-x))TiO(3) thin films is being used to develop tunable microwave circuits. A 4:1 change in the dielectric constant has been observed for fields less than or equal to 80 kV/cm. Microstructural defects associated with cation and anion vacancies have been observed in Sr(x)Ba((1-x))TiO(3) films. These defects have been correlated with dielectric loss and can be reduced by the use of a compensated targets and a post-deposition anneal of the deposited films. A large temperature coefficient of resistance (TCR) has been observed in rare earth doped manganite thin films. A TCR as large as similar to 30% has been observed for well annealed La(0.67)Ca(0.33)MnO(delta) thin films. These materials can be used to increase the sensitivity of uncooled IR focal plane arrays by more than an order of magnitude making them comparable to HgCdTe detectors. This paper presents the advances in thin film processing and the importance of PLD as a tool for research in the physics of thin films, materials science and the fabrication of devices based on electronic ceramics. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Washington, DC 20375 USA. RP Horwitz, JS (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Stroud, Rhonda/C-5503-2008; Osofsky, Michael/A-1050-2010 OI Stroud, Rhonda/0000-0001-5242-8015; NR 21 TC 14 Z9 17 U1 1 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD MAY PY 1998 VL 127 BP 507 EP 513 DI 10.1016/S0169-4332(97)00683-1 PG 7 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA ZP584 UT WOS:000073768100083 ER PT J AU Wu, C Burke, TJ AF Wu, C Burke, TJ TI Intelligent computer aided optimization on specific power of an OTEC Rankine power plant SO APPLIED THERMAL ENGINEERING LA English DT Article DE intelligent computer; ocean thermal energy conversion; optimization; power ID CYCLE AB Specific power, power per unit total heat exchanger surface area, of a heal engine is chosen to be the objective function in the design of an OTEC (Ocean Thermal Energy Conversion) Rankine power plant. An ICAI (Intelligent Computer Aided Instruction) computer software, CyclePad, with Refrigerant-12 as the working fluid operating between a warm ocean water heat source and a cold ocean water heat sink is used in the design process. Through manipulation of the boiler pressure and condenser pressure, the specific power of the OTEC plant is calculated and an upper bound is determined. This bound can direct the design of current and future OTEC heat engines to provide beneficial applications in industry. Published by Elsevier Science Ltd. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Wu, C (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. NR 10 TC 9 Z9 9 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-4311 J9 APPL THERM ENG JI Appl. Therm. Eng. PD MAY PY 1998 VL 18 IS 5 BP 295 EP 300 DI 10.1016/S1359-4311(97)00057-4 PG 6 WC Thermodynamics; Energy & Fuels; Engineering, Mechanical; Mechanics SC Thermodynamics; Energy & Fuels; Engineering; Mechanics GA ZB032 UT WOS:000072428000007 ER PT J AU Urban, SE Corbin, TE Wycoff, GL AF Urban, SE Corbin, TE Wycoff, GL TI The act reference catalog SO ASTRONOMICAL JOURNAL LA English DT Article DE astrometry; catalogs; reference systems; surveys AB The US Naval Observatory has completed the compilation of the ACT Reference Catalog, containing 988,758 stars covering the entire sky. The motivation behind the ACT was to provide accurate proper motions for the majority of the stars in the Tycho Catalogue. To do this, positions from new reductions of the Astrographic Catalogue (AC 2000) were combined with those of the Tycho Catalogue. The large epoch span between the two catalogs yields proper motions about an order of magnitude more accurate than those found in the Tycho Catalogue. The astrometric data contained in the ACT Reference Catalog include positions and proper motions and their corresponding errors. These are on the Hipparcos system (ICRS) for epoch J2000.0. Photometric and variability data from Tycho are included. In addition, crossreferences to the Tycho, AC 2000, Bonner Durchmusterung (BD), Cordoba Durchmusterung (CD), Cape Durchmusterung (CPD), Henry Draper (HD), and Hipparcos catalogs are given. The ACT is now available at the international data centers and by contacting the authors via electronic mail. C1 USN Observ, Washington, DC 20392 USA. RP Urban, SE (reprint author), USN Observ, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. NR 17 TC 126 Z9 126 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 MAY PY 1998 VL 115 IS 5 BP 2161 EP 2166 DI 10.1086/300344 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZQ213 UT WOS:000073834100036 ER PT J AU Grandi, P Haardt, F Ghisellini, G Grove, EJ Maraschi, L Urry, CM AF Grandi, P Haardt, F Ghisellini, G Grove, EJ Maraschi, L Urry, CM TI High-energy break and reflection features in the Seyfert galaxy MCG +8-11-11 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, individual (MCG +8-11-11); galaxies, Seyfert; radiation mechanisms, nonthermal; X-rays, galaxies ID GAMMA-RAY EMISSION; X-RAY; ACCRETION DISKS; THERMAL PLASMAS; COMPTONIZATION; MCG-8-11-11; VARIABILITY; NGC-4151; CORONAE; SPECTRA AB We present the results from ASCA and OSSE simultaneous observations of the Seyfert 1.5 galaxy MCG +8-11-11 performed in 1995 August-September. The ASCA observations, split into two pointings of similar to 10 ks each, indicate a modest flux increase (similar to 20%) in 3 days, possibly correlated to a softening of the 0.6-9 keV spectrum. The spectrum obtained combining data from both the observations is well described by a hard power law (Gamma similar to 1.64 +/- 0.03) absorbed by a column density slightly larger than the Galactic value. An iron line at 6.4 keV of EW similar to 400 eV is also required by the data. The simultaneous OSSE data are characterized by a much softer power law with photon index Gamma = 3.0(-0.8)(+0.9), strongly suggesting the presence of a spectral break in the hard X-ray/soft gamma-ray band. In order to better investigate the complex hard X-ray spectrum of this source, a total spectrum has been produced by summing over all the observations of MCG +8-11-11 performed by OSSE so far. A joint fit to the complete OSSE data sets and our ASCA data clearly shows an exponential cutoff of the power law at similar to 300 keV (e-folding energy), as well as a quite strong reflection component. MCG fg-ll-ll is then one of the few Seyfert galaxies for which a spectral break in the underlying continuum is detected unambiguously, fitting well in the X-ray/gamma-ray description of co-added spectra of Seyfert galaxies. Though the break could be due to downscattering of X-rays on cold e(+)e(-) pairs in a nonthermal plasma, the inferred low compactness of this source favors instead thermal or quasi-thermal electron Comptonization in a structured corona as the leading process of high-energy radiation production. C1 Ist Astrofis Spaziale, I-00044 Frascati, Italy. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Osservatorio Astron Merate, I-20121 Milan, Italy. USN, EO Hulburt Ctr Space Res, Res Lab, Washington, DC 20375 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Grandi, P (reprint author), Ist Astrofis Spaziale, Via E Fermi 21, I-00044 Frascati, Italy. RI Urry, Claudia/G-7381-2011 OI Urry, Claudia/0000-0002-0745-9792 NR 41 TC 14 Z9 14 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 MAY 1 PY 1998 VL 498 IS 1 BP 220 EP 225 DI 10.1086/305557 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZM044 UT WOS:000073499100020 ER PT J AU Emslie, AG Mariska, JT Montgomery, MM Newton, EK AF Emslie, AG Mariska, JT Montgomery, MM Newton, EK TI Hydrodynamic modeling of the response of the solar atmosphere to bombardment by a beam of nonthermal protons SO ASTROPHYSICAL JOURNAL LA English DT Article DE hydrodynamics; Sun, atmosphere; Sun, corona; Sun, flares; Sun, particle emission; Sun, X-rays, gamma rays ID IMPULSIVE PHASE; ALPHA EMISSION; HEATED MODELS; H-ALPHA; FLARES; DIAGNOSTICS; ABUNDANCES; MOMENTUM; TARGET AB Using a one-dimensional time-dependent numerical hydrodynamic model, we examine the response of the solar atmosphere to heating by a beam of energetic protons with a characteristic energy near 1 MeV. At these energies, the coronal portion of the flaring loop must be treated as a "warm" target, while the chromospheric portion behaves as a "cold" target. This results in a more uniform heating in the coronal portions of the loop than is the case with energetic electrons, leading to smaller pressure gradients and lower plasma upflow velocities. Such lower velocities would appear at first to be more consistent with observed soft X-ray line profiles. However, velocity differential emission measures computed at various times in the calculation show that heating by energetic protons does not satisfactorily reproduce the atmospheric response as inferred from such observations. C1 Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Dynet Inc, Huntsville, AL 35806 USA. RP Emslie, AG (reprint author), Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. NR 29 TC 5 Z9 5 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 MAY 1 PY 1998 VL 498 IS 1 BP 441 EP 447 DI 10.1086/305551 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZM044 UT WOS:000073499100043 ER PT J AU Watkins, SM Welch, L Whitley, P Forster, E AF Watkins, SM Welch, L Whitley, P Forster, E TI The design of arm pressure covers to alleviate pain in high G maneuvers SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article AB Hypothesis: Arm pain has been noted especially when increased coverage anti-G suits are worn in combination with PBG (pressure breathing during G) in high G centrifuge test runs. Arm pain has forced the termination of test runs and has the potential to cause a serious decrement in a pilot's ability to function effectively during high-G flight. Based on the theory that arm pain is caused by fluid pooling in the arm, four new pressure cover systems for the arm were designed and tested. Methods: Seven test subjects wore each design in a series of runs in a dynamic flight simulator (DFS). Subjects experienced both gradual and rapid onset rate runs with G levels ranging from +3.0 G to +9.0 G. Data were collected on the maximum G's achieved, pain location, and pain intensity. Subjective responses on the comfort and function of each design and overall arm cover design preferences were also obtained via a questionnaire. Results: Analysis of the DFS data, using a two-factor ANOVA (subjects, designs), revealed that each of the new designs provided significantly better protection from arm pain than the control condition (no protection) and that each of the designs significantly improved the maximum G level attained during rapid onset acceleration in the range of +1G. Conclusion: No positive correlation was found between subject ranking of the four new design concepts at the conclusion of the study in terms of the pain reduction they provided and the pain levels reported during DFS testing. C1 Cornell Univ, Ithaca, NY 14850 USA. M Technol Inc, Huntingdon Valley, PA USA. USN, Air Warfare Ctr, Human Syst Integrat Div, Warminster, PA USA. RP Watkins, SM (reprint author), Cornell Univ, 325 Van Rensselaer Hall, Ithaca, NY 14850 USA. NR 8 TC 7 Z9 7 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 MAY PY 1998 VL 69 IS 5 BP 461 EP 467 PG 7 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA ZK121 UT WOS:000073287400004 PM 9591615 ER PT J AU Hudson, SJ AF Hudson, SJ TI Eye injuries from laser exposure: A review SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID DAMAGE AB Lasers pose a significant threat to vision in modern military operations. Anti-personnel lasers have been designed that can cause intentional blindness in large numbers of personnel. Although the use of blinding laser weapons during combat has been prohibited by international legislation, research and development of these weapons have not been prohibited, and significant controversy remains. Unintentional blinding can also result from other types of lasers used on the battlefield, such as range-finders and anti-material lasers. Lasers that are capable of producing blindness operate within specific wavelength parameters and include visible and near infrared lasers. Patients who suffer from laser eye injuries usually complain of flash blindness, followed by transient or permanent visual loss. Laser retinal damage should be suspected in any patient with visual complaints in an operational setting. The treatment for laser retinal injuries is extremely limited, and prevention is essential. Improved protective eyeware and other countermeasures to laser eye injury are necessary as long as the threat remains. C1 USN, Med Corps, Naval Air Stn, Whidbey Isl, WA USA. RP Hudson, SJ (reprint author), 1349 SW Looking Glass Loop, Oak Harbor, WA 98277 USA. NR 19 TC 11 Z9 14 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 MAY PY 1998 VL 69 IS 5 BP 519 EP 524 PG 6 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA ZK121 UT WOS:000073287400015 PM 9591626 ER PT J AU Mate, BR Gisiner, R Mobley, J AF Mate, BR Gisiner, R Mobley, J TI Local and migratory movements of Hawaiian humpback whales tracked by satellite telemetry SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID MEGAPTERA-NOVAEANGLIAE; NORTH PACIFIC AB We examined inter-island movements and offshore migrations of six humpback whales (Megaptera novaeangliae) tagged during March and April 1995 with satellite-monitored radio tags off Kaua'i, Hawai'i. The tags transmitted 0.5-17 days ((x) over bar = 8.5 +/- 2.7 days) and produced 1-66 locations that met our screening criteria. Total travel distances per individual ranged from 30 to 1860 km. After screening criteria were applied,satellite-acquired locations ranged from 1.8 to 3.9/day for individuals (group average 2.7/day). One adult traveled 250 km to O'ahu in 4 days. Another visited Penguin Bank and five islands (820 km) in 10 days, suggesting faster inter-island movement than had been previously thought. Three whales traveled independent, parallel courses toward the upper Gulf of Alaska on north-northeast headings. A female with a calf was the fastest: 670 km in 4.5 days (150 km/day). Two whales traveled for 14.7 and 17 days, an average speed of 110 km/day (4.5 km/h). A 4200-km migration to the upper Gulf of Alaska at that speed would take 39 days. If the fastest whale's speed was maintained on a straight course, the entire migration could be accomplished in as little time as 28 days. Based on the two longest tracks, the first third of the migration route is within 1 degrees of magnetic north. These data represent the first route and travel speeds for humpbacks migrating from Hawai'i toward Alaska. C1 Oregon State Univ, Hatfield Marine Sci Ctr, Newport, OR 97365 USA. Off Naval Res, Arlington, VA 22217 USA. Univ Hawaii, Pearl City, HI 96782 USA. RP Mate, BR (reprint author), Oregon State Univ, Hatfield Marine Sci Ctr, Newport, OR 97365 USA. NR 14 TC 58 Z9 62 U1 3 U2 20 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD MAY PY 1998 VL 76 IS 5 BP 863 EP 868 DI 10.1139/cjz-76-5-863 PG 6 WC Zoology SC Zoology GA 127GU UT WOS:000076343200010 ER PT J AU Moss, RB Wallace, MR Lanza, P Giermakowska, W Jensen, FC Theofan, G Chamberlin, C Richieri, SP Carlo, DJ AF Moss, RB Wallace, MR Lanza, P Giermakowska, W Jensen, FC Theofan, G Chamberlin, C Richieri, SP Carlo, DJ TI In vitro p24 antigen-stimulated lymphocyte proliferation and beta-chemokine production in human immunodeficiency virus type 1 (HIV-1)-seropositive subjects after immunization with an inactivated gp120-depleted HIV-1 immunogen (Remune) SO CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY LA English DT Article ID T-CELLS; RESPONSES; AIDS AB We examined the effect of immune stimulation by a human immunodeficiency virus type 1 (HIV-1) immunogen (Remune) compared to a non-MN vaccine (influenza) on HIV-l-specific immune responses in HIV-1-seropositive subjects, HIV-1 p24 antigen-stimulated lymphocyte proliferation was not augmented after immunization with the influenza vaccine. In contrast, subjects increased their lymphocyte proliferative responses to p24 antigen after one immunization with HIV-1 immunogen (Remune) (gp120-depleted inactivated HIV-1 ire incomplete Freund's adjuvant), Furthermore, p24 antigen-stimulated beta-chemokine production (RANTES, MIP-1 alpha, MIP-1 beta) was also augmented after immunization with the HIV-1 immunogen brat not influenza vaccine. Taken together, these results suggest that in this cohort, HN-specific immune responses to p24 antigen can be augmented after immunization with an HN-I immunogen. The ability to upregulate immune responses to the more conserved core proteins may have important implications in the development of immunotherapeutic interventions for HIV-1 infection. C1 Immune Response Corp, Carlsbad, CA 92008 USA. USN, Med Ctr, Div Infect Dis, San Diego, CA 92152 USA. RP Moss, RB (reprint author), Immune Response Corp, 5935 Darwin Ct, Carlsbad, CA 92008 USA. NR 23 TC 25 Z9 25 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 MAY PY 1998 VL 5 IS 3 BP 308 EP 312 PG 5 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZL785 UT WOS:000073471300008 PM 9605982 ER PT J AU Lenz, HJ Danenberg, KD Leichman, CG Florentine, B Johnston, PG Groshen, S Zhou, LY Xiong, YP Danenberg, PV Leichman, LP AF Lenz, HJ Danenberg, KD Leichman, CG Florentine, B Johnston, PG Groshen, S Zhou, LY Xiong, YP Danenberg, PV Leichman, LP TI p53 and thymidylate synthase expression in untreated stage II colon cancer: Associations with recurrence, survival, and site SO CLINICAL CANCER RESEARCH LA English DT Article ID FLUOROURACIL PLUS LEVAMISOLE; NEGATIVE BREAST-CANCER; PROGNOSTIC-SIGNIFICANCE; PROTEIN EXPRESSION; COLORECTAL-CANCER; ADJUVANT THERAPY; BLADDER-CANCER; GENE; ADENOCARCINOMA; OVEREXPRESSION AB We initiated a retrospective study to determine whether p53 status and thymidylate synthase (TS) protein expression in primary colon tumors influence recurrence and survival for patients with stage II colon cancer. Tumor specimens from 45 consecutive untreated patients with stage II colon cancer were examined for p53 and TS protein expression using immunohistochemistry. The median follow-up was 5.1 years. Eighteen patients had left-sided tumors, and 27 had right-sided tumors. Fourteen of 45 patients (31%) developed recurrence. p53 overexpression was detected in the tumors of 18 patients (40%); 10 patients (55%) with p53 overexpression recurred; and 4 of 27 (15%) without evidence of p53 overexpression recurred (P = 0.002), High TS expression was detected in the tumors of 16 patients (36%): 8 patients (50%) with high TS expression recurred, and 6 patients (21%) with low TS expression recurred (P = 0.027), Patients with p53 overexpression had a significantly poorer survival than did those patients without p53 overexpression (P < 0.001). High TS expression was associated with poor survival (P = 0.004), p53 overexpression and high TS expression were significantly associated with left-sided tumors (P = 0.003 and P = 0.022), Thirteen of 16 patients (81%) with high TS expression also overexpressed p53, and 24 of 29 patients (81%) with low TS expression did not manifest p53 overexpression (P < 0.001), p53 and TS expression in primary stage LI colon cancer are associated and appear to influence recurrence and survival. In this pilot study, left-sided tumors demonstrate significantly more p53 overexpression and significantly higher TS expression than do right-sided tumors, which may explain the significantly poorer survival for patients with left-sided tumors. C1 Univ So Calif, Norris Comprehens Canc Ctr, Canc Res Lab 218, Sch Med,Div Med Oncol, Los Angeles, CA 90033 USA. Univ So Calif, Norris Comprehens Canc Ctr, Sch Med, Dept Pathol, Los Angeles, CA 90033 USA. Univ So Calif, Norris Comprehens Canc Ctr, Sch Med, Dept Biochem & Mol Biol, Los Angeles, CA 90033 USA. Univ So Calif, Norris Comprehens Canc Ctr, Sch Med, Dept Prevent Med, Los Angeles, CA 90033 USA. USN, NCI, Med Oncol Branch, Bethesda, MD 20089 USA. RP Lenz, HJ (reprint author), Univ So Calif, Norris Comprehens Canc Ctr, Canc Res Lab 218, Sch Med,Div Med Oncol, 1303 N Mission Rd, Los Angeles, CA 90033 USA. EM lenz@hsc.usc.edu FU NCI NIH HHS [CA-60108, CA-70802, P30CA14089] NR 42 TC 124 Z9 126 U1 0 U2 0 PU AMER ASSOC CANCER RESEARCH PI BIRMINGHAM PA PO BOX 11806, BIRMINGHAM, AL 35202 USA SN 1078-0432 J9 CLIN CANCER RES JI Clin. Cancer Res. PD MAY PY 1998 VL 4 IS 5 BP 1227 EP 1234 PG 8 WC Oncology SC Oncology GA ZL982 UT WOS:000073493000018 PM 9607581 ER PT J AU Owens, MT AF Owens, MT TI High-Tech War SO COMMENTARY LA English DT Letter C1 USN, War Coll, Newport, RI 02840 USA. RP Owens, MT (reprint author), USN, War Coll, Newport, RI 02840 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER JEWISH COMMITTEE PI NEW YORK PA 165 E 56TH ST, NEW YORK, NY 10022 USA SN 0010-2601 J9 COMMENTARY JI Commentary PD MAY PY 1998 VL 105 IS 5 BP 13 EP 14 PG 2 WC Political Science; Social Issues SC Government & Law; Social Issues GA ZJ592 UT WOS:000073232200007 ER PT J AU Caccia, M Casalino, G Cristi, R Veruggio, G AF Caccia, M Casalino, G Cristi, R Veruggio, G TI Acoustic motion estimation and control for an unmanned underwater vehicle in a structured environment SO CONTROL ENGINEERING PRACTICE LA English DT Article DE underwater vehicles; navigation; guidance and control systems; motion-control systems; extended Kalman filter; identification; acoustics AB The problem of identification and navigation, guidance and control in unmanned underwater vehicles (UUVs) is addressed in this paper. A task-function-based guidance system and an acoustic motion estimation module have been integrated with a conventional UUV autopilot within a two-layered hierarchical architecture for closed-loop control. Basic techniques to estimate the robot dynamics using the sensors mounted on the vehicle have been investigated. The proposed identification techniques and navigation, guidance and control (NGC) system have been tested on Roby2, a UUV developed at the Istituto Automazione Navale of the Italian C.N.R. The experimental set-up, as well as the modalities and results, are discussed. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 CNR, Inst Automaz Navale, I-16149 Genoa, Italy. Univ Genoa, Dipartimento Informat Sistemist & Telemat, Genoa, Italy. USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Caccia, M (reprint author), CNR, Inst Automaz Navale, Via De Marini 6, I-16149 Genoa, Italy. RI Veruggio, Gianmarco/B-9405-2013; OI Caccia, Massimo/0000-0002-4482-4541 NR 28 TC 14 Z9 15 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0661 J9 CONTROL ENG PRACT JI Control Eng. Practice PD MAY PY 1998 VL 6 IS 5 BP 661 EP 670 DI 10.1016/S0967-0661(98)00057-4 PG 10 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA 137YV UT WOS:000076945400010 ER PT J AU Sridhar, S AF Sridhar, S TI Decision support using the Intranet SO DECISION SUPPORT SYSTEMS LA English DT Article DE Intranet; decision support; World Wide Web; Internet; distributed computing ID SYSTEM AB The Intranet is rapidly leading to new ways of using, sharing and managing information in many organizations. This paper explores the role of Intranet from a new perspective-as a mechanism for supporting decision-making. This paper is divided into two parts. The first part of the paper uses the well-known data-dialog-model framework of decision support systems. It explores how an Intranet can be useful for rapid and flexible access to information required for decision-making. The second part of the paper presents a taxonomy of major types of Intranet-based decision support with illustrative examples. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Postgrad Sch, Dept Syst Management, Monterey, CA 93943 USA. RP Sridhar, S (reprint author), USN, Postgrad Sch, Dept Syst Management, Code SM-SR, Monterey, CA 93943 USA. EM sridhar@nps.navy.mil NR 31 TC 33 Z9 34 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9236 J9 DECIS SUPPORT SYST JI Decis. Support Syst. PD MAY PY 1998 VL 23 IS 1 BP 19 EP 28 DI 10.1016/S0167-9236(98)00033-5 PG 10 WC Computer Science, Artificial Intelligence; Computer Science, Information Systems; Operations Research & Management Science SC Computer Science; Operations Research & Management Science GA 115EH UT WOS:000075650200003 ER PT J AU Shen, CY Evans, TE AF Shen, CY Evans, TE TI Inertial instability of large Rossby number horizontal shear flows in a thin homogeneous layer SO DYNAMICS OF ATMOSPHERES AND OCEANS LA English DT Article DE Rossby number; finite-amplitude evolution; rotating plane; inertial instability; shear-flow instability AB A horizontal shear flow having a Rossby number, Ro, greater than unity on a rotating plane can become unstable when its shear value is less than -f, the Coriolis frequency. In this paper, this instability is investigated for an O(10 km) submesoscale, sinusoidal shear flow in a thin homogeneous fluid layer as in an oceanic mixed layer or a shallow sea. The most unstable mode is shown by a linear analysis to occur in a narrow localized region centered around the maximum anticyclonic current shear. However, nonlinear numerical calculations show that the instability can grow to encompass both unstable and stable regions of the current. A consequence of this finite-amplitude evolution is the formation of surface convergence/shear fronts. The possibility that inertial instability mechanism is a source of some surface convergence/shear features seen in remote sensing images of the sea surface is discussed. A comparison is made with the shear-flow instability that can occur concurrently in a sinusoidal shear current, and inertial instability is shown to be the dominant instability mechanism in the immediate range above Ro = 2. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Shen, CY (reprint author), USN, Res Lab, Code 7250, Washington, DC 20375 USA. NR 12 TC 10 Z9 10 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0265 J9 DYNAM ATMOS OCEANS JI Dyn. Atmos. Oceans PD MAY PY 1998 VL 26 IS 4 BP 185 EP 208 DI 10.1016/S0377-0265(98)00042-6 PG 24 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Oceanography SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Oceanography GA ZX983 UT WOS:000074575000001 ER PT J AU Spiesberger, JL Hurlburt, HE Johnson, M Keller, M Meyers, S O'Brien, J AF Spiesberger, JL Hurlburt, HE Johnson, M Keller, M Meyers, S O'Brien, J TI Acoustic thermometry data compared with two ocean models: the importance of Rossby waves and ENSO in modifying the ocean interior SO DYNAMICS OF ATMOSPHERES AND OCEANS LA English DT Article DE Rossby waves; ENSO; ocean ID NORTH-ATLANTIC OCEAN; CURRENT SYSTEM; PACIFIC-OCEAN; VARIABILITY; TOMOGRAPHY; TEMPERATURE; TOPOGRAPHY; SEA AB An interpretation is made of interannual changes in acoustic travel time between Oahu and seven receivers at distances of 3000-4000 km, Measurements were made in late 1983, and over two 5-month intervals between 1987 and 1989, Previous publications demonstrated that these changes stem from variations in temperature. Two hydrodynamic ocean models are used to identify plausible oceanic features that could cause these variations. They are from the Naval Research Laboratory and the Florida State University at (1/8)degrees and (1/6)degrees resolution, respectively, and are forced with different interannual wind sets for more than a decade. Modelled El Nino's and La Nina's generate poleward travelling Kelvin waves on the eastern boundary of the Pacific, These excite Rossby waves that propagate westward at mid-latitudes. Rossby waves are the dominant model features which affect the modelled acoustic travel times, and hence section-averaged temperatures in the eastern North Pacific. These waves yield travel times whose standard deviations and rates of changes are similar to the measurements. In the observations, some sections separated by less than 500 km exhibit trends in heat content with opposite signs, Similar variability can be explained with modelled Rossby waves. Model wavelengths less than 500 km, eddies, and seasonal cycles induced by seasonal winds yield travel times that are two orders of magnitude too small to account for the data. Published by Elsevier Science B.V. C1 Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. Penn State Univ, Appl Res Lab, University Pk, PA 16802 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Univ Alaska Fairbanks, Inst Marine Sci, Fairbanks, AK USA. Florida State Univ, Ctr Ocean Atmosphere Predict Studies, Tallahassee, FL 32306 USA. RP Spiesberger, JL (reprint author), Penn State Univ, Dept Meteorol, 503 Walker Bldg, University Pk, PA 16802 USA. OI meyers, steven/0000-0003-1592-9050 NR 55 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0265 J9 DYNAM ATMOS OCEANS JI Dyn. Atmos. Oceans PD MAY PY 1998 VL 26 IS 4 BP 209 EP 240 DI 10.1016/S0377-0265(97)00044-4 PG 32 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Oceanography SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Oceanography GA ZX983 UT WOS:000074575000002 ER PT J AU Wu, C Chen, LG Sun, FR AF Wu, C Chen, LG Sun, FR TI Effect of heat transfer law on finite-time exergoeconomic performance of Carnot heat pump SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE heat pump; performance; effect; heat transfer AB The operation of a Carnot heat pump is viewed as a production process with exergy as its output. The short-run economic optimization ol the endoreversible heat pump is performed in this paper. The profit of the heat pump is taken as the optimization objective function. Using the method of finite-time exergoeconomic analysis, which emphasizes the compromise optimization between economics (profit) and the utilization factor of energy (Coefficient of Performance, COP) for finite-time (endoreversible) thermodynamic cycles, this paper derives the relation between optimal profit and COP of an endoreversible Carnot heat pump based on a relatively general heat transfer law: q proportional to Delta(T-n). The COP bound at the maximum profit is also obtained. The results obtained involve those for three common heat transfer laws: Newton's Law (n = 1), the linear phenomenological law in irreversible thermodynamics (n = -1), and the radiative heat law (n = 4). Published by Elsevier Science Ltd. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. RP Wu, C (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. NR 23 TC 25 Z9 29 U1 1 U2 5 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 MAY PY 1998 VL 39 IS 7 BP 579 EP 588 DI 10.1016/S0196-8904(97)10012-7 PG 10 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA YW546 UT WOS:000071947200004 ER PT J AU Chen, LG Wu, C Sun, FR Cao, S AF Chen, LG Wu, C Sun, FR Cao, S TI Heat transfer effects on the net work output and efficiency characteristics for an air-standard Otto cycle SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE Otto cycle; heat transfer; net work output; efficiency ID INTERNAL-COMBUSTION ENGINES; FINITE-TIME; THERMODYNAMICS; POWER AB Finite-time thermodynamic analysis of an air-standard Otto cycle is performed in this paper. The relation between net work output and efficiency of the cycle is derived. The maximum net work output and the corresponding efficiency bound of the cycle with heat transfer considerations are also found. Detailed numerical examples are given. The result obtained herein provides a guide to the performance evaluation and improvement for practical Otto engines. Published by Elsevier Science Ltd. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. RP Wu, C (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. NR 11 TC 65 Z9 76 U1 0 U2 6 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 MAY PY 1998 VL 39 IS 7 BP 643 EP 648 DI 10.1016/S0196-8904(97)10003-6 PG 6 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA YW546 UT WOS:000071947200010 ER PT J AU Bailey, JL Jones, WW Tatem, PA Forney, GP AF Bailey, JL Jones, WW Tatem, PA Forney, GP TI Development of an algorithm to predict vertical heat transfer through ceiling/floor conduction SO FIRE TECHNOLOGY LA English DT Article DE fire model; zone model; heat transfer; model validation AB This paper describes a new algorithm of the Consolidated Fire Growth and Smoke Transport (CFAST) fire model and compares the results with data from real-scale fire tests conducted aboard the ex-USS Shadwell, the U.S. Navy's Research and Development Damage Control Platform. The new phenomenon modeled in this work is the conduction of heat in the vertical direction. The Shadwell tests chosen for validation purposes were part of the Internal Ship Conflagration Control (ISCC) Program. The work focuses on four compartments of the ship that were vertically aligned. The temperatures of the compartments and the decks between them were compared with model predictions. The predictions were very close to the experimental results for ail compartments, although the temperature rise in the topmost compartment was barely above ambient. C1 USN, Res Lab, Washington, DC 20375 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Bailey, JL (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 12 TC 1 Z9 1 U1 0 U2 2 PU NATIONAL FIRE PROTECTION ASSOC PI QUINCY PA ONE BATTERYMARCH PK, QUINCY, MA 02269 USA SN 0015-2684 J9 FIRE TECHNOL JI Fire Technol. PD MAY-JUN PY 1998 VL 34 IS 2 BP 139 EP 155 DI 10.1023/A:1015377402737 PG 17 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA ZW094 UT WOS:000074373400004 ER PT J AU Hagen, RA Gohl, K Gersonde, R Kuhn, G Volker, D Kodagali, VN AF Hagen, RA Gohl, K Gersonde, R Kuhn, G Volker, D Kodagali, VN TI A geophysical survey of the De Gerlache seamounts: preliminary results SO GEO-MARINE LETTERS LA English DT Article ID TECTONIC HISTORY; PACIFIC; BATHYMETRY AB The De Gerlache Seamounts actually consist of two medium-sized guyots, with summits at depths of 350-600 m. Acoustic profiler data show no significant sediment on these guyots. Alkaline basalts dredged from the summit of the eastern guyot yield K/Ar ages between 20.1 +/- 1.0 and 23.2 +/- 1.2 Ma. Basement ridges and sediment-filled troughs between the guyots are associated with the prominent gravity anomaly extending north from the Antarctic margin. This structure possibly played a role in the guyot formation, however, the question of how the De Gerlache Seamounts are related to this gravity anomaly remains uncertain. C1 USN, Res Lab, Washington, DC 20375 USA. Macquarie Univ, Sch Earth Sci, Sydney, NSW 2109, Australia. Alfred Wegener Inst Polar & Marine Res, D-27515 Bremerhaven, Germany. Univ Bremen, Fachbereich Geowissensch, D-28359 Bremen, Germany. Natl Inst Oceanog, Dona Paula, Goa, India. RP Hagen, RA (reprint author), USN, Res Lab, Code 7420,4555 Overlook Ave SW, Washington, DC 20375 USA. OI Kuhn, Gerhard/0000-0001-6069-7485; Gohl, Karsten/0000-0002-9558-2116 NR 18 TC 8 Z9 8 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0276-0460 J9 GEO-MAR LETT JI Geo-Mar. Lett. PD MAY PY 1998 VL 18 IS 1 BP 19 EP 25 DI 10.1007/s003670050047 PG 7 WC Geosciences, Multidisciplinary; Oceanography SC Geology; Oceanography GA ZR247 UT WOS:000073955000003 ER PT J AU Zyda, M Darken, RP AF Zyda, M Darken, RP TI The Naval Postgraduate School's Moves curriculum SO IEEE COMPUTER GRAPHICS AND APPLICATIONS LA English DT Editorial Material C1 USN, Dept Comp Sci, Postgrad Sch, Monterey, CA 93943 USA. RP Zyda, M (reprint author), USN, Dept Comp Sci, Postgrad Sch, Code CS Zk,Spanagel Hall 252, Monterey, CA 93943 USA. NR 6 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 0272-1716 J9 IEEE COMPUT GRAPH JI IEEE Comput. Graph. Appl. PD MAY-JUN PY 1998 VL 18 IS 3 BP 8 EP 11 DI 10.1109/38.674965 PG 4 WC Computer Science, Software Engineering SC Computer Science GA ZJ721 UT WOS:000073245800005 ER PT J AU Rowe, NC Galvin, TP AF Rowe, NC Galvin, TP TI An authoring system for intelligent procedural-skill tutors SO IEEE INTELLIGENT SYSTEMS & THEIR APPLICATIONS LA English DT Article C1 USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. US Central Command, Def Informat Syst Agcy Field Off, Eskan Village, Saudi Arabia. RP Rowe, NC (reprint author), USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93943 USA. NR 10 TC 12 Z9 12 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 0885-9000 J9 IEEE INTELL SYST APP JI IEEE Intell. Syst. Appl. PD MAY-JUN PY 1998 VL 13 IS 3 BP 61 EP 69 DI 10.1109/5254.683211 PG 9 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA ZT049 UT WOS:000074042500013 ER PT J AU Darken, R AF Darken, R TI Breaking the Mosaic mold SO IEEE INTERNET COMPUTING LA English DT Editorial Material C1 USN, Postgrad Sch, Monterey, CA 93940 USA. RP Darken, R (reprint author), USN, Postgrad Sch, Monterey, CA 93940 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1089-7801 J9 IEEE INTERNET COMPUT JI IEEE Internet Comput. PD MAY-JUN PY 1998 VL 2 IS 3 BP 97 EP 99 DI 10.1109/MIC.1998.683807 PG 3 WC Computer Science, Software Engineering SC Computer Science GA 111XR UT WOS:000075464400023 ER PT J AU Reed, MG Syverson, PF Goldschlag, DM AF Reed, MG Syverson, PF Goldschlag, DM TI Anonymous connections and onion routing SO IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS LA English DT Article DE anonymity; communications; Internet; privacy; security; traffic analysis AB Onion routing is an infrastructure for private communication over a public network, It provides anonymous connections that are strongly resistant to bath eavesdropping and traffic analysis. Onion routing's anonymous connections are bidirectional, near real-time, and can be used anywhere a socket connection can be used, Any identifying information must be in the dam stream carried over ale anonymous connection, An onion is a data structure that is treated as the destination address by onion routers; thus, it is used to establish an anonymous connection, Onions themselves appear different to each onion router as well as to network observers, The same goes for data carried over the connections they establish. Proxy-aware applications, such as web browsers and e-mail clients, require no modification to use onion routing, and do so through a series of proxies a prototype Onion routing network is running between our lab and other sites. This paper describes anonymous connections and their implementation using onion routing, This paper also describes several application proxies for onion routing, as well as configurations of onion routing networks. C1 USN, Res Lab, Ctr High Assurance Comp Syst, Washington, DC 20375 USA. Divx, Herndon, VA 22071 USA. RP Reed, MG (reprint author), USN, Res Lab, Ctr High Assurance Comp Syst, Washington, DC 20375 USA. EM reed@itd.nrl.navy.mil; syverson@itd.nrl.navy.mil; david.goldschlag@divx.com NR 21 TC 301 Z9 332 U1 1 U2 23 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0733-8716 J9 IEEE J SEL AREA COMM JI IEEE J. Sel. Areas Commun. PD MAY PY 1998 VL 16 IS 4 BP 482 EP 494 DI 10.1109/49.668972 PG 13 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA ZL242 UT WOS:000073413000005 ER PT J AU Bewley, WW Felix, CL Vurgaftman, I Aifer, EH Meyer, JR Goldberg, L Lindle, JR Chow, PH Selvig, E AF Bewley, WW Felix, CL Vurgaftman, I Aifer, EH Meyer, JR Goldberg, L Lindle, JR Chow, PH Selvig, E TI Continuous-wave mid-infrared VCSEL's SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE continuous-wave (CW) lasers; distributed Bragg reflector (DBR) lasers; mid-infrared lasers; optical pumping; quantum-well lasers; surface-emitting lasers ID LASERS AB We report the continuous-wave operation of an optically pumped mid-infrared (mid-IR) vertical-cavity surface-emitting laser (VCSEL). The active region consisting of type-II antimonide quantum wells with a "W" configuration occupies a cavity formed by a semiconductor bottom mirror and dielectric top mirror. The emission wavelength of 2.9 mu m is nearly independent of temperature (d-lambda/d-gamma approximate to 0.09 nm/K) compared to type-II edge-emitters and the multimode linewidth is narrow (2.9 nm). At T = 78 K, the threshold pump intensity is approximate to 940 W/cm(2), the peak output power from a 50-mu m spot is 45 mW, and the differential power conversion efficiency is 4.5%. Lasing is observed up to T = 160 K. C1 USN, Res Lab, Washington, DC 20375 USA. Hughes Res Lab, Malibu, CA 90265 USA. RP Bewley, WW (reprint author), USN, Res Lab, Code 5600, Washington, DC 20375 USA. RI Selvig, Espen/B-5122-2008; Lindle, James/A-9426-2009 NR 10 TC 26 Z9 27 U1 0 U2 10 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD MAY PY 1998 VL 10 IS 5 BP 660 EP 662 DI 10.1109/68.669235 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZH777 UT WOS:000073146600010 ER PT J AU Matthews, PJ Frankel, MY Esman, RD AF Matthews, PJ Frankel, MY Esman, RD TI A wide-band fiber-optic true-time-steered array receiver capable of multiple independent simultaneous beams SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE antenna array feeds; optical fiber delay lines; optical fiber applications; optical fiber dispersion; phased-array radar; phased arrays AB A wide-band fiber-optic true-time-delay array receiver capable of receiving multiple independent beams simultaneously is demonstrated for the first time. The receiver is based on a dispersive prism technique and exhibits squint-free +/-60 degrees azimuthal steering of two simultaneous beams with no observable beam squint over a microwave component-limited bandwidth of 6-18 GHz. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Matthews, PJ (reprint author), USN, Res Lab, Div Opt Sci, Code 5672, Washington, DC 20375 USA. NR 5 TC 37 Z9 37 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 MAY PY 1998 VL 10 IS 5 BP 722 EP 724 DI 10.1109/68.669401 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZH777 UT WOS:000073146600031 ER PT J AU Cobb, MA Foley, H Wilson, R Chung, MY Shaw, KB AF Cobb, MA Foley, H Wilson, R Chung, MY Shaw, KB TI An OO database migrates to the Web SO IEEE SOFTWARE LA English DT Article AB Traditional databases can be restructured to take advantage of OO methods. Java's advent has enhanced OO's benefits by providing a way to run applications across varying platforms. To take advantage of these trends, the authors first converted a relational database to the OO paradigm, then migrated it to the Web. Here they describe the procedures and technologies they used to accomplish the migration. C1 USN, Res Lab, Charting & Geodesy Branch, Stennis Space Ctr, MS 39529 USA. Univ So Mississippi, Hattiesburg, MS 39406 USA. RP Shaw, KB (reprint author), USN, Res Lab, Charting & Geodesy Branch, Stennis Space Ctr, MS 39529 USA. NR 10 TC 7 Z9 7 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0740-7459 J9 IEEE SOFTWARE JI IEEE Softw. PD MAY-JUN PY 1998 VL 15 IS 3 BP 22 EP + DI 10.1109/52.676716 PG 10 WC Computer Science, Software Engineering SC Computer Science GA ZN234 UT WOS:000073623300011 ER PT J AU Simhadri, KK Iyengar, SS Holyer, RJ Lybanon, M Zachary, JM AF Simhadri, KK Iyengar, SS Holyer, RJ Lybanon, M Zachary, JM TI Wavelet-based feature extraction from oceanographic images SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE edge detection; feature extraction; image processing; multiresolution; noise suppression; wavelet transform AB Features in satellite images of the oceans often have weak edges. These images also have a significant amount of noise, which is either due to the clouds or atmospheric humidity. The presence of noise compounds the problems associated with the detection of features, as the use of any traditional noise removal technique will also result in the removal of weak edges. Recently, there have been rapid advances in image processing as a result of the development of the mathematical theory of wavelet transforms. This theory led to multifrequency channel decomposition of images, which further led to the evolution of important algorithms for the reconstruction of images at various resolutions from the decompositions. The possibility of analyzing images at various resolutions can be useful not only in the suppression of noise, but also in the detection of fine features and their classification. This paper presents a new computational scheme based on multiresolution decomposition for extracting the features of interest from the oceanographic images by suppressing the noise. The multiresolution analysis from the median presented by Starck-Murtagh-Bijaoui [4], [5] is used for the noise suppression. C1 Louisiana State Univ, Dept Comp Sci, Robot Res Lab, Baton Rouge, LA 70803 USA. USN, Res Lab, Remote Sensing Div, Stennis Space Ctr, MS 39529 USA. RP Simhadri, KK (reprint author), Louisiana State Univ, Dept Comp Sci, Robot Res Lab, Baton Rouge, LA 70803 USA. EM iyengar@bit.csc.lsu.edu NR 21 TC 39 Z9 41 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 1998 VL 36 IS 3 BP 767 EP 778 DI 10.1109/36.673670 PG 12 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA ZM593 UT WOS:000073555700008 ER PT J AU Cho, EC Iyengar, SS Seetharaman, G Holyer, RJ Lybanon, M AF Cho, EC Iyengar, SS Seetharaman, G Holyer, RJ Lybanon, M TI Velocity vectors for features of sequential oceanographic images SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE features; oceanographic images; simplicial approximations; triangulation; velocity vectors ID SURFACE VELOCITIES; ZONE AB This paper investigates a fundamental problem of determining the position, orientation, and velocity field of the Gulf Stream in time-varying imagery, We propose an approximation method to characterize the deformation of these image motions for the purpose of estimating the velocity field of these images. The technique is focused on the interpretation of the change in the extracted features of the Gulf Stream. The underlying technique employs a triangulation of the region by a simplicial approximation of the velocity field on each triangle, A generalized computational framework, an outline of the mathematical foundation, and an implementation are presented in this paper. C1 Kent State Univ, Frankfort, KY 40601 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Univ SW Louisiana, Lafayette, LA 70501 USA. USN, Res Lab, Bay St Louis, MS 39529 USA. RP Cho, EC (reprint author), Kent State Univ, Frankfort, KY 40601 USA. EM iyengar@bit.csc.lsu.edu NR 17 TC 2 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 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 1998 VL 36 IS 3 BP 985 EP 998 DI 10.1109/36.673689 PG 14 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA ZM593 UT WOS:000073555700027 ER PT J AU Miao, X Azimi-Sadjadi, MR Tian, B Dubey, AC Witherspoon, NH AF Miao, X Azimi-Sadjadi, MR Tian, B Dubey, AC Witherspoon, NH TI Detection of mines and minelike targets using principal component and neural-network methods SO IEEE TRANSACTIONS ON NEURAL NETWORKS LA English DT Article DE landmine detection; neural networks; pattern recognition; principal component analysis ID BURIED DIELECTRIC ANOMALIES; MULTISPECTRAL IMAGERY; LAND MINES; CLASSIFICATION; PERFORMANCE AB This paper introduces a new system for real-time detection and classification of arbitrarily scattered surface-laid mines from multispectral imagery data of a minefield. The system consists of six channels which use various neural-network structures for feature extraction, detection, and classification of targets in six different optical bands ranging from near UV to near IR, A single-layer autoassociative network trained using the recursive least square (RLS) learning rule was employed in each channel to perform feature extraction. Based upon the extracted features, two different neural-network architectures were used and their performance was compared against the standard maximum likelihood (ML) classification scheme. The outputs of the detector/classifier network in all the channels were fused together in a final decision-making system. Two different final decision making schemes using the majority voting and weighted combination based on consensual theory were considered. Simulations were performed on real data for six bands and on several images in order to account for the variations in size, shape, and contrast of the targets and also the signal-to-clutter ratio, The overall results showed the promise of the proposed system for detection and classification of mines and minelike tagets. C1 Colorado State Univ, Dept Elect Engn, Ft Collins, CO 80523 USA. USN, Warfare Syst Ctr, Dahlgren Div, Coastal Syst Stn, Panama City, FL 32407 USA. RP Miao, X (reprint author), Colorado State Univ, Dept Elect Engn, Ft Collins, CO 80523 USA. NR 26 TC 23 Z9 23 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 1045-9227 J9 IEEE T NEURAL NETWOR JI IEEE Trans. Neural Netw. PD MAY PY 1998 VL 9 IS 3 BP 454 EP 463 DI 10.1109/72.668887 PG 10 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA ZL842 UT WOS:000073477600010 PM 18252469 ER PT J AU Powell, DJ Hayward, G Ting, RY AF Powell, DJ Hayward, G Ting, RY TI Unidimensional modeling of multi-layered piezoelectric transducer structures SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article AB Multi-layered transducer structures offer the potential of improved performance in terms of increased transmit sensitivity, greater bandwidth, and enhanced reception characteristics. Unfortunately, the successful design of such devices is often difficult, owing to the complex interaction between the active piezoelectric layers and passive intermediate interface layers. Furthermore, in many practical applications, the loading effects imposed by the electrical drive circuitry often limit the performance improvements that may be physically realized. This paper describes the development of a comprehensive, unidimensional modeling approach. This model may be employed to facilitate the analysis and subsequent optimization of laminated transducer assemblies. The devices currently under consideration include both piezoceramic and piezopolymer configurations, as well as alternative piezocomposite designs. The effects of varying bondline thickness and the introduction of passive interface layers are examined, as is the influence of the electrical load circuitry on overall system response. The ability to accurately predict the response of stacked piezoelectric structures is demonstrated through extensive comparison of experimental and theoretical responses. This paper concludes by highlighting the important role that modeling plays in the design, fabrication, and optimization of complex multi-layered transducer assemblies. C1 Weidlinger Associates Inc, Los Altos, CA 94022 USA. Univ Strathclyde, Dept Elect & Elect Engn, Glasgow G1 1XW, Lanark, Scotland. USN, Res Lab, Underwater Sound Reference Detachment, Orlando, FL 32856 USA. RP Powell, DJ (reprint author), Weidlinger Associates Inc, Los Altos, CA 94022 USA. NR 7 TC 30 Z9 32 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 0885-3010 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD MAY PY 1998 VL 45 IS 3 BP 667 EP 677 DI 10.1109/58.677611 PG 11 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA ZQ882 UT WOS:000073912500015 PM 18244218 ER PT J AU Romano, AJ Shirron, JJ Bucaro, JA AF Romano, AJ Shirron, JJ Bucaro, JA TI On the noninvasive determination of material parameters from a knowledge of elastic displacements: Theory and numerical simulation SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article ID SUPERCONVERGENT PATCH RECOVERY; POST-PROCESSING APPROACH; ACOUSTIC STRAIN WAVES; FINITE-ELEMENT METHOD; MODULI AB In this paper, we present a formulation and numerical simulation for the noninvasive determination of the material parameter ratios (i.e., the Lame parameters divided by density) of an isotropic, inhomogenous elastic medium subject to time harmonic vibration. Given a knowledge of the displacements throughout the medium, a novel implementation of a variational formulation is used to determine the ratios lambda/rho and mu/rho. A theoretical formulation is presented and validated using numerical data obtained from a finite element method. The results indicate that the method may be applied locally within an inhomogenous medium, and that the corresponding material parameters can be recovered to a high degree of accuracy. In addition, the method does not appear to be subject to the typical wavelength constraints of previous methods. C1 USN, Res Lab, Washington, DC 20375 USA. RP Romano, AJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 23 TC 54 Z9 54 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-3010 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD MAY PY 1998 VL 45 IS 3 BP 751 EP 759 DI 10.1109/58.677725 PG 9 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA ZQ882 UT WOS:000073912500023 PM 18244226 ER PT J AU Bultman, JD Chen, SL Schloman, WW AF Bultman, JD Chen, SL Schloman, WW TI Anti-termitic efficacy of the resin and rubber in fractionator overheads from a guayule extraction process SO INDUSTRIAL CROPS AND PRODUCTS LA English DT Article DE guayule; Parthenium argentatum; cis-1,4-polyisoprene; resin; rubber; termites; termiticides AB Antitermitic properties were evaluated for a mixture of resin and rubber obtained by solvent extraction of guayule. Pine (Pinus strobus L.) sapwood was impregnated with fractionator overheads consisting of resin and low-molecular-weight rubber. The impregnated wood was exposed for 71 months at two sites in the Panama rain forest and for 67 months at a site in the Arizona desert. None of the treated wood sustained any termite damage at either site, whereas untreated baitwood was routinely destroyed. The impregnant mixture acted as a termite antifeedant rather than a repellant. Almost no loss of resin or rubber was sustained by specimens exposed in Arizona, whereas significant losses occurred at both sites in Panama. Environmental factors, including microbiological activity, may have contributed to the loss of both resin and rubber in the rain forest environment. Enough impregnant did remain in the wood to protect it from termite attack throughout the exposure period. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Akron, Maurice Morton Inst Polymer Sci, Akron, OH 44325 USA. RP Bultman, JD (reprint author), USN, Res Lab, Code 6127, Washington, DC 20375 USA. NR 24 TC 11 Z9 11 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-6690 J9 IND CROP PROD JI Ind. Crop. Prod. PD MAY PY 1998 VL 8 IS 2 BP 133 EP 143 DI 10.1016/S0926-6690(97)10018-8 PG 11 WC Agricultural Engineering; Agronomy SC Agriculture GA ZM591 UT WOS:000073555500006 ER PT J AU Carter, BR Watson, DW Freund, RF Keith, E Mirabile, F Siegel, HJ AF Carter, BR Watson, DW Freund, RF Keith, E Mirabile, F Siegel, HJ TI Generational scheduling for dynamic task management in heterogeneous computing systems SO INFORMATION SCIENCES LA English DT Article; Proceedings Paper CT 1996 International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 96) CY AUG 09-11, 1996 CL SUNNYVALE, CALIFORNIA SP Comp Sci Res Educ & Applicat Tech, Alta Technol Corp, Pacific Sierra Res Corp, Transtech Parallel Syst Corp, Morgan Kaufmann Publ Inc AB Heterogeneous computing (HC) is the coordinated use of different types of machines, networks, and interfaces in order to maximize performance and/or cost effectiveness. In recent years, research related to HC has addressed one of its most fundamental challenges: how to develop a schedule of tasks on a set of heterogeneous hosts that minimizes the time required to execute the given tasks. The development of such a schedule is made difficult by diverse processing abilities among the hosts, data and precedence dependencies among the tasks, and other factors. This paper outlines a straightforward approach to solving this problem, termed generational?al scheduling (GS).;GS provides fast, efficient matching of tasks to hosts and requires little overhead to implement. This study introduces the GS approach and illustrates its effectiveness in terms of the time to determine schedules and the quality of schedules produced. A communication-inclusive extension of GS is presented to illustrate how GS can be used when the overhead of transferring data produced be some tasks and consumed by others is significant. Finally, to illustrate the effectiveness of GS in a real-world environment, a series of experiments are presented using GS in the SmartNet scheduling framework, developed at US Navy's facility at the Naval Command, Control, and Ocean Surveillance Center in San Diego, California. (C) 1998 Elsevier Science Inc. All rights reserved. C1 IBM Corp, IMAD 9541, Austin, TX 78758 USA. Utah State Univ, Dept Comp Sci, Logan, UT 84322 USA. USN, Command Control & Ocean Surveillance Ctr, San Diego, CA 92152 USA. Sci Applicat Int Corp, San Diego, CA 92110 USA. Purdue Univ, Sch Elect & Comp Engn, W Lafayette, IN 47907 USA. RP Carter, BR (reprint author), IBM Corp, IMAD 9541, 11400 Burnet Rd, Austin, TX 78758 USA. NR 15 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0020-0255 J9 INFORM SCIENCES JI Inf. Sci. PD MAY PY 1998 VL 106 IS 3-4 BP 219 EP 236 DI 10.1016/S0020-0255(97)10012-3 PG 18 WC Computer Science, Information Systems SC Computer Science GA ZV793 UT WOS:000074341800003 ER PT J AU Geyer, WP Smith, EC Keller, JA AF Geyer, WP Smith, EC Keller, JA TI Aeroelastic analysis of transient blade dynamics during shipboard engage/disengage operations SO JOURNAL OF AIRCRAFT LA English DT Article ID HELICOPTER; BEHAVIOR; MODEL AB An analysis has been developed to predict transient aeroelastic rotor response during shipboard engage/disengage sequences. The blade is modeled as an elastic beam undergoing deflections in flap and torsion. The blade equations of motion are formulated using Hamilton's principle and they are spatially discretized using the finite element method. The discretized blade equations of motion are integrated for a specified rotor speed run-up or run-down profile. Blade element theory is used to calculate quasisteady or unsteady aerodynamic loads in linear and nonlinear regimes. Three different simple wind-gust distributions are modeled. Basic ship-roll motion characteristics are also included in the shipboard airwake environment. An H-46 rotor system model is developed and shows excellent correlation with experimental static tip deflection and blade natural frequency data; Parametric studies are conducted-to systematically investigate the effects of collective and cyclic pitch control settings, droop stop angle, and ship motion on blade response. These studies indicate that collective and cyclic control inputs have a moderate effect on maximum negative tip deflections. Torsion is shown not to be required for rotorcraft with small amounts of pitch-flap coupling. Unsteady aerodynamics is shown only to be important to the blade response-at high wind speeds for spatially varying gusts, A flap damper is incorporated and is effective in reducing tip deflections if the flap stop angle is increased. C1 USN, Air Warfare Ctr, Div Aircraft, Test Evaluat Engn Dept, Patuxent River, MD 20670 USA. Penn State Univ, Dept Aerosp Engn, University Pk, PA 16802 USA. RP Geyer, WP (reprint author), USN, Air Warfare Ctr, Div Aircraft, Test Evaluat Engn Dept, Patuxent River, MD 20670 USA. NR 15 TC 8 Z9 12 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 MAY-JUN PY 1998 VL 35 IS 3 BP 445 EP 453 DI 10.2514/2.2317 PG 9 WC Engineering, Aerospace SC Engineering GA ZQ723 UT WOS:000073896600013 ER PT J AU Sitch, PK Jungnickel, G Kaukonen, M Porezag, D Frauenheim, T Pederson, MR Jackson, KA AF Sitch, PK Jungnickel, G Kaukonen, M Porezag, D Frauenheim, T Pederson, MR Jackson, KA TI A study of substitutional nitrogen impurities in chemical vapor deposited diamond SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CVD DIAMOND; AMORPHOUS-CARBON; SURFACES; DEFECTS; ENERGY AB The behavior of substitutional N impurities in chemical vapor deposited diamond is examined theoretically in order to explain recent channeling experiments indicating a dominant onsite incorporation of N. The calculations are based on a combination of density-functional methods at various levels of approximation applied to supercell and cluster models. Neutral charge N impurities in the presence of highly defective carbon regions, such as dangling bonds, strained bonds, and partially developed rr bonds are studied. We find a perfectly general argument concerning the position of the substitutional N atom in relation to the position of the Fermi level, E-f: if E-f lies above the A(1) level associated with the onsite substitutional N atom, off-site motion in the (111) direction is observed. Conversely, when E-f falls below A(1), N doping charge is transferred to the available deeper lying states. Suitable receptor states include surface dangling bonds, surface reconstruction rr bonds, and bulk defects states such as grain boundaries and vacancies. (C) 1998 American Institute of Physics. C1 TU Chemnitz, D-09107 Chemnitz, Germany. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RP Sitch, PK (reprint author), TU Chemnitz, D-09107 Chemnitz, Germany. EM p.sitch@physik.tu-chemnitz.de RI Kaukonen, Markus/M-7232-2013; Frauenheim, Thomas/C-5653-2015 OI Kaukonen, Markus/0000-0003-2835-7469; Frauenheim, Thomas/0000-0002-3073-0616 NR 28 TC 11 Z9 11 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1998 VL 83 IS 9 BP 4642 EP 4646 DI 10.1063/1.367249 PG 5 WC Physics, Applied SC Physics GA ZM292 UT WOS:000073523900013 ER PT J AU Edelstein, AS Bussmann, KM Turner, DC Chopra, HD AF Edelstein, AS Bussmann, KM Turner, DC Chopra, HD TI Interlayer coupling in Co/Cu/permalloy/Cu multilayers SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INTERPLAY; LAYERS AB The interlayer coupling, domain structure, and microstructure of ion beam sputtered multilayers, were investigated by magnetization, optical microscopy using magnetic colloids, small and wide angle x-ray scattering, and atomic force microscopy measurements. The study focused on multilayers that were composed of ten repeats of Co(1.5 nm)/Cu(t(Cu))/permalloy(2.6 nm)/Cu(t(Cu)) with t(Cu)=2.6 and 5.0 nm. The top surface rms roughness of the multilayers was 0.31 and 0.96 nm for samples with t(Cu)=2.6 and 5.0 nm, respectively. The maximum peak to peak roughness in a 1 mu m(2) scan was 3.0 and 8.9 nm for samples with t(Cu)=2.6 and 5.0 nm, respectively. The lateral feature size was 30-40 nm and 70 nm for samples with t(Cu)=2.6 and 5.0 nm, respectively. The multilayers with t(Cu)=2.6 had sharper, flatter interfaces than those with t(Cu)=5.0 nm. Magnetization measurements and the domain structure at room temperature showed that when t(Cu)=2.6 nm the Co and permalloy layers were ferromagnetically coupled, while if t(Cu)=5.0 nm, the Co and permalloy layers were largely uncoupled. Twin walls present for t(Cu)=2.6 nm clearly indicated locked-in domains of the ferromagnetically coupled Co and permalloy layers; for t(Cu)=5.0 nm, such coupled wall structures were almost nonexistent. Modeling the magnetization, it is estimated that the ferromagnetic coupling only has to be greater than 0.0047 mJ/m(2) for the Co and permalloy layer magnetizations to be nearly parallel at all field values. Since not much coupling is needed, the coupling in the samples with t(Cu)=2.6 nm could be due to the magnetostatic coupling which exists even in perfectly flat films or to the magnetostatic coupling of surface magnetic dipoles created by roughness. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Washington, DC 20375 USA. Dartmouth Coll, Thayer Sch Engn, Hanover, NH 03755 USA. RP Edelstein, AS (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 22 TC 10 Z9 11 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 MAY 1 PY 1998 VL 83 IS 9 BP 4848 EP 4854 DI 10.1063/1.367282 PG 7 WC Physics, Applied SC Physics GA ZM292 UT WOS:000073523900046 ER PT J AU Morrill, JS Bucsela, EJ Pasko, VP Berg, SL Heavner, MJ Moudry, DR Benesch, WM Wescott, EM Sentman, DD AF Morrill, JS Bucsela, EJ Pasko, VP Berg, SL Heavner, MJ Moudry, DR Benesch, WM Wescott, EM Sentman, DD TI Time resolved N-2 triplet state vibrational populations and emissions associated with red sprites SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article ID ELECTROSTATIC THUNDERCLOUD FIELDS; RUNAWAY AIR-BREAKDOWN; INTERSYSTEM COLLISIONAL TRANSFER; ENERGY-POOLING REACTIONS; GAMMA-RAY FLASHES; ELECTROMAGNETIC PULSES; EINSTEIN COEFFICIENTS; LOWER IONOSPHERE; BAND SYSTEMS; EXCITATION AB The results of a quasi-electrostatic electron heating model were combined with a time dependent N-2 vibrational level population model to simulate the spectral distributions and absolute intensities observed in red sprites. The results include both N-2 excited state vibrational level populations and time profiles of excited electronic state emission. Due to the long atmospheric paths associated with red sprite observations, atmospheric attenuation has a strong impact on the observed spectrum. We present model results showing the effect of atmospheric attenuation as a function of wavelength for various conditions relevant to sprite observations. in addition, our model results estimate the variation in the relative intensities of a number of specific Nz emissions in sprites (1PG, 2PG, and VK) in response to changes in observational geometry. A recent sprite spectrum, measured from the Wyoming Infrared Observatory (WIRO) on Jelm Mountain, during July, 1996, has been analyzed and includes N-2 IPG bands down to v' = 1. In addition to N-2 1PG, our analysis of this spectrum indicates the presence of spectral features which are attributable to N-2(+) Meinel emission. However, due to the low intensity in the observed spectrum and experimental uncertainties, the presence of the N-2(+)(A(2)II(u)) should be considered preliminary. The importance of both the populations of the lower levels of the N-2((BIIg)-I-3) and the N-2((BIIg)-I-3)/N-2(+)(A(2)II(g)) population ratio in the diagnosis of the electron energies present in red sprites is discussed. While the current spectral analysis yields a vibrational distribution of the N-2((BIIy)-I-3) which requires an average electron energy of only 1-2 eV, model results do indicate that the populations of the lower levels of the N-2((BIIg)-I-3) will increase with increases in the electron energy primarily due to cascade. Considering the importance of the populations of the lower vibrational levels, we are beginning to analyze additional sprite spectra, measured at higher resolution, which contain further information on the population of B(v = 1). (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Stanford Univ, Star Lab, Stanford, CA 94305 USA. Computat Phys Inc, Fairfax, VA USA. Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. Univ Alaska, Inst Geophys, Fairbanks, AK USA. Raytheon STX, Lanham, MD USA. RP Morrill, JS (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. EM morrill@cronus.nrl.navy.mil RI Pasko, Victor/S-6024-2016 NR 81 TC 56 Z9 56 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD MAY-JUN PY 1998 VL 60 IS 7-9 BP 811 EP 829 DI 10.1016/S1364-6826(98)00031-5 PG 19 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 124QP UT WOS:000076193500016 ER PT J AU Rowland, HL AF Rowland, HL TI Theories and simulations of elves, sprites and blue jets SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article ID ELECTROSTATIC THUNDERCLOUD FIELDS; TRANSIONOSPHERIC PULSE PAIRS; RUNAWAY AIR BREAKDOWN; GAMMA-RAY FLASHES; LOWER IONOSPHERE; ELECTROMAGNETIC PULSES; ELECTRICAL ENVIRONMENT; OPTICAL FLASHES; IONIZATION; THUNDERSTORMS AB This review considers the different models that have been developed to explain a class of phenomena that occur above lightning storms. These phenomena have been named elves, red sprites and blue jets. The elves appear between 90 and 70 km altitude and extend over several 100 km horizontally. They are visible for less than 0.1 ms. Red sprites cover a range of altitudes from 80 to 55 km with narrow tendrils extending below 55 km; Horizontally they are 20-30 km wide. Their visible lifetime is from a few to some tens of ms. Blue jets propagate from cloud tops (15 km) to an altitude of 40 km with a velocity of 100 km/s which gives a lifetime of 300 ms. In all of the models, the energy source is the electric fields associated with the lightning-the quasistatic fields due to the original charge distribution, the electromagnetic pulse due to the propagation of the return stroke or the quasistatic fields due to the charge redistribution by the currents. There are two different models to explain the heating of the neutral atmosphere by these electric fields. These models accelerate either the ambient thermal electrons (< eV) or high-energy, cosmic-ray-generated MeV electrons. These electrons in turn collisionally heat the neutrals and produce the heating, ionization and optical emissions. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. RP Rowland, HL (reprint author), USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. NR 47 TC 64 Z9 68 U1 4 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD MAY-JUN PY 1998 VL 60 IS 7-9 BP 831 EP 844 DI 10.1016/S1364-6826(98)00034-0 PG 14 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 124QP UT WOS:000076193500017 ER PT J AU Durkin, DP Cole, KA Copper, CL AF Durkin, DP Cole, KA Copper, CL TI Capillary electrophoretic determination of carboxyhemoglobin concentrations in postmortem blood samples SO JOURNAL OF CAPILLARY ELECTROPHORESIS LA English DT Article DE capillary electrophoresis; blood; hemoglobin; heme; carbon monoxide AB The use of capillary electrophoresis (CE) as an alternative to existing methods of quantitation of carbon monoxide (CO) in hemoglobin from postmortem blood samples is presented. The isolation of heme (the portion of the hemoglobin molecule in which CO binding takes place) from hemoglobin is described. Reduced (containing no gas molecules) heme and CO-heme isolated from hemoglobin standards were successfully separated using CE. Heme and CO-heme were also isolated from blood samples of accident victims and analyzed using CE. A quantifiable difference in the CO-heme signals from blood samples containing fatal and nonfatal levels of CO was observed.. C1 USN Acad, Annapolis, MD 21402 USA. USAF, Inst Pathol, Rockville, MD USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU I S C TECHNICAL PUBLICATIONS, INC PI SHELTON PA 30 CONTROLS DR, BOX 828, SHELTON, CT 06484-0828 USA SN 1079-5383 J9 J CAPILLARY ELECTROP JI J. Capillary Electrophor. PD MAY-AUG PY 1998 VL 5 IS 3-4 BP 129 EP 132 PG 4 WC Biochemistry & Molecular Biology; Electrochemistry SC Biochemistry & Molecular Biology; Electrochemistry GA 276TG UT WOS:000084893000006 PM 10797877 ER PT J AU Froimowitz, M George, C AF Froimowitz, M George, C TI Conformational analysis and a crystal structure of bupropion, an antidepressant with dopamine reuptake blocking activity SO JOURNAL OF CHEMICAL INFORMATION AND COMPUTER SCIENCES LA English DT Article ID DEFICIT HYPERACTIVITY DISORDER; COCAINE; BINDING; METHYLPHENIDATE; ANALOGS; SITES; INHIBITION; BLOCKERS; CFT AB A conformational analysis has been performed on the antidepressant bupropion using the MM3-92 program. In addition, the structure of the compound in the crystal state was obtained. There is good agreement between the computed global minimum and the structure observed by crystallography. The three-dimensional structure of the preferred conformer of bupropion is consistent with the three-dimensional structures of other dopamine reuptake blockers such as cocaine, CFT, and methylphenidate. C1 PharmEco Labs, Lexington, MA 02173 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Froimowitz, M (reprint author), PharmEco Labs, 128 Spring St, Lexington, MA 02173 USA. FU NIDA NIH HHS [DA 09045, N01DA-4-8313, N01DA-7-8083] NR 22 TC 12 Z9 12 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0095-2338 J9 J CHEM INF COMP SCI JI J. Chem. Inf. Comput. Sci. PD MAY-JUN PY 1998 VL 38 IS 3 BP 506 EP 510 DI 10.1021/ci980401m PG 5 WC Chemistry, Multidisciplinary; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications SC Chemistry; Computer Science GA ZP543 UT WOS:000073764000023 PM 9611786 ER PT J AU Luscombe, JH Luban, M Borsa, F AF Luscombe, JH Luban, M Borsa, F TI Classical Heisenberg model of magnetic molecular rings clusters: Accurate approximants for correlation functions and susceptibility SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SYSTEMS AB We show that the measured magnetic susceptibility of molecular ring clusters can be accurately reproduced, for all but low temperatures T, by a classical Heisenberg model of N identical spins S on a ring that interact with isotropic nearest-neighbor interactions. While exact expressions for the two-spin correlation function, C-N(n,T), and the zero-held magnetic susceptibility, chi(N)(T), are known for the classical Heisenberg ring, their evaluation involves summing infinite series of modified spherical Bessel functions. By contrast, the formula C-N(n,T)=(u(n)+u(N-n))/(1+u(N)), where u(K)=cothK-K-1 is the Langevin function and K=JS(S+1)/(k(B)T) is the nearest-neighbor dimensionless coupling constant, provides an excellent approximation if N greater than or equal to 6 for the regime \K\<3. This choice of approximant combines the expected exponential decay of correlations for increasing yet small values of n, with the cyclic boundary condition for a finite ring, C-N(n,T)=C-N(N-n,T), By way of illustration, we show that, for T>50 K, the associated approximant for the susceptibility derived from the approximate correlation function is virtually indistinguishable from both the exact theoretical susceptibility and the experimental data for the "ferric wheel" molecular cluster ([Fe(OCH3)(2)(O2CCH2Cl)](10)), which contains N=10 interacting Fe3+ ions, each of spin S=5/2, that are symmetrically positioned in a nearly planar ring. (C) 1998 American Institute of Physics. C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Univ Pavia, Dept Phys, I-27100 Pavia, Italy. RP Luscombe, JH (reprint author), USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. NR 14 TC 17 Z9 17 U1 0 U2 1 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 MAY 1 PY 1998 VL 108 IS 17 BP 7266 EP 7273 DI 10.1063/1.476144 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZK384 UT WOS:000073315200025 ER PT J AU Robinson, PJ Maddalozzo, D Simonson, L Breslin, S AF Robinson, PJ Maddalozzo, D Simonson, L Breslin, S TI Effect of electric toothbrushes on subgingival microflora of periodontitis patients. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USN, Dent Res Inst, Great Lakes, IL USA. Northwestern Univ, Chicago, IL 60611 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PD MAY PY 1998 VL 77 IS 5 BP 1237 EP 1237 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA ZL730 UT WOS:000073464700900 ER PT J AU Yale, GE Agrawal, BN AF Yale, GE Agrawal, BN TI Lyapunov controller for cooperative space manipulators SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID SATELLITE AB The cooperative control of multiple manipulators attached to the same base as they reposition a common payload is discussed. The theory is easily applied to inertially based problems, as well as space-based free-floating platforms. The system equations of motion are developed, as well as a Lyapunov-based controller that ensures stability. The closed chain aspect of the problem reduces the system's degrees of freedom resulting in more actuators than degrees of freedom. This actuator redundancy is used to minimize a weighted norm of the actuator torques. A polynomial reference trajectory describes the path the payload wilt follow. The disturbance torque transmitted to the spacecraft centerbody by the motion of the manipulators is reduced by altering the order of the reference trajectory polynomial and its coefficients. Results from a two-dimensional, dual-arm configuration are included. Compared to the Lyapunov point controller alone, the addition of a fifth-order polynomial reference trajectory leads to superior performance in terms of actuator torque magnitudes, spacecraft centerbody attitude control, and payload repositioning accuracy and time. An eighth-order polynomial reference trajectory results in only small improvement over the fifth-order case. C1 USAF Acad, Dept Astron, Colorado Springs, CO 80840 USA. USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93940 USA. RP Yale, GE (reprint author), USAF Acad, Dept Astron, Colorado Springs, CO 80840 USA. NR 12 TC 11 Z9 15 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 MAY-JUN PY 1998 VL 21 IS 3 BP 477 EP 484 DI 10.2514/2.4261 PG 8 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA ZN665 UT WOS:000073669400017 ER PT J AU Roselle, DC Seaver, M Eversole, JD AF Roselle, DC Seaver, M Eversole, JD TI Changes in intrinsic fluorescence during the production of viable but nonculturable Escherichia coli SO JOURNAL OF INDUSTRIAL MICROBIOLOGY & BIOTECHNOLOGY LA English DT Article DE intrinsic fluorescence spectroscopy; viable but nonculturable bacteria; VBNC bacteria; Escherichia coli ID BACTERIA AB The potential of intrinsic fluorescence spectroscopy to detect and differentiate viable but nonculturable bacteria in the presence of culturable bacteria was explored, Escherichia coli cells, starved for 210 days in nutrient-free normal saline, show new fluorescence emissions near 400 and 440 nm, and reduced emission near 340 nm. C1 USN, Res Lab, Washington, DC 20375 USA. RP Seaver, M (reprint author), USN, Res Lab, Code 5610, Washington, DC 20375 USA. NR 8 TC 4 Z9 4 U1 1 U2 6 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 1367-5435 J9 J IND MICROBIOL BIOT JI J. Ind. Microbiol. Biotechnol. PD MAY PY 1998 VL 20 IS 5 BP 265 EP 267 DI 10.1038/sj.jim.2900500 PG 3 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 107FF UT WOS:000075196000002 ER PT J AU Frankel, MY Esman, RD AF Frankel, MY Esman, RD TI Optical single-sideband suppressed-carrier modulator for wide-band signal processing SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article DE microwave signal processing; modulator; single-sideband; suppressed-carrier ID FREQUENCY AB We develop and demonstrate a technique for implementing a wide-band optical single-sideband suppressed-carrier modulator. The technique relies on a dual-electrode traveling wave modulator for sideband suppression and a Sagnac fiber-loop interferometer for carrier suppression, The implementation uses all commercially available components and demonstrates >40 dB optical carrier suppression, and as much as 60 dB unwanted signal sideband rejection across a 6-20 GHz microwave frequency range. The modulator is used to demonstrate broad-band spectral shifting and inversion across the 3-18 GHz frequency range. C1 USN, Div Opt Sci, Res Lab, Washington, DC 20375 USA. RP Frankel, MY (reprint author), USN, Div Opt Sci, Res Lab, Code 5672, Washington, DC 20375 USA. NR 12 TC 55 Z9 55 U1 0 U2 5 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 MAY PY 1998 VL 16 IS 5 BP 859 EP 863 DI 10.1109/50.669019 PG 5 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA ZK809 UT WOS:000073365900016 ER PT J AU Suits, BH Garroway, AN Miller, JB AF Suits, BH Garroway, AN Miller, JB TI Super-Q detection of transient magnetic resonance signals SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article AB The signal-to-noise ratio (SNR) improvements with increasing detection coil quality factor, Q, are examined for the detection of known magnetic resonance signals in noise. It is found that in the absence of amplifier noise, SNR continues to increase with increasing Q even in the "super-Q" limit, when the bandwidth of the tuned detection circuit is smaller than that of the signal to be detected. In the super-Q limit, the maximum obtainable SNR is thus limited by noise from the amplifiers in the system. This contrasts with typical NMR measurements where the ultimate SNR is limited by thermal noise from the detection circuit. Explicit expressions are derived and are compared to experiments performed using electronically simulated spin echo signals. (C) 1998 Academic Press. C1 Michigan Technol Univ, Dept Phys, Houghton, MI 49931 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Suits, BH (reprint author), USN, Res Lab, Div Chem, Washington, DC 20375 USA. NR 15 TC 14 Z9 14 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD MAY PY 1998 VL 132 IS 1 BP 54 EP 64 DI 10.1006/jmre.1998.1383 PG 11 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA ZR481 UT WOS:000073981300007 ER PT J AU Valent, PJ Young, D Sawyer, WB Wright, TD AF Valent, PJ Young, D Sawyer, WB Wright, TD TI Abyssal seafloor waste isolation: the concept SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE deep-sea environment; waste disposal; solid waste; risk assessment; concepts; Law of the Sea AB The Naval Research Laboratory (NRL), with industry and university participation, conducted an assessment of the concept of isolating certain wastes (i,e., sewage sludge, fly ash from municipal incinerators, and contaminated dredged material) on the oceans' abyssal seafloor. In this assessment the advantages, disadvantages, and economic and environmental viability of potential engineering methods for achieving abyssal waste isolation were identified and compared. This paper presents background to the Abyssal Plains Waste Isolation (APWI) Project, describes the characteristics of the waste streams and quantities potentially available for disposal via the abyssal isolation concept, summarizes regulations affecting use of the abyssal seafloor for disposal of wastes, and introduces the technical and scientific premises underlying implementation of the concept. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Valent, PJ (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. EM phil.valent@nrlssc.navy.mil NR 45 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD MAY PY 1998 VL 14 IS 3-4 BP 203 EP 210 DI 10.1016/S0924-7963(97)00027-4 PG 8 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA ZQ827 UT WOS:000073906900002 ER PT J AU Bowles, FA Vogt, PR Jung, WY AF Bowles, FA Vogt, PR Jung, WY TI Bathymetry (Part I), sedimentary regimes (Part II), and abyssal waste-disposal potential near the conterminous United States SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE abyssal plains; bathymetry; deep-sea environment; mass movements; waste disposal ID BANKS TURBIDITY-CURRENT; HUANGHE YELLOW-RIVER; NAVY SUBMARINE FAN; GRAND-BANKS; BRITISH-COLUMBIA; CALIFORNIA; DEPOSITION; ATLANTIC; FLOW; TRANSPORT AB Placing waste on the seafloor, with the intention that it remain in place and isolated from mankind, requires a knowledge of the environmental factors that may be applicable to a specific seafloor area. DBDB5 (Digital Bathymetric Database gridded at 5' latitude by 5' longitude cell dimension) is used here for regional assessments of seafloor depth, slope, and relief at five surrogate abyssal waste sites; two each in the western Atlantic and eastern Pacific, and one in the Gulf of Mexico. Only Pacific-1 exhibits a 'high' slope (2 degrees) by DBDB5 standards, whereas the remaining sites are located on almost level seafloor. Detailed examination of the sites using multibeam-based contour sheets show the area around Atlantic-1 to be a featureless plain. Atlantic-2 and both Pacific sites are surrounded by abyssal hill topography, with local slopes ranging from greater than 6 degrees at all sites to above 15 degrees at Pacific-2. Neither Pacific site features a seafloor as 'flat' as at Atlantic-1 or at the Gulf of Mexico site. Locating waste sites on sedimented slopes could have serious consequences due to catastrophic slope failure and downslope displacement of waste by mass sediment-transport processes. Neither slumping nor sliding are perceived as critical processes affecting the surrogate sites because of their locations on negligibly sloping seafloors. However, debris flows and turbidity currents are capable of transporting large volumes of sediment for long distances over low gradients and, in the case of turbidity currents, at great speed. Dispersal of loose waste material by these processes is virtually assured, but less likely if the waste is bagged. The turbidity current problem is alleviated (but not eliminated) by locating waste sites on distal portions of abyssal plains. Both Pacific sites are surrounded by abyssal hills and, in the case of Pacific-2, far beyond the reach of land-derived turbidity currents, Thin sediment cover and low rates of sedimentation have also resulted in highly stable slope (abyssal hill) deposits. Hence, the probability of locally derived, small-volume flows is low at these sites. Existing high sea levels have also resulted in a worldwide decrease in turbidity current activity relative to glacial times when sea levels were much lower. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Marine Geosci Div, Stennis Space Ctr, MS 39529 USA. USN, Res Lab, Marine Geosci Div, Washington, DC 20375 USA. RP Bowles, FA (reprint author), USN, Res Lab, Marine Geosci Div, Seafloor Sci, Stennis Space Ctr, MS 39529 USA. NR 75 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD MAY PY 1998 VL 14 IS 3-4 BP 211 EP 239 DI 10.1016/S0924-7963(97)00028-6 PG 29 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA ZQ827 UT WOS:000073906900003 ER PT J AU Fleischer, P Bowles, FA Richardson, MD AF Fleischer, P Bowles, FA Richardson, MD TI Identification of potential sites for deep-ocean waste isolation with a geographic site-selection model SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE waste disposal; site exploration; digital simulation; deep-sea environment; Gulf of Mexico; Northwest Atlantic; Northeast Pacific ID EASTERN EQUATORIAL PACIFIC; WESTERN NORTH-ATLANTIC; ORGANIC-CARBON; SEDIMENTS; DISTRIBUTIONS; PB-210 AB Identification of optimal sites for the isolation of waste on the abyssal seafloor was performed with two approaches: by the traditional method of map overlays of relevant attributes, and by a specially developed, automated Site-Selection Model (SSM). Five initial, Surrogate Sites, identified with the map-overlay approach, were then compared with the mon rigorously produced scores from the SSM. The SSM, a process for optimization of site locations, accepts subjective, expert-based judgments and transforms them into a quantitative, reproducible, and documented product. The SSM is adaptable to any siting scenario. Forty-one factors relevant to the isolation scenario, including 21 weightable factors having a total of 123 scorable categories, have been entered into the SSM. Factors are grouped under project definition, unique environments, anthropogenic, geologic, biologic, weather, oceanographic and distance criteria. The factor scores are linked to a georeferenced database array of all factors, corresponding to 1 degrees x 1 degrees latitude-longitude squares. The SSM includes a total of 2241 one-degree squares within 1000 n.m. of the U.S. coasts, including the western North Atlantic, the Gulf of Mexico, and the eastern North Pacific. Under a carefully weighted and scored scenario of isolation, the most favorable sites identified with the SSM are on the Hatteras and Nares Abyssal Plains in the Atlantic. High-scoring sites are also located in the Pacific abyssal hills province between the Murray and Molokai Fracture Zones. Acceptable 1 degrees squares in the Gulf of Mexico are few and of lower quality, with the optimum location on the northern Sigsbee Abyssal Plain. Two of the five Surrogate Site locations, on the Hatteras and Sigsbee Abyssal Plains, correspond to the best SSM sites in each ocean area. Two Pacific and a second Atlantic Surrogate Site are located in low-scoring regions or excluded by the SSM. Site-selection results from the SSM, although robust, are an initial attempt to quantify the site-selection process. The SSM database exposes a significant lack of high-quality information for many areally mappable attributes on the abyssal seafloor, particularly bottom-current speed and measures of biologic productivity and flux. Terminologies and classifications of some measures, such as sediment types, suffer from parochialism and vary by ocean. Considerable research is needed even for a broad understanding of the environmental measures required to make sound societal decisions about use of the abyssal seafloor for disposal or other purposes. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Seafloor Sci Div, Stennis Space Ctr, MS 39529 USA. RP Fleischer, P (reprint author), USN, Res Lab, Seafloor Sci Div, Stennis Space Ctr, MS 39529 USA. EM pete.fleischer@nrlssc.navy.mil NR 75 TC 6 Z9 6 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD MAY PY 1998 VL 14 IS 3-4 BP 241 EP 271 DI 10.1016/S0924-7963(97)00029-8 PG 31 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA ZQ827 UT WOS:000073906900004 ER PT J AU Valent, PJ Palowitch, AW Young, DK AF Valent, PJ Palowitch, AW Young, DK TI Engineering concepts for the placement of wastes on the abyssal seafloor SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE deep-sea environment; waste disposal; solid waste; risk assessment; techniques; reliability; abyssal plains AB The Naval Research Laboratory (NRL), with industry and academic participation, has completed a study of the concept of isolating industrial wastes (i.e., sewage sludge, fly ash from municipal incinerators, and dredged material) on the abyssal seafloor. This paper presents results of the technical and economic assessment of this waste management concept. The results of the environmental impacts portion of the study are presented in a companion paper. The technical assessment began with identification of 128 patents addressing waste disposal in the ocean. From these 128 patents, five methods for transporting wastes through the water column and emplacing wastes within an easily monitored area on the abyssal seafloor were synthesized for technical assessment. In one method waste is lowered to the seafloor in a bucket of 190 m(3). In a second method waste is pumped down to the seafloor in pipes, 1.37 m in diameter and 6100 m in length. In a third method waste is free-fallen from the ocean surface in 380-m(3) geosynthetic fabric containers (GFCs), Tn the fourth and fifth methods, waste is carried to near the seafloor in GFCs transported in (a) a 20,000 metric ton displacement (loaded), unpowered, unmanned submersible glider, or (b) a 2085 metric ton displacement (loaded) disk-shaped transporter traversing to and from the seafloor much like an untethered elevator. In the last two methods the transporter releases the GFCs to free-fall the last few hundred meters to the seafloor. Two reliability analyses, a Fault Tree Analysis (FTA), and a Failure Modes, Effects, and Criticality Analysis (FMECA), showed that the free-fall GFC method posed the least overall relative risk, provided that fabric container and transporter designs eliminate the potential for tearing of the containers on release from the surface transporter. Of the five methods, the three GFC methods were shown to offer cost-effective waste management options when compared with present-day waste management techniques in higher-priced areas, such as the New York-New Jersey area. In conclusion, the abyssal seafloor waste isolation concept is technically feasible and cost-effective for many waste sources. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Valent, PJ (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 14 TC 4 Z9 4 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD MAY PY 1998 VL 14 IS 3-4 BP 273 EP 288 DI 10.1016/S0924-7963(97)00030-4 PG 16 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA ZQ827 UT WOS:000073906900005 ER PT J AU Gallacher, PC Hogan, PJ AF Gallacher, PC Hogan, PJ TI Hydrodynamical dispersion of dredged materials sequestered on the abyssal seafloor SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE deep-sea environment; isolation; Northwest Atlantic; numerical models; ocean circulation; radioactive tracers ID LIMITED-AREA MODEL; NORTH-ATLANTIC; GULF-STREAM; BOUNDARY CURRENT; RECIRCULATION; CIRCULATION; SYSTEM AB This paper addresses the potential dispersion by hydrodynamical processes of dredged material disposed on the abyssal seafloor off the east coast of the United States. The importance of the large-scale mean currents and of the eddy kinetic energy of the large-scale flow are discussed both for the selection of potential isolation sites and for determining the potential dispersion pattern from selected sites. These processes play a particularly significant role in the Atlantic off the east coast of the United States. There the potential isolation sites are close to a highly energetic region of the abyssal circulation, the North Atlantic Deep Western Boundary Current. The Naval Research Laboratory Layered Ocean Model was used to simulate large-scale ocean circulation in the North Atlantic Subtropical Gyre. Numerical experiments were conducted using monthly climatological forcing. High horizontal resolution, 1/16 degrees, was required to achieve a realistic level of kinetic energy in the deep ocean and a realistic deep mean flow. The prognostic variables came to statistical equilibrium after 50 years of simulation. Then the mean currents and eddy kinetic energy were calculated based on 4 years of simulated data. The patterns and magnitudes of the currents and kinetic energy from the simulation agreed with the observations. The simulated pathways of the Deep Western Boundary Current including bifurcations and reconnections conformed to current concepts of its circulation. The recirculation gyres under the Gulf Stream were simulated, as were the eddies, meanders and high levels of eddy kinetic energy northeast of the New England Seamount chain. The decrease in eddy kinetic energy to the south over the Hatteras Abyssal Plain and the weak currents in the region of 25 degrees N to 30 degrees N along 70 degrees W were also in agreement with observations and verified the results of the site selection model. Tracers were released into the 1 degrees squares that were chosen by the NRL site selection model as the best candidates for isolation of dodged material. Modest quantities of the tracers were dispersed beyond the initial release areas and only trace amounts were mixed out of the bottom layer of the model. The results of this study indicate that if contaminated material was released into the water column from isolation sites in the region chosen by the site selection model it would probably be dispersed over a limited area. However, the dispersion of the tracers was anisotropic and varied spatially among the sites. This underscores the need to conduct both boundary layer-scale and gyre-scale numerical simulations and careful measurement programs at the sites chosen for initial evaluation of deep-ocean isolation of dredged material. The next step is to run mesoscale models that use the results from this study as boundary conditions and the results from plume models of contaminant release to determine the amount of contaminated material that might leak out of the boundary layer into the deep-ocean circulation system. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Coupled Dynam Proc Sect, Ocean Sci Branch, Stennis Space Ctr, MS 39529 USA. USN, Res Lab, Ocean Monitoring & Predict Syst Sect, Ocean Dynam & Predict Branch, Stennis Space Ctr, MS 39529 USA. RP Gallacher, PC (reprint author), USN, Res Lab, Coupled Dynam Proc Sect, Ocean Sci Branch, Stennis Space Ctr, MS 39529 USA. NR 25 TC 6 Z9 6 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD MAY PY 1998 VL 14 IS 3-4 BP 305 EP 318 DI 10.1016/S0924-7963(97)00032-8 PG 14 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA ZQ827 UT WOS:000073906900007 ER PT J AU Young, DK Richardson, MD AF Young, DK Richardson, MD TI Effects of waste disposal on benthic faunal succession on the abyssal seafloor SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE deep sea environment; waste disposal; ecology; turbidity currents; bioturbation ID SEA HYDROTHERMAL VENT; PUERTO-RICO TRENCH; DEEP-SEA; VENEZUELA BASIN; CARIBBEAN SEA; GALAPAGOS RIFT; BIOLOGICAL COMMUNITIES; PELAGIC SEDIMENTS; BOTTOM CURRENTS; NORTH-ATLANTIC AB Strategies to predict, and thus limit, potentially detrimental environmental impacts of abyssal disposal of wastes are severely limited by our lack of knowledge of deep-sea processes and lack of opportunity to directly study waste disposal in abyssal environments. Probable successional sequences following burial of benthic faunas by sewage sludge and dredged material on the abyssal seafloor are drawn by analogy with well-known processes in shallow-marine water. Scales of change and recovery of abyssal benthic faunas from episodic deposition of waste material are examined by extrapolation from what is currently known about turbidite sedimentary provinces, in particular, the Venezuela Abyssal Plain and the Great Meteor East area of the Madeira Abyssal Plain. Results suggest that initial benthic faunal recolonization would take place within years following episodic depositions of waste on the abyssal seafloor. Anoxic conditions or chemical inhibitory effects may delay initial benthic recolonization for hundreds of years. Establishment of equilibrium benthic faunal assemblages probably takes hundreds to potentially thousands of years. Potentially detrimental effects dictate that the surface areas of individual waste deposits should be minimized and the deposits should be isolated by capping with nontoxic materials or chemical barriers. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Marine Geosci Div, Stennis Space Ctr, MS 39529 USA. USN, Res Lab, Div Oceanog, Stennis Space Ctr, MS 39529 USA. RP Richardson, MD (reprint author), USN, Res Lab, Marine Geosci Div, Stennis Space Ctr, MS 39529 USA. NR 100 TC 14 Z9 14 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD MAY PY 1998 VL 14 IS 3-4 BP 319 EP 336 DI 10.1016/S0924-7963(97)00033-X PG 18 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA ZQ827 UT WOS:000073906900008 ER PT J AU Fryauff, DJ Shoukry, MA Wassef, HY Gray, G Schreck, CE AF Fryauff, DJ Shoukry, MA Wassef, HY Gray, G Schreck, CE TI Contact toxicity of permethrin-impregnated fabric to Hyalomma anatolicum excavatum (Acari : Ixodidae): Effects of laundering and exposure and recovery times SO JOURNAL OF MEDICAL ENTOMOLOGY LA English DT Article DE Hyalomma anatolicum excavatum; permethrin; contact toxicity ID PERSONAL PROTECTION; CLOTHING TREATMENT; TICK ACARI; STIMULATION; ARGASIDAE AB A previous study that documented enhanced host attachment by the camel ticks Hyalomma dromedarii Koch after permethrin exposure prompted a similar investigation of permethrin effects in H. anatolicum excavatum Koch, an Old World hardbacked tick suspected of vectoring human pathogens. Contact toxicity tests were conducted with laboratory-colonized male and female H. a. excavatum of the same age exposed for periods of 5, 10, 30, and GO min to each of 5 fabric treatments: unwashed/untreated; unwashed and treated; and treated fabric given 1, 2, or 3 laundry cycles of warm-water detergent machine washing, followed by hot-air drying. Fabric was tropical weight 100% cotton military uniform. Treated fabric was impregnated with permethrin at 0.125 mg (Al)/cm(2). Contact toxicity was measured immediately after and 24 h after fabric contact as proportion of ticks that attached mouthparts to the skin of a host (rabbit) within a 60-min quest period and time lapse (minutes) between contact with the host and attachment. Attachment response immediately after. permethrin contact was exposure time-and wash-dependent in both sexes. Proportion of attaching ticks and times to attachment were comparable in controls and in groups exposed to all permethrin-treated fabrics for 5 or 10 min. Contact periods of 30 and GO min with 0-wash/treated or 1-wash and treated fabric significantly reduced the frequency of attachment and significantly prolonged mean times to attachment. Compared with low levels of attachment response observed immediately after fabric contact, recovery of attachment response was observed 24 h after exposure in these wash/treatment groups, but inhibition was still evident. Permethrin-induced intoxication was more pronounced in males than females. Mortality 24 h after exposure was only significant among females exposed to 0-wash/treated fabric for 60 min. There was no evidence of permethrin-mediated stimulation of the attachment response in H. a. excavatum. C1 USN, Res Publicat Branch, Res Unit 3, Res Sci Dept, FPO, AE 09835 USA. RP Fryauff, DJ (reprint author), USN, Res Publicat Branch, Res Unit 3, Res Sci Dept, Code 101F,PSC 452,Box 5000, FPO, AE 09835 USA. NR 14 TC 3 Z9 4 U1 0 U2 2 PU ENTOMOL SOC AMER PI LANHAM PA 9301 ANNAPOLIS RD, LANHAM, MD 20706 USA SN 0022-2585 J9 J MED ENTOMOL JI J. Med. Entomol. PD MAY PY 1998 VL 35 IS 3 BP 335 EP 339 PG 5 WC Entomology; Veterinary Sciences SC Entomology; Veterinary Sciences GA ZP647 UT WOS:000073774400024 PM 9615556 ER PT J AU Mathews, WB Kinter, CM Palma, J Daniels, RV Ravert, HT Scheffel, U McCallister, SL Chapman, SA Finley, PA Dannals, RF Lever, JR AF Mathews, WB Kinter, CM Palma, J Daniels, RV Ravert, HT Scheffel, U McCallister, SL Chapman, SA Finley, PA Dannals, RF Lever, JR TI N1 '-([F-18] fluorethyl)naltrindole ([F-18]FetNTI): A radioligand for positron emission tomographic studies of delta opioid receptors. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Johns Hopkins Univ, Baltimore, MD USA. USN Acad, Annapolis, MD 21402 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1998 VL 39 IS 5 SU S MA 73 BP 21P EP 21P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA ZM639 UT WOS:000073560300074 ER PT J AU Denison, GL Jones, SB Maher, JM Cole, RL Gorman, JD Puckett, MP Goff, WB Kipper, MS AF Denison, GL Jones, SB Maher, JM Cole, RL Gorman, JD Puckett, MP Goff, WB Kipper, MS TI Femoral neck stress fractures in endurance athletes: Increased detection with SPECT. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Naval Hosp, Okinawa, Japan. USN, Ctr Med, San Diego, CA USA. Univ Calif San Diego, San Diego, CA 92103 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1998 VL 39 IS 5 SU S MA 505 BP 128P EP 129P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA ZM639 UT WOS:000073560300504 ER PT J AU Soyer, AD Nowotarski, PJ Kelso, TB Mighell, MA AF Soyer, AD Nowotarski, PJ Kelso, TB Mighell, MA TI Optimal position for plate fixation of complex fractures of the proximal radius: A cadaver study SO JOURNAL OF ORTHOPAEDIC TRAUMA LA English DT Article DE radius; fractures; plate; fixation; cadaver ID INTERNAL-FIXATION; HEAD AB Objective: To determine the optimal postion for plate fixation in complex fractures of the proximal radius in which head and neck dissociation occurs. Design: Technical study. Setting: Tertiary referral center, teaching hospital, U.S. military. Subjects: Five preserved cadavers. Main Outcome Measure: Radioulnar impingement and proximity to neurovascular structures were directly measured in elbows plated in each of three positions: neutral, full pronation, and full supination. Results: Application of the 2.0-millimeter T-plate to the lateral aspect of the radial head and neck with the forearm in neutral position had no impingement, whereas application in full pronation resulted in loss of the last 30 degrees of supination. Plate application in full supination resulted in the loss of the last 10 degrees of pronation. In addition, there was no impingement when the 2.7-millimeter plate was applied similarily in the neutral position. None of these positions resulted in increased risk to neurovascular structures. Conclusions: The optimal position for plate fixation of complex proximal radius fractures is with the forearm in neutral position, with the plate applied directly lateral. A larger implant, 2.7 millimeters, may be used if this technique is followed without further risk of impingement and loss of motion. C1 Hudson Valley Orthopaed Ctr, Kingston, NY 12401 USA. R Adams Cowley Shock Trauma Ctr, Baltimore, MD USA. USN, Med Ctr, Dept Orthopaed, Portsmouth, VA USA. RP Kelso, TB (reprint author), Hudson Valley Orthopaed Ctr, Broadway Med Pavil,367 Broadway, Kingston, NY 12401 USA. NR 13 TC 16 Z9 16 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0890-5339 J9 J ORTHOP TRAUMA JI J. Orthop. Trauma PD MAY PY 1998 VL 12 IS 4 BP 291 EP 293 DI 10.1097/00005131-199805000-00013 PG 3 WC Orthopedics; Sport Sciences SC Orthopedics; Sport Sciences GA ZM882 UT WOS:000073585800013 PM 9619466 ER PT J AU Hilfiker, ML Hart, M Holmes, R Cooper, M Kriett, J Collins, D Allshouse, M AF Hilfiker, ML Hart, M Holmes, R Cooper, M Kriett, J Collins, D Allshouse, M TI Expansion and division of conjoined twins SO JOURNAL OF PEDIATRIC SURGERY LA English DT Article DE conjoined twins; tissue expanders; liver AB Omphalopagus conjoined twins were born by cesarean section after their 24-year-old gravida 2, para 1 mother went into labor at 35 weeks' gestation. Initial studies included roentenograms, an upper gastrointestinal study, small bowel follow-through, and computerized tomography with intravenous contrast from neck through pelvis. Results of these studies showed that the twins had very little shared vasculature, but did share a pericardium and liver parenchyma. The infants were allowed to gain weight and grow. After 3 weeks, tissue expanders were placed subcutaneously and were rapidly expanded in 2 weeks. The infants were then separated. An Argon Beam Coagulator was used to aid the separation of the liver. The abdominal fascia was closed primarily on each infant, and the skin easily closed without tension. During the first 36 hours of the postoperative course, both infants required significant ventilatory support including inhaled nitric oxide. After this period, the ventilatory support decreased dramatically and rapidly. The infants were discharged 9 days after their surgical separation. Conjoined omphalopagus twins, the use of tissue expanders and the Argon Beam Coagulator, and the postoperative course are discussed. Copyright (C) 1998 by W.B. Saunders Company. C1 Univ Calif San Diego, Med Ctr, Childrens Hosp & Hlth Ctr, Dept Surg, San Diego, CA 92103 USA. USN, Med Ctr, San Diego, CA 92152 USA. RP Hilfiker, ML (reprint author), Univ Calif San Diego, Med Ctr, Dept Pediat Surg, 200 W Arbor Dr,8404, San Diego, CA 92103 USA. NR 5 TC 7 Z9 14 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 0022-3468 J9 J PEDIATR SURG JI J. Pediatr. Surg. PD MAY PY 1998 VL 33 IS 5 BP 768 EP 770 DI 10.1016/S0022-3468(98)90215-9 PG 3 WC Pediatrics; Surgery SC Pediatrics; Surgery GA ZM669 UT WOS:000073564000031 PM 9607496 ER PT J AU White, C AF White, C TI Repair of a root resorption lesion. A case report SO JOURNAL OF PERIODONTOLOGY LA English DT Article DE biocompatible materials; surgical flaps; tooth root; glass, ionomer cements ID GLASS-IONOMER CEMENTS AB AN EXTENSIVE ROOT SURFACE LESION that presented both supra-and subgingival components was successfully treated with the use of glass ionomer cement to restore the lesion, and facilitate subsequent endodontic therapy and restoration. A coronally-positioned flap covered the repaired/restored lesion, approximately 6 mm x 10 mm in dimension. At 6 months following placement of the restoration, all but 1 mm of the restoration appeared covered, with probing depths <3 mm and no clinical signs of inflammation. Glass ionomer cement appears to be a viable, biocompatible material to restore subgingival root surface lesions. C1 USN, Dent Ctr, Dept Periodont, Newport, RI USA. RP White, C (reprint author), Branch Dent Clin Newport, 1173 Whipple St, Newport, RI 02840 USA. NR 16 TC 11 Z9 11 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 MAY PY 1998 VL 69 IS 5 BP 596 EP 600 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA ZQ378 UT WOS:000073855200012 PM 9623904 ER PT J AU Chu, PC Chen, YC Lu, SH AF Chu, PC Chen, YC Lu, SH TI On Haney-type surface thermal boundary conditions for ocean circulation models SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID THERMOHALINE CIRCULATION; HEAT; FLUX; TEMPERATURE; VARIABILITY AB Haney-type surface thermal boundary conditions linearly connect net downward surface heat flux Q to air-sea temperature difference (gradient-type condition) Delta T-1 or to climate/synoptic sea temperature difference (restoring-type condition) Delta T-2 by a coupling coefficient kappa. In this study, the authors used the global reanalyzed data (6-h resolution) of Q, surface air temperature T-A, and sea surface temperature T-o from the National Centers for Environmental Prediction during 1 October 1994-31 December 1995 to verify the validity of Haney-type surface thermal boundary conditions. First, daily means of these variables were computed to get rid of diurnal variation. Second, the cross-correlation coefficients (CCC) between Q and (Delta T-1, Delta T-2) were calculated. The ensemble mean CCC fields show (i) no correlation between Q and Delta T-2 anywhere in the world oceans, (ii) no correlation between Q and Delta T-1 in the equatorial regions, and (c) evident correlation (CCC greater than or equal to 0.7) between Q and Delta T-1 in the middle and high latitudes. Third. the variance analysis was conducted and a value of 70 W m(-2) K-1 (65 W m(-2) K-1) was suggested for the coupling coefficient kappa in the northern (southern) middle and high latitude zone. Thus, the authors find that the restoring-type surface thermal conditions by no means represent the net air-ocean heat flux anywhere in the world oceans. However, the gradient type surface thermal condition represents the net hear flux quite well for the middle and high latitudes. in addition, it is also found that, if the solar shortwave component is treated separately, the gradient-type condition will have more fidelity for the middle and high latitudes. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. EM chu@nps.navy.mil NR 18 TC 13 Z9 15 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 EI 1520-0485 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD MAY PY 1998 VL 28 IS 5 BP 890 EP 901 DI 10.1175/1520-0485(1998)028<0890:OHTSTB>2.0.CO;2 PG 12 WC Oceanography SC Oceanography GA ZP532 UT WOS:000073762900009 ER PT J AU Araujo, EB De Paiva, JAC Freitas, JA Sombra, ASB AF Araujo, EB De Paiva, JAC Freitas, JA Sombra, ASB TI Raman and infrared spectroscopy studies of LiNbO3 in niobate glass-ceramics SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article DE glass; ceramics; ferroelectricity ID OPTICAL-PROPERTIES; PHOSPHATE GLASSES; SILICATE-GLASSES; GALLATE GLASSES AB Optical and structural properties of lithium niobophosphate glasses, with composition [xNb(2)O(5) .(50-x)P2O5 . 5OLi(2)O]:yFe(2)O(3), were studied by X-ray powder diffraction, infrared and Raman spectroscopies. Precipitation of ferroelectric LiNbO3 crystals was confirmed by X-ray powder diffraction in the sample 10Nb(2)O(5)-40P(2)O(5)-50Li(2)O:2Fe(2)O(3), under heat treatment. The crystallization processes of phosphorus-oxygen groups of different degrees of complexity, such as LiPO3, LiP2O7 and Li3PO4, were observed. The infrared and Raman spectroscopy results suggest that the increase of the ratio Nb2O5/P2O5 leads the niobium to sites of octahedral symmetry and consequently to the formation of ferroelectric LiNbO3, as observed by X-ray diffraction analysis. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Fed Ceara, Dept Fis, LONLCM, BR-60451970 Fortaleza, Ceara, Brazil. USN, Res Lab, Washington, DC 20375 USA. RP Sombra, ASB (reprint author), Univ Fed Ceara, Dept Fis, LONLCM, Caixa Postal 6030, BR-60451970 Fortaleza, Ceara, Brazil. RI Araujo, E/A-7104-2013; Sombra, Antonio /B-2963-2013; UFC, DF/E-1564-2017; Universidade Federal do Ceara, Physics Department/J-4630-2016 OI Universidade Federal do Ceara, Physics Department/0000-0002-9247-6780 NR 22 TC 22 Z9 22 U1 0 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 EI 1879-2553 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAY PY 1998 VL 59 IS 5 BP 689 EP 694 DI 10.1016/S0022-3697(97)00228-X PG 6 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA ZN385 UT WOS:000073640600015 ER PT J AU Tuncer, IH Platzer, MF AF Tuncer, IH Platzer, MF TI Potential flow solutions with wakes over an ogive cylinder SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB An incompressible panel code is employed to compute the flow over an ogive cylinder body with an overall length of 7.5 diameter. Flow separation is modeled by vortex wakes attached to the base region and the leeward sides of the cylinder body. The computed surface pressures and integrated normal force and pitching-moment coefficients are found to be in good agreement with the experimental data up to 20-deg incidence. This favorable agreement suggests that the panel codes may be a computationally efficient tool in the aerodynamic missile design process at low incidences. 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 17 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 MAY-JUN PY 1998 VL 35 IS 3 BP 273 EP 277 DI 10.2514/2.3351 PG 5 WC Engineering, Aerospace SC Engineering GA ZT729 UT WOS:000074119200005 ER PT J AU Ross, IM Nicholson, JC AF Ross, IM Nicholson, JC TI Optimality of the heating-rate-constrained aerocruise maneuver SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID AEROASSISTED ORBITAL TRANSFER; PLANE CHANGE AB A synergetic maneuver can accomplish orbital plane changes with less fuel than an exoatmospheric maneuver. During the atmospheric pass, the spacecraft is subjected to very high heating rates, and any extra thermal protection required may offset the fuel savings. A heating-rate-constrained synergetic maneuver called aerocruise has been widely studied as a means for lowering the weight of the thermal protection system. We question the optimality of the aerocruise maneuver by considering the necessary and sufficient condition for a trajectory to remain on the heating-rate boundary. By replacing the aerocruise-powered turn by a maximum thrust maneuver that we call aerobang, a perturbed synergetic maneuver is obtained. This maneuver is compared against the numerically optimized aerocruise maneuver for the entry research vehicle. The results demonstrate that the aerobang maneuver consistently yields improved performance, i.e., inclination change per fuel mass, over the aerocruise maneuver by as much as 14%. This result indicates that the optimal synergetic maneuver is yet to be determined and could very well be more complicated than a simple aerocruise turn. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Ross, IM (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Mail Code AA-Ro, Monterey, CA 93943 USA. NR 17 TC 3 Z9 4 U1 1 U2 2 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 MAY-JUN PY 1998 VL 35 IS 3 BP 361 EP 364 DI 10.2514/2.3335 PG 4 WC Engineering, Aerospace SC Engineering GA ZT729 UT WOS:000074119200017 ER PT J AU Trent, LK AF Trent, LK TI Evaluation of a four- versus six-week length of stay in the Navy's alcohol treatment program SO JOURNAL OF STUDIES ON ALCOHOL LA English DT Article ID PATIENT TREATMENT; HEALTH-CARE; SEVERITY; READMISSION; AFTERCARE AB Objective: Attempts to balance escalating health care costs with resource downsizing have prompted alcohol treatment directors in the U.S. Navy to consider reducing the standard length of stay in treatment. The objectives of this study were to (1) determine whether a 4-week inpatient treatment program is as effective as a 6-week; program, and (2) explore the potential for matching patients to a 4- or 6-week program according to the severity of their condition at intake. Method: A total of 2.823 active-duty alcohol-dependent inpatients (2,685 men, 138 women) at 12 Navy treatment facilities participated in the evaluation. All facilities conducted a 6-week program until data had been collected for 1,380 participants; they then switched to a ii-week program (n = 1,443). Background information and clinical profile were obtained when patients entered treatment; 1-year outcome data (e.g., alcohol use, behavior problems, job performance, quality of life) were obtained from participants, work supervisors and aftercare advisors. Hierarchical multiple regression analysts were used to assess the effect of length of stay on outcome and to examine patient-program interactions. Results: The single best predictor of success at 1 year was months of aftercare attendance. Program membership failed to explain any of the observed differences in the criterion measures, once the effects of other predictors had been taken into account. Severity of condition and patient-program interactions were likewise nonsignificant. Conclusions: It was concluded that a reduction in length of stay from 6 weeks to 4 weeks in the Navy's inpatient alcohol treatment program would not have an adverse effect on outcome. C1 USN, Hlth Res Ctr, Hlth Sci & Epidemiol Dept, San Diego, CA 92186 USA. RP Trent, LK (reprint author), USN, Hlth Res Ctr, Hlth Sci & Epidemiol Dept, POB 85122, San Diego, CA 92186 USA. NR 41 TC 11 Z9 11 U1 0 U2 2 PU ALCOHOL RES DOCUMENTATION INC CENT ALCOHOL STUD RUTGERS UNIV PI PISCATAWAY PA C/O DEIRDRE ENGLISH, 607 ALLISON RD, PISCATAWAY, NJ 08854-8001 USA SN 0096-882X J9 J STUD ALCOHOL JI J. Stud. Alcohol PD MAY PY 1998 VL 59 IS 3 BP 270 EP 279 PG 10 WC Substance Abuse; Psychology SC Substance Abuse; Psychology GA ZJ748 UT WOS:000073249000004 PM 9598707 ER PT J AU Lodha, GS Yamashita, K Haga, K Kunieda, H Nakajo, N Nakamura, N Tamura, K Tawara, Y Bennett, JM AF Lodha, GS Yamashita, K Haga, K Kunieda, H Nakajo, N Nakamura, N Tamura, K Tawara, Y Bennett, JM TI Characterization of substrates for use in X-ray multilayer optics SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 6th International Conference on Synchrotron Radiation Instrumentation (SRI'97) CY AUG 04-08, 1997 CL HIMEJI, JAPAN SP Japan Atom Energy Res Inst (JAERI), Inst Phys & Chem Res (RIKEN) DE X-ray multilayers; X-ray reflectivity; diffuse scattering; scanning probe microscopes; surface roughness ID INTERFACIAL ROUGHNESS; SCATTERING; SOFT AB The optical performance of platinum-carbon multilayers deposited onto different substrates has been examined. Specular reflectivity and non-specular diffuse scattering were measured to study the replication of substrate roughness into the multilayer structure. Surface topography was measured before and after deposition using a scanning probe microscope and a mechanical profiler. C1 Nagoya Univ, Dept Phys, Chikusa Ku, Nagoya, Aichi 4648602, Japan. USN, Air Warfare Ctr, China Lake, CA 93555 USA. Chubu Univ, Dept Engn Mech, Kasugai, Aichi 487, Japan. RP Lodha, GS (reprint author), Nagoya Univ, Dept Phys, Chikusa Ku, Furo Cho, Nagoya, Aichi 4648602, Japan. NR 10 TC 1 Z9 1 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1998 VL 5 BP 693 EP 695 DI 10.1107/S0909049598000958 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 103UA UT WOS:000074975200158 PM 15263622 ER PT J AU Cross, JO Elam, WT Harris, VG Kirkland, JP Bouldin, CE Sorensen, LB AF Cross, JO Elam, WT Harris, VG Kirkland, JP Bouldin, CE Sorensen, LB TI Sample-angle feedback for diffraction anomalous fine-structure spectroscopy SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 6th International Conference on Synchrotron Radiation Instrumentation (SRI'97) CY AUG 04-08, 1997 CL HIMEJI, JAPAN SP Japan Atom Energy Res Inst (JAERI), Inst Phys & Chem Res (RIKEN) DE diffraction anomalous fine structure; XAFS; anomalous scattering; sample-angle feedback ID MONOCHROMATOR AB Diffraction anomalous fine-structure (DAFS) experiments measure Bragg peak intensities as continuous functions of photon energy near a core-level excitation. Measuring the integrated intensity at each energy makes the experiments prohibitively slow; however, in many cases DAFS can be collected quickly by measuring only the peak intensity at the center of the rocking curve. A piezoelectric-actuator-driven stage has been designed and tested as part of a sample-angle feedback circuit for locking onto the maximum of the rocking curve while the energy is scanned. Although software peak-tracking requires only a simple calculation of diffractometer angles, it is found that the additional hardware feedback dramatically improves the reproducibility of the data. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Landover, MD 20785 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Washington, Seattle, WA 98195 USA. RP Cross, JO (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Harris, Vincent/A-8337-2009 NR 7 TC 3 Z9 3 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1998 VL 5 BP 911 EP 913 DI 10.1107/S0909049597014313 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 103UA UT WOS:000074975200230 PM 15263694 ER PT J AU Larraza, A Holmes, CD Susbilla, RT Denardo, B AF Larraza, A Holmes, CD Susbilla, RT Denardo, B TI The force between two parallel rigid plates due to the radiation pressure of broadband noise: An acoustic Casimir effect SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB Theoretical and experimental results are presented for the force law between two rigid, parallel plates due to the radiation pressure of broadband acoustic noise. The noise is in the band of 5-15 kHz and has an intensity of 133 dB (re: 10(-12) W/m(2)). Excellent quantitative agreement is shown between theory and experiment. These results constitute an acoustic analog for the Casimir effect, which is the force experienced by two closely spaced uncharged conducting plates due to the quantum electromagnetic zero-point field. In contrast to this case, however, band-limited noise can cause the force to be attractive or repulsive as a function of separation between the plates. (C) 1998 Acoustical Society of America. C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. Univ Mississippi, Dept Phys & Astron, University, MS 38677 USA. Univ Mississippi, Natl Ctr Phys Acoust, University, MS 38677 USA. RP Larraza, A (reprint author), USN, Postgrad Sch, Dept Phys, Code PH LA, Monterey, CA 93943 USA. NR 13 TC 16 Z9 16 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 MAY PY 1998 VL 103 IS 5 BP 2267 EP 2272 DI 10.1121/1.422744 PN 1 PG 6 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZM942 UT WOS:000073591800002 ER PT J AU Pflug, LA Ioup, GE Ioup, JW AF Pflug, LA Ioup, GE Ioup, JW TI Known source detection predictions for higher order correlators SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID NON-GAUSSIAN SIGNALS; TRANSIENT SIGNALS; SPECTRA AB The problem addressed in this paper is whether higher order correlation detectors can perform better in white noise than the cross correlation detector for the detection of a known transient source signal, if additional receiver information is included in the higher order correlations. While the cross correlation is the optimal linear detector for white noise, additional receiver information in the higher order correlations makes them nonlinear. In this paper, formulas that predict the performance of higher order correlation detectors of energy signals are derived for a known source signal. Given the first through fourth order signal moments and the noise variance, the formulas predict the SNR for which the detectors achieve a probability of detection of 0.5 for any level of false alarm, when noise at each receiver is independent and identically distributed. Results show that the performance of the cross correlation, bicorrelation, and tricorrelation detectors are proportional to the second, fourth, and sixth roots of the sampling interval, respectively, but do not depend on the observation time. Also, the SNR gains of the higher order correlation detectors relative to the cross correlation detector improve with decreasing probability of false alarm. The source signal may be repeated in higher order correlations, and gain formulas are derived for these cases as well. Computer simulations with several test signals are compared to the performance predictions of the formulas. The breakdown of the assumptions for signals with too few sample points is discussed, as are limitations on the design of signals for improved higher order gain. Results indicate that in white noise it is difficult for the higher order correlation detectors in a straightforward application to achieve better performance than the cross correlation. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Univ New Orleans, Dept Phys, New Orleans, LA 70148 USA. RP Pflug, LA (reprint author), USN, Res Lab, Code 7173, Stennis Space Ctr, MS 39529 USA. NR 23 TC 3 Z9 3 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 MAY PY 1998 VL 103 IS 5 BP 2469 EP 2477 DI 10.1121/1.422767 PN 1 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZM942 UT WOS:000073591800025 ER PT J AU Turk, J Marzano, FS Mugnai, A AF Turk, J Marzano, FS Mugnai, A TI Effects of degraded sensor resolution upon passive microwave precipitation retrievals of tropical rainfall SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID CONVECTIVE-SYSTEMS; RADAR MEASUREMENTS; PROFILE RETRIEVAL; CLOUD MODEL; RADIOMETER; ALGORITHM; STORMS; CAPE AB Based on the fundamental relationship involving the interaction of microwave radiation with precipitation, microwave-based satellite precipitation estimates hold the most promise for quantitative rain estimation from space. At present, the low-resolution channels onboard the DMSP Special Sensor Microwave Imager (SSM/I) are sampled with a spatial resolution several times larger than the scale at which rainfall is generated in typical convective rainbands. Aircraft-based instruments can provide views of the detailed microwave radiometric characteristics of precipitating clouds. In this manuscript, the authors present coincident finescale (1-3 km resolution) collocated aircraft radiometric and aircraft precipitation radar measurements collected during the 1993 Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment in the western Pacific Ocean. By intentionally degrading the resolution of the aircraft datasets from their native resolution to that of current and future spaceborne sensors, the impact of sensor resolution upon a combined radiometer-radar vertical profiling rain-retrieval algorithm (developed and utilized for the Precipitation Intercomparison Program 2) was examined. Retrieved values of the columnar graupel content were more influenced by the addition of the radar profile than was the columnar rain content. The retrieved values of columnar graupel were also significantly smaller than previously published results for land-based rainfall. The results show that the general trend of the rain structure is maintained but finescale details are lost once the observations are reduced to resolutions of 15 km. C1 USN, Res Lab, Marine Meteorol Div, Monterey, CA 93943 USA. Univ Roma La Sapienza, Dipartimento Ingn Elettron, Rome, Italy. CNR, Ist Fis Atmosfera, I-00044 Frascati, Italy. RP Turk, J (reprint author), USN, Res Lab, Marine Meteorol Div, 7 Grace Hopper Ave, Monterey, CA 93943 USA. EM turk@nrlmry.navy.mil NR 35 TC 12 Z9 12 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD MAY 1 PY 1998 VL 55 IS 9 BP 1689 EP 1705 DI 10.1175/1520-0469(1998)055<1689:EODSRU>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZM952 UT WOS:000073592900012 ER PT J AU Carlin, RT De Long, HC Fuller, J Trulove, PC AF Carlin, RT De Long, HC Fuller, J Trulove, PC TI Microelectrode evaluation of transition metal-aluminum alloy electrodepositions in chloroaluminate ionic liquids SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID TEMPERATURE MOLTEN-SALTS; ELECTRON-TRANSFER KINETICS; LITHIUM; GLASS; VOLTAMMETRY; COBALT AB Chronoamperometric data collected at a 250 mu m tungsten microelectrode were analyzed under near-steady-state conditions to determine the composition of MAlx alloys (M = Co, Ni, Fe, Cu, and Ag) electrodeposited from 1.5:1.0 AlCl3:1-ethyl-3-methylimidazolium chloride room temperature ionic liquids. The analysis method relied on the fact that these alloys are produced by an underpotential deposition mechanism. Results were consistent with previous studies showing that the CoAlx, FeAlx, and CuAlx systems tended to produce alloys with x approximate to 1. Analysis of the NiAlx data was complicated by kinetic phenomena, while data analysis of the AgAlx system was precluded by dendritic growth of the electrodeposit. All the alloy systems showed complex anodic stripping voltammetric behavior, and the nature of the oxidation processes (e.g., metal anodization, alloy anodization, or selective dealloying) are different for electrodeposits produced in specific potential regimes. Nonlinear curve fitting of the chronoamperometric data to the appropriate short-time and long-time equations gave diffusion coefficients from 3.9 x 10(-7) to 8.3 x 10(-7) cm(2) s(-1) for the transition metal ions in the ionic liquid electrolyte at ca. 22 degrees C. C1 Off Naval Res, Arlington, VA 22217 USA. USN, Res Lab, Div Chem, Washington, DC 20332 USA. RP Carlin, RT (reprint author), Off Naval Res, Arlington, VA 22217 USA. NR 36 TC 52 Z9 54 U1 0 U2 22 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 MAY PY 1998 VL 145 IS 5 BP 1598 EP 1607 DI 10.1149/1.1838524 PG 10 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZJ387 UT WOS:000073209800033 ER PT J AU Gu, XH Korotkov, RY Ding, YJJ Kang, JU Khurgin, JB AF Gu, XH Korotkov, RY Ding, YJJ Kang, JU Khurgin, JB TI Backward second-harmonic generation in periodically poled lithium niobate SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID 2ND-HARMONIC GENERATION; QUANTUM-WELLS AB For periodically poled LiNbO3 with a 3.3-mu m domain period we observed backward second-harmonic generation using nanosecond laser pulses. We measured phase-matching spectra at the 16th, 17th, 18th, 19th, and 20th orders of the spatial grating. The peak wavelength of each order is in good agreement with the theoretical prediction. The quadratic dependence of the backward second-harmonic output pulse energy on the pump pulse energy was confirmed in our experiments. The quadratic dependence of the conversion efficiency on the domain length was also confirmed. Using nanosecond pulses, we achieved a maximum conversion efficiency of 0.296% for the 16th-order grating. (C) 1998 Optical Society of America [S0740-3224(98)02305-4]. C1 Bowling Green State Univ, Dept Phys & Astron, Bowling Green, OH 43403 USA. Bowling Green State Univ, Ctr Photochem Sci, Bowling Green, OH 43403 USA. Bowling Green State Univ, Ctr Mat Sci, Bowling Green, OH 43403 USA. USN, Res Lab, Washington, DC 20375 USA. Johns Hopkins Univ, Dept Elect & Comp Engn, Baltimore, MD 21218 USA. RP Gu, XH (reprint author), Bowling Green State Univ, Dept Phys & Astron, Bowling Green, OH 43403 USA. RI Kang, Jin/A-3228-2010; khurgin, Jacob/A-3278-2010 NR 15 TC 40 Z9 40 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 1998 VL 15 IS 5 BP 1561 EP 1566 DI 10.1364/JOSAB.15.001561 PG 6 WC Optics SC Optics GA ZM955 UT WOS:000073593200016 ER PT J AU Yater, JE Shih, A Abrams, R AF Yater, JE Shih, A Abrams, R TI Electron transport and emission properties of diamond SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 44th American-Vacuum-Society Symposium on Flat Panel Displays, Micromechanical Systems, and Quantitative Surface and Analysis CY OCT 20-24, 1997 CL SAN JOSE, CALIFORNIA SP Amer Vacuum Soc ID AFFINITY; SURFACE; CATHODES AB The electron transport and emission properties of hydrogenated and cesiated single-crystal and chemical-vapor-deposited (CVD) diamond are investigated using secondary electron emission spectroscopy. The kinetic energy of the electrons and the height of the surface energy barrier are measured relative to the conduction band minimum, E-c, which is identified in the spectra. In spectra measured from hydrogenated and cesiated diamond surfaces, electron emission appears at energies E < E-c which gives direct evidence of a negative electron affinity. The strongest emission is observed from cesiated samples, which produced very high yields (delta(max) similar to 80-130 at E-b = 2900 eV). The energy distributions from all three samples are sharply peaked at similar to 0.50-0.65 eV above E-c and have a full width at half maximum similar to 0.55-0.75 eV, except in the case of the cesiated CVD diamond samples. The energy distributions measured from cesiated CVD diamond are peaked at lower energy and are much broader due to lower emission-onset energies. An emission model, which invokes band bending near the surface, is deduced that accounts for the observed energy spectra from the samples in terms of the surface properties of the C(100) and CVD diamond and the internal electron energy distributions. C1 USN, Res Lab, Washington, DC 20375 USA. RP Yater, JE (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 19 TC 20 Z9 20 U1 1 U2 1 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 MAY-JUN PY 1998 VL 16 IS 3 BP 913 EP 918 DI 10.1116/1.581210 PN 1 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA ZT991 UT WOS:000074150400002 ER PT J AU Jung, DR Cuttino, DS Pancrazio, JJ Manos, P Cluster, T Sathanoori, RS Aloi, LE Coulombe, MG Czamaski, MA Borkholder, DA Kovacs, GTA Bey, P Stenger, DA Hickman, JJ AF Jung, DR Cuttino, DS Pancrazio, JJ Manos, P Cluster, T Sathanoori, RS Aloi, LE Coulombe, MG Czamaski, MA Borkholder, DA Kovacs, GTA Bey, P Stenger, DA Hickman, JJ TI Cell-based sensor microelectrode array characterized by imaging x-ray photoelectron spectroscopy, scanning electron microscopy, impedance measurements, and extracellular recordings SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 44th American-Vacuum-Society Symposium on Flat Panel Displays, Micromechanical Systems, and Quantitative Surface and Analysis CY OCT 20-24, 1997 CL SAN JOSE, CALIFORNIA SP Amer Vacuum Soc ID CULTURE; GROWTH AB We are developing a cell-based biosensor consisting of a planar microelectrode array that allows detection of extracellular potentials and their modulation in the presence of toxins or other active agents. To improve cell-electrode coupling, the microelectrodes were electroplated with platinum black. We report on the use of imaging x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), impedance measurements, and extracellular recordings to assess the effectiveness of this procedure. SEM provided highly detailed images of the shape and structure of well-formed deposits of thickness on the order of 1 mu m or more. Because of its inherent high surface sensitivity, imaging XPS could reveal the presence of platinum deposits that were too thin to be detected by SEM. For typical, well-plated microelectrodes, impedance measurements showed reductions in the electrical resistance at 100 Hz from roughly 60 M Ohm or more 1 M Ohm. The overall electronic coupling of biopotentials to the microelectrodes was demonstrated by recordings obtained from beating rat myocytes and from rat spinal cord cells. (C) 1998 American Vacuum Society. [S0734-2101(98)06403-3]. C1 Sci Applicat Int Corp, Biotechnol Res & Applicat Div, Rockville, MD 20850 USA. Sci Applicat Int Corp, Appl Phys Operat, Mclean, VA 22102 USA. Stanford Univ, Dept Elect Engn, Stanford, CA 94305 USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Hickman, JJ (reprint author), George Washington Univ, Dept Chem, Washington, DC 20052 USA. RI Pancrazio, Joseph/M-3206-2015 OI Pancrazio, Joseph/0000-0001-8276-3690 NR 21 TC 32 Z9 33 U1 1 U2 3 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 MAY-JUN PY 1998 VL 16 IS 3 BP 1183 EP 1188 DI 10.1116/1.581256 PN 1 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA ZT991 UT WOS:000074150400055 ER PT J AU Freeland, JW Chakarian, V Idzerda, YU Doherty, S Zhu, JG Wende, H Kao, CC AF Freeland, JW Chakarian, V Idzerda, YU Doherty, S Zhu, JG Wende, H Kao, CC TI Directly identifying the order of layer switching in magnetic multilayers SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 44th American-Vacuum-Society Symposium on Flat Panel Displays, Micromechanical Systems, and Quantitative Surface and Analysis CY OCT 20-24, 1997 CL SAN JOSE, CALIFORNIA SP Amer Vacuum Soc ID RESONANCE EXCHANGE SCATTERING; CIRCULAR-DICHROISM; COBALT; EDGES; FILMS; IRON; CO AB The determination of the order of layer switching for two different technologically interesting multilayer systems, NiFe/Cu/Co and Co/Cr/Co, is accomplished by monitoring changes in the angular dependence of the magnetic contributions to the soft x-ray resonant magnetic scattering asa function of applied field. (C) 1998 American Vacuum Society. [S0734-2101(98)06603-2]. C1 USN, Res Lab, Washington, DC 20375 USA. Carnegie Mellon Univ, DSSC, Pittsburgh, PA 15213 USA. Free Univ Berlin, D-14195 Berlin, Germany. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. RP Freeland, JW (reprint author), NRL, NSLS Bldg 725A-4UB, Upton, NY 11973 USA. EM freeland@bnlls3.nsls.bnl.gov RI Wende, Heiko/J-8505-2012 NR 21 TC 3 Z9 3 U1 0 U2 1 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 MAY-JUN PY 1998 VL 16 IS 3 BP 1355 EP 1358 DI 10.1116/1.581150 PN 1 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA ZT991 UT WOS:000074150400086 ER PT J AU Leonhardt, D Eddy, CR Shamamian, VA Holm, RT Glembocki, OJ Butler, JE AF Leonhardt, D Eddy, CR Shamamian, VA Holm, RT Glembocki, OJ Butler, JE TI Surface chemistry and damage in the high density plasma etching of gallium arsenide SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 44th National Symposium of the American-Vacuum-Society CY OCT 20-24, 1997 CL SAN JOSE, CALIFORNIA SP Amer Vacuum Soc ID FRANZ-KELDYSH OSCILLATIONS; MODULATION SPECTROSCOPY; GAAS; PHOTOREFLECTANCE; TEMPERATURE AB Anisotropic pattern transfer with low damage in compound semiconductor dry etching requires an in depth understanding of the chemical processes that occur at the plasma/semiconductor interface that promote the removal of volatile product species. In situ mass spectrometry has been used to study product evolution during high density plasma etching of GaAs in a Cl-2/Ar chemistry. Through definitive surface temperature control and configuration of the mass spectrometer to sample through the substrate platen, a comprehensive picture of the etch process was obtained. Evolution of etch products of GaAs (AsClx and GaClx) was monitored as neutral flux (pressure), ion flux (microwave power) and ion energy (substrate bias) are varied to identify conditions where ion-driven surface chemistry is dominant. Observations show that fluxes of atomic chlorine neutrals and ions are required at the substrate to maximize etch product formation. These conditions are optimally met at low microwave powers (less than or equal to 300 W) and pressures (less than or equal to 1.0 mTorr) in our system. The ion energy. dependence of product formation shows regions of thermal/chemical etching for energies less than 50 eV, ion-assisted chemical etching for energies between 50 and 200 eV, and sputtering for energies greater than 200 eV. Ideal processing conditions are ascertained from the trade off between maximum ion-assisted etch rate and minimal electronic damage, as measured by photoreflectance spectrometry. The effectiveness of post-etch chlorine treatments on returning of the surface Fermi level to its pre-etched value was also investigated. (C) 1998 American Vacuum Society. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Leonhardt, D (reprint author), USN, Res Lab, Div Chem, Code 6174, Washington, DC 20375 USA. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 19 TC 7 Z9 7 U1 1 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 MAY-JUN PY 1998 VL 16 IS 3 BP 1547 EP 1551 DI 10.1116/1.581185 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA ZT992 UT WOS:000074150500028 ER PT J AU Grunthaner, FJ Bicknell-Tassius, R Deelman, P Grunthaner, PJ Bryson, C Snyder, E Giuliani, JL Apruzese, JP Kepple, P AF Grunthaner, FJ Bicknell-Tassius, R Deelman, P Grunthaner, PJ Bryson, C Snyder, E Giuliani, JL Apruzese, JP Kepple, P TI Ultrahigh vacuum arcjet nitrogen source for selected energy epitaxy of group III nitrides by molecular beam epitaxy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 44th National Symposium of the American-Vacuum-Society CY OCT 20-24, 1997 CL SAN JOSE, CALIFORNIA SP Amer Vacuum Soc ID PLASMA SOURCE; GROWTH; FILMS; GAN AB The key technical challenge in the molecular beam epitaxial (MBE) growth of group III nitrides is the lack of a suitable source of incorporatable nitrogen. In contrast with the growth of the other III-V compound semiconductors by MBE, direct reaction of N-2 with excess group III metal is not feasible, because of the high bond strength of dinitrogen. An incorporatable MBE nitrogen source must excite N-2 forming a beam of atomic nitrogen, active nitrogen (N-2(*)), or nitrogen ions. rf and electron cyclotron resonance sources use electron impact excitation to obtain atomic nitrogen and in the process generate a wide variety of excited ions and neutrals. Experiments have shown that ionic species in the beam degrade the morphology of the epitaxial layer and generate electrically active defects. Recent theoretical studies have predicted that ground state atomic nitrogen will successfully incorporate into the growing GaN surface, while atomic nitrogen in either of the excited doublet states will lead to etching. In this article, we report on the development of an ultrahigh vacuum-compatible arcjet source which uses an electric are to thermally dissociate N-2. The thermal excitation mechanism offers selective excitation of nitrogen and control of kinetic energy of the active species. This source has been fabricated from refractory materials and uses two stages of differential pumping to minimize the pressure in the growth chamber. The arcjet has been reliably operated at power levels of 10-300 W, with no visible degradation of the thoriated tungsten cathode after 300 h. No metal contaminant lines can be found in the optical emission spectrum. Using an Ar-seeded beam for calibration of the optical spectrum, we find that the arcjet plasma is far from local thermodynamic equilibrium, and show that the fraction of atomic nitrogen in the beam ranges from 0.3% to 9%. This corresponds to a flux of 0.1-4 monolayers per second at the MBE sample location. With an articulated Langmuir probe sampling the beam at the MBE growth position, we find a positive ion flux of less than 4X10(-9) A/cm(2), a maximum ion kinetic energy of 3.5 eV, a median electron energy of 1 eV, and a maximum electron energy of less than 4 eV. With increasing arcjet power, the ion and electron fluxes increase and the ion energy distribution shifts to lower energies. No change in the electron spectrum is observed. Quadrupole mass spectra of the ion flux measured on the arcjet axis show that the N+/N-2(+) ratio has a maximum at an arcjet power of about 35 W. (C) 1998 American Vacuum Society. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Surface Interface Inc, Sunnyvale, CA 94086 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Grunthaner, FJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Frank.J.Grunthaner@JPL.NASA.gov NR 17 TC 14 Z9 14 U1 1 U2 6 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 MAY-JUN PY 1998 VL 16 IS 3 BP 1615 EP 1620 DI 10.1116/1.581129 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA ZT992 UT WOS:000074150500040 ER PT J AU Erickson, JW Sheng, J Gao, Y Pham, H Singer, IL AF Erickson, JW Sheng, J Gao, Y Pham, H Singer, IL TI Carbon overcoat composition and structure analysis by secondary ion mass spectrometry SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 44th National Symposium of the American-Vacuum-Society CY OCT 20-24, 1997 CL SAN JOSE, CALIFORNIA SP Amer Vacuum Soc ID FILMS; DEPOSITION; CNX AB The composition and structure of carbon overcoat layers on hard discs were studied systematically using secondary ion mass spectrometry (SIMS). The amounts of H, C, N, and O in the carbon overcoat were measured along with Co and Cr outdiffusion from the underlying magnetic layer. Two SIMS techniques were used, the "MCs+" technique in which the secondary ion intensity is linearly proportional to the concentration [M], and the "M2M3" technique in which the secondary ion intensities show quadratic and cubic dependence on [M]. The MCs+ technique was used to measure stoichiometry and thus characterize diamond-like carbon, hydrogenated carbon, and carbon nitride overcoat layers or sublayers. The M2M3 technique was used to provide structural information on the physical uniformity of the overcoat. The SIMS results are compared to those from other techniques, emphasizing the relative value and cost of information. The tribological issues affecting hard disc durability and wear are discussed. (C) 1998 American Vacuum Society. C1 Charles Evans & Associates, Redwood City, CA 94063 USA. StorMedia, Santa Clara, CA USA. USN, Res Lab, Washington, DC 20375 USA. RP Erickson, JW (reprint author), Charles Evans & Associates, Redwood City, CA 94063 USA. NR 17 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 MAY-JUN PY 1998 VL 16 IS 3 BP 1750 EP 1756 DI 10.1116/1.581296 PN 2 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA ZT992 UT WOS:000074150500065 ER PT J AU Johnson, M AF Johnson, M TI Hybrid ferromagnet-semiconductor devices SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 44th National Symposium of the American-Vacuum-Society CY OCT 20-24, 1997 CL SAN JOSE, CALIFORNIA SP Amer Vacuum Soc ID PARTICLES AB Novel magnetoelectronic devices for application as nonvolatile memory cells, logic gates, or magnetic field sensors are based on a bilayer structure comprised of a high mobility semiconducting Hall cross and a single, electrically isolated, microstructured ferromagnetic film. Prototypes have been fabricated at the micron and sub-micron size scale. The device state is determined by the bistable magnetic state of the ferromagnetic element, and the two corresponding output states can be symmetrically bipolar or HIGH (order of tens of ohms) and LOW (approximately zero). Fabrication involves two Lithographic steps, a mesa etch of the semiconductor and a patterning of the ferromagnetic film. Atomic force microscope and magnetic force microscope images are used to correlate the effects of processing on the micromagnetism of the ferromagnetic component and the device output characteristics. Early prototype device sets have been fabricated using high mobility indium arsenide layers for the Hall element, but the concept is compatible with silicon technology. The device demonstrates inverse scalability: output levels increase as the device dimensions decrease. C1 USN, Res Lab, Washington, DC 20375 USA. RP Johnson, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 15 TC 18 Z9 18 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1998 VL 16 IS 3 BP 1806 EP 1811 DI 10.1116/1.581111 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA ZT992 UT WOS:000074150500076 ER PT J AU Kobayashi, N Herrman, MN Johnson, BD Orzech, MD AF Kobayashi, N Herrman, MN Johnson, BD Orzech, MD TI Probability distribution of surface elevation in surf and swash zones SO JOURNAL OF WATERWAY PORT COASTAL AND OCEAN ENGINEERING LA English DT Article ID NATURAL BEACH; WAVE TRANSFORMATION; RUN-UP; BREAKING; SETUP AB Three irregular wave tests were conducted on a 1:16 smooth impermeable slope to investigate the detailed cross-shore variations of the probability distributions and statistics of the free surface elevations and middepth horizontal velocities in the shoaling, surf, and swash zones. The exponential gamma distribution with the measured mean, standard deviation, and skewness is shown to be capable of describing the measured probability distributions in a unified manner, although the agreement becomes worse in the lower swash zone. The probability distribution of the free surface elevation whose lower limit is imposed by the beach face in the swash zone becomes exponential with the skewness s = 2 and the standard deviation sigma = (h) over bar with (h) over bar = mean water depth. These upper limits of s and sigma/h in the lower swash zone are in qualitative agreement with the data in the region of (h) over bar greater than or similar to 0.4 cm in these small-scale tests. The cross-shore variations of the mean (undertow) and standard deviation of the middepth horizontal velocity measured in the shoaling and surf zones can be predicted fairly accurately using the simple relationships derived using linear long-wave theory together with the measured values of (h) over bar and sigma. The adopted distribution and these simple relationships will need to be verified using extensive data on sand beaches of various profiles. C1 Univ Delaware, Ctr Appl Coast Res, Oc Engrg Lab, Newark, DE 19716 USA. Moffatt & Nichol, Baltimore, MD 21224 USA. Univ Delaware, Dept Civil & Environm Engn, Newark, DE 19716 USA. USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Univ Delaware, Ctr Appl Coast Res, Oc Engrg Lab, Newark, DE 19716 USA. NR 39 TC 21 Z9 21 U1 2 U2 2 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-950X EI 1943-5460 J9 J WATERW PORT COAST JI J. Waterw. Port Coast. Ocean Eng. PD MAY-JUN PY 1998 VL 124 IS 3 BP 99 EP 107 DI 10.1061/(ASCE)0733-950X(1998)124:3(99) PG 9 WC Engineering, Civil; Engineering, Ocean; Water Resources SC Engineering; Water Resources GA ZJ392 UT WOS:000073210400001 ER PT J AU Kwon, YW Liu, CT AF Kwon, YW Liu, CT TI Damage growth in a particulate composite under a high strain rate loading SO MECHANICS RESEARCH COMMUNICATIONS LA English DT Article ID FIBROUS COMPOSITES C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. Phillips Lab, Edward AFB, CA 93524 USA. RP Kwon, YW (reprint author), USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. NR 9 TC 6 Z9 6 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0093-6413 J9 MECH RES COMMUN JI Mech. Res. Commun. PD MAY-JUN PY 1998 VL 25 IS 3 BP 329 EP 336 DI 10.1016/S0093-6413(98)00045-7 PG 8 WC Mechanics SC Mechanics GA ZP496 UT WOS:000073759300014 ER PT J AU Woodhead, AB AF Woodhead, AB TI A new wellness center concept: Integration of the physical therapy and the morale, welfare, and recreation departments SO MILITARY MEDICINE LA English DT Article AB This case study describes the implementation of a wellness center based on the integration of a Navy outpatient physical therapy department and a morale, welfare, and recreation cardiovascular center. The logistics and services provided are discussed. The productivity of the physical therapy department based on the monthly number of patient treatments is assessed. A statistically significant increase in patient visits of 38% above the previous year was noted. The newly established cardiovascular center averaged 1,500 client visits monthly. This unique collaboration appears to hold promise as an effective wellness center concept. C1 USN Hosp, Phys Therapy Dept, Pensacola, FL 32512 USA. RP Woodhead, AB (reprint author), USN Hosp, Phys Therapy Dept, Pensacola Highway 98W, Pensacola, FL 32512 USA. NR 7 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 MAY PY 1998 VL 163 IS 5 BP 307 EP 309 PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA ZM692 UT WOS:000073566300009 PM 9597847 ER PT J AU Goerss, JS Velden, CS Hawkins, JD AF Goerss, JS Velden, CS Hawkins, JD TI The impact of multispectral GOES-8 wind information on Atlantic tropical cyclone track forecasts in 1995. Part II: NOGAPS forecasts SO MONTHLY WEATHER REVIEW LA English DT Article ID ATMOSPHERIC PREDICTION SYSTEM; QUALITY-CONTROL; IMPROVEMENTS; SCHEME; MODEL AB Experimental wind datasets were derived for two time periods (13-20 July and 24 August-10 September 1995) from GOES-8 observations processed at the University of Wisconsin Cooperative institute for Meteorological Satellite Studies (UW CIMSS). The first dataset was focused on Tropical Storm Chantal, and the second dataset was focused on the multiple-storm environment that included Hurricanes Humberto, Iris, and Luis. Both datasets feature a processing and quality control strategy designed to optimize the quantity and content of geostationary satellite-derived winds in the vicinity of tropical cyclones. Specifically, the winds were extracted from high-density targets obtained from multispectral imagery, which included three water vapor bands (6.7, 7.0, and 7.3 mu m), infrared, and visible. The Navy Operational Global Atmospheric Prediction System (NOGAPS) was used as the vehicle to determine the impact of these winds upon tropical cyclone track forecasts. During the 1995 Atlantic hurricane season the NOGAPS forecasts were found to be quite skillful, displaying relative improvement of tropical cyclone position error with respect to CLIPER (climate and persistence) of 20% at 24 h, 35% at 48 h, and 33% at 72 h. The NOGAPS data assimilation system was run with and without the high density GOES-8 winds for the two aforementioned time periods. The assimilation of these winds resulted in significant improvements in the NOGAPS forecasts for Tropical Storm Chantal and Hurricane Iris and mixed results for Hurricanes Humberto and Luis. Overall, for all four cyclones, tie NOGAPS forecasts made with the use of the UW CIMSS winds displayed relative improvement of forecast position error with respect to those made without the use of the UW CIMSS winds of 14% at 24 h, and 12% at both 48 and 72 h. C1 USN, Res Lab, Monterey, CA 93943 USA. Univ Wisconsin, Cooperat Inst Meteorol Satellite Studies, Madison, WI USA. RP Goerss, JS (reprint author), USN, Res Lab, 7 Grace Hopper Ave,Stop 2, Monterey, CA 93943 USA. NR 18 TC 54 Z9 60 U1 0 U2 1 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 MAY PY 1998 VL 126 IS 5 BP 1219 EP 1227 DI 10.1175/1520-0493(1998)126<1219:TIOMGW>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZL980 UT WOS:000073492800009 ER PT J AU Miller, LH Hoffman, SL AF Miller, LH Hoffman, SL TI Research toward vaccines against malaria SO NATURE MEDICINE LA English DT Review ID PLASMODIUM-FALCIPARUM; PROTECTIVE IMMUNITY; VACCINATION; PROTEINS; PEPTIDE; DOMAINS; IDENTIFICATION; ERYTHROCYTES; INDUCTION; EFFICACY C1 NIAID, Parasit Dis Lab, NIH, Bethesda, MD 20892 USA. USN, Med Res Inst, Malaria Program, Bethesda, MD 20889 USA. RP Miller, LH (reprint author), NIAID, Parasit Dis Lab, NIH, Bethesda, MD 20892 USA. EM louis_miller@nih.gov NR 40 TC 87 Z9 87 U1 0 U2 1 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1078-8956 J9 NAT MED JI Nat. Med. PD MAY PY 1998 VL 4 IS 5 SU S BP 520 EP 524 DI 10.1038/nm0598supp-520 PG 5 WC Biochemistry & Molecular Biology; Cell Biology; Medicine, Research & Experimental SC Biochemistry & Molecular Biology; Cell Biology; Research & Experimental Medicine GA ZL625 UT WOS:000073453500021 PM 9585203 ER PT J AU Griscom, DL Merzbacher, CI Bibler, NE Imagawa, H Uchiyama, S Namiki, A Marasinghe, GK Mesko, M Karabulut, M AF Griscom, DL Merzbacher, CI Bibler, NE Imagawa, H Uchiyama, S Namiki, A Marasinghe, GK Mesko, M Karabulut, M TI On the structure and radiation chemistry of iron phosphate glasses: New insights from electron spin resonance, Mossbauer, and evolved gas mass spectroscopy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 9th International Conference on Radiation Effects in Insulators (REI-9) CY SEP 14-19, 1997 CL KNOXVILLE, TENNESSEE SP Ctr Mat Proc at Univ TN, Pacific NW Natl Lab DE nuclear waste glasses; electron spin resonance; iron phosphate glasses; radiation effects; gamma rays; glass structure; Mossbauer; mass spectrometry ID DEFECT AB Several vitreous forms for immobilization of plutonium and/or high-level nuclear wastes have been surveyed by electron spin resonance (ESR) to gain insights into their atomic-scale structures and to look for signs of radiolytic decomposition resulting from exposures to gamma-ray doses of 30 MGy. While preliminary results are reported for Defense Waste Processing Facility (DWPF) borosilicate compositions and an experimental lanthanum-silicate glass, this paper focusses primarily on a class of glasses containing 40-75 mol% P2O5 and up to 40 mol% Fe2O3. Each of the six diverse compositions investigated displayed characteristic ESR signals (not resembling those of the iron-containing phosphorus-free glasses) comprising combinations of an extremely broad "X resonance" and a narrow "Z resonance", both centered near g = 2.00 and both displaying nearly perfect Lorentzian line shapes (peak-to-peak derivative widths similar to 300-600 mT and similar to 30 mT, respectively, at 300 K). The X-resonance intensities in the air-melted glasses correlated linearly with Fe:P ratio up to [Fe2O3]/[P2O5] approximate to 0.6, where intensity values similar to 1 spin/phosphorus were reached. Mossbauer studies showed that the [Fe3+]/[Fe](tot) ratio could be varied from 0.82 to 0.49 by raising the melting temperature in air from 1150 degrees C to 1450 degrees C and/or by employing mildly reducing atmospheres. The combined X + Z-resonance intensities were reduced to zero for [Fe3+]/[Fe](tot) less than similar to 0.6, leaving only a much weaker spectrum attributable to Fe3+ ions. The X and Z ESR signals of the iron phosphate glasses resemble nothing else in the literature except the correspondingly denoted signals in an iron;free amorphous peroxyborate (APB) preparation. The X and Z resonances in the latter are deemed to arise from superoxide ions (O-2(-)) in the berate network and in a separated Na2O2 phase, respectively. An asymmetric Z resonance signal attributable to interstitial 0; species was a radiation-induced manifestation in phosphate glass of composition 50P(2)O(5)-20Fe(2)O(3)-23Li(2)O-7CeO(2). Irradiated and unirradiated samples of this same glass were studied by ESR isochronal annealing and differential thermal analysis, revealing a one-for-one conversion of X to Z upon partial crystallization near 670 degrees C and a Z --> X reconversion upon partial remelting near 970 degrees C. Heating to 1070 degrees C in dry Ar resulted in a weight loss of similar to 5 wt%, while quadrupole mass spectrometry (QMS) during ramped heating to 1550 degrees C at a pressure of 10(-5) Pa revealed the evolution of Oz molecules with (radiation sensitive) ion-current peaks near 1170 degrees C and 1350-1400 degrees C. To account for the totality of these and other results, it is suggested that air-melted lion phosphate glasses may contain macroscopic numbers of superoxide ions as an intrinsic chemical feature of their as-quenched structures. A specific four-connected phosphorus-oxygen glass network incorporating O-2(-) ions is proposed, (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Westinghouse Savannah River Co, Aiken, SC 29808 USA. Toyo Univ, Kawagoe, Saitama 350, Japan. Univ Missouri, Rolla, MO 65409 USA. RP Griscom, DL (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 20 TC 11 Z9 11 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1998 VL 141 IS 1-4 BP 600 EP 615 DI 10.1016/S0168-583X(98)00149-9 PG 16 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 103WA UT WOS:000074979800105 ER PT J AU LoPresti, JL Webb, SC Williams, RT Kim, W Morkoc, H Wickenden, AE Koleske, DD AF LoPresti, JL Webb, SC Williams, RT Kim, W Morkoc, H Wickenden, AE Koleske, DD TI Study of GaN films by pulsed laser photoelectron spectroscopy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 9th International Conference on Radiation Effects in Insulators (REI-9) CY SEP 14-19, 1997 CL KNOXVILLE, TENNESSEE SP Ctr Mat Proc at Univ TN, Pacific NW Natl Lab DE gallium nitride; photoelectron; femtosecond; hot electrons; conduction band; surface defects ID SURFACES AB We have studied surface defect states and conduction electrons in molecular-beam epitaxy (MBE)-grown and metalorganic vapor phase epitaxy (MOVPE)-grown GaN films using the third and fourth harmonics of a Ti:sapphire pulsed laser to excite photoelectrons by one- and two-photon transitions. By introducing a delay between the excitation and probe pulses in two-step excitations it is possible to measure the intermediate state lifetimes. Spectra of occupied surface defect states in the gap of n-type GaN are reported. Under intense photon pumping, conduction electron spectra are observed. The relaxation time of hot carriers in the conduction band is less than 200 fs. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA. Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. Univ Illinois, Coordinated Sci Lab, Urbana, IL 61801 USA. USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RP LoPresti, JL (reprint author), Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA. NR 9 TC 2 Z9 2 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1998 VL 141 IS 1-4 BP 733 EP 736 DI 10.1016/S0168-583X(98)00123-2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 103WA UT WOS:000074979800125 ER PT J AU Jarrett, M Heitkemper, M Cain, KC Tuftin, M Walker, EA Bond, EF Levy, RL AF Jarrett, M Heitkemper, M Cain, KC Tuftin, M Walker, EA Bond, EF Levy, RL TI The relationship between psychological distress and gastrointestinal symptoms in women with irritable bowel syndrome SO NURSING RESEARCH LA English DT Article DE irritable bowel syndrome; psychological distress; women ID DIAGNOSTIC INTERVIEW SCHEDULE; MENSTRUAL-CYCLE; PSYCHIATRIC-DISORDERS; PANIC DISORDER; LIFE EVENTS; PREVALENCE; EPIDEMIOLOGY; COMPLAINTS; ANXIETY; ILLNESS AB Background: Individuals with irritable bowel syndrome (IBS) are reported to experience more symptoms compatible with psychopathologic disorders, abnormal personality traits, and psychological distress. Conversely, individuals with psychiatric disorders report higher levels of gastrointestinal (GI) symptoms compatible with IBS. Thus, psychological distress may contribute to GI symptoms in individuals with IBS. Objectives: To examine psychological distress in women with IBS, women with similar GI symptoms but not diagnosed (IBS nonpatients, IBS-NP), and asymptomatic Control women. Methods: The women (N = 97) were interviewed, completed questionnaires, and maintained daily diaries for 2 months. Across-women and within-woman analyses were used to calculate the results. Results: The IBS and IBS-NP groups had a higher percentage of lifetime psychopathology and recalled psychological distress. At least 40% of the women in the IBS and IBS-NP groups had positive relationships between daily psychological distress and daily GI symptoms. Conclusions: Psychological distress is an important component of the IBS symptom experience and should be considered when treatment strategies are designed. C1 Univ Washington, Dept Biobehav Nursing & Hlth Syst, Seattle, WA 98195 USA. Univ Washington, Dept Biostat, Seattle, WA 98195 USA. Univ Washington, Dept Psychiat & Behav Sci, Seattle, WA 98195 USA. Univ Washington, Sch Social Work, Seattle, WA 98195 USA. USN, San Diego, CA 92152 USA. RP Jarrett, M (reprint author), Univ Washington, Dept Biobehav Nursing & Hlth Syst, Box 357266, Seattle, WA 98195 USA. FU NINR NIH HHS [NR01-01094] NR 44 TC 31 Z9 31 U1 1 U2 3 PU AMER J NURSING CO PI NEW YORK PA 555 W 57TH ST, NEW YORK, NY 10019-2961 USA SN 0029-6562 J9 NURS RES JI Nurs. Res. PD MAY-JUN PY 1998 VL 47 IS 3 BP 154 EP 161 DI 10.1097/00006199-199805000-00006 PG 8 WC Nursing SC Nursing GA ZN358 UT WOS:000073637900005 PM 9610649 ER PT J AU Forsnes, EV Eggleston, MK Wax, JR AF Forsnes, EV Eggleston, MK Wax, JR TI Differential transmission of adenovirus in a twin pregnancy SO OBSTETRICS AND GYNECOLOGY LA English DT Article ID POLYMERASE CHAIN-REACTION; INFECTION; MYOCARDITIS; DIAGNOSIS AB Background: Intrauterine adenovirus infection has been associated with nonimmune hydrops. We describe a twin pregnancy in which adenovirus was demonstrated by polymerase chain reaction in the amniotic fluid of one twin afflicted by hydrops. Adenovirus was absent in the amniotic fluid of the other twin. Case: A 25-year-old, gravida 3, para 1, with twin gestation at 20 weeks' gestation was noted on ultrasound anomaly screen to have hydrops associated with twin B. Polymerase chain reaction analysis of amniotic fluid revealed adenovirus in twin B with none noted in twin A. At 26 weeks' gestation both infants died. Conclusion: This case demonstrates differential transmission of adenovirus in a twin pregnancy. One twin developed hydrops fetalis possibly secondary to adenovirus infection. C1 Naval Med Ctr, Dept Obstet & Gynecol, Div Maternal Fetal Med, Portsmouth, VA USA. RP Forsnes, EV (reprint author), Naval Hosp, Dept Obstet & Gynecol, Code 43,POB 10100, Camp Lejeune, NC 28547 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0029-7844 J9 OBSTET GYNECOL JI Obstet. Gynecol. PD MAY PY 1998 VL 91 IS 5 SU S BP 817 EP 818 DI 10.1016/S0029-7844(97)00468-7 PN 2 PG 2 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA ZK329 UT WOS:000073308200010 PM 9572173 ER PT J AU Rajagopal, AK AF Rajagopal, AK TI Equations of motion in nonequilibrium statistical mechanics for nonextensive systems SO PHYSICA A LA English DT Article ID DEPENDENT VARIATIONAL PRINCIPLE; INTRINSIC DECOHERENCE; DYNAMICAL SEMIGROUPS; QUANTUM-MECHANICS; COHERENT STATES; TSALLIS AB Recent investigations of nanoscale quantum device systems and small clusters of atoms and molecules have shown new features of both nonequilibrium dynamics and nonextensivity. The challenge is to understand theoretically the fast dynamical processes on time scales of femtoseconds in these systems. An overview of the approaches to time-dependent nonequilibrium statistical mechanics, including a critical review of the entropic methods due to Jaynes, Robertson, and Zubarev for the extensive nonequilibrium systems, reveals difficulties in setting up the associated dynamics. We therefore propose the use of the Lindblad equation for the density matrix in place of the usual unitary Liouville-von Neumann equation of motion because it meets all the required criteria (positive, trace-class, and includes the possibility of mixed to pure state evolution) for describing dissipative dynamics and the T sallis prescription for handling the nonextensivity. We will explore briefly (i) the notion of decoherence, (ii) near equilibrium linear response, (iii) evolution of entropy, and (iv) action principle, based on these considerations. Pie also exhibit a time-dependent "mixed state" marker for describing the nonequilibrium state of a dissipative quantum oscillator, which is a prototype of an electronic device. This investigation, it is hoped, gives glimpses of insight into understanding the short time-scale dynamics of systems between the times determined by the uncertainty principle and the decoherence clue to the heat bath. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rajagopal, AK (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM rajagopal@estd.nr1.navy.mil NR 33 TC 7 Z9 7 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD MAY 1 PY 1998 VL 253 IS 1-4 BP 271 EP 289 DI 10.1016/S0378-4371(98)00031-4 PG 19 WC Physics, Multidisciplinary SC Physics GA ZY333 UT WOS:000074609900022 ER PT J AU Carr, TW Schwartz, IB AF Carr, TW Schwartz, IB TI On measures of disorder in globally coupled oscillators SO PHYSICA D LA English DT Article DE coupled oscillators; disorder; coherence ID JUNCTION SERIES ARRAYS; PHASE-TRANSITION; JOSEPHSON; SYNCHRONIZATION; STABILITY; DYNAMICS; STATES; MODEL AB The transition from ordered to disordered behavior in an array of globally coupled phase oscillators is studied here using methods previously applied to the study of fluid turbulence. We apply a biorthogonal decomposition of the "space"-time data signal resulting from a finite sized array of oscillators under increasing disorder. Application of these methods requires identifying and measuring a useful signal that captures the dynamics of interest. We find that our method is very sensitive to changes in the system as a function of the disorder and identifies when an oscillator loses entrainment with the population. We study finite sized systems and simultaneously compare our results to more traditional order parameters, the latter based on infinite sized systems. Copyright (C) 1998 Elsevier Science B.V. C1 So Methodist Univ, Dept Math, Dallas, TX 75275 USA. USN, Res Lab, Special Project Nonlinear Sci, Div Plasma Phys, Washington, DC 20375 USA. RP Carr, TW (reprint author), So Methodist Univ, Dept Math, Dallas, TX 75275 USA. EM carr@aeolus.math.smu.edu; schwartz@nls4.nrl.navy.mil RI Schwartz, Ira/A-8073-2009 NR 26 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD MAY 1 PY 1998 VL 115 IS 3-4 BP 321 EP 340 DI 10.1016/S0167-2789(97)00238-8 PG 20 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA ZJ663 UT WOS:000073239600008 ER PT J AU Nunes, RW Bennetto, J Vanderbilt, D AF Nunes, RW Bennetto, J Vanderbilt, D TI Atomic structure of dislocation kinks in silicon SO PHYSICAL REVIEW B LA English DT Article ID 90-DEGREES PARTIAL DISLOCATION; TOTAL-ENERGY CALCULATIONS; MOTION; MOBILITY; SI; SEMICONDUCTORS; MIGRATION; CRYSTALS; BARRIERS; SYSTEM AB We investigate the physics of the core reconstruction and associated structural excitations (reconstruction defects and kinks) of dislocations in silicon, using a Linear-scaling density-matrix technique. The two predominant dislocations (the 90 degrees and 30 degrees partials) are examined, focusing for the 90 degrees case on the single-period core reconstruction. In both cases, we observe strongly reconstructed bonds at the dislocation cores, as suggested in previous studies. As a consequence, relatively low formation energies and high migration barriers are generally associated with reconstructed (dangling-bond-free) kinks. Complexes formed of a kink plus a reconstruction defect are found to be strongly bound in the 30 degrees partial, while the opposite is true in the case of 90 degrees partial, where such complexes are found to be only marginally stable at zero temperature with very low dissociation barriers. For the 300 partial, our calculated formation energies and migration barriers of kinks are seen to compare favorably with experiment. Our results for the kink energies on the 90 degrees partial an consistent with a recently proposed alternative double-period structure for the core of this dislocation. [S0163-1829(98)10617-3]. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. George Mason Univ, Fairfax, VA 22030 USA. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08855 USA. RP Nunes, RW (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RI Nunes, Ricardo Wagner/M-9974-2014; OI Nunes, Ricardo Wagner/0000-0003-2810-8649; Vanderbilt, David/0000-0002-2465-9091 NR 37 TC 56 Z9 58 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 MAY 1 PY 1998 VL 57 IS 17 BP 10388 EP 10397 DI 10.1103/PhysRevB.57.10388 PG 10 WC Physics, Condensed Matter SC Physics GA ZL728 UT WOS:000073464500040 ER PT J AU Pickett, WE AF Pickett, WE TI Spin-density-functional-based search for half-metallic antiferromagnets SO PHYSICAL REVIEW B LA English DT Article ID GROUND-STATE PROPERTIES; ELECTRONIC-STRUCTURE; SUPERCONDUCTIVITY AB We present results based on local-spin-density calculations of a computational search for half-metallic (HM) antiferromagnetic (Arm) materials within the class of double-perovskite-structure oxides LaM'M"O-3 that incorporate open-shell 3d (or 4d) transition-metal ions M',M". The pairs M'M"=MnCo, CrFe, CrRu, CrNi, MnV, and VCu are studied. Three HM AFM results are found for the (fixed) cubic double perovskite structure. This work provides the first viable candidates for this unusual magnetic phase. La2VMnO6 is the most promising candidate, with the HM AFM phase more stable by 0.17 eV/cell than the ferromagnetic phase. La2VCuO6 is another promising possibility but, because V4+ and Cu2+ are spin-half ions, quantum fluctuations may play an important role in determining the ground state magnetic and electronic structure. This study indicates that HM AFM materials should not be prohibitively difficult to find. [S0163-1829(98)07517-1]. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Pickett, WE (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM pickett@physics.ucdavis.edu NR 22 TC 151 Z9 154 U1 3 U2 16 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 MAY 1 PY 1998 VL 57 IS 17 BP 10613 EP 10619 DI 10.1103/PhysRevB.57.10613 PG 7 WC Physics, Condensed Matter SC Physics GA ZL728 UT WOS:000073464500070 ER PT J AU Bill, A Kresin, VZ Wolf, SA AF Bill, A Kresin, VZ Wolf, SA TI Isotope effect for the penetration depth in superconductors SO PHYSICAL REVIEW B LA English DT Article ID NORMAL-STATE; TRANSITION-TEMPERATURE; EFFECTIVE-MASS; PAIR BREAKING; APEX-OXYGEN; LA2-XSRXCUO4; YBA2CU3O7; CARRIERS AB We show that various factors can lead to an isotopic dependence of the penetration depth delta. Nonadiabaticity (Jahn-Teller crossing) leads to the isotope effect of the charge-carrier concentration n and, consequently, of delta in doped superconductors such as the cuprates. A general equation relating the isotope coefficients of T-c and of delta is presented for London superconductors. We further show that the presence of magnetic impurities or a proximity contact also lead to an isotopic dependence of delta; the isotope coefficient turns out to be temperature dependent, beta(T), in these cases. The existence of the isotope effect for the penetration depth is predicted for conventional as well as for high-temperature superconductors. Various experiments are proposed and/or discussed. [S0163-1829(98)03617-0]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. USN, Res Lab, Washington, DC 20375 USA. RP Bill, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Wolf, Stuart/A-7513-2009 NR 53 TC 19 Z9 19 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 MAY 1 PY 1998 VL 57 IS 17 BP 10814 EP 10824 DI 10.1103/PhysRevB.57.10814 PG 11 WC Physics, Condensed Matter SC Physics GA ZL728 UT WOS:000073464500096 ER PT J AU Rajagopal, AK Mochena, M AF Rajagopal, AK Mochena, M TI Spin-orbit interactions in the many-body theory of magnetic electron systems SO PHYSICAL REVIEW B LA English DT Article AB We have developed here a many-body theory of magnetic electron systems including both the one-and two-particle spin-orbit interactions. Among the two-particle spin-orbit interactions, we focus attention on the spin-same orbit and spin-other orbit terms, which were considered recently in the literature for nonmagnetic systems. The spinor-Green function method employed here provides a clear self-consistent way of treating both the single-particle and the two-particle properties in the system. It enables us to express in an elegant fashion screening effects that appear in different forms with transparent physical significance to each type. We carry out in some detail these contributions in the random-phase approximation and paint out their significance especially in the magnetic systems. This development is a contribution towards a new understanding of magnetism in a wide class of systems ranging from clusters to nanomagnets that possess very large spin moments. This should also be of importance in the new studies of spin transport and magnetoelectronics, specifically in magnetic systems in low dimensions. C1 USN, Res Lab, Washington, DC 20375 USA. Florida A&M Univ, Dept Phys, Tallahassee, FL 32307 USA. RP USN, Res Lab, Washington, DC 20375 USA. NR 16 TC 6 Z9 6 U1 0 U2 4 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 MAY 1 PY 1998 VL 57 IS 18 BP 11582 EP 11591 DI 10.1103/PhysRevB.57.11582 PG 10 WC Physics, Condensed Matter SC Physics GA ZM876 UT WOS:000073585200073 ER PT J AU Hicks, SF Davoren, CM Faulkner, WM Vanhoy, JR AF Hicks, SF Davoren, CM Faulkner, WM Vanhoy, JR TI Structural characteristics of Nd-144 through gamma-ray spectroscopy following inelastic neutron scattering SO PHYSICAL REVIEW C LA English DT Article ID INTERACTING-BOSON MODEL; MIXED-SYMMETRY STATES; LOW-LYING STATES; OCTUPOLE EXCITATIONS; NUCLEAR-STRUCTURE; CE-142; TRANSITIONS; ISOTOPES; BA-140; SM-146 AB Excited levels in Nd-144 below 3.3 MeV have been studied using the (n,n' gamma) reaction. Electromagnetic transition probabilities, multipole-mixing and branching ratios, and level spins and parities were deduced from measured gamma-ray excitation functions, angular distributions, and Doppler shifts. Mixed-symmetry configurations in low-lying excited states were investigated by comparing experimental electromagnetic transition rates with theoretical calculations made using the interacting boson model and with existing calculations from the quasiparticle phonon model, the cluster vibrator model, and the particle-core coupling model. Fragmentation of the 2(+) mixed-symmetry mode is clearly observed through strong M1 transitions into the lowest symmetric 2(+) level and through small E2/M1 multipole-mixing ratios. Comparisons with similar measurements on Ce-142 reveal that these N=84 isotones exhibit strong fragmentation of the mixed-symmetry mode, although it appears to be spread into more levels in Nd-144. Evidence is found to support the assignment of the 2779.0-keV level as the 3(-) member of the octupole-quadrupole phonon coupled quintuplet in Nd-144 and to propose that this excited mode is shared with the 2606.0-keV state. Two- and three-quadrupole phonon excitations, as well as other members of the quadrupole-octupole quintuplet, are also examined. [S0556-2813(98)06105-6]. C1 Univ Dallas, Dept Phys, Irving, TX 75062 USA. USN Acad, Dept Phys, Annapolis, MD 21402 USA. RP Hicks, SF (reprint author), Univ Dallas, Dept Phys, Irving, TX 75062 USA. NR 43 TC 26 Z9 26 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1998 VL 57 IS 5 BP 2264 EP 2280 DI 10.1103/PhysRevC.57.2264 PG 17 WC Physics, Nuclear SC Physics GA ZP516 UT WOS:000073761300024 ER PT J AU Saylor, JR Sreenivasan, KR AF Saylor, JR Sreenivasan, KR TI Differential diffusion in low Reynolds number water jets SO PHYSICS OF FLUIDS LA English DT Article ID PHASE TURBULENT JETS; MOLECULAR-DIFFUSION; PASSIVE SCALARS; FLAMES; TRANSPORT AB Experimental data on differential diffusion between two species with large and quite disparate Schmidt numbers were obtained in a turbulent water jet by optically measuring the two species concentrations simultaneously. Experimental conditions were chosen so that the species were dilute and did not affect the water density thereby avoiding inertial effects. Differential diffusion was found to be significant in magnitude, even in the absence of these effects. Schmidt number ratios of 4 and 18 were considered. Differential diffusion was found to be statistically significant and to manifest at scales larger than the computed Batchelor scale. In some instances the concentration signal for the species with larger diffusivity was simply a blurred version of the other. while in other instances structures present in one signal were completely absent from the other. This second observation, presumably a more complex effect due to diffusion across velocity gradients, is discussed. (C) 1998 American Institute of Physics. C1 Yale Univ, Mason Lab, New Haven, CT 06511 USA. RP Saylor, JR (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 24 TC 27 Z9 27 U1 0 U2 4 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 MAY PY 1998 VL 10 IS 5 BP 1135 EP 1146 DI 10.1063/1.869638 PG 12 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA ZJ970 UT WOS:000073272000010 ER PT J AU Velikovich, AL Dahlburg, JP Gardner, JH Taylor, RJ AF Velikovich, AL Dahlburg, JP Gardner, JH Taylor, RJ TI Saturation of perturbation growth in ablatively driven planar laser targets SO PHYSICS OF PLASMAS LA English DT Article ID RAYLEIGH-TAYLOR INSTABILITY; BEAM; IMPRINT; PLASMA; FOILS; MATTER; FUSION AB Saturation of the mass variation growth during the shock transit time, theoretically predicted for the surface roughness case by Ishizaki and Nishihara [Phys. Rev. Lett. 78, 1920 (1997)] and for the laser imprint case by Taylor et al. [Phys. Rev. Lett. 79, 1861 (1997)], is studied analytically and numerically. The saturation is demonstrated to be essentially the same effect in both cases, caused by the stabilizing action of mass ablation. Scalings of saturation time and saturation level for the two cases are related. For lower-density foam targets, the peak level of mass variation is proportional approximately to rho(0)(1/2) and exactly to rho(0) for the cases of laser imprint and surface roughness, respectively. (C) 1998 American Institute of Physics. C1 Berkeley Res Associates Inc, Springfield, VA 22150 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. USN, Res Lab, LCP&FD, Washington, DC 20375 USA. Univ London Imperial Coll Sci Technol & Med, London SW7 2BZ, England. RP Berkeley Res Associates Inc, Springfield, VA 22150 USA. RI Velikovich, Alexander/B-1113-2009 NR 37 TC 46 Z9 47 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1998 VL 5 IS 5 BP 1491 EP 1505 DI 10.1063/1.872808 PN 1 PG 15 WC Physics, Fluids & Plasmas SC Physics GA ZM871 UT WOS:000073584700030 ER PT J AU Leemans, WP Volfbeyn, P Guo, KZ Chattopadhyay, S Schroeder, CB Shadwick, BA Lee, PB Wurtele, JS Esarey, E AF Leemans, WP Volfbeyn, P Guo, KZ Chattopadhyay, S Schroeder, CB Shadwick, BA Lee, PB Wurtele, JS Esarey, E TI Laser-driven plasma-based accelerators: Wakefield excitation, channel guiding, and laser triggered particle injection SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 39th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 17-21, 1997 CL PITTSBURGH, PENNSYLVANIA SP Amer Phys Soc, Div Plasma Phys ID COLD INHOMOGENEOUS PLASMA; WAKE-FIELD ACCELERATION; UNDERDENSE PLASMAS; ELECTROSTATIC OSCILLATIONS; EQUATION APPROACH; SELF-MODULATION; PULSE; INTENSE; WAVES; PROPAGATION AB Plasma-based accelerators are discussed in which high-power short pulse lasers are the power source, suitably tailored plasma structures provide guiding of the laser beam and support large accelerating gradients, and an optical scheme is used to produce time-synchronized ultrashort electron bunches. From scaling laws laser requirements are obtained for development of compact high-energy accelerators. Simulation results of laser guiding and wakefield excitation in plasma channels, as well as laser-based injection of particles into a plasma wake, are presented. Details of the experimental program at Lawrence Berkeley National Laboratory on laser guiding, laser wakefield-based accelerators, and laser triggered injection are given. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. USN, Res Lab, Washington, DC 20375 USA. RP Leemans, WP (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. EM leemans@lbl.gov RI wurtele, Jonathan/J-6278-2016; OI wurtele, Jonathan/0000-0001-8401-0297; Schroeder, Carl/0000-0002-9610-0166 NR 58 TC 57 Z9 57 U1 3 U2 15 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 MAY PY 1998 VL 5 IS 5 SI SI BP 1615 EP 1623 DI 10.1063/1.872820 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA ZN238 UT WOS:000073623700006 ER PT J AU Bodner, SE Colombant, DG Gardner, JH Lehmberg, RH Obenschain, SP Phillips, L Schmitt, AJ Sethian, JD McCrory, RL Seka, W Verdon, CP Knauer, JP Afeyan, BB Powell, HT AF Bodner, SE Colombant, DG Gardner, JH Lehmberg, RH Obenschain, SP Phillips, L Schmitt, AJ Sethian, JD McCrory, RL Seka, W Verdon, CP Knauer, JP Afeyan, BB Powell, HT TI Direct-drive laser fusion: Status and prospects SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 39th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 17-21, 1997 CL PITTSBURGH, PENNSYLVANIA SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; INDUCED SPATIAL INCOHERENCE; STEEP TEMPERATURE-GRADIENTS; CONSISTENT STABILITY ANALYSIS; INERTIAL CONFINEMENT FUSION; STIMULATED RAMAN-SCATTERING; SCALE-LENGTH PLASMAS; HYDRODYNAMIC INSTABILITIES; INHOMOGENEOUS PLASMAS; UNIFORM ILLUMINATION AB Techniques have been developed to improve the uniformity of the laser focal profile, to reduce the ablative Rayleigh-Taylor instability, and to suppress the various laser-plasma instabilities. There are now three direct-drive ignition target designs that utilize these techniques. An evaluation of these designs is still ongoing. Some of them may achieve the gains above 100 that are necessary for a fusion reactor. Two laser systems have been proposed that may meet all of the requirements for a fusion reactor. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. Polymath Associates, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. RP Bodner, SE (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 111 TC 248 Z9 256 U1 9 U2 31 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 MAY PY 1998 VL 5 IS 5 SI SI BP 1901 EP 1918 DI 10.1063/1.872861 PN 2 PG 18 WC Physics, Fluids & Plasmas SC Physics GA ZN238 UT WOS:000073623700042 ER PT J AU Klapisch, M Bar-Shalom, A Oreg, J Colombant, D AF Klapisch, M Bar-Shalom, A Oreg, J Colombant, D TI Non local-thermodynamical-equilibrium effects in the simulation of laser-produced plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 39th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 17-21, 1997 CL PITTSBURGH, PENNSYLVANIA SP Amer Phys Soc, Div Plasma Phys ID X-RAY SPECTROSCOPY; IONIZATION BALANCE; TRANSITION-ARRAYS; SPECTRA; MODEL; RADIATION; TEMPERATURE; TARGETS; DRIVE; ATOMS AB Local thermodynamic equilibrium (LTE) breaks down in directly or indirectly driven laser plasmas because of sharp gradients,energy deposition, etc. For modeling non-LTE effects in hydrodynamical simulations, Busquet's model [Phys. Fluids B 5, 4191 (1993)] is very convenient and efficient. It uses off-line generated LTE opacities and equation of states via an effective, radiation-dependent ionization temperature T-z. An overview of the model is given. The results are compared with an elaborate collisional radiative model based on superconfigurations. The agreements for average charge Z* and opacities are surprisingly good, even more so when the plasma is immersed in a radiation field. Some remaining discrepancy at low density is attributed to dielectronic recombination. Improvement appears possible, especially for emissivities, because the concept of ionization temperature seems to be validated. (C) 1998 American Institute of Physics. C1 ARTEP Inc, Columbia, MD 20145 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NRCN, Beer Sheva, Israel. RP Klapisch, M (reprint author), ARTEP Inc, Columbia, MD 20145 USA. EM klapisch@this.nrl.navy.mil NR 42 TC 24 Z9 29 U1 0 U2 1 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 MAY PY 1998 VL 5 IS 5 SI SI BP 1919 EP 1926 DI 10.1063/1.872862 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA ZN238 UT WOS:000073623700043 ER PT J AU Gardner, JH Schmitt, AJ Dahlburg, JP Pawley, CJ Bodner, SE Obenschain, SP Serlin, V Aglitskiy, Y AF Gardner, JH Schmitt, AJ Dahlburg, JP Pawley, CJ Bodner, SE Obenschain, SP Serlin, V Aglitskiy, Y TI Computational modeling of direct-drive fusion pellets and KrF-driven foil experiments SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 39th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 17-21, 1997 CL PITTSBURGH, PA SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; INDUCED SPATIAL INCOHERENCE; LASER-CREATED PLASMAS; IONIZATION MODEL; TARGETS; RADIATION; ABLATION; IMPRINT; GROWTH; BEAM AB FAST is a radiation transport hydrodynamics code that simulates laser matter interactions of relevance to direct-drive laser fusion target design. FAST solves the Euler equations of compressible dow using the Flux-Corrected Transport finite volume method. The advection algorithm provides accurate computation of flows from nearly incompressible vortical flows to those that are highly compressible and dominated by strong pressure and density gradients. In this paper we describe the numerical techniques and physics packages. FAST has also been benchmarked with Nike laser facility experiments in which linearly perturbed, low adiabat planar plastic targets are ablatively accelerated to velocities approaching 10(7) cm/s. Over a range of perturbation wavelengths, the code results agree with the measured Rayleigh-Taylor growth from the linear through the deeply nonlinear regimes. FAST has been applied to the two-dimensional spherical simulation design to provide surface finish and laser bandwidth tolerances for a promising new direct-drive pellet that uses a foam ablator. C1 USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Sci Applicat Int Inc, Mclean, VA 22310 USA. RP USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. NR 41 TC 48 Z9 48 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1998 VL 5 IS 5 SI SI BP 1935 EP 1944 DI 10.1063/1.872863 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA ZN238 UT WOS:000073623700045 ER PT J AU Bernhardt, PA McCoy, RP Dymond, KF Picone, JM Meier, RR Kamalabadi, F Cotton, DM Charkrabarti, S Cook, TA Vickers, JS Stephan, AW Kersley, L Pryse, SE Walker, IK Mitchell, CN Straus, PR Na, H Biswas, C Bust, GS Kronschnabl, GR Raymund, TD AF Bernhardt, PA McCoy, RP Dymond, KF Picone, JM Meier, RR Kamalabadi, F Cotton, DM Charkrabarti, S Cook, TA Vickers, JS Stephan, AW Kersley, L Pryse, SE Walker, IK Mitchell, CN Straus, PR Na, H Biswas, C Bust, GS Kronschnabl, GR Raymund, TD TI Two-dimensional mapping of the plasma density in the upper atmosphere with computerized ionospheric tomography (CIT) SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 39th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 17-21, 1997 CL PITTSBURGH, PENNSYLVANIA SP Amer Phys Soc, Div Plasma Phys ID MODEL; SPECTROSCOPY; DAYGLOW AB Tomographic imaging of the ionosphere is a recently developed technique that uses integrated measurements and computer reconstructions to determine electron densities. The integral of electron density along vertical or oblique paths is obtained with radio transmissions from low-earth-orbiting (LEO) satellite transmitters to a chain of receivers on the earth's surface. Similar measurements along horizontal paths can be made using transmissions from Global Position System (GPS) navigation satellites to GPS receivers on LEO spacecraft. Also, the intensities of extreme ultraviolet (EUV) emissions can be measured with orbiting spectrometers, These intensities are directly related to the integral of the oxygen ion and electron densities along the instrument line of sight, Two-dimensional maps of the ionospheric plasma are produced by analyzing the combined radio and EUV data using computerized ionospheric tomography (CIT), Difficulties associated with CIT arise from the nonuniqueness of the reconstructions, owing to limited angle measurements or nonoptimal receiver location. Improvements in both reconstruction algorithms and CIT measurement systems are being implemented to overcome these difficulties. New imaging systems being developed employ CIT for large area mapping of the plasma densities in the ionosphere, (C) 1998 American Institute of Physics. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Off Naval Res, Arlington, VA 22217 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Boston Univ, Space Res Ctr, Boston, MA 02215 USA. Univ Coll Wales, Dept Phys, Aberystwyth SY23 3BZ, Dyfed, Wales. Aerospace Corp, Los Angeles, CA 90009 USA. Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. Univ Texas, Appl Res Labs, Austin, TX 78718 USA. RP Bernhardt, PA (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RI Meier, Robert/G-4749-2014; OI Meier, Robert/0000-0001-8497-7115; Dymond, Kenneth/0000-0001-8060-9016 NR 39 TC 49 Z9 49 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1998 VL 5 IS 5 SI SI BP 2010 EP 2021 DI 10.1063/1.872872 PN 2 PG 12 WC Physics, Fluids & Plasmas SC Physics GA ZN238 UT WOS:000073623700054 ER PT J AU Fernsler, RF Manheimer, WM Meger, RA Mathew, J Murphy, DP Pechacek, RE Gregor, JA AF Fernsler, RF Manheimer, WM Meger, RA Mathew, J Murphy, DP Pechacek, RE Gregor, JA TI Production of large-area plasmas by electron beams SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 39th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 17-21, 1997 CL PITTSBURGH, PENNSYLVANIA SP Amer Phys Soc, Div Plasma Phys ID MIRROR AB An analysis is presented for the production of weakly ionized plasmas by electron beams, with an emphasis on the production of broad, planar plasmas capable of reflecting X-band microwaves. Considered first in the analysis is the ability of weakly ionized plasmas to absorb, emit and reflect electromagnetic radiation. Following that is a determination of the electron beam parameters needed to produce plasmas, based on considerations of beam ionization, range, and stability. The results of the analysis are then compared with a series of experiments performed using a sheet electron beam to produce plasmas up to 0.6 m square by 2 cm thick. The electron beam in the experiments was generated using a long hollow-cathode discharge operating in an enhanced-glow mode. That mode has only recently been recognized, and a brief analysis of it is given for completeness. The conclusion of the study is that electron beams can produce large-area, planar plasmas with high efficiency, minimal gas heating, low electron temperature, high uniformity, and high microwave reflectivity, as compared with plasmas produced by other sources. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Beam Phys Branch, Washington, DC 20375 USA. RP Fernsler, RF (reprint author), USN, Res Lab, Beam Phys Branch, Code 6750,4555 Overlook Ave SW, Washington, DC 20375 USA. EM fern@ppd.nrl.navy.mil NR 20 TC 58 Z9 64 U1 0 U2 4 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 MAY PY 1998 VL 5 IS 5 SI SI BP 2137 EP 2143 DI 10.1063/1.872886 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA ZN238 UT WOS:000073623700069 ER PT J AU Renk, TJ Buchheit, RG Sorensen, NR Senft, DC Thompson, MO Grabowski, KS AF Renk, TJ Buchheit, RG Sorensen, NR Senft, DC Thompson, MO Grabowski, KS TI Improvement of surface properties by modification and alloying with high-power ion beams SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 39th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 17-21, 1997 CL PITTSBURGH, PENNSYLVANIA SP Amer Phys Soc, Div Plasma Phys AB Surface treatment and alloying experiments with Al, Fe, and Ti-based metals as well as Si wafers were conducted on the Repetitive High Energy Pulsed Power-I (RHEPP-I) accelerator [0.8 MV, 20 Ohm, 80 ns full width at half maximum (FWHM) pulse width, up to 1 Hz repetition rate] at Sandia National Laboratories. Ions are generated by the magnetically confined anode plasma (MAP) gas-breakdown active anode, which can yield a number of different beam species including H, C, N, O, Kr, and Xe, depending upon the injected gas. Enhanced hardness and wear resistance have been produced by treatment of 440C stainless steel, by the mixing of a thin-film Pt coating into Ti-6Al-4V alloy, and of a Si coating into Al 6061-T6 alloy (Al-1.0Mg-0.6Si). Mixing of a thin-film Hf layer into Al 6061-T6 has improved its corrosion resistance by as much as four orders of magnitude in electrochemical testing, compared with untreated and uncoated Al6061. Processing of Si was used to validate simulation codes. When treated with nitrogen ions, melt and full epitaxial growth was observed to depths of 4-6 mu m. Experiments are ongoing to further understand the microstructural basis for these surface improvements. (C) 1998 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Cornell Univ, Dept Mat Sci, Ithaca, NY 14853 USA. USN, Res Lab, Washington, DC 20375 USA. RP Renk, TJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. OI Grabowski, Kenneth/0000-0003-0816-001X; Thompson, Michael/0000-0002-4933-009X NR 8 TC 24 Z9 26 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 MAY PY 1998 VL 5 IS 5 SI SI BP 2144 EP 2150 DI 10.1063/1.872887 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA ZN238 UT WOS:000073623700070 ER PT J AU Gardner, MJ Tettelin, H Carucci, DJ Cummings, LM Adams, MD Smith, HO Venter, JC Hoffman, SL AF Gardner, MJ Tettelin, H Carucci, DJ Cummings, LM Adams, MD Smith, HO Venter, JC Hoffman, SL TI The malaria genome sequencing project SO PROTIST LA English DT Article C1 Inst Genom Res, Rockville, MD 20850 USA. USN, Med Res Inst, Malaria Program, Rockville, MD 20852 USA. RP Gardner, MJ (reprint author), Inst Genom Res, 9712 Med Ctr Dr, Rockville, MD 20850 USA. NR 8 TC 5 Z9 5 U1 0 U2 1 PU GUSTAV FISCHER VERLAG PI JENA PA VILLENGANG 2, D-07745 JENA, GERMANY SN 1434-4610 J9 PROTIST JI Protist PD MAY PY 1998 VL 149 IS 2 BP 109 EP 112 PG 4 WC Microbiology SC Microbiology GA 103CC UT WOS:000074962800002 PM 23196159 ER PT J AU Dessler, AE Burrage, MD Grooss, JU Holton, JR Lean, JL Massie, ST Schoeberl, MR Douglass, AR Jackman, CH AF Dessler, AE Burrage, MD Grooss, JU Holton, JR Lean, JL Massie, ST Schoeberl, MR Douglass, AR Jackman, CH TI Selected science highlights from the first 5 years of the Upper Atmosphere Research Satellite (UARS) program SO REVIEWS OF GEOPHYSICS LA English DT Review ID RESOLUTION DOPPLER IMAGER; IRRADIANCE COMPARISON EXPERIMENT-1; HALOGEN OCCULTATION EXPERIMENT; VIBRATIONALLY EXCITED OXYGEN; ARRAY ETALON SPECTROMETER; POLAR VORTEX CONDITIONS; ARCTIC OZONE DEPLETION; SOLAR TOTAL IRRADIANCE; LONG-TERM VARIABILITY; ZONAL MEAN WINDS AB We present scientific highlights from the Upper Atmosphere Research Satellite (UARS) program obtained during the first 5 years of the program. The UARS measures the chemical composition and meteorological state of the middle and upper atmosphere as well as the solar irradiance. The comprehensive suite of UARS geophysical parameters, their near-global coverage, and the multiyear time span have yielded new insights into the processes affecting our atmosphere. In this article we select: seven scientific issues, including stratospheric ozone chemistry, the dynamics of the middle and upper atmosphere, and solar irradiance variations, and discuss the significant impact that the UARS observations have had on our understanding of each issue. C1 Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Space Phys Res Lab, Ann Arbor, MI 48109 USA. Forschungszentrum Julich, ICG1, D-52425 Julich, Germany. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. USN, Res Lab, Washington, DC 20375 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Dessler, AE (reprint author), Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. EM dessler@atmos.umd.edu; burrage@sprlj.sprl.umich.edu; j.-u.grooss@fz-juelich.de; holton@atmos.washington.edu; lean@demeter.nrl.navy.mil; massie@ncar.ucar.edu; schom@zephyr.gsfc.nasa.gov; douglass@xena.gsfc.nasa.gov; jackman@welkin.span.nasa.gov RI Douglass, Anne/D-4655-2012; GrooSS, Jens-Uwe/A-7315-2013; Jackman, Charles/D-4699-2012; Dessler, Andrew/G-8852-2012; OI GrooSS, Jens-Uwe/0000-0002-9485-866X; Dessler, Andrew/0000-0003-3939-4820; Lean, Judith/0000-0002-0087-9639 NR 137 TC 28 Z9 28 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 8755-1209 J9 REV GEOPHYS JI Rev. Geophys. PD MAY PY 1998 VL 36 IS 2 BP 183 EP 210 DI 10.1029/97RG03549 PG 28 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 126CW UT WOS:000076276200002 ER PT J AU Voros, SD AF Voros, SD TI Dramas of distinction: Plays by Golden Age women SO REVISTA DE ESTUDIOS HISPANICOS LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Voros, SD (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU REVISTA DE ESTUDIOS HISPANICOS PI ST LOUIS PA WASHINGTON UNIV, BOX 1077, DEPT ROMANCE LANG, ONE BROOKINGS DR, ST LOUIS, MO 63130-4899 USA SN 0034-818X J9 REV ESTUD HISPAN JI Rev. Estud. Hisp. PD MAY PY 1998 VL 32 IS 2 BP 452 EP 453 PG 2 WC Literature, Romance SC Literature GA ZQ054 UT WOS:000073816800035 ER PT J AU Nagel, DJ AF Nagel, DJ TI Materials and processes for microsystems SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 10th International Conference on Surface Modification of Metals by Ion Beams (SMMIB 97) CY SEP 21-26, 1997 CL GATLINBURG, TN SP Oak Ridge Natl Lab, Danfysik, Implant Sci Corp, Spire Corp DE ion beams; ion implantation; MEMS; microsystems AB Microsystems, often called microelectromechanical systems (MEMS), are essentially chips with moving parts. Commercial production of MEMS is predicted to cross the $10B per year mark around the year 2000. Materials, and the processes required to deposit, modify and pattern them, pace the development, production and performance of microsystems. Three eras in the employment of materials and processes for MEMS manufacture are defined and discussed. The development and use of emerging materials will lead to improved MEMS. Exploitation of available and new processes, such as ion beam technologies, is a promising avenue for research. Whether or not future advances in MEMS performance and applications will be comparable to the past growth of integrated circuits remains to be determined. However, it is highly likely that MEMS will have a widespread and major impact on both large systems and consumer goods. Published by Elsevier Science S.A. C1 USN, Res Lab, Washington, DC 20375 USA. RP Nagel, DJ (reprint author), USN, Res Lab, Code 6600,4555 Overlook Ave SW, Washington, DC 20375 USA. EM nagel@dave.nrl.navy.mil NR 11 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD MAY PY 1998 VL 104 BP 138 EP 145 PG 8 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA ZZ476 UT WOS:000074733200027 ER PT J AU Wahl, KJ Stepnowski, SV Unertl, WN AF Wahl, KJ Stepnowski, SV Unertl, WN TI Viscoelastic effects in nanometer-scale contacts under shear SO TRIBOLOGY LETTERS LA English DT Article DE nanotribology; viscoelastic contacts; shear modulation; scanned force microscope single-asperity contacts; poly(vinylethylene) ID ATOMIC-FORCE-MICROSCOPE; CONFINED POLYMER MELTS; LATERAL STIFFNESS; FRICTION; ADHESION; POLY(VINYLETHYLENE); CALIBRATION; RHEOLOGY; SURFACES; FILM AB We demonstrate the effects of shear modulation on the viscoelastic response of nanometer-scale single-asperity contacts under static and dynamic loading conditions. Contact stiffness and relaxation time are determined for contacts to poly(vinylethylene) using a scanning force microscope (SFM). Knowledge of the torsional stiffness kappa(Theta) of the SFM cantilever is not required to determine the relaxation time. The relaxation time was several orders of magnitude slower than the bulk relaxation time but decreased slowly to the bulk value as the sample age increased. Contacts showed no evidence of microslip. We show that the shear response observed during the making and breaking of the contacts provides information about the time evolution of the contact area that is not available in force vs, distance curve measurements. C1 USN, Res Lab, Washington, DC 20375 USA. RP Wahl, KJ (reprint author), USN, Res Lab, Code 6170, Washington, DC 20375 USA. OI Wahl, Kathryn/0000-0001-8163-6964 NR 33 TC 60 Z9 60 U1 1 U2 13 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1023-8883 J9 TRIBOL LETT JI Tribol. Lett. PD MAY PY 1998 VL 5 IS 1 BP 103 EP 107 DI 10.1023/A:1019169019617 PG 5 WC Engineering, Chemical; Engineering, Mechanical SC Engineering GA 115WJ UT WOS:000075689100012 ER PT J AU Merguerian, PA Mevorach, RA Shortliffe, LDS Cendron, M AF Merguerian, PA Mevorach, RA Shortliffe, LDS Cendron, M TI Laparoscopy for the evaluation and management of the nonpalpable testicle SO UROLOGY LA English DT Article ID FOWLER-STEPHENS; INTRAABDOMINAL TESTES; IMPALPABLE TESTES; ORCHIOPEXY; EXPERIENCE; VESSELS; CRYPTORCHIDISM; DIAGNOSIS; LIGATION; UROLOGY AB Objective: To assess the usefulness of laparoscopy for the diagnosis and treatment of the nonpalpable testicle and to evaluate the results of laparoscopic orchidopexy. Methods: We retrospectively reviewed the charts of 91 laparoscopies performed over a period of 4 years. We reviewed the following parameters: findings, complications, patency of the processus vaginalis, appearance of the cord structures, and the success of the different procedures performed for the intra-abdominal testicle. Results: Fourteen patients had bilateral and 77 unilateral nonpalpable testicles. The mean age of the patients was 39.5 +/- 50.8 months. There were three laparoscopic complications (3.2%) one of which was a major bowel laceration. Laparoscopy defined the intra-abdominal anatomy accurately in 90 of the 91 cases Of the 26 intra-abdominal testicles above the ring, a one-stage laparoscopic orchidopexy was performed in five and a single-stage standard orchidopexy in seven. All of these testicles remain viable and are in good position. Eight patients underwent a staged Fowler-Stephens orchidopexy with laparoscopic clipping of the spermatic vessels as the first stage. Of these, a second-stage open orchidopexy was performed in five and a laparoscopic orchidopexy in three. Testicular atrophy occurred in two of the patients who underwent the second-stage open orchidopexy. Three one-stage Fowler-Stephens orchidopexies were performed with testicular atrophy occurring in two of these testicles. Laparoscopic orchiectomy was performed on two patients. Conclusions: Laparoscopy is a valuable tool in the diagnosis and treatment of the nonpalpable testicle. Laparoscopic orchidopexy may decrease the rate of testicular atrophy since most of these can be performed laparoscopically in one stage, thus preserving the Vascular supply. (C) 1998, Elsevier Science Inc. All rights reserved. C1 Hosp Sick Children, Div Urol, Toronto, ON M5G 1X8, Canada. USN, Med Ctr, Dept Urol, San Diego, CA 92152 USA. Stanford Univ, Med Ctr, Dept Urol, Stanford, CA 94305 USA. Dartmouth Hitchcock Med Ctr, Urol Sect, Lebanon, NH 03766 USA. RP Merguerian, PA (reprint author), Hosp Sick Children, Div Urol, 555 Univ Ave, Toronto, ON M5G 1X8, Canada. NR 30 TC 28 Z9 28 U1 0 U2 0 PU CAHNERS PUBL CO PI NEW YORK PA 249 WEST 17 STREET, NEW YORK, NY 10011 USA SN 0090-4295 J9 UROLOGY JI UROLOGY PD MAY PY 1998 VL 51 SU 5A BP 3 EP 6 DI 10.1016/S0090-4295(98)00083-1 PG 4 WC Urology & Nephrology SC Urology & Nephrology GA ZQ448 UT WOS:000073863100003 PM 9610548 ER PT J AU Mevorach, RA Merguerian, PA Balcolm, AH AF Mevorach, RA Merguerian, PA Balcolm, AH TI Detrusorrhaphy for repair of unilateral vesicoureteral reflux: Report of 76 patients using a modified technique SO UROLOGY LA English DT Article ID URETERAL REIMPLANTATION; CONTRALATERAL REFLUX; URETERONEOCYSTOSTOMY; MANAGEMENT AB Objective. To present our results for repair of unilateral vesicoureteral reflux in 76 children using a modified technique of detrusorrhaphy. Methods. A retrospective chart review was performed for 76 children who underwent repair of unilateral vesicoureteral reflux by a modified technique of detrusorrhaphy. Of the 76 refluxing ureters, 12 were associated with historically refluxing contralateral ureters. In addition, 72/76 were grades II to IV; 4/76 grade V; three had a paraureteral diverticulum; four completely duplicated collecting systems; and two had associated ureteroceles. The surgical technique was modified to preserve both the obliterated umbilical artery and superior vesical pedicle and to minimize trigonal distortion through dissection lateral to the trigone in a direct path to the bladder neck. Results. Seventy-five of 76 ureters were successfully repaired (99%). The remaining ureter showed initial improvement to grade I reflux and spontaneous resolution by I year. Obstruction did not occur. Three episodes of "new onset" contralateral vesicoureteral reflux were noted postoperatively. This represents a substantial decrease in incidence (3.9%) when compared with previously reported series (18%). Conclusion. Detrusorrhaphy is a reasonable treatment of unilateral vesicoureteral reflux with utility in the full range of anatomic associations. This approach is also associated with a lower incidence of new onset, contralateral reflux when compared with intravesical surgery. (C) 1998, Elsevier Science Inc. All rights reserved. C1 USN, Med Ctr, Dept Urol, San Diego, CA 92134 USA. Stanford Univ, Med Ctr, Dept Urol, Stanford, CA 94305 USA. Childrens Hosp Wisconsin, Milwaukee, WI 53201 USA. Med Coll Wisconsin, Milwaukee, WI 53226 USA. RP Mevorach, RA (reprint author), USN, Med Ctr, Dept Urol, San Diego, CA 92134 USA. NR 15 TC 1 Z9 1 U1 0 U2 1 PU CAHNERS PUBL CO PI NEW YORK PA 249 WEST 17 STREET, NEW YORK, NY 10011 USA SN 0090-4295 J9 UROLOGY JI UROLOGY PD MAY PY 1998 VL 51 SU 5A BP 12 EP 14 DI 10.1016/S0090-4295(98)00072-7 PG 3 WC Urology & Nephrology SC Urology & Nephrology GA ZQ448 UT WOS:000073863100005 PM 9610550 ER PT J AU Tasker, SA O'Brien, WA Treanor, JJ Weiss, PJ Olson, PE Kaplan, AH Wallace, MR AF Tasker, SA O'Brien, WA Treanor, JJ Weiss, PJ Olson, PE Kaplan, AH Wallace, MR TI Effects of influenza vaccination in HIV-infected adults: a double-blind, placebo-controlled trial SO VACCINE LA English DT Article DE HIV infection; influenza vaccination; quantitative HIV-1 RNA measurement; CD4 lymphocytes ID IMMUNODEFICIENCY-VIRUS INFECTION; ANTIBODY-RESPONSES; IMMUNIZATION; REPLICATION; TYPE-1; ACTIVATION; PLASMA; INDIVIDUALS; LYMPHOCYTES; CHILDREN AB Annual influenza vaccine is recommended for persons with HIV infection, Recent reports indicate that immunizations may increase HII replication in infected individuals, Forty-seven HIV-infected patients were randomized to influenza vaccine or saline placebo using a double blind study design, One month after-vaccination, plasma HIV-I RNA increased in the vaccinated but not placebo group (p=0.029) At 3 months, CD4% dropped an average of 1.6 points in the vaccinated group compared to an increase of 0.1 points in the placebo group (p = 0.039), Patients on stable antiretroviral regimens had CD4% drop an average of 2.3 points in the vaccinated group at 3 months versus 0.1 points in the placebo group (p = 0.015), It is concluded that HIV-infected patients are at risk for increased HIV replication and decreases in CD4% following influenza vaccination. Since influenza has not been associated with significant morbidity in this population, further study of routine influenza vaccination for HIV-infected patients is warranted. (C) 1998 Published by Elsevier-Science Ltd. All rights reserved. C1 USN, Med Ctr, Dept Internal Med, Div Infect Dis, San Diego, CA 92134 USA. USN, Med Ctr, Div Clin Invest, San Diego, CA 92134 USA. Univ Calif Los Angeles, Sch Med, Dept Med, Los Angeles, CA 90024 USA. W Los Angeles Vet Affairs Med Ctr, Dept Med, Los Angeles, CA 90073 USA. Univ Rochester, Med Ctr, Infect Dis Unit, Rochester, NY 14627 USA. USN, Med Ctr, Environm & Prevent Med Unit 5, San Diego, CA 92134 USA. Univ Calif Los Angeles, Sch Med, Dept Immunol & Microbiol, Los Angeles, CA 90024 USA. RP Tasker, SA (reprint author), USN, Med Ctr, Dept Internal Med, Div Infect Dis, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 31 TC 70 Z9 76 U1 0 U2 1 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 MAY-JUN PY 1998 VL 16 IS 9-10 BP 1039 EP 1042 DI 10.1016/S0264-410X(97)00275-2 PG 4 WC Immunology; Medicine, Research & Experimental SC Immunology; Research & Experimental Medicine GA ZV083 UT WOS:000074266800028 PM 9682356 ER PT J AU Miles, MH AF Miles, MH TI Reply to "examination of claims of Miles et al. in Pons-Fleischmann-type cold fusion experiments" SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID EXCESS POWER; PALLADIUM CATHODES; HELIUM PRODUCTION; ELECTROLYSIS; WATER; D2O; RADIATION; DEUTERIUM; BEHAVIOR; SYSTEM C1 USN, Air Warfare Ctr, Weap Div, Res & Technol Div,Chem & Mat Branch, China Lake, CA 93555 USA. RP Miles, MH (reprint author), USN, Air Warfare Ctr, Weap Div, Res & Technol Div,Chem & Mat Branch, China Lake, CA 93555 USA. NR 18 TC 6 Z9 6 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 30 PY 1998 VL 102 IS 18 BP 3642 EP 3646 DI 10.1021/jp961751j PG 5 WC Chemistry, Physical SC Chemistry GA ZN306 UT WOS:000073632700042 ER PT J AU Miles, MH AF Miles, MH TI Reply to "an assessment of claims of excess heat in cold fusion calorimetry" SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article C1 USN, Air Warfare Ctr, Weap Div, Chem & Mat Branch,Res & Technol Div, China Lake, CA 93555 USA. RP Miles, MH (reprint author), USN, Air Warfare Ctr, Weap Div, Chem & Mat Branch,Res & Technol Div, China Lake, CA 93555 USA. NR 5 TC 2 Z9 2 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 30 PY 1998 VL 102 IS 18 BP 3648 EP 3648 DI 10.1021/jp981526x PG 1 WC Chemistry, Physical SC Chemistry GA ZN306 UT WOS:000073632700044 ER PT J AU Chavko, M Braisted, JC Outsa, NJ Harabin, AL AF Chavko, M Braisted, JC Outsa, NJ Harabin, AL TI Role of cerebral blood flow in seizures from hyperbaric oxygen exposure SO BRAIN RESEARCH LA English DT Article DE oxygen toxicity; NMDA receptor; glutamate; nitric oxide synthase; AMPA receptor ID NITRIC-OXIDE SYNTHASE; RECEPTOR ANTAGONISTS; GLUCOSE-UTILIZATION; AMINO-ACID; ANESTHETIZED RATS; TOXICITY; BRAIN; ANTICONVULSANT; INHIBITION; EPILEPSY AB Hyperbaric O-2 exposure causes seizures by an unknown mechanism. Cerebral blood flow (CBF) may affect seizure latency, although no studies have demonstrated a direct relationship. Awake rats (male, Sprague-Dawley, 350-450 g), instrumented for measuring electroencephalographic activity (EEG) and CBF (laser-Doppler flowmetry), were exposed to 100% O-2 at 4 or 5 atm (gauge pressure) until EEG seizures. Compression with O-2 caused vasoconstriction to about 70% of control flow that was maintained for various times. CBF then suddenly, but transiently, increased at a time that was reliably related to seizure latency(r = 0.8, p < 0.01). Additional animals were treated with agents that have diverse pharmacology and their effects on CBF and latency were measured. Glutamate receptor antagonists MK-801 (1 or 4 mg/kg) and ketamine (20-100 mg/kg) significantly increased CBF by 60-80% and decreased seizure latency from about 17 +/- 8 min (+/-S.D.) in controls to 5 +/- 1 and 6 +/- 2 min, respectively. In opposite, a nitric oxide synthase (NOS) inhibitor, N-nitro-L-arginine (NNA)(25 mg/kg) decreased CBF by about 25% and increased time to seizure to 60 +/- 16 min. if these effects occur in humans, non-invasive measurement of CBF could potentially improve the safety and reliability of hyperbaric O-2 usage in clinical and diving applications. It also appears that the effect of drugs on seizure latency can be explained, at least in part, by their effect on CBF. (C) 1998 Elsevier Science B.V. C1 USN, Med Res Inst, Bethesda, MD 20814 USA. RP Chavko, M (reprint author), USN, Med Res Inst, Code 0511,8901 Wisconsin Ave, Bethesda, MD 20814 USA. NR 43 TC 53 Z9 58 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0006-8993 J9 BRAIN RES JI Brain Res. PD APR 27 PY 1998 VL 791 IS 1-2 BP 75 EP 82 DI 10.1016/S0006-8993(98)00083-3 PG 8 WC Neurosciences SC Neurosciences & Neurology GA ZP929 UT WOS:000073802600010 PM 9593832 ER PT J AU Manos, P Custer, TL Pancrazio, JJ Coulombe, MG Stenger, DA Schaudies, RP AF Manos, P Custer, TL Pancrazio, JJ Coulombe, MG Stenger, DA Schaudies, RP TI Cultured neural networks on microelectrode arrays as an activity-based biosensor. SO FASEB JOURNAL LA English DT Meeting Abstract C1 SAIC, Biotechnol Res & Applicat Div, Frederick, MD USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC USA. RI Pancrazio, Joseph/M-3206-2015 OI Pancrazio, Joseph/0000-0001-8276-3690 NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 24 PY 1998 VL 12 IS 8 SU S MA 932 BP A1471 EP A1471 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 260QN UT WOS:000083961501088 ER PT J AU Tadaki, DK Williams, A Lee, KP Harlan, DM AF Tadaki, DK Williams, A Lee, KP Harlan, DM TI Cloning and characterization of porcine CD80 SO FASEB JOURNAL LA English DT Meeting Abstract C1 USN, Med Res Inst, Bethesda, MD USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 24 PY 1998 VL 12 IS 8 SU S MA 870 BP A1460 EP A1460 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 260QN UT WOS:000083961501022 ER PT J AU Owrutsky, JC Baronavski, AP AF Owrutsky, JC Baronavski, AP TI Ultrafast studies of the photodissociation of the acetone 3s Rydberg state at 195 nm: Formation and unimolecular dissociation of the acetyl radical SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MULTIPHOTON IONIZATION; EMISSION-SPECTROSCOPY; STEPWISE DISSOCIATION; TRANSLATIONAL ENERGY; ROTATIONAL-STATE; ALPHA-CLEAVAGE; DYNAMICS; DISTRIBUTIONS; PHOTOFRAGMENTATION; PHOTOPHYSICS AB Ultrafast deep UV mass-resolved photoionization spectroscopy has been used to investigate the photodissociation dynamics of the 3s Rydberg state of acetone. Single photon excitation at 193-195 nm is followed by single photon (at 260 nm) and two photon (at 390 nm) ionization and the signal is measured for both the acetone and acetyl photoions. The acetone Rydberg state lifetime determined from both single and two photon detection is surprisingly long, 4.7 +/- 0.2 ps. The higher probe energy for two photon ionization results in a lower minimum acetyl internal energy for ionization, so that part of the measured signal is due to neutral acetyl dissociation dynamics rather than only dissociative ionization of excited state acetone (which is the case for single photon ionization at 260 nn). The secondary dissociation rate of the neutral acetyl intermediate is measured, clearly establishing that photodissociation via the first Rydberg state of acetone occurs by a sequential dissociation mechanism. The acetyl dissociation occurs with a characteristic time of 3.1 +/- 0.5 ps. Based on RRKM (Rice-Ramsperger-Kassel-Marcus) calculations, this suggests an average acetyl internal energy of similar to 25 kcal/mole. The long lifetime of the 3s Rydberg state suggests that the dissociation dynamics may be described in terms of a fully statistical dissociation mechanism. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Owrutsky, JC (reprint author), USN, Res Lab, Div Chem, Code 6111, Washington, DC 20375 USA. EM jeff.owrutsky@nrl.navy.mil RI Owrutsky, Jeffrey/K-7649-2012; Lee, Yuan-Pern/F-7938-2012 OI Lee, Yuan-Pern/0000-0001-6418-7378 NR 39 TC 41 Z9 41 U1 1 U2 7 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 APR 22 PY 1998 VL 108 IS 16 BP 6652 EP 6659 DI 10.1063/1.476080 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZJ230 UT WOS:000073192500016 ER PT J AU Mowrey, RC Kroes, GJ Baerends, EJ AF Mowrey, RC Kroes, GJ Baerends, EJ TI Dissociative adsorption of H-2 on Cu(100): Fixed-site calculations for impact at hollow and top sites SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DEPENDENT QUANTUM DYNAMICS; POTENTIAL-ENERGY SURFACE; WAVE PACKET APPROACH; ASSOCIATIVE DESORPTION; SCHRODINGER-EQUATION; CU(111) SURFACE; VIBRATIONAL-EXCITATION; REACTIVE SCATTERING; MOLECULAR PHOTOFRAGMENTATION; TRANSLATIONAL ENERGY AB The reaction of H-2 on Cu(100) is studied using a wave-packet method to solve a four-dimensional quantum mechanical model for impact on the high-symmetry hollow and top sites. The potential energy surface (PES) is a fit to the results of density functional calculations treating a periodic overlayer of Hz on a Cu slab. The dynamics calculations include motion in the azimuthal coordinate although the PES does not depend on phi for impact on the top and hollow sites. Large dissociation probabilities (similar to 0.9) are found for impact at the hollow site but those for impact at the top site are lower (similar to 0.3). Dissociation probabilities for molecules incident with "helicoptering" motion (m(j) =j) are larger than those for molecules with "cartwheeling" motion (m(j) = 0). This differs from the results of previous calculations for impact at the azimuthally corrugated bridge site which predicted comparable probabilities for the two orientations of incident molecules. The dissociation probabilities from fixed-site calculations at the different impact sites are combined to yield an averaged probability which is compared with experiment and the results of six-dimensional quantum calculations. Vibrationally inelastic scattering is predicted to occur primarily for impact at the top site. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Theoret Chem Sect, Washington, DC 20375 USA. Rijksuniv Leiden, Gorlaeus Labs, LIC, NL-2300 RA Leiden, Netherlands. Free Univ Amsterdam, NL-1081 HV Amsterdam, Netherlands. RP Mowrey, RC (reprint author), USN, Res Lab, Theoret Chem Sect, Code 6179, Washington, DC 20375 USA. RI Baerends, Evert Jan/F-7206-2011 OI Baerends, Evert Jan/0000-0002-3045-4906 NR 66 TC 18 Z9 18 U1 0 U2 5 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 APR 22 PY 1998 VL 108 IS 16 BP 6906 EP 6915 DI 10.1063/1.476105 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZJ230 UT WOS:000073192500043 ER PT J AU Kozikowski, AP Araldi, GL Flippen-Anderson, J George, C Pshenichkin, S Surina, E Wroblewski, J AF Kozikowski, AP Araldi, GL Flippen-Anderson, J George, C Pshenichkin, S Surina, E Wroblewski, J TI Synthesis and metabotropic glutamate receptor activity of a 2-aminobicyclo[3.2.0]heptane-2,5-dicarboxylic acid, a molecule possessing an extended glutamate conformation SO BIOORGANIC & MEDICINAL CHEMISTRY LETTERS LA English DT Article AB A photochemical approach to the synthesis of the aminobicycloheptane 6a is reported. This compound assumes an extended glutamate conformation, and for this reason was created to further probe the structural features relevant to achieving selectivity for the subtypes of the metabotropic glutamate family of receptors. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Georgetown Univ, Med Ctr, Inst Cognit & Computat Sci, Drug Discovery Program, Washington, DC 20007 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. Georgetown Univ, Med Ctr, Dept Pharmacol, Washington, DC 20007 USA. RP Kozikowski, AP (reprint author), Georgetown Univ, Med Ctr, Inst Cognit & Computat Sci, Drug Discovery Program, 3970 Reservoir Rd NW, Washington, DC 20007 USA. NR 20 TC 7 Z9 7 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0960-894X J9 BIOORG MED CHEM LETT JI Bioorg. Med. Chem. Lett. PD APR 21 PY 1998 VL 8 IS 8 BP 925 EP 930 DI 10.1016/S0960-894X(98)00146-2 PG 6 WC Chemistry, Medicinal; Chemistry, Organic SC Pharmacology & Pharmacy; Chemistry GA ZL750 UT WOS:000073467100008 PM 9871513 ER PT J AU Choi, LS Collins, GE AF Choi, LS Collins, GE TI Triple fluorescence of 4-(1,4,8,11-tetraazacyclotetradecyl)benzonitrile SO CHEMICAL COMMUNICATIONS LA English DT Article ID ANOMALOUS FLUORESCENCE; CHARGE-TRANSFER AB Triple fluorescence is observed for DMABN-cyclam in EtOH, corresponding to a locally excited (LE) singlet state; a twisted intramolecular charge transfer (TICT) state, and an intramolecular exciplex (E). C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Collins, GE (reprint author), USN, Res Lab, Div Chem, Washington, DC 20375 USA. NR 9 TC 16 Z9 16 U1 0 U2 3 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE CB4 4WF, CAMBS, ENGLAND SN 1359-7345 J9 CHEM COMMUN JI Chem. Commun. PD APR 21 PY 1998 IS 8 BP 893 EP 894 DI 10.1039/a801749b PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA ZK224 UT WOS:000073297800018 ER PT J AU Selinger, JV Selinger, RLB AF Selinger, JV Selinger, RLB TI Cooperative chiral order in polyisocyanates: New statistical problems SO MACROMOLECULES LA English DT Article ID MOLECULAR-WEIGHT DEPENDENCE; MACROMOLECULAR STEREOCHEMISTRY; RANDOM COPOLYMERS; OPTICAL-ROTATION; ISOCYANATE); MONOMERS; SENSE AB Polyisocyanates with a random sequence of (R) and (S) pendant groups follow a chiral "majority rule": the optical activity of the polymers is dominated by whichever enantiomer is in the majority. In earlier work, this effect was explained theoretically through a mapping of the polymer system onto the random-field Ising model. Here, the theory is extended to a wider class of heteropolymers. The theory predicts that the introduction of achiral pendant groups into the random sequence should have remarkably little effect on the sharpness of the majority-rule curve. It further predicts that correlations in the handedness of neighboring pendant groups should reduce the sharpness of the majority-rule effect, while anticorrelations should enhance the sharpness of this effect. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. RP Selinger, JV (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Code 6900,4555 Overlook Ave SW, Washington, DC 20375 USA. RI Selinger, Jonathan/D-1445-2010; OI Selinger, Jonathan/0000-0002-4982-2457; Selinger, Robin/0000-0002-6519-9685 NR 18 TC 26 Z9 26 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD APR 21 PY 1998 VL 31 IS 8 BP 2488 EP 2492 DI 10.1021/ma971783k PG 5 WC Polymer Science SC Polymer Science GA ZK615 UT WOS:000073342900013 ER PT J AU Colson, WB AF Colson, WB TI Short-wavelength free-electron lasers in 1997 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 19th International Free Electron Laser Conference/4th FEL Users Workshop CY AUG 18-21, 1997 CL BEIJING, PEOPLES R CHINA SP Inst Appl Electr, Inst High Energy Phys, China Inst Atomic Energy, Univ Electr Sci & Technol China, Peking Univ, Inst Appl Phys & Computat Math ID IR FEL PROJECT; SUPERCONDUCTING LINAC; SPONTANEOUS EMISSION; RACETRACK MICROTRON; TEST-FACILITY; BEIJING FEL; FELICITA-I; VUV-FEL; AMPLIFICATION; INSTITUTE C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. RP Colson, WB (reprint author), USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. NR 55 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 1998 VL 407 IS 1-3 BP 26 EP 29 DI 10.1016/S0168-9002(97)01360-0 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA ZW290 UT WOS:000074395200007 ER PT J AU Freund, HP Granatstein, VL AF Freund, HP Granatstein, VL TI Long-wavelength free-electron lasers in 1997 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 19th International Free Electron Laser Conference/4th FEL Users Workshop CY AUG 18-21, 1997 CL BEIJING, PEOPLES R CHINA SP Inst Appl Electr, Inst High Energy Phys, China Inst Atomic Energy, Univ Electr Sci & Technol China, Peking Univ, Inst Appl Phys & Computat Math ID WIGGLER; AMPLIFIER AB A summary of the current status and most important future directions for long wavelength ( greater than or equal to 0.5 mm) free-electron lasers are presented. The distinction between long and short wavelength is a natural one. For example, space-charge effects may be important for the high currents typically employed at long wavelengths, and the dominant interaction mechanism is often coherent Raman scattering. In addition, dispersion due to the dielectric effects and finite transverse dimensions in the drift tubes and cavities are important at longer wavelengths. The principal goals at long wavelengths are to achieve much higher average powers with good overall efficiency in a compact design, and the highest average power produced in a FEL to date (36W) has been recorded in the Ku-band. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. RP Granatstein, VL (reprint author), Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. NR 31 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 1998 VL 407 IS 1-3 BP 30 EP 33 DI 10.1016/S0168-9002(97)01361-2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA ZW290 UT WOS:000074395200008 ER PT J AU Tavani, M Kniffen, D Mattox, JR Paredes, JM Foster, RS AF Tavani, M Kniffen, D Mattox, JR Paredes, JM Foster, RS TI The variable gamma-ray source 2CG 135+01 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays, observations; gamma rays, theory ID RADIO; LSI+61-DEGREES-303 AB The EGRET instrument on board the Compton Gamma Ray Observatory has detected about 150 sources above 100 MeV. Slightly less than half of these sources have been identified either as active galactic nuclei (AGNs) associated with spectrally flat radio-loud sources of the blazar type or as isolated young/intermediate-age pulsars. Except for rotational modulation, the gamma-ray flux of pulsars does not display significant variation, whereas blazars show variability on timescales as short as similar to 7 hr. We show here that one of the most prominent unidentified gamma-ray sources near the Galactic plane, 2CG 135+01 (first discovered by the COS B satellite), does not fit into either of these two classes. By comparing different EGRET observations, we establish with 98.8% confidence that the gamma-ray flux from 2CG 135+01 is time variable. This is inconsistent with the constant flux observed from isolated gamma-ray pulsars. No potential spectrally flat radio-loud AGN counterpart exists for this source. We show that 2CG 135+01 belongs to a new class of variable gamma-ray emitters in the Galactic plane, a class that also includes the recently discovered nonblazar gamma-ray transient GRO J1838-04. C1 Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. CNR, Inst Fis Cosm, I-20133 Milan, Italy. Hampden Sydney Coll, Hampden Sydney, VA 23943 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Greenbelt, MD 20771 USA. Boston Univ, Dept Astron, Boston, MA 02215 USA. Univ Barcelona, E-08028 Barcelona, Spain. USN, Res Lab, Washington, DC 20375 USA. RP Columbia Univ, Columbia Astrophys Lab, 538 W 120th St, New York, NY 10027 USA. NR 31 TC 51 Z9 51 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 APR 20 PY 1998 VL 497 IS 2 BP L89 EP L91 DI 10.1086/311281 PN 2 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZJ200 UT WOS:000073189500008 ER PT J AU Taylor, JA AF Taylor, JA TI Mass function gradients and the need for dark matter SO ASTROPHYSICAL JOURNAL LA English DT Article DE dark matter; galaxies, evolution; galaxies, halos; galaxies, kinematics and dynamics; galaxies, luminosity function, mass function; Magellanic Clouds ID HUBBLE-SPACE-TELESCOPE; SURFACE PHOTOMETRY; STAR FORMATION; GALACTIC DISK; STELLAR; GALAXY; DENSITY; CLOUD; M82; SUN AB There is both theoretical and empirical evidence that the initial mass function (IMF) may be a function of the local star formation conditions. In particular, the IMF is predicted to flatten with increasing local luminosity density rho(l), with the formation of massive stars being preferentially enhanced in brighter regions. In R136, the bright stellar cluster in 30 Doradus, the IMF gradient is partial derivative Gamma/partial derivative log rho(l) = 0.28 +/- 0.06, where Gamma is the slope of the IMF. If such IMF gradients are indeed general features of galaxies, this implies that several previous astrophysical measurements, such as the surface mass densities of spirals (obtained assuming constant mass-to-light ratios), were plagued by substantial systematic errors. In this Letter, calculations that account for possible IMF gradients are presented for surface densities of spiral galaxies. Compared with previous estimates, the mass surface densities corrected for IMF gradients are higher in the outer regions of the disks. For a model based on the Milky Way but with an IMF scaled according to R136, the rotation curve without the traditional dark halo component falls with Galactocentric radius, although slower than it would without IMF gradients. For a second model of the Milky Way in which the IMF gradient is increased to 0.42, the rotation curve is approximately flat in the outer disk, with a rotational velocity below similar or equal to 220 km s(-1) only before the traditional dark halo component is added. For a third model in which substantial arm/interarm density contrasts are additionally assumed, the solar vicinity mass density drops to 0.10 M-. pc(-3), which is consistent with observations. These results, if generalizable to other galaxies, not only call into question the assertion that dark matter halos are compatible with the flat rotation curves of spiral galaxies but also may clarify our understanding of a wide variety of other astrophysical phenomena such as the G dwarf problem, metallicity gradients, and the Tully-Fisher relation. C1 USN Acad, Dept Phys, Annapolis, MD 21402 USA. RP Taylor, JA (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Code 661, Greenbelt, MD 20771 USA. NR 35 TC 5 Z9 5 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 APR 20 PY 1998 VL 497 IS 2 BP L81 EP L84 DI 10.1086/311280 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZJ200 UT WOS:000073189500006 ER PT J AU Mazin, II AF Mazin, II TI Interpretation of the femtosecond optical response of YBa2Cu3O7-delta SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-TC SUPERCONDUCTORS; COHERENT PHONONS; DISPLACIVE EXCITATION; THIN-FILMS C1 George Mason Univ, CSI, Washington, DC 20375 USA. NRL, Washington, DC 20375 USA. RP Mazin, II (reprint author), George Mason Univ, CSI, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008 NR 8 TC 6 Z9 6 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 20 PY 1998 VL 80 IS 16 BP 3664 EP 3664 DI 10.1103/PhysRevLett.80.3664 PG 1 WC Physics, Multidisciplinary SC Physics GA ZJ325 UT WOS:000073202700063 ER PT J AU Uhm, HS Choi, EH Ko, JJ Cho, GS Shin, HM AF Uhm, HS Choi, EH Ko, JJ Cho, GS Shin, HM TI Ion density of plasma channel induced by relativistic electron beam from a gas-filled diode SO PHYSICS LETTERS A LA English DT Article AB The ion density of a plasma channel induced by a relativistic electron beam is investigated experimentally under various gas pressures. The electron beam generated from a gas-filled foilless diode propagates through a gas-filled drift tube. The ion density is obtained from the magnetic decay time of the plasma current following the electron-beam current. A theoretical model is developed to explain the experimental observation. The experimental data agree well with an analysis of the theoretical model. Published by Elsevier Science B.V. C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. Kwangwoon Univ, Dept Electrophys, Charged Particle Beam & Plasma Lab, Seoul 139701, South Korea. RP Uhm, HS (reprint author), USN, Ctr Surface Warfare, Carderock Div, 9500 MacArthur Blvd, W Bethesda, MD 20817 USA. NR 3 TC 16 Z9 16 U1 0 U2 1 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 APR 20 PY 1998 VL 241 IS 1-2 BP 105 EP 109 DI 10.1016/S0375-9601(98)00106-6 PG 5 WC Physics, Multidisciplinary SC Physics GA ZH792 UT WOS:000073148100017 ER PT J AU Kowtha, VC Bryant, HJ Pancrazio, JJ Stenger, DA AF Kowtha, VC Bryant, HJ Pancrazio, JJ Stenger, DA TI Influence of extracellular matrix proteins on membrane potentials and excitability in NG108-15 cells SO NEUROSCIENCE LETTERS LA English DT Article DE collagen; excitability; extracellular matrix; laminin; NG108-15; serum-free media ID BASEMENT-MEMBRANE; LAMININ; EXPRESSION AB Previous studies have demonstrated that components of the extracellular matrix can induce neurite extension and cell adhesion in the neuroblastoma x glioma hybrid cell line, NG108-15. Using standard intracellular recording techniques, we examined the resting membrane potential (RMP) and membrane excitability of NG108-15 cells differentiated under serum-free media with representative extracellular matrix (ECM) protein components as the substrate. Surfaces coated with collagen IV and a laminin-l synthetic peptide induced a significantly (P < 0.05) more hyperpolarized RMP than control polystyrene surfaces. For example, after greater than or equal to 8 days in culture NG108-15 cells plated on polystyrene exhibited a RMP of -33.2 +/- 0.8 mV (mean +/- SEM, n = 158 cells) whereas cells cultured on the laminin-l peptide C16 and collagen IV showed a RMP of -37.6 +/- 0.7 mV (n = 157) and -37.5 +/- 1.5 mV (n = 68), respectively. Furthermore, the proportions of cells on ECM substrates showing membrane excitability, i.e. evoked action potentials (APs) and the capability for regular firing, were significantly greater compared to those cells cultured on polystyrene. Among excitable cells cultured on the different substrates, characteristics of the action potentials, such as AP duration, amplitude, and the maximum rate of rise, dV/dt(MAX), were examined in detail. While little or no differences were observed between polystyrene and the laminin-l peptide groups, significant differences in the AP parameters were apparent for collagen IV. For example, dV/dt(MAX) for polystyrene and the laminin-l peptide C16 were only 71.7 +/- 24.5 V/s (n = 11) and 59.0 +/- 8.9 V/s (n = 9), respectively, whereas cells cultured on collagen IV surfaces exhibited a dV/dt(MAX) reaching 156.1 +/- 22.0 V/s (n = 7). These data support a role for ECM components in the maintenance of the RMP and membrane excitability in NG108-15 cells. (C) 1998 Elsevier Science Ireland Ltd. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. Uniformed Serv Univ Hlth Sci, Dept Physiol, Bethesda, MD 20814 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 21 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0304-3940 J9 NEUROSCI LETT JI Neurosci. Lett. PD APR 17 PY 1998 VL 246 IS 1 BP 9 EP 12 DI 10.1016/S0304-3940(98)00193-1 PG 4 WC Neurosciences SC Neurosciences & Neurology GA ZL009 UT WOS:000073389700003 PM 9622195 ER PT J AU Pauls, T AF Pauls, T TI Natron trade, 2000 BC SO SCIENCE LA English DT Letter C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Pauls, T (reprint author), USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. EM pauls@rsd.nrl.navy.mil NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD APR 17 PY 1998 VL 280 IS 5362 BP 361 EP 361 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZH907 UT WOS:000073159600006 ER PT J AU Brann, OS McHutchison, JG AF Brann, OS McHutchison, JG TI The effect of combination therapy (interferon and ribavirin) on peripheral blood lymphocyte and leukocyte counts. SO GASTROENTEROLOGY LA English DT Meeting Abstract C1 Scripps Clin & Res Fdn, Div GI Hepatol, La Jolla, CA 92037 USA. Naval Med Centerm, Div Gastroenterol, San Diego, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0016-5085 J9 GASTROENTEROLOGY JI Gastroenterology PD APR 15 PY 1998 VL 114 IS 4 SU S MA L0068 BP A1215 EP A1215 PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA ZH263 UT WOS:000073089604931 ER PT J AU Brensing, KA Textor, J Schiedermaier, P Hinterthaner, B Wolfram, G Kramer, HJ Schild, H Sauerbruch, T AF Brensing, KA Textor, J Schiedermaier, P Hinterthaner, B Wolfram, G Kramer, HJ Schild, H Sauerbruch, T TI Acute and short-term changes in renal and systemic levels of renin, noradrenalin and endothelin after portal decompression by TIPS. SO GASTROENTEROLOGY LA English DT Meeting Abstract C1 Navl Med Centerm, Div Gastroenterol, San Diego, CA USA. Scripps Clin & Res Fdn, Div GI Hepatol, La Jolla, CA 92037 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0016-5085 J9 GASTROENTEROLOGY JI Gastroenterology PD APR 15 PY 1998 VL 114 IS 4 SU S MA L0069 BP A1215 EP A1215 PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA ZH263 UT WOS:000073089604929 ER PT J AU Koch, KL Muth, E Bingaman, S Stern, RM AF Koch, KL Muth, E Bingaman, S Stern, RM TI Abnormal and normal electrogastrograms (EGG) in patients with functional dyspepsia. SO GASTROENTEROLOGY LA English DT Meeting Abstract C1 USN, Aerosp Med Res Lab, Pensacola, FL USA. Penn State Univ, Dept Med, University Pk, PA 16802 USA. Penn State Univ, Dept Psychol, University Pk, PA 16802 USA. Penn State Univ, Milton S Hershey Med Ctr, Dept Med, Hershey, PA 17033 USA. Penn State Univ, Dept Surg, Hershey, PA 17033 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0016-5085 J9 GASTROENTEROLOGY JI Gastroenterology PD APR 15 PY 1998 VL 114 IS 4 SU S MA G0739 BP A180 EP A181 DI 10.1016/S0016-5085(98)80733-6 PN 2 PG 2 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA ZH263 UT WOS:000073089600733 ER PT J AU Muth, ER Koch, KL Bingaman, SK Stern, RM AF Muth, ER Koch, KL Bingaman, SK Stern, RM TI The clinical utility of symptoms assessment in patients with functional dyspepsia SO GASTROENTEROLOGY LA English DT Meeting Abstract C1 Penn State Univ, Dept Psychol, University Pk, PA 16802 USA. Penn State Univ, Dept Med, University Pk, PA 16802 USA. USN, Aerosp Med Res Lab, Pensacola, FL USA. Penn State Univ, Dept Med, Hershey, PA 17033 USA. Penn State Univ, Dept Psychol, Hershey, PA 17033 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0016-5085 J9 GASTROENTEROLOGY JI Gastroenterology PD APR 15 PY 1998 VL 114 IS 4 SU S MA G3324 BP A808 EP A809 DI 10.1016/S0016-5085(98)83299-X PN 2 PG 2 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA ZH263 UT WOS:000073089603299 ER PT J AU Schoenfeld, P Lipscomb, S Dominguez, J Crook, J Holmes, L Piorkowski, M Allaire, J Johnston, M Butler, J Hammond, A Cruess, D Rex, D AF Schoenfeld, P Lipscomb, S Dominguez, J Crook, J Holmes, L Piorkowski, M Allaire, J Johnston, M Butler, J Hammond, A Cruess, D Rex, D TI Accuracy of polyp detection during screening flexible sigmoidoscopy by gastroenterologists and nurse endoscopists: A randomized controlled trial. SO GASTROENTEROLOGY LA English DT Meeting Abstract C1 USN, Med Ctr, Div Gastroenterol, Bethesda, MD 20814 USA. Uniformed Serv Univ Hlth Sci, Dept Epidemiol & Biostat, Bethesda, MD 20814 USA. Indiana Univ, Med Ctr, Div Gastroenterol, Indianapolis, IN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0016-5085 J9 GASTROENTEROLOGY JI Gastroenterology PD APR 15 PY 1998 VL 114 IS 4 SU S MA G2786 BP A674 EP A675 DI 10.1016/S0016-5085(98)82766-2 PN 2 PG 2 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA ZH263 UT WOS:000073089602766 ER PT J AU Vurgaftman, I Meyer, JR Dell, JM Fisher, TA Faraone, L AF Vurgaftman, I Meyer, JR Dell, JM Fisher, TA Faraone, L TI Simulation of mid-infrared HgTe/CdTe quantum-well vertical-cavity surface-emitting lasers SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID DISTRIBUTED BRAGG REFLECTORS; CHEMICAL-VAPOR-DEPOSITION; OPTICAL-PROPERTIES; HGCDTE; DESIGN; HETEROSTRUCTURES; SUPERLATTICES; RESISTANCE; MIRRORS; ARRAYS AB We theoretically show the feasibility of optically and electrically pumped Hg-based vertical-cavity surface-emitting lasers (VCSELs) that emit at midwave-infrared wavelengths up to thermoelectric cooler temperatures. The maximum operating temperature is significantly enhanced by employing a multiple quantum-well active region with very thin (20-30 Angstrom) HgTe wells engineered to yield a strong suppression of both Auger recombination and intervalence foe-carrier absorption. Hg0.65Cd0.35Te/Hg0.1Cd0.9Te distributed Bragg reflectors are employed for one or both of the mirrors defining the optical cavity. Detailed numerical simulations of VCSELs emitting at lambda approximate to 4.3 mu m predict that for optical pumping at 1.06 mu m, a maximum operating temperature of 220 K should be achievable for pulsed operation and 160 K in cw mode, with a cw power output of up to 2.6 mW per array element at 100 K. Injection VCSELs are predicted to operate up to 200 K for pulsed operation and 105 K for quasi-cw with a 10% duty cycle. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Western Australia, Nedlands, WA 6907, Australia. RP Vurgaftman, I (reprint author), USN, Res Lab, Code 5613, Washington, DC 20375 USA. RI Dell, John/B-2389-2013 OI Dell, John/0000-0003-2801-3519 NR 33 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1998 VL 83 IS 8 BP 4286 EP 4291 DI 10.1063/1.367187 PG 6 WC Physics, Applied SC Physics GA ZJ989 UT WOS:000073273900049 ER PT J AU Hurlburt, HE Metzger, EJ AF Hurlburt, HE Metzger, EJ TI Bifurcation of the Kuroshio Extension at the Shatsky Rise SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID OCEANIC GENERAL-CIRCULATION; NORTH PACIFIC; MESOSCALE EDDIES; ALTIMETER DATA; CURRENT SYSTEM; MODEL; DYNAMICS; VARIABILITY; SEA; SIMULATION AB A 1/16 degrees six-layer Pacific Ocean model north of 20 degrees S is used to investigate the bifurcation of the Kuroshio Extension at the main Shatsky Rise and the pathway of the northern branch from the bifurcation to the subarctic front. Upper ocean-topographic coupling via a mixed barotropic-baroclinic instability is essential to this bifurcation and to the formation and mean pathway of the northern branch as are several aspects of the Shatsky Rise complex of topography and the latitude of the Kuroshio Extension in relation to the topography. The flow instabilities transfer energy to the abyssal layer where it is constrained by geostrophic contours of the bottom topography. The topographically constrained abyssal currents in turn steer upper ocean currents, which do not directly impinge on the bottom topography. This includes steering of mean pathways. Obtaining sufficient coupling requires very fine resolution of mesoscale variability and sufficient eastward penetration of the Kuroshio as an unstable inertial jet. Resolution of 1/8 degrees for each variable was not sufficient in this case. The latitudinal extent of the main Shatsky Rise (31 degrees N-36 degrees N) and the shape of the downward slope on the north side are crucial to the bifurcation at the main Shatsky Rise, with both branches passing north of the peak. The well-defined, relatively steep and straight eastern edge of the Shatsky Rise topographic complex (30 degrees N-42 degrees N) and the southwestward abyssal flow along it play a critical role in forming the rest of the Kuroshio northern branch which flows in the opposite direction. A deep pass between the main Shatsky Rise and the rest of the ridge to the northeast helps to link the northern fork of the bifurcation at the main rise to the rest of the northern branch. Two 1/16 degrees "identical twin" interannual simulations forced by daily winds 1981-1995 show that the variability in this region is mostly nondeterministic on all timescales that could be examined (up to 7 years in these 15-year simulations). A comparison of climatologically forced and interannual simulations over the region 150 degrees E-180 degrees E, 29 degrees N-47 degrees N showed greatly enhanced abyssal and upper ocean eddy kinetic energy and much stronger mean abyssal currents east of the Emperor Seamount Chain (about 170 degrees E) in the interannual simulations but little difference west of 170 degrees E. This greatly enhanced the upper ocean-topographic coupling in the interannual simulations east of 170 degrees E. This coupling affected the latitudinal positioning of the eastward branches of the Kuroshio Extension and tended to reduce latitudinal movement compared to the climatologically forced simulation, including a particularly noticeable impact from the Hess Rise. Especially in the interannual simulations, effects of almost all topographic features in the region could be seen in the mean upper ocean currents (more so than in instantaneous currents), including meanders and bifurcations of major and minor currents, closed circulations, and impacts from depressions and rises of large and small amplitudes. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP USN, Res Lab, Code 7323, Stennis Space Ctr, MS 39529 USA. EM hurlburt@nrlssc.navy.mil; metzger@nrlssc.navy.mil NR 34 TC 35 Z9 35 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 EI 2169-9291 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD APR 15 PY 1998 VL 103 IS C4 BP 7549 EP 7566 DI 10.1029/97JC02723 PG 18 WC Oceanography SC Oceanography GA ZH476 UT WOS:000073114800006 ER PT J AU Bruce, JG Kindle, JC Kantha, LH Kerling, JL Bailey, JF AF Bruce, JG Kindle, JC Kantha, LH Kerling, JL Bailey, JF TI Recent observations and modeling in the Arabian Sea Laccadive High region SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID NORTHEAST MONSOON AB Recent observations that include an airborne expendable bathythermograph (AXBT) survey and coincident satellite altimeter measurements together with a high-resolution numerical simulation indicate that the Laccadive High, an anticyclonic circulating feature that forms off the SW coast of India during the NE monsoon, is comprised of multiple eddies. It is hypothesized that in addition to local and remote seasonal forcing, the Laccadive High region is influenced by an intraseasonal signal that originates in the Bay of Bengal. C1 USN, Oceanog Off, Stennis Space Ctr, MS 39522 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Univ Colorado, Colorado Ctr Astrodynam Res, Boulder, CO 80309 USA. RP Bruce, JG (reprint author), Box 482, Woods Hole, MA 02543 USA. NR 7 TC 47 Z9 48 U1 1 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 APR 15 PY 1998 VL 103 IS C4 BP 7593 EP 7600 DI 10.1029/97JC03219 PG 8 WC Oceanography SC Oceanography GA ZH476 UT WOS:000073114800009 ER PT J AU Arnone, RA Ladner, S La Violette, PE Brock, JC Rochford, PA AF Arnone, RA Ladner, S La Violette, PE Brock, JC Rochford, PA TI Seasonal and interannual variability of surface photosynthetically available radiation in the Arabian Sea SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID NORTH-ATLANTIC; SOUTHWEST MONSOON; SOLAR IRRADIANCE; PACIFIC-OCEAN; PHYTOPLANKTON; PARTICLES; MODEL AB The regional and monthly intensity of photosynthetically available radiation (PAR) (350-700 nm) just below the sea surface (Ed(PAR)(-)) for the Arabian Sea is determined from solar irradiance models and 7 years of satellite data (1979-1985), Model results of high spatial resolution (18 km) PAK distribution computed from actual monthly measurements (aerosols, cloud cover, and ozone) displayed small-scale patchiness that is not observed in PAR climatology models. Two elevated PAR periods are observed each year, as opposed to a single elevated period per year observed in the North Atlantic during the summer. When the biannual cycle for each of the 7 years is compared with the 7-year average, interannual changes in intensity and time are observed. Additionally, the PAR cycle is found to vary regionally within the Arabian Sea, The bimodal PAR distribution shows elevated peaks in May and October and minima in December (corresponding to the winter equinox) and July. The second minima occurs at the onset of the southwest monsoon, apparently in response to increased cloud cover and aerosols associated with the monsoon. This summer minima varied latitudinally. It originates in the southern regions (0 degrees-10 degrees latitude) in April and migrates north as the influence of the southwest monsoon moves northward, reaching the northern Oman coast (20 degrees latitude) in August. Additionally, the summer minima is Less pronounced as the southwest monsoon moves northward. Maximum PAR intensity is observed in early spring (preceding the minima), originating in the southern Arabian Sea and extending northward into the central Arabian Sea. The timing of the northward movement of this spring maximum is slightly different each year. The net yearly PAR intensity for each of the 7 years appears to remain approximately the same, despite the interannual variability in the cycle and regional variability. The timing and location of PAR cycles are important since they must be coupled with nutrient availability to understand biological cycles. We determined that for the Arabian Sea, PAR cycles determined by climatology may be inadequate to define the submarine light field and that high-resolution PAR cycles are needed to resolve realistic bio-optical and nutrient cycles. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NOAA, Coastal Serv Ctr, Charleston, SC 29405 USA. Gulf Weather Corp, Stennis Space Ctr, MS 39529 USA. Severdrup Technol Inc, Stennis Space Ctr, MS 39529 USA. Planning Sci Inc, Slidell, LA 70458 USA. RP Arnone, RA (reprint author), USN, Res Lab, Code 7343, Stennis Space Ctr, MS 39529 USA. EM arnone@nrlssc.navy.mil NR 38 TC 10 Z9 10 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 APR 15 PY 1998 VL 103 IS C4 BP 7735 EP 7748 DI 10.1029/97JC03204 PG 14 WC Oceanography SC Oceanography GA ZH476 UT WOS:000073114800020 ER PT J AU Davis, TA Saini, AA Blair, PJ Levine, BL Craighead, N Harlan, DM June, CH Lee, KP AF Davis, TA Saini, AA Blair, PJ Levine, BL Craighead, N Harlan, DM June, CH Lee, KP TI Phorbol esters induce differentiation of human CD34(+) hemopoietic progenitors to dendritic cells: Evidence for protein kinase C-mediated signaling SO JOURNAL OF IMMUNOLOGY LA English DT Article ID COLONY-STIMULATING FACTOR; TUMOR-NECROSIS-FACTOR; ANTIGEN-PRESENTING CELLS; NF-KAPPA-B; HUMAN BLOOD; LANGERHANS CELLS; BONE-MARROW; FACTOR-ALPHA; GM-CSF; SOLUBLE-ANTIGEN AB The intracellular signals that mediate the differentiation of pluripotent hemopoietic progenitors to dendritic cells (DC) are largely undefined. We have found that the phorbol ester PMA by itself induced 47% +/- 8.7% of input human CD34(+) hemopoietic progenitors to differentiate into cells with morphology and surface Ag phenotype characteristic of DC by day 7 of culture, Functionally, PMA-generated DC processed and presented whole soluble Ag and also induced resting T cell proliferation and Ag-specific CTL effector function, Unlike cytokine-driven DC differentiation, PMA suppressed proliferation and induced cell death (in part via apoptosis) in cells that did not differentiate to DC, The effects of PMA were blocked by inhibitors of protein kinase C activation, suggesting a central role for this signaling molecule, PMA-mediated signaling also induced expression of the RelB transcription factor, an NF-kappa B family member implicated in DC differentiation. These findings suggest that phorbol esters activate protein kinase C, which then initiates the terminal component of an intracellular signaling pathway(s) involved in the DC differentiation of CD34(+) hemopoietic progenitors. C1 USN, Med Res Inst, Immune Cell Biol Program, Stem Cell Biol Branch, Bethesda, MD 20889 USA. Uniformed Serv Univ Hlth Sci, Bethesda, MD 20889 USA. RP Lee, KP (reprint author), USN, Med Res Inst, Immune Cell Biol Program, Stem Cell Biol Branch, Bldg 17,Room 214,8901 Wisconsin Ave, Bethesda, MD 20889 USA. EM leek@nmripo.nmri.nnmc.navy.mil RI Levine, Bruce/D-1688-2009 NR 60 TC 55 Z9 58 U1 0 U2 0 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD APR 15 PY 1998 VL 160 IS 8 BP 3689 EP 3697 PG 9 WC Immunology SC Immunology GA ZG143 UT WOS:000072970400010 PM 9558069 ER PT J AU Higgins, J AF Higgins, J TI Outsourcing skepticism SO LIBRARY JOURNAL LA English DT Letter C1 USN, Ctr Naval Anal, Alexandria, VA USA. RP Higgins, J (reprint author), USN, Ctr Naval Anal, Alexandria, VA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD APR 15 PY 1998 VL 123 IS 7 BP 8 EP 8 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA ZH489 UT WOS:000073116200002 ER PT J AU Glaser, ER Kennedy, TA Carlos, WE Freitas, JA Wickenden, AE Koleske, DD AF Glaser, ER Kennedy, TA Carlos, WE Freitas, JA Wickenden, AE Koleske, DD TI Optically detected electron-nuclear double resonance of epitaxial GaN SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC-RESONANCE; SHALLOW DONORS; MICROWAVE PERFORMANCE; WURTZITE GAN; SAPPHIRE; RECOMBINATION; LUMINESCENCE AB Optically detected electron-nuclear double resonance (ODENDOR) experiments at 24 GHz performed on a set of GaN epitaxial layers grown on Al2O3, substrates reveal Ga-69,Ga-71 signals with quadrupole splittings that reflect the crystal structure and degree of local strain. Searches were made between 1.5 and 140 MHz on both the effective-mass (EM) donor and deep defect resonances revealed from optically detected magnetic resonance (ODMR) studies of the 2.2-eV "yellow" emission bands. Strong Ga-69 and Ga-71 lines were found between 7 and 14 MHz on the EM donor resonance from two high-resistivity films (n less than or equal to 1x10(16) cm(-3)), and are attributed to neighboring Ga-69,Ga-71 lattice nuclei. These resonances are split by the local electric-field gradients through the nuclear quadrupole interaction. The quadrupole splittings of 2.16+/-0.08 and 2.40 +/- 0.05 MHz found for Ga-69 in these samples are 15-25 % smaller than those reported for a free-standing bulk platelet and for a bulk powder. Similar signals were not observed on the EM-donor lines from two n-type GaN layers with n greater than or equal to 3x10(16) cm(-3). These concentration-dependence results reveal the ENDOR mechanisms in GaN. ODENDOR was not found on the deep-defect ODMR. Possible reasons for the absence of signals are presented. [S0163-1829(98)00216-1]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Glaser, ER (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 39 TC 12 Z9 12 U1 0 U2 6 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 APR 15 PY 1998 VL 57 IS 15 BP 8957 EP 8965 DI 10.1103/PhysRevB.57.8957 PG 9 WC Physics, Condensed Matter SC Physics GA ZJ480 UT WOS:000073219900042 ER PT J AU Luban, M Luscombe, JH AF Luban, M Luscombe, JH TI Dynamical localization of electrons in an aperiodic superlattice SO PHYSICAL REVIEW B LA English DT Article ID SUBMILLIMETER-WAVE EMISSION; BLOCH OSCILLATIONS; IMPURITY; SYSTEMS; FIELDS AB We derive the analytical form of the time-dependent wave function for a single-band tight-binding model of independent conduction electrons within an aperiodic semiconductor superlattice, created by modifications in the composition of a single layer of an otherwise periodic superlattice. While the wave function for long times is known to feature both diffusive and localized behavior, the latter originating in the superlattice aperiodicity,we provide quantitative results for these features for all values of the time. [S0163-1829(98)03215-9]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. RP Luban, M (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 19 TC 1 Z9 1 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 APR 15 PY 1998 VL 57 IS 15 BP 9043 EP 9049 DI 10.1103/PhysRevB.57.9043 PG 7 WC Physics, Condensed Matter SC Physics GA ZJ480 UT WOS:000073219900052 ER PT J AU Walck, SN Reinecke, TL AF Walck, SN Reinecke, TL TI Exciton diamagnetic shift in semiconductor nanostructures SO PHYSICAL REVIEW B LA English DT Article ID GAAS-GA1-XALXAS QUANTUM WELLS; ENERGY; WIRES AB A method is presented for calculating the diamagnetic coefficient of an exciton in a semiconductor nanostructure. The diamagnetic coefficient characterizes the response of a confined exciton to a weak magnetic field, and gives information about the roles of confinement and of the Coulomb interaction in determining the optical properties. A general formulation is presented for nanostructures of arbitrary size, shape, and dimensionality. We introduce a generalized gauge transformation that allows us to express the diamagnetic coefficient in terms of two characterizations of the size of an exciton, one involving confinement and the other involving the Coulomb interaction. Calculations of the diamagnetic coefficient are given for quantum well, wire, and dot geometries. [S0163-1829(98)00416-0]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Walck, SN (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 15 TC 101 Z9 101 U1 3 U2 13 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 APR 15 PY 1998 VL 57 IS 15 BP 9088 EP 9096 DI 10.1103/PhysRevB.57.9088 PG 9 WC Physics, Condensed Matter SC Physics GA ZJ480 UT WOS:000073219900057 ER PT J AU Gutbrod, T Bayer, M Forchel, A Reithmaier, JP REinecke, TL Rudin, S Knipp, PA AF Gutbrod, T Bayer, M Forchel, A Reithmaier, JP REinecke, TL Rudin, S Knipp, PA TI Weak and strong coupling of photons and excitons in photonic dots SO PHYSICAL REVIEW B LA English DT Article ID INHIBITED SPONTANEOUS EMISSION; MICROCAVITY STRUCTURES; QUANTUM MICROCAVITY; CAVITY; WELLS; FIELD; ATOM AB The weak- and strong-coupling regimes of photons and excitons in photonic dots are studied by photoluminescence spectroscopy. Because of the three-dimensional confinement, the optical mode spectrum is split into a set of discrete states in these structures. The energies of the photon states are studied as a function of the dot size and shape. Further, we investigate the formation of cavity polaritons in photonic dots. The Rabi splitting between the polariton branches is found to depend on the lateral size of the dots and on the photon mode. These dependences are related by calculations to changes of the exciton-photon coupling resulting from photon confinement. [S0163-1829(98)00916-3]. C1 Univ Wurzburg, D-97074 Wurzburg, Germany. USN, Res Lab, Washington, DC 20375 USA. USA, Res Lab, Adelphi, MD 20856 USA. Christopher Newport Univ, Newport News, VA 23606 USA. RP Gutbrod, T (reprint author), Univ Wurzburg, Am Hubland, D-97074 Wurzburg, Germany. RI Reithmaier, Johann/G-8171-2012; OI Reithmaier, Johann/0000-0002-1974-8292; Forchel, Alfred/0000-0002-9377-9935 NR 21 TC 81 Z9 84 U1 2 U2 9 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 APR 15 PY 1998 VL 57 IS 16 BP 9950 EP 9956 DI 10.1103/PhysRevB.57.9950 PG 7 WC Physics, Condensed Matter SC Physics GA ZJ381 UT WOS:000073209000077 ER PT J AU Kajzar, F Okada-Shudo, Y Meritt, C Kafafi, Z AF Kajzar, F Okada-Shudo, Y Meritt, C Kafafi, Z TI Second- and third-order nonlinear optical properties of multilayer and composite C-60-based thin films SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT 5th International Seminar on Highly Conducting Organic Materials for Molecular Electronics CY JUN 08-12, 1997 CL PUSZCZYKOWO, POLAND DE fullerenes; optical properties; films ID 3RD-HARMONIC GENERATION; C-60; C-70; SUSCEPTIBILITY; C60; BUCKMINSTERFULLERENE; DISPERSION AB The nonlinear optical properties of C-60-based composites and multilayered charge-transfer structures with 5,10,15, 20-tetraphenyl-21H,23H-porphine (TPP) and 5,6,11,12-tetraphenylnaphthacene (rubrene) (TPN) acting as electron donors are studied by transverse optical second- and third-harmonic generation. The results are compared with those obtained on pristine and vacuum-photolyzed C-60 thin films. Second-harmonic generation (SHG) is observed from composite films containing C-60 molecules. A significant enhancement in SHG signal is observed in the multilayered structures. This result is interpreted in terms of a ground state permanent electron transfer from the electron-donating molecules to C-60. The third-harmonic generation experiments show an enhancement of the cubic susceptibility from vacuum-photolyzed C-60 thin films. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Ctr Etud Saclay, DEIN SPE GCO, LETI Technol Avancees, CEA, F-91191 Gif Sur Yvette, France. USN, Res Lab, Washington, DC 20375 USA. RP Okada-Shudo, Y (reprint author), Ctr Etud Saclay, DEIN SPE GCO, LETI Technol Avancees, CEA, F-91191 Gif Sur Yvette, France. NR 34 TC 24 Z9 24 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD APR 15 PY 1998 VL 94 IS 1 BP 91 EP 98 DI 10.1016/S0379-6779(97)04151-9 PG 8 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA ZM144 UT WOS:000073509100022 ER PT J AU Bramham, CR Southard, T Ahlers, ST Sarvey, JM AF Bramham, CR Southard, T Ahlers, ST Sarvey, JM TI Acute cold stress leading to elevated corticosterone neither enhances synaptic efficacy nor impairs LTP in the dentate gyrus of freely moving rats SO BRAIN RESEARCH LA English DT Article DE synaptic plasticity; stress; memory; glucocorticoid; hippocampus; long-term potentiation; corticosterone ID LONG-TERM POTENTIATION; PRIMED BURST POTENTIATION; TO-SAMPLE PERFORMANCE; GLUCOCORTICOID RECEPTORS; HIPPOCAMPAL SLICES; SPATIAL MEMORY; BEHAVING RATS; BRAIN; PLASTICITY; ACTIVATION AB Exposure to stress has previously been found to impair long-term potentiation (LTP) in the hippocampus. Exposure to Stress has also been proposed to induce an LTP-like effect. We examined the effect of acute cold stress on synaptic transmission, neuronal excitability, and LTP induction in the medial perforant path-granule cell synapse of freely moving rats. After obtaining baseline recordings of evoked field potentials at room temperature (23 degrees C), rats were transferred to an environmental cage maintained at 4 degrees C (cold group) or 23 degrees C (control group) and, 90 min later, high-frequency stimulation (HFS) was applied to the medial perforant path. Serum corticosterone measured in trunk blood from rats without implanted electrodes was significantly elevated in cold exposed (28.7 mu g/dl) rats relative to control (6.6 mu g/dl). Despite increased corticosterone levels indicative of stress activation, cold exposed rats exhibited LTP of the fEPSP slope and population spike of similar magnitude and time course as controls. In addition, there was no stress-specific effect on the fEPSP slope or population spike and no effect on paired-pulse plasticity. Surprisingly, despite extensive cage acclimation, transferring rats to the environmental cage was associated with a reduction in population spike amplitude and an enhancement in paired-pulse facilitation. The results show that acute cold stress leading to elevated serum corticosterone levels neither induces LTP-like increases in synaptic efficacy nor impairs tetanus-evoked LTP in the dentate gyrus of freely moving rats. Thus, impaired working memory during cold stress is not due to an inability of perforant path synapses to express LTP. (C) 1998 Elsevier Science B.V. C1 Uniformed Serv Univ Hlth Sci, Dept Pharmacol, Bethesda, MD 20814 USA. USN, Inst Med Res, Thermal Stress Adaptat Program, Bethesda, MD 20889 USA. RP Uniformed Serv Univ Hlth Sci, Dept Pharmacol, 4301 Jones Bridge Rd, Bethesda, MD 20814 USA. EM sarvey@usuhsb.usuhs.mil RI yu, yan/C-2322-2012; OI Bramham, Clive/0000-0001-5958-7115 FU NINDS NIH HHS [NS23865] NR 54 TC 36 Z9 42 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0006-8993 EI 1872-6240 J9 BRAIN RES JI Brain Res. PD APR 13 PY 1998 VL 789 IS 2 BP 245 EP 255 DI 10.1016/S0006-8993(97)01265-1 PG 11 WC Neurosciences SC Neurosciences & Neurology GA ZM685 UT WOS:000073565600008 PM 9573376 ER PT J AU Lehmberg, RH Pawley, CJ Schmitt, AJ AF Lehmberg, RH Pawley, CJ Schmitt, AJ TI Comment on "Measurements of Rayleigh-Taylor growth rate of planar targets irradiated directly by partially coherent light" SO PHYSICAL REVIEW LETTERS LA English DT Article C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Lehmberg, RH (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 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 APR 13 PY 1998 VL 80 IS 15 BP 3414 EP 3414 DI 10.1103/PhysRevLett.80.3414 PG 1 WC Physics, Multidisciplinary SC Physics GA ZG567 UT WOS:000073016600065 ER PT J AU Shier, LM Fischer, J AF Shier, LM Fischer, J TI Stellar kinematics of merging galaxies: Clues to the origins of elliptical galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, elliptical and lenticular, cD; galaxies, interactions; galaxies, kinematics and dynamics; galaxies, photometry ID LUMINOUS INFRARED GALAXIES; MERGER REMNANTS; MOLECULAR GAS; ULTRALUMINOUS GALAXIES; VELOCITY DISPERSION; STANDARD STARS; MICRONS; ARP-220 AB There is significant evidence suggesting that mergers of galaxies produce elliptical galaxies. To determine whether the known kinematic properties of elliptical galaxies are consistent with those of their suggested progenitors, we have examined the stellar velocity dispersion in 11 nuclear regions within starbursting infrared-luminous galaxies. All of these galaxies are in some stage of merging. The new data are presented and statistically analyzed in combination with data from the literature. We find that the kinematic and photometric properties of these galaxies suggest that they are the progenitors of low-luminosity (L < L*) elliptical galaxies. Dissipative collapse of gas followed by star formation is apparently not producing a core of high-density high-velocity dispersion stars like those found in very bright elliptical galaxies. We suggest that only the ultraluminous infrared galaxies can possibly produce L* ellipticals. We further present the results of population synthesis models that show that intermediate-age stellar populations should contribute significantly to the light of merger remnants even after the morphological signs of merging have vanished. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Shier, LM (reprint author), Raytheon Syst Co, El Segundo, CA 90245 USA. NR 38 TC 50 Z9 50 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 APR 10 PY 1998 VL 497 IS 1 BP 163 EP 167 DI 10.1086/305434 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZG883 UT WOS:000073049600014 ER PT J AU Wehrle, AE Pian, E Urry, CM Maraschi, L McHardy, IM Lawson, AJ Ghisellini, G Hartman, RC Madejski, GM Makino, F Marscher, AP Wagner, SJ Webb, JR Aldering, GS Aller, MF Aller, HD Backman, DE Balonek, TJ Boltwood, P Bonnell, J Caplinger, J Celotti, A Collmar, W Dalton, J Drucker, A Falomo, R Fichtel, CE Freudling, W Gear, WK Gonzalez-Perez, N Hall, P Inoue, H Johnson, WN Kazanas, D Kidger, MR Kii, T Kollgaard, RI Kondo, Y Kurfess, J Lin, YC McCollum, B McNaron-Brown, K Nagase, F Nair, AD Penton, S Pesce, JE Pohl, M Raiteri, CH Renda, M Robson, EI Sambruna, RM Schirmer, AF Shrader, C Sikora, M Sillanpaa, A Smith, PS Stevens, JA Stocke, J Takalo, LO Terasranta, H Thompson, DJ Thompson, R Tornikoski, M Tosti, G Treves, A Turcotte, P Unwin, SC Valtaoja, E Villata, M Xu, W Yamashita, A Zook, A AF Wehrle, AE Pian, E Urry, CM Maraschi, L McHardy, IM Lawson, AJ Ghisellini, G Hartman, RC Madejski, GM Makino, F Marscher, AP Wagner, SJ Webb, JR Aldering, GS Aller, MF Aller, HD Backman, DE Balonek, TJ Boltwood, P Bonnell, J Caplinger, J Celotti, A Collmar, W Dalton, J Drucker, A Falomo, R Fichtel, CE Freudling, W Gear, WK Gonzalez-Perez, N Hall, P Inoue, H Johnson, WN Kazanas, D Kidger, MR Kii, T Kollgaard, RI Kondo, Y Kurfess, J Lin, YC McCollum, B McNaron-Brown, K Nagase, F Nair, AD Penton, S Pesce, JE Pohl, M Raiteri, CH Renda, M Robson, EI Sambruna, RM Schirmer, AF Shrader, C Sikora, M Sillanpaa, A Smith, PS Stevens, JA Stocke, J Takalo, LO Terasranta, H Thompson, DJ Thompson, R Tornikoski, M Tosti, G Treves, A Turcotte, P Unwin, SC Valtaoja, E Villata, M Xu, W Yamashita, A Zook, A TI Multiwavelength observations of a dramatic high-energy flare in the blazar 3C 279 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, photometry; gamma rays, observations; quasars, individual (3C 279); radiation mechanisms, nonthermal ID ACTIVE GALACTIC NUCLEI; RADIO-SOURCES; RAY-EMISSION; 3C-279; CALIBRATION; VARIABILITY; PHOTOMETRY; RADIATION; SYSTEM; JET AB The blazar 3C 279, one of the brightest identified extragalactic objects in the gamma-ray sky, underwent a large (factor of similar to 10 in amplitude) flare in gamma-rays toward the end of a 3 week pointing by Compton Gamma Ray Observatory (CGRO), in 1996 January-February. The flare peak represents the highest gamma-ray intensity ever recorded for this object. During the high state, extremely rapid gamma-ray variability was seen, including an increase of a factor of 2.6 in similar to 8 hr, which strengthens the case for relativistic beaming. Coordinated multifrequency observations were carried out with Rossi X-Ray Timing Explorer (RXTE), Advanced Satellite for Cosmology and Astrophysics (ASCA; ol, Astro-D), Roentgen Satellite (ROSAT), and Intel national Ultraviolet Explorer (IUE) and from many ground-based observatories, covering most accessible wavelengths. The well-sampled, simultaneous RXTE light curve shows an outburst of lower amplitude (factor of similar or equal to 3) well correlated with the gamma-ray flare without any lag larger than the temporal resolution of similar to 1 day. The optical-UV light curves, which are not well sampled during the high-energy flare, exhibit more modest variations (factor of similar to 2) and a lower degree of correlation. The flux at millimetric wavelengths was near a historical maximum during the gamma-ray flare peak, and there is a suggestion of a correlated decay. We present simultaneous spectral energy distributions of 3C 279 prior to and near to the flare peak. The gamma-rays vary by more than the square of the observed IR-optical flux change, which poses some problems for specific blazar emission models. The synchrotron self-Compton (SSC) model would require that the largest synchrotron variability occurred in the mostly unobserved submillimeter/far-infrared region. Alternatively, a large variation in the external photon held could occur over a timescale of a few days. This occurs naturally in the "mirror" model, wherein the flaring region in the jet photoionizes nearby broad emission line clouds, which, in turn, provide soft external photons that are Comptonized to gamma-ray energies. C1 Infrared Proc Anal Ctr, Jet Prop Lab, Pasadena, CA 91125 USA. CALTECH, Pasadena, CA 91125 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CNR, ITESRE, I-40129 Bologna, Italy. Osservatorio Astron Brera, I-20121 Milan, Italy. Univ Southampton, Dept Phys, Southampton SO9 5NH, Hants, England. Osservatorio Astron Brera, I-22055 Merate, Lecco, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Inst Space & Astronaut Sci, Kanagawa 229, Japan. Boston Univ, Dept Astron, Boston, MA 02215 USA. Landessternwarte, Heidelberg Konigsstuhl, D-69117 Heidelberg, Germany. Florida Int Univ, Dept Phys, Miami, FL 33199 USA. NOAO, KPNO, SARA Observ, Tucson, AZ 85726 USA. Univ Minnesota, Dept Astron, Minneapolis, MN 55455 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Franklin & Marshall Coll, Dept Phys & Astron, Lancaster, PA 17604 USA. Colgate Univ, Dept Phys & Astron, Hamilton, NY 13346 USA. SISSA, ISAS, I-34014 Trieste, Italy. Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Osservatorio Astron Padova, I-35122 Padua, Italy. Space Telescope European Coordinating Facil, D-85748 Garching, Germany. Univ Cent Lancashire, Ctr Astrophys, Preston PR1 2HE, Lancs, England. Inst Astrofis Canarias, E-38200 La Laguna, Tenerife, Spain. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. USN, Res Lab, Washington, DC 20375 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Stanford Univ, WW Hansen Labs Phys, Stanford, CA 94305 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Univ Florida, Dept Astron, Gainesville, FL 32601 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. Penn State Univ, Dept Astron, Davey Lab 525, University Pk, PA 16802 USA. Osservatorio Astron Torino, I-10025 Pino Torinese, Italy. Joint Astron Ctr, Hilo, HI 96720 USA. Polish Acad Sci, Copernicus Astron Ctr, Warsaw, Poland. Tuorla Observ, Tuorla 21500, Piikkio, Finland. Natl Opt Astron Observ, KPNO, Tucson, AZ 85726 USA. Metsahovi Radio Res Stn, Kylmala 02540, Finland. Univ Perugia, Osservatorio Astron, I-06100 Perugia, Italy. Univ Milan, Dept Phys, I-22100 Como, Italy. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Pomona Coll, Dept Phys & Astron, Claremont, CA 91711 USA. RP Wehrle, AE (reprint author), Infrared Proc Anal Ctr, Jet Prop Lab, MC 100-22, Pasadena, CA 91125 USA. RI Thompson, David/D-2939-2012; Tosti, Gino/E-9976-2013; Urry, Claudia/G-7381-2011; Johnson, Neil/G-3309-2014; OI Thompson, David/0000-0001-5217-9135; Urry, Claudia/0000-0002-0745-9792; Villata, Massimo/0000-0003-1743-6946; Falomo, Renato/0000-0003-4137-6541; Raiteri, Claudia Maria/0000-0003-1784-2784; Pian, Elena/0000-0001-8646-4858 NR 39 TC 203 Z9 208 U1 1 U2 3 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 APR 10 PY 1998 VL 497 IS 1 BP 178 EP 187 DI 10.1086/305461 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZG883 UT WOS:000073049600016 ER PT J AU Lazio, TJW Cordes, JM AF Lazio, TJW Cordes, JM TI The radial extent and warp of the ionized galactic disk. II. A likelihood analysis of radio-wave scattering toward the anticenter SO ASTROPHYSICAL JOURNAL LA English DT Article DE dust, extinction; Galaxy, structure; H Pi regions; scattering; surveys; turbulence ID ANGULAR BROADENING MEASUREMENTS; H-ALPHA EMISSION; INTERSTELLAR SCATTERING; VLBI OBSERVATIONS; FREE-ELECTRONS; OUTER-GALAXY; STELLAR DISK; SOLAR CIRCLE; IRAS SOURCES; PULSARS AB We use radio-wave scattering data for extragalactic sources and pulsars to constrain the distribution of ionized gas in the outer Galaxy. Like previous models, our model for the H II disk includes parameters for the radial scale length and scale height of the ionized gas. In addition, we have used the known H I distribution in the outer Galaxy in constructing our model, and we allow the H II disk to warp and flare. We also include the Perseus arm in our model. We use a likelihood analysis of 18 anticenter sources with measured scattering observables: 11 extragalactic sources and 7 pulsars. We find that the strength of scattering in the Perseus arm is no more than 60% of the level contributed by spiral arms in the inner Galaxy and is equivalent to a scattering diameter of 1.5 mas at 1 GHz. Our analysis favors an unwarped, nonflaring disk with a scale height of 1 kpc, though this may reflect the nonuniform and coarse coverage of the anticenter provided by the available data. One extragalactic source has a size a factor of 2 smaller than predicted by our model, possibly indicating the existence of holes in the scattering material. The lack of a warp in the scattering material indicates that VLBI observations near 1 GHz with an orbiting station having baseline lengths of a few Earth diameters will not be affected by interstellar scattering at moderate Galactic latitudes, \b\ approximate to 15 degrees. The radial scale length is 15-20 kpc, but the data cannot distinguish between a gradual decrease in the electron density and a truncated distribution. We favor a truncated one because we associate the scattering with massive star formation, which is also truncated near 20 kpc. A radial extent of 20 kpc is also comparable to the radial extent of Ha emission observed for nearby spiral galaxies. We find that the distribution of electron density turbulence must decrease more rapidly with Galactocentric distance than does the distribution of hydrogen. Alternate ionizing and turbulent agents-the intergalactic ionizing flux and the passage of satellite galaxies through the disk-are unlikely to contribute significant amounts to scattering in the anticenter. We cannot exclude the possibility that a largely ionized but quiescent disk, similar to that inferred for some Ly alpha absorbers, extends to greater than or equal to 100 kpc. C1 Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Cornell Univ, Natl Astron & Ionosphere Ctr, Ithaca, NY 14853 USA. RP Lazio, TJW (reprint author), NRL, Code 7210, Washington, DC 20375 USA. NR 62 TC 12 Z9 12 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 APR 10 PY 1998 VL 497 IS 1 BP 238 EP 252 DI 10.1086/305448 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZG883 UT WOS:000073049600020 ER PT J AU Strickman, MS Tavani, M Coe, MJ Steele, IA Fabregat, J Marti, J Paredes, JM Ray, PS AF Strickman, MS Tavani, M Coe, MJ Steele, IA Fabregat, J Marti, J Paredes, JM Ray, PS TI A multiwavelength investigation of the relationship between 2CG 135+1 and LSI+61 degrees 303 SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries, close; gamma rays, observations; stars, emission-line, Be; stars, individual (LSI+61 degrees 303); X-rays, stars ID STAR LSI +61-DEGREES-303; GAMMA-RAY SOURCES; COS-B; RADIO; OUTBURST; SPECTRA AB We present the results of a multiwavelength monitoring campaign targeting the gamma-ray source 2CG 135+1 in an attempt to confirm the association of this object with the radio/Be/X-ray binary system LSI +61 degrees 303. The campaign included simultaneous radio, optical, infrared, and hard X-ray/gamma-ray observations carried out with a variety of instruments, covering (not continuously) almost three binary cycles of LSI +61 degrees 303 during the period 1994 April-July. Three separate OSSE observations of the gamma-ray source were carried out, covering different phases of the radio light curve. Hard X-ray/gamma-ray emission was detected from the direction of 2CG 135 + 1 during the first of these OSSE observations. The signal-to-noise ratio of the OSSE observations was insufficient to establish a spectral or intensity correlation of the high-energy emission with simultaneous radio, optical, and infrared emission of LSI +61 degrees 303. We briefly discuss the theoretical implications of our observations. C1 USN, Res Lab, Washington, DC 20375 USA. Columbia Univ, Astrophys Lab, New York, NY 10027 USA. Univ Southampton, Dept Phys & Astron, Southampton SO17 1BJ, Hants, England. Liverpool John Moores Univ, Astrophys Grp, Liverpool L3 3AF, Merseyside, England. Univ Valencia, Dept Astron, E-46100 Burjassot, Spain. Ctr Etud Saclay, CEA, DSM, DAPNIA,Serv Astrophys, F-91191 Gif Sur Yvette, France. Univ Barcelona, Dept Astron & Meteorol, E-08028 Barcelona, Spain. RP Strickman, MS (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM strickman@osse.nrl.navy.mil; tavani@astro.columbia.edu; mjc@astro.soton.ac.uk; ias@staru1.livjm.ac.uk; fabregat@evalvx.ific.uv.es; josepmp@mizar.am.ub.es; paulr@rira.nrl.navy.mil RI Fabregat, Juan/F-9066-2016 OI Fabregat, Juan/0000-0002-5986-9347 NR 45 TC 33 Z9 33 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 1998 VL 497 IS 1 BP 419 EP 430 DI 10.1086/305446 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZG883 UT WOS:000073049600033 ER PT J AU Gammon, D AF Gammon, D TI The evidence of small things SO SCIENCE LA English DT Article ID QUANTUM DOTS; PHOTOLUMINESCENCE; SPECTROSCOPY; ISLANDS; GROWTH; GAAS C1 USN, Res Lab, Washington, DC 20375 USA. RP Gammon, D (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 24 TC 3 Z9 3 U1 1 U2 5 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD APR 10 PY 1998 VL 280 IS 5361 BP 225 EP 225 DI 10.1126/science.280.5361.225 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZH195 UT WOS:000073082400034 ER PT J AU Garland, NL Nelson, HH AF Garland, NL Nelson, HH TI Laser-induced decomposition of TNAZ SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID THERMAL-DECOMPOSITION; 1,3,3-TRINITROAZETIDINE; PYROLYSIS AB The initial decomposition products of 1,3,3-trinitroazetidine (TNAZ) are characterized using time-of-flight mass spectrometry. To induce thermal decomposition, solid samples of TNAZ are irradiated with 248 nm laser pulses. Products released to the gas phase are ionized by a pulse of 118 nm light, and the ions are detected using a time-of-flight mass spectrometer. Neutral time-of-arrival scans are used to determine the translational temperature and the relative yields of the products. The translational temperature is found to depend linearly on the decomposition laser fluence, consistent with a photothermal decomposition mechanism. Analysis of the temperature dependence of the relative product yields shows that two reactions are important in the initial decomposition of TNAZ: unimolecular nitro-nitrite rearrangement followed by loss of NO and a bimolecular reaction generating nitrosodinitroazetidine (NDNAZ). Loss of NO2 appears to be an early, but not initial, decomposition step. Experiments with isotopically labeled TNAZ show that the nitro-nitrite rearrangement occurs on the nitramine group and that NO is lost from both the nitroalkyl and nitramine groups. NDNAZ is generated by replacement of the leaving nitramine nitro group by NO. C1 USN, Div Chem, Res Lab, Washington, DC 20375 USA. RP Garland, NL (reprint author), USN, Div Chem, Res Lab, Code 6111, Washington, DC 20375 USA. NR 21 TC 15 Z9 15 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 9 PY 1998 VL 102 IS 15 BP 2663 EP 2667 DI 10.1021/jp980201d PG 5 WC Chemistry, Physical SC Chemistry GA ZJ961 UT WOS:000073271100009 ER PT J AU Baum, K Baum, JC Ho, T AF Baum, K Baum, JC Ho, T TI Side-loop polymers based on the hydrosilylation of polybutadiene SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article AB Hydrosilylation of hydride-terminated poly(dimethylsiloxane) with polybutadiene in dilute solution yielded polysiloxane side-loops on a hydrocarbon base, a novel polymer architecture. When the ratio of silane to olefin was increased, the inherent viscosity of solutions dropped drastically, and polymer properties changed from tough rubbers to tacky materials. The results are rationalized on the basis of diminishing availability of olefin sites as the reaction proceeds. When one end of a difunctional silane attaches to an olefin site and no other olefin sites are available nearby, molecular motion eventually brings a remote olefin site in the molecule into proximity. Hydrosilylation then results in permanent ring folding. Subsequent hydrosilylations can then result in a dendrimer-like globular molecule. Contact angle measurements of side-loop adducts show temporal stability, indicating that the tendency of poly(dimethylsiloxane) side chains to migrate to or away from the surface, depending on the medium, is circumvented by anchoring both ends. C1 Fluorochem Inc, Azusa, CA 91702 USA. USN, Res Lab, Washington, DC 20375 USA. RP Baum, K (reprint author), Fluorochem Inc, 680 S Ayon Ave, Azusa, CA 91702 USA. NR 29 TC 10 Z9 10 U1 1 U2 8 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 APR 8 PY 1998 VL 120 IS 13 BP 2993 EP 2996 DI 10.1021/ja973666a PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA ZH106 UT WOS:000073072700001 ER PT J AU Navidi, W Murphy, WS Hereman, W AF Navidi, W Murphy, WS Hereman, W TI Statistical methods in surveying by trilateration SO COMPUTATIONAL STATISTICS & DATA ANALYSIS LA English DT Article DE iteratively reweighted least squares; quasi-likelihood; Monte-Carlo simulation; trilateration; computerized surveying; global positioning system (GPS) AB Trilateration techniques use distance measurements to survey the spatial coordinates of unknown positions. In practice, distances are measured with error, and statistical methods can quantify the uncertainty in the estimate of the unknown location. Three methods for estimating the three-dimensional position of a point via trilateration are presented: a linear least-squares estimator, an iteratively reweighted least-squares estimator, and a non-linear least-squares technique. In general, the non-linear least-squares technique performs best, but in some situations a linear estimator could in theory be constructed that would outperform it. By eliminating the need to measure angles, trilateration facilitates the implementation of fully automated real-time positioning systems similar to the global positioning system (GPS). The methods presented in this paper are tested in the context of a realistic positioning problem that was posed by the Thunder Basin Coal Company in Wright, Wyoming. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Colorado Sch Mines, Dept Math & Comp Sci, Golden, CO 80401 USA. USN, Postgrad Sch, USA, TRADOC Anal Ctr Monterey, Monterey, CA 93943 USA. RI Hereman, Willy/E-7783-2010 OI Hereman, Willy/0000-0001-7997-6601 NR 15 TC 28 Z9 28 U1 1 U2 6 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 APR 3 PY 1998 VL 27 IS 2 BP 209 EP 227 DI 10.1016/S0167-9473(97)00053-4 PG 19 WC Computer Science, Interdisciplinary Applications; Statistics & Probability SC Computer Science; Mathematics GA ZK160 UT WOS:000073291400006 ER PT J AU Anderson, ML Morris, CA Merzbacher, CI Rolison, DR AF Anderson, ML Morris, CA Merzbacher, CI Rolison, DR TI Colloidal Au aerogels: Preparation, properties, and characterization. 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 APR 2 PY 1998 VL 215 MA 309-COLL BP U501 EP U501 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401590 ER PT J AU Brady, RF AF Brady, RF TI Modern organic surface coatings for the marine industry. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Div Chem, 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 APR 2 PY 1998 VL 215 MA 192-PMSE BP U339 EP U339 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414501089 ER PT J AU Brady, RF Bonafede, SJ AF Brady, RF Bonafede, SJ TI Crystallinity differences in polypropylene arising from processing variables. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Div Chem, 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 APR 2 PY 1998 VL 215 MA 126-PMSE BP U318 EP U318 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414501024 ER PT J AU Brady, RF Bonafede, SJ AF Brady, RF Bonafede, SJ TI Effects of processing conditions on the surface properties of polypropylene. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Div Chem, 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 APR 2 PY 1998 VL 215 MA 125-PMSE BP U318 EP U318 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414501023 ER PT J AU Brandow, SL Snow, ES Campbell, PM AF Brandow, SL Snow, ES Campbell, PM TI Metal pattern fabrication using a conducting tip atomic force microscope. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Washington, DC 20375 USA. Shipley Co Inc, Marlboro, MA 01752 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 APR 2 PY 1998 VL 215 MA 247-PHYS BP U213 EP U213 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414500723 ER PT J AU Browning, VM Skelton, EF Qadri, SB Osofsky, MS AF Browning, VM Skelton, EF Qadri, SB Osofsky, MS TI Structural inhomogeneities observed in superconducting YBa2Cu3O7-d crystals with optimum transport properties SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Washington, DC 20375 USA. RI Osofsky, Michael/A-1050-2010 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 APR 2 PY 1998 VL 215 MA 023-IEC BP U661 EP U661 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414402099 ER PT J AU Campbell, ML AF Campbell, ML TI Kinetic study of the reaction of Zr(a(3)F(2)) with O-2, CO2, N2O, NO, H2O and SO2 from 296 to 498 K. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 2 PY 1998 VL 215 MA 314-PHYS BP U233 EP U233 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414500790 ER PT J AU Fallis, KA Higa, KT AF Fallis, KA Higa, KT TI Synthesis of novel aluminum-tellurium compounds and the investigation of responsible reaction mechanisms. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Air Warfare Ctr, Weap Div, Chem & Mat Branch,Res & Technol Grp, 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 APR 2 PY 1998 VL 215 MA 301-INOR BP U788 EP U788 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414402529 ER PT J AU Ferrante, RF Moore, MH Nuth, JA AF Ferrante, RF Moore, MH Nuth, JA TI Surface effects and the low temperature crystallization of ices SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. NASA, Astrochem Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. 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 APR 2 PY 1998 VL 215 MA 139-PHYS BP U183 EP U183 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414500616 ER PT J AU Grabowski, KS Knies, DL DeTurck, TM Treacy, DJ Hubler, GK AF Grabowski, KS Knies, DL DeTurck, TM Treacy, DJ Hubler, GK TI Initial results from the new accelerator mass spectrometer at the Naval Research Laboratory. 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 APR 2 PY 1998 VL 215 MA 131-NUCL BP U966 EP U966 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414403119 ER PT J AU Houser, EJ Keller, TM AF Houser, EJ Keller, TM TI Novel linear 1,4-phenylene siloxyl/silylene diacetylene polymers and their conversion to thermosets and ceramics. 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. 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 APR 2 PY 1998 VL 215 MA 259-INOR BP U776 EP U777 PN 1 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414402487 ER PT J AU Johnston, EE Gatenholm, P Bullock, SE Wynne, KJ AF Johnston, EE Gatenholm, P Bullock, SE Wynne, KJ TI Polydimethylsiloxane networks crosslinked with fluoroalkyl (triethoxy)silane: Novel surface microstructures. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Mat Chem Br, Washington, DC 20375 USA. Virginia Polytech Inst & State Univ, Dept Chem, Blacksburg, VA 24061 USA. Chalmers Univ Technol, S-41296 Gothenburg, Sweden. George Mason Univ, Arlington, VA 22030 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 APR 2 PY 1998 VL 215 MA 314-POLY BP U436 EP U436 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414501425 ER PT J AU Karle, IL AF Karle, IL TI Conformations and folding of natural and "designer" peptides SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 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 APR 2 PY 1998 VL 215 MA 106-MEDI BP U891 EP U891 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414402881 ER PT J AU Kowalewski, T Bullock, S Pike, JD AF Kowalewski, T Bullock, S Pike, JD TI Atomic force microscopy of surface and subsurface regions of silicone-based materials. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Washington Univ, Dept Chem, St Louis, MO 63130 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 APR 2 PY 1998 VL 215 MA 370-POLY BP U451 EP U451 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414501481 ER PT J AU Lomax, JF Dillner, DK AF Lomax, JF Dillner, DK TI Web forms for general chemistry lab SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 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 APR 2 PY 1998 VL 215 MA 646-CHED BP U361 EP U361 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401163 ER PT J AU Long, JW Swider, KE Merzbacher, CI Rolison, DR AF Long, JW Swider, KE Merzbacher, CI Rolison, DR TI Ruthenium dioxide-impregnated aerogels as high surface area electrode materials. 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 APR 2 PY 1998 VL 215 MA 106-COLL BP U434 EP U434 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401392 ER PT J AU Malhotra, R McMillen, DF Hardy, DR Beal, EJ Morris, RE Black, BH AF Malhotra, R McMillen, DF Hardy, DR Beal, EJ Morris, RE Black, BH TI Effect of C-60 on oxidative stability of fuels. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 SRI Int, Menlo Park, CA 94025 USA. USN, Res Lab, Washington, DC 20036 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 2 PY 1998 VL 215 MA 011-FUEL BP U595 EP U596 PN 1 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401905 ER PT J AU Markowitz, MA Dunn, DN Chow, GM AF Markowitz, MA Dunn, DN Chow, GM TI The influence of membrane charge on gold nanoparticle synthesis via surfactant membranes. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Lab Mol Interfacial Interact, 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 APR 2 PY 1998 VL 215 MA 180-COLL BP U456 EP U456 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401466 ER PT J AU Markowitz, MA Kurihara, L Schoen, PE Zabetakis, D Turner, DC Gaber, BP AF Markowitz, MA Kurihara, L Schoen, PE Zabetakis, D Turner, DC Gaber, BP TI Functionalized silica gel particles for molecular imprinting. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Lab Mol Interfacial Interact, 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 APR 2 PY 1998 VL 215 MA 179-COLL BP U455 EP U455 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401465 ER PT J AU McClean, RE AF McClean, RE TI Depletion kinetics of Ni(a(3)F(J), a(3)D(J)) by SO2. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 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 APR 2 PY 1998 VL 215 MA 315-PHYS BP U233 EP U233 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414500791 ER PT J AU Mehl, PM AF Mehl, PM TI Glass transition in the system Melibiose-Bovine Serum Albumin-Water. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Med Res Inst, NNMC,Cryobiophys Sect, Transfus & Cryopreservat Res Program, Bethesda, MD 20889 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 APR 2 PY 1998 VL 215 MA 106-PHYS BP U174 EP U174 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414500583 ER PT J AU Morris, RE AF Morris, RE TI Reaction kinetics in supercritical fluids. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Technol Ctr Safety & Survivabil, Washington, DC 20375 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 2 PY 1998 VL 215 MA 039-FUEL BP U603 EP U604 PN 1 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401933 ER PT J AU Mushrush, GW Beal, EJ Hardy, DR Stalick, WM Basu, S Cummings, J AF Mushrush, GW Beal, EJ Hardy, DR Stalick, WM Basu, S Cummings, J TI Jet fuel system icing inhibitors: Synthesis and stability. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 George Mason Univ, Fairfax, VA 22030 USA. USN, Technol Ctr Safety & Survivabil, Washington, DC 20375 USA. Innovat Sci Solut Inc, Dayton, OH 45440 USA. John Cummings Naval Air Warfare Ctr, Trenton, NJ 08628 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 APR 2 PY 1998 VL 215 MA 023-FUEL BP U599 EP U599 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401917 ER PT J AU Pande, SG AF Pande, SG TI Thermal stability measurement devices revisited: Gravimetric JFTOT versus simulated test rig. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Washington, DC 20375 USA. Geocenters Inc, Lanham, MD 20706 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 APR 2 PY 1998 VL 215 MA 043-FUEL BP U605 EP U605 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401937 ER PT J AU Purdy, AP AF Purdy, AP TI Ammonothermal synthesis and growth of cubic gallium nitride 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 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 2 PY 1998 VL 215 MA 219-INOR BP U766 EP U766 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414402447 ER PT J AU Rolison, DR AF Rolison, DR TI Dispersed nanocrystallite electrocatalysts: How to divorce the reactor electrode from the catalyzed electron transfer reaction. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Washington, DC 20375 USA. Villanova Univ, Dept Chem, Villanova, PA 18015 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 APR 2 PY 1998 VL 215 MA 203-COLL BP U462 EP U462 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401489 ER PT J AU Seligman, PF Valkirs, AO Johnson, HD AF Seligman, PF Valkirs, AO Johnson, HD TI The effect of legislation and regulation on tributyltin risk in the marine and estuarine environments of the United States. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Div Environm Sci, San Diego, CA 92152 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 APR 2 PY 1998 VL 215 MA 075-ENVR BP U589 EP U589 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401892 ER PT J AU Shaffer, RE Cross, JO Rose-Pehrsson, SL Elam, WT AF Shaffer, RE Cross, JO Rose-Pehrsson, SL Elam, WT TI Multivariate analysis of x-ray absorption near-edge spectra: Application to chromium speciation SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Washington, DC 20375 USA. RI Shaffer, Ronald/I-2134-2012 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 APR 2 PY 1998 VL 215 MA 014-ANYL BP U64 EP U64 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414400199 ER PT J AU Urban, JJ Cronin, CW AF Urban, JJ Cronin, CW TI Conformational analysis of the neurotransmitter acetylcholine. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 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 APR 2 PY 1998 VL 215 MA 131-COMP BP U541 EP U541 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414401723 ER PT J AU Yeh, SL Wood, AL Vane, LM AF Yeh, SL Wood, AL Vane, LM TI Integrated demonstration of surfactant-enhanced aquifer remediation (SEAR) with surfactant regeneration and reuse. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Facil Engn Serv Ctr, Port Hueneme, CA 93043 USA. US EPA, Natl Risk Management Res Lab, Ada, OK 74820 USA. US EPA, NRMRL, Cincinnati, OH 45268 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 2 PY 1998 VL 215 MA 059-IEC BP U671 EP U671 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA ZA911 UT WOS:000072414402135 ER PT J AU Zarras, P Stenger-Smith, JD Ostrom, GS Merwin, LH Cameron, DA Reynolds, JR AF Zarras, P Stenger-Smith, JD Ostrom, GS Merwin, LH Cameron, DA Reynolds, JR TI Improved synthesis and physical properties of poly(2,5-bis(N-methyl-N-propylamino)phenylene vinylene)s 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. Univ Florida, Dept Chem, Gainesville, FL 32611 USA. Univ Florida, Ctr Macromol Sci & Engn, Gainesville, FL 32611 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 APR 2 PY 1998 VL 215 MA 014-POLY BP U354 EP U355 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA ZA912 UT WOS:000072414501126 ER PT J AU Miranda, JA Devenport, WJ AF Miranda, JA Devenport, WJ TI Turbulence structure in the spiral wake shed by a lifting wing 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 TIP VORTEX C1 Virginia Polytech Inst & State Univ, Dept Aerosp & Ocean Engn, Blacksburg, VA 24060 USA. RP Miranda, JA (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02847 USA. NR 12 TC 3 Z9 3 U1 1 U2 5 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 APR PY 1998 VL 36 IS 4 BP 658 EP 660 DI 10.2514/2.421 PG 3 WC Engineering, Aerospace SC Engineering GA ZE549 UT WOS:000072804600023 ER PT J AU Symonds, CL AF Symonds, CL TI The battles for Spotsylvania Courthouse and the road to Yellow Tavern, May 7-12, 1864 SO AMERICAN HISTORICAL REVIEW LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Symonds, CL (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER HISTORICAL REVIEW PI WASHINGTON PA 400 A ST SE, WASHINGTON, DC 20003 USA SN 0002-8762 J9 AM HIST REV JI Am. Hist. Rev. PD APR PY 1998 VL 103 IS 2 BP 604 EP 605 DI 10.2307/2649920 PG 2 WC History SC History GA ZH651 UT WOS:000073133400153 ER PT J AU Mills, JN Johnson, JM Ksiazek, TG Ellis, BA Rollin, PE Yates, TL Minn, MO Johnson, MR Campbell, ML Miyashiro, J Patrick, M Zyzak, M Lavender, D Novak, MG Schmidt, K Peters, CJ Childs, JE AF Mills, JN Johnson, JM Ksiazek, TG Ellis, BA Rollin, PE Yates, TL Minn, MO Johnson, MR Campbell, ML Miyashiro, J Patrick, M Zyzak, M Lavender, D Novak, MG Schmidt, K Peters, CJ Childs, JE TI A survey of hantavirus antibody in small-mammal populations in selected United States National Parks SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID GENETIC IDENTIFICATION; VIRUS; RODENTS; INFECTION; ILLNESS; USA AB Hantavirus activity in 39 National Parks in the eastern and central United States was surveyed by testing 1,815 small mammals of 38 species for antibody reactive to Sin Nombre virus. Antibody-positive rodents were found throughout the area sampled, and in most biotic communities. Antibody was detected in 7% of 647 deer mice (Peromyscus maniculatus), 2% of 590 white-footed mice (P. leucopus), 17% of 12 rice rats (Oryzomys palustris), 3% of 31 cotton rats (Sigmodon hispidus), and 33% of 18 western harvest mice (Reithrodontomys megalotis). Antibody was also found in three of six species of voles, and in one of 33 chipmunks (Tamias minimus). Prevalence among Peromyscus was highest in the northeast. Although few cases of hantavirus pulmonary syndrome have been identified from the eastern and central regions, widespread infection in reservoir populations indicates that potential exists for human infection throughout much of the United States. C1 Ctr Dis Control & Prevent, Div Viral & Rickettsial Dis, Atlanta, GA 30333 USA. Natl Pk Serv, Washington, DC 20013 USA. Univ New Mexico, Dept Biol, Museum SW Biol, Albuquerque, NM 87131 USA. USN, Dis Vector Ecol & Control Ctr, Poulsbo, WA USA. Wildlife Vet Resources, Gardiner, MT 59030 USA. Penn State Univ, Altoona, PA 16601 USA. RP Mills, JN (reprint author), Ctr Dis Control & Prevent, Div Viral & Rickettsial Dis, 1600 Clifton Rd, Atlanta, GA 30333 USA. RI Childs, James/B-4002-2012 NR 30 TC 65 Z9 74 U1 0 U2 6 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DR, STE 130, MCLEAN, VA 22101 USA SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD APR PY 1998 VL 58 IS 4 BP 525 EP 532 PG 8 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA ZK139 UT WOS:000073289300023 PM 9574803 ER PT J AU Koch, JA Landen, OL Barbee, TW Celliers, P Da Silva, LB Glendinning, SG Hammel, BA Kalantar, DH Brown, C Seely, J Bennett, GR Hsing, W AF Koch, JA Landen, OL Barbee, TW Celliers, P Da Silva, LB Glendinning, SG Hammel, BA Kalantar, DH Brown, C Seely, J Bennett, GR Hsing, W TI High-energy x-ray microscopy techniques for laser-fusion plasma research at the National Ignition Facility SO APPLIED OPTICS LA English DT Article ID NOVA AB Multi-kilo-eledron-volt x-ray microscopy will be an important laser-produced plasma diagnostic at future megajoule facilities such as the National Ignition Facility (NIF). However, laser energies and plasma characteristics imply that x-ray microscopy will be more challenging at NIF than at existing facilities. We use analytical estimates and numerical ray tracing to investigate several instrumentation options in detail, and we conclude that near-normal-incidence single spherical or toroidal crystals may offer the best general solution for high-energy x-ray microscopy at NIF and similar large facilities. Apertured Kirkpatrick-Baez microscopes using multilayer mirrors may also be good options, particularly for applications requiring one-dimensional imaging over narrow fields of view. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Koch, JA (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-473, Livermore, CA 94550 USA. NR 27 TC 79 Z9 88 U1 0 U2 6 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 APR 1 PY 1998 VL 37 IS 10 BP 1784 EP 1795 DI 10.1364/AO.37.001784 PG 12 WC Optics SC Optics GA ZD695 UT WOS:000072713700012 PM 18273089 ER PT J AU Bermudez, VM Koleske, DD Wickenden, AE AF Bermudez, VM Koleske, DD Wickenden, AE TI The dependence of the structure and electronic properties of wurtzite GaN surfaces on the method of preparation SO APPLIED SURFACE SCIENCE LA English DT Article ID X-RAY PHOTOEMISSION; VAPOR-PHASE EPITAXY; GAN(0001)-(1X1) SURFACE; NATIVE DEFECTS; BUFFER LAYERS; FILMS; GROWTH; HYDROGEN; ALN; SPECTROSCOPY AB The effects of in situ cleaning, thermal and chemical treatments on wurtzite GaN surfaces have been studied using various electron spectroscopies and low energy electron diffraction (LEED). Nitrogen-ion bombardment or deposition of Ga metal, followed by annealing in UHV, yields clean (1 X 1)-ordered surfaces, with the latter giving a somewhat better LEED pattern. Uniform heating during annealing appears important in avoiding facetting. Annealing an 'as-inserted' surface either in UHV or in a flux of NH3 vapor is not completely effective in cleaning, but annealing a clean ion-bombarded surface in NH3 impedes the formation of N vacancies which occurs in UHV. Surface band bending depends on anneal temperature for both as-inserted and ion-bombarded samples, changing by up to 0.7 eV from 300 to 700 degrees C. This is tentatively explained by the accumulation of surface Ga vacancies which act as accepters. Adsorbed H removes a surface state near the valence band maximum but is very sensitive to desorption by impact of similar to 90 eV electrons. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Washington, DC 20375 USA. RP Bermudez, VM (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM bermudez@estd.nrl.navy.mil NR 74 TC 149 Z9 149 U1 0 U2 41 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD APR PY 1998 VL 126 IS 1-2 BP 69 EP 82 DI 10.1016/S0169-4332(97)00582-5 PG 14 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA ZK564 UT WOS:000073337800009 ER PT J AU Chiang, J Mukherjee, R AF Chiang, J Mukherjee, R TI The luminosity function of the EGRET gamma-ray blazars SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, active; galaxies, luminosity function, mass function; gamma rays, observations; quasars, general ID ACTIVE GALACTIC NUCLEI; SAMPLES; QUASARS; RADIATION; EMISSION; GALAXIES AB We examine the properties of the gamma-ray active galactic nuclei (AGNs) detected by EGRET. We calculate the evolution and luminosity function of the gamma-ray-loud AGNs, and we estimate the contribution this source class makes to the diffuse extragalactic gamma-ray background. These calculations are based on a sample of EGRET observations complete through the Compton Gamma-Ray Observatory observing Cycle 4. We use the V-e/V-a test to measure the luminosity evolution and the nonparametric c(-)-method to estimate the de-evolved luminosity function. We also consider inclusion in the 1 Jy radio catalog of Kuhr et al, (1981) as an additional criterion to help guard against selection effects resulting from incomplete redshift determinations for AGNs in our sample. Our results include evidence for a low-luminosity cutoff in the gamma-ray AGN luminosity distribution, a more precise estimate of the contribution of these objects to the diffuse extragalactic gamma-ray background, and constraints on the gamma-ray production mechanism based upon the statistics implied by relativistic beaming of the emission. We discuss the implications of these findings for models of AGN unification and the relationship of gamma-ray to radio emission. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. NASA, USRA, Montreal, PQ H3A 2T8, Canada. RP Chiang, J (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7653,4555 Overlook Ave, Washington, DC 20375 USA. NR 29 TC 95 Z9 95 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 APR 1 PY 1998 VL 496 IS 2 BP 752 EP 760 DI 10.1086/305403 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZG868 UT WOS:000073048100016 ER PT J AU Lazio, TJW Cordes, JM AF Lazio, TJW Cordes, JM TI The radial extent and warp of the ionized galactic disk. I. A VLBA survey of extragalactic sources toward the anticenter SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE dust, extinction; Galaxy, structure; H II regions; scattering; surveys ID 5 GHZ SURVEY; ANGULAR BROADENING MEASUREMENTS; NORTHERN MILKY-WAY; INTERSTELLAR SCATTERING; SUPERNOVA-REMNANTS; FREE-ELECTRONS; LATITUDES; CATALOG; PULSARS; CLOUDS AB We report multifrequency Very Long Baseline Array observations of 12 active galactic nuclei seen toward the Galactic anticenter. All of the sources are at \b\ < 10 degrees, and seven have \b\ < 0 degrees 5. Our VLBA observations can detect an enhancement in the angular broadening of these sources due to an extended H II disk, if the orientation of the H II disk in the outer Galaxy is similar to that of the H I disk. Such an extended H II disk is suggested by the C Iv absorption in a quasar's spectrum, the appearance of H I disks of nearby spiral galaxies, and models of Ly alpha cloud absorbers and the Galactic fountain. We detect 11 of the 12 sources at one or more frequencies; nine of the sources are compact and suitable for an angular broadening analysis. A preliminary analysis of the observed angular diameters suggests that the H 11 disk does not display considerable warping or flaring and does not extend to large Galactocentric distances (R greater than or similar to 100 kpc). A companion paper (Lazio & Cordes) combines these observations with those in the literature and presents a more comprehensive analysis. C1 Cornell Univ, Natl Astron & Ionosphere Ctr, Ithaca, NY 14853 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RP Lazio, TJW (reprint author), USN, Res Lab, Remote Sensing Div, Code 7210,4555 Overlook Ave SW, Washington, DC 20375 USA. EM lazio@spacenet.tn.cornell.edu; cordes@spacenet.tn.cornell.edu NR 42 TC 8 Z9 8 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD APR PY 1998 VL 115 IS 2 BP 225 EP 240 DI 10.1086/313084 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZF237 UT WOS:000072877400005 ER PT J AU Artigiani, R AF Artigiani, R TI Social information: the person is the message SO BIOSYSTEMS LA English DT Article; Proceedings Paper CT 2nd Conference on Foundations of Information Science - From Computers and Quantum Physics to Cells, Nervous Systems, and Societies CY JUN, 1994 CL VIENNA, AUSTRIA SP Univ Carlos III Madrid, Lab Artificial Intelligence, Univ Zaragoza C P S, Dept Elect & Electr Engn DE information; meaning; person; social systems; values-ethics-morals AB Assumptions that Shannon's concepts cannot extend to social systems are challenged by showing that social information measures the reduced uncertainties individuals have about the systemic effects of each other's behavior. The 'meaning' of individual actions is their collective consequences, which also measure reductions in systemic uncertainties about collective environments. Meaning is communicated through messages using media such as values, ethics and morals, which encourage individuals to act predictably and replicate the improbable behaviors characterizing particular societies. When individuals internalize meaning, their personal identities communicate societal priorities to future generations. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 USN Acad, Annapolis, MD 21402 USA. RP Artigiani, R (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0303-2647 J9 BIOSYSTEMS JI Biosystems PD APR PY 1998 VL 46 IS 1-2 BP 137 EP 144 DI 10.1016/S0303-2647(97)00091-9 PG 8 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA ZR001 UT WOS:000073925200018 PM 9648685 ER PT J AU Snow, AW Wohltjen, H AF Snow, AW Wohltjen, H TI Size-induced metal to semiconductor transition in a stabilized gold cluster ensemble SO CHEMISTRY OF MATERIALS LA English DT Article ID CONDUCTIVITY AB A size-induced transition from a positive to a negative temperature coefficient of electrical conductivity is displayed by thin films of a series of six dodecanethiol-stabilized gold cluster complexes with the gold core diameter progressively increasing from 1.7 to 7.2 nm. The size of the gold core may influence both its intrinsic conductivity and the charging energy barrier fcr tunneling to an adjacent monolayer-encapsulated cluster. C1 USN, Res Lab, Washington, DC 20375 USA. Microsensor Syst Inc, Bowling Green, KY 42103 USA. RP Snow, AW (reprint author), USN, Res Lab, Code 6120, Washington, DC 20375 USA. NR 12 TC 96 Z9 96 U1 2 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD APR PY 1998 VL 10 IS 4 BP 947 EP + DI 10.1021/cm970794p PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZK055 UT WOS:000073280400001 ER PT J AU Corwin, AL Simanjuntak, CH Ingkokusumo, G Sukri, N Larasati, RP Subianto, B Muslim, HZ Burni, E Laras, K Putri, RP Hayes, C Cox, N AF Corwin, AL Simanjuntak, CH Ingkokusumo, G Sukri, N Larasati, RP Subianto, B Muslim, HZ Burni, E Laras, K Putri, RP Hayes, C Cox, N TI Impact of epidemic influenza A-like acute respiratory illness in a remote jungle highland population in Irian Jaya, Indonesia SO CLINICAL INFECTIOUS DISEASES LA English DT Article ID VACCINES AB A suspected epidemic of unknown etiology was investigated in April/May 1996 in the remote jungle highlands of easternmost Indonesia. Trend analysis demonstrates the area-wide occurrence of a major respiratory infection outbreak in November 1995 through February 1996, The monthly mean rate of respiratory infection episodes for the peak outbreak months (2,477 episodes/100,000 persons) was significantly higher (P <.0001) than for the 34 months leading up to the outbreak (109 episodes/100,000 persons). Notable were the high attack rates, particularly among adults: 202 episodes/1,000 persons aged 20-50 years in one community. Excess morbidity attributed to the outbreak was an estimated 4,338 episodes. The overall case-fatality rate was 15.1% of outbreak cases. Laboratory evidence confirmed the circulation of influenza A/Taiwan/1/86-like viruses in the study population, and high hemagglutination inhibition titer responses were indicative of recent infections. Historical documents from neighboring Papua New Guinea highlight the role of influenza A virus in repeated area outbreaks. C1 USN, Med Res Unit 2, APO, AP 96520 USA. Minist Hlth, Natl Inst Hlth Res & Dev, Jakarta, Indonesia. Minist Hlth, Directorate Geb Communicable Dis Control & Enviro, Jakarta, Indonesia. Prov Hlth Serv Jayapura, Irian Jaya, Indonesia. Regency Hlth Serv Wamena, Irian Jaya, Indonesia. USN, Med Res Inst, Bethesda, MD USA. Ctr Dis Control & Prevent, Atlanta, GA 30333 USA. RP Corwin, AL (reprint author), USN, Med Res Unit 2, Box 3,Unit 8132, APO, AP 96520 USA. NR 22 TC 8 Z9 8 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 APR PY 1998 VL 26 IS 4 BP 880 EP 888 DI 10.1086/513917 PG 9 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZH279 UT WOS:000073091300015 PM 9564469 ER PT J AU Brook, I Frazier, EH AF Brook, I Frazier, EH TI Aerobic and anaerobic microbiology of retroperitoneal abscesses SO CLINICAL INFECTIOUS DISEASES LA English DT Article ID BACTEROIDES; BACTERIA AB The aerobic and anaerobic microbiology of various types of retroperitoneal abscesses was studied by review of the clinical and laboratory data for 161 patients treated between 1974 and 1990 for such abscesses. These included 109 anterior, 8 posterior, 21 retrofascial, and 23 pelvic retroperitoneal abscesses. A total of 472 organisms (2.9 isolates/specimen)-204 aerobic and facultative (1.3/specimen), and 268 anaerobic (1.7/specimen)-were recovered. Aerobes only were recovered from 34 abscesses (21%), anaerobes only from 34 (21%), and mixed aerobic and anaerobic bacteria from 93 (58%). Polymicrobial infection was present in 132 patients (82%). The predominant aerobic and facultative isolates were Escherichia coli (60 isolates), Klebsiella pneumoniae (20), Streptococcus group D (19), and Staphylococcus aureus (11). The predominant anaerobes were Peptostreptococcus species (95 isolates), Bacteroides fragilis group (66), Prevotella species (22), and Clostridium species (22). The number of anaerobes per site always was greater than the number of aerobic or facultative organisms and was especially high in pelvic abscesses. The number of aerobic and facultative organisms was especially high in pancreatic abscesses. These data highlight the polymicrobial aerobic-anaerobic nature of retroperitoneal abscesses. C1 USN Hosp, Dept Pediat & Infect Dis, Bethesda, MD 20814 USA. RP Brook, I (reprint author), POB 70412, Chevy Chase, MD 20814 USA. NR 26 TC 27 Z9 31 U1 1 U2 3 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 APR PY 1998 VL 26 IS 4 BP 938 EP 941 DI 10.1086/513947 PG 4 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZH279 UT WOS:000073091300025 PM 9564479 ER PT J AU Tsang, SK Maher, J AF Tsang, SK Maher, J TI Thyroid hemiagenesis accompanying a thyroglossal duct cyst: A case report SO CLINICAL NUCLEAR MEDICINE LA English DT Article DE hemiagenesis; thyroglossal duct cyst; thyroid AB A case of thyroid hemiagenesis discovered incidentally in a patient presenting with a thyroglossal duct cyst is reported, Thyroid embryology is briefly reviewed, Various characteristics of thyroid hemiagenesis and thyroglossal duct cysts are explored. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Radiol, San Diego, CA 92134 USA. RP Tsang, SK (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 13 TC 21 Z9 23 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0363-9762 J9 CLIN NUCL MED JI Clin. Nucl. Med. PD APR PY 1998 VL 23 IS 4 BP 229 EP 232 DI 10.1097/00003072-199804000-00008 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA ZE323 UT WOS:000072781100008 PM 9554195 ER PT J AU Oran, ES Weber, JW Stefaniw, EI Lefebvre, MH Anderson, JD AF Oran, ES Weber, JW Stefaniw, EI Lefebvre, MH Anderson, JD TI A numerical study of a two-dimensional H-2-O-2-Ar detonation using a detailed chemical reaction model SO COMBUSTION AND FLAME LA English DT Article ID SIMULATIONS; WAVES AB Two-dimensional computations of the propagation of a detonation in a low-pressure, argon-diluted mixture of hydrogen and oxygen were performed using a detailed chemical reaction mechanism. Cellular structure developed after an initial perturbation was applied to a one-dimensional solution placed on a two-dimensional grid. The energy-release pattern in a detonation cell showed that, in addition to the primary release of energy behind the Mach stem, there is a secondary energy release that starts about two-thirds of the way through the cell. Reignition, which occurs as transverse waves collide, results in an explosion that spreads over a region and releases a considerable amount of energy. Resolution tests showed convergence of the detonation mode (number of triple points or transverse waves) reached at the end of the computations, as well as global and local energy release. The computations were performed on massively parallel Connection Machines for which new approaches were developed to maximize the speed and efficiency of integrations. (C) 1998 by The Combustion Institute. C1 USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. USAF, Wright Lab, Propuls Syst Branch, Wright Patterson AFB, OH 45433 USA. Berkeley Res Associates, Springfield, VA 22151 USA. Royal Mil Acad, Dept Chem, B-1040 Brussels, Belgium. Univ Maryland, Dept Aerosp Engn, College Pk, MD 20742 USA. RP Oran, ES (reprint author), USN, Res Lab, Computat Phys & Fluid Dynam Lab, Code 6404, Washington, DC 20375 USA. NR 40 TC 121 Z9 137 U1 6 U2 20 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD APR PY 1998 VL 113 IS 1-2 BP 147 EP 163 DI 10.1016/S0010-2180(97)00218-6 PG 17 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA YW128 UT WOS:000071900700012 ER PT J AU Kang, MH Moore, AP Moskowitz, IS AF Kang, MH Moore, AP Moskowitz, IS TI Design and assurance strategy for the NRL Pump SO COMPUTER LA English DT Article AB Such systems suffer a host of disadvantages: They cost too much, lack user-friendly features and development environments, take too much time to evaluate and certify, and do not scale well for secure distributed computing. This lack of satisfactory security solutions is disturbing in light of the trend toward open and distributed computing, which increases a system's vulnerability to attack. The authors propose basing security solutions instead on a multiple single-level security architecture, which uses commercial (nonsecure) products for general-purpose computing and special-purpose high-assurance devices to separate data at different security levels. A multiple single-level architecture is a viable and practical solution to distributed multilevel secure computing. The keystone of this architecture is a trusted device that "pumps" data from a low security level to a higher one. The authors describe the software design and assurance argument strategy for this device, the Network NRL Pump, which can be used in any multilevel secure distributed architecture. C1 USN, Res Lab, Ctr High Assurance Comp Syst, Washington, DC 20375 USA. RP USN, Res Lab, Ctr High Assurance Comp Syst, Code 5540, Washington, DC 20375 USA. EM mkang@itd.nrl.navy.mil NR 10 TC 9 Z9 10 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 0018-9162 EI 1558-0814 J9 COMPUTER JI Computer PD APR PY 1998 VL 31 IS 4 BP 56 EP + DI 10.1109/2.666843 PG 11 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA ZE232 UT WOS:000072771400023 ER PT J AU Oxley, H AF Oxley, H TI ISI spins a web of science SO DATABASE LA English DT Database Review C1 USN, Res Lab, Tech Informat Ctr, Washington, DC 20375 USA. Naval Res Lab Lib, Washington, DC USA. RP Oxley, H (reprint author), USN, Res Lab, Ruth H Hooker Res Lib, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 0 TC 1 Z9 1 U1 0 U2 2 PU ONLINE INC PI WILTON PA 462 DANBURY RD, WILTON, CT 06897-2126 USA SN 0162-4105 J9 DATABASE JI Database PD APR-MAY PY 1998 VL 21 IS 2 BP 37 EP 40 PG 4 WC Computer Science, Information Systems; Information Science & Library Science SC Computer Science; Information Science & Library Science GA ZQ555 UT WOS:000073879800013 ER PT J AU Smith, SR Goldman, MP AF Smith, SR Goldman, MP TI Tumescent anesthesia in ambulatory phlebectomy SO DERMATOLOGIC SURGERY LA English DT Article ID LOCAL-ANESTHESIA; LIPOSUCTION AB BACKGROUND. Ambulatory phlebectomy is an elegant outpatient procedure for the removal of varicose veins. One of the keys to its success is the ability to perform the procedure under local anesthesia. A new form of anesthesia, tumescent anesthesia, has been developed for liposuction surgery and is now being expanded for use in other surgical disciplines. OBJECTIVE. TO determine the efficacy and safety as well as re view the use and advantages of tumescent anesthesia in ambulatory phlebectomy. METHODS. A retrospective review of phlebectomy cases performed in our offices under tumescent anesthesia. RESULTS. The reported level of intraoperative and postoperative pain was very low. The complication rate was consistent with other reports except for a higher number of hematomas (3.4%). CONCLUSIONS. Tumescent anesthesia provides a very safe, com fortable method of anesthetizing patients for ambulatory phlebectomy. Epinephrine, in appropriate concentrations, should be a part of all tumescent anesthetic solutions used for phlebectomy as it may decrease the incidence of hematoma. (C) 1998 by the American Society for Dermatologic Surgery. Inc. C1 Univ Calif San Diego, Dept Med, Div Dermatol, San Diego, CA 92103 USA. USN, Med Ctr, San Diego, CA 92152 USA. RP Goldman, MP (reprint author), Suite 2,850 Prospect St, La Jolla, CA 92037 USA. NR 10 TC 33 Z9 34 U1 1 U2 2 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 APR PY 1998 VL 24 IS 4 BP 453 EP 456 PG 4 WC Dermatology; Surgery SC Dermatology; Surgery GA ZJ013 UT WOS:000073170800006 PM 9568202 ER PT J AU Gray, JW Syverson, PF AF Gray, JW Syverson, PF TI A logical approach to multilevel security of probabilistic systems SO DISTRIBUTED COMPUTING LA English DT Article DE formal modeling; verification; knowledge; security; probabilistic systems ID KNOWLEDGE AB We set out a modal logic for reasoning about multilevel security of probabilistic systems. This logic contains expressions for time, probability, and knowledge. Making use of the Halpern-Tuttle framework for reasoning about knowledge and probability, we give a semantics for our logic and prove it is sound. We give two syntactic definitions of perfect multilevel security and show that their semantic interpretations are equivalent to earlier, independently motivated characterizations. We also discuss the relation between these characterizations of security and between their usefulness in security analysis. C1 Hong Kong Univ Sci & Technol, Dept Comp Sci, Kowloon, Hong Kong. USN, Res Lab, Ctr High Assurance Comp Syst, Washington, DC 20375 USA. RP Syverson, PF (reprint author), Hong Kong Univ Sci & Technol, Dept Comp Sci, Kowloon, Hong Kong. NR 44 TC 12 Z9 12 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0178-2770 J9 DISTRIB COMPUT JI Distrib. Comput. PD APR PY 1998 VL 11 IS 2 BP 73 EP 90 DI 10.1007/s004460050043 PG 18 WC Computer Science, Theory & Methods SC Computer Science GA ZN150 UT WOS:000073614900002 ER PT J AU Knoke, JD Gray, GC AF Knoke, JD Gray, GC TI Hospitalizations for unexplained illnesses among US veterans of the Persian Gulf War SO EMERGING INFECTIOUS DISEASES LA English DT Article ID DESERT-STORM; MORTALITY AB Persian Gulf War veterans have reported a variety of symptoms, many of which have not led to conventional diagnoses. We ascertained all active-duty U.S. military personnel deployed to the Persian Gulf War (552,111) and all Gulf War era military personnel not deployed (1,479,751) and compared their postwar hospitalization records (until 1 April 1996) for one or more of 77 diagnoses under the International Classification of Diseases (ICD-9) system. The diagnoses were assembled by the Emerging Infections Program, Centers for Disease Control and Prevention, and are here termed "unexplained illnesses." Deployed veterans were found to have a slightly higher risk of hospitalization for unexplained illness than the nondeployed. Most of the excess hospitalizations for the deployed were due to the diagnosis "illness of unknown cause" (ICD-9 code 799.9), and most occurred in participants of the Comprehensive Clinical Evaluation Program who were admitted for evaluation only. When the effect of participation in this program was removed, the deployed had a slightly lower risk than the nondeployed. These findings suggest that active-duty Gulf War veterans did not have excess unexplained illnesses resulting in hospitalization in the 4.67-year period following deployment. C1 USN, Hlth Res Ctr, San Diego, CA 92186 USA. RP Knoke, JD (reprint author), USN, Hlth Res Ctr, POB 85122, San Diego, CA 92186 USA. EM knoke@nhrc.navy.mil NR 25 TC 28 Z9 28 U1 1 U2 1 PU CENTER DISEASE CONTROL PI ATLANTA PA ATLANTA, GA 30333 USA SN 1080-6040 J9 EMERG INFECT DIS JI Emerg. Infect. Dis PD APR-JUN PY 1998 VL 4 IS 2 BP 211 EP 219 PG 9 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA ZQ811 UT WOS:000073905300008 PM 9621191 ER PT J AU Dyka, CT Ingel, RP AF Dyka, CT Ingel, RP TI Transient fluid-structure interaction in naval applications using the retarded potential method SO ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS LA English DT Article AB Submerged structures subjected to underwater shock remain a difficult and costly problem to analyze. In this work, the retarded potential (RP) method, which is a boundary element technique, is employed to discretize the fluid domain. The retarded potential program RPF is coupled to the ABAQUS non-linear finite element program to form ABAQUS/RPF. The Figueiredo method is used to convert the standard RP differential-delay equations for the fluid to simply delay equations, which are inherently more stable. ABAQUS/RPF is applied to both a rigid and elastic sphere. The Figueiredo approach is seen to extend significantly the stability range of the standard RP by a factor of approximately 10-20. Integration of the constant-pressure RP fluid element is shown to be very important to achieve this level of accuracy. Efforts to improve the Figueiredo approach using higher-order finite difference operators appear to have no effect on accuracy or stability. Stability of the coupled system is achieved by simply not extrapolating the structural accelerations. (C) 1998 published by Elsevier Science Ltd. All rights reserved. C1 Geocenters Inc, Ft Washington, MD 20749 USA. USN, Res Lab, Washington, DC 20375 USA. RP Dyka, CT (reprint author), Geocenters Inc, POB 441340, Ft Washington, MD 20749 USA. NR 15 TC 7 Z9 13 U1 0 U2 2 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 APR PY 1998 VL 21 IS 3 BP 245 EP 251 DI 10.1016/S0955-7997(98)00029-0 PG 7 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 100EW UT WOS:000074803100006 ER PT J AU Porch, D AF Porch, D TI For Europe or empire? French colonial ambitions and the European Army Plan SO ENGLISH HISTORICAL REVIEW LA English DT Book Review C1 USN, Postgrad Sch, Monterey, CA 93943 USA. RP Porch, D (reprint author), USN, Postgrad Sch, Monterey, CA 93943 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0013-8266 J9 ENGL HIST REV JI Engl. Hist. Rev. PD APR PY 1998 VL 113 IS 451 BP 543 EP 544 PG 2 WC History SC History GA 157KH UT WOS:000078059700179 ER PT J AU Ali, AI Blanco, T Buclatin, B AF Ali, AI Blanco, T Buclatin, B TI Goal network programs: A specialized algorithm and an application SO EUROPEAN JOURNAL OF OPERATIONAL RESEARCH LA English DT Article DE goal programming; network programming; assignment models ID NAVY PERSONNEL; ASSIGNMENT AB This paper presents a specialized network procedure for the solution of pure goal network programs with preemptive priorities. The specialization solves such goal network programs efficiently since it requires a modification only in the pricing rule of the network simplex algorithm. The algorithm is used to solve multiple goal network programs that arise in the assignment of naval personnel to jobs. Computational experience indicates that the specialization dominates the sequential linear goal programming procedure. (C) 1998 Elsevier Science B.V. C1 Univ Massachusetts, Sch Management Finance & Operat Management, Amherst, MA 01003 USA. USN, Ctr Personnel Res & Dev, San Diego, CA 92129 USA. RP Ali, AI (reprint author), Univ Massachusetts, Sch Management Finance & Operat Management, Amherst, MA 01003 USA. NR 12 TC 1 Z9 1 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-2217 J9 EUR J OPER RES JI Eur. J. Oper. Res. PD APR 1 PY 1998 VL 106 IS 1 BP 191 EP 197 DI 10.1016/S0377-2217(97)00208-7 PG 7 WC Management; Operations Research & Management Science SC Business & Economics; Operations Research & Management Science GA ZE158 UT WOS:000072764000024 ER PT J AU Nero, RW Thompson, CH Love, RH AF Nero, RW Thompson, CH Love, RH TI Low-frequency acoustic measurements of Pacific hake, Merluccius productus, off the west coast of the United States SO FISHERY BULLETIN LA English DT Article ID SOUND SCATTERING; FISH; DISTRIBUTIONS; SWIMBLADDER; STRENGTH AB Low-frequency volume scattering measurements were conducted by the Naval Research Laboratory (NRL) on the upper slope, slope base, and abyssal plain along the U.S. west coast between the Strait of Juan de Fuca, Washington, and Cape Mendocino, California. Comparisons of swimbladder radii estimated from resonances with those estimated from fish lengths obtained from quasisynoptic National Marine Fisheries Service (NMFS) trawl catches of Pacific hake, Merluccius productus, strongly suggest that the major source of the low-frequency scattering were Pacific hake. Estimates of hake density from the NRL low-frequency measurements and the NMFS acoustic, midwater trawl survey on the slope gave comparable values of 195-439 kg/ha and 91-369 kg/ha respectively. However, NRL measurements, up to 50 km offshore of the outer Limit of the NMFS survey, found densities of 270-300 kg/ha in layers peaking at 225 to 450 m depth. This finding suggests that high densities of hake may occur farther offshore of the traditional limit of NMFS surveys and at depths which may be difficult to survey with conventional fisheries sounders. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Nero, RW (reprint author), USN, Res Lab, Code 7174, Stennis Space Ctr, MS 39529 USA. NR 28 TC 10 Z9 11 U1 0 U2 3 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 USA SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD APR PY 1998 VL 96 IS 2 BP 329 EP 343 PG 15 WC Fisheries SC Fisheries GA ZG226 UT WOS:000072979800012 ER PT J AU Bosshard, M AF Bosshard, M TI Le 'Marabout de Blida' SO FRENCH REVIEW LA French DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Bosshard, M (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSN TEACH FRENCH PI CHAMPAIGN PA 57 EAST ARMORY AVE, CHAMPAIGN, IL 61820 USA SN 0016-111X J9 FR REV JI Fr. Rev. PD APR PY 1998 VL 71 IS 5 BP 873 EP 874 PG 2 WC Literature, Romance SC Literature GA ZG946 UT WOS:000073055900044 ER PT J AU Devereaux, CE Savides, TJ AF Devereaux, CE Savides, TJ TI Endoscopic ultrasound diagnosis of esophageal pseudodiverticulosis SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 USN, Med Ctr, San Diego, CA 92152 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 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 1998 VL 47 IS 4 SU S MA 486 BP AB145 EP AB145 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA ZK314 UT WOS:000073306800483 ER PT J AU McGuire, SE AF McGuire, SE TI Tongue ornament dislodged during removal of endotracheal tube: A previously unreported esophageal foreign body SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 USN, Med Ctr, San Diego, CA 92134 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 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 1998 VL 47 IS 4 SU S MA 193 BP AB72 EP AB72 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA ZK314 UT WOS:000073306800193 ER PT J AU Nedoluha, GE Siskind, DE Bacmeister, JT Bevilacqua, RM Russell, JM AF Nedoluha, GE Siskind, DE Bacmeister, JT Bevilacqua, RM Russell, JM TI Changes in upper stratospheric CH4 and NO2 as measured by HALOE and implications for changes in transport SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Measurements from HALOE indicate that there has been a significant decrease in CH4 in the middle to upper stratosphere from 1991-1997. Two dimensional model calculations suggest that a decrease in the tropical upwelling is the most plausible explanation for the CH4 decrease. The changes in CH4 resulting from solar cycle variations or changes in tropospheric CH4 and CFC emission rates are shown to be much smaller than the measured variations from similar to 35-45 km. The HALOE measurements of NO2 in the lower stratosphere near the equator also show an increase which is consistent with a reduction in the upward transport rate. Above similar to 40 km the NO2 measurements appear to be consistent with the net effect of opposing solar and dynamical trends. C1 USN, Res Lab, Washington, DC 20375 USA. Hampton Univ, Dept Phys, Hampton, VA 23668 USA. RP Nedoluha, GE (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. EM nedoluha@wvms.nrl.navy.mil NR 16 TC 30 Z9 37 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 APR 1 PY 1998 VL 25 IS 7 BP 987 EP 990 DI 10.1029/98GL00489 PG 4 WC Geosciences, Multidisciplinary SC Geology GA ZE646 UT WOS:000072815400014 ER PT J AU Rogers, DF AF Rogers, DF TI Computer-aided geometric design SO IEEE ANNALS OF THE HISTORY OF COMPUTING LA English DT Editorial Material ID B-SPLINE SURFACES C1 USN Acad, Dept Aerosp Engn, Annapolis, MD 21402 USA. RP Rogers, DF (reprint author), USN Acad, Dept Aerosp Engn, Annapolis, MD 21402 USA. NR 14 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 1058-6180 J9 IEEE ANN HIST COMPUT JI IEEE Ann. Hist. Comput. PD APR-JUN PY 1998 VL 20 IS 2 BP 44 EP 46 PG 3 WC Computer Science, Theory & Methods; History & Philosophy Of Science SC Computer Science; History & Philosophy of Science GA ZJ649 UT WOS:000073237800013 ER PT J AU Butler, KL Sarma, NDR Whitcomb, C Do Carmo, H Zhang, HB AF Butler, KL Sarma, NDR Whitcomb, C Do Carmo, H Zhang, HB TI Shipboard systems deploy automated protection SO IEEE COMPUTER APPLICATIONS IN POWER LA English DT Article C1 Texas A&M Univ, Dept Elect Engn, Power Syst Automat Lab, College Stn, TX 77843 USA. Univ Maryland, College Pk, MD 20742 USA. CMC Ltd, Div Res & Dev, Hyderabad, Andhra Pradesh, India. Off Naval Res, Ship Struct & Syst Sci & Technol Div ONR 334, Arlington, VA 22217 USA. Off Naval Res, Power Elect Bldg Block Project Team, Arlington, VA 22217 USA. RP Butler, KL (reprint author), Texas A&M Univ, Dept Elect Engn, Power Syst Automat Lab, College Stn, TX 77843 USA. NR 2 TC 43 Z9 48 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 0895-0156 J9 IEEE COMPUT APPL POW JI IEEE Comput. Appl. Power PD APR PY 1998 VL 11 IS 2 BP 31 EP 36 DI 10.1109/67.659624 PG 6 WC Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic SC Computer Science; Engineering GA ZE185 UT WOS:000072770000007 ER PT J AU Nicholas, M Ogden, PM Erskine, FT AF Nicholas, M Ogden, PM Erskine, FT TI Improved empirical descriptions for acoustic surface backscatter in the ocean SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE backscattering; reverberation; sea-surface ID BAND EXPLOSIVE CHARGES; SEA-SURFACE; SCATTERING AB Using Signals, Underwater Sound (SUS) explosive charges as broad-band acoustic sources, a high-quality set of surface scattering strengths was measured throughout the Critical Sea Test (CST) experiments, These measurements were made for wind speeds ranging from similar to 1 to 18 m/s and covered grazing angles from similar to 5 degrees to 30 degrees and frequencies from similar to 60 to 1000 Hz. A new empirical algorithm was developed based on a multiparameter multidimensional nonlinear fit to all the SUS data from CST-1 through CST-7. This new algorithm returns the surface scattering strength for a given frequency, grazing angle, and wind speed, The new formulation explored the use of backaveraging the wind speeds in time (as opposed to using the instantaneous wind speed) to allow for the influence of processes driven by the wind history. In this paper, details of the development of this new algorithm will be discussed, comparisons with earlier prediction algorithms (the Ogden-Erskine and Chapman-Harris algorithms) will be made, and the important differences between the various CST SUS data sets sill be highlighted and possible explanations will be offered, Finally, suggestions for further improvements to the algorithm will be made. C1 USN, Acoust Div, Res Lab, Washington, DC 20375 USA. Ctr Naval Anal, Alexandria, VA 22302 USA. RP Nicholas, M (reprint author), USN, Acoust Div, Res Lab, Washington, DC 20375 USA. NR 26 TC 9 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD APR PY 1998 VL 23 IS 2 BP 81 EP 95 DI 10.1109/48.664088 PG 15 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA ZH780 UT WOS:000073146900001 ER PT J AU Williams, KJ Dennis, ML Duling, IN Villarruel, CA Esman, RD AF Williams, KJ Dennis, ML Duling, IN Villarruel, CA Esman, RD TI A simple high-speed high-output voltage digital receiver SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE optical communication; optical fiber amplifiers; optical fiber communication; optical receivers; photodetectors; photodiodes; receivers; signal detection ID DOPED FIBER PREAMPLIFIER; 10 GB/S; SENSITIVITY AB We present measurements of a simple photoreceiver capable of generating 2.0 V at 15-Gb/s nonreturn-to-zero (NRZ), and 2.0 and 3.0 V at 24 and 10-Gb/s return-to-zero (RZ), respectively, directly from a p-i-n photodiode. Thus, this photoreceiver generates signal levels compatible with high-speed logic, clock recovery, and/or modulation with low-V-pi LiNbO3 modulators without the need for electrical postdetection amplification. The bit-error ratio (BER) is not compromised with this approach since this receiver generates clean eye diagrams with a BER of 10(-9) with -30-dBm input at 10 Gb/s. C1 USN, Res Lab, Washington, DC 20375 USA. RP Williams, KJ (reprint author), USN, Res Lab, Code 5670, Washington, DC 20375 USA. NR 10 TC 13 Z9 13 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD APR PY 1998 VL 10 IS 4 BP 588 EP 590 DI 10.1109/68.662603 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZD755 UT WOS:000072720300039 ER PT J AU Roman, JE Frankel, MY Williams, KJ Esman, RD AF Roman, JE Frankel, MY Williams, KJ Esman, RD TI Optical fiber cables for synchronous remoting of numerous transmitters/receivers SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE fiber-optic remoting; optical fiber cables; time-steered antenna arrays AB The relative fiber-to-fiber microwave phase changes induced in optical fiber cables by interfiber thermal and strain (bending-induced) gradients are reported. It is found that these changes are effectively minimized in cables where the fibers spin around the center member at a fast rate. Commercial "loose-tube" cables are found to preserve the fiber-to-fiber phases within 1 degrees at modulation frequencies as high as 18 GHz. These cables appear well suited for fiber-optic remoting of numerous phase-matched transmitters and receivers. C1 USN, Res Lab, Washington, DC 20375 USA. RP Roman, JE (reprint author), USN, Res Lab, Code 5672, Washington, DC 20375 USA. NR 4 TC 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 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD APR PY 1998 VL 10 IS 4 BP 591 EP 593 DI 10.1109/68.662604 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZD755 UT WOS:000072720300040 ER PT J AU Matthews, PJ Biernacki, PD Esman, RD AF Matthews, PJ Biernacki, PD Esman, RD TI RF phase-noise performance of a two-channel optical downconverting link for microwave phase detection SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE frequency conversion; optical fiber applications; phase detection; phase noise; receiving antennas AB The phase-noise performance of a low-noise preamplified two-channel optical downconverting link is measured for the first time. The downconverter is capable of operation over a 2-18-GHz bandwidth with a fixed intermediate frequency of 160 MHz. Results show that a two-channel configuration used as a remote microwave phase detector exhibits performance equivalent to a typical microwave mixer. C1 USN, Res Lab, Washington, DC 20375 USA. RP Matthews, PJ (reprint author), USN, Res Lab, Code 5672, Washington, DC 20375 USA. NR 5 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD APR PY 1998 VL 10 IS 4 BP 594 EP 596 DI 10.1109/68.662605 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA ZD755 UT WOS:000072720300041 ER PT J AU Chen, VC Qian, S AF Chen, VC Qian, S TI Joint time-frequency transform for radar range Doppler imaging SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID WIGNER DISTRIBUTION; SIGNAL ANALYSIS; TOOL AB Conventional radar imaging uses the Fourier transform to retrieve Doppler information. However, due to the complex motion of a target, the Doppler frequency shifts are actually time-varying. By using the Fourier transform, the Doppler spectrum becomes smeared and the image is blurred. Without resorting to sophisticated motion compensation algorithms, the image blurring problem can be resolved with the joint time-frequency transform. High-resolution time-frequency transforms are investigated, and examples of applications to radar imaging of single and multiple targets with complex motion are given. C1 USN, Res Lab, Div Radar, Washington, DC 20375 USA. Natl Instruments Corp, DSP Grp, Austin, TX 78730 USA. RP Chen, VC (reprint author), USN, Res Lab, Div Radar, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 17 TC 193 Z9 249 U1 0 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 1998 VL 34 IS 2 BP 486 EP 499 DI 10.1109/7.670330 PG 14 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA ZH484 UT WOS:000073115700013 ER PT J AU Blair, WD Brandt-Pearce, M AF Blair, WD Brandt-Pearce, M TI Unresolved Rayleigh target detection using monopulse measurements SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article AB When the returns from two or more targets interfere (i.e., the signals are not resolved in the frequency or time domains) in a monopulse radar system, the direction-of-arrival (DOA) estimate indicated by the monopulse ratio can wander far beyond the angular separation of the targets. Generalized maximum likelihood (GML) detection of the presence of unresolved Rayleigh targets is developed with probability density functions (pdfs) conditioned on the measured amplitude of the target echoes. The Neyman-Pearson detection algorithm uses both the in-phase and quadrature portions of the monopulse ratio and requires no a priori knowledge of the signal-to-noise ratio (SNR) or DOA of either target. Receiver operating characteristic (ROC) curves are given along with simulation results that illustrate the performance and application of the algorithm. C1 Univ Virginia, Dept Elect Engn, Charlottesville, VA 22903 USA. Naval Surface Warfare Ctr, Silver Spring, MD 20903 USA. RP Blair, WD (reprint author), Georgia Tech Res Inst, SEAL, RSD, Atlanta, GA 30332 USA. RI Brandt-Pearce, Maite/B-3121-2013 OI Brandt-Pearce, Maite/0000-0002-2566-8280 NR 13 TC 58 Z9 77 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 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 1998 VL 34 IS 2 BP 543 EP 552 DI 10.1109/7.670335 PG 10 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA ZH484 UT WOS:000073115700018 ER PT J AU Blair, WD Brandt-Pearce, M AF Blair, WD Brandt-Pearce, M TI Statistical description of monopulse parameters for tracking Rayleigh targets SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID NOISE AB The conditional probability density function (pdf) is developed for each monopulse measurement of a Rayleigh target by conditioning the pdf of the complex monopulse ratio on the measured amplitude of the sum signal. The conditional pdf is used to develop the conditional Cramer-Rao Lower Bound (CRLB) for any unbiased estimator of the direction-of-arrival (DOA). Conditional maximum likelihood (CML) and conditional method of moments (CMM) estimators of the DOA are developed along with estimates of the variances associated with the monopulse ratio and DOA estimate. Using simulation results, the performances of the CML and CMM estimators of the DOA are compared with the performance of standard monopulse ratio and the performances of the variance estimators are also studied. C1 Univ Virginia, Dept Elect Engn, Charlottesville, VA 22903 USA. Naval Surface Warfare Ctr, Silver Spring, MD USA. RP Blair, WD (reprint author), Georgia Tech Res Inst, SEAL, RSD, Atlanta, GA 30332 USA. RI Brandt-Pearce, Maite/B-3121-2013 OI Brandt-Pearce, Maite/0000-0002-2566-8280 NR 9 TC 45 Z9 48 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 APR PY 1998 VL 34 IS 2 BP 597 EP 611 DI 10.1109/7.670340 PG 15 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA ZH484 UT WOS:000073115700023 ER PT J AU Wang, YX Ling, H Chen, VC AF Wang, YX Ling, H Chen, VC TI ISAR motion compensation via adaptive joint time-frequency technique SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Letter ID SYNTHETIC-APERTURE RADAR; TARGET; AUTOFOCUS AB A novel approach for inverse synthetic aperture radar (ISAR) imaging is presented for both target translational motion and rotational motion nonuniformity compensation. The basic idea is to perform Doppler tracking to Individual scatterers via an adaptive joint time-frequency (AJTF) projection technique. After maximizing the projection of the phase function to a set of basis functions In time-frequency plane, the Doppler frequency drift of the strongest scatterer in the range bin is automatically tracked out and the multiple prominent point processing (PPP) scheme is implemented to eliminate both the translational motion error and rotational motion nonuniformity. Further the azimuth spacing can be estimated, which permits polar reformatting of the original collected data. C1 Univ Texas, Dept Elect & Comp Engn, Austin, TX 78712 USA. USN, Res Lab, Airborne Branch, Washington, DC 20375 USA. RP Wang, YX (reprint author), Univ Texas, Dept Elect & Comp Engn, Austin, TX 78712 USA. NR 15 TC 123 Z9 133 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 1998 VL 34 IS 2 BP 670 EP 677 DI 10.1109/7.670350 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA ZH484 UT WOS:000073115700032 ER PT J AU Skinner, JP Kent, BM Wittmann, RC Mensa, DL Andersh, DJ AF Skinner, JP Kent, BM Wittmann, RC Mensa, DL Andersh, DJ TI Normalization and interpretation of radar images SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE radar imaging AB Calibrated radar images are often quantified as radar cross section. This interpretation, which is not strictly correct, can lead to misunderstanding of test target scattering properties. To avoid confusion, we recommend that a term such as "scattering brightness" (defined below) be adopted as a standard label for image-domain data. C1 AF Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, Signature Technol Off, Wright Patterson AFB, OH 45433 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. USN, Ctr Weap, Pt Mugu, CA USA. Demaco Inc, Champaign, IL 61820 USA. RP Skinner, JP (reprint author), Dept AF, Wright Patterson AFB, OH USA. NR 5 TC 4 Z9 4 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 APR PY 1998 VL 46 IS 4 BP 502 EP 506 DI 10.1109/8.664113 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA ZG443 UT WOS:000073002800006 ER PT J AU Sellami, L Newcomb, RW AF Sellami, L Newcomb, RW TI Lossy synthesis of digital lattice filters SO IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-ANALOG AND DIGITAL SIGNAL PROCESSING LA English DT Article DE computable lossy filters; digital lattice filters; passive synthesis AB A new method for converting a lossless cascade lattice realization of a real, stable, single-input, single-output (ARMAn, m) filter, with a lossy constant terminating one-port section, to a lossy realization is proposed. The conversion process is carried out through the factorization of the transfer scattering matrix of a two-port equivalent of the terminating section and the distribution of the loss term, embedded in this matrix, among the lossless lattice sections according to some desirable pattern, The cascade is then made computable through the extraction of right-matched J-unitary normalization sections. The technique applies to both degree-one and degree-two lattice sections, and is rendered systematic owing to the particular lossless lattice structure used. The motivation for this work lies in the synthesis of a pipeline of digital cochlea lattices with loss suitable for hearing impairment diagnosis via Kemp echoes. C1 USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. RP Sellami, L (reprint author), USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1057-7130 J9 IEEE T CIRCUITS-II JI IEEE Trans. Circuits Syst. II-Analog Digit. Signal Process. PD APR PY 1998 VL 45 IS 4 BP 512 EP 518 DI 10.1109/82.663809 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA ZH783 UT WOS:000073147200008 ER PT J AU Krowne, CM AF Krowne, CM TI Implicit 3-D dyadic Green's function using self-adjoint operators for inhomogeneous planar ferrite circulator with vertically layered external material employing mode-matching SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE dyadic Green's function; inhomogeneous ferrite; microstrip circulator; mode-matching; self-adjoint operator ID CYLINDRICAL DIELECTRIC RESONATOR; DEPOSITION; FREQUENCY; FILMS AB Self-adjoint operators are found for the differential equations describing the a-dependent field variation in the medium external to the ferrite microstrip circulator puck, The external medium is, in general, inhomogeneously layered, consisting of media with permittivity properties, magnetic properties, or both. Eigenvalue equations characterizing the radially sectioned medium outside the puck are found, as are the eigenvectors. When the z-dependent parts are multiplied with the radial and azimuthal dependences, the complete three-dimensional (3-D) field expressions are determined, Source-constraint equations (representing microstrip lines) driving the circulator are then combined with the mode-matching technique to obtain in direct space, implicit dyadic Green's function elements, Mode orthogonality is employed to encourage sparsity in matrix system development where appropriate or convenient, The implicit Green's function is particularly useful because field information and s-parameters may be found in real space, completely avoiding typical inverse transformations. C1 USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Washington, DC 20375 USA. RP USN, Res Lab, Div Elect Sci & Technol, Microwave Technol Branch, Code 6850-3, Washington, DC 20375 USA. NR 17 TC 6 Z9 6 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9480 EI 1557-9670 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD APR PY 1998 VL 46 IS 4 BP 359 EP 377 DI 10.1109/22.664137 PG 19 WC Engineering, Electrical & Electronic SC Engineering GA ZE684 UT WOS:000072819800006 ER PT J AU Mueller, K Moller, T Swan, JE Crawfis, R Shareef, N Yagel, R AF Mueller, K Moller, T Swan, JE Crawfis, R Shareef, N Yagel, R TI Splatting errors and antialiasing SO IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS LA English DT Article; Proceedings Paper CT 8th Annual IEEE Conference on Visualization CY OCT 19-24, 1997 CL PHOENIX, AZ SP IEEE Comp Soc, Tech Comm Comp Graph, ACM, SIGGRAPH DE volume rendering; splatting; direct volume rendering; resampling; reconstruction; antialiasing; perspective projection; motion blur ID VISUALIZATION AB This paper describes three new results for volume rendering algorithms utilizing splatting. First, an antialiasing extension to the basic splatting algorithm is introduced that mitigates the spatial aliasing for high-resolution volumes. Aliasing can be severe for high-resolution volumes or volumes where a high depth of field leads to converging samples along the perspective axis. Next, an analysis of the common approximation errors in the splatting process for perspective viewing is presented. In this context, we give different implementations, distinguished by efficiency and accuracy, for adding the splat contributions to the image plane. We then present new results in controlling the splatting errors and also show their behavior in the framework of our new antialiasing technique. Finally, current work in progress on extensions to splatting for temporal antialiasing is demonstrated. Here, we present a simple but highly effective scheme for adding motion blur to fast moving volumes. C1 Ohio State Univ, Dept Informat & Comp Sci, Columbus, OH 43210 USA. Ohio State Univ, Adv Comp Ctr Arts & Design, Columbus, OH 43210 USA. USN, Res Lab, Washington, DC 20375 USA. RP Ohio State Univ, Dept Informat & Comp Sci, 2015 Neil Ave, Columbus, OH 43210 USA. EM mueller@cis.ohio-state.edu; moeller@cis.ohio-state.edu; swan@acm.org; crawfis@cis.ohio-state.edu; shareef@cis.ohio-state.edu; yagel@cis.ohio-state.edu NR 16 TC 27 Z9 29 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 1077-2626 EI 1941-0506 J9 IEEE T VIS COMPUT GR JI IEEE Trans. Vis. Comput. Graph. PD APR-JUN PY 1998 VL 4 IS 2 BP 178 EP 191 DI 10.1109/2945.694987 PG 14 WC Computer Science, Software Engineering SC Computer Science GA ZX108 UT WOS:000074480200008 ER PT J AU McCraty, R Barrios-Choplin, B Rozman, D Atkinson, P Watkins, AD AF McCraty, R Barrios-Choplin, B Rozman, D Atkinson, P Watkins, AD TI The impact of a new emotional self-management program on stress, emotions, heart rate variability, DHEA and cortisol SO INTEGRATIVE PHYSIOLOGICAL AND BEHAVIORAL SCIENCE LA English DT Article ID SECRETORY PATTERN; ADRENAL-FUNCTION; DEHYDROEPIANDROSTERONE; DISEASE; WOMEN; AMYGDALA; CANCER; MEN; ATHEROSCLEROSIS; NEUROENDOCRINE AB This study examined the effects on healthy adults of a new emotional selfmanagement program, consisting of two key techniques, "Cut-Thru" and the "Heart Lock-In." These techniques are designed to eliminate negative thought loops and promote sustained positive emotional states. The hypotheses were that training and practice in these techniques would yield lowered levels of stress and negative emotion and cortisol, while resulting in increased positive emotion and DHEA levels over a one-month period. in addition, we hypothesized that increased coherence in heart rate variability patterns would be observed during the practice of the techniques. Forty-five healthy adults participated in the study, fifteen of whom acted as a comparison group for the psychological measures. Salivary DHEA/DHEAS and cortisol levels were measured, autonomic nervous system function was assessed by heart rate variability analysis, and emotions were measured using a psychological questionnaire. Individuals in the experimental group were assessed before and four weeks after receiving training in the self-management techniques. The experimental group experienced significant increases in the positive affect scales of Caring and Vigor and significant decreases in the negative affect scales of Guilt, Hostility, Burnout, Anxiety and Stress Effects, while no significant changes were seen in the comparison group. There was a mean 23 percent reduction in cortisol and a 100 percent increase in DHEA/DHEAS in the experimental group. DHEA was significantly and positively related to the affective state Warmheartedness, whereas cortisol was significantly and positively related to Stress Effects. Increased coherence in heart rate variability patterns was measured in 80 percent of the experimental group during the use of the techniques. The results suggest that techniques designed to eliminate negative thought loops can have important positive effects on stress, emotions and key physiological systems. The implications are that relatively inexpensive interventions may dramatically and positively impact individuals' health and well-being. Thus, individuals may have greater control over their minds, bodies and health than previously suspected. C1 Inst HeartMath, Boulder Creek, CA 95006 USA. USN, Postgrad Sch, Monterey, CA USA. Southampton Gen Hosp, Southampton SO9 4XY, Hants, England. RP McCraty, R (reprint author), Inst HeartMath, 14700 W Pk Ave, Boulder Creek, CA 95006 USA. EM rollin@heartmath.org NR 82 TC 58 Z9 60 U1 3 U2 28 PU TRANSACTION PERIOD CONSORTIUM PI NEW BRUNSWICK PA DEPT 3091 RUTGERS-THE STATE UNIV OF NJ, NEW BRUNSWICK, NJ 08903 USA SN 1053-881X J9 INTEGR PHYS BEH SCI JI Integr. Physiol. Behav. Sci. PD APR-JUN PY 1998 VL 33 IS 2 BP 151 EP 170 DI 10.1007/BF02688660 PG 20 WC Psychology, Biological; Neurosciences SC Psychology; Neurosciences & Neurology GA 113XK UT WOS:000075579000009 PM 9737736 ER PT J AU Lindner, JF Meadows, BK Marsh, TL Ditto, WL Bulsara, AR AF Lindner, JF Meadows, BK Marsh, TL Ditto, WL Bulsara, AR TI Can neurons distinguish chaos from noise? SO INTERNATIONAL JOURNAL OF BIFURCATION AND CHAOS LA English DT Article; Proceedings Paper CT International Conference on Nonlinear Dynamics and Chaos - Applications in Physics Biology and Medicine CY JUL 08-14, 1996 CL SARATOV, RUSSIA ID COOPERATIVE BEHAVIOR; MODEL AB Recent studies suggesting evidence for determinism in the stochastic activity of the heart and brain have sparked an important scientific debate: Do biological systems exploit chaos or are they merely noisy? Here, we analyze the spike interval statistics of a simple integrate-and-fire model neuron to investigate how a real neuron might process noise and chaos, and possibly differentiate between the two. In some cases, our model neuron readily distinguishes noise from chaos, even discriminating among chaos characterized by different Lyapunov exponents. However, in other cases, the model neuron does not decisively differentiate noise from chaos. In these cases, the spectral content of the input signal may be more significant than its phase space structure, and higher-order spectral characterizations may be necessary to distinguish its response to chaotic or noisy inputs. C1 Georgia Inst Technol, Sch Phys, Appl Chaos Lab, Atlanta, GA 30332 USA. Coll Wooster, Wooster, OH 44691 USA. USN, Control & Ocean Surveillance Ctr, RDT&E Div, San Diego, CA 92152 USA. RP Georgia Inst Technol, Sch Phys, Appl Chaos Lab, Atlanta, GA 30332 USA. OI Ditto, William/0000-0002-7416-8012 NR 19 TC 9 Z9 9 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0218-1274 EI 1793-6551 J9 INT J BIFURCAT CHAOS JI Int. J. Bifurcation Chaos PD APR PY 1998 VL 8 IS 4 BP 767 EP 781 DI 10.1142/S0218127498000565 PG 15 WC Mathematics, Interdisciplinary Applications; Multidisciplinary Sciences SC Mathematics; Science & Technology - Other Topics GA 125VH UT WOS:000076257400013 ER PT J AU Kremliovsky, M Kadtke, J Inchiosa, M Moore, P AF Kremliovsky, M Kadtke, J Inchiosa, M Moore, P TI Characterization of dolphin acoustic echo-location data using a dynamical classification method SO INTERNATIONAL JOURNAL OF BIFURCATION AND CHAOS LA English DT Article; Proceedings Paper CT International Conference on Nonlinear Dynamics and Chaos - Applications in Physics Biology and Medicine CY JUL 08-14, 1996 CL SARATOV, RUSSIA ID SIGNALS AB Many methods for time series analysis derived from nonlinear dynamical systems theory have been developed in the last decade, and have demonstrated remarkable results in a variety of simulated, experimental, and real applications. Classification of time series based on the underlying dynamical generator is also potentially powerful, and we have previously presented a method for dynamical classification based on empirically estimated sets of nonlinear ordinary differential equations, i.e. global dynamical models. A particularly useful area of application for such methods may be biologic and medical data analysis, where few quantitative methods exist for the highly complex time evolutions. Here, as an example of the application of such classification methods, we present an analysis of data of the acoustic pulse trains produced by dolphins as they attempt to echo-locate objects in an ocean environment, which is derived from a controlled experimental framework. C1 Univ Calif San Diego, Inst Pure & Appl Phys Sci, La Jolla, CA 92093 USA. USN, Control & Ocean Surveillance Ctr, San Diego, CA 92152 USA. RP Kremliovsky, M (reprint author), Univ Calif San Diego, Inst Pure & Appl Phys Sci, MS-0360,9500 Gilman Dr, La Jolla, CA 92093 USA. NR 9 TC 8 Z9 8 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0218-1274 J9 INT J BIFURCAT CHAOS JI Int. J. Bifurcation Chaos PD APR PY 1998 VL 8 IS 4 BP 813 EP 823 DI 10.1142/S0218127498000619 PG 11 WC Mathematics, Interdisciplinary Applications; Multidisciplinary Sciences SC Mathematics; Science & Technology - Other Topics GA 125VH UT WOS:000076257400018 ER PT J AU Smith, KJ Skelton, HG Ruiz, N Samlaska, K Wagner, KF AF Smith, KJ Skelton, HG Ruiz, N Samlaska, K Wagner, KF CA Mil Med Consortium Advancement Mil Med TI Cutaneous reactions at the site of post-infection gp160 vaccination therapy in HIV-1+ patients SO INTERNATIONAL JOURNAL OF DERMATOLOGY LA English DT Article ID IMMUNODEFICIENCY-VIRUS INFECTION; T-HELPER; TYPE-1; PATHOGENESIS; PERSPECTIVES; GRANULOMAS AB Background Post-infection vaccination with human immunodeficiency virus type 1 (HIV-1) specific antigens has been hypothesized as a mechanism for generating a more effective immune response to the HIV-1 virus. Cutaneous reactions at the site of immunization may provide information on the pattern of immune activation induced by the vaccine. Objective To evaluate exaggerated local cutaneous reactions in eight HIV-1 + patients enrolled in a phase I and II gp160 vaccine study. Methods Cutaneous biopsy specimens were obtained and evaluated using routine histologic, immunofluorescence, and immunohistochemical techniques. Results A mononuclear cell infiltrate with tissue eosinophilia, in some cases forming flame figures, was present on histologic sections. There was no evidence of immune complex deposition. Activated T-helper cells formed a major portion of the mononuclear cell infiltrate. Conclusions A delayed-type hypersensitivity reaction, mediated by T cells with a T-helper 2 cytokine pattern, was favored by clinical and histologic features. The most likely antigen stimulating this reaction is residual lepidopteran used in the preparation of the vaccine; however, baculovirus antigens may also play a role. In addition, the adjuvant, aluminum phosphate, as well as the underlying patterns of immune dysregulation present in H1V-1 + patients, may potentiate these reactions. C1 USA, Med Res Inst Chem Def, Aberdeen Proving Ground, MD 21010 USA. Armed Forces Inst Pathol, Washington, DC 20306 USA. USN, Natl Med Ctr, Bethesda, MD 20084 USA. Walter Reed Army Med Ctr, Washington, DC 20307 USA. RP Skelton, HG (reprint author), 6514 Rockhurst Rd, Bethesda, MD 20817 USA. NR 27 TC 4 Z9 4 U1 0 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0011-9059 J9 INT J DERMATOL JI Int. J. Dermatol. PD APR PY 1998 VL 37 IS 4 BP 293 EP 298 DI 10.1046/j.1365-4362.1998.00272.x PG 6 WC Dermatology SC Dermatology GA ZL062 UT WOS:000073395000014 PM 9585904 ER PT J AU Harvey, DP Bonenberger, RJ Wolla, JM AF Harvey, DP Bonenberger, RJ Wolla, JM TI Effects of sequential cyclic and monotonic loadings on damage accumulation in nickel 270 SO INTERNATIONAL JOURNAL OF FATIGUE LA English DT Article DE precycling; prestrain; damage accumulation ID FATIGUE BEHAVIOR; STAINLESS-STEEL; ENERGY; METALS; STRESS AB Specimens of polycrystalline nickel 270 were tested by subjecting them to loading paths of either (1) monotonic prestrain followed by strain controlled cyclic loading to failure or (2) strain controlled precycling followed by monotonic loading to failure. The effects of initial condition as produced by cold working or annealing, cyclic strain range, frequency and degree of monotonic prestrain on subsequent fatigue behavior were investigated. The effects of precycling on the subsequent monotonic tensile behavior of the test material were also studied. The heat dissipated from the specimens under fatigue loading was measured. It was found that 76.6% of the irreversible work was dissipated as heat; the remaining portion caused material damage. The relative effects of monotonic prestrain on subsequent cyclic behavior were more harmful than the effects of precycling on subsequent monotonic behavior. The results showed that the energy absorbed by the material, which corresponds to damage, is a function of various loading parameters and is therefore path dependent under these conditions. (C) 1998 Elsevier Science Ltd. C1 USN, Res Lab, Mech Mat Branch, Washington, DC 20375 USA. FM Technol Inc, Fairfax, VA 22032 USA. USN, Res Lab, Phys Met Branch, Washington, DC 20375 USA. RP Harvey, DP (reprint author), USN, Res Lab, Mech Mat Branch, Washington, DC 20375 USA. NR 30 TC 22 Z9 22 U1 0 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-1123 J9 INT J FATIGUE JI Int. J. Fatigue PD APR PY 1998 VL 20 IS 4 BP 291 EP 300 DI 10.1016/S0142-1123(97)00138-2 PG 10 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA ZP203 UT WOS:000073728100004 ER PT J AU Twiggs, LB Hartenbach, E Saltzman, AK King, LA AF Twiggs, LB Hartenbach, E Saltzman, AK King, LA TI Metastatic placental site trophoblastic tumor SO INTERNATIONAL JOURNAL OF GYNECOLOGY & OBSTETRICS LA English DT Article; Proceedings Paper CT VIIIth World Congress on Gestational Trophoblastic Diseases CY NOV 03-06, 1996 CL SEOUL, SOUTH KOREA DE trophoblastic disease; placental site trophoblastic tumor; trophoblastic pseudotumor; malignant trophoblastic disease ID PSEUDO-TUMOR; DISEASE AB Since our publication, which first defined the malignant potential of placental site trophoblastic tumor (PSTT), we have had a keen interest in this rare, unique entity. This histologic entity is noted by its monomorphic population of trophoblast-like cells which are classified as originating in the intermediate trophoblast. These cells contain hymman placental lactogen (HPL). This is in contrast to cytotrophoblastic and syncytiotrophblastic tissues as the histologic, cytologic and inmunohistochemical stain characteristics are disparate. Its rarity and the wide spectrum of clinical behavior combined with the lack of sensitivity of serum levels of beta hCG in predicting disease recurrence and spread have lead to anecdotal reports outlining clinical management. Most discerning to the clinician is the high mortality of metastatic placental site trophoblastic tumor. At our institution, we have treated two patients with a metastatic disease with a successful conclusion. The durability of responses is 3 and 8 years. This report will present these patients in detail and define the important characteristics of successful treatment. The use of dose-intensive, multi-agent chemotherapy, early intervention when metastatic disease is discovered, imaging techniques to define disease spread, surgery fur localized disease and the use of growth factors, most notably granulocyte colony-stimulating factor (G-CSF), are the fundamentals of clinical care of placental site trophoblastic tumor in patients with metastatic placental site trophoblastic tumor. C1 Univ Wisconsin, Womens Canc Ctr, Madison, WI 53706 USA. USN, Med Ctr, Dept Obstet & Gynecol, Div Gynecol Oncol, San Diego, CA 92152 USA. Dept Obstet & Gynecol, Div Gynecol Oncol, Miami, FL USA. RP Twiggs, LB (reprint author), Univ Wisconsin, Womens Canc Ctr, Madison, WI 53706 USA. NR 13 TC 17 Z9 18 U1 0 U2 0 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0020-7292 J9 INT J GYNECOL OBSTET JI Int. J. Gynecol. Obstet. PD APR PY 1998 VL 60 SU 1 BP S51 EP S55 DI 10.1016/S0020-7292(98)80005-2 PG 5 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 138KK UT WOS:000076970900007 PM 9833615 ER PT J AU Bonafede, SJ Brady, RF AF Bonafede, SJ Brady, RF TI Compositional effects on the fouling resistance of fluorourethane coatings SO JOCCA-SURFACE COATINGS INTERNATIONAL LA English DT Article AB The property perhaps most frequently associated with fluorinated polymers is their ability to prevent or limit adhesive bonding to themselves. This property forms the basis for such commercial and industrial applications as nonstick cooking utensils, finishes for carpets, clothing and leather goods, prosthetic devices and surgical implants, magnetic recording material, and surface coatings for industrial, architectural, automotive and marine use. This work concentrates on coatings which resist strong bonds to marine organisms and discourage the attachment of marine growth to the hull of a ship. The aim is to develop a coating that weakens or eliminates the adhesive bond between fouling organisms and the coating. Then the fouling would be dislodged by relatively weak mechanical forces such as the weight of the fouling or the sheer as the ship moves through the water. The intention is to avoid toxins such as heavy metals which may accumulate in the environment. C1 USN, Res Lab, Div Chem, Washington, DC 20376 USA. RP Bonafede, SJ (reprint author), USN, Res Lab, Div Chem, Code 6123,4555 Overlook Ave SW, Washington, DC 20376 USA. NR 17 TC 1 Z9 1 U1 2 U2 6 PU OIL COLOUR CHEM ASSN PI MIDDLESEX PA PRIORY HOUSE-967 HARROW RD WEMBLEY, MIDDLESEX, ENGLAND HA0 2SF SN 1356-0751 J9 JOCCA-SURF COAT INT JI JOCCA-Surf. Coat. Int. PD APR PY 1998 VL 81 IS 4 BP 181 EP + PG 6 WC Chemistry, Applied; Engineering, Chemical; Materials Science, Coatings & Films SC Chemistry; Engineering; Materials Science GA V2642 UT WOS:000165536400003 ER PT J AU Gardner, LI Harrison, SH Hendrix, CW Blatt, SP Wagner, KF Chung, RCY Harris, RW Cohn, DL Burke, DS Mayers, DL AF Gardner, LI Harrison, SH Hendrix, CW Blatt, SP Wagner, KF Chung, RCY Harris, RW Cohn, DL Burke, DS Mayers, DL CA Military Med Consortium Appl Retroviral Res TI Size and duration of zidovudine benefit in 1003 HIV-infected patients: US Army, Navy, and Air Force natural history data SO JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY LA English DT Article DE HIV early stage natural history; zidovudine; HIV epidemiology ID IMMUNODEFICIENCY-VIRUS-INFECTION; CUBIC MILLIMETER; CONTROLLED TRIAL; CELL COUNTS; AIDS; PROGRESSION; THERAPY; AZT AB Objectives: The study's objectives were to determine the size and duration of benefits of early versus delayed versus late treatment with zidovudine (ZDV) on disease progression and mortality in HIV-infected patients, and whether patients rapidly progressing before ZDV treatment had a different outcome from those not rapidly progressing before ZDV. Design: The design was an inception cohort of 1003 HIV-infected patients. One hundred and seventy-four of the 1003 patients were treated before CD4 counts fell to 1400 x 10(9)/L, ("early treatment"); 183 of 1003 patients were treated after CD4 counts fell to <400 x 10(9)/L but before clinical disease developed ("delayed treatment"); and 646 of the 1003 patients had either been treated after clinical disease developed or had not been treated at all by the end of follow-up ("late treatment"). Outcomes were progression to clinical HIV disease and mortality. Results: The relative risk (RR) of progression for early versus delayed treatment was 0.58 (p < .03), and durability of ZDV benefits on progression was estimated at no more than 2.0 years; however, this estimate had wide confidence intervals. The RR of progression for delayed versus late treatment was 0.54 p < .0001, and durability of ZDV benefits was estimated at 1.74 years; this estimate had narrow confidence intervals. Survival was better for the early versus delayed treatment (RR = 0.55), but this difference was not statistically significant. In the subgroup of patients with more rapid CD4 decline prior to ZDV therapy, significant benefits on progression were observed for early versus delayed ZDV therapy (RR = 0.42, p = .02) and delayed versus late ZDV therapy (RR = 0.51; p = .0004). Duration of benefit was estimated to be 4.5 years (early versus delayed) and 1.7 years (delayed versus late). For patients with less rapid pre-ZDV decline in CD4 levels, a significant progression benefit was observed for delayed versus late therapy (RR = 0.50; p = .02). Duration of benefit in this subgroup was estimated to be 1.8 years. No significant benefit was found for early versus delayed treatment (RR = 1.12) in the less rapid pre-ZDV CD4 cell decline subgroup. Conclusions: Early treatment compared with delayed treatment was associated with a sizable reduction in HIV progression, but the duration of benefits was estimated to last only about 2 years. Delayed treatment compared with late treatment with ZDV was associated with substantial reduction of progression, but this reduction was also clearly limited in duration. Benefits on progression and mortality for the early treatment group were heavily dependent on the pre-ZDV CD4 slope. In the subgroup of patients with the most rapid pre-ZDV CD4 cell declines, the duration of benefit was much longer, possibly as long as 4 years. C1 Walter Reed Army Inst Res, Div Prevent Med, Washington, DC USA. USA, Med Dept Ctr & Sch, Clin Invest Regulatory Off, Ft Sam Houston, TX USA. Wilford Hall USAF Med Ctr, Dept Infect Dis, Lackland AFB, TX 78236 USA. USN, Natl Med Ctr, HIV Res Clin, Henry M Jackson Fdn, Bethesda, MD USA. Walter Reed Army Med Ctr, Dept Med, Infect Dis Serv, Washington, DC 20307 USA. Fitzsimons Army Med Ctr, Dept Clin Invest, Aurora, CO 80045 USA. Denver Hlth & Hosp, Denver Publ Hlth, Denver, CO USA. Walter Reed Army Inst Res, Div Retrovirol, Rockville, MD USA. USN, Med Res Inst, Bethesda, MD USA. RP Gardner, LI (reprint author), NIOSH, Div Safety Res, Anal & Field Evaluat Branch, 1095 Willowdale Rd, Morgantown, WV 26505 USA. RI Hendrix, Craig/G-4182-2014; OI Hendrix, Craig/0000-0002-5696-8665; /0000-0002-5704-8094 NR 25 TC 3 Z9 3 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 1077-9450 J9 J ACQ IMMUN DEF SYND JI J. Acquir. Immune Defic. Syndr. Hum. Retrovirol. PD APR 1 PY 1998 VL 17 IS 4 BP 345 EP 353 PG 9 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA ZC552 UT WOS:000072592000009 PM 9525436 ER PT J AU Raouf, RA Palazotto, A AF Raouf, RA Palazotto, A TI Dynamic instability of tires under asymmetric loads SO JOURNAL OF AEROSPACE ENGINEERING LA English DT Article AB This paper presents an analytical procedure for predicting instability loads of composite tires using a simplified tire model. The tire is modeled as a closed composite torus with geometric nonlinearities. The equations of motion of the torus are derived using differential geometry, and the Galerkin procedure is used to discretize the spatial domain. The resulting equations are nonlinear ordinary differential equations with constant coefficients. However, the special form of these equations allows their reduction to linear ordinary differential equations with periodic coefficients. The Floquet theory is then used to determine the stability characteristics of these equations under various loads and an impact velocity loading. The torus is studied in two reinforcement configurations and various fiber volume fractions, Both configurations show a threshold value for the applied load at which the stability of the periodic solution is lost in a catastrophic manner. Both reinforcement schemes shows the same optimum value for fiber volume fraction at which the instability load is maximum. C1 USN Acad, Dept Engn Mech, Annapolis, MD 21402 USA. USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 USA SN 0893-1321 J9 J AEROSPACE ENG JI J. Aerosp. Eng. PD APR PY 1998 VL 11 IS 2 BP 32 EP 36 DI 10.1061/(ASCE)0893-1321(1998)11:2(32) PG 5 WC Engineering, Aerospace; Engineering, Civil SC Engineering GA ZC857 UT WOS:000072626000003 ER PT J AU Ford, JK Smith, EM Weissbein, DA Gully, SM Salas, E AF Ford, JK Smith, EM Weissbein, DA Gully, SM Salas, E TI Relationships of goal orientation, metacognitive activity, and practice strategies with learning outcomes and transfer SO JOURNAL OF APPLIED PSYCHOLOGY LA English DT Article; Proceedings Paper CT 10th Annual Conference of the Society-for-Industrial-and-Organizational-Psychology CY MAY 20, 1995 CL ORLANDO, FLORIDA SP Soc Ind & Org Psychol ID SELF-EFFICACY; JOB KNOWLEDGE; MOTIVATION; PERFORMANCE; ACHIEVEMENT; SKILL; ACQUISITION; CLASSROOM; COGNITION; PARADIGMS AB A model of learning transfer that focused on the active role of the learner was developed and tested within a complex decision-making task. The study examined how individual differences, learning strategies, and training outcomes influenced transfer of learning to a more complex task. A sample of 93 undergraduate students participated in 2-day radar operations study. Hierarchical regression analysis results indicated that mastery orientation was positively related to metacognitive activity of the learner. Metacognitive activity was significantly related to knowledge acquisition, skilled performance at the end of training, and self-efficacy. All 3 of these training outcomes wore related to performance on the transfer task. Implications of these findings for research and practice are discussed. C1 Michigan State Univ, Dept Psychol, E Lansing, MI 48824 USA. AON Consulting, Grosse Point, MI USA. USN, Air Warfare Ctr, Orlando, FL USA. George Mason Univ, Dept Psychol, Fairfax, VA 22030 USA. RP Ford, JK (reprint author), Michigan State Univ, Dept Psychol, E Lansing, MI 48824 USA. EM fordjk@pilot.msu.edu RI Gully, Stanley/D-1302-2012; OI Gully, Stanley/0000-0003-4037-3883 NR 69 TC 228 Z9 236 U1 4 U2 59 PU AMER PSYCHOLOGICAL ASSOC PI WASHINGTON PA 750 FIRST ST NE, WASHINGTON, DC 20002-4242 USA SN 0021-9010 J9 J APPL PSYCHOL JI J. Appl. Psychol. PD APR PY 1998 VL 83 IS 2 BP 218 EP 233 DI 10.1037/0021-9010.83.2.218 PG 16 WC Psychology, Applied; Management SC Psychology; Business & Economics GA ZH908 UT WOS:000073159800007 ER PT J AU Gossard, EE Wolfe, DE Moran, KP Paulus, RA Anderson, KD Rogers, LT AF Gossard, EE Wolfe, DE Moran, KP Paulus, RA Anderson, KD Rogers, LT TI Measurement of clear-air gradients and turbulence properties with radar wind profilers SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID REFRACTIVE-INDEX; BOUNDARY-LAYER; TEMPERATURE; ATMOSPHERE; STABILITY; SPECTRUM; RASS AB An experiment comparing balloon and profiler observations was carried out to evaluate the capability of Doppler radar wind profilers to remotely measure useful meteorological quantities other than wind. The site chosen was in Southern California during a time of year when it offers a natural laboratory for investigating extreme contrasts in temperature and humidity. To evaluate the new capabilities, it was found that new and additional treatment of the radar data was necessary. For example, the adequacy of the usual radar wind observations obtained by editing the Doppler spectral moments was found to be very questionable for shortterm observations, so the authors extended the editing to the raw spectra, and substantial improvement was found. The advantages of the redundancy in five-beam systems are investigated and are also found to be very necessary to obtain the accuracy needed. A technique for minimizing the variances of the differences of the four redundant pairs of radials is described. The resulting improved vertical velocity estimates substantially improve the agreement between radio acoustic sounding system (RASS) temperature retrievals and balloon-measured temperatures. The ability of the profilers to measure turbulence intensity was rested, and the accuracy of techniques using the spectral width to measure turbulent dissipation rate when complicated spectra are present is examined. Two different techniques for optimizing the calculation of spectral width are compared and the errors assessed. One technique integrates over the uncontaminated range of the chosen spectral peak and then extrapolates a Gaussian function to infinity. The other method uses the slope of the log least squares best fit of the uncontaminated points to a Gaussian function. Profiler-measured length scales of wind and scalar quantities are measured and compared. Profiles of radar-measured gradients of refractive index are compared with gradients measured by balloon. It is shown how gradients of humidity can be calculated to about the same accuracy as refractive-index gradients by combining the temperature gradients from RASS with the refractive-index gradient observations from the radar. C1 Univ Colorado, Environm Technol Lab, NOAA, Cooperat Inst Res Environm Sci, Boulder, CO 80303 USA. NOAA ERL, Environm Technol Lab, Boulder, CO USA. USN, Command Control & Ocean Surveillance Ctr, San Diego, CA 92152 USA. RP Gossard, EE (reprint author), Univ Colorado, Environm Technol Lab, NOAA, Cooperat Inst Res Environm Sci, R-E-ET4,325 Broadway, Boulder, CO 80303 USA. EM egossard@etl.moaa.gov NR 54 TC 38 Z9 40 U1 1 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD APR PY 1998 VL 15 IS 2 BP 321 EP 342 DI 10.1175/1520-0426(1998)015<0321:MOCAGA>2.0.CO;2 PG 22 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA ZD426 UT WOS:000072684000001 ER PT J AU Adesida, I Gaskill, DK Melloch, MR Spencer, M AF Adesida, I Gaskill, DK Melloch, MR Spencer, M TI Special issue papers on III-V nitrides and silicon carbide - Foreword SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Editorial Material C1 Univ Illinois, Urbana, IL 61801 USA. Naval Res Lab, Washington, DC USA. Purdue Univ, W Lafayette, IN 47907 USA. Howard Univ, Washington, DC 20059 USA. RP Adesida, I (reprint author), Univ Illinois, Urbana, IL 61801 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD APR PY 1998 VL 27 IS 4 BP 159 EP 159 PG 1 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA ZJ744 UT WOS:000073248600001 ER PT J AU Kim, S Rhee, SJ Li, X Coleman, JJ Bishop, SG Klein, PB AF Kim, S Rhee, SJ Li, X Coleman, JJ Bishop, SG Klein, PB TI Excitation mechanisms of multiple Er3+ sites in Er-implanted GaN SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 39th Electronic Materials Conference (EMC) CY 1997 CL COLORADA STATE UNIV, FT COLLINS, COLORADO HO COLORADA STATE UNIV DE Er-implantation; GaN; photoluminescence ID ERBIUM; LUMINESCENCE; PHOTOLUMINESCENCE; SEMICONDUCTORS; SAPPHIRE AB Site-selective photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopies carried out at 6K on the similar to 1540 nm I-4(13/2) --> I-4(15/2) emissions of Er3+ in Er-implanted GaN have revealed the existence of four different Er3+ sites and associated PL spectra in this semiconductor. Three of these four sites are excited by below-gap, impurity-or defect-related absorption bands, with subsequent nonradiative energy transfer to the Er3+ 4f electrons; a fourth site is excited by direct Er3+ 4f shell absorption. PLE spectra obtained by selectively detecting Er3+ PL from each of the three sites pumped by broad below-gap absorption bands are compared with the PLE spectra of broad PL bands attributed to implantation damage-induced defects in the Er-implanted GaN. This comparison enables us to distinguish broad-band, below-gap optical excitation processes for Er3+ emission that are attributable to (1) absorption due to implantation damage-induced defects; (2) absorption due to defects or impurities characteristic of the as-grown GaN film; and (3) an Er-specific absorption band just below the band gap which may involve the formation of an Er-related isoelectronic trap. The two sites excited by impurity-or defect-related absorption bands are also strongly pumped by above-gap excitation, while the sites pumped by the Er-related trap and direct 4f shell absorption are not. This observation indicates that excitation of Er3+ luminescence in crystalline semiconductor hosts by either optical or electrical injection of electron-hole pairs is dominated by trap-mediated carrier capture and energy transfer processes. These trap-mediated processes may also control the thermal quenching of Er3+ emission in semiconductors. C1 Univ Illinois, Microelect Lab, Urbana, IL 61801 USA. USN, Res Lab, Washington, DC 20375 USA. RP Kim, S (reprint author), Univ Illinois, Microelect Lab, Urbana, IL 61801 USA. RI Coleman, James/C-9703-2011; Li, Xiuling/A-2240-2010 NR 19 TC 21 Z9 21 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD APR PY 1998 VL 27 IS 4 BP 246 EP 254 DI 10.1007/s11664-998-0395-6 PG 9 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA ZJ744 UT WOS:000073248600018 ER PT J AU Chutich, MJ Kaminski, EJ Miller, DA Lautenschlager, EP AF Chutich, MJ Kaminski, EJ Miller, DA Lautenschlager, EP TI Risk assessment of the toxicity of solvents of gutta-percha used in endodontic retreatment SO JOURNAL OF ENDODONTICS LA English DT Article ID CHLOROFORM; HALOTHANE; ALTERNATIVES; HEPATITIS AB Three randomly assigned groups of single-canaled extracted teeth obturated with gutta-percha were retreated using controlled application of one of three organic solvents: chloroform, xylene, or halothane, Two additional groups of teeth served as positive and negative controls, Residual volume of solvent expressed through the apical foramen during retreatment was determined by the difference of pretreatment and posttreatment weights of hermetically sealed receptacles attached to the root surface of the teeth, Results indicate that the amount of solvent that has been determined to have leached out through the apical foramen is several orders of magnitude below the permissible toxic dose, Thus, it is proposed that the use of any of the aforementioned solvents used in the retreatment of root canals would pose negligible risk to the patient. C1 Northwestern Univ, Sch Dent, Evanston, IL USA. USN, Dent Ctr, Jacksonville, FL USA. Northwestern Univ, Evanston Hosp, Sch Med, Dept Oral Pathol, Evanston, IL 60201 USA. Northwestern Univ, Dept Restorat Dent, Evanston, IL USA. Northwestern Univ, Sch Dent, Dept Biomat, Evanston, IL USA. RP Chutich, MJ (reprint author), 2056 Deer Run Trail, Jacksonville, FL 32246 USA. NR 19 TC 10 Z9 12 U1 0 U2 0 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 APR PY 1998 VL 24 IS 4 BP 213 EP 216 DI 10.1016/S0099-2399(98)80098-8 PG 4 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA ZE298 UT WOS:000072778200001 PM 9641120 ER PT J AU Zaita, AV Buley, G Karlsons, G AF Zaita, AV Buley, G Karlsons, G TI Performance deterioration modeling in aircraft gas turbine engines 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 Steady-state performance models can be used to evaluate a new engine's baseline performance. As a gas turbine accumulates operating time in the field, its performance deteriorates due to fouling, erosion, and wear. This paper presents the development of a model for predicting the performance deterioration of aircraft gas turbines. The model accounts for rotating component deterioration based on the aircraft mission profiles and environmental conditions and the engine's physical and design characteristics. The methodology uses data correlations combined with a stage stacking technique for the compressor and a tip rub model, along with data correlations for the turbine to determine the amount of performance deterioration. The performance deterioration model interfaces with the manufacturer's baseline engine simulation model in order to create a deteriorated performance model for that engine. C1 Adv Engn & Res Associates Inc, Technol Dev Div, Arlington, VA 22202 USA. USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. USN, Air Warfare Ctr, Div Aircraft, Patuxent River, MD 20670 USA. RP Zaita, AV (reprint author), Adv Engn & Res Associates Inc, Technol Dev Div, 2361 Jefferson Davis Hwy,Suite UL336, Arlington, VA 22202 USA. NR 11 TC 19 Z9 20 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 APR PY 1998 VL 120 IS 2 BP 344 EP 349 DI 10.1115/1.2818128 PG 6 WC Engineering, Mechanical SC Engineering GA ZM040 UT WOS:000073498700015 ER PT J AU Kosek, W McCarthy, DD Luzum, BJ AF Kosek, W McCarthy, DD Luzum, BJ TI Possible improvement of Earth orientation forecast using autocovariance prediction procedures SO JOURNAL OF GEODESY LA English DT Article DE earth rotation; prediction; autocovariance ID ATMOSPHERIC ANGULAR-MOMENTUM; POLAR MOTION; EXCITATION; LENGTH; PERIOD; FLUCTUATIONS; OSCILLATIONS; ROTATION AB Autocovariance prediction has been applied to attempt to improve polar motion and UTl-UTC predictions. The predicted polar motion is the sum of the least-squares extrapolation model based on the Chandler circle, annual and semiannual ellipses, and a bias fit to the past 3 years of observations and the autocovariance prediction of these extrapolation residuals computed after subtraction of this model from pole coordinate data. This prediction method has been applied also to the UTl-UTC data, from which all known predictable effects were removed, but the prediction error has not been reduced with respect to the error of the current prediction model. However, the results show the possibility of decreasing polar motion prediction errors by about 50% for different prediction lengths from 50 to 200 days with respect to the errors of the current prediction model. Because of irregular variations in polar motion and UTl-UTC, the accuracy of the autocovariance prediction does depend on the epoch of the prediction. To explain irregular variations in x, y pole coordinate data, time-variable spectra of the equatorial components of the effective atmospheric angular momentum, determined by the National Center for Environmental Prediction, were computed. These time-variable spectra maxima for oscillations with periods of 100-140 days, which occurred in 1985, 1988, and 1990 could be responsible for excitation of the irregular short-period variations in pole coordinate data. Additionally, time-variable coherence between geodetic and atmospheric excitation function was computed, and the coherence maxima coincide also with the greatest irregular variations in polar motion extrapolation residuals. C1 Polish Acad Sci, Space Res Ctr, PL-01237 Warsaw, Poland. USN Observ, Washington, DC 20392 USA. RP Kosek, W (reprint author), Polish Acad Sci, Space Res Ctr, PL-01237 Warsaw, Poland. RI Kosek, Wieslaw/E-1962-2017 NR 54 TC 22 Z9 27 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0949-7714 J9 J GEODESY JI J. Geodesy PD APR PY 1998 VL 72 IS 4 BP 189 EP 199 DI 10.1007/s001900050160 PG 11 WC Geochemistry & Geophysics; Remote Sensing SC Geochemistry & Geophysics; Remote Sensing GA ZL723 UT WOS:000073464000001 ER PT J AU Bleiberg, J Halpern, EL Reeves, D Daniel, JC AF Bleiberg, J Halpern, EL Reeves, D Daniel, JC TI Future directions for the neuropsychological assessment of sports concussion SO JOURNAL OF HEAD TRAUMA REHABILITATION LA English DT Article DE computerized neuropsychological testing; concussion; reaction time ID MILD HEAD-INJURY; REACTION-TIME; ATTENTION DEFICITS; PERFORMANCE AB This article argues in favor of using newly developed computerized, complex reaction time (RT)-based neuropsychological procedures for the study of sports-related concussion. Recent studies show that by using these complex RT procedures, significant differences between concussed and control samples can be observed. The magnitude of RT differences is 110 ms or less, levels that are not meaningfully measured with stopwatch-based procedures. RT-based procedures also have the advantage of permitting analysis of variability of RT, and several recent studies have shown that brain dysfunction is accompanied by erratic and inconsistent RT. A currently ongoing sports concussion study using measures of complex RT and variability of RT is described. C1 Natl Rehabil Hosp, Assist Technol Res Ctr, Psychol Serv, Medlant Res Inst, Washington, DC 20010 USA. Nutr Rehabil Ctr, Assist Technol Ctr, Psychol Serv, Washington, DC USA. Naval Med Ctr, Dept Clin Invest, San Diego, CA USA. USN, Med Ctr, Dept Pediat, San Diego, CA 92152 USA. RP Bleiberg, J (reprint author), Natl Rehabil Hosp, Assist Technol Res Ctr, Psychol Serv, Medlant Res Inst, 102 Irving St NW, Washington, DC 20010 USA. OI Bleiberg, Joseph/0000-0003-0867-5494 NR 19 TC 46 Z9 46 U1 1 U2 4 PU ASPEN PUBL INC PI FREDERICK PA 7201 MCKINNEY CIRCLE, FREDERICK, MD 21704 USA SN 0885-9701 J9 J HEAD TRAUMA REHAB JI J. Head Trauma Rehabil. PD APR PY 1998 VL 13 IS 2 BP 36 EP 44 PG 9 WC Clinical Neurology; Rehabilitation SC Neurosciences & Neurology; Rehabilitation GA ZF451 UT WOS:000072898800006 PM 9575255 ER PT J AU Southwood, S Sidney, J Kondo, A del Guercio, MF Appella, E Hoffman, S Kubo, RT Chesnut, RW Grey, HM Sette, A AF Southwood, S Sidney, J Kondo, A del Guercio, MF Appella, E Hoffman, S Kubo, RT Chesnut, RW Grey, HM Sette, A TI Several common HLA-DR types share largely overlapping peptide binding repertoires SO JOURNAL OF IMMUNOLOGY LA English DT Article ID CLASS-II MOLECULES; COMPLEX-CLASS-II; MELANOMA ANTIGEN GP100; T-LYMPHOCYTE RESPONSE; BASIC-PROTEIN PEPTIDE; HEPATITIS-C VIRUS; IMMUNOGENIC PEPTIDES; VACCINE DEVELOPMENT; MULTIPLE-SCLEROSIS; CELL RESPONSES AB The peptide binding specificities of HLA-DRB1*0401, DRB1*0101, and DRB1*0701 have been analyzed by the use of large collections of synthetic peptides corresponding to naturally occurring sequences. The results demonstrated that nearly all peptides binding to these DR molecules bear a motif characterized by a large aromatic or hydrophobic residue in position 1 (Y, F, W, L, I, V, M) and a small, noncharged residue in position 6 (S, T, C, A, P, V, I, L, M). In addition, allele-specific secondary effects and secondary anchors were defined, and these parameters were utilized to derive allele-specific motifs and algorithms. By the combined use of such algorithms, peptides capable of degenerate DRB1*0101, DRB1*0401, and DRB1*0701 binding were identified. Additional experiments utilizing a panel of quantitative assays specific for nine additional common DR molecules identified a large set of DR molecules, which includes at least the DRB1*0101, DRB1*0401, DRB1*0701, DRB5*0101, DRB1*1501, DRB1*0901, and DRB1*1302 allelic products, characterized by overlapping peptide-binding repertoires. These results have implications for understanding the molecular interactions involved in peptide-DR binding, as well as the genetic and structural basis of MHC polymorphism. These results also have potential practical implications for the development of epitope-based prophylactic and therapeutic vaccines. C1 Epimmune Inc, San Diego, CA 92121 USA. Takara, Otsu, Shiga, Japan. NCI, NIH, Bethesda, MD 20892 USA. USN, Med Res Inst, Malaria Program, Bethesda, MD 20889 USA. Cytel Corp, San Diego, CA 92121 USA. La Jolla Inst Allergy & Immunol, San Diego, CA 92121 USA. RP Sette, A (reprint author), Epimmune Inc, 6555 Nancy Ridge Rd,Suite 200, San Diego, CA 92121 USA. EM asette@epimmune.com FU NIAID NIH HHS [N01-AI-45241] NR 94 TC 400 Z9 412 U1 0 U2 6 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD APR 1 PY 1998 VL 160 IS 7 BP 3363 EP 3373 PG 11 WC Immunology SC Immunology GA ZD573 UT WOS:000072700100037 PM 9531296 ER PT J AU Broussard, PR Wall, MA Talvacchio, J AF Broussard, PR Wall, MA Talvacchio, J TI Structural characterization of YBa2Cu3O7-delta/Y2O3 composite films SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID MGO; Y2O3 AB Using 4-circle x-ray diffraction and transmission electron microscopy, we have studied the microstructure and in-plane orientation of the phases present in thin film composite mixtures of YBa2Cu3O7-delta and Y2O3. We see a high degree of in-plane orientation and have verified a previous prediction for the in-plane order of Y2BaCuO5 on (110) MgO. Transmission electron microscopy shows the composite films to be a mixture of two phases, with YBCO grain sizes of approximate to 1 mu m. We have also compared our observations of the in-plane order to the predictions of a modified near coincidence site lattice model. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Northrop Grumman Sci & Technol Ctr, Pittsburgh, PA 15235 USA. RP Broussard, PR (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 7 TC 3 Z9 3 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD APR PY 1998 VL 13 IS 4 BP 954 EP 958 DI 10.1557/JMR.1998.0133 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA ZQ823 UT WOS:000073906500034 ER PT J AU Saenz, AW AF Saenz, AW TI Lie-series approach to the evolution of resonant and nonresonant anharmonic oscillators in quantum mechanics SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Article AB version of a normal-form method of Kummer and Gompa, analogous to the Lie-series methods of classical mechanics, is used to rigorously construct uniform long-time approximations to the quantum evolution of a system of resonant or nonresonant anharmonic oscillators. The Hamiltonian H-epsilon governing the system is a self-adjoint operator in the Hilbert space H=L-2(R-nu) (nu greater than or equal to 2), given formally by H-0 + epsilon V. Here, H-0 denotes the Hamiltonian of nu one-dimensional simple harmonic oscillators and epsilon V their anharmonic coupling, epsilon greater than or equal to 0 being a small parameter and V an operator of multiplication by a smooth function of polynomial growth at infinity. We treat the case in which an arbitrary number rho greater than or equal to 1 of the frequencies of these oscillators are rationally independent, imposing a standard diophantine condition on the independent frequencies if rho greater than or equal to 2. Under these assumptions, stated precisely in the paper, an Nth-order approximant psi(N)(t,epsilon) to the exact solution psi(t,epsilon) of the Schrodinger equation id psi(t,epsilon)/dt = H(epsilon)psi(t, epsilon), satisfying the initial condition psi(0,epsilon) = psi(0), is constructed inductively, where the initial state psi(0) belongs to a family of smooth functions dense in H. The main result is that psi(N)(t,epsilon) differs in H-norm from psi(t,epsilon) by less than or equal to const epsilon(N+1)\t\ for t is an element of R and epsilon in an arbitrary compact interval [0,epsilon(0)]. This result is obtained by an approach simpler and quite different from that of Kummer and Gompa, and extends their work to oscillators with nonpolynomial couplings, under very general resonance conditions. (C) 1998 American Institute of Physics. [S0022-2488(98)01203-1]. C1 Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. USN, Res Lab, Washington, DC 20375 USA. RP Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. NR 29 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0022-2488 EI 1089-7658 J9 J MATH PHYS JI J. Math. Phys. PD APR PY 1998 VL 39 IS 4 BP 1887 EP 1909 PG 23 WC Physics, Mathematical SC Physics GA ZF218 UT WOS:000072875500009 ER PT J AU Symonds, CL AF Symonds, CL TI Pickett's charge in history and memory SO JOURNAL OF MILITARY HISTORY LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Symonds, CL (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SOC MILITARY HISTORY PI LEXINGTON PA C/O VIRGINIA MILITARY INST, GEORGE C MARSHALL LIBRARY, LEXINGTON, VA 24450-1600 USA SN 0899-3718 J9 J MILITARY HIST JI J. Mil. Hist. PD APR PY 1998 VL 62 IS 2 BP 404 EP 405 DI 10.2307/120740 PG 2 WC History SC History GA ZF818 UT WOS:000072936300024 ER PT J AU Merzbacher, CI Barker, JG Swider, KE Ryan, JV Bernstein, RA Rolison, DR AF Merzbacher, CI Barker, JG Swider, KE Ryan, JV Bernstein, RA Rolison, DR TI Characterization of multi-phase aerogels by contrast-marching SANS SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5th International Symposium on Aerogels CY SEP 08-10, 1997 CL MONTPELLIER, FRANCE SP Univ Montpellier, CNRS, Reg Languedoc Roussillon, Ctr Etud Commissariat Energie Atom Bruyeres Chatel, Ctr Etud Commissariat Energie Atom Vahrho DE small-angle neutron scattering (SANS); aerogel; oxidation; contrast matching ID ANGLE NEUTRON-SCATTERING; SILICA AEROGEL AB Contrast-matching small-angle neutron scattering (SANS) has been used to independently characterize the structures of two-phase aerogels consisting of a metal oxide supported on silica aerogel. Ru oxide was formed on silica aerogel by oxidation at 400 degrees C of ruthenocene, impregnated from the vapor phase, or Ru(III)acetylacetonate, impregnated via an acetone solution. Fe oxide was formed by vapor-phase impregnation of ferrocene, followed by reduction at 400 degrees C and exposure to ambient air. The Ru oxide forms particles several tens of nanometers in diameter in the aerogel mesopores. The Fe oxide forms a coating which mimics the structure of the support. The silica aerogel structure is not affected by the deposition and heat treatment processes. (C) 1998 Elsevier Science B.V. All rights reserved. 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 16 TC 9 Z9 9 U1 0 U2 6 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 APR PY 1998 VL 225 IS 1-3 BP 234 EP 238 DI 10.1016/S0022-3093(98)00044-1 PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY627 UT WOS:000074642600046 ER PT J AU Swider, KE Merzbacher, CI Hagans, PL Rolison, DR AF Swider, KE Merzbacher, CI Hagans, PL Rolison, DR TI Aerogels as a tool to study the electrical properties of ruthenium dioxide SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5th International Symposium on Aerogels CY SEP 08-10, 1997 CL MONTPELLIER, FRANCE SP Univ Montpellier, CNRS, Reg Languedoc Roussillon, Ctr Etud Commissariat Energie Atom Bruyeres Chatel, Ctr Etud Commissariat Energie Atom Vahrho DE aerogels; Ruthenium dioxide; conductivity ID VANADIUM AB RuO2 is a well-known oxidation catalyst for electrolytic generation of Cl-2. Although bulk RuO2 is a metallic conductor, studies of mixed-oxide aerogels containing RuO2 confirm that the surface of RuO2 is a hydrous oxide and a mixed conductor. Our previous work showed that at room temperature, protonic and electronic conductivity occurs in mixed phase aerogels of RuO2 + TiO2 (designated as (Ru-Ti)O-x). Impedance measurements up to 340 degrees C demonstrate that electron hopping and/or semiconduction also occurs in (Ru-Ti)O-x aerogels. Electron hopping may occur between Ru3+ and Ru4+ ions in the ruthenia, while n-type semiconduction may be introduced into the titania by Ru3+ defects. The multiplicity of charge-transfer mechanisms measured on the surfaces of RuO2-based aerogels is indicative of the complexity of the catalytic and electrocatalytic chemistry performed on RuO2. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rolison, DR (reprint author), USN, Res Lab, Code 6170, Washington, DC 20375 USA. NR 13 TC 21 Z9 21 U1 1 U2 7 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 APR PY 1998 VL 225 IS 1 BP 348 EP 352 DI 10.1016/S0022-3093(98)00136-7 PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY627 UT WOS:000074642600067 ER PT J AU Ranganathan, D Kurur, S Madhusudanan, KP Roy, R Karle, IL AF Ranganathan, D Kurur, S Madhusudanan, KP Roy, R Karle, IL TI Self-assembling bis-dendritic peptides: design, synthesis and characterization of oxalyl-linked bis-glutamyl peptides [Glu(n)(CO2Me)(n+1)-CO-](2); n=1, 3, 7 SO JOURNAL OF PEPTIDE RESEARCH LA English DT Article DE X-ray diffraction analysis; hydrogen bonded chiral tape; supramolecular aggregation; self-complementary hydrogen bonding ID ACID MELAMINE LATTICE; SOLID-STATE; MOLECULAR RECOGNITION; UNPROTECTED PEPTIDES; BUILDING-BLOCKS; DENDRIMERS; ARCHITECTURE; AGGREGATION AB Three generations of glutamic acid dendrons [Glu(n)(CO2Me)(n+1); n = 1, 3, 7] have been joined together head-to-head by an oxalyl unit to form highly sterically congested bis-Glu-dendritic peptides with gelling properties. The single crystal X-ray structure of the first generation bis-dendritic peptide showed an extended hydrogen-bonded chiral tape with modest nonlinear optical activity. (C) Munksgaard 1998. C1 CSIR, Reg Res Lab, Biomol Res Unit, Trivandrum 695019, Kerala, India. Cent Drug Res Inst, Lucknow 226001, Uttar 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 TVM, NIIST/E-5132-2012 OI TVM, NIIST/0000-0002-5814-466X FU PHS HHS [30902] NR 28 TC 15 Z9 16 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 1397-002X J9 J PEPT RES JI J. Pept. Res. PD APR PY 1998 VL 51 IS 4 BP 297 EP 302 PG 6 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA ZD406 UT WOS:000072682000006 PM 9560005 ER PT J AU Ovchinnikov, YN Wolf, SA Kresin, VZ AF Ovchinnikov, YN Wolf, SA Kresin, VZ TI Generation and detection of pairing bosons - A new method to determine the mechanism of superconductivity in the oxides SO JOURNAL OF SUPERCONDUCTIVITY LA English DT Article DE pairing mechanism; pairing boson AB We propose a new method to determine the coupling boson in the cuprate superconductors based on the generation and detection of the appropriate boson analogous to the experiments performed on the generation and detection of phonons by conventional BCS superconductors. The appropriate choice of substrate and junction detector will allow the unambiguous determination of the boson that is formed by the recombination of energy gap edge quasiparticles produced by excitations into the normal state of the cuprates. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. USN, Res Lab, Washington, DC 20375 USA. LD Landau Theoret Phys Inst, Moscow 11733V, Russia. RP Ovchinnikov, YN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Wolf, Stuart/A-7513-2009 NR 11 TC 1 Z9 1 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0896-1107 J9 J SUPERCOND JI J. Supercond. PD APR PY 1998 VL 11 IS 2 BP 323 EP 325 DI 10.1023/A:1022604622449 PG 3 WC Physics, Applied; Physics, Condensed Matter SC Physics GA ZW706 UT WOS:000074439300023 ER PT J AU Miller, SR Mondry, T Reed, JS Findley, A Johnstone, PAS AF Miller, SR Mondry, T Reed, JS Findley, A Johnstone, PAS TI Delayed cellulitis associated with conservative therapy for breast cancer SO JOURNAL OF SURGICAL ONCOLOGY LA English DT Article DE cellulitis; breast cancer; breast conservation therapy; lymphedema ID LYMPH-NODE DISSECTION; CARCINOMA; SURGERY AB Background and Objectives: Delayed breast cellulitis is an infrequently reported entity after conservation therapy for breast cancer. We describe our experience with this entity at Naval Medical Center, San Diego. Methods: Eight patients who presented with delayed cellulitis after wide local excision/axillary dissection and boast radiotherapy (RT) are presented. Their clinical characteristics and therapy are described and possible causative factors are analyzed. Results: The latency of breast cellulitis is variable after breast conservation therapy, although most cases in our experience and in the literature occur within a year post-RT. These infections are frequently refractory to a single course of antibiotics (n = 4 cases in our experience). Some patients suffer multiple episodes separated by months. Conclusions: Breast cancer patients are at risk for delayed cellulitis after conservative surgery and RT. The mechanism of such events probably involves lymph stasis, however, therapy is no different from the more frequently occurring cases of cellulitis presenting perioperatively. (C) 1998 Wiley -Liss, Inc. C1 USN, Med Ctr, Dept Clin Res, Breast Hlth Ctr, San Diego, CA 92134 USA. USN, Med Ctr, Div Surg Oncol, San Diego, CA 92152 USA. Univ Calif San Diego, Div Radiat Oncol, La Jolla, CA 92093 USA. RP Johnstone, PAS (reprint author), USN, Med Ctr, Dept Clin Res, Breast Hlth Ctr, San Diego, CA 92134 USA. NR 11 TC 15 Z9 15 U1 0 U2 8 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0022-4790 J9 J SURG ONCOL JI J. Surg. Oncol. PD APR PY 1998 VL 67 IS 4 BP 242 EP 245 DI 10.1002/(SICI)1096-9098(199804)67:4<242::AID-JSO6>3.0.CO;2-8 PG 4 WC Oncology; Surgery SC Oncology; Surgery GA ZK146 UT WOS:000073290000006 PM 9579371 ER PT J AU Norton, GV Novarini, JC AF Norton, GV Novarini, JC TI Enhancement of the total acoustic field due to the coupling effects from a rough sea surface and a bubble layer SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID WAVE-GUIDE PROPAGATION; SOUND-PROPAGATION; OCEAN-SURFACE; SCATTERING; MODEL; BACKSCATTER; EQUATION AB At wind speeds higher than a few meters per second, when breaking waves are present, the sea surface roughness is accompanied by an assemblage of microbubbles forming different structures or clouds, varying in range and in time. For simplicity, in terms of an average bubble population, the time and space varying assemblage of microbubbles is often assumed to be uniform and referred to as the subsurface bubble layer. Of fundamental importance is the role that this subsurface bubble layer may play in connection with scattering from a rough air/sea interface. The purpose of this paper is to determine the effect that the rough surface in the presence of this subsurface bubble layer has on the total field at low frequencies. Numerical calculations indicate that at low frequencies the bubble layer shifts the incident angle on the surface to steeper angles. In addition it was found that the enhancement of the total field is a consequence of scattering at the rough surface in the presence of the upper refracting bubble layer. An enhancement of approximately 40 dB with respect to the bubble-free medium was obtained very near the surface for a frequency of 400 Hz, with a nominal grazing angle of 20 deg, and a void fraction at the surface of 3.2 x 10(-5). The enhancement decreases to about 10-15 dB at 10 m below the surface, but is still significant at depth exceeding the bubbly region. For a void fraction at the surface of 3.1x10(-6) the enhancement is approximately 5 dB. (C) 1998 Acoustical Society of America. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Planning Syst Inc, Long Beach, MS 39560 USA. RP Norton, GV (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. NR 24 TC 6 Z9 6 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 APR PY 1998 VL 103 IS 4 BP 1836 EP 1844 DI 10.1121/1.421335 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZJ991 UT WOS:000073274100015 ER PT J AU Marcus, MH Sarkissian, A AF Marcus, MH Sarkissian, A TI Rib resonances present in the scattering response of a ribbed cylindrical shell SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID INFINITE AB The presence of ribs in an evacuated, finite cylindrical shell, placed in a fluid medium, produces highlights in its scattering response at certain resonant frequencies. These resonances are identified from the end-incident bistatic response of a ribbed cylindrical shell and are shown to be produced by the flexural vibrations of individual ribs satisfying the boundary conditions of an annular plate. C1 USN, Res Lab, Washington, DC 20375 USA. RP Marcus, MH (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 9 TC 3 Z9 3 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 APR PY 1998 VL 103 IS 4 BP 1864 EP 1866 DI 10.1121/1.421337 PG 3 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZJ991 UT WOS:000073274100018 ER PT J AU Bucaro, JA Romano, AJ Sarkissian, A Photiadis, DM Houston, BH AF Bucaro, JA Romano, AJ Sarkissian, A Photiadis, DM Houston, BH TI Local admittance model for acoustic scattering from a cylindrical shell with many internal oscillators SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB This paper considers whether local admittance fluctuations can explain the acoustic scattering from a submerged shell with many internal oscillators observed by Bucaro et al. [Proc. ASME, Noise Control and Acoustics Div., NCA 22, 87-92 (1996)] and Photiadis ct al. [J. Acoust. Sec. Am. 101, 895-899 (1997)]. The scattering is computed using a Helmholtz-based approach for a locally reacting surface whose admittance is affected by the random placement of internal oscillators. The predicted scattering patterns versus frequency and monostatic scattering angle are shown to agree with what is observed in the measured results. (C) 1998 Acoustical Society of America. C1 USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Landover, MD 20785 USA. RP Bucaro, JA (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 14 TC 8 Z9 8 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 APR PY 1998 VL 103 IS 4 BP 1867 EP 1873 DI 10.1121/1.421338 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZJ991 UT WOS:000073274100019 ER PT J AU Brook, I Frazier, EH Yeager, JK AF Brook, I Frazier, EH Yeager, JK TI Microbiology of infected eczema herpeticum SO JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY LA English DT Article ID ATOPIC-DERMATITIS; CHILDREN C1 USN Hosp, Dept Pediat, Bethesda, MD 20814 USA. USN Hosp, Dept Dermatol, Bethesda, MD 20814 USA. USN Hosp, Dept Lab Med, Bethesda, MD 20814 USA. RP Brook, I (reprint author), POB 70412, Chevy Chase, MD 20813 USA. NR 5 TC 13 Z9 14 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0190-9622 J9 J AM ACAD DERMATOL JI J. Am. Acad. Dermatol. PD APR PY 1998 VL 38 IS 4 BP 627 EP 629 DI 10.1016/S0190-9622(98)70130-6 PG 3 WC Dermatology SC Dermatology GA ZG324 UT WOS:000072990100018 PM 9555806 ER PT J AU Schmid, F Harris, DC AF Schmid, F Harris, DC TI Effects of crystal orientation and temperature on the strength of sapphire SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID ALPHA-AL2O3; GROWTH; MECHANISM; FRACTURE; SLIP AB The flexure and compressive strengths of sapphire are dependent on crystal orientation and temperature. Most notably, the c-axis compressive strength decreases below the tensile strength at temperatures >400 degrees C and falls to 2% of the room-temperature compressive strength at 800 degrees C. Loss of compressive strength complicates the interpretation of flexure tests. Four-point flexure specimens with no component of c-axis compression increase in strength at temperatures >500 degrees C; however, specimens that have c-axis compression decrease in strength. It has been observed that c-axis compression causes twinning on rhombohedral crystal planes. Intersection of twins on different rhombohedral planes causes fracture that leads to mechanical failure. C1 Crystal Syst, Salem, MA 01970 USA. USN, Air Warfare Ctr, Res & Technol Grp, Chem & Mat Branch, China Lake, CA 93555 USA. RP Schmid, F (reprint author), Crystal Syst, Salem, MA 01970 USA. NR 43 TC 60 Z9 63 U1 1 U2 13 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 APR PY 1998 VL 81 IS 4 BP 885 EP 893 PG 9 WC Materials Science, Ceramics SC Materials Science GA ZJ248 UT WOS:000073195000009 ER PT J AU Ranganathan, D Haridas, V Karle, IL AF Ranganathan, D Haridas, V Karle, IL TI Cystinophanes, a novel family of aromatic-bridged cystine cyclic peptides: Synthesis, crystal structure, molecular recognition, and conformational studies SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID BETA-SHEET CONFORMATION; HIGH-AFFINITY LIGANDS; DICARBOXYLIC-ACIDS; BINDING; DESIGN; RECEPTOR; ION; PEPTIDOMIMETICS; GPIIB/IIIA; NANOTUBES AB A novel family of aromatic-bridged cystine cyclic peptides (cystinophanes) has been synthesized by a single-step procedure involving condensation of 1,3 aromatic (Ph or Pyr unit) dicarbonyl dichloride with either the simple L-cystine dimethyl ester to provide cystinophanes of 26-, 39-, and 52-membered rings through 2+2, 3+3, and 4+4 cyclization, respectively, or with cystine bis-peptides (H2N-Xaa-Cyst-Xaa-NH2) leading to a variety of 1+1 cystine-based peptidocyclophanes. H-1 NMR and CD studies have shown these cystinophanes to adopt a beta-turn-like structure in solution. X-ray crystal structure of a representative member (3a) containing two aromatic rings has shown a collapsed ring conformation with a near parallel face-to-face orientation of aromatic rings--a feature also suggested by NMR studies. The propensity of cystinocyclophanes to adopt beta-turn-type conformation is attributed to the presence of S-S linkage and the need to maintain st near orthogonal value of its torsion angle. The potential of cystinophanes to serve as artificial receptors in molecular recognition and host-guest complexation studies has been demonstrated with 26-membered, pyridine-bridged macrocycle 3b, which binds (H-1 NMR) to a number of 1,omega-alkane dicarboxylic acids [(CH2)(n)(COOH)(2), n = 1, ..., 4] and shows maximum affinity (K-assoc= 3.69 x 10(2) M-1) and selectivity for glutaric acid (n = 3) dicarboxylate. Crystal parameters for 3a are as follows: C32H36N4O12S4 . H2O . 2C(4)H(8)O(2), space group P2(1)2(1)2(1) With a = 11.748(1)Angstrom, b = 17.317(1) Angstrom, and c = 24.306(2) Angstrom. C1 CSIR, Reg Res Lab, Biomol Res Unit, Trivandrum 695019, Kerala, 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 50 TC 60 Z9 64 U1 1 U2 12 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 APR 1 PY 1998 VL 120 IS 12 BP 2695 EP 2702 DI 10.1021/ja9734915 PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA ZF391 UT WOS:000072892800001 ER PT J AU Marquez, VE Ezzitouni, A Russ, P Siddiqui, MA Ford, H Feldman, RJ Mitsuya, H George, C Barchi, JJ AF Marquez, VE Ezzitouni, A Russ, P Siddiqui, MA Ford, H Feldman, RJ Mitsuya, H George, C Barchi, JJ TI HIV-1 reverse transcriptase can discriminate between two conformationally locked carbocyclic AZT triphosphate analogues SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID HUMAN-IMMUNODEFICIENCY-VIRUS; HEXOSE-NUCLEIC-ACIDS; NUCLEOSIDE ANALOGS; CRYSTAL-STRUCTURE; SUGAR RING; BIOLOGICAL-ACTIVITY; MOLECULAR-STRUCTURE; SYN CONFORMATION; NEPLANOCIN-C; HOMO-DNA AB It has been proposed that the preference of 3'-azido-3'-deoxythymidine (AZT) for the extreme E-3 (south) conformation, as observed in its X-ray structure, is responsible for its potent anti-HIV activity. However, it has also been suggested that the antipodal north conformation may be required for the strong interaction of AZT 5'-triphosphate with its target enzyme, HIV reverse transcriptase (RT). To resolve this issue, we have constructed two conformationally rigid carbocyclic analogues of AZT which are locked permanently into opposite E-2 (north) and E-3 (south) conformations in order to test the ability of the corresponding 5'-triphosphates to inhibit RT. The two isomeric carbocyclic analogues of AZT, (N)-methano-carba-AZT (1) and (S)-methano-carba-AZT (2), were constructed on a bicyclo[3.1.0]hexane template that exhibits a rigid pseudoboat conformation, capable of mimicking the furanose pucker in the classical north and south conformations that are characteristic of standard nucleosides. The unique conformational properties of 1 and 2 observed by both X-ray and solution NMR studies showed the existence of the same invariant conformations in solution and in the solid state. In addition, differences observed in the outcome of the Mitsunobu inversion of a secondary hydroxyl function attempted with both bicyclo[3.1.0]hexane nucleoside analogues could be explained by the rigid pseudoboat nature of this system. In one case, the bicyclic system facilitated formation of an anhydronucleoside intermediate, whereas in the other it completely prevented its formation. The chemically synthesized 5'-triphosphates of 1 and 2 were evaluated directly as RT inhibitors using both a recombinant enzyme and enzyme obtained and purified directly from wild-type viruses. The results showed that inhibition of RT occurred only with the conformationally locked E-2 (N)-methano-carba-AZT 5'-triphosphate. This inhibition was equipotent to and kinetically indistinguishable from that produced by AZT 5'-triphosphate. The antipodal E-3 (S)-methano-carba-AZT 5'-triphosphate, on the other hand, did not inhibit RT. C1 NCI, Med Chem Lab, Div Basic Sci, NIH, Bethesda, MD 20892 USA. NCI, Expt Retrovirol Sect, Med Branch, Div Clin Sci,NIH, Bethesda, MD 20892 USA. USN, Struct Matter Lab, Res Lab, Washington, DC 20375 USA. RP Marquez, VE (reprint author), NCI, Med Chem Lab, Div Basic Sci, NIH, Bethesda, MD 20892 USA. RI Barchi Jr., Joseph/N-3784-2014 NR 55 TC 142 Z9 145 U1 1 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 APR 1 PY 1998 VL 120 IS 12 BP 2780 EP 2789 DI 10.1021/ja973535+ PG 10 WC Chemistry, Multidisciplinary SC Chemistry GA ZF391 UT WOS:000072892800011 ER PT J AU Mansour, AN Melendres, CA Wong, J AF Mansour, AN Melendres, CA Wong, J TI In situ X-ray absorption spectroscopic study of electrodeposited nickel oxide films during redox reactions SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID MULTIPLE-SCATTERING CALCULATIONS; FINE-STRUCTURE; QUADRIVALENT NICKEL; EDGE STRUCTURE; SPECTRA; QUICK; EXAFS AB The quick-scanning extended X-ray absorption fine structure technique of X-ray absorption spectroscopy has been employed to monitor structural changes during the cyclic electrochemical oxidation and reduction of nickel oxide thin film electrodes. The films were prepared by anodic deposition onto a graphite substrate at 1.1 V vs. SCE from a solution of 0.05 M NiSO4 + 0.5 CH3COONa. The freshly "as-deposited" film contained mainly Ni2+ and Ni4+ with highly disordered structures. The phase containing Ni2+ can be charged in 1 M of KOH solution to a phase containing Ni4+. Electrochemical reduction of a charged nickel oxide film at constant current leads to the formation of a Ni(OH), which transforms to P-Ni(OH), with time in the KOH solution. The discharged film can be recharged to form a phase which contains mostly Ni4+. The fraction of Ni4+ in the film increased with charging time and reached a value of 0.8 (i.e., 80% of Ni is present as Ni4+) after 38 min of charging at a constant current of 1.68 mA/cm(2). The Ni4+ phase is structurally similar to that of a NiO2 phase produced by electrochemical oxidation of LiNiO2 in a nonaqueous electrolyte as has been shown previously. C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Mansour, AN (reprint author), USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. NR 29 TC 11 Z9 11 U1 2 U2 8 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 APR PY 1998 VL 145 IS 4 BP 1121 EP 1125 DI 10.1149/1.1838426 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZD712 UT WOS:000072715900016 ER PT J AU Park, YS AF Park, YS TI Current status of infrared detectors and focal plane arrays SO JOURNAL OF THE KOREAN PHYSICAL SOCIETY LA English DT Review ID CHEMICAL-VAPOR-DEPOSITION; MOLECULAR-BEAM EPITAXY; HIGH-QUALITY INSB; PHOTOCONDUCTANCE MEASUREMENTS; ROOM-TEMPERATURE; MU-M; WAVELENGTH; GROWTH; PHOTODETECTORS; GAAS AB In this article, some of the recent developments in infrared detectors and focal plane arrays are reviewed. Both thermal and photon detectors are compared and recent results are discussed. In photon detectors, several material systems, including II-VI, III-V and quantum wells are reviewed. Some of the new III-V material systems for infrared detectors are discussed in more detail with experimental results. Applications of the III-V material systems for uncooled photodetectors and focal plane arrays are also discussed. C1 Off Naval Res, Arlington, VA 22217 USA. RP Park, YS (reprint author), Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. NR 58 TC 5 Z9 6 U1 0 U2 0 PU KOREAN PHYSICAL SOC PI SEOUL PA 635-4, YUKSAM-DONG, KANGNAM-KU, SEOUL 135-703, SOUTH KOREA SN 0374-4884 J9 J KOREAN PHYS SOC JI J. Korean Phys. Soc. PD APR PY 1998 VL 32 IS 4 BP 443 EP 451 PG 9 WC Physics, Multidisciplinary SC Physics GA ZJ223 UT WOS:000073191800003 ER PT J AU Lewis, DJ Simpson, RL AF Lewis, DJ Simpson, RL TI Turbulence structure of heat transfer through a three-dimensional turbulent boundary layer SO JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER LA English DT Article ID WALL TURBULENCE AB The structure of turbulent heat transfer in the well-documented pressure-driven, three-dimensional turbulent boundary layer generated by a wing-body junction was studied experimentally using a constant-current resistance thermometer and a fast-response, thin-layered surface heat flux gauge. Simultaneous time-resolved surface heat nux and temperature profile measurements were taken in the spatially developing three-dimensional turbulent boundary layer upstream of the wing. Mean heat transfer was decreased by three dimensionality. Mean temperature profiles showed logarithmic behavior but did not collapse on a law-of-the-wall profile. Statistical and spectral analyses of the temperature fluctuations provide information on changes to the near-wall turbulent structures. The strength of ejections from the near-wall region was decreased by three dimensionality. Time-delayed correlations of the surface heat flux and now temperature revealed an initially linear turbulent wave front whose inclination angle increases with three dimensionality. Coherency between wall heat flux and temperature fluctuations in the outer boundary layer was decreased by three dimensionality. C1 Virginia Polytech Inst & State Univ, Dept Aerosp & Ocean Engn, Blacksburg, VA 24061 USA. RP Lewis, DJ (reprint author), USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. EM djlewis@nswc.navy.mil; simpson@aoe.vt.edu NR 27 TC 3 Z9 3 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0887-8722 J9 J THERMOPHYS HEAT TR JI J. Thermophys. Heat Transf. PD APR-JUN PY 1998 VL 12 IS 2 BP 248 EP 255 DI 10.2514/2.6328 PG 8 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA ZG837 UT WOS:000073045000016 ER PT J AU Coletta, JM Hemp, JR AF Coletta, JM Hemp, JR TI A serpentine and hypoplastic infrarenal aorta associated with aneurysm: A case report SO JOURNAL OF VASCULAR SURGERY LA English DT Article ID ATHEROSCLEROSIS C1 USN, Med Ctr, Dept Gen Surg, Div Vasc Surg, San Diego, CA 92134 USA. RP Coletta, JM (reprint author), USN, Med Ctr, Dept Gen Surg, Div Vasc Surg, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0741-5214 J9 J VASC SURG JI J. Vasc. Surg. PD APR PY 1998 VL 27 IS 4 BP 763 EP 766 DI 10.1016/S0741-5214(98)70247-2 PG 4 WC Surgery; Peripheral Vascular Disease SC Surgery; Cardiovascular System & Cardiology GA ZK806 UT WOS:000073365600026 PM 9576095 ER PT J AU Ridgway, SH Carder, DA AF Ridgway, SH Carder, DA TI Net-aided foraging by two white whales SO MARINE MAMMAL SCIENCE LA English DT Article C1 USN, Command Control & Ocean Surveillance Syst Ctr RDT, San Diego, CA 92152 USA. RP Ridgway, SH (reprint author), USN, Command Control & Ocean Surveillance Syst Ctr RDT, DIV D3503,Rm 200, San Diego, CA 92152 USA. NR 3 TC 2 Z9 3 U1 0 U2 0 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD APR PY 1998 VL 14 IS 2 BP 332 EP 334 DI 10.1111/j.1748-7692.1998.tb00723.x PG 3 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA ZG014 UT WOS:000072956100013 ER PT J AU Gao, M Feng, CR Wei, RP AF Gao, M Feng, CR Wei, RP TI An analytical electron microscopy study of constituent particles in commercial 7075-T6 and 2024-T3 alloys SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID PITTING CORROSION AB To better understand the role of constituent particles in pitting corrosion, analytical electron microscopic studies were performed on the constituent particles in commercial 7075-T6 and 2024-T3 alloys. Five phases, namely, Al23CuFe4 and amorphous SiO2 in 7075-T6 and Al2CuMg, Al2Cu, and (Fe,Mn)(x)Si(Al,Cu)(y) in 2024-T3, were identified. The crystal structure and chemistry of the Al23CuFe4, Al2CuMg, and Al2Cu phases in these alloys are in good agreement with the published data. Small deviations from their stoichiometric compositions were observed and are attributed to the influence of alloy composition on the phase chemistry. For the (Fe,Mn)(x)Si(Al,Cu)(y) (approximately, x = 3 and y = 11) phase, a rhombohedral structure, with lattice parameter a = b = c = 1.598 nm and alpha = beta = gamma = 75 deg, was identified and is believed to be a modified form of either Al8Fe2Si or Al10Mn3Si. Information from this study provided technical support for studying the electrochemical interactions between the individual particles (or phases) and the matrix. The corrosion results are reported in a companion article. C1 Mobil Explorat & Prod Ctr, Mat Corros & Inspect Grp, Farmers Branch, TX 75381 USA. USN, Res Lab, Div Sci Mat, Washington, DC 20375 USA. Lehigh Univ, Dept Mech Engn & Mech, Bethlehem, PA 18015 USA. RP Gao, M (reprint author), Mobil Explorat & Prod Ctr, Mat Corros & Inspect Grp, Farmers Branch, TX 75381 USA. NR 15 TC 103 Z9 111 U1 1 U2 31 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 APR PY 1998 VL 29 IS 4 BP 1145 EP 1151 DI 10.1007/s11661-998-0240-9 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZK623 UT WOS:000073343700001 ER PT J AU Merrill, LL Newell, CE Milner, JS Koss, MP Hervig, LK Gold, SR Rosswork, SG Thornton, SR AF Merrill, LL Newell, CE Milner, JS Koss, MP Hervig, LK Gold, SR Rosswork, SG Thornton, SR TI Prevalence of premilitary adult sexual victimization and aggression in a navy recruit sample SO MILITARY MEDICINE LA English DT Article ID CRIMINAL VICTIMIZATION; EXPERIENCES SURVEY; PHYSICAL ABUSE; RAPE; HEALTH; WOMEN; IMPACT; SCOPE; RISK; VIOLENCE AB U.S. Navy recruits (n = 3,776) were surveyed for premilitary histories of adult sexual assault. They completed a survey designed to estimate rates for experiences as victims (women) and perpetrators (men) of attempted and completed rape since the age of 14. The results show that 45.5% of the women reported being the victim of attempted (9.4%) or completed rape (36.1%) before entering the Navy, Male recruits' self-reports indicated that 14.8% admitted perpetrating attempted (3.5%) or completed rape (11.3%) before entering the Navy, A high percentage of recruits in this study reported histories of sexual assault, Female victims of sexual assault are at high risk of incurring somatic and/or psychological problems that require treatment by health care professionals, Male perpetrators of sexual assault are at high risk of repeating their behavior. The results of this study suggest that it may be cost-effective to develop treatment, education, and prevention programs for military recruits. C1 Naval Hlth Res Ctr, Med Informat Syst & Operat Res Dept, San Diego, CA 92186 USA. RP Merrill, LL (reprint author), Naval Hlth Res Ctr, Med Informat Syst & Operat Res Dept, POB 85122, San Diego, CA 92186 USA. NR 40 TC 47 Z9 47 U1 2 U2 3 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 APR PY 1998 VL 163 IS 4 BP 209 EP 212 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA ZG349 UT WOS:000072992700006 PM 9575763 ER PT J AU Rowe, JA Scragg, IG Kwiatkowski, D Ferguson, DJP Carucci, DJ Newbold, CI AF Rowe, JA Scragg, IG Kwiatkowski, D Ferguson, DJP Carucci, DJ Newbold, CI TI Implications of Mycoplasma contamination in Plasmodium falciparum cultures and methods for its detection and eradication SO MOLECULAR AND BIOCHEMICAL PARASITOLOGY LA English DT Article DE Plasmodium falciparum; mycoplasma; cell culture; 4-oxo-quinolone-3-carboxylic acid; rosette; tumour necrosis factor ID TUMOR-NECROSIS-FACTOR; CELL-CULTURES; PNEUMONIAE; INHIBITION C1 John Radcliffe Hosp, Inst Mol Med, Mol Parasitol Grp, Oxford OX3 9DS, England. John Radcliffe Hosp, Dept Paediat, Oxford OX3 9DU, England. John Radcliffe Hosp, Electron Microscopy Unit, Oxford OX3 9DU, England. USN, Med Res Inst, Rockville, MD 20852 USA. RP Rowe, JA (reprint author), John Radcliffe Hosp, Inst Mol Med, Mol Parasitol Grp, Oxford OX3 9DS, England. FU Wellcome Trust NR 15 TC 32 Z9 34 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-6851 J9 MOL BIOCHEM PARASIT JI Mol. Biochem. Parasitol. PD APR 1 PY 1998 VL 92 IS 1 BP 177 EP 180 DI 10.1016/S0166-6851(97)00237-5 PG 4 WC Biochemistry & Molecular Biology; Parasitology SC Biochemistry & Molecular Biology; Parasitology GA ZG201 UT WOS:000072977300016 PM 9574920 ER PT J AU Chow, GM Kurihara, LK AF Chow, GM Kurihara, LK TI Selected papers from the NATO Advanced Study Institute (ASI) on Nanostructured Materials - August 10-20, 1997, St. Petersburg, Russia - Preface SO NANOSTRUCTURED MATERIALS LA English DT Editorial Material C1 Potomac Res Int, Fairfax, VA 22030 USA. USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. RP Chow, GM (reprint author), Natl Univ Singapore, Dept Mat Sci, Kent Ridge, Singapore 119260, Singapore. NR 0 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0965-9773 J9 NANOSTRUCT MATER JI Nanostruct. Mater. PD APR PY 1998 VL 10 IS 3 BP U5 EP U5 PG 1 WC Materials Science, Multidisciplinary SC Materials Science GA 110UK UT WOS:000075398900001 ER PT J AU Washburn, AR AF Washburn, AR TI Branch and bound methods for a search problem SO NAVAL RESEARCH LOGISTICS LA English DT Article ID MOVING-TARGET; CONSTRAINED-PATH AB The problem of searching for randomly moving targets such as children and submarines is known to be fundamentally difficult, but finding efficient methods for generating optimal or near optimal solutions is nonetheless an important practical problem. This paper investigates the efficiency of Branch and Bound methods, with emphasis on the tradeoff between the accuracy of the bound employed and the time required to compute it. A variety of bounds are investigated, some of which are new. In most cases the best bounds turn out to be imprecise, but very easy to compute. (C) 1998 John Wiley & Sons, Inc. C1 USN, Postgrad Sch, Dept Operat Res, Monterey, CA 93943 USA. RP Washburn, AR (reprint author), USN, Postgrad Sch, Dept Operat Res, Monterey, CA 93943 USA. NR 15 TC 25 Z9 25 U1 1 U2 2 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 APR PY 1998 VL 45 IS 3 BP 243 EP 257 DI 10.1002/(SICI)1520-6750(199804)45:3<243::AID-NAV1>3.0.CO;2-7 PG 15 WC Operations Research & Management Science SC Operations Research & Management Science GA ZC573 UT WOS:000072594200001 ER PT J AU Lindsey, JW Prues, SL Alva, C Ritchie, GD Rossi, J AF Lindsey, JW Prues, SL Alva, C Ritchie, GD Rossi, J TI Trimethylolpropane phosphate (TMPP) perfusion into the nucleus accumbens of the rat: Electroencephalographic, behavioral and neurochemical correlates SO NEUROTOXICOLOGY LA English DT Article DE TMPP; bicyclophosphates; nucleus accumbens; seizures; GABA antagonist ID STRUCTURE-TOXICITY RELATIONSHIPS; EXTRACELLULAR DOPAMINE; GABA ANTAGONISTS; MICRODIALYSIS; SEIZURE; NOREPINEPHRINE; STIMULATION; PICROTOXIN; LUBRICANT; FOREBRAIN AB The infusion (0.13 mu mol/infusion) of the convulsant trimethylolpropane phosphate (TMPP) into the nucleus accumbens (NA) of adult Sprague-Dawley rats reliably induced subclinical seizures, hyperlocomotor activity, and integrated stereotypies. Observation of these behaviors was temporally correlated with the appearance of EEG paroxysms, as well as with significant decreases in extracellular concentrations of both dopamine (DA) and norepinephrine (NE) in the NA. Repeated perfusion of TMPP revealed significant increases in stereotypic behavior during subsequent pre-drug baseline testing. (C) 1998 Intox Press, Inc. C1 USN, Inst Med Res, Detachment Toxicol, Wright Patterson AFB, OH 45433 USA. Geo Ctr Inc, Wright Patterson AFB, OH 45433 USA. RP Lindsey, JW (reprint author), USN, Inst Med Res, Detachment Toxicol, 2612 5th St,Area B,Bldg 433, Wright Patterson AFB, OH 45433 USA. NR 43 TC 8 Z9 9 U1 0 U2 0 PU INTOX PRESS INC PI LITTLE ROCK PA PO BOX 24865, LITTLE ROCK, AR 72221 USA SN 0161-813X J9 NEUROTOXICOLOGY JI Neurotoxicology PD APR PY 1998 VL 19 IS 2 BP 215 EP 225 PG 11 WC Neurosciences; Pharmacology & Pharmacy; Toxicology SC Neurosciences & Neurology; Pharmacology & Pharmacy; Toxicology GA ZE075 UT WOS:000072755200005 PM 9553958 ER PT J AU Wang, HT Jansen, RW AF Wang, HT Jansen, RW TI Approximate evaluation of the distortion to the peak ocean wavelength and direction derived from SAR image spectra SO OCEAN ENGINEERING LA English DT Article ID SYNTHETIC-APERTURE-RADAR; SURFACE-WAVES; SIMULATION AB A calculation procedure using the modulation transfer function approach is presented to estimate the distortions to the values of the peak ocean wavelength and direction derived from SAR images of these waves. The distortions are calculated for ranges of SAR parameters which are typical for aircraft and satellites, and ocean wave parameters which reflect sea states which can be imaged by these SARs. The calculated distortions are discussed in terms of overall trends, effect of particular SAR and wave parameters, and qualitatively compared with observed differences between SAR and in situ measurements. (C) 1997 Elsevier Science Ltd. C1 NAVAL RES LAB,WASHINGTON,DC. NR 22 TC 2 Z9 2 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0029-8018 J9 OCEAN ENG JI Ocean Eng. PD APR-MAY PY 1998 VL 25 IS 4-5 BP 243 EP 259 DI 10.1016/S0029-8018(97)00010-3 PG 17 WC Engineering, Marine; Engineering, Civil; Engineering, Ocean; Oceanography SC Engineering; Oceanography GA YJ374 UT WOS:A1998YJ37400001 ER PT J AU Bill, A Wolf, SA Ovchinnikov, YN Kresin, VZ AF Bill, A Wolf, SA Ovchinnikov, YN Kresin, VZ TI Effect of magnetic impurity correlations on Josephson tunneling SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article DE Josephson effect; pair breaking ID SR-CU-O; CRITICAL-FIELD; NORMAL-STATE; SUPERCONDUCTORS; TEMPERATURE; DEPENDENCE AB The ordering trend of magnetic impurities at low temperature results in the frustration of the pair-breaking effect and induces a 'recovery' of superconducting properties. We show that this effect manifests itself in the deviation of the Josephson current amplitude from the values obtained within the Ambegaokar-Baratoff and the Abrikosov-Gor'kov models. We consider both weak and strong-coupling cases. The theory is applied to describe the experimental data obtained for the low-T-c superconductor SmRh4B4. We further predict a 'recovery' effect of the Josephson current in high-temperature superconductors. (C) 1998 Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. USN, Res Lab, Washington, DC 20375 USA. Russian Acad Sci, LD Landau Inst Theoret Phys, Moscow 11733V, Russia. RP Univ Calif Berkeley, Lawrence Berkeley Lab, MS 62-203,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Wolf, Stuart/A-7513-2009 NR 27 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD APR 1 PY 1998 VL 298 IS 3-4 BP 231 EP 239 DI 10.1016/S0921-4534(97)01813-3 PG 9 WC Physics, Applied SC Physics GA ZN320 UT WOS:000073634100010 ER PT J AU Gallet, JJ Mariot, JM Journel, L Hague, CF Kappler, JP Schmerber, G Singh, DJ Krill, G Goulon, J Rogalev, A AF Gallet, JJ Mariot, JM Journel, L Hague, CF Kappler, JP Schmerber, G Singh, DJ Krill, G Goulon, J Rogalev, A TI Rh 4d spin polarization of valence states in Co-Rh SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC CIRCULAR-DICHROISM; X-RAY-FLUORESCENCE; TRANSITION; FE; NI; EMISSION; ALLOYS AB X-ray fluorescence spectra involving Rh valence states in Co-Rh-based alloys have been recorded using circularly polarized photons from the Hellos II helical undulator at ESRF. Magnetic circular dichroism in the x-ray emission (XEMCD) is observed. To help identify the significance of the XEMCD signal, spin-polarized density functional electronic structure calculations for Co3Rh have been performed using the general potential linearized augmented plane wave method and appropriate transition matrix elements included to calculate spin-polarized spectra. The theoretical spin polarization is in excellent agreement with experiment inso far as both reveal that, at rhodium sites, polarization is concentrated close to the Fermi edge. The width of the peak in spin polarization can be varied by substituting Ru or Pd for Ph. The size of the change is discussed in relation to the measured magnetization and interpreted with the help of a generalized Slater-Pauling approach [A. R. Williams et al., IEEE Trans. Magn. MAG-19, 1983 (1983)]. C1 Univ Pierre & Marie Curie, Lab Chim Phys Mat & Rayonnement, URA 176, F-75231 Paris 05, France. Inst Phys & Chim Mat Strasbourg, UMR 46, Grp Etud Mat Met, F-69037 Strasbourg, France. USN, Res Lab, Washington, DC 20375 USA. MENSR, CEA, CNRS, Utilisat Rayonnement Electromagnet Lab, F-91405 Orsay, France. European Synchrotron Radiat Facil, F-38043 Grenoble, France. RP Gallet, JJ (reprint author), Univ Pierre & Marie Curie, Lab Chim Phys Mat & Rayonnement, URA 176, 11 Rue Pierre & Marie Curie, F-75231 Paris 05, France. RI Singh, David/I-2416-2012 NR 35 TC 9 Z9 9 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 APR 1 PY 1998 VL 57 IS 13 BP 7835 EP 7840 DI 10.1103/PhysRevB.57.7835 PG 6 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300067 ER PT J AU Muller, DA Singh, DJ Silcox, J AF Muller, DA Singh, DJ Silcox, J TI Connections between the electron-energy-loss spectra, the local electronic structure, and the physical properties of a material: A study of nickel aluminum alloys SO PHYSICAL REVIEW B LA English DT Review ID X-RAY-ABSORPTION; TRANSITION-METAL ALUMINIDES; DENSITY-OF-STATES; BOND-ORDER; BAND-STRUCTURE; INTERMETALLIC COMPOUNDS; MOMENTS DEVELOPMENTS; COHESIVE PROPERTIES; GRAIN-BOUNDARIES; B2 STRUCTURE AB The local electronic structure of a material can be determined from the energy-loss spectrum of a swift electron beam scattered through it. When the electron beam is focused down to the width of an atomic column, the electronic density of states (DOS) at an interface, grain boundary, or impurity site can be decomposed by site, chemical species and angular momentum. Here we discuss the use of electron-energy-loss spectroscopy (EELS) fine structure to provide insight into the origin of grain boundary and interfacial properties reported earlier [D. A. Muller et al., Phys. Rev. Lett. 75, 4744 (1995)] for Ni3Al. We examine the electronic structure trends in Ni-Al compounds, both experimentally with the EELS measurements and theoretically, using ab initio band-structure calculations. The conditions under which the band-structure calculations can quantitatively reproduce the EELS measurements (and in particular, the question of just which local DOS is being measured) are addressed. Cyrot-Lackmann's moments theorem provides a framework to explain the systematic changes in the local DOS on alloying. The shape changes in the near-edge fine structure of both the Ni and Al L edges are readily understood by the sensitivity of the fourth moment of the local DOS to the angular character of the Ni-Al bonding. The language of bond-order potentials proved useful in linking shape changes in the DOS to changes in cohesion. The consequences for formation energies and ordering trends in the transition-metal-aluminum alloys an also discussed. C1 Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14853 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. USN, Res Labs, Washington, DC 20375 USA. RP Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14853 USA. RI Singh, David/I-2416-2012; OI Muller, David/0000-0003-4129-0473 NR 109 TC 155 Z9 156 U1 4 U2 44 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 APR 1 PY 1998 VL 57 IS 14 BP 8181 EP 8202 DI 10.1103/PhysRevB.57.8181 PG 22 WC Physics, Condensed Matter SC Physics GA ZH083 UT WOS:000073070400029 ER PT J AU Soulen, RJ Fogle, WE AF Soulen, RJ Fogle, WE TI Low-temperature scales come under pressure - Reply SO PHYSICS TODAY LA English DT Letter C1 USN, Res Lab, Washington, DC 20375 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Soulen, RJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD APR PY 1998 VL 51 IS 4 BP 105 EP 105 PG 1 WC Physics, Multidisciplinary SC Physics GA ZF498 UT WOS:000072903500024 ER PT J AU Pecora, L AF Pecora, L TI Chaos starts to communicate SO PHYSICS WORLD LA English DT Article C1 USN, Res Lab, Washington, DC 20375 USA. RP Pecora, L (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD APR PY 1998 VL 11 IS 4 BP 25 EP 26 PG 2 WC Physics, Multidisciplinary SC Physics GA ZG076 UT WOS:000072963200026 ER PT J AU Darken, RP Allard, T Achille, LB AF Darken, RP Allard, T Achille, LB TI Spatial orientation and wayfinding in large-scale virtual spaces: An introduction SO PRESENCE-TELEOPERATORS AND VIRTUAL ENVIRONMENTS LA English DT Editorial Material ID ENVIRONMENTS; PERCEPTION; MEMORY C1 USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93940 USA. Off Naval Res, Cognit & Neural Sci & Technol Div, Arlington, VA 22217 USA. USN, Res Lab, Washington, DC 20222 USA. RP Darken, RP (reprint author), USN, Postgrad Sch, Dept Comp Sci, Monterey, CA 93940 USA. EM darken@cs.nps.navy.mil NR 23 TC 30 Z9 30 U1 1 U2 5 PU M I T PRESS PI CAMBRIDGE PA FIVE CAMBRIDGE CENTER, CAMBRIDGE, MA 02142 USA SN 1054-7460 J9 PRESENCE-TELEOP VIRT JI Presence-Teleoper. Virtual Env. PD APR PY 1998 VL 7 IS 2 BP 101 EP 107 DI 10.1162/105474698565604 PG 7 WC Computer Science, Cybernetics; Computer Science, Software Engineering SC Computer Science GA ZF951 UT WOS:000072949600001 ER PT J AU Cai, WJ Chu, PC AF Cai, WJ Chu, PC TI A thermal oscillation under a restorative forcing SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE interdecadal oscillations; restorative forcing; Rossby waves; thermal circulation ID GENERAL-CIRCULATION MODELS; INTERDECADAL VARIABILITY; THERMOHALINE CIRCULATION; PARAMETER SENSITIVITY; OCEAN-CLIMATE; HEAT-FLUX; DRIVEN; ADJUSTMENT; BASIN AB The authors report an interdecadal oscillation in a wind-and thermally-driven ocean general circulation model (OGCM). The oscillation is tantalizing in that it occurs under a relatively strong thermal damping (26.3 W m(-2) K-1). Examinations involving a two-dimensional OGCM, a simple thermal 'flipflop' model, and a three-dimensional OGCM with and without the nonlinear effect of temperature in the state equation of sea water demonstrate that the oscillation is not driven by mechanisms such as the so-called convective oscillator, or the advective overshooting oscillator. Instead, the oscillation is associated with the propagation of modelled long Rossby-waves with westward phase velocity. It is found that the north-south basin extent of the OGCM is an important factor; a larger north-south basin extent is conducive to the generation of thermal wind flows crucial for initiating the propagation of disturbances. The geophysical relevance of these results is discussed. C1 CSIRO, Div Atmospher Res, Aspendale, Vic 3195, Australia. Naval Postgrad Sch, Monterey, CA USA. RP Cai, WJ (reprint author), CSIRO, Div Atmospher Res, PMB1, Aspendale, Vic 3195, Australia. RI Cai, Wenju/C-2864-2012 NR 35 TC 1 Z9 1 U1 0 U2 0 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 APR PY 1998 VL 124 IS 547 BP 793 EP 809 DI 10.1256/smsqj.54706 PN A PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZK822 UT WOS:000073367200006 ER PT J AU Nagel, DJ AF Nagel, DJ TI The status of 'cold fusion' SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article ID ELECTROCHEMICAL-CELLS; EXCESS ENTHALPY; CALORIMETRY; FLEISCHMANN; DEUTERIUM; METALS; CLAIMS; WATER; BOIL AB The questions raised by reports of nuclear reactions at low energies, so called 'cold fusion', are not yet answered to the satisfaction of many scientists. Further experimental investigations of these and related questions seems desirable, at least for scientific if not practical reasons. Properly conducted, such investigations would be indistinguishable from normal research. They would yield information germane to accepted areas of scientific inquiry and technological utility. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 USN, Div Condensed Matter & Radiat Sci, Res Lab, Washington, DC 20375 USA. RP Nagel, DJ (reprint author), USN, Div Condensed Matter & Radiat Sci, Res Lab, Washington, DC 20375 USA. NR 49 TC 10 Z9 10 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD APR-JUN PY 1998 VL 51 IS 4-6 BP 653 EP 668 DI 10.1016/S0969-806X(97)00230-2 PG 16 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA ZU325 UT WOS:000074185400104 ER PT J AU Korzekwa, RA Grothaus, MG Hutcherson, RK Roush, RA Brown, R AF Korzekwa, RA Grothaus, MG Hutcherson, RK Roush, RA Brown, R TI Destruction of hazardous air pollutants using a fast rise time pulsed corona reactor SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID DISCHARGE AB Increasingly stringent environmental regulation imposed on both the military and civilian sectors has created a growing demand for alternative abatement methods for a variety of hazardous compounds. One alternative, the nonthermal plasma, shows promise of providing an efficient means for the destruction of dilute concentrations of hazardous air pollutants. The Dahlgren Laboratory of the Naval Surface Warfare Center has extensively investigated one type of nonthermal plasma discharge, the pulsed corona reactor, for the destruction of volatile organic compounds and chemical warfare agents. In this reactor, a fast rise time (similar to 10 ns), short duration (<100 ns), high-voltage pulse is repetitively delivered to a wire-cylinder electrode geometry, thereby producing a multitude of streamer discharges along its length. The resulting nonthermal plasma contains highly reactive chemical radicals which can interact with and destroy the hazardous molecules entrained in the ambient atmosphere flowing through the reactor volume. Increased electrical efficiency was obtained using a combination of high efficiency constant-current capacitor-charging high repetition-rate spark gap switching, and resonant energy transfer to the reactor. Promising results have been obtained for toluene, methylene chloride, and dichlorodifluoromethane in air at concentrations of a few hundred parts per million. The device has been operated at voltages up to 30 kV, pulse repetition rates up to 1.4 kHz, and flow rates up to 60 l/min. Detailed electrical measurements have been made to properly characterize the electrical properties of the pulsed corona reactor and to validate subsequent improvements in the reactor energy efficiency. (C) 1998 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. SW Res Inst, San Antonio, TX 78228 USA. OSRAM Sylvania Inc, Beverly, MA 01915 USA. Fed Bur Invest, Engn Res Facil, Quantico, VA 22135 USA. USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Korzekwa, RA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 18 TC 25 Z9 27 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD APR PY 1998 VL 69 IS 4 BP 1886 EP 1892 DI 10.1063/1.1148859 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA ZJ144 UT WOS:000073183900055 ER PT J AU Sanders, T AF Sanders, T TI V.O. Klyuchevskii, historian of Russia SO RUSSIAN REVIEW LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Sanders, T (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BLACKWELL PUBLISHERS PI MALDEN PA 350 MAIN STREET, STE 6, MALDEN, MA 02148 USA SN 0036-0341 J9 RUSS REV JI Russ. Rev. PD APR PY 1998 VL 57 IS 2 BP 299 EP 300 PG 2 WC History SC History GA ZD215 UT WOS:000072662900024 ER PT J AU Glenn, SM Haidvogel, DB Schofield, OME von Alt, CJ Levine, ER AF Glenn, SM Haidvogel, DB Schofield, OME von Alt, CJ Levine, ER TI Coastal predictive skill experiments SO SEA TECHNOLOGY LA English DT Article C1 Rutgers State Univ, Inst Marine & Coastal Sci, New Brunswick, NJ 08903 USA. Woods Hole Oceanog Inst, Ocean Syst Lab, Woods Hole, MA 02543 USA. USN, Undersea Warfare Ctr, Newport, RI USA. RP Glenn, SM (reprint author), Rutgers State Univ, Inst Marine & Coastal Sci, New Brunswick, NJ 08903 USA. NR 0 TC 18 Z9 18 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 APR PY 1998 VL 39 IS 4 BP 63 EP 69 PG 7 WC Engineering, Ocean SC Engineering GA ZK030 UT WOS:000073277900010 ER PT J AU Chang, CC Sirkis, JS AF Chang, CC Sirkis, JS TI Design of fiber optic sensor systems for low velocity impact detection SO SMART MATERIALS & STRUCTURES LA English DT Article ID DEMODULATION; TEMPERATURE; DAMAGE; STRAIN AB This paper describes the design and development of promising optical fiber sensor systems for low velocity impact detection and impact-induced damage assessment. The sensor systems were based on the combination of path-matched differential interferometry (PMDI), in-line fiber etalon (ILFE) sensors and specifically designed analog phase trackers. The four demodulators investigated include: (1) the phase generated carrier (PGC) with differential-cross-multiplier (DCM) implemented electronically; (2) the PGC with DCM but where the final integration in the DCM is carried out numerically; (3) the single-channel phase tracker; and (4) the sin(Delta phi)/cos(Delta phi) phase tracker. Careful consideration is given to an impact sensor system design methodology that considers potential optical sensor configurations, dynamic range and bandwidth of demodulation systems, optical phase-strain relationships, and the mechanical interaction of the optical fiber with its host structure. initial impact tests using aluminium plates with surface-mounted ILFE sensors were performed to investigate the capability of the four given demodulators. The single-channel and sin(Delta phi)/cos(Delta phi) phase trackers proved to be most suitable for the present impact application, and therefore they were utilized in the low velocity impact tests using graphite/epoxy composite plates with embedded ILFE sensors. C1 Univ Maryland, Smart Mat & Struct Res Ctr, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. NR 29 TC 13 Z9 13 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0964-1726 J9 SMART MATER STRUCT JI Smart Mater. Struct. PD APR PY 1998 VL 7 IS 2 BP 166 EP 177 DI 10.1088/0964-1726/7/2/004 PG 12 WC Instruments & Instrumentation; Materials Science, Multidisciplinary SC Instruments & Instrumentation; Materials Science GA ZL936 UT WOS:000073488400004 ER PT J AU Jones, RT Bellemore, DG Berkoff, TA Sirkis, JS Davis, MA Putnam, MA Friebele, EJ Kersey, AD AF Jones, RT Bellemore, DG Berkoff, TA Sirkis, JS Davis, MA Putnam, MA Friebele, EJ Kersey, AD TI Determination of cantilever plate shapes using wavelength division multiplexed fiber Bragg grating sensors and a least-squares strain-fitting algorithm SO SMART MATERIALS & STRUCTURES LA English DT Article ID SYSTEM AB An algorithm has been developed to determine the full deformation field of a cantilever honeycomb plate under arbitrary loading conditions. The algorithm utilizes strain information from a set of sixteen fiber Bragg grating sensors mounted on the plate so that all sensors measure strains along the clamped-free direction. The sensors were interrogated using a wavelength division multiplexing scheme. A two-dimensional polynomial function which represents the strain field was created using a least-squares surface-fitting algorithm. This function was integrated twice with the known boundary conditions applied to yield the deformation field for the plate. Finite-element comparisons were performed to test the accuracy of the strain-displacement algorithm. Single-point loading tests were also experimentally performed to further verify the accuracy of the algorithm. C1 Univ Maryland, Smart Mat & Struct Res Ctr, College Pk, MD 20742 USA. USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 15 TC 31 Z9 33 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0964-1726 J9 SMART MATER STRUCT JI Smart Mater. Struct. PD APR PY 1998 VL 7 IS 2 BP 178 EP 188 DI 10.1088/0964-1726/7/2/005 PG 11 WC Instruments & Instrumentation; Materials Science, Multidisciplinary SC Instruments & Instrumentation; Materials Science GA ZL936 UT WOS:000073488400005 ER PT J AU Idriss, RL Kodindouma, MB Kersey, AD Davis, MA AF Idriss, RL Kodindouma, MB Kersey, AD Davis, MA TI Multiplexed Bragg grating optical fiber sensors for damage evaluation in highway bridges SO SMART MATERIALS & STRUCTURES LA English DT Article AB A multiplexed Bragg grating optical fiber monitoring system is designed and integrated at the construction stage in an experimental full scale laboratory bridge. The test bridge is a 40 ft span non-composite steel girder concrete deck bridge. The network of sensors is used to measure the strain throughout the bridge, with sensors bonded to the tension steel in the slab and attached to the bottom flange of the girders. Resistive strain gages and Bragg grating sensors are placed side by side to compare results. The strain data are obtained for the pristine structure, then damage is introduced at midspan for an exterior girder. Several levels of damage in the form of cuts in one of the girders are imposed with the final cut resulting in a half depth fracture of the girder. The load path in the structure is obtained using the built in sensor system. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. New Mexico State Univ, Las Cruces, NM 88003 USA. NR 4 TC 51 Z9 57 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0964-1726 J9 SMART MATER STRUCT JI Smart Mater. Struct. PD APR PY 1998 VL 7 IS 2 BP 209 EP 216 DI 10.1088/0964-1726/7/2/008 PG 8 WC Instruments & Instrumentation; Materials Science, Multidisciplinary SC Instruments & Instrumentation; Materials Science GA ZL936 UT WOS:000073488400008 ER PT J AU Buoncristiani, AM McCullen, G Shin, AY Bathgate, B Akbarnia, BA AF Buoncristiani, AM McCullen, G Shin, AY Bathgate, B Akbarnia, BA TI An unusual cause of low back pain - Osteomyelitis of the spinous process SO SPINE LA English DT Article DE magnetic resonance imaging; osteomyelitis; spinous process osteomyelitis AB Study Design. A case report of osteomyelitis of the spinous process. Objective. To describe the diagnosis and successful treatment of a patient with spinous process osteomyelitis. Summary of Background Data. Spinous process osteomyelitis is exceedingly rare and may be misdiagnosed as paraspinal muscle strain, discitis, or vertebral body osteomyelitis. The clinical presentation of spinous process osteomyelitis is subtle, laboratory findings are nonspecific, and radiographs are often normal. Methods. The diagnosis, treatment, and outcome of two patients with spinous process osteomyelitis (an adult and a child) with insidious, nonspecific lumbar pain and fever are reviewed. Results. Magnetic resonance imaging with and without gadolinium enhancement demonstrated increased signal of the spinous process with paraspinous musculature enhancement, a finding consistent with spinous process osteomyelitis. Biopsy results demonstrated the presence of staphylococcus aureus in the child and no organisms in the adult. Treatment with intravenous antibiotics l led to resolution in both cases. Conclusions. The use of magnetic resonance imaging: technology permitted the early and accurate diagnosis of spinous process osteomyelitis. C1 USN, Med Ctr, Dept Orthopaed Surg, San Diego, CA 92152 USA. San Diego Ctr Spinal Disorders, San Diego, CA USA. RP McCullen, G (reprint author), USN, Med Ctr, Dept Orthopaed, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. OI Shin, Alexander/0000-0001-9658-8192 NR 11 TC 2 Z9 2 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0362-2436 J9 SPINE JI SPINE PD APR 1 PY 1998 VL 23 IS 7 BP 839 EP 841 DI 10.1097/00007632-199804010-00022 PG 3 WC Clinical Neurology; Orthopedics SC Neurosciences & Neurology; Orthopedics GA ZF625 UT WOS:000072915800022 PM 9563117 ER PT J AU Wen, H Wiesler, DG Tveten, A Danver, B Dandridge, A AF Wen, H Wiesler, DG Tveten, A Danver, B Dandridge, A TI High-sensitivity fiber-optic ultrasound sensors for medical imaging applications SO ULTRASONIC IMAGING LA English DT Article DE electromagnetic interference; laser interferometer; optical fiber; ultrasound sensor AB This paper presents several designs of high-sensitivity, compact fiber-optic ultrasound sensors that may be used for medical imaging applications. These sensors translate ultrasonic pulses into strains in single-mode optical fibers, which are measured with fiber-based laser interferometers at high precision. The sensors are simpler and less expensive to make than piezoelectric sensors, and are not susceptible to electromagnetic interference. It is possible to make focal sensors with these designs, and several schemes are discussed. Because of the minimum bending radius of optical fibers, the designs are suitable for single element sensors rather than for arrays. C1 NHLBI, Cardiac Energet Lab, NIH, Bethesda, MD 20892 USA. USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Wen, H (reprint author), NHLBI, Cardiac Energet Lab, NIH, Bethesda, MD 20892 USA. RI Wen, Han/G-3081-2010 OI Wen, Han/0000-0001-6844-2997 FU Intramural NIH HHS [Z01 HL004606-12] NR 8 TC 9 Z9 9 U1 0 U2 3 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0161-7346 J9 ULTRASONIC IMAGING JI Ultrason. Imaging PD APR PY 1998 VL 20 IS 2 BP 103 EP 112 PG 10 WC Acoustics; Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 104GL UT WOS:000075006300002 PM 9691368 ER PT J AU Lee, GF Hartmann, B AF Lee, GF Hartmann, B TI Specific damping capacity for arbitrary loss angle SO JOURNAL OF SOUND AND VIBRATION LA English DT Article AB An analysis was performed to establish a relationship between specific damping capacity and loss angle for materials with arbitrary loss angle. The motivation for this work is that the usual relationship is only valid for law loss materials and leads to some confusion when the specific damping capacity is greater than one. In this paper, two equations for specific damping capacity are derived that are valid for all values of loss angle. One equation uses the usual definition of specific damping capacity as dissipated energy per cycle divided by maximum stored energy. The other equation defines specific damping capacity as dissipated energy per cycle divided by work done per cycle. The latter equation has the desirable property of varying between zero and one. The analysis done in the time domain is extended to include analysis of hysteresis curves as well. (C) 1998 Academic Press Limited. C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. RP Lee, GF (reprint author), USN, Ctr Surface Warfare, Carderock Div, 9500 MacArthur Blvd, W Bethesda, MD 20817 USA. NR 11 TC 7 Z9 7 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD MAR 26 PY 1998 VL 211 IS 2 BP 265 EP 272 DI 10.1006/jsvi.1997.1387 PG 8 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA ZG303 UT WOS:000072987500008 ER PT J AU Wallace, MR Chamberlin, CJ Olson, PE Arvin, AM AF Wallace, MR Chamberlin, CJ Olson, PE Arvin, AM TI Varicella infection in adults reporting prior varicella - Reply SO JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION LA English DT Letter ID SUSCEPTIBILITY; SEROSURVEY; RECRUITS C1 USN, Med Ctr, San Diego, CA 92152 USA. Stanford Univ, Stanford, CA 94305 USA. RP Wallace, MR (reprint author), USN, Med Ctr, San Diego, CA 92152 USA. NR 4 TC 0 Z9 0 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 MAR 25 PY 1998 VL 279 IS 12 BP 912 EP 912 PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA ZC304 UT WOS:000072563600025 ER PT J AU Ayers, JD Harris, VG Sprague, JA Elam, WT Jones, HN AF Ayers, JD Harris, VG Sprague, JA Elam, WT Jones, HN TI On the formation of nanocrystals in the soft magnetic alloy Fe73.5Nb3Cu1Si13.5B9 SO ACTA MATERIALIA LA English DT Article ID ULTRAFINE GRAIN-STRUCTURE; ABSORPTION FINE-STRUCTURE; HIGH SATURATION MAGNETIZATION; FE-ZR-B; ATOM-PROBE; CU; CRYSTALLIZATION; COPPER; EXAFS; FE73.5CU1NB3SI13.5B9 AB Studies were conducted on alloys of atomic mass composition Fe73.5Nb3Cu1Si13.5B9 and Fe76.5Cu1Si13.5B9 TEM studies demonstrated that Fe-rich nanocrystals precipitated from the amorphous starting materials exhibited the DO, structure from very early in the transformation process. This result was corroborated by extended X-ray absorption fines structure (EXAFS) studies which showed evidence of ordering in the Fe-rich precipitates from early in the transformation process. EXAFS studies also showed that Cu clusters with near-f.c.c. structure were present from very early stages of the crystallization process. A model is proposed which describes the role of the Cu clusters as catalyzing nucleation of the DO3 crystallites by providing a low energy interface upon which the activation energy for nucleation of the DO3 phase is lowered. (C) 1998 Acta Metallurgica Inc. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ayers, JD (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Harris, Vincent/A-8337-2009 NR 31 TC 104 Z9 116 U1 4 U2 19 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 MAR 23 PY 1998 VL 46 IS 6 BP 1861 EP 1874 DI 10.1016/S1359-6454(97)00436-9 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZF480 UT WOS:000072901700003 ER PT J AU Lee, RL AF Lee, RL TI Digital imaging of clear-sky polarization SO APPLIED OPTICS LA English DT Article; Proceedings Paper CT Topical Meeting on Light and Color in the Open Air CY FEB 09-12, 1997 CL SANTA FE, NEW MEXICO ID LIGHT; MODEL AB If digital images of clear daytime or twilight skies are acquired through a linear polarizing filter, they can be combined to produce high-resolution maps of skylight polarization. Here polarization P and normalized Stokes parameter Q are measured near sunset at one inland and two coastal sites. Maps that include the principal plane consistently show that the familiar Arago and Babinet neutral points are part of broader areas in which skylight polarization is often indistinguishably different from zero. A simple multiple-scattering model helps explain some of these polarization patterns. (C) 1998 Optical Society of America. C1 USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. RP Lee, RL (reprint author), USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. NR 25 TC 35 Z9 39 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 MAR 20 PY 1998 VL 37 IS 9 BP 1465 EP 1476 DI 10.1364/AO.37.001465 PG 12 WC Optics SC Optics GA ZB681 UT WOS:000072496900008 PM 18268737 ER PT J AU Lee, RL AF Lee, RL TI Mie theory, Airy theory, and the natural rainbow SO APPLIED OPTICS LA English DT Article; Proceedings Paper CT Topical Meeting on Light and Color in the Open Air CY FEB 09-12, 1997 CL SANTA FE, NEW MEXICO AB Compared with Mie scattering theory, Airy rainbow theory clearly miscalculates some monochromatic details of scattering by small water drops. Yet when monodisperse Airy theory is measured by perceptual (rather than purely physical) standards such as chromaticity and luminance contrast, it differs very little from Mie theory. Considering only the angular positions of luminance extrema, Airy theory's errors are largest for small droplets such as those that dominate cloudbows and fogbows. However, integrating over a realistic drop-size distribution for these bows eliminates most perceptible color and luminance differences between the two theories. (C) 1998 Optical Society of America. C1 USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. RP Lee, RL (reprint author), USN Acad, Dept Oceanog, Annapolis, MD 21402 USA. NR 23 TC 44 Z9 44 U1 1 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 MAR 20 PY 1998 VL 37 IS 9 BP 1506 EP 1519 DI 10.1364/AO.37.001506 PG 14 WC Optics SC Optics GA ZB681 UT WOS:000072496900013 PM 18268742 ER PT J AU Pronko, MS Deniz, AV Yun, V Leng, YZ Goldhar, J AF Pronko, MS Deniz, AV Yun, V Leng, YZ Goldhar, J TI Subnanosecond switching, plasma electrode Pockels cell for high-contrast imaging with partially coherent light SO APPLIED OPTICS LA English DT Article ID PERFORMANCE; LASERS AB A high-contrast optical switch for imaging partially coherent light (similar to 150 times the diffraction limit) requires that it have a large angular acceptance. We describe the development of a high-speed Pockels cell that uses a thin crystal to simultaneously achieve high-contrast (greater than 1800:1) and large-angular acceptance (greater than 7 mrad for a 5-mm aperture). A KD*P crystal was used in a longitudinal-mode configuration with plasma discharges forming low-resistance, high optical transmission electrodes to couple the switching voltage. Rise times of the switched optical pulse of the order of 500 ps were observed. Characterization of the device in the near and far fields was also performed. (C) 1998 Optical Society of America. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. Fus Lighting Inc, Rockville, MD 20855 USA. RP Pronko, MS (reprint author), Fibertek, 510 Herndon Pkwy, Herndon, VA 22070 USA. NR 13 TC 1 Z9 1 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 MAR 20 PY 1998 VL 37 IS 9 BP 1659 EP 1665 DI 10.1364/AO.37.001659 PG 7 WC Optics SC Optics GA ZB681 UT WOS:000072496900036 PM 18268764 ER PT J AU Clegg, AW Fey, AL Lazio, TJW AF Clegg, AW Fey, AL Lazio, TJW TI The Gaussian plasma lens in astrophysics: Refraction SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM, general; plasmas; radiative transfer ID EXTREME SCATTERING EVENTS; BL LACERTAE OBJECTS; ANISOTROPIC MAGNETOGASDYNAMIC TURBULENCE; INTERSTELLAR-MEDIUM; DENSITY-FLUCTUATIONS; 5 GHZ; MODEL AB We present the geometrical optics for refraction of a distant background radio source by an interstellar plasma lens, with specific application to a lens with a Gaussian profile of free-electron column density. The refractive properties of the lens are specified completely by a dimensionless parameter alpha, which is a function of the wavelength of observation, the free-electron column density through the lens, the lens-observer distance, and the diameter of the lens transverse to the line of sight. A lens passing between the observer and a background source, due to the relative motions of the observer, lens, and source, produces modulations in the light curve of the background source. Because plasma lenses are diverging, the light curve displays a minimum in the background source's flux density, formed when the lens is on-axis, surrounded by enhancements above the nominal (unlensed) flux density. The exact form of the light curve depends only upon the parameter alpha and the relative angular sizes of the source and lens as seen by the observer. Other effects due to lensing include the following: (1) the formation of caustic surfaces, upon which the apparent brightness of the background source becomes very large; (2) the possible creation of multiple images of the background source; and (3) angular position wander of the background source. If caustics are formed, the separation of the outer caustics can be used to constrain a, while the separation of the inner caustics can constrain the size of the lens. We apply our analysis to two sources, which have undergone extreme scattering events: (1) 0954+658, a source for which we can identify multiple caustics in its light curve, and (2) 1741-038, for which polarization observations were obtained during and after the scattering event. We find general agreement between modeled and observed light curves at 2.25 GHz, but poor agreement at 8.1 GHz. The discrepancies between the modeled and observed light curves may result from some combination of substructure within the lens, an anisotropic lens shape, a lens which only grazes the source rather than passing completely over it, or unresolved substructure within the extragalactic sources. Our analysis also allows us to place constraints on the physical characteristics of the lens. The inferred properties of the lens responsible for the scattering event toward 0954+ 658 (1741-038) are that it was 0.38 AU (0.065 AU) in diameter with a peak column density of 0.24 pc cm(-3) (10(-4) pc cm(-3)), an electron density-within the lens of 10(5) cm(-3) (300 cm(-3)), and a mass of 6.5 x 10(-14) M-. (10(-18) M-.). The angular position wander caused by the lens was 250 mas (0.4 mas) at 2.25 GHz. In the case of 1741-038, we can place an upper limit of only 100 mG on the magnetic field within the lens. C1 USN, Res Lab, Washington, DC 20375 USA. USN Observ, Washington, DC 20392 USA. RP Millimeter Wave Report, POB 4749, Arlington, VA 22204 USA. EM clegg@intrepid.nrl.navy.mil; afey@alf.usno.navy.mil; lazio@rsd.nrl.navy.mil NR 25 TC 44 Z9 44 U1 1 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 1998 VL 496 IS 1 BP 253 EP 266 DI 10.1086/305344 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE341 UT WOS:000072782900023 ER PT J AU Hajian, AR Armstrong, JT Hummel, CA Benson, JA Mozurkewich, D Pauls, TA Hutter, DJ Elias, NM Johnston, KJ Rickard, LJ White, NM AF Hajian, AR Armstrong, JT Hummel, CA Benson, JA Mozurkewich, D Pauls, TA Hutter, DJ Elias, NM Johnston, KJ Rickard, LJ White, NM TI Direct confirmation of stellar limb darkening with the Navy Prototype Optical Interferometer SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars, fundamental parameters; techniques, interferometric ID ANGULAR DIAMETER MEASUREMENTS; STARS AB Using three elements of the Navy Prototype Optical Interferometer and observing in 20 spectral channels covering 520-850 nm, we have implemented a phase bootstrapping technique in which short baselines with high visibilities are used to keep the longer baselines with low visibilities in phase. Using this method, we have been able to extend the spatial frequency coverage beyond the first zero of the stellar visibility function for two K giants alpha Arietis, and alpha Cassiopeiae. The data are inconsistent with a uniform-disk model and confirm the presence of limb-darkened radial profiles. Adopting a particular limb-darkening law enables us to determine the diameter with small formal errors (one part in 1000). In addition, we have measured closure phases for both stars. The closure phases show a jump of 180 degrees at the first zero in the visibility amplitude, which was expected. C1 USN Observ, Washington, DC 20392 USA. USN, Remote Sensing Div, Res Lab, Washington, DC 20375 USA. Univ Space Res Assoc, Washington, DC 20024 USA. USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. Lowell Observ, Flagstaff, AZ 86001 USA. RP USN Observ, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. EM hajian@fornax.usno.navy.mil; tarmstr@fornax.usno.navy.mil; cah@fornax.usno.navy.mil; jbenson@nofs.navy.mil; mozurk@rsd.nrl.navy.mil; pauls@atlas.nrl.navy.mil; djh@fornax.usno.navy.mil; nme@sextans.lowell.edu; kjj@astro.usno.navy.mil; rickard@rira.nrl.navy.mil; nmw@lowell.edu NR 23 TC 55 Z9 55 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 MAR 20 PY 1998 VL 496 IS 1 BP 484 EP 489 DI 10.1086/305388 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE341 UT WOS:000072782900041 ER PT J AU Armstrong, JT Mozurkewich, D Rickard, LJ Hutter, DJ Benson, JA Bowers, PF Elias, NM Hummel, CA Johnston, KJ Buscher, DF Clark, JH Ha, L Ling, LC White, NM Simon, RS AF Armstrong, JT Mozurkewich, D Rickard, LJ Hutter, DJ Benson, JA Bowers, PF Elias, NM Hummel, CA Johnston, KJ Buscher, DF Clark, JH Ha, L Ling, LC White, NM Simon, RS TI The Navy Prototype Optical Interferometer SO ASTROPHYSICAL JOURNAL LA English DT Article DE instrumentation, interferometers; techniques, interferometric ID III STELLAR INTERFEROMETER; ANGULAR DIAMETER MEASUREMENTS; MODE FIBER OPTICS; SEEING MEASUREMENTS; ASTROMETRY; ARRAY; STARS; BETELGEUSE; TRACKING; ENVELOPE AB We describe the Navy Prototype Optical Interferometer (NPOI), a joint project of the Naval Research Laboratory (NRL) and the US Naval Observatory (USNO) in cooperation with Lowell Observatory. The NPOI has recently begun operations at the Lowell Observatory site near Flagstaff, Arizona, obtaining its first images, of a binary star, in 1996 May and June and its first limb-darkening observations during 1996 November to 1997 February. This paper gives an overview of the NPOI, including the characteristics of optical interferometry that affect its design. The NPOI includes subarrays for imaging and for astrometry. The imaging subarray consists of six moveable 50 cm siderostats feeding 12 cm apertures, with baseline lengths from 2.0 to 437 m. The astrometric subarray consists of four fixed 50 cm siderostats feeding 12 cm apertures (35 cm apertures to be installed in 1998), with baseline lengths from 19 m to 38 m. The shared back end covers 450-850 nm in 32 channels. The NPOI features vacuum feed and delay systems, active group-delay fringe tracking, and a high degree of automation. The astrometric subarray also includes an extensive site laser metrology system to measure the motions of the siderostats with respect to one another and to the bedrock. For imaging stellar surfaces, arrays with equal spacing between elements are superior to arrays that have been laid out to optimize (u, v) coverage and that therefore have unequal spacing. The imaging subarray of the NPOI provides a number of equally spaced configurations with linear scales at ratios of approximate to 1.64. Unequally spaced configurations are available for a variety of other imaging programs. Coherence across either type of imaging configuration is maintained by "phase bootstrapping": the phases on the longest baselines, on which fringes may be too weak to track, are stabilized by tracking fringes on the shortest baselines. In principle, the four elements of the astrometric subarray provide enough independent baselines to solve for stellar positions and the array geometry simultaneously while observing each of 11 stars only once. The anticipated magnitude limit is 7 mag or better with 12 cm apertures and average seeing; with 35 cm apertures, we expect the limit to be one or more magnitudes fainter. The anticipated wide-angle astrometric precision of the NPOI is approximate to 2 mas. The best angular resolution of the imaging subarray will be approximate to 200 mu as. Our experience with the Mark III interferometer suggests that we will be able to measure stellar diameters as small as 200 mu as with 1% precision and binary star separations as small as rho approximate to 65 mu as (for Delta m approximate to 0 mag) or rho approximate to 200 mu as (for Delta m approximate to 3-4 mag). With its large bandwidth and phase bootstrapping, the imaging subarray should be able to make images greater than or similar to 10 resolution elements across the disks of nearby late-type stars. C1 USN Observ, Dept Astron AD5, NRL USNO Opt Interferometer Project, Washington, DC 20392 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Space Res Assoc, Washington, DC 20024 USA. Photon Ind & Technol Dev Assoc, Taipei, Taiwan. Lowell Observ, Flagstaff, AZ 86001 USA. Natl Radio Astron Observ, Charlottesville, VA 22903 USA. Appl Res Corp, Landover, MD 20785 USA. Interferometr Inc, Vienna, VA 22182 USA. RP Armstrong, JT (reprint author), USN Observ, Dept Astron AD5, NRL USNO Opt Interferometer Project, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. NR 70 TC 242 Z9 245 U1 1 U2 6 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 MAR 20 PY 1998 VL 496 IS 1 BP 550 EP + DI 10.1086/305365 PN 1 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE341 UT WOS:000072782900047 ER PT J AU Levine, SE Sparke, LS AF Levine, SE Sparke, LS TI A model for lopsided galactic disks SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, evolution; galaxies, irregular; galaxies, kinematics and dynamics; galaxies, structure ID BARRED GALAXIES; DOUBLE NUCLEUS; SPIRAL GALAXY; INSTABILITIES; NGC-4027; IMAGES; SEARCH; GAS; M31 AB Many disk galaxies are lopsided; their brightest inner parts are displaced from the center of the outer isophotes or the outer contours of the H I disk. This asymmetry is particularly common in small, low-luminosity galaxies. We argue here that long-lived lopsidedness is a consequence of the disk lying off-center in the potential of the galaxy's extended dark halo and spinning in a sense retrograde to its orbit about the halo center. The stellar velocity field predicted by our gravitational N-body simulations is clearly asymmetric. C1 Univ Nacl Autonoma Mexico, IA, Observ Astron Nacl, Mexico City, DF, Mexico. USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. RP Levine, SE (reprint author), Univ Nacl Autonoma Mexico, IA, Observ Astron Nacl, Mexico City, DF, Mexico. NR 46 TC 43 Z9 43 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 MAR 20 PY 1998 VL 496 IS 1 BP L13 EP L16 DI 10.1086/311239 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE343 UT WOS:000072783100004 ER PT J AU Handwerger, BS Blair, PJ Sztein, MB Storrer, CE June, CH AF Handwerger, BS Blair, PJ Sztein, MB Storrer, CE June, CH TI T cells from aged mice have a defect in their ability to upregulate Bcl-x(L) following CD28 costimulation. SO FASEB JOURNAL LA English DT Meeting Abstract C1 USN, Med Res Inst, Bethesda, MD 20889 USA. Univ Maryland, Sch Med, Baltimore, MD 21201 USA. VA Med Ctr, Baltimore, MD 21201 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 20 PY 1998 VL 12 IS 5 SU S MA 5405 BP A933 EP A933 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HD UT WOS:000076006501786 ER PT J AU Witte, PL Stephan, R Lill-Elghanian, D Gray, K Saha, B AF Witte, PL Stephan, R Lill-Elghanian, D Gray, K Saha, B TI Expression of CD28 by bone marrow stromal cells. SO FASEB JOURNAL LA English DT Meeting Abstract C1 Loyola Univ, Med Ctr, Maywood, IL 60153 USA. USN, Med Res Inst, Bethesda, MD 20814 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 20 PY 1998 VL 12 IS 5 SU S MA 6205 BP A1072 EP A1072 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HD UT WOS:000076006502588 ER PT J AU Carslaw, KS Wirth, M Tsias, A Luo, BP Dornbrack, A Leutbecher, M Volkert, H Renger, W Bacmeister, JT Peter, T AF Carslaw, KS Wirth, M Tsias, A Luo, BP Dornbrack, A Leutbecher, M Volkert, H Renger, W Bacmeister, JT Peter, T TI Particle microphysics and chemistry in remotely observed mountain polar stratospheric clouds SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID INDUCED ICE PARTICLES; SULFURIC-ACID; GRAVITY-WAVES; TEMPERATURE-FLUCTUATIONS; MESOSCALE VARIABILITY; ARCTIC STRATOSPHERE; DROPLETS; MODEL; SIMULATION; EXCITATION AB Polar stratospheric clouds (PSCs) at 22-26 km were observed over the Norwegian mountains by airborne lidar on January 15, 1995. Simulations using a mesoscale model reveal that they were caused by mountain-induced gravity waves. The clouds had a highly detailed filamentary structure with bands as thin as 100 m in the vertical, and moved insignificantly over 4 hours, suggesting them to be quasi-stationary. The aircraft flight path was parallel or close to parallel with the wind at cloud level. Such a quasi-Lagrangian observation, together with the presence of distinct aerosol layers, allows an air parcel trajectory through the cloud to be constructed and enables the lidar images to be simulated using a microphysical box model and light scattering calculations. The results yield detailed information about particle evolution in PSCs and suggest that water ice nucleated directly from liquid HNO3/H2SO4/H2O droplets as much as 4 K below the ice frost point. The observation of solid nitric acid hydrate particles downwind of the mountains shows that such mesoscale events can generate solid PSC particles that can persist on: the synoptic scale. We also draw attention to the possible role of mesoscale PSCs in chlorine activation and subsequent ozone destruction. C1 Max Planck Inst Chem, D-55020 Mainz, Germany. USN, Res Lab, Washington, DC 20375 USA. Deutsch Forsch Anstalt Luft & Raumfahrt, Oberpfaffenhofen, Germany. RP Carslaw, KS (reprint author), Max Planck Inst Chem, Postfach 3060, D-55020 Mainz, Germany. EM carslaw@mpch-mainz.mpg.de; Martin.Wirth@dlr.de; tsias@mpch-mainz.mpg.de; pa2o@atlas.op.dlr.de; M.Leutbecher@dlr.de; Hans.Volkert@dlr.de; Wolfgang.Renger@dlr.de; julio@ismap5.nrl.navy.mil; peter@nike.mpch-mainz.mpg.de RI Volkert, Hans/A-7041-2013; Carslaw, Ken/C-8514-2009 OI Volkert, Hans/0000-0003-1688-208X; Carslaw, Ken/0000-0002-6800-154X NR 43 TC 129 Z9 130 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 20 PY 1998 VL 103 IS D5 BP 5785 EP 5796 DI 10.1029/97JD03626 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZC819 UT WOS:000072621300012 ER PT J AU Glaser, R Adin, I Shiftan, D Shi, Q Deutsch, HM George, C Wu, KM Froimowitz, M AF Glaser, R Adin, I Shiftan, D Shi, Q Deutsch, HM George, C Wu, KM Froimowitz, M TI Solution and solid-state conformational and structural analysis of the N-methyl derivatives of (+/-)-threo-methylphenidate, (+/-)-erythro-methylphenidate, and (+/-)-threo-p-methyl-methylphenidate hydrochloride salts SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID DOPAMINE REUPTAKE BLOCKERS; COUPLING-CONSTANTS; ANALGESIC DRUG; ANOREXIC DRUG; STEREOCHEMISTRY; METHYLPHENIDATE; DIASTEREOMERS; HYDROBROMIDE; COCAINE; NEFOPAM AB The conformational preferences of N-methyl derivatives of the dopamine reuptake blocker threo-methylphenidate [Ritalin] and the p-methyl analogue were determined in the solid state and in solution and that of the erythro isomer in solution. The solid-state structures of(+/-)-threo-N-methyl-alpha-phenyl-2-piperidineacetic acid methyl ester hydrochloride [(+/-)-threo-N-methyl-methylphenidate hydrochloride] (2) and (+/-)-threo-N,p-dimethyl-alpha-phenyl-2-piperidineacetic acid methyl ester hydrochloride (5) were determined by single crystal X-ray diffraction analysis. (+/-)-2 underwent spontaneous resolution to give crystalline chiral plates containing two independent molecules in the asymmetric ring, and at each site there is a disorder involving the N-methylpiperidinyl ring methylene and methyl carbon atoms with a 0.710(7):0.290(7) ratio of occupancy factors. The two (2RS,3RS,4SR) major disordered molecules have similar structures consisting of a chair conformation for the piperidine ring with axial N-methyl and CH(Ph)COOMe groups. The two (2RS,3RS,4RS) minor molecules in the disorder also have similar structures and differ from the major ones by epimerization at nitrogen and inversion of the piperidine ring to afford an axial N-methyl group, and an equatorial CH(Ph)COOMe group. (+/-)-5 gave crystalline plates also containing diaxially disposed piperidinyl-ring substituents. Dissolution in D2O of either 2 or its erythro-epimer (3) each gives a 5:4 ratio of two species in which the major species exhibits an axial N-methyl group and an equatorial CH(Ph)COOMe group while the minor species has a diequatorial arrangement for both substituents. Both of the axial N-methyl three or erythro major species in D2O are overwhelmingly conformationally biased in favor of an antiperiplanar H(2)... H(3) disposition and one piperidine ring invertomer. Dissolution of the three or erythro epimers in CD2Cl2 gives the same axial N-methyl/equaterial CH(Ph)COOMe and diequatorially disposed species but now in a reversed ratio [respectively 3:20 for three and 4:5 for erythro]. C1 Ben Gurion Univ Negev, Dept Chem, IL-84105 Beer Sheva, Israel. Hebrew Univ Jerusalem, Inst Adv Studies, IL-91904 Jerusalem, Israel. Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. Pharm Eco Labs, Lexington, MA 02173 USA. RP Glaser, R (reprint author), Ben Gurion Univ Negev, Dept Chem, IL-84105 Beer Sheva, Israel. NR 39 TC 18 Z9 18 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD MAR 20 PY 1998 VL 63 IS 6 BP 1785 EP 1794 DI 10.1021/jo971063b PG 10 WC Chemistry, Organic SC Chemistry GA ZD932 UT WOS:000072740000009 ER PT J AU Vu, TT Orazi, RJ McLandrich, MN AF Vu, TT Orazi, RJ McLandrich, MN TI Four channel fused fibre mux/demux couplers and add/drop filters in the 1300 and 1550nm regions SO ELECTRONICS LETTERS LA English DT Article ID FIBER AB Cascaded fused fibre devices designed to multiplex four channels in a wavelength band are described. These devices, capable of performing multiplexing, demultiplexing, or add/drop functions, show low insertion loss, high isolation, and polarisation independent operation. C1 USN, Space & Warfare Syst Ctr, San Diego, CA 92152 USA. RP Vu, TT (reprint author), USN, Space & Warfare Syst Ctr, Code D895,53560 Hull St, San Diego, CA 92152 USA. NR 4 TC 3 Z9 3 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 MAR 19 PY 1998 VL 34 IS 6 BP 583 EP 585 DI 10.1049/el:19980401 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA ZG121 UT WOS:000072967600056 ER PT J AU Chao, W Askew, EW Roberts, DE Wood, SM Perkins, JB AF Chao, W Askew, EW Roberts, DE Wood, SM Perkins, JB TI The effect of vitamin supplementation on indices of oxidative stress in urine, blood, and breath during strenuous cold weather work at moderate altitude. SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Utah, Salt Lake City, UT 84112 USA. USN, Hlth Res Ctr, San Diego, CA 92816 USA. Geocenters Inc, San Diego, CA 92816 USA. Ross Labs, Columbus, OH 43219 USA. Data Chem Div, Salt Lake City, UT 84123 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 17 PY 1998 VL 12 IS 4 SU S MA 3249 BP A560 EP A560 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HC UT WOS:000076006403244 ER PT J AU Kayar, SR Parker, EC Aukhert, EO AF Kayar, SR Parker, EC Aukhert, EO TI T-wave amplitude and oxygen pulse in guinea pigs is hyperbaric helium and hydrogen. SO FASEB JOURNAL LA English DT Meeting Abstract C1 USN, Med Res Inst, Bethesda, MD 20889 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 17 PY 1998 VL 12 IS 4 SU S MA 592 BP A102 EP A102 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HC UT WOS:000076006400592 ER PT J AU Vaitkevicius, H Farrow, S Lockette, W AF Vaitkevicius, H Farrow, S Lockette, W TI Racial differences in carbonic anhydrase esterase activity may contribute to the ethnic differences in titratable acid and calcium excretion. SO FASEB JOURNAL LA English DT Meeting Abstract C1 USN, Special Warfare Command, San Diego, CA 92152 USA. Wayne State Univ, Sch Med, Detroit, MI USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 17 PY 1998 VL 12 IS 4 SU S MA 2950 BP A507 EP A507 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HC UT WOS:000076006402945 ER PT J AU Kang, JU Frankel, MY Esman, RD Thompson, DA Robinson, BJ AF Kang, JU Frankel, MY Esman, RD Thompson, DA Robinson, BJ TI InGaAsP grown by He-plasma-assisted molecular beam epitaxy for 1.55 mu m high speed photodetectors SO APPLIED PHYSICS LETTERS LA English DT Article AB Simple photoconductive optical detectors for 1.55 mu m wavelength have been fabricated on InGaAsP grown by He-plasma assisted molecular beam epitaxy. Characterization of the photodetectors shows that their speed is determined by the free carrier trapping time, with a full width at half-maximum impulse response of approximately 6 ps. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. McMaster Univ, Ctr Electrophoton Mat & Devices, Hamilton, ON L8S 4L7, Canada. RP Kang, JU (reprint author), USN, Res Lab, Div Opt Sci, Code 5672, Washington, DC 20375 USA. RI Kang, Jin/A-3228-2010 NR 8 TC 1 Z9 1 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 MAR 16 PY 1998 VL 72 IS 11 BP 1278 EP 1280 DI 10.1063/1.121046 PG 3 WC Physics, Applied SC Physics GA ZC326 UT WOS:000072566000006 ER PT J AU Jacobs, GA Preller, RH Riedlinger, SK Teague, WJ AF Jacobs, GA Preller, RH Riedlinger, SK Teague, WJ TI Coastal wave generation in the Bohai Bay and propagation along the Chinese coast SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The Bohai Bay and Yellow Sea experience sea surface height (SSH) changes of 20 cm and larger during wintertime northerly and southerly wind bursts that have a time scale of a few days. These large SSH changes give rise to coastal shelf waves that subsequently propagate southward along the Chinese coast. Two models provide observations of these waves. The first one is a statistical model based on four years of TOPEX/POSEIDON altimeter SSH observations and Navy Operational Global Atmospheric Prediction System (NOGAPS) wind stress fields. The second model is a numerical model forced by the wind stress. The numerical model provides an objective interpretation of the wind stress response based on dynamical equations. The statistical model is based on observations with a linear response to the wind forcing and thus complements the numerical model. The observed waves closely resemble gravest mode shelf waves derived by analytical solutions. 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. NR 16 TC 11 Z9 12 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAR 15 PY 1998 VL 25 IS 6 BP 777 EP 780 DI 10.1029/97GL03636 PG 4 WC Geosciences, Multidisciplinary SC Geology GA ZD051 UT WOS:000072645900005 ER PT J AU Leonhardt, D Eddy, CR Shamamian, VA Fernsler, RF Butler, JE AF Leonhardt, D Eddy, CR Shamamian, VA Fernsler, RF Butler, JE TI Argon metastables in a high density processing plasma SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GLOW-DISCHARGES; POSITIVE-COLUMN; AR; ION; TEMPERATURES; SPECTROMETER; EXCITATION; ATOMS; CL2 AB Absolute densities of metastable argon atoms (Paschen 1 s(5), 1 s(3)) and the intermediate resonant state (1s(4)) were measured in a high density plasma etching environment. Excited species densities were measured ranging from 10(8) to 3x10(9) cm(-3), depending on the particular atomic state. A straightforward reaction rate formalism consisting of only two competing electron-atom collision rates accurately predicts such densities. Because of the low densities of these long-lived excited state species, all excited argon species need to be considered only as energy loss channels in modeling high density (10(11)-10(12) cm(-3)), low pressure (similar to 1 mTorr) plasma sources. Metastable production rates were also used to identify energy transfer mechanisms under etching conditions of Cl-2/Ar mixtures and substrate biasing in the reactor. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Leonhardt, D (reprint author), USN, Res Lab, Div Chem, Code 6174, Washington, DC 20375 USA. EM darrin@ccf.nrl.navy.mil RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 33 TC 31 Z9 31 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 15 PY 1998 VL 83 IS 6 BP 2971 EP 2979 DI 10.1063/1.367123 PG 9 WC Physics, Applied SC Physics GA ZC998 UT WOS:000072640700015 ER PT J AU Gillespie, DT AF Gillespie, DT TI Theory of electrical noise induced in a wire loop by the thermal motions of ions in solution SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Continuous Markov process theory is used to model the electrical noise induced in a passive wire loop by the thermal motions of ions in a nearby solution. The ions, being charged particles in Brownian motion, generate a fluctuating magnetic field, and that in turn induces a fluctuating electromotive force (emf) that augments the loop's Johnson emf. It is shown that the spectral density function of the equilibrium current in the wire loop is thereby increased, for moderate cycle frequencies nu, by approximately a factor (1 + alpha nu(2)), where alpha is determined by the geometry of the system, the resistance of the loop, and the charges, diffusion coefficients, and concentrations of the solution ions. It is also shown that the temporal trajectory of the loop current becomes "thickened," in a randomly fuzzy way, by an approximate factor of the form (1 + beta)(1/2), where beta depends not only on the aforementioned parameters that determine alpha, but also on the hydrated masses of the ions. These findings may be useful for estimating the intrinsic background noise in the detector coil of a medical magnetic resonance imaging machine, or any other sensitive electronic circuit that is required to operate in an immediate "salt water" environment. C1 USN, Air Warfare Ctr, Computat Sci Branch, China Lake, CA 93555 USA. RP USN, Air Warfare Ctr, Computat Sci Branch, Code 4B4000D, China Lake, CA 93555 USA. EM dtg@rattler.chinalake.navy.mil NR 15 TC 4 Z9 4 U1 1 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 MAR 15 PY 1998 VL 83 IS 6 BP 3118 EP 3128 DI 10.1063/1.367068 PG 11 WC Physics, Applied SC Physics GA ZC998 UT WOS:000072640700038 ER PT J AU Kang, JU Frankel, MY Esman, RD Thompson, DA Robinson, BJ AF Kang, JU Frankel, MY Esman, RD Thompson, DA Robinson, BJ TI Dependence of carrier lifetime and resistivity on annealing in InP grown by He-plasma-assisted molecular beam epitaxy SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GAAS AB We have experimentally investigated the carrier lifetime and resistivity versus anneal temperature in InP films grown by He-plasma-assisted molecular beam epitaxy. This material is shown to exhibit picosecond carrier lifetime with high resistivity even after anneal at temperatures up to 700 degrees C. (C) 1998 American Institute of Physics. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. McMaster Univ, Ctr Electrophoton Mat & Devices, Hamilton, ON L8S 4L7, Canada. RP Kang, JU (reprint author), USN, Res Lab, Div Opt Sci, Code 5672, Washington, DC 20375 USA. RI Kang, Jin/A-3228-2010 NR 7 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 15 PY 1998 VL 83 IS 6 BP 3423 EP 3425 DI 10.1063/1.367110 PG 3 WC Physics, Applied SC Physics GA ZC998 UT WOS:000072640700084 ER PT J AU Jiang, L Garwood, RW AF Jiang, L Garwood, RW TI Effects of topographic steering and ambient stratification on overflows on continental slopes: A model study SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID DENMARK STRAIT OVERFLOW; TALL ISOLATED SEAMOUNT; SLOPING BOTTOM; DEEP-WATER; BAROCLINIC INSTABILITY; UPWELLING CIRCULATION; NUMERICAL-SIMULATION; SUBMARINE-CANYON; NORTH-ATLANTIC; ARCTIC-OCEAN AB The three-dimensional flow structures of cold dense overflow water on continental slopes with and without along-slope topographic variations and ambient slope water stratification are investigated, using a three-dimensional numerical ocean model. We discuss the effects of topographic steering and ambient stratification on the downslope transport of dense overflow on continental slopes. A constant upstream inflow of dense water is specified at the upper edge of the slope that represents an overflow from a marginal sea. We present the numerical simulations for overflow plumes in the presence of three topographic features: a cross-slope canyon that leads from the coast to the deep ocean, a cross-slope ridge, and a seamount. We compared the numerical results with the previously published results of overflow plumes on a uniform slope without ambient water stratification. In the presence of a canyon, a portion of the dense water descends into the canyon, forming a bottom-trapped plume that flows offshore along the right side (facing the ocean) of the canyon. The numerical result indicates that intensive mixing and entrainment occur in the canyon plume. The remainder of the overflow flows across the canyon and keeps descending on the slope while being deflected to the right-hand side of the inflow. In the presence of a cross-slope ridge, part of the water is blocked by the ridge and the flow is confined along the left side of the ridge. The remaining portion of the plume water flows over the ridge toward the right-hand side of the inflow. The presence of a canyon or a ridge significantly enhances the downslope transport of dense water compared with the uniformly sloping bottom case. A seamount does not affect the cross-isobath transport of dense water as much as does a canyon or a ridge. A seamount does influence the mixing, entrainment, and the plume trajectories. Ambient slope water stratification has significant influence on the mixing and cross-slope penetration of the overflow plumes. It has hindered the downslope penetration of the plumes as a result of enhanced mixing and entrainment when the plumes encounter deep denser water. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Jiang, L (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 50 TC 30 Z9 30 U1 1 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 MAR 15 PY 1998 VL 103 IS C3 BP 5459 EP 5476 DI 10.1029/97JC03201 PG 18 WC Oceanography SC Oceanography GA ZB957 UT WOS:000072525300009 ER PT J AU Gelaro, R Buizza, R Palmer, TN Klinker, E AF Gelaro, R Buizza, R Palmer, TN Klinker, E TI Sensitivity analysis of forecast errors and the construction of optimal perturbations using singular vectors SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID ENSEMBLE PREDICTION; OPTIMAL EXCITATION; PREDICTABILITY; INSTABILITY; CIRCULATION; ADJOINT; GROWTH; SYSTEM; WAVES AB The sensitivity of forecast errors to initial conditions is used to examine the optimality of perturbations constructed from the singular vectors of the tan ent propagator of the European Centre for Medium-Range Weather Forecasts model. Sensitivity and pseudo-inverse perturbations based on the 48-h forecast error are computed as explicit linear combinations of singular vectors optimizing total energy over the Northern Hemisphere. It is assumed that these perturbations are close to the optimal perturbation that can be constructed from a linear combination of these singular vectors. Optimality is measured primarily in terms of the medium range forecast improvement obtained by adding the perturbations a posteriori to the initial conditions. Several issues are addressed in the context of these experiments, including the ability of singular vectors to describe forecast error growth beyond the optimization interval, the number of singular vectors required, and the implications of nonmodal error growth. Supporting evidence for the use of singular vectors based on a total energy metric for studying atmospheric predictability is also presented. In general, less than 30 singular vectors capture a large fraction of the variance of the Northern Hemisphere sensitivity pattern obtained from a T63 adjoint model integration, especially in cases of low forecast skill. The sensitivity patterns for these eases tend to he highly localized with structures determined by the dominant singular vectors. Forecast experiments with these perturbations show significant improvements in skill in the medium range, indicating that singular vectors optimized for a short-range forecast continue to provide a useful description of error growth sell beyond this time. The results suggest that ensemble perturbations based on 10-30 singular vectors should provide a reasonable description of the medium-range forecast uncertainty, although the inclusion of additional singular vectors is likely to be beneficial. Nonmodality is a keg consideration in the construction of optimal perturbations. There is virtually no projection between the contemporaneous unstable subspaces at the end or one forecast trajectory portion and the beginning of a second, consecutive portion. Sensitivity and ensemble perturbations constructed using the evolved singular vectors from a previous (day-2) forecast are suboptimal for the current (day+0) forecast initial conditions. It is argued that these results have implications for a range of issues in atmospheric predictability including ensemble weather prediction, data assimilation, and the development of adaptive observing techniques. C1 European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England. RP Gelaro, R (reprint author), USN, Res Lab, 7 Grace Hopper Ave, Monterey, CA 93943 USA. EM gelaro@nrlmry.navy.mil OI Palmer, Tim/0000-0002-7121-2196 NR 35 TC 93 Z9 100 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 MAR 15 PY 1998 VL 55 IS 6 BP 1012 EP 1037 DI 10.1175/1520-0469(1998)055<1012:SAOFEA>2.0.CO;2 PG 26 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZB373 UT WOS:000072465500007 ER PT J AU Kim, SG Mazin, II Singh, DJ AF Kim, SG Mazin, II Singh, DJ TI First-principles study of Zn-Sb thermoelectrics SO PHYSICAL REVIEW B LA English DT Article ID SKUTTERUDITE ANTIMONIDES AB We report local-density-approximation calculations of the electronic structure and thermoelectric properties of beta-Zn4Sb3. The material is a low carrier density metal with a complex Fermi-surface topology and a nontrivial dependence of the Hall concentration on the band filling. The band structure is rather covalent, consistent with experimental observations of good carrier mobility. At a band filling corresponding to the experimental Hall number, the calculated thermopower and temperature dependence are in good agreement with experiment. The high Seebeck coefficient in a metallic material is remarkable, and arises in part from the strong energy dependence of the Fermi surface topology near the experimental band filling. An improved thermoelectric performance is predicted for lower doping levels, i.e., higher Zn concentrations. C1 UES Inc, Washington, DC 20375 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. George Mason Univ, Computat Sci Inst, Fairfax, VA 22030 USA. RP Kim, SG (reprint author), UES Inc, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008; Singh, David/I-2416-2012 NR 18 TC 61 Z9 63 U1 0 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 MAR 15 PY 1998 VL 57 IS 11 BP 6199 EP 6203 DI 10.1103/PhysRevB.57.6199 PG 5 WC Physics, Condensed Matter SC Physics GA ZD807 UT WOS:000072726400001 ER PT J AU Bayer, M Walck, SN Reinecke, TL Forchel, A AF Bayer, M Walck, SN Reinecke, TL Forchel, A TI Exciton binding energies and diamagnetic shifts in semiconductor quantum wires and quantum dots SO PHYSICAL REVIEW B LA English DT Article ID STATES; QUANTIZATION; WELLS; CONFINEMENT; BOXES AB Systematic studies of the effects of confinement and reduced dimensionality on excitons in quantum wires and quantum dots have been made on systems with widely varying sizes. Diamagnetic shifts are obtained from low-intensity magnetophotoluminescence spectroscopy, and exciton energies are estimated using an anisotropic bulk exciton model. Modulated barrier and deep-etched In0.10Ga0.90As/GaAs structures are used in order to study the dependence on the lateral potential offset. Calculations of the diamagnetic shifts and the binding energies are made using variational techniques, and are found to be in good agreement with experiment. For the size studied experimentally, the binding energies are found to be enhanced by up to four times the bulk value for wires, and by five times for dots. Further, confinement is found to have significant effects on the excitonic properties for structure sizes up to ten times the Bohr radius. C1 Univ Wurzburg, D-97074 Wurzburg, Germany. USN, Res Lab, Washington, DC 20375 USA. RP Bayer, M (reprint author), Univ Wurzburg, D-97074 Wurzburg, Germany. OI Forchel, Alfred/0000-0002-9377-9935 NR 27 TC 88 Z9 89 U1 3 U2 19 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 MAR 15 PY 1998 VL 57 IS 11 BP 6584 EP 6591 DI 10.1103/PhysRevB.57.6584 PG 8 WC Physics, Condensed Matter SC Physics GA ZD807 UT WOS:000072726400063 ER PT J AU Mazin, II Singh, DJ AF Mazin, II Singh, DJ TI Nonlocal density functionals and the linear response of the homogeneous electron gas SO PHYSICAL REVIEW B LA English DT Article ID EXCHANGE; APPROXIMATION; MOLECULES; SYSTEMS; SOLIDS; ENERGY; ATOMS AB The known and usable truly nonlocal functionals for exchange-correlation energy of the inhomogeneous electron gas are the ADA (average density approximation) and the WDA (weighted density approximation). ADA, by design, yields the correct linear response function of the uniform electron gas. The WDA is constructed so that it is exact in the opposite limit of one-electron systems, and it was conjectured that the WDA is also accurate in the uniform gas limit. To test this conjecture, we derive an expression for the linear response of the uniform gas in the WDA, and calculate it for several flavors of the WDA. We then compare the results with the Monte Carlo data on the exchange-correlation local-held correction, and identify the weak points of conventional WDA in the homogeneous limit. We suggest how the WDA can be modified to improve the response function. The resulting approximation is a good one in both opposite limits. Future testing should show whether it will also be better than conventional WDA and ADA for practical nonlocal density-functional calculations. C1 USN, Res Lab, Washington, DC 20375 USA. George Mason Univ, CSI, Fairfax, VA 22030 USA. RP Mazin, II (reprint author), USN, Res Lab, Code 6691, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008; Singh, David/I-2416-2012 NR 17 TC 16 Z9 16 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 MAR 15 PY 1998 VL 57 IS 12 BP 6879 EP 6883 DI 10.1103/PhysRevB.57.6879 PG 5 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300028 ER PT J AU Steinert, SA Streib-Montee, R Leather, JM Chadwick, DB AF Steinert, SA Streib-Montee, R Leather, JM Chadwick, DB TI DNA damage in mussels at sites in San Diego Bay SO MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS LA English DT Article DE DNA damage; comet assay; environmental contaminant; mussel ID POLYCYCLIC AROMATIC-HYDROCARBONS; GEL-ELECTROPHORESIS ASSAY; COMET ASSAY; TOXICITY; CELLS; SEDIMENTS; ANTHRACENE; APOPTOSIS; RADIATION; REPAIR AB Identification and assessment of introduced and other toxicants is crucial to any comprehensive study of contaminants within the marine environment. The relationship between DNA single-strand breaks and the exposure of marine organisms to environmental contaminants was examined at sites in San Diego Bay, CA. A comprehensive assessment of the extent and consequences of marine environmental contamination in the area of Naval Station San Diego was conducted in the summer of 1995. The study addressed contamination sources, distributions, concentrations,transport, sediment-water exchange, biological effects, and degradation. The biological effects portion of the study (this paper) included contaminant bioaccumulation, organismal growth, and the determination of DNA single-strand breaks using the Comet assay. DNA damage was determined in hemocytes collected from deployed and resident mussels, Mytilus edulis, at six stations in and around the Naval Station San Diego. Deployed mussels were exposed on station for similar to 30 days in plastic mesh bags, placed 1 m above the bottom. Hemocyte samples were collected on days 0, 12, and 32. It was found that stations exhibiting the extremes of contaminant exposure, both highest and lowest concentrations, were easily identified using growth and DNA damage measurements. Sediment chemistry and bioaccumulation data indicated, Hg, Cu, and Zn, to be the most notable contaminants. The Comet assay, and in particular germ cell DNA damage determinations, were found to respond rapidly to station contaminants. Results from this study and an earlier 1993 study suggest that the non-sediment associated effects observed at one station may have been the result of the photoactivation of accumulated PAHs. (C) 1998 Elsevier Science B.V. C1 Dept Marine Sci, San Diego, CA 92110 USA. USN, Command Control & Ocean Surveillance Ctr, San Diego, CA 92152 USA. RP Dept Marine Sci, 4045 Hancock St, San Diego, CA 92110 USA. EM steinert@cod.nosc.mil NR 39 TC 118 Z9 125 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0027-5107 EI 1873-135X J9 MUTAT RES-FUND MOL M JI Mutat. Res.-Fundam. Mol. Mech. Mutagen. PD MAR 13 PY 1998 VL 399 IS 1 BP 65 EP 85 DI 10.1016/S0027-5107(97)00267-4 PG 21 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA ZP188 UT WOS:000073726300007 PM 9635490 ER PT J AU Ma, W Pancrazio, JJ Coulombe, M Dumm, J Sathanoori, RS Barker, JL Kowtha, VC Stenger, DA Hickman, JJ AF Ma, W Pancrazio, JJ Coulombe, M Dumm, J Sathanoori, RS Barker, JL Kowtha, VC Stenger, DA Hickman, JJ TI Neuronal and glial epitopes and transmitter-synthesizing enzymes appear in parallel with membrane excitability during neuroblastoma x glioma hybrid differentiation SO DEVELOPMENTAL BRAIN RESEARCH LA English DT Article DE NG108-15 cell line; serum-free medium; excitability; patch-clamp; neural protein; neurotransmitter enzyme; bromodeoxyuridine; proliferation; differentiation ID NG108-15 CELLS; SYNAPSE FORMATION; DEFINED MEDIUM; NEURAL TUMOR; PROLIFERATION; MODULATION; INVIVO; CYCLE; LINE AB The membrane excitability and the presence of neural proteins, including neuronal and glial markers and neurotransmitter-synthesizing enzymes, were examined in parallel while the NG108-15 cell line was maintained in a serum-free medium. Whole-cell recordings in voltage-clamp or current-clamp configurations were used to evaluate the membrane excitability, and immunostaining was done with a panel of well-characterized antibodies against NSE, NF150, S-100 beta, GFAP, ChAT and TH. Culture for 4 to 10 days led to a striking rise in neurite outgrowth, electrical excitability and expression of neural proteins in type I neuron-like cells, which were of both neuronal and glial character, and expressed both cholinergic and adrenergic traits. After about 2 weeks, type II cells which lack neurite processes began to emerge. The type II cells proliferated, as revealed by BrdU uptake, and gradually overgrew differentiated cell types. They exhibited little or no membrane excitability and absence of immunoreactivity for the neuronal and glial specific proteins tested. These measurements indicate that the presence of these neural proteins at crucial stages of membrane excitability development is an important characteristic of NG108-15 cell differentiation, providing insights into the neural development and the reversible nature of neoplasia in the nervous system. (C) 1998 Elsevier Science B.V. C1 Sci Applicat Int Corp, Biotechnol Res & Applicat Div, Rockville, MD 20850 USA. NINDS, Neurophysiol Lab, NIH, Bethesda, MD 20892 USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Ma, W (reprint author), Sci Applicat Int Corp, Biotechnol Res & Applicat Div, 6 Taft Court,Suite 300, Rockville, MD 20850 USA. RI Pancrazio, Joseph/M-3206-2015 OI Pancrazio, Joseph/0000-0001-8276-3690 NR 27 TC 23 Z9 24 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-3806 J9 DEV BRAIN RES JI Dev. Brain Res. PD MAR 12 PY 1998 VL 106 IS 1-2 BP 155 EP 163 DI 10.1016/S0165-3806(97)00208-3 PG 9 WC Developmental Biology; Neurosciences SC Developmental Biology; Neurosciences & Neurology GA ZH101 UT WOS:000073072200016 ER PT J AU Honeycutt, RK Robertson, JW Turner, GW Henden, AA AF Honeycutt, RK Robertson, JW Turner, GW Henden, AA TI V446 Herculis (nova her 1960) is an optical triple: Implications for the resumption of dwarf nova outbursts following the nova SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries, close; novae, cataclysmic variables; stars, individual (V446 Herculis) ID LIMIT-CYCLE MECHANISM; X-RAY BINARIES; GK-PERSEI; OLD-NOVA; CATACLYSMIC BINARIES; CLASSICAL NOVAE; HIBERNATION; EVOLUTION; ERUPTIONS; CATALOG AB V446 Her has been reported to have outbursts or flares at a mean interval of similar to 23 days with an amplitude of similar to 1.5 mag. This amplitude is quite low for dwarf nova outbursts, which suggests that these events may be due to mass transfer modulations. However, earlier reported photometry included an unrecognized contribution from two additional stars similar to 3 " away. When corrected for this effect, the amplitude of the outbursts is increased to similar to 2.5 mag, consistent with the amplitudes of known dwarf novae. Furthermore, it is found that other parameters of the outbursts are consistent with the expected characteristics of dwarf nova events. These parameters include the outburst spacing, the rise and fall times of the outbursts, and variations in outburst amplitude and width. V446 Her is therefore firmly established as a cataclysmic variable that has dwarf nova eruptions in the immediate postnova stage, and is the most unambiguous example of such behavior among the recorded novae. C1 Indiana Univ, Dept Astron, Bloomington, IN 47405 USA. USN Observ, USRA, Flagstaff Stn, Flagstaff, AZ 86002 USA. RP Honeycutt, RK (reprint author), Indiana Univ, Dept Astron, Swain Hall W, Bloomington, IN 47405 USA. EM honey@astro.indiana.edu; bigjay@astro.indiana.edu; turner@astro.indiana.edu; aah@nofs.navy.mil NR 36 TC 16 Z9 16 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 1998 VL 495 IS 2 BP 933 EP 940 DI 10.1086/305299 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZD699 UT WOS:000072714200037 ER PT J AU Russell, JN Leming, A Morris, RE AF Russell, JN Leming, A Morris, RE TI Phenol decomposition on Al(111) SO SURFACE SCIENCE LA English DT Article DE alcohols; aluminum; aromatics; low index single crystal surfaces; surface chemical reaction; thermal desorption; thermal desorption spectroscopy ID OXYGEN-PRECOVERED MO(110); SURFACE PHENOXIDE; ALUMINUM SURFACES; DESORPTION; ELECTRON; ADSORPTION; METHANOL; NI(110); SPECTROSCOPY; ADSORBATES AB The reaction of phenol on Al(111) was investigated between 100 and 800 K with temperature programmed desorption and Auger electron spectroscopy. Molecular phenol desorbed at 200 K from the multilayer. The first monolayer of phenol decomposed into hydrogen, benzene, and adsorbed oxygen and carbon as the surface was heated. The sequence of bond scission was determined using deuterium labeling. Three H-2 desorption peaks were observed. The first Hz desorption peak was from the dissociation of the hydroxyl group and was observed around 380 K. The second H-2 desorption peak, which started around 450 K and reached a maximum at 510 K, resulted from the scission of the C-H bonds in the 2 or 6 positions on the ring. The third H-2 desorption peak was observed at 680 K and was from scission of the C-H bonds on the remaining hydrocarbon fragments on the surface. Benzene desorption occurred between 450 and 700 K with maxima at 490 and 630 K resulting from hydrogen addition to the phenyl group from OH and CxHy moieties, respectively. H/D exchange with the hydrogen on the phenyl ring also was observed. However, there was no evidence for hydrogenation (saturation) of any of the double bonds of the ring. After heating to 800 K, some O and C remained on the surface. (C) 1998 Elsevier Science B.V. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Russell, JN (reprint author), USN, Res Lab, Div Chem, Washington, DC 20375 USA. EM john.n.russell@nrl.navy.mil RI Russell, John/A-3621-2009 NR 34 TC 15 Z9 15 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAR 10 PY 1998 VL 399 IS 2-3 BP 239 EP 247 DI 10.1016/S0039-6028(97)00823-6 PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA ZG549 UT WOS:000073014800013 ER PT J AU Bennett, BR Yang, MJ Shanabrook, BV Boos, JB Park, D AF Bennett, BR Yang, MJ Shanabrook, BV Boos, JB Park, D TI Modulation doping of InAs/AlSb quantum wells using remote InAs donor layers SO APPLIED PHYSICS LETTERS LA English DT Article ID FIELD-EFFECT TRANSISTORS; INTERFACE; BARRIERS AB Sheet carrier concentrations in quantum wells of InAs clad by AlSb were enhanced by modulation doping with very thin (9-12 Angstrom) remote InAs(Si) donor layers. The growth temperature of the donor layers was a key parameter, with relatively low temperatures required to minimize Si segregation into the AlSb. Sheet carrier concentrations as high as 3.2X10(12)/cm(2) and 5.6X10(12)/cm(2) were achieved by single-and double-sided modulation doping, respectively. High electron mobility transistors fabricated using the modulation doped structure exhibited a unity current gain cut-off frequency of 60 GHz for a 0.5 mu m gate length at a source-drain voltage of 0.5 V. [S0003-6951(98)01010-9]. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RP Bennett, BR (reprint author), USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 18 TC 27 Z9 27 U1 2 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 MAR 9 PY 1998 VL 72 IS 10 BP 1193 EP 1195 DI 10.1063/1.121010 PG 3 WC Physics, Applied SC Physics GA ZA514 UT WOS:000072370900022 ER PT J AU Smathers, JB Kneedler, E Bennett, BR Jonker, BT AF Smathers, JB Kneedler, E Bennett, BR Jonker, BT TI Nanometer scale surface clustering on ZnSe epilayers SO APPLIED PHYSICS LETTERS LA English DT Article ID GROWTH; INTERFACES; MICROSCOPY; EPITAXY; GAAS AB We have used atomic force microscopy to investigate the surface morphology of ZnSe films grown on GaAs(001) by molecular beam epitaxy. We report the observation of nanometer scale surface clusters 400-1200 Angstrom in diameter and 60-200 Angstrom in height. The clusters form ex situ as the result of the initial exposure of the ZnSe to atmosphere, and undergo Ostwald ripening at room temperature. Our observations, combined with the relevant literature, suggest that the cluster composition is SeO2. We propose that the oxidation of the ZnSe epilayers produces a thin layer of SeO2 which migrates to form surface clusters on a stable, zinc-related oxide surface. These findings should facilitate greater control of surface morphologies during ZnSe based device fabrication processes. [S0003-6951(98)02610-2]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Smathers, JB (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 21 TC 42 Z9 44 U1 1 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 MAR 9 PY 1998 VL 72 IS 10 BP 1238 EP 1240 DI 10.1063/1.121025 PG 3 WC Physics, Applied SC Physics GA ZA514 UT WOS:000072370900037 ER PT J AU Pecora, LM Carroll, TL AF Pecora, LM Carroll, TL TI Master stability functions for synchronized coupled systems SO PHYSICAL REVIEW LETTERS LA English DT Article ID OSCILLATOR-SYSTEMS; CHAOTIC OSCILLATORS; RIDDLED BASINS; BIFURCATIONS; ORBITS AB We show that many coupled oscillator array configurations considered in the literature can be put into a simple form so that determining the stability of the synchronous state can be done by a master stability function, which can be tailored to one's choice of stability requirement. This solves, once and for all, the problem of synchronous stability for any linear coupling of that oscillator. C1 USN, Res Lab, Washington, DC 20375 USA. RP Pecora, LM (reprint author), USN, Res Lab, Code 6343, Washington, DC 20375 USA. OI Carroll, Thomas/0000-0002-2371-2049 NR 22 TC 1249 Z9 1301 U1 9 U2 71 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 MAR 9 PY 1998 VL 80 IS 10 BP 2109 EP 2112 DI 10.1103/PhysRevLett.80.2109 PG 4 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400021 ER PT J AU Kuno, M Nirmal, M Bawendi, G Efros, A Rosen, M AF Kuno, M Nirmal, M Bawendi, G Efros, A Rosen, M TI Magnetic circular dichroism study of CdSe quantum dots SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SEMICONDUCTOR MICROCRYSTALLITES; EXCHANGE INTERACTION; CONFINEMENT; NANOCRYSTALS; ELECTRON; EXCITON; DARK AB We study the magnetic circular dichroism (MCD) of exciton states near the band edge of CdSe nanocrystallites (quantum dots). The experiment probes the difference between left and right circularly polarized transitions in the presence of an external magnetic field. Analysis of the MCD signal determines the sign and magnitude of the: exciton g-factor which is shown to be highly sensitive to the energy band parameters used in the effective mass approximation, The observation of theoretically predicted changes in The sign of the exciton g-factor between the first two transitions is in agreement with recent theory describing the presence of fine structure underlying the optical transitions of CdSe nanocrystallites. (C) 1998 American Institute of Physics. [S0021-9606(98)02010-8]. C1 MIT, Cambridge, MA 02139 USA. USN, Res Lab, Nanostruct Opt Struct, Washington, DC 20375 USA. RP Kuno, M (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Kuno, Masaru/K-2673-2012 NR 18 TC 49 Z9 49 U1 0 U2 18 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 MAR 8 PY 1998 VL 108 IS 10 BP 4242 EP 4247 DI 10.1063/1.475823 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZA530 UT WOS:000072373500046 ER PT J AU Huang, NE Shen, Z Long, SR Wu, MLC Shih, HH Zheng, QN Yen, NC Tung, CC Liu, HH AF Huang, NE Shen, Z Long, SR Wu, MLC Shih, HH Zheng, QN Yen, NC Tung, CC Liu, HH TI The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time series analysis SO PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article DE non-stationary time series; nonlinear differential equations; frequency-time spectrum; Hilbert spectral analysis; intrinsic time scale; empirical mode decomposition ID FREQUENCY SIGNAL ANALYSIS; WIGNER DISTRIBUTION; EL-NINO; WAVES; GEOSAT; TOOL; MOTION; OCEAN; FLOW AB A new method for analysing nonlinear and non-stationary data has been developed. The key part of the method is the 'empirical mode decomposition' method with which any complicated data set can be decomposed into a finite and often small number of 'intrinsic mode functions' that admit well-behaved Hilbert transforms. This decomposition method is adaptive, and, therefore, highly efficient. Since the decomposition is based on the local characteristic time scale of the data, it is applicable to nonlinear and non-stationary processes. With the Hilbert transform, the 'instrinic mode functions' yield instantaneous frequencies as functions of time that give sharp identifications of imbedded structures. The final presentation of the results is an energy-frequency-time distribution, designated as the Hilbert spectrum. In this method, the main conceptual innovations are the introduction of 'intrinsic mode functions' based on local properties of the signal, which makes the instantaneous frequency meaningful; and the introduction of the instantaneous frequencies for complicated data sets, which eliminate the need for spurious harmonics to represent nonlinear and non-stationary signals. Examples from the numerical results of the classical nonlinear equation systems and data representing natural phenomena are given to demonstrate the power of this new method. Classical nonlinear system data are especially interesting, for they serve to illustrate the roles played by the nonlinear and non-stationary effects in the energy-frequency-time distribution. C1 NASA, Lab Hydrospher Proc, Oceans & Ice Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Earth & Planetary Sci, Baltimore, MD 21218 USA. NASA, Lab Hydrospher Proc, Observ Sci Branch, Wallops Flight Facil, Wallops Island, VA 23337 USA. NASA, Atmospheres Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Ocean Serv, NOAA, Silver Spring, MD 20910 USA. Univ Delaware, Coll Marine Studies, Newark, DE 19716 USA. USN, Res Lab, Washington, DC 20375 USA. N Carolina State Univ, Dept Civil Engn, Raleigh, NC 27695 USA. USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20084 USA. RP Huang, NE (reprint author), NASA, Lab Hydrospher Proc, Oceans & Ice Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Zheng, Quanan/F-9025-2010; Long, Steven/D-7248-2012 NR 64 TC 6236 Z9 8050 U1 74 U2 546 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-5021 EI 1471-2946 J9 P ROY SOC A-MATH PHY JI Proc. R. Soc. A-Math. Phys. Eng. Sci. PD MAR 8 PY 1998 VL 454 IS 1971 BP 903 EP 995 PG 93 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZD271 UT WOS:000072668500010 ER EF