FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Eberhard, WG Garcia-C, JM Lobo, J AF Eberhard, WG Garcia-C, JM Lobo, J TI Size-specific defensive structures in a horned weevil confirm a classic battle plan: avoid fights with larger opponents SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE allometry; weapons; beetle horns; weevils ID SCARABAEIDAE; DIMORPHISM; COLEOPTERA AB A rigid sheath that extends deep into the prothorax of male Parisoschoenus expositus serves to receive the horns of opponents in battles over females. The male cannot use his own horn unless he receives his opponent's horn in his sheath. The length of a male's sheath is always approximately equal to the length of his own horns, so his body design is appropriate only for horn-locking battles with males whose horns are equal to or shorter than his own. Horn length and sheath length are dimorphic with respect to each other and to an indicator of body size. The switch points between morphs are very nearly the same for several relationships, so the different aspects of fighting morphology are tightly coordinated. C1 Univ Costa Rica, Escuela Biol, San Jose, Costa Rica. Smithsonian Trop Res Inst, Balboa, Panama. RP Eberhard, WG (reprint author), Univ Costa Rica, Escuela Biol, Ciudad Univ, San Jose, Costa Rica. EM iriartea@sol.racsa.co.cr NR 8 TC 32 Z9 32 U1 0 U2 6 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD JUN 7 PY 2000 VL 267 IS 1448 BP 1129 EP 1134 DI 10.1098/rspb.2000.1118 PG 6 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 324JA UT WOS:000087617500009 PM 10885518 ER PT J AU Martin, AP Bermingham, E AF Martin, AP Bermingham, E TI Regional endemism and cryptic species revealed by molecular and morphological analysis of a widespread species of Neotropical catfish SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE Neotropical; catfish; phylogenetics; biodiversity ID SOUTH-AMERICA; RAIN-FOREST; PHYLOGEOGRAPHY; DNA AB The lower Central American landscape was fully emergent approximately three million years ago, an event which marked the beginning of the Great American biotic interchange. Freshwater fishes participated in the biotic interchange. Because primary freshwater fishes are restricted to freshwater, they provide an excellent system for investigating the interplay of historical and recent processes on the assembly, structure and diversity of the regions' aquatic ecosystems. We focused on examining the history of diversification for a species of catfish (Pimelodella chagresi) whose distribution spans multiple, isolated drainage basins across the Isthmian landscape and into north-western South America. Analysis of mitochondrial DNA haplotypes and morphological traits indicated that P. chagresi, as currently recognized, comprises a species complex. In addition, along the Pacific slope of Panama, repeated dispersion. diversification, extinction and possibly hybridization are thought to underlie a complex distribution of haplotypes. Overall, the results underscore the tremendous importance of historical processes on regional biodiversity. C1 Univ Colorado, Dept Environm Populat & Organism Biol, Boulder, CO 80309 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Martin, AP (reprint author), Univ Colorado, Dept Environm Populat & Organism Biol, Boulder, CO 80309 USA. EM am@stripe.colorado.edu NR 21 TC 39 Z9 39 U1 1 U2 6 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD JUN 7 PY 2000 VL 267 IS 1448 BP 1135 EP 1141 DI 10.1098/rspb.2000.1119 PG 7 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 324JA UT WOS:000087617500010 PM 10885519 ER PT J AU Sharrer, GT AF Sharrer, GT TI Rooted in America: Foodlore of popular fruits and vegetables. SO AGRICULTURAL HISTORY LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Sharrer, GT (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA C/O JOURNALS DIVISION, 2000 CENTER ST, STE 303, BERKELEY, CA 94704-1223 USA SN 0002-1482 J9 AGR HIST JI Agric. Hist. PD SUM PY 2000 VL 74 IS 3 BP 714 EP 715 PG 2 WC Agriculture, Multidisciplinary; History; History & Philosophy Of Science SC Agriculture; History; History & Philosophy of Science GA 376GY UT WOS:000165450900015 ER PT J AU McMullen, A AF McMullen, A TI Playing Indian. SO AMERICAN ANTHROPOLOGIST LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Indian, Washington, DC 20560 USA. RP McMullen, A (reprint author), Smithsonian Inst, Natl Museum Amer Indian, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER ANTHROPOLOGICAL ASSOC PI ARLINGTON PA 4350 NORTH FAIRFAX DRIVE SUITE 640, ARLINGTON, VA 22203 USA SN 0002-7294 J9 AM ANTHROPOL JI Am. Anthropol. PD JUN PY 2000 VL 102 IS 2 BP 416 EP 417 DI 10.1525/aa.2000.102.2.416 PG 2 WC Anthropology SC Anthropology GA 483LD UT WOS:000171636100070 ER PT J AU Hunter, TR Churchwell, E Watson, C Cox, P Benford, DJ Roelfsema, PR AF Hunter, TR Churchwell, E Watson, C Cox, P Benford, DJ Roelfsema, PR TI 350 micron images of massive star formation regions SO ASTRONOMICAL JOURNAL LA English DT Article DE H Pi regions; infrared radiation; stars : formation ID H-II REGIONS; DUST TEMPERATURE DISTRIBUTIONS; ANGULAR-RESOLUTION CAMERA; ULTRACOMPACT HII-REGIONS; H2O MASER SOURCES; METHANOL MASERS; GALACTIC-CENTER; CONTINUUM OBSERVATIONS; VLA OBSERVATIONS; RADIO-SOURCES AB We present 350 mu m continuum images of 24 massive star formation regions obtained with the Caltech Submillimeter Observatory equipped with the SHARC focal-plane array. At this wavelength the spatial resolution is 11 ". The 350 mu m emission is compared with thermal radio continuum emission and OH, H2O, and CH3OH masers. Emission at 350 mu m is believed to be thermal emission from dust heated by embedded or nearby stars. Compact radio continuum sources are usually present in the mapped 350 mu m fields, and more than 60% of the 350 mu m peaks coincide with radio continuum peaks. This association lends strong support to the notion that the dust is heated primarily by hot stars. Masers are also a common property of massive star formation regions. Usually OH, H2O, and/or CH3OH masers are found near, but generally not coincident with, the 350 mu m peaks. Less than 25% of the 350 Irm peaks have no reported masers located close by. In most of the observed regions, the 350 mu m dust maps show one or more components surrounded by fainter extended emission. In total, we identify 28 separate 350 mu m components. Ten of the 28 components do not have radio continuum counterparts. These are luminous sources and should produce detectable H II regions. It is postulated that these sources may be undergoing such rapid accretion that the infalling matter quenches the H II region very close to the protostar, thereby making the H II region undetectable in free-free emission. Objects in this evolutionary state may well represent the long-sought precursors to ultracompact H II regions and should have the properties of accreting massive protostars (e.g., accretion disks, bipolar molecular outflows, hot shocked gas, infall with spin-up toward the protostar). We suggest that the 10 sources in this category in our sample merit further observational study for these properties. Two-temperature graybody models constrained by the observed infrared spectral energy distributions were calculated to estimate the total mass, luminosity, average dust temperature, and hydrogen column and number densities for each source. The graybody models do not account for possible low-level emission from the coolest dust (<25 K) and therefore may underestimate the total mass. There is, however, no evidence for emission in excess of the models at 1.3 mm, and we conclude that the mass contribution of dust colder than similar to 25 K cannot be large. Thus, the graybody models shown provide useful average global properties required to understand massive star formation environments. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Wisconsin, Dept Astron, Washburn Observ, Madison, WI 53706 USA. Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Space Res Org Netherlands, NL-9700 AV Groningen, Netherlands. RP Hunter, TR (reprint author), Harvard Smithsonian Ctr Astrophys, MS-78,60 Garden St, Cambridge, MA 02138 USA. RI Benford, Dominic/D-4760-2012 OI Benford, Dominic/0000-0002-9884-4206 NR 48 TC 60 Z9 60 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD JUN PY 2000 VL 119 IS 6 BP 2711 EP 2727 DI 10.1086/301391 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 335ET UT WOS:000088231100015 ER PT J AU Rebull, LM Hillenbrand, LA Strom, SE Duncan, DK Patten, BM Pavlovsky, CM Makidon, R Adams, MT AF Rebull, LM Hillenbrand, LA Strom, SE Duncan, DK Patten, BM Pavlovsky, CM Makidon, R Adams, MT TI Circumstellar disk candidates identified from ultraviolet excesses in the Orion Nebula Cluster flanking fields SO ASTRONOMICAL JOURNAL LA English DT Article DE stars : pre-main-sequence ID T-TAURI STARS; ACCRETION DISKS; PROPER MOTIONS; MASS STARS; M-DWARFS; EMISSION; SEQUENCE AB We present an optical study of four 45' x 45' fields centered similar to 0.degrees 5 east, west, north, and south of the Orion Nebula Cluster center. We have measured V and I-C photometry for similar to 5000 stars, and U photometry for similar to 1600 of these. We have obtained spectral classifications for similar to 300 of the stars with UVIC photometry plus an additional similar to 200 stars located outside the area of our photometric survey. Dereddened photometry allows us to investigate the evidence for circumstellar accretion disks from excess emission at ultraviolet wavelengths, as well as the mass and age distributions of our sample. We find similar to 230 active accretion disk candidates and estimate the accretion disk fraction at greater than or equal to 40%. We use the magnitude of the ultraviolet excess to infer disk accretion rates. The mass accretion rate ((M) over bar) decreases slowly with age over the limited age range spanned by our data, 1-3 Myr, and increases slowly with mass over the limited mass range 0.2-1.2 M.. Although complicated selection effects are likely to affect the overall trends with mass and age, we are sensitive to, but do not see, high hi-values associated with the older ages and lower masses in our sample. The mean value of (M) over bar is similar to 10(-8) M. yr(-1), with a range of more than I order of magnitude at all ages and masses. We find an age and age spread for our sample of 10(6.0+/-0.4) y, with no variation within or between our fields. Meaningful constraint of the mass distribution is precluded because of the completeness limits of our survey. C1 Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Natl Opt Astron Observ, Tucson, AZ USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Texas, McDonald Observ, Ft Davis, TX 79734 USA. RP Rebull, LM (reprint author), Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. OI Rebull, Luisa/0000-0001-6381-515X NR 41 TC 52 Z9 52 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD JUN PY 2000 VL 119 IS 6 BP 3026 EP 3043 DI 10.1086/301393 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 335ET UT WOS:000088231100037 ER PT J AU Evans, NR AF Evans, NR TI V1334 Cygni: A triple system containing a classical Cepheid SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : spectroscopic; Cepheids; stars : evolution; stars : fundamental parameters ID U-AQUILAE; MASS; OVERTONE; MODELS; RATIOS; ORBIT AB We have observed the small-amplitude Cepheid V1334 Cyg A (pulsation period 3.3 days) for nearly 30 years. From these radial velocity data we have derived an orbit with a period of 5 years. From this orbit we have derived limits on the mass of the companion (V1334 Cyg C) of 3.1 to 4.4 M.. The system is also a marginally resolved visual binary with a much longer period that has been observed for nearly a century. We have used an IUE high-resolution spectrum to conclude that the hottest star in the system (V1334 Cyg B), which dominates the spectrum in the ultraviolet, is the wide companion, since the velocity is very near the systemic velocity. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Evans, NR (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 34 TC 12 Z9 12 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD JUN PY 2000 VL 119 IS 6 BP 3050 EP 3059 DI 10.1086/301397 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 335ET UT WOS:000088231100039 ER PT J AU Perola, GC Matt, G Fiore, F Grandi, P Guainazzi, M Haardt, F Maraschi, L Mineo, T Nicastro, F Piro, L AF Perola, GC Matt, G Fiore, F Grandi, P Guainazzi, M Haardt, F Maraschi, L Mineo, T Nicastro, F Piro, L TI BeppoSAX observations of Mrk 509 and MCG+8-11-11 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : individual : Mrk 509, MCG+8-11-11; galaxies : Seyfert X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; X-RAY-SPECTRUM; SEYFERT-1 GALAXIES; ACCRETION DISKS; EMISSION-LINE; ULTRAVIOLET; QUASARS; CONSTRAINTS; FEATURES; GINGA AB BeppoSAX observations of the Seyfert galaxies Mrk 509 and MCG +8-11-11 are presented. Earlier evidence of a soft excess in Mrk 509 is confirmed. This excess is found to be better represented by a power law than by a black body: with a photon slope Gamma(S) of 2.5, its extrapolation matches the flux recorded in the far UV. An ASCA observation, which appeared to exclude the presence of the excess while showing instead evidence of a warm absorber, turns out to be compatible with the coexistence of the excess seen with BeppoSAX and of the warm absorber. The hard power law of Mrk 509 is seen for the first time to be affected by a cut-off at high energies, with an e-folding energy of about 70 keV. Tn MCG +8-11-11 the cut-off is found at about 170 keV, consistent within the combined errors with a previous estimate from a ASCA+OSSE/CGRO observation. In both objects the reflection component is clearly detected. In Mrk 509 its strength, together with that of the iron K line, indicates a solid angle Omega, subtended by the reprocessing gas in the accretion disk, much less than 2 pi, but lacking a valid constraint on the inclination angle this evidence is not as convincing as that found with BeppoSAX in TC 4329A. In MCG +8-11-11 the same parameters are instead consistent with Omega=2 pi, but the comparison with an ASCA observation, when the flux level was about 2.5 times weaker, suggests that a substantial fraction of the angle might be associated with gas farther out than the accretion disk. C1 Univ Studi Roma Tre, Dipartimento Fis, I-00146 Rome, Italy. Osservatorio Astron Roma, I-00044 Frascati, Italy. CNR, Ist Astrofis Spaziale, I-00133 Rome, Italy. ESA, VILSPA, XMM SOC, Madrid 28080, Spain. Univ Insubria, Dipartimento Sci, I-22100 Como, Italy. Osservatorio Astron Brera, I-20121 Milan, Italy. CNR, Ist Fis Cosmica & Applicaz All Informat, I-90146 Palermo, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Perola, GC (reprint author), Univ Studi Roma Tre, Dipartimento Fis, Via Vasca Navale 84, I-00146 Rome, Italy. EM perola@fis.uniroma3.it RI PIRO, LUIGI/E-4954-2013; OI PIRO, LUIGI/0000-0003-4159-3984; Nicastro, Fabrizio/0000-0002-6896-1364; Mineo, Teresa/0000-0002-4931-8445; Fiore, Fabrizio/0000-0002-4031-4157 NR 36 TC 21 Z9 21 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD JUN PY 2000 VL 358 IS 1 BP 117 EP 124 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 333VK UT WOS:000088151300019 ER PT J AU Giannini, T Nisini, B Lorenzetti, D Di Giorgio, AM Spinoglio, L Benedettini, M Saraceno, P Smith, HA White, GJ AF Giannini, T Nisini, B Lorenzetti, D Di Giorgio, AM Spinoglio, L Benedettini, M Saraceno, P Smith, HA White, GJ TI Looking at the photon-dominated region in NGC 2024 through FIR line emission SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : formation; ISM : HII regions; ISM : individual; objects : NGC 3024; infrared : ISM : lines and bands ID LONG-WAVELENGTH SPECTROMETER; FAR-INFRARED SPECTROSCOPY; STAR-FORMING REGIONS; ISO-LWS OBSERVATIONS; MOLECULAR CLOUDS; PHOTODISSOCIATION REGIONS; ORION-B; PROTOSTELLAR CONDENSATIONS; DUST EMISSION; HERBIG AE AB We present the ISO-LWS spectra (45-200 mu m) of both the molecular cloud NGC 2024 and its associated HII region. We observed the two Class 0 objects FIR3 and FIR5 and the infrared source IRS2. All the spectra appear quite similar, with approximately the same strength high-J CO rotational lines (from J(np) =17 to J(up)=14), and atomic and ionic lines from oxygen, carbon and nitrogen. This uniformity suggests the bulk of the emission is from the extended cloud, and is not related to the local source conditions. The molecular emission has been modelled with a large velocity gradient (LVG) code, and the results imply that the emission originates in a clumpy, extended PDR with a temperature T similar to 100K and a density n(H2) similar to 10(6) cm(-3). CO column densities in excess of 10(18) cm(-2) are derived for this: molecular component. A line intensity ratio I([O I] 63 mu m)/I([O I] 145 mu m) of about 5 is found through all the region, indicating either that these two lines are both optically thick at the same temperature of CO, or, more likely, that the 63 mu m line is strongly absorbed by cold foreground gas. The ionised emission lines have been consistently modelled with CLOUDY; the lines arise from gas illuminated by an O9.5 star or its UV equivalent, representing the ionising capability of the whole OB cluster present in the region. From the intensity ratios of the ionic lines, relevant physical properties of the ionised gas (N/O abundance, electron density) are derived. C1 Osservatorio Astron Roma, I-00040 Monte Porzio Catone, Italy. Univ La Sapienza, Ist Astron, I-00161 Rome, Italy. CNR, Area Ric Tor Vergata, Ist Fis Spazio Interplanetario, I-00133 Rome, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ London Queen Mary & Westfield Coll, London E1 4NS, England. Stockholm Observ, S-13336 Saltsjobaden, Sweden. RP Giannini, T (reprint author), Osservatorio Astron Roma, Via Frascati 33, I-00040 Monte Porzio Catone, Italy. EM teresa@coma.mporzio.astro.it OI Giannini, Teresa/0000-0002-0224-096X; Spinoglio, Luigi/0000-0001-8840-1551; , Brunella Nisini/0000-0002-9190-0113 NR 54 TC 23 Z9 23 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD JUN PY 2000 VL 358 IS 1 BP 310 EP 320 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 333VK UT WOS:000088151300036 ER PT J AU Forbes, DA Masters, KL Minniti, D Barmby, P AF Forbes, DA Masters, KL Minniti, D Barmby, P TI The elliptical galaxy formerly known as the Local Group: merging the globular cluster systems SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : formation; Galaxy : halo; galaxies : star clusters; cosmology : observations; cosmology : early Universe ID HUBBLE-SPACE-TELESCOPE; AGE-METALLICITY RELATION; DWARF SPHEROIDAL GALAXY; SMALL-MAGELLANIC-CLOUD; STAR-CLUSTERS; INTERACTING GALAXIES; LMC CLUSTERS; MILKY-WAY; M31; PHOTOMETRY AB Prompted by a new catalogue of M31 globular clusters, we have collected together individual metallicity values for globular clusters in the Local Group. Although we briefly describe the globular cluster systems of the individual Local Group galaxies, the main thrust of our paper is to examine the collective properties. In this way we are simulating the dissipationless merger of the Local Group, into presumably an elliptical galaxy. Such a merger is dominated by the Milky Way and M31, which appear to be fairly typical examples of globular cluster systems of spiral galaxies. The Local Group 'Elliptical' has about 700 +/- 125 globular clusters, with a luminosity function resembling the 'universal' one. The metallicity distribution has peaks at [Fe/H] similar to -1.55 and -0.64 with a metal-poor to metal-rich ratio of 2.5: 1. The specific frequency of the Local Group Elliptical is initially about 1 but rises to about 3, when the young stellar populations fade and the galaxy resembles an old elliptical. The metallicity distribution and stellar population corrected specific frequency are similar to that of some known early type galaxies. Based on our results, we briefly speculate on the origin of globular cluster systems in galaxies. C1 Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. Swinburne Univ Technol, Hawthorn, Vic 3122, Australia. Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Santiago 22, Chile. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Forbes, DA (reprint author), Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. OI Masters, Karen/0000-0003-0846-9578 NR 75 TC 39 Z9 39 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD JUN PY 2000 VL 358 IS 2 BP 471 EP 480 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 334JE UT WOS:000088182700017 ER PT J AU van den Ancker, ME Tielens, AGGM Wesselius, PR AF van den Ancker, ME Tielens, AGGM Wesselius, PR TI ISO Spectroscopy of the young bipolar nebulae S106IR and Cep A East SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE shock waves; stars : circumstellar matter; stars : formation; ISM : HII regions; ISM : jets and outflows; infrared : stars ID INTERSTELLAR MOLECULAR-HYDROGEN; STAR-FORMING REGION; CEPHEUS-A; PHOTODISSOCIATION REGIONS; INFRARED OBSERVATIONS; WAVELENGTH SPECTROMETER; LABORATORY SIMULATIONS; LINE EMISSION; STELLAR WIND; FEATURES AB We present the results of ISO SWS and LWS grating scans towards the embedded Young Stellar Objects (YSOs) S106 IR and Cep A East. Emission from the pure rotational lines of H(2) and the infrared fine structure lines of [C II], [O I], [S I], [Si II] and [Fe II], as well as absorption bands due to H(2)O, CO and CO(2) ice were detected toward Cep A. In S106 we detected emission lines of H(2), CO, H I, and a large number of ionized species including Fe, O, N, C, Si, S, Ne and Ar. S106 also shows many of the infrared PAH bands in emission. Excitation temperatures and molecular hydrogen masses were derived from the low-lying pure rotational levels of Hz and are 500 and 730 K and 8 and 3 x 10(-3) M(.) for S106 and Cep A, respectively. Since both objects are expected to have several solar masses of H(2) in their environment, we conclude that in both cases the bulk of the H(2) is cooler than a few hundred Kelvins. Excitation temperatures and line ratios were compared with those predicted by theoretical models for PDRs and dissociative and non-dissociative shocks. The [S I] 25.2 mu m/[Si II] 34.8 mu m ratio is a particularly useful shock versus PDR discriminant and we conclude that S106 IR is dominated by PDR emission while Cep A East has a large shock component. From an analysis of the ionic lines in S106 we conclude that the central star must have a temperature around 37,000 K, corresponding to a spectral type of O8. From its luminosity it is concluded that the driving source of Cep A must also be a massive early-type star. The absence of strong high-ionization ionic lines in its ISO spectrum shows that Cep A has not yet created a significant H Ir region and must be younger than S106, illustrating the process of the clearing of the surroundings of a massive young star. C1 Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. SRON, NL-9700 AV Groningen, Netherlands. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP van den Ancker, ME (reprint author), Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. EM mario@astro.uva.nl NR 69 TC 51 Z9 51 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD JUN PY 2000 VL 358 IS 3 BP 1035 EP 1048 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 338MQ UT WOS:000088424200029 ER PT J AU Kochanek, CS Falco, EE Impey, CD Lehar, J McLeod, BA Rix, HW Keeton, CR Munoz, JA Peng, CY AF Kochanek, CS Falco, EE Impey, CD Lehar, J McLeod, BA Rix, HW Keeton, CR Munoz, JA Peng, CY TI The infrared Einstein ring in the gravitational lens MG J1131+0456 and the death of the dusty lens hypothesis SO ASTROPHYSICAL JOURNAL LA English DT Article DE dust, extinction; galaxies : individual (MG J1131+0456); galaxies : photometry; gravitational lensing; infrared : galaxies ID ELLIPTICAL GALAXIES; RADIO; MG-1131+0456; ABSORPTION; PHOTOMETRY; POPULATION; TELESCOPE; EMISSION; REDSHIFT; QUASARS AB We have obtained and modeled NICMOS images of the Einstein ring lens system MG J1131 + 0456, which show that its lens galaxy is an H = 18.6 mag, transparent, early-type galaxy at a redshift of z(l) similar or equal to 0.84; it has a major axis effective radius R-e = 0."7 +/- 0."1, projected axis ratio b/a = 0.6 +/- 0.1, and major axis P.A. = 55 degrees +/- 9 degrees. The lens is the brightest member of a group of at least seven galaxies with similar R-I and I-H colors, and the two closest group members produce sufficient tidal perturbations to explain the shape of the ring. The host galaxy of the MG J1131 + 0456 source is a z(s) greater than or similar to 2 extremely red object (ERO) that is lensed into optical and infrared rings of dramatically different morphologies. These differences imply a strongly wavelength-dependent source morphology that could be explained by embedding the host in a larger, dusty disk. At 1.6 mu m (H), the ring is spectacularly luminous, with a total observed flux of H = 17.4 mag and a demagnified flux of 19.3 mag, corresponding to a 1-2 L-* galaxy at the probable source redshift of z(s) greater than or similar to 2. Thus, it is primarily the stellar emission of the radio source host galaxy that produces the overall colors of two of the reddest radio lenses, MG J1131 + 0456 and JVAS B1938 + 666, aided by the suppression of optical active galactic nucleus emission by dust in the source galaxy. The dusty lens hypothesis - that many massive early-type galaxies with 0 less than or similar to z(l) less than or similar to 1 have large, uniform dust opacities - is ruled out. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Kochanek, CS (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 62 TC 20 Z9 21 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 1 PY 2000 VL 535 IS 2 BP 692 EP 705 DI 10.1086/308852 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 327HY UT WOS:000087789500017 ER PT J AU Wang, XH Loeb, A AF Wang, XH Loeb, A TI Variability of gamma-ray burst afterglows due to interstellar turbulence SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; turbulence ID COSMOLOGICAL FIREBALL MODEL; SMALL-SCALE STRUCTURE; RELATIVISTIC FIREBALLS; MOLECULAR CLOUDS; RADIO AFTERGLOW; GRB-990510; PARAMETERS; DYNAMICS; EMISSION; JET AB Gamma-ray burst (GRB) afterglows are commonly interpreted as synchrotron emission from a relativistic blast wave produced by a point explosion in an ambient medium, plausibly the interstellar medium of galaxies. We calculate the amplitude of flux fluctuations in the light curves of afterglows due to inhomogeneities in the surrounding medium. Such inhomogeneities are an inevitable consequence of interstellar turbulence but could also be generated by variability and anisotropy in a precursor wind from the GRB progenitor. Detection of their properties could provide important clues about the environments of GRB sources. We apply our calculations to GRB 990510, where an rms scatter of similar to 2% was observed for the optical flux fluctuations on the 0.1-2 hr timescale during the first day of the afterglow, consistent with it being due entirely to photometric noise. The resulting upper limits on the density fluctuations on scales of similar to 20-200 AU around the source of GRB 990510 are lower than the inferred fluctuation amplitude on similar scales in the Galactic interstellar medium. Hourly monitoring of future optical afterglows might therefore reveal fractional flux fluctuations at the level of a few percent. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Wang, XH (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 37 TC 55 Z9 55 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 1 PY 2000 VL 535 IS 2 BP 788 EP 797 DI 10.1086/308888 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 327HY UT WOS:000087789500025 ER PT J AU Aschwanden, MJ Tarbell, TD Nightingale, RW Schrijver, CJ Title, A Kankelborg, CC Martens, P Warren, HP AF Aschwanden, MJ Tarbell, TD Nightingale, RW Schrijver, CJ Title, A Kankelborg, CC Martens, P Warren, HP TI Time variability of the "quiet" Sun observed with TRACE. II. Physical parameters, temperature evolution, and energetics of extreme-ultraviolet nanoflares SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : chromosphere; Sun : corona; Sun : transition region; Sun : UV radiation ID SOLAR CORONA; ELEMENTAL ABUNDANCES; TRANSITION REGION; EMISSION MEASURE; HEATING EVENTS; FLARE; MICROFLARES; YOHKOH; ATMOSPHERE; LOOPS AB We present a detailed analysis of the geometric and physical parameters of 281 EUV nanoflares, simultaneously detected with the TRACE telescope in the 171 and 195 Angstrom wavelengths. The detection and discrimination of these flarelike events is detailed in the first paper in this series. We determine the loop length l, loop width w, emission measure EM, the evolution of the electron density n(e)(t) and temperature T-e(t), the hare decay time tau(decay), and calculate the radiative loss time tau(loss), the conductive loss time tau(cond), and the thermal energy E-th. The findings are as follows: (1) EUV nanoflares in the energy range of 10(24)-10(26) ergs represent miniature versions of larger flares observed in soft X-rays (SXR) and hard X-rays (HXR), scaled to lower temperatures (T-e less than or similar to 2 MK), lower densities (n(e) less than or similar to 10(9) cm(-3)), and somewhat smaller spatial scales (l approximate to 2-20 Mm). (2) The cooling time tau(decay) is compatible with the radiative cooling time tau(rad), but the conductive cooling timescale tau(cond) is about an order of magnitude shorter, suggesting repetitive heating cycles in time intervals of a few minutes. (3) The frequency distribution of thermal energies of EUV nanoflares, N(E) approximate to 10(-46)(E/10(24))(-1.8) (s(-1) cm(-2) ergs-l) matches that of SXR microflares in the energy range of 10(26)-10(29), and exceeds that of nonthermal energies of larger flares observed in HXR by a factor of 3-10 tin the energy range of 10(29)-10(32) ergs). Discrepancies of the power-law slope with other studies, which report higher values in the range of a = 2.0-2.6 (Krucker & Bent; Parnell & Jupp), are attributed to methodical differences in the detection and discrimination of EUV microflares, as well as to different model assumptions in the calculation of the electron density. Besides the insufficient power of nanoflares to heat the corona, we find also other physical limits for nanoflares at energies less than or similar to 10(24) ergs, such as the area coverage limit, the heating temperature limit, the lower coronal density limit, and the chromospheric loop height limit. Based on these quantitative physical limitations, it appears that coronal heating requires other energy carriers that are not luminous in EUV, SXR, and HXR. C1 Lockheed Martin Adv Technol Ctr, Solar & Astrophys Lab, Dept L941, Palo Alto, CA 94304 USA. Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Lockheed Martin Adv Technol Ctr, Solar & Astrophys Lab, Dept L941, Bldg 252,3251 Hanover St, Palo Alto, CA 94304 USA. EM aschwanden@lmsal.com NR 43 TC 207 Z9 209 U1 0 U2 5 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 2000 VL 535 IS 2 BP 1047 EP 1065 DI 10.1086/308867 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 327HY UT WOS:000087789500046 ER PT J AU Ferrarese, L Ford, HC Huchra, J Kennicutt, RC Mould, JR Sakai, S Freedman, WL Stetson, PB Madore, BF Gibson, BK Graham, JA Hughes, SM Illingworth, GD Kelson, DD Macri, L Sebo, K Silbermann, NA AF Ferrarese, L Ford, HC Huchra, J Kennicutt, RC Mould, JR Sakai, S Freedman, WL Stetson, PB Madore, BF Gibson, BK Graham, JA Hughes, SM Illingworth, GD Kelson, DD Macri, L Sebo, K Silbermann, NA TI A database of Cepheid distance moduli and tip of the red giant branch, globular cluster luminosity function, planetary nebula luminosity function, and surface brightness fluctuation data useful for distance determinations SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Review DE cosmology : theory; galaxies : distances and redshifts ID HUBBLE-SPACE-TELESCOPE; SCALE KEY PROJECT; H-II REGIONS; DWARF IRREGULAR GALAXY; ABSOLUTE PEAK BRIGHTNESS; VIRGO CLUSTER; STANDARD CANDLES; STELLAR POPULATIONS; SPIRAL GALAXIES; FORNAX CLUSTER AB We present a compilation of Cepheid distance moduli and data for four secondary distance indicators that employ stars in the old stellar populations: the planetary nebula luminosity function (PNLF), the globular cluster luminosity function (GCLF), the tip of the red giant branch (TRGB), and the surface brightness fluctuation (SBF) method. The database includes all data published as of 1999 July 15. The main strength of this compilation resides in the fact that all data are on a consistent and homogeneous system: all Cepheid distances are derived using the same calibration of the period-luminosity relation, the treatment of errors is consistent for all indicators, and measurements that are not considered reliable are excluded. As such, the database is ideal for comparing any of the distance indicators considered, or for deriving a Cepheid calibration to any secondary distance indicator, such as the Tully-Fisher relation, the Type Ia supernovae, or the fundamental plane for elliptical galaxies. This task has already been undertaken by Ferrarese et at, Sakai et al., Kelson et al., and Gibson et al. Specifically the database includes (1) Cepheid distances, extinctions, and metallicities; (2) reddened apparent lambda 5007 Angstrom magnitudes of the PNLF cutoff; (3) reddened apparent magnitudes and colors of the turnover of the GCLF (in both the V and B bands); (4) reddened apparent magnitudes of the TRGB (in the I band) and V-I colors at 0.5 mag fainter than the TRGB; and (5) reddened apparent surface brightness fluctuation magnitudes measured in Kron-Cousin I, K', and K-short, and using the F814W filter with the Hubble Space Telescope (HST) WFPC2. In addition, for every galaxy in the database we give reddening estimates from IRAS/DIRBE as well as H I maps, J2000 coordinates, Hubble and T-type morphological classification, apparent total magnitude in B, and systemic velocity. C1 CALTECH, Pasadena, CA 91125 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Australian Natl Univ, Res Sch Astron & Astrophys, Inst Adv Studies, Weston, ACT 2611, Australia. Natl Opt Astron Observ, Kitt Peak Natl Observ, Tucson, AZ 85726 USA. Carnegie Observ, Pasadena, CA 91101 USA. Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. NASA, IPAC, Extragalact Database, Pasadena, CA 91125 USA. CALTECH, Pasadena, CA 91125 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Royal Greenwich Observ, Cambridge CB3 0HA, England. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. RP Ferrarese, L (reprint author), CALTECH, Pasadena, CA 91125 USA. RI Gibson, Brad/M-3592-2015 OI Gibson, Brad/0000-0003-4446-3130 NR 182 TC 134 Z9 135 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD JUN PY 2000 VL 128 IS 2 BP 431 EP 459 PG 29 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 360QA UT WOS:000089677700002 ER PT J AU Macri, LM Huchra, JP Sakai, S Mould, JR Hughes, SMG AF Macri, LM Huchra, JP Sakai, S Mould, JR Hughes, SMG TI A database of Tully-Fisher calibrator galaxies SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE distance scale; galaxies : fundamental parameters galaxies : kinematics and dynamics; galaxies : photometry ID VELOCITY-FIELD; SURFACE PHOTOMETRY; SPIRAL GALAXIES; DISTANCE SCALE; LOCAL UNIVERSE; STANDARD STARS; CLUSTERS; CATALOG; H-0 AB We present BVRI surface photometry of spiral galaxies suitable for the absolute calibration of the Tully-Fisher relation. Galaxies were observed at the Fred L. Whipple Observatory (FLWO) 1.2 m, the Mount Stromlo and Siding Spring Observatory (MSSSO) 1 m, and the Cerro Tololo Inter-American Observatory (CTIO) 1.5 m telescopes from 1994 to 1999. The surface photometry measurements were carried out using the SFOTO package. We also present new derivations of 20% and 50% 21 cm line widths for most of these galaxies, based on existing profiles. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Res Sch Astron & Astrophy, Inst Adv Studies, Weston, ACT 2611, Australia. Univ Cambridge, Astron Inst, Cambridge CB3 0HA, England. RP Macri, LM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 32 TC 10 Z9 10 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD JUN PY 2000 VL 128 IS 2 BP 461 EP 468 DI 10.1086/313395 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 360QA UT WOS:000089677700003 ER PT J AU Buffa, G Tarrini, O Scappini, F Cecchi-Pestellini, C AF Buffa, G Tarrini, O Scappini, F Cecchi-Pestellini, C TI H(2)O-H(2)O collision rate coefficients SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE ISM : molecules; methods : numerical; molecular processes ID WATER AB H(2)O-H(2)O collision cross sections are calculated by adapting the method developed by Anderson and Tsao and Cornette for the calculation of collision broadening of molecular spectral lines. Cross sections are computed with a cutoff limit at 20 Angstrom(2) for the rotational levels of water with J less than or equal to 10 and E < 2000 cm-l in the temperature range 100-800 K. The accuracy of the calculated values is estimated to be 10%-20%. C1 Ist Nazl Fis Mat, I-56126 Pisa, Italy. CNR, Ist Spettroscopia Mol, I-40129 Bologna, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. RP Buffa, G (reprint author), Ist Nazl Fis Mat, Piazza Torricelli 2, I-56126 Pisa, Italy. OI Cecchi Pestellini, Cesare/0000-0001-7480-0324 NR 14 TC 9 Z9 9 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD JUN PY 2000 VL 128 IS 2 BP 597 EP 601 DI 10.1086/313389 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 360QA UT WOS:000089677700011 ER PT J AU Correll, DL Jordan, TE Weller, DE AF Correll, DL Jordan, TE Weller, DE TI Beaver pond biogeochemical effects in the Maryland Coastal Plain SO BIOGEOCHEMISTRY LA English DT Article DE ammonium; beavers; landscape; nitrate; phosphate; silicate; total organic-C; total organic-N; total organic-P; total suspended solids ID ADIRONDACK MOUNTAINS; CASTOR-CANADENSIS; STREAM; WETLAND AB The fluxes and concentrations of materials from two contiguous second-order watersheds in the Coastal Plain of Maryland, U.S.A. were measured for six years prior to and six years subsequent to the formation of a 1.25 ha beaver pond near the bottom of one of the watersheds. The watersheds have a clay aquiclude and were equipped with V-notch weirs and continuous volume-integrating water samplers. The beaver pond reduced annual discharge of water, total-N, total-P, dissolved silicate, TOC, and TSS by 8, 18, 21, 32, 28, and 27%, respectively. Most of the total-N reduction was due to increased retention of nitrate in the winter and spring and TON in the winter and summer. Most of the total-P reduction was the result of retention of both TPi and TOP in the winter and summer. Dissolved silicate retention peaked in the spring, while TOC and TSS retention peaked in the winter. Prior to the formation of the beaver pond, concentrations of TON, TPi, TOP, TOC, and TSS had highly significant correlations with stream discharge, especially in the winter, but subsequent to the pond there was little or no relationship between these concentrations and stream discharge. However, concentrations of nitrate in the spring and ammonium in the summer were highly correlated with stream discharge both before and after the formation of the beaver pond and regressions of discharge versus concentrations of these nutrients explained more of the variation in concentrations after the formation of the pond. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Correll, DL (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. OI Weller, Donald/0000-0002-7629-5437 NR 26 TC 32 Z9 36 U1 0 U2 15 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-2563 J9 BIOGEOCHEMISTRY JI Biogeochemistry PD JUN PY 2000 VL 49 IS 3 BP 217 EP 239 DI 10.1023/A:1006330501887 PG 23 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 297UV UT WOS:000086101800002 ER PT J AU Litvaitis, MK Bates, JW Hope, WD Moens, T AF Litvaitis, MK Bates, JW Hope, WD Moens, T TI Inferring a classification of the Adenophorea (Nematoda) from nucleotide sequences of the D3 expansion segment (26/28S rDNA) SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID PHYLOGENETIC ANALYSIS; FREELIVING NEMATODES; ADJOINING BIOTOPES; COASTAL DUNES; DANISH COASTS; ASCARIDOID NEMATODES; PHYLUM NEMATODA; 18S; GERMAN; PLATYHELMINTHES AB Nucleotide sequences of the D3 expansion segment of the 28S rDNA gene were used to reconstruct evolutionary relationships within the Adenophorea. Neighbor-joining and parsimony analyses of representatives of most major taxa revealed a paraphyletic Adenophorea (p = 0.0005). Within Adenophorea, the Enoplia, Enoplida, and Enoplina were paraphyletic (p = 0.0024, 0.0014, and 0.0120, respectively). A major division was evident within the Enoplida, with one lineage consisting of a basal Thoracostomopsidae and Enoplidae, and a second lineage consisting of Oncholaimidae and Encheliididae. Tripyloidina clustered close to the basal enoplid branch and formed a monophyletic taxon. Although appearing as paraphyletic in the maximum-parsimony and neighbor-joining trees, constraining Chromadoria and Chromadorida into monophyletic groups did not result in a longer tree. Within the Chromadoria, the order Desmodorida sensu Malakhov (1994) was paraphyletic. However, Desmodorida sensu Lorenzen (1994), which does not include Ceramonematidae, was monophyletic. Monhysterida formed a monophyletic order within Chromadoria, equivalent to Chromadorida and Desmodorida. The position of the Comesomatidae was tentatively identified among the Chromadorida, however, the possibility of their placement among the Monhysterida cannot be excluded completely. C1 Univ New Hampshire, Dept Zool, Durham, NH 03824 USA. Univ New Hampshire, Ctr Marine Biol, Durham, NH 03824 USA. Natl Museum Nat Hist, Smithsonian Inst, Washington, DC 20560 USA. State Univ Ghent, Dept Biol, Marine Biol Sect, Ghent, Belgium. RP Litvaitis, MK (reprint author), Univ New Hampshire, Dept Zool, Rudman Hll, Durham, NH 03824 USA. NR 62 TC 33 Z9 33 U1 0 U2 3 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 JUN PY 2000 VL 78 IS 6 BP 911 EP 922 DI 10.1139/cjz-78-6-911 PG 12 WC Zoology SC Zoology GA 327JL UT WOS:000087790700003 ER PT J AU Erwin, TL AF Erwin, TL TI Arboreal beetles of neotropical forests: Taxonomic supplement for the Agra virgata and Ohausi groups with a new species and additional distribution records (Coleoptera : Carabidae) SO COLEOPTERISTS BULLETIN LA English DT Article AB In the genus Agra, the virgata group is a circum-Amazonian-Middle American lineage, consists of 10 highly characteristic species that have a composite range extending from the tropics of Mexico to Bolivia, east as far as the Brazilian State of Goias. The majority of species are found on the periphery of the Amazon Basin, the rest in Middle America. Members of the virgata group and some brentid beetles (e.g., Arrhenodes gnatho (Licht.)) have similar bright and contrasting colors and elytral pattern and are sometimes found together. No connection or interaction between these two is known at present that could explain this similarity. Agra mime, new species, is described and attributed to the virgata group. The type locality is: Ecuador: Nape Province, 20 km east of Puerto Nape, Alinahui, 450 m,01 degrees 00'S, 077 degrees 25'W. A revised key and checklist of the virgata group species are provided. A map of all known localities for the 10 species in the group is provided. A general discussion is included of the new species, as well as biogeographical notes for 6 additional species for which new locality records were found (Agra vate, A. nola, A. virgata, A. chocha, A. phainops, A. imaginis). The ohausi group, a southeastern Brazil lineage, consists of 4 species. Here I report a new synonymy for A. ohausi Liebke (=Agra rugipunctata Straneo, n. syn.). C1 Smithsonian Inst, Museum Natl Hist Nat, Trop Forest Canpoy Lab, Megadivers Grp, Washington, DC 20560 USA. RP Erwin, TL (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Trop Forest Canpoy Lab, Megadivers Grp, Washington, DC 20560 USA. NR 9 TC 2 Z9 2 U1 1 U2 2 PU COLEOPTERISTS SOC PI NATCHEZ PA P.O. BOX 767, NATCHEZ, MS 39121 USA SN 0010-065X J9 COLEOPTS BULL JI Coleopt. Bull. PD JUN PY 2000 VL 54 IS 2 BP 251 EP 262 DI 10.1649/0010-065X(2000)054[0251:ABONFT]2.0.CO;2 PG 12 WC Entomology SC Entomology GA 340ZJ UT WOS:000088566300009 ER PT J AU Kaeppler, AL AF Kaeppler, AL TI Dance ethnology and the anthropology of dance SO DANCE RESEARCH JOURNAL LA English DT Article; Proceedings Paper CT 2000 Feet: a Celebration of World Dance Meeting CY JUN 23, 1999 CL PHILADELPHIA, PENNSYLVANIA C1 Smithsonian Inst, Washington, DC 20560 USA. RP Kaeppler, AL (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 73 TC 16 Z9 16 U1 0 U2 2 PU CONGRESS RESEARCH DANCE (CORD) PI BROCKPORT PA NEW YORK STATE UNIV, DEPT DANCE, COLLEGE BROCKPORT, BROCKPORT, NY 14420 USA SN 0149-7677 J9 DANCE RES J JI Dance Res. J. PD SUM PY 2000 VL 32 IS 1 BP 116 EP 125 DI 10.2307/1478285 PG 10 WC Dance SC Dance GA 341NB UT WOS:000088595500020 ER PT J AU Edsinger-Gonzales, E Dictus, WJAG van den Biggelaar, JAM AF Edsinger-Gonzales, E Dictus, WJAG van den Biggelaar, JAM TI The D-quadrant organizer in spiralian development SO DEVELOPMENTAL BIOLOGY LA English DT Meeting Abstract C1 Smithsonian Marine Stn, Ft Pierce, FL 34949 USA. Univ Utrecht, NL-3584 CH Utrecht, Netherlands. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0012-1606 J9 DEV BIOL JI Dev. Biol. PD JUN 1 PY 2000 VL 222 IS 1 MA 83 BP 236 EP 236 PG 1 WC Developmental Biology SC Developmental Biology GA 323AN UT WOS:000087542500098 ER PT J AU Greenberg, R Bichier, P Angon, AC MacVean, C Perez, R Cano, E AF Greenberg, R Bichier, P Angon, AC MacVean, C Perez, R Cano, E TI The impact of avian insectivory on arthropods and leaf damage in some Guatemalan coffee plantations SO ECOLOGY LA English DT Article DE antiherbivore defenses; Coffea arabica; exclosure experiment; food limitation; leaf damage; migratory birds ID BIRD PREDATION; SHADE COFFEE; FOREST; POPULATIONS; HYPOTHESIS; HABITATS; GROWTH; TOP AB Experimental work has established that vertebrates can have a large impact on the abundance of arthropods in temperate forest and grasslands, as well as on tropical islands. The importance of vertebrate insectivory has only rarely been evaluated for mainland tropical ecosystem. in this study, we used exclosures to measure the impact of birds on arthropods in Guatemalan coffee plantations. Variation in shade management on coffee farms provides a gradient of similar habitats that vary in the complexity of vegetative structure and floristics. We hypothesized that shaded coffee plantations, which support a higher abundance of insectivorous birds, would experience relatively greater levels of predation than would the sun coffee farms. We found a reduction (64-80%) in the number of large (> 5 mm in length) but not small arthropods in both coffee types which was consistent across most taxonomic groups and ecological guilds. We also found a small but significant increase in the frequency of herbivore damage on leaves in the exclosures. This level of predation suggests that birds may help in reducing herbivore numbers and is also consistent with food limitation for birds in coffee agroecosystems. However, the presence of shade did not have an effect on levels of insectivory. C1 Smithsonian Migratory Bird Ctr, Dept Zool Res, Washington, DC 20008 USA. Univ Valle Guatemala, Inst Invest, Guatemala City, Guatemala. RP Greenberg, R (reprint author), Smithsonian Migratory Bird Ctr, Dept Zool Res, Washington, DC 20008 USA. NR 38 TC 108 Z9 113 U1 8 U2 35 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 0012-9658 J9 ECOLOGY JI Ecology PD JUN PY 2000 VL 81 IS 6 BP 1750 EP 1755 DI 10.1890/0012-9658(2000)081[1750:TIOAIO]2.0.CO;2 PG 6 WC Ecology SC Environmental Sciences & Ecology GA 321FU UT WOS:000087446100022 ER PT J AU Litchman, E AF Litchman, E TI Growth rates of phytoplankton under fluctuating light SO FRESHWATER BIOLOGY LA English DT Article DE growth rate; phytoplankton; fluctuating light ID SHORT-TERM VARIATION; SKELETONEMA-COSTATUM; MARINE-PHYTOPLANKTON; OPTICAL-PROPERTIES; PHOTOSYNTHESIS; IRRADIANCE; ADAPTATION; PHOTOACCLIMATION; CHLOROPHYCEAE; PRODUCTIVITY AB 1. The effect of light fluctuations on the growth rates of four species of freshwater phytoplankton was investigated. Experimental light regimes included constant irradiance and fluctuations of a step function form, with equal proportion of high (maximum of 240 mu mol photons m(-2) s(-1)) and low light (minimum of 5 mu mol photons m(-2) s(-1)) (or dark) in a period. Fluctuations of 1, 8 and 24-h periods were imposed over several average irradiances (25, 50, 100 and 120 mu mol photons m(-2) s(-1)). 2. Growth rate responses to fluctuations were species-specific and depended on both the average irradiance and the period of fluctuations. Fluctuations at low average irradiances slightly increased growth rate of the diatom Nitzschia sp. and depressed growth of the cyanobacterium Phormidium luridum and the green alga Sphaerocystis schroeteri compared to a constant irradiance. 3. Fluctuations at higher average irradiance did not have a significant effect on the growth rates of Nitzschia sp. and Sphaerocystis schroeteri (fluctuations around saturating irradiances) and slightly increased the growth rates of the cyanobacteria Anabaena flosaquae and Phormidium luridum (when irradiance fluctuated between limiting and inhibiting levels). 4. In general, the effect of fluctuations tended to be greater when irradiance fluctuated between limiting and saturating or inhibiting levels of a species growth-irradiance curve compared to fluctuations within a single region of the curve. 5. The growth rates of species under fluctuating Light could not always be predicted from their growth-irradiance curves obtained under constant irradiance. When fluctuations occur between limiting and saturating or inhibiting irradiances for the alga and when the period of fluctuations is long (greater than 8 h), steady-state growth-irradiance curves may be insufficient to predict growth rates adequately. Consequently, additional data on physiological acclimation, such as changes in photosynthetic parameters, may be required for predictions under non-constant light supply in comparison to constant conditions. C1 Univ Minnesota, St Paul, MN 55108 USA. RP Litchman, E (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. EM litchman@serc.si.edu NR 50 TC 71 Z9 77 U1 5 U2 35 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0046-5070 J9 FRESHWATER BIOL JI Freshw. Biol. PD JUN PY 2000 VL 44 IS 2 BP 223 EP 235 DI 10.1046/j.1365-2427.2000.00559.x PG 13 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 328RR UT WOS:000087864300004 ER PT J AU Bogard, DD Garrison, DH McCoy, TJ AF Bogard, DD Garrison, DH McCoy, TJ TI Chronology and petrology of silicates from IIE iron meteorites: Evidence of a complex parent body evolution SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID RAY PRODUCTION-RATES; ORDINARY CHONDRITES; COSMOGENIC NUCLIDES; RB-87-SR-87 METHOD; OXYGEN-ISOTOPE; NOBLE-GASES; I-XE; AGES; ACHONDRITES; ORIGIN AB IIE iron meteorites contain silicate inclusions the characteristics of which suggest a parent body similar to that of H-chondrites. However, these silicates show a wide range of alteration, ranging from Netschaevo and Techado, the inclusions of which are little altered, to highly differentiated silicates like those in Kodaikanal, Weekeroo Station, and Colomera, which have lost metal and sulfur and are enriched in feldspar, We find these inclusions to show varying degrees of shock alteration. We made Ar-39-Ar-40 age determinations of Watson, Techado, Miles, Colomera, and Sombrerete. Watson has an Ar-Ar age of 3.677 +/- 0.007 Gyr, similar to previously reported ages for Kodaikanal and Netschaevo. We suggest that the various determined radiometric ages of these three meteorites were probably reset by a common impact event. The space exposure ages for these three meteorites are also similar to each other and are considerably younger than exposure ages of other IIEs, Ar-39-Ar-40 ages inferred for the other four meteorites analyzed are considerably older than Watson and are: Techado = 4.49 +/- 0.01 Gyr, Miles = 4.405 +/- 0.012 Gyr, Colomera = 4.470 +/- 0.010 Gyr, and Sombrerete = 4.541 +/- 0.0012 Gyr. These ages are in fair agreement with previously reported Rb-Sr isochron ages for Colomera and Weekeroo Station. Although several mechanisms to form IIE meteorites have been suggested, it is not obvious that a single mechanism could produce a suite of meteorites with very different degrees of silicate differentiation and with isotopic ages that differ by >0.8 Gyr. We suggest that those IIEs with older isotopic ages are a product of partial melting and differentiation within the parent body, followed by mixing of silicate and metal while both were relatively hot. Netschaevo and Watson may have formed by this same process or by impact mixing similar to 4.5 Gyr ago, but their isotopic ages may have been subsequently reset by shock heating. Kodaikanal apparently is required to have formed more recently, in which case impact melting and differentiation seems the only viable process. We see no compelling reasons to believe that IIE silicate and metal derived from different parent bodies or that the parent body of IIEs was the same as that of H-chondrites. Copyright (C) 2000 Elsevier Science Ltd. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Lockheed Martin Engn, Houston, TX 77058 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Mineral Sci, Washington, DC 20560 USA. RP Bogard, DD (reprint author), NASA, Lyndon B Johnson Space Ctr, SN2, Houston, TX 77058 USA. NR 76 TC 44 Z9 44 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD JUN PY 2000 VL 64 IS 12 BP 2133 EP 2154 DI 10.1016/S0016-7037(00)00355-0 PG 22 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 329WH UT WOS:000087931100009 ER PT J AU Ash-Milby, KE AF Ash-Milby, KE TI Reservation X: The power of place in Aboriginal contemporary art SO GREAT PLAINS QUARTERLY LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Indian, Washington, DC 20560 USA. RP Ash-Milby, KE (reprint author), Smithsonian Inst, Natl Museum Amer Indian, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU CENT GREAT PLAINS STUD PI LINCOLN PA UNIV NEBRASKA-LINCOLN 1214 OLDFATHER HALL, LINCOLN, NE 68588-0313 USA SN 0275-7664 J9 GREAT PLAINS QUART JI Gt. Plains Q. PD SUM PY 2000 VL 20 IS 3 BP 244 EP 245 PG 2 WC Humanities, Multidisciplinary SC Arts & Humanities - Other Topics GA 356DE UT WOS:000089428400018 ER PT J AU Gingerich, O AF Gingerich, O TI World-maps for finding the direction and distance to Mecca: Innovation and tradition in Islamic science. SO HISTORY OF SCIENCE LA English DT Book Review C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gingerich, O (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SCI HIST PUBL LTD PI BUCKS PA HALFPENNY FURZE MILL LANE CHALFONT ST GILES, BUCKS, ENGLAND HP8 4NR SN 0073-2753 J9 HIST SCI JI Hist. Sci. PD JUN PY 2000 VL 38 IS 120 BP 245 EP 247 PN 2 PG 3 WC History & Philosophy Of Science SC History & Philosophy of Science GA 323ZT UT WOS:000087596400007 ER PT J AU Nicholson, PD French, RG Tollestrup, E Cuzzi, JN Harrington, J Matthews, K Perkovic, O Stover, RJ AF Nicholson, PD French, RG Tollestrup, E Cuzzi, JN Harrington, J Matthews, K Perkovic, O Stover, RJ TI Saturn's rings I - Optical depth profiles from the 28 Sgr occultation SO ICARUS LA English DT Article DE planetary rings, Saturn; occultations ID PARTICLE-SIZE DISTRIBUTIONS; VOYAGER-1 RADIO OCCULTATION; F-RING; RESONANCE STRUCTURES; BENDING WAVES; B-RING; 28-SGR; FEATURES; IDENTIFICATION; WAVELENGTHS AB We present optical depth profiles for Saturn's rings at wavelengths of 0,9, 2.1, 3,3, and 3.9 mu m, obtained from the occultation of the star 28 Sgr on 3 July 1989 when the rings were near their maximum opening angle. The radial resolution of the data is similar to 18 km, as set by the angular diameter of the star. Very few, if any, structural changes are observed in the rings since the Voyager encounters in 1980/1981. Azimuthal variations in optical depth are restricted to the outermost part of the B Ring and to several previously known noncircular features. The mean optical depth in the heretofore unprobed central part of the B Ring is found to be 2.3 +/- 0.15 at 3.9 mu m. Quantitative comparisons of the optical depths with those measured by the Voyager PPS stellar occultation experiment at 0.27 mu m do reveal systematic differences between the major ring regions. In the C Ring, we find tau(28Sgr)/tau(PPS) similar or equal to 1.4, while in the B Ring and outer A Ring tau(28Sgr)/tau(PPS) similar or equal to 1.0. Only in the inner A Ring is tau(28Sgr) < tau(PPS) In agreement with previous studies at microwave and optical wavelengths, we conclude that there is very little evidence in the 28 Sgr data for a significant population of micrometer-sized particles anywhere in the main rings. Most of the observed variation in tau(28Sgr)/tau(PPS) can instead be attributed to variations in the particle size distribution in the rings in the centimeter to meter size range, which controls the angular width of the rings' forward-scattering cross section. This in turn controls the effective extinction efficiency for Earth-based occultation experiments, and thus the measured optical depth. In a companion paper we use these data to derive power-law models of the size distribution in each major ring region. (C) 2000 Academic Press. C1 Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Wellesley Coll, Dept Astron, Wellesley, MA 02481 USA. Harvard Univ, Ctr Astrophys, Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. CALTECH, Palomar Observ, Pasadena, CA 91125 USA. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. RP Nicholson, PD (reprint author), Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RI Harrington, Joseph/E-6250-2011; OI Harrington, Joseph/0000-0002-8955-8531 NR 60 TC 30 Z9 30 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2000 VL 145 IS 2 BP 474 EP 501 DI 10.1006/icar.2000.6356 PG 28 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 327KZ UT WOS:000087794200012 ER PT J AU Gurwell, MA Muhleman, DO AF Gurwell, MA Muhleman, DO TI CO on Titan: More evidence for a well-mixed vertical profile SO ICARUS LA English DT Article DE abundances; atmosphere; atmosphere, composition; radio observations; spectroscopy; Titan ID CARBON-MONOXIDE; HETERODYNE OBSERVATIONS; ATMOSPHERE; MILLIMETER; STRATOSPHERE; ABUNDANCE; MODELS AB We report new interferometric observations of the CO (2-1) rotational transition on Titan, We find that the spectrum is best fit by a uniform profile of 52 ppm, with estimated errors of 6 ppm (40 to 200 km) and 12 ppm (200 to 300 km). (C) 2000 Academic Press. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. RP Gurwell, MA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 24 TC 21 Z9 21 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2000 VL 145 IS 2 BP 653 EP 656 DI 10.1006/icar.2000.6424 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 327KZ UT WOS:000087794200028 ER PT J AU Vecchione, M Mickevich, WF Fauchald, K Collette, BB Williams, AB Munroe, TA Young, RE AF Vecchione, M Mickevich, WF Fauchald, K Collette, BB Williams, AB Munroe, TA Young, RE TI Importance of assessing taxonomic adequacy in determining fishing effects on marine biodiversity SO ICES JOURNAL OF MARINE SCIENCE LA English DT Article; Proceedings Paper CT ICES/SCOR Symposium on Ecosystem Effects of Fishing CY MAR 15-19, 1999 CL INST RECH DEV, MONTPELLIER, FRANCE SP ICES, SCOR HO INST RECH DEV DE marine biodiversity; natural resource management; systematics; taxonomy AB Fishing can change the biological diversity of an ecosystem substantially, and determining the effects of fishing on marine biodiversity requires a variety of data, chief among them the proper identification of organisms. Because identification of all organisms in an ecosystem is not currently possible, target taxonomic groups (taxa) must be selected. The current status of taxonomic information varies greatly among taxa and among geographic areas within taxa. Problems include nomenclature, diagnoses, and determination of taxonomic relationships. We provide examples of a variety of these problems. We then propose a series of criteria for evaluating available taxonomic information in determining the potential reliability of species identification, including recency and comprehensiveness of revisionary studies, methods used for systematic and phylogenetic studies, adequacy of documentation, and evidence of peer review. When the goal is to explore biodiversity, these criteria must be used differently from when measuring and monitoring biodiversity. (C) 2000 International Council for the Exploration of the Sea. C1 Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. Smithsonian Inst, Natl Museum Amer Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Univ Hawaii Manoa, Dept Oceanog, Honolulu, HI 96822 USA. RP Vecchione, M (reprint author), Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. NR 12 TC 18 Z9 19 U1 0 U2 5 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 1054-3139 J9 ICES J MAR SCI JI ICES J. Mar. Sci. PD JUN PY 2000 VL 57 IS 3 BP 677 EP 681 DI 10.1006/jmsc.2000.0707 PG 5 WC Fisheries; Marine & Freshwater Biology; Oceanography SC Fisheries; Marine & Freshwater Biology; Oceanography GA 346PL UT WOS:000088880200023 ER PT J AU Warner, D AF Warner, D TI Measuring the universe: Our historic quest to chart the horizons of space and time. SO ISIS LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Warner, D (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0021-1753 J9 ISIS JI Isis PD JUN PY 2000 VL 91 IS 2 BP 329 EP 329 DI 10.1086/384740 PG 1 WC History & Philosophy Of Science SC History & Philosophy of Science GA 343YA UT WOS:000088729400022 ER PT J AU Marvin, UB AF Marvin, UB TI The search for extraterrestrial life: Essays on science and technology. SO ISIS LA English DT Book Review C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Marvin, UB (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0021-1753 J9 ISIS JI Isis PD JUN PY 2000 VL 91 IS 2 BP 342 EP 343 DI 10.1086/384757 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA 343YA UT WOS:000088729400040 ER PT J AU Post, RC AF Post, RC TI The philosophy of railways: The transcontinental railway idea in British North America. SO ISIS LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Post, RC (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 2 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0021-1753 J9 ISIS JI Isis PD JUN PY 2000 VL 91 IS 2 BP 381 EP 382 DI 10.1086/384798 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA 343YA UT WOS:000088729400083 ER PT J AU Kidwell, PA AF Kidwell, PA TI Makin' numbers: Howard Aiken and the computer. SO ISIS LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Kidwell, PA (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0021-1753 J9 ISIS JI Isis PD JUN PY 2000 VL 91 IS 2 BP 405 EP 406 DI 10.1086/384821 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA 343YA UT WOS:000088729400113 ER PT J AU Kidwell, PA AF Kidwell, PA TI Howard Aiken: Portrait of a computer pioneer. SO ISIS LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Kidwell, PA (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0021-1753 J9 ISIS JI Isis PD JUN PY 2000 VL 91 IS 2 BP 406 EP 406 PG 1 WC History & Philosophy Of Science SC History & Philosophy of Science GA 343YA UT WOS:000088729400114 ER PT J AU Cucurull, L Navascues, B Ruffini, G Elosegui, P Rius, A Vila, J AF Cucurull, L Navascues, B Ruffini, G Elosegui, P Rius, A Vila, J TI The use of GPS to validate NWP systems: The HIRLAM model SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID GLOBAL POSITIONING SYSTEM; ATMOSPHERIC WATER-VAPOR; PRECIPITABLE WATER; RADIO INTERFEROMETRY; METEOROLOGY; ASSIMILATION; DELAY; GEODESY AB A meteorological synoptic situation using Global Positioning System (GPS) observations and a numerical weather prediction (NWP) model in the vicinity of the Madrid Sierra, Spain, between 2 and 15 December 1996 has been studied. The experiment was characterized by high precipitable water (PW) values associated to rainfall events. The PW was estimated at the level of 1 mm with five GPS receivers to study the passage of a winter frontal system. The GPS network had baselines ranging from 5 to 50 km. These observations have been used to study the spatial and temporal variations of PW For this same location and time period, PW calculations were carried out by HIRLAM (High-Resolution Limited Area Modeling), the hydrostatic NWP system operational at the Spanish National Weather Service. HIRLAM has been run in two modes: analysis (HIRLAM/A) and forecast (HIRLAM/F). The comparison of PW values obtained using GPS and high-resolution HIRLAM/A shows a PW bias of -0.4 mm (GPS-derived PW higher), and a root-mean-square (rms) difference of 2 mm (relative agreement of 85%), which is in agreement with the standard deviation of each method. A similar comparison between GPS and the high-resolution HIRLAM/F results in a bias and rms that increase when extending the forecast range up to a bias of -1.2 mm and an rms of 3 mm (relative agreement of 78%) for the longest forecast range studied, which is 24 h. Radiosonde profiles from a location near one of the sites of the GPS network have also been used to estimate PW. The PW bias and rms that result from comparing this data to the previous two methods are -1 and 1.6 mm (relative agreement of 88%) between GPS and radiosondes, and -1.2 and 1.3 mm (relative agreement of 90%) between radiosonde and HIRLAM/A. The PW estimated from GPS is probed to be an accurate measurement to validate NWP models. The study also shows that GPS measurements can detect small-scale fluctuations and therefore can be used to evaluate NWP models with finer resolution. C1 Inst Estud Espacials Catalunya, Barcelona 08034, Spain. Inst Nacl Meteorol, Madrid, Spain. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cucurull, L (reprint author), Inst Estud Espacials Catalunya, Edif Nexus-204,Gran Capita 2-4, Barcelona 08034, Spain. RI Vila, Jordi /B-4538-2010; Antonio, Rius/A-4873-2012; Cucurull, Lidia/E-8900-2015 OI Antonio, Rius/0000-0002-5947-2649; NR 35 TC 34 Z9 36 U1 0 U2 2 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 2000 VL 17 IS 6 BP 773 EP 787 DI 10.1175/1520-0426(2000)017<0773:TUOGTV>2.0.CO;2 PG 15 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 326XR UT WOS:000087763000003 ER PT J AU Lemaitre, R Reed, K AF Lemaitre, R Reed, K TI Raymond B. Manning: Biographical sketch and bibliography SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Biographical-Item C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Lemaitre, R (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU CRUSTACEAN SOC PI SAN ANTONIO PA 840 EAST MULBERRY, SAN ANTONIO, TX 78212 USA SN 0278-0372 J9 J CRUSTACEAN BIOL JI J. Crustac. Biol. PD JUN PY 2000 VL 20 IS 2 SI SI BP II EP XI PG 10 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 329AB UT WOS:000087883000001 ER PT J AU Tudge, CC Poore, GCB Lemaitre, R AF Tudge, CC Poore, GCB Lemaitre, R TI Preliminary phylogenetic analysis of generic relationships within the Callianassidae and Ctenochelidae (Decapoda : Thalassinidea : Callianassoidea) SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article ID GHOST SHRIMP; SOUTH FLORIDA; PACIFIC COAST; BRAZIL CRUSTACEA; CARIBBEAN COAST; GENUS; REEXAMINATION; COLOMBIA; LEPIDOPHTHALMUS; NEOCALLICHIRUS AB A phylogenetic analysis of 106 representatives in the thalassinidean families Ctenochelidae and Callianassidae, based on 93 adult morphological characters, was performed to investigate the interrelationships between the 25 currently recognized genera. The callianideid, Callianidea typa H. Milne Edwards, was used as the out-group. The two in-group families, Ctenochelidae and Callianassidae. were both shown to be monophyletic. Monophyly of the four ctenochelid subfamilies (Anacalliacinae, Callianopsinae, Ctenochelinae, and the recently suggested Gourretinae) was not supported. Three callianassid subfamilies (Callianassinae, Cheraminae, and Eucalliacinae) were found to be monophyletic but with species compositions different from those presently understood. The fourth callianassid subfamily (Callichirinae) is paraphyletic and ancestral to the other subfamilies. Several species described as species of Callianassa s.l. were found to belong to other genera, Recent diagnosis of several small genera from the Americas and Japan has left larger traditional genera such as Callianassa s.l, and Cheramus paraphyletic. Glypturus is apparently paraphyletic as presently diagnosed. The taxonomic position of some species remains enigmatic largely because of missing data. A listing of all valid genera and species of Ctenochelidae and Callianassidae at the time of publication is provided. C1 Victoria & Albert Museum, Crustacea Lab, Melbourne, Vic 3001, Australia. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Tudge, CC (reprint author), Victoria & Albert Museum, Crustacea Lab, POB 666E, Melbourne, Vic 3001, Australia. NR 100 TC 58 Z9 67 U1 0 U2 2 PU CRUSTACEAN SOC PI SAN ANTONIO PA 840 EAST MULBERRY, SAN ANTONIO, TX 78212 USA SN 0278-0372 J9 J CRUSTACEAN BIOL JI J. Crustac. Biol. PD JUN PY 2000 VL 20 IS 2 SI SI BP 129 EP 149 PG 21 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 329AB UT WOS:000087883000015 ER PT J AU Lin, FJ Kensley, B Chan, TY AF Lin, FJ Kensley, B Chan, TY TI The rare axiid genus Oxyrhynchaxius Parisi, 1917 (Decapoda : Thalassinidea), with a description of a new species from Australia SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article AB Recent discovery of a specimen of Oxyrhynchaxius Parisi, 1917, from Taiwan led to a survey of the material of this rare and monotypic axiid genus deposited at various museums. Other than the type, five specimens of this genus from Japan, Taiwan, Hong Kong, and Australia were found and can be separated into two forms. Those from Japan to Hong Kong are large in size, have slender eyes and bear a dorsal carina on the posterior carapace but lack a median carina on the abdomen. The Australian specimens are small, have stout eyestalks and bear a median carina on the abdomen but lack a middorsal carina on the posterior carapace. The specimens from Japan to Hong Kong probably all belong to O. japonicus Parisi, 1917. The Australian material, though probably juvenile, represents a distinct species and is described as new. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Natl Taiwan Ocean Univ, Grad Sch Fisheries Sch, Keelung, Taiwan. Natl Taiwan Ocean Univ, Inst Marine Biol, Keelung, Taiwan. RP Kensley, B (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 5 TC 7 Z9 9 U1 0 U2 0 PU CRUSTACEAN SOC PI SAN ANTONIO PA 840 EAST MULBERRY, SAN ANTONIO, TX 78212 USA SN 0278-0372 J9 J CRUSTACEAN BIOL JI J. Crustac. Biol. PD JUN PY 2000 VL 20 IS 2 SI SI BP 199 EP 206 PG 8 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 329AB UT WOS:000087883000021 ER PT J AU Kensley, B Lin, FJ Yu, HP AF Kensley, B Lin, FJ Yu, HP TI Further records of thalassinidean shrimps from Taiwan (Decapoda : Axiidae and Calocartdidae), with descriptions of three new species SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article ID CRUSTACEA AB Three axiid species and one calocaridid are recorded from Taiwan. The three deepwater species are described as new: Calaxius manningi, having a finely pitted carapace and strongly spinose chelipeds; Calocarides chani, which possesses finely tuberculate first chelipeds; and Ambiaxius foveolatus, which has a shallowly pitted carapace branchiostegite. Neaxius acanthus (A. Milne Edwards) is recorded from the coral reefs of Taiwan. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Natl Taiwan Ocean Univ, Grad Sch Fisheries Sci, Keelung, Taiwan. RP Kensley, B (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 12 TC 12 Z9 15 U1 1 U2 1 PU CRUSTACEAN SOC PI SAN ANTONIO PA 840 EAST MULBERRY, SAN ANTONIO, TX 78212 USA SN 0278-0372 J9 J CRUSTACEAN BIOL JI J. Crustac. Biol. PD JUN PY 2000 VL 20 IS 2 SI SI BP 207 EP 217 PG 11 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 329AB UT WOS:000087883000022 ER PT J AU Lemaitre, R Campos, NH AF Lemaitre, R Campos, NH TI Porcellana lillyae, new species (Decapoda, Anomura, Porcellanidae), from the Caribbean Sea, with a key to the western Atlantic species of the genus SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article AB A new species of porcelain crab, Porcellana lillyae, from the continental shelf of the Caribbean coast of Colombia, is described. This new species, the fourth of the genus Porcellana Lamarck currently recognized from the western Atlantic, is most similar to P. sigsbeiana A. Milne-Edwards. The new species is distinguished primarily by the dentate condition of the frontal and lateral margins of the carapace and the presence of spines on the ventral margin of the rostrum. The new species is compared with P. sigsbeiana, and a key to aid in identification of western Atlantic species of the genus is presented. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. INVEMAR, Univ Nacl, Inst Ciencias Nat Colombia, Santa Marta, Colombia. RP Lemaitre, R (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 20 TC 4 Z9 4 U1 0 U2 0 PU CRUSTACEAN SOC PI SAN ANTONIO PA 840 EAST MULBERRY, SAN ANTONIO, TX 78212 USA SN 0278-0372 J9 J CRUSTACEAN BIOL JI J. Crustac. Biol. PD JUN PY 2000 VL 20 IS 2 SI SI BP 259 EP 265 PG 7 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 329AB UT WOS:000087883000028 ER PT J AU Williams, AB Smith, CR Baco, AR AF Williams, AB Smith, CR Baco, AR TI New species of Paralomis (Decapoda, Anomura, Lithodidae) from a sunken whale carcass in the San Clemente Basin off southern California SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article AB Paralomis manningi, new species, is described and illustrated from two immature males recovered from remains of a whale carcass sunken at a depth of 1,922 m in the San Clemente Basin off southern California. While studying the ecology of whale-fall communities on the California margin with the aid of a remotely operated vehicle, we (CRS and ARE) collected the lithodid specimens from the organic-rich axial skeleton of an 11.7-m long juvenile gray whale, Eschrichtius robustus (Lilljeborg, 1861), that had been experimentally placed at the San Clemente floor for 39 months. In general outline of body, spination, and other ornamentation, the new species seems most closely related to four species of Paralomis that were described and figured by Macpherson (1988): P. pectinata Macpherson, P, serrata Macpherson, P. cristulata Macpherson, and P. africana Macpherson. The closest resemblance is to P. cristulata. A key to identification of these species is abridged from Macpherson (1988). Five species of squat lobsters, Galatheidae, were associated with the whale skeleton; Munidopsis cascadia Ambler, M. yaquiensis Ambler, M. verrilli Benedict, M, quadrata Faxon, and a possibly undescribed species of Munidopsis. C1 Univ Hawaii, Dept Oceanog, Honolulu, HI 96822 USA. Smithsonian Inst, Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. RP Smith, CR (reprint author), Univ Hawaii, Dept Oceanog, 1000 Pope Rd, Honolulu, HI 96822 USA. NR 10 TC 5 Z9 6 U1 0 U2 2 PU CRUSTACEAN SOC PI SAN ANTONIO PA 840 EAST MULBERRY, SAN ANTONIO, TX 78212 USA SN 0278-0372 J9 J CRUSTACEAN BIOL JI J. Crustac. Biol. PD JUN PY 2000 VL 20 IS 2 SI SI BP 281 EP 285 PG 5 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 329AB UT WOS:000087883000030 ER PT J AU Bishop, GA Williams, AB AF Bishop, GA Williams, AB TI Fossil crabs from Tepee Buttes, submarine seeps of the Late Cretaceous Pierre Shale, South Dakota and Colorado, USA SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article ID BIOLOGICAL COMMUNITIES; HYDROTHERMAL VENTS; SUBDUCTION ZONE; DEEP-SEA; DECAPODA; PACIFIC; CARBONATES; CRUSTACEA; SLOPE; FAUNA AB Tepee Buttes are low conical hills which occur in scattered clusters along the strike of the Late Cretaceous Pierre Shale near Pueblo, Colorado, and around the Black Hills of South Dakota, Montana, and Wyoming. These erosional landforms develop around resistant columnar limestone masses thought to have been deposited by warm, methane-rich, submarine springs within relatively homogeneous, less resistant claystones. Origin of the Tepee Buttes is attributed to dewatering of underlying claystones. The submarine springs provided a unique habitat on the Western Interior Cretaceous sea bottom for growth of large populations of the lucinid bivalve, Nymphalucina occidentalis, often preserved in living position in reef-like masses encircling the spring vents. Concentration of abundant biomass immediately around the spring vents formed the basis of communities preserved as the Nymphalucina Assemblage dominated by N. occidentalis, but including ammonoid cephalopods, other bivalved mollusks, gastropods, foraminiferans, and a few decapod crustaceans. Fragments of grounded fossilized gymnosperm and angiosperm wood riddled with Teredo borings are also found on the vent cores. Twenty specimens of decapod crustaceans representing three new species of crabs were collected from Tepee Buttes near Oelrichs and Newell, South Dakota, and collecting near Pueblo, Colorado, yielded specimens belonging to three new species, as well as one specimen of Hoplitocarcinus punctatus. The new taxa include Heus foersteri, new genus and species, Raninella manningi, new species (family Raninidae), and Plagiophthalmus bjorki, new species (family Prosopidae). Descriptions, illustrations, and comparisons of new taxa with previously described members of the family are given. C1 Georgia So Univ, Dept Geol & Geog, Statesboro, GA 30460 USA. Smithsonian Inst, Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. RP Bishop, GA (reprint author), Georgia So Univ, Dept Geol & Geog, Statesboro, GA 30460 USA. NR 90 TC 13 Z9 13 U1 1 U2 7 PU CRUSTACEAN SOC PI SAN ANTONIO PA 840 EAST MULBERRY, SAN ANTONIO, TX 78212 USA SN 0278-0372 J9 J CRUSTACEAN BIOL JI J. Crustac. Biol. PD JUN PY 2000 VL 20 IS 2 SI SI BP 286 EP 300 PG 15 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 329AB UT WOS:000087883000031 ER PT J AU Morton, ES Stutchbury, BJM AF Morton, ES Stutchbury, BJM TI Demography and reproductive success in the Dusky Antbird, a sedentary tropical passerine SO JOURNAL OF FIELD ORNITHOLOGY LA English DT Article ID BIRDS; TERRITORIALITY AB Demographic data are presented from an 8-yr study of a marked population of the Dusky Antbird (Cercomacra tyrannina), a sedentary neotropical passerine with year-long territories and pairbonds. Dusky Antbirds had an annual survival rate of 82%, and the survivorship curve was linear. Sexes did not differ in survival. The probability of reproducing successfully, based on the number of pairs accompanied by independent young the following dry season, was only 8% and no territory produced more than one successful nest, if any. In one year (1997) reproduction was significantly better (25%) than the other years, perhaps associated with lowered predation during an extremely dry wet season. We suggest that for Dusky Antbirds, a species with no extra-pair mating behavior, a long adult lifespan appears to be the primary means to increase lifetime reproductive success. C1 Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. York Univ, Dept Biol, Toronto, ON M3J 1PE, Canada. RP Morton, ES (reprint author), Natl Zool Pk, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. NR 21 TC 19 Z9 19 U1 2 U2 14 PU ASSOC FIELD ORNITHOLOGISTS PI STATESBORO PA GEORGIA SOUTHERN UNIV, DEPT BIOLOGY, STATESBORO, GA 30460-8042 USA SN 0273-8570 J9 J FIELD ORNITHOL JI J. Field Ornithol. PD SUM PY 2000 VL 71 IS 3 BP 493 EP 500 PG 8 WC Ornithology SC Zoology GA 366XT UT WOS:000090032100015 ER PT J AU Woo, R Habbal, SR AF Woo, R Habbal, SR TI Connecting the Sun and the solar wired: Source regions of the fast wind observed in interplanetary space SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SCINTILLATION OBSERVATIONS; ACTIVITY MINIMUM; STREAMER BELT; CORONAL HOLE; SPEED; LATITUDE; CYCLE; DEPENDENCE; EVOLUTION; SLOW AB Highly sensitive radio occultation and white light measurements of path-integrated density have shown that the solar corona comprises three distinct morphological regions, streamer, quiet Sun, and polar coronal hole, which except for the streamer region, extend radially into interplanetary space from 1.15 R(s) to at least 30 R(s). In this paper we build on these results by comparing solar wind flow speeds observed at the same time as path-integrated density. Flow speeds are inferred from the Doppler dimming of O VI lines with the ultraviolet coronagraph spectrometer on the Solar and Heliospheric Observatory, while the simultaneous polarized brightness measurements of path-integrated density are from the High Altitude Observatory Mauna Loa Mk III K-coronamerer. The comparison of global flow speed and density observations in 1997 produces three new results. First, it shows, that the three distinct morphological regions, identified earlier in density measurements, are present in the latitudinal profile of the flow speed in the corona. In particular, the flow speed measurements provide evidence for the quiet Sun as an additional source of fast wind. Second, the comparison shows that flow spend and density are anticorrelated in the solar corona. Third, it demonstrates that the Mk III pB measurements can readily serve as a proxy for velocity distribution in the outer corona. The extensive Mk III data set that spans nearly two solar cycles therefore provides the framework of near-Sun measurements with which connections with solar wind measurements in interplanetary space can be made. Specifically, we show that fast wind regions in the heliosphere, observed directly by Ulysses and Wind plasma measurements and remotely by Nagoya interplanetary scintillation measurements, map radially back to fast wind regions at the Sun identified by the Mk III data. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Woo, R (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM richard.woo@jpl.nasa.gov NR 41 TC 11 Z9 11 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 2000 VL 105 IS A6 BP 12667 EP 12674 DI 10.1029/1999JA000255 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 319QD UT WOS:000087351900011 ER PT J AU Summers, K Holmes, K Boag, P AF Summers, K Holmes, K Boag, P TI DNA fingerprinting in Minyobates minutus, the minute poison frog SO JOURNAL OF HERPETOLOGY LA English DT Article ID CARE; DENDROBATIDAE; EVOLUTION; POLYGYNY; ANURA; COST C1 E Carolina Univ, Dept Biol, Greenville, NC 27858 USA. Smithsonian Trop Res Inst, Balboa, Panama. Queens Univ, Dept Biol, Kingston, ON K7L 3N6, Canada. RP Summers, K (reprint author), E Carolina Univ, Dept Biol, Greenville, NC 27858 USA. EM summersk@mail.ecu.edu RI Boag, Peter/B-2907-2014 OI Boag, Peter/0000-0003-0050-2089 NR 18 TC 0 Z9 0 U1 0 U2 2 PU SOC STUDY AMPHIBIANS REPTILES PI ST LOUIS PA C/O ROBERT D ALDRIDGE, ST LOUIS UNIV, DEPT BIOLOGY, 3507 LACLEDE, ST LOUIS, MO 63103 USA SN 0022-1511 J9 J HERPETOL JI J. Herpetol. PD JUN PY 2000 VL 34 IS 2 BP 310 EP 313 DI 10.2307/1565433 PG 4 WC Zoology SC Zoology GA 318WH UT WOS:000087307300023 ER PT J AU Newman, LJ Norenburg, JL Reed, S AF Newman, LJ Norenburg, JL Reed, S TI Taxonomic and biological observations on the tiger flatworm, Maritigrella crozieri (Hyman, 1939), new combination (Platyhelminthes, Polycladida, Euryleptidae) from Florida waters SO JOURNAL OF NATURAL HISTORY LA English DT Article DE Platyhelminthes; Polycladida; euryleptidae; hypodermic insemination; feeding; Florida AB The tiger flatworm, Maritigrella crozieri (Hyman, 1939) (Platyhelminthes, Polycladida, Cotylea) new combination, is redescribed from eastern Florida and the Florida Keys. This marine flatworm is one of the most common polyclads within warm temperate to tropical west Atlantic, yet it has been misidentified consistently as a pseudocerotid. Animals were kept alive in the laboratory for 3 weeks for biological observations. Findings indicated that these euryleptids employ hypodermic insemination, with multiple copulations occurring over several days. Sperm was transferred in sperm bundles bilaterally with little apparent damage to the epidermis of the copulating worms. Copulation sessions were variable and lasted an average of 15.4 min. In situ and laboratory observations indicated that M. crozieri fed exclusively on the mangrove ascidian Ecteinascidia turbinata Herdman, 1880, an individual consuming one prey zooid in an average of 17 min and an average of 19 zooids over 24 h. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Smithsonian Marine Stn, Ft Pierce, FL 34946 USA. RP Newman, LJ (reprint author), Univ Sunshine Coast, Fac Sci, Locked Bag 4, Macoochydone DO, Qld 4558, Australia. RI Norenburg, Jon/K-3481-2015 OI Norenburg, Jon/0000-0001-7776-1527 NR 17 TC 20 Z9 20 U1 0 U2 7 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0022-2933 J9 J NAT HIST JI J. Nat. Hist. PD JUN PY 2000 VL 34 IS 6 BP 799 EP 808 DI 10.1080/002229300299264 PG 10 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 320JH UT WOS:000087397700001 ER PT J AU Grissom, C AF Grissom, C TI Mount-making for museum objects SO JOURNAL OF THE AMERICAN INSTITUTE FOR CONSERVATION LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Grissom, C (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 2 PU AMER INST CONSERVATION HISTORIC ARTISTIC WORKS PI WASHINGTON PA 1717 K ST, NW, STE 301, WASHINGTON, DC 20006 USA SN 0197-1360 J9 J AM INST CONSERV JI J. Am. Inst. Conserv. PD SUM PY 2000 VL 39 IS 2 BP 280 EP 282 PG 3 WC Humanities, Multidisciplinary SC Arts & Humanities - Other Topics GA 355VD UT WOS:000089408500009 ER PT J AU Sallum, MAR Forattini, OP Wilkerson, RC AF Sallum, MAR Forattini, OP Wilkerson, RC TI Redescription of the adult and larva and first description of the pupa of Anopheles (Kerteszia) laneanus SO JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION LA English DT Article DE Anopheles; Kerteszia; Anopheles (Kerteszia) laneanus; redescription; taxonomy ID SCANNING ELECTRON-MICROSCOPY; CULICIDAE; DIPTERA; EGGS AB Anopheles (Kerteszia) laneanus is redescribed and compared with other species of the subgenus Kerteszia. The pupal stage is described for the 1st time and information on bionomics is provided. C1 Univ Sao Paulo, Fac Saude Publ, Dept Epidemiol, BR-01246904 Sao Paulo, Brazil. Smithsonian Inst, Dept Entomol, Walter Reed Biosystemat Unit, Museum Support Ctr,MRC 534,Natl Museum Nat Hist, Washington, DC 20560 USA. RP Sallum, MAR (reprint author), Univ Sao Paulo, Fac Saude Publ, Dept Epidemiol, Ave Dr Arnaldo 715, BR-01246904 Sao Paulo, Brazil. RI Sallum, Maria/B-8537-2012 NR 20 TC 4 Z9 4 U1 0 U2 0 PU AMER MOSQUITO CONTROL ASSOC PI MOUNT LAUREL PA 15000 COMMERCE PARKWAY, SUITE C, MOUNT LAUREL, NJ 08054 USA SN 8756-971X EI 1943-6270 J9 J AM MOSQUITO CONTR JI J. Am. Mosq. Control Assoc. PD JUN PY 2000 VL 16 IS 2 BP 86 EP 92 PG 7 WC Entomology SC Entomology GA 324YR UT WOS:000087650000005 PM 10901631 ER PT J AU Kaeppler, AL AF Kaeppler, AL TI Maori art and culture, 2nd edition. SO JOURNAL OF THE POLYNESIAN SOCIETY LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Kaeppler, AL (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 1 U2 1 PU POLYNESIAN SOC INC PI AUCKLAND PA C/O UNIV AUCKLAND, DEPT ANTHROPOLOGY, PRIVATE BAG, AUCKLAND 92019, NEW ZEALAND SN 0032-4000 J9 J POLYNESIAN SOC JI J. Polyn. Soc. PD JUN PY 2000 VL 109 IS 2 BP 209 EP 211 PG 3 WC Anthropology SC Anthropology GA 323RM UT WOS:000087578800008 ER PT J AU Kaeppler, AL AF Kaeppler, AL TI Queen Salote of Tonga: The story of an era 1900-1965. SO JOURNAL OF THE POLYNESIAN SOCIETY LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Kaeppler, AL (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU POLYNESIAN SOC INC PI AUCKLAND PA C/O UNIV AUCKLAND, DEPT ANTHROPOLOGY, PRIVATE BAG, AUCKLAND 92019, NEW ZEALAND SN 0032-4000 J9 J POLYNESIAN SOC JI J. Polyn. Soc. PD JUN PY 2000 VL 109 IS 2 BP 213 EP 215 PG 3 WC Anthropology SC Anthropology GA 323RM UT WOS:000087578800010 ER PT J AU Glynn, PW Colley, SB Ting, JH Mate, JL Guzman, HM AF Glynn, PW Colley, SB Ting, JH Mate, JL Guzman, HM TI Reef coral reproduction in the eastern Pacific: Costa Rica, Panama and Galapagos Islands (Ecuador). IV. Agariciidae, recruitment and recovery of Pavona varians and Pavona sp.a SO MARINE BIOLOGY LA English DT Article ID TROPICAL PACIFIC; RED-SEA; TEMPERATURE; VARIABILITY; MORTALITY; ANNULARIS; HAWAII; EVENT AB The reproductive ecology of two eastern Pacific zooxanthellate coral species was examined as part of a continuing series of studies relating bleaching/mortality events caused by the El Nino-Southern Oscillation disturbance, and is described for study sites in Costa Rica, Panama, and the Galapagos Islands (Ecuador). This study deals with the sibling agariciid species Pavona varians and Pavona sp.a over a 13 yr period (1985 to 1997). Both pavona species are broadcast-spawners with some gonochoric, but mostly sequential hermaphroditic colonies. Minimum colony sizes (and ages) at first reproduction were 5 cm (5 yr) and 3 cm (2 to 3 yr), respectively, in P. varians and Pavona sp.a. In the Panama and Galapagos populations, gonochoric colonies spawn eggs or sperm at least monthly. Six fecundity attributes were not significantly different in the two species, but the eggs of P. varians are white to beige and positively buoyant, and those of Pavona sp.a are dark green and neutrally to negatively buoyant. Eggs of both species lack zooxanthellae. Both species are reproductively active year-round, with maximum activity in the dry season in the nonupwelling Gulf of Chiriqui, and in the wet season in the upwelling Gulf of Panama. Spawning is predominantly during full moon, and possibly also at new moon at most study sites. Spawning in P. varians and Pavona sp.a is 12 h out of phase, with the former species spawning similar to 1h before sunrise and the latter about 1h after sunset. The fecundity of Pavona spp. at Cano and the Galapagos Islands was much greater (19900 to 27900 eggs cm(-2) yr(-1)) than at all Panama sites (14800 to 19800 eggs cm(-2) yr(-1)). Intraspecific crosses in both species resulted in swimming planula larvae after 25 to 36 h. Recruitment of P. varians was highest in Panama, moderate in Costa Rica, and nil in the Galapagos Islands, matching, respectively, the contributions of P. varians to the pre-1982/1983 El Nino coral-population abundances in these areas. Recruitment success of P. varians at Uva Island was significantly related to maximum monthly positive sea surface-temperature (SST) anomalies that occurred in the year preceding recruitment over the period 1982 to 1996; recruitment failed when SST anomalies exceeded 1.6 to 1.9 C degrees during the severe ENSO events of 1983/1983 and 1997/1998. C1 Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine Biol & Fisheries, Miami, FL 33149 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Glynn, PW (reprint author), Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine Biol & Fisheries, 4600 Rickenbacker Causeway, Miami, FL 33149 USA. NR 59 TC 35 Z9 39 U1 3 U2 22 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD JUN PY 2000 VL 136 IS 5 BP 785 EP 805 DI 10.1007/s002270000286 PG 21 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 334KR UT WOS:000088186100005 ER PT J AU Fornshell, JA AF Fornshell, JA TI Variability of the Florida Current offshore from Fort Pierce Florida as revealed by satellite imagery SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article ID SPIN-OFF EDDIES AB The western boundary of the Florida Current is distinguished from the inshore waters by a sharp rise in sea surface temperature. Its movements were studied using satellite imagery for a period of fifty one days from January 21, 1998 to March 13, 1998. The Florida Current made five incursions inshore of its mean position during this period. This dynamic activity is ecologically important because the Florida Current represents a major source of nutrients for primary productivity in the region. The satellite data were compared to data from NORA surface buoys to insure accuracy. C1 Smithsonian Inst, Dept Invertebrate Zool, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Fornshell, JA (reprint author), Smithsonian Inst, Dept Invertebrate Zool, Natl Museum Nat Hist, Washington, DC 20560 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 USA SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD SUM PY 2000 VL 34 IS 2 BP 34 EP 37 PG 4 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 345XD UT WOS:000088839700005 ER PT J AU Shurgalin, M Parkinson, WH Yoshino, K Schoene, C Lapatovich, WP AF Shurgalin, M Parkinson, WH Yoshino, K Schoene, C Lapatovich, WP TI Precision measurements of sodium-sodium and sodium-noble gas molecular absorption SO MEASUREMENT SCIENCE AND TECHNOLOGY LA English DT Article DE absorption cell; molecular absorption; anomalous dispersion method; Czerny-Turner spectrograph; CCD; Mach-Zender interferometer; spectroscopy ID HIGH-TEMPERATURE; LINE; WINGS AB The experimental apparatus and measurement technique are described for precision absorption measurements in sodium-noble gas mixtures. The absolute absorption coefficient is measured in the wavelength range from 425 nm to 760 nm with +/-2% uncertainty and spectral resolution of 0.02 nm. The precision is achieved by using a specially designed absorption cell with an accurately defined absorption path length, low noise CCD detector and double-beam absorption measurement scheme. The experimental set-up and the cell design details are given. Measurements of sodium atomic number density with +/-5% uncertainty complement absorption coefficient measurements and allow derivation of the reduced absorption coefficients for certain spectral features. The sodium atomic number density is measured using the anomalous dispersion method. The accuracy of this method is improved by employing a least-squares fit to the interference image recorded with a CCD detector and the details of this technique are given. The measurements are aimed at stringent testing of theoretical calculations and improving the values of molecular parameters used in calculations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. OSRAM Sylvania Lighting Res, Beverly, MA 01915 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 14, Cambridge, MA 02138 USA. NR 24 TC 11 Z9 11 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-0233 EI 1361-6501 J9 MEAS SCI TECHNOL JI Meas. Sci. Technol. PD JUN PY 2000 VL 11 IS 6 BP 730 EP 737 DI 10.1088/0957-0233/11/6/316 PG 8 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 325VH UT WOS:000087696800020 ER PT J AU Hershkovitz, MA Zimmer, EA AF Hershkovitz, MA Zimmer, EA TI Ribosomal DNA evidence and disjunctions of western American Portulacaceae SO MOLECULAR PHYLOGENETICS AND EVOLUTION LA English DT Article DE Portulacaceae; rDNA; disjunction; dispersal; biogeography ID RESTRICTION-SITE VARIATION; INTERNAL TRANSCRIBED SPACERS; PHYLOGENETIC-RELATIONSHIPS; MONTIOPSIS PORTULACACEAE; MOLECULAR EVOLUTION; MORPHOLOGICAL DATA; CLADISTIC-ANALYSIS; SEQUENCES; BIOGEOGRAPHY; RDNA AB Phylogenetic analysis of ribosomal DNA internal transcribed spacer sequences from 35 members of western American Portulacaceae plus seven Portulacaceae outgroups generally supports morphologically based interpretations of multiple intercontinental disjunctions. The data neither support nor refute monophyly of the western American group but strongly support a group comprising the western American taxa plus Phemeranthus, the only strictly American genus of the morphology-based eastern American/African group of Portulacaceae, along with the Australian genus Parakeelya. Support is strong for the monophyly of Calandrinia, Montiopsis, Lewisia, Claytonia, and Montia, along with a sister relationship of the last two. The data neither strongly support nor refute the morphologically based diagnosis of Cistanthe, but they strongly support a clade including the North American Cistanthe section Calyptridium and the South American Cistanthe sections Amarantoideae and Philippiamra. The internal transcribed spacer data fail to resolve the phylogenetic relationships among most of the western American lineages, suggesting either rapid radiation or, alternatively, erratic evolution of the internal transcribed spacer. The internal transcribed spacer and morphological evidence together suggest that in this group there have been 8-13 dispersal and colonization events across >2000 km (1 for every 15-26 extant species in this group). The internal transcribed spacer data document complex molecular evolutionary patterns, including strong substitution biases, among-site rate heterogeneity, positional bias for deamination-type substitutions, nonstationarity, and variable rates of insertion/deletion. Our phylogenetic conclusions, however, do not appear to be sensitive to these patterns, (C) 2000 Academic Press. C1 Smithsonian Inst, Lab Mol Systemat, Washington, DC 20560 USA. RP Hershkovitz, MA (reprint author), Univ Chile, Fac Ciencias, Dept Biol, Casilla 653, Santiago, Chile. RI Zimmer, Elizabeth/G-3890-2011 NR 96 TC 27 Z9 30 U1 0 U2 7 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1055-7903 EI 1095-9513 J9 MOL PHYLOGENET EVOL JI Mol. Phylogenet. Evol. PD JUN PY 2000 VL 15 IS 3 BP 419 EP 439 DI 10.1006/mpev.1999.0720 PG 21 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 328KM UT WOS:000087850100009 PM 10860651 ER PT J AU Spindler, RE Pukazhenthi, BS Wildt, DE AF Spindler, RE Pukazhenthi, BS Wildt, DE TI Oocyte metabolism predicts the development of cat embryos to blastocyst in vitro SO MOLECULAR REPRODUCTION AND DEVELOPMENT LA English DT Article DE cytoplasmic; meiotic; maturation; blastocyst; autocrine; paracrine ID PREIMPLANTATION MOUSE EMBRYOS; FOLLICLE-STIMULATING-HORMONE; MATURED IN-VITRO; INNER CELL MASS; DOMESTIC CAT; ENERGY-METABOLISM; BOVINE EMBRYOS; INVITRO FERTILIZATION; MEIOTIC MATURATION; CULTURE CONDITIONS AB Current methods for detecting complete oocyte maturation and developmental competence are inadequate. The objectives of this study were to (1) examine the relationship between cat oocyte energy metabolism and development in vitro after fertilization and (2) determine if cumulus cell metabolism could be used to predict development of individual oocytes after fertilization in vitro. The hanging drop method was used to assess metabolism of three different types of cat oocytes: immature (IMO), in vitro matured (IVM), and in vivo matured (IVOM). Stage of oocyte nuclear maturation or developmental competence was assessed after metabolic analysis, Glycolysis and oxidation of glucose, glutamine, palmitate, and lactate increased with the resumption of oocyte meiotic maturation (P < 0.05). Pyruvate was the preferred substrate, but uptake was not linked to maturation. IVM oocytes had impaired glucose and palmitate metabolism compared to IVOM oocytes (P < 0.05). Oocyte glycolytic activity and oocyte glucose oxidation correlated well with embryo development after insemination in vitro (P < 0.05). Furthermore, oocytes that had similar glucose metabolism and that were grouped together for culture on this basis had higher (P < 0.05) overall rates of development than oocytes grouped randomly. There was no correlation (P > 0.05) between cumulus cell metabolism and individual oocyte development after in vitro fertilization. The data reveal that energy metabolism is linked to oocyte maturation in the cat and that glucose metabolic activity can indicate those oocytes most likely to fertilize and develop in vitro. Measuring cumulus cell metabolism does not accurately predict individual oocyte development after insemination in vitro. Mel. Reprod. Dev. 56:163-171, 2000. (C) 2000 Wiley-Liss, Inc. C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Spindler, RE (reprint author), Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. NR 74 TC 72 Z9 75 U1 1 U2 10 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1040-452X J9 MOL REPROD DEV JI Mol. Reprod. Dev. PD JUN PY 2000 VL 56 IS 2 BP 163 EP 171 DI 10.1002/(SICI)1098-2795(200006)56:2<163::AID-MRD7>3.0.CO;2-3 PG 9 WC Biochemistry & Molecular Biology; Cell Biology; Developmental Biology; Reproductive Biology SC Biochemistry & Molecular Biology; Cell Biology; Developmental Biology; Reproductive Biology GA 311FT UT WOS:000086874600007 PM 10813848 ER PT J AU Gomez, JF Trapero, J Pascual, S Patel, N Morales, C Torrelles, JM AF Gomez, JF Trapero, J Pascual, S Patel, N Morales, C Torrelles, JM TI Ammonia observations of the nearby molecular cloud MBM 12 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE stars : formation; ISM : clouds; ISM : individual : MBM 12; ISM : molecules; radio lines : ISM ID OUTFLOW; L1457; CORE; GAS AB We present NH3(1,1) and (2,2) observations of MBM 12, the closest known molecular cloud (65-pc distance), aimed at finding evidence for on-going star formation processes, No local temperature (with a T-rot upper limit of 12 K) or linewidth enhancement is found, which suggests that the area of the cloud that we have mapped (similar to 15-arcmin size) is not currently forming stars. Therefore this nearby 'starless' molecular gas region is an ideal laboratory to study the physical conditions preceding new star formation. A radio continuum source has been found in Very Large Array archive data, close to but outside the NH3 emission. This source is likely to be a background object. C1 INTA, Lab Astrofis Espacial & Fis Fundamental, E-28080 Madrid, Spain. Univ SEK, E-40003 Segovia, Spain. Univ Complutense, Dept Astrofis, E-28040 Madrid, Spain. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CSIC, IEEC, E-08034 Barcelona, Spain. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. RP Gomez, JF (reprint author), INTA, Lab Astrofis Espacial & Fis Fundamental, Apdo Correos 50727, E-28080 Madrid, Spain. RI Gomez, Jose Francisco/D-8392-2016; OI Gomez, Jose Francisco/0000-0002-7065-542X; Torrelles, Jose Maria/0000-0002-6896-6085 NR 16 TC 2 Z9 2 U1 0 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JUN 1 PY 2000 VL 314 IS 4 BP 743 EP 746 DI 10.1046/j.1365-8711.2000.03346.x PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 321XJ UT WOS:000087480300011 ER PT J AU Mair, RW Hoffmann, D Sheth, SA Wong, GP Butler, JP Patz, S Topulos, GP Walsworth, RL AF Mair, RW Hoffmann, D Sheth, SA Wong, GP Butler, JP Patz, S Topulos, GP Walsworth, RL TI Reduced xenon diffusion for quantitative lung study - the role of SF6 SO NMR IN BIOMEDICINE LA English DT Article DE xenon; diffusion; sulfur hexafluoride; restricted diffusion; pulsed gradient spin echo; PGSE; gas-diffusion NMR ID SPIN RELAXATION; GAS-DIFFUSION AB The large diffusion coefficients of gases result in significant spin motion during the application of gradient pulses that typically last a few milliseconds in most NMR experiments. In restricted environments, such as the lung, this rapid gas diffusion can lead to violations of the narrow pulse approximation, a basic assumption of the standard Stejskal-Tanner NMR method of diffusion measurement. We therefore investigated the effect of a common, biologically inert buffer gas, sulfur hexafluoride (SF6), on Xe-129 NMR and diffusion. We found that the contribution of SF6 to Xe-129 T-1 relaxation in a 1:1 xenon/oxygen mixture is negligible up to 2 bar of SF6 at standard temperature. We also measured the contribution of SF6 gas to Xe-129 T-2 relaxation, and found it to scale inversely with pressure, with this contribution approximately equal to 1 s for 1 bar SF6 pressure and standard temperature. Finally, we found the coefficient of Xe-129 diffusion through SF6 to be approximately 4.6 x 10(-6) m(2)s(-1) for 1 bar pressure of SF6 and standard temperature, which is only 1.2 times smaller than the Xe-129 self diffusion coefficient for 1 bar Xe-129 pressure and standard temperature. From these measurements we conclude that SF6 will not sufficiently reduce Xe-129 diffusion to allow accurate surface-area/volume ratio measurements in human alveoli using time-dependent gas diffusion NMR. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Sch Publ Hlth, Dept Environm Hlth, Boston, MA 02115 USA. Brigham & Womens Hosp, Dept Radiol, Boston, MA 02115 USA. Harvard Univ, Sch Med, Boston, MA 02115 USA. Brigham & Womens Hosp, Dept Anaesthesia, Boston, MA 02115 USA. RP Mair, RW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 59, Cambridge, MA 02138 USA. RI Patz, Samuel/I-2879-2012 NR 20 TC 10 Z9 10 U1 0 U2 2 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0952-3480 J9 NMR BIOMED JI NMR Biomed. PD JUN PY 2000 VL 13 IS 4 BP 229 EP 233 DI 10.1002/1099-1492(200006)13:4<229::AID-NBM637>3.0.CO;2-S PG 5 WC Biophysics; Radiology, Nuclear Medicine & Medical Imaging; Spectroscopy SC Biophysics; Radiology, Nuclear Medicine & Medical Imaging; Spectroscopy GA 331AW UT WOS:000087995700010 PM 10867701 ER PT J AU Sklenar, P Robinson, H AF Sklenar, P Robinson, H TI Two new species in Oritrophium and Floscaldasia (Asteraceae : Astereae) from the High Andes of Ecuador SO NOVON LA English DT Article AB Two new species from the family Asteraceae, tribe Astereae, were collected during botanical investigations in the Ecuadorian Andes. Oritrophium llanganatense Sklenar & H. Robinson and Floscaldasia ozorelloides Sklenar & H. Robinson are here described and illustrated. Oritrophium llanganatense is distinct from other species of the genus by a combination of abaxially lanate leaves with outer phyllaries narrowly ovate to oblong. Floscaldasia azorelloides differs from the other species of the genus by its three-lobed leaves. The two species inhabit the upper superparamo and are restricted to remote areas of the Ecuadorian Eastern Cordillera. C1 Charles Univ, Dept Bot, Prague 12801 2, Czech Republic. US Natl Herbarium, Natl Museum Nat Hist, Smithsonian Inst, Washington, DC 20560 USA. RP Sklenar, P (reprint author), Charles Univ, Dept Bot, Benatska 2, Prague 12801 2, Czech Republic. NR 9 TC 5 Z9 6 U1 0 U2 0 PU MISSOURI BOTANICAL GARDEN PI ST LOUIS PA 2345 TOWER GROVE AVENUE, ST LOUIS, MO 63110 USA SN 1055-3177 J9 NOVON JI Novon PD SUM PY 2000 VL 10 IS 2 BP 144 EP 148 DI 10.2307/3393015 PG 5 WC Plant Sciences SC Plant Sciences GA 331BY UT WOS:000087998500014 ER PT J AU Novotny, V Basset, Y AF Novotny, V Basset, Y TI Rare species in communities of tropical insect herbivores: pondering the mystery of singletons SO OIKOS LA English DT Article ID RAIN-FOREST; BODY LENGTH; ABUNDANCE; DIVERSITY; RICHNESS; NUMBER; RARITY; FICUS; FAUNA; TREES AB The host specificity, taxonomic composition and feeding guild of rare species were studied in communities of herbivorous insects in New Guinea. Leaf-chewing and sap-sucking insects (Orthoptera, Phasmatodea, Coleoptera, Lepidoptera and Hemiptera-Auchenorrhyncha) were sampled from 30 species of trees and shrubs (15 spp. of Ficus, Moraceae, six spp. of Macaranga and nine species of other Euphorbiaceae) in a lowland rain forest. Feeding trials were performed with all leaf-chewers in order to exclude transient species. Overall, the sampling produced 80062 individuals of 1050 species. The species accumulation curve did not attain an asymptote, despite 950 person-days of sampling. Rare species, defined as those found as single individuals, remained numerous even in large samples and after the exclusion of transient: non-feeding species. There was no difference among plant species in the proportion of rare species in their herbivore communities, which was, on average, 45%. Likewise, various herbivore guilds and laxa had ail very similar proportions of rare and common species. There was also no difference between rare and common species in their host specificity. Both highly specialised species and generalists, feeding on numerous plants, contributed to the singleton records on particular plant species. predominantly, a species was rare on a particular host whilst more common on other, often related, host species, or relatively rare on numerous other host plants, so that its aggregate population was high. Both cases are an example of the "mass effect", since it is probable that such rare species were dependent on a constant influx of immigrants from the other host plants. These other plants were found particularly often among congeneric plants, less so among confamilial plants from different genera and least frequently among plants from different families. There were also 278 very rare species, found as one individual on a single plant species, only. Their host specificity could not be assessed; they might have been either very rare specialists, or species feeding also on other plants, those that were not studied. The former possibility is unlikely since monophagous species, collected as singletons at the present sampling effort, would have existed at an extremely low population density less than 1 individual per 10 ha of the forest. C1 Univ S Bohemia, Inst Entomol CAS, CZ-37005 Ceske Budejovice, Czech Republic. Univ S Bohemia, Fac Biol, CZ-37005 Ceske Budejovice, Czech Republic. Smithsonian Trop Res Inst, Balboa, Ancon, Panama. RP Novotny, V (reprint author), Univ S Bohemia, Inst Entomol CAS, Branisovska 31, CZ-37005 Ceske Budejovice, Czech Republic. RI Basset, Yves/B-6642-2014; Novotny, Vojtech/G-9434-2014 OI Novotny, Vojtech/0000-0001-7918-8023 NR 48 TC 273 Z9 286 U1 10 U2 56 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0030-1299 J9 OIKOS JI Oikos PD JUN PY 2000 VL 89 IS 3 BP 564 EP 572 DI 10.1034/j.1600-0706.2000.890316.x PG 9 WC Ecology SC Environmental Sciences & Ecology GA 318PR UT WOS:000087293400016 ER PT J AU Barth, AJ Shields, JC AF Barth, AJ Shields, JC TI LINER/H II "transition" nuclei and the nature of NGC 4569 SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID HOPKINS-ULTRAVIOLET-TELESCOPE; WOLF-RAYET; STAR-FORMATION; COMPOSITE SPECTRA; GALACTIC-CENTER; HII-REGIONS; MILKY-WAY; GALAXIES; EMISSION; STARBURST AB Motivated by the discovery of young, massive stars in the nuclei of some LINER/H II "transition" nuclei such as NGC 4569, we have computed photoionization models to determine whether some of these objects may be powered solely by young star clusters rather than by accretion-powered active nuclei. The models were calculated with the photoionization code CLOUDY, using evolving starburst continua generated by the STARBURST99 code of C. Leitherer and coworkers. We find that the models are able to reproduce the emission-line spectra of transition nuclei, but only for instantaneous bursts of solar or higher metallicity, and only for ages of similar to 3-5 Myr, the period when the extreme-ultraviolet continuum is dominated by emission from Wolf-Rayet stars. For clusters younger than 3 Myr or older than 6 Myr, and for models with a constant star formation rate, the softer ionizing continuum results in an emission spectrum more typical of H II regions. This model predicts that Wolf-Rayet emission features should appear in the spectra of transition nuclei. While such features have not generally been detected to date, they could be revealed in observations having higher spatial resolution. Demographic arguments suggest that this starburst model may not apply to the majority of transition nuclei, particularly those in early-type host galaxies, but it could account for some members of the transition class in hosts of type Sa and later. The starburst models during the Wolf-Rayet-dominated phase can also reproduce the narrow-line spectra of some LINERs, but only under conditions of above-solar metallicity and only if high-density gas is present (n(e) greater than or similar to 10(5) cm(-3)). This scenario could be applicable to some "Type 2" LINERs which do not show any clear signs of nonstellar activity. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Ohio Univ, Dept Phys & Astron, Clippinger Labs 251B, Athens, OH 45701 USA. RP Barth, AJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM abarth@cfa.harvard.edu; shields@helios.phy.ohiou.edu NR 75 TC 56 Z9 56 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD JUN PY 2000 VL 112 IS 772 BP 753 EP 767 DI 10.1086/316583 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 328PE UT WOS:000087858600003 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI Encyclopedia of archaeology: The great archaeologists. SO REFERENCE & USER SERVICES QUARTERLY LA English DT Book Review C1 Smithsonian Inst Lib, Washington, DC 20560 USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Lib, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER LIBRARY ASSOC PI CHICAGO PA 50 E HURON ST, CHICAGO, IL 60611 USA SN 1094-9054 J9 REF USER SERV Q JI Ref. User Serv. Q. PD SUM PY 2000 VL 39 IS 4 BP 408 EP 408 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 348BV UT WOS:000088965200030 ER PT J AU Takahashi, M Nowicke, JW Webster, GL Orli, SS Yankowski, S AF Takahashi, M Nowicke, JW Webster, GL Orli, SS Yankowski, S TI Pollen morphology, exine structure, and systematics of Acalyphoideae (Euphorbiaceae), part 3 tribes Epiprineae (Epiprinus, Symphyllia, Adenochlaena, Cleidiocarpon, Koilodepas, Cladogynos, Cephalocrotonopsis, Cephalocroton, Cephalomappa), Adelieae (Adelia, Crotonogynopsis, Enriquebeltrania, Lasiocroton, Leucocroton), Alchorneae (Orfilea, Alchornea, Coelebogyne, Aparisthmium, Bocquillonia, Conceveiba, Gavarretia), Acalypheae pro parte (Ricinus, Adriana, Mercurialis, Leidesia, Dysopsis, Wetria, Cleidion, Sampantaea, Macaranga) SO REVIEW OF PALAEOBOTANY AND PALYNOLOGY LA English DT Article DE Acalyphoideae; exine structure; pollen; systematics AB This is the third paper of an extensive study of pollen morphology and exine structure of Acalyphoideae (Euphorbiaceae) following the most recent system of Webster. Pollen from 120 collections representing 96 species and 30 genera is described and illustrated with light microscopy, scanning and transmission electron microscopy. These taxa are from tribes Epiprineae, Adelieae, Alchorneae, and Acalypheae pro parte. Pollen of eight genera, Epiprinus, Symphyllia, Adenochlaena, Cleidiocarpon, Koilodepas, Cladogynos, Cephalocrotonopsis and Cephalocroton, of the nine assigned to Epiprinae share 3-colporate apertures, microreticulate, punctate or deeply punctate tecta, well developed or prominent columellae (Koilodepas excepted) and thin foot layers; pollen of the ninth genus, Cephalomappa, has porelike colpi, a coarsely reticulate exine, irregular columellae and an irregular foot layer. Of the five genera assigned to Adelieae, pollen of Adelia, Lasiocroton and Leucocroton is similar: 3-colp(oroid)ate with stratified opercula, crotonoid tecta and thin foot layers; grains of Enriquebeltrania and Crotonogynopsis lack opercula and the latter has a distinctive infratectum of poorly differentiated columellae. Ail genera examined of tribe Alchorneae, seven of the nine, have exines with unstratified opercula and elongated columellae near the endoaperture. Exines of subtribe Alchorneinae (Orfilea, Alchornea, Coelebogyne, Aparisthmium, Bocquillonia) have complex infratecta of poorly differentiated columellae, whereas pollen of Conceveiba and Gavarretia, the two genera examined of the three assigned to subtribe Conceveibinae, has a single layer of short columellae and almost identical tectal morphology, In the large tribe Acalypheae, pollen of the first six of the 11 subtribes was examined. Pollen of Ricinus (Ricininae) and Adriana (Adrianinae) share indistinguishable exine structures and tecta. Pollen of Mercurialis and Leidesia of subtribe Mercurialinae and pollen of Dysopsis of subtribe Dysopsidinae are almost identical: finely reticulate tecta, very thin apertural endexines, elongate columellae, and channeled/perforate foot layers. All three genera of subtribe Cleidiinae have grains that are 3-colporate and have complete tecta; pollen of Wetria has a tectum morphology very similar to that of Ricinus and Adriana; pollen of Cleidion is 3-brevicolporate with microrugulose or punctate tecta, and has threadlike non-apertural endexines and foot layers, and thick tecta; exines of Sampantaea have an endexine throughout the grain, thin foot layers, very short columellae and a thick continuous tectum. Pollen of Macaranga of subtribe Macaranginae is small, 3-colporate with poorly defined endoapertures, and an exine structure characterized by thin foot layers, short columellae, and thick tecta. Pollen data support: the concept of the subtribe Epiprininae, but indicate that subtribe Cephalomappinae (Cephalomappa) is not related and should be considered for separate tribal status; a close relationship among Adelia, Lasiocroton and Leucocroton, but not with the two remaining members of Adelieae, Enriquebeltrania and Crotonogynopsis, which do not appear to be closely related to each other; the present concept of Alchorneae and subtribes Alchorneinae and Conceveibinae. Within the genera examined of the first six subtribes of Acalypheae, the pollen data: support a close relationship between the monogeneric subtribes Ricininae and Adrianinae; indicate a close relationship between subtribes Mercurialinae (Mercurialis, Leidesia) and Dysopsidinae (Dysopsis); suggest that Wetria is not closely related to Cleidion or Sampantaea (Cleidiinae); tentatively support the concept of Macaranginae as comprising only Macaranga. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Smithsonian Inst, Dept Bot, Natl Museum Nat Hist, Washington, DC 20560 USA. Kagawa Univ, Dept Biol, Takamatsu, Kagawa 7608522, Japan. Univ Calif Davis, Plant Biol Sect, Herbarium, Davis, CA 95616 USA. RP Nowicke, JW (reprint author), Smithsonian Inst, Dept Bot, Natl Museum Nat Hist, NHB 166, Washington, DC 20560 USA. EM nowickej@nmnh.si.edu NR 15 TC 25 Z9 25 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0034-6667 J9 REV PALAEOBOT PALYNO JI Rev. Palaeobot. Palynology PD JUN PY 2000 VL 110 IS 1-2 BP 1 EP 66 DI 10.1016/S0034-6667(99)00061-5 PG 66 WC Plant Sciences; Paleontology SC Plant Sciences; Paleontology GA 342LQ UT WOS:000088646400001 ER PT J AU Cordero, RAS AF Cordero, RAS TI Effect of two natural light regimes and nutrient addition on the forest herb Begonia decandra (Begoniaceae) SO REVISTA DE BIOLOGIA TROPICAL LA English DT Article DE Begonia; biomass allocation; canopy gaps; Puerto Rico; plant mortality; understory herb ID TROPICAL RAIN-FOREST; TREE SEEDLINGS; PHOTOSYNTHESIS; RESPONSES; PLANTS; GROWTH; AVAILABILITY; ACCLIMATION AB The effect of two natural light-growing conditions (understory versus light gaps) and the interaction with nutrient availability (through fertilization) were studied in the understory herb Begonia decandra, in the Luquillo Experimental Forest in Puerto Rico. Sixteen potted plants obtained from cuttings were randomly chosen and distributed in each of eighth forest environments (four light gaps and four understories), for a total of 128 plants. Fertilizer was applied to half of the plants in each site. After seven months in the two given microenvironments, increased light and fertilization resulted in greater growth and some changes in the biomass allocation patterns. All measured variables responded similarly to reported changes for tree seedlings and saplings from other tropical and subtropical regions. Total growth parameters (height, biomass and leaf area) were very sensitive to increases in the main resource (light). The addition of nutrients was less important in producing changes in the allocation variables (root to shoot ratio, leaf area ratio, and specific leaf mass) under conditions of high light availability. Changes due to nutrient levels were relatively greater on plants grown under understory conditions. Also, small light differences among sites can cause significant changes in the variables related to total growth. Lastly, plant mortality in the nutrient treatments was found to be independent of mortality in two forest light environments. Some hypotheses about resource acquisition and plant growth are not supported by this data. C1 Univ Puerto Rico, Dept Biol, Rio Piedras, PR 00931 USA. RP Cordero, RAS (reprint author), Smithsonian Trop Res Inst, POB 2072, Balboa, Panama. RI Cordero Solorzano, Roberto A./H-8273-2016 OI Cordero Solorzano, Roberto A./0000-0001-7270-104X NR 26 TC 2 Z9 3 U1 1 U2 2 PU REVISTA DE BIOLOGIA TROPICAL PI SAN JOSE PA UNIVERSIDAD DE COSTA RICA CIUDAD UNIVERSITARIA, SAN JOSE, COSTA RICA SN 0034-7744 J9 REV BIOL TROP JI Rev. Biol. Trop. PD JUN-SEP PY 2000 VL 48 IS 2-3 BP 579 EP 586 PG 8 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 418CA UT WOS:000167871100029 PM 11354964 ER PT J AU Rivera, JHV Haas, CA Rappole, JH McShea, WJ AF Rivera, JHV Haas, CA Rappole, JH McShea, WJ TI Parental care of fledgling Wood Thrushes SO WILSON BULLETIN LA English DT Article ID MIXED REPRODUCTIVE STRATEGIES; BROOD DIVISION; ROBINS AB We report the study of parental care of Wood Thrush (Hylocichla mustelina) fledglings from nest-leaving to independence. From 1993 to 1995, we captured, radio-tagged, and monitored the movements and behavior of 23 fledglings and their parents from 12 broods at the U.S. Marine Corps Base, Quantico, Virginia. For pairs that subsequently renested (n = 5), the family group of male, female, and fledglings, remained within 62 (+/-5 SE) m of the first nest after fledging, During the period of post-fledging parental care, mean maximum distance between parents was 70 (+/-14) m. Females attended the young 13 (+/-1.3) days before initiating the incubation of a second clutch. Males continued attending the fledglings for 6 (+/-0.7) more days until the young achieved independence and dispersed (28-36 days post-hatching). In final clutches (n = 73, brood care was divided between the parents, and the position of the fledglings relative to the nest depended on the parents' choice of molting site tin the nesting area or elsewhere). Division of the brood by the parents has been thought to be a strategy to reduce predation and increase foraging efficiency. However, in the Wood Thrush and other species, joint attendance of initial broods, but division of final broods, suggest that other factors could be important for the parents' decision of whether or not to split the brood. C1 Virginia Polytech Inst & State Univ, Dept Fisheries & Wildlife Sci, Blacksburg, VA 24061 USA. Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Rivera, JHV (reprint author), Apartado Postal 21, San Patricio 48980, Jalisco, Mexico. RI Haas, Carola/B-5056-2009 OI Haas, Carola/0000-0002-5490-6882 NR 19 TC 20 Z9 20 U1 0 U2 5 PU WILSON ORNITHOLOGICAL SOC PI ANN ARBOR PA MUSEUM OF ZOOLOGY UNIV MICHIGAN, ANN ARBOR, MI 48109 USA SN 0043-5643 J9 WILSON BULL JI Wilson Bull. PD JUN PY 2000 VL 112 IS 2 BP 233 EP 237 DI 10.1676/0043-5643(2000)112[0233:PCOFWT]2.0.CO;2 PG 5 WC Ornithology SC Zoology GA 325JF UT WOS:000087671900007 ER PT J AU Christian, DG Roberts, D AF Christian, DG Roberts, D TI First description of nest and nesting behavior of the Nightingale Wren SO WILSON BULLETIN LA English DT Article AB Nests and nesting behavior of the Nightingale Wren (Microcerculus marginatus) in Panama are described. Two nests were found at the ends of horizontal burrows in dirt banks, presumably excavated by other species. The nest chambers were lined with dead leaf fragments. Clutch sizes were two and three eggs. Incubation period was 19 or 20 days for one nest, and the nestling period was 16 or 17 days for the second nest. A comparison of nests in the Troglodytidae shows the nests of M. marginatus to be most similar to those of the genera Salpinctes. Catherpes, and Hylorchilus, all of which are secondary cavity nesters. If nest type is a phylogenetically conserved characteristic, then these four genera may be more closely related than is reflected in current classifications. C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Christian, DG (reprint author), Louisiana State Univ, Dept Sci Biol, 119 Foster Hall, Baton Rouge, LA 70803 USA. NR 15 TC 3 Z9 3 U1 1 U2 2 PU WILSON ORNITHOLOGICAL SOC PI ANN ARBOR PA MUSEUM OF ZOOLOGY UNIV MICHIGAN, ANN ARBOR, MI 48109 USA SN 0043-5643 J9 WILSON BULL JI Wilson Bull. PD JUN PY 2000 VL 112 IS 2 BP 284 EP 287 DI 10.1676/0043-5643(2000)112[0284:FDONAN]2.0.CO;2 PG 4 WC Ornithology SC Zoology GA 325JF UT WOS:000087671900020 ER PT J AU Gaimari, SD Irwin, ME AF Gaimari, SD Irwin, ME TI Phylogeny, classification, and biogeography of the cycloteline Therevinae (Insecta : Diptera : Therevidae) SO ZOOLOGICAL JOURNAL OF THE LINNEAN SOCIETY LA English DT Review DE Asiloidea; cladistics; systematics; morphology; Laurasia; Beringia ID DEPENDENT PERMUTATION TEST; HISTORICAL BIOGEOGRAPHY; CONFIDENCE-LIMITS; ANCESTRAL AREAS; T-PTP; PARSIMONY; SYSTEMATICS; OUTGROUPS; PATTERNS; RECONSTRUCTION AB Twenty-one members of the Laurasian group of Therevinae (Diptera: Therevidae) are compared using 65 adult morphological characters. Cladistic analysis using parsimony on the 17 ingroup and 4 outgroup taxa provides a well-supported hypothesis of relationships among taxa within the Cyclotelini, tribe nov. The Cyclotelini is a monophyletic assemblage of mostly New World genera, including Anolinga, gen. nov., Breviperna Irwin, Coleiana, gen. nov., Crebraseta, gen. nov., Cyclotelus Walker, Nesonana, gen.nov., and Ozadiceromyia Bigot. In addition, three Old World genera, Amnothereva Lyneborg, Bugulaverpa, gen. nov., and Puocyclotelus Nagatomi 8r Lyneborg, are included in the tribe. These ten genera are divided into two monophyletic genus-groups, the Breviperna-group and the Cyclotelus-group. Keys are provided for the genera of Cyclotelini. The tribe, the two informal genus-groups, and all genera are diagnose; five new genera and six new species are proposed. The biogeographical histories of the genera are discussed in terms of their cladistic relationships using methods of cladistic biogeography. Two major vicariant events account for the current distribution of the tribe. The first relates to the Beringian land bridge connecting western North America and eastern Asia. Second, New World cyclotelines were profoundly affected by the Early Eocene breakup of the archipelagic bridge between North and South America, and the distributions support the hypotheses favouring the continental origin of the Greater Antilles. (C) 2000 The Linnean Society of London. C1 Univ Illinois, Urbana, IL 61801 USA. Illinois Nat Hist Survey, Urbana, IL 61801 USA. RP Gaimari, SD (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Entomol, Washington, DC 20560 USA. NR 213 TC 20 Z9 21 U1 0 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0024-4082 J9 ZOOL J LINN SOC-LOND JI Zool. J. Linn. Soc. PD JUN PY 2000 VL 129 IS 2 BP 129 EP 240 DI 10.1111/j.1096-3642.2000.tb00012.x PG 112 WC Zoology SC Zoology GA 326TT UT WOS:000087753400001 ER PT J AU Fleischhauer, M Lukin, MD AF Fleischhauer, M Lukin, MD TI Dark-state polaritons in electromagnetically induced transparency SO PHYSICAL REVIEW LETTERS LA English DT Article ID COHERENT POPULATION TRANSFER; QUANTUM STATES; GROUP-VELOCITY; ATOMIC GAS; LIGHT; PULSES; ENTANGLEMENT; SPECTROSCOPY; ENSEMBLE; NOISE AB We identify form-stable coupled excitations of light and matter ("dark-state polaritons") associated with the propagation of quantum fields in electromagnetically induced transparency. The properties of dark-state polaritons such as the group velocity are determined by the mixing angle between light and matter components and can be controlled by an external coherent field as the pulse propagates. In particular, light pulses can be decelerated and "trapped" in which case their shape and quantum state are mapped onto metastable collective states of matter. Possible applications of this reversible coherent-control technique are discussed. C1 Univ Munich, Sekt Phys, D-80333 Munich, Germany. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Fleischhauer, M (reprint author), Univ Munich, Sekt Phys, Theresienstr 37, D-80333 Munich, Germany. RI Fleischhauer, Michael/G-6716-2011 NR 31 TC 1018 Z9 1065 U1 2 U2 87 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 29 PY 2000 VL 84 IS 22 BP 5094 EP 5097 DI 10.1103/PhysRevLett.84.5094 PG 4 WC Physics, Multidisciplinary SC Physics GA 318CL UT WOS:000087266300016 ER PT J AU Condit, R Ashton, PS Baker, P Bunyavejchewin, S Gunatilleke, S Gunatilleke, N Hubbell, SP Foster, RB Itoh, A LaFrankie, JV Lee, HS Losos, E Manokaran, N Sukumar, R Yamakura, T AF Condit, R Ashton, PS Baker, P Bunyavejchewin, S Gunatilleke, S Gunatilleke, N Hubbell, SP Foster, RB Itoh, A LaFrankie, JV Lee, HS Losos, E Manokaran, N Sukumar, R Yamakura, T TI Spatial patterns in the distribution of tropical tree species SO SCIENCE LA English DT Article ID RAIN-FOREST; DIVERSITY AB Fully mapped tree census plots of large area, 25 to 52 hectares, have now been completed at six different sites in tropical forests, including dry deciduous to wet evergreen forest on two continents. One of the main goals of these plots has been to evaluate spatial patterns in tropical tree populations. Here the degree of aggregation in the distribution of 1768 tree species is examined based on the average density of conspecific trees in circular neighborhoods around each tree. When all individuals larger than 1 centimeter in stem diameter were included, nearly every species was more aggregated than a random distribution. Considering only larger trees (greater than or equal to 10 centimeters in diameter), the pattern persisted, with most species being more aggregated than random. Rare species were more aggregated than common species. All six forests were very similar in all the particulars of these results. C1 Smithsonian Trop Res Inst, Ctr Trop Forest Sci, Unit 0948, APO, AA 34002 USA. Harvard Univ, Inst Int Dev, Ctr Trop Forest Sci, Cambridge, MA 02138 USA. Univ Washington, Coll Forest Resources, Silviculture Lab, Seattle, WA 98195 USA. Royal Thai Forest Dept, Bangkok 10900, Thailand. Univ Peradeniya, Dept Bot, Peradeniya, Sri Lanka. Univ Georgia, Ctr Trop Forest Sci, Athens, GA 30602 USA. Field Museum Nat Hist, Ctr Trop Forest Sci, Chicago, IL 60605 USA. Osaka City Univ, Osaka 5588585, Japan. Nanyang Technol Univ, Natl Inst Educ, Ctr Trop Forest Sci, Singapore 1025, Singapore. Sarawak Forest Dept, Kuching 93660, Sarawak, Malaysia. Forest Res Inst Malaysia, Kuala Lumpur 52109, Malaysia. Indian Inst Sci, Bangalore 560012, Karnataka, India. RP Condit, R (reprint author), Smithsonian Trop Res Inst, Ctr Trop Forest Sci, Unit 0948, APO, AA 34002 USA. EM ctfs@tivoli.si.edu RI Raman, Sukumar/C-9809-2013 NR 24 TC 525 Z9 716 U1 11 U2 172 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 26 PY 2000 VL 288 IS 5470 BP 1414 EP 1418 DI 10.1126/science.288.5470.1414 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 318EL UT WOS:000087270900048 PM 10827950 ER PT J AU Fleischhauer, M Yelin, SF Lukin, MD AF Fleischhauer, M Yelin, SF Lukin, MD TI How to trap photons? Storing single-photon quantum states in collective atomic excitations SO OPTICS COMMUNICATIONS LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; POPULATION-INVERSION; GROUP-VELOCITY; INTERFERENCE; COHERENCE; LIGHT; GAS; COMMUNICATION; ENHANCEMENT; RESONANCES AB We show that it is possible to 'store' quantum states of single-photon fields by mapping them onto collective meta-stable states of an optically dense, coherently driven medium inside an optical resonator. An adiabatic technique is suggested which allows to transfer non-classical. correlations from traveling-wave single-photon wave-packets into atomic states and vise versa with nearly 100% efficiency. In contrast to previous approaches involving single atoms, the present technique does not require the strong coupling regime corresponding to high-Q micro-cavities. Instead, intracavity electromagnetically Induced Transparency is used to achieve a strong coupling between the cavity mode and the atoms. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Harvard Smithsonian Ctr Astrophys, ITAMP, Cambridge, MA 02138 USA. Univ Munich, Sekt Phys, D-80333 Munich, Germany. MIT, Elect Res Lab, Cambridge, MA 02143 USA. RP Harvard Smithsonian Ctr Astrophys, ITAMP, Cambridge, MA 02138 USA. EM mfleisch@theorie.physik.uni-muenchen.de RI Fleischhauer, Michael/G-6716-2011 NR 40 TC 127 Z9 128 U1 1 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 EI 1873-0310 J9 OPT COMMUN JI Opt. Commun. PD MAY 25 PY 2000 VL 179 IS 1-6 BP 395 EP 410 DI 10.1016/S0030-4018(99)00679-3 PG 16 WC Optics SC Optics GA 326NP UT WOS:000087741900041 ER PT J AU Fry, ES Lukin, MD Walther, T Welch, GR AF Fry, ES Lukin, MD Walther, T Welch, GR TI Four-level atomic coherence and cw VUV lasers SO OPTICS COMMUNICATIONS LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; POPULATION-INVERSION; QUANTUM INTERFERENCE; AMPLIFICATION; OSCILLATION; RESONANCES AB We demonstrate the feasibility of utilizing the so-called 'double-dark' scheme of four-level atomic coherence to obtain strong laser gain in the ultra-violet and vacuum ultra-violet. Furthermore, we show a new technique for eliminating Doppler broadening in a large class of multi-level (greater than or equal to 4) schemes. A specific application of these ideas to cw lasing at 253 nm and 185 nm in Hg is presented. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Harvard Smithsonian Ctr Astrophys, ITAMP, Cambridge, MA 02138 USA. RP Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. EM thw@tamu.edu RI Fry, Edward/B-6012-2016; Walther, Thomas/C-6212-2016 OI Walther, Thomas/0000-0001-8114-1785 NR 20 TC 31 Z9 31 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 EI 1873-0310 J9 OPT COMMUN JI Opt. Commun. PD MAY 25 PY 2000 VL 179 IS 1-6 BP 499 EP 504 DI 10.1016/S0030-4018(99)00731-2 PG 6 WC Optics SC Optics GA 326NP UT WOS:000087741900053 ER PT J AU Vardi, A AF Vardi, A TI On the role of intermolecular interactions in establishing chiral stability SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CONSERVING ENERGY DIFFERENCE; BOSE-EINSTEIN CONDENSATE; MIRROR-IMAGE MOLECULES; WEAK-INTERACTIONS; OPTICAL-ACTIVITY; SYMMETRY-BREAKING; TIME-DEPENDENCE; PARITY; ENANTIOMERS; MIXTURES AB I study the effect of intermolecular interactions on coherent tunneling racemization within the framework of the Hund double well model. Two self-consistent equations for the well population amplitudes, coupled by a tunneling matrix element, are used to describe the system dynamics. It is shown that the equations of motion are nonlinear due to the difference between homochiral interactions and heterochiral interactions. The consequence of this nonlinearity is that chiral molecular configurations are far more stable than expected by the Hund model for isolated molecules. Moreover, when the homochiral interactions are energetically favorable to heterochiral interactions (weaker homochiral repulsive interactions or stronger homochiral attractive interactions), spontaneous symmetry breaking may amplify the optical activity of a nearly racemic mixture. (C) 2000 American Institute of Physics. [S0021-9606(00)02220-0]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Vardi, A (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RI Vardi, Amichay/D-8189-2011 OI Vardi, Amichay/0000-0002-8992-2129 NR 38 TC 17 Z9 17 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 22 PY 2000 VL 112 IS 20 BP 8743 EP 8746 AR PII [S0021-9606(00)02220-0] DI 10.1063/1.481489 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 310WC UT WOS:000086851200001 ER PT J AU Menou, K Hameury, JM Lasota, JP Narayan, R AF Menou, K Hameury, JM Lasota, JP Narayan, R TI Disc instability models for X-ray transients: evidence for evaporation and low alpha-viscosity? SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; black hole physics; MHD; turbulence; novae, cataclysmic variables; X-rays : stars ID DWARF-NOVA OUTBURSTS; ADVECTION-DOMINATED ACCRETION; LONG-TERM BEHAVIOR; BLACK-HOLES; COOLING FRONTS; SS-CYGNI; UV DELAY; WZ-SGE; QUIESCENCE; BINARIES AB We construct time-dependent models of accretion discs around black holes and neutron stars. We investigate the effect that evaporation of the inner disc regions during quiescence has upon the predictions of the disc instability model (DIM) for these systems. We do not include irradiation of the disc in the models. Removing the inner, most unstable, parts of the accretion disc increases the predicted recurrence times. However, DIMs with values of the viscosity parameter alpha(hot)similar to 0.1 and alpha(cold)similar to 0.02 (values typically used in applications of the DIM to standard dwarf nova outbursts) fail to reproduce the long recurrence times of soft X-ray transients (unless we resort to fine-tuning the parameters), independent of the evaporation strength. We show that models in which evaporation is included and a smaller value of alpha(cold) (similar to 0.005) used do reproduce the long recurrence times and the accretion rates at the level of the Eddington rate observed in outburst. The large difference between the values of alpha(hot) and alpha(cold), if confirmed once disc irradiation is included, suggests that several viscosity mechanisms operate in these accretion discs. For some parameter sets our models predict re-flares during the decline from outburst. The re-flares are a physical property of the model and result from the formation of a heating front in the wake of an initial cooling front, and subsequent multiple front reflections. The re-flares disappear in low-alpha models where front reflection cannot occur. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Observ Paris, Sect Meudon, Dept Astrophys Relativiste & Cosmol, CNRS,UMR 8629, F-92195 Meudon, France. Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA. Observ Strasbourg, CNRS, UMR 7550, F-67000 Strasbourg, France. Inst Astrophys, F-75014 Paris, France. RP Menou, K (reprint author), Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. OI Narayan, Ramesh/0000-0002-1919-2730 NR 71 TC 35 Z9 35 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 21 PY 2000 VL 314 IS 3 BP 498 EP 510 DI 10.1046/j.1365-8711.2000.03357.x PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 317DA UT WOS:000087210000007 ER PT J AU Magliocchetti, M Bagla, JS Maddox, SJ Lahav, O AF Magliocchetti, M Bagla, JS Maddox, SJ Lahav, O TI The observed evolution of galaxy clustering versus epoch-dependent biasing models SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : clusters : general; galaxies : general; cosmology : theory; large-scale structure of Universe ID HUBBLE-DEEP-FIELD; REDSHIFT SURVEY; COSMOLOGICAL CONSTANT; SPECTRUM AB We study the observed evolution of galaxy clustering as a function of redshift. We find that the clustering of galaxies, parametrized by the amplitude of fluctuations in the distribution of galaxies at a comoving scale of 8 h(-1) Mpc, decreases as we go from observations of the local Universe to z similar to 2. On the other hand, clustering of the Lyman-break galaxies at z similar to 3 is very strong, comparable to the clustering of present-day galaxies. However, there are three major factors to take into account while comparing clustering measurements coming from various surveys: the so-called 'scale-dependence' effect, caused by measurements being made at different scales; the 'type-selection' effect introduced by the fact that different galaxy surveys select different populations, which do not have the same clustering amplitudes; and the Malmquist bias, which means that within a given survey the more distant galaxies tend to have brighter absolute magnitudes, and so do not have the same clustering amplitude. We correct for the first two effects and discuss the implications of Malmquist bias on the interpretation of the data at different z. We then compare the observed galaxy clustering with models for the evolution of clustering in some fixed cosmologies. Correcting for the scale-dependence effect significantly reduces the discrepancies between different measurements. We interpret the observed clustering signal at high redshift as coming from objects that are highly biased with respect to the underlying distribution of mass; this is not the case for z less than or similar to 2, where measurements are compatible with the assumption of a much lower biasing level, which only shows a weak dependence on z. Present observations still do not provide a strong constraint because of the large uncertainties, but clear distinctions will be possible when larger data sets from surveys in progress become available. Finally we propose a model-independent test that can be used to place a lower limit on the density parameter Omega(0). C1 Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Nottingham, Sch Phys & Astron, Nottingham NG7 2RD, England. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. SISSA, I-34014 Trieste, Italy. Mehta Res Inst, Allahabad 211019, Uttar Pradesh, India. RP Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England. EM manuela@ast.cam.ac.uk OI Maddox, Stephen/0000-0001-5549-195X; Magliocchetti, Manuela/0000-0001-9158-4838 NR 48 TC 38 Z9 38 U1 0 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 EI 1365-2966 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 21 PY 2000 VL 314 IS 3 BP 546 EP 556 DI 10.1046/j.1365-8711.2000.03314.x PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 317DA UT WOS:000087210000009 ER PT J AU Pomarede, D Badran, HM Behr, L Boyle, PJ Brunetti, MT Fegan, DJ Harris, K Horan, D Plouin, F Urban, M Weekes, TC AF Pomarede, D Badran, HM Behr, L Boyle, PJ Brunetti, MT Fegan, DJ Harris, K Horan, D Plouin, F Urban, M Weekes, TC TI A new optical filter for the ARTEMIS experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID CHARGE RATIO; GAMMA-RAY; MOON; SPECTRUM; MUONS; TEV; SHOWERS AB The properties of a new liquid filter for the ARTEMIS experiment are reported. ARTEMIS, which is run at the Whipple Gamma-Ray/Cosmic-Ray Telescope, aims to measure the negatively charged component of hadronic cosmic rays (presumably antiprotons) in the 1 TeV region. The Earth-Moon system is used as a spectrometer to perform a magnetic analysis of cosmic rays passing close to the Moon. The Moon acts as an aperture stop, resulting in a deficit of both protons and antiprotons. Air showers are detected using Cherenkov light emitted in the ultraviolet (UV) range in order to benefit from the large moonlight absorption through ozone in the upper atmosphere. The liquid UV filter needed to complement the ozone effect has been added to with a recently discovered dye. We report here on observations made using this dye. A background reduction to only 3% of its value without the dye has been achieved while maintaining the signal amplitude to at least 75% of its level. The reduced sensitivity to moonlight permits a lowering of the trigger threshold which, in turn, increases the air shower registration efficiency by a factor of three. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Ecole Polytech, LPNHE, F-91128 Palaiseau, France. Tanta Univ, Fac Sci, Dept Phys, Tanta, Egypt. Univ Coll Dublin, Dept Phys, Dublin 4, Ireland. Univ Perugia, Dipartimento Fis, I-06100 Perugia, Italy. Harvard Smithsonian Ctr Astrophys, Whipple Observ, Amado, AZ 85645 USA. RP Plouin, F (reprint author), Ecole Polytech, LPNHE, F-91128 Palaiseau, France. OI Pomarede, Daniel/0000-0003-2038-0488 NR 62 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 21 PY 2000 VL 446 IS 3 BP 469 EP 489 DI 10.1016/S0168-9002(99)01185-7 PG 21 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 318YP UT WOS:000087312500006 ER PT J AU Bragg, AE Greenhill, LJ Moran, JM Henkel, C AF Bragg, AE Greenhill, LJ Moran, JM Henkel, C TI Accelerations of water masers in NGC 4258 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (NGC 4258); galaxies : kinematics and dynamics galaxies : nuclei; masers ID ACTIVE GALACTIC NUCLEI; H2O MASER; ASTROPHYSICAL MASERS; GALAXY NGC4258; BLACK-HOLE; NGC-4258; EMISSION; DISK; ALTERNATIVES; NGC-3079 AB The water masers in NGC 4258 delineate the structure and dynamics of a subparsec-diameter accretion disk around a supermassive black hole. Very Long Baseline Array (VLBA) observations provide precise information about the positions in the plane of the sky and the three-dimensional velocity vectors for the maser emission, but the positions along the line of sight must be inferred from models. Previous measurements placed an upper limit on the accelerations of the high-velocity spectral features of 1 km s(-1) yr(-1), suggesting that they are located near the midline (the diameter perpendicular to the line of sight), where they would have exactly zero acceleration. From similar measurements, the accelerations of the systemic velocity spectral features have been estimated to be about 9 km s(-1) yr(-1), indicating that they lie toward the front of the disk where the acceleration vector points directly away from the line of sight. We report acceleration measurements for 12 systemic velocity spectral features and 19 high-velocity spectral features using a total of 25 epochs of observations from Effelsberg (five epochs), the Very Large Array (15 epochs), and the VLBA (five epochs) spanning the years 1994-1997. The measured accelerations of the systemic velocity features are between 7.5 and 10.4 km s(-1) yr(-1), and there is no evidence for a dip in the spectrum at the systemic velocity. Such a dip has been attributed in the past to an absorbing layer of noninverted H2O. The accelerations of the high-velocity features, measured here for the first time, range from -0.77 to 0.38 km s(-1) yr-'. From the line-of-sight accelerations and velocities, we infer the positions of these high-velocity masers with a simple edge-on disk model The resulting positions fall. between -13 degrees 6 and 9 degrees 3 in azimuth (measured from the midline). A model that suggests a spiral shock origin of the masers, in which changes in maser velocity are due to the outward motion of the shock wave, predicts apparent accelerations of -0.05(theta(p)/2 degrees 5) km s(-1) yr(-1), where theta(p) is the pitch angle of the spiral arms. Our data are not consistent with these predictions. We also discuss the physical properties of the high-velocity masers. Most notably, the strongest high-velocity masers lie near the midline, where the velocity gradient is smallest, thereby providing the longest amplification path lengths. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Max Planck Inst Radioastron, D-53121 Bonn, Germany. RP Bragg, AE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 30 TC 25 Z9 27 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2000 VL 535 IS 1 BP 73 EP 89 DI 10.1086/308829 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325DW UT WOS:000087661900008 ER PT J AU Magnani, L Hartmann, D Holcomb, SL Smith, LE Thaddeus, P AF Magnani, L Hartmann, D Holcomb, SL Smith, LE Thaddeus, P TI A survey of high-latitude molecular gas in the southern Galactic hemisphere SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; ISM : molecules; radio lines : ISM ID WAVE CONTINUUM SOURCES; SURFACE MASS DENSITY; CO SURVEY; CLOUDS; DISK; TRANSLUCENT; QUADRANT; EMISSION; CIRRUS AB To determine the distribution of molecular gas at high Galactic latitudes, nearly one-half of the southern Galactic hemisphere at b less than or equal to -30 degrees was surveyed in the CO (1-0) transition at 115 GHz. The sampling was done on a locally Cartesian grid with 1 degrees (true angle) spacing in Galactic longitude and latitude. Of the 11,478 points in the grid, the 4982 that rise above an elevation of 30 degrees in Cambridge, Massachusetts, the site of the 1.2 m millimeter-wave telescope used for the survey, were observed to an rms of T-A* similar to 0.1 K. We found 144 distinct CO (1-0) emission lines along 133 lines of sight. Of these detections, 58 are new and 75 are associated with 26 previously cataloged high-latitude molecular clouds situated within the survey boundaries. The surface filling factor of molecular gas is 0.03, a factor of 10 greater than that found in the northern Galactic hemisphere at b greater than or equal to +30 degrees. On the assumption that the CO/H-2 ratio [N(H-2)/W(CO)] is given by 1.0 x 10(20) cm(-2) (K km s(-1))(-1), the mass surface density of molecular gas in the region of the survey is 0.09 M. pc(-2). The Gaussian scale height of the 133 detections is similar to 100 pc, consistent with that determined for lower latitude dark clouds. C1 Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Max Planck Inst Radioastron, D-53121 Bonn, Germany. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Magnani, L (reprint author), Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. NR 29 TC 39 Z9 39 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2000 VL 535 IS 1 BP 167 EP 175 DI 10.1086/308841 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325DW UT WOS:000087661900015 ER PT J AU Ingalls, JG Bania, TM Lane, AP Rumitz, M Stark, AA AF Ingalls, JG Bania, TM Lane, AP Rumitz, M Stark, AA TI Physical state of molecular gas in high galactic latitude translucent clouds SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; ISM : molecules; submillimeter ID SMALL-SCALE STRUCTURE; IRAM KEY-PROJECT; T-TAURI STARS; INTERSTELLAR-MEDIUM; VELOCITY STRUCTURE; FORMING REGIONS; CIRRUS CLOUDS; ATOMIC CARBON; CO; EMISSION AB The rotational transitions of carbon monoxide (CO) are the primary means of investigating the density and velocity structure of the molecular interstellar medium. Here we study the lowest four rotational transitions of CO toward high-latitude translucent molecular clouds (HLCs). We report new observations of the J = (4-3), (2-1), and (1-0) transitions of CO toward eight high-latitude clouds. The new observations are combined with data from the literature to show that the emission from all observed CO transitions is linearly correlated. This implies that the excitation conditions that lead to emission in these transitions are uniform throughout the clouds. Observed (CO)-C-13/(CO)-C-12 (1_0) integrated intensity ratios are generally much greater than the expected abundance ratio of the two species, indicating that the regions that emit (CO)-C-12 (1-0) radiation are optically thick. We develop a statistical method to compare the observed line ratios with models of CO excitation and radiative transfer. This enables us to determine the most likely portion of the physical parameter space that is compatible with the observations. The model enables us to rule out CO gas temperatures greater than similar to 30 K, since the most likely high-temperature configurations are 1 pc-sized structures aligned along the line of sight. The most probable solution is a high-density and low-temperature (HDLT) solution, with volume density, n=10(4.5+/-0.5) cm(-3), kinetic temperature, T-k approximate to 8 K, and CO column density per velocity interval N-CO/Delta V. = 10(16.6+/-0.3) cm(-2)/(km s(-1)). The CO cell size is L similar to 0.01 pc (similar to 2000 AU). These cells are thus tiny fragments within the similar to 100 times larger GO-emitting extent of a typical high-latitude cloud. We discuss the physical implications of HDLT cells, and we suggest ways to test for their existence. C1 Boston Univ, Dept Astron, Boston, MA 02215 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ingalls, JG (reprint author), CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, 770 W Wilson Ave, Pasadena, CA 91125 USA. RI Bania, Thomas/H-2318-2014 NR 55 TC 15 Z9 15 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2000 VL 535 IS 1 BP 211 EP 226 DI 10.1086/308831 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325DW UT WOS:000087661900018 ER PT J AU Wood, BE Karovska, M AF Wood, BE Karovska, M TI Studying the pulsation of Mira variables in the ultraviolet SO ASTROPHYSICAL JOURNAL LA English DT Article DE line : profiles; stars : AGB and post-AGB; stars : oscillations; stars : variables : other; ultraviolet : stars ID LONG-PERIOD VARIABLES; II EMISSION-LINES; LATE-TYPE STARS; INFRARED VELOCITIES; COOL; MECHANISMS; PROFILES; SPECTRA; GIANTS; GHRS AB Ne present results from an empirical study of the Mg II h and k emission lines of selected Mira variable stars, using spectra from the International Ultraviolet Explorer (IUE). The stars all exhibit similar Mg II behavior during the course of their pulsation cycles. The Mg II flux always peaks after optical maximum near pulsation phase phi = 0.2-0.5, although the Mg II flux can vary greatly from one cycle to the next. The lines are highly blueshifted, with the magnitude of the blueshift decreasing with phase. The widths of the Mg II lines are also phase dependent, decreasing from about 70 km s(-1) to 40 km s(-1) between phi = 0.2 and phi = 0.6. We also study other UV emission lines apparent in the IUE spectra, most of them Fe II lines. These lines are much narrower and not nearly as blueshifted as the Mg II lines. They exhibit the same phase-dependent flux behavior as Mg II, but they do not show similar velocity or width variations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Wood, BE (reprint author), Univ Colorado, JILA, Boulder, CO 80309 USA. EM wood@head-cfa.harvard.edu; karovska@head-cfa.harvard.edu NR 35 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2000 VL 535 IS 1 BP 304 EP 315 DI 10.1086/308838 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325DW UT WOS:000087661900027 ER PT J AU Reale, F Peres, G Serio, S DeLuca, EE Golub, L AF Reale, F Peres, G Serio, S DeLuca, EE Golub, L TI A brightening coronal loop observed by TRACE. I. Morphology and evolution SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : activity; Sun : corona; Sun : X-rays, gamma rays ID TRANSITION REGION; SOLAR; DIAGNOSTICS; PLASMA; FLARE; NIXT AB We analyze the transient brightening of a solar coronal loop observed, at high time cadence (30 s) and spatial resolution (0."5 pixel size), with the Transition Region and Coronal Explorer (TRACE) in the 171 A band on 1998 June 26. The loop, located in AR 8253, is approximate to 10(10) cm long and inclined with respect to the vertical to the solar surface. Its geometry and shape do not change significantly during the brightening, which lasts for similar to 2 hr and is preceded by highly dynamic events in nearby and perhaps interacting loops. The loop footpoints brighten first; after similar to 10 minutes, moving brightness fronts rise initially from the northern footpoint, and after another similar to 7 minutes from the southern one, at an apparent speed similar to 100 km s(-1), the whole loop becoming clearly visible afterward. During the rising phase the loop evolves coherently as a single magnetic tube. The brightness profile is asymmetric with respect to the loop apex at all times; the brightness contrast between the footpoints and the apex decreases with time from a ratio of similar to 10 to similar to 3. After the loop has become all visible, the several parallel filaments which form it follow an independent evolution. Assuming a plasma temperature of approximate to 1 MK, we infer a plasma density of similar to 6 x 10(8) cm(-3) and a pressure of similar to 0.2 dyn cm(-2) close to the loop apex at the luminosity maximum. A companion paper is devoted to modeling the rising phase of this event. C1 Univ Palermo, Dipartimento Sci Fis & Astron, Sez Astron, I-90134 Palermo, Italy. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Osservat Astron, I-90134 Palermo, Italy. RP Univ Palermo, Dipartimento Sci Fis & Astron, Sez Astron, Piazza Parlamento 1, I-90134 Palermo, Italy. RI DeLuca, Edward/L-7534-2013; OI DeLuca, Edward/0000-0001-7416-2895; Reale, Fabio/0000-0002-1820-4824; Golub, Leon/0000-0001-9638-3082 NR 13 TC 27 Z9 28 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 MAY 20 PY 2000 VL 535 IS 1 BP 412 EP 422 DI 10.1086/308816 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325DW UT WOS:000087661900038 ER PT J AU Reale, F Peres, G Serio, S Betta, RM DeLuca, EE Golub, L AF Reale, F Peres, G Serio, S Betta, RM DeLuca, EE Golub, L TI A brightening coronal loop observed by TRACE. II. Loop modeling and constraints on heating SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : activity; Sun : corona; Sun : X-rays, gamma rays ID X-RAY; SIPHON FLOWS; HYDRODYNAMIC MODEL; TRANSITION REGION; IMPULSIVE PHASE; SOLAR-FLARES; SPECTROSCOPY; GASDYNAMICS; DYNAMICS AB This is the second of two papers dedicated to the brightening of a coronal loop observed by the Transition Region and Coronal Explorer (TRACE) on 1998 June 26; it aims at hydrodynamic modeling of the brightening. Since the loop geometry is practically unchanged during the brightening, the evolution of the plasma cofined in the loop is described with a one-dimensional hydrodynamic time-dependent numerical model, and from the results the emission along the loop in the TRACE 171 Angstrom band is synthesized. The information from Paper I is used to derive the geometry and the initial configuration of the loop as well as for comparison with the results of the model. The modeling is focused to determine the amount, spatial distribution, and evolution of the heating deposited in the loop to make the modeled evolution close to that observed with TRACE. We find that, in order to match the observed evolution and distribution of the brightness along the loop, the heating has to be nonsymmetrical in the loop, in particular, deposited between the apex and one footpoint (3 x 10(9) cm from the southern footpoint). A reasonable match with observations is obtained by assuming that the heating is switched on abruptly and then kept constant for the whole rising phase. An even better match is obtained with the heating high and constant for 100 s and then decaying exponentially with an e-folding time of 300 s. We discuss the resulting physical scenario; a bright irregular structure close to the loop in the TRACE images may be a tracer of the heating release. C1 Univ Palermo, Sez Astron, Dipartimento Sci Fis & Astron, I-90134 Palermo, Italy. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Osservat Astron, I-90134 Palermo, Italy. RP Univ Palermo, Sez Astron, Dipartimento Sci Fis & Astron, Piazza Parlamento 1, I-90134 Palermo, Italy. RI DeLuca, Edward/L-7534-2013; OI DeLuca, Edward/0000-0001-7416-2895; Reale, Fabio/0000-0002-1820-4824; Golub, Leon/0000-0001-9638-3082 NR 32 TC 45 Z9 46 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 MAY 20 PY 2000 VL 535 IS 1 BP 423 EP 437 DI 10.1086/308817 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325DW UT WOS:000087661900039 ER PT J AU Hasan, SS Kalkofen, W van Ballegooijen, AA AF Hasan, SS Kalkofen, W van Ballegooijen, AA TI Excitation of oscillations in the magnetic network on the Sun SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; Sun : magnetic fields; Sun : oscillations ID PHOTOSPHERIC FLUX TUBES; SOLAR GRANULATION; BRIGHT POINTS; DYNAMICS; ELEMENTS; CHROMOSPHERE; ATMOSPHERE; MOTION; WAVES AB We examine the excitation of oscillations in the magnetic network of the Sun through the footpoint motion of photospheric magnetic flux tubes located in intergranular lanes. The motion is derived from a time series of high-resolution G-band and continuum filtergrams using an object-tracking technique. We model the response of the flux tube to the footpoint motion in terms of the Klein-Gordon equation, which is solved analytically as an initial value problem for transverse (kink) waves. We compute the wave energy flux in upward-propagating transverse waves. In general we find that the injection of energy into the chromosphere occurs in short-duration pulses, which would lead to a time variability in chromospheric emission that is incompatible with observations. Therefore, we consider the effects of turbulent convective flows on flux tubes in intergranular lanes. The turbulent flows are simulated by adding high-frequency motions (periods 5-50 s) with an amplitude of 1 km s(-1). The latter are simulated by adding random velocity fluctuations to the observationally determined velocities. In this case, we find that the energy flux is much less intermittent and can in principle carry adequate energy for chromospheric heating. C1 Indian Inst Astrophys, Bangalore 560034, Karnataka, India. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hasan, SS (reprint author), Indian Inst Astrophys, Bangalore 560034, Karnataka, India. RI Hasan, Siraj/C-2927-2012 NR 19 TC 29 Z9 29 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2000 VL 535 IS 1 BP L67 EP L70 DI 10.1086/312688 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325EA UT WOS:000087662300017 ER PT J AU Muzerolle, J Calvet, N Briceno, C Hartmann, L Hillenbrand, L AF Muzerolle, J Calvet, N Briceno, C Hartmann, L Hillenbrand, L TI Disk accretion in the 10 Myr old T Tauri stars TW Hydrae and Hen 3-600A SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; stars : formation; stars : individual (TW Hydrae); stars : pre-main-sequence; techniques : spectroscopic ID MAIN-SEQUENCE STARS; MAGNETOSPHERIC ACCRETION; EMISSION AB We have found that two members of the TW Hydrae association, TW Hydrae and Hen 3-600A, are still actively accreting, based on the ballistic infall signature of their broad H alpha emission profiles. We present the first quantitative analysis of accretion in these objects and conclude that the same accretion mechanisms which operate in the well-studied 1 Myr old T Tauri stars can and do occur in older (10 Myr) stars. We derive the first estimates of the disk mass accretion rate in TW Hya and Hen 3-600A, which are 1-2 orders of magnitude lower than the average rates in 1 Myr old objects. The decrease in accretion rates over 10 Myr, as well as the low fraction of TW Hya association objects still accreting, points to significant disk evolution, possibly linked to planet formation. Given the multiplicity of the Hen 3-600 system and the large UV excess of TW Hya, our results show that accretion disks can be surprisingly long lived in spite of the presence of companions and significant UV ionizing flux. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Massachusetts, Coll 5, Dept Astron, Amherst, MA 01003 USA. Ctr Invest Astron, Merida, Venezuela. Yale Univ, Dept Phys, New Haven, CT 06520 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. RP Muzerolle, J (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 42, Cambridge, MA 02138 USA. NR 29 TC 180 Z9 180 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2000 VL 535 IS 1 BP L47 EP L50 DI 10.1086/312691 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325EA UT WOS:000087662300012 ER PT J AU Warren, HP Winebarger, AR AF Warren, HP Winebarger, AR TI Small scale structure in the solar transition region SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona; Sun : transition region ID UNRESOLVED FINE-STRUCTURES; TEMPERATURE REGION; SUMER TELESCOPE; ATMOSPHERE; CORONA; SOHO; SPECTROMETER; NETWORK; PLASMAS; SPECTRA AB We present analysis of a high spatial resolution (similar to 1." 5) O VI lambda 1032 spectroheliogram taken with the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer on the Solar and Heliospheric Observatory. This image shows numerous narrow, looplike structures. The widths of the narrowest resolved features are at the spatial resolution of the SUMER spectrometer. In contrast to earlier Skylab observations, however, comparisons with a Michelson Doppler Imager magnetogram reveals that the majority of these looplike structures do not connect: network magnetic fields. Instead, they extend from the supergranulation network into the cell-center regions where no magnetic fields are detected in these data. We conjecture that these fine structures are related to spicules and are highly dynamic. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Warren, HP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 58, Cambridge, MA 02138 USA. NR 27 TC 21 Z9 21 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2000 VL 535 IS 1 BP L63 EP L66 DI 10.1086/312690 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325EA UT WOS:000087662300016 ER PT J AU Roper, C AF Roper, C TI Opinion interview SO NEW SCIENTIST LA English DT Editorial Material C1 Smithsonian Inst, Dept Invertebrate Biol, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NEW SCIENTIST PUBL EXPEDITING INC PI ELMONT PA 200 MEACHAM AVE, ELMONT, NY 11003 USA SN 0262-4079 J9 NEW SCI JI New Sci. PD MAY 20 PY 2000 VL 166 IS 2239 BP 40 EP 43 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 316GX UT WOS:000087160200023 ER PT J AU Webster, CR Michelsen, HA Gunson, MR Margitan, JJ Russell, JM Toon, GC Traub, WA AF Webster, CR Michelsen, HA Gunson, MR Margitan, JJ Russell, JM Toon, GC Traub, WA TI Response of lower stratospheric HCl/Cl-y to volcanic aerosol: Observations from aircraft, balloon, space shuttle, and satellite instruments SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SULFURIC-ACID; OZONE DEPLETION; MT-PINATUBO; ARCTIC STRATOSPHERE; BORNE MEASUREMENTS; ATMOS MEASUREMENTS; SULFATE AEROSOLS; ER-2 AIRCRAFT; CHLORINE; CLO AB Vertical profiles of HCl/Cl-y measured by space shuttle (Atmospheric Trace Molecule Spectroscopy (ATMOS)) and balloon (MkIV) instruments from 1985 through 1994 show that the increased volcanic aerosol from Mount Pinatubo had little effect on chlorine partitioning above 21 km. Below 21 km, however, large changes in HCl/l(y) were observed. Aircraft (Aircraft Laser Infrared Absorption Spectrometer), balloon (MkIV, Far Infrared Spectrometer 2), space shuttle (ATMOS), and satellite (Halogen Occultation Experiment) measurements below 21 km reveal an increase in HCl/Cl-y between early 1993 and late 1997 of 31 +/- 9%. This growth rate is 2 to 3 times larger than model estimates of the effect of the change in aerosol surface area and volume over this time period. For 1993 the five independent direct measurements of HCl/Cl-y produce a mean value of 0.57 +/- 0.05, whereas by 1997 the mean value was 0.75 +/- 0.07, in excellent agreement with the pre-Pinatubo mean of 0.74 +/- 0.11. Measurements made in 1992 at the peak of the post-Pinatubo midlatitude aerosol loading demonstrate large variability, which is qualitatively consistent with model predictions. This variability appears to be attributable to the temperature sensitivity of the Cl-y partitioning when aerosol abundances are high. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Hampton Univ, Dept Phys, Hampton, VA 23668 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Webster, CR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM cwebster@alpha1.jpl.nasa.gov NR 56 TC 6 Z9 6 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 16 PY 2000 VL 105 IS D9 BP 11711 EP 11719 DI 10.1029/1999JD901135 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 315RA UT WOS:000087125700015 ER PT J AU Froelich, P Jonsell, S Saenz, A Zygelman, B Dalgarno, A AF Froelich, P Jonsell, S Saenz, A Zygelman, B Dalgarno, A TI Hydrogen-antihydrogen collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID ANNIHILATION; ANTIPROTON AB Matter-antimatter interactions are investigated using hydrogen-antihydrogen collisions as an example. Cross sections for elastic scattering and for the antihydrogen loss (either through the rearrangement reaction, resulting in formation of protonium and positronium according to H + (H) over bar --> p (p) over bar + e(+)e(-), or via annihilation in flight) are calculated for the first time in a fully quantum mechanical approach. Implications for experiments intending to trap and cool antihydrogen are discussed. C1 Uppsala Univ, Dept Quantum Chem, S-75120 Uppsala, Sweden. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Froelich, P (reprint author), Uppsala Univ, Dept Quantum Chem, S-75120 Uppsala, Sweden. RI Jonsell, Svante/J-2251-2016 OI Jonsell, Svante/0000-0003-4969-1714 NR 9 TC 62 Z9 62 U1 0 U2 4 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 15 PY 2000 VL 84 IS 20 BP 4577 EP 4580 DI 10.1103/PhysRevLett.84.4577 PG 4 WC Physics, Multidisciplinary SC Physics GA 313JT UT WOS:000086997100016 ER PT J AU Loeb, A Waxman, E AF Loeb, A Waxman, E TI Cosmic gamma-ray background from structure formation in the intergalactic medium SO NATURE LA English DT Article ID COMA-CLUSTER; HIGH-ENERGY; LUMINOSITY FUNCTION; ACCELERATION; DISCOVERY; SPECTRUM; EMISSION; ORIGIN; ABSORPTION; GALAXIES AB The Universe is filled with a diffuse background of gamma-ray radiation(1), the origin of which remains one of the unsolved puzzles of cosmology. Less than one-quarter of the gamma-ray flux can be attributed to unresolved discrete sources(2,3), such as active galactic nuclei; the remainder appears to constitute a truly diffuse background. Here we show that the shock waves induced by gravity in the gas of the intergalactic medium, during the formation of large-scale structures like filaments and sheets of galaxies, produce a population of highly relativistic electrons. These electrons scatter a small fraction of the cosmic microwave background photons in the local Universe up to gamma-ray energies, thereby providing the gamma-ray background. The predicted diffuse flux agrees with the observed background across more than four orders of magnitude in photon energy, and the model predicts that the gamma-ray background, though generated locally, is isotropic to better than five per cent on angular scales larger than a degree. Moreover, the agreement between the predicted and observed background fluxes implies a mean cosmological density of baryons that is consistent with Big Bang nucleosynthesis. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Weizmann Inst Sci, Dept Condensed Matter Phys, IL-76100 Rehovot, Israel. RP Loeb, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI WAXMAN, ELI/K-1557-2012 NR 35 TC 151 Z9 151 U1 0 U2 4 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAY 11 PY 2000 VL 405 IS 6783 BP 156 EP 158 DI 10.1038/35012018 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 314WG UT WOS:000087080100041 ER PT J AU Iwamoto, K Nakamura, T Nomoto, K Mazzali, PA Danziger, IJ Garnavich, P Kirshner, R Jha, S Balam, D Thorstensen, J AF Iwamoto, K Nakamura, T Nomoto, K Mazzali, PA Danziger, IJ Garnavich, P Kirshner, R Jha, S Balam, D Thorstensen, J TI The peculiar type Ic supernova 1997ef: Another hypernova SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (UGC 4107); radiative transfer; supernovae : individual (SN 1997ef) ID GAMMA-RAY BURST; 25 APRIL 1998; LIGHT CURVES; PRESUPERNOVA EVOLUTION; UBVRI PHOTOMETRY; MASSIVE STARS; IIB SUPERNOVA; BLACK-HOLES; EXPLOSION; PROGENITOR AB SN 1997ef has been recognized as a peculiar supernova from its light curve and spectral properties. The object was classified as a Type Ic supernova (SN Ic) because its spectra were dominated by broad absorption lines of oxygen and iron, lacking any clear signs of hydrogen or helium line features. The light curve is very different from that of previously known SNe Ic, showing a very broad peak and a slow tail. The strikingly broad line features in the spectra of SN 1997ef, which were also seen in the hypernova SN 1998bw, suggest the interesting possibility that SN 1997ef may also be a hypernova. The light curve and spectra of SN 1997ef were modeled first with a standard SN Ic model assuming an ordinary kinetic energy of explosion E(K) = 10(51) ergs. The explosion of a CO star of mass M(CO) approximate to 6 M(circle dot) gives a reasonably good fit to the light curve but clearly fails to reproduce the broad spectral features. Then, models with larger masses and energies were explored. Both the light curve and the spectra of SN 1997ef are much better reproduced by a C+O star model with E(K) = 8 x 10(51) ergs and M(CO) = 10 M(circle dot). Therefore, we conclude that SN 1997ef is very likely a hypernova on the basis of its kinetic energy of explosion. Finally, implications for the deviation from spherical symmetry are discussed in an effort to improve the fits to the observations. C1 Nihon Univ, Coll Sci & Technol, Dept Phys, Chiyoda Ku, Tokyo 1018308, Japan. Univ Tokyo, Dept Astron, Sch Sci, Bunkyo Ku, Tokyo 1130033, Japan. Univ Tokyo, Res Ctr Early Univ, Sch Sci, Bunkyo Ku, Tokyo 1130033, Japan. Osserv Astron Trieste, I-34131 Trieste, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Victoria, Victoria, BC, Canada. Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA. RP Iwamoto, K (reprint author), Nihon Univ, Coll Sci & Technol, Dept Phys, Chiyoda Ku, Tokyo 1018308, Japan. RI Nomoto, Ken'ichi/A-4393-2011 NR 63 TC 142 Z9 142 U1 0 U2 3 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 MAY 10 PY 2000 VL 534 IS 2 BP 660 EP 669 DI 10.1086/308761 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 320ZA UT WOS:000087429400013 ER PT J AU Tuthill, PG Danchi, WC Hale, DS Monnier, JD Townes, CH AF Tuthill, PG Danchi, WC Hale, DS Monnier, JD Townes, CH TI Near- and mid-infrared subarcsecond structure of the dusty symbiotic star R Aquarii SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : symbiotic; circumstellar matter; stars : AGB and post-AGB; stars : individual (R Aquarii); stars : mass loss; techniques : interferometric ID APERTURE SYNTHESIS; BINARY-SYSTEM; MIRA; RESOLUTION; TEMPERATURE; DIAMETER; LEONIS; GRAINS; IMAGES; PHASE AB The results of a high-resolution interferometric campaign targeting the symbiotic long-period variable (LPV) R Aqr are reported. With both near-infrared measurements on baselines out to 10 m and midinfrared data extending to 32 m, we have been able to measure the characteristic sizes of regions from the photosphere of the LPV and its extended molecular atmosphere out to the cooler circumstellar dust shell. The near-infrared data were taken using aperture-masking interferometry on the Keck I telescope and show R Aqr to be partially resolved for wavelengths out to 2.2 mu m but with a marked enlargement, possibly due to molecular opacity, at 3.1 mu m. Mid-infrared interferometric measurements were obtained with the Univeristy of California, Berkeley, infrared spatial interferometer (ISI) operating at 11.15 mu m from 1992 to 1999. Although this data set is somewhat heterogeneous with incomplete coverage of the Fourier plane and sampling of the pulsation cycle, clear changes in the mid-infrared brightness distribution were observed, both as a function of position angle on the sky and as a function of pulsation phase. Spherically symmetric radiative transfer calculations of uniform-outflow dust shell models produce brightness distributions and spectra which partially explain the data; however, limitations to this approximation are noted. Evidence for significant deviation from circular symmetry was found in the mid-infrared and more tentatively at 3.08 mu m in the near-infrared; however, no clear detection of binarity or of non-LPV elements in the symbiotic system is reported. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Sydney, Chatterton Astron Dept, Sch Phys, Sydney, NSW 2006, Australia. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Tuthill, PG (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NR 50 TC 41 Z9 41 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2000 VL 534 IS 2 BP 907 EP 914 DI 10.1086/308782 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 320ZA UT WOS:000087429400034 ER PT J AU Croft, RAC Dave, R Hernquist, L Katz, N AF Croft, RAC Dave, R Hernquist, L Katz, N TI Simulating the effects of intergalactic gray dust SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; dust, extinction; large-scale structure of universe ID LYMAN-ALPHA FOREST; IA SUPERNOVAE; SCALE STRUCTURE; TREESPH AB Using a high-resolution cosmological hydrodynamic simulation we present a method to constrain extinction due to intergalactic gray dust based on the observed magnitudes of distant Type Ia supernovae. We apply several simple prescriptions to relate the intergalactic dust density to the gas density in the simulation, thereby obtaining dust extinctions that may be directly compared with the observed distribution of supernova magnitudes. Our analysis is sensitive to the spatial distribution of gray dust but is not dependent on its intrinsic properties, such as its opacity or grain size. We present an application of our technique to the supernova data of Perlmutter et al., who find that their high-redshift sample is similar to 0.2 mag fainter than the expectation for a nonaccelerating, low-density universe. We find that for gray dust to be responsible, it must be distributed quite smoothly (e.g., tracing intergalactic gas). More realistic dust distributions, such as dust tracing the metal density, are inconsistent with observations at the 1.5-2 sigma level. Upcoming observations and improved modeling of the dust distribution should lead to stronger constraints on intergalactic gray dust extinction. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA. RP Croft, RAC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Croft, Rupert/N-8707-2014 OI Croft, Rupert/0000-0003-0697-2583 NR 20 TC 10 Z9 10 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2000 VL 534 IS 2 BP L123 EP L126 DI 10.1086/312666 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 320ZB UT WOS:000087429500002 ER PT J AU McNamara, BR Wise, M Nulsen, PEJ David, LP Sarazin, CL Bautz, M Markevitch, M Vikhlinin, A Forman, WR Jones, C Harris, DE AF McNamara, BR Wise, M Nulsen, PEJ David, LP Sarazin, CL Bautz, M Markevitch, M Vikhlinin, A Forman, WR Jones, C Harris, DE TI Chandra X-ray observations of the Hydra A cluster: An interaction between the radio source and the X-ray-emitting gas SO ASTROPHYSICAL JOURNAL LA English DT Article DE cooling flows; galaxies : clusters : individual (Hydra A) ID STAR-FORMATION; COOLING-FLOW; A CLUSTER; GALAXY; LOBES; SAMPLE; ROSAT; DISK AB We present Chandra X-ray observations of the Hydra A cluster of galaxies, and we report the discovery of structure in the central 80 kpc of the cluster's X-ray-emitting gas. The most remarkable structures are depressions in the X-ray surface brightness, similar to 25-35 kpc in diameter, that are coincident with Hydra A's radio lobes. The depressions are nearly devoid of X-ray-emitting gas, and there is no evidence for shock-heated gas surrounding the radio lobes. We suggest that the gas within the surface brightness depressions was displaced as the radio lobes expanded subsonically, leaving cavities in the hot atmosphere. The gas temperature declines from 4 keV at 70 kpc to 3 keV in the inner 20 kpc of the brightest cluster galaxy (BCG), and the cooling time of the gas is similar to 600 Myr in the inner 10 kpc. These properties are consistent with the presence of an similar to 34 M. yr(-1) cooling Row within a 70 kpc radius. Bright X-ray emission is present in the BCG surrounding a recently accreted disk of nebular emission and young stars. The star formation rate is commensurate with the cooling rate of the hot gas within the volume of the disk, although the sink for the material that may be cooling at larger radii remains elusive. A bright, unresolved X-ray source is present in the BCG's nucleus, coincident with the radio core. Its X-ray spectrum is consistent with a power law absorbed by a foreground N-H similar or equal to 4 x 10(22) cm(-2) column of hydrogen. This column is roughly consistent with the hydrogen column seen in absorption toward the less than or similar to 24 pc diameter VLBA radio source. Apart from the point source, no evidence for excess X-ray absorption above the Galactic column is found. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Space Res Ctr, Cambridge, MA 02139 USA. Univ Wollongong, Dept Engn Phys, Wollongong, NSW 2522, Australia. Univ Virginia, Dept Astron, Charlottesville, VA 22903 USA. RP McNamara, BR (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 15 TC 312 Z9 313 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2000 VL 534 IS 2 BP L135 EP L138 DI 10.1086/312662 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 320ZB UT WOS:000087429500005 ER PT J AU Fiore, F La Franca, F Vignali, C Comastri, A Matt, G Perola, GC Cappi, M Elvis, M Nicastro, F AF Fiore, F La Franca, F Vignali, C Comastri, A Matt, G Perola, GC Cappi, M Elvis, M Nicastro, F TI Spectroscopic identification of ten faint hard X-ray sources discovered by Chandra SO NEW ASTRONOMY LA English DT Article DE X-rays : galaxies; diffuse radiation; quasars; galaxies : starburst ID EARLY-TYPE GALAXIES; GALACTIC NUCLEI; EMISSION; STARBURST; CONSTRAINTS; ACCRETION; NGC-6240; BEPPOSAX; OBJECTS; AGNS AB We report optical spectroscopic identifications of 10 hard (2-10 keV) X-ray selected sources discovered by Chandra. The X-ray flux of the sources ranges between 1.5 and 25 x 10(-14) erg cm(-2) s(-1), the lower value being 3 times fainter than in previous BeppoSAX and ASCA surveys. Their R band magnitudes are in the range 12.8-22. Six of the Chandra sources are broad line quasars with redshifts between 0.42 and 1.19, while the optical identification of the remaining four is quite varied: two are X-ray obscured, emission line AGN at z = 0.272 and z = 0.683, one is a starburst galaxy at z = 0.016 and one, most unusually, is an apparently normal galaxy at z = 0.158. These findings confirm and extend down to fainter X-ray fluxes the BeppoSAX results, in providing samples with a wide range of X-ray and optical properties. The ratio between the soft X-ray and the optical luminosity of the z = 0.158 galaxy is a factor at least 30 higher than that of normal galaxies, and similar to those of AGN. The high X-ray luminosity and the lack of optical emission lines suggest an AGN in which either continuum beaming dominates, or emission lines are obscured or not efficiently produced. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Osservatorio Astron Roma, I-00044 Monteporzio Catone, Italy. BeppoSAX Sci Data Ctr, I-00131 Rome, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Roma Tre, Dipartimento Fis, I-00146 Rome, Italy. Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy. CNR, Ist Tecnol & Studio Radiaz Extraterr, I-40129 Bologna, Italy. RP Fiore, F (reprint author), Osservatorio Astron Roma, Via Frascati 33, I-00044 Monteporzio Catone, Italy. RI La Franca, Fabio/G-9631-2012; Vignali, Cristian/J-4974-2012; Cappi, Massimo/F-4813-2015; Comastri, Andrea/O-9543-2015; OI Vignali, Cristian/0000-0002-8853-9611; Comastri, Andrea/0000-0003-3451-9970; Cappi, Massimo/0000-0001-6966-8920; Nicastro, Fabrizio/0000-0002-6896-1364; La Franca, Fabio/0000-0002-1239-2721; Fiore, Fabrizio/0000-0002-4031-4157 NR 49 TC 70 Z9 70 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1384-1092 J9 NEW ASTRON JI New Astron. PD MAY 9 PY 2000 VL 5 IS 3 BP 143 EP 153 DI 10.1016/S1384-1076(00)00017-8 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 333AH UT WOS:000088106200001 ER PT J AU Abu-Zayyad, T Belov, K Bird, DJ Boyer, J Cao, Z Catanese, M Chen, GF Clay, RW Covault, CE Cronin, JW Dai, HY Dawson, BR Elbert, JW Fick, BE Fortson, LF Fowler, JW Gibbs, KG Glasmacher, MAK Green, KD Ho, Y Huang, A Jui, CC Kidd, MJ Kieda, DB Knapp, BC Ko, S Larsen, CG Lee, W Loh, EC Mannel, EJ Matthews, J Matthews, JN Newport, BJ Nitz, DF Ong, RA Simpson, KM Smith, JD Sinclair, D Sokolsky, P Sommers, P Song, C Tang, JKK Thomas, SB van der Velde, JC Wiencke, LR Wilkinson, CR Yoshida, S Zhang, XZ AF Abu-Zayyad, T Belov, K Bird, DJ Boyer, J Cao, Z Catanese, M Chen, GF Clay, RW Covault, CE Cronin, JW Dai, HY Dawson, BR Elbert, JW Fick, BE Fortson, LF Fowler, JW Gibbs, KG Glasmacher, MAK Green, KD Ho, Y Huang, A Jui, CC Kidd, MJ Kieda, DB Knapp, BC Ko, S Larsen, CG Lee, W Loh, EC Mannel, EJ Matthews, J Matthews, JN Newport, BJ Nitz, DF Ong, RA Simpson, KM Smith, JD Sinclair, D Sokolsky, P Sommers, P Song, C Tang, JKK Thomas, SB van der Velde, JC Wiencke, LR Wilkinson, CR Yoshida, S Zhang, XZ TI Evidence for changing of cosmic ray composition between 10(17) and 10(18) eV from multicomponent measurements SO PHYSICAL REVIEW LETTERS LA English DT Article ID FLYS EYE; ENERGIES; SPECTRUM AB The average mass composition of cosmic rays with primary energies between 10(17) and 10(18) eV has been studied using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum and the muon density as a function of energy. The results show that the composition is changing from a heavy to lighter mix as the energy increases. C1 Univ Utah, High Energy Astrophy Inst, Salt Lake City, UT 84112 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Columbia Univ, Nevis Lab, Irvington, NY 10533 USA. Univ Adelaide, Adelaide, SA 5005, Australia. Univ Illinois, Urbana, IL 61801 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Micigan Tech Univ, Dept Phys, Houghton, MI 49931 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. So Univ, Dept Phys, Baton Rouge, LA 70801 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. RP Univ Utah, High Energy Astrophy Inst, Salt Lake City, UT 84112 USA. RI Song, Chihwa/A-3455-2008; Belov, Konstantin/D-2520-2013; OI Matthews, James/0000-0002-1832-4420 NR 22 TC 112 Z9 113 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 8 PY 2000 VL 84 IS 19 BP 4276 EP 4279 DI 10.1103/PhysRevLett.84.4276 PG 4 WC Physics, Multidisciplinary SC Physics GA 312KC UT WOS:000086941600006 ER PT J AU Meibom, A Desch, SJ Krot, AN Cuzzi, JN Petaev, MI Wilson, L Keil, K AF Meibom, A Desch, SJ Krot, AN Cuzzi, JN Petaev, MI Wilson, L Keil, K TI Large-scale thermal events in the solar nebula: Evidence from Fe,Ni metal grains in primitive meteorites SO SCIENCE LA English DT Article ID ACCRETION DISKS; CARBONACEOUS CHONDRITES; TEMPERATURE; HISTORY AB Chemical zoning patterns in some iron, nickel metal grains from CH carbonaceous chondrites imply formation at temperatures from 1370 to 1270 kelvin by condensation from a solar nebular gas cooling at a rare of similar to 0.2 kelvin per hour. This cooling rate requires a Large-scale thermal event in the nebula, in contrast to the localized, transient heating events inferred for chondrule formation. In our model, mass accretion through the protoplanetary disk caused Large-scale evaporation of precursor dust near its midplane inside of a few astronomical units. Gas convectively moved from the midplane to cooler regions above it, and the metal grains condensed in these parcels of rising gas. C1 Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Lancaster, Inst Environm & Nat Sci, Dept Environm Sci, Lancaster LA1 4YQ, England. Univ Hawaii Manoa, Hawaii Ctr Volcanol, Honolulu, HI 96822 USA. RP Meibom, A (reprint author), Stanford Univ, Dept Geol & Environm Sci, Bldg 320,Lomita Mall, Stanford, CA 94305 USA. NR 27 TC 56 Z9 57 U1 1 U2 4 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 5 PY 2000 VL 288 IS 5467 BP 839 EP 841 DI 10.1126/science.288.5467.839 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 311DN UT WOS:000086869600031 ER PT J AU Aronson, RB Precht, WF Macintyre, IG Murdoch, TJT AF Aronson, RB Precht, WF Macintyre, IG Murdoch, TJT TI Ecosystems - Coral bleach-out in Belize SO NATURE LA English DT Article ID REEF C1 Dauphin Isl Sea Lab, Dauphin Island, AL 36528 USA. PBS&J, Miami, FL 33172 USA. Smithsonian Inst, Museum Natl Hist Nat, Dept Paleobiol, Washington, DC 20560 USA. RP Aronson, RB (reprint author), Dauphin Isl Sea Lab, 1-1 Bienville Blvd, Dauphin Island, AL 36528 USA. NR 14 TC 83 Z9 95 U1 1 U2 14 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAY 4 PY 2000 VL 405 IS 6782 BP 36 EP 36 DI 10.1038/35011132 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 311TK UT WOS:000086901600039 PM 10811207 ER PT J AU Rice, RA Greenberg, R AF Rice, RA Greenberg, R TI Cacao cultivation and the conservation of biological diversity SO AMBIO LA English DT Article ID LOS-TUXTLAS; LANDSCAPE CHANGES; SHADE COFFEE; FOREST; MEXICO; COCOA; PLANTATIONS; HABITATS; TREES; ORGANIZATION AB Cacao (Theobroma cacao) is a crop of the humid lowland tropics produced largely by small-scale producers and often on farms with a canopy of shade trees. Where a diverse shaded canopy is used, cacao farms support higher levels of biological diversity than most other tropical crops. A host of viral and fungal diseases, loss of soil fertility, and numerous socioeconomic problems facing producers, often makes cacao production locally unsustainable. Continued clearing of new lands threatens biodiversity. Moreover, new frontiers for cacao expansion are rapidly disappearing. Such problems can be addressed by increasing the long-term productivity of existing cacao farms and restoring abandoned lands. Improved shade management offers guidance along this path. Institutions involved with cocoa should establish collaborations with groups concerned with development, environmental protection, and most importantly producers themselves to pursue a program of research, extension and policy initiatives focused on the ecologically and economically sustainable cacao production on farms with a diverse shade canopy. C1 Smithsonian Migratory Bird Ctr, Washington, DC 20008 USA. RP Rice, RA (reprint author), Smithsonian Migratory Bird Ctr, Natl Zool Pk, Washington, DC 20008 USA. EM rarice@igc.org; anfbird@erols.com NR 64 TC 164 Z9 177 U1 10 U2 66 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0044-7447 EI 1654-7209 J9 AMBIO JI Ambio PD MAY PY 2000 VL 29 IS 3 BP 167 EP 173 DI 10.1579/0044-7447-29.3.167 PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 325HP UT WOS:000087670400009 ER PT J AU Catlos, EJ Sorensen, SS Harrison, TM AF Catlos, EJ Sorensen, SS Harrison, TM TI Th-Pb ion-microprobe dating of allanite SO AMERICAN MINERALOGIST LA English DT Article ID RARE-EARTH ELEMENTS; ACCESSORY MINERALS; SOUTHERN CALIFORNIA; MAGMATIC EPIDOTE; MONAZITE; EVOLUTION; METAMORPHISM; SYSTEMATICS; GRANITE; ORIGIN AB Allanite, which is a common accessory mineral in a wide variety of rock types, typically contains high concentrations of Th and U; thus, an in-situ method of U-Th-Pb dating of this phase would have broad application. We describe a method to permit Th-Pb ages of allanite to be determined with approximately +/-10% accuracy using a high-resolution ion microprobe. Knowledge of the composition and substitution mechanisms of this complex mineral is key to understanding the relative ionization efficiencies of Th+ and Pb+. The chemical compositions of three allanite samples used as age standards (Cima d'Asta Pluton, 275.5 +/- 1.5 Ma; Atesina Volcanic Complex, 276.3 +/- 2.2 Ma; La Posta Pluton, 94 +/- 2 Ma) were determined using an electron microprobe, permitting an assessment of matrix effects on ionization. An ion-microprobe calibration curve involving elemental and oxide species of Th and ph (i.e., Pb-208*/Th'(+) VS. ThO2+/Th+) yields highly scattered apparent ages when allanite age standards with different Fe contents are used. However, a three-dimensional plot of Pb-208*/Th+ VS. ThO2+/Th+ vs. FeO+/SiO+ improves the accuracy of the calibration to about +/-10%. Even though this level of uncertainty is substantially greater than that expected for U-Th-Pb ion-microprobe analyses of zircon or monazite, Th-Pb ages of allanite can still be used to address important geologic questions. We used this method to date two metamorphic allanite grains from the footwall of the Main Central Thrust, Nepal Himalaya, and an allanite grain from the Pacoima Canyon pegmatite, California. Allanite inclusions in garnet from Nepal yield significantly older ages than the coexisting monazite, indicating that allanite formation in these rocks records a previous metamorphic cycle that predates slip along the fault. The Pacoima Canyon allanite grain yields a younger age than that reported for zircon, implying Pb loss during cooling of the pegmatite. C1 Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. Natl Museum Nat Hist, Smithsonian Inst, Dept Mineral Sci, Washington, DC 20560 USA. RP Catlos, EJ (reprint author), Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. EM catlos@argon.ess.ucla.edu RI Catlos, Elizabeth/B-7943-2011; Harrison, Timothy/E-7443-2012; UCLA, SIMS/A-1459-2011 NR 65 TC 58 Z9 62 U1 2 U2 9 PU MINERALOGICAL SOC AMER PI CHANTILLY PA 3635 CONCORDE PKWY STE 500, CHANTILLY, VA 20151-1125 USA SN 0003-004X EI 1945-3027 J9 AM MINERAL JI Am. Miner. PD MAY-JUN PY 2000 VL 85 IS 5-6 BP 633 EP 648 PG 16 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 313GV UT WOS:000086992700001 ER PT J AU Grice, JD Dunn, PJ AF Grice, JD Dunn, PJ TI Crystal-structure determination of pinalite SO AMERICAN MINERALOGIST LA English DT Article ID THORIKOSITE AB The crystal structure of pinalite, Pb3WO5Cl2, is orthorhombic Amam, with a = 11.073(2), b = 13.067(3), c = 5.617(1) Angstrom, V = 812.81(3) Angstrom(3) and Z = 4. It has been refined to an R index of 0.049 on the basis of 593 unique, observed reflections. There are two crystallographically distinct Pb cations with different coordinations: Pbl has eightfold-coordination with ligands of 4 Cl atoms, 4 O atoms, and one stereoactive lone-pair, whereas Pb2 has ninefold-coordination with ligands of 4 Cl atoms and 5 O atoms. The W cation has fivefold-coordination with 5 O ligands. The pinalite structure is layered parallel to (100) with Pb-O-Cl layers interleaved with Pb-W-O layers. Pinalite belongs to the bismuth oxychloride group of structures. The Pb-O-Cl layer of pinalite duplicates the basic structure of thorikosite and the Pb-W-O layer of pinalite is able to conform to this fundamental cell through differences in the two Pb coordinations and a unique W coordination. Similarly the structures of nadorite and kettnerite are also shown to replicate the basic bismuth oxychloride structure. C1 Canadian Museum Nat, Ottawa, ON K1P 6P4, Canada. Smithsonian Inst, Dept Mineral Sci, Washington, DC 20560 USA. RP Grice, JD (reprint author), Canadian Museum Nat, POB 3443 Stn D, Ottawa, ON K1P 6P4, Canada. NR 11 TC 12 Z9 12 U1 1 U2 1 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 2000 VL 85 IS 5-6 BP 806 EP 809 PG 4 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 313GV UT WOS:000086992700020 ER PT J AU Rommel, S Reynolds, JE AF Rommel, S Reynolds, JE TI Diaphragm structure and function in the Florida manatee (Trichechus manatus latirostris) SO ANATOMICAL RECORD LA English DT Article DE manatee; Sirenia; diaphragm; transverse septum; buoyancy; functional morphology AB Relative to many other mammals, little is known about the functional morphology of the four extant species of the order Sirenia. In this study, 166 Florida manatee (Trichechus manatus latirostris) carcasses fresh enough to collect detailed anatomical information were examined to describe the gross anatomy of the diaphragm. Our results show that the Florida manatee's diaphragm differs from those of other mammals in that it: lies in a dorsal plane, rather than in the more typical transverse plane; is located dorsal to the heart and does not attach to the sternum; and attaches medially at the "I"-shaped central tendon to bony projections extending ventrally from the vertebral bodies, forming two distinct hemidiaphragms. The manatee's transverse septum is a separate structure that lies at a right angle to the diaphragm and separates the heart from the liver and other viscera. The extreme muscularity of the diaphragm and the ability of manatees to adjust their position in the water column with minimal external movement suggest that diaphragmatic contractions may change the volume of each pleural cavity to affect buoyancy, roll, and pitch. We also hypothesize that such contractions, in concert with contractions of powerful abdominal muscles, may compress gas in the massive large intestine, and thereby also contribute to buoyancy control. Anat Rec 259: 41-51, 2000. (C) 2000 Wiley-Liss, Inc. C1 Florida Game & Fresh Water Fish Commiss, Florida Marine Res Inst, Marine Mammal Pathobiol Lab, St Petersburg, FL 33711 USA. Smithsonian Inst, Div Mammals, Washington, DC 20560 USA. Eckerd Coll, Dept Marine Sci, St Petersburg, FL 33711 USA. RP Rommel, S (reprint author), Florida Game & Fresh Water Fish Commiss, Florida Marine Res Inst, Marine Mammal Pathobiol Lab, 3700 54th Ave S, St Petersburg, FL 33711 USA. NR 31 TC 22 Z9 24 U1 2 U2 11 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0003-276X J9 ANAT REC JI Anat. Rec. PD MAY 1 PY 2000 VL 259 IS 1 BP 41 EP 51 PG 11 WC Anatomy & Morphology SC Anatomy & Morphology GA 308EN UT WOS:000086697700005 PM 10760742 ER PT J AU Ralls, K Ballou, JD Rideout, BA Frankham, R AF Ralls, K Ballou, JD Rideout, BA Frankham, R TI Genetic management of chondrodystrophy in California condors SO ANIMAL CONSERVATION LA English DT Article ID INBREEDING DEPRESSION; CAPTIVE POPULATIONS; CONSERVATION; DEFECTS AB Five out of 169 fertile California condor (Gymnogyps californianus) eggs laid in captivity have exhibited chondrodystrophy, a lethal form of dwarfism. Pedigree records indicate that this chondrodystrophy, like similar conditions in chickens, turkeys and quail, is probably inherited as an autosomal, recessive allele. We estimate that the frequency of this putative allele is about 9%. This high frequency is probably due to a founder effect. We consider three management options for the allele: ignoring it, eliminating it by selection and minimizing its phenotypic manifestation by avoiding matings between possible carriers. We recommend minimizing its phenotypic expression because an unacceptably large proportion of condors (up to 78 out of 146) would be prevented from breeding under a selection strategy designed to eliminate the allele. We predict that many captive populations will prove similar to the California condor population in that it will prove inadvisable or impractical to select against one or more deleterious alleles detected in the population. C1 Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. Zool Soc San Diego, San Diego, CA 92112 USA. Macquarie Univ, N Ryde, NSW 2109, Australia. RP Ralls, K (reprint author), Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. NR 36 TC 36 Z9 36 U1 8 U2 38 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 1367-9430 J9 ANIM CONSERV JI Anim. Conserv. PD MAY PY 2000 VL 3 BP 145 EP 153 DI 10.1111/j.1469-1795.2000.tb00239.x PN 2 PG 9 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 344KF UT WOS:000088757200007 ER PT J AU Soon, W Posmentier, E Baliunas, S AF Soon, W Posmentier, E Baliunas, S TI Climate hypersensitivity to solar forcing? SO ANNALES GEOPHYSICAE-ATMOSPHERES HYDROSPHERES AND SPACE SCIENCES LA English DT Article DE meteorology and atmospheric dynamics; (climatology, general or miscellaneous); solar physics, astrophysics, and astronomy; (ultraviolet emissions) ID TEMPERATURE; VARIABILITY; IRRADIANCE; CYCLE; CLOUD; CIRCULATION; TROPOSPHERE; CIRRUS; OZONE; GCM AB We compare the equilibrium climate responses of a quasi-dynamical energy balance model to radiative forcing by equivalent changes in CO2, solar total irradiance (S-tot) and solar UV (S-UV) The response is largest in the S-UV case, in which the imposed UV radiative forcing is preferentially absorbed in the layer above 250 mb, in contrast to the weak response from global-columnar radiative loading by increases in CO2 or S-tot. The hypersensitive response of the climate system to solar UV forcing is caused by strongly coupled feedback involving vertical static stability, tropical thick cirrus ice clouds and stratospheric ozone. This mechanism offers a plausible explanation of the apparent hypersensitivity of climate to solar forcing, as suggested by analyses of recent climatic records. The model hypersensitivity strongly depends on climate parameters, especially cloud radiative properties, but is effective for arguably realistic values of these parameters. The proposed solar forcing mechanism should be further confirmed using other models (e.g., general circulation models) that may better capture radiative and dynamical couplings of the troposphere and stratosphere. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Pertanian Malaysia, Fac Sci & Environm Studies, Serdang 43400, Selangor, Malaysia. Long Isl Univ, Dept Phys, Brooklyn, NY 11201 USA. Long Isl Univ, Dept Math, Brooklyn, NY 11201 USA. RP Soon, W (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 32 TC 21 Z9 23 U1 0 U2 4 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0992-7689 J9 ANN GEOPHYS-ATM HYDR JI Ann. Geophys.-Atmos. Hydrospheres Space Sci. PD MAY PY 2000 VL 18 IS 5 BP 583 EP 588 DI 10.1007/s00585-000-0583-z PG 6 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA 329AM UT WOS:000087884000009 ER PT J AU Shapiro, LH AF Shapiro, LH TI Reproductive costs to heterospecific mating between two hybridizing katydids (Orthoptera : Tettigoniidae) SO ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA LA English DT Article DE Tettigoniidae; fecundity; hybridization; postmating isolation; reproductive isolation ID CONSPECIFIC SPERM PRECEDENCE; GEOGRAPHIC-VARIATION; SEXUAL SELECTION; BODY SIZE; CRICKETS; DROSOPHILA; GRYLLIDAE; ZONES AB Animal taxa meeting in hybrid zones often exhibit partial reproductive isolation. This isolation may result from a variety of causes both before mating (e.g., incompatibilities in courtship behaviors) and subsequent to mating. Understanding the factors effecting reproductive isolation in hybrid zones can offer important insights into the process of speciation and the maintenance of species boundaries. The katydids Orchelimum nigripes Scudder and O. pulchellum Davis (Orthoptera: Tettigoniidae) form 2 hybrid zones in the eastern United States. I carried out breeding studies in the laboratory using animals from pure O. nigripes and O. pulchellum populations in the vicinity of one of these hybrid zones to examine possible modes of postmating reproductive isolation. The number of eggs produced by females mated to heterospecific males was dramatically lower than that of females mated conspecifically, but there was no evidence of any differences in hutch rate or offspring viability between egg clutches from heterospecific and conspecific crosses. Hatch rate, offspring viability, development time, and adult weight of hybrid progenies were all intermediate relative to corresponding values for progenies resulting from the 2 types of conspecific matings, although most of the differences between hybrids and each of the 2 classes of nonhybrid progenies were not statistically significant. The reduced oviposition of heterospecifically mated females suggests that females mated to heterospecific males do not receive the necessary stimulation to trigger oocyte maturation or oviposition behavior. The results reported here show that although some females will mate with heterospecific males, these matings tend to result in substantially reduced reproductive success relative to conspecific matings. C1 SUNY Stony Brook, Dept Ecol & Evolut, Stony Brook, NY 11794 USA. RP Shapiro, LH (reprint author), Smithsonian Inst, Natl Zool Pk, Mol Genet Lab, 3001 Connecticut Ave NW, Washington, DC 20008 USA. NR 36 TC 6 Z9 7 U1 1 U2 4 PU ENTOMOL SOC AMER PI LANHAM PA 9301 ANNAPOLIS RD, LANHAM, MD 20706 USA SN 0013-8746 J9 ANN ENTOMOL SOC AM JI Ann. Entomol. Soc. Am. PD MAY PY 2000 VL 93 IS 3 BP 440 EP 446 DI 10.1603/0013-8746(2000)093[0440:RCTHMB]2.0.CO;2 PG 7 WC Entomology SC Entomology GA 359VC UT WOS:000089631900014 ER PT J AU Havel, TF Somaroo, SS Tseng, CH Cory, DG AF Havel, TF Somaroo, SS Tseng, CH Cory, DG TI Principles and demonstrations of quantum information processing by NMR spectroscopy SO APPLICABLE ALGEBRA IN ENGINEERING COMMUNICATION AND COMPUTING LA English DT Article DE nuclear magnetic resonance; quantum computation; quantum error correcting codes; pseudo-pure states; product operator formalism ID NUCLEAR-MAGNETIC-RESONANCE; PRODUCT OPERATOR-FORMALISM; GEOMETRIC ALGEBRA; PULSE EXPERIMENTS; COMPUTATION; STATES; ALGORITHM; IMPLEMENTATION; INEQUALITIES; SPACETIME AB This paper surveys our recent research on quantum information processing by nuclear magnetic resonance (NMR) spectroscopy. We begin with a geometric introduction to the NMR of an ensemble of indistinguishable spins, and then show how this geometric interpretation is contained within an algebra of multispin product operators. This algebra is used throughout the rest of the paper to demonstrate that it provides a facile framework within which to study quantum information processing more generally. The implementation of quantum algorithms by NMR depends upon the availability of special kinds of mixed states, called pseudo-pure states, and we consider a number of different methods for preparing these states, along with analyses of how they scale with the number of spins. The quantum-mechanical nature of processes involving such macroscopic pseudo-pure states also is a matter of debate, and in order to discuss this issue in concrete terms we present the results of NMR experiments which constitute a macroscopic analogue Hardy's paradox. Finally, a detailed product operator description is given of recent NMR experiments which demonstrate a three-bit quantum error correcting code, using field gradients to implement a precisely-known decoherence model. C1 Harvard Univ, Sch Med, BCMP, Boston, MA 02115 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Cambridge, MA 02139 USA. RP Havel, TF (reprint author), Harvard Univ, Sch Med, BCMP, Boston, MA 02115 USA. NR 58 TC 20 Z9 21 U1 0 U2 6 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0938-1279 J9 APPL ALGEBR ENG COMM JI Appl. Algebr. Eng. Commun. Comput. PD MAY PY 2000 VL 10 IS 4-5 BP 339 EP 374 DI 10.1007/s002000050135 PG 36 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA 321RL UT WOS:000087468400007 ER PT J AU Schwartz, GT AF Schwartz, GT TI Enamel thickness and the helicoidal wear plane in modern human mandibular molars SO ARCHIVES OF ORAL BIOLOGY LA English DT Article DE enamel thickness; helicoid occlusion; molar function; mastication; gradients ID DENTAL OCCLUSION; BITE FORCES; PRIMATES; ATTRITION; EVOLUTION; MUSCLE; TEETH AB Helicoid occlusion has long been recognized as a feature characterizing the human dentition and has been viewed as an important morphological marker in the transition from Australopitheclus to Homo. The hallmark of helicoidal wear is a buccal wear slope in anterior mandibular molars (and a corresponding lingual slope of wear in anterior maxillary molars) reversing to a flat or lingual-oriented one in posterior mandibular molars. If localized increases in enamel thickness are taken as evidence of an adaptation to increased wear resistance, then data on enamel thickness in unworn molars can be used to assess whether the region of greatest wear changes from anterior to posterior in such a way as to provide evidence for the helicoidal wear plane being a structural feature of the orofacial skeleton. Such a hypothesis was supported in a previous study on enamel thickness in modern human maxillary molars. As maxillary and mandibular precisely interdigitate, it is reasonable to expect that a similar pattern of enamel thickness distribution should be present in mandibular molars. To test this, data on the distribution of enamel thickness across functionally relevant regions of the crown were corrected on a sample of twenty-nine completely unworn mandibular molars. Results suggest that enamel thickness increases slightly posteriorly but no evidence exists for morphological changes along the mandibular molar series of modern humans to follow a trend towards providing additional tooth material in areas under greater wear in accordance with a helicoidal wear model. This suggests that the patterning of enamel thickness must be viewed in conjunction with other features, such as the biomechanical behaviour of molars during occlusion and axial molar angulation, to ascertain the precise anatomical determinants of this unique feature of the human dentition. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 George Washington Univ, Dept Anthropol, Washington, DC 20052 USA. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Schwartz, GT (reprint author), George Washington Univ, Dept Anthropol, 2110 G St,NW, Washington, DC 20052 USA. NR 35 TC 33 Z9 34 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0003-9969 J9 ARCH ORAL BIOL JI Arch. Oral Biol. PD MAY PY 2000 VL 45 IS 5 BP 401 EP 409 DI 10.1016/S0003-9969(00)00007-8 PG 9 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 303ZF UT WOS:000086457500007 PM 10739861 ER PT J AU Jarrett, TH Chester, T Cutri, R Schneider, S Skrutskie, M Huchra, JP AF Jarrett, TH Chester, T Cutri, R Schneider, S Skrutskie, M Huchra, JP TI 2MASS extended source catalog: Overview and algorithms SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : general; methods : data analysis; surveys; techniques : image processing techniques : miscellaneous; techniques : photometric ID FAINT GALAXIES; PHOTOMETRY; FIELD AB The Two Micron All Sky Survey (2MASS) will observe over 1,000,000 galaxies and extended Galactic sources covering the entire sky at wavelengths between 1 and 2 mu m. Most of these galaxies will be newly cataloged objects. The survey catalog will have both high completeness and reliability down to J = 15.0 mag and K(s) = 13.5 mag, equivalent to 1.6 and 2.9 mJy, respectively. Galaxies as small as 10 " are resolved, and those as large as similar to 2.'5 are fully imaged. 2MASS will discover galaxies never seen before in the "zone of avoidance" caused by the obscuring effects of Galactic dust and gas, limited only by the extreme number of stars at very low Galactic latitude, especially toward the Galactic center. This paper describes the basic algorithms used to detect and characterize extended sources in the 2MASS database and catalog. Critical procedures include tracking the point-spread function, image background removal, artifact removal, photometry and basic parameterization, star-galaxy discrimination, and object classification using a decision tree technique. We introduce and provide examples of the types of extended sources that 2MASS detects across the sky, including galaxies, Galactic nebulae and resolved stellar objects, multiple stars and clusters, and, finally, artifacts arising from bright stars and transient events. A future paper will provide a full statistical analysis and verification of the completeness, reliability, and integrity of the first release catalog, as well as some of the basic scientific results of the catalog, including galaxy colors, number counts, and redshift distribution. C1 CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Univ Massachusetts, Astron Program, Amherst, MA 01003 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Jarrett, TH (reprint author), CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Mail Stop 100-22, Pasadena, CA 91125 USA. EM jarrett@ipac.caltech.edu; tchester@ipac.caltech.edu; roc@ipac.caltech.edu; schneider@phast.umass.edu; skrutski@phast.umass.edu; huchra@cfa.harvard.edu NR 32 TC 581 Z9 597 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 2000 VL 119 IS 5 BP 2498 EP 2531 DI 10.1086/301330 PG 34 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 318YB UT WOS:000087311300045 ER PT J AU van den Ancker, ME Bouwman, J Wesselius, PR Waters, LBFM Dougherty, SM van Dishoeck, EF AF van den Ancker, ME Bouwman, J Wesselius, PR Waters, LBFM Dougherty, SM van Dishoeck, EF TI ISO spectroscopy of circumstellar dust in the Herbig Ae systems AB Aur and HD 163296 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : circumstellar matter; stars : emission-line, Be; stars : individual : AB Aur; stars : individual : HD 163296; stars : pre-main sequence; infrared : stars ID RADIO-CONTINUUM EMISSION; BETA-PICTORIS PHENOMENON; INTERMEDIATE-MASS STARS; AE/BE STARS; WAVELENGTH SPECTROMETER; INFRARED OBSERVATIONS; ACTIVE PHENOMENA; HIGH-RESOLUTION; YOUNG STARS; MU-M AB Using both the Short- and Long-wavelength Spectrometers on board the Infrared Space Observatory (ISO), we have obtained infrared spectra of the Herbig Ae systems AB Aur and HD 163296. In addition, we obtained ground-based N band images of HD 163296. Our results can be summarized as follows: (I) The main dust components in AB Am are amorphous silicates, iron oxide and PAHs; (2) The circumstellar dust in HD 163296 consists of amorphous silicates, iron oxide, water ice and a small fraction of crystalline silicates; (3) The infrared fluxes of HD 163296 are dominated by solid state features; (4) The colour temperature of the underlying continuum is much cooler in HD 163296 than in AB Aur, pointing to the existence of a population of very large (mm sized) dust grains in HD 163296; (5) The composition and degree of crystallization of circumstellar dust are poorly correlated with the age of the central star. The processes of crystallization and grain growth are also not necessarily coupled. This means that either the evolution of circumstellar dust in protoplanetary disks happens very rapidly (within a few Myr), or that this evolution is governed by factors other than stellar mass and age. C1 Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. SRON, Lab Space Res, NL-9700 AV Groningen, Netherlands. Katholieke Univ Leuven, Inst Sterrenkunde, B-3001 Heverlee, Belgium. Univ Calgary, Dept Phys & Astron, Calgary, AB T2N 1N4, Canada. Domin Radio Astrophys Observ, Penticton, BC V2A 6K3, Canada. Leiden Observ, NL-2300 RA Leiden, Netherlands. RP van den Ancker, ME (reprint author), Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. EM mario@astro.uva.nl NR 50 TC 64 Z9 64 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2000 VL 357 IS 1 BP 325 EP 329 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 321GD UT WOS:000087447000045 ER PT J AU Lang, WJ Masheder, MRW Dame, TM Thaddeus, P AF Lang, WJ Masheder, MRW Dame, TM Thaddeus, P TI The lambda-Orionis Ring in CO SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE ISM : clouds; Galaxy : structure; radio lines : ISM; ISM : molecules; ISM : bubbles ID RADIATION-DRIVEN IMPLOSION; 1ST GALACTIC QUADRANT; MOLECULAR CLOUDS; STAR FORMATION; DENSE CORES; DARK CLOUDS; COMPLEXES; GLOBULES; REGION; SYSTEM AB The results of a new CO(J=1-->0) survey of the ring of molecular clouds around the HII region Sh-2-264 and the lambda-Orionis OB-association are presented. The distribution of molecular gas closely approximates that of the dust seen in IRAS emission. The total molecular mass is 1.4 x 10(4) M.. The mass spectrum of the emission clumps is a power-law with index -1.8, similar to that observed in other star-forming regions. The kinematics of the ring are modelled, but its alignment close to the plane of the sky allows only very weak constraints on expansion velocity and the age of the system. The data are compared with previous surveys, and possible evolutionary schemes for the region discussed. C1 Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Masheder, MRW (reprint author), Univ Bristol, HH Wills Phys Lab, Tyndall Ave, Bristol BS8 1TL, Avon, England. EM Mike.Masheder@bristol.ac.uk NR 43 TC 21 Z9 21 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2000 VL 357 IS 3 BP 1001 EP 1012 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 328KX UT WOS:000087851000031 ER PT J AU Lorenzetti, D Giannini, T Nisini, B Benedettini, M Creech-Eakman, M Blake, GA van Dishoeck, EF Cohen, M Liseau, R Molinari, S Pezzuto, S Saraceno, P Smith, HA Spinoglio, L White, GJ AF Lorenzetti, D Giannini, T Nisini, B Benedettini, M Creech-Eakman, M Blake, GA van Dishoeck, EF Cohen, M Liseau, R Molinari, S Pezzuto, S Saraceno, P Smith, HA Spinoglio, L White, GJ TI Far infrared spectroscopy of FU Ori objects - ISO-LWS observations SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : circumstellar matter; stars : individual : FU Ori; infrared : ISM : lines and bands; infrared : stars ID MAIN-SEQUENCE STARS; LONG-WAVELENGTH SPECTROMETER; YOUNG STELLAR OBJECTS; FINE-STRUCTURE LINES; HERBIG AE/BE STARS; Z-CANIS MAJORIS; T-TAURI STARS; ORIONIS STARS; MASS-LOSS; PHOTODISSOCIATION REGIONS AB We present the results of the first spectrophotometric observations of a sample of FU Ori objects obtained with the Long Wavelength Spectrometer (LWS) on board the Infrared Space Observatory (ISO). The [OI] (63 mu m) and the [CII] (158 mu m) lines are commonly observed in all spectra (both ON and OFF source). The observational novelty is the presence in most of the sources of the transition of ionised nitrogen [NII] (122 mu m), which is not detected in other objects in a similar evolutionary phase. This line probes low ionisation and low density material not easily traced by other lines. Line intensities and intensity ratios are used along with model predictions to infer the prevailing mechanisms for line excitation. To reconcile our far-infrared spectroscopy with previous knowledge of these objects, the simultaneous presence of two components is required: well localised J-shocks, responsible for the [OI] emission, and an extended low density ionised medium produced by UV photons from the disc boundary layer, responsible for the [NII] and [CII] emission. A few molecular lines.(CO, OH, H(2)O) associated with relatively cold and dense peaks are revealed and their intensities are in good agreement with the proposed scenario. Other ionic lines ([OIII] and [NIII]) are detected in two sources in the Cyg OB7 region and likely trace the presence of nearby HII regions. C1 Osserv Astron Roma, I-00040 Monte Porzio Catone, Italy. Univ Roma La Sapienza, Inst Astron, I-00161 Rome, Italy. CNR, Area Ric Tor Vergata, Ist Fis Spazio Interplanetario, I-00133 Rome, Italy. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA. Stockholm Observ, S-13336 Saltsjobaden, Sweden. CALTECH, IPAC, Pasadena, CA USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Queen Mary Univ London, London E1 4NS, England. RP Lorenzetti, D (reprint author), Osserv Astron Roma, Via Frascati 33, I-00040 Monte Porzio Catone, Italy. EM dloren@coma.mporzio.astro.it RI Molinari, Sergio/O-4095-2016; OI Molinari, Sergio/0000-0002-9826-7525; Pezzuto, Stefano/0000-0001-7852-1971; Giannini, Teresa/0000-0002-0224-096X; Spinoglio, Luigi/0000-0001-8840-1551; , Brunella Nisini/0000-0002-9190-0113 NR 66 TC 18 Z9 18 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2000 VL 357 IS 3 BP 1035 EP 1044 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 328KX UT WOS:000087851000035 ER PT J AU Zheng, X Reid, MJ Moran, JM AF Zheng, X Reid, MJ Moran, JM TI Magnetic field structure of the cometary HII region G34.3+0.2 - Magnetic field structure of G34.3+0.2 SO ASTRONOMY & ASTROPHYSICS LA English DT Letter DE masers; polarization; stars : formation; ISM : individual objects : G34.3+0.2 ID H-II REGIONS; CHAMPAGNE PHASE; MASER EMISSION; OH MASER; W3(OH) AB We observed the hydroxyl (OH) masers in the ground-state 1665 and 1667 MHz transitions toward the cometary HII region G34.3+0.2 with the Very Long Baseline Array (VLBA). Our observations were sensitive to both right and left circular polarizations with a spectral resolution of 0.176 km s(-1) and an angular resolution of 8 x 31 mas. We detected 120 maser features in a region of 3 x 6 arcsec, including 15 Zeeman pairs separated by an average distance of only 2 mas were identified. The OH masers are associated with two newly formed stars in the G34.3+0.2 complex. One star ionizes a weak, ultra-compact HII region (source 8) and has a magnetic field orientation predominantly away from us. The other star, or stars, power the dominant cometary HII region (source C) and the magnetic field along the northern rim of the cometary source is directed toward us. C1 Nanjing Univ, Dept Astron, Nanjing 210093, Peoples R China. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Zheng, X (reprint author), Nanjing Univ, Dept Astron, Nanjing 210093, Peoples R China. NR 20 TC 15 Z9 15 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2000 VL 357 IS 3 BP L37 EP L40 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 328KX UT WOS:000087851000001 ER PT J AU Mahdavi, A Bohringer, H Geller, MJ Ramella, M AF Mahdavi, A Bohringer, H Geller, MJ Ramella, M TI The RASSCALS: An X-ray and optical study of 260 galaxy groups SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : clusters : general; galaxies : statistics ID SKY REDSHIFT SURVEY; COMPACT-GROUPS; LUMINOSITY FUNCTION; ROSAT OBSERVATIONS; ASTRONOMICAL DATA; POOR CLUSTERS; CD GALAXIES; MASS; REGRESSION; UNIVERSE AB We describe the ROSAT All-Sky Survey-Center for Astrophysics Loose Systems (RASSCALS), the largest X-ray and optical survey of low-mass galaxy groups to date. We draw 260 groups from the combined Center for Astrophysics and Southern Sky Redshift Surveys, covering one-quarter of the sky to a limiting Zwicky magnitude of m(z) = 15.5. We detect 61 groups (23%) as extended X-ray sources. The statistical completeness of the sample allows us to make the first measurement of the X-ray selection function of groups, along with a clean determination of their fundamental scaling laws. We find robust evidence of similarity breaking in the relationship between the X-ray luminosity and velocity dispersion. Groups with sigma(p) < 340 km s(-1) are overluminous by several orders of magnitude compared to the familiar L-x proportional to sigma(4) law for higher velocity dispersion systems. An understanding of this break depends on the detailed structure of groups with small velocity dispersions sigma(p) < 150 km s(-1). After accounting for selection effects, we conclude that only 40% of the optical groups are extended X-ray sources. The remaining 60% are either accidental superpositions or systems devoid of X-ray emitting gas. Combining our results with group statistics from N-body simulations, we find that the fraction of real, bound systems in our objectively selected optical catalog is between 40%-80%. The X-ray detections have a median membership of nine galaxies, a median recession velocity ct = 7250 km s(-1), a median projected velocity dispersion sigma(p) = 400 km s(-1) and a median X-ray luminosity L-X = 3 x 10(42) h(100)(-2) ergs s(-1), where the Hubble constant is H-0 = 100 h(100) km s(-1) Mpc(-1). We include a catalog of these properties, or the appropriate upper limits, for all 260 groups. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Osservatorio Astron Trieste, I-34131 Trieste, Italy. RP Mahdavi, A (reprint author), Harvard Smithsonian Ctr Astrophys, MS 10,60 Garden St, Cambridge, MA 02138 USA. NR 55 TC 74 Z9 75 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2000 VL 534 IS 1 BP 114 EP 132 DI 10.1086/308740 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316TC UT WOS:000087183300012 ER PT J AU Knapp, GR Crosas, M Young, K Ivezic, Z AF Knapp, GR Crosas, M Young, K Ivezic, Z TI Atomic carbon in the envelopes of carbon-rich post-asymptotic giant branch stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; stars : abundances; stars : AGB and post-AGB; stars : evolution ID CORONAE-BOREALIS STARS; HIGH-RESOLUTION SPECTROSCOPY; MULTIPLE MOLECULAR WINDS; RED-RECTANGLE NEBULA; MASS-LOSS RATES; CIRCUMSTELLAR ENVELOPES; EVOLVED STARS; PLANETARY-NEBULAE; ALPHA-ORIONIS; PROTOPLANETARY NEBULAE AB Atomic carbon has been detected in the envelopes of three carbon-rich evolved stars: HD 44179 (=AFGL 915, the "Red Rectangle"), HD 56126, and, tentatively, the carbon star V Hya. This brings to seven the number of evolved star envelopes in which C has been detected. Upper limits were found for several other stars, including R CrB. C I was not detected in several oxygen-rich post-asymptotic giant branch (AGB) stars (OH 231.8 + 4.2, for example), although it is detected in their carbon-rich analogs. Two trends are evident in the data. First, circumstellar envelopes with detectable C I are overwhelmingly carbon-rich, suggesting that much of the C I is produced by the dissociation of molecules other than CO. Second, the more evolved the envelope away from the AGE, the higher the C I/CO ratio. The oxygen-rich supergiant star alpha Ori remains the only oxygen-rich star with a wind containing detectable C r. These data suggest an evolutionary sequence for the C I/CO ratio in cool circumstellar envelopes. This ratio is small (a few percent) while the star is on the AGE, and the C I is located in the outer envelope and produced by photodissociation. The ratio increases to about 0.5 as the star evolves away from the AGE because of the dissociation of CO and other carbon-bearing molecules by shocks caused by the fast winds which appear at the end of evolution on the AGE. Finally, the ratio becomes >>1 as the central star becomes hot enough to photodissociate CO. C1 Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. RP Knapp, GR (reprint author), Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. NR 65 TC 25 Z9 25 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2000 VL 534 IS 1 BP 324 EP 334 DI 10.1086/308731 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316TC UT WOS:000087183300031 ER PT J AU Chatterjee, P Hernquist, L Narayan, R AF Chatterjee, P Hernquist, L Narayan, R TI An accretion model for anomalous X-ray pulsars SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; pulsars : general; stars : neutron; X-rays : stars ID ADVECTION-DOMINATED ACCRETION; MAGNETIZED NEUTRON-STARS; SOFT GAMMA-REPEATERS; RX J0720.4-3125; BLACK-HOLE; QUIESCENCE; EVOLUTION; SUPERNOVA; BURSTS; TRANSIENTS AB We present a model for the anomalous X-ray pulsars (AXPs) in which the emission is powered by accretion from a fossil disk, established from matter falling back onto the neutron star following its birth. The time-dependent accretion drives the neutron star toward a "tracking" solution in which the rotation period of the star increases slowly, in tandem with the declining accretion rate. For appropriate choices of disk mass, neutron star magnetic field strength, and initial spin period, we demonstrate that a rapidly rotating neutron star can be spun down to periods characteristic of AXPs on timescales comparable to the estimated ages of these sources. In other cases, accretion onto the neutron star switches off after a short time and the star becomes an ordinary radio pulsar. Thus, in our picture, radio pulsars and AXPs are drawn from the same underlying population, in contrast to the situation in models involving neutron stars with ultrastrong magnetic fields, which require a new population of stars with very different properties. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Chatterjee, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 52 TC 232 Z9 238 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2000 VL 534 IS 1 BP 373 EP 379 DI 10.1086/308748 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316TC UT WOS:000087183300036 ER PT J AU Catanese, M Sambruna, RM AF Catanese, M Sambruna, RM TI A rapid X-ray flare from Markarian 501 SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL Lacertae objects : individual (Markarian 501); galaxies : jets; X-rays : galaxies ID ENERGY GAMMA-RAYS; TIMING EXPLORER; VARIABILITY; BLAZARS; PERFORMANCE; TELESCOPE AB We present X-ray observations of the BL Lacertae object Mrk 501 that were taken with the Rossi X-Ray Timing Explorer in 1998 May as part of a multiwavelength campaign. The X-ray light curve shows a very rapid flare in which the 2-10 keV flux increased by similar to 60% in less than 200 s. This rapid rise is followed by a drop-off in the 2-10 keV flux of similar to 40% in less than 600 s. The 10-15 keV variation in this flare is roughly a factor of 2 on similar timescales. During the rise of the flare, the 3-15 keV spectral index hardened from 2.02 +/- 0.03 to 1.87 +/- 0.04, where it remained during the decay of the flare. This is the fastest variation ever seen in X-rays from Mrk 501 and among the fastest seen at any wavelength for this object. The shift in the energy at which the spectral power peaks (from less than or equal to 3 keV before the flare to greater than or similar to 30 keV during the flare) is also among the most rapid shifts seen from this object. This flare occurs during an emission state (2-10 keV flux approximate to 1.2 x 10(-10) ergs cm(-2) s(-1)) that is approximately 25% of the peak flux observed in 1997 April from this object but that is still high compared to its historical average X-ray flux. The variations in the hardness ratio are consistent with the low-energy variations leading those at high energies during the development and decay of the flare. This pattern is rare among high-frequency peaked BL Lac objects like Mrk 501, but has been seen recently in two other TeV-emitting BL Lac objects, Mrk 421 and PKS 2155-304. The hard lag is consistent with a Bare dominated by the acceleration timescale for a simple relativistic shock model of flaring. C1 Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, State Coll, PA 16802 USA. RP Catanese, M (reprint author), Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, POB 97, Amado, AZ 85645 USA. NR 26 TC 34 Z9 34 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2000 VL 534 IS 1 BP L39 EP L42 DI 10.1086/312637 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316TD UT WOS:000087183400010 ER PT J AU Gaetz, TJ Butt, YM Edgar, RJ Eriksen, KA Plucinsky, PP Schlegel, EM Smith, RK AF Gaetz, TJ Butt, YM Edgar, RJ Eriksen, KA Plucinsky, PP Schlegel, EM Smith, RK TI Chandra X-ray Observatory arcsecond imaging of the young, oxygen-rich supernova remnant 1E 0102.2-7219 SO ASTROPHYSICAL JOURNAL LA English DT Article DE Magellanic Clouds; shock waves; supernova remnants; X-rays : ISM ID SMALL MAGELLANIC CLOUD; AXAF AB We present observations of the young, oxygen-rich supernova remnant 1E 0102.2-7219 taken by the Chandra X-Ray Observatory during its orbital activation and checkout phase. The boundary of the blast-wave shock is clearly seen for the first time, allowing the diameter of the remnant and the mean blast-wave velocity to be determined accurately. The prominent X-ray bright ring of material may be the result of the reverse shock encountering ejecta; the radial variation of O VII versus O VIII emission indicates an ionizing shock propagating inward, possibly through a strong density gradient in the ejecta. We compare the X-ray emission with Australia Telescope Compact Array 6 cm radio observations (Amy & Ball) and with archival Hubble Space Telescope [O III] observations. The ring of radio emission is predominantly inward of the outer blast wave, which is consistent with an interpretation of synchrotron radiation originating behind the blast wave but outward of the bright X-ray ring of emission. Many (but not all) of the prominent optical filaments are seen to correspond to X-ray bright regions. We obtain an upper limit of similar to 9 x 10(33) ergs s(-1) (3 sigma) on any potential pulsar X-ray emission from the central region. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gaetz, TJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 13 TC 53 Z9 53 U1 1 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2000 VL 534 IS 1 BP L47 EP L50 DI 10.1086/312640 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316TD UT WOS:000087183400012 ER PT J AU Saar, SH Fischer, D AF Saar, SH Fischer, D TI Correcting radial velocities for long-term magnetic activity variations SO ASTROPHYSICAL JOURNAL LA English DT Article DE convection; planetary systems; stars : activity; stars : late-type; stars : spots; techniques : radial velocities ID SOLAR-TYPE STARS; SUN-LIKE STARS; COOL STARS; LINE ASYMMETRIES; ROTATION; GRANULATION; VARIABILITY; EMISSION; HISTORY AB We study stars in the Lick planetary survey for correlations between simultaneous measurements of high-precision radial velocities v(r) and magnetic activity (as measured in an S-IR emission index from Ca II lambda 8662). We find significant correlations in approximate to 30% of the stars. After removing linear trends between S-IR and v(r), we find that the dispersion in v(r) in these stars is decreased by an average of 17%, or approximate to 45% of the dispersion above the measurement noise. F stars and less active stars with variable Ca II H and K lines are the most successfully corrected. The magnitude of the slope of the S-IR versus v(r) relations increases proportional to v sin i and (excepting M dwarfs) tends to decrease with decreasing T-eff. We argue that the main cause of these effects is modification of the mean line bisector shape brought on by long-term, magnetic activity-induced changes in the surface brightness and convective patterns. The correlations can be used to partially correct v, data for the effects of long-term activity variations, potentially permitting study of planets around some (higher mass) younger stars and planets producing smaller stellar reflex velocities. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Saar, SH (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 37 TC 42 Z9 42 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2000 VL 534 IS 1 BP L105 EP L108 DI 10.1086/312648 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316TD UT WOS:000087183400026 ER PT J AU Wilner, DJ Ho, PTP Kastner, JH Rodriguez, LF AF Wilner, DJ Ho, PTP Kastner, JH Rodriguez, LF TI VLA imaging of the disk surrounding the nearby young star TW Hydrae SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; circumstellar matter; radio continuum : stars; stars : formation; stars : individual (TW Hydrae) ID SPECTRAL ENERGY-DISTRIBUTIONS; TAURI STARS; STELLAR OBJECTS; CIRCUMSTELLAR DISKS; HL TAURI; X-RAY; ACCRETION; EVOLUTION; CONTINUUM; EMISSION AB The TW Hydrae system is perhaps the closest analog to the early solar nebula. We have used the Very Large Array to image TW Hya at wavelengths of 7 mm and 3.6 cm with resolutions of 0." 1 (similar to 5 AU) and 1." 10 (similar to 50 AU), respectively. The 7 mm emission is extended and appears dominated by a dusty disk of radius greater than 50 AU surrounding the star. The 3.6 cm emission is unresolved and likely arises from an ionized wind or gyrosynchrotron activity. The dust spectrum and spatially resolved 7 mm images of the TW Hya disk are fitted by a simple model with temperature and surface density described by radial power laws, T(r) proportional to r(-0.5) and Sigma(r) proportional to r(-1). These properties are consistent with an irradiated gaseous accretion disk of mass similar to 0.03 M-circle dot with an accretion rate similar to 10(-8) M-circle dot yr(-1) and viscosity parameter alpha = 0.01. The estimates of mass and mass accretion rates are uncertain since the gas-to-dust ratio in the TW Hya disk may have evolved from the standard interstellar value. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Rochester Inst Technol, Chester F Carlson Ctr Imaging Sci, Rochester, NY 14623 USA. Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico. RP Wilner, DJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 32 TC 123 Z9 123 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2000 VL 534 IS 1 BP L101 EP L104 DI 10.1086/312642 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316TD UT WOS:000087183400025 ER PT J AU Marra, PP AF Marra, PP TI The role of behavioral dominance in structuring patterns of habitat occupancy in a migrant bird during the nonbreeding season SO BEHAVIORAL ECOLOGY LA English DT Article DE American redstarts; behavioral dominance; habitat specialization; migratory birds; nonbreeding season; removal and playback experiments; Setophaga ruticilla; sexual habitat segregation ID DARK-EYED JUNCOS; AMERICAN REDSTARTS; WINTER SURVIVAL; FORAGING BEHAVIOR; MIGRATORY BIRD; WILLOW TITS; SEGREGATION; CORTICOSTERONE; POPULATION; WARBLERS AB Several species of territorial migratory birds exhibit sexual habitat segregation on their wintering grounds, with some habitats containing mostly males and others mostly females. The objective of this study was to determine if in the American redstart (Setophaga ruticilla) in Jamaica habitat segregation is due to social mechanisms or due to sex-specific habitat specialization. I used habitat-specific patterns of arrival by young males and females, observations of territorial displacements, removal experiments. and simulations of territorial intrusions to differentiate between these two mechanisms. Redstarts were studied in two habitat types, a male-biased mangrove forest and a female-biased scrub habitat. In autumn, male and female hatch-year redstarts initially settled in equal numbers in each habitat, and segregation of the sexes occurred gradually and mostly later in the arrival period. This shift corresponded with an increase in density of older birds and an increase in territorial displacements. Removal experiments showed that vacancies in male-biased habitat were filled more rapidly and with greater frequency than those in female-biased habitat and that vacated male territories in mangrove were replaced more often by females than by males. Simulations of territorial intrusions and analyses of body size indicated that levels of aggression and body size of both males and females were greater in mangrove habitat, suggesting that these factors may be important in determining the outcomes of dominance interactions. I conclude that patterns of sexual habitat segregation in redstarts are structured by the dominance behavior of older and more dominant individuals, and these are mostly males. C1 Dartmouth Coll, Dept Biol Sci, Hanover, NH 03755 USA. RP Marra, PP (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. RI Piper, Walter/B-7908-2009 NR 70 TC 149 Z9 150 U1 2 U2 31 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 1045-2249 J9 BEHAV ECOL JI Behav. Ecol. PD MAY-JUN PY 2000 VL 11 IS 3 BP 299 EP 308 DI 10.1093/beheco/11.3.299 PG 10 WC Behavioral Sciences; Biology; Ecology; Zoology SC Behavioral Sciences; Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Zoology GA 337VN UT WOS:000088382500009 ER PT J AU Pope, DS AF Pope, DS TI Testing function of fiddler crab claw waving by manipulating social context SO BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY LA English DT Article DE fiddler crabs; territorial signal; social context ID UCA-PUGILATOR BOSC; TERRITORIAL DEFENSE; SONG REPERTOIRE; BEHAVIOR; ANNULIPES; EVOLUTION; DISPLAY; TANGERI; LIZARD AB Many territorial advertisement signals are thought to be dual-function signals, directed to both rival male and receptive female conspecifics. However, few studies have tested this assumption by examining whether in fact both sexes are likely to elicit signaling behavior from territorial males. In this study, I experimentally manipulated the social context of male sand fiddler crabs (Uca pugilator) to investigate the effect of different audiences on the performance of the claw-waving display, a territorial signal that is often presumed to be directed to both males and females. To test whether males perform this signal to both audiences, I measured the frequency of waving behavior by focal males when housed in field enclosures alone, with only males, with only females, or with both males and females. Focal males waved at a low frequency when alone, and the presence of males had no effect on their level of waving. However, in the presence of females, focal males showed a significantly higher level of waving, whether or not males were also present. In addition, there was no association between fighting and waving behavior. This experiment provides evidence that from the perspective of the signaling male, the claw-waving display of U. pugilator is not a dual-function signal but rather is primarily directed to receptive females. C1 Duke Univ, Dept Zool, Durham, NC 27708 USA. RP Pope, DS (reprint author), Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. EM poped@naos.si.edu NR 44 TC 57 Z9 59 U1 2 U2 22 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0340-5443 J9 BEHAV ECOL SOCIOBIOL JI Behav. Ecol. Sociobiol. PD MAY PY 2000 VL 47 IS 6 BP 432 EP 437 DI 10.1007/s002650050687 PG 6 WC Behavioral Sciences; Ecology; Zoology SC Behavioral Sciences; Environmental Sciences & Ecology; Zoology GA 322WE UT WOS:000087531600009 ER PT J AU Lee, KY Fisher, TR Jordan, TE Correll, DL Weller, DE AF Lee, KY Fisher, TR Jordan, TE Correll, DL Weller, DE TI Modeling the hydrochemistry of the Choptank River Basin using GWLF and Arc/Info: 1. Model calibration and validation SO BIOGEOCHEMISTRY LA English DT Article DE GIS; GWLF; nonpoint source pollution; nutrient; watershed modeling ID CHESAPEAKE BAY ANOXIA; DELMARVA PENINSULA; NITRATE CONCENTRATIONS; HYDROLOGIC LANDSCAPES; LAND-USE; NUTRIENTS; FLOW; PHYTOPLANKTON; NITROGEN; EUTROPHICATION AB We modeled nutrient export in the Choptank River Basin on the coastal plain of the Chesapeake drainage, using a modified version of a lumped-parameter, hydrochemical model (GWLF). Calibration was performed using long-term (WY1980-WY1990) hydrochemistry data from a gauged site. The calibrated model reproduced water yields, TN, and TP export with cumulative errors of < 1% over the 11-year calibration period and with annual RMS errors of 10-50%. Model validation was done with independent measurements at the same gauged site (WY1991 to WY1996) and at another nearby independently gauged site (WY1991 to WY1995). Local adjustment of the groundwater recession coefficient and the dissolved N concentration in agricultural stormflow was essential for successful application at the second site. GWLF appears to be a useful model for estimation of fluxes of water, N and P from ungauged areas with accuracies of 10-50% at annual time scales. C1 Univ Maryland, Horn Point Environm Lab, Ctr Environm Sci, Cambridge, MD 21613 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Lee, KY (reprint author), Univ Maryland, Horn Point Environm Lab, Ctr Environm Sci, POB 775, Cambridge, MD 21613 USA. OI Weller, Donald/0000-0002-7629-5437 NR 50 TC 40 Z9 41 U1 7 U2 15 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-2563 J9 BIOGEOCHEMISTRY JI Biogeochemistry PD MAY PY 2000 VL 49 IS 2 BP 143 EP 173 DI 10.1023/A:1006375530844 PG 31 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 286AZ UT WOS:000085422600003 ER PT J AU Peslier, AH Reisberg, L Ludden, J Francis, D AF Peslier, AH Reisberg, L Ludden, J Francis, D TI Os isotopic systematics in mantle xenoliths; age constraints on the Canadian Cordillera lithosphere SO CHEMICAL GEOLOGY LA English DT Article DE Re-Os; peridotite xenolith; mantle; Canadian Cordillera; Proterozoic; crust ID SPINEL LHERZOLITE XENOLITHS; PLATINUM-GROUP ELEMENTS; COAST PLUTONIC COMPLEX; RE-OS; BRITISH-COLUMBIA; PERIDOTITE XENOLITHS; SM-ND; SUBCONTINENTAL MANTLE; MASS-SPECTROMETRY; SUBDUCTION ZONES AB The Os-187/Os-188 ratios of Iherzolites from eight xenolith suites from the Canadian Cordillera show a correlation with Al2O3 and heavy rare earth elements (HREE). The best interpretation of these correlations appears to be ancient melt depletion followed by a long period of radiogenic ingrowth. The Os-187/Os-188-Lu correlation is used to calculate an Os model age of 1.12 +/- 0.26 Ga for the lithospheric mantle throughout the Canadian Cordillera. This single melting age suggests that the mantle lithosphere now underlying the entire Canadian Cordillera may have formed by melting events closely spaced in rime. This is consistent with seismic evidence of the extension of crustal basement under much of the Canadian Cordillera that is independent of the upper-crustal terranes overlying it. Indeed, this Proterozoic Os model age for the mantle contrasts with the younger formation ages (Nd model ages and U-Pb ages of zircons) of most crustal terranes of the region which are around 0.5 Ga. Early Proterozoic basement is exposed only in southeastern British Columbia and has the same age (1.9 to 2.3 Ga) as the ancestral North American crust, but is older than the Os model age of the mantle lithosphere underlying the Canadian Cordillera. The Canadian Cordilleran mantle is thus probably not a simple extension of the North American cratonic lithosphere beneath the adjacent mobile orogenic belt of the Canadian Cordillera. The difference in age between the formation of the Canadian Cordillera upper-crust and the formation of the underlying mantle suggests that this mantle lithosphere does not represent the mantle roots of the crustal terranes overlying it. Instead, these crustal terranes were thrust onto the mantle lithosphere during Canadian Cordillera orogeny. This contrasts strongly with Archean cratonic zones and Early Proterozoic belts where oldest crustal rocks and mantle may have the same formation age. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Montreal, Montreal, PQ H3C 3J7, Canada. CNRS, CRPG, F-54501 Vandoeuvre Nancy, France. McGill Univ, Montreal, PQ H3A 2A7, Canada. RP Peslier, AH (reprint author), Smithsonian Inst, Museum Nat Hist, Dept Mineral Sci, NHB-119, Washington, DC 20560 USA. RI Peslier, Anne/F-3956-2010 NR 82 TC 69 Z9 70 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD MAY 1 PY 2000 VL 166 IS 1-2 BP 85 EP 101 DI 10.1016/S0009-2541(99)00187-4 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 296BY UT WOS:000086004200006 ER PT J AU Grosholz, ED Ruiz, GM Dean, CA Shirley, KA Maron, JL Connors, PG AF Grosholz, ED Ruiz, GM Dean, CA Shirley, KA Maron, JL Connors, PG TI The impacts of a nonindigenous marine predator in a California bay SO ECOLOGY LA English DT Review DE Carcinus maenas; European green crab; food webs; Hemigrapsus oregonesis; indirect effects; nonindigenous species; Nutricola spp.; predation; shorebirds; trophic levels ID CRAB CARCINUS-MAENAS; SAN-FRANCISCO BAY; SOFT-BOTTOM COMMUNITIES; EUROPEAN GREEN CRAB; NATIVE MUD SNAILS; FOOD WEBS; BIOLOGICAL INVASIONS; PATH-ANALYSIS; WADDEN SEA; COMPETITIVE DISPLACEMENT AB Coastal marine ecosystems worldwide are being altered rapidly by the invasion of nonindigenous species. Unlike terrestrial and freshwater systems, the impacts of an invading species have never been quantified on multiple trophic levels for a marine food web. We measured the impact of the nonindigenous green crab, Carcinus maenas, on a coastal marine food web in central California and found that this predator exerted strong "top-down" control, significantly reducing the abundances of several of the 20 invertebrate species monitored over a 9-yr period. Densities of native clams, Nutricola tantilla and Nutricola confusa, and native shore crabs, Hemigrapsus oregonensis, showed 5-fold to 10-fold declines within 3 yr of the arrival of green crabs. Field and laboratory experiments indicated that green crab predation caused these declines. We also tested for indirect responses of invertebrates and vertebrates to green crab predation. There were significant increases in the abundances of two polychaete taxa, Lumbrineris sp. and Exogene sp., and tube-building tanaid crustaceans, Leptochelia dubia, most likely due to the removal of cooccurring green crab prey. However, we observed no changes in shorebird abundances (13 species) over a 9-yr period suggesting that green crabs have had no "bottom-up" effect on shorebirds, which subsist on benthic invertebrate prey. We predict that such bottom-up control will occur as the local effects and geographic range of green crabs increase. The 2-yr temporal scale of direct and indirect responses of the invertebrates in this low energy, soft-substrate system was also in agreement with the results of perturbation experiments by others on rocky shores, which showed that most direct and indirect responses also occur within a 2-yr time frame. C1 Univ Calif Davis, Ctr Populat Biol, Davis, CA 95616 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Bodega Marine Lab, Bodega Bay, CA 94923 USA. RP Grosholz, ED (reprint author), Univ Calif Davis, Dept Environm Sci & Policy, 1 Shields Ave, Davis, CA 95616 USA. OI Ruiz, Gregory/0000-0003-2499-441X NR 114 TC 217 Z9 227 U1 6 U2 80 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 0012-9658 J9 ECOLOGY JI Ecology PD MAY PY 2000 VL 81 IS 5 BP 1206 EP 1224 DI 10.1890/0012-9658(2000)081[1206:TIOANM]2.0.CO;2 PG 19 WC Ecology SC Environmental Sciences & Ecology GA 309XQ UT WOS:000086795100003 ER PT J AU Flint, OS AF Flint, OS TI A new species of Leptonema of the Occidentale group (Trichoptera : Hydropsychidae) from Madagascar SO ENTOMOLOGICAL NEWS LA English DT Article AB Leptonema ranomafana new species. a member of the occidentale group, is described from the Ranomafana National Park in Madagascar. Eight species were previously recognized from the island, all belonging to the endemic affine group. The occidentale group had been known from 5 species recorded from Ghana south and east through central Africa to Natal. The Madagascan species agrees closely with its group, but is easily recognized by the structure of the tenth tergum and phallus. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Entomol, Washington, DC 20560 USA. RP Flint, OS (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Entomol, Washington, DC 20560 USA. NR 5 TC 0 Z9 0 U1 1 U2 1 PU AMER ENTOMOL SOC PI PHILADELPHIA PA 1900 BENJ FRANKLIN PARKWAY, PHILADELPHIA, PA 19103-1195 USA SN 0013-872X J9 ENTOMOL NEWS JI Entomol. News PD MAY-JUN PY 2000 VL 111 IS 3 BP 177 EP 180 PG 4 WC Entomology SC Entomology GA 332BE UT WOS:000088052600004 ER PT J AU Thompson, FC AF Thompson, FC TI A new Oriental blera (Diptera : Syrphidae) SO ENTOMOLOGICAL NEWS LA English DT Article AB The only known Blera from the Oriental Region is described and named himalaya (HTO The Natural History Museum, London). C1 Smithsonian Inst, Systemat Entomol Lab, USDA ARS, Washington, DC 20560 USA. RP Thompson, FC (reprint author), Smithsonian Inst, Systemat Entomol Lab, USDA ARS, NHB-168, Washington, DC 20560 USA. NR 3 TC 3 Z9 4 U1 0 U2 0 PU AMER ENTOMOL SOC PI PHILADELPHIA PA 1900 BENJ FRANKLIN PARKWAY, PHILADELPHIA, PA 19103-1195 USA SN 0013-872X J9 ENTOMOL NEWS JI Entomol. News PD MAY-JUN PY 2000 VL 111 IS 3 BP 181 EP 184 PG 4 WC Entomology SC Entomology GA 332BE UT WOS:000088052600005 ER PT J AU Macintyre, IG Bayer, FM Logan, MAV Skinner, HCW AF Macintyre, IG Bayer, FM Logan, MAV Skinner, HCW TI Possible vestige of early phosphatic biomineralization in gorgonian octocorals (Coelenterata) SO GEOLOGY LA English DT Article DE octocorals; biomineralization; skeletal carbonate hydroxylapatite; Gorgoniidae AB Skeletal carbonate hydroxylapatite, heretofore unknown in modern coelenterates, has been found in the axes and holdfasts of the gorgonian octocoral family Gorgoniidae. This carbonate apatite is a distinctive feature of this family of octocorals and may indicate a previous history of phosphatic skeletal mineralization within this phylum. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Mineral Sci, Washington, DC 20560 USA. Yale Univ, Dept Geol & Geophys, New Haven, CT 06520 USA. RP Macintyre, IG (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. NR 28 TC 21 Z9 21 U1 1 U2 4 PU GEOLOGICAL SOC AMER, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD MAY PY 2000 VL 28 IS 5 BP 455 EP 458 PG 4 WC Geology SC Geology GA 308BU UT WOS:000086689300018 ER PT J AU Stone, G Besser, D Lewis, LE AF Stone, G Besser, D Lewis, LE TI Recall, liking, and creativity in TV commercials: A new approach SO JOURNAL OF ADVERTISING RESEARCH LA English DT Article ID AD; ATTITUDE; IMPACT; RECOGNITION; MEMORY; REDUX AB Three advertising effectiveness dimensions were linked in a local random telephone survey asking respondents' most disliked or liked commercial. The survey included describing the commercials, brand preference, television viewing hours, and demographics. Seniors in advertising judged the advertisement's creativity. Among many findings related to past research was the suggestion that people "carry a set" of liked and disliked commercials. The study's major contribution may be its novel way of identifying memorable advertisements and assessing creativity. C1 So Illinois Univ, Coll Mass Commun & Media Arts, Carbondale, IL 62901 USA. Smithsonian Inst, Washington, DC 20560 USA. RP Stone, G (reprint author), So Illinois Univ, Coll Mass Commun & Media Arts, Carbondale, IL 62901 USA. NR 54 TC 24 Z9 24 U1 5 U2 24 PU ADVERTISING RES FOUNDATION PI NEW YORK PA 641 LEXINGTON AVE, NEW YORK, NY 10022 USA SN 0021-8499 J9 J ADVERTISING RES JI J. Advert. Res. PD MAY-JUN PY 2000 VL 40 IS 3 BP 7 EP 18 PG 12 WC Business; Communication SC Business & Economics; Communication GA 336GA UT WOS:000088292500002 ER PT J AU Cadaval, O AF Cadaval, O TI 'Show trial' or 'truth and reconciliation'? A response (Culture, representation) SO JOURNAL OF FOLKLORE RESEARCH LA English DT Article ID POLITICS AB This essay reflects on the growing existence of "collaborative ethnography" as a research goal and method. "Show Trial" and "Truth and Reconciliation" serve as metaphors for understanding the differences that Pat Mullen and Jesse Truvillion bring to their discussions of a joint project. As Cadaval examines entwined issues of reflexivity and "native" perspectiveand ultimately the politics of scholarship that concern many who struggle to find equitable modes of research and representationshe also reflects on a legacy of socially engaged scholars, such as Don Americo Paredes and his dialogic conceptualization of the ethnographic encounter. Cadaval argues that this conceptualization can and should be reflected in both field methodology and public presentations. C1 Smithsonian Inst, Ctr Folklife & Cultural Heritage, Washington, DC 20560 USA. RP Cadaval, O (reprint author), Smithsonian Inst, Ctr Folklife & Cultural Heritage, Washington, DC 20560 USA. NR 20 TC 3 Z9 3 U1 0 U2 0 PU INDIANA UNIV PI BLOOMINGTON PA FOLKLORE INST 504 NORTH FESS ST, BLOOMINGTON, IN 47405 USA SN 0737-7037 J9 J FOLKLORE RES JI J. Folk. Res. PD MAY-DEC PY 2000 VL 37 IS 2-3 BP 185 EP 195 PG 11 WC Folklore SC Arts & Humanities - Other Topics GA 397KA UT WOS:000166693800007 ER PT J AU Stafford, BJ Szalay, FS AF Stafford, BJ Szalay, FS TI Craniodental functional morphology and taxonomy of dermopterans SO JOURNAL OF MAMMALOGY LA English DT Article DE Colugo; Cynocephalidae; Cynocephalus volans; flying lemur; Galcopterus variegatus; kagwang; Microsyopidae; Mixodectidae; Plagiomenidae ID SOUTHEAST-ASIA; MAMMALIA; EOCENE; PLESIADAPIFORMES; BIOGEOGRAPHY; AFFINITIES; EVOLUTION; ISLAND; GENUS; BATS AB Craniodental form and function were evaluated in the 2 extant, parapatric species of dermopterans (Dermoptera: Cynocephalidae). The level of morphological distinction between the 2 taxa was such that were they known as fossils; most taxonomists would not contest their genus-level distinction as indicative of adaptive differentiation. In fact, these taxa exemplify the widely employed but implicit morphological distance-based standards used for delineating mammalian genera in the paleontological literature. Appropriate names for these 2 taxa are Cynocephalus volans for the Philippine flying lemur and Galeopterus variegatus for the heterogeneous populations of the Sundaic flying lemurs. Cynocephalus probably has a hypertrophied version of the ancestral cynocephalid molar complex and modified incisor and canine morphology. The hypertrophied metaconules of cynocephalids occlude with an expanded paracristid and a cusplike shelf, the distocuspid. Cynocephalus also has a broader rostrum, a greater degree of postorbital constriction, and enhanced ectocranial ridges associated with a more robust masticatory musculature than Galeopterus. Cynocephalus appears adapted to a diet that requires a greater degree of shearing by the anterior dentition and crushing by the molariform dentition. These anterior shearing teeth (13, C1, P3, c1, p3) are larger and more bladelike than those of Galeopterus, and the bite force is more anteriorly directed. Angle of the mandible is ventrally expanded in Cynocephalus, facilitating enhanced chewing force for the post canine dentition while maintaining orientation of the temporalis muscle. Dwarfed forms of Galeopterus are found on many of the smaller islands of the Sunda Shelf and in central Laos, They are not morphologically distinguishable from larger members of this species, other than in size, and do not warrant specific distinction. However, it may be desirable to designate 4 subspecies of G. variegatus: G. v. variegatus from Java, G. v. temminckii from Sumatra, G. v. borneanus from Borneo, and G. v. peninsulae from the Malay Peninsula and mainland Southeast Asia. Separate species rank for each of the dwarfed populations should not be recognized. Phylogenetic relationships of Dermoptera are discussed in light of the morphological differences of the 2 genera. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Div Mammals, Washington, DC 20560 USA. CUNY Hunter Coll, Dept Anthropol, New York, NY 10021 USA. RP Stafford, BJ (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Div Mammals, NHB 390, Washington, DC 20560 USA. EM stafford.brian@nmnh.si.edu NR 92 TC 21 Z9 27 U1 1 U2 15 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 0022-2372 EI 1545-1542 J9 J MAMMAL JI J. Mammal. PD MAY PY 2000 VL 81 IS 2 BP 360 EP 385 DI 10.1644/1545-1542(2000)081<0360:CFMATO>2.0.CO;2 PG 26 WC Zoology SC Zoology GA 316ET UT WOS:000087155200005 ER PT J AU White, PJ Ralls, K Siniff, DB AF White, PJ Ralls, K Siniff, DB TI Nocturnal encounters between kit foxes SO JOURNAL OF MAMMALOGY LA English DT Article DE association; behavior; California; kit fox; Vulpes macrotis ID MORTALITY; EVOLUTION; PATTERNS; WOLVES AB Kit foxes (Vulpes macrotis) are nocturnal, monogamous, and territorial. We used telemetry to monitor nocturnal interactions of pair members with each other and neighboring foxes in central California during 1989-1991. Observed distances between mated foxes consistently were closer than expected by chance. This positive association probably resulted from a tendency for foxes to move around common den or foraging sites; mates did not exhibit concordant movement patterns. Nocturnal encounters probably are not necessary to maintain pair bonds because mates regularly share dens during the day throughout the year. Encounters may be more important during pair formation because members of recently formed pairs encountered each other more frequently (>16% of locations) than did established pairs (<13% of locations). Observed distances between neighboring foxes were not consistently closer or further apart than expected by chance, and encounters were rare (<2% of locations). Hence, direct interactions between neighboring foxes may be relatively unimportant for maintaining established territories. However, 2 male mated kit foxes trespassed into neighboring territories during the breeding season, probably in search of extrapair copulations. C1 US Fish & Wildlife Serv, Carlsbad, CA 92008 USA. Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. Univ Minnesota, Dept Ecol Evolut & Behav, St Paul, MN 55108 USA. RP White, PJ (reprint author), US Fish & Wildlife Serv, Carlsbad, CA 92008 USA. EM patrick_white@fws.gov NR 23 TC 15 Z9 15 U1 1 U2 4 PU ALLIANCE COMMUNICATIONS GROUP DIVISION ALLEN PRESS PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 USA SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD MAY PY 2000 VL 81 IS 2 BP 456 EP 461 DI 10.1644/1545-1542(2000)081<0456:NEBKF>2.0.CO;2 PG 6 WC Zoology SC Zoology GA 316ET UT WOS:000087155200013 ER PT J AU Thiel, M AF Thiel, M TI Juvenile Sphaeroma quadridentatum invading female-offspring groups of Sphaeroma terebrans SO JOURNAL OF NATURAL HISTORY LA English DT Article DE reproduction; extended parental care; Isopoda; Peracarida; burrow invasion ID EXTENDED PARENTAL CARE; PARACERCEIS-SCULPTA; CRUSTACEA; ISOPODA AB Female isopods Sphaeroma terebrans Bate 1866 are known to host their offspring in family burrows in aerial roots of the red mangrove Rhizophora mangle. During a study on the reproductive biology of S. terebrans in the Indian River Lagoon, Florida, USA, juvenile S. quadridentatum were found in family burrows of S. terebrans. Between September 1997 and August 1998, each month at least one female S. terebrans was found with juvenile S. quadridentatum in its burrow. The percentage of S. terebrans family burrows that contained juvenile S. quadridentatum was high during fall 1997, decreased during the winter, and reached high values again in late spring/early summer 1998, corresponding with the percentage of parental female S. terebrans (i.e. hosting their own juveniles). Most juvenile S. quadridentatum were found with parental female S. terebrans, but a few were also found with reproductive females that were not hosting their own offspring. Non-reproductive S. terebrans(single males, subadults, non-reproductive females) were never found with S. quadridentatum in their burrows. The numbers of S. quadridentatum found in burrows of S. terebrans ranged between one and eight individuals per burrow. No significant correlation between the number of juvenile S. quadridentatum and the numbers of juvenile S. terebrans in a Family burrow existed. However, burrows with high numbers of juvenile S. quadridentatum often contained relatively few juvenile S. terebrans. The majority of juvenile S. quadridentatum found in family burrows of S. terebrans were smaller than the juvenile S. terebrans that were cared for by their mothers. The results indicate that the presence of S. quadridentatum in S. terebrans family burrows may negatively affect the duration of extended parental care in S. terebrans. It is not known why parental female S. terebrans are not able to discriminate against juvenile S. quadridentatum. Possibly, the fact that the two species are closely related facilitates S. quadridentatum sneaking into S. terebrans family burrows. C1 Smithsonian Marine Stn, Ft Pierce, FL 34946 USA. RP Thiel, M (reprint author), Univ Catolica Norte, Fac Ciencias Mar, Larrondo 1281,Campus Guayacan, Coquimbo, Chile. NR 34 TC 8 Z9 8 U1 0 U2 7 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0022-2933 J9 J NAT HIST JI J. Nat. Hist. PD MAY PY 2000 VL 34 IS 5 BP 737 EP 745 DI 10.1080/002229300299381 PG 9 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 310TK UT WOS:000086843300007 ER PT J AU Plasman, V Braekman, JC Daloze, D Luhmer, M Windsor, D Pasteels, JM AF Plasman, V Braekman, JC Daloze, D Luhmer, M Windsor, D Pasteels, JM TI Triterpene saponins in the defensive secretion of a chrysomelid beetle, Platyphora ligata SO JOURNAL OF NATURAL PRODUCTS LA English DT Article ID CARDIAC-GLYCOSIDES; BIOSYNTHESIS; LARVAE AB The secretion of the defensive glands of adults of the chrysomelid beetle Platyphora ligata from Panama has been shown to contain, besides chlorogenic acid (1) and a mixture of phosphatidylcholines, two new oleanane triterpene saponins, named ligatosides A and B. Their structures were established as 3-O-beta-D-glucuronopyranosyl-16 alpha,23-dihydroxyoleanolic acid-28-O-2-(3,4-dimethoxybenzoyl)-beta-D-glucopyranoside (2) and 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-16 alpha,23-dihydroxyoleanic acid-28-O-2-(3,4-dimethoxybenzoyl)-beta-D-glucopyranoside (3), respectively, by a combination of extensive 1D and 2D NMR methods (COSY, HMQC, HMBC, and TOCSY) and FABMS. This is the first report of triterpene saponins in the defensive secretion of an insect. C1 Dept Organ Chem, Bioorgan Chem Lab, Brussels, Belgium. Fac Sci Appl, Organ Chem Lab, Brussels, Belgium. Free Univ Brussels, Lab Cellular & Anim Biol, B-1050 Brussels, Belgium. Smithsonian Trop Res Inst, Balboa, Panama. RP Braekman, JC (reprint author), Dept Organ Chem, Bioorgan Chem Lab, CP 160-07, Brussels, Belgium. NR 20 TC 19 Z9 19 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0163-3864 J9 J NAT PROD JI J. Nat. Prod. PD MAY PY 2000 VL 63 IS 5 BP 646 EP 649 DI 10.1021/np990406t PG 4 WC Plant Sciences; Chemistry, Medicinal; Pharmacology & Pharmacy SC Plant Sciences; Pharmacology & Pharmacy GA 318CT UT WOS:000087266900014 PM 10843577 ER PT J AU Sakai, S AF Sakai, S TI Reproductive phenology of gingers in a lowland mixed dipterocarp forest in Borneo SO JOURNAL OF TROPICAL ECOLOGY LA English DT Article DE Costaceae; dipterocarp forest; reproductive phenology; pollination; Sarawak; tropical forest; understorey; Zingiberaceae ID ASEASONAL TROPICS; COSTA-RICA; HUMMINGBIRD POLLINATION; FLOWERING PHENOLOGY; DRY FORESTS; COMPETITION; WET; SARAWAK; SHRUB; TREES AB Reproductive phenology of 117 individuals from a total of 20 ginger species (Costaceae and Zingiberaceae) was monitored for up to 21 mo in a lowland mixed dipterocarp forest in the Lambir Hills National Park, Sarawak. Of these 20 species of iteroparous perennials, pollinated by either spiderhunters (Nectariniidae), medium-sized Amegilla bees (Anthophoridae), or small halictid bees (Halictidae), many reproduced more than once a year, or flowered continuously with short interruptions. Significant hut weak synchronization in flowering events among conspecific individuals was detected for only two species out of the five examined (Etlingera aff. metriocheilos and Amomum somniculosum). The low synchronization within the population, the overlapping flowering among species sharing common pollinators, and the high flowering frequency for each species, contrast markedly with the reproductive phenology of hummingbird-pollinated and large bee-pollinated plants of related tars in the Neotropics. Although the plants studied do not include all members of each pollination guild, at least one species within a guild was flowering at any time except in the spiderhunter-pollinated guild. Some bee-pollinated gingers may serve as keystone species for survival of the traplining bees living on floral nectar and pollen. C1 Kyoto Univ, Ctr Ecol Res, Sakyo, Olsu 5202113, Japan. RP Sakai, S (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 35 TC 14 Z9 21 U1 4 U2 9 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0266-4674 J9 J TROP ECOL JI J. Trop. Ecol. PD MAY PY 2000 VL 16 BP 337 EP 354 DI 10.1017/S0266467400001449 PN 3 PG 18 WC Ecology SC Environmental Sciences & Ecology GA 347TL UT WOS:000088945200002 ER PT J AU Davis, C Keane, B Swanson, BJ Loew, S Waser, PM Strobeck, C Fleischer, RC AF Davis, C Keane, B Swanson, BJ Loew, S Waser, PM Strobeck, C Fleischer, RC TI Characterization of microsatellite loci in bannertailed and giant kangaroo rats, Dipodomys spectabilis and Dipodomys ingens SO MOLECULAR ECOLOGY LA English DT Article DE Dipodomys; Heteromyidae; kangaroo rats; microsatellites; pocket mice C1 Univ Cincinnati, Dept Biol Sci, Cincinnati, OH 45221 USA. Univ Alberta, Dept Biol Sci, Edmonton, AB T6G 2E9, Canada. Purdue Univ, Dept Biol Sci, W Lafayette, IN 47907 USA. Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. RP Keane, B (reprint author), Univ Cincinnati, Dept Biol Sci, Cincinnati, OH 45221 USA. RI Strobeck, Curtis/E-9998-2011; Strobeck, Curtis/A-3762-2014; Davis, Corey/I-4058-2014 OI Strobeck, Curtis/0000-0002-6171-3130; NR 7 TC 11 Z9 11 U1 0 U2 10 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0962-1083 J9 MOL ECOL JI Mol. Ecol. PD MAY PY 2000 VL 9 IS 5 BP 642 EP 644 DI 10.1046/j.1365-294x.2000.00882-8.x PG 3 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 312BG UT WOS:000086923000019 PM 10792713 ER PT J AU Anderson, FE AF Anderson, FE TI Phylogeny and historical biogeography of the loliginid squids (Mollusca : Cephalopoda) based on mitochondrial DNA sequence data SO MOLECULAR PHYLOGENETICS AND EVOLUTION LA English DT Article DE Loliginidae; molecular systematics; maximum likelihood; squids; phylogeny ID COLEOID CEPHALOPODS; 16S RDNA; LIKELIHOOD; INCONGRUENCE; GENE; CTENOPTERYX; EVOLUTION; MYOPSIDA; TESTS AB The cephalopod taxon Loliginidae (Cephalopoda: Myopsida) is a species-rich group of tropical and temperate shallow-water squids, many of which are commercial, fisheries objects and neurophysiological research organisms. The worldwide distribution of these squids could make Loliginidae a useful case study in shallow-water marine biogeography, but the phylogeny of the group is unknown. To clarify loliginid phylogeny, regions of two mitochondrial genes (the 16S rRNA and the cytochrome c oxidase subunit I genes) were sequenced for members of 19 loliginid species and several outgroups, Maximum-parsimony and maximum-likelihood analyses were performed on a combined data set, as well as on each data set individually. Analyses of the combined data support loliginid monophyly and reveal four clades-one consisting primarily of species in American waters from two genera, one composed of 3 east Atlantic species, one consisting of the bioluminescent loliginids (uroteuthis sensu Vecchione et al,, 1998) plus Loliolus japonica and one represented by a Loligo (Alloteuthis) subulata-Lolliguncula mercatoris pair. The likelihood of the unconstrained maximum-likelihood tree is not significantly better than the likelihoods of the best trees constrained to Sepiotheuthis monophyly or Uroteuthis monophyly, but there is significant support for Lolliguncula polyphyly. Tests of alternative hypotheses of loliginid cladogenesis suggest that cladogenesis within Loliginidae is correlated with the widening of the Atlantic and the closure of the Tethys Sea, although dispersal from the Indo-West Pacific is a reasonable explanation for the origin of the clade of American loliginines. (C) 2000 Academic Press. C1 Smithsonian Inst, Lab Mol Systemat, Washington, DC 20560 USA. RP Anderson, FE (reprint author), So Illinois Univ, Dept Zool, Carbondale, IL 62901 USA. NR 52 TC 61 Z9 86 U1 0 U2 14 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1055-7903 J9 MOL PHYLOGENET EVOL JI Mol. Phylogenet. Evol. PD MAY PY 2000 VL 15 IS 2 BP 191 EP 214 DI 10.1006/mpev.1999.0753 PG 24 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 318MJ UT WOS:000087287700003 PM 10837151 ER PT J AU Bernardi, G Robertson, DR Clifton, KE Azzurro, E AF Bernardi, G Robertson, DR Clifton, KE Azzurro, E TI Molecular systematics, zoogeography, and evolutionary ecology of the Atlantic parrotfish genus Sparisoma SO MOLECULAR PHYLOGENETICS AND EVOLUTION LA English DT Article DE parrotfish; Scaridae; Sparisoma; molecular phylogeography; fish ecology ID DEPENDENT PERMUTATION TEST; GREAT-BARRIER-REEF; STOPLIGHT-PARROTFISH; FAMILY SCARIDAE; VIRIDE SCARIDAE; RIBOSOMAL-RNA; CONFIDENCE; AUSTRALIA; BOOTSTRAP; FOOD AB Parrotfishes of the genus Sparisoma (Scaridae) are ecologically important tropical reef fishes restricted to the Atlantic Ocean. We investigated phylogenetic relationships among the eight extant species within this genus using mitochondrially encoded 12S and 16S ribosomal genes. Our molecular data support the view that (i) Sparisoma originated similar to 14-35 million years ago (mya), probably in the tropical western Atlantic, off Brazil; (ii) there have been at least four discrete bouts of cladogenesis within the genus, with the most recent one (similar to 2.8-5.6 mya) involving four events in both the east and the west Atlantic and across the Atlantic; and (iii) the genus invaded the eastern Atlantic on two different occasions, probably by at least two different routes. The data also offer support for Bellwood's ideas concerning the evolutionary changes in adult feeding patterns and habitat use within Scarids. Specifically, they support the evolutionary position of the ecological traits of Sparisoma as intermediate within the family. (C) 2000 Academic Press. C1 Univ Calif Santa Cruz, Dept Biol, Santa Cruz, CA 95064 USA. Smithsonian Trop Res Inst, Balboa, Panama. ICRAM, Ist Ric Sci & Tecnol Applicata Mare, I-90136 Palermo, Italy. RP Bernardi, G (reprint author), Univ Calif Santa Cruz, Dept Biol, Santa Cruz, CA 95064 USA. EM bernardi@biology.ucsc.edu RI Bernardi, Giacomo/F-6346-2011 OI Bernardi, Giacomo/0000-0002-8249-4678 NR 46 TC 52 Z9 54 U1 3 U2 12 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1055-7903 EI 1095-9513 J9 MOL PHYLOGENET EVOL JI Mol. Phylogenet. Evol. PD MAY PY 2000 VL 15 IS 2 BP 292 EP 300 DI 10.1006/mpev.1999.0745 PG 9 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 318MJ UT WOS:000087287700010 PM 10837158 ER PT J AU Vignali, C Mignoli, M Comastri, A Maiolino, R Fiore, F AF Vignali, C Mignoli, M Comastri, A Maiolino, R Fiore, F TI Optical, near-infrared and hard X-ray observations of SAXJ1353.9+1820: a red quasar SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : active; quasars : individual : SAXJ1353.9+1820; X-rays : galaxies ID ASCA; GALAXY; SPECTROSCOPY; ABUNDANCES; ABSORPTION; SPECTRUM; COLORS; FAINT; QSO AB We present the results of a follow-up ASCA observation and multicolour optical and near-infrared photometry carried out at the 3.5-m Italian National Telescope Galileo of SAX J1353.9+1820. This object, serendipitously discovered by BeppoSAX in the 5-10 keV band, has been spectroscopically identified as a red quasar at z = 0.217. The combined X-ray and optical-infrared data reveal the presence of a moderately luminous X-ray source (similar to 10(44) erg s(-1)) obscured by a column density of the order of 10(22) cm(-2) in an otherwise optically passive early-type galaxy. The implications for the nature of red quasars and their possible contribution to the hard X-ray background are briefly outlined. C1 Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy. Osservatorio Astron Bologna, I-40127 Bologna, Italy. Osservatorio Astrofis Arcetri, I-50125 Florence, Italy. Osservatorio Astron Roma, I-00044 Monteporzio, Italy. BeppoSAX Sci Data Ctr, I-00131 Rome, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Vignali, C (reprint author), Univ Bologna, Dipartimento Astron, Via Ranzani 1, I-40127 Bologna, Italy. RI Vignali, Cristian/J-4974-2012; Mignoli, Marco/O-9426-2015; Comastri, Andrea/O-9543-2015 OI Vignali, Cristian/0000-0002-8853-9611; Mignoli, Marco/0000-0002-9087-2835; Comastri, Andrea/0000-0003-3451-9970 NR 37 TC 11 Z9 11 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 1 PY 2000 VL 314 IS 1 BP L11 EP L15 DI 10.1046/j.1365-8711.2000.03508.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 317CY UT WOS:000087209800003 ER PT J AU Hill, RW AF Hill, RW TI The Museum Indian: Still frozen in time (Exhibitions depicting Native Americans) SO MUSEUM NEWS LA English DT Article C1 Smithsonian Inst, Washington, DC 20560 USA. RP Hill, RW (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 1 Z9 1 U1 0 U2 1 PU AMER ASSOC MUSEUMS PI WASHINGTON PA 1575 EYE ST, NW, STE 400, WASHINGTON, DC 20005 USA SN 0027-4089 J9 MUSEUM NEWS JI Mus. News PD MAY-JUN PY 2000 VL 79 IS 3 BP 40 EP + PG 0 WC Art SC Art GA 311BR UT WOS:000086865100016 ER PT J AU West, WR AF West, WR TI Creating the community-conscious museum SO MUSEUM NEWS LA English DT Editorial Material C1 Smithsonian Inst, Washington, DC 20560 USA. RP West, WR (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC MUSEUMS PI WASHINGTON PA 1575 EYE ST, NW, STE 400, WASHINGTON, DC 20005 USA SN 0027-4089 J9 MUSEUM NEWS JI Mus. News PD MAY-JUN PY 2000 VL 79 IS 3 BP 107 EP 107 PG 1 WC Art SC Art GA 311BR UT WOS:000086865100020 ER PT J AU Lukin, MD Yelin, SF Fleischhauer, M AF Lukin, MD Yelin, SF Fleischhauer, M TI Entanglement of atomic ensembles by trapping correlated photon states SO PHYSICAL REVIEW LETTERS LA English DT Article ID PODOLSKY-ROSEN CHANNELS; QUANTUM STATE; SQUEEZED-LIGHT; GROUP-VELOCITY; SPECTROSCOPY; COMPUTATION; NOISE; TELEPORTATION; REALIZATION; COHERENCE AB We describe a general technique that allows for an ideal transfer of quantum correlations between light fields and metastable states of matter. The technique is based on trapping quantum states of photons in coherently driven atomic media, in which the group velocity is abiabatically reduced to zero. We discuss possible applications such as quantum state memories, generation of squeezed atomic states, preparation of entangled atomic ensembles, quantum information processing, and quantum networking. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Univ Munich, Sekt Phys, D-80333 Munich, Germany. RP Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RI Fleischhauer, Michael/G-6716-2011 NR 36 TC 315 Z9 325 U1 2 U2 21 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 1 PY 2000 VL 84 IS 18 BP 4232 EP 4235 DI 10.1103/PhysRevLett.84.4232 PG 4 WC Physics, Multidisciplinary SC Physics GA 309YN UT WOS:000086797300054 ER PT J AU Keto, E AF Keto, E TI Three-phase switching with m-sequences for sideband separation in radio interferometry SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID MILLIMETER AB Orthogonal sequences known as m-sequences can be used in place of Walsh functions in phase switching and sideband separation in cross-correlation interferometers. Functions based on three-character m-sequences may be advantageous because they may provide a larger set of mutually orthogonal modulation and demodulation functions, and hence support a larger number of antennas for a given sequence length, than allowed by other orthogonal sequences such as Walsh functions. The reason for this advantage is that if the demodulation functions are formed from the differences of the three-character m-sequence modulation functions, then because the m-sequences obey an addition rule whereby sums or differences of m-sequences are also m-sequences, the demodulation functions are also members of the original orthogonal set. In a complete set of sequences, all the differences are of course duplicates of the original sequences. However, certain subsets of sequences have differences which are not members of the subset, and these subsets can be used to form modulation and demodulation functions which have both the desired uniqueness and orthogonality properties. While it is not obvious how to select the subsets, heuristic methods seem reasonably successful. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Keto, E (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD MAY PY 2000 VL 112 IS 771 BP 711 EP 715 DI 10.1086/316560 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 319UF UT WOS:000087360200013 ER PT J AU Millan-Gabet, R AF Millan-Gabet, R TI Investigation of Herbig Ae/Be stars in the near-infrared with a long-baseline interferometer SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article C1 Univ Massachusetts, Amherst, MA 01003 USA. RP Millan-Gabet, R (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD MAY PY 2000 VL 112 IS 771 BP 742 EP 743 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 319UF UT WOS:000087360200016 ER PT J AU Ball, AS Milne, E Drake, BG AF Ball, AS Milne, E Drake, BG TI Elevated atmospheric-carbon dioxide concentration increases soil respiration in a mid-successional lowland forest SO SOIL BIOLOGY & BIOCHEMISTRY LA English DT Article ID BIOMASS ALLOCATION; ROOT PRODUCTION; CO2 ENRICHMENT; GROWTH; NITROGEN; VEGETATION; RESPONSES C1 Univ Essex, John Tabor Labs, Dept Biol Sci, Colchester CO4 3SQ, Essex, England. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Ball, AS (reprint author), Univ Essex, John Tabor Labs, Dept Biol Sci, Wivenhoe Pk, Colchester CO4 3SQ, Essex, England. RI Milne, Eleanor/A-2654-2008 NR 16 TC 7 Z9 17 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-0717 J9 SOIL BIOL BIOCHEM JI Soil Biol. Biochem. PD MAY PY 2000 VL 32 IS 5 BP 721 EP 723 DI 10.1016/S0038-0717(99)00198-4 PG 3 WC Soil Science SC Agriculture GA 312RP UT WOS:000086956900016 ER PT J AU Morrow, CJ Wolfe, BA Roth, TL Wildt, DE Bush, M Blumer, ES Atkinson, MW Monfort, SL AF Morrow, CJ Wolfe, BA Roth, TL Wildt, DE Bush, M Blumer, ES Atkinson, MW Monfort, SL TI Comparing ovulation synchronization protocols for artificial insemination in the scimitar-horned oryx (Oryx dammah) SO ANIMAL REPRODUCTION SCIENCE LA English DT Article DE scimitar-horned oryx; artificial insemination; faecal steroid; ovulation induction; ultrasound ID FARMED FALLOW DEER; GENETIC RESOURCE BANKS; IN-VITRO FERTILIZATION; ESTROUS SYNCHRONIZATION; DAMA-DAMA; LUTEINIZING-HORMONE; OVARIAN ACTIVITY; ESTRUS; SEMEN; CRYOPRESERVATION AB Ovarian response and pregnancy success in scimitar-homed oryx (n = 28) were compared, following treatment with two synchronization protocols and fixed-time artificial insemination (AI) with frozen-thawed semen. Each oryx received two injections of 500 mu g of prostaglandin-F-2 alpha analogue (PGF(2 alpha)-only) 11 days apart, and half received PGF(2 alpha) in combination with an intravaginal progesterone-releasing device (CIDR11 + PGF(2 alpha)), Semen was collected by electroejaculation from anaesthetised adult oryx and cryopreserved. Anaesthetised females were transcervically inseminated 56.0 +/- 1.1 h (+/-S.E.M.) after PGF(2 alpha) injection and/or device withdrawal using 28.0 +/- 1.5 x 10(6) motile thawed sperm. Ovarian endocrine response was monitored in 20 females by analysing faecal oestrogen and progesterone metabolites. Periovulatory oestrogen peaks were detected in 19/20 (95%) females after synchronization. There were no between-treatment differences in oestrogen concentrations or peak characteristics (P > 0.05). Luteal development after synchronization was delayed in half the progesterone treated (CIDR11 + PGF(2 alpha)) females, and faecal progestin excretion profiles indicated that the ovulatory follicle associated with synchronization either failed to ovulate or to fully lutenise. Pregnancy was diagnosed by ultrasonography and/or rectal palpation and was monitored by faecal progestin excretion. More (P = 0.013) pregnancies resulted from the PGF(2 alpha)-only treatment (37.5%, 5/14) than from the CIDR11 + PGF(2 alpha) treatment (0/14), and four healthy scimitar-horned oryx calves were born, three after gestation intervals of 247 days and one after 249 days. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Smithsonian Inst, Consservat & Res Ctr, Natl Zool Pk, Front Royal, VA 22630 USA. George Mason Univ, Fairfax, VA 22030 USA. The Wilds, Cumberland, OH 43732 USA. RP Morrow, CJ (reprint author), AgRes, Ruakura Agr Ctr, Private Bag 3132, Hamilton, New Zealand. NR 41 TC 32 Z9 33 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4320 J9 ANIM REPROD SCI JI Anim. Reprod. Sci. PD APR 28 PY 2000 VL 59 IS 1-2 BP 71 EP 86 DI 10.1016/S0378-4320(00)00067-1 PG 16 WC Agriculture, Dairy & Animal Science; Reproductive Biology SC Agriculture; Reproductive Biology GA 312NE UT WOS:000086948700007 PM 10804277 ER PT J AU Gingerich, O AF Gingerich, O TI Cardano's cosmos: The worlds and works of a Renaissance astrologer SO NATURE LA English DT Book Review C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gingerich, O (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 27 PY 2000 VL 404 IS 6781 BP 928 EP 929 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 309HG UT WOS:000086762000025 ER PT J AU Cook, AC Robinson, MS AF Cook, AC Robinson, MS TI Mariner 10 stereo image coverage of Mercury SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID EASTERN LIMB; CLEMENTINE; MOON; TOPOGRAPHY AB A computer search was performed on all useable Mariner 10 images of Mercury for which refined camera positions and orientations are available. Over 2000 valid stereo pairs have been found. The results of this search allowed us to construct a map illustrating the available stereo coverage and the corresponding stereo height accuracy across the surface of Mercury. Examples are given to illustrate the quality of the available stereo pairs and the resulting digital elevation models. C1 Smithsonian Inst, Ctr Earth & Planetary Studies, Natl Air & Space Museum, Washington, DC 20560 USA. Northwestern Univ, Dept Geol Sci, Evanston, IL 60208 USA. RP Cook, AC (reprint author), Smithsonian Inst, Ctr Earth & Planetary Studies, Natl Air & Space Museum, Washington, DC 20560 USA. NR 46 TC 19 Z9 20 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 25 PY 2000 VL 105 IS E4 BP 9429 EP 9443 DI 10.1029/1999JE001135 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 306HG UT WOS:000086590800001 ER PT J AU Okumura, SK Momose, M Kawaguchi, N Kanzawa, T Tsutsumi, T Suzuki, T Ozeki, K Natori, K Hashimoto, T AF Okumura, SK Momose, M Kawaguchi, N Kanzawa, T Tsutsumi, T Suzuki, T Ozeki, K Natori, K Hashimoto, T TI 1-GHz bandwidth digital spectro-correlator system for the Nobeyama Mllimeter Aray SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN LA English DT Article DE instrumentation : interferometers; radio continuum : general; radio lines : general; techniques : signal processing; techniques : spectroscopic ID INTERFEROMETRY AB We have developed 1-GHz bandwidth digital spectro-correlator system for the Nobeyama Millimeter Array (NMA). It consists of 2Gsample/sec.2bit analog-to-digital (A/D) converters and an ultra-wide band digital correlator. We developed two kinds of special-purpose LSI having functions of delay compensation and correlation, respectively. With these LSIs, the ultra-wide band digital correlator realizes 1024-MHz bandwidth spectroscopy with 128-channel resolution for 15-correlation data. This system allows us to observe radio continuum emission with about a two-times better signal-to-noise ratio than that of the previous correlator system. We started common-use observations with this new system from 1997 March; the system has been extended in order to obtain 21-correlation data for a 7-element "Rainbow" (NMA + 45-m telescope) interferometer system. C1 Natl Astron Observ, Nobeyama Radio Observ, Minamisa Ku, Nagano 3841305, Japan. Natl Astron Observ, Mitaka, Tokyo 1818588, Japan. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Tokyo Electron Ltd, Yamanashi 4078511, Japan. Nihon Tsushinki Co Ltd, Yamoto, Kanagawa 2420018, Japan. Oki Elect Ind Co Ltd, Minato Ku, Tokyo 1088551, Japan. RP Natl Astron Observ, Nobeyama Radio Observ, Minamisa Ku, Nagano 3841305, Japan. EM sokumura@nro.nao.ac.jp NR 11 TC 72 Z9 72 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0004-6264 EI 2053-051X J9 PUBL ASTRON SOC JPN JI Publ. Astron. Soc. Jpn. PD APR 25 PY 2000 VL 52 IS 2 BP 393 EP 400 DI 10.1093/pasj/52.2.393 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 310ZJ UT WOS:000086859400019 ER PT J AU Perna, R Raymond, J Loeb, A AF Perna, R Raymond, J Loeb, A TI Identifying gamma-ray burst remnants in nearby galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : clusters : individual (Virgo); gamma rays : bursts; ISM : general ID CROSS-SECTIONS; FIREBALL MODEL; CYGNUS LOOP; SHOCK-WAVES; AFTERGLOW; PARAMETERS; EXPLOSIONS; SPECTRA; OBJECTS; STARS AB We study the spectral signatures arising from cooling and recombination of an interstellar medium whose equilibrium state has been altered over similar to 100 pc by the radiation of a gamma-ray burst (GRB) and its afterglow. We identify signatures in the line diagnostics that are indicative of a photoionized GRB remnant which is less than or similar to 5 x 10(4) yr old. We estimate that at least a few such remnants should be detectable in the Virgo Cluster of galaxies. If the gamma-ray emission from GRBs is beamed to a fraction f(b) of their sky, then the expected number of Virgo remnants is larger by a factor of f(b)(-1). Virgo remnants can be resolved with arcsecond imaging and are likely to be center-filled using narrowband filters of high-ionization lines (such as [O III] lambda 5007 or He II lambda 4686) and limb-brightened for low-ionization lines (such as [S II] lambda 6717). The nonrelativistic blast wave might be visible separately, since it does not reach the outer edge of these young photoionized remnants. The remnants should show evidence for ionization cones if the prompt or afterglow UV emission from GRBs is beamed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Perna, R (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 50 TC 36 Z9 38 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2000 VL 533 IS 2 BP 658 EP 669 DI 10.1086/308682 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 313GA UT WOS:000086990900008 ER PT J AU Cuntz, M Saar, SH Musielak, ZE AF Cuntz, M Saar, SH Musielak, ZE TI On stellar activity enhancement due to interactions with extrasolar giant planets SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : general; planetary systems; stars : activity; stars : chromospheres; stars : coronae; stars : late-type ID LONGITUDINAL TUBE WAVES; SOLAR-TYPE STARS; UPSILON-ANDROMEDAE; PARENT STARS; GENERATION; CONVECTION; ROTATION; CATALOG; DYNAMO AB We present a first attempt to identify and quantify possible interactions between recently discovered extrasolar giant planets (and brown dwarfs) and their host stars, resulting in activity enhancement in the stellar outer atmospheres. Many extrasolar planets have masses comparable to or larger than Jupiter and are within a distance of 0.5 AU, suggesting the possibility of their significant influence on stellar winds, coronae, and even chromospheres. Beyond the well-known rotational synchronization, the interactions include tidal effects (in which enhanced flows and turbulence in the tidal bulge lead to increased magnetoacoustic heating and dynamo action) and direct magnetic interaction between the stellar and planetary magnetic fields. We discuss relevant parameters for selected systems and give preliminary estimates of the relative interaction strengths. C1 Univ Alabama, Ctr Space Plasma & Aeron & Astrophys Res, Huntsville, AL 35899 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Texas, Dept Phys, Arlington, TX 76019 USA. RP Cuntz, M (reprint author), Univ Alabama, Ctr Space Plasma & Aeron & Astrophys Res, Huntsville, AL 35899 USA. NR 51 TC 122 Z9 122 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2000 VL 533 IS 2 BP L151 EP L154 DI 10.1086/312609 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 313GC UT WOS:000086991100020 ER PT J AU Daw, A Parkinson, WH Smith, PL Calamai, AG AF Daw, A Parkinson, WH Smith, PL Calamai, AG TI Transition probabilities for the 1815 and 3344 angstrom forbidden lines of NeIII SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic data; techniques : spectroscopic; ultraviolet : general ID ISOELECTRONIC SEQUENCE; IONS; CONFIGURATION AB We have measured the radiative lifetime of the 2s(2)2p(4) S-1(0) metastable level of Ne2+ (Ne III) to be 223 +/- 11 ms at the 90% confidence level by observing the photons emitted at 1815 Angstrom by a decaying population of S-1(0) Ne2+ ions produced and stored in a radio-frequency ion trap. This is the first lifetime measurement for an excited term of a ground configuration ion in the second row of the periodic table. The transition probabilities (A-values) for the forbidden transitions in the ground configurations of these ions are required for astrophysical line-ratio diagnostics. Using calculated branching ratios, we estimate that A(lambda 1815)= 1.94 +/- 0.17 and A(lambda 3344)= 2.55 +/- 0.19 s(-1). Because these numbers have a sum with an experimentally determined uncertainty of 5%, they will provide more accurate results than the calculated A-values for determining electron temperature and density from astrophysical Ne III line ratios. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. St Josephs Univ, Philadelphia, PA 19131 USA. RP Daw, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI daw, adrian/D-2297-2012 NR 19 TC 5 Z9 5 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2000 VL 533 IS 2 BP L179 EP L182 DI 10.1086/312605 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 313GC UT WOS:000086991100027 ER PT J AU Korzennik, SG Brown, TM Fischer, DA Nisenson, P Noyes, RW AF Korzennik, SG Brown, TM Fischer, DA Nisenson, P Noyes, RW TI A high-eccentricity low-mass companion to HD 89744 SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems; stars : individual (HD 89744); stars : low-mass, brown dwarfs techniques : radial velocities ID CHEMICAL EVOLUTION; STARS; 16-CYGNI-B; DOPPLER; PLANETS AB HD 89744 is an F7 V star with a mass of 1.4 M., an effective temperature of 6166 K, an age of 2.0 Gyr, and metallicity [Fe/H] = 0.18. The radial velocity of the star has been monitored with the Advanced Fiber-Optic Echelle spectrograph at the Whipple Observatory since 1996, and evidence has been found for a low-mass companion. The data were complemented by additional data from the Hamilton spectrograph at Lick Observatory during the companion's periastron passage in the fall of 1999. As a result, we have determined the star's orbital wobble to have a period P = 256 days, an orbital amplitude K = 257 m s(-1), and an eccentricity e = 0.7. From the stellar mass, we infer that the companion has a minimum mass m(2) sin i = 7.2 M-J in an orbit with a semimajor axis a(2) = 0.88 AU. The eccentricity of the orbit, among the highest known for extrasolar planets, continues the trend that extrasolar planets with semimajor axes greater than about 0.15 AU tend to have much higher eccentricities than are found in our solar system. The high metallicity of the parent star reinforces the trend that parent stars of extrasolar planets tend to have high metallicity. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Korzennik, SG (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 26 TC 43 Z9 43 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2000 VL 533 IS 2 BP L147 EP L150 DI 10.1086/312611 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 313GC UT WOS:000086991100019 ER PT J AU Kurtz, MJ Mink, DJ AF Kurtz, MJ Mink, DJ TI Eigenvector sky subtraction SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : distances and redshifts; methods : data analysis; techniques : spectroscopic ID CONVERTED MMT; SPECTROGRAPH; HECTOSPEC; REDSHIFTS AB We develop a new method for estimating and removing the spectrum of the sky from deep spectroscopic observations. Our method does not rely on simultaneous measurement of the sky spectrum with the object spectrum. The technique is based on the iterative subtraction of continuum estimates and eigenvector sky models derived from singular value decompositions of sky spectra and sky spectra residuals. Using simulated data derived from small-telescope observations, we demonstrate that the method is effective for faint objects on large telescopes. We discuss simple methods to combine our new technique with the simultaneous measurement of sky to obtain sky subtraction very near the Poisson limit. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kurtz, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI KURTZ, Michael /B-3890-2009 NR 19 TC 10 Z9 11 U1 1 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2000 VL 533 IS 2 BP L183 EP L186 DI 10.1086/312620 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 313GC UT WOS:000086991100028 ER PT J AU Mathur, S Green, PJ Arav, N Brotherton, M Crenshaw, M DeKool, M Elvis, M Goodrich, RW Hamann, F Hines, DC Kashyap, V Korista, K Peterson, BM Shields, JC Shlosman, I van Breugel, W Voit, M AF Mathur, S Green, PJ Arav, N Brotherton, M Crenshaw, M DeKool, M Elvis, M Goodrich, RW Hamann, F Hines, DC Kashyap, V Korista, K Peterson, BM Shields, JC Shlosman, I van Breugel, W Voit, M TI Thomson thick X-ray absorption in a broad absorption line quasar, PG 0946+301 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; quasars : absorption lines; quasars : individual (PG 0946+301); X-rays : galaxies ID ABUNDANCES; PHL-5200 AB We present a deep ASCA observation of a broad absorption line quasar (BALQSQ) PG 0946+301. The source was clearly detected in one of the gas imaging spectrometers, but not in any other detector. If BALQSOs have intrinsic X-ray spectra similar to normal radio-quiet quasars, our observations imply that there is Thomson thick X-ray absorption (N-H greater than or similar to 10(24) cm(-2)) toward PG 0946+301. This is the largest column density estimated so far toward a BALQSO. The absorber must be at least partially ionized and may be responsible for attenuation in the optical and UV. If the Thomson optical depth toward BALQSOs is close to 1, as inferred here, then spectroscopy in hard X-rays with large telescopes like XMM would be feasible. C1 Ohio State Univ, Columbus, OH 43220 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. Catholic Univ, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Australian Natl Univ, Res Sch Astron & Astrophys, Weston Creek, ACT 2611, Australia. WM Keck Observ, Kamuela, HI 96743 USA. Univ Florida, Gainesville, FL 32611 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Western Michigan Univ, Kalamazoo, MI 49008 USA. Ohio Univ, Athens, OH 45701 USA. Univ Kentucky, Lexington, KY 40506 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Mathur, S (reprint author), Ohio State Univ, Columbus, OH 43220 USA. NR 22 TC 30 Z9 30 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2000 VL 533 IS 2 BP L79 EP L82 DI 10.1086/312617 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 313GC UT WOS:000086991100003 ER PT J AU Laurance, WF Delamonica, P Laurance, SG Vasconcelos, HL Lovejoy, TE AF Laurance, WF Delamonica, P Laurance, SG Vasconcelos, HL Lovejoy, TE TI Conservation - Rainforest fragmentation kills big trees SO NATURE LA English DT Article ID FOREST C1 INPA, Biol Dynam Forest Fragments Project, BR-69011970 Manaus, Amazonas, Brazil. Smithsonian Inst, Washington, DC 20560 USA. RP Laurance, WF (reprint author), INPA, Biol Dynam Forest Fragments Project, CP 478, BR-69011970 Manaus, Amazonas, Brazil. RI Laurance, William/B-2709-2012; Vasconcelos, Heraldo/C-3353-2013; Laurance, Susan/G-6021-2011 OI Vasconcelos, Heraldo/0000-0001-6969-7131; Laurance, Susan/0000-0002-2831-2933 NR 12 TC 282 Z9 296 U1 4 U2 50 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 20 PY 2000 VL 404 IS 6780 BP 836 EP 836 DI 10.1038/35009032 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 306XY UT WOS:000086625000034 PM 10786782 ER PT J AU Bahrim, B Thumm, U AF Bahrim, B Thumm, U TI Charge-transfer dynamics in slow atom-surface collisions: A new close-coupling approach including continuum discretization SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 8th International Workshop on Desorption Induced by Electronic Transitions CY SEP 27-OCT 01, 1999 CL LONG BRANCH, NJ SP Army Res Off, Durham, Natl Sci Fdn, Ruters Lab Surface Modificat DE ab initio quantum chemical methods and calculations; ion-solid interactions; jellium models ID METAL-SURFACES; FRONT; IONS AB Within a new two-center close-coupling expansion, we solve the time-dependent Schrodinger equation for an active electron interacting with a slow projectile and a metal surface. The continuum of conduction-band states corresponding to the motion of the active electron in the metal subspace along the surface normal is discretized in terms of wave packets. Results for the time evolution of the atomic and metallic population amplitudes for an excited hydrogen atom near an aluminum surface are shown and discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Bahrim, B (reprint author), Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA. EM bahrimb@phys.ksu.edu; thumm@phys.ksu.edu OI Thumm, Uwe/0000-0001-9378-6601 NR 13 TC 4 Z9 4 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 20 PY 2000 VL 451 IS 1-3 BP 1 EP 6 DI 10.1016/S0039-6028(00)00002-9 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 308ZG UT WOS:000086742300002 ER PT J AU Fleischhauer, M Lukin, MD Matsko, AB Scully, MO AF Fleischhauer, M Lukin, MD Matsko, AB Scully, MO TI Threshold and linewidth of a mirrorless parametric oscillator SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; OPTICAL INSTABILITIES; SODIUM VAPOR; LASER; BEAMS AB We analyze the above-threshold behavior of a mirrorless parametric oscillator based on resonantly enhanced four-wave mixing in a dense atomic vapor. It is shown that, in the ideal limit, an arbitrary small flux of pump photons is sufficient to reach the oscillator threshold. We demonstrate that, due to the large group velocity delays associated with electromagnetically induced transparency, an extremely narrow oscillator linewidth is possible, making a narrow-band source of nonclassical radiation feasible. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Univ Munich, Sekt Phys, D-80333 Munich, Germany. Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. RP Fleischhauer, M (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RI Matsko, Andrey/A-1272-2007; Fleischhauer, Michael/G-6716-2011 NR 20 TC 30 Z9 30 U1 0 U2 6 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 17 PY 2000 VL 84 IS 16 BP 3558 EP 3561 DI 10.1103/PhysRevLett.84.3558 PG 4 WC Physics, Multidisciplinary SC Physics GA 304VH UT WOS:000086504500014 ER PT J AU Johnson, DG Jucks, KW Traub, WA Chance, KV AF Johnson, DG Jucks, KW Traub, WA Chance, KV TI Isotopic composition of stratospheric ozone SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID HEAVY OZONE; TROPOSPHERIC OZONE; MOLECULAR-OXYGEN; LINE POSITIONS; ATMOSPHERE; EXCHANGE; INTENSITIES; BANDS; O-18; NU-1 AB Using recently measured rates for isotopic variants of the ozone formation reaction O + O-2 + M, we derive expressions for the enrichment of symmetric and asymmetric O-50(3) and O-49(3) in stratospheric ozone and calculate total enrichments of 123 parts per thousand and 107 parts per thousand for O-50(3) and O-49(3), respectively. We compare the calculations with measurements made with the Smithsonian Astrophysical Observatory far-infrared spectrometer during seven balloon flights Which took place between 1989 and 1997, We find that the calculations are in reasonable agreement with the average observed enrichments of 102+/-43 parts per thousand and 73+/-60 parts per thousand for O-50(3) and O-49(3), respectively, where the errors indicate the estimated accuracy; we also find that our measurements are in agreement with other recent stratospheric and tropospheric measurements. Using our measurements of the enrichment of the asymmetric and symmetric forms of O-50(3) and O-49(3), We estimate branching ratios of 0.43+/-0.03 and 0.46+/-0.06 for production of the symmetric isotopomer by the reaction of O-16 with O-34(2) and O-33(2), respectively. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Johnson, DG (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. EM dgj@cfa.harvard.edu; kjucks@cfa.harvard.edu; wtraub@cfa.harvard.edu; kchance@cfa.harvard.edu RI Johnson, David/F-2376-2015; OI Johnson, David/0000-0003-4399-5653; Chance, Kelly/0000-0002-7339-7577 NR 25 TC 29 Z9 31 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 16 PY 2000 VL 105 IS D7 BP 9025 EP 9031 DI 10.1029/1999JD901167 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 306FJ UT WOS:000086586400010 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI The Faustian bargain: The art world in Nazi Germany. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Lib, Washington, DC 20560 USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Lib, Washington, DC 20560 USA. NR 1 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 2000 VL 125 IS 7 BP 82 EP 82 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 302QR UT WOS:000086377200038 ER PT J AU El-Ad, H Piran, T AF El-Ad, H Piran, T TI A case devoid of bias: Optical Redshift Survey voids versus IRAS voids SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : clusters : general; cosmology : observations; large-scale structure of Universe ID DENSITY FIELD; GALAXY DISTRIBUTION; UNIVERSE; VELOCITY AB We present a comparison between the voids in two nearly all-sky redshift surveys: the Optical Redshift Survey (ORS) and the IRAS 1.2-Jy survey. While the galaxies in these surveys are selected differently and their populations are known to be biased relative to each other, the two void distributions are similar. We compare the spatial distribution of the two void populations and demonstrate the correlation between them. The voids also agree with regard to the overall void statistics - a filling factor of approximate to 0.45 of the volume, an average void diameter (d) over bar(void)approximate to 45 h(-1) Mpc and an average galaxy underdensity in the voids <(delta)over bar>approximate to-0.9. Our measurements of the underdensities of the voids in the two surveys enable us to estimate the relative bias in the voids between optical and IRAS samples. We find (b(opt)/b(IRAS))(void)approximate to 1, showing that on average there is little - or no - biasing between the two void populations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. Columbia Univ, Dept Astron, New York, NY 10027 USA. NYU, Dept Phys, New York, NY 10003 USA. RP El-Ad, H (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 24 TC 32 Z9 32 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 11 PY 2000 VL 313 IS 3 BP 553 EP 558 DI 10.1046/j.1365-8711.2000.03286.x PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 302WU UT WOS:000086390100012 ER PT J AU Fleischmann, A Enss, C Schonefeld, J Sollner, J Horst, K Adams, JS Kim, YH Seidel, GM Bandler, SR AF Fleischmann, A Enss, C Schonefeld, J Sollner, J Horst, K Adams, JS Kim, YH Seidel, GM Bandler, SR TI The sensitivity of magnetic calorimeters with large heat capacity SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Workshop on Low-Temperature Detectors (LTD-8) CY AUG 15-20, 1999 CL DALFSEN, NETHERLANDS SP Technol Fdn, European Space Technol Ctr, Space Res Org Netherlands DE low-temperature particle detectors; magnetic calorimeters; heat capacity AB Magnetic sensors, based on the measurement of the magnetization of paramagnetic spins, possess characteristics that make them suitable for use with low-temperature calorimeters having large heat capacities. When the properties of the sensor. which can be calculated, are optimized for a given heat capacity, the energy resolution depends on heat capacity roughly as C-1/3. We have obtained an energy resolution of 135 eV at 6 keV with a calorimeter having a heat capacity of 4 x 10(-9) J/K. No deviations from a linear response with respect to energy were observed in the detector up to 136 keV. Prospects for the improvement of the performance of large calorimeters are discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Heidelberg, Inst Angew Phys, D-69120 Heidelberg, Germany. Brown Univ, Dept Phys, Providence, RI 02912 USA. Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Fleischmann, A (reprint author), Univ Heidelberg, Inst Angew Phys, D-69120 Heidelberg, Germany. RI Bandler, Simon/A-6258-2010 OI Bandler, Simon/0000-0002-5112-8106 NR 4 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 11 PY 2000 VL 444 IS 1-2 BP 100 EP 103 DI 10.1016/S0168-9002(99)01338-8 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 310JU UT WOS:000086823400024 ER PT J AU Silver, E Schnopper, H Bandler, S Murray, S Madden, N Landis, D Beeman, J Haller, E Barbera, M Tucker, G Gillaspy, J Takacs, E Porto, J AF Silver, E Schnopper, H Bandler, S Murray, S Madden, N Landis, D Beeman, J Haller, E Barbera, M Tucker, G Gillaspy, J Takacs, E Porto, J TI Laboratory astrophysics and microanalysis with NTD-germanium-based X-ray microcalorimeters SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Workshop on Low-Temperature Detectors (LTD-8) CY AUG 15-20, 1999 CL DALFSEN, NETHERLANDS SP Technol Fdn, European Space Technol Ctr, Space Res Org Netherlands AB With the ability to create cosmic plasma conditions in the laboratory it is possible to investigate the dependencies of key diagnostic X-ray lines on density, temperature, and excitation conditions that exist in astrophysical sources with X-ray optics and a high-resolution X-ray microcalorimeter. The same instrumentation call be coupled to scanning electron microscopes or X-ray fluorescence probes to analyze the elemental and chemical composition of electronic, biological, geological and particulate materials. We describe how our microcalorimeter and X-ray optics provide significantly improved capabilities for laboratory astrophysics and microanalysis. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Brown Univ, Providence, RI 02912 USA. Osservatorio Astron Palermo, Palermo, Italy. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Silver, E (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Bandler, Simon/A-6258-2010; OI Bandler, Simon/0000-0002-5112-8106; Barbera, Marco/0000-0002-3188-7420 NR 8 TC 16 Z9 16 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 11 PY 2000 VL 444 IS 1-2 BP 156 EP 160 DI 10.1016/S0168-9002(99)01349-2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 310JU UT WOS:000086823400036 ER PT J AU Schonefeld, J Enss, C Fleischmann, A Sollner, J Horst, K Adams, JS Kim, YH Seidel, GM Bandler, SR AF Schonefeld, J Enss, C Fleischmann, A Sollner, J Horst, K Adams, JS Kim, YH Seidel, GM Bandler, SR TI X-ray detection using magnetic calorimeters SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Workshop on Low-Temperature Detectors (LTD-8) CY AUG 15-20, 1999 CL DALFSEN, NETHERLANDS SP Technol Fdn, European Space Technol Ctr, Space Res Org Netherlands DE low-temperature particle detectors; magnetic calorimeters; SQUIDs AB Using a magnetic calorimeter, we have obtained an energy resolution of 13 eV in the detection of 6 keV X-rays. The calorimeter consisted of a 50 mu m diameter, 25 mu m thick Au sensor doped with 300 ppm Er. A 100 x 100 mu m square, 8 mu m thick Au absorber was attached to the sensor. At the operating temperature of 33 mK and with a held of 3 mT, the calorimeter had a heat capacity of 1.3 x 10(-12) J/K. With a magnetic calorimeter optimized for X-ray detection an order of magnitude improvement in resolution should be possible. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Heidelberg, Inst Angew Phys, D-69120 Heidelberg, Germany. Brown Univ, Dept Phys, Providence, RI 02912 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Schonefeld, J (reprint author), Univ Heidelberg, Inst Angew Phys, Albert Ueberle Str 3-5, D-69120 Heidelberg, Germany. RI Bandler, Simon/A-6258-2010 OI Bandler, Simon/0000-0002-5112-8106 NR 9 TC 7 Z9 7 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 11 PY 2000 VL 444 IS 1-2 BP 211 EP 213 DI 10.1016/S0168-9002(99)01361-3 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 310JU UT WOS:000086823400047 ER PT J AU Bandler, S Silver, E Schnopper, H Murray, S Barbera, M Madden, N Landis, D Beeman, J Haller, E Tucker, G AF Bandler, S Silver, E Schnopper, H Murray, S Barbera, M Madden, N Landis, D Beeman, J Haller, E Tucker, G TI NTD-GE-based microcalorimeter performance SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Workshop on Low-Temperature Detectors (LTD-8) CY AUG 15-20, 1999 CL DALFSEN, NETHERLANDS SP Technol Fdn, European Space Technol Ctr, Space Res Org Netherlands ID RAY AB Our group has been developing X-ray microcalorimeters consisting of neutron transmutation-doped (NTD) germanium thermistors attached to superconducting tin absorbers. We discuss the performance of single pixel X-rap detectors, and describe an array technology. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Osservatorio Astron Palermo, Palermo, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Brown Univ, Providence, RI 02912 USA. RP Bandler, S (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Bandler, Simon/A-6258-2010; OI Bandler, Simon/0000-0002-5112-8106; Barbera, Marco/0000-0002-3188-7420 NR 6 TC 10 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 11 PY 2000 VL 444 IS 1-2 BP 273 EP 277 DI 10.1016/S0168-9002(99)01389-3 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 310JU UT WOS:000086823400062 ER PT J AU Reese, ED Mohr, JJ Carlstrom, JE Joy, M Grego, L Holder, GP Holzapfel, WL Hughes, JP Patel, SK Donahue, M AF Reese, ED Mohr, JJ Carlstrom, JE Joy, M Grego, L Holder, GP Holzapfel, WL Hughes, JP Patel, SK Donahue, M TI Sunyaev-Zeldovich effect-derived distances to the high-redshift clusters MS 0451.6-0305 and Cl 0016+16 SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; cosmology : observations; distance scale; galaxies : clusters : individual (MS 0451.6-0305, Cl 0016+16) techniques : interferometric ID X-RAY-PROPERTIES; RELATIVISTIC CORRECTIONS; HUBBLE-CONSTANT; THERMAL BREMSSTRAHLUNG; PECULIAR VELOCITIES; COOLING FLOWS; HOT PLASMA; GALAXIES; ROSAT; H-0 AB We determine the distances to the z similar or equal to 0.55 galaxy clusters MS 0451.6-0305 and Cl 0016+16 from a maximum-likelihood joint fit to interferometric Sunyaev-Zeldovich effect (SZE) and X-ray observations. We model the intracluster medium (ICM) using a spherical isothermal beta model. We quantify the statistical and systematic uncertainties inherent to these direct distance measurements, and we determine constraints on the Hubble parameter for three different cosmologies. For an Omega(M) = 0.3, Omega(A) = 0.7 cosmology, these distances imply a Hubble constant of 63(-9-21)(+12+21) km s(-1) Mpc(-1), where the uncertainties correspond to statistical followed by systematic at 68% confidence. The best-fit H-0 is 57 km s(-1) Mgc(-1) for an open (Omega(M) = 0.3) universe and 52 km s(-1) Mpc(-1) for a flat (Omega(M) = 1) universe. C1 Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Huntsville, AL 35812 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. CEA Saclay, Serv Astrophys, F-91191 Gif Sur Yvette, France. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Reese, ED (reprint author), Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. RI Donahue, Megan/B-5361-2012; Holzapfel, William/I-4836-2015 NR 79 TC 74 Z9 74 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2000 VL 533 IS 1 BP 38 EP 49 DI 10.1086/308662 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309VL UT WOS:000086789900003 ER PT J AU Coil, AL Ho, PTP AF Coil, AL Ho, PTP TI The dynamics of molecular material within 15 parsecs of the Galactic center SO ASTROPHYSICAL JOURNAL LA English DT Article DE Galaxy : center; ISM : clouds; ISM : molecules ID SAGITTARIUS-A COMPLEX; CENTER REGION; SGR-A; RADIO; AMMONIA; EAST; GAS; SUBMILLIMETER; CLOUDS; MASERS AB We report the results of a five-field mosaic of the central 15 pc of the Galaxy in the (1, 1) and (2, 2) lines of NH,. Two narrow filaments or streamers are seen running parallel to the Galactic plane. The southern streamer appears to carry gas directly toward the nuclear region from the 20 km s(-1) cloud. The eastern streamer, which we will denote the molecular ridge, appears to be the denser part of the 50 km s(-1) cloud that lies immediately east of the Sgr A East complex and extends in the south toward the 20 km s(-1) cloud. This ridge of gas carries the kinematical signatures of interactions with Sgr A East as well as a supernova remnant that lies south of the Galactic center. The bulk motion of the gas, the enhanced line widths, and the heating of the molecular material all suggest an active evolutionary phase for the gas immediately adjacent to the nucleus. C1 Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Coil, AL (reprint author), Univ Calif Berkeley, Dept Astron, 601 Campbell Hall, Berkeley, CA 94720 USA. NR 26 TC 62 Z9 63 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2000 VL 533 IS 1 BP 245 EP 259 DI 10.1086/308650 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309VL UT WOS:000086789900022 ER PT J AU Barret, D Olive, JF Boirin, L Done, C Skinner, GK Grindlay, JE AF Barret, D Olive, JF Boirin, L Done, C Skinner, GK Grindlay, JE TI Hard X-ray emission from low-mass X-ray binaries SO ASTROPHYSICAL JOURNAL LA English DT Review DE accretion, accretion disks; black hole physics; stars : individual (1E 1724-3045; GS 1826-238, SLX 1735-269, KS 1731-260) stars : neutron; X-rays : bursts; X-rays : stars ID QUASI-PERIODIC OSCILLATIONS; BLACK-HOLE CANDIDATES; ADVECTION-DOMINATED ACCRETION; GLOBULAR-CLUSTER TERZAN-2; BULGE SOURCE SLX-1735-269; ACTIVE GALACTIC NUCLEI; NEUTRON-STARS; TIMING-EXPLORER; SPECTRAL EVOLUTION; BURSTER KS-1731-260 AB We report on Rossi X-Ray Timing Explorer observations of four type I X-ray bursters, namely, 1E 1724-3045, GS 1826-238, SLX 1735-269, and KS 1731-260. The first three were in a low state, with 1-200 keV X-ray luminosities in the range similar to 0.05-0.1L(Edd) (L-Edd: Eddington luminosity for a neutron star, L-Edd = 2.5 x 10(38) ergs s(-1)), whereas KS 1731-260 was in a high state, with luminosity similar to 0.35L(Edd). The low-state sources have very similar power spectra, displaying high-frequency noise up to similar to 200 Hz. For KS 1731-260, its power spectrum is dominated by noise at frequencies less than or similar to 20 Hz; in addition a quasi-periodic oscillation at 1200 Hz is detected in a segment of the observation. The 1-200 keV spectra of the low-state sources are all consistent with resulting from thermal Comptonization with an electron temperature (kT(e)) around 25-30 keV. For KS 1731-260, the spectrum is also dominated by thermal Comptonization, but with a much lower kT(e) similar to 3 keV and no significant hard X-ray emission. With the exception of GS 1826-238, they each have an underlying soft component, carrying at most similar to 25% of the total 1-200 keV luminosity. For all sources, we have detected an iron ga line at 6.4 keV (although it is weak and marginal in 1E 1724-3045). A reflection component is present in the spectra of GS 1826-238 and SLX 1735-269, and for both we find that the reflecting medium subtends only a small solid angle (Omega 2/2 pi similar to 0.15, 0.28). The origin of the line and the reflection component is most likely to be irradiation of the accretion disk by the X-ray source. We suggest a model in which the region of main energy release, where hard X-rays are produced, would be an optically thin boundary layer merged with an advection-dominated accretion flow (ADAF) and would be responsible for the rapid variability observed. The soft component observed probably represents the unscattered emission from an optically thick accretion disk of variable inner radius. When the accretion rate increases, the inner disk radius shrinks and the strength of the reflected component and associated iron line increase. At the same time, the Comptonization region cools off in response to an increased cooling flux from the accretion disk and from the reprocessed/reflected component, thus leading progressively to a quenching of the hard X-ray emission. If low-state neutron stars (NSs) accrete via ADAFs, the observation of X-ray bursts, indicating that all the accreting matter actually accumulates onto the NS surface, argues against the existence of strong winds from such accretion flows. Finally, we discuss two criteria recently proposed to distinguish between nonquiescent black holes (BHs) and NSs that are not contradicted by existing observations. The first one states that, when thermal Comptonization is responsible for the hard X-ray emission, only BHs have kT(e) larger than similar to 50 keV. However, this criterion is weakened by the fact that there are NSs displaying nonattenuated power laws extending up to at least 200 keV, possibly implying nonthermal Comptonization or thermal Comptonization with kT(e) larger than 50 keV. The second criterion stipulates that only BHs are capable of emitting hard X-ray tails with 20-200 keV luminosities greater than or similar to 1.5 x 10(37) ergs s(-1). C1 Univ Toulouse 3, Ctr Etud Spatiale Rayonnements, CNRS, F-31028 Toulouse 04, France. Univ Durham, Dept Phys, Durham DH1 3LE, England. Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Univ Toulouse 3, Ctr Etud Spatiale Rayonnements, CNRS, 9 Ave Colonel Roche, F-31028 Toulouse 04, France. EM Didier.Barret@cesr.fr; chris.done@durham.ac.uk; gks@star.sr.bham.ac.uk; josh@head-cfa.harvard.edu RI done, chris/D-4605-2016 OI done, chris/0000-0002-1065-7239 NR 142 TC 166 Z9 166 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2000 VL 533 IS 1 BP 329 EP 351 DI 10.1086/308651 PN 1 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309VL UT WOS:000086789900029 ER PT J AU Muench, AA Lada, EA Lada, CJ AF Muench, AA Lada, EA Lada, CJ TI Modeling the near-infrared luminosity functions of young stellar clusters SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; open clusters and associations : general; stars : interiors; stars : low-mass, brown dwarfs; stars : luminosity function, mass function; stars : pre-main sequence ID LOW-MASS STARS; COLOR-MAGNITUDE DIAGRAMS; MAIN-SEQUENCE; M-DWARFS; EFFECTIVE TEMPERATURES; BOLOMETRIC CORRECTIONS; TURBULENT CONVECTION; SPECTRAL SEQUENCE; EMBEDDED CLUSTERS; MOLECULAR CLOUD AB We present the results of numerical experiments designed to evaluate the usefulness of near-infrared (NIR) luminosity functions for constraining the initial mass function (IMF) of young stellar populations. We test the sensitivity of the NIR K-band luminosity function (KLF) of a young stellar cluster to variations in the underlying IMF, star-forming history, and pre-main-sequence mass-to-luminosity relations. Using Monte Carlo techniques, we create a suite of model luminosity functions systematically varying each of these basic underlying relations. From this numerical modeling, we find that the luminosity function of a young stellar population is considerably more sensitive to variations in the underlying initial mass function than to either variations in the star-forming history or assumed pre-main-sequence (PMS) mass-to-luminosity relation. Variations in a cluster's star-forming history are also found to produce significant changes in the KLF. In particular, we find that the KLFs of young clusters evolve in a systematic manner with increasing mean age. Our experiments indicate that variations in the PMS mass-to-luminosity relation, resulting from differences in adopted PMS tracks, produce only small effects on the form of the model luminosity functions and that these effects are mostly likely not detectable observationally. To illustrate the potential effectiveness of using the KLF of a young cluster to constrain its IMF, we model the observed KLF of the nearby Trapezium cluster. With knowledge of the star-forming history of this cluster obtained from optical spectroscopic studies, we derive the simplest underlying IMF whose model luminosity function matches the observations. Our derived mass function for the Trapezium spans 2 orders of magnitude in stellar mass (5 > M. > 0.02) and has a peak near the hydrogen-burning limit. Below the hydrogen-burning limit, the mass function steadily decreases with decreasing mass throughout the brown dwarf regime. Comparison of our IMF with that derived by optical and spectroscopic methods for the entire Orion Nebula Cluster suggests that modeling the KLF is indeed a useful tool for constraining the mass function in young stellar clusters particularly at and below the hydrogen-burning limit. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florida, Dept Astron, Gainesville, FL 32611 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 42, Cambridge, MA 02138 USA. EM gmuench@cfa.harvard.edu; lada@astro.ufl.edu; clada@cfa.harvard.edu NR 58 TC 62 Z9 62 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 10 PY 2000 VL 533 IS 1 BP 358 EP 371 DI 10.1086/308638 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309VL UT WOS:000086789900031 ER PT J AU Gregersen, EM Evans, NJ Mardones, D Myers, PC AF Gregersen, EM Evans, NJ Mardones, D Myers, PC TI Does infall end before the class I stage? SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : formation; stars : pre-main-sequence; submillimeter ID YOUNG STELLAR OBJECTS; OB1 MOLECULAR CLOUD; FAR-INFRARED OBSERVATIONS; HERBIG-HARO OBJECTS; HIGH-VELOCITY GAS; DENSE CORES; SPECTROSCOPIC EVIDENCE; PROTOSTELLAR COLLAPSE; BIPOLAR OUTFLOWS; EMBEDDED STARS AB We have observed HCO+ J = 3-2 toward 16 class I sources and 18 class 0 sources, many of which were selected from Mardones et al.'s recent observations. Eight sources have profiles significantly skewed to the blue relative to optically thin lines. We suggest six sources as new infall candidates. We find an equal "blue excess" among class 0 and class I sources after combining this sample with that of Gregersen et al. We used a Monte Carlo code to simulate the temporal evolution of line profiles of optically thick lines of HCO+, CS, and H2CO in a collapsing cloud and found that HCO+ had the strongest asymmetry at late times. If a blue-peaked line profile implies infall, then the dividing line between the two classes does not trace the end of the infall stage. C1 McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. Univ Chile, Dept Astron, Santiago, Chile. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gregersen, EM (reprint author), McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. RI Mardones, Diego/I-5719-2016 NR 69 TC 47 Z9 47 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2000 VL 533 IS 1 BP 440 EP 453 DI 10.1086/308665 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309VL UT WOS:000086789900038 ER PT J AU Slane, P Chen, Y Schulz, NS Seward, FD Hughes, JP Gaensler, BM AF Slane, P Chen, Y Schulz, NS Seward, FD Hughes, JP Gaensler, BM TI Chandra observations of the Crab-like supernova remnant G21.5-0.9 SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (G21.5-0.9); supernova remnants; X-rays : ISM ID X-RAY-EMISSION; PULSARS; ENVIRONMENT; NEBULAE; INDEX; 3C-58 AB Chandra observations of the Crab-like supernova remnant G21.5 - 0.9 reveal a compact central core and spectral variations indicative of synchrotron burn-off of higher energy electrons in the inner nebula. The central core is slightly extended, perhaps indicating the presence of an inner wind-shock nebula surrounding the pulsar. No pulsations are observed from the central region, yielding an upper limit of similar to 40% for the pulsed fraction. A faint outer shell may be the first evidence of the expanding ejecta and blast wave formed in the initial explosion, indicating a composite nature for G21.5-0.9. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Nanjing Univ, Dept Astron, Nanjing 210093, Peoples R China. MIT, Ctr Space Res, Cambridge, MA 02139 USA. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. CEA Saclay, Serv Astrophys, F-91191 Gif Sur Yvette, France. RP Slane, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Gaensler, Bryan/F-8655-2010 NR 27 TC 77 Z9 78 U1 2 U2 3 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 APR 10 PY 2000 VL 533 IS 1 BP L29 EP L32 DI 10.1086/312589 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309VN UT WOS:000086790100008 ER PT J AU Song, I Caillault, JP Navascues, DB Stauffer, JR Randich, S AF Song, I Caillault, JP Navascues, DB Stauffer, JR Randich, S TI Ages of late spectral type Vega-like stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems; stars : activity; stars : late-type ID ALL-SKY SURVEY; BROWN DWARF CANDIDATES; MAIN-SEQUENCE STARS; SOLAR-TYPE STARS; PRECISE DETERMINATION; SURVEY CATALOG; BETA-PICTORIS; KECK SPECTRA; LITHIUM; VELOCITIES AB We have estimated the ages of eight late-type Vega-like stars by using standard age-dating methods for single late-type stars, e.g., location on the color-magnitude diagram, Li lambda 6708 absorption, Ca (II) H and K emission, Xray luminosity, and stellar kinematic population. With the exception of the very unusual pre-main-sequence star system HD 98800, all the late-type Vega-like stars are the same age as the Hyades cluster (600-800 Myr) or older. C1 Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Osservatorio Astrofis Arcetri, I-50125 Florence, Italy. RP Song, I (reprint author), Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. RI Barrado Navascues, David/C-1439-2017 OI Barrado Navascues, David/0000-0002-5971-9242 NR 28 TC 52 Z9 52 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2000 VL 533 IS 1 BP L41 EP L44 DI 10.1086/312597 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309VN UT WOS:000086790100011 ER PT J AU Backwell, PRY Christy, JH Telford, SR Jennions, MD Passmore, NI AF Backwell, PRY Christy, JH Telford, SR Jennions, MD Passmore, NI TI Dishonest signalling in a fiddler crab SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE cheating; dishonesty; signalling ID HARRIS SPARROWS; UCA ANNULIPES; CRUSTACEA; HANDICAP; SIZE AB Animal communication theory predicts that low-frequency cheating should be common in generally honest signalling systems. However, perhaps because cheats are designed to go undetected, there are few examples of dishonest signals in natural populations. Here we present what we believe is the first example of a dishonest signal which is used commonly by males to attract mates and fight sexual rivals. After losing their large claw, male fiddler crabs (Uca annulipes) grow a new one which has less mass, is a less effective weapon and costs less to use in signalling than an equivalent-length claw of the original form. Males with original claws do not differentially fight males with regenerated claws even though they are likely to win. Regenerated claws effectively bluff fighting ability and deter potential opponents before they fight. During mate searching, females do not discriminate against males with low-mass, regenerated claws, indicating that they are deceived as to the true costs males pay to produce sexual signals. Up to 44% of males in natural populations have regenerated claws: a level unanticipated by current signalling theory. The apparent rarity of cheating may be an artefact of the usual difficulty of detecting cheats and dishonesty may be quite common. C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Witwatersrand, Dept Zool, ZA-2050 Johannesburg, South Africa. RP Backwell, PRY (reprint author), Smithsonian Trop Res Inst, POB 2072, Balboa, Panama. EM backwelp@naos.si.edu RI Jennions, Michael/C-7560-2009; Backwell, Patricia/C-8883-2009 OI Jennions, Michael/0000-0001-9221-2788; NR 21 TC 109 Z9 113 U1 14 U2 88 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD APR 7 PY 2000 VL 267 IS 1444 BP 719 EP 724 PG 6 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 303FA UT WOS:000086410300014 PM 10821619 ER PT J AU Jayawardhana, R AF Jayawardhana, R TI Astronomy - New stars on the block SO SCIENCE LA English DT Editorial Material ID T-TAURI STARS; HD-98800 C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Jayawardhana, R (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 23 TC 5 Z9 5 U1 0 U2 0 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 7 PY 2000 VL 288 IS 5463 BP 64 EP 65 DI 10.1126/science.288.5463.64 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 302VT UT WOS:000086387700029 ER PT J AU Lemaitre, R Collette, BB AF Lemaitre, R Collette, BB TI Austin Beatty Williams (17 October 1919-27 October 1999). Biographical summary SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Biographical-Item AB The professional career and aspects of the life of Austin Beatty Williams (17 October 1919-27 October 1999), Systematic Zoologist for the Systematics Laboratory of the U.S. National Marine Fisheries, are summarized. Included is a bibliography with the 118 papers published by Williams, and a list of all the new names he proposed along with the holotype repository and catalogue number of species and subspecies. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Smithsonian Inst, Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. RP Lemaitre, R (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 1 EP 12 PG 12 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500001 ER PT J AU Williams, AB Vargas, R AF Williams, AB Vargas, R TI A new species of mud shrimp, Upogebia cortesi, from Pacific Costa Rica (Decapoda : Thalassinidea : Upogebiidae) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB Upogebia cortesi, a new species of mud shrimp from the Pacific side of Costa Rica is described and illustrated. The type series was dredged parallel to shore in water of 30-40 m depth. The species shares lack of a strong proximal mesioventral spine on the merus of the second pereopod with several members of the genus from the western hemisphere; moreover, the species stands alone in having spineless articles on pereopods 1-5 except for fingers of the chelae. The rostrum has no ventral spines. Similarities between this and related species are emphasized in a partial abridgment of the key to upogebiid species in the eastern Pacific. C1 Smithsonian Inst, Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. Univ Costa Rica, Escuela Biol, Museu Zool, San Jose 2060, Costa Rica. RP Williams, AB (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. NR 5 TC 0 Z9 3 U1 1 U2 1 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 13 EP 16 PG 4 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500002 ER PT J AU Manning, RB Galil, B AF Manning, RB Galil, B TI A new genus of pinnotherid crab from the Indian Ocean (Crustacea : Decapoda : Brachyura) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB Abyssotheres, new genus, is recognized for Pinnotheres abyssicola Alcock & Anderson, 1899, known from a single female taken in a bivalve shell from a depth of 787 m off Travancore, India. In this new genus the dactyli of walking legs 1 and 2 are longer than those of walking legs 3 and 4. This is the eighth genus of pinnotherids that shares a two-segmented palp on the third maxilliped. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Israel Oceanog & Limnol Res Ltd, IL-31080 Haifa, Israel. RP Manning, RB (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 14 TC 2 Z9 3 U1 0 U2 0 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 66 EP 69 PG 4 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500009 ER PT J AU Heard, R Manning, RB AF Heard, R Manning, RB TI A new genus and species of ghost shrimp from Tobago, West Indies (Crustacea : Decapoda : Callianassidae) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB The new genus Pseudobiffarius is the seventh genus of Callianassinae recognized from the Americas. This monotypic genus is based on its type species from Tobago, West Indies, Pseudobiffarius caesari, new species. It differs from all members of the subfamily in having a very short, stout upper flagellum on the A1 peduncle. C1 Gulf Coast Res Lab, Ocean Springs, MS 39564 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Heard, R (reprint author), Gulf Coast Res Lab, E Beach Rd, Ocean Springs, MS 39564 USA. NR 8 TC 8 Z9 9 U1 0 U2 0 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 70 EP 76 PG 7 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500010 ER PT J AU Ferrari, FD Markhaseva, EL AF Ferrari, FD Markhaseva, EL TI Griceus buskeyi, a new genus and species of calanoid copepod (Crustacea) from benthopelagic waters off Hawaii SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article ID RIDGEWAYIA-KLAUSRUETZLERI AB The new genus and species of deep-sea, benthopelagic calanoid copepod, Griceus buskeyi, differs from other calanoid copepods in the following derived character states: dorsal interlocking extensions of abdominal somites; antenna 2, mandible, and maxilla 1 originate posterior to the labrum and paragnaths; coral endite of the mandible outside of the labral-paragnathal envelope; praecoxal and coral endites of maxilla 1 unarmed; praecoxal endites of maxilla 2 unarmed; endopod of maxilliped with four articulating segments. Two setae on middle endopodal segment of swimming legs 3 and 4 suggests the new genus and species belongs to the superfamily Augaptiloidea. A mandibular endopod which is reduced in size to a small unarmed lobe and absence of an endopod on maxilla 1 suggests an affinity with the arietellid genus Paraugaptilus Wolfenden. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Russian Acad Sci, Inst Zool, St Petersburg 199034, Russia. RP Ferrari, FD (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 23 TC 3 Z9 4 U1 0 U2 0 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 77 EP 87 PG 11 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500011 ER PT J AU Petit, RE Harasewych, MG AF Petit, RE Harasewych, MG TI Additions to the cancellariid (Mollusca : Neogastropoda) fauna of South Africa SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB Four new species of Cancellariidae are described from the continental shelf and upper continental slope off eastern South Africa. Admetula afra is distinguished from all congeners by its combination of small adult size (<11 mm), rounded shoulder, evenly reticulate sculpture, and distinct varix at the juncture of protoconch and teleoconch. Trigonostoma kilburni differs from all other Trigonostoma in its distinctive shell outline, unornamented peripheral keel, rounded rather than tabulate shoulder, and very narrow umbilicus. Nipponaphera wallacei differs from N. paucicostata (Sowerby, 1894), its geographically closest congener from the Arabian Sea area, in being umbilicate and in having a more rounded shoulder, and more numerous and finer spiral cords. Its frequent association with the turbinid Bolma andersoni suggests that it may be an ectoparasite of this species. Zeadmete verheckeni is most similar to Zeadmete subantarctica Powell, 1933, from off New Zealand, from which it can be distinguished by its lower spire and weaker surface sculpture. Among the South African taxa, Z. verheckeni most closely resembles "Cancellaria" eutrios Barnard, 1959, from which it is easily distinguished by its tabulate shoulder and lower spire. The geographic and bathymetric ranges of Admetula epula Petit & Harasewych, 1991, a species previously known only from "ex pisces" material, have been expanded based on live-collected specimens. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Petit, RE (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 12 TC 4 Z9 4 U1 0 U2 0 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 145 EP 154 PG 10 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500017 ER PT J AU Marinoni, L Mathis, WN AF Marinoni, L Mathis, WN TI A cladistic analysis of Sciomyzidae Fallen (Diptera) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article ID IMMATURE STAGES AB A preliminary cladistic analysis of adult characters is presented that illustrates the phylogenetic relationships among the genera of the family Sciomyzidae. The monophyly of Sciomyzidae is based primarily on larval characters: the habit of malacophagy and the presence of a serrate ventral arch that articulates with the lower margin of the mouth hooks. A reduction in the number of spermathecae, from three to two, is also likely to be a synapomorphy for Sciomyzidae. The analysis was done using Hennig86, and 37 morphological characters were arranged among 50 genera. After using successive weighting, six cladograms were produced, and from these a consensus cladogram was obtained. The subfamilies Salticellinae and Sciomyzinae are confirmed to be monophyletic, as are the tribes Sciomyzini and Tetanocerini. Eutrichomelina Steyskal, which has been placed in the tribe Sciomyzini, is transferred to the tribe Tetanocerini. The genus Antichaeta Haliday is confirmed to be in the tribe Tetanocerini. Illustrations of antenna and male terminalia are presented. C1 Univ Fed Parana, Dept Zool, BR-81531990 Curitiba, Parana, Brazil. Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Marinoni, L (reprint author), Univ Fed Parana, Dept Zool, Caixa Postal 19020, BR-81531990 Curitiba, Parana, Brazil. RI Marinoni, Luciane /C-5720-2013 NR 73 TC 16 Z9 16 U1 0 U2 1 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X EI 1943-6327 J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 162 EP 209 PG 48 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500019 ER PT J AU Malabarba, LR Weitzman, SH AF Malabarba, LR Weitzman, SH TI A new genus and species of inseminating fish (Teleostei : Characidae : Cheirodontinae : Compsurini) from South America with uniquely derived caudal-fin dermal papillae SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article ID GLANDULOCAUDINAE AB Kolpotocheirodon theloura, a new genus and species of the cheirodontine tribe Compsurini, is described from the uppermost tributaries of the rio Sao Francisco and rio Parana in central Brazil. Males of the new species bear a caudal-fin organ formed by fin-ray hooks and hypertrophied elongate dermal flaps along the fin rays, mostly in the ventral lobe of the caudal fin. The largest flap, attached dorsally to the nineteenth principal caudal-fin ray (ventral principal fm ray of the ventral caudal-fin lobe), is bordered with a series of tabs, and extends dorsally over most of the flaps extending from caudal-fin rays 17 and 18. There are also a series of fleshy papillae distributed along the border of the remaining ventral caudal-fin ray flaps or along the fin rays just dorsal to the flap-bearing fm rays. These tabs and papillae are unknown in both other inseminating and all externally fertilizing characids and therefore are considered derived. The new species is referred to the Compsurini of the Cheirodontinae on the basis of a cladistic diagnosis of these taxa. The relationships of K. theloura with other inseminating compsurins bearing modified caudal fins are discussed. C1 Univ Fed Rio Grande Sul, Inst Biociencias, Dept Zool, BR-90046900 Porto Alegre, RS, Brazil. PUCRS, Museu Ciencias & Tecnol, BR-90619900 Porto Alegre, RS, Brazil. Smithsonian Inst, Dept Vertebrate Zool, Div Fishes, Washington, DC 20560 USA. RP Malabarba, LR (reprint author), Univ Fed Rio Grande Sul, Inst Biociencias, Dept Zool, Av Paulo Gama S-N, BR-90046900 Porto Alegre, RS, Brazil. RI Malabarba, Luiz/I-3225-2012 NR 34 TC 13 Z9 16 U1 0 U2 1 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 269 EP 283 PG 15 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500026 ER PT J AU Heyer, WR de Carvalho, CM AF Heyer, WR de Carvalho, CM TI Calls and calling behavior of the frog Leptodactylus natalensis (Amphibia : Anura : Leptodactylidae) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB Leptodactylus natalensis has a prolonged calling season, typically from May to September. Individuals occur in and call from the most forested patch of habitat an the campus of the Universidade Federal de Sergipe. Two kinds of calls were recorded and analyzed-advertisement and chirp calls. The function of the chirp call is unknown. The advertisement call has two carrier frequency bands, known to date for only two other species of Leptodactylus. The two carrier bands may correspond to different frequency tuning sensitivities in males and females, as females have slightly larger tympani than males, corresponding with their larger overall size. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. Univ Fed Sergipe, Dept Biol, BR-49100000 Sao Cristovao, Sergipe, Brazil. RP Heyer, WR (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. NR 8 TC 3 Z9 10 U1 0 U2 2 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 284 EP 290 PG 7 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500027 ER PT J AU Olson, SL AF Olson, SL TI Fossil Red-shouldered Hawk in the Bahamas: Calohierax quadratus Wetmore synonymized with Buteo lineatus (Gmelin) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB A supposedly extinct genus and species of hawk, Calohierax quadratus Wetmore, was originally described from a fragmentary tarsometatarsus from Quaternary deposits in Little Exuma Island in the Bahamas. This and a referred tibiotarsus from New Providence, Island, were later assigned to the extant genus Buteo, but their specific identity remained uncertain. A previously unstudied humerus from a cave deposit on New Providence Island, Bahamas, is here identified with the extant Red-shouldered Hawk, Buteo lineatus Gmelin, a species widespread in eastern North America and common in peninsular Florida but unknown in the Bahamas. The other fossils ate assigned to this species as well. Calohierax quadratus therefore becomes a synonym of Buteo lineatus, which species has retreated from the Bahamas in the late Quaternary for reasons that are unclear. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. RP Olson, SL (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. NR 9 TC 3 Z9 3 U1 0 U2 0 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 6 PY 2000 VL 113 IS 1 BP 298 EP 301 PG 4 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 303MK UT WOS:000086425500029 ER PT J AU Stine, JK AF Stine, JK TI Forged consensus: Science, technology. and economic policy in the United States, 1921-1953. SO AMERICAN HISTORICAL REVIEW LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Stine, JK (reprint author), Smithsonian Inst, Washington, DC 20560 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 2000 VL 105 IS 2 BP 562 EP 562 DI 10.2307/1571525 PG 1 WC History SC History GA 306LE UT WOS:000086597500073 ER PT J AU Schwarzbach, AE Ricklefs, RE AF Schwarzbach, AE Ricklefs, RE TI Systematic affinities of Rhizophoraceae and Anisophylleaceae, and intergeneric relationships within Rhizophoraceae, based on chloroplast DNA, nuclear ribosomal DNA, and morphology SO AMERICAN JOURNAL OF BOTANY LA English DT Article DE Anisophylleaceae; atpB-rbcL spacer; cpDNA; Erythroxylaceae; ITS; mangroves; nrDNA; rbcL; Rhizophoraceae; trnL-rrnF spacer; vivipary ID RBCL SEQUENCE DATA; PLASTID GENE RBCL; NUCLEOTIDE-SEQUENCES; PHYLOGENETIC-RELATIONSHIPS; FLOWERING PLANTS; SEED PLANTS; EVOLUTION; REGION; MYRTALES; CIRCUMSCRIPTION AB A cladistic analysis of sequences from the chloroplast gene rbcL. was used to determine the systematic affinities of Rhizophoraceae and Anisophylleaceae. This analysis rejects close relationships of Rhizophoraceae with Celastraceae or Elaeocarpaceae, suggested previously, and identifies Erythroxylaceae as sister group within the Malpighiales, supported by several morphological and anatomical characters. Our molecular results also indicate that Anisophylleaceae are nested within Cucurbitales. Although this placement is novel, this affinity is also well supported by shared morphological characters. Tribal and generic relationships within Rhizophoraceae are evaluated with a combination of six molecular data sets (rbcL, atpB-rbcL intergenic spacer, trnL-trnF intergenic spacer, ITS1, ITS2, and 5.8S) and a morphological data set. These relationships are compared with results from previous morphological cladistic analyses. Against the background of the molecular results, we briefly discuss the evolution of morphological characters traditionally used for tribal subdivision as well as characters presumably significant for adaptation to mangrove habitats, namely, aerial stilt roots and vivipary. C1 Univ Missouri, Dept Biol, St Louis, MO 63121 USA. Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. RP Schwarzbach, AE (reprint author), Indiana Univ, Dept Biol, Bloomington, IN 47405 USA. NR 88 TC 57 Z9 68 U1 2 U2 8 PU BOTANICAL SOC AMER INC PI COLUMBUS PA OHIO STATE UNIV-DEPT BOTANY 1735 NEIL AVE, COLUMBUS, OH 43210 USA SN 0002-9122 J9 AM J BOT JI Am. J. Bot. PD APR PY 2000 VL 87 IS 4 BP 547 EP 564 DI 10.2307/2656599 PG 18 WC Plant Sciences SC Plant Sciences GA 305ET UT WOS:000086527000012 PM 10766727 ER PT J AU Mulhern, DM AF Mulhern, DM TI Rib remodeling dynamics in a skeletal population from Kulubnarti, Nubia SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Article DE osteon; bone formation rate; activation frequency; effective age of adult compacta; Nubia ID MISSING OSTEONS; FORMATION RATES; BONE-FORMATION; ALGORITHM; PATTERNS; AGE AB Bone remodeling variables in the rib were analyzed for a skeletal population of medieval antiquity (ca. A.D. 550-1450) from Kulubnarti, in Sudanese Nubia. The skeletal remains are naturally mummified and in an excellent state of preservation. The study sample consists of thin sections from the ribs of 80 individuals, ranging in age from 15-50+ years. Ribs were examined using a standard microscope and image analysis software. Numbers of intact osteons, fragmentary osteons, forming osteons, and resorption spaces were counted, osteon and Haversian canal areas were measured, and several variables were calculated to assess morphometric and remodeling status in the rib. Variables calculated included mean annual activation frequency, mean bone formation rate, and net osteonal remodeling. Results indicate that age changes are consistent with those observed for other archaeological and modern samples. High numbers of resorption spaces in young males may reflect slower skeletal development in boys compared to girls. Comparisons of rib data with results of a previous study on patterns of femoral bone remodeling in the same population indicate that ribs have more osteons and higher bone formation rates compared to the femur. Also, sexual differences in osteon size observed in the femur were not observed in the rib. Activation frequency and bone formation rate are low in the Kulubnarti population compared to previously published data for a modern sample, a finding consistent with reported results from other archaeological samples. Genetic factors influencing the minimum effective strain setpoint and duration of skeletal maturation, in addition to repetitive high strains at Kulubnarti, may contribute to observed differences. (C) 2000 Wiley-Liss, Inc. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, Washington, DC 20560 USA. RP Mulhern, DM (reprint author), 5830 High Bluff Court, Burke, VA 22015 USA. EM Mulhern.Dawn@nmnh.si.edu NR 30 TC 23 Z9 23 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PD APR PY 2000 VL 111 IS 4 BP 519 EP 530 PG 12 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 299YX UT WOS:000086227000007 PM 10727970 ER PT J AU Parker, GG Brown, MJ AF Parker, GG Brown, MJ TI Forest canopy stratification - Is it useful? SO AMERICAN NATURALIST LA English DT Article DE forest; canopy; layer; stratification; stratum ID NORTHERN HARDWOOD FORESTS; RAIN-FOREST; TROPICAL FORESTS; SPECIES-DIVERSITY; WESTERN HEMLOCK; DOUGLAS-FIR; GROWTH; TEMPERATE; GAPS; SUCCESSION AB It has long been recognized that the forest canopy has a complex structure that is significant for environmental interactions, regeneration, growth, and biotic habitat. Not only is the structure variously complex, but also there are many ways to conceptualize that complexity. Yet the persistent theme when considering the structure of canopies continues to be that of stratification: whether structural units are arranged in layers above the ground. We examined the use of the terms "stratification," "layering," and others in connection with canopy structure and found they had various meanings (often only implied) that were difficult to reconcile and to measure. We applied the definitions to the structure of a single, well-studied canopy located in Virginia, U.S.A., and found they failed to define consistently and clearly the presence, number, or location of strata. Additionally, we found the concept had limitations related to scale dependence, point of reference, and spatial averaging. Thus, asserting that a forest is stratified or naming the number of layers generally provided no guide to its structure. We propose alternative ways of conceptualizing and studying the forest canopy that avoid most of the problems associated with stratification. Among these are direct measurement and mapping of structural and environmental variables that have clear potential connections with canopy Functions and viewing the distribution of structures or environmental conditions within the canopy as ecological gradients. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Synth Res & Anal, Portland, OR 97208 USA. RP Parker, GG (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. EM parker@serc.si.edu; LM@spiritone.com OI Parker, Geoffrey/0000-0001-7055-6491 NR 75 TC 53 Z9 59 U1 6 U2 24 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0003-0147 J9 AM NAT JI Am. Nat. PD APR PY 2000 VL 155 IS 4 BP 473 EP 484 DI 10.1086/303340 PG 12 WC Ecology; Evolutionary Biology SC Environmental Sciences & Ecology; Evolutionary Biology GA 308WR UT WOS:000086736300004 ER PT J AU Crosthwaite, LP Turner, JL Ho, PTP AF Crosthwaite, LP Turner, JL Ho, PTP TI Structure in the neutral hydrogen disk of the spiral galaxy IC 342 SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : individual (IC 342); galaxies : ISM; galaxies : spiral; galaxies : structure; ISM : HI ID H-II REGIONS; INTERSTELLAR-MEDIUM; SUPERNOVA-REMNANTS; STAR FORMATION; IC-342; SHELLS; M51; SUPERSHELLS; EVOLUTION; DISTANCES AB We present 38 " resolution Very Large Array 21 cm continuum and H I line emission observations of the spiral galaxy IC 342, at an adopted distance of 2 Mpc. Kinematic evidence exists for a m = 2 spiral density wave in the inner disk with a corotation radius located at 4 kpc and a possible four-arm pattern in the outer disk. On smaller scales, outside of the central depression in H I column density, H I is organized into a complex pattern of relatively short (similar to 2-5 kpc), interconnected, spiral arm segments. Numerous "holes" are distributed throughout the H I disk. By considering the effects of shear, structures that are not self-gravitating, such as holes and voids, cannot be long-term phenomena. The timescale, combined with the total energy required to evacuate holes, leads us to reject wind and supernovae origins for the large-scale pattern of H I holes in IC 342. Gravitational instabilities in the disk form on a timescale that is short compared with the rotation period of the disk. The pattern of H I spiral arm segments exists on a scale that is consistent with their being material arms that result from gravitational instabilities. The H I cavities are a natural remnant of the process. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Crosthwaite, LP (reprint author), Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. NR 46 TC 47 Z9 48 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 2000 VL 119 IS 4 BP 1720 EP 1736 DI 10.1086/301302 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304WY UT WOS:000086508100018 ER PT J AU Torres, G Stefanik, RP AF Torres, G Stefanik, RP TI The cessation of eclipses in SS Lacertae: The mystery solved SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : eclipsing; binaries : spectroscopic; stars : evolution; stars : fundamental parameters; stars : individual (SS Lacertae) ID OPEN CLUSTER NGC-7209; APSIDAL MOTION; SPECTROSCOPIC BINARIES; RADIAL-VELOCITIES; STELLAR MODELS; DI-HERCULIS; SYSTEMS; STARS; PHOTOMETRY; TODCOR AB The 14.4 day period eclipsing binary SS Lacertae in the open cluster NGC 7209 is unusual in that the eclipses stopped completely about the middle of this century, giving rise to considerable speculation as to the cause. Disruption of the binary through a collision with another member of the cluster and, more likely, gravitational perturbations from a third star in the system have been proposed to explain the phenomenon. We present here the results of our intensive radial velocity monitoring of the object, which show clearly that there is indeed a third star in the system in a slightly eccentric orbit with a period of about 679 days. We also reanalyze the historical light curves of SS Lac to determine the properties of the system early in the century. We discuss the implications of our findings in terms of changes in the inclination angle of the close pair. An analysis of available times of eclipse for SS Lac together with the new velocity information has also revealed apsidal motion in the system, (omega) over dot = 0.degrees 0137 cycle(-1), corresponding to an apsidal period of about 1000 yr. We argue that the third star is probably responsible for this effect also. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Torres, G (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 71 TC 18 Z9 20 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 2000 VL 119 IS 4 BP 1914 EP 1929 DI 10.1086/301290 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304WY UT WOS:000086508100032 ER PT J AU Torres, G Andersen, J Nordstrom, B Latham, DW AF Torres, G Andersen, J Nordstrom, B Latham, DW TI Absolute dimensions of eclipsing binaries. XXIII. The F-type system EI Cephei SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : eclipsing; binaries : spectroscopic; stars : evolution; stars : fundamental parameters; stars : individual (EI Cephei) ID SPECTROSCOPIC BINARIES; MAIN-SEQUENCE; STARS; CIRCULARIZATION; SYNCHRONIZATION; TEMPERATURES; EVOLUTION; MASSES; MODEL AB We report new radial velocity measurements made with the Harvard-Smithsonian Center for Astrophysics Digital Speedometers of the F-type double-lined eclipsing binary EI Cep (P = 8.4 days), in which the secondary is a metallic-line star. Using these and previous measurements from the literature, we redetermine the masses of the components to a precision of 0.4%, 4 to 5 times better than previously achieved. We also reanalyze UBV light curves for the system from the literature with modern methods to determine the radii and the effective temperatures. The resulting stellar parameters are M-A = 1.7716 +/- 0.0066 M-., M-B = 1.6801 +/- 0.0062 M-., R-A = 2.896 +/- 0.048 R-. R-B = 2.329 +/- 0.044 R-., T-eff(A), = 6750 +/- 100 K, and T-eff(B), = 6950 +/- 100 K. Further properties of the system are given in this paper: Both components are near the end oft heir main-sequence evolution, and a comparison of the observational results with theoretical evolutionary models gives excellent agreement with models using two somewhat different treatments of overshooting from the convective cores (but not with standard models). An age of 1.4 Gyr is derived for the roughly solar metallicity indicated by our low signal-to-noise ratio spectra. A precise spectroscopic determination of the metallicity of EI Cep would be very useful to place even tighter constraints on the models. The measured projected rotational velocities of the stars (13 and 17 km s(-1) for EI Cep A and B, respectively) are very close to, but not quite synchronized with, the orbital motion. This is in agreement with predictions from current tidal theories, which, however, also predict that orbital circularization has not yet occurred, although we detect no significant eccentricity. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Astron Observ, NBIfAFG, DK-2100 Copenhagen, Denmark. RP Torres, G (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 61 TC 15 Z9 16 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 2000 VL 119 IS 4 BP 1942 EP 1955 DI 10.1086/301305 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304WY UT WOS:000086508100034 ER PT J AU Ros, E Marcaide, JM Guirado, JC Sardon, E Shapiro, II AF Ros, E Marcaide, JM Guirado, JC Sardon, E Shapiro, II TI A GPS-based method to model the plasma effects in VLBI observations SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE plasmas; atmospheric effects; methods : observational; techniques : interferometric; astrometry ID GLOBAL POSITIONING SYSTEM; DIFFERENTIAL ASTROMETRY; ALGORITHM AB Global Positioning System (GPS) satellites broadcast at frequencies of 1,575.42 MHz (L1) and of 1,227.60 MHz (L2). The dispersive property of the ionosphere can be used to combine independent measurements at the two frequencies to estimate the total electron content (TEC) between a GPS receiver site and a broadcasting satellite. Such measurements, made at sites near to Very Long Baseline Interferometry (VLBI) sites, can be used to estimate the ionospheric contribution to VLBI observables. For our 1991.9 astrometric VLBI experiment in which we obtained group-delay observations in the 8.4 and 2.3 GHz bands simultaneously, we found that the GPS and VLBI determinations of the ionosphere delays agreed with root-mean-square differences below 0.15 ns for intercontinental baselines and 0.10 ns for continental ones. We also successfully applied the GPS-based procedure to reduce the ionospheric effect in phase delays used for high precision differenced astrometry at 8.4 GHz for this same experiment. C1 Univ Valencia, Dept Astron & Astrofis, E-46100 Burjassot, Valencia, Spain. Max Planck Inst Radioastron, D-53121 Bonn, Germany. Deutsch Forsch Anstalt Luft & Raumfahrt EV, Fernerkundungstn Neustrelitz, D-17235 Neustrelitz, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ros, E (reprint author), Univ Valencia, Dept Astron & Astrofis, E-46100 Burjassot, Valencia, Spain. EM ros@mpifr-bonn.mpg.de NR 11 TC 23 Z9 23 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2000 VL 356 IS 1 BP 357 EP 362 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 311DJ UT WOS:000086869300051 ER PT J AU Churazov, E Forman, W Jones, C Bohringer, H AF Churazov, E Forman, W Jones, C Bohringer, H TI Asymmetric, arc minute scale structures around NGC 1275 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : clusters : individual : A426; galaxies : cooling flows; galaxies : individual : NGC 1275; galaxies : ISM; X-rays : galaxies ID RAY-EMITTING GAS; PERSEUS CLUSTER; COOLING FLOWS; INTRACLUSTER MEDIUM; RADIO; NGC-1275; GALAXIES; MODELS; ROSAT AB ROSAT HRI observations show complicated substructure in the X-ray surface brightness within similar to 5 arcminutes around NGC 1275 - the dominant galaxy of the Perseus cluster. The typical amplitude of the variations is of the order of 30% of the azimuthally averaged surface brightness at a given distance from NGC 1275. We argue that this substructure could be related to the activity of NGC 1275 in the past. Bubbles of relativistic plasma, inflated by jets, being forced to rise by buoyancy forces, mix with the ambient intracluster medium (ICM), and then spread. Overall evolution of the bubble may resemble the evolution of a hot bubble during a powerful atmospheric explosion. From a comparison of the time scale of the bubble inflation to the rise time of the bubbles and from the observed size of the radio lobes which displace the thermal gas, the energy release in the relativistic plasma by the active nucleus of NGC 1275 can be inferred. Approximate modeling implies a nuclear power output of the order of 10(45) erg s(-1) averaged over the last similar to 3 10(7) years. This is comparable with the energy radiated in X-rays during the same epoch. Detailed measurements of the morphology of the X-ray structure, the temperature and abundance distributions with Chandra and XMM may test this hypothesis. C1 Max Planck Inst Astrophys, D-85740 Garching, Germany. Moscow Space Res Inst, Moscow 117810, Russia. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. RP Churazov, E (reprint author), Max Planck Inst Astrophys, Karl Schwarzschild Str 1, D-85740 Garching, Germany. RI Churazov, Eugene/A-7783-2013 NR 24 TC 142 Z9 142 U1 0 U2 3 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2000 VL 356 IS 3 BP 788 EP 794 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 321GA UT WOS:000087446700008 ER PT J AU Kurtz, MJ Eichhorn, G Accomazzi, A Grant, CS Murray, SS Watson, JM AF Kurtz, MJ Eichhorn, G Accomazzi, A Grant, CS Murray, SS Watson, JM TI The NASA Astrophysics Data System: Overview SO ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES LA English DT Article DE methods : data analysis; astronomical databases : miscellaneous; publications : bibliography; sociology of astronomy ID ASTRONOMICAL LITERATURE; INFORMATION; LIBRARY; VOIDS; WEB AB The NASA Astrophysics Data System Abstract Service has become a kev component of astronomical research. It provides bibliographic information daily, or near daily, to a majority of astronomical researchers worldwide. We describe the history of the development of the system and its current status. Urania (Boyce 1996). and the ADS role in the emerging electronic astronomical data environment are discussed. Astronomy is unique in that it already has a fully functional data resource, where several of the most important data sources exist on-line and inter-operate nearly seamlessly. The ADS and the Strasbourg Data Center (CDS; Geneva et al. 2000) form the core of this resource. We show several examples of how to use the ADS. and we show how ADS use has: increased as a function of time. Currently it is still increasing exponentially; with a doubling time for number of queries of 17 months. Using the ADS logs we make the first detailed model of how scientific journals are read as a function of time since publication. We find four distinct components. We directly compare the readership rate with the citation rate for scientific articles as a funct ion of age. Citations generally follow reads, but there are some differences. The main journals of astronomy have differences in the ways they are read and cited. We discuss these from a number of different aspects. The impact of the ADS on astronomy can be calculated after making some simple assumptions. We find that the ADS increases the efficiency of astronomical reseal ch by 333 Full Time Equivalent (2000 hour) research years per year, and that the value of the early development of the ADS for astronomy, compared with waiting for mature technologies to be adopted, is 2332 FTE research years. A full technical description of the ADS is in three companion articles: Eichhorn et al. (2000), Accomazzi et al. (2000), and Grant et al. (2000). The ADS is available at http://adsabs.harvard.edu/. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM kurtz@cfa.harvard.edu RI KURTZ, Michael /B-3890-2009; OI Eichhorn, Guenther/0000-0002-3032-1978; Grant, Carolyn/0000-0003-4424-7366; Kurtz, Michael/0000-0002-6949-0090; Accomazzi, Alberto/0000-0002-4110-3511 NR 78 TC 72 Z9 72 U1 1 U2 3 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0365-0138 J9 ASTRON ASTROPHYS SUP JI Astron. Astrophys. Suppl. Ser. PD APR PY 2000 VL 143 IS 1 BP 41 EP 59 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 305NX UT WOS:000086548100005 ER PT J AU Eichhorn, G Kurtz, MJ Accomazzi, A Grant, CS Murray, SS AF Eichhorn, G Kurtz, MJ Accomazzi, A Grant, CS Murray, SS TI The NASA Astrophysics Data System: The search engine and its user interface SO ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES LA English DT Article DE methods : data analysis; databases : misc; publications, bibliography ID ACCESS METHODS AB The ADS Abstract and Article Services pros ide access to the astronomical literature through the World Wide Web (WWW). The forms based user interface provides access to sophisticated searching capabilities that allow our users to find references in the fields of Astronomy, Physics/Geophysics, and astronomical Instrumentation and Engineering. The returned information includes links to other an-line information sources, creating an extensive astronomical digital library. Otter interfaces to the ADS databases provide direct access to the ADS data to allow developers of other data systems to integrate our data into their system. The search engine is a custom-built software system that is specifically tailored to search astronomical references. It includes an extensive synonym list that contains discipline specific knowledge about search term equivalences. Search request logs show the usage pattern of the various search system capabilities. Access logs show the world-wide distribution of ADS users. The ADS can be accessed at: http://adswww.harvard.edu. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Eichhorn, G (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI KURTZ, Michael /B-3890-2009; OI Eichhorn, Guenther/0000-0002-3032-1978; Grant, Carolyn/0000-0003-4424-7366; Kurtz, Michael/0000-0002-6949-0090; Accomazzi, Alberto/0000-0002-4110-3511 NR 23 TC 19 Z9 19 U1 1 U2 2 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 0365-0138 J9 ASTRON ASTROPHYS SUP JI Astron. Astrophys. Suppl. Ser. PD APR PY 2000 VL 143 IS 1 BP 61 EP 83 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 305NX UT WOS:000086548100006 ER PT J AU Accomazzi, A Eichhorn, G Kurtz, MJ Grant, CS Murray, SS AF Accomazzi, A Eichhorn, G Kurtz, MJ Grant, CS Murray, SS TI The NASA Astrophysics Data System: Architecture SO ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES LA English DT Article DE methods : data analysis; astronomical data bases : miscellaneous; publications : bibliography ID INFORMATION-RETRIEVAL; TEXT RETRIEVAL; THESAURUS AB The powerful discovery capabilities available in the ADS bibliographic services are possible thanks to the design of a flexible search and retrieval system based on a relational database model. Bibliographic records are stared as a corpus of structured documents containing fielded data and metadata, while discipline-specific knowledge is segregated in a set of files independent of the bibliographic data itself. This ancillary information is used by the database management software to compile field-specific index files used by the ADS search engine to resolve user queries into lists of relevant documents. The creation and management of links to both internal and external resources associated with each bibliography in the database is made possible by representing them as a set of document properties and their attributes. The resolution of links available from different locations has been generalized to allow its control through a site- and user-specific preference database. To improve global access to the ADS data holdings, a number of mirror sites have been created by cloning the database contents and software on a variety of hardware and software platforms. The procedures used to create and manage the database and its mirrors have been written as a set of scripts that can be run in either an interactive or unsupervised fashion. The modular approach we followed in software development has allowed a high degree of freedom in prototyping and customization, malting our system rich of features and yet simple enough to be easily modified on a day-to-day basis, We conclude discussing the impact that new datasets, technologies and collaborations is expected to have on the ADS and its possible role in an integrated environment of networked resources in astronomy. The ADS can be accessed at: http://adswww.harvard.edu. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Accomazzi, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI KURTZ, Michael /B-3890-2009; OI Eichhorn, Guenther/0000-0002-3032-1978; Grant, Carolyn/0000-0003-4424-7366; Kurtz, Michael/0000-0002-6949-0090; Accomazzi, Alberto/0000-0002-4110-3511 NR 57 TC 18 Z9 18 U1 0 U2 2 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 0365-0138 J9 ASTRON ASTROPHYS SUP JI Astron. Astrophys. Suppl. Ser. PD APR PY 2000 VL 143 IS 1 BP 85 EP 109 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 305NX UT WOS:000086548100007 ER PT J AU Grant, CS Accomazzi, A Eichhorn, G Kurtz, MJ Murray, SS AF Grant, CS Accomazzi, A Eichhorn, G Kurtz, MJ Murray, SS TI The NASA Astrophysics Data System: Data holdings SO ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES LA English DT Article DE methods : data analysis; astronomical bibliography AB Since its inception in 1993, the ADS Abstract Service has became an indispensable research tool for astronomers and astrophysicists worldwide. In those seven years, much effort has been directed toward improving both the quantity and the quality of references ill the database. From the original database of approximately 160 000 astronomy abstracts, our dataset has grown almost tenfold to approximately 1.5 million references covering astronomy, astrophysics, planetary sciences, physics, optics, and engineering. We collect and standardize data. from approximately 200 journals and present the resulting information in a uniform. coherent manner. With the cooperation of journal publishers worldwide, we have been able to place scans of full journal articles on-line back to the first volumes of many astronomical journals, and we are able to link to current version of articles, abstracts, and datasets for essentially all of the current astronomy literature. The trend toward electronic publishing in the field, the use of electronic submission of abstracts for journal articles and conference proceedings, and the increasingly prominent use of the World Wide Web to disseminate information have enabled the ADS to build a database unparalleled in other disciplines. The ADS can be accessed at: http://adswww.harvard.edu. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Grant, CS (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI KURTZ, Michael /B-3890-2009; OI Eichhorn, Guenther/0000-0002-3032-1978; Grant, Carolyn/0000-0003-4424-7366; Kurtz, Michael/0000-0002-6949-0090; Accomazzi, Alberto/0000-0002-4110-3511 NR 28 TC 22 Z9 22 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 0365-0138 J9 ASTRON ASTROPHYS SUP JI Astron. Astrophys. Suppl. Ser. PD APR PY 2000 VL 143 IS 1 BP 111 EP 135 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 305NX UT WOS:000086548100008 ER PT J AU Nevalainen, J Markevitch, M Forman, W AF Nevalainen, J Markevitch, M Forman, W TI The cluster M-T relation from temperature profiles observed with ASCA and ROSAT SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; dark matter; galaxies : clusters : general intergalactic medium; X-rays : galaxies ID X-RAY; DARK-MATTER; INTRACLUSTER MEDIUM; MASS DETERMINATION; GALAXY CLUSTERS; ENRICHMENT; ABUNDANCES; EVOLUTION AB We calibrate the galaxy cluster mass-temperature (M-T) relation using the temperature profiles of intracluster gas observed with ASCA (for hot clusters) and ROSAT (for cool groups). Our sample consists of apparently relaxed clusters for which the total masses are derived, assuming hydrostatic equilibrium. The sample provides data on cluster X-ray emission-weighted cooling-flow-corrected temperatures and total masses up to r(1000). The resulting M-T scaling in the 1-10 keV temperature range is M-1000 = (1.23 +/- 0.20) 10(15) h(50)(-1) M.(< T >(z=0)/10 keV)(1.79 +/- 0.14) with 90% confidence errors, or significantly (99.99% confidence) steeper than the self-similar relation M proportional to T-3/2. For any given temperature, our measured mass values are significantly smaller compared to the simulation results of Evrard, Metzler, & Navarro that are frequently used for mass-temperature scaling. The higher temperature subsample (kT greater than or equal to 4 keV) is consistent with M proportional to T-3/2, allowing the possibility that the self-similar scaling breaks down at low temperatures, perhaps due to heating by supernovae that is more important for low-temperature groups and galaxies, as suggested by earlier works. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Nevalainen, J (reprint author), Univ Helsinki Observ, Helsinki, Finland. OI Forman, William/0000-0002-9478-1682 NR 34 TC 90 Z9 90 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2000 VL 532 IS 2 BP 694 EP 699 DI 10.1086/308608 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304DX UT WOS:000086468500002 ER PT J AU Vilas-Boas, JWS Myers, PC Fuller, GA AF Vilas-Boas, JWS Myers, PC Fuller, GA TI Dense cores of dark clouds. XII. (CO)-C-13 and (CO)-O-18 in Lupus, Corona Australis, Vela, and Scorpius SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; ISM : molecules; stars : pre-main-sequence; submillimeter ID HERBIG-HARO OBJECTS; YOUNG STELLAR OBJECTS; CO OBSERVATIONS; STAR-FORMATION; CHAMELEON; ASSOCIATION; ADJACENT; REGIONS; COUNTS; NEBULA AB More than 110 dense condensations of the dark clouds in Lupus, Corona Australis, Norma, Vela, and Scorpius were observed in the (CO)-C-13 and (CO)-O-18 (J = 1-0) transitions. The condensations of dark clouds with high star formation activity like the Ophiuchus, Taurus, and Cepheus have average (CO)-O-18 and H-2 column densities of 1.8 x 10(15) and 1.1 x 10(22) cm(-2). If We take the average size of the condensations to be 0.2 pc, a condensation must have average H-2 volumetric densities greater than or equal to 2 x 10(4) cm(-3) in order to ea good candidate to form stars. The four Lupus filaments have similar radial velocities and velocity dispersions, suggesting that they originated from the same parental cloud. Among these filaments, Lupus 1 is unique in having recent star formation activity, despite the high number of T Tauri stars observed toward the others. Lupus 1 also shows a complex velocity gradient along its main axis. The distribution of radial velocities of the condensations observed toward Scorpius are in good agreement with the hypothesis that they are in a region with expansion velocity smaller than or equal to 18 km s(-1). The Corona Australis cloud has velocity gradients ranging from -0.5 km s(-1) pc(-1) at one extreme to 0.1 km s(-1) pc(-1) at the other. C1 Inst Presbiteriano Mackenzie, CRAAE INPE, Ctr Aplicacoes Espacias, BR-01302000 Sao Paulo, Brazil. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Manchester, Inst Sci & Technol, Natl Radio Astron Observ, Manchester M60 1QD, Lancs, England. Univ Manchester, Inst Sci & Technol, Dept Phys, Manchester M60 1QD, Lancs, England. RP Vilas-Boas, JWS (reprint author), Inst Presbiteriano Mackenzie, CRAAE INPE, Ctr Aplicacoes Espacias, R Consolacao 89, BR-01302000 Sao Paulo, Brazil. NR 54 TC 27 Z9 28 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2000 VL 532 IS 2 BP 1038 EP 1050 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304DX UT WOS:000086468500022 ER PT J AU Esin, AA Kuulkers, E McClintock, JE Narayan, R AF Esin, AA Kuulkers, E McClintock, JE Narayan, R TI Optical light curves of the black hole binaries GRS 1124-68 and A0620-00 in outburst: The importance of irradiation SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; plasmas; radiation mechanisms : thermal ID X-RAY BINARIES; NOVA MUSCAE 1991; ADVECTION-DOMINATED ACCRETION; MASS; DISKS; NOVA-MUSCAE-1991; TRANSIENTS; EVOLUTION; MODEL; IUE AB We test whether the model proposed by Esin ct al. to explain X-ray observations of the black hole soft X-ray transient GRS 1124-68 in outburst can also explain the optical light curves of a similar object, A0620-00. We show that to reproduce the observed X-ray to optical flux ratio in A0620-00, we need to assume X-ray irradiation of the outer disk that is significantly in excess of what is expected for a standard planar disk. With enhanced irradiation, the Esin et al. model can reproduce the optical evolution of A0620-00 in outburst very well. Though we find that optical observations of GRS 1124-68 also imply enhanced X-ray heating of the outer disk, the irradiation appears to be a factor of similar to 3 weaker in this system than in A0620-00. This is surprising, since GRS 1124-68 has a larger disk. We speculate that enhanced irradiation may be due to disk warping, and that the degree of warping differs between the two binaries. C1 CALTECH, Pasadena, CA 91125 USA. Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA. Space Res Org Netherlands, NL-3584 CA Utrecht, Netherlands. Univ Utrecht, Astron Inst, NL-3507 TA Utrecht, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP CALTECH, 130-33, Pasadena, CA 91125 USA. EM aidle@tapir.caltech.edu; E.Kuulkers@sron.nl; jmcclintock@cfa.harvard.edu; rnarayan@cfa.harvard.edu NR 70 TC 37 Z9 37 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2000 VL 532 IS 2 BP 1069 EP 1077 DI 10.1086/308615 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304DX UT WOS:000086468500024 ER PT J AU Moore, CB Rutledge, RE Fox, DW Guerriero, RA Lewin, WHG Fender, R van Paradijs, J AF Moore, CB Rutledge, RE Fox, DW Guerriero, RA Lewin, WHG Fender, R van Paradijs, J TI Identification of a likely radio counterpart to the rapid burster SO ASTROPHYSICAL JOURNAL LA English DT Article DE radiation mechanisms : nonthermal; radio continuum : stars; stars : individual (MXB 1730-335); X-rays : stars ID RAY TIMING EXPLORER; GLOBULAR-CLUSTERS; GRO J1744-28; GRS-1915+105; ARRAY; PERFORMANCE; DISCOVERY; BEHAVIOR; MASS; GHZ AB We have identified a likely radio counterpart to the low-mass X-ray binary MXB 1730-335 (the Rapid Burster). The counterpart has shown 8.4 GHz radio on/off behavior correlated with the X-ray on/off behavior as observed by the RXTE/ASM during six VLA observations. The probability of an unrelated, randomly varying background source duplicating this behavior is 1%-3% depending on the correlation timescale. The location of the radio source is R.A. 17(h)33(m)24.(s)61, decl. -33 degrees 23'19." 8 (J2000), +/-0." 1. We do not detect 8.4 GHz radio emission coincident with type II (accretion-driven) X-ray bursts. The ratio of radio to X-ray emission during such bursts is constrained to be below the ratio observed during X-ray-persistent emission at the 2.9 sigma level. Synchrotron bubble models of the radio emission can provide a reasonable fit to the full data set, collected over several outbursts, assuming that the radio evolution is the same from outburst to outburst but given the physical constraints the emission is more likely to be due to similar to 1 hr radio flares such as have been observed from the X-ray binary GRS 1915+105. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Space Radiat Lab, Pasadena, CA 91125 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. US Mil Acad, Dept Phys, West Point, NY 10996 USA. Univ Amsterdam, Astron Inst Anton Pannekoek, Ctr High Energy Astrophys, NL-1098 SJ Amsterdam, Netherlands. Univ Alabama, Huntsville, AL 35899 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 78, Cambridge, MA 02138 USA. EM cmoore@cfa.harvard.edu; rutledge@srl.caltech.edu; derekfox@space.mit.edu; hr6958@exmail.usma.army.mil; lewin@space.mit.edu; rpf@astro.uva.nl; jvp@astro.uva.nl NR 50 TC 14 Z9 14 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 1 PY 2000 VL 532 IS 2 BP 1181 EP 1191 DI 10.1086/308589 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304DX UT WOS:000086468500034 ER PT J AU Cranmer, SR AF Cranmer, SR TI Ion cyclotron wave dissipation in the solar corona: The summed effect of more than 2000 ion species SO ASTROPHYSICAL JOURNAL LA English DT Review DE plasmas; radiative transfer; solar wind; Sun : corona; turbulence; waves ID INTERPLANETARY ALFVENIC FLUCTUATIONS; DRIVEN STELLAR WINDS; HEATING MECHANISMS; RESONANT ACCELERATION; TRANSITION REGION; POWER SPECTRUM; 2-FLUID MODEL; MINOR IONS; HEAVY-IONS; PLASMAS AB In this paper the dissipation of ion cyclotron resonant Alfven waves in the extended solar corona is examined in detail. For the first time, the wave damping arising from more than 2000 low-abundance ion species is taken into account. Useful approximations for the computation of coronal ionization equilibria for elements heavier than nickel are presented. Also, the Sobolev approximation from the theory of hot-star winds is applied to the resonant wave dissipation in the solar wind, and the surprisingly effective damping ability of "minor" ions is explained in simple terms. High-frequency (10-10,000 Hz) waves propagating up from the base of the corona are damped significantly when they resonate with ions having charge-to-mass ratios of about 0.1, and negligible wave power would then be available to resonate with higher charge-to-mass ratio ions at larger heights. This result confirms preliminary suggestions from earlier work that the waves that heat and accelerate the high-speed solar wind must be generated throughout the extended corona. The competition and eventual equilibrium between wave damping and wave replenishment may explain observed differences in coronal O VI and Mg X emission line widths. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM scranmer@cfa.harvard.edu NR 130 TC 128 Z9 128 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2000 VL 532 IS 2 BP 1197 EP 1208 DI 10.1086/308620 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304DX UT WOS:000086468500036 ER PT J AU Turner, JL Beck, SC Ho, PTP AF Turner, JL Beck, SC Ho, PTP TI The radio supernebula in NGC 5253 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : dwarf; galaxies : individual (NGC 5253); galaxies : peculiar; galaxies : starburst; galaxies : star clusters; radio continuum : galaxies ID H-II REGIONS; STAR-FORMATION; GALAXY NGC-5253; SPECTROSCOPY; STARBURSTS AB We present 1.3 cm and 2 cm subarcsecond resolution VLA images of the dwarf galaxy NGC 5253. Within the central starburst, we detect high-brightness [T-b(2 cm) similar to 100-12,000 K] radio continuum sources. These appear to be very dense, "compact" H II regions. The dominant radio source is a nebula similar to 1-2 pc in size, requiring several thousand O stars within the volume to maintain its ionization. This nebula has no obvious optical counterpart. The number of ionizing photons we find for this cluster is nearly 2 orders of magnitude larger than indicated by Hat fluxes, and the deduced stellar content accounts for a significant fraction of the total infrared luminosity of the galaxy. This cluster is a strong candidate for a globular cluster in the process of formation, perhaps the youngest globular cluster known. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Tel Aviv Univ, Dept Phys & Astron, Ramat Aviv, Israel. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Turner, JL (reprint author), Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. NR 22 TC 101 Z9 101 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2000 VL 532 IS 2 BP L109 EP L112 DI 10.1086/312586 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304DZ UT WOS:000086468700007 ER PT J AU Ghavamian, P Hartigan, P Raymond, JC AF Ghavamian, P Hartigan, P Raymond, JC TI Using Balmer line shapes to diagnose physical conditions in collisionless shock waves SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article; Proceedings Paper CT 2nd International Workshop on Laboratory Astrophysics with Intense Lasers CY MAR 19-21, 1998 CL TUCSON, ARIZONA C1 Rice Univ, Dept Space Phys & Astron, Houston, TX 77005 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ghavamian, P (reprint author), Rice Univ, Dept Space Phys & Astron, MS 108,6100 S Main St, Houston, TX 77005 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD APR PY 2000 VL 127 IS 2 BP 323 EP 323 DI 10.1086/313343 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 337FN UT WOS:000088346900019 ER PT J AU Rasmussen, PC Round, PD Dickinson, EC Rozendaal, FG AF Rasmussen, PC Round, PD Dickinson, EC Rozendaal, FG TI A new bush-warbler (Sylviidae, Bradypterus) from Taiwan SO AUK LA English DT Article AB A bush-warbler of the genus Bradypterus, known from the mountains of Taiwan since 1917, has never been formally named as a distinct taxon. Songs of the Taiwan population differ strikingly from those of its Asian congeners in being much clearer, sweeter, more piercing, and in having a very different structure of elements. Several subtle but consistent morphological differences exist between specimens from Taiwan and all named taxa, principally in bill size and shape, plumage color and reduced variability, pattern of undertail coverts, and wing formula. Therefore, the Taiwan population is best treated as a new species. C1 Smithsonian Inst, Div Birds, Washington, DC 20560 USA. Michigan State Univ, E Lansing, MI 48824 USA. Mahidol Univ, Fac Sci, Ctr Conservat Biol, Bangkok 10400, Thailand. Trust Oriental Ornithol, Eastbourne BN20 7JG, England. RP Rasmussen, PC (reprint author), Smithsonian Inst, Div Birds, Washington, DC 20560 USA. NR 15 TC 5 Z9 9 U1 0 U2 2 PU AMER ORNITHOLOGISTS UNION PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0004-8038 J9 AUK JI AUK PD APR PY 2000 VL 117 IS 2 BP 279 EP 289 DI 10.1642/0004-8038(2000)117[0279:ANBWSB]2.0.CO;2 PG 11 WC Ornithology SC Zoology GA 306XJ UT WOS:000086623700001 ER PT J AU Robinson, TR Robinson, WD Edwards, EC AF Robinson, TR Robinson, WD Edwards, EC TI Breeding ecology and nest-site selection of Song Wrens in central Panama SO AUK LA English DT Article ID SUCCESS; BIRDS AB We describe nest-site selection and report measures of breeding productivity from a population of Song Wrens (Cyphorhinus phaencephalus) in central Panama. We studied 31 pairs from 1995 to 1998 and collected data on nest predation from 1996 to 1998. Song Wrens are year-round residents that build breeding nests for reproduction and dormitory nests for roosting. Twenty-five of 50 Song Wren breeding nests produced fledglings (dairy nest survival rate = 0.968). Song Wrens usually (78%) placed their breeding nests in ant-defended acacias (Acacia melanoceras). However, nests placed in acacias did not experience lower rates of nest predation than nests placed in sites not defended by ants. The population-wide breeding season was seven months long, but individual pairs often bred within a span of only 2.5 months. Modal clutch size was two (n = 42), but the frequency of three-egg clutches was high (greater than or equal to 27%). Pairs that lost eggs or chicks renested more quickly than pairs that fledged young and attempted a second brood. Observed annual production of young was 1.4 fledglings per pair. Compared with other wrens, Song Wrens had a much longer breeding season and longer intervals between broods. The annual productivity of Song Wrens was the lowest recorded for any wren, which may have been due to smaller clutch sizes, long intervals between broods, and the correspondingly low number of nesting attempts per pair per year. C1 Univ Illinois, Dept Ecol Ethol & Evolut, Champaign, IL 61820 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Robinson, TR (reprint author), Auburn Univ, Dept Zool & Wildlife Sci, 331 Funchess Hall, Auburn, AL 36849 USA. NR 33 TC 21 Z9 23 U1 1 U2 11 PU AMER ORNITHOLOGISTS UNION PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0004-8038 J9 AUK JI AUK PD APR PY 2000 VL 117 IS 2 BP 345 EP 354 DI 10.1642/0004-8038(2000)117[0345:BEANSS]2.0.CO;2 PG 10 WC Ornithology SC Zoology GA 306XJ UT WOS:000086623700007 ER PT J AU Slikas, B Jones, IB Derrickson, SR Fleischer, RC AF Slikas, B Jones, IB Derrickson, SR Fleischer, RC TI Phylogenetic relationships of Micronesian white-eyes based on mitochondrial sequence data SO AUK LA English DT Article ID CYTOCHROME-B; EVOLUTION; ORDER; GENE AB Using mitochondrial sequence data, we estimated phylogenetic relationships and genetic divergence among selected species of white-eyes (Zosteropidae). We focused on taxa endemic to islands in Micronesia, specifically Zosterops conspicillatus, Z. semperi, Z. hypolais, Rukia oleaginea, and Cleptornis marchei. We also included in our data set five additional species of Zosterops from the Indo-Australian region and three species from Africa, as well as additional passerine outgroups. Our mitochondrial sequence data revealed substantial genetic divergence (5.7 to 7.3%) among Z. conspicillatus, Z. semperi, and Z. hypolais, three taxa that formerly were treated as a single species. In addition, a sequence divergence of 6.5 +/- SE of 1.7% was found between the population of Z. conspicillatus from Rota and ''conspecific" populations on Guam, Tinian, and Saipan. The distinctiveness of the Rota population suggests that this taxon should be recognized as a distinct species, a result that bears on the conservation of this population because it has been declining dramatically in recent years. All optimal trees based on analysis of the mitochondrial sequence data place Rukia oleaginea within the genus Zosterops. In all optimal trees, Cleptornis marchei positions as the sister taxon to a clade including all other zosteropids included in this study. The trees based on our data strongly contradict the traditional classification of Cleptornis as a honeyeater (family Meliphagidae). Our data cannot resolve with any confidence the sister relationships of the insular endemic white-eyes, although the optimal trees suggest multiple colonizations of Micronesia by more than one white-eye lineage. C1 Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. RP Slikas, B (reprint author), Smithsonian Inst, Natl Zool Pk, 3001 Connecticut Ave NW, Washington, DC 20008 USA. RI Slikas, Beth/E-7275-2013 NR 23 TC 46 Z9 48 U1 0 U2 8 PU AMER ORNITHOLOGISTS UNION PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0004-8038 J9 AUK JI AUK PD APR PY 2000 VL 117 IS 2 BP 355 EP 365 DI 10.1642/0004-8038(2000)117[0355:PROMWE]2.0.CO;2 PG 11 WC Ornithology SC Zoology GA 306XJ UT WOS:000086623700008 ER PT J AU Sattler, GD Braun, MJ AF Sattler, GD Braun, MJ TI Morphometric variation as an indicator of genetic interactions between Black-capped and Carolina chickadees at a contact zone in the Appalachian mountains SO AUK LA English DT Article ID PARUS-ATRICAPILLUS; HYBRID ZONES; REPRODUCTIVE ISOLATION; MITOCHONDRIAL-DNA; BIRDS; HYBRIDIZATION; INTROGRESSION; EVOLUTIONARY; SPECIATION; FRAGMENTS AB We Studied hybridization and introgression between Black-capped (Poecile atricapillus) and Carolina (P. carolinensis) chickadees along two transects in the Appalachians using four genetic markers and multivariate analysis of morphology. Genetic data revealed that at least 58% of the birds in the center of each transect were of mixed ancestry and that recombinant genotypes predominated among hybrids, demonstrating that hybridization is frequent and that many hybrids are fertile. Genetic dines generally were steep and coincident in position, but introgression was evident well beyond the range interface. Introgression was higher at the one autosomal locus surveyed than in mitochondrial DNA or in two sex-linked markers, suggesting that the hybrid zone is a conduit for gene flow between the two forms at some loci. On a broad scare, morphometric variation was concordant with genetic variation. Clines in morphological Variation based on principal components (PC) scores were steep and coincident with genetic dines. Also, a strong correlation within a population between PC scores and an individual's genetic makeup suggested that a large amount of morphological variation was genetically determined. However, morphological analysis indicated that hybrids were uncommon on one transect, whereas genetic data clearly showed that they were common on both. In addition, patterns of morphological variation were equivocal regarding introgression across the hybrid zone. Thus, genetic data provided a complementary and more detailed assessment of hybridization, largely due to the discrete nature of genetic variation. Genetic markers are useful in understanding hybridization and introgression, but diagnostic markers may underestimate average gene now if selection against hybrids maintains steep dines at diagnostic loci. To gain a clearer picture of the genome-wide effects of hybridization, a much larger number of loci must be assayed, including non-diagnostic ones. C1 Smithsonian Inst, Natl Museum Nat Hist, Lab Mol Systemat, Washington, DC 20560 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. RP Sattler, GD (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Lab Mol Systemat, MRC 534, Washington, DC 20560 USA. NR 70 TC 33 Z9 34 U1 0 U2 4 PU AMER ORNITHOLOGISTS UNION PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0004-8038 J9 AUK JI AUK PD APR PY 2000 VL 117 IS 2 BP 427 EP 444 DI 10.1642/0004-8038(2000)117[0427:MVAAIO]2.0.CO;2 PG 18 WC Ornithology SC Zoology GA 306XJ UT WOS:000086623700015 ER PT J AU Kleiman, DG Reading, RP Miller, BJ Clark, TW Scott, M Robinson, J Wallace, RL Cabin, RJ Felleman, F AF Kleiman, DG Reading, RP Miller, BJ Clark, TW Scott, M Robinson, J Wallace, RL Cabin, RJ Felleman, F TI Improving the evaluation of conservation programs SO CONSERVATION BIOLOGY LA English DT Article ID ENDANGERED SPECIES RECOVERY; MANAGEMENT; REINTRODUCTION; PLANS; ACT AB The evaluation of conservation programs is rare but increasingly important in improving their effectiveness. Regular evaluations of conservation programs and the implementation of recommendations resulting from such assessments are infrequent because of resistance by participants and lack of funding. Evaluations may be internal or external, depending on the purpose of the review and how broadly it is focused. We strongly recommend external peer review of long-term complex conservation programs every 5 years, supported by more frequent (annual) internal reviews. Criteria for success must encompass both biological and social measures and include learning and the application of new knowledge to management. Evaluations must also go beyond monitoring to assess the value of the program. We emphasize the need to include the organization and function of a conservation program (the process) in any evaluation in addition to substantive criteria for success, which usually involve biological measures (numbers). A dysfunctional program organization and process can as effectively cripple a conservation effort as can a major biological catastrophe. We provide examples of different types of conservation program evaluations, including moderated workshops and case-study analysis, and provide advice on the logistics and organization of the review, emphasizing the importance of the evaluation process itself to a successful outcome. One important aspect of an evaluation is having an individual with leadership ability and considerable expertise to organize the format and oversee the review process itself. Second, it is essential at the outset to ensure agreement among the program participants and the review committee on the goals and objectives of the conservation program, what is to be evaluated, and the criteria for defining success. Finally, the best evaluations are inclusive and involve all participants and stakeholders. C1 Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. Denver Zool Fdn, Dept Conservat Biol, Denver, CO 80218 USA. Yale Univ, Sch Forestry & Environm Studies, New Haven, CT 06511 USA. Univ Idaho, Dept Fish & Wildlife, US Geol Survey, Moscow, ID 83844 USA. Wildlife Conservat Soc, Bronx, NY 10460 USA. US Forest Serv, USDA, Hilo, HI 96720 USA. Conservat Consultants Inc, Seattle, WA 98117 USA. RP Kleiman, DG (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. EM dkleiman@nzp.si.edu NR 63 TC 62 Z9 68 U1 2 U2 41 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD APR PY 2000 VL 14 IS 2 BP 356 EP 365 DI 10.1046/j.1523-1739.2000.98553.x PG 10 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 300WD UT WOS:000086275800004 ER PT J AU Canterbury, GE Martin, TE Petit, DR Petit, LJ Bradford, DF AF Canterbury, GE Martin, TE Petit, DR Petit, LJ Bradford, DF TI Bird communities and habitat as ecological indicators of forest condition in regional monitoring SO CONSERVATION BIOLOGY LA English DT Article ID BIOLOGICAL INTEGRITY; RESOURCE MANAGEMENT; BIOTIC INTEGRITY; NEST PREDATION; POPULATIONS; GUILDS; SITES; TOOL AB Ecological indicators for long-term monitoring programs are needed to detect and assess changing environmental conditions. We developed and tested community-level environmental indicators for monitoring forest bird populations and associated habitat. We surveyed 197 sampling plots in loblolly-shortleaf pine forests, spanning an area from Georgia to Virginia (U.S.A.) and representing a gradient in levels of anthropogenic disturbance. Ninety of these plots were randomly selected from a sampling grid, permitting quantitative assessment of cumulative distribution functions for bird community and habitat parameters. Species were independently classified into habitat assemblages indicating birds typical of disturbed habitat (e.g., shrubland, forest edge) and undisturbed habitat (mature forest). Relative abundances of these assemblages were used to form a bird community index-similar to the index of biotic integrity applied to aquatic systems-showing the effects of habitat disturbance on forest bird communities. Bird communities on the majority of the sample area (52-75%, 90% confidence interval) were dominated by disturbance-tolerant species. Sites dominated by mature-forest species were comparatively uncommon. Habitat assemblages appeared to be particularly useful tools for environmental monitoring; individual species abundance was positively correlated with assemblage species richness, and assemblage members showed consistent responses to variations in disturbance level. To a lesser extent, component species of nesting guilds showed this pattern of cohesive responses, but those of foraging guilds did not. We also developed a habitat index based on habitat variables that predicted bird community index values. Habitat and bird community indices were strongly correlated in an independent validation dataset, suggesting that the habitat index can provide a reliable predictor of bird community status. The two indices may be used in combination, with the bird community index providing a direct measure of the status of the bird community and the habitat index providing a basis on which to separate changes in the bird community into local habitat effects versus other factors (e.g., landscape level effects, changes on wintering grounds). C1 Univ Montana, Montana Cooperat Wildlife Res Unit, Missoula, MT 59812 USA. US Fish & Wildlife Serv, Arlington, VA 22203 USA. Smithsonian Inst, Natl Zool Pk, Smithsonian Migratory Bird Ctr, Washington, DC 20008 USA. US EPA, Environm Monitoring Syst Lab, Las Vegas, NV 89193 USA. RP Canterbury, GE (reprint author), US Fish & Wildlife Serv, 2800 Cottage Way,Suite W2605, Sacramento, CA 95825 USA. RI Martin, Thomas/F-6016-2011 OI Martin, Thomas/0000-0002-4028-4867 NR 42 TC 107 Z9 126 U1 7 U2 63 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD APR PY 2000 VL 14 IS 2 BP 544 EP 558 DI 10.1046/j.1523-1739.2000.98235.x PG 15 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 300WD UT WOS:000086275800022 ER PT J AU Benvenuti, D Messana, G Schotte, M AF Benvenuti, D Messana, G Schotte, M TI On a new species of Oxinasphaera (Isopoda, Sphaeromatidae) from Somali and Yemeni coasts, western Indian Ocean SO CRUSTACEANA LA English DT Article AB The genus Oxinasphaera Bruce, 1997, distributed throughout the Indo-West Pacific region, is composed of twenty-four named and a few unnamed species. Oxinasphaera penteumbonata n. sp. is here described from specimens from the Yemeni coast of the Arabian peninsula and from the Indian Ocean coast of Somalia. The species is characterized by five distinct, acute spikes on the epistome. A comparison is made with other species of the genus present in the Indian Ocean. The key to the world's species of the genus is modified to host the new species. C1 CNR, Ctr Studio Faunist & Ecol Trop, I-50125 Florence, Italy. Natl Museum Nat Hist, Smithsonian Inst, Washington, DC 20560 USA. RP Benvenuti, D (reprint author), CNR, Ctr Studio Faunist & Ecol Trop, Via Romana 17, I-50125 Florence, Italy. RI messana, giuseppe/A-4080-2009; OI messana, giuseppe/0000-0002-2048-0078 NR 25 TC 2 Z9 2 U1 0 U2 1 PU BRILL ACADEMIC PUBLISHERS PI LEIDEN PA PLANTIJNSTRAAT 2, P O BOX 9000, 2300 PA LEIDEN, NETHERLANDS SN 0011-216X J9 CRUSTACEANA JI Crustaceana PD APR PY 2000 VL 73 BP 407 EP 415 DI 10.1163/156854000504499 PN 4 PG 9 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 320LT UT WOS:000087403200003 ER PT J AU Correll, DL Jordan, TE Weller, DE AF Correll, DL Jordan, TE Weller, DE TI Dissolved silicate dynamics of the Rhode River watershed and estuary SO ESTUARIES LA English DT Article ID CHESAPEAKE BAY; BIOGEOCHEMICAL CYCLE; NUTRIENTS; PHYTOPLANKTON; EUTROPHICATION; CHEMISTRY; GEOCHEMISTRY; ENVIRONMENT; PHOSPHORUS; DISCHARGES AB We continuously measured dissolved silicate concentrations and fluxes discharged from various Rhode River subwatersheds for a period of 14 yr from 1984 to 1998 and for 15 mo in 1971-1972. We also measured dissolved silicate concentrations along a transect from the head of the tide in Rhode River estuary to Chesapeake Bay. The average concentration of dissolved silicate discharged from the Rhode River watershed was 10.8 mg Si l (1). There were consistent and significant differences in silicate concentrations discharged over time and space among subwatersheds. Mean annual silicate flux from the watershed was 26.6 kg Si ha(-1) and 93% of this occurred during the winter and spring seasons. There were large interannual variations in silicate flux, due primarily to differences in precipitation and water discharge, rather than silicate concentration. Land use had little or no effect on silicate flux from various subwatersheds. Silicate concentrations discharged from a subset of subwatersheds in 1995-1996 were 25% to 35% lower than in a period with similar precipitation in 1971-1972. Mean annual concentrations of silicate discharged from nine subwatersheds have been declining about 1.5% yr(-1) or by 0.21-0.26 mg Si l(-1) yr(-1) over the last 25 r. Despite high average silicate fluxes from the watershed, at times the Rhode River estuary developed low dissolved silicate concentrations, which could have been limiting to the growth of diatoms. Examples were in the spring after a winter with low watershed discharge (as low as 0.019 mg Si l(-1) in 1995) and after protracted drought (as low as 0.041 mg Si l (1) in 1993). C1 Smithsonian Inst, Smithsonian Environm Res Ctr, Edgewater, MD 21040 USA. RP Correll, DL (reprint author), 3970 Timucua Point N, Crystal River, FL 34428 USA. OI Weller, Donald/0000-0002-7629-5437 NR 51 TC 8 Z9 10 U1 1 U2 5 PU ESTUARINE RES FEDERATION PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 USA SN 0160-8347 J9 ESTUARIES JI Estuaries PD APR PY 2000 VL 23 IS 2 BP 188 EP 198 DI 10.2307/1352826 PG 11 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 324MT UT WOS:000087626500003 ER PT J AU Greenfield, MD Rand, AS AF Greenfield, MD Rand, AS TI Frogs have rules: Selective attention algorithms regulate chorusing in Physalaemus Pustulosus (Leptodactylidae) SO ETHOLOGY LA English DT Article ID SEXUAL SELECTION; SIGNAL INTERACTIONS; FEMALE PHONOTAXIS; EVOLUTION; MECHANISMS; PHONORESPONSE; ORTHOPTERA; INSECTS; HEARING; CHOICE AB In various acoustic insects and frogs, females preferentially orient towards the leading of two or more males' advertisement signals that occur closely in time. Such preferences in receivers have apparently selected for timing mechanisms whereby male signallers actively refrain from calling immediately following the onset of a neighbour's call and thereby increase their production of leading calls. However, indiscriminate application of this inhibitory mechanism to all neighbours might severely reduce a male's calling rate, particularly in high density. Consequently, mechanisms of selective attention to only a subset of signalling neighbours are expected. Female Tungara frogs (Physalaemus pustulosus) exhibit strong preferences for leading male calls, and males refrain from calling immediately following a neighbour. Four-loudspeaker playback experiments demonstrated that males do selectively apply this inhibitory mechanism to only a subset of close signalling neighbours. Selective attention is regulated by a combination of sliding threshold and fixed number rules: (i) Attend to the loudest (nearest) conspecific neighbour and those additional ones whose calls are within 6-8 dB of the loudest one; (ii) attend to only two neighbours in total when the calls are weak or the second one is much farther than the first; (iii) attend to three neighbours when the calls are loud or all neighbours are approximately equidistant. The means by which such plasticity may be achieved and its potential adaptiveness are discussed. C1 Univ Kansas, Dept Entomol, Lawrence, KS 66045 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Greenfield, MD (reprint author), Univ Kansas, Dept Entomol, Lawrence, KS 66045 USA. OI Greenfield, Michael/0000-0003-1935-3423 NR 34 TC 55 Z9 59 U1 0 U2 6 PU BLACKWELL WISSENSCHAFTS-VERLAG GMBH PI BERLIN PA KURFURSTENDAMM 57, D-10707 BERLIN, GERMANY SN 0179-1613 J9 ETHOLOGY JI Ethology PD APR PY 2000 VL 106 IS 4 BP 331 EP 347 DI 10.1046/j.1439-0310.2000.00525.x PG 17 WC Psychology, Biological; Behavioral Sciences; Zoology SC Psychology; Behavioral Sciences; Zoology GA 309RQ UT WOS:000086783400004 ER PT J AU Krupnick, GA Avila, G Brown, KM Stephenson, AG AF Krupnick, GA Avila, G Brown, KM Stephenson, AG TI Effects of herbivory on internal ethylene production and sex expression in Cucurbita texana SO FUNCTIONAL ECOLOGY LA English DT Article DE insect damage; monoecious; phytohormones; reproductive biology; sink-source interactions ID MECHANISTIC MODEL; FLOWERING PLANTS; CUCUMIS-SATIVUS; WOUND RESPONSE; TOMATO PLANTS; SENESCENCE; GENDER; STRESS; LEAVES; DAMAGE AB 1. Field-grown Cucurbita texana was used in a study to determine if stress ethylene from damaged leaves promotes changes in sex expression. 2. Internal ethylene concentrations were experimentally enhanced by inserting an ethylene-filled syringe into the hollow chamber of an internode seven nodes from the growing tip of a branch. Branches enhanced with ethylene produced significantly more pistillate buds than control branches and experienced greater bud abortion later in floral development. 3. The timing and magnitude of Diabrotica beetle leaf damage was simulated using a paper-hole puncher (15% removed from all leaves). Simulated herbivory was applied to new growth every 3 days throughout the growing season. 4. Endogenous ethylene concentrations recovered from the internode adjacent to the growing tip were significantly greater in damaged plants than undamaged plants 1 day after damage to new growth during the second and third week of the experiment, and 2 days after damage during the fourth and fifth week. By the sixth week, no significant differences were evident. 5. Damaged plants produced fewer pistillate buds than undamaged plants, indicating that stress ethylene from simulated herbivory does not induce femaleness. A second messenger that suppresses pistillate bud production may be produced during damage. C1 Penn State Univ, Dept Biol, Mueller Lab 208, University Pk, PA 16802 USA. RP Krupnick, GA (reprint author), Smithsonian Trop Res Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RI Avila Sakar, German/G-4243-2011; OI Krupnick, Gary/0000-0002-1357-4826 NR 47 TC 16 Z9 16 U1 1 U2 9 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0269-8463 J9 FUNCT ECOL JI Funct. Ecol. PD APR PY 2000 VL 14 IS 2 BP 215 EP 225 DI 10.1046/j.1365-2435.2000.00413.x PG 11 WC Ecology SC Environmental Sciences & Ecology GA 328HY UT WOS:000087845800008 ER PT J AU Huelsenbeck, JP Larget, B Swofford, D AF Huelsenbeck, JP Larget, B Swofford, D TI A compound Poisson process for relaxing the molecular clock SO GENETICS LA English DT Article ID MITOCHONDRIAL-DNA; NUCLEOTIDE SUBSTITUTION; DIVERGENCE TIMES; MARKOV-CHAINS; EVOLUTION; SEQUENCES; RATES; CONSTANCY; SITES AB The molecular clock hypothesis remains an important conceptual and analytical tool in evolutionary biology despite the repeated observation that the clock hypothesis does not perfectly explain observed DNA sequence variation. We introduce a parametric model that relaxes the molecular crock by allowing rates to vary across lineages according to a compound Poisson process. Events of substitution rate change are placed onto a phylogenetic tree according to a Poisson process. When an event of substitution rate change occurs, the current rate of substitution is modified by a gamma-distributed random variable. Parameters of the model can be estimated using Bayesian inference. We use Markov chain Monte Carlo integration to evaluate the posterior probability distribution because the posterior probability involves high dimensional integrals and summations. Specifically, we use the Metropolis-Hastings-Green algorithm with 11 different move types to evaluate the posterior distribution. We demonstrate the method by analyzing a complete mtDNA sequence data set from 23 mammals. The model presented here has several potential advantages over other models that have been proposed to relax the clock because it is parametric and does not assume that rates change only at speciation events. This model should prove useful for estimating divergence times when substitution rates vary across lineages. C1 Univ Rochester, Dept Biol, Rochester, NY 14627 USA. Duquesne Univ, Dept Math & Comp Sci, Pittsburgh, PA 15282 USA. Smithsonian Museum Support Ctr, Lab Mol Systemat, Suitland, MD 20746 USA. RP Huelsenbeck, JP (reprint author), Univ Rochester, Dept Biol, 601 Elmwood Ave, Rochester, NY 14627 USA. EM johnh@brahms.biology.rochester.edu RI Huelsenbeck, John/C-6398-2013 NR 31 TC 208 Z9 208 U1 2 U2 7 PU GENETICS SOC AM PI BETHESDA PA 9650 ROCKVILLE AVE, BETHESDA, MD 20814 USA SN 0016-6731 J9 GENETICS JI Genetics PD APR PY 2000 VL 154 IS 4 BP 1879 EP 1892 PG 14 WC Genetics & Heredity SC Genetics & Heredity GA 304NU UT WOS:000086491000037 PM 10747076 ER PT J AU Stanley, DJ Hait, AK AF Stanley, DJ Hait, AK TI Deltas, radiocarbon dating, and measurements of sediment storage and subsidence SO GEOLOGY LA English DT Article DE deltaic sedimentation; Nile delta; Ganges-Brahmaputra delta; radiocarbon dates; sediment storage ID SEA-LEVEL RISE; AMAZON RIVER; NILE DELTA; BRAZIL; PEATS AB In Holocene marine deltaic sequences there is no simple relationship between radiocarbon age and depth of sampling, The Nile and Ganges-Brahmaputra deltas show remarkably similar radiocarbon age-depth relationships: (1) most radiocarbon dates, by conventional and accelerator mass spectrometric (AMS) analyses, are older (some by 4000 yr) than reasonably expected; (2) dates are commonly inverted (i.e., older upcore); and (3) sample dates at delta surfaces commonly exceed 2000 yr B.P. These anomalous age-depth phenomena are in part a response to reservoir effects, introduction of old carbon, and, emphasized herein, influence of sediment storage and remobilization that prevail in fluvial and delta plains. In fluvial systems, sediment generally is not transported in a single episode from its original source area to the sea. Rather, material transported from upland reaches and river valley to coast is subject to a repeated series of depositional, burial, and erosional events induced by episodic flooding, overbank sedimentation, and channel migration. Because sediment is likely to be temporarily stored in the delta plain, it is difficult to determine the time of a sediment's final deposition and burial at a delta site. A successful strategy requires use of several independent dating methods, including AMS analyses of in situ basal peats and fossils and where possible, archaeological evaluation of associated artifacts that are in place, Accurate dates are needed for reliable measurement of rates of delta plain aggradation and land subsidence, information to help implement effective coastal protection measures. C1 Smithsonian Inst, NHNH E206, Dept Paleobiol, Washington, DC 20560 USA. Ctr Study Man & Environm, Calcutta, W Bengal, India. RP Stanley, DJ (reprint author), Smithsonian Inst, NHNH E206, Dept Paleobiol, Washington, DC 20560 USA. NR 34 TC 42 Z9 44 U1 3 U2 13 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD APR PY 2000 VL 28 IS 4 BP 295 EP 298 PG 4 WC Geology SC Geology GA 300AC UT WOS:000086229800002 ER PT J AU Zimbelman, JR AF Zimbelman, JR TI Non-active dunes in the Acheron Fossae region of Mars between the Viking and Mars Global Surveyor eras SO GEOPHYSICAL RESEARCH LETTERS LA English DT Editorial Material ID FEATURES; MISSION; SURFACE; CAMERA; SAND AB Comparison of a high resolution Viking image (422B10; 8 m/pixel) with a Mars Orbiter Camera image (SP2-502/06; 5.6 m/pixel) of dunes in the Acheron Fossae region of Mars (38 degrees N, 135 degrees W) reveals that the dunes moved <1 pixel during a span of almost 21 Earth years. Very shallow illumination in the MOC image indicates the dunes are <1.5 m high. The images indicate that any movement of these Martian dunes is <0.4 m/yr, a rate that is less than the documented movement of comparable dunes on Earth by a factor of up to 200. The Acheron Fossae dunes occur within a region of low thermal inertia, indicating that the dunes may be stabilized by a pervasive dust cover. Alternatively, the saltation threshold was not exceeded significantly at this location in more than 20 years. C1 Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. RP Zimbelman, JR (reprint author), Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, MRC 315, Washington, DC 20560 USA. NR 32 TC 37 Z9 38 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 APR 1 PY 2000 VL 27 IS 7 BP 1069 EP 1072 DI 10.1029/1999GL008399 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 299XV UT WOS:000086224500043 ER PT J AU Schortemeyer, M Dijkstra, P Johnson, DW Drake, BG AF Schortemeyer, M Dijkstra, P Johnson, DW Drake, BG TI Effects of elevated atmospheric CO2 concentration on C and N pools and rhizosphere processes in a Florida scrub oak community SO GLOBAL CHANGE BIOLOGY LA English DT Article DE elevated CO2; microbial activity; phyllosphere; Quercus spp.; rhizosphere; soil microbes ID CARBON-DIOXIDE ENRICHMENT; MICROBIAL BIOMASS-C; SOIL CARBON; PERENNIAL RYEGRASS; PLANT-RESPONSES; LOLIUM-PERENNE; WHITE CLOVER; NITROGEN; EXTRACTION; ECOSYSTEM AB The effect of elevated atmospheric CO2 concentration (C-a) on soil carbon and nitrogen accumulation and soil microbial biomass and activity in a native Florida scrub oak community was studied. The plant community, dominated by Quercus myrtifolia Willd. and Q. geminata Small, was exposed for 2 years to elevated C-a in open-top chambers. Buried subsoil bags were retrieved after 1 year of exposure to elevated C-a. In addition, soil cores were taken twice from the chambers within two weeks in July 1998 (the first after a long dry spell and the second after 25 mm of rainfall) and divided into rhizosphere and bulk soil. Soil organic matter accumulation (excluding roots) into the buried subsoil bags was lower in elevated than in ambient C-a. Concentrations of soluble carbon and ninhydrin-reactive nitrogen (N-ninh) in the rhizosphere soil were reduced by elevated C-a for the first sampling date and unaffected for the second sampling date. Microbial activity, measured as fluorescein diacetate (FDA) hydrolysis, decreased in elevated C-a for the first sampling date. Microbial biomass carbon and nitrogen in the bulk soil were unaffected by elevated C-a. There was no effect of elevated C-a on bacterial numbers in the rhizosphere. C1 Australian Natl Univ, Res Sch Biol Sci, Environm Biol Grp, Canberra, ACT 2601, Australia. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Univ Nevada, Desert Res Inst, Ctr Biol Sci, Reno, NV 89506 USA. RP Schortemeyer, M (reprint author), Univ Western Australia, Fac Agr, Nedlands, WA 6907, Australia. NR 40 TC 22 Z9 27 U1 2 U2 14 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 1354-1013 J9 GLOB CHANGE BIOL JI Glob. Change Biol. PD APR PY 2000 VL 6 IS 4 BP 383 EP 391 DI 10.1046/j.1365-2486.2000.00317.x PG 9 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 320VD UT WOS:000087420300002 ER PT J AU Kidwell, PA AF Kidwell, PA TI The adding machine fraternity at St. Louis: Creating a center of invention, 1880-1920 SO IEEE ANNALS OF THE HISTORY OF COMPUTING LA English DT Article AB Between 1880 and 1920, several inventors in St. Louis, Missouri, made pioneering contributions to the development of commercial adding machines. Inventions of Frank S. Baldwin, William S. Burroughs, the brothers William W. and Hubert H. Hopkins, and their associates did much to make mechanical arithmetic commonplace in U.S. business. C1 Smithsonian Inst, Natl Museum Amer Hist, Div Informat Technol & Soc, Washington, DC 20560 USA. RP Kidwell, PA (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Div Informat Technol & Soc, Washington, DC 20560 USA. NR 54 TC 6 Z9 6 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 2000 VL 22 IS 2 BP 4 EP 21 DI 10.1109/85.841133 PG 18 WC Computer Science, Theory & Methods; History & Philosophy Of Science SC Computer Science; History & Philosophy of Science GA 304QJ UT WOS:000086494700002 ER PT J AU Kawamura, J Blundell, R Tong, CYE Papa, DC Hunter, TR Paine, SN Patt, F Gol'tsman, G Cherednichenko, S Voronov, B Gershenzon, E AF Kawamura, J Blundell, R Tong, CYE Papa, DC Hunter, TR Paine, SN Patt, F Gol'tsman, G Cherednichenko, S Voronov, B Gershenzon, E TI Superconductive hot-electron-bolometer mixer receiver for 800-GHz operation SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE submillimeter-wave mixers; superconducting devices ID LOW-NOISE; TERAHERTZ FREQUENCIES; WAVELENGTHS; BANDWIDTH; THZ AB In this paper, we describe a superconductive hot-electron-bolometer mixer receiver designed to operate in the partially transmissive 350-mu m atmospheric window. The receiver employs an NbN thin-film microbridge as the mixer element, in which the main cooling mechanism of the hot electrons is through electron-phonon interaction. At a local-oscillator frequency of 808 GHz, the measured double-sideband receiver noise temperature is T-RX = 970 K, across a 1-GHz intermediate-frequency bandwidth centered at 1.8 GHz, We have measured the linearity of the receiver and the amount of local-oscillator power incident on the mixer for optimal operation, which is P-LO approximate to 1 mu W. This receiver was used in making observations as a facility instrument at the Heinrich Hertz Telescope, Mt, Graham, AZ, during the 1998-1999 winter observing season. C1 CALTECH, Pasadena, CA 91125 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Submillimeter Telescope Observ, Tucson, AZ 85721 USA. Moscow State Pedag Univ, Moscow 119435, Russia. RP Kawamura, J (reprint author), CALTECH, Pasadena, CA 91125 USA. RI Cherednichenko, Sergey/E-9889-2011; OI Cherednichenko, Sergey/0000-0002-5397-8024; Tong, Edward/0000-0002-7736-4203; Paine, Scott/0000-0003-4622-5857; Hunter, Todd/0000-0001-6492-0090 NR 23 TC 16 Z9 16 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 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD APR PY 2000 VL 48 IS 4 BP 683 EP 689 DI 10.1109/22.841960 PN 2 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 310FN UT WOS:000086816000010 ER PT J AU Hau, M Wikelski, M Wingfield, JC AF Hau, M Wikelski, M Wingfield, JC TI Visual and nutritional food cues fine-tune timing of reproduction in a neotropical rainforest bird SO JOURNAL OF EXPERIMENTAL ZOOLOGY LA English DT Article ID OPPORTUNISTIC BREEDER; LOXIA-CURVIROSTRA; RESIDENT BIRDS; NEST PREDATION; CENTRAL PANAMA; RED CROSSBILL; FOREST BIRDS; ANNUAL CYCLE; SEASONALITY; INTEGRATION AB Food may act as a proximate factor in the regulation of avian seasonal breeding. Food cues could provide particularly important seasonal information to birds living in variable tropical environments, but this has not yet been tested. Spotted antbirds (Hylophylax n. naevioides) inhabiting a humid forest in central Panama (9 degrees N) Likely use changes in the tropical photoperiod to time reproduction on a long-term, seasonal basis. We predicted that these insectivorous birds also adjust reproduction to short-term cues such as food availability because the onset of the rainy season and the resulting increase in insect abundance varies considerably between years. To test this prediction, prior to their breeding season (when they had half-maximal gonads), we either exposed captive male spotted antbirds to an ad libitum standard diet only or added live crickets to this diet. Males that received live crickets significantly increased gonad sizes within 3 weeks over controls on the standard diet. Moreover, in six additional experiments cricket availability always increased song rate, usually within a few days. The stimulatory effect of live crickets on song activity may function independent of nutritional aspects: Freshly killed crickets, providing similar nutritional content as live crickets, did not stimulate the birds' song activity. However, song activity increased to intermediate levels when live crickets were shown under a clear plastic wrap, i.e., when birds could see but not eat crickets. We hypothesize that the opportunity to see and handle live insects stimulates song and reproductive activity in these birds. Our data indicate for the first time that a tropical rainforest bird can use food cues to evaluate the suitability of local environmental conditions for breeding. (C) 2000 Wiley-Liss, Inc. C1 Univ Illinois, Dept Ecol Ethol & Evolut, Urbana, IL 61801 USA. Univ Washington, Dept Zool, Seattle, WA 98195 USA. Smithsonian Trop Res Inst, Balboa, Ancon, Panama. RP Hau, M (reprint author), Univ Illinois, Dept Ecol Ethol & Evolut, 515 Morrill Hall,505 S Goodwin Ave, Urbana, IL 61801 USA. NR 83 TC 60 Z9 62 U1 1 U2 22 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0022-104X J9 J EXP ZOOL JI J. Exp. Zool. PD APR 1 PY 2000 VL 286 IS 5 BP 494 EP 504 DI 10.1002/(SICI)1097-010X(20000401)286:5<494::AID-JEZ7>3.0.CO;2-3 PG 11 WC Zoology SC Zoology GA 290CC UT WOS:000085657900007 PM 10684573 ER PT J AU Li, X Habbal, SR AF Li, X Habbal, SR TI Proton/alpha magnetosonic instability in the fast solar wind SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ION-BEAM INSTABILITIES; HEAVY-IONS; RESONANT ACCELERATION; ALFVEN WAVES; ULYSSES; PLASMA; PROTONS; 0.3-AU; 1-AU AB A proton/alpha magnetosonic instability is investigated in the framework of the linear theory of plasma waves for conditions typical of the fast solar wind. Warm streaming alpha particles with a differential speed, the speed relative to the major ions/protons, v(alpha), close to the Alfven speed, are found to significantly enhance a magnetosonic instability when their temperature anisotropy Gamma(i) = Ti-perpendicular to/Ti-parallel to is less than 1. Here T-i parallel to and T-i perpendicular to denote the velocity distribution parallel and perpendicular to the magnetic field. The possible role of the instability in limiting the relative speed between alpha particles and protons in the fast solar wind is discussed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Li, X (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 45 TC 27 Z9 27 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 1 PY 2000 VL 105 IS A4 BP 7483 EP 7489 DI 10.1029/1999JA000259 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 300FZ UT WOS:000086222800008 ER PT J AU Chung, HK Cohen, DH MacFarlane, JJ Bailey, JE Wang, P Moses, GA AF Chung, HK Cohen, DH MacFarlane, JJ Bailey, JE Wang, P Moses, GA TI Statistical fitting analysis of Stark-broadened optically thick ArII spectra measured in ion beam transport experiments SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID IONIZED ARGON LINES; ATOMIC PARAMETERS; PROBABILITIES AB We present a method for fitting a multi-line spectrum with an emission model that accounts for multiple line-broadening mechanisms and the effects of finite optical depth. This technique includes an analysis of the joint-probability distribution of the model parameters that allows one to determine statistically valid confidence limits on the fitted parameters. We apply this method to a time series of optical Ar II spectra produced when an intense lithium beam (kinetic energy of 9 MeV and current density of 22 kA cm(-2)) was injected into an argon gas cell. We show that line optical depth effects are important in these data, and by including finite optical depth as well as Stark and Doppler broadening in the model-fitting procedure, we are able to place meaningful constraints on the time-dependent Ar II level populations and the electron density in the gas cell. The values we derive for these quantities are in reasonably good agreement with detailed collisional-radiative models that include the effects of non-thermal electrons and beam ions. Understanding the time-dependent conditions in the gas cell is critical for efficient beam transport. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Prism Computat Sci, Madison, WI 53703 USA. Univ Delaware, Bartol Res Inst, Newark, DE 19711 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Wisconsin, Fus Technol Inst, Madison, WI 53706 USA. RP Chung, HK (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS-14, Cambridge, MA 02138 USA. NR 11 TC 0 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD APR-MAY PY 2000 VL 65 IS 1-3 BP 135 EP 149 DI 10.1016/S0022-4073(99)00062-X PG 15 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 275TR UT WOS:000084836700014 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI The painted panorama. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Libs, Washington, DC USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Libs, Washington, DC USA. NR 1 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 1 PY 2000 VL 125 IS 6 BP 94 EP + PG 2 WC Information Science & Library Science SC Information Science & Library Science GA 297KB UT WOS:000086080800053 ER PT J AU Yan, M Dalgarno, A Klemperer, W Miller, AES AF Yan, M Dalgarno, A Klemperer, W Miller, AES TI The CO Cameron band emission in the Red Rectangle SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE molecular processes; ISM : individual : Red Rectangle; ultraviolet : ISM ID ELECTRON-IMPACT EXCITATION; ULTRAVIOLET-SPECTRUM; RECOMBINATION; PRODUCTS; HD-44179; STATES AB The origin of the strong CO Cameron band emission in the Red Rectangle is investigated. From a comparison of laboratory spectroscopic data and astronomical observations in combination with chemical modelling, it is concluded that the Cameron band emission of CO originates from the dissociative recombination of HCO+, and its intensity provides a measure of the product of the density of HCO+ ions and the electron density, integrated along the line of sight. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Dept Chem, Cambridge, MA 02138 USA. RP Yan, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 15 TC 10 Z9 10 U1 0 U2 2 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 1 PY 2000 VL 313 IS 2 BP L17 EP L18 DI 10.1046/j.1365-8711.2000.03421.x PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 301NX UT WOS:000086317200001 ER PT J AU Bahrim, B Kurpick, P Thumm, U Wille, U AF Bahrim, B Kurpick, P Thumm, U Wille, U TI Electron dynamics and level broadening in slow atomic interactions with metal surfaces and thin metallic films SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 18th International Conference on Atomic Collisions in Solids (ICACS-18) CY AUG 03-08, 1999 CL ODENSE, DENMARK ID HIGHLY-CHARGED IONS; RYDBERG ATOMS; FIRST-ORDER; ADIABATIC EVOLUTION; GRAZING-INCIDENCE; HYDROGENIC LEVELS; ALUMINUM SURFACE; MATRIX-ELEMENTS; BARRIER MODEL; ENERGY SHIFTS AB Theoretical results on the electron dynamics and on resonant level broadening in slow atomic interactions with metal surfaces and thin metallic films are presented. Within the time-dependent close-coupling method, a wave-packet approach is introduced in which nondiagonal couplings in the subspace of metal states are taken into account. This approach is applied in a study of the time evolution of the occupation of hydrogen states in front of a semi-infinite metal. First-order level widths are calculated for hydrogenic atoms interacting with thin metallic Alms. They are found to exhibit pronounced size-quantization effects arising from the confinement of the electronic motion in the growth direction of the film. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Hahn Meitner Inst Berlin GmbH, Bereich Theoret Phys, D-14109 Berlin, Germany. Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Wille, U (reprint author), Hahn Meitner Inst Berlin GmbH, Bereich Theoret Phys, Glienicker Str, D-14109 Berlin, Germany. EM wille@hmi.de OI Thumm, Uwe/0000-0001-9378-6601 NR 53 TC 12 Z9 12 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD APR PY 2000 VL 164 BP 614 EP 625 DI 10.1016/S0168-583X(99)01158-1 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 313WK UT WOS:000087022500078 ER PT J AU Jankowski, JJ Kieber, DJ Mopper, K Neale, PJ AF Jankowski, JJ Kieber, DJ Mopper, K Neale, PJ TI Development and intercalibration of ultraviolet solar actinometers SO PHOTOCHEMISTRY AND PHOTOBIOLOGY LA English DT Article ID AQUEOUS-SOLUTION; UV-B; ABSORPTION CONSTANTS; QUANTUM YIELDS; FRESH-WATER; NITRITE ION; RADIATION; NITRATE; PHOTOLYSIS; METER AB Ultraviolet (UV) sunlight actinometers were developed based on the photolysis of nitrate and nitrite. Photon exposures (i.e, time-integrated irradiances) were quantified from the photochemical production of salicylic acid (SA) or p-hydroxybenzoic acid (pHBA) formed by the reaction of the hydroxyl radical with benzoic acid. The solar response bandwidth for the nitrate actinometer in quartz tubing was 322 +/- 11 mn during the Spring of 1999, while the response bandwidth of the Mylar D-filtered nitrite actinometer was 355 +/- 25 nm. Intercomparisons of the nitrate and nitrite actinometers with a Smithsonian Environmental Research Center SR-18 scanning UV-B radiometer (SERC SR-18) and an Optronics OL-754 spectroradiometer (OL-754) were performed during the summer of 1998, and the winter and spring of 1999, Photon exposures determined by the nitrate actinometer were in excellent agreement with the SERC SR-18, with a slope (95% confidence interval [CI]) of 0.98 +/- 0.01 based on SA production and 0.94 +/- 0.02 based on pHBA production, Excellent agreement was also found between the nitrite actinometer and the OL-754, with a slope (95% CI) of 1.00 +/- 0.01 using SA production and 1.00 +/- 0.02 using pHBA production. These actinometers are well suited for use in the water column and are sufficiently sensitive to determine photon exposures below the 0.1% UV light-level. C1 SUNY Coll Environm Sci & Forestry, Dept Chem, Syracuse, NY 13210 USA. Washington State Univ, Dept Chem, Pullman, WA 99164 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Kieber, DJ (reprint author), SUNY Coll Environm Sci & Forestry, Dept Chem, 1 Forestry Dr, Syracuse, NY 13210 USA. RI Neale, Patrick/A-3683-2012 NR 47 TC 29 Z9 29 U1 4 U2 17 PU AMER SOC PHOTOBIOLOGY PI AUGUSTA PA BIOTECH PARK, 1021 15TH ST, SUITE 9, AUGUSTA, GA 30901-3158 USA SN 0031-8655 J9 PHOTOCHEM PHOTOBIOL JI Photochem. Photobiol. PD APR PY 2000 VL 71 IS 4 BP 431 EP 440 DI 10.1562/0031-8655(2000)071<0431:DAIOUS>2.0.CO;2 PG 10 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 305LA UT WOS:000086540500011 ER PT J AU Jamieson, MJ Dalgarno, A Wolniewicz, L AF Jamieson, MJ Dalgarno, A Wolniewicz, L TI Calculation of properties of two-center systems SO PHYSICAL REVIEW A LA English DT Article ID ALKALI-METAL DIMERS; STATE AB A procedure is described by which the response of a two-center system to a perturbation can be expressed in terms of single-center wave functions. We use the formulation to evaluate the asymptotic long-range part of the Pauli-Dirac relativistic interaction between two ground-state hydrogen atoms and compare with the results of ab initio calculations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Nicholas Copernicus Univ, Inst Phys, PL-87100 Torun, Poland. Univ Glasgow, Dept Comp Sci, Glasgow G12 8QQ, Lanark, Scotland. RP Jamieson, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Wolniewicz, Lutoslaw/R-1808-2016 NR 16 TC 29 Z9 29 U1 0 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 2000 VL 61 IS 4 AR 042705 DI 10.1103/PhysRevA.61.042705 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 301ME UT WOS:000086313300046 ER PT J AU Maitra, NT Heller, EJ AF Maitra, NT Heller, EJ TI Quantum transport through cantori SO PHYSICAL REVIEW E LA English DT Article ID HAMILTONIAN-SYSTEMS; PERIODIC-ORBITS; DYNAMICS; BEHAVIOR AB We study the effect of classical cantori in quantum mechanics, extending previous results by several groups. We find that cantori form exponential barriers to quantum transport not only when Planck's constant exceeds the flux through the cantorus but also when it is smaller than the flux. The mechanism of localization in the two cases is different, and we describe the switch from dynamical localization to a mechanism we call "retunneling'' as Planck's constant increases. We investigate the h dependence of the exponential decay for retunneling and find that the (h) over bar(-0.66) coefficient found previously at criticality appears to hold also away from criticality provided pi (h) over bar is large enough compared to the flux. Numerical evidence as well as an analytic argument are given. Our final contribution to this subject is a phase space view of cantori in quantum mechanics. We illustrate our results using the whisker map. C1 Harvard Univ, Dept Phys, Cambridge, MA 02138 USA. Harvard Univ, Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Dept Chem, Cambridge, MA 02138 USA. RP Maitra, NT (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 40 TC 19 Z9 20 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD APR PY 2000 VL 61 IS 4 BP 3620 EP 3631 DI 10.1103/PhysRevE.61.3620 PN A PG 12 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 306LA UT WOS:000086597100046 ER PT J AU Saluke, SV Pogue, MG AF Saluke, SV Pogue, MG TI Resolution of the Elaphria festivoides (Guenee) species complex (Lepidoptera : Noctuidae) SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Elaphria cornutinis; Elaphria festivoides taxonomy; distribution AB A new species, Elaphria cornutinis, of the Elaphria festivoides Guenee species complex is described and illustrated. E. festivoides is redescribed and variation within the species discussed. Elaphria cornutinis can be distinguished from E. festivoides by the darker ground color of the forewing and more distinct orbicular and claviform spots. The male has an abdominal hair pencil, a gradually narrowing valve, and a narrower uncus than in that of E. festivoides. Elaphria festivoides is widely distributed from southern Canada to southern Texas and Florida, west to eastern British Columbia, Colorado, and New Mexico. Elaphria cornutinis overlaps the distribution of E. festivoides from Maryland south to Alabama and west to Oklahoma and Missouri. A total of 796 specimens were studied, with 41 specimens of E. festivoides and 15 specimens of E. cornutinis dissected for genitalic examination. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Entomol, Washington, DC 20560 USA. Smithsonian Inst, Natl Museum Nat Hist, Systemat Entomol Lab, PSI,Agr Res Serv,US Dept Agr, Washington, DC 20560 USA. RP Saluke, SV (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Entomol, Washington, DC 20560 USA. NR 19 TC 3 Z9 3 U1 1 U2 1 PU ENTOMOL SOC WASHINGTON PI WASHINGTON PA SMITHSONIAN INSTITUTION DEPT ENTOMOLOGY, WASHINGTON, DC 20560 USA SN 0013-8797 J9 P ENTOMOL SOC WASH JI Proc. Entomol. Soc. Wash. PD APR PY 2000 VL 102 IS 2 BP 233 EP 270 PG 38 WC Entomology SC Entomology GA 305KQ UT WOS:000086539300001 ER PT J AU Wahis, R Krombein, KV AF Wahis, R Krombein, KV TI A new Machaerothrix Haupt from Sri Lanka with notes on the genus (Hymenoptera : Pompilidae : Pepsinae : Ageniellini) SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Hymenoptera; Pompilidae (Ageniellini); Machaerothrix; Sri Lanka; new taxon AB A new taxon of Machaerothrix Haupt, M. johni Wahis, is described and illustrated from both sexes; descriptive notes are included for a melanistic form of M. johni restricted to the Sinharaja Rain Forest. A provisional key to the known species is provided. An English translation of the description of M. ussuriensis Lelej is given. C1 Fac Univ Sci Agron Zool Gen & Appl, B-5030 Gembloux, Belgium. Smithsonian Inst, Natl Museum Nat Hist, Dept Entomol, Washington, DC 20560 USA. RP Wahis, R (reprint author), Fac Univ Sci Agron Zool Gen & Appl, B-5030 Gembloux, Belgium. NR 8 TC 3 Z9 3 U1 1 U2 2 PU ENTOMOL SOC WASHINGTON PI WASHINGTON PA SMITHSONIAN INSTITUTION DEPT ENTOMOLOGY, WASHINGTON, DC 20560 USA SN 0013-8797 J9 P ENTOMOL SOC WASH JI Proc. Entomol. Soc. Wash. PD APR PY 2000 VL 102 IS 2 BP 271 EP 279 PG 9 WC Entomology SC Entomology GA 305KQ UT WOS:000086539300002 ER PT J AU Adamski, D Metzler, EH AF Adamski, D Metzler, EH TI A new species of Glyphidocera Walsingham from southwestern Ohio (Lepidoptera : Gelechioidea : Glyphidoceridae) SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Glyphidoceridae; natural resources; national historic site ID GREENE COUNTY AB Glyphidocera wrightorum, new species, is described and illustrated from Huffman Prairie in Southwestern Ohio, USA. Huffman Prairie is a 109-acre prairie on Wright-Patterson Air Force Base. C1 Smithsonian Inst, Natl Museum Nat Hist, MRC 127, Dept Entomol, Washington, DC 20560 USA. Ohio Lepidopterists, Columbus, OH 43229 USA. RP Adamski, D (reprint author), Smithsonian Inst, Natl Museum Nat Hist, MRC 127, Dept Entomol, Washington, DC 20560 USA. NR 11 TC 2 Z9 2 U1 0 U2 0 PU ENTOMOL SOC WASHINGTON PI WASHINGTON PA SMITHSONIAN INSTITUTION DEPT ENTOMOLOGY, WASHINGTON, DC 20560 USA SN 0013-8797 J9 P ENTOMOL SOC WASH JI Proc. Entomol. Soc. Wash. PD APR PY 2000 VL 102 IS 2 BP 301 EP 307 PG 7 WC Entomology SC Entomology GA 305KQ UT WOS:000086539300005 ER PT J AU Li, CS Hueber, FM AF Li, CS Hueber, FM TI Cervicornus wenshanensis, gen. et sp nov, a Pragian (Early Devonian) plant with forked leaves from Yunnan, China SO REVIEW OF PALAEOBOTANY AND PALYNOLOGY LA English DT Article DE Cervicornus; China; Early Devonian; Plantae; Pragian ID EARLY LAND PLANTS; AGLAOPHYTON-MAJOR; RHYNIE CHERT; LECLERCQIA; PROVINCE; ZOSTEROPHYLL; LYCOPOD AB Cervicornus wenshanensis gen. et sp. nov. is described from compressions of leaf-bearing, vegetative stems of Pragian age (Early Devonian). Stelar anatomy is not preserved. The plant is described as herbaceous with leaves arranged in openly spaced helices. The distal portion of each of the leaves is divided three times, resulting in eight segments resembling the antler of a deer. The arrangement and morphology of the leaves suggest a possible relationship with the lycopsid family Protolepidodendraceae in which, among the genera, the leaves are helically arranged and variously divided. Additionally, the members of the family are united on the basis of stelar anatomy and the presence of sporangia. Neither of the latter characteristics, which are essential to the unequivocal assignment to the family, are preserved in Cervicornus. The genus is a noteworthy morphological variant among Devonian plants, but the arrangement of the leaves and their morphology cannot be used alone to infer an affinity with a taxon of higher rank. As with many other fragmentary paleobotanical entities, lacking sufficient definitive characteristics and awaiting discovery and description of additional specimens, we have proposed a classification of this new genus and species as incertae sedis. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Smithsonian Inst, Dept Paleobiol, Washington, DC 20560 USA. Chinese Acad Sci, Inst Bot, Beijing 100093, Peoples R China. RP Hueber, FM (reprint author), Smithsonian Inst, Dept Paleobiol, Washington, DC 20560 USA. NR 49 TC 8 Z9 10 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0034-6667 J9 REV PALAEOBOT PALYNO JI Rev. Palaeobot. Palynology PD APR PY 2000 VL 109 IS 2 BP 113 EP 119 DI 10.1016/S0034-6667(99)00046-9 PG 7 WC Plant Sciences; Paleontology SC Plant Sciences; Paleontology GA 320NT UT WOS:000087407800002 ER PT J AU Bromage, BJJ Alexander, D Breen, A Clegg, JR Del Zanna, G DeForest, C Dobrzycka, D Gopalswamy, N Thompson, B Browning, PK AF Bromage, BJJ Alexander, D Breen, A Clegg, JR Del Zanna, G DeForest, C Dobrzycka, D Gopalswamy, N Thompson, B Browning, PK TI Structure of a large low-latitude coronal hole SO SOLAR PHYSICS LA English DT Article ID WHOLE SUN MONTH; SOLAR-WIND; INTERPLANETARY SCINTILLATION; ELEPHANTS TRUNK; SOHO MISSION; SPECTROMETER; TELESCOPE; BOUNDARY; FIELD AB Coronal holes on the Sun are the source of high-speed solar wind streams that produce magnetic disturbances at the Earth. A series of multi-wavelength, multi-instrument observations obtained during the 1996 'Whole Sun Month' campaign examined a large coronal hole in greater detail than ever before. It appeared on the Sun in August, and extended from the north pole to a large active region in the southern hemisphere. Its physical and magnetic structure and subsequent evolution are described. C1 Univ Cent Lancashire, Ctr Astrophys, Preston PR1 2HE, Lancs, England. Lockheed Martin Solar & Astrophys Lab, Palo Alto, CA USA. Max Planck Inst Aeron, Katlenburg Lindau, Germany. NASA, Goddard Space Flight Ctr, SOHO SOI MDI, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Catholic Univ Amer, NASA, GSFC, Greenbelt, MD USA. NASA, Goddard Space Flight Ctr, Space Applicat Corp, Greenbelt, MD 20771 USA. Univ Manchester, Inst Sci & Technol, Manchester M60 1QD, Lancs, England. RP Bromage, BJJ (reprint author), Univ Cent Lancashire, Ctr Astrophys, Preston PR1 2HE, Lancs, England. RI Gopalswamy, Nat/D-3659-2012; Thompson, Barbara/C-9429-2012 NR 29 TC 26 Z9 26 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 APR PY 2000 VL 193 IS 1-2 BP 181 EP 193 DI 10.1023/A:1005209725885 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 354XV UT WOS:000089357300012 ER PT J AU Eff-Darwich, A Korzennik, SG AF Eff-Darwich, A Korzennik, SG TI Response of the radial stratification at the base of the convection zone to the activity cycle SO SOLAR PHYSICS LA English DT Article ID P-MODES; SOLAR AB We have analyzed the differences in the oscillation eigenfrequencies measured over more than two years of GONG observations (December 1995-April 1998) and SOI/MDI observations (May 1996-July 1998). We have inverted these data to look for signatures of the solar activity cycle on the stratification. A one-dimensional (radial) structure inversion code was used to study temporal variations of the sound speed distribution at the boundary between the radiative and convective zones. Such variations could be an indication of the presence of a toroidal magnetic field anchored in this region. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 20 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 EI 1573-093X J9 SOL PHYS JI Sol. Phys. PD APR PY 2000 VL 193 IS 1-2 BP 365 EP 371 DI 10.1023/A:1005201131631 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 354XV UT WOS:000089357300024 ER PT J AU Laurance, WF AF Laurance, WF TI Do edge effects occur over large spatial scales? SO TRENDS IN ECOLOGY & EVOLUTION LA English DT Editorial Material ID FOREST FRAGMENTS; AMAZON C1 Natl Inst Amazonian Res INPA, Biol Dynam Forest Fragments Project, BR-69011970 Manaus, Amazonas, Brazil. Natl Museum Nat Hist, Smithsonian Inst, Washington, DC 20560 USA. RP Laurance, WF (reprint author), Natl Inst Amazonian Res INPA, Biol Dynam Forest Fragments Project, CP 478, BR-69011970 Manaus, Amazonas, Brazil. RI Laurance, William/B-2709-2012 NR 18 TC 168 Z9 186 U1 3 U2 40 PU ELSEVIER SCIENCE LONDON PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0169-5347 J9 TRENDS ECOL EVOL JI Trends Ecol. Evol. PD APR PY 2000 VL 15 IS 4 BP 134 EP 135 DI 10.1016/S0169-5347(00)01838-3 PG 2 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 298NN UT WOS:000086146200005 ER PT J AU Leigh, EG AF Leigh, EG TI Cognitive ecology: field or label? Reply SO TRENDS IN ECOLOGY & EVOLUTION LA English DT Letter C1 Smithsonian Inst, Smithsonian Trop Res Inst, Washington, DC 20560 USA. RP Leigh, EG (reprint author), Smithsonian Inst, Smithsonian Trop Res Inst, Washington, DC 20560 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE LONDON PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0169-5347 J9 TRENDS ECOL EVOL JI Trends Ecol. Evol. PD APR PY 2000 VL 15 IS 4 BP 162 EP 162 PG 1 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 298NN UT WOS:000086146200014 ER PT J AU Harms, KE Wright, SJ Calderon, O Hernandez, A Herre, EA AF Harms, KE Wright, SJ Calderon, O Hernandez, A Herre, EA TI Pervasive density-dependent recruitment enhances seedling diversity in a tropical forest SO NATURE LA English DT Article ID JANZEN-CONNELL MODEL; NEOTROPICAL FOREST; TREE; SPECIFICITY; HERBIVORY; SURVIVAL; DISTANCE AB Negative density-dependent recruitment of seedlings, that is, seeds of a given species are less likely to become established seedlings if the density of that species is high, has been proposed to be an important mechanism contributing to the extraordinary diversity of tropical tree communities(1-3) because it can potentially prevent any particular species from usurping all available space, either in close proximity to seed sources or at relatively larger spatial scales(1-18). However, density-dependent recruitment does not necessarily enhance community diversity(14). Furthermore, although density-dependent effects have been found at some life stages in some species(3-13), no study has shown that density-dependent recruitment affects community diversity(14,15). Here we report the results of observations in a lowland, moist forest in the Republic of Panama in which the species identities of 386,027 seeds that arrived at 200 seed traps were compared with the species identities of 13,068 seedlings that recruited into adjacent plots over a 4-year period. Across the 200 sites, recruit seedling diversity was significantly higher than seed diversity. Part of this difference was explained by interspecies differences in average recruitment success. Even after accounting for these differences, however, negative density-dependent recruitment contributes significantly to the increase in diversity from Seeds to seedling recruits. C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Wright, SJ (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. RI Wright, Stuart/M-3311-2013 OI Wright, Stuart/0000-0003-4260-5676 NR 27 TC 523 Z9 599 U1 20 U2 153 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAR 30 PY 2000 VL 404 IS 6777 BP 493 EP 495 DI 10.1038/35006630 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 300MX UT WOS:000086257700047 PM 10761916 ER PT J AU Cote, R Jamieson, MJ Yan, ZC Geum, N Jeung, GH Dalgarno, A AF Cote, R Jamieson, MJ Yan, ZC Geum, N Jeung, GH Dalgarno, A TI Enhanced cooling of hydrogen atoms by lithium atoms SO PHYSICAL REVIEW LETTERS LA English DT Article ID BOSE-EINSTEIN CONDENSATION; LONG-RANGE INTERACTIONS; SCATTERING LENGTHS; COLLISIONS; STATE; GAS AB We present calculated scattering lengths, for collisions between various isotopic forms of lithium and hydrogen atoms interacting via singlet and triplet molecular states of LiH. We demonstrate that one bound triplet level is supported for each isotopomer (LiH)-Li-7, (LiH)-Li-6, 7LiD, and (LiD)-Li-6. We obtain large calculated triplet scattering lengths that are stable against uncertainties in the potential. We present elastic and momentum transfer cross sections, and the corresponding rate coefficients, for hydrogen atoms colliding with Li-7 atoms. We suggest that enhanced cooling of trapped atomic hydrogen by Li-7 atoms is feasible. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. Univ Glasgow, Dept Comp Sci, Glasgow G12 8QQ, Lanark, Scotland. Univ New Brunswick, Dept Phys, Fredericton, NB E3B 5A3, Canada. Dankook Univ, Dept Chem, Cheonan 330714, South Korea. Univ Paris Sud, CNRS UPR 3321, Aime Cotton Lab, F-91405 Orsay, France. RP Cote, R (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Yan, Zong-Chao/F-6668-2014 NR 30 TC 43 Z9 46 U1 2 U2 7 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 27 PY 2000 VL 84 IS 13 BP 2806 EP 2809 DI 10.1103/PhysRevLett.84.2806 PG 4 WC Physics, Multidisciplinary SC Physics GA 297BQ UT WOS:000086062000010 ER PT J AU Lukin, MD Hemmer, PR AF Lukin, MD Hemmer, PR TI Quantum entanglement via optical control of atom-atom interactions SO PHYSICAL REVIEW LETTERS LA English DT Article ID RESONANCE; DIAMOND AB Two-photon optical transitions combined with long-range dipole-dipole interactions can be used for the coherent manipulation of multiatom collective states. We show that it is possible to induce optical resonances accompanied by the generation of entangled superpositions of such atomic states. Resonances of this kind can be used to implement quantum logic gates using optically excited single atoms (impurities) in the condensed phase. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. USAF, Res Lab, Sensors Directorate, Bedford, MA 01731 USA. RP Lukin, MD (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. NR 18 TC 100 Z9 102 U1 0 U2 7 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 27 PY 2000 VL 84 IS 13 BP 2818 EP 2821 DI 10.1103/PhysRevLett.84.2818 PG 4 WC Physics, Multidisciplinary SC Physics GA 297BQ UT WOS:000086062000013 ER PT J AU Pierpaoli, E Scott, D White, M AF Pierpaoli, E Scott, D White, M TI Astronomy - How flat is the universe? SO SCIENCE LA English DT Editorial Material ID MICROWAVE C1 Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Pierpaoli, E (reprint author), Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. EM elena@astro.ubc.ca; dscott@astro.ubc.ca; mwhite@cfa.harvard.edu RI White, Martin/I-3880-2015; OI White, Martin/0000-0001-9912-5070; Pierpaoli, Elena/0000-0002-7957-8993 NR 18 TC 9 Z9 9 U1 0 U2 0 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 MAR 24 PY 2000 VL 287 IS 5461 BP 2171 EP 2172 DI 10.1126/science.287.5461.2171 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 296WE UT WOS:000086049100026 ER PT J AU Zeder, MA Hesse, B AF Zeder, MA Hesse, B TI The initial domestication of goats (Capra hircus) in the Zagros mountains 10,000 years ago SO SCIENCE LA English DT Article AB Initial goat domestication is documented in the highlands of western Iran at 10,000 calibrated calendar years ago. Metrical analyses of patterns of sexual dimorphism in modern wild goat skeletons (Capra hircus aegagrus) allow sex-specific age curves to be computed for archaeofaunal assemblages, A distinct shift to selective harvesting of subadult males marks initial human management and the transition from hunting to herding of the species. Direct accelerator mass spectrometry radiocarbon dates on skeletal elements provide a tight temporal context for the transition. C1 Natl Museum Nat Hist, Dept Anthropol, Archaeobiol Program, Smithsonian Inst, Washington, DC 20560 USA. Univ Alabama, Dept Anthropol, Birmingham, AL 35294 USA. RP Zeder, MA (reprint author), Natl Museum Nat Hist, Dept Anthropol, Archaeobiol Program, Smithsonian Inst, Washington, DC 20560 USA. EM zeder.melinda@nmnh.si.edu NR 18 TC 204 Z9 221 U1 7 U2 40 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 MAR 24 PY 2000 VL 287 IS 5461 BP 2254 EP 2257 DI 10.1126/science.287.5461.2254 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 296WE UT WOS:000086049100048 PM 10731145 ER PT J AU Cecchi-Pestellini, C Dalgarno, A AF Cecchi-Pestellini, C Dalgarno, A TI H-3(+) in diffuse interstellar gas SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE molecular processes; ISM : clouds; ISM : molecules AB A model is constructed of the material in front of the star Cygnus OB2 no. 12 in which dense cores are embedded in diffuse clumps of gas. The model reproduces the measured abundances of H-3(+), C-2 and CO, and predicts a column density of 9 x 10(10) cm(-2) HCO+. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. RP Cecchi-Pestellini, C (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 17 TC 28 Z9 28 U1 0 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAR 21 PY 2000 VL 313 IS 1 BP L6 EP L8 DI 10.1046/j.1365-8711.2000.03320.x PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 300UV UT WOS:000086272200002 ER PT J AU Esser, R Edgar, RJ AF Esser, R Edgar, RJ TI Reconciling spectroscopic electron temperature measurements in the solar corona with in situ charge state observations SO ASTROPHYSICAL JOURNAL LA English DT Article DE solar wind; sun : atmosphere; sun : corona ID HOLES; IONS AB It has been a puzzle for quite some time that spectroscopic measurements in the inner corona indicate electron temperatures far too low to produce the ion fractions observed in situ in the solar wind. In the present Letter, we show that in order to reconcile the two sets of measurements, a number of conditions have to exist in the inner corona: (1) The electron distribution function has to be Maxwellian or dose to Maxwellian at the coronal base, (2) the non-Maxwellian character of the distribution has to develop rapidly as a function of height and has to reach close to interplanetary properties inside of a few solar radii, and (3) ions of different elements have to flow with significantly different speeds to separate their "freezing-in" distances sufficiently so that they can encounter different distribution functions. We choose two examples to demonstrate that these conditions are general requirements if both coronal electron temperatures and in situ ion fractions are correct. However, these two examples also show that the details of the required distribution functions are very sensitive to the exact electron temperature, density, and ion flow speed profiles in the region of the corona where the ions predominantly form. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Esser, R (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 23 TC 62 Z9 62 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2000 VL 532 IS 1 BP L71 EP L74 DI 10.1086/312548 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 301VH UT WOS:000086330600018 ER PT J AU Mazeh, T Naef, D Torres, G Latham, DW Mayor, M Beuzit, JL Brown, TM Buchhave, L Burnet, M Carney, BW Charbonneau, D Drukier, GA Larid, JB Pepe, F Perrier, C Queloz, D Santos, NC Sivan, JP Udry, S Zucker, S AF Mazeh, T Naef, D Torres, G Latham, DW Mayor, M Beuzit, JL Brown, TM Buchhave, L Burnet, M Carney, BW Charbonneau, D Drukier, GA Larid, JB Pepe, F Perrier, C Queloz, D Santos, NC Sivan, JP Udry, S Zucker, S TI The spectroscopic orbit of the planetary companion transiting HD 209458 SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : eclipsing; planetary systems; stars : individual (HD 209458); techniques : radial velocities ID RADIAL-VELOCITIES; HIGH-RESOLUTION; STELLAR MODELS; STARS; DWARFS AB We report a spectroscopic orbit with period P = 3.52433 +/- 0.00027 days for the planetary companion that transits the solar-type star HD 209458. For the metallicity, mass, and radius of the star, we derive [Fe/H] = 0.00 +/- 0.02, M* = 1.1 +/- 0.1 M-circle dot, and R* = 1.2 +/- 0.1 R-circle dot. This is based on a new analysis of the iron lines in our HIRES template spectrum and also on the absolute magnitude, effective temperature, and color of the star, and it uses isochrones from four different sets of stellar evolution models. Using these values for the stellar parameters, we reanalyze the transit data and derive an orbital inclination of i = 86 degrees.1 +/- 1 degrees.6. For the planet, we derive a mass of M-p = 0.69 +/- 0.05 M-Jup, a radius of R-p = 1.40 +/- 0.17 R-Jup, and a density of rho = 0.31 +/- 0.07 g cm(-3). C1 Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Observ Geneva, CH-1290 Sauverny, Switzerland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Observ Grenoble, Astrophys Lab, F-38041 Grenoble, France. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. Univ Copenhagen, Astron Observ, Niels Bohr Inst Astron Phys & Geophys, DK-1168 Copenhagen, Denmark. Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Bowling Green State Univ, Dept Phys & Astron, Bowling Green, OH 43403 USA. Observ Haute Provence, St Michel Observ, St Michel, France. RP Mazeh, T (reprint author), Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. RI Santos, Nuno/E-9957-2011 OI Santos, Nuno/0000-0003-4422-2919 NR 35 TC 112 Z9 114 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2000 VL 532 IS 1 BP L55 EP L58 DI 10.1086/312558 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 301VH UT WOS:000086330600014 ER PT J AU Medvedev, MV AF Medvedev, MV TI Interstellar scintillations of polarization of compact sources SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : general; scattering; techniques : interferometric; techniques : polarimetric ID GAMMA-RAY-BURST; PULSAR SCINTILLATION; SPECTRUM AB We demonstrate that the measurement of fluctuations of polarization due to the Galactic interstellar scintillations may be used to study the structure of the radiation field at compact radio sources. We develop a mathematical formalism and demonstrate it on a simple analytical model in which the scale of the polarization variation through the source is comparable to the source size. The predicted amplitude of modulation of the polarized radiation flux is similar to(20%) pi(s)m(sc), where pi(s) is the characteristic degree of polarization of radiation at the source and m(sc) is the typical modulation index due to scattering, i.e., m(sc) similar or equal to 1 for diffractive scintillations and m(sc) < 1 for refractive scintillations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RRC Kurchatov Inst, Inst Nucl Fus, Moscow, Russia. RP Medvedev, MV (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 14 TC 2 Z9 2 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 2000 VL 532 IS 1 BP L63 EP L66 DI 10.1086/312554 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 301VH UT WOS:000086330600016 ER PT J AU Koike, M Kondo, Y Irie, H Murcray, FJ Williams, J Fogal, P Blatherwick, R Camy-Peyret, C Payan, S Oelhaf, H Wetzel, G Traub, W Johnson, D Jucks, K Toon, GC Sen, B Blavier, JF Schlager, H Ziereis, H Toriyama, N Danilin, MY Rodriguez, JM Kanzawa, H Sasano, Y AF Koike, M Kondo, Y Irie, H Murcray, FJ Williams, J Fogal, P Blatherwick, R Camy-Peyret, C Payan, S Oelhaf, H Wetzel, G Traub, W Johnson, D Jucks, K Toon, GC Sen, B Blavier, JF Schlager, H Ziereis, H Toriyama, N Danilin, MY Rodriguez, JM Kanzawa, H Sasano, Y TI A comparison of Arctic HNO3 profiles measured by the Improved Limb Atmospheric Spectrometer and balloon-borne sensors SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID FEBRUARY 1995; VORTEX; CAMPAIGN; STRATOSPHERE; SYSTEM AB The Improved Limb Atmospheric Spectrometer (ILAS), a solar occultation infrared satellite sensor, was launched in August 1996. The ILAS validation balloon campaigns were carried out from Kiruna, Sweden (68 degrees N, 21 degrees E), in February and March 1997 and Fairbanks, Alaska (65 degrees N, 148 degrees W), in April and May 1997. During these campaigns, measurements of nitric acid (HNO3) were made using infrared emission spectrometers (Cold Atmospheric Emission Spectral Radiometer, Michelson Interferometer for Passive Atmospheric Sounding-Balloon-Borne version 2, and far-infrared spectrometer) and infrared solar occultation spectrometers (Limb Profile Monitor of the Atmosphere and Mark IV interferometer). An in situ experiment (Chemiluminescence Detector) measured total reactive nitrogen (NOy), from which HNO3 mixing ratios in the lower stratosphere were calculated. In addition, an in situ NO, measurement was also made at 12 km altitude from the Deutsche Luft-und Raumfahrt Falcon aircraft in January 1997. The ILAS version 3.10 HNO3 mixing ratios obtained at the nearest location and averaged ILAS mixing ratios obtained within certain criteria were compared with the balloon data. The precision of the ILAS measurements was estimated from the random differences to be 0.8 parts per billion by volume (ppbv), corresponding to about 35% at 15 km and 10-15% at 20-35 km. While the absolute accuracy estimated from the systematic differences was as good as 0.5 ppbv (5%) at 20 km, the ILAS HNO3 mixing ratios were systematically lower than the balloon values by 1 ppbv (15-20%) at 25-30 km. The error in the altitude registration in the ILAS retrieval algorithm is a possible cause for the negative bias at higher altitudes. C1 Nagoya Univ, Solar Terr Environm Lab, Aichi 4428507, Japan. Univ Denver, Dept Phys, Denver, CO 80210 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. Univ Paris 06, Lab Phys Mol & Applicat, F-75252 Paris 05, France. CNRS, F-75252 Paris 05, France. Atmospher & Environm Res Inc, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Inst Environm Studies, Tsukuba, Ibaraki 305, Japan. Forschungszentrum Karlsruhe, Inst Meteorol & Klimaforsch, D-76021 Karlsruhe, Germany. Deutsch Zentrum Luft & Raumfahrt, Inst Phys Atmosphare, D-82234 Wessling, Germany. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Dept Marine & Atmospher Chem, Coral Gables, FL 33124 USA. RP Koike, M (reprint author), Nagoya Univ, Solar Terr Environm Lab, Aichi 4428507, Japan. EM koike@stelab.nagoya-u.ac.jp RI Sasano, Yasuhiro/C-2927-2009; Koike, Makoto/F-4366-2011; Kondo, Yutaka/D-1459-2012; Wetzel, Gerald/A-7065-2013; Oelhaf, Hermann/A-7895-2013; Rodriguez, Jose/G-3751-2013; Johnson, David/F-2376-2015 OI Sasano, Yasuhiro/0000-0001-7470-5642; Rodriguez, Jose/0000-0002-1902-4649; Johnson, David/0000-0003-4399-5653 NR 25 TC 33 Z9 33 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 16 PY 2000 VL 105 IS D5 BP 6761 EP 6771 DI 10.1029/1999JD901057 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 294KT UT WOS:000085911000012 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI Eyewitness: Reports from an art world in crisis. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Lib, Washington, DC 20560 USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Lib, Washington, DC 20560 USA. NR 1 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 MAR 15 PY 2000 VL 125 IS 5 BP 80 EP 80 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 291XK UT WOS:000085764800042 ER PT J AU Sadeghpour, HR Bohn, JL Cavagnero, MJ Esry, BD Fabrikant, II Macek, JH Rau, ARP AF Sadeghpour, HR Bohn, JL Cavagnero, MJ Esry, BD Fabrikant, II Macek, JH Rau, ARP TI Collisions near threshold in atomic and molecular physics SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Review ID ELECTRON-IMPACT IONIZATION; DIPOLE-SUPPORTED STATES; QUANTUM-DEFECT THEORY; NEAR-THRESHOLD; SCATTERING LENGTHS; MAGNETIC-FIELD; NEGATIVE-IONS; POLAR-MOLECULES; SPIN ASYMMETRY; EFIMOV STATES AB We review topics of current interest in the physics of electronic, atomic and molecular scattering in the vicinity of thresholds. Starting from phase space arguments, we discuss the modifications of the Wigner law that are required to deal with scattering by Coulomb, dipolar and dispersion potentials, as well as aspects of threshold behaviour observed in ultracold atomic collisions. We employ the tools of quantum defect and semiclassical theories to bring out the rich variety of threshold behaviours. The discussion is then turned to recent progress in understanding threshold behaviour of many-body break-ups into both charged and neutral species, including both Wannier double ionization and three-body recombination in ultracold gases. We emphasize the dominant role that hyperspherical coordinate methods have played in understanding these problems. We assess the effects of external fields on scattering, and the corresponding modification of phase space that alters the Wigner law. Threshold laws in low dimensions and examples of their applications to specific collision processes are discussed. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. RP Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. EM hsadeghpour@cfa.harvard.edu RI Esry, Brett/H-7511-2013 OI Esry, Brett/0000-0003-3207-8526 NR 173 TC 135 Z9 136 U1 5 U2 24 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 EI 1361-6455 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD MAR 14 PY 2000 VL 33 IS 5 BP R93 EP R140 DI 10.1088/0953-4075/33/5/201 PG 48 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 299LV UT WOS:000086200800008 ER PT J AU Springel, V AF Springel, V TI Modelling star formation and feedback in simulations of interacting galaxies SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE methods : numerical; galaxies : evolution; galaxies : interactions; galaxies : starburst ID DYNAMICALLY HOT GALAXIES; MERGER REMNANTS; DISK GALAXIES; INTERSTELLAR-MEDIUM; ELLIPTICAL GALAXIES; TRANSFORMATIONS; HYDRODYNAMICS; GASDYNAMICS; PROGENITORS; COLLAPSE AB We discuss a heuristic model to implement star formation and feedback in hydrodynamical simulations of galaxy formation and evolution. In this model, gas is allowed to cool radiatively and to form stars at a rate given by a simple Schmidt-type law. We assume that supernova feedback results in turbulent motions of gas below resolved scales, a process that can pressurize the diffuse gaseous medium effectively, even if it lacks substantial thermal support. Ignoring the complicated detailed physics of the feedback processes, we try to describe their net effect on the interstellar medium with a fiducial second reservoir of internal energy, which accounts for the kinetic energy content of the gas on unresolved scales. Applying the model to three-dimensional, fully self-consistent models of isolated disc galaxies, we show that the resulting feedback loop can be modelled with smoothed particle hydrodynamics such that converged results can be reached with moderate numerical resolution. With an appropriate choice of the free parameters, Kennicutt's phenomenological star formation law can be reproduced over many orders of magnitude in gas surface density. We also apply the model to mergers of equal-mass disc galaxies, typically resulting in strong nuclear starbursts. Confirming previous findings, the presence of a bulge can delay the onset of the starburst from the first encounter of the galaxies until their final coalescence. The final density profiles of the merger remnants are consistent with de Vaucouleurs profiles, except for the innermost region, where the newly created stars give rise to a luminous core with stellar densities that may be in excess of those observed in the cores of most elliptical galaxies. By comparing the isophotal shapes of collisionless and dissipative merger simulations we show that dissipation leads to isophotes that are more discy than those of corresponding collisionless simulations. C1 Max Planck Inst Astrophys, D-85740 Munich, Germany. RP Springel, V (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 65 TC 163 Z9 163 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAR 11 PY 2000 VL 312 IS 4 BP 859 EP 879 DI 10.1046/j.1365-8711.2000.03187.x PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 302WB UT WOS:000086388500023 ER PT J AU Uttley, P MHardy, IM Papadakis, IE Cagnoni, I Fruscione, A AF Uttley, P MHardy, IM Papadakis, IE Cagnoni, I Fruscione, A TI Simultaneous EUV and X-ray variability of NGC 4051 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : active; galaxies : individual : NGC 4051; galaxies : Seyfert; X-rays : galaxies ID SPECTRAL VARIABILITY; GALAXY NGC-4051 AB We present a flux variability study of simultaneous RXTE and EUVE observations of the highly variable Seyfert galaxy NGC 4051. We find a strong correlation between variability in the EUV and medium-energy X-ray bands, indicating that both are sampling the same power-law continuum. The lag between the two bands is less than 20 ks and, depending on model assumptions, may be < 1 ks. We examine the consequences of such a small lag in the context of simple Comptonization models for the production of the power-law continuum. A lag of < 1 ks implies that the size of the Comptonizing region is less than 20 Schwarzschild radii for a black hole of mass > 10(6) M.. C1 Univ Southampton, Dept Phys & Astron, Southampton SO17 1BJ, Hants, England. Univ Crete, Dept Phys, Iraklion 71003, Crete, Greece. SISSA, ISAS, I-34014 Trieste, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Uttley, P (reprint author), Univ Southampton, Dept Phys & Astron, Southampton SO17 1BJ, Hants, England. EM pu@astro.soton.ac.uk RI Papadakis, Iossif/C-3235-2011 NR 32 TC 21 Z9 21 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAR 11 PY 2000 VL 312 IS 4 BP 880 EP 886 DI 10.1046/j.1365-8711.2000.03266.x PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 302WB UT WOS:000086388500024 ER PT J AU McClintock, JE Remillard, RA AF McClintock, JE Remillard, RA TI HST/STIS UV spectroscopy of two quiescent X-ray novae: A0620-00 and Centaurus X-4 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; stars : individual (A0620-00, Centaurus X-4); X-rays : stars ID ADVECTION-DOMINATED ACCRETION; BLACK-HOLE; MODEL; MASS; VARIABILITY; BINARIES; EMISSION; DISKS; STARS AB In 1998 we made UV spectroscopic observations with HST/STIS of A0620-00 and Cen X-4, which are two X-ray novae (also known as soft X-ray transients). These binary systems are similar in all respects except that the former contains a black hole and the latter contains a neutron star. A UV spectrum (1700-3100 ) is presented for the quiescent state of each system in the context of previously published UV/optical and X-ray data. The nonstellar, continuum spectrum of black hole A0620-00 has a prominent UV/optical peak centered at similar to 3500 Angstrom. In contrast the spectrum of neutron star Cen X-4 lacks a peak and rises steadily with frequency over the entire UV/optical band. In the optical, the two systems are comparably luminous. However, black hole A0620-00 is similar to 6 times less luminous at 1700 Angstrom, and similar to 40 times less luminous in the X-ray band. The broadband spectrum of A0620-00 is discussed in terms of the advection-dominated accretion flow model. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. RP McClintock, JE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 40 TC 36 Z9 36 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 2000 VL 531 IS 2 BP 956 EP 962 DI 10.1086/308510 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 299MA UT WOS:000086201300034 ER PT J AU Kenyon, SJ Kolotilov, EA Ibragimov, MA Mattei, JA AF Kenyon, SJ Kolotilov, EA Ibragimov, MA Mattei, JA TI Flickering in FU Orionis SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; stars : formation; stars : individual (FU Orionis); stars : pre-main-sequence ID T-TAURI STARS; SPECTRAL ENERGY-DISTRIBUTIONS; SEQUENCE ACCRETION DISKS; CATACLYSMIC VARIABLES; OBSERVATIONAL CONSTRAINTS; BOUNDARY-LAYER; YOUNG STARS; MODELS; VARIABILITY; EXTINCTION AB We analyze new and published optical photometric data of FU Orionis, an eruptive pre-main-sequence star. The outburst consists of a 5.5 mag rise at B with an e-folding timescale of similar to 50 days. The rates of decline at B and V are identical, 0.015 +/- 0.001 mag yr(-1). Random fluctuations superimposed on this decline have an amplitude of 0.035 +/- 0.005 mag at V and occur on timescales of 1 day or less. Correlations between V and the color indices U-B, B-V, and V-R indicate that the variable source has the optical colors of a GO supergiant. We associate this behavior with small-amplitude flickering of the inner accretion disk. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Uzbek Acad Sci, Ulugh Beg Astron Inst, Tashkent 700052, Uzbekistan. Amer Assoc Variable Star Observers, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM skenyon@cfa.harvard.edu; kolotilov@sai.crimea.ua; mansur@astrin.uzsci.net; jmattei@aavso.org OI Kenyon, Scott/0000-0003-0214-609X NR 58 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 EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 2000 VL 531 IS 2 BP 1028 EP 1036 DI 10.1086/308515 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 299MA UT WOS:000086201300039 ER PT J AU Kling, R Griesmann, U AF Kling, R Griesmann, U TI Accurate f-values for ultraviolet transitions from the 3d(5)(S-6)4p levels in MnII SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic data; methods : laboratory ID HOLLOW-CATHODE AB We have measured branching fractions for ultraviolet electric dipole transitions from upper levels belonging to the 3d(5)(S-6)4p P-7 and 3d(5)(S-6)4p P-5 terms of Mn II. The levels were excited in a hollow cathode lamp and the spectra were observed with a Fourier transform spectrometer. The high signal-to-noise ratio of the Mn II lines in our spectra permitted the measurement of branching fractions even for the weakest transitions in the ultraviolet, which are of particular astrophysical interest. A comparison with previous measurements revealed that many of these measurements, including the most recent, show systematic distortions that may indicate that they are affected by self-absorption. Absolute oscillator strengths, based on the new branching fraction measurements, were determined using existing experimental lifetime data. The uncertainty of the f-values is less than 5% for strong transitions. Oscillator strengths for several very weak intercombination lines with log gf < -2 are reported for the first time. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kling, R (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 24 TC 29 Z9 29 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 2000 VL 531 IS 2 BP 1173 EP 1178 DI 10.1086/308490 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 299MA UT WOS:000086201300053 ER PT J AU Israel, GL Campana, S Covino, S Dal Fiume, D Gaetz, TJ Mereghetti, S Oosterbroek, T Orlandini, M Parmar, AN Ricci, D Stella, L AF Israel, GL Campana, S Covino, S Dal Fiume, D Gaetz, TJ Mereghetti, S Oosterbroek, T Orlandini, M Parmar, AN Ricci, D Stella, L TI BeppoSAX and Chandra observations of SAX J0103.2-7209=2E 0101.5-7225: A new persistent 345 second X-ray pulsar in the small magellanic cloud SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : general; pulsars : individual (SAX J0103.2-7209, 2E 0101.5-7225); stars : emission-line, Be; stars : rotation; X-rays : stars ID ORBITAL PERIOD; DISCOVERY; BINARIES; STARS AB We report the results of a 1998 July BeppoSAX observation of a field in the Small Magellanic Cloud which led to the discovery of similar to 345 s pulsations in the X-ray flux of SAX J0103.2-7209. The BeppoSAX X-ray spectrum is well fitted by an absorbed power law with a photon index of similar to 1.0 plus a blackbody component with kT = 0.11 keV. The unabsorbed luminosity in the 2-10 keV energy range is similar to 1.2 x 10(36) ergs s(-1). In a very recent Chandra observation, the 345 s pulsations are also detected. The available period measurements provide a constant period derivative of -1.7 s yr(-1) over the last 3 years, making SAX J0103.2-7209 one of the most rapidly spinning up X-ray pulsars known. The BeppoSAX position (30 " uncertainty radius) is consistent with that of the Einstein source 2E 0101.5-7225 and the ROSAT source RX J0103.2-7209. This source was detected at a luminosity level of a few times 10(35)-10(36) ergs s(-1) in all data sets of past X-ray missions since 1979. The ROSAT HRI and Chandra positions are consistent with that of a m(v) = 14.8 Be spectral-type star already proposed as the likely optical counterpart of 2E 0101.5-7225. We briefly report and discuss photometric and spectroscopic data carried out at the ESO telescopes 2 days before the BeppoSAX observation. We conclude that SAX J0103.2-7209 and 2E 0101.5-7225 are the same source: a relatively young and persistent X-ray pulsar in the SMC. C1 Osservatorio Astron Roma, I-00040 Monte Porzio Catone, Roma, Italy. Osservatorio Astorn Brera, I-23807 Merate, Italy. CNR, Inst Tecnol & Studio Radiazioni Extraterrestri, I-40129 Bologna, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CNR, Ist Ric Fis Cosm & Tecnol Relative, I-20133 Milan, Italy. Estec, Dept ESA, Div Astrophys, NL-2200 AG Noordwijk, Netherlands. Agenzia Spaziale Italiana, SAX Sci Data Ctr, I-00198 Rome, Italy. RP Israel, GL (reprint author), Osservatorio Astron Roma, Via Frascati 33, I-00040 Monte Porzio Catone, Roma, Italy. RI Orlandini, Mauro/H-3114-2014 OI Orlandini, Mauro/0000-0003-0946-3151 NR 22 TC 18 Z9 18 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 2000 VL 531 IS 2 BP L131 EP L134 DI 10.1086/312546 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 299MC UT WOS:000086201500012 ER PT J AU Allan, JF Simkin, T AF Allan, JF Simkin, T TI Fernandina Volcano's evolved, well-mixed basalts: Mineralogical and petrological constraints on the nature of the Galapagos plume SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Review ID SPREADING CENTER SYSTEM; PUU-OO ERUPTION; SCIENTIFIC DRILLING PROJECT; MIGRATING MIDOCEAN RIDGES; LAMONT SEAMOUNT CHAIN; MANTLE PLUME; KILAUEA VOLCANO; PETROGENETIC INDICATORS; MAJOR-ELEMENT; THERMODYNAMIC PROPERTIES AB Fernandina Volcano, the most active of Galapagos volcanoes and the one most directly overlying the Galapagos hotspot, is one of a small number of active, plume-related oceanic island volcanoes with a well-documented recent eruptive record. Whole rock and glass analyses of lava and tephra from all 12 known eruptions from 1958 to the present show them to be evolved (Mg # (= Mg/Mg + Fe2+) of 0.47-0.56), plagioclase-phyric, clinopyroxene- and olivine-bearing tholeiites. Thermodynamic modeling indicates that this phase assemblage erupted at 1100-1130 degrees C and is stable only at low pressures (less than or equal to 0.1-0.2 GPa), thereby representing crystallization within a shallow magma chamber underlying the well-defined, 850-m-deep, 5 by 6.5 km caldera. These tholeiites are remarkably homogenous, as is shown by narrow ranges in Zr/Y (5.7-6.3), (La/Sm)(N) (1.4-1.7), and (La/Yb)(N) (3.8-4.3). Prehistoric Fernandina lavas, selected for petrographic and geographic variation over the entire subaerial volcano, are of remarkably similar composition (e.g., Zr/Y is 5.2-6.1, (La/Sm)(N) is 1.5-1.6, and (La/Yb)(N) is 3.4-4.1), with a single example of a more primitive lava having an Mg # of 0.63, with 8.5% FeO at 8% MgO. Cr-spinel and glass melt inclusions in plagioclase, together with zoned olivine, give evidence for a range of parental melts in the recent shallow magmatic system, with Mg # as high as 0.62. Extensive, shallow magma mixing is required to explain these variations in mineral and inclusion chemistry, indicating more thermal variation within the shallow magmatic system than is implied by the relatively monotonous whole rock compositions. Apparently, Fernandina's shallow magma chamber has physically blocked passage of more primitive magmas to the surface and homogenized the erupted lavas by extensive mixing. Small variations in lava isotopic and compatible element composition, combined with the need to resupply melt to maintain thermal balance, indicate that replenishment of the magma chamber is semicontinuous, with resupply occurring of the order of a decade or less. Plagioclase-dominated, evolved Fernandina lavas are in sharp contrast to more primitive, olivine-dominated Hawaiian lavas; the total lack of primitive melts in the shallow Fernandina magmatic system implies that substantial fractionation and heat loss occurred during melt transportation from the mantle source to the edifice magma chamber, despite the fact that these melts were transported through relatively warm, young, and thin lithosphere adjacent to the Cocos-Nazca ridge. The diffuse nature of Galapagos volcanism, with 20th century eruptions from eight distinct volcanoes over a 20,000 km(2) area, further supports this interpretation and suggests that the Galapagos plume is relatively diffuse, weak, and significantly less thermally intense than the vigorous Hawaiian plume. It may in fact be waning. C1 Texas A&M Univ, Dept Geol & Geophys, College Stn, TX USA. Smithsonian Inst, Dept Mineral Sci, Washington, DC 20560 USA. RP Allan, JF (reprint author), Natl Sci Fdn, Ocean Drilling Program, 4201 Wilson Blvd, Arlington, VA 22230 USA. EM jallan@nsf.gov; simkin@nmnh.si.edu NR 120 TC 33 Z9 33 U1 2 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAR 10 PY 2000 VL 105 IS B3 BP 6017 EP 6041 DI 10.1029/1999JB900417 PG 25 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 292AV UT WOS:000085772700026 ER PT J AU Derevianko, A Hemmers, O Oblad, S Glans, P Wang, H Whitfield, SB Wehlitz, R Sellin, IA Johnson, WR Lindle, DW AF Derevianko, A Hemmers, O Oblad, S Glans, P Wang, H Whitfield, SB Wehlitz, R Sellin, IA Johnson, WR Lindle, DW TI Electric-octupole and pure-electric-quadrupole effects in soft-X-ray photoemission SO PHYSICAL REVIEW LETTERS LA English DT Article ID ANGULAR-DISTRIBUTION PARAMETERS; APPROXIMATION; PHOTOIONIZATION AB Second-order [O(k(2)), k = omega/c] nondipole effects in soft-x-ray photoemission are demonstrated via an experimental and a theoretical study of angular distributions of neon valence photoelectrons in the 100-1200 eV photon-energy range. A newly derived theoretical expression for nondipolar angular distributions characterizes the second-order effects using four new parameters with primary contributions from pure-quadrupole and octupole-dipole interference terms;Independent-particle calculations of these parameters account for a significant portion of the existing discrepancy between experiment and theory for Ne 2p first-order nondipole parameters. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. Stockholm Univ, S-10405 Stockholm, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Univ Wisconsin, Dept Phys, Eau Claire, WI 54702 USA. Univ Wisconsin, Ctr Synchrotron Radiat, Stoughton, WI 53589 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Derevianko, A (reprint author), Harvard Smithsonian Ctr Astrophys, ITAMP, 60 Garden St, Cambridge, MA 02138 USA. RI Derevianko, Andrei/G-8356-2011 NR 16 TC 69 Z9 72 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 MAR 6 PY 2000 VL 84 IS 10 BP 2116 EP 2119 DI 10.1103/PhysRevLett.84.2116 PG 4 WC Physics, Multidisciplinary SC Physics GA 289YT UT WOS:000085650100017 ER PT J AU Hou, YM Potts, R Yuan, BY Guo, ZT Deino, A Wang, W Clark, J Xie, GM Huang, WW AF Hou, YM Potts, R Yuan, BY Guo, ZT Deino, A Wang, W Clark, J Xie, GM Huang, WW TI Mid-Pleistocene Acheulean-like stone technology of the Bose basin, South China SO SCIENCE LA English DT Article ID CHRONOLOGY; OLDOWAN; ASIA AB Stone artifacts from the Bose basin, South China, are associated with tektites dated to 803,000 +/- 3000 years ago and represent the oldest known Large cutting tools (LCTs) in East Asia. Bose toolmaking is compatible with Mode 2 (Acheulean) technologies in Africa in its targeted manufacture and biased spatial distribution of LCTs, Large-scale flaking, and high flake scar counts. Acheulean-Like tools in the mid-Pleistocene of South China imply that Mode 2 technical advances were manifested in East Asia contemporaneously with handaxe technology in Africa and western Eurasia. Bose Lithic technology is associated with a tektite airfall and forest burning. C1 Smithsonian Inst, Natl Museum Nat Hist, Human Origins Program, Washington, DC 20560 USA. Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Beijing 100044, Peoples R China. Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China. Berkeley Geochronol Ctr, Berkeley, CA 94709 USA. Nat Hist Museum Guangxi Zhuang Autonomous Reg, Nanning 530012, Peoples R China. Hist Museum Guangxi Zhuang Autonomous Reg, Nanning 530022, Peoples R China. RP Potts, R (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Human Origins Program, Washington, DC 20560 USA. RI Guo, Zhengtang/B-6854-2008 OI Guo, Zhengtang/0000-0003-2259-9715 NR 47 TC 137 Z9 182 U1 3 U2 23 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 MAR 3 PY 2000 VL 287 IS 5458 BP 1622 EP 1626 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 289NE UT WOS:000085628200029 ER PT J AU Cohn, JD Stewart, ED AF Cohn, JD Stewart, ED TI Non-abelian discrete gauge symmetries and inflation SO PHYSICS LETTERS B LA English DT Article ID LARGE-SCALE STRUCTURE; HYBRID INFLATION; DENSITY PERTURBATIONS; NATURAL INFLATION; ENTROPY CRISIS; SUPERSYMMETRY; SUPERGRAVITY AB Obtaining a potential flat enough to provide slow roll inflation is often difficult when gravitational effects are included. Non-abelian discrete gauge symmetries can guarantee the flatness of the inflaton potential in this case, and also provide special field values where inflation can end. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Fermi Natl Accelerator Lab, NASA, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. Korea Adv Inst Sci & Technol, Dept Phys, Taejon 305701, South Korea. RP Cohn, JD (reprint author), Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. RI Stewart, Ewan/C-1565-2011 NR 23 TC 18 Z9 18 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 2 PY 2000 VL 475 IS 3-4 BP 231 EP 235 DI 10.1016/S0370-2693(00)00089-7 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 291LF UT WOS:000085735100005 ER PT J AU Geary, CM AF Geary, CM TI Gilbert D. Schneider 1920-1999 - Obituary SO AFRICAN ARTS LA English DT Biographical-Item C1 Smithsonian Inst, Washington, DC 20560 USA. RP Geary, CM (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CALIF PI LOS ANGELES PA AFRICAN STUDIES CNTR, LOS ANGELES, CA 90024 USA SN 0001-9933 J9 AFR ARTS JI Afr. Arts PD SPR PY 2000 VL 33 IS 1 BP 17 EP 17 PG 1 WC Art SC Art GA 334AQ UT WOS:000088163300005 ER PT J AU Sakai, S Kato, M Nagamasu, H AF Sakai, S Kato, M Nagamasu, H TI Artocarpus (Moraceae) - Gall midge pollination mutualism mediated by a male-flower parasitic fungus SO AMERICAN JOURNAL OF BOTANY LA English DT Article DE Borneo; gall midge; Lambir; monoecy; Moraceae; Mucorales; pollination ID REPRODUCTIVE ECOLOGY; USTILAGO-VIOLACEA; WIND-POLLINATION; MIMICRY; FIG; EVOLUTION; BIOLOGY; FOREST; SYSTEM AB A previously undescribed pollination system involving a monoecious tree species, Artocarpus integer (Moraceae), pollinator gall midges, and fungi is reported from a mixed dipterocarp forest in Sarawak, Borneo. The fungus Choanephora sp. (Choanephoraceae, Mucorales, Zygomycetes) infects male inflorescences of A. integer, and gall midges (Contarinia spp., Cecidomyiinae, Diptera) feed on the fungal mycelia and oviposit on the inflorescence. Their larvae also feed on the mycelia and pupate in the inflorescence. The gall midges are also attracted by female inflorescences lacking mycelia, probably due to a floral fragrance similar to that of male inflorescences. Because of the sticky pollen, dominance of Contarinia spp. in flower visitors, and pollen load observed on Contarinia spp. collected on both male and female inflorescences, Artocarpus integer is thought to be pollinated by the gall midges. Although several pathogenic fungi have been reported to have interactions with pollinators, this is the first report on a pollination mutualism in which a fungus plays an indispensable role. The pollination system described here suggests that we should be more aware of the roles fungi can play in pollinations. C1 Kyoto Univ, Ctr Ecol Res, Kyoto 6068502, Japan. Kyoto Univ, Grad Sch Human & Environm Studies, Kyoto 6068501, Japan. Kyoto Univ Museum, Kyoto 6068501, Japan. RP Sakai, S (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 38 TC 21 Z9 25 U1 1 U2 10 PU BOTANICAL SOC AMER INC PI COLUMBUS PA OHIO STATE UNIV-DEPT BOTANY 1735 NEIL AVE, COLUMBUS, OH 43210 USA SN 0002-9122 J9 AM J BOT JI Am. J. Bot. PD MAR PY 2000 VL 87 IS 3 BP 440 EP 445 DI 10.2307/2656640 PG 6 WC Plant Sciences SC Plant Sciences GA 295FT UT WOS:000085956600016 PM 10719005 ER PT J AU Engelbrecht, BMJ Velez, V Tyree, MT AF Engelbrecht, BMJ Velez, V Tyree, MT TI Hydraulic conductance of two co-occuring neotropical understory shrubs with different habitat preferences SO ANNALS OF FOREST SCIENCE LA English DT Article DE hydraulic conductance; drought; Piper; tropical rainforest; understory shrub ID WATER RELATIONS; ACER-SACCHARUM; TROPICAL FORESTS; LIGHT REGIMES; WOODY-PLANTS; ARCHITECTURE; TREES; ROOT; VULNERABILITY; RESISTANCE AB Whole plant hydraulic conductance was measured for two co-occuring neotropical rainforest understory shrub species of the genus Piper, which differ in their habitat preference with respect to soil moisture: P, trigonum is restricted to wet habitats, whereas P. cordulatum occurs in drier sites. Plants were grown under four treatments (two light conditions crossed with two watering regimes), representing the extremes of conditions in their natural habitat. The data showed significantly higher total hydraulic conductance and leaf specific conducance in the drought-avoiding species, P. trigonum, than in the drought-tolerant species P. cordulatum. The measured parameters also differed between growth treatments. The species differences in hydraulic conductance could be interpreted as adaptive in the respective species' habitat, and might thus be important in determining habitat preference and distribution of the two species. C1 Tech Univ Darmstadt, Inst Bot, D-64287 Darmstadt, Germany. Smithsonian Trop Res Inst, Balboa, Panama. US Forest Serv, USDA, Aiken Forestry Sci Lab, S Burlington, VT 05402 USA. RP Engelbrecht, BMJ (reprint author), Tech Univ Darmstadt, Inst Bot, Schnittspahnstr 3-5, D-64287 Darmstadt, Germany. RI Engelbrecht, Bettina/E-9914-2012 NR 30 TC 27 Z9 28 U1 0 U2 8 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 1286-4560 J9 ANN FOR SCI JI Ann. For. Sci. PD MAR-APR PY 2000 VL 57 IS 3 BP 201 EP 208 PG 8 WC Forestry SC Forestry GA 315NP UT WOS:000087120100001 ER PT J AU Briceno, RD Eberhard, WG AF Briceno, RD Eberhard, WG TI Possible Fisherian changes in female mate-choice criteria in a mass-reared strain of Ceratitis capitata (Diptera: Tephritidae) SO ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA LA English DT Article DE Mediterranean fruit fly; Ceratitis capitata; Fisherian sexual selection; courtship; mass-rearing ID FRUIT-FLY DIPTERA; SUCCESS AB The frequent interruption of male courtship in highly crowded mass-rearing cages of Ceratitis capitata (Wiedemann) was correlated with changes in both male courtship and female acceptance criteria in a mass-reared Costa Rican strain, in accord with previous studies of other strains. Abbreviation of courtship behavior by mass-reared males was associated with the loss of the wild-type female tendency to reject males that performed shorter courtships. Consideration of probable costs and benefits of female choice in mass-rearing cages suggests that inadvertant selection in the cages probably favored the change in female criteria because females obtained sons with more effective courlship behavior. C1 Univ Costa Rica, Escuela Biol, Smithsonian Trop Res Inst, San Jose, Costa Rica. RP Briceno, RD (reprint author), Univ Costa Rica, Escuela Biol, Smithsonian Trop Res Inst, Ciudad Univ, San Jose, Costa Rica. NR 17 TC 11 Z9 11 U1 0 U2 2 PU ENTOMOL SOC AMER PI LANHAM PA 9301 ANNAPOLIS RD, LANHAM, MD 20706 USA SN 0013-8746 J9 ANN ENTOMOL SOC AM JI Ann. Entomol. Soc. Am. PD MAR PY 2000 VL 93 IS 2 BP 343 EP 345 DI 10.1603/0013-8746(2000)093[0343:PFCIFM]2.0.CO;2 PG 3 WC Entomology SC Entomology GA 359VB UT WOS:000089631800025 ER PT J AU Tonry, JL Kochanek, CS AF Tonry, JL Kochanek, CS TI Redshifts of the gravitational lenses MG 1131+0456 and B1938+666 SO ASTRONOMICAL JOURNAL LA English DT Article DE distance scale; gravitational lensing ID EINSTEIN RING; MG-1131+0456; MG1131+0456; GALAXIES; IMAGES AB The redshifts of the gravitational lens galaxies in MG 1131 + 0456 and B1938 + 666 are 0.844 and 0.881, respectively. Both are early-type galaxies lying at the redshifts predicted by assuming that they are early-type galaxies with old stellar populations lying on the fundamental plane. We also find evidence for a foreground group of galaxies at z = 0.343 near MG 1131 + 0456. The source redshifts are predicted to be greater than or similar to 1.8 in both systems, but they are so red that infrared spectra will be required to determine their redshifts. C1 Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Tonry, JL (reprint author), Univ Hawaii, Inst Astron, 2680 Woodlawn Dr, Honolulu, HI 96822 USA. NR 25 TC 33 Z9 35 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAR PY 2000 VL 119 IS 3 BP 1078 EP 1082 DI 10.1086/301273 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297CA UT WOS:000086062900003 ER PT J AU Terndrup, DM Stauffer, JR Pinsonneault, MH Sills, A Yuan, YQ Jones, BF Fischer, D Krishnamurthi, A AF Terndrup, DM Stauffer, JR Pinsonneault, MH Sills, A Yuan, YQ Jones, BF Fischer, D Krishnamurthi, A TI Rotational velocities of low-mass stars in the Pleiades and Hyades SO ASTRONOMICAL JOURNAL LA English DT Article DE open clusters and associations : individual (Pleiades, Hyades); stars : magnetic fields; stars : rotation ID SOLAR-TYPE STARS; T-TAURI STARS; MAIN-SEQUENCE STARS; PROPER-MOTION MEMBERSHIP; ALPHA-PERSEI CLUSTER; LITHIUM DEPLETION; ANGULAR-MOMENTUM; M-DWARF; CHROMOSPHERIC ACTIVITY; RADIAL-VELOCITIES AB We have obtained high-resolution spectra of 89 M dwarf members of the Pleiades and Hyades and have derived radial velocities, Ha equivalent widths, and spectroscopic rotational velocities for these stars. Typical masses of the newly observed Pleiades and Hyades stars are similar to 0.4 M. and similar to 0.2 M., respectively. We combine our new observations with previously published data to explore the rotational evolution of young stars with M less than or equal to 0.4 M.. The average rotation rate in the Hyades (age 600 Myr) is about 0.4 times that in the Pleiades (110 Myr), and the mean equivalent widths of H alpha are also lower. As found in previous studies, the correlation between rotation and chromospheric activity is identical in both clusters, implying that the lower activity in the Hyades is a result of the lower rotation rates. We show that a simple scaling of the Pleiades rotational distribution for M less than or equal to 0.4 M., corrected for the effects of structural evolution, matches that of the Hyades if the average angular momentum loss from the Pleiades to the Hyades age is factor of approximate to 6. This suggests that the distribution of initial angular momenta and disk-locking lifetimes for the lowest mass stars was similar in both clusters. We argue that this result provides further evidence for a saturation of the angular momentum loss rate at high rotational velocities. C1 Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Calif Santa Cruz, Lick Observ, Board Studies Astron & Astrophys, Santa Cruz, CA 95064 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80303 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Terndrup, DM (reprint author), Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. OI Fischer, Debra/0000-0003-2221-0861 NR 94 TC 84 Z9 84 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAR PY 2000 VL 119 IS 3 BP 1303 EP 1316 DI 10.1086/301259 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297CA UT WOS:000086062900023 ER PT J AU Zhang, Q Ho, PTP Wright, MCH AF Zhang, Q Ho, PTP Wright, MCH TI The SiO and CS emission in the molecular outflow toward L1157 SO ASTRONOMICAL JOURNAL LA English DT Article DE ISM : clouds; ISM : individual(L1157); ISM : jets and outflows; stars : formation ID YOUNG BIPOLAR OUTFLOWS; DARK CLOUD; CHEMISTRY; AMMONIA; L-1157; SHOCKS; JET; GAS AB We present observational studies of the molecular outflow associated with the Class 0 young stellar object toward L1157. The CO emission shows a well-collimated bipolar morphology with rich structure. In addition to the extended emission, the CO gas is found in clumps in the vicinity of the near-infrared H-2 emission. The SiO emission is seen in six prominent condensations, three on each side of the protostar. They appear to be in three pairs; each pair aligns well with the exciting star. The CS emission imaged toward the blueshifted outflow is well collimated and presents a bow-shaped structure coincident with the SiO and H-2. A comparison of the outflow in different tracers suggests that the molecular gas is entrained at the head of an underlying jet. The jet seems to be episodic and shows signs of deceleration as it ploughs through the dense core. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA. RP Zhang, Q (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 23 TC 31 Z9 32 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAR PY 2000 VL 119 IS 3 BP 1345 EP 1351 DI 10.1086/301274 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297CA UT WOS:000086062900027 ER PT J AU Lacy, CHS Torres, G Claret, A Stefanik, RP Latham, DW Sabby, JA AF Lacy, CHS Torres, G Claret, A Stefanik, RP Latham, DW Sabby, JA TI Absolute properties of the eclipsing binary star FS monocerotis SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : eclipsing; binaries : spectroscopic; stars : evolution; stars : fundamental parameters; stars : individual (FS Monocerotis) ID SPECTROSCOPIC BINARIES; RADIAL-VELOCITIES; STELLAR MODELS; UBV; MASSES; UVBY AB We present photometric observations in B and V as well as spectroscopic observations of the 1.9 day-period, double-lined main-sequence eclipsing binary FS Mon. From the analysis of the light curves and radial velocity curves, we have determined the masses and radii of the components: 1.631 +/- 0.012 M. and 2.051 +/- 0.012 R. for the primary component; 1.461 +/- 0.010 M. and 1.629 +/- 0.012 R. for the secondary component. The formal uncertainties are all less than 1%. Based on our light curves as well as on the combined-light photometry of the system, we estimate effective temperatures of 6715 +/- 100 K for the primary and 6550 +/- 100 K for the secondary component, corresponding to spectral types of F2 and F4, respectively. Projected rotational velocities (upsilon sin i) from the spectograms are measured as 52 +/- 2 km s(-1) and 43 +/- 3 km s(-1), respectively, from the spectrograms and are consistent with rotation that is synchronous with the orbital motion. Evolutionary tracks from current models are in good agreement with the observations for a system age of about 1.6 x 10(9) yr with slightly nonsolar chemical composition. We find the best match for models with a slightly lower helium abundance and a higher metal abundance than the Sun. An accurate metallicity determination for FS Mon is needed to constrain the models further. C1 Univ Arkansas, Dept Phys, Fayetteville, AR 72701 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. RP Lacy, CHS (reprint author), Univ Arkansas, Dept Phys, Fayetteville, AR 72701 USA. NR 48 TC 19 Z9 19 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAR PY 2000 VL 119 IS 3 BP 1389 EP 1397 DI 10.1086/301272 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297CA UT WOS:000086062900032 ER PT J AU van den Ancker, ME Wesselius, PR Tielens, AGGM AF van den Ancker, ME Wesselius, PR Tielens, AGGM TI ISO spectroscopy of young intermediate-mass stars in the BD+40 degrees 4124 group SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE shock waves; stars : circumstellar matter; stars : formation; ISM : HII regions; ISM : jets and outflows; infrared : stars ID HERBIG-AE/BE STARS; RADIO-CONTINUUM EMISSION; ORION POPULATION STARS; AE-BE STARS; MOLECULAR CLOUDS; LINE EMISSION; PHOTODISSOCIATION REGIONS; WAVELENGTH SPECTROMETER; INFRARED-EMISSION; FORMING REGIONS AB We present the results of ISO SWS and LWS grating scans towards the three brightest members of the BD+40 degrees 4124 group in the infrared: BD+40 degrees 4124 (B2Ve), LkH alpha 224 (A7e) and the embedded source LkH alpha 225. Emission from the pure rotational lines of H-2. from re-vibrational transitions of CO. from PAHs. from H I recombination lines and from the infrared line structure lines of [Fe II], [Si II], [S I], [O I], [O III] and [C III was detected. These emission lines arise in the combination of a low-density (approximate to 10(2) cm(-3)) H II region with a clumpy PDR in the case of BD+40 degrees 4124. The lower transitions of the infrared H I lines observed in BD+40 degrees 4124 are optically thick: most likely they arise in either a dense wind or a circumstellar disk. This same region is also responsible for the optical H1 lines and the radio continuum emission. In the lines of sight towards LkH alpha 224 and LkH alpha 225, the observed emission lines arise in a non-dissociative shock produced by a slow (approximate to 20 km s(-1)) outflow arising from LkHa 225. Toward LkH alpha 225 WE also observe a dissociative shock, presumably located closer to the outflow source than the non-dissociative shock. Tn the line of sight towards LkH alpha 225 we observed absorption features due to solid water ice and amorphous silicates, and due to gas-phase H2O, CO and CO2. No solid CO2 was detected towards LkH alpha 225. making this the first line of sight where the bulk of the CO2 is in the gas-phase. C1 Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. SRON, NL-9700 AV Groningen, Netherlands. Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. EM mario@astro.uva.nl NR 89 TC 23 Z9 23 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAR PY 2000 VL 355 IS 1 BP 194 EP 210 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 303ZR UT WOS:000086458500027 ER PT J AU Flaccomio, E Micela, G Sciortino, S Damiani, F Favata, F Harnden, FR Schachter, J AF Flaccomio, E Micela, G Sciortino, S Damiani, F Favata, F Harnden, FR Schachter, J TI HRI observations of PMS stars in NGC 2264 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : coronae; stars : formation; stars : luminosity function, mass function; stars : pre-main sequence; Galaxy : open clusters and associations : individual : NGC 2264; X-rays : stars ID OPEN CLUSTER NGC-2264; T-TAURI STARS; ROSAT X-RAY; EINSTEIN OBSERVATIONS; DARK CLOUD; REGION; PHOTOMETRY; EMISSION; PLEIADES; FLARE AB We analyze six ROSAT HRI observations pointed toward the Star Forming Region (SFR) NGC 2264. Three are pointed to the southern star formation core, the other three about 20' to the north. We detect 169 X-ray sources, similar to 95% of which are likely to be Pre Main Sequence (PMS) stars, significantly enlarging the known population of the SFR in the area covered by the observations. Using published BVRI photometry we place the X-ray sources with well defined optical counterparts on the HRI diagram and estimate their masses and ages. Our comparison of the mass function and age distribution of the X-ray sources with results previously obtained for NGC 2264, demonstrates that deep X-ray observations provide, at least in this case, a very efficient method of selecting SFR members and does not introduce stronger biases than other methods. Since the observation cover a time span of similar to 5 years, we are able to study in detail the X-ray variability of our sample of PMS stars. We find that: 1) a large fraction of our sources are variable on several time scales and 2) Classical T Tauri Systems (i.e. stars surrounded by disks) are significantly more variable than the rest of our sample, suggesting a role of accretion disks in the emission and/or in the absorption of the X-ray radiation. C1 Univ Palermo, Dipartimento Sci Fis & Aston, I-90133 Palermo, Italy. Osservatorio Astron Palermo GS Vaiana, I-90134 Palermo, Italy. European Space Agcy, Estec, Dept Space Sci, Div Astrophys, NL-2200 AG Noordwijk, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Flaccomio, E (reprint author), Univ Palermo, Dipartimento Sci Fis & Aston, I-90133 Palermo, Italy. EM ettoref@oapa.astropa.unipa.it OI Flaccomio, Ettore/0000-0002-3638-5788; Damiani, Francesco/0000-0002-7065-3061 NR 45 TC 36 Z9 36 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAR PY 2000 VL 355 IS 2 BP 651 EP 667 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 311DF UT WOS:000086869000027 ER PT J AU Unger, SJ Clegg, PE Stacey, GJ Cox, P Fischer, J Greenhouse, M Lord, SD Luhman, ML Satyapal, S Smith, HA Spinoglio, L Wolfire, M AF Unger, SJ Clegg, PE Stacey, GJ Cox, P Fischer, J Greenhouse, M Lord, SD Luhman, ML Satyapal, S Smith, HA Spinoglio, L Wolfire, M TI ISO-LWS spectroscopy of Centaurus A: extended star formation SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : individual : Centaurus A = NGC 5128; infrared : galaxies; galaxies : ISM; galaxies : starburst; galaxies : active ID H-II REGIONS; INTERSTELLAR-MEDIUM; EMISSION; NGC-5128; GALAXY; EXCITATION; ORIGIN; N/O AB We present the first full FIR spectrum of Centaurus A (NGC 5128) from 43 - 196.7 mu m. The data was obtained with the ISO Long Wavelength Spectrometer (LWS). We conclude that the FIR emission in a 70 " beam centred on the nucleus is dominated by star formation rather than AGN activity. The flux in the far-infrared lines is similar to 1% of the total FIR: the [C II] line flux is similar to 0.4% FIR and the [O I] line is similar to 0.2%, with the remainder arising from [O III], [N II] and [N III] lines. These are typical values for starburst galaxies. The ratio of the [N III] / [N II] line intensities from the HII regions in the dust lane corresponds to an effective temperature, T-eff similar to 35 500 K, implying that the tip of the main sequence is headed by 08.5 stars and that the starburst is similar to 6 x 10(6) years old. This suggests that the galaxy underwent either a recent merger or a merger which triggered a series of bursts. The N/O abundance ratio is consistent with the range of similar to 0.2 - 0.3 found for Galactic HII regions. We estimate that < 5% of the observed [C II] arises in the cold neutral medium (CNM) and that similar to 10% arises in the warm ionized medium (WIM). The main contributors to the [C II] emission are the PDRs, which are located throughout the dust lane and in regions beyond where the bulk of the molecular material lies. On scales of similar to 1 kPc the average physical properties of the PDRs are modelled with a gas density, n similar to 10(3) cm(-3) an incident far-UV field, G similar to 10(2) times the local Galactic field, and a gas temperature of similar to 250 K. C1 Univ London Queen Mary & Westfield Coll, Dept Phys, London E1 4NS, England. Cornell Univ, Ithaca, NY USA. Inst Astrophys Spatiale, Orsay, France. USN, Res Lab, Washington, DC 20375 USA. NASA Goddard, Greenbelt, MD USA. CALTECH, IPAC, Pasadena, CA USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CNR, Ist Fis Spazio Interplanetario, Rome, Italy. Univ Maryland, College Pk, MD 20742 USA. RP Unger, SJ (reprint author), Univ London Queen Mary & Westfield Coll, Dept Phys, Mile End Rd, London E1 4NS, England. EM s.j.unger@qmw.ac.uk OI Spinoglio, Luigi/0000-0001-8840-1551 NR 28 TC 33 Z9 33 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAR PY 2000 VL 355 IS 3 BP 885 EP 890 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 311DG UT WOS:000086869100010 ER PT J AU Colomer, F Reid, MJ Menten, KM Bujarrabal, V AF Colomer, F Reid, MJ Menten, KM Bujarrabal, V TI The spatial and velocity structure of circumstellar water masers SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE masers; techniques : interferometric; stars : circumstellar matter; stars : late-type ID LATE-TYPE STARS; MASS-LOSS RATES; EVOLVED STARS; INTERFEROMETRIC OBSERVATIONS; H2O MASERS; MERLIN OBSERVATIONS; SIO MASERS; EMISSION; DISTRIBUTIONS; ENVELOPES AB We report observations with the VLA of 22 GHz H2O maser emission in the circumstellar envelopes of 11 late-type stars. We model the maser emission towards six of them (IRC +60169, R Crt, U Her, RX Boo, R LMi, and R Gas) with a computer program we have developed, that fits three-dimensional Gaussian sources (in position and velocity) to the measured intensity distribution. This approach to the problem is superior to the standard procedure of fitting two-dimensional Gaussian models to images for each frequency channel, and it is shown to be a powerful method of identifying blended and/or weak maser features. As a result, we find that the H2O maser emission is located in a thin shell expanding from the star in four cases, despite of the fact that the emission is clumpy and the shells appear incomplete. Moreover, our maps indicate that the H2O maser emission comes from inner parts of the circumstellar envelope, which are comparable in extent to the regions in which dust grains form and in which the expanding envelope has not reached its terminal velocity. Our analysis also provides the spectral linewidth of each maser feature, which contains information about the physical conditions in the emitting region. In particular, it provides a tool to discriminate whether or not these masers are saturated as, for unsaturated masers, theory predicts that a correlation between the strongest features and the narrowest linewidths should exist. This behaviour is found in at least U Her, RX Boo, and R Cas. C1 Observ Astron Nacl IGN, Alcala De Henares 28800, Spain. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Max Planck Inst Radioastron, D-53121 Bonn, Germany. RP Colomer, F (reprint author), Observ Astron Nacl IGN, Alcala De Henares 28800, Spain. EM colomer@oan.es NR 40 TC 29 Z9 29 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAR PY 2000 VL 355 IS 3 BP 979 EP 993 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 311DG UT WOS:000086869100018 ER PT J AU Haiman, Z Menou, K AF Haiman, Z Menou, K TI On the cosmological evolution of the luminosity function and the accretion rate of quasars SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; cosmology : theory; quasars : general ID BLACK-HOLES; GALACTIC NUCLEI; GALAXY; DISKS; OBJECTS; MODELS; POPULATION; UNIVERSE AB We consider a class of models for the redshift evolution (between 0 less than or similar to z less than or similar to 4) of the observed optical and X-ray quasar luminosity functions (LFs), with the following assumptions: (1) the mass function of dark matter halos follows the Press-Schechter theory, (2) the black hole (BH) mass scales linearly with the halo mass, (3) quasars have a constant universal lifetime, and (4) a thin accretion disk provides the optical luminosity of quasars, while the X-ray/optical flux ratio is calibrated from a sample of observed quasars. The mass accretion rate, hi, onto quasar BHs is a free parameter of the models, which we constrain using the observed LFs. The accretion rate M inferred from either the optical or X-ray data under these assumptions generally decreases as a function of cosmic time from z similar or equal to 4 to z similar or equal to 0. We find that a comparable accretion rate is inferred from the X-ray and optical LF only if the X-ray/optical flux ratio decreases with BH mass. Near z similar or equal to 0, M drops to substantially sub-Eddington values at which advection-dominated accretion flows (ADAFs) exist. Such a decline of hi, possibly followed by a transition to radiatively inefficient ADAFs, could explain both the absence of bright quasars in the local universe and the faintness of accreting BHs at the centers of nearby galaxies. Vile argue that a decline of the accretion rate of the quasar population is indeed expected in cosmological structure formation models. C1 NASA, Fermi Natl Accelerator Lab, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Observ Paris, CNRS, DARC, F-92195 Meudon, France. RP Haiman, Z (reprint author), NASA, Fermi Natl Accelerator Lab, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. EM zoltan@fnal.gov; kmenou@cfa.harvard.edu NR 61 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 J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2000 VL 531 IS 1 BP 42 EP 51 DI 10.1086/308468 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297WM UT WOS:000086105700005 ER PT J AU Stark, G Huber, KP Yoshino, K Chan, MC Matsui, T Smith, PL Ito, K AF Stark, G Huber, KP Yoshino, K Chan, MC Matsui, T Smith, PL Ito, K TI Line oscillator strength measurements in the 0-0 band of the c '(4) (1)Sigma(+)(u) <- X-1 Sigma(+)(g) transition of N-2 SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : molecules; molecular data; planets and satellites : general ultraviolet : general ID VUV SPECTROSCOPIC FACILITY; HIGH-RESOLUTION; CROSS-SECTIONS; ABSORPTION-SPECTRUM; MOLECULAR NITROGEN; UPPER-ATMOSPHERE; RYDBERG STATES; N2; EMISSION; PHOTOABSORPTION AB Oscillator strengths for 48 rotational lines in the 0-0 band of the c(4)' (1)(u)Sigma(+) <-- X-1 (g)Sigma(+) transition of N-14(2), a prominent feature in planetary airglow emissions, have been determined from vacuum ultraviolet photoabsorption spectra recorded with an instrumental resolution of similar to 6.5 x 10(-4) nm (resolving power approximate to 150,000). The sum of the integrated cross sections over all measured lines, including six lines appearing on account of a local perturbation by v = 1 of the b' state, yields a room temperature band f-value of 0.136 +/- 0.020. This result is compared with earlier measurements of band-integrated absorption cross sections and with a study of electron-impact-induced emission from c(4)'(0), as well as with electron scattering measurements and a nonadiabatic calculation of vibronic band strengths. The relative P- and R-branch absorption intensities deviate systematically from those of an unperturbed (1)Sigma <-- (1)Sigma band, as expected from the interactions of the c(4)' (v = 0) level with nearby Rydberg and valence states. In addition, the variation of the band f-values derived from pairs of R- and P-branch transitions with a common lower-state rotational level, f(J "), are found to be J-dependent, indicating that the f-value obtained from the band-integrated absorption cross section is slightly temperature dependent. The J-dependence off(J ") is briefly discussed in the context of the interference patterns which characterize the absorption strengths in the region of the widespread interactions between Rydberg and valence state levels. C1 Wellesley Coll, Dept Phys, Wellesley, MA 02481 USA. Ibaraki Univ, Fac Sci, Inst Astrophys & Planetary Sci, Mito, Ibaraki 3108512, Japan. Natl Res Council Canada, Steacie Inst Mol Sci, Ottawa, ON K1A 0R6, Canada. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Chinese Univ Hong Kong, Dept Chem, Shatin, Hong Kong, Peoples R China. Hiroshima Univ, Hiroshima Synchrotron Radiat Ctr, Higashihiroshima 7398526, Japan. CURSOAR Technol, Watertown, MA 02171 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. High Energy Accelerator Res Org, Inst Mat Struct Sci, Photon Factory, Tsukuba, Ibaraki 3050801, Japan. RP Stark, G (reprint author), Wellesley Coll, Dept Phys, 106 Cent St, Wellesley, MA 02481 USA. NR 38 TC 26 Z9 26 U1 1 U2 6 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2000 VL 531 IS 1 BP 321 EP 328 DI 10.1086/308464 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297WM UT WOS:000086105700022 ER PT J AU Henry, GW Baliunas, SL Donahue, RA Fekel, FC Soon, W AF Henry, GW Baliunas, SL Donahue, RA Fekel, FC Soon, W TI Photometric and Ca II H and K spectroscopic variations in nearby sun-like stars with planets. III. SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems; stars : activity; stars : late-type; techniques : photometric; techniques : spectroscopic ID MAIN-SEQUENCE STARS; EXTRASOLAR GIANT PLANETS; SOLAR-TYPE STARS; EFFECTIVE TEMPERATURES; RADIAL-VELOCITY; COOL STARS; CHROMOSPHERIC VARIATIONS; MAGNETIC ACTIVITY; PARENT STARS; TIME-SERIES AB We present the results of an analysis of time-series photometry, Ca II H and K spectrophotometry, and high-dispersion visible spectra of nine nearby Sun-like stars recently identified as having planets. For the six stars whose presumed planets have orbital periods of less than 4 months (tau Boo, 51 Peg, nu And, rho(1) Cnc, rho CrB, and 70 Vir), sine-curve fits to the photometric data show no variations with semiamplitude greater than 1 or 2 parts in 10(4). Photometric variations in 47 UMa are similarly small, although our photometric data of this star are slightly affected by variability of the comparison star. Nonvariability at this level of precision is sufficient to rule out surface magnetic activity as the cause of the observed radial-velocity variations in these seven stars and makes nonradial pulsations unlikely as well. Thus, our photometry provides indirect but strong support for true reflex motions-planets-in these seven stars, but cannot yet so support the planetary hypothesis for the two additional stars, 16 Cyg B and Gl 411. Continued photometric monitoring of the short-period systems may soon result in the direct detection of these planets in reflected light. We have used our photometric fluxes to search for possible transits of the extrasolar planets. Transits definitely do not occur in tau Boo, 51 Peg, nu And, and rho(1) Cnc, and probably do not occur in rho CrB and 70 Vir. Our transit-search results are inconclusive for 47 UMa, and we cannot address the issue for 16 Cyg B and Gl 411. The precision of our photometry is sufficient to detect transits of planets even if they are not gas giants, as currently assumed, but much smaller objects with rocky compositions. The chance of finding at least one transit in the six stars is similar to 40%. We find significant year-to-year photometric variability only in tau Boo, which is not only the youngest star in the sample but also the star with the shallowest convective zone. The interseasonal range in its yearly mean photometric flux is similar to 0.002 mag, roughly twice the 0.0008 mag decadal variation in the Sun's total irradiance. Monitoring of the relative Ca II H and K fluxes began between 1966 and 1968 for 51 Peg, tau Boo, rho CrB, and Gl 411, between 1990 and 1993 for 47 UMa, 70 Vir, 16 Cyg B, and rho(1) Cnc, and in 1996 for nu And. The data have been newly recalibrated for improved long-term instrumental stability, resulting in better precision of the Ca n records. Five of the nine stars in this study have little or no detectable year-to-year variation in Ca II flux. The remaining four show moderate or pronounced variability: tau Boo, whose radial-velocity and photometric variations have comparatively high amplitudes; Gl 411, whose planetary companion was inferred astrometrically, not spectroscopically; rho(1) Cnc, which may undergo decadal cyclic activity; and nu And, which shows moderate year-to-year variability. Except for 47 UMa, intraseasonal variability consistent with rotation was detected in the Ca n records of all stars. However, the rotation periods determined for nu And, 70 Vir, and 16 Cyg B are of low confidence. An examination of the recalibrated Ca n records for 51 Peg finds a rotation period of 22 days, in contrast to our previous result of 37 days. Ages have been estimated from the mean Ca n flux and, where possible, the rotation period. We find general consistency with the ages determined by others comparing properties determined from high-resolution spectroscopy to evolutionary models, although the uncertainties are, in general, large. C1 Tennessee State Univ, Ctr Excellence Informat Syst, Nashville, TN 37203 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Mt Wilson Observ, Pasadena, CA 91106 USA. RP Henry, GW (reprint author), Tennessee State Univ, Ctr Excellence Informat Syst, 330 10th Ave N, Nashville, TN 37203 USA. NR 90 TC 103 Z9 103 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2000 VL 531 IS 1 BP 415 EP 437 DI 10.1086/308466 PN 1 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297WM UT WOS:000086105700033 ER PT J AU Sobczak, GJ McClintock, JE Remillard, RA Cui, W Levine, AM Morgan, EH Orosz, JA Bailyn, CD AF Sobczak, GJ McClintock, JE Remillard, RA Cui, W Levine, AM Morgan, EH Orosz, JA Bailyn, CD TI Correlations between low-frequency quasi-periodic oscillations and spectral parameters in XTE J1550-564 and GRO J1655-40 SO ASTROPHYSICAL JOURNAL LA English DT Article DE black hole physics; stars : individual (XTE J1550-564) stars : individual (GRO J1655-40); X-rays : stars ID BLACK-HOLE CANDIDATES; X-RAY BINARIES; ACCRETION DISKS; MAXIMUM MASS; NEUTRON-STAR; EVOLUTION; SYSTEMS AB Utilizing observations obtained with the Rossi X-Ray Timing Explorer, we examine correlations between the properties of 0.08-22 Hz variable-frequency quasi-periodic oscillations (QPOs) and the X-ray spectral parameters for the black hole candidates XTE J1550-564 and GRO J1655-40. The spectra were fitted to a model including a multitemperature blackbody disk and a power-law component. We find that the QPO frequency and amplitude are well correlated with the spectral parameters, although the correlations found for XTE J1550-564 are generally opposite to those for GRO J1655-40. There is one exception: both sources exhibit a general increase in the QPO frequency as the disk flux increases (or as the rate of mass accretion through the disk increases). In addition, these QPOs are observed only when the power-law component contributes more than 20% of the 2-20 keV flux, which indicates that both the disk and the power-law components are linked to the QPO phenomenon. C1 Harvard Univ, Dept Astron, Cambridge, MA 02138 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Space Res Ctr, Cambridge, MA 02139 USA. Univ Utrecht, Sterrekundig Inst, NL-3508 TA Utrecht, Netherlands. Yale Univ, Dept Astron, New Haven, CT 06520 USA. RP Sobczak, GJ (reprint author), Harvard Univ, Dept Astron, 60 Garden St, Cambridge, MA 02138 USA. OI Cui, Wei/0000-0002-6324-5772 NR 36 TC 89 Z9 90 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2000 VL 531 IS 1 BP 537 EP 545 DI 10.1086/308463 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297WM UT WOS:000086105700042 ER PT J AU Uitenbroek, H AF Uitenbroek, H TI The co fundamental vibration-rotation lines in the solar spectrum. I. Imaging spectroscopy and multidimensional LTE modeling SO ASTROPHYSICAL JOURNAL LA English DT Article DE convection; line : formation; radiative transfer; Sun : atmosphere; Sun : granulation; Sun : infrared ID TRANSFORM SPECTROMETER OBSERVATIONS; TRANSITION REGION; CARBON-MONOXIDE; ENERGY-BALANCE; THERMAL BIFURCATION; TEMPERATURE-MINIMUM; RADIATIVE-TRANSFER; QUIET SUN; K LINES; ATMOSPHERE AB Spectroscopic imaging observations of the CO fundamental vibration-rotation transitions at 4.6 pm, obtained at the Kitt Peak McMath-Pierce facility, show that the dynamics of both the solar granulation and, to a lesser extent, the 5 minute oscillations play an important role in CO line formation. Spectroheliograms made in the cores of strong CO lines display an inverted granular contrast with dark areas corresponding to granule centers and a bright network corresponding to the intergranular lanes. This observation is confirmed by multidimensional radiative transfer modeling of CO line formation in a solar convection-simulation snapshot. Unfortunately, current granulation simulations do not extend to high enough layers in the atmosphere to model formation of CO lines into the chromosphere and close to the solar limb where they exhibit their anomalous temperature behavior. The presented transfer calculations facilitate the interpretation of the observed pattern, predicting that the darkest CO line cores at disk center are associated with the strong adiabatic expansion and cooling that occurs over granule centers when warm upflowing material runs into the steep density gradient of the stable layer above the photosphere. The calculated granulation intensity contrast in the CO line cores is considerably higher than observed, and the calculated spatially averaged line profiles at disk center are deeper than the observed ones. It is speculated that both discrepancies result from the assumption of instantaneous chemical equilibrium which may not be valid in the convective flows. If the CO concentration in the hot convective upflow cannot increase fast enough to adjust to the lower temperatures in the radiatively cooled layer above the photosphere, CO lines would form deeper in the atmosphere, have higher core intensities, and show less contrast, more in agreement with observations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM huitenbroek@cfa.harvard.edu NR 47 TC 43 Z9 43 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 MAR 1 PY 2000 VL 531 IS 1 BP 571 EP 584 DI 10.1086/308454 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297WM UT WOS:000086105700046 ER PT J AU Barmby, P Huchra, JP AF Barmby, P Huchra, JP TI Testing population synthesis models with globular cluster colors SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (M31); galaxies : star clusters; galaxies : stellar content; globular clusters : general ID METALLICITY; SYSTEM; M31; GALAXY AB We have measured an extensive set of UBVRIJHK colors for M31 globular clusters. We compare the predicted simple stellar population colors of three population synthesis models to the intrinsic colors of Galactic and M31 globular clusters. The best-fitting models fit the cluster colors very well: the weighted mean color offsets are all smaller than 0.05 mag. The most significant offsets between model and data are in the U and B passbands; these are not unexpected and are likely caused by problems with the spectral libraries used by the models. The metal-rich clusters ([Fe/H] greater than or similar to -0.8) are best fit by young (8 Gyr) models, while the metal-poor clusters are best fit by older (12-16 Gyr) models. If this range of globular cluster ages is correct, it implies that conditions for cluster formation must have existed for a substantial fraction of the galaxies' lifetimes. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Barmby, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Barmby, Pauline/I-7194-2016 OI Barmby, Pauline/0000-0003-2767-0090 NR 22 TC 27 Z9 27 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2000 VL 531 IS 1 BP L29 EP L32 DI 10.1086/312511 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297WP UT WOS:000086105900008 ER PT J AU Giordano, S Antonucci, E Noci, G Romoli, M Kohl, JL AF Giordano, S Antonucci, E Noci, G Romoli, M Kohl, JL TI Identification of the coronal sources of the fast solar wind SO ASTROPHYSICAL JOURNAL LA English DT Article DE solar wind; Sun : corona; Sun : UV radiation ID VELOCITY DISTRIBUTIONS; ELECTRON-TEMPERATURE; POLAR PLUMES; UVCS/SOHO; HOLE; SOHO AB The present spectroscopic study of the ultraviolet coronal emission in a polar hole, detected on 1996 April 6-9 with the Ultraviolet Coronagraph Spectrometer aboard the Solar and Heliospheric Observatory spacecraft, identifies the interplume lanes and background coronal hole regions as the channels in which the fast solar wind is preferentially accelerated. In interplume lanes, at heliocentric distance 1.7 R., the corona expands at a rate between 105 and 150 km s(-1), that is, much faster than in plumes in which the outflow velocity is between 0 and 65 km s(-1). The wind velocity is inferred from the Doppler dimming of the O VI lambda lambda 1032, 1037 lines, within a range of values, whose lower and upper limit corresponds to anisotropic and isotropic velocity distribution of the oxygen coronal ions, respectively. C1 Osservatorio Astron Torino, I-10025 Pino Torinese, Italy. Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Giordano, S (reprint author), Osservatorio Astron Torino, Strada Osservatorio 20, I-10025 Pino Torinese, Italy. RI Romoli, Marco/H-6859-2012 NR 27 TC 71 Z9 71 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2000 VL 531 IS 1 BP L79 EP L82 DI 10.1086/312525 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297WP UT WOS:000086105900020 ER PT J AU Kraft, RP Forman, W Jones, C Kenter, AT Murray, SS Aldcroft, TL Elvis, MS Evans, IN Fabbiano, G Isobe, T Jerius, D Karovska, M Kim, DW Prestwich, AH Primini, FA Schwartz, DA Schreier, EJ Vikhlinin, AA AF Kraft, RP Forman, W Jones, C Kenter, AT Murray, SS Aldcroft, TL Elvis, MS Evans, IN Fabbiano, G Isobe, T Jerius, D Karovska, M Kim, DW Prestwich, AH Primini, FA Schwartz, DA Schreier, EJ Vikhlinin, AA TI A Chandra high-resolution X-ray image of Centaurus A SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (Centaurus A, NGC 5128); galaxies : jets; X-rays : galaxies ID GLOBULAR-CLUSTERS; CAMERA HRC; AXAF; PERFORMANCE; CALIBRATION; NGC-5128; DISCOVERY; EMISSION; ROSAT; JET AB We present first results from a Chandra X-Ray Observatory observation of the radio galaxy Centaurus A with the High-Resolution Camera. All previously reported major sources of X-ray emission including the bright nucleus, the jet, individual point sources, and diffuse emission are resolved or detected. The spatial resolution of this observation is better than 1 " in the center of the field of view and allows us to resolve X-ray features of this galaxy not previously seen. In particular, we resolve individual knots of emission in the inner jet and diffuse emission between the knots. All of the knots are diffuse at the 1 " level, and several exhibit complex spatial structure. We find the nucleus to be extended by a few tenths of an arcsecond. Our image also suggests the presence of an X-ray counterjet. Weak X-ray emission from the southwest radio lobe is also seen, and we detect 63 pointlike galactic sources (probably X-ray binaries and supernova remnants) above a luminosity limit of similar to 1.7 x 10(37) ergs s(-1). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Space Res Inst, Moscow 117810, Russia. RP Kraft, RP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 30 TC 68 Z9 68 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 1 PY 2000 VL 531 IS 1 BP L9 EP L12 DI 10.1086/312519 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297WP UT WOS:000086105900003 ER PT J AU Hogg, DW Pahre, MA Adelberger, KL Blandford, R Cohen, JG Gautier, TN Jarrett, T Neugebauer, G Steidel, CC AF Hogg, DW Pahre, MA Adelberger, KL Blandford, R Cohen, JG Gautier, TN Jarrett, T Neugebauer, G Steidel, CC TI Caltech Faint Galaxy Redshift Survey. IX. Source detection and photometry in the Hubble Deep Field region SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE cosmology : observations; galaxies : evolution; galaxies : fundamental parameters galaxies : photometry ID NUMBER COUNTS; COLORS AB Detection and photometry of sources in the U(n), G, R, and K(s) bands in a 9 x 9 arcmin(2) region of the sky, centered on the Hubble Deep Field, are described. The data permit construction of complete photometric catalogs to roughly U(n) = 25, G = 26, R = 25.5, K(s) = 20 mag and significant photometric measurements somewhat fainter. The galaxy number density is 1.3 x 10(5) deg(-2) to R = 25.0 mag. Galaxy number counts have slopes d log N/dm = 0.42, 0.33, 0.27, and 0.31 in the U(n), G, R, and K(s) bands, consistent with previous studies and the trend that fainter galaxies are, on average, bluer. Galaxy catalogs selected in the R and K(s) bands are presented, containing 3607 and 488 sources in held areas of 74.8 and 59.4 arcmin(2), to R = 25.5 and K(s) = 20 mag. C1 CALTECH, Palomar Observ, Pasadena, CA 91125 USA. Inst Adv Study, Princeton, NJ 08540 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02139 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. RP Hogg, DW (reprint author), CALTECH, Palomar Observ, Mail Code 130-33, Pasadena, CA 91125 USA. EM hogg@ias.edu; mpahre@cfa.harvard.edu OI Hogg, David/0000-0003-2866-9403 NR 29 TC 33 Z9 33 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD MAR PY 2000 VL 127 IS 1 BP 1 EP 9 DI 10.1086/313318 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 318CE UT WOS:000087265700001 ER PT J AU Erwin, TL AF Erwin, TL TI Arboreal beetles of neotropical forests: Agra Fabricius, a taxonomic supplement for the platyscelis group with new species and distribution records (Coleoptera : Carabidae, Lebiini, Agrina) SO COLEOPTERISTS BULLETIN LA English DT Article AB The platyscelis group of the carabid genus Agra Fabricius. an equatorially centered lineage, consists of 30 species that have a composite range extending from the isthmus of Panama to French Guiana south into Brazil and Bolivia. The majority of species are found in the Amazon Basin. Structural features of both body and appendages are convergent with other carabid beetles that are known to dwell in ant nests, however, no life history of any Agra species is known. The following 12 specific: taxa of the platyscelis group are described as new (type locality in parenthesis): A. tingo new species, (PERU, Huanuco, 13 km S Tingo Maria, Tambillo, Chico Canyon, 09 degrees 15'S, 76 degrees 23'W): A. biolat new species, (PERU, Madre de Dies, 30 air km SW Puerto Maldonado, Rio Tambopata Res., 12 degrees 50'S, 69 degrees 20'W); A. aeris new species, (PERU, Madre de Dies, BIOLAT Biodiversity Station, Pakitza, 11 degrees 56'S, 71 degrees 17'W); A. solimoes new species, (BRAZIL, Amazonas, Ten (Ega), 3 degrees 22'S, 64 degrees 42'W); A. servatorum new species, (PERU, Loreto, 1km SW Boca del Rio Samiria, Vigilante Post No. 1, 04 degrees 30'S, 74 degrees 18'W: A. conhormigas new species, (PERU, Madre de Dies, 30 air km SW Puerto Maldonado, Rio Tambopata Res.. 12 degrees 50'S, 69 degrees 20'W); A. lilu new species, (BRAZIL, Amazonas, Humaita, 07 degrees 32'S 63 degrees 02'W); A. lindae new species, (PERU, Madre de Dies, 30 air km SW Puerto Maldonado, Rio Tambopata Res., 12 degrees 50'S. 69 degrees 20'W); A. rondonia new species, (BRAZIL, Rondonia, Ariquemes, 9 degrees 56'S, 63 degrees 03'W); A. ner new species, (BRAZIL. Amazonas. 2km N Itacoatiara-Manaus Highway, 11 hn, W of Itacoatiara, Canadian Fathers' Pool, 03 degrees 08'S, 58 degrees 28'W); A. manu new species, (PERU, Madre de Dies, Manu Biosphere Res., Pakitza, 11 degrees 56'S, 71 degrees 17'W): A. dnr new species, (PANAMA, Canal Zone, Barro Colorado Is., 09 degrees 10'N, 79 degrees 50'W). The females of A. iquitosana Erwin and A. sasquatch Erwin, and the male of A. varzeicola Erwin are described and illustrated for the first time. A revised key and checklist are provided and distributions of all 33 species are dot-mapped. A general discussion for each of the new species, as well as for 12 additional species for which new locality records were found (A. klugii Brulle, A. limulus Erwin. A. varzeicola. A. iquitosana. A. tarapotana Erwin. A. titan Erwin. A. platyscelis (Chaudoir), A. caliga Erwin, A. feti Erwin, A. semiviridis (Straneo), A. sasquatch Erwin, and A. azureipennis Erwin) is included. Remarks on systematics and biogeography based on the newly described specimens are provided. C1 Smithsonian Inst, Natl Museum Nat Hist, Trop Forest Canopy Lab, Megadivers Grp, Washington, DC 20560 USA. RP Erwin, TL (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Trop Forest Canopy Lab, Megadivers Grp, Washington, DC 20560 USA. NR 29 TC 5 Z9 5 U1 0 U2 2 PU COLEOPTERISTS SOC PI NATCHEZ PA P.O. BOX 767, NATCHEZ, MS 39121 USA SN 0010-065X J9 COLEOPTS BULL JI Coleopt. Bull. PD MAR PY 2000 VL 54 IS 1 BP 90 EP 119 DI 10.1649/0010-065X(2000)054[0090:ABONFA]2.0.CO;2 PG 30 WC Entomology SC Entomology GA 295RF UT WOS:000085981100010 ER PT J AU Jamieson, MJ AF Jamieson, MJ TI Newton-Raphson/log-derivative method for finding eigenenergies SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article ID ALGORITHM AB The Newton-Raphson method for accelerating convergence is combined with the log-derivative propagator to yield an efficient method for finding eigenenergies; some numerical examples are given. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Glasgow, Dept Comp Sci, Glasgow G12 8QQ, Lanark, Scotland. RP Jamieson, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 7 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD MAR PY 2000 VL 125 IS 1-3 BP 193 EP 195 DI 10.1016/S0010-4655(99)00486-5 PG 3 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 285RA UT WOS:000085401000014 ER PT J AU Pukazhenthi, B Noiles, E Pelican, K Donoghue, A Wildt, D Howard, J AF Pukazhenthi, B Noiles, E Pelican, K Donoghue, A Wildt, D Howard, J TI Osmotic effects on feline spermatozoa from normospermic versus teratospermic donors SO CRYOBIOLOGY LA English DT Article DE feline; sperm; osmolality; membrane integrity ID WATER PERMEABILITY COEFFICIENT; ACTIVATION-ENERGY; DOMESTIC CATS; HYDRAULIC CONDUCTIVITY; FROZEN SPERMATOZOA; SWIM-UP; SPERM; CAPACITATION; FERTILIZATION; MORPHOLOGY AB Effects of osmolality stresses on the sperm of normospermic (>60% normal sperm/ejaculate) versus teratospermic (<40% normal sperm) domestic cats and the normospermic leopard cat and the teratospermic clouded leopard were studied. Spermatozoa were exposed to various anisotonic solutions in a single step or returned to near isotonic conditions in a single step after exposure to anisotonic solutions. The percentage of sperm motility was measured subjectively, and dual fluorescent stains were used to assess membrane integrity by flow cytometry. The percentage of sperm motility declined (P < 0.05) in domestic cat sperm exposed to osmolalities <200 and >450 mOsm. Spermatozoa from ail felines underwent marked (P < 0.05) membrane disruption following a hypotonic stress, but sperm from teratospermic donors experienced greater (P < 0.05) membrane disruption in response to decreased osmolality. While feline spermatozoa appeared to be highly resistant to hypertonic (600, 1200, and 2400 mOsm) conditions, with >85% of the cells maintaining intact membranes, severe membrane disruption occurred when cells were returned to isotonicity in a single step. There was no difference (P > 0.05) between a 1- and 5-min exposure to various anisotonic solutions. Similarly, sperm from normospermic and teratospermic domestic cats responded identically after exposure to ionic or nonionic solute. Results demonstrate that: (1) spermatozoa from teratospermic males are more vulnerable to a hypotonic stress than sperm from normospermic counterparts; (2) in response to small deviations in osmolality, feline sperm experience a more rapid decline in motility than membrane integrity; and (3) an abrupt return to isotonicity after a hypertonic stress causes extensive sperm membrane damage regardless of ejaculate quality. (C) 2000 Academic Press. C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. ARS, Germplasm & Gamete Physiol Lab, USDA, Beltsville, MD 20705 USA. RP Pukazhenthi, B (reprint author), Smithsonian Inst, Natl Zool Pk, Reprod Physiol Program, 3001 Connecticut Ave NW, Washington, DC 20008 USA. FU NCRR NIH HHS [K01RR00135] NR 39 TC 49 Z9 50 U1 0 U2 5 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0011-2240 J9 CRYOBIOLOGY JI Cryobiology PD MAR PY 2000 VL 40 IS 2 BP 139 EP 150 DI 10.1006/cryo.2000.2233 PG 12 WC Biology; Physiology SC Life Sciences & Biomedicine - Other Topics; Physiology GA 313ZA UT WOS:000087028600006 PM 10788313 ER PT J AU Kiers, ET Lovelock, CE Krueger, EL Herre, EA AF Kiers, ET Lovelock, CE Krueger, EL Herre, EA TI Differential effects of tropical arbuscular mycorrhizal fungal inocula on root colonization and tree seedling growth: implications for tropical forest diversity SO ECOLOGY LETTERS LA English DT Article DE Anacardium; Dipteryx; diversity; Ficus; Licania; Luehea; mutualism; mycorrhizae; Ochroma; reciprocal inoculation; specificity; Theobroma; tropical forests ID PLANT COMMUNITY STRUCTURE; DISPERSAL; DYNAMICS AB The potential for mycorrhizae to influence the diversity and structuring of plant communities depends on whether their affinities and effects differ across a suite of potential host species. In order to assess this potential for a tropical forest community in Panama, we conducted three reciprocal inoculation experiments using seedlings from six native tree species. Seeds were germinated in sterile soil and then exposed to arbuscular mycorrhizal fungi in current association with naturally infected roots from adults of either the same or different species growing in intact forest. The tree species represent a range of life histories, including early successional pioneers, a persistent understory species, and emergent species, typical of mature forest. Collectively, these experiments show: (i) the seedlings of small-seeded pioneer species were more dependent on mycorrhizal inocula for initial survival and growth; (ii) although mycorrhizal fungi from all inocula were able to colonize the roots of all host species, the inoculum potential (the infectivity of an inoculum of a given concentration) and root colonization varied depending on the identity of the host seedling and the source of the inoculum; and (iii) different mycorrhizal fungal inocula also produced differences in growth depending on the host species. These differences indicate that host-mycorrhizal fungal interactions in tropical forests are characterized by greater complexity than has previously been demonstrated, and suggest that tropical mycorrhizal fungal communities have the potential to differentially influence seedling recruitment among host species and thereby affect community composition. C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Herre, EA (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. RI Lovelock, Catherine/G-7370-2012 OI Lovelock, Catherine/0000-0002-2219-6855 NR 39 TC 88 Z9 97 U1 3 U2 52 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 1461-023X J9 ECOL LETT JI Ecol. Lett. PD MAR PY 2000 VL 3 IS 2 BP 106 EP 113 DI 10.1046/j.1461-0248.2000.00126.x PG 8 WC Ecology SC Environmental Sciences & Ecology GA 296JK UT WOS:000086021100008 ER PT J AU Gibson, TG Bybell, LM Thomas, E Zachos, JC AF Gibson, TG Bybell, LM Thomas, E Zachos, JC TI Kaolinite distribution in Paleocene/Eocene boundary strata of northeastern United States and Pakistan - climatic and stratigraphic implications SO GFF LA English DT Article C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, MRC 121, Washington, DC 20560 USA. US Geol Survey, Reston, VA 20192 USA. Wesleyan Univ, Dept Earth & Environm Sci, Middletown, CT 06457 USA. Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. RP Gibson, TG (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, MRC 121, Washington, DC 20560 USA. RI Zachos, James/A-7674-2008; Thomas, Ellen/E-5573-2011 OI Thomas, Ellen/0000-0002-7141-9904 NR 3 TC 2 Z9 2 U1 0 U2 0 PU SWEDISH SCIENCE PRESS PI UPPSALA PA BOX 118, S751 04 UPPSALA, SWEDEN SN 1103-5897 J9 GFF JI GFF PD MAR PY 2000 VL 122 BP 56 EP 56 PN 1 PG 1 WC Geology; Paleontology SC Geology; Paleontology GA 293LN UT WOS:000085853400027 ER PT J AU Wilf, P Labandeira, CC AF Wilf, P Labandeira, CC TI Effects of Paleocene-Eocene warming on insect herbivory SO GFF LA English DT Article ID LEAF C1 Smithsonian Inst, Museum Natl Hist Nat, Dept Paleobiol, Washington, DC 20560 USA. RP Wilf, P (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Paleobiol, Washington, DC 20560 USA. NR 16 TC 1 Z9 1 U1 0 U2 3 PU SWEDISH SCIENCE PRESS PI UPPSALA PA BOX 118, S751 04 UPPSALA, SWEDEN SN 1103-5897 J9 GFF JI GFF PD MAR PY 2000 VL 122 BP 178 EP 179 PN 1 PG 2 WC Geology; Paleontology SC Geology; Paleontology GA 293LN UT WOS:000085853400087 ER PT J AU Wing, SL AF Wing, SL TI Cool, warm, cool, warm - climate oscillation and floral change during the Paleocene/Eocene boundary interval SO GFF LA English DT Article ID BIGHORN BASIN; THERMAL MAXIMUM C1 Smithsonian Inst, Dept Paleobiol, MRC 121, Washington, DC 20560 USA. RP Wing, SL (reprint author), Smithsonian Inst, Dept Paleobiol, MRC 121, 10th & Constitut Ave NW, Washington, DC 20560 USA. OI Wing, Scott/0000-0002-2954-8905 NR 7 TC 5 Z9 5 U1 1 U2 3 PU SWEDISH SCIENCE PRESS PI UPPSALA PA BOX 118, S751 04 UPPSALA, SWEDEN SN 1103-5897 J9 GFF JI GFF PD MAR PY 2000 VL 122 BP 182 EP 183 PN 1 PG 2 WC Geology; Paleontology SC Geology; Paleontology GA 293LN UT WOS:000085853400089 ER PT J AU Wilgenbusch, JC Gantz, DT AF Wilgenbusch, JC Gantz, DT TI The effects of hormonally induced oviposition on egg viability in the common snapping turtle Chelydra serpentina SO HERPETOLOGICA LA English DT Article DE oxytocin; eggs; egg collection; turtles; hormonal induction; Chelydra serpentina ID WATER RELATIONS; MIXED MODELS; TEMPERATURE; EMBRYOS AB We collected eggs of the common snapping turtle (Chelydra serpentina) over two consecutive years both from gravid females hormonally induced to oviposit and from newly (<12 h) constructed nests. Eggs were incubated in the laboratory under wet and dry conditions to determine whether the method of procurement influenced egg viability. Net gain in egg mass during incubation and hatching success (egg survivorship) were used as measures of egg viability. Hatchling body size was also analyzed for effects due to egg procurement method. Eggs collected from nests gained significantly more mass during the incubation period than did eggs collected from females hormonally induced to oviposit. This difference may have resulted from the particular way that eggs were collected. Females were induced to oviposit directly into water and, therefore, their eggs may have had higher water potential at the start of incubation than eggs collected from nests. Our analyses were unable to detect differences in hatching success and hatchling; body size between the egg procurement methods. C1 George Mason Univ, Dept Biol, Fairfax, VA 22030 USA. George Mason Univ, Ctr Computat Stat, Fairfax, VA 22030 USA. RP Wilgenbusch, JC (reprint author), Smithsonian Museum, Lab Mol Systemat, Support Ctr, 4210 Silver Hill Rd, Suitland, MD 20746 USA. NR 25 TC 3 Z9 3 U1 0 U2 2 PU HERPETOLOGISTS LEAGUE PI JOHNSON CITY PA EAST TENNESSEE STATE UNIV, DEPT BIOLOGICAL SCIENCES, BOX 70726, JOHNSON CITY, TN 37614-0726 USA SN 0018-0831 J9 HERPETOLOGICA JI Herpetologica PD MAR PY 2000 VL 56 IS 1 BP 1 EP 7 PG 7 WC Zoology SC Zoology GA 290DN UT WOS:000085661100001 ER PT J AU Wright, HE AF Wright, HE TI Developing a photographic collection - National Museum of American History SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. RP Wright, HE (reprint author), Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 1 EP 6 PG 6 WC Art SC Art GA 286LZ UT WOS:000085448600002 ER PT J AU Warner, DJ AF Warner, DJ TI The Draper Family material - National Museum of American History (Photography) SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. RP Warner, DJ (reprint author), Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 52 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 16 EP 23 PG 8 WC Art SC Art GA 286LZ UT WOS:000085448600004 ER PT J AU Delaney, MA AF Delaney, MA TI Collecting pictorialism at the Smithsonian 1896-1969 (Photography) SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. RP Delaney, MA (reprint author), Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 12 TC 0 Z9 0 U1 1 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 31 EP 36 PG 6 WC Art SC Art GA 286LZ UT WOS:000085448600006 ER PT J AU Perich, ST AF Perich, ST TI Process and 3-D materials - National Museum of American History SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. RP Perich, ST (reprint author), Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 37 EP 41 PG 5 WC Art SC Art GA 286LZ UT WOS:000085448600007 ER PT J AU Wright, HE AF Wright, HE TI The Osborne Collection - Photomechanical incunabula SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. RP Wright, HE (reprint author), Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 22 TC 1 Z9 1 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 42 EP 46 PG 5 WC Art SC Art GA 286LZ UT WOS:000085448600008 ER PT J AU Haberstich, D AF Haberstich, D TI The Archives Center and photography - National Museum of American History SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. RP Haberstich, D (reprint author), Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 47 EP 51 PG 5 WC Art SC Art GA 286LZ UT WOS:000085448600009 ER PT J AU Liebhold, P AF Liebhold, P TI Hillotypes - A sad tale of invention SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Washington, DC 20560 USA. RP Liebhold, P (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 52 EP 52 PG 1 WC Art SC Art GA 286LZ UT WOS:000085448600010 ER PT J AU Fleming, PR AF Fleming, PR TI An 'accumulation' of Native American portraits (Smithsonian Institution, US, Indians) SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Washington, DC 20560 USA. RP Fleming, PR (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 57 EP 58 PG 2 WC Art SC Art GA 286LZ UT WOS:000085448600013 ER PT J AU Green, R AF Green, R TI Gertrude Kasebier's 'Indian' photographs (Smithsonian Institution, anthropology) SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. RP Green, R (reprint author), Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 3 TC 0 Z9 0 U1 1 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 58 EP 60 PG 3 WC Art SC Art GA 286LZ UT WOS:000085448600014 ER PT J AU Delaney, MA Perich, ST AF Delaney, MA Perich, ST TI Local photographers in the National Collection (US) SO HISTORY OF PHOTOGRAPHY LA English DT Article C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. RP Delaney, MA (reprint author), Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP 63 EP 64 PG 2 WC Art SC Art GA 286LZ UT WOS:000085448600016 ER PT J AU Wright, HE AF Wright, HE TI The Photographic History Collection, National Museum of American History, Smithsonian Institution - Guest editorial SO HISTORY OF PHOTOGRAPHY LA English DT Editorial Material C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. RP Wright, HE (reprint author), Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0308-7298 J9 HIST PHOTOGR JI Hist. Photogr. PD SPR PY 2000 VL 24 IS 1 BP U1 EP U1 PG 1 WC Art SC Art GA 286LZ UT WOS:000085448600001 ER PT J AU Piperno, DR Andres, TC Stothert, KE AF Piperno, DR Andres, TC Stothert, KE TI Phytoliths in Cucurbita and other neotropical curcurbitaceae and their occurrence in early archaeological sties fromt he Lowland American tropics SO JOURNAL OF ARCHAEOLOGICAL SCIENCE LA English DT Article DE squashes and gourds; phytoliths; domestication; lowland neotropics ID ADAPTATIONS AB Cucurbita spp. (squashes and gourds), together with bottle gourd (Lagenaria siceraria), were among the earliest plants manipulated and domesticated in the Americas. Although at least one squash species, Cucurbita moschata, was domesticated in the lowland Neotropics, little is known about its history because preservation of plant remains in sites from the tropical forest is poor. Phytolith analysis has the potential to help in our understanding of early cultural uses of Cucurbita and other important Cucurbitaceae in the American tropical forest. Phytoliths from the fruits of three modern domesticated Cucurbita species were compared with seven wild species of Cucurbita and 41 species of cucurbits from 22 other genera in the Cucurbitaceae. Cucurbita and Lagenaria phytoliths are distinctive and they have been recovered from archaeological deposits in the lowland Neotropics dating to the terminal Pleistocene and early Holocene periods. Phytolith evidence indicates that a domesticated Cucurbita was present on the northern South American landscape by at least 7000 BP, and quite possibly by 9000 BP. C1 Smithsonian Trop Res Inst, Balboa, Panama. Cornell Univ, Ithaca, NY 14853 USA. Univ Texas, Ctr Archaeol Res, San Antonio, TX USA. RP Piperno, DR (reprint author), Smithsonian Trop Res Inst, Balboa, Panama. NR 28 TC 51 Z9 57 U1 1 U2 11 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0305-4403 J9 J ARCHAEOL SCI JI J. Archaeol. Sci. PD MAR PY 2000 VL 27 IS 3 BP 193 EP 208 DI 10.1006/jasc.1999.0443 PG 16 WC Anthropology; Archaeology; Geosciences, Multidisciplinary SC Anthropology; Archaeology; Geology GA 297YV UT WOS:000086111600002 ER PT J AU Stanley, DJ Hait, AK Jorstad, TF AF Stanley, DJ Hait, AK Jorstad, TF TI Iron-stained quartz to distinguish holocene deltaic from pleistocene alluvial deposits in small core samples SO JOURNAL OF COASTAL RESEARCH LA English DT Article DE climate; Ganges-Brahmaputra delta; delta stratigraphy; eolian transport; fluvial processes; Holocene; iron-oxide coatings; laterisation; Nile delta; Pleistocene; sea-level change; sediment cores; transport processes; weathering ID NILE DELTA; SEA-LEVEL; DESERT SANDS; ORIGIN; AUSTRALIA; EGYPT AB The recorded Proportions of three Sand-size quartz grain types-clear, partially stained and fully stained-are used to distinguish Holocene from Pleistocene sediment in small core cuttings and washings of borings recovered in the Nile and Ganges-Brahmaputra deltas. To verify the general applicability of the method, we selected for study 343 samples from 13 cores in these two deltas that formed in markedly different geographic and climatic settings: the Nile delta in the highly arid and warm to hot region of Egypt; and, in contrast, the Ganges-Brahmaputra delta in the humid hot region of India and Bangladesh. Analyses indicate that pigments are composed of iron oxides, likely including goethite. Samples of late Pleistocene alluvial sediment show consistently higher proportions of both partially and fully coated quartz types than in the overlying Holocene deltaic deposits. This finding prevails regardless of factors such as sediment process, transport distance, lithology of sediment section examined, and sand grain texture. On the basis of actual measurements made in the present investigation, it appears possible to recognize Holocene and Pleistocene strata by counting the 3 sand-sized quartz grain types (325-350 grains/sample) in as few as 10 to 20 small samples that are distributed downcore in a minimum of 3 to 6 borings. The method is simple, rapid, inexpensive, and particularly well suited for stratigraphic interpretation of sediment sections that are incomplete and/or poorly dated. C1 Smithsonian Inst, Deltas Global Change Program, Paleobiol NMNH E206, Washington, DC 20560 USA. Ctr Study Man & Environm, Calcutta, W Bengal, India. RP Stanley, DJ (reprint author), Smithsonian Inst, Deltas Global Change Program, Paleobiol NMNH E206, Washington, DC 20560 USA. NR 30 TC 7 Z9 7 U1 0 U2 0 PU COASTAL EDUCATION & RESEARCH FOUNDATION PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 USA SN 0749-0208 J9 J COASTAL RES JI J. Coast. Res. PD SPR PY 2000 VL 16 IS 2 BP 357 EP 367 PG 11 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA 319DY UT WOS:000087327300012 ER PT J AU Chen, ZY Stanley, DJ Wright, EE AF Chen, ZY Stanley, DJ Wright, EE TI Selective sorting, storage and progressive dilution of sediment in two tropical deltas, Veracruz, Mexico SO JOURNAL OF COASTAL RESEARCH LA English DT Article DE archaeological sites; delta sedimentation; fluvial discharge; Gulf of Mexico; Holocene; particle composition; rain pattern; sediment load; texture; transport processes AB Compositional and textural attributes of the surficial sediment in deltaic settings typically differ from the sediment load carried by their source rivers. This phenomenon is evaluated here by semiquantitative study of the variability of petrologic characteristics in different delta subenvironments of the Nautla and Tecolutla deltas along Mexico's Veracruz coast. Sediment composition and texture in the different environments of both deltas are related to processes that involve selective sorting during seasonal flooding and temporary storage after deposition. Displacement of particles of different size, density and shape onto the two tropical delta plains is controlled by fluctuating fluvial discharge that responds to a highly variable seasonal rainfall pattern. These discharge variations induce changes in hydraulic equivalence and, consequently, the release of substantially different proportions of volcanic, mica, heavy mineral and grain-size fractions in the Veracruz delta settings. These phenomena, together with progressive dilution of sediment upon reaching the coast, result in significant modifications to the original petrologic attributes of fluvial loads as they are transported seaward. Comparable variations of composition and texture in subsurface Holocene sections would likely record former large-scale climate, rainfall and fluvial discharge fluctuations. Petrologic analysis of core sections recovered at Prehispanic sites on the two deltas could be used to detect past long-term flooding pulses and droughts, natural events that archaeologists suggest caused deterioration of subsistence resources, stratigraphic hiatuses, cultural discontinuities and human migrations in this region. C1 E China Normal Univ, State Key Lab Estuarine & Coastal Res, Shanghai 200062, Peoples R China. Smithsonian Inst, Deltas Global Change Program, NMNH Paleobiol E206, Washington, DC 20560 USA. Coastal Carolina Univ, Dept Marine Sci, Conway, SC 29528 USA. RP Chen, ZY (reprint author), E China Normal Univ, State Key Lab Estuarine & Coastal Res, Shanghai 200062, Peoples R China. NR 25 TC 5 Z9 6 U1 0 U2 3 PU COASTAL EDUCATION & RESEARCH FOUNDATION PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 USA SN 0749-0208 J9 J COASTAL RES JI J. Coast. Res. PD SPR PY 2000 VL 16 IS 2 BP 470 EP 481 PG 12 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA 319DY UT WOS:000087327300023 ER PT J AU Ubelaker, DH AF Ubelaker, DH TI Symposium: Essays honoring T. Dale Stewart, MD(1901-1997) SO JOURNAL OF FORENSIC SCIENCES LA English DT Editorial Material C1 Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Ubelaker, DH (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD MAR PY 2000 VL 45 IS 2 BP 243 EP 243 PG 1 WC Medicine, Legal SC Legal Medicine GA 298RP UT WOS:000086153200001 ER PT J AU Ubelaker, DH AF Ubelaker, DH TI The forensic anthropology legacy of T. Dale Stewart (1901-1997) SO JOURNAL OF FORENSIC SCIENCES LA English DT Biographical-Item DE forensic science; T-Dale Stewart; history; forensic anthropology AB T. Dale Stewart (1901-1997) began his Smithsonian career as a temporary aide to Ales Hrdlicka (1869-1943) in 1924. At the time of his death in 1997, he was regarded world-wide as an authority who led the professional development of American forensic anthropology. He was a prodigious researcher, best known for his meticulous attention to detail, balanced scientific judgment, keen sense of research design, and ability for synthesis. Stewart's publications, extensive casework for the FBI and others, his court testimony, publications, professional contacts, and organizational activity merit him a prominent place in the history of American forensic anthropology. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, Washington, DC 20560 USA. RP Ubelaker, DH (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, MRC 112, Washington, DC 20560 USA. NR 1 TC 4 Z9 5 U1 0 U2 1 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD MAR PY 2000 VL 45 IS 2 BP 245 EP + PG 20 WC Medicine, Legal SC Legal Medicine GA 298RP UT WOS:000086153200002 PM 10782942 ER PT J AU Ubelaker, DH AF Ubelaker, DH TI T. Dale Stewart's perspective on his career as a forensic anthropologist at the Smithsonian SO JOURNAL OF FORENSIC SCIENCES LA English DT Biographical-Item DE forensic science; T. D. Stewart; history; oral history interview C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, Washington, DC 20560 USA. RP Ubelaker, DH (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, MRC 112, Washington, DC 20560 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD MAR PY 2000 VL 45 IS 2 BP 269 EP 278 PG 10 WC Medicine, Legal SC Legal Medicine GA 298RP UT WOS:000086153200007 PM 10782947 ER PT J AU Hu, YQ Esser, R Habbal, SR AF Hu, YQ Esser, R Habbal, SR TI A four-fluid turbulence-driven solar wind model for preferential acceleration and heating of heavy ions SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY ALFVENIC FLUCTUATIONS; CYCLOTRON-RESONANCE; RADIAL EVOLUTION; POWER SPECTRUM; CORONAL HOLES; INNER CORONA; TEMPERATURE; ANISOTROPY; DISPERSION; VELOCITY AB We present for the first time a one-dimensional, four-fluid turbulence-driven solar wind model in order to investigate the preferential acceleration and heating of heavy ions by the resonant cyclotron interaction with parallel-propagating left-hand-polarized ion cyclotron waves. The model contains four species: electrons, protons, alpha particles, and one species of minor ions. A Kolmogorov type of cascade effect is introduced to transfer energy from the low-frequency Alfven waves to the high-frequency ion cyclotron waves, which are assumed to be entirely dissipated by the wave-particle interaction. The quasi-linear theory of the wave-particle interaction is invoked to distribute the dissipated wave energy among the three ion species based on a given power law spectrum of the ion cyclotron waves and the cold plasma dispersion relation. It is found that in terms of the cold plasma dispersion relation, the dispersion generated by all ion species has an appreciable influence on both the behavior of the major species and the preferential acceleration and heating of the minor ions. The larger the number of species included in the dispersion relation is, the stronger preferential acceleration and heating produced by the waves for the heavy ions close to the Sun will be. A detailed comparison is carried out between two cases, one with and the other without the dispersive effect of the minor ions. Although the solutions for the two cases are somewhat different, they predict a more or less similar behavior of the minor ions, which essentially agrees with recent observations from SOHO. This indicates that the resonant cyclotron interaction may be responsible for the preferential acceleration and heating of minor ions in the fast solar wind. Furthermore, the influence of minor ions on the proton-alpha solar wind is found to be dominated by the dispersive effect of the minor ions. Even though such an influence is exaggerated by the cold plasma dispersion relation, it is still small and remains within the present observational uncertainties. Therefore minor ions may be treated approximately as test particles in the solar wind. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Sci & Technol China, Dept Earth & Space Sci, Hefei 230026, Peoples R China. RP Hu, YQ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 51 TC 56 Z9 59 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 2000 VL 105 IS A3 BP 5093 EP 5111 DI 10.1029/1999JA900430 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 288TY UT WOS:000085581600002 ER PT J AU Heyer, WR AF Heyer, WR TI The lectotype of Cystignathus hylodes Reinhardt and Lutken, 1862 SO JOURNAL OF HERPETOLOGY LA English DT Article C1 Natl Museum Nat Hist, Dept Vertebrate Zool, Smithsonian Inst, Washington, DC 20560 USA. RP Heyer, WR (reprint author), Natl Museum Nat Hist, Dept Vertebrate Zool, Smithsonian Inst, Washington, DC 20560 USA. NR 9 TC 1 Z9 3 U1 0 U2 0 PU SOC STUDY AMPHIBIANS REPTILES PI ST LOUIS PA C/O ROBERT D ALDRIDGE, ST LOUIS UNIV, DEPT BIOLOGY, 3507 LACLEDE, ST LOUIS, MO 63103 USA SN 0022-1511 J9 J HERPETOL JI J. Herpetol. PD MAR PY 2000 VL 34 IS 1 BP 150 EP 153 DI 10.2307/1565254 PG 4 WC Zoology SC Zoology GA 294GV UT WOS:000085904300024 ER PT J AU Mercader, J Brooks, A Piperno, D Marti, R Holst, I AF Mercader, J Brooks, A Piperno, D Marti, R Holst, I TI Ancient foragers as early colonizers of tropical forests SO JOURNAL OF HUMAN EVOLUTION LA English DT Meeting Abstract C1 Smithsonian Trop Res Inst, Panama City, Panama. George Washington Univ, Dept Anthropol, Washington, DC 20052 USA. Univ Nacl Educ Distancia, Dept Prehist, E-28040 Madrid, Spain. NR 0 TC 1 Z9 1 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0047-2484 J9 J HUM EVOL JI J. Hum. Evol. PD MAR PY 2000 VL 38 IS 3 BP A21 EP A22 PG 2 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 294JZ UT WOS:000085909300039 ER PT J AU Sikes, NE AF Sikes, NE TI Using paleosol stable isotopes to reconstruct Olduvai basin landscapes SO JOURNAL OF HUMAN EVOLUTION LA English DT Meeting Abstract C1 Smithsonian Inst, Smithson Light Isotope Lab, Museum Support Ctr, Washington, DC 20560 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0047-2484 J9 J HUM EVOL JI J. Hum. Evol. PD MAR PY 2000 VL 38 IS 3 BP A28 EP A28 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 294JZ UT WOS:000085909300050 ER PT J AU Ito, M Yahara, T King, RM Watanabe, K Oshita, S Yokoyama, J Crawford, DJ AF Ito, M Yahara, T King, RM Watanabe, K Oshita, S Yokoyama, J Crawford, DJ TI Molecular phylogeny of Eupatorieae (Asteraceae) estimated from cpDNA RFLP and its implication for the polyploid origin hypothesis of the tribe SO JOURNAL OF PLANT RESEARCH LA English DT Article DE ancient polyploidy; Asteraceae; chloroplast DNA; diploidization; dysploidy; Eupatorieae ID HIGH CHROMOSOME-NUMBERS; CHLOROPLAST-DNA; EVOLUTION; ASTEREAE; CLADES AB The tribe Eupatorieae has a chromosome base number that ranges from 4 to 25. A molecular phylogenetic analysis using cpDNA restriction site mutations was performed. Fifteen species representing 13 subtribes of the tribe Eupatorieae were examined, together with three species from the tribe Heliantheae as outgroups. A total of 103 restriction site mutations were detected, and 31 of these were phylogenetically informative. Parsimony analysis produced a single most parsimonious tree with 117 steps. This tree suggested that two clades diverged early in the evolution of the tribe Eupatorieae. One clade includes Neomirandea (x=17 and 25), Ageratina (x=17) and Sclerolepis (x=15) with the higher chromosome base numbers, and the other includes Mikania (x=17) and the remaining genera with lower chromosome base numbers (x=10-11). However, the monophyly of the former clade is supported with a low bootstrap value. In the latter clade, Mikania (x= 17) diverged first, then Stevia (x=11), and finally eight genera with x=10 diverged in succession. This result supports the hypothesis that the genera in the tribe Eupatorieae with x=10 evolved from an ancestor with a higher base number, and the tribe is of polyploid origin. C1 Chiba Univ, Fac Sci, Dept Biol, Chiba 2638522, Japan. Kyushu Univ, Fac Sci, Dept Biol, Fukuoka 8128581, Japan. Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. Kobe Univ, Fac Sci, Dept Biol, Kobe, Hyogo 6578501, Japan. Tohoku Univ, Grad Sch Sci, Dept Biol, Sendai, Miyagi 9808578, Japan. Ohio State Univ, Dept Plant Sci, Columbus, OH 43210 USA. RP Ito, M (reprint author), Chiba Univ, Fac Sci, Dept Biol, Chiba 2638522, Japan. NR 33 TC 13 Z9 14 U1 0 U2 9 PU BOTANICAL SOC JAPAN PI TOKYO PA TOSHIN BUILDING HONGO 2-27-2 BUNKYO-KU, TOKYO, 113, JAPAN SN 0918-9440 J9 J PLANT RES JI J. Plant Res. PD MAR PY 2000 VL 113 IS 1109 BP 91 EP 96 DI 10.1007/PL00013919 PG 6 WC Plant Sciences SC Plant Sciences GA 308DN UT WOS:000086695400011 ER PT J AU Lorenzini, EC Cosmo, ML Kaiser, M Bangham, ME Vonderwell, DJ Johnson, L AF Lorenzini, EC Cosmo, ML Kaiser, M Bangham, ME Vonderwell, DJ Johnson, L TI Mission analysis of spinning systems for transfers from low orbits to geostationary SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB An analysis of the use of spaceborne spinning tethers for a reusable system to transfer payloads with a mass up to 4000 kg from low orbits to geostationary is presented. Results indicate that a two-stage system is lighter than a single-stage tethered system with present-day tether materials. A first stage in low orbit and a second stage in medium Earth orbit provide the required velocity increments for injecting the payload into geotransfer orbit with the final orbit circularization provided by the satellite kick motor. The orbits of the stages are resonant in order to provide periodic encounters and are optimized with the goal of reducing the overall system mass. The close-approach dynamics between the second stage and the payload released from the first stage is simulated to demonstrate the salient features of the rendezvous process. A total of 10 transfers over two years of operation without refueling is adopted for computing the propellant needed to reboost the stages, A preliminary analysis leads to the conclusion that a two-stage tethered system is more competitive, on a mass basis, than a chemical upper stage after two transfers. C1 Harvard Smithsonian Ctr Astrophys, Radio & Geoastron Div, Cambridge, MA 02138 USA. Tech Univ Munich, Inst Astron, D-8000 Munich, Germany. Boeing Co, Def & Space Grp, Huntsville, AL 35824 USA. NASA, George C Marshall Space Flight Ctr, Program Dev, Huntsville, AL 35812 USA. RP Lorenzini, EC (reprint author), Harvard Smithsonian Ctr Astrophys, Radio & Geoastron Div, MS80,60 Garden St, Cambridge, MA 02138 USA. NR 10 TC 18 Z9 21 U1 0 U2 4 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 MAR-APR PY 2000 VL 37 IS 2 BP 165 EP 172 DI 10.2514/2.3562 PG 8 WC Engineering, Aerospace SC Engineering GA 302XC UT WOS:000086390900003 ER PT J AU Johnson, L Estes, RD Lorenzini, E Martinez-Sanchez, M Sanmartin, J AF Johnson, L Estes, RD Lorenzini, E Martinez-Sanchez, M Sanmartin, J TI Propulsive Small Expendable Deployer System experiment SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB Relatively short electrodynamic tethers can extract orbital energy to "push" against a planetary magnetic field to achieve propulsion without the expenditure of propellant. The Propulsive Small Expendable Deployer System experiment will use the flight-proven Small Expendable Deployer System to deploy a 5-km bare aluminum tether from a Delta II upper stage to achieve approximate to 0.4-N drag thrust, thus lowering the altitude of the stage. The experiment will use a predominantly bare tether for current collection in lien of the endmass collector and insulated tether used on previous missions. The flight experiment is a precursor to a more ambitious electrodynamic tether upper-stage demonstration mission that will be capable of orbit-raising, -lowering, and inclination changes, all using electrodynamic thrust. The expected performance of the tether propulsion system during the experiment is described. C1 NASA, George C Marshall Space Flight Ctr, Adv Space Transportat Program, Huntsville, AL 35812 USA. Harvard Smithsonian Ctr Astrophys, Radio & Geoastron Div, Cambridge, MA 02138 USA. MIT, Cambridge, MA 02139 USA. Univ Politecn Madrid, Escuela Tecn Super Ingn Aeronaut, E-28040 Madrid, Spain. RP Johnson, L (reprint author), NASA, George C Marshall Space Flight Ctr, Adv Space Transportat Program, Mail Code TD15, Huntsville, AL 35812 USA. NR 7 TC 26 Z9 26 U1 0 U2 4 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 MAR-APR PY 2000 VL 37 IS 2 BP 173 EP 176 DI 10.2514/2.3563 PG 4 WC Engineering, Aerospace SC Engineering GA 302XC UT WOS:000086390900004 ER PT J AU Estes, RD Sanmartin, J Martinez-Sanchez, M AF Estes, RD Sanmartin, J Martinez-Sanchez, M TI Performance of bare-tether systems under varying magnetic and plasma conditions SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID TSS-1R MISSION; CURRENTS AB Electrodynamic tethered systems, in which an exposed portion of the conducting tether itself collects electrons from the ionosphere, promise to attain currents of 10 A or more in low Earth orbit. For the first time, another desirable feature of such bare-tether systems is reported and analyzed in detail: Collection by a bare tether is relatively insensitive to variations in electron density that are regularly encountered on each revolution of an orbit. This self-adjusting property of bare-tether systems occurs because the electron-collecting area on the tether is not fixed, but extends along its positively biased portion, and because the current varies as collecting length to a power greater than unity, How this adjustment to density variations follows from the basic collection law of thin cylinders is shown. The effect of variations in the motionally induced tether voltage is also analyzed. Both power and thruster modes are considered. The performance of bare tether systems to tethered systems is compared using passive spherical collectors of fixed area, taking into consideration recent experimental results. Calculations taking into account motional voltage and plasma density around a realistic orbit for bare-tether systems suitable for space station applications are also presented. C1 Harvard Smithsonian Ctr Astrophys, Radio & Geoastron Div, Cambridge, MA 02138 USA. Univ Politecn Madrid, Escuela Tecn Super Ingn Aeronaut, E-28040 Madrid, Spain. MIT, Cambridge, MA 02139 USA. RP Estes, RD (reprint author), Harvard Smithsonian Ctr Astrophys, Radio & Geoastron Div, MS 80,60 Garden St, Cambridge, MA 02138 USA. NR 11 TC 15 Z9 16 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2000 VL 37 IS 2 BP 197 EP 204 DI 10.2514/2.3566 PG 8 WC Engineering, Aerospace SC Engineering GA 302XC UT WOS:000086390900007 ER PT J AU Estes, RD Lorenzini, EC Sanmartin, J Pelaez, J Martinez-Sanchez, M Johnson, CL Vas, IE AF Estes, RD Lorenzini, EC Sanmartin, J Pelaez, J Martinez-Sanchez, M Johnson, CL Vas, IE TI Bare tethers for electrodynamic spacecraft propulsion SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID CURRENT COLLECTION; PRESHEATH; SATELLITE; PROBE; ORBIT AB Electrodynamic tether thrusters can use the power provided by solar panels to drive a current in the tether and then the Lorentz force to push against the Earth's magnetic field, thereby achieving propulsion without the expenditure of onboard energy sources or propellant. Practical tether propulsion depends critically on being able to extract multiamp electron currents from the ionosphere with relatively short tethers (10 km or less) and reasonably low power. We describe a new anodic design that uses an uninsulated portion of the metallic tether itself to collect electrons. Because of the efficient collection of this type of anode, electrodynamic thrusters for reboost of the International Space Station and for an upper stage capable of orbit raising, lowering, and inclination changes appear to be feasible. Specifically, a 10-km-long bare tether, utilizing 10 kW of the space station power could save most of the propellant required for the station reboost over its 10-year lifetime, The propulsive small expendable deployer system experiment is planned to test the bare-tether design in space in the year 2000 by deploying a 5-km bare aluminum tether from a Delta II upper stage to achieve up to 0.5-N drag thrust, thus deorbiting the stage. C1 Harvard Smithsonian Ctr Astrophys, Radio & Geoastron Div, Cambridge, MA 02138 USA. Univ Politecn Madrid, Escuela Super Ingn Aeronaut, E-28040 Madrid, Spain. MIT, Cambridge, MA 02139 USA. NASA, George C Marshall Space Flight Ctr, Adv Space Transportat Res Program, Huntsville, AL 35812 USA. Boeing Co, Huntsville, AL 35824 USA. RP Estes, RD (reprint author), Harvard Smithsonian Ctr Astrophys, Radio & Geoastron Div, MS 80,60 Garden St, Cambridge, MA 02138 USA. NR 24 TC 30 Z9 31 U1 2 U2 12 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 MAR-APR PY 2000 VL 37 IS 2 BP 205 EP 211 DI 10.2514/2.3567 PG 7 WC Engineering, Aerospace SC Engineering GA 302XC UT WOS:000086390900008 ER PT J AU Severson, K Koob, S Wolfe, J Shoe, P Hornbeck, S Howarth, SM Sigel, A AF Severson, K Koob, S Wolfe, J Shoe, P Hornbeck, S Howarth, SM Sigel, A TI Recovery of unbacked mosaics from a storage depot fire at the Sardis excavations, Turkey SO JOURNAL OF THE AMERICAN INSTITUTE FOR CONSERVATION LA English DT Article AB On the night of June 19, 1997, the on-site mosaic depot at Sardis, Turkey, burned, entirely destroying the wooden roof. Two stacks of lifted mosaic sections, already faced with animal glue and cotton, were stored in the depot and were covered by the resulting debris of charcoal, ash, and exploded ceramic roof tiles. Each stack consisted of four mosaic sections lying on top of each other, separated by plastic sheeting and layers of paper that melted and burned on the top and sides. Initial recovery of the damaged and buried mosaics was undertaken by the team of conservators and conservation students already on-site for the regular excavation season. Removal of large and small debris was carried out, and periodic assessments were made to decide final methods of cleaning and separation of the damaged layers. Secondary recovery was undertaken in the 1998 season. Two methods of recovery were tested: first by lining damaged layers with cotton cloth and acrylic emulsion, and second by securing portions of a stack with polyurethane foam, flipping the stack, and removing layers from the reverse. Recovery will continue during the 1999 season. C1 Corning Museum Glass, Corning, NY 14830 USA. Guggenheim Museum Art, New York, NY USA. Smithsonian Inst, Washington, DC 20560 USA. Metropolitan Museum Art, New York, NY 10028 USA. Harvard Univ, Cambridge, MA 02138 USA. RP Koob, S (reprint author), Corning Museum Glass, Corning, NY 14830 USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU AMER INST CONSERVATION HISTORIC ARTISTIC WORKS PI WASHINGTON PA 1717 K ST, NW, STE 301, WASHINGTON, DC 20006 USA SN 0197-1360 J9 J AM INST CONSERV JI J. Am. Inst. Conserv. PD SPR PY 2000 VL 39 IS 1 BP 3 EP 13 DI 10.2307/3179960 PG 11 WC Humanities, Multidisciplinary SC Arts & Humanities - Other Topics GA 322KX UT WOS:000087509700002 ER PT J AU Deucher, VM Moore, TL Hemlin, S AF Deucher, VM Moore, TL Hemlin, S TI Access denied: Asbestos contamination as catalyst and hindrance to collection retrieval and preservation SO JOURNAL OF THE AMERICAN INSTITUTE FOR CONSERVATION LA English DT Article AB Asbestos abatement industry standards for items exposed to a contaminated environment generally call for disposal. This option is not acceptable for museum objects that have been contaminated by asbestos. For many years the Smithsonian Institution has worked to define and refine artifact asbestos decontamination procedures and approaches. The Building 17 Artifact Asbestos Decontamination Project plan was developed through a series of institution-wide meetings that ensured sufficient staff and other resources existed to meet contractual obligations and that provided a clear work process under which the project could proceed. After the project started, the plan, which was always considered to be dynamic, was altered to accommodate the many known and unknown challenges and hazards discovered within the space. Working with collections at risk forced the museum to make difficult collections management and preservation decisions and to remain dynamic and flexible in the management of the project. The purpose of this article is to review the planning process, to examine the balance of decontamination methods with preservation practices, to discuss the various decontamination protocols planned, and to outline the differences between what had been planned and what was discovered during implementation. C1 Smithsonian Inst, Natl Museum Am Hist, Suitland, MD 20746 USA. Amer Museum Nat Hist, Washington, DC 20560 USA. RP Deucher, VM (reprint author), Smithsonian Inst, Natl Museum Am Hist, PE Garber Fac Bldg 18 3904 Old Silver Hill Rd, Suitland, MD 20746 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER INST CONSERVATION HISTORIC ARTISTIC WORKS PI WASHINGTON PA 1717 K ST, NW, STE 301, WASHINGTON, DC 20006 USA SN 0197-1360 J9 J AM INST CONSERV JI J. Am. Inst. Conserv. PD SPR PY 2000 VL 39 IS 1 BP 75 EP 84 DI 10.2307/3179965 PG 10 WC Humanities, Multidisciplinary SC Arts & Humanities - Other Topics GA 322KX UT WOS:000087509700007 ER PT J AU Reinert, JF AF Reinert, JF TI Synonymy of subgenus Sinoaedes of genus Aedes with subgenus Mattinglyia of genus Heizmannia SO JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION LA English DT Article DE Sinoaedes; Heizmannia; Mattinglyia; Heizmannia occidentayunnana; mosquito AB The subgenus Sinoaedes is transferred from the genus Aedes and placed in synonymy with the subgenus Mattinglyia of the genus Heizmannia. The haplotype of Sinoaedes, Aedes occidentayunnanus, is transferred to the subgenus Mattinglyia of the genus Heizmannia and the spelling of the specific name is corrected to agree in gender with Heizmannia. Rationale for these actions is provided. C1 USDA ARS, Ctr Med Agr & Vet Entomol, Gainesville, FL 32608 USA. Smithsonian Inst, Walter Reed Biosystemat Unit, Washington, DC 20560 USA. RP Reinert, JF (reprint author), USDA ARS, Ctr Med Agr & Vet Entomol, 1600-1700 SW 23rd Dr, Gainesville, FL 32608 USA. NR 8 TC 4 Z9 5 U1 0 U2 0 PU AMER MOSQUITO CONTROL ASSOC PI MOUNT LAUREL PA 15000 COMMERCE PARKWAY, SUITE C, MOUNT LAUREL, NJ 08054 USA SN 8756-971X EI 1943-6270 J9 J AM MOSQUITO CONTR JI J. Am. Mosq. Control Assoc. PD MAR PY 2000 VL 16 IS 1 BP 38 EP 39 PG 2 WC Entomology SC Entomology GA 298PT UT WOS:000086148900009 PM 10757490 ER PT J AU Reinert, JF AF Reinert, JF TI Assignment of two North American species of Aedes to subgenus Rusticoidus SO JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION LA English DT Article DE Rusticoidus; Aedes bicristatus; Aedes provocans; mosquito AB Aedes bicristatus and Aedes provocans ore transferred to subgenus Rusticoidus from subgenus Ochlerotatus. Primary morphologic features of Rusticoidus are provided for separating this subgenus from all other subgenera of genus Aedes. C1 USDA ARS, Ctr Med Agr & Vet Entomol, Gainesville, FL 32608 USA. Smithsonian Inst, Walter Rees Biosystemat Unit, Washington, DC 20560 USA. RP Reinert, JF (reprint author), USDA ARS, Ctr Med Agr & Vet Entomol, 1600-1700 SW 23rd Dr, Gainesville, FL 32608 USA. NR 10 TC 2 Z9 2 U1 0 U2 1 PU AMER MOSQUITO CONTROL ASSN INC PI LAKE CHARLES PA 2200 E PRIEN LAKE RD, LAKE CHARLES, LA 70601 USA SN 8756-971X J9 J AM MOSQUITO CONTR JI J. Am. Mosq. Control Assoc. PD MAR PY 2000 VL 16 IS 1 BP 42 EP 43 PG 2 WC Entomology SC Entomology GA 298PT UT WOS:000086148900011 PM 10757492 ER PT J AU Furth, DG Lee, JE AF Furth, DG Lee, JE TI Similarity of the Blepharida-group genera using larval and adult characters (Coleoptera : Chrysomelidae : Alticinae) SO JOURNAL OF THE NEW YORK ENTOMOLOGICAL SOCIETY LA English DT Article AB Adult and mature larval characters df Blepharida atripennis, B. rhois, B. sacra, Diamphidia sp., Euplectroscelis xanti, Ophrida marmorea Podontia affinis, P. lutea and P. dalmani, were studied as representatives of their respective genera or subgenera from the Blepharida-Group of approximately 16 genera worldwide, presumed to be related. The similarities and relationships of these and other genera based on adult and larval morphology and biology are discussed. The mature larvae of these nine species are illustrated in detail, three for the first time (Ophrida marmorea, Euplectroscelis xanti, and Diamphidia sp.). Adult external morphology and the metafemoral spring were compared and indicated several overlapping similarities. Some discussion of the classification of the Galerucinae and Alticinae is provided. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Entomol, Washington, DC 20560 USA. RP Furth, DG (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Entomol, Washington, DC 20560 USA. NR 33 TC 12 Z9 12 U1 0 U2 3 PU NEW YORK ENTOMOLOGICAL SOC INC PI NEW YORK PA C/O AMER MUSEUM NAT HIST 79TH & CENTRAL PARK WEST, NEW YORK, NY 10024 USA SN 0028-7199 J9 J NEW YORK ENTOMOL S JI J. N.Y. Entomol. Soc. PD SPR-SUM PY 2000 VL 108 IS 1-2 BP 26 EP 51 DI 10.1664/0028-7199(2000)108[0026:SOTBGG]2.0.CO;2 PG 26 WC Entomology SC Entomology GA 388YH UT WOS:000166210300003 ER PT J AU Harms, KE Dalling, JW AF Harms, KE Dalling, JW TI A bruchid beetle and a viable seedling from a single diaspore of Attalea butyracea SO JOURNAL OF TROPICAL ECOLOGY LA English DT Article DE Arecaceae; Attalea butyracea; Barro Colorado Island; Bruchidae; germination; Panama; Scheelea rostrata; Scheelea zonensis; seed; seed-predator ID SCHEELEA PALM SEEDS; DAMAGE TOLERANCE; WIND DISPERSAL; PARENT PALM; PREDATION; SURVIVAL; DISTANCE; FRUITS; NUMBER; PANAMA C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Calif Santa Barbara, Dept Ecol Evolut & Marine Biol, Santa Barbara, CA 93106 USA. RP Harms, KE (reprint author), Univ Calif Santa Barbara, Dept Ecol Evolut & Marine Biol, Santa Barbara, CA 93106 USA. NR 17 TC 9 Z9 12 U1 0 U2 2 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0266-4674 J9 J TROP ECOL JI J. Trop. Ecol. PD MAR PY 2000 VL 16 BP 319 EP 325 DI 10.1017/S0266467400001425 PN 2 PG 7 WC Ecology SC Environmental Sciences & Ecology GA 308BX UT WOS:000086689600009 ER PT J AU Bush, M Stoskopf, MK Raath, JP Papich, MG AF Bush, M Stoskopf, MK Raath, JP Papich, MG TI Serum oxytetracycline concentrations in African elephant (Loxodonta africana) calves after long-acting formulation injection SO JOURNAL OF ZOO AND WILDLIFE MEDICINE LA English DT Article DE African elephant; Loxodonta africana; oxytetracycline; serum drug concentrations; pharmacokinetics ID PHARMACOKINETICS; EFFICACY AB Serum oxytetracycline pharmacokinetics were studied in 18 African elephant (Loxodonta africana) calves. Each elephant received separate injections of oxytetracycline at approximately 18 mg/kg i.m. and 8 mg/kg i.v. in a cross-over study. Blood samples were drawn at 0, 24, 48, 72, and 96 hr postinjection. An additional sample was drawn 110 hr before the animals were reinjected in the cross-over study and a final blood sample was drawn 48 hr after the second dose. No lameness or stiffness was observed following i.m. injections. Serum oxytetracycline concentrations >0.5 mu g/ml were present 48 hr after initial dosing for all elephants (i.m., i.v., high or low dosage). Only elephants given the high i.m. dosage (18 mg/kg) maintained levels >0.5 mu g/ml 72 hr postinjection. No significant difference in serum oxytetracycline concentration with time was observed between the groups given different i.v. dosages. These studies demonstrated that quantifiable serum oxytetracycline concentrations can be maintained in young African elephants with a low-dosage multidose i.m. regimen. C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. N Carolina State Univ, Coll Vet Med, Environm Med Consortium, Raleigh, NC 27606 USA. Kruger Natl Pk, Natl Pk Board, ZA-1350 Skukuza, South Africa. RP Bush, M (reprint author), Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. NR 22 TC 7 Z9 7 U1 0 U2 4 PU AMER ASSOC ZOO VETERINARIANS PI MEDIA PA 6 NORTH PENNELL ROAD, MEDIA, PA 19063 USA SN 1042-7260 J9 J ZOO WILDLIFE MED JI J. Zoo Wildl. Med. PD MAR PY 2000 VL 31 IS 1 BP 41 EP 46 PG 6 WC Veterinary Sciences SC Veterinary Sciences GA 326AJ UT WOS:000087709300007 PM 10884122 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI Heaven. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Libs, Washington, DC 20560 USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Libs, Washington, DC 20560 USA. NR 1 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 MAR 1 PY 2000 VL 125 IS 4 BP 84 EP 84 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 291CY UT WOS:000085717600035 ER PT J AU Franklin, F Lecar, M AF Franklin, F Lecar, M TI On the transport of bodies within and from the asteroid belt SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID SECULAR RESONANCE; SOLAR NEBULA; BEHAVIOR AB This paper explores two processes, sweeping secular resonance (Ward, 1981) and gas drag (Lecar and Franklin, 1997), at work during the dispersal of the solar nebula. We have two aims not previously considered for the two mechanisms: (1) to explain the likely depletion, by a factor of 1000 or so, of the rocky material in the inner belt (2.0 < a < 3.2 AU); (2) to introduce a means for providing-or contributing to-the dispersion in semimajor axis of the various asteroidal taxonomic classes. We suggest that large asteroids with birthplaces separated by an astronomical unit or more can be finally deposited, owing to drag, at the same semimajor axis. For example, we find that bodies with radii up to 100 km can be transferred by gas drag from the outer belt (a > 3.3 AU) well into the inner one, and that an object already in the inner belt as large or even larger than Vesta (r = 250 km)-thought to be the parent body of many meteorites-can be inwardly displaced by as much as an astronomical unit if the nebula dispersal times lie close to 10(5) years. For such times, a large fraction of the inner belt's primordial mass can be ejected, with most of it passing into the inner solar system. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Franklin, F (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 21 TC 11 Z9 11 U1 1 U2 1 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD MAR PY 2000 VL 35 IS 2 BP 331 EP 340 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 297WG UT WOS:000086105200009 ER PT J AU Marsh, DM Rand, AS Ryan, MJ AF Marsh, DM Rand, AS Ryan, MJ TI Effects of inter-pond distance on the breeding ecology of tungara frogs SO OECOLOGIA LA English DT Article DE site fidelity; aggregation; oviposition site selection; tungara frog; Physalaemus pustulosus ID OVIPOSITION SITES; PHYSALAEMUS-PUSTULOSUS; SEXUAL SELECTION; NEOTROPICAL FROG; CHOICE; ADVERTISEMENT; ANURAN; AMPHIBIANS; PREDATION; BEHAVIOR AB Habitat and resource distributions can influence the movement and aggregation of individuals and thus have important effects on breeding behavior and ecology. Though amphibians have been model systems for the study of breeding behavior and sexual selection, most studies have examined breeding behavior within a single pond. As a result, little is known about how inter-pond distance affects breeding amphibians. We studied the effects of inter-pond distance on the breeding ecology of the tungara frog, Physalaemus pustulosus, in replicated pond arrays in which distance was varied from 0 to 50 m. We predicted that male site fidelity and male aggregation within arrays would increase with inter-pond distance, and that the opportunity for mate choice and oviposition site selectivity by females would decrease with the distance between ponds. Male site fidelity did increase with inter-pond distance. However, male aggregation decreased with distance, such that males tended to be more evenly spaced among ponds when ponds were farther apart. The opportunity for mate choice by females, measured as the number of males within the phonotactic radius of females, also decreased with inter-pond distance. Each of these three responses was consistent with a threshold effect between 5 m and 10 m in inter-pond distance. This threshold corresponded to the maximum distance at which females in laboratory choice experiments exhibited phonotaxis toward the "whine" call of a tungara male, suggesting that phonotactic limits may play an important role in tungara movements and spacing patterns. The distribution of egg masses among ponds, a potential correlate of oviposition site selectivity, did not vary with inter-pond distance. Multiple egg masses deposited on the same night were significantly overdispersed in all distance treatments, implying that females may select oviposition sites to avoid conspecific egg masses over distances of at least 50 m. Collectively, these results demonstrate that inter-pond distance may indeed affect amphibian breeding and movement behavior, and that consideration of multiple habitat patches and their spatial distributions can provide new insights into even the most well-understood mating systems. C1 Univ Calif Davis, Dept Environm Sci & Policy, Davis, CA 95616 USA. Univ Calif Davis, Ctr Populat Biol, Davis, CA 95616 USA. Smithsonian Trop Res Inst, APO, AA 34002 USA. Univ Texas, Dept Zool, Austin, TX 78712 USA. RP Marsh, DM (reprint author), Univ Calif Davis, Dept Environm Sci & Policy, Wickson Hall,1 Shields Ave, Davis, CA 95616 USA. EM dmmarsh@ucdavis.edu NR 55 TC 29 Z9 33 U1 1 U2 14 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0029-8549 EI 1432-1939 J9 OECOLOGIA JI Oecologia PD MAR PY 2000 VL 122 IS 4 BP 505 EP 513 DI 10.1007/s004420050973 PG 9 WC Ecology SC Environmental Sciences & Ecology GA 303YG UT WOS:000086455000009 PM 28308343 ER PT J AU Mair, RW Tseng, CH Wong, GP Cory, DG Walsworth, RL AF Mair, RW Tseng, CH Wong, GP Cory, DG Walsworth, RL TI Magnetic resonance imaging of convection in laser-polarized xenon SO PHYSICAL REVIEW E LA English DT Article ID NOBLE-GAS; PGSE NMR; MICROSCOPY; FLOW; MRI AB We demonstrate nuclear magnetic resonance (NMR) imaging of the flow and diffusion of laser-polarized xenon (Xe-129) gas undergoing convection above evaporating laser-polarized liquid xenon. The large xenon NMR signal provided by the laser-polarization technique allows more rapid imaging than one can achieve with thermally polarized gas-liquid systems, permitting shorter time-scale events such as rapid gas flow and gas-liquid dynamics to be observed. Two-dimensional velocity-encoded imaging shows convective gas flow above the evaporating liquid xenon, and also permits the measurement of enhanced gas diffusion near regions of large velocity variation. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. RP Mair, RW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. FU FDA HHS [BES-9612237] NR 25 TC 21 Z9 21 U1 0 U2 3 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 MAR PY 2000 VL 61 IS 3 BP 2741 EP 2748 DI 10.1103/PhysRevE.61.2741 PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 295XM UT WOS:000085994000078 PM 11046596 ER PT J AU Gardner, JB Trask, DF AF Gardner, JB Trask, DF TI Serving time in the trenches: David F. Trask, public historian and federal historian SO PUBLIC HISTORIAN LA English DT Editorial Material ID GOVERNMENT C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Gardner, JB (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA C/O JOURNALS DIVISION, 2000 CENTER ST, STE 303, BERKELEY, CA 94704-1223 USA SN 0272-3433 J9 PUBL HISTORIAN JI Public Hist. PD SPR PY 2000 VL 22 IS 2 BP 9 EP + PG 0 WC History SC History GA 322VD UT WOS:000087528900002 ER PT J AU Worthington, WE AF Worthington, WE TI Stay Cool! Air conditioning America SO PUBLIC HISTORIAN LA English DT Art Exhibit Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Worthington, WE (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA C/O JOURNALS DIVISION, 2000 CENTER ST, STE 303, BERKELEY, CA 94704-1223 USA SN 0272-3433 J9 PUBL HISTORIAN JI Public Hist. PD SPR PY 2000 VL 22 IS 2 BP 116 EP 117 PG 2 WC History SC History GA 322VD UT WOS:000087528900025 ER PT J AU Odo, F AF Odo, F TI 'Rabbit in the Moon' SO PUBLIC HISTORIAN LA English DT Film Review C1 Smithsonian Inst, Asian Pacific Amer Studies Program, Washington, DC 20560 USA. RP Odo, F (reprint author), Smithsonian Inst, Asian Pacific Amer Studies Program, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA C/O JOURNALS DIVISION, 2000 CENTER ST, STE 303, BERKELEY, CA 94704-1223 USA SN 0272-3433 J9 PUBL HISTORIAN JI Public Hist. PD SPR PY 2000 VL 22 IS 2 BP 123 EP 124 PG 2 WC History SC History GA 322VD UT WOS:000087528900028 ER PT J AU Barton, EJ Kannappan, SJ Kurtz, MJ Geller, MJ AF Barton, EJ Kannappan, SJ Kurtz, MJ Geller, MJ TI Rotation curve measurement using cross-correlation SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID SPIRAL GALAXIES; ELLIPTIC GALAXIES; VELOCITIES; REDSHIFTS; DISKS AB Long-slit spectroscopy is entering an era of increased spatial and spectral resolution and increased sample size. Improved instruments reveal complex: velocity structure that cannot be, described with a one-dimensional rotation curve, yet samples are too numerous to examine each galaxy in detail. Therefore, one goal of rotation curve measurement techniques is to flag cases in which the kinematic structure of the galaxy is more complex than a single-valued curve. We examine cross-correlation as a technique that is easily automated and works for low signal-to-noise spectra. We show that the technique yields well-defined errors which increase when the simple spectral model (template) is a poor match to the data, flagging those cases for later inspection. We compare the technique to the more traditional, parametric technique of simultaneous emission-line fitting. When the line profile at a single slit position is non-Gaussian, the techniques disagree. For our model spectra with two well-separated velocity components, assigned velocities from the two techniques differ by up to similar to 52% of the velocity separation of the model components. However, careful use of the error statistics for either technique allows one to flag these non-Gaussian spectra. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Barton, EJ (reprint author), Dominion Astrophys Observ, Herzberg Inst Astrophys, Natl Res Council Canada, Dominion Astrophys Observ, 5071 W Saanich Rd,RR5, Victoria, BC V8X 4M6, Canada. RI KURTZ, Michael /B-3890-2009; OI Kurtz, Michael/0000-0002-6949-0090 NR 26 TC 6 Z9 6 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD MAR PY 2000 VL 112 IS 769 BP 367 EP 383 DI 10.1086/316533 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 292HQ UT WOS:000085788900012 ER PT J AU Dudley, R AF Dudley, R TI Evolutionary origins of human alcoholism in primate frugivory SO QUARTERLY REVIEW OF BIOLOGY LA English DT Review ID DROSOPHILA-MELANOGASTER; DENTAL MICROWEAR; LOWLAND GORILLAS; FLESHY FRUITS; DEHYDROGENASE POLYMORPHISM; METABOLIZING GENES; PAN-TROGLODYTES; SEED DISPERSAL; KIBALE FOREST; LOPE RESERVE AB Evolutionary origins of alcohol consumption have rarely been considered in studies of ethanol addiction. However, the occurrence of ethanol in ripe and decaying fruit and the substantial heritability of alcoholism in humans suggest an important historical association between primate frugivory and alcohol consumption. Olfactory localization of ripe fruit via volatilized alcohols, the use of ethanol as an appetitive stimulant, and the consumption of fruits with substantial ethanol content potentially characterize all frugivorous primates, including hominoids and the lineage leading to modem humans. Patterns of alcohol use by humans in contemporary environments nay thus reflect a maladaptive co-option of ancestral nutritional strategies. Although diverse factors contribute to the expression of alcoholism as a clinical syndrome, historical selection for the consumption of ethanol in the course of frugivory can be viewed as a subtle get pervasive evolutionary influence on modern humans. C1 Univ Texas, Sect Integrat Biol, Austin, TX 78712 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Dudley, R (reprint author), Univ Texas, Sect Integrat Biol, Austin, TX 78712 USA. EM R_DUDLEY@UTXVMS.CC.UTEXAS.EDU NR 154 TC 54 Z9 56 U1 1 U2 25 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0033-5770 J9 Q REV BIOL JI Q. Rev. Biol. PD MAR PY 2000 VL 75 IS 1 BP 3 EP 15 DI 10.1086/393255 PG 13 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 287RF UT WOS:000085519200001 PM 10721531 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI African-American culture and history on CD-ROM. SO REFERENCE & USER SERVICES QUARTERLY LA English DT Database Review C1 Smithsonian Inst Lib, Washington, DC USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Lib, Washington, DC USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER LIBRARY ASSOC PI CHICAGO PA 50 E HURON ST, CHICAGO, IL 60611 USA SN 1094-9054 J9 REF USER SERV Q JI Ref. User Serv. Q. PD SPR PY 2000 VL 39 IS 3 BP 286 EP 286 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 327NX UT WOS:000087800900013 ER PT J AU Robinson, H Panero, J AF Robinson, H Panero, J TI Five new species of Verbesina from the northern Andes (Heliantheae; Asteraceae) SO RHODORA LA English DT Article DE Verbesina; new species; Heliantheae; Asteraceae; Ecuador; Colombia; northern Andes AB Five new species of Verbesina are described, V. biserrata, V. clarkae, V. maldonadoensis, and V. pichinchensis all from Ecuador, and V. perijaensis from Colombia. C1 Natl Museum Nat Hist, Dept Bot, Smithsonian Inst, Washington, DC 20560 USA. RP Robinson, H (reprint author), Natl Museum Nat Hist, Dept Bot, Smithsonian Inst, Washington, DC 20560 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU NEW ENGLAND BOTANICAL CLUB INC PI LAWRENCE PA P.O. BOX 368, LAWRENCE, KS 66044 USA SN 0035-4902 J9 RHODORA JI Rhodora PD SPR PY 2000 VL 102 IS 910 BP 129 EP 141 PG 13 WC Plant Sciences SC Plant Sciences GA 322TB UT WOS:000087523900001 ER PT J AU Raymond, JT Tell, L Bush, M Nichols, DK Schulman, FY Montali, RJ AF Raymond, JT Tell, L Bush, M Nichols, DK Schulman, FY Montali, RJ TI Subcutaneous atypical mycobacteriosis in captive tiger quolls (Dasyurus maculatus) SO VETERINARY PATHOLOGY LA English DT Article DE atypical mycobacteriosis; cellulitis; group IV mycobacteria; panniculitis; skin; tiger quolls ID RAPIDLY GROWING MYCOBACTERIA; POSSUM TRICHOSURUS-VULPECULA; AUGMENTATION MAMMAPLASTY; FORTUITUM COMPLEX; WOUND INFECTIONS; BOVIS; ORGANISMS; SURGERY; CATS AB From July 1989 to October 1998, 9/37 (24%) adult captive tiger quells (Dasyurus maculatus) were diagnosed with atypical mycobacterial infection involving the subcutis and skin. Females were more often affected than males (seven females, two males). Grossly, lesions presented as focal thickenings, plaques, and abscesses within the subcutis, often with fistulous tracts. The subcutis and skin overlying cervical and thoracic regions were the primary sites of infection. Cytology of subcutaneous impression smears from all nine affected tiger quells revealed pyogranulomatous inflammation admired with several acid-fast bacilli. Histologically, all tiger quells had nodular to diffuse pyogranulomatous panniculitis and cellulitis. Small numbers of acid-fast bacilli were noted histologically in 7/9 (78%) animals. Skin cultures from seven tiger quells were positive for one or more different Runyon group IV mycobacteria. The disease described in these tiger quells is similar to subcutaneous atypical mycobacteriosis of humans and domestic animals. C1 Smithsonian Inst, Natl Zool Pk, Dept Pathol, Washington, DC 20008 USA. Univ Calif Davis, Sch Vet Med, Dept Med & Epidemiol, Davis, CA USA. Natl Zool Pk, Conservat & Res Ctr, Vet Serv, Front Royal, VA USA. USAF, Inst Pathol, Dept Vet Pathol, Washington, DC 20330 USA. RP Raymond, JT (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Pathol, 3000 Connecticut Ave NW, Washington, DC 20008 USA. NR 38 TC 9 Z9 9 U1 0 U2 3 PU AMER COLL VET PATHOLOGIST PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 USA SN 0300-9858 J9 VET PATHOL JI Vet. Pathol. PD MAR PY 2000 VL 37 IS 2 BP 137 EP 142 DI 10.1354/vp.37-2-137 PG 6 WC Pathology; Veterinary Sciences SC Pathology; Veterinary Sciences GA 291UL UT WOS:000085754600003 PM 10714642 ER PT J AU Warkentin, IG Morton, ES AF Warkentin, IG Morton, ES TI Flocking and foraging behavior of wintering Prothonotary Warblers SO WILSON BULLETIN LA English DT Article ID MIXED-SPECIES FLOCKS; VENEZUELAN MANGROVES; FEEDING-BEHAVIOR; WOODLAND; BIRDS; TITS; ADVANTAGES; PATTERNS; ECOLOGY AB We quantified flocking behavior and examined the impact of social context (solitary, single species flocks, and mixed-species flocks) on the foraging behavior of Prothonotary Warblers (Protonotaria citrea) wintering in a Costa Rican mangrove forest and surrounding habitats. Based on observations collected over two winters during 70 visits to four sites, 87% (483) of the 555 Prothonotary Warblers encountered moved in hocks and over 48% (271) of these individuals were in single-species flocks. Although the propensity to join Rocks was 6% higher for Prothonotary Warblers in the second winter of the study, neither the average size of single-species flocks nor the average number of individuals or species in mixed-species flocks differed between years. Twenty-seven different species were identified in mixed-species Rocks that had at least one Prothonotary Warbler, but Nearctic migrants dominated these flocks. Analyses of focal observations on 57 females and 93 males indicated that Prothonotary Warbler foraging behavior was largely independent of flock type and size. Foraging maneuver, substrate, and location did not differ significantly for individuals of either sex foraging alone, in single-species, or mixed-species flocks. The species is almost strictly insectivorous, gleaning made up 70% of 150 prey capture attempts observed and about half of all attempts (76 of 150) were directed towards leaf surfaces. Foraging generally occurred in the outer third of the tree, on branches less than 1 cm in diameter, in the bottom half of the canopy. Agonistic interactions among flock members that involved Prothonotary Warblers were uncommon and neither fleck type nor size were useful predictors for rates of foraging, movement, preening, or vigilance. C1 Mem Univ Newfoundland, Sir Wilfred Grenfell Coll, Corner Brook, NF A2H 6P9, Canada. Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. RP Warkentin, IG (reprint author), Mem Univ Newfoundland, Sir Wilfred Grenfell Coll, Corner Brook, NF A2H 6P9, Canada. NR 47 TC 11 Z9 11 U1 2 U2 12 PU WILSON ORNITHOLOGICAL SOC PI ANN ARBOR PA MUSEUM OF ZOOLOGY UNIV MICHIGAN, ANN ARBOR, MI 48109 USA SN 0043-5643 J9 WILSON BULL JI Wilson Bull. PD MAR PY 2000 VL 112 IS 1 BP 88 EP 98 DI 10.1676/0043-5643(2000)112[0088:FAFBOW]2.0.CO;2 PG 11 WC Ornithology SC Zoology GA 289ZZ UT WOS:000085653000012 ER PT J AU Sharrer, T AF Sharrer, T TI Breaking down cancer SO SCIENTIST LA English DT Editorial Material C1 Smithsonian Inst, Washington, DC 20560 USA. RP Sharrer, T (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SCIENTIST INC PI PHILADELPHIA PA 3600 MARKET ST SUITE 450, PHILADELPHIA, PA 19104 USA SN 0890-3670 J9 SCIENTIST JI Scientist PD FEB 21 PY 2000 VL 14 IS 4 BP 39 EP 39 PG 1 WC Information Science & Library Science; Multidisciplinary Sciences SC Information Science & Library Science; Science & Technology - Other Topics GA 293KR UT WOS:000085851200026 ER PT J AU Barton, EJ Geller, MJ Kenyon, SJ AF Barton, EJ Geller, MJ Kenyon, SJ TI Tidally triggered star formation in close pairs of galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : clusters : general; galaxies : interactions; galaxies : stellar content; stars : luminosity function, mass function ID PISCES-PERSEUS SUPERCLUSTER; CFA REDSHIFT SURVEY; 21 CM SURVEY; INTERACTING GALAXIES; INFRARED GALAXIES; SPIRAL GALAXIES; MERGING GALAXIES; FORMATION RATES; SPECTROPHOTOMETRIC STANDARDS; OPTICAL SPECTROSCOPY AB We analyze optical spectra of a sample of 502 galaxies in close pairs and N-tuples, separated by less than or equal to 50 h(-1) kpc. We extracted the sample objectively from the CfA2 redshift survey, without regard to the surroundings of the tight systems; we remeasure the spectra with longer exposures, to explore the spectral characteristics of the galaxies. We use the new spectra to probe the relationship between star formation and the dynamics of the systems of galaxies. The equivalent widths of H alpha [EW(H alpha)] and other emission lines anticorrelate strongly with pair spatial separation (Delta D) and velocity separation; the anticorrelations do not result from any large-scale environmental effects that we detect. We use the measured EW(Hcl) and the starburst models of Leitherer et al. to estimate the time since the most recent burst of star formation began for galaxies in our sample. In the absence of a large contribution from an old stellar population to the continuum around H alpha that correlates with the orbit parameters, the observed Delta D-EW(H alpha) correlation signifies that starbursts with larger separations on the sky are, on average, older. We also find a population of galaxies with small to moderate amounts of Balmer absorption. These galaxies support our conclusion that the sample includes many aging bursts of star formation; they have a narrower distribution of velocity separations, consistent with a population of orbiting galaxies near apogalacticon. By matching the dynamical timescale to the burst timescale, we show that the data support a simple picture in which a close pass initiates a starburst; EW(H alpha) decreases with time as the pair separation increases, accounting for the anticorrelation. Recent N-body/smoothed particle hydrodynamics simulations of interacting pairs suggest a physical basis for the correlation-for galaxies with shallow central potentials, they predict gas infall before the final merger. This picture leads to a method for measuring the duration and the initial mass function of interaction-induced starbursts: our data are compatible with the starburst models and orbit models in many respects, as long as the starburst lasts longer than similar to 10(8) yr and the delay between the close pass and the initiation of the starburst is less than a few times 10(7) yr. If there is no large contribution from an old stellar population to the continuum around H alpha, the Miller-Scale and cutoff (M less than or equal to 30 M.) Salpeter initial mass functions (IMFs) fit the data much better than a standard Salpeter IMF. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Barton, EJ (reprint author), Natl Res Council Canada, Herzberg Inst Astrophys, Dominion Astrophys Observ, 5-71 W Saanich Rd,RR5, Victoria, BC V8X 4M6, Canada. OI Kenyon, Scott/0000-0003-0214-609X NR 77 TC 228 Z9 229 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP 660 EP 679 DI 10.1086/308392 PN 1 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500008 ER PT J AU Worrall, DM Birkinshaw, M AF Worrall, DM Birkinshaw, M TI X-ray-emitting atmospheres of B2 radio galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; radiation mechanisms : nonthermal; radio continuum : galaxies; X-rays : galaxies ID VLA OBSERVATIONS; ROSAT OBSERVATIONS; SAMPLE; ENVIRONMENT; EMISSION AB We report ROSAT PSPC spatial and spectral analyses of the eight B2 radio galaxies NGC 315, NGC 326, 4C 35.03, B2 0326+39, NGC 2484, B2 1040+31, B2 1855+37, and 3C 449, expected to be representative of the class of low-power radio galaxies. Multiple X-ray components are present in each, and the gas components have a wide range of linear sizes and follow an extrapolation of the cluster X-ray luminosity/temperature correlation, implying that there is no relationship between the presence of a radio galaxy and the gas fraction of the environment. No large-scale cooling flows are found. There is no correlation of radio-galaxy size with the scale or density of the X-ray atmosphere. This suggests that processes on scales smaller than those of the overall gaseous environments are the major influence on radio-source dynamics. The intergalactic medium is usually sufficient to confine the outer parts of the radio structures, in some cases even to within 5 kpc of the core. In the case of NGC 315, an extrapolation suggests that the pressure of the atmosphere may match the minimum pressure in the radio source over a factor of similar to 40 in linear size (a factor of similar to 1600 in pressure). C1 Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Worrall, DM (reprint author), Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. NR 34 TC 59 Z9 59 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP 719 EP 732 DI 10.1086/308411 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500012 ER PT J AU Kalogera, V Lorimer, DR AF Kalogera, V Lorimer, DR TI An upper limit on the coalescence rate of double neutron-star binaries in the Galaxy SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; pulsars : general; stars : neutron ID ASYMMETRIC SUPERNOVA EXPLOSIONS; RADIO PULSARS; INTRINSIC KICKS; BEAMS; EVOLUTION; SYSTEMS; STATISTICS; BIRTHRATE; DYNAMICS; VELOCITY AB In the context of assessing the detectability of the coalescence of two neutron stars (NS) by currently built gravitational wave experiments, we present a way of obtaining an upper limit to the coalescence rate in the Galaxy. We consider the NS/NS progenitors just before the second supernova explosion. We combine the theoretical understanding of orbital dynamics at NS formation with methods of empirically estimating pulsar birth rates and derive an upper limit of a few mergers every 10(5) yr. Such a Galactic rate implies a possible detection by the "enhanced" LIGO of up to a few to 10 mergers per year. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Arecibo Observ, Arecibo, PR 00612 USA. RP Kalogera, V (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM vkalogera@cfa.harvard.edu; dunc@naic.edu NR 41 TC 37 Z9 37 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 FEB 20 PY 2000 VL 530 IS 2 BP 890 EP 895 DI 10.1086/308417 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500026 ER PT J AU Delamarter, G Frank, A Hartmann, L AF Delamarter, G Frank, A Hartmann, L TI Interaction of infall and winds in young stellar objects SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; stars : pre-main-sequence; stars : winds, outflows ID MAGNETOCENTRIFUGALLY DRIVEN FLOWS; MOLECULAR OUTFLOWS; NUMERICAL SIMULATIONS; PROTOSTELLAR COLLAPSE; ACCRETION DISKS; MIXING LAYERS; JETS; MODELS; STARS; COLLIMATION AB The interaction of a stellar or disk wind with a collapsing environment holds promise for explaining a variety of outflow phenomena observed around young stars. In this paper we present the first simulations of these interactions. The focus here is on exploring how ram pressure balance between wind and ambient gas and postshock cooling affects the shape of the resulting outflows. In our models we explore the role of ram pressure and cooling by holding the wind speed constant and adjusting the ratio of the inflow mass flux to the wind mass flux ((M) over dot (a)/(M) over dot (w)) Assuming nonspherical cloud collapse, we find that relatively strong winds can carve out wide, conical outflow cavities and that relatively weak winds can be strongly collimated into jetlike structures. If the winds become weak enough, they can be cut off entirely by the infalling environment. We identify discrepancies between results from standard snowplow models and those presented here that have important implications for molecular outflows. We also present mass versus velocity curves for comparison with observations. C1 Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Delamarter, G (reprint author), Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. NR 46 TC 35 Z9 35 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 FEB 20 PY 2000 VL 530 IS 2 BP 923 EP 938 DI 10.1086/308389 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500030 ER PT J AU Revnivtsev, MG Borozdin, KN Priedhorsky, WC Vikhlinin, A AF Revnivtsev, MG Borozdin, KN Priedhorsky, WC Vikhlinin, A TI Rossi X-Ray Timing Explorer observations of an outburst of recurrent X-ray nova GS 1354-644 SO ASTROPHYSICAL JOURNAL LA English DT Article DE novae, cataclysmic variables; stars : individual (GS 1354-644); X-rays : stars ID BLACK-HOLE CANDIDATES; RXTE OBSERVATION; HIGH STATE; RADIATION; COMPTONIZATION; VARIABILITY; CYGNUS-X-1; MODEL; REFLECTION; 4U-1608-52 AB We present the results of Rossi X-Ray Timing Explorer (RXTE) observations of GS 1354-644 during a modest outburst in 1997-1998. The source is one of a handful of black hole X-ray transients that are confirmed to be recurrent in X-rays. A 1987 outburst of the same source observed by Ginga was much brighter and showed a high/soft spectral state. In contrast, the 1997-1998 outburst showed a low/hard spectral state. Both states are typical of black hole binaries. The RXTE All-Sky Monitor observed an outburst duration of 150-200 days. PCA and HEXTE observations covered similar to 70 days near the maximum of the light curve and during the flux decline. Throughout the observations, the spectrum can be approximated by Compton upscattering of soft photons by energetic electrons. The hot electron cloud has a temperature kT similar to 30 keV and optical depth tau similar to 4-5. To fit the data well, an additional iron fluorescent line and reflection component are required, which indicates the presence of optically thick cool material, most probably in the outer part of the accretion disk. Dramatic fast variability was observed and has been analyzed in the context of a shot noise model. The spectrum appeared to be softest at the peaks of the shot noise variability. The shape of the power spectrum was typical for black hole systems in a low/hard state. We note a qualitative difference in the shape of the dependence of fractional variability on energy when we compare systems with black holes and with neutron stars. Since it is difficult to discriminate these systems on spectral grounds, at least in their low/hard states, this new difference might be important. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Revnivtsev, MG (reprint author), Russian Acad Sci, Inst Space Res, 84-32 Profsojuznaya Str,GSP 7, Moscow 117810, Russia. OI Priedhorsky, William/0000-0003-0295-9138 NR 57 TC 20 Z9 21 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP 955 EP 965 DI 10.1086/308386 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500033 ER PT J AU Frazin, RA AF Frazin, RA TI Tomography of the solar corona. I. A robust, regularized, positive estimation method SO ASTROPHYSICAL JOURNAL LA English DT Article DE methods : statistical; solar wind; Sun : corona ID LINEAR INVERSE PROBLEMS; GENERALIZED CROSS-VALIDATION; IMAGE-RESTORATION; DISCRETE-DATA; RECONSTRUCTION; EMISSION; CHOICE; NOISY; PARAMETERS AB A general method for the reconstruction of emissivity structures in the solar corona from projection data is presented. The method creates a robust, regularized, positive estimate (RRPE) of the coronal emissivity distribution. The problem of reconstructing the three-dimensional emissivity from a time series of coronagraph images is considered in detail. The discussion is set in the framework of the robust solution of underdetermined, linear systems of equations. In two-dimensional numerical experiments, the RRPE method is compared to the multiplicative algebraic reconstruction technique (MART), and the superiority of RRPE is demonstrated. The most important and restrictive assumptions upon which the methodology is based are (1) that the structure of the corona does not vary with time and (2) that there are enough coronagraph images to resolve the longitudinal structures of the corona. The consequences of these assumptions are not addressed here but will be studied in future work. The three-dimensional reconstruction of the coronal electron density from a time series of actual coronagraph images is deferred to a subsequent paper in this series. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Frazin, Richard/J-2625-2012 NR 67 TC 49 Z9 49 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 FEB 20 PY 2000 VL 530 IS 2 BP 1026 EP 1035 DI 10.1086/308412 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500039 ER PT J AU Brinkman, AC Gunsing, CJT Kaastra, JS van der Meer, RLJ Mewe, R Paerels, F Raassen, AJJ van Rooijen, JJ Brauninger, H Burkert, W Burwitz, V Hartner, G Predehl, P Ness, JU Schmitt, JHMM Drake, JJ Johnson, O Juda, M Kashyap, V Murray, SS Pease, D Ratzlaff, P Wargelin, BJ AF Brinkman, AC Gunsing, CJT Kaastra, JS van der Meer, RLJ Mewe, R Paerels, F Raassen, AJJ van Rooijen, JJ Brauninger, H Burkert, W Burwitz, V Hartner, G Predehl, P Ness, JU Schmitt, JHMM Drake, JJ Johnson, O Juda, M Kashyap, V Murray, SS Pease, D Ratzlaff, P Wargelin, BJ TI First light measurements of Capella with the low-energy transmission grating spectrometer aboard the Chandra X-Ray Observatory SO ASTROPHYSICAL JOURNAL LA English DT Article DE instrumentation : spectrographs; line : identification; plasmas; stars : coronae; stars : individual (Capella); X-rays : stars ID STELLAR CORONAE; FE-XVII; LINE RATIOS; AXAF; SPECTROSCOPY; CALIBRATION; RESOLUTION; EMISSION; SPECTRUM; FLARE AB We present the first X-ray spectrum obtained by the Low-Energy Transmission Grating Spectrometer (LETGS) aboard the Chandra X-Ray Observatory. The spectrum is of Capella and covers a wavelength range of 5-175 Angstrom (2.5-0.07 keV). The measured wavelength resolution, which is in good agreement with ground calibration, is Delta lambda similar or equal to 0.06 Angstrom (FWHM). Although in-flight calibration of the LETGS is in progress, the high spectral resolution and unique wavelength coverage of the LETGS are well demonstrated by the results from Capella, a coronal source rich in spectral emission lines. While the primary purpose of this Letter is to demonstrate the spectroscopic potential of the LETGS, we also briefly present some preliminary astrophysical results. We discuss plasma parameters derived from line ratios in narrow spectral bands, such as the electron density diagnostics of the He-like triplets of carbon, nitrogen, and oxygen, as well as resonance scattering of the strong Fe XVII line at 15.014 Angstrom. C1 Space Res Org Netherlands, NL-3584 CA Utrecht, Netherlands. Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Univ Hamburg, D-21029 Hamburg, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. RP Brinkman, AC (reprint author), Space Res Org Netherlands, Sorbonnelaan 2, NL-3584 CA Utrecht, Netherlands. NR 26 TC 107 Z9 110 U1 3 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP L111 EP L114 DI 10.1086/312504 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BX UT WOS:000086062600015 ER PT J AU Harris, DE Nulsen, PEJ Ponman, TJ Bautz, M Cameron, RA David, LP Donnelly, RH Forman, WR Grego, L Hardcastle, MJ Henry, JP Jones, C Leahy, JP Markevitch, M Martel, AR McNamara, BR Mazzotta, P Tucker, W Virani, SN Vrtilek, J AF Harris, DE Nulsen, PEJ Ponman, TJ Bautz, M Cameron, RA David, LP Donnelly, RH Forman, WR Grego, L Hardcastle, MJ Henry, JP Jones, C Leahy, JP Markevitch, M Martel, AR McNamara, BR Mazzotta, P Tucker, W Virani, SN Vrtilek, J TI Chandra X-ray detection of the radio hot spots of 3C 295 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (3C 295); magnetic fields; radiation mechanisms : nonthermal ID CYGNUS-A; EMISSION; GALAXY; JET AB An observation of the radio galaxy 3C 295 during the calibration phase of the Chandra X-Ray Observatory reveals X-ray emission from the core of the galaxy, from each of the two prominent radio hot spots, and from the previously known cluster gas. We discuss the possible emission processes for the hot spots and argue that a synchrotron self-Compton (SSC) model is preferred for most or all of the observed X-ray emission. SSC models with near-equipartition fields thus explain the X-ray emission from the hot spots in the two highest surface brightness FR II radio galaxies, Cygnus A and 3C 295. This lends weight to the assumption of equipartition and suggests that relativistic protons do not dominate the particle energy density. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Wollongong, Dept Engn Phys, Wollongong, NSW 2522, Australia. Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. MIT, Ctr Space Res, Cambridge, MA 02139 USA. Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Univ Manchester, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Harris, DE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Hardcastle, Martin/E-2264-2012; Mazzotta, Pasquale/B-1225-2016 OI Hardcastle, Martin/0000-0003-4223-1117; Mazzotta, Pasquale/0000-0002-5411-1748 NR 10 TC 54 Z9 54 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP L81 EP L84 DI 10.1086/312503 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BX UT WOS:000086062600008 ER PT J AU Myers, PC AF Myers, PC TI Growth of an initial mass function cluster in a turbulent dense core SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; stars : formation; stars : luminosity function, mass function; turbulence ID STAR-FORMATION; MOLECULAR CLOUDS; ISOTHERMAL SPHERE; COLLAPSE; FRAGMENTATION AB A simple model of condensation growth and collapse in a turbulent dense core yields a distribution of stellar masses that matches the main features of the stellar initial mass function (IMF). In this model, stars in the "flat" and "power-law" parts of the IMF come from condensations with negligible and substantial growth, respectively. The mass accretion rate of a condensation is proportional to its mass, and the probability of stopping accretion is equal in every time interval, so the growth is exponential and its duration follows a Poisson distribution. For mass growth e-folding time tau(grow) and mean duration tau(stop), the stellar mass m has a probability density per logarithmic mass interval of similar to m(-x), where x tau(grow)/tau(stop). This power-law relation matches the IMF when tau(grow) approximate to tau(stop), as is expected if each of these times is set by the same properties of the surrounding core gas. We specify exponential growth arising from Bondi accretion onto a stationary Bonnor-Ebert sphere, in a core heated and stirred by associated stars. This growth is exponential, unlike the Bondi accretion onto a star, but "slow," with tau(grow) greater than the free-fall time of the condensation by a factor of similar to 4. We specify random stopping as due to sudden turbulent compression, which causes the condensation to collapse and stop accreting. For these mechanisms, a core with a density of 10(4) cm(-3) grows a cluster of similar to 100 IMF-following stars with a mass range of 1-25 M. in 1.4 Myr, in accord with the masses and ages of embedded clusters. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Myers, PC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 42, Cambridge, MA 02138 USA. EM pmyers@cfa.harvard.edu NR 45 TC 24 Z9 24 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 FEB 20 PY 2000 VL 530 IS 2 BP L119 EP L122 DI 10.1086/312495 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BX UT WOS:000086062600017 ER PT J AU Nicastro, F AF Nicastro, F TI Broad emission line regions in active galactic nuclei: The link with the accretion power SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; galaxies : active; quasars : emission lines ID RADIO GALAXIES; BINARY-SYSTEMS; BLACK-HOLES AB We present a model that relates the width of the broad emission lines of active galactic nuclei (AGNs) to the Keplerian velocity of an accretion disk at a critical distance from the central black hole. This critical distance falls in a region bounded on the inward side by the transition radius between the radiation pressure- and the gas pressure-dominated region of the accretion disk and on the outward side by the maximum radius below which a stabilizing, radially accreting and vertically outflowing corona exists. We show that in the framework of this picture, the observed range of H beta FWHMs from broad-line to narrow-line type 1 AGNs is well reproduced as a function of the accretion rate. This interval of velocities is the only permitted range and goes from similar to 20,000 km s(-1) for sub-Eddington accretion rates to similar to 1000 km s(-1) fur Eddington accretion rates. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Nicastro, F (reprint author), Osservatorio Astron Roma, Monteporzio Catone, RM, Italy. NR 20 TC 132 Z9 133 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP L65 EP L68 DI 10.1086/312491 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BX UT WOS:000086062600004 ER PT J AU Golub, L Harra, L Priest, ER Uchida, Y Pudritz, RE Lynden-Bell, D AF Golub, L Harra, L Priest, ER Uchida, Y Pudritz, RE Lynden-Bell, D TI Solar activity studies through coronal X-ray observations - Discussion SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Editorial Material C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ St Andrews, St Andrews KY16 9AJ, Fife, Scotland. Univ Tokyo, Tokyo, Japan. Queens Univ, Belfast, Antrim, North Ireland. RP Golub, L (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ROYAL SOC LONDON PI LONDON PA 6 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X J9 PHILOS T ROY SOC A JI Philos. Trans. R. Soc. Lond. Ser. A-Math. Phys. Eng. Sci. PD FEB 15 PY 2000 VL 358 IS 1767 BP 654 EP 655 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 290HE UT WOS:000085670200003 ER PT J AU Gough, D Parnell, CE Golub, L Hide, R Siebenburgen, RV Priest, ER Uchida, Y Kerr, R Galsgaard, K AF Gough, D Parnell, CE Golub, L Hide, R Siebenburgen, RV Priest, ER Uchida, Y Kerr, R Galsgaard, K TI Magnetic reconnection and some solar applications - Discussion SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Editorial Material C1 Univ Cambridge, Cambridge CB2 1TN, England. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Sheffield, Sheffield S10 2TN, S Yorkshire, England. Univ St Andrews, St Andrews KY16 9AJ, Fife, Scotland. Univ Tokyo, Tokyo, Japan. NCAR, Boulder, CO USA. RP Gough, D (reprint author), Univ Cambridge, Cambridge CB2 1TN, England. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ROYAL SOC LONDON PI LONDON PA 6 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X J9 PHILOS T ROY SOC A JI Philos. Trans. R. Soc. Lond. Ser. A-Math. Phys. Eng. Sci. PD FEB 15 PY 2000 VL 358 IS 1767 BP 686 EP 688 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 290HE UT WOS:000085670200007 ER PT J AU Moran, JM AF Moran, JM TI High-resolution maser studies of galactic nuclei SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article DE masers; black holes; magnetic fields ID ASTROPHYSICAL WATER MASERS; SPIRAL GALAXY NGC-4258; STRONG MAGNETIC-FIELDS; ACCRETION DISKS; MOLECULAR DISK; BLACK-HOLES; H2O; EMISSION; DISCOVERY; JET AB Water vapour masers are proving to be remarkably useful probes of the neutral accretion discs surrounding black holes at radii of a few tenths of a parsec. This paper describes the observational results on NGC 4258, including measurements of the magnetic field (less than 300 mG), the accelerations of the high-velocity features (-0.8 to 0.4 km s(-1) yr(-1)), and the distance (7.2 +/- 0.5 Mpc). The status of measurements of other masers with resolved structure is also described. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Moran, JM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 42, Cambridge, MA 02138 USA. NR 39 TC 3 Z9 3 U1 0 U2 0 PU ROYAL SOC LONDON PI LONDON PA 6 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X J9 PHILOS T ROY SOC A JI Philos. Trans. R. Soc. Lond. Ser. A-Math. Phys. Eng. Sci. PD FEB 15 PY 2000 VL 358 IS 1767 BP 797 EP 810 DI 10.1098/rsta.2000.0559 PG 14 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 290HE UT WOS:000085670200020 ER PT J AU Lukin, MD Imamoglu, A AF Lukin, MD Imamoglu, A TI Nonlinear optics and quantum entanglement of ultraslow single photons SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; HARTREE APPROXIMATION; INTERACTING PHOTONS; INTERFERENCE; MEDIA AB Two light pulses propagating with slow group velocities in a coherently prepared atomic gas exhibit dissipation-free nonlinear coupling of an unprecedented strength. This enables a single-photon pulse to coherently control or manipulate the quantum state of the other. Processes of this kind result in generation of entangled states elf radiation field and open up new prospectives for quantum information processing. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Univ Calif Santa Barbara, Dept Elect & Comp Engn, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. RP Lukin, MD (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. NR 28 TC 469 Z9 481 U1 3 U2 30 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 FEB 14 PY 2000 VL 84 IS 7 BP 1419 EP 1422 DI 10.1103/PhysRevLett.84.1419 PG 4 WC Physics, Multidisciplinary SC Physics GA 283GB UT WOS:000085267100015 ER PT J AU Telesco, CM Fisher, RS Pina, RK Knacke, RF Dermott, SF Wyatt, MC Grogan, K Holmes, EK Ghez, AM Prato, L Hartmann, LW Jayawardhana, R AF Telesco, CM Fisher, RS Pina, RK Knacke, RF Dermott, SF Wyatt, MC Grogan, K Holmes, EK Ghez, AM Prato, L Hartmann, LW Jayawardhana, R TI Deep 10 and 18 micron imaging of the HR 4796A circumstellar disk: Transient dust particles and tentative evidence for a brightness asymmetry SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; infrared : stars; stars : individual (HR 4796A) ID BETA-PICTORIS; DEBRIS; HR-4796; SYSTEM; PLANET AB We present new 10.8 and 18.2 mu m images of HR 4796A, a young AO V star that was recently discovered to have a spectacular, nearly edge-on, circumstellar disk prominent at similar to 20 mu m (Jayawardhana and coworkers; Koerner and coworkers). These new images, obtained with OSCIR (the University of Florida Observatory Spectrometer/Camera for the Infrared) at Keck. II, show that the disk's size at 10 mu m is comparable to its size at 18 mu m. Therefore, the 18 mu m-emitting dust may also emit some, or ail, of the 10 mu m radiation. Using these multiwavelength images, we determine a "characteristic" diameter of 2-3 mu m for the mid-infrared-emitting dust particles if they are spherical and composed of astronomical silicates. Particles this small, are expected to be blown out of the system by radiation pressure in a few hundred years, and therefore these particles are unlikely to be primordial. Rather, as inferred in a companion paper (Wyatt and coworkers), they are probably products of collisions that dominate both the creation and the destruction of dust in the HR 4796A disk. Dynamical modeling of the disk, the details of which are presented in the companion paper, indicates that the disk surface density is relatively sharply peaked near 70 AU, which agrees with the mean annular radius deduced by Schneider and coworkers from their NICMOS images. Interior to 70 AU, the model density drops steeply by a factor of 2 between 70 and 60 AU, falling to zero by 45 AU, which corresponds to the edge of the previously discovered central hole; in the context of the dynamical models, this "soft" edge for the central hole occurs because the dust particle orbits are noncircular. The optical depth of mid-infrared-emitting dust in the hole is similar to 3% of the optical depth in the disk, and the hole is therefore relatively very empty. We present evidence (similar to 1.8 sigma significance) for a brightness asymmetry that may result from the presence of the hole and the gravitational perturbation of the disk particle orbits by the low-mass stellar companion or a planet. This "pericenter glow," which must still be confirmed, results from a very small (a few AU) shift of the disk's center of symmetry relative to the central star HR 7496A; one side of the inner boundary of the annulus is shifted toward HR 4796A, thereby becoming warmer and more infrared-emitting. The possible detection of pericenter glow implies that the detection of even complex dynamical effects of planets on disks is within reach. C1 Univ Florida, Dept Astron, Gainesville, FL 32611 USA. Penn State Univ, Sch Sci, Erie, PA 16563 USA. Univ Calif Los Angeles, Dept Astron, Los Angeles, CA 90095 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Telesco, CM (reprint author), Univ Florida, Dept Astron, Gainesville, FL 32611 USA. NR 28 TC 98 Z9 98 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 10 PY 2000 VL 530 IS 1 BP 329 EP 341 DI 10.1086/308332 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290YC UT WOS:000085704600028 ER PT J AU Apponi, AJ McCarthy, MC Gottlieb, CA Thaddeus, P AF Apponi, AJ McCarthy, MC Gottlieb, CA Thaddeus, P TI Laboratory detection of four new cumulene carbenes: H2C7, H2C8, H2C9, and D2C10 SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : molecules; line : identification; molecular data; molecular processes; radio lines : ISM; stars : individual(IRC+10216) ID CARBON-CHAIN CARBENE; ASTRONOMICAL DETECTION; ROTATIONAL SPECTRA; PROPADIENYLIDENE; H2CCCC; TMC-1 AB Four new cumulene carbenes, H2C7, H2C8, H2C9, and D2C10, were detected in the laboratory by Fourier transform microwave spectroscopy. Like the shorter cumulenes in this series, all four were found to have singlet electronic ground states and linear carbon chain backbones. Rotational and centrifugal distortion constants were determined to high accuracy for each molecule, and the entire radio spectrum of each can be calculated to better than 0.3 km s(-1) in equivalent radial velocity up to 100 GHz. Upper limits of the H2C7, H2C8, and H2C9 column densities have been estimated for the circumstellar shell of the evolved carbon star IRC +/- 10216. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP Apponi, AJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI McCarthy, Michael/0000-0001-9142-0008 NR 20 TC 20 Z9 20 U1 1 U2 9 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 10 PY 2000 VL 530 IS 1 BP 357 EP 361 DI 10.1086/308353 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290YC UT WOS:000085704600031 ER PT J AU Brickhouse, NS Dupree, AK Edgar, RJ Liedahl, DA Drake, SA White, NE Singh, KP AF Brickhouse, NS Dupree, AK Edgar, RJ Liedahl, DA Drake, SA White, NE Singh, KP TI Coronal structure and abundances of Capella from simultaneous EUVE and ASCA spectroscopy SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : spectroscopic; stars : abundances; stars : coronae; stars : individual (Capella); ultraviolet : stars; X-rays : stars ID X-RAY-EMISSION; CANUM-VENATICORUM BINARIES; EXTREME-ULTRAVIOLET OBSERVATIONS; CHROMOSPHERICALLY ACTIVE STARS; LOCAL INTERSTELLAR-MEDIUM; K-TYPE STARS; LINE EMISSION; COOL STARS; AR-LACERTAE; OUTER ATMOSPHERES AB We report analysis of the simultaneous 1996 March EUVE and ASCA observations of the spectroscopic binary Capella. The EUVE spectrum is dominated by lines of highly ionized Fe, requiring a continuous emission-measure distribution over a wide range of temperatures. The ASCA spectrum shows He-like line emission features of S, Si, and Mg, as well as unresolved L-shell emission lines of Fe and Ni and H-like and He-like Ne lines. The flux in these line features cannot be determined independently from the continuum flux. The ASCA spectrum is relatively soft, with few counts above 4 keV. The emission-measure distribution determined by Line-Based Analysis of the EUV Fe line intensities is well constrained from T(e)similar to 6 x 10(5) to 2 x 10(7) K, but it is not constrained above this range since Fe XXIV is the highest temperature line observed with EUVE. Since repeated observations of Capella by EUVE have shown that emission-line intensities of the hottest EUV-emitting material (Fe XXI to XXIV) vary by factors up to 4, the ASCA spectrum is important for extending the temperature coverage. Thus, the high-energy cut-off of the ASCA spectrum provides a constraint on the highest temperature emission measures. In principle, elemental abundances are determined from global fits to the ASCA spectrum; however, no well-fitting model has been found for the high signal-to-noise ASCA performance verification spectrum of Capella (1993 September 2). The newer ASCA spectrum of Capella (1996 March 3-4) shows a similar pattern of fitting difficulties. Using the EUVE measurements (1996 March 3-7) to constrain models, we have conducted sensitivity studies of the atomic data, source physics, and instrument calibration. The plasma spectral emission models (Raymond-Smith, MEKAL, SPEX) around 1.2 keV appear to have flux deficits relative to the observed ASCA count spectrum. New atomic models by Liedahl and Brickhouse, calculated with the HULLAC code, provide a set of lines-missing from the existing plasma codes-to fill in this flux deficit. Incorporating these additional lines dramatically improves the spectral model fits to the data, allowing reliable determination of elemental abundances. The successful application of the new atomic models to the Capella problem can have widespread implications, affecting spectral models of galaxies, cluster cooling flows, and supernova remnants, as well as other stellar coronae. Analysis with the new atomic models of the simultaneous ASCA and EUVE data confirms the previous EUVE results that the continuous emission-measure distribution of Capella has a strong enhancement at T(e)similar to 6 x 10(6) K. While a two-temperature model actually provides a better fit to the ASCA spectrum than the EUVE-derived continuous model, the EUVE data are not well fitted with only two temperatures. We find that the abundances of Mg, Si, S, and Fe are consistent with solar photospheric values, while Ne appears to be underabundant by a factor of similar to 3 to 4. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Tata Inst Fundamental Res, Dept Astron & Astrophys, Bombay 400005, Maharashtra, India. RP Brickhouse, NS (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. RI White, Nicholas/B-6428-2012; OI White, Nicholas/0000-0003-3853-3462; Brickhouse, Nancy/0000-0002-8704-4473 NR 74 TC 85 Z9 86 U1 0 U2 6 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 10 PY 2000 VL 530 IS 1 BP 387 EP 402 DI 10.1086/308350 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290YC UT WOS:000085704600034 ER PT J AU Wagner, WL Harris, EM AF Wagner, WL Harris, EM TI A unique Hawaiian Schiedea (Caryophyllaceae : Alsinoideae) with only five fertile stamens SO AMERICAN JOURNAL OF BOTANY LA English DT Article DE caryophyllaceae; endangered species; floral development; Hawaiian Islands; scanning electron microscopy; Schiedea ID EVOLUTION AB The floral organogenesis and subsequent ontogenies of the Hawaiian endemic species Schiedea pubescens from Maul, Moloka'i, and Lana'i, and the Wai'anae Mountains, O'ahu, populations previously considered to be varietally distinct, were examined using the scanning electron microscope (SEM). The O'ahu population consistently produced only five fertile stamens, those of the inner whorl. The five stamens of the alterniscpalous or outer whorl abort prior to microsporogenesis and fail to elongate. Additional vegetative differences between the two taxa, combined with the floral morphology characters, merit the description of the O'ahu population as a new species, S. pentandra, described herein. C1 Natl Museum Nat Hist, Dept Bot, Smithsonian Inst, Washington, DC 20560 USA. Ohio State Univ, Herbarium, Museum Biol Divers, Columbus, OH 43212 USA. RP Wagner, WL (reprint author), Natl Museum Nat Hist, Dept Bot, Smithsonian Inst, MRC-166, Washington, DC 20560 USA. NR 22 TC 5 Z9 5 U1 0 U2 0 PU BOTANICAL SOC AMER INC PI COLUMBUS PA OHIO STATE UNIV-DEPT BOTANY 1735 NEIL AVE, COLUMBUS, OH 43210 USA SN 0002-9122 J9 AM J BOT JI Am. J. Bot. PD FEB PY 2000 VL 87 IS 2 BP 153 EP 160 DI 10.2307/2656901 PG 8 WC Plant Sciences SC Plant Sciences GA 285NM UT WOS:000085395200001 PM 10675301 ER PT J AU Schwartz, GT AF Schwartz, GT TI Taxonomic and functional aspects of the patterning of enamel thickness distribution in extant large-bodied hominoids SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Review DE enamel thickness; maxillary molars; modern humans; great apes; mastication; tooth function; diet; enamel development ID HUMAN MAXILLARY MOLARS; PLIOPLEISTOCENE HOMINIDS; PAN-TROGLODYTES; STRESS-ANALYSIS; BITE FORCES; PRIMATES; TOOTH; RATIOS; TEETH; EVOLUTION AB One of the few uncontested viewpoints in studies of enamel thickness is that the molars of the African apes, Pan and Gorilla, possess "thin" enamel, while Pongo and modern humans possess varying degrees of "thick" enamel, even when interspecific differences in overall body or tooth size are taken into account. Such studies focus primarily on estimates of the total volume of enamel relative to tooth size (i.e., "relative" enamel thickness), as this is thought to bear directly on questions concerning dietary proclivities and phylogenetic relationships. Only recently have studies shifted focus to examining differences in the distribution of enamel across the tooth crown, i.e., the patterning of enamel thickness, as this may contribute to more refined models of tooth function and dietary adaptations in extant hominoids. Additionally, this feature has been suggested to be a reliable indicator of taxonomic affinity in early hominins, though no study has specifically addressed whether species-specific patterns exist among known phena. The aims of this paper were to test more explicitly whether enamel thickness patterning provides valuable taxonomic, functional, and/or phylogenetic information for maxillary molars of large-bodied extant hominoids. A series of seven linear enamel thickness measurements was recorded in the plane of the mesial cusps in cross sections of a total of 62 maxillary molars of P. troglodytes, G. gorilla, P. pygmaeus, and H. sapiens to estimate the patterning of enamel thickness distribution. Results from a discriminant function analysis reveal that, overall, this trait reclassifies extant hominoid maxillary molars with 90% accuracy: 100% of extant Homo, 75.0% of Pongo, 83.3% of Pan, and 66.7% of Gorilla ale reclassified correctly, indicating that this feature possesses a strong taxonomic signal. Furthermore, differences in the structure of the enamel cap are evident among hominoids: modern humans differ from Pongo in possessing proportionally thicker enamel in areas of the crown associated with shearing activity; Pan molars are better designed than those of Gorilla for generating a greater component of crushing/grinding loads. Thus, African ape molars are structurally dissimilar, even though they are both considered to belong to a morphologically homogeneous "thin-enameled" group. Simple developmental mechanisms can be invoked to explain the sometimes subtle differences in the achievement of adult morphology. For instance, human and orangutan molar cusps possess a similar degree of enamel thickness, but the possibility exists that despite similarities in morphology, each species follows a different sequence of secretory activity of enamel to achieve the final, albeit similar, degree of enamel thickness. Such a finding would suggest that the shared possession of "thick" or "thin" enamel among species may be phylogenetically uninformative, as it would not represent a developmental synapomorphy. (C) 2000 Wiley-Liss, Inc. C1 George Washington Univ, Dept Anthropol, Washington, DC 20052 USA. Smithsonian Inst, Natl Museum Nat Hist, Human Origins Program, Washington, DC 20560 USA. RP Schwartz, GT (reprint author), George Washington Univ, Dept Anthropol, 2110 G St NW, Washington, DC 20052 USA. NR 127 TC 95 Z9 97 U1 2 U2 9 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PD FEB PY 2000 VL 111 IS 2 BP 221 EP 244 DI 10.1002/(SICI)1096-8644(200002)111:2<221::AID-AJPA8>3.0.CO;2-G PG 24 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 280ZJ UT WOS:000085133400008 PM 10640949 ER PT J AU Piper, WH Tischler, KB Klich, M AF Piper, WH Tischler, KB Klich, M TI Territory acquisition in loons: the importance of take-over SO ANIMAL BEHAVIOUR LA English DT Article ID RED-WINGED BLACKBIRDS; MALE SONG SPARROWS; COMMON LOON; SITE FIDELITY; GAVIA-IMMER; NEST SITES; FLOATERS; BIRDS; BEHAVIOR; COMPETITION AB We examined patterns of territory acquisition and reconnaissance in common loons, Gavia immer, from northern Wisconsin. Among all territory acquisitions, 41.5% occurred through passive occupation of territories left vacant after the death or desertion of a previous resident, 17% constituted founding of new territories and the remaining 41.5% came about through, take-over: either usurpation of defended territories or appropriation of territories before the seasonal return of previous owners. Take-overs occurred in both sexes, but individuals acted alone, never in pairs. Displaced breeders usually took refuge on undefended lakes near their former territories; about half of these loons later regained former territories through passive occupation or took possession of new territories elsewhere. As predicted by the reconnaissance hypothesis, usurpations occurred most often in territories that had produced chicks during the previous 12 months, suggesting that loons use the presence or absence of chicks as a cue for territorial usurpation. Large individuals of both sexes held onto territories longer than small individuals, an indication that body size might be correlated with fighting ability. In terms of life history, loons appear to locate good territories through reconnaissance, usurp them in a subsequent year and recover from displacements by reclaiming their original territories or new ones. (C) 2000 The Association for the Study of Animal Behaviour. C1 Smithsonian Inst, Mol Genet Lab, Washington, DC 20560 USA. George Mason Univ, Dept Biol, Fairfax, VA 22030 USA. RP Piper, WH (reprint author), Chapman Univ, Dept Biol Sci, 1 Univ Dr, Orange, CA 92866 USA. RI Piper, Walter/B-7908-2009 NR 53 TC 53 Z9 53 U1 0 U2 16 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0003-3472 J9 ANIM BEHAV JI Anim. Behav. PD FEB PY 2000 VL 59 BP 385 EP 394 DI 10.1006/anbe.1999.1295 PN 2 PG 10 WC Behavioral Sciences; Zoology SC Behavioral Sciences; Zoology GA 293MM UT WOS:000085855900015 ER PT J AU Rappole, JH King, DI Leimgruber, P AF Rappole, JH King, DI Leimgruber, P TI Winter habitat and distribution of the endangered golden-cheeked warbler (Dendroica chrysoparia) SO ANIMAL CONSERVATION LA English DT Article ID DEFORESTATION; MEXICO; RATES AB The golden-cheeked warbler (Dendroica chrysoparia) is an endangered Neotropical migrant that breeds in oak (Quercus)/juniper (Juniperus) habitat of the Edwards Plateau in central Texas. Recently work has been done on the factors affecting breeding populations of this species, but little is known about winter habitat use or distribution. We used extensive field surveys in Honduras and Guatemala to obtain locational information, which was used with topographical and remote sensing data, to identify and calculate the amount of suitable habitat available, and to map the species' distribution in the region. Most individuals were found in pine-oak from 1100-2400 m ((x) over bar = 1651 (+/- 246) m) in elevation, a habitat type that occupied 29.8% of the total land area above 914 m in the region investigated. Based on this information and existing locational data from the literature, we present a map of the winter range for the golden-cheeked warbler. Threats to the species during this period of the life cycle include logging, burning and clearing for pasture and agriculture. C1 Smithsonian Conservat & Res ctr, Front Royal, VA 22630 USA. Univ Massachusetts, Dept Forestry & Wildlife Management, Holdsworth Nat Resources Ctr 203, Amherst, MA 01003 USA. RP Rappole, JH (reprint author), Smithsonian Conservat & Res ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. RI Leimgruber, Peter/O-1304-2015 OI Leimgruber, Peter/0000-0002-3682-0153 NR 27 TC 3 Z9 3 U1 0 U2 10 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 1367-9430 J9 ANIM CONSERV JI Anim. Conserv. PD FEB PY 2000 VL 3 BP 45 EP 59 DI 10.1111/j.1469-1795.2000.tb00086.x PN 1 PG 15 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 344KE UT WOS:000088757100006 ER PT J AU Willett, F Sayre, EV AF Willett, F Sayre, EV TI The elemental composition of Benin memorial heads SO ARCHAEOMETRY LA English DT Article DE Nigeria; Benin City; Udo; medieval; modern; atomic absorption; elemental analysis; multivariate statistical analysis; optical emission spectroscopy; proton-induced x-ray emission spectroscopy; wet chemical analysis; x-ray fluorescence; bracelets; figures; memorial heads; brass; bronze; copper alloy; composition; dating AB Among the Nigerian cast copper-alloy artefacts, the chronology of the Benin memorial heads has been the most fully worked out. Therefore, a study focused upon their elemental compositions is particularly likely to be interpretable in terms of development of the alloys used in their making. The elemental analyses, both published and unpublished, of 66 Benin heads, supplemented with seven analyses of some artefacts excavated from a well-dated, very early Benin site, have been collected, analysed statistically and compared to the elemental analyses of 11 heads and figures from Udo. All but a very few of the Benin heads and artefacts separate into five compositional groups, indicating a chronological sequence of different alloying traditions. All but one of the Udo objects fall into a distinctly separate compositional group, together with two Medicine heads. The compositional groups correlated remarkably well with the stylistic types proposed by Dark. C1 Univ Glasgow, Hunterian Museum, Glasgow G12 8QQ, Lanark, Scotland. Smithsonian Inst, Smithsonian Ctr Materials Res, Washington, DC 20560 USA. RP Willett, F (reprint author), Univ Glasgow, Hunterian Museum, Glasgow G12 8QQ, Lanark, Scotland. NR 47 TC 2 Z9 2 U1 0 U2 0 PU OXFORD UNIV PI OXFORD PA RES LAB ARCHAEOL HIST ART 6 KEBLE RD, OXFORD OX1 3QJ, ENGLAND SN 0003-813X J9 ARCHAEOMETRY JI Archaeometry PD FEB PY 2000 VL 42 BP 159 EP 188 DI 10.1111/j.1475-4754.2000.tb00874.x PN 1 PG 30 WC Archaeology; Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Geosciences, Multidisciplinary SC Archaeology; Chemistry; Geology GA 289QL UT WOS:000085633400013 ER PT J AU Da Costa, GS Armandroff, TE Caldwell, N Seitzer, P AF Da Costa, GS Armandroff, TE Caldwell, N Seitzer, P TI The dwarf spheroidal companions to M31: WFPC2 observations of Andromeda II SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : abundances; galaxies : dwarf; galaxies : individual (Andromeda I, Andromeda II); galaxies : photometry; galaxies : stellar content; local group ID COLOR-MAGNITUDE DIAGRAMS; HUBBLE-SPACE-TELESCOPE; ENHANCED GALACTIC WINDS; LOCAL GROUP GALAXIES; GLOBULAR-CLUSTERS; GIANT BRANCH; RESOLVED GALAXIES; SPIRAL GALAXIES; BRIGHT STARS; CALIBRATION AB The Hubble Space Telescope WFPC2 camera has been used to image Andromeda II, a dwarf spheroidal (dSph) companion to M31. The resulting color-magnitude (c-m) diagrams reveal the morphology of the horizontal branch (HB) in this dwarf galaxy. We find that like Andromeda I, and like most of the Galactic dSph companions, the HE morphology of And II is predominantly red. Unlike And I, however, there is no evidence for a radial gradient in HE morphology in the And II data. Based on a comparison with a combination of standard Galactic globular cluster c-m diagrams scaled to reproduce the And II mean abundance and abundance dispersion, we interpret the observed HE morphology of And II as indicating that at least 50% of the total stellar population is younger than the age of the globular clusters. This inference is strengthened by the small number of confirmed upper-AGE carbon stars in And II. The relatively faint luminosities (M-bol approximate to -4.1) of these stars, however, suggest an age or ages nearer 6-9 Gyr, rather than 1-3 Gyr, for this population. On the other hand, the existence of blue HE and RR Lyrae variable stars in And II argues for the existence of an additional old (age > 10 Gyr) population in this dSph. Thus, And II has had an extended epoch of star formation like many of the Galactic dSphs. The mean magnitude of the blue HE in And II suggests (m-M)(0) = 24.17 +/- 0.06 and that And II is 125 +/- 60 kpc closer than M31 along the line of sight. This confirms the association of And II with M31, rather than with M33 to which And II lies closer on the sky. The true distance of And II from the center of M31 is between similar to 160 and similar to 230 kpc, comparable to the Galactocentric distances of Fornax and of the Leo dSphs. With the current samples of dSph companions, the size of the Galaxy's and M31's dSph satellite systems are comparable, with outer radii of order 250 kpc. The And II red giant branch colors yield a mean abundance of <[Fe/H]> = -1.49 +/- 0.11 and a surprisingly large internal abundance spread, which can be characterised by sigma(int)([Fe/H]) approximate to 0.36 dex. Both these values are in good agreement with the recent ground-based spectroscopic study of Cati et al. The And II abundance dispersion found here is considerably larger than that derived for And I from an identical analysis of similar data (sigma(int)([Fe/H])= 0.21 dex). Thus, despite having very similar luminosities and mean metal abundances, these two M31 dSph companions have clearly had different chemical evolution histories. We find that we cannot model the abundance distribution in And II with single component simple chemical enrichment models. However, we can reproduce the form of the distribution if we assume two components, each with a simple model abundance distribution. The "metal-poor" component has mean abundance log (< z >/z(sun))= -1.6, while the "metal-rich" one has mean abundance log (< z >/z(sun))= -0.95 and is outnumbered by the metal-poor population by a ratio of similar to 2.3 to 1. We end by concluding that the diversity of evolutionary histories evident among the Galactic dSph companions is now also firmly established among the dSph satellites of M31. An appendix discusses minor revisions to our earlier And I results that arise from the calibration and analysis techniques adopted in this paper. In particular, our comparisons with ground-based photometry indicate that the zero point for the WFPC2 F450W to B transformation should be modified, by 0.055 mag, to produce fainter B magnitudes and thus redder B-V colors. C1 Australian Natl Univ, Res Sch Astron & Astrophys, Inst Adv Studies, Weston, ACT 2611, Australia. Kitt Peak Natl Observ, Natl Opt Astron Observ, Tucson, AZ 85726 USA. Smithsonian Inst, FL Whipple Observ, Amado, AZ 85645 USA. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. RP Da Costa, GS (reprint author), Australian Natl Univ, Res Sch Astron & Astrophys, Inst Adv Studies, Private Bag,Weston Creek PO, Weston, ACT 2611, Australia. NR 77 TC 56 Z9 56 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD FEB PY 2000 VL 119 IS 2 BP 705 EP 726 DI 10.1086/301223 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 283KX UT WOS:000085275700023 ER PT J AU Barmby, P Huchra, JP Brodie, JP Forbes, DA Schroder, LL AF Barmby, P Huchra, JP Brodie, JP Forbes, DA Schroder, LL TI M31 globular clusters: Colors and metallicities SO ASTRONOMICAL JOURNAL LA English DT Review DE galaxies : individual (M31); galaxies : star clusters; globular clusters : general ID INTEGRATED BVR PHOTOMETRY; INFRARED PHOTOMETRY; OUTER-HALO; MILKY-WAY; STELLAR POPULATIONS; NEARBY GALAXIES; STANDARD STARS; LOCAL GROUP; SYSTEM; KINEMATICS AB We present a new catalog of photometric and spectroscopic data on M31 globular clusters (GCs), The catalog includes new optical and near-infrared photsmetry for a substantial fraction of the 435 clusters and cluster candidates. We use these data to determine the reddening and intrinsic colors of individual clusters, and we find that the extinction laws in the Galaxy and M31 are not significantly different. There are significant (up to 0.2 mag in V-K) offsets between the clusters' intrinsic colors and simple stellar population colors predicted by population synthesis models; we suggest that these are due to systematic errors in the models. The distributions of M31 clusters' metallicities and metallicity-sensitive colors are bimodal, with peaks at [Fe/H] approximate to -1.4 and -0.6, The distribution of V-I is often bimodal in elliptical galaxies' globular cluster systems, but it is not sensitive enough to metallicity to show bimodality in M31 and Galactic cluster systems. The radial distribution and kinematics of the two M31 metallicity groups imply that they are analogs of the Galactic "halo" and "disk/bulge" cluster systems. The globular clusters in M31 have a small radial metallicity gradient, suggesting that some dissipation occurred during the formation of the globular cluster system. The lack of correlation between cluster luminosity and metallicity in M31 GCs shows that self-enrichment is not important in GC formation. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. CALTECH, SIRTF Sci Ctr, Pasadena, CA 91125 USA. RP Barmby, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM pbarmby@cfa.harvard.edu; huchra@cfa.harvard.edu; brodie@ucolick.org; forbes@star.sr.bham.ac.uk; linda@ucolick.org RI Barmby, Pauline/I-7194-2016 OI Barmby, Pauline/0000-0003-2767-0090 NR 107 TC 277 Z9 277 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD FEB PY 2000 VL 119 IS 2 BP 727 EP 747 DI 10.1086/301213 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 283KX UT WOS:000085275700024 ER PT J AU Benson, P Dullighan, A Bonanos, A McLeod, KK Kenyon, SJ AF Benson, P Dullighan, A Bonanos, A McLeod, KK Kenyon, SJ TI An optical study of BG Geminorum: An ellipsoidal binary with an unseen primary star SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : eclipsing; binaries : spectroscopic; stars : emission-line, Be; stars : evolution; stars : individual (BG Gem) ID SPECTRAL ENERGY-DISTRIBUTIONS; BLACK-HOLE; INTERSTELLAR EXTINCTION; SYMBIOTIC STARS; ACCRETION DISK; RZ-OPHIUCHI; MASS; PHOTOMETRY; PASSBANDS; REDSHIFTS AB We describe optical photometric and spectroscopic observations of the bright variable BG Geminorum. Optical photometry shows a pronounced ellipsoidal variation of the K0 I secondary, with amplitudes of similar to 0.5 mag at VRCIC and a period of 91.645 days. A deep primary eclipse is visible for lambda less than or similar to 4400 Angstrom; a shallower secondary eclipse is present at longer wavelengths. Eclipse timings and the radial velocity curve of the K0 secondary star indicate an interacting binary where a lobe-filling secondary, M-2 similar to 0.5 M., transfers material into a extended disk around a massive primary, M-1 similar to 4.5 M.. The primary star is either an early B-type star or a black hole. If it did contain a black hole, BG Gem would be the longest period black hole binary known by a factor of 10, as well as the only eclipsing black hole binary system. C1 Wellesley Coll, Whitin Observ, Wellesley, MA 02181 USA. Swarthmore Coll, Dept Phys & Astron, Swarthmore, PA 19081 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Benson, P (reprint author), Wellesley Coll, Whitin Observ, 106 Cent St, Wellesley, MA 02181 USA. RI Bonanos, Alceste/K-5392-2013; OI Bonanos, Alceste/0000-0003-2851-1905; Kenyon, Scott/0000-0003-0214-609X NR 51 TC 2 Z9 2 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD FEB PY 2000 VL 119 IS 2 BP 890 EP 900 DI 10.1086/301230 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 283KX UT WOS:000085275700036 ER PT J AU Barthel, PD Vestergaard, M Lonsdale, CJ AF Barthel, PD Vestergaard, M Lonsdale, CJ TI Radio imaging of core-dominated high redshift quasars SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : active; galaxies : jets; galaxies : quasars : general ID COMPACT STEEP-SPECTRUM; ACTIVE GALACTIC NUCLEI; VLA OBSERVATIONS; 3CR QUASARS; GALAXIES; MORPHOLOGY; CATALOG; OBJECTS AB VLA imaging at kiloparsec-scale resolution of sixteen core-dominated radio-loud QSOs is presented. Many;objects appear to display variable radio emission and their radio morphologies are significantly smaller than those of steep-spectrum quasars, consistent with these objects being observed at sight lines close to their (relativistic, gamma approximate to 4-7) jet axes. The usefulness of the radio source orientation indicator R-V, being defined as ratio of radio core and rest frame optical V-band luminosity, is confirmed. C1 Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. Copenhagen Univ Observ, NBIFAFG, DK-2100 Copenhagen, Denmark. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Haystack Observ, Westford, MA 01886 USA. RP Barthel, PD (reprint author), Kapteyn Astron Inst, POB 800, NL-9700 AV Groningen, Netherlands. EM pdb@astro.rug.nl RI Vestergaard, Marianne/M-5247-2014 OI Vestergaard, Marianne/0000-0001-9191-9837 NR 38 TC 11 Z9 12 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD FEB PY 2000 VL 354 IS 1 BP 7 EP 16 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295FH UT WOS:000085955700017 ER PT J AU Bodo, G Kalkofen, W Massaglia, S Rossi, P AF Bodo, G Kalkofen, W Massaglia, S Rossi, P TI Acoustic waves in a stratified atmosphere II. Three-dimemsional hydrodynamics SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE hydrodynamics; Sun : chromosphere; waves ID SOLAR CHROMOSPHERE; PROPAGATION; OSCILLATIONS AB We investigate analytically the propagation of linear waves in a three-dimensional, nonmagnetic, isothermal atmosphere stratified in plane-parallel layers. The motivation is to study oscillations in the nonmagnetic chromosphere and to assess the limitations of one-dimensional simulations of the K-2v bright point phenomenon. We consider an impulsively excited acoustic disturbance, emanating from a point source, and propagating outward as a spherical acoustic wave accompanied by an internal gravity wave. The waves amplify exponentially in the upward direction. A significant wave amplitude is therefore found only in a relatively narrow cone about the vertical. The amplitude of the wave decreases with time. Because of the lateral spread, the wave amplitude decays faster in 2D and 3D simulations than in ID. The initial pulse, which travels at the sound speed, carries most of the energy injected into the medium. Subsequent wave crests leave the source region at ever-increasing phase speed, but slow to the sound speed as they approach the head of the wave. Important conclusions from the 3D solution that were not anticipated from the plane-wave solution are: I. The bulk of the energy is emitted in the upward land downward direction; much less goes into the horizontal direction. 2. The wave profile narrows from the initial pulse through the amplitude maxima in the wake of the pulse. As a consequence of both points, the shock-heated regions in the wake of the initial pulse would weaken in strength and shrink in size. 3. The height at which a given wave amplitude is reached spreads outward from the symmetry axis of the disturbance as the wave propagates upward. Thus the diameter of the shock-heated region would increase as the acoustic wave travels upward in the atmosphere. C1 Osservatorio Astron Torino, I-10025 Pino Torinese, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Turin, Dipartimento Fis Gen, I-10125 Turin, Italy. RP Bodo, G (reprint author), Osservatorio Astron Torino, Strada Osservatorio 20, I-10025 Pino Torinese, Italy. EM bodo@to.astro.it; wolf@cfa.harvard.edu; massaglia@ph.unito.it; rossi@to.astro.it RI Bodo, Gianluigi/F-9223-2012; ROSSI, PAOLA/I-7031-2015 OI Bodo, Gianluigi/0000-0002-9265-4081; massaglia, silvano/0000-0003-1779-7426; ROSSI, PAOLA/0000-0002-0840-4726 NR 12 TC 15 Z9 15 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD FEB PY 2000 VL 354 IS 1 BP 296 EP 304 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295FH UT WOS:000085955700045 ER PT J AU Stancil, PC Kirby, K Gu, JP Hirsch, G Buenker, RJ Sannigrahi, AB AF Stancil, PC Kirby, K Gu, JP Hirsch, G Buenker, RJ Sannigrahi, AB TI The formation of SiH+, PH+, and SH+ by radiative association SO ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES LA English DT Article DE molecular processes; ISM : molecules ID INTERSTELLAR CLOUDS; CI CALCULATIONS; ENERGY EXTRAPOLATION; EXCITED-STATES; CHEMISTRY; PERTURBATION; SILICON; CURVES; IONS AB Cross sections for the radiative association of Si+, P+, and S+ with atomic hyrdrogen to form the diatomic molecular ions SiH+, PH+, and SH+, respectively, are presented. The results are obtained using fully quantum-mechanical techniques and utilize ab initio molecular data calculated with the multireference single- and double-excitation configuration-interaction (MRD-CI) method. Thermal rate coefficients are presented and applications of the results to diffuse interstellar clouds are discussed. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Berg Univ Gesamthsch Wuppertal, D-42097 Wuppertal, Germany. Indian Inst Technol, Dept Chem, Kharagpur 721302, W Bengal, India. RP Stancil, PC (reprint author), Oak Ridge Natl Lab, Div Phys, POB 2008, Oak Ridge, TN 37831 USA. NR 30 TC 8 Z9 9 U1 1 U2 3 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 0365-0138 J9 ASTRON ASTROPHYS SUP JI Astron. Astrophys. Suppl. Ser. PD FEB PY 2000 VL 142 IS 1 BP 107 EP 112 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 293EQ UT WOS:000085838900013 ER PT J AU David, LP AF David, LP TI Prospects for detecting clusters of galaxies through X-ray absorption SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : clusters : general; X-rays : galaxies ID ROSAT OBSERVATIONS; EVOLUTION; CONSTRAINTS; ABUNDANCES; QUASARS; RATES; GAS AB We investigate the feasibility of detecting high-redshift clusters in absorption against background active galactic nuclei (AGNs) with the next generation of X-ray telescopes. The four limiting factors for detecting clusters in absorption are the sensitivity of the X-ray spectrometers, the abundance of X-ray-bright AGNs, the absorption equivalent width, and the sky covering factor of the hot gas in clusters. Based on isothermal and polytropic temperature profiles for the gas in clusters, we compute the absorption equivalent widths of the most abundant heavy elements in clusters with emission-weighted temperatures between 1 keV (typical of groups) and 12 keV (typical of the hottest known clusters). For typical AGN X-ray spectra, we find that the easiest lines to detect in absorption arise from He-like Si and S and Fe xx in groups, He-like Fe in 2-10 keV clusters, and H-like Fe in the hottest clusters. The sky covering factor of the hot gas is then determined as a function of absorption equivalent width for a nonevolving cluster population and for evolving cluster populations in an open (Omega = 0.3) and flat (Omega = 1.0) universe. In an open universe, approximately 5% of the sky is covered by hot gas with an equivalent width greater than 1 eV for He-like Fe absorption. In a high-density universe, the corresponding sky covering factor is only 1%. Based on the X-ray luminosity function of AGNs, we find that there are several thousand AGNs beyond z = 1 and several hundred AGNs beyond z = 2 that are bright enough to produce detectable absorption features in clusters with future X-ray calorimeters. These results show that an observing program of high-redshift, X-ray-bright AGNs will have the added benefit of detecting a significant sample of high-redshift clusters. High-redshift clusters can easily be missed in X-ray imaging surveys, since their X-ray surface brightness can be below the X-ray background. C1 Harvard Smithsonian Ctr Astrophys, Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP David, LP (reprint author), Harvard Smithsonian Ctr Astrophys, Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 49 TC 3 Z9 3 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 1 PY 2000 VL 529 IS 2 BP 682 EP 691 DI 10.1086/308297 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287UL UT WOS:000085524800007 ER PT J AU Sakai, S Mould, JR Hughes, SMG Huchra, JP Macri, LM Kennicutt, RC Gibson, BK Ferrarese, L Freedman, WL Han, MS Ford, HC Graham, JA Illingworth, GD Kelson, DD Madore, BF Sebo, K Silbermann, NA Stetson, PB AF Sakai, S Mould, JR Hughes, SMG Huchra, JP Macri, LM Kennicutt, RC Gibson, BK Ferrarese, L Freedman, WL Han, MS Ford, HC Graham, JA Illingworth, GD Kelson, DD Madore, BF Sebo, K Silbermann, NA Stetson, PB TI The Hubble Space Telescope Key Project on the Extragalactic Distance Scale. XXIV. The calibration of Tully-Fisher relations and the value of the hubble constant SO ASTROPHYSICAL JOURNAL LA English DT Review DE distance scale; galaxies : distances and redshifts galaxies : kinematics and dynamics; galaxies : photometry ID VELOCITY-WIDTH RELATION; NEUTRAL HYDROGEN OBSERVATIONS; CENTIMETER LINE WIDTHS; SPIRAL GALAXIES; H-I; VIRGO CLUSTER; INFRARED MAGNITUDE; MALMQUIST BIAS; CEPHEID DISTANCE; NEARBY GALAXIES AB This paper presents the calibration of BVRIH(-0.5) Tully-Fisher relations based on Cepheid distances to 21 galaxies within 25 Mpc and 23 clusters within 10,000 km s(-1). These relations have been applied to several distant cluster surveys in order to derive a value for the Hubble constant, H(0), mainly concentrating on an I-band all-sky survey by Giovanelli and collaborators, consisting of total I magnitudes and 50% line width data for similar to 550 galaxies in 16 clusters. For comparison, we also derive the values of H(0) using surveys in the B and V bands by Bothun and collaborators, and in H band by Aaronson and collaborators. Careful comparisons with various other databases from the literature suggest that the H-band data, which have isophotal magnitudes extrapolated from aperture magnitudes rather than total magnitudes, are subject to systematic uncertainties. Taking a weighted average of the estimates of Hubble constants from four surveys, we obtain H(0) = 71 +/- 4 (random) +/- 7 (systematic). We have also investigated how the value of H(0) is affected by various systematic uncertainties, such as the internal extinction correction method used, Tully-Fisher slopes and shapes, a possible metallicity dependence of the Cepheid period-luminosity relation, and cluster population incompleteness bias. C1 Kitt Peak Natl Observ, Natl Opt Astron Observ, Tucson, AZ 85726 USA. Australian Natl Univ, Mt Stromol Observ, Inst Adv Studies, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. CALTECH, Pasadena, CA 91125 USA. Carnegie Observ, Pasadena, CA 91101 USA. Avanti Corp, Fremont, CA 94538 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. CALTECH, IPAC, Pasadena, CA 91125 USA. Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. RP Sakai, S (reprint author), Kitt Peak Natl Observ, Natl Opt Astron Observ, POB 26732, Tucson, AZ 85726 USA. RI Gibson, Brad/M-3592-2015 OI Gibson, Brad/0000-0003-4446-3130 NR 135 TC 174 Z9 174 U1 0 U2 2 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 FEB 1 PY 2000 VL 529 IS 2 BP 698 EP 722 DI 10.1086/308305 PN 1 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287UL UT WOS:000085524800009 ER PT J AU Ferrarese, L Mould, JR Kennicutt, RC Huchra, J Ford, HC Freedman, WL Stetson, PB Madore, BF Sakai, S Gibson, BK Graham, JA Hughes, SM Illingworth, GD Kelson, DD Macri, L Sebo, K Silbermann, NA AF Ferrarese, L Mould, JR Kennicutt, RC Huchra, J Ford, HC Freedman, WL Stetson, PB Madore, BF Sakai, S Gibson, BK Graham, JA Hughes, SM Illingworth, GD Kelson, DD Macri, L Sebo, K Silbermann, NA TI The Hubble Space Telescope Key Project on the Extragalactic Distance Scale. XXVI. The calibration of population II secondary distance indicators and the value of the hubble constant SO ASTROPHYSICAL JOURNAL LA English DT Article DE Cepheids; distance scale; galaxies : star clusters; stars : late-type ID RED-GIANT-BRANCH; SURFACE BRIGHTNESS FLUCTUATIONS; NEBULA LUMINOSITY FUNCTION; GLOBULAR-CLUSTER SYSTEM; PLANETARY-NEBULAE; STANDARD CANDLES; VIRGO CLUSTER; INFRARED PHOTOMETRY; ELLIPTIC GALAXIES; COMA CLUSTER AB A Cepheid-based calibration is derived for four distance indicators that utilize stars in old stellar populations: the tip of the red giant branch (TRGB), the planetary nebula luminosity function (PNLF), the globular cluster luminosity function (GCLF), and the surface brightness fluctuation method (SBF). The calibration is largely based on the Cepheid distances to 18 spiral galaxies within ct = 1500 km s(-1) obtained as part of the Hubble Space Telescope (HST) Key Project on the Extragalactic Distance Scale, but relies also on Cepheid distances from separate HST and ground-based efforts. The newly derived calibration of the SBF method is applied to obtain distances to four Abell clusters in the velocity range 3800-5000 km s(-1). Combined with cluster velocities corrected for a cosmological flow model, these distances imply a value of the Hubble constant of H-0 = 69 +/- 4 (random) +/- 6 (systematic) km s(-1) Mpc(-1). This result assumes that the Cepheid PL relation is independent of the metallicity of the variable stars; adopting a metallicity correction as in Kennicutt et al. would produce a 5% +/- 3% decrease in H-0. Finally, the newly derived calibration allows us to investigate systematics in the Cepheid, PNLF, SBF, GCLF, and TRGB distance scales. C1 CALTECH, Pasadena, CA 91125 USA. Australian Natl Univ, Inst Adv Studies, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Carnegie Observ, Pasadena, CA 91101 USA. Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. NASA, IPAC Extragalact Database, Pasadena, CA 91125 USA. CALTECH, Pasadena, CA 91125 USA. Natl Opt Astron Observ, Kitt Peak Natl Observ, Tucson, AZ 85726 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Royal Greenwich Observ, Cambridge CB3 0HA, England. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. RP Ferrarese, L (reprint author), CALTECH, Pasadena, CA 91125 USA. RI Gibson, Brad/M-3592-2015 OI Gibson, Brad/0000-0003-4446-3130 NR 99 TC 172 Z9 173 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 1 PY 2000 VL 529 IS 2 BP 745 EP 767 DI 10.1086/308309 PN 1 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287UL UT WOS:000085524800011 ER PT J AU Kelson, DD Illingworth, GD Tonry, JL Freedman, WL Kennicutt, RC Mould, JR Graham, JA Huchra, JP Macri, LM Madore, BF Ferrarese, L Gibson, BK Sakai, S Stetson, PB Ajhar, EA Blakeslee, JP Dressler, A Ford, HC Hughes, SMG Sebo, KM Silbermann, NA AF Kelson, DD Illingworth, GD Tonry, JL Freedman, WL Kennicutt, RC Mould, JR Graham, JA Huchra, JP Macri, LM Madore, BF Ferrarese, L Gibson, BK Sakai, S Stetson, PB Ajhar, EA Blakeslee, JP Dressler, A Ford, HC Hughes, SMG Sebo, KM Silbermann, NA TI The Hubble Space Telescope Key Project on the Extragalactic Distance Scale. XXVII. A derivation of the hubble constant using the fundamental plane and D-n-sigma relations in Leo I, Virgo, and Fornax SO ASTROPHYSICAL JOURNAL LA English DT Article DE Cepheids; galaxies : distances and redshifts; distance scale ID EARLY-TYPE GALAXIES; ELLIPTICAL GALAXIES; VELOCITY DISPERSIONS; SAMPLE SELECTION; CLUSTERS; PHOTOMETRY; SPECTROSCOPY; CALIBRATION; CATALOG; PROFILES AB Using published photometry and spectroscopy, we construct the fundamental plane and D-n-sigma relations in Leo I, Virgo, and Fornax. The published Cepheid period-luminosity (PL) relations to spirals in these clusters fixes the relation between angular size and metric distance for both the fundamental plane and D-n-sigma relations. Using the locally calibrated fundamental plane, we infer distances to a sample of clusters with a mean redshift of ct approximate to 6000 km s(-1), and derive a value of H-0 = 78 +/- 5 +/- 9 km s(-1) Mpc(-1) (random and systematic errors, respectively) for the local expansion rate. This value includes a correction for depth effects in the Cepheid distances to the nearby clusters, which decreased the deduced value of the expansion rate by 5% +/- 5%. If one further adopts the metallicity correction to the Cepheid PL relation as derived by the Key Project, the value of the Hubble constant would decrease by a further 6% +/- 4%. These two sources of systematic error, when combined with a +/-6% error due to the uncertainty in the distance to the Large Magellanic Cloud, a +/-4% error due to uncertainties in the WFPC2 calibration, and several small sources of uncertainty in the fundamental plane analysis, yield a total systematic uncertainty of +/-11%. We find that the values obtained using either the cosmic microwave background (CMB) or a how-held model, for the reference frame of the distant dusters, agree to within 1%. The D-n-sigma relation also produces similar results, as expected from the correlated nature of the two scaling relations. A complete discussion of the sources of random and systematic error in this determination of the Hubble constant is also given, in order to facilitate comparison with the other secondary indicators being used by the Key Project. C1 Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Board Studies Astron & Astrophys, Santa Cruz, CA 95064 USA. Inst Astron, Honolulu, HI 96822 USA. Carnegie Observ, Pasadena, CA 91101 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Australian Natl Univ, Inst Adv Studies, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, IPAC, Pasadena, CA 91125 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Space Telescope Inst, Baltimore, MD 21218 USA. Royal Greenwich Observ, Cambridge CB3 0EZ, England. RP Kelson, DD (reprint author), Carnegie Inst Washington, Dept Terr Magnetism, 5241 Broad Branch Rd NW, Washington, DC 20015 USA. RI Gibson, Brad/M-3592-2015 OI Gibson, Brad/0000-0003-4446-3130 NR 66 TC 66 Z9 67 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 1 PY 2000 VL 529 IS 2 BP 768 EP 785 DI 10.1086/308310 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287UL UT WOS:000085524800012 ER PT J AU Mould, JR Huchra, JP Freedman, WL Kennicutt, RC Ferrarese, L Ford, HC Gibson, BK Graham, JA Hughes, SMG Illingworth, GD Kelson, DD Macri, LM Madore, BF Sakai, S Sebo, KM Silbermann, NA Stetson, PB AF Mould, JR Huchra, JP Freedman, WL Kennicutt, RC Ferrarese, L Ford, HC Gibson, BK Graham, JA Hughes, SMG Illingworth, GD Kelson, DD Macri, LM Madore, BF Sakai, S Sebo, KM Silbermann, NA Stetson, PB TI The Hubble Space Telescope Key Project on the Extragalactic Distance Scale. XXVIII. Combining the constraints on the hubble constant SO ASTROPHYSICAL JOURNAL LA English DT Article DE Cepheids; cosmology : observations; distance scale; galaxies : distances and redshifts ID PECULIAR VELOCITY-FIELD; LOCAL SUPERCLUSTER; CEPHEID DISTANCE; ELLIPTICAL GALAXIES; EXPANSION RATE; IA SUPERNOVAE; UNIVERSE; DENSITY; MOTIONS; CLUSTER AB Since the launch of Hubble Space Telescope (HST) 9 yr ago, Cepheid distances to 25 galaxies have been determined for the purpose of calibrating secondary distance indicators. Eighteen of these have been measured by the HST Key Project team, sir; by the Supernova Calibration Project, and one independently by Tanvir. Collectively, this work; sets out an array of survey markers over the region within 25 Mpc of the Milky Way. A variety of secondary distance indicators can now be calibrated, and the accompanying four papers employ the full set of 25 galaxies to consider the Tully-Fisher relation, the fundamental plane of elliptical galaxies, Type Ia supernovae, and surface brightness fluctuations. When calibrated with Cepheid distances, each of these methods yields a measurement of the Hubble constant and a corresponding measurement uncertainty. We combine these measurements in this paper, together with a model of the velocity held, to yield the best available estimate of the value of H-0 within the range of these secondary distance indicators and its uncertainty. The uncertainty in the result is modeled in an extensive simulation we call the "virtual Key Project." The velocity-held model includes the influence of the Virgo cluster, the Great Attractor, and the Shapley supercluster, but does not play a significant part in determining the result. The result is H-0 = 71 +/- 6 km s(-1) Mpc(-1). The largest contributor to the uncertainty of this 67% confidence level result is the distance of the Large Magellanic Cloud, which has been assumed to be 50 +/- 3 kpc. This takes up the first 6.5% of our 9% error budget. Other contributors are the photometric calibration of the WFPC2 instrument, which takes up 4.5%, deviations from uniform Hubble flow in the volume sampled (less than or similar to 2%), the composition sensitivity of the Cepheid period-luminosity relation (4%), and departures from a universal reddening law (similar to 1%). These are the major components that, when combined in quadrature, make up the 9% total uncertainty. If the LMC distance modulus were systematically smaller by 1 sigma than that adopted here, the derived value of the Hubble constant would increase by 4 km s(-1) Mpc(-1). Most of the significant systematic errors are capable of amelioration in future work. These include the uncertainty in the photometric calibration of WFPC2, the LMC distance, and the reddening correction. A NICMOS study is in its preliminary reduction phase, addressing the last of these concerns. Various empirical analyses have suggested that Cepheid distance moduli are affected by metallicity differences. If we adopted the composition sensitivity obtained in the Key Project's study of M101, and employed the oxygen abundances measured spectroscopically in each of the Cepheid fields we have studied, the value of the Hubble constant would be reduced by 4% +/- 2% to 68 +/- 6 km s(-1) Mpc(-1). C1 Australian Natl Univ, Mt Stromlo Observ, Inst Adv Studies, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Colorado, CASA, Boulder, CO 80309 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Royal Greenwich Observ, Cambridge CB3 0EZ, England. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. Natl Res Council Canada, Herzberg Inst Astrophys, Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. RP Mould, JR (reprint author), Australian Natl Univ, Mt Stromlo Observ, Inst Adv Studies, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. RI Gibson, Brad/M-3592-2015 OI Gibson, Brad/0000-0003-4446-3130 NR 51 TC 358 Z9 359 U1 2 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 1 PY 2000 VL 529 IS 2 BP 786 EP 794 DI 10.1086/308304 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287UL UT WOS:000085524800013 ER PT J AU Colley, WN Gott, JR Weinberg, DH Park, C Berlind, AA AF Colley, WN Gott, JR Weinberg, DH Park, C Berlind, AA TI Topology from the simulated Sloan Digital Sky Survey SO ASTROPHYSICAL JOURNAL LA English DT Review DE galaxies : distances and redshifts; methods : n-body simulations; surveys ID LARGE-SCALE STRUCTURE; COLD DARK-MATTER; CAMPANAS REDSHIFT SURVEY; N-BODY SIMULATIONS; MICROWAVE BACKGROUND FLUCTUATIONS; NONZERO COSMOLOGICAL CONSTANT; OPEN UNIVERSE; ELLIPTICAL GALAXIES; 2-DIMENSIONAL TOPOLOGY; DENSITY PERTURBATIONS AB We measure the topology (genus curve) of the galaxy distribution in a very large cosmological simulation designed to resemble closely results from the upcoming Sloan Digital Sky Survey (SDSS). The mock survey is based on a large N-body simulation that uses 54,872,000 particles in a periodic cube 600 h(-1) Mpc on a side. The adopted inflationary cold dark matter (CDM) model has parameters Omega(CDM) = 0.4, Omega(Lambda) = 0.6, h = 0.6, b = 1.3. We "observe" this simulation to produce a simulated redshift catalog of similar to 10(6) galaxies over pi steradians, mimicking the anticipated spectroscopic selection procedures of the SDSS in some detail. Sky maps, redshift slices, and three-dimensional contour maps of the mock survey reveal a rich and complex structure, including networks of voids and superclusters that resemble the patterns seen in the CfA redshift survey and the Las Campanas Redshift Survey (LCRS). The three-dimensional genus curve can be measured from the simulated catalog with superb precision; this curve not only has the general shape predicted for Gaussian, random phase initial conditions, but the error bars are small enough to demonstrate with high significance the subtle departures from this shape caused by nonlinear gravitational evolution on a 10 h(-1) Mpc smoothing scale (where sigma(gal) = 0.4). These distortions have the form predicted by Matsubara's perturbative analysis, but they are smaller in amplitude. We also measure the three-dimensional genus curve of the radial peculiar velocity field measured by applying distance-indicator relations (with realistic errors) to the mock catalog. The genus curve is consistent with the Gaussian random phase prediction, though it is of relatively low precision because of the large smoothing length required to overcome noise in the measured velocity held. Finally, we measure the two-dimensional topology in redshift slices, similar to those which will become available early in the course of the SDSS and to those already observed in the LCRS. The genus curves of these slices are consistent with the observed genus curves of the LCRS, suggesting that our inflationary CDM model with Omega(CDM) similar to 0.4 is a good choice. Our mock redshift catalog is publicly available for the use of other researchers. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Seoul Natl Univ, Dept Astron, Seoul 151, South Korea. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM wcolley@cfa.harvard.edu; jrg@astro.princeton.edu; dhw@astronomy.ohio-state.edu; cbp@astro.snu.ac.kr; aberlind@astronomy.ohio-state.edu NR 129 TC 22 Z9 22 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 FEB 1 PY 2000 VL 529 IS 2 BP 795 EP 810 DI 10.1086/308289 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287UL UT WOS:000085524800014 ER PT J AU Jansen, RA Franx, M Fabricant, D Caldwell, N AF Jansen, RA Franx, M Fabricant, D Caldwell, N TI Surface photometry of nearby field galaxies: The data SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE atlases; galaxies : fundamental parameters; galaxies : photometry; galaxies : stellar content; surveys ID DISK DOMINATED GALAXIES; CFA REDSHIFT SURVEY; SPIRAL GALAXIES; LUMINOSITY FUNCTION; VIRGO CLUSTER; BRIGHTNESS; STELLAR; MAGNITUDES; SELECTION; CATALOG AB We have obtained integrated spectra and multifilter photometry for a representative sample of similar to 200 nearby galaxies. These galaxies span the entire Hubble sequence in morphological type, as well as a wide range of luminosities (M(B) = -14 to -22) and colors (B-R = 0.4-1.8). Here we describe the sample selection criteria and the U, B, R surface photometry for these galaxies. The spectrophotometric results will be presented in a companion paper. Our goals for the project include measuring the current star formation rates and metallicity of these galaxies, and elucidating their star formation histories, as a function of luminosity and morphology. We thereby extend the work of Kennicutt to lower luminosity systems. We anticipate that our study will be useful as a benchmark for studies of galaxies at high red-shift. We discuss the observing, data reduction, and calibration techniques and show that our photometry agrees well with previous work in those cases in which earlier data are available. We present an atlas of images, radial surface brightness profiles, and color profiles as well as tables of derived parameters. The atlas and tables of measurements will be made available electronically. We study the correlations of galaxy properties determined from the galaxy images. Our findings include the following: (1) colors determined within the effective radius correlate better with morphological type than with M(B) and (2) 50% of the low-luminosity galaxies are bluest in their centers. C1 Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. FL Whipple Observ, Amado, AZ 85645 USA. RP Jansen, RA (reprint author), Univ Groningen, Kapteyn Astron Inst, Postbus 800, NL-9700 AV Groningen, Netherlands. EM jansen@astro.rug.nl; franx@strw.leidenuniv.nl; dfabricant@cfa.harvard.edu; ncaldwell@cfa.harvard.edu NR 43 TC 115 Z9 116 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD FEB PY 2000 VL 126 IS 2 BP 271 EP 329 DI 10.1086/313303 PG 59 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 308VA UT WOS:000086732500003 ER PT J AU Jansen, RA Fabricant, D Franx, M Caldwell, N AF Jansen, RA Fabricant, D Franx, M Caldwell, N TI Spectrophotometry of nearby field galaxies: The data SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE atlases; galaxies : fundamental parameters; galaxies : ISM; galaxies : stellar content; surveys ID SPECTRAL ENERGY-DISTRIBUTIONS; STAR-FORMING GALAXIES; CFA REDSHIFT SURVEY; LUMINOSITY FUNCTION; ULTRAVIOLET; EVOLUTION AB We have obtained integrated and nuclear spectra as well as U, B, R surface photometry for a representative sample of 196 nearby galaxies. These galaxies span the entire Hubble sequence in morphological type, as well as a wide range of luminosities (M(B) = -14 to -22). Here we present the spectrophotometry for these galaxies. The selection of the sample and the U, B, R surface photometry is described in a companion paper. Our goals for the project include measuring the current star formation rates and metallicities of these galaxies, and elucidating their star formation histories, as a function of luminosity and morphology. We thereby extend the work of Kennicutt to lower luminosity systems. We anticipate that our study will be useful as a benchmark for studies of galaxies at high redshift. We describe the observing, data reduction, and calibration techniques and demonstrate that our spectrophotometry agrees well with that of Kennicutt. The spectra span the range 3550-7250 Angstrom, at a resolution (FWHM) of similar to 6 Angstrom and have an overall relative spectrophotometric accuracy of similar to +/- 6%. We present a spectrophotometric atlas of integrated and nuclear rest-frame spectra as well as tables of equivalent widths and synthetic colors. The atlas and tables of measurements will be made available electronically. We study the correlations of galaxy properties determined from the spectra and images. Our findings include: (1) galaxies of a given morphological class display a wide range of continuum shapes and emission-line strengths if a broad range of luminosities are considered, (2) emission-line strengths tend to increase and continua tend to get bluer as the luminosity decreases, and (3) the scatter on the general correlation between nuclear and integrated H alpha emission-line strengths is large. C1 Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. FL Whipple Observ, Amado, AZ 85645 USA. RP Jansen, RA (reprint author), Univ Groningen, Kapteyn Astron Inst, Postbus 800, NL-9700 AV Groningen, Netherlands. EM jansen@astro.rug.nl; dfabricant@cfa.harvard.edu; franx@strw.leidenuniv.nl; ncaldwell@cfa.harvard.edu NR 25 TC 168 Z9 169 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD FEB PY 2000 VL 126 IS 2 BP 331 EP 397 DI 10.1086/313308 PG 67 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 308VA UT WOS:000086732500004 ER PT J AU Jennions, MD Petrie, M AF Jennions, MD Petrie, M TI Why do females mate multiply? A review of the genetic benefits SO BIOLOGICAL REVIEWS LA English DT Review DE cryptic female choice; Fisherian runaway; genetic diversity; genetic incompatibility; genetic benefits; good genes; mate choice; multiple mating; polyandry; sexual selection; sperm competition ID EXTRA-PAIR PATERNITY; SPERM COMPETITION GAMES; RED-WINGED BLACKBIRDS; YELLOW DUNG FLY; DROSOPHILA-MELANOGASTER FEMALES; ASCIDIAN DIPLOSOMA-LISTERIANUM; SOCIAL INSECT COLONIES; LIFE-HISTORY TRAITS; MALE MATING SUCCESS; GREAT REED WARBLER AB The aim of this review is to consider the potential benefits that females may gain from mating more than once in a single reproductive cycle. The relationship between non-genetic and genetic benefits is briefly explored. We suggest that multiple mating for purely non-genetic benefits is unlikely as it invariably leads to the possibility of genetic benefits as well. We begin by briefly reviewing the main models for genetic benefits to mate choice, and the supporting evidence that choice can increase offspring performance and the sexual attractiveness of sons. We then explain how multiple matin!: can elevate offspring fitness by increasing the number of potential sires that compete, when this occurs in conjunction with mechanisms of paternity biasing that function in copula or post-copulation. We begin by identifying cases where females use precopulatory cues to identify mates prior to remating. In the simplest case, females remate because they identify a superior mate and 'trade up' genetically. The main evidence for this process comes from extra-pair copulation in birds. Second, we note other cases where pre-copulatory cues may be less reliable and females mate with several males to promote post-copulatory mechanisms that bias paternity. Although a distinction is drawn between sperm competition and cryptic female choice, we point out that the genetic benefits to polyandry in terms of producing more viable or sexually attractive offspring do not depend on the exact mechanism that leads to biased paternity. Post-copulatory mechanisms of paternity biasing may: (1) reduce genetic incompatibility between male and female genetic contributions to offspring; (2) increase offspring viability if there is a positive correlation between traits favoured post-copulation and those that improve performance under natural selection; (3) increase the ability of sons to gain paternity when they mate with polyandrous females. A third possibility is that genetic diversity among offspring is directly favoured. This can be due to bet-hedging (due to mate assessment errors or temporal fluctuations in the environment), beneficial interactions between less related siblings of the opportunity to preferentially fertilise eggs with sperm of a specific genotype drawn from a range of stored sperm depending on prevailing environmental conditions. We use case studies from the social insects to provide some concrete examples of the role of genetic diversity among progeny in elevating fitness. We conclude that post-copulatory mechanisms provide a more reliable way of selecting a genetically compatible mate than pre-copulatory mate choice. Some of the best evidence for cryptic female choice by sperm selection is due to selection of more compatible sperm. Two future areas of research seem likely to be profitable. First, more experimental evidence is needed demonstrating that multiple mating increases offspring fitness via genetic gains. Second, the role of multiple mating in promoting assortative fertilization and increasing reproductive isolation between populations may help us to understand sympatric speciation. C1 Smithsonian Trop Res Inst, Balboa, Panama. Newcastle Univ, Dept Psychol, Evolut & Behav Res Grp, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England. RP Jennions, MD (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. EM jennionm@naos.si.edu RI Jennions, Michael/C-7560-2009 OI Jennions, Michael/0000-0001-9221-2788 NR 368 TC 1175 Z9 1189 U1 54 U2 506 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1464-7931 J9 BIOL REV JI Biol. Rev. PD FEB PY 2000 VL 75 IS 1 BP 21 EP 64 DI 10.1017/S0006323199005423 PG 44 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 297HU UT WOS:000086077500002 PM 10740892 ER PT J AU Roberts, DL Cooper, RJ Petit, LJ AF Roberts, DL Cooper, RJ Petit, LJ TI Use of premontane moist forest and shade coffee agroecosystems by army ants in western Panama SO CONSERVATION BIOLOGY LA English DT Article ID TROPICAL AGROECOSYSTEM; BIODIVERSITY; CONSERVATION; DIVERSITY; PATTERNS; MEXICO AB Two species of Neotropical army ant, Eciton burchelli and Labidus praedator (Hymenoptera: Formicidae: Ecitoninae), are swarm-raiding species that require large areas of habitat in which to hunt. Behavioral and distributional studies of these two species have been confined largely to humid lowland forest. We conducted intensive systemic area searches at elevations between 1200 and 1800 m in western Panama to assess the distribution of both species in intact premontane moist forest, shade coffee plantations close to forest, and shade coffee plantations distant from forest. Neither species was observed in sun coffee farm contributes to the persistence of these forest organisms in modified landscapes. Large canopy trees not only provide shade that buffers temperature extremes but also supply the ground layer with regular inputs of leaf litter and coarse woody debris as nesting sites (bivouacs). There were significantly fewer potential bivouacs available in sun coffee plantations than in forest and shade coffee habitats. Also, it litter depth was less in sun coffee than in forest and shade coffee. Our results provide the first evidence that shade coffee plantations can provide additional habitat for E. burchelli and L. praedator, top predators of the leaf litter arthropod community. E. burchelli and L. praedator act as critical links between swarm-attendant bird species and leaf-litter arthopods, providing an easily exploited food resource that would otherwise be unavailable for many birds. Continued conversion of shade coffee plantations to sun coffee plantations could bare negative effects on army ants and associated biodiversity. C1 Univ Georgia, Warnell Sch Forest Resources, Athens, GA 30602 USA. Natl Zool Pk, Smithsonian Migratory Bird Ctr, Washington, DC 20008 USA. RP Roberts, DL (reprint author), Univ Georgia, Warnell Sch Forest Resources, Athens, GA 30602 USA. NR 44 TC 44 Z9 47 U1 0 U2 15 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD FEB PY 2000 VL 14 IS 1 BP 192 EP 199 DI 10.1046/j.1523-1739.2000.98522.x PG 8 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 285AV UT WOS:000085366700024 ER PT J AU Wright, SJ Zeballos, H Dominguez, I Gallardo, MM Moreno, MC Ibanez, R AF Wright, SJ Zeballos, H Dominguez, I Gallardo, MM Moreno, MC Ibanez, R TI Poachers alter mammal abundance, seed dispersal, and seed predation in a neotropical forest SO CONSERVATION BIOLOGY LA English DT Article ID PALM ASTROCARYUM-STANDLEYANUM; PECCARIES TAYASSU-TAJACU; PROECHIMYS-SEMISPINOSUS; SPINY RATS; RECRUITMENT; PANAMA; PECARI AB We evaluated the hypothesis that poachers reduce the abundance of herbivorous mammals, and that this, in turn, alters seed dispersal seed predation, and seedling recruitment for two palms (Attalea butyraceae and Astrocaryum standleyanum) in central Panama. Using physical evidence left by poachers and interviews with forest guards, we quantified poaching intensity for eight forest sites. We quantified mammal abundance using transect counts and small-mammal traps Abundance was inversely related to poaching intensity for 9 of 11 mammal species (significantly so for 5 species), confirming the first component of the hypothesis. The outcome of interactions among seeds, mammals, and beetles also varied with Poaching intensity: Nonvolant mammals were the only seed-dispersal agents, and rodents and beetles were the only seed predators. We quantified seed fate by examining the stony, endocarps that encase the seeds of both palms. The large, durable endocarps were located easily on the forest floor and bear characteristic scars when a rodent or beetle eats the enclosed seed The proportion of seeds dispersed away from beneath fruiting conspecifics ;was inversely related to poaching intensity, ranging from 0% to 10% at protected sites where mammals were abundant and from 3% to 40% at unprotected sites where poachers were most active. The proportion of dispersed seeds destroyed by beetles was directly related to poaching intensity, ranging from 85% to 99% at protected sites and from 30% to 50% at unprotected sites. The proportion of dispersed seeds destroyed by rodents was inversely related to poaching intensity, ranging from 85% to 99% at protected sites and from 4% to 50% at at unprotected sites. Finally, seedling densities were directly related to poaching intensity. There was no single relationship between poaching intensity and the biotic interactions that determine seedling recruitment. The net effect of poaching on seedling recruitment can be determined only empirically. For these palms, seedling densities were directly, related to poaching intensity. C1 Smithsonian Trop Res Inst, Balboa, Ancon, Panama. Prodefensa Naturaleza Arequipa, Miraflores, Arequipa, Peru. Inst Nacl Recursos Nat Renovables, Direccion Nacl Cuencas Hidrog, Panama City, Panama. RP Wright, SJ (reprint author), Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. RI Wright, Stuart/M-3311-2013 OI Wright, Stuart/0000-0003-4260-5676 NR 42 TC 174 Z9 187 U1 6 U2 44 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD FEB PY 2000 VL 14 IS 1 BP 227 EP 239 DI 10.1046/j.1523-1739.2000.98333.x PG 13 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 285AV UT WOS:000085366700028 ER PT J AU Culver, SJ Buzas, MA AF Culver, SJ Buzas, MA TI Global latitudinal species diversity gradient in deep-sea benthic foraminifera SO DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS LA English DT Article DE benthic foraminifera; diversity; latitudinal gradient ID ASSEMBLAGES; PHYTODETRITUS; SEDIMENTATION; BIODIVERSITY; TEMPERATE; ATLANTIC; ECOLOGY AB Global scale patterns of species diversity for modern deep-sea benthic foraminifera, an important component of the bathyal and abyssal meiofauna, are examined using comparable data from five studies in the Atlantic, ranging over 138 degrees of latitude from the Norwegian Sea to the Weddell Sea. We show that a pattern of decreasing diversity with increasing latitude characterises both the North and South Atlantic. This pattern is confirmed for the northern hemisphere by independent data from the west-central North Atlantic and the Arctic basin. Species diversity in the North Atlantic northwards from the equator is variable until a sharp fall in the Norwegian Sea (ca. 65 degrees N). In the South Atlantic species diversity drops from a maximum in latitudes less than 30 degrees S and then decreases slightly from 40 to 70 degrees S. For any given latitude, North Atlantic diversity is generally lower than in the South Atlantic. Both ecological and historical factors related to food supply are invoked to explain the formation and maintenance of the latitudinal gradient of deep-sea benthic foraminiferal species diversity. The gradient formed some 36 million years ago when global climatic cooling led to seasonally fluctuating food supply in higher latitudes. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Nat Hist Museum, Dept Palaeontol, London SW7 5BD, England. Smithsonian Inst, Natl Museum Amer Hist, Dept Paleobiol, Washington, DC 20560 USA. RP Culver, SJ (reprint author), E Carolina Univ, Dept Geol, Greenville, NC 27858 USA. NR 41 TC 78 Z9 79 U1 0 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0637 J9 DEEP-SEA RES PT I JI Deep-Sea Res. Part I-Oceanogr. Res. Pap. PD FEB PY 2000 VL 47 IS 2 BP 259 EP 275 DI 10.1016/S0967-0637(99)00055-2 PG 17 WC Oceanography SC Oceanography GA 265TR UT WOS:000084262300005 ER PT J AU Clark, ME Wolcott, TG Wolcott, DL Hines, AH AF Clark, ME Wolcott, TG Wolcott, DL Hines, AH TI Foraging behavior of an estuarine predator, the blue crab Callinectes sapidus in a patchy environment SO ECOGRAPHY LA English DT Article ID OYSTERCATCHERS HAEMATOPUS-OSTRALEGUS; PREY SIZE-SELECTION; MYTILUS-EDULIS BEDS; CHESAPEAKE BAY; PLACOPECTEN-MAGELLANICUS; MICROHABITAT SELECTION; HOMARUS-AMERICANUS; CANCER-IRRORATUS; FEEDING BIVALVES; SEA SCALLOPS AB To define general principles of predator-prey dynamics in an estuarine subtidal environment, we manipulated predator density (the blue crab, Callinectes sapidus) and prey (the clam, Macoma balthica) patch distribution in large field enclosures in the Rhode River subestuary of the central Chesapeake Bay. The primary objectives were to determine whether predators forage in a way that maximizes prey consumption and to assess how their foraging success is affected by density of conspecifics. We developed a novel ultrasonic telemetry system to observe behavior of individual predators with unprecedented detail. Behavior of predators was more indicative of optimal than of opportunistic foraging. Predators appeared responsive to the overall quality of prey in their habitat. Rather than remaining on a prey patch until depletion, predators appeared to vary their patch use with quality of the surrounding environment. When multiple (two) prey patches were available, residence time of predators on a prey patch was shorter than when only a single prey patch was available. Predators seemed to move among the prey patches fairly regularly, dividing their foraging time between the patches and consuming prey from each of them at a similar rate. That predators more than doubled their consumption of prey when we doubled the number of prey (by adding the second patch) is consistent with optimizing behaviors - rather than with an opportunistic increase in prey consumption brought about simply by the addition of more prey. Predators at high density, however, appeared to interfere with each other's foraging success, reflected by their lower rates of prey consumption. Blue crabs appear to forage more successfully (and their prey to experience higher mortality) in prey patches located within 15-20 meters of neighboring patch, than in isolated patches. Our results are likely to apply, at least qualitatively, to other crustacean-bivalve interactions; including those of commercial interest; their quantitative applicability will depend on the mobility of other predators and the scale of patchiness they perceive. C1 N Carolina State Univ, Dept Marine Earth & Atmospher Sci, Raleigh, NC 27695 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Clark, ME (reprint author), N Carolina State Univ, Dept Marine Earth & Atmospher Sci, Box 8208, Raleigh, NC 27695 USA. EM m_clark@mediwriter.com NR 50 TC 24 Z9 25 U1 3 U2 20 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0906-7590 EI 1600-0587 J9 ECOGRAPHY JI Ecography PD FEB PY 2000 VL 23 IS 1 BP 21 EP 31 DI 10.1034/j.1600-0587.2000.230103.x PG 11 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 295AJ UT WOS:000085943300003 ER PT J AU Pickering, J Read, AF Guerrero, S West, SA AF Pickering, J Read, AF Guerrero, S West, SA TI Sex ratio and virulence in two species of lizard malaria parasites SO EVOLUTIONARY ECOLOGY RESEARCH LA English DT Article DE gametocytes; parasitaemia; Plasmodium; population structure; selfing; virulence ID LOCAL MATE COMPETITION; MIXED-GENOTYPE INFECTIONS; PLASMODIUM-FALCIPARUM; FIG WASPS; POPULATION-STRUCTURE; NEMATODE PARASITES; ANOPHELES-GAMBIAE; BLOOD PARASITES; EVOLUTION; ALLOCATION AB Evolutionary theory predicts that both the virulence and the sex ratio of a parasite can depend upon its population structure, and be positively correlated. With only one or a low number of strains within a host, a low sex ratio and a relatively low virulence are predicted. With high numbers of strains within a host, a more even sex ratio and a high parasite virulence are predicted. We examined gametocyte sex ratio and a possible correlate of virulence, parasite density (parasitaemia), in natural populations of two species causing lizard malaria, Plasmodium 'tropiduri' and P. balli. The mean sex ratios of both species were female-biased, consistent with estimate selfing rates of 0.36 and 0.48 respectively. In P. 'tropiduri', as we predicted, a positive correlation was also observed between our measure of virulence, parasitaemia and the gametocyte sex ratio. Furthermore, the gametocyte sex ratio was positively correlated with gametocyte density (gametocytaemia). This is consistent with facultative sex allocation in response to variable population structure if gametocytaemia is an indicator of the number of clones within a host. These relationships were not observed in I! balli. C1 Univ Edinburgh, Inst Cell Anim & Populat Biol, Edinburgh EH9 3JT, Midlothian, Scotland. Univ Georgia, Inst Ecol, Athens, GA 30602 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP West, SA (reprint author), Univ Edinburgh, Inst Cell Anim & Populat Biol, Edinburgh EH9 3JT, Midlothian, Scotland. RI West, Stuart/M-3608-2014 OI West, Stuart/0000-0003-2152-3153 NR 71 TC 43 Z9 45 U1 1 U2 6 PU EVOLUTIONARY ECOLOGY LTD PI TUCSON PA UNIV ARIZONA, 321 BIOSCIENCES WEST, TUCSON, AZ 85721 USA SN 1522-0613 J9 EVOL ECOL RES JI Evol. Ecol. Res. PD FEB PY 2000 VL 2 IS 2 BP 171 EP 184 PG 14 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 291BL UT WOS:000085713000003 ER PT J AU Wilf, P AF Wilf, P TI Late Paleocene-early Eocene climate changes in southwestern Wyoming: Paleobotanical analysis SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID GREEN RIVER FORMATION; WESTERN NORTH-AMERICA; WILKINS PEAK MEMBER; PLAYA-LAKE COMPLEX; VEGETATIVE MORPHOLOGY; PALEOCLIMATE DATA; ELLESMERE ISLAND; THERMAL MAXIMUM; MIDDLE EOCENE; BIGHORN BASIN AB The warmest global temperatures of the Cenozoic Era occurred in early Eocene time, following a warming trend that started in late Paleocene time, The greater Green River Basin of southwestern Wyoming is one of the best areas in the Rocky Mountains for paleobotanical investigation of the Paleocene-Eocene climatic transition. Intensive sampling has resulted in the recovery of an estimated 189 species of plant macrofossils from the Tiffanian, Clarkforkian, Wasatchian, and Bridgerian land mammal "ages." The leaf morphologies and taxonomic affinities of these fossils were used in combination with other indicators to evaluate Paleocene-Eocene climates, Following cool humid conditions in the Tiffanian, the Clarkforkian was humid and subtropical, and several plant families with modern tropical affinities appeared. However, as in the Tiffanian, Clarkforkian floras had low diversity and were dominated by a single species in the birch family, Mean annual temperature (MAT) rose from an estimated 12 degrees C in the Tiffanian to 19 degrees C in the Clarkforkian, while mean annual precipitation (MAP) for the Tiffanian and Clarkforkian is estimated to have been 130-150 cm, Little fossil plant material is preserved from the latest Clarkforkian or the earliest Wasatchian, which is thought to have contained an interval of cooling and drying followed by renewed warming, By the middle Wasatchian, the time of the Cenozoic thermal maximum, the inferred MAT was about 21 degrees C, and the MAP was near 1-10 cm, A second influx of plant families with tropical affinities appeared in the area, and diversity increased significantly, but most plant families known from the Clarkforkian persisted. Species turnover from the Clarkforkian to the Wasatchian was greater than 80%. A second turnover of more than 80% of species (but not families) from the Wasatchian to the early Bridgerian accompanied drying and increased seasonality of precipitation. The early Bridgerian MAT is inferred to have been near 20 degrees C and the MAP to have been about 80 cm, Except for the Tiffanian and possibly portions of the early Wasatchian, paleoclimates during the study interval were predominantly frost free. Although the moderating influence of the Green River lake system has been suggested as a possible explanation for mild Eocene winters in Wyoming, this study shows that virtually frost-free climates existed in the area prior to and independent of significant lake development. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. RP Wilf, P (reprint author), Univ Michigan, Museum Paleontol, Ann Arbor, MI 48109 USA. EM pwilf@umich.edu NR 123 TC 160 Z9 166 U1 2 U2 22 PU GEOLOGICAL SOC AMER, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD FEB PY 2000 VL 112 IS 2 BP 292 EP 307 DI 10.1130/0016-7606(2000)112<0292:LPEECC>2.3.CO;2 PG 16 WC Geosciences, Multidisciplinary SC Geology GA 281EC UT WOS:000085144100009 ER PT J AU Knowlton, N AF Knowlton, N TI Molecular genetic analyses of species boundaries in the sea SO HYDROBIOLOGIA LA English DT Article; Proceedings Paper CT International Workshop on Marine Genetics CY SEP, 1998 CL RIO JANEIRO, BRAZIL DE sibling species; taxonomy; DNA; electrophoresis; allozymes ID GREAT-BARRIER-REEF; MITOCHONDRIAL-DNA SEQUENCE; HEDISTE DIVERSICOLOR POLYCHAETA; ALGA PHYCODRYS RUBENS; STONE CRABS MENIPPE; POPULATION-STRUCTURE; NORTH-ATLANTIC; NUCLEAR RDNA; EVOLUTIONARY RELATIONSHIPS; ALLOZYME ELECTROPHORESIS AB The tools of molecular genetics have enormous potential for clarifying the nature and age of species boundaries in marine organisms. Below I summarize the genetic implications of various species concepts, and review the results of recent molecular genetic analyses of species boundaries in marine microbes, plants, invertebrates and vertebrates. Excessive lumping, rather than excessive splitting, characterizes the current systematic situation in many groups. Morphologically similar species are often quite distinct genetically, suggesting that conservative systematic traditions or morphological stasis may be involved. Some reproductively isolated taxa exhibit only small levels of genetic differentiation, however. In these cases, large population sizes, slow rates of molecular evolution, and relatively recent origins may contribute to the difficulty in finding fixed genetic markers associated with barriers to gene exchange. The extent to which hybridization blurs species boundaries of marine organisms remains a subject of real disagreement in some groups (e.g. corals). The ages of recently diverged species are largely unknown; many appear to be older than 3 million years, but snails and fishes provide several examples of more recent divergences. Increasingly sophisticated genetic analyses make it easier to distinguish allopatric taxa, but criteria for recognition at the species level are highly inconsistent across studies. Future molecular genetic analyses should help to resolve many of these issues, particularly if coupled with other biological and paleontological approaches. C1 Univ Calif San Diego, Scripps Inst Oceanog, Marine Biol Res Div 0202, La Jolla, CA 92093 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Knowlton, N (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Marine Biol Res Div 0202, La Jolla, CA 92093 USA. NR 223 TC 394 Z9 406 U1 4 U2 67 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD FEB PY 2000 VL 420 BP 73 EP 90 DI 10.1023/A:1003933603879 PG 18 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 305LN UT WOS:000086541700010 ER PT J AU Levison, HF Duncan, MJ Zahnle, K Holman, M Dones, L AF Levison, HF Duncan, MJ Zahnle, K Holman, M Dones, L TI Planetary impact rates from ecliptic comets SO ICARUS LA English DT Article ID JUPITER-FAMILY COMETS; SHORT-PERIOD COMETS; KUIPER BELT; OBJECTS; DISK AB We have reevaluated the impact rates for the planets from ecliptic comets using the integrations in H. Levison and M. Duncan (1997, Icarus 127, 13-32; LD97), We fmd that the current impact rates on the giant planets are actually about four times smaller than LD97's values due to differences in methods of calculating the relevant timescales. The newly calculated impact rates are listed in Table I. However, if the objects leaving the Kuiper belt were primarily on high inclination orbits, then the impact rates on the giant planets are larger than those in Table I by a factor less than or similar to 2. We discuss the dynamics of objects hitting the giant planets in detail, including measurements of the impact velocities. We find that 21% of the objects that hit Jupiter in our simulations were bound to the planet before the impact. The fraction of bound impactors for Saturn is much lower, Jupiter, Saturn, and Uranus have a significant apex-antapex asymmetry for the unbound impactors. (C) 2000 Academic Press. C1 SW Res Inst, Space Studies Dept, Boulder, CO 80302 USA. Queens Univ, Dept Phys, Kingston, ON K7L 3N6, Canada. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Levison, HF (reprint author), SW Res Inst, Space Studies Dept, Boulder, CO 80302 USA. RI Levison, Harold/C-6061-2013 OI Levison, Harold/0000-0001-5847-8099 NR 20 TC 57 Z9 57 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD FEB PY 2000 VL 143 IS 2 BP 415 EP 420 DI 10.1006/icar.1999.6313 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 293JF UT WOS:000085847800018 ER PT J AU Mercader, J Garcia-Heras, M Gonzalez-Alvarez, I AF Mercader, J Garcia-Heras, M Gonzalez-Alvarez, I TI Ceramic tradition in the African forest: Characterisation analysis of ancient and modern pottery from Ituri, D.R.Congo SO JOURNAL OF ARCHAEOLOGICAL SCIENCE LA English DT Article DE D.R. Congo; Ituri; rainforest; pottery; thin section; X.R.D.; hunter-gatherer/farmer interaction ID RAIN-FORESTS; ARCHAEOLOGY AB This paper aims to explain the major characteristics of pottery making in the Ituri rainforest during the last millennium AD by identifying and comparing technological aspects of archaeological and ethnographic assemblages with the primary goal of relating some present features of ceramic production to those of the past. Such comparison has been undertaken by archaeometric characterisation: mineralogical phase analysis, structure identification, and processing behaviour. This study points out that interaction between farmers and hunter-gatherers homogenised the technological repertoires throughout the diverse cultural settings of the N.E. Congo Basin. Recent ceramic assemblages share with ancient ones a consistent distribution and manufacture of pottery across a multiethnic setting in which pottery is used by ethnically diverse slash and burn farmers and bow/net hunter-gatherers. The degree of technological continuity inherent to these assemblages is measurable by empirical means, the results suggesting that ancient and modern traditions have shared, now as then, the five components that make the Ituri pottery tradition insofar as raw material extraction, preparation of clays, modelling, drying, and firing are concerned. C1 George Washington Univ, Dept Anthropol, Washington, DC 20052 USA. Smithsonian Ctr Materials Res & Educ, Suitland, MD 20746 USA. Univ Oviedo, Dept Geol, Asturias, Spain. RP Mercader, J (reprint author), George Washington Univ, Dept Anthropol, Washington, DC 20052 USA. RI Mercader, Julio/G-5182-2010; Garcia-Heras, Manuel/G-8803-2015 NR 56 TC 20 Z9 20 U1 0 U2 6 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0305-4403 J9 J ARCHAEOL SCI JI J. Archaeol. Sci. PD FEB PY 2000 VL 27 IS 2 BP 163 EP 182 DI 10.1006/jasc.1999.0455 PG 20 WC Anthropology; Archaeology; Geosciences, Multidisciplinary SC Anthropology; Archaeology; Geology GA 294NW UT WOS:000085918200007 ER PT J AU Imajo, T Yoshino, K Esmond, JR Parkinson, WH Thorne, AP Murray, JE Learner, RCM Cox, G Cheung, ASC Ito, K Matsui, T AF Imajo, T Yoshino, K Esmond, JR Parkinson, WH Thorne, AP Murray, JE Learner, RCM Cox, G Cheung, ASC Ito, K Matsui, T TI The application of a VUV Fourier transform spectrometer and synchrotron radiation source to measurements of: II. The delta(1,0) band of NO SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HIGH-RESOLUTION; FLUORESCENCE LIFETIMES; OSCILLATOR-STRENGTHS; SOLAR-RADIATION; NITRIC-OXIDE; SPECTROSCOPY; PREDISSOCIATION; PHOTOABSORPTION; OD AB Line-by-line photoabsorption cross-sections of the NO delta(1,0) band were measured with the VUV Fourier transform spectrometer from Imperial College, London, using synchrotron radiation at Photon Factory, KEK, Japan, as a continuum light source. The analysis of the NO delta(1,0) band provides accurate rotational line positions and term values as well as the photoabsorption cross-sections. The molecular constants of the C(1) (2)Pi level are found to be T-0=54 690.155 +/- 0.03 cm(-1), B-v=1.944 06 +/- 0.000 62 cm(-1), D-v=(5.91 +/- 0.42)x10(-5) cm(-1), A(D)=-0.0187 +/- 0.0050 cm(-1), p=-0.0189 +/- 0.0037 cm(-1), and q=-0.015 21 +/- 0.000 20 cm(-1). The sum of the line strengths for all rotational transitions of the NO delta(1,0) band is determined as 4.80x10(-15) cm(2) cm(-1), corresponding to a band oscillator strength of 0.0054 +/- 0.0003. (C) 2000 American Institute of Physics. [S0021-9606(00)00805-9]. C1 Kyushu Univ, Fukuoka 812, Japan. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. Univ Hong Kong, Hong Kong, Hong Kong. KEK, Photon Factory, Tsukuba, Ibaraki 305, Japan. RP Imajo, T (reprint author), Kyushu Univ, Fukuoka 812, Japan. RI Cheung, Allan/D-3059-2009 NR 32 TC 16 Z9 15 U1 1 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 FEB 1 PY 2000 VL 112 IS 5 BP 2251 EP 2257 DI 10.1063/1.480790 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 277NR UT WOS:000084940100023 ER PT J AU Kornicker, LS AF Kornicker, LS TI Will the real fifth limb please stand up (Ostracoda : Cypridinidae)? SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article AB The complexity of the fifth limb of myodocopine Ostracoda has led to many interpretations of its homologies. The presence of muscles interpreted to mark the axis of the endopod of Isocypridina quatuorsetae supports the interpretations by H. J. Hansen and by G. Boxshall contending that the fifth limb of the Cypridinidae bears an unsegmented exopod. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Kornicker, LS (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 15 TC 6 Z9 7 U1 0 U2 0 PU CRUSTACEAN SOC PI SAN ANTONIO PA 840 EAST MULBERRY, SAN ANTONIO, TX 78212 USA SN 0278-0372 J9 J CRUSTACEAN BIOL JI J. Crustac. Biol. PD FEB PY 2000 VL 20 IS 1 BP 195 EP 198 DI 10.1651/0278-0372(2000)020[0195:WTRFLP]2.0.CO;2 PG 4 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 283UU UT WOS:000085295100017 ER PT J AU Strachan, L Panasyuk, AV Dobrzycka, D Kohl, JL Noci, G Gibson, SE Biesecker, DA AF Strachan, L Panasyuk, AV Dobrzycka, D Kohl, JL Noci, G Gibson, SE Biesecker, DA TI Latitudinal dependence of outflow velocities from OVI Doppler dimming observations during the Whole Sun Month SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ULTRAVIOLET CORONAGRAPH SPECTROMETER; SOLAR CORONA; WIND; DISTRIBUTIONS; TEMPERATURE; HYDROGEN AB Empirical determinations of outflow velocities in the solar corona provide a much needed constraint, along with density and temperature determinations, of the acceleration and heating mechanisms in the extended corona. Much progress has been made an density determinations from white light polarized brightness observations but outflow velocities have been more difficult to determine. present the first determinations of outflow velocities versus height and latitude based on a three-dimensional (3-D) reconstruction of the O VI 1032 and 1037 Angstrom emissivities. The Doppler dimming (and pumping) of the local emissivities give true localized outflow velocities at the selected locations in the extended corona from similar to 1.75 to 2.75 solar radii. The velocities are based on an empirical model of the corona which is constrained by the reconstructed O VI emissivities derived from the SOHO Ultraviolet Coronagraph Spectrometer (UVCS) synoptic observations and by electron density determinations based on white light measurements from the SOHO Large Angle Spectroscopic Coronagraph (LASCO) and Mauna Loa Solar Observatory (MLSO) Mk III coronameter. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florence, I-50121 Florence, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Catholic Univ Amer, Washington, DC 20064 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. RP Strachan, L (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Gibson, Sarah/A-9189-2011 NR 31 TC 31 Z9 31 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD FEB 1 PY 2000 VL 105 IS A2 BP 2345 EP 2356 DI 10.1029/1999JA900459 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 281YP UT WOS:000085189300004 ER PT J AU Lieberman, DE Pearson, OM Mowbray, KM AF Lieberman, DE Pearson, OM Mowbray, KM TI Basicranial influence on overall cranial shape SO JOURNAL OF HUMAN EVOLUTION LA English DT Article DE skull; cranium; basicranium; neurocranium; occipital bun; integration ID RELATIVE BRAIN SIZE; VAULT MODIFICATION; EVOLUTIONARY RELATIONSHIPS; NASAL RESISTANCE; FACIAL KYPHOSIS; CENTRAL-EUROPE; HOMO-SAPIENS; GROWTH; BASE; MORPHOLOGY AB This study examines the extent to which the major dimensions of the cranial base (maximum length, maximum breadth, and flexion) interact with brain volume to influence major proportions of the neurocranium and face. A model is presented for developmental interactions that occur during ontogeny between the brain and the cranial base and neurocranium, and between the neurobasicranial complex (NBC) and the face. The model is tested using exocranial and radiographic measurements of adult crania sampled from five geographically and craniometrically diverse populations. The results indicate that while variations in the breadth, length and flexion of the cranial base are mutually independent, only the maximum breadth of the cranial base (POB) has significant effects on overall cranial proportions, largely through its interactions with brain volume which influence NBC breadth. These interactions also have a slight influence on facial shape because NBC width constrains facial width, and because narrow-faced individuals tend to have antero-posteriorly longer faces relative to facial breadth than wide-faced individuals. Finally, the model highlights how integration between the cranial base and the brain may help to account for the developmental basis of some morphological variations such as occipital bunning. Among modern humans, the degree of posterior projection of the occipital bone appears to be a consequence of having a large brain on a relatively narrow cranial base. Occipital buns in Neanderthals, who have wide cranial bases relative to endocranial volume, may not be entirely homologous with the morphology occasionally evident in Homo sapiens. (C) 2000 Academic Press. C1 George Washington Univ, Dept Anthropol, Washington, DC 20052 USA. Smithsonian Inst, Natl Museum Nat Hist, Human Origins Program, Washington, DC 20560 USA. Univ New Mexico, Dept Anthropol, Albuquerque, NM 87131 USA. Amer Museum Nat Hist, Dept Anthropol, New York, NY 10024 USA. RP Lieberman, DE (reprint author), George Washington Univ, Dept Anthropol, 2110 G St NW, Washington, DC 20052 USA. EM danlieb@gwu.edu NR 99 TC 161 Z9 164 U1 2 U2 22 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0047-2484 J9 J HUM EVOL JI J. Hum. Evol. PD FEB PY 2000 VL 38 IS 2 BP 291 EP 315 DI 10.1006/jhev.1999.0335 PG 25 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 294MP UT WOS:000085915300004 PM 10656780 ER PT J AU Ortiz, PE Pardinas, UFJ Steppan, SJ AF Ortiz, PE Pardinas, UFJ Steppan, SJ TI A new fossil Phyllotine (Rodentia : Muridae) from northwestern Argentina and relationships of the Reithrodon group SO JOURNAL OF MAMMALOGY LA English DT Article DE Argentina; paleoenvironment; phylogeny; Pleistocene; sigmodontinae; taxonomy ID SIGMODONTINAE; PLEISTOCENE; CRICETIDAE; EVOLUTION; HISTORY; MUROIDS; RECORD AB We describe an extinct murid, assigned to the tribe Phyllotini, from the late Pleistocene (Tafi del Valle Formation) of La Angostura (26 degrees 55'30 " S, 65 degrees 41'50 " W; 1,900 m elevation) in northwestern Tucuman Province, Argentina. The new genus is characterized by very hypsodont molars with flat crowns and simplified occlusal structure, upper incisors with a mediolateral groove, a straight premaxillary-maxillary suture, and high zygomatic plate with a small spine on its anterodorsal edge. Phylogenetic analyses including fossil and living members of the Reithrodon group show that the new genus is the sister taxon to the Reithrodon-Neotomys-Euneomys clade. The paleoenvironmental and paleogeographic significance of the new genus is discussed within the context of the climatic changes that occurred during the late Pleistocene in southern South America. The new phyllotine would have Lived in high-elevation grasslands, which today occur >1,000 m higher under cold and dry climatic conditions than those of the last glacial maximum. C1 Fac Ciencias Nat, Catedra Paleozool 2, RA-4000 San Miguel De Tucuman, Tucuman, Argentina. Inst Miguel Lillo, RA-4000 San Miguel De Tucuman, Tucuman, Argentina. Museo La Plata, Dept Cient Paleontol Vertebrados, RA-1900 La Plata, Argentina. Smithsonian Museum Support Ctr, Lab Mol Systemat, Suitland, MD 20746 USA. Florida State Univ, Dept Biol Sci, Tallahassee, FL 32306 USA. RP Ortiz, PE (reprint author), Fac Ciencias Nat, Catedra Paleozool 2, Miguel Lillo 205, RA-4000 San Miguel De Tucuman, Tucuman, Argentina. NR 55 TC 18 Z9 23 U1 0 U2 1 PU AMER SOC MAMMALOGISTS PI PROVO PA BRIGHAM YOUNG UNIV, DEPT OF ZOOLOGY, PROVO, UT 84602 USA SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD FEB PY 2000 VL 81 IS 1 BP 37 EP 51 DI 10.1644/1545-1542(2000)081<0037:ANFPRM>2.0.CO;2 PG 15 WC Zoology SC Zoology GA 286GP UT WOS:000085435500003 ER PT J AU Steppan, SJ Sullivan, J AF Steppan, SJ Sullivan, J TI The emerging statistical perspective in systematics: A comment on Mares and Braun SO JOURNAL OF MAMMALOGY LA English DT Article DE Calomys; consistency index; hypothesis testing; nomenclature; phyllotines; statistics; systematics ID PHYLOGENETIC INFERENCE; PHYLLOTINE RODENT; MISSING ENTRIES; SIGMODONTINAE; PARSIMONY; MURIDAE; GENUS AB Recent advances in systematics have resulted in the development of statistical approaches to phylogeny estimation and hypothesis testing. We present this emerging statistical perspective, distinguish it from the nonstatistical approach as commonly practiced, and demonstrate its application to 2 systematic proposals from the recent literature on rodents: Mares and Braun's (1996) retention of Andalgalomys contra Steppan (1995) and the conclusion of Engel et al. (1998) that Calomys is a multitribal composite taxon. Systematic arguments and recommendations by Mares and Braun are critiqued in detail. We argue that the statistical approach provides a more objective and powerful basis for evaluating alternative phylogenetic hypotheses and a more stable foundation for nomenclatural decisions. C1 Smithsonian Inst, Lab Mol Systemat, Suitland, MD 20746 USA. Univ Idaho, Dept Biol Sci, Moscow, ID 83844 USA. RP Steppan, SJ (reprint author), Florida State Univ, Dept Biol Sci, B-157, Tallahassee, FL 32306 USA. EM steppan@bio.fsu.edu RI Rohlf, F/A-8710-2008 NR 27 TC 9 Z9 11 U1 1 U2 1 PU ALLIANCE COMMUNICATIONS GROUP DIVISION ALLEN PRESS PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 USA SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD FEB PY 2000 VL 81 IS 1 BP 260 EP 270 DI 10.1644/1545-1542(2000)081<0260:TESPIS>2.0.CO;2 PG 11 WC Zoology SC Zoology GA 286GP UT WOS:000085435500024 ER PT J AU Newman, LJ Cannon, LRG AF Newman, LJ Cannon, LRG TI A new genus of euryleptid flatworm (Platyhelminthes, Polycladida) from the Indo-Pacific SO JOURNAL OF NATURAL HISTORY LA English DT Article DE Platyhelminthes; Polycladida; Euryleptidae; taxonomy; Great Barrier Reef; Australia AB Five new species and one new combination of marine flatworms belonging to the new genus, Maritigrella nov, gen. (Platyhelminthes, Polycladida, Euryleptidae) are presented here from the Great Barrier Reel, Australia. Additional records are given from Australia, Indonesia and the Republic of the Maldives. C1 Natl Museum Nat Hist, Dept Invertebrate Zool, Smithsonian Inst, Washington, DC 20560 USA. Queensland Museum, S Brisbane, Qld 4101, Australia. RP Newman, LJ (reprint author), Natl Museum Nat Hist, Dept Invertebrate Zool, Smithsonian Inst, Washington, DC 20560 USA. NR 15 TC 10 Z9 12 U1 1 U2 4 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0022-2933 J9 J NAT HIST JI J. Nat. Hist. PD FEB PY 2000 VL 34 IS 2 BP 191 EP 205 DI 10.1080/002229300299606 PG 15 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 274CL UT WOS:000084746100002 ER PT J AU Li, AS Stoecker, DK Coats, DW AF Li, AS Stoecker, DK Coats, DW TI Mixotrophy in Gyrodinium galatheanum (Dinophyceae): Grazing responses to light intensity and inorganic nutrients SO JOURNAL OF PHYCOLOGY LA English DT Article DE feeding responses; light and nutrient limitation; Redfield ratio; mixotrophic dinoflagellate; Gyrodinium galatheanum ID DINOFLAGELLATE GYMNODINIUM-GALATHEANUM; CHEMICAL-COMPOSITION; NITROGEN UPTAKE; CHESAPEAKE BAY; MARINE; PHOSPHORUS; GROWTH; CHRYSOPHYCEAE; INGESTION; PHYTOPLANKTON AB This paper presents results of field and laboratory studies on mixotrophy in the estuarine dinoflagellate Gyrodinium galatheanum (Braarud) Taylor, We tested the hypotheses that this primarily photosynthetic organism becomes phagotrophic when faced with suboptimal light and/or nutrient environments, In Chesapeake Bay, incidence of feeding of this species on cryptophytes is positively correlated with prey density and concentrations of nitrate and nitrite, but negatively correlated with depth, salinity, and phosphate concentration. Feeding in natural assemblages and cultures increased hyperbolically with light intensity, The stoichiometric proportions of dissolved inorganic P and N (DIP:DIN) at the stations where G. galatheanum was present were far below the optimal growth P:N (1:10), Incidence of feeding was negatively related to the ratio of DIP to DIN, suggesting that P limitation may have induced feeding. Addition of nitrate, or addition of both nitrate and phosphate, inhibited feeding in a natural population, indicating that N limitation may also induce feeding, Ingestion of the cryptophyte, Storeatula major, by cultured G, galatheanum was higher in media low in nitrate or phosphate or both, but moderate rates of feeding occurred in nutrient-replete cultures, When cells were grown in media with varying concentrations of nitrate and phosphate, N deficiency resulted in greater cellular N and Chi a losses than did P deficiency, but P deficiency stimulated feeding more than N deficiency, Both N and P deficiency, or P:N ratios that deviated greatly from 1:10, result in an increase of cellular carbon content and an increase in propensity to feed, Our results suggest that feeding in G, galatheanum is partly a strategy for supplementing major nutrients (N and P) that are needed for photosynthetic carbon assimilation, Feeding in G, galatheanum may also be a strategy for supplementing C metabolism or acquiring trace organic growth factors, since feeding occurs, although at a reduced rate, in nutrient-replete cultures. C1 Univ Maryland, Horn Point Lab, Ctr Environm Sci, Cambridge, MD 21613 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Li, AS (reprint author), Woods Hole Oceanog Inst, Dept Biol, Mail Stop 32,Redfield 330, Woods Hole, MA 02543 USA. RI stoecker, diane/F-9341-2013 NR 32 TC 91 Z9 98 U1 4 U2 34 PU PHYCOLOGICAL SOC AMER INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0022-3646 J9 J PHYCOL JI J. Phycol. PD FEB PY 2000 VL 36 IS 1 BP 33 EP 45 DI 10.1046/j.1529-8817.2000.98076.x PG 13 WC Plant Sciences; Marine & Freshwater Biology SC Plant Sciences; Marine & Freshwater Biology GA 294NN UT WOS:000085917500006 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI High art lite: British art in the 1990s. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Libs, Washington, DC USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Libs, Washington, DC USA. NR 1 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 FEB 1 PY 2000 VL 125 IS 2 BP 83 EP 83 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 282DH UT WOS:000085201000074 ER PT J AU Williams, ST AF Williams, ST TI Species boundaries in the starfish genus Linckia SO MARINE BIOLOGY LA English DT Article ID HIGH-DISPERSAL STARFISH; POPULATION-STRUCTURE; GENETIC DIFFERENTIATION; REPRODUCTIVE ISOLATION; MARINE SPECIATION; DNA-SEQUENCE; BIRGUS-LATRO; COCONUT CRAB; PACIFIC; SYSTEMATICS AB The genetic basis for species boundaries in the starfish genus Linckia was examined using variation observed in 613 base pairs (bp) of sequence from the cytochrome oxidase I gene of mtDNA and 16 allozyme loci. Five groups within Linckia were clearly genetically differentiated; L. columbiae, L. bouvieri, two clades within L. guildingi, and one clade with two sub-clades consisting of both L. laevigata and L. multifora. Genetic divergence among these groups is consistent with interspecific variation. The two clades within L. guildingi suggest the presence of a cryptic, partially sympatric, species. Genetic divergence between these two clades implies that they have been genetically distinct from each other for at least one million years. In contrast, genetic data suggest that L. laevigata and L. multifora are a single species, despite the fact that live individuals can be distinguished by their colour and colour pattern, number of madreporites and ratio of arm length to breadth. There are probably three closely related groups within the L. laevigata/L. multifora clade - L. multifora, and two groups in L. laevigata defined by biogeographic province. It is difficult to determine boundaries for these three entities, since genetic and morphological differences are complicated by phenotypic differences arising from both environmental variation and population genetic structure. The difficulties encountered in defining species boundaries in Linckia, particularly with respect to variation arising from the overlap of Indian and Pacific biogeographic provinces, may be a general issue for many marine organisms from this region. C1 Australian Inst Marine Sci, Townsville, Qld 4810, Australia. James Cook Univ N Queensland, Dept Zool & Trop Ecol, Townsville, Qld 4811, Australia. RP Williams, ST (reprint author), Smithsonian Trop Res Inst, Naos Marine Lab, Box 2072, Balboa, Panama. RI Williams, Suzanne/A-9604-2008 OI Williams, Suzanne/0000-0003-2995-5823 NR 63 TC 53 Z9 54 U1 0 U2 7 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD FEB PY 2000 VL 136 IS 1 BP 137 EP 148 DI 10.1007/s002270050016 PG 12 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 295KY UT WOS:000085966300016 ER PT J AU Geller, MJ AF Geller, MJ TI The big picture SO NATURAL HISTORY LA English DT Article C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Geller, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER MUSEUM NAT HISTORY PI NEW YORK PA ATTN: LIBRARY SERIALS UNIT CENTRAL PK WEST AT 79TH ST, NEW YORK, NY 10024-5192 USA SN 0028-0712 J9 NAT HIST JI Nat. Hist. PD FEB PY 2000 VL 109 IS 1 BP 74 EP 76 PG 3 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 277ED UT WOS:000084919000018 ER PT J AU Marsden, BG Griffin, RF AF Marsden, BG Griffin, RF TI The shortest twilight SO OBSERVATORY LA English DT Article C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Marsden, BG (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU OBSERVATORY PI OXFORD PA RUTHERFORD APPLETON LAB, CHILTON DIDCOT,, OXFORD, ENGLAND OX11 OQX SN 0029-7704 J9 OBSERVATORY JI Observatory PD FEB PY 2000 VL 120 IS 1154 BP 62 EP 66 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 288RD UT WOS:000085576300007 ER PT J AU Bahrim, C Thumm, U AF Bahrim, C Thumm, U TI Low-lying P-3(0) and S-3(e) states of Rb-, Cs-, and Fr- SO PHYSICAL REVIEW A LA English DT Article ID ELECTRON-SCATTERING; SHAPE RESONANCES; NEGATIVE-IONS; ATOMS; ENERGIES AB Our Dirac R-matrix calculations suggest that none of the heavy alkali-metal negative ions, Rb, Cs, and Fr, has an excited bound stare. Their lowest excited state appears to be a multiplet of P-3(J)0-shape resonances, the J = 1 component of which was recently observed in photodetachment experiments on Cs-. We analyze these P-3(J)0 and the S-3(e) excited negative ion states in partial and converged total scattering cross sections for slow electrons with incident kinetic energies below 120 meV. Our results are in excellent agreement with available experimental data. We also propose a new value for the electron affinity of Pr, provide the scattering length for electronic collisions with Rb, Cs, and Fr, and discuss the nuclear charge dependence of relativistic effects in the resonance profiles. C1 Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Bahrim, C (reprint author), Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA. NR 22 TC 35 Z9 35 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2000 VL 61 IS 2 AR 022722 DI 10.1103/PhysRevA.61.022722 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 284MV UT WOS:000085336900072 ER PT J AU Derevianko, A Johnson, WR Sadeghpour, HR AF Derevianko, A Johnson, WR Sadeghpour, HR TI Many-body and model-potential calculations of low-energy photoionization parameters for francium SO PHYSICAL REVIEW A LA English DT Article ID ALKALI-METAL ATOMS; PHOTOELECTRON ANGULAR-DISTRIBUTIONS; SPIN-ORBIT; SHIELDING FACTORS; CESIUM; STATE; SHELL; IONS; SUSCEPTIBILITIES; PHOTOABSORPTION AB The photoionization cross section sigma, spin-polarization parameters P and Q, and the angular-distribution asymmetry parameter beta are calculated for the 7s state of francium for photon energies below 10 eV. Two distinct calculations are presented, one based on many-body perturbation theory and another based on the model potential method. Although predictions of the two calculations are similar, the detailed energy dependences of the photoionization parameters from the two calculations differ. From the theoretical p-wave phase shifts, we infer quantum defects for p(1/2) and p(3/2) Rydberg series, permitting us to calculate positions of experimentally unknown p states in francium. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Derevianko, A (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RI Derevianko, Andrei/G-8356-2011 NR 46 TC 6 Z9 7 U1 2 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2000 VL 61 IS 2 AR 022506 DI 10.1103/PhysRevA.61.022506 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 284MV UT WOS:000085336900046 ER PT J AU Oftedal, OT AF Oftedal, OT TI Use of maternal reserves as a lactation strategy in large mammals SO PROCEEDINGS OF THE NUTRITION SOCIETY LA English DT Article; Proceedings Paper CT Summer Meeting of the Nutrition-Society CY JUN 29-JUL 02, 1999 CL UNIV GLASGOW, GLASGOW, SCOTLAND SP Nutr Soc HO UNIV GLASGOW DE lactation; fasting; milk composition; seals; bears; whales ID ANTARCTIC FUR SEALS; HYDROGEN ISOTOPE-DILUTION; BODY-COMPOSITION; HOODED SEAL; ARCTOCEPHALUS-GAZELLA; MILK-COMPOSITION; CYSTOPHORA-CRISTATA; PHOCA-GROENLANDICA; POLAR BEARS; HARBOR SEAL AB The substrate demands of lactation must be met by increased dietary intake or by mobilization of nutrients from tissues. The capacity of animals to rely on stored nutrients depends to a large extent on body size; large animals have greater stores, relative to the demands of lactation, than do small animals. The substrate demands of lactation depend on the composition and amount of milk produced. Animals that fast or feed little during lactation are expected to produce milks low in sugar but high in fat, in order to minimize needs for gluconeogenesis while sustaining energy transfers to the young. The patterns of nutrient transfer are reviewed for four taxonomic groups that fast during part of or throughout lactation: sea lions and fur seals (Carnivora: Otariidae), bears (Carnivora: Ursidae), true seals (Carnivora: Phocidae) and baleen whales (Cetacea: Mysticeti). All these groups produce low-sugar high-fat milks, although the length of lactation, rate of milk production and growth of the young are variable. Milk protein concentrations also tend to be low, if considered in relation to milk energy content. Maternal reserves are heavily exploited for milk production in these taxa. The amounts of lipid transferred to the young represent about one-fifth to one-third of maternal lipid stores; the relative amount of the gross energy of the body transferred in the milk is similar. Some seals and bears also transfer up to 16-18 % of the maternal body protein via milk. Reliance on maternal reserves has allowed some large mammals to give birth and lactate at sites and times far removed from food resources. C1 Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Nutr Labs, Washington, DC 20008 USA. RP Oftedal, OT (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Nutr Labs, Washington, DC 20008 USA. NR 75 TC 78 Z9 79 U1 1 U2 34 PU C A B INTERNATIONAL PI WALLINGFORD PA C/O PUBLISHING DIVISION, WALLINGFORD OX10 8DE, OXON, ENGLAND SN 0029-6651 J9 P NUTR SOC JI Proc. Nutr. Soc. PD FEB PY 2000 VL 59 IS 1 BP 99 EP 106 DI 10.1017/S0029665100000124 PG 8 WC Nutrition & Dietetics SC Nutrition & Dietetics GA 315HQ UT WOS:000087107700012 PM 10828179 ER PT J AU Speelman, LH AF Speelman, LH TI Around the Mall & beyond (The last days of Hsing-Hsing the panda at the National Zoo) SO SMITHSONIAN LA English DT Letter C1 Smithsonian Natl Zool Park, Washington, DC USA. RP Speelman, LH (reprint author), Smithsonian Natl Zool Park, Washington, DC USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SMITHSONIAN ASSOCIATES PI WASHINGTON PA 900 JEFFERSON DRIVE, WASHINGTON, DC 20560 USA SN 0037-7333 J9 SMITHSONIAN JI Smithsonian PD FEB PY 2000 VL 30 IS 11 BP 18 EP 18 PG 1 WC Humanities, Multidisciplinary SC Arts & Humanities - Other Topics GA 277GQ UT WOS:000084924700002 ER PT J AU Dorr, LJ AF Dorr, LJ TI Joseph Andorfer Ewan (1909-1999) - In memoriam SO TAXON LA English DT Biographical-Item C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RP Dorr, LJ (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, MRC-166, Washington, DC 20560 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU INT ASSOC PLANT TAXONOMY PI BERLIN PA BOTANISCHER GARTEN BOTANISCHES MUSEUM BERLIN-DAHLEM, KONIGIN-LUISE-STRABE 6-8, D-14191 BERLIN, GERMANY SN 0040-0262 J9 TAXON JI Taxon PD FEB PY 2000 VL 49 IS 1 BP 107 EP 112 PG 6 WC Plant Sciences; Evolutionary Biology SC Plant Sciences; Evolutionary Biology GA 290EJ UT WOS:000085663000012 ER PT J AU Nicolson, DH AF Nicolson, DH TI Engler Medals presented at the XVI International Botanical Congress in St. Louis SO TAXON LA English DT News Item C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RP Nicolson, DH (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, MRC-166, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT ASSOC PLANT TAXONOMY PI BERLIN PA BOTANISCHER GARTEN BOTANISCHES MUSEUM BERLIN-DAHLEM, KONIGIN-LUISE-STRABE 6-8, D-14191 BERLIN, GERMANY SN 0040-0262 J9 TAXON JI Taxon PD FEB PY 2000 VL 49 IS 1 BP 125 EP 127 PG 3 WC Plant Sciences; Evolutionary Biology SC Plant Sciences; Evolutionary Biology GA 290EJ UT WOS:000085663000014 ER PT J AU Bonne, GP Stimpfle, RM Cohen, RC Voss, PB Perkins, KK Anderson, JG Salawitch, RJ Elkins, JW Dutton, GS Jucks, KW Toon, GC AF Bonne, GP Stimpfle, RM Cohen, RC Voss, PB Perkins, KK Anderson, JG Salawitch, RJ Elkins, JW Dutton, GS Jucks, KW Toon, GC TI An examination of the inorganic chlorine budget in the lower stratosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID UPPER TROPOSPHERE; ER-2 AIRCRAFT; CLONO2; SPECTROMETER; HCL; SPECTROSCOPY; ATMOS; PINATUBO; NITROGEN; AEROSOL AB We use the first simultaneous in situ measurements of ClONO2, ClO, and HCl acquired using the NASA ER-2 aircraft during the Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) mission to test whether these three compounds quantitatively account for total inorganic chlorine (Cl-y) in the lower stratosphere in 1997. We find (ClO + ClONO2 + HCl)/Cl-y = 0.92 +/- 0.10, where Cl-y is inferred from in situ measurements of organic chlorine source gases. These observations are consistent with our current understanding of the budget and partitioning of Cl-y in the lower stratosphere. We find no evidence in support of missing inorganic chlorine species that compose a significant fraction of Cl-y. We apply the analysis to earlier ER-2 observations dating from 1991 to investigate possible causes of previously observed discrepancies in the inorganic chlorine budget. Using space shuttle, satellite, balloon, and aircraft measurements in combination with ER-2 data, we find that the discrepancy is unlikely to have been caused by missing chlorine species or an error in the photolysis rate of chlorine nitrate. We also find that HCl/Cl-y is not significantly controlled by aerosol surface area density in the lower stratosphere. C1 Elect Power Res Inst, Environm Div, Palo Alto, CA 94304 USA. Harvard Univ, Dept Chem & Biol Chem, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bonne, GP (reprint author), Elect Power Res Inst, Environm Div, 3412 Hillview Ave, Palo Alto, CA 94304 USA. EM gbonne@epri.com; stimpfle@harvard.edu; cohen@cchem.berkeley.edu; p_voss@huarp.harvard.edu; kperkins@huarp.harvard.edu; anderson@huarp.harvard.edu; rjs@caesar.jpl.nasa.gov; jelkins@cmdl.noaa.gov; gdutton@cmdl.noaa.gov; jucks@cfa.harvard.edu; toon@mark4sun.jpl.nasa.gov RI Salawitch, Ross/B-4605-2009; Cohen, Ronald/A-8842-2011; Bonne, Gisele/G-3121-2013 OI Salawitch, Ross/0000-0001-8597-5832; Cohen, Ronald/0000-0001-6617-7691; NR 56 TC 25 Z9 25 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JAN 27 PY 2000 VL 105 IS D2 BP 1957 EP 1971 DI 10.1029/1999JD900996 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 280DF UT WOS:000085086400007 ER PT J AU Allen, SW Di Matteo, T Fabian, AC AF Allen, SW Di Matteo, T Fabian, AC TI Hard X-ray emission from elliptical galaxies SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; galaxies : abundances; galaxies : active; galaxies : nuclei; X-rays : galaxies; X-rays : ISM ID ACTIVE GALACTIC NUCLEI; ADVECTION-DOMINATED ACCRETION; MASSIVE BLACK-HOLE; SPECTRAL PROPERTIES; ASCA OBSERVATIONS; RADIO-SOURCES; COLD MATTER; CYGNUS-A; LUMINOSITY; M87 AB We report the detection of hard X-ray emission components in the spectra of six nearby, giant elliptical galaxies observed with the ASCA satellite. The systems studied, which exhibit strong dynamical evidence for supermassive black holes in their nuclei, are M87, NGC 1399 and NGC 4696 (the dominant galaxies of the Virgo, Fornax and Centaurus clusters, respectively) and NGC 4472, 4636 and 4649 (three further giant ellipticals in the Virgo cluster). The ASCA data for all six sources provide clear evidence for hard emission components, which can be parametrized by power-law models with photon indices in the range Gamma=0.6-1.5 (mean value 1.2) and intrinsic 1-10 keV luminosities of 2x10(40)-2x10(42) erg s(-1). Our results imply the identification of a new class of accreting X-ray source, with X-ray spectra significantly harder than those of binary X-ray sources, Seyfert nuclei or low-luminosity active galactic nuclei, and bolometric luminosities relatively dominated by their X-ray emission. We discuss various possible origins for the hard X-ray emission and argue that it is most likely to be due to accretion on to the central supermassive black holes, via low radiative efficiency accretion flows coupled with strong outflows. In the case of M87, our detected power-law flux is in good agreement with a previously reported measurement from ROSAT High Resolution Imager observations, which were able to resolve the jet from the nuclear X-ray emission components. We confirm previous results showing that the use of multiphase models in the analysis of the ASCA data leads to determinations of approximately solar emission-weighted metallicities for the X-ray gas in the galaxies. We also present results on the individual element abundances in NGC 4636. C1 Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Allen, SW (reprint author), Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England. NR 74 TC 55 Z9 55 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JAN 21 PY 2000 VL 311 IS 3 BP 493 EP 506 DI 10.1046/j.1365-8711.2000.03052.x PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 276GK UT WOS:000084867400006 ER PT J AU Di Matteo, T Quataert, E Allen, SW Narayan, R Fabian, AC AF Di Matteo, T Quataert, E Allen, SW Narayan, R Fabian, AC TI Low-radiative-efficiency accretion in the nuclei of elliptical galaxies SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; galaxies : clusters : general; cooling flows; intergalactic medium; galaxies : nuclei; X-rays : galaxies ID ADVECTION-DOMINATED ACCRETION; MASSIVE BLACK-HOLE; GALACTIC NUCLEI; COOLING FLOWS; IONIZED-GAS; RADIO JETS; M87; DISK; LUMINOSITY; SPECTRUM AB The discovery of hard X-ray emission from a sample of six nearby elliptical galaxies, including the dominant galaxies of the Virgo, Fornax and Centaurus clusters (M87, NGC 1399 and NGC 4696, respectively), and NGC 4472, 4636 and 4649 in the Virgo cluster, has important implications for the study of quiescent supermassive black holes. We describe how the broad-band spectral energy distributions for these galaxies, which accrete from their hot gaseous haloes at rates comparable to their Bondi rates, can be explained by low-radiative-efficiency accretion flows in which a significant fraction of the mass, angular momentum and energy is removed from the flows by winds. The observed suppression of the synchrotron components in the radio band (excluding the case of M87) and the systematically hard X-ray spectra, which are interpreted as thermal bremsstrahlung emission, support the conjecture that significant mass outflow is a natural consequence of systems accreting at low radiative efficiencies. We briefly discuss an alternative model for the observed X-ray emission, in which it is due to non-thermal synchrotron-self-Compton processes in the accretion flows, or outflows. This appears to require implausibly weak magnetic fields. Emission from a collimated jet viewed off-axis should be distinguishable from the bremsstrahlung model by variability and thermal line emission studies. We argue that the difference in radiative efficiency between the nuclei of spiral and elliptical galaxies may arise from the different manner in which interstellar gas is fed into the nuclei. In ellipticals, matter fed from the hot (slowly cooling) interstellar medium (ISM) is likely to be highly magnetized and have low specific angular momentum, which favours low-radiative-efficiency accretion solutions and, possibly, the formation of the observed jets. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. RP Di Matteo, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Narayan, Ramesh/0000-0002-1919-2730 NR 72 TC 125 Z9 125 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JAN 21 PY 2000 VL 311 IS 3 BP 507 EP 521 DI 10.1046/j.1365-8711.2000.03134.x PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 276GK UT WOS:000084867400007 ER PT J AU Manmoto, T Kato, S Nakamura, KE Narayan, R AF Manmoto, T Kato, S Nakamura, KE Narayan, R TI Dynamics of the transition from a thin accretion disk to an advection-dominated accretion flow SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; hydrodynamics; turbulence ID SAGITTARIUS-A-ASTERISK; BLACK-HOLE; OPTICALLY THIN; CYGNUS X-1; MODEL; SPECTRUM; LUMINOSITY; QUIESCENCE AB We consider an optically thin advection-dominated accretion flow (ADAF) that is connected at a finite transition radius to an outer optically thick, geometrically thin disk. We include turbulent energy transport and examine ADAF models that satisfy the following boundary conditions at the transition radius: (1) the temperature of the gas is much lower than the virial temperature, (2) the rotation is super-Keplerian, and (3) the net radial flux of energy is outward. We numerically solve the height-integrated viscous hydrodynamic equations with these boundary conditions. We find that the Bernoulli parameter is positive for a wide range of radius, indicating that outflows may be possible from ADAFs. Turbulent energy transport enhances the Bernoulli parameter. We compare our numerical global solutions with two published analytical solutions. We find that the solution of Honma represents the transition region well, while the self-similar solution of Narayan & Yi works better away from the transition. However, neither analytical solution is able to represent the density or angular momentum profile in the inner region of the ADAF, where the flow makes a sonic transition. C1 Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA. Nara Sangyo Univ, Sango, Nara 6308503, Japan. Kyoto Univ, Dept Astron, Sakyo Ku, Kyoto 6068502, Japan. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Manmoto, T (reprint author), Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA. NR 40 TC 33 Z9 34 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2000 VL 529 IS 1 BP 127 EP 137 DI 10.1086/308273 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284LW UT WOS:000085334700014 ER PT J AU Szentgyorgyi, AH Raymond, JC Hester, JJ Curiel, S AF Szentgyorgyi, AH Raymond, JC Hester, JJ Curiel, S TI [Ne v] imaging of the Cygnus Loop SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (Cygnus Loop); ISM : structure; shock waves; ultraviolet : ISM; X-rays : ISM ID HOPKINS-ULTRAVIOLET-TELESCOPE; SHOCK-WAVES; X-RAY; SUPERNOVA REMNANT; PLANETARY-NEBULAE; INTERSTELLAR-MEDIUM; RADIATIVE SHOCKS; FAR-ULTRAVIOLET; EMISSION; DYNAMICS AB We present continuum-subtracted images of a 20' x 20' region of the eastern Cygnus Loop (NGC 6995) in the 3425 Angstrom forbidden line of Ne v. The images reveal bright linear filaments which are associated with, but not positionally coincident with, bright features seen in H alpha, [O III], and other narrowband images. In some areas, the [Ne v] filaments define the edge of X-ray-emitting regions. The filaments exhibit a peak surface brightness of 1.2 x 10(-4) photons cm(-2) s(-1) arcsec(-2) at the top of the atmosphere in images with typical detection limits of similar to 10(-5) photons cm(-2) s(-1) arcsec(-2). We present arguments that these structures are produced by radiative shock waves and discuss implications for the shock velocities and the three-dimensional structure of this section of the Cygnus Loop. We place limits on the importance of thermal conduction-driven evaporation as a contribution to the mass of X-ray-emitting gas. Lack of evidence of [Ne v] emission resulting from thermal evaporation may have significance for supernova remnants and interstellar medium models that rely heavily on the importance of thermal evaporation. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico. RP Szentgyorgyi, AH (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 51 TC 16 Z9 16 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2000 VL 529 IS 1 BP 279 EP 292 DI 10.1086/308237 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284LW UT WOS:000085334700029 ER PT J AU Boroson, B Kallman, T Vrtilek, SD Raymond, J Still, M Bautista, M Quaintrell, H AF Boroson, B Kallman, T Vrtilek, SD Raymond, J Still, M Bautista, M Quaintrell, H TI Hercules X-1: Empirical models of ultraviolet emission lines SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; binaries : eclipsing; line : profiles; stars : individual (Hercules X-1); ultraviolet : stars ID X-RAY BINARIES; COMPTON HEATED WINDS; ACCRETION DISKS; HZ-HERCULIS; PRECESSION; DYNAMICS; CORONAE; ORIGIN; IUE; IV AB The UV emission lines of Hercules X-1, resolved with the Hubble Space Telescope (HST) Goddard High Resolution Spectrograph and Space Telescope Imaging Spectrograph, can be divided into broad (FWHM approximate to 750 km s(-1)) and narrow (FWHM approximate to 150 km s(-1)) components. The broad lines can be unambiguously identified with emission from an accretion disk which rotates prograde with the orbit. The narrow lines, previously identified with the X-ray-illuminated atmosphere of the companion star, are blueshifted at both phi = 0.2 and phi = 0.8, and the line flux at phi = 0.2 is approximate to 0.2 of the flux at phi = 0.8. Line ratio diagnostics show that the density of the narrow-line region is log n(e) = 13.4 +/- 0.2, and T-e = 1.0 +/- 0.2 x 10(5) K. The symmetry of the eclipse ingress suggests that the line emission on the surface of the disk is left-right symmetric relative to the orbit. Model fits to the O v, Si IV, and He II line profiles agree with this result, but fits to the N v lines suggest that the receding side of the disk is brighter. We note that there are narrow absorption components in the N v lines with blueshifts of approximate to 500 km s(-1). C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Open Univ, Milton Keynes MK7 6AA, Bucks, England. RP Boroson, B (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 51 TC 16 Z9 16 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2000 VL 529 IS 1 BP 414 EP 427 DI 10.1086/308272 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284LW UT WOS:000085334700036 ER PT J AU Krennrich, F Le Bohec, S Weekes, TC AF Krennrich, F Le Bohec, S Weekes, TC TI Detection techniques of microsecond gamma-ray bursts using ground-based telescopes SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : observations; instrumentation : detectors; radiation mechanisms : nonthermal ID ACTIVE GALAXY MARKARIAN-421; PRIMORDIAL BLACK-HOLES; HIGH-ENERGY; IMAGING TECHNIQUE; TEV PHOTONS; CRAB-NEBULA; CONSEQUENCES; DISCOVERY; OBJECTS; SEARCH AB Gamma-ray observations above 200 MeV are conventionally made by satellite-based detectors. The EGRET detector on the Compton Gamma Ray Observatory has provided good sensitivity for the detection of bursts lasting for more than 200 ms. Theoretical predictions of high-energy gamma-ray bursts produced by quantum mechanical decay of primordial black holes (Hawking) suggest the emission of bursts on shorter timescales. The final stage of a primordial black hole results in a burst of gamma rays, peaking around 250 MeV and lasting for 1/10 of a microsecond or longer depending on particle physics. In this work we show that there is an observational window using ground-based imaging Cerenkov detectors to measure gamma-ray burst emission at energies E > 200 MeV. This technique, with a sensitivity for bursts lasting nanoseconds to several microseconds, is based on the detection of multiphoton-initiated air showers. C1 Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Krennrich, F (reprint author), Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. NR 35 TC 7 Z9 7 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2000 VL 529 IS 1 BP 506 EP 512 DI 10.1086/308261 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284LW UT WOS:000085334700044 ER PT J AU Ciaravella, A Raymond, JC Thompson, BJ van Ballegooijen, A Strachan, L Li, J Gardner, L O'Neal, R Antonucci, E Kohl, J Noci, G AF Ciaravella, A Raymond, JC Thompson, BJ van Ballegooijen, A Strachan, L Li, J Gardner, L O'Neal, R Antonucci, E Kohl, J Noci, G TI Solar and heliospheric observatory observations of a helical coronal mass ejection SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona; Sun : prominences; Sun : UV radiation ID ERUPTIVE PROMINENCE; SOHO; SPECTROMETER; FLARES; REGION; LASCO; SUN AB The EUV Imaging Telescope (EIT), Large Angle Spectrometric Coronagraph (LASCO), and Ultraviolet Coronagraph Spectrometer (UVCS) instruments aboard the SOHO satellite observed a prominence eruption (coronal mass ejection) on 1997 December 12. Ejected plasma moved at about 130 km s(-1) in the plane of the sky and showed Doppler shifts between -350 and +30 km s(-1). The eruption appeared as a strongly curved arch in EIT images low in the corona. Emission in ions ranging from Si III to O VI in the UVCS spectra indicates a temperature range between 10(4.5) and 10(5.5) K. The morphology of the bright emission regions seen by all three instruments suggests several strands of a helical structure of moderate pitch angle. A reasonable fit to the spatial structure and the velocity evolution measured by UVCS is provided by a left-handed helix untwisting at a rate of about 9 x 10(-4) radians s(-1). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Dipartimento Sci Fis & Astron, I-90134 Palermo, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Osservatorio Astron Torino, I-10125 Pino Torinese, Italy. Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. RP Ciaravella, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Thompson, Barbara/C-9429-2012 NR 43 TC 63 Z9 63 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2000 VL 529 IS 1 BP 575 EP 591 DI 10.1086/308260 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284LW UT WOS:000085334700050 ER PT J AU Ofman, L Romoli, M Poletto, G Noci, G Kohl, JL AF Ofman, L Romoli, M Poletto, G Noci, G Kohl, JL TI UVCSWLC observations of compressional waves in the south polar coronal hole SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; solar wind; Sun : corona; Sun : magnetic fields; waves ID SOLAR-WIND ACCELERATION; SOLITARY WAVES; SPECTROMETER AB Recent SOHO Ultraviolet Coronagraph Spectrometer (UVCS) white light channel (WLC) observations of the south polar coronal hole plumes and interplume regions produce signatures of quasi-periodic variations in the polarized brightness (pB) at a heliocentric distance of 1.9 solar radii (R.). The Fourier power spectrum of the pB time series shows significant peaks at about 1.6-2.5 mHz and additional smaller peaks at longer and shorter timescales. Wavelet analysis of the pB time series shows that the coherence time of the fluctuations is about 30 minutes. The new observations strongly suggest that the fluctuations are compressional wave packets propagating in the coronal hole high above the limb. The presence of compressional waves may have important implications that help to explain the heating of coronal holes and the fast solar wind acceleration. C1 Raytheon ITSS, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Florence, Dept Astron & Space Sci, I-50125 Florence, Italy. Arcetri Observ, I-50125 Florence, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ofman, L (reprint author), Raytheon ITSS, Mail Code 682, Greenbelt, MD 20771 USA. RI Romoli, Marco/H-6859-2012 NR 18 TC 81 Z9 81 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2000 VL 529 IS 1 BP 592 EP 598 DI 10.1086/308252 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284LW UT WOS:000085334700051 ER PT J AU Ball, CD McCarthy, MC Thaddeus, P AF Ball, CD McCarthy, MC Thaddeus, P TI Laboratory detection of a molecular band at lambda 4429 SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : molecules; line : identification; molecular data; molecular processes ID CARBON CHAINS AB A fairly strong molecular absorption band at 4429.27 +/- 0.04 Angstrom, closely centered on the strongest diffuse interstellar band at 4428.9 +/- 1.4 Angstrom, has been found in a supersonic molecular beam among the products of a discharge through benzene and other hydrocarbons. This agreement in wavelength to a few parts in 10(4) strongly suggests a common carrier. The width of the laboratory band is significantly less than that of the diffuse interstellar hand, but this difference may be the result of the very low rotational temperature in the supersonic beam-possibly as low as 2 K-relative to that of a weakly polar molecule in the diffuse interstellar gas (100-200 K). Several candidate carriers are discussed. Two of the more promising are the allyl cation C3H5+ and the dimethylene allenyl radical C5H5, both bent carbon chains that may be close enough to linear to reconcile the puzzling appearance of P-, Q-, and R-branches in the laboratory band with the five hydrogen atoms suggested by the observed deuterium isotopic shifts. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP Ball, CD (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 15 TC 15 Z9 15 U1 1 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2000 VL 529 IS 1 BP L61 EP L64 DI 10.1086/312449 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284LX UT WOS:000085334800016 ER PT J AU Charbonneau, D Brown, TM Latham, DW Mayor, M AF Charbonneau, D Brown, TM Latham, DW Mayor, M TI Detection of planetary transits across a sun-like star SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : eclipsing; planetary systems; stars : individual (HD 209458); techniques : photometric; techniques : radial velocities ID MISSION; KEPLER AB We report high-precision, high-cadence photometric measurements of the star HD 209458, which is known from radial velocity measurements to have a planetary-mass companion in a close orbit. We detect two separate transit events at times that are consistent with the radial velocity measurements. In both cases, the detailed shape of the transit curve due to both the limb darkening of the star and the finite size of the planet is clearly evident. Assuming stellar parameters of 1.1 R. and 1.1 M., we find that the data are best interpreted as a gas giant with a radius of 1.27 +/- 0.02 R-Jup in an orbit with an inclination of 87 degrees 1 +/- 0 degrees 2. We present values for the planetary surface gravity, escape velocity, and average density and discuss the numerous observations that are warranted now that a planet is known to transit the disk of its parent star. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. Observ Geneva, CH-1290 Sauverny, Switzerland. RP Charbonneau, D (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Charbonneau, David/0000-0002-9003-484X NR 20 TC 534 Z9 539 U1 8 U2 26 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2000 VL 529 IS 1 BP L45 EP L48 DI 10.1086/312457 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284LX UT WOS:000085334800012 ER PT J AU Gingerich, O AF Gingerich, O TI Tycho and the ton of gold SO NATURE LA English DT Editorial Material C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gingerich, O (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 20 PY 2000 VL 403 IS 6767 BP 251 EP 251 DI 10.1038/35002212 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 276VU UT WOS:000084899700028 ER PT J AU Balakrishnan, N Jamieson, MJ Dalgarno, A Li, Y Buenker, RJ AF Balakrishnan, N Jamieson, MJ Dalgarno, A Li, Y Buenker, RJ TI Time-dependent quantum mechanical study of photodissociation of molecular oxygen in the Schumann-Runge continuum SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PREDISSOCIATION LINEWIDTHS; ABSORPTION-BANDS; O-2; REGION; O2; NM AB We present a time-dependent quantum mechanical investigation of predissociation of molecular oxygen following absorption in the Schumann-Runge continuum. We calculate the total and partial photoabsorption cross sections in a wave packet formalism in which the predissociation of the B (3)Sigma(u)(-) molecular state is attributed to spin-orbit interactions with the (1)Pi(u), a (3)Pi(u), (5)Pi(u), and 2 (3)Sigma(u)(+) repulsive states. We calculate the branching ratio, describing the relative rates of production of excited (D-1) and ground-state (P-3) oxygen atoms, and find close agreement with a recent measurement. (C) 2000 American Institute of Physics. [S0021-9606(99)00748-5]. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Berg Univ Gesamthsch Wuppertal, Fachbereich Theoret Chem 9, D-42097 Wuppertal, Germany. Univ Glasgow, Dept Comp Sci, Glasgow G12 8QQ, Lanark, Scotland. RP Balakrishnan, N (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 18 TC 15 Z9 15 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 JAN 15 PY 2000 VL 112 IS 3 BP 1255 EP 1259 DI 10.1063/1.480657 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900021 ER PT J AU Murray, S Lung, NP Alvarado, TP Gamble, KC Miller, MA Paglia, DE Montali, RJ AF Murray, S Lung, NP Alvarado, TP Gamble, KC Miller, MA Paglia, DE Montali, RJ TI Idiopathic hemorrhagic vasculopathy syndrome in seven black rhinoceros SO JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION LA English DT Article AB Idiopathic hemorrhagic vasculopathy syndrome (IHVS) was diagnosed in 7 black rhinoceros; this newly described syndrome is characterized by severe body swelling in conjunction with a rapid and profound decrease in Hct. The disorder may be acute or chronic, may recur, and is potentially fatal. Five of the rhinoceros survived an initial episode of IHVS, and 2 of these 5 survived a recurrent episode of IHVS. Two rhinoceros died during treatment of IHVS. Treatment protocols varied, but all 7 rhinoceros received broad-spectrum antibiotics, because an infectious cause was suspected. All rhinoceros also received nonsteroidal anti-inflammatory drugs and supportive care. Idiopathic hemorrhagic vasculopathy syndrome has many similarities to other vasculopathies of domestic animals, such as equine purpura hemorrhagica, but it also appears to have unique identifying features. It has been hypothesized that IHVS may be an immune response to an as yet unidentified infectious agent. Thorough and extensive testing has not identified the potential causative agent, nor the factors that predispose some black rhinoceros to developing IHVS. Further research into the rhinoceros immune system is ongoing and should help elucidate the mechanisms through which IHVS develops.. C1 Ft Worth Zoo, Ft Worth, TX 76110 USA. Dallas Zoo, Dallas, TX 75203 USA. Disneys Anim Kingdom, Lake Buena Vista, FL 32830 USA. Univ Calif Los Angeles, Sch Med, Dept Pathol & Lab Med, Los Angeles, CA 90095 USA. Smithsonian Inst, Natl Zool Pk, Dept Pathol, Washington, DC 20008 USA. RP Murray, S (reprint author), Ft Worth Zoo, Ft Worth, TX 76110 USA. OI Miller, Michele/0000-0002-5883-6076 NR 11 TC 2 Z9 2 U1 1 U2 8 PU AMER VETERINARY MEDICAL ASSOC PI SCHAUMBURG PA 1931 N MEACHAM RD SUITE 100, SCHAUMBURG, IL 60173-4360 USA SN 0003-1488 J9 J AM VET MED ASSOC JI J. Am. Vet. Med. Assoc. PD JAN 15 PY 2000 VL 216 IS 2 BP 230 EP + DI 10.2460/javma.2000.216.230 PG 5 WC Veterinary Sciences SC Veterinary Sciences GA 274RH UT WOS:000084778500029 PM 10649760 ER PT J AU Thumm, U Kurpick, P Wille, U AF Thumm, U Kurpick, P Wille, U TI Size quantization effects in atomic level broadening near thin metallic films SO PHYSICAL REVIEW B LA English DT Article ID HIGHLY-CHARGED IONS; RESONANT ELECTRON-TRANSFER; ULTRATHIN MN FILMS; FIRST-ORDER; SURFACE COLLISIONS; RYDBERG ATOMS; NEUTRALIZATION; SCATTERING; FRONT; HYBRIDIZATION AB The broadening of atomic levels near thin metallic films is studied theoretically within the fixed-atom approximation. First-order level widths are calculated by using a Jennings-type jellium potential to describe the electronic states of the film, and hydrogenic wave functions in parabolic (Stark) representation for the atomic orbitals. In the parabolic representation, hybridization effects due to the long-range image-charge interactions are taken into account. Size quantization in the growth direction of the film gives rise to characteristic structures in level widths, atomic occupation probabilities, and transition distances as a function of the film thickness. Details of this structure depend on the orientation of the Stark orbitals with respect to the film and can be related to the dependence of transition matrix elements on the active electron's wave vector component parallel to the surface for the case of a semi-infinite metal. The large variation of the calculated transition distances with the film thickness may result in observable effects in atomic interactions with thin films. C1 Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Hahn Meitner Inst Berlin GmbH, Bereich Theoret Phys, D-14109 Berlin, Germany. RP Kansas State Univ, Dept Phys, JR Macdonald Lab, Cardwell Hall, Manhattan, KS 66506 USA. OI Thumm, Uwe/0000-0001-9378-6601 NR 36 TC 37 Z9 37 U1 0 U2 0 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 JAN 15 PY 2000 VL 61 IS 4 BP 3067 EP 3077 DI 10.1103/PhysRevB.61.3067 PG 11 WC Physics, Condensed Matter SC Physics GA 284TJ UT WOS:000085348300096 ER PT J AU Kalogera, V Psaltis, D AF Kalogera, V Psaltis, D TI Bounds on neutron-star moments of inertia and the evidence for general relativistic frame dragging SO PHYSICAL REVIEW D LA English DT Article ID QUASI-PERIODIC OSCILLATIONS; X-RAY BINARIES; MILLISECOND PULSAR; MAXIMUM MASS AB Recent x-ray variability observations of accreting neutron stars may provide the first evidence for frame dragging effects around spinning relativistic objects. Motivated by this possibility and its implications for neutron-star structural properties, we calculate new optimal bounds on the masses, radii, and moments of inertia of slowly rotating neutron stars that show kilohertz quasi-periodic oscillations (QPOs). These bounds are derived under minimal assumptions about the properties of matter at high densities and therefore are largely independent of the unknown equation of state. We further derive a semi-analytical upper bound on the neutron-star moment of inertia without making any assumptions about the equation of state of matter at any density. We use this upper bound to show that the maximum possible nodal precession frequency of an inclined circular orbit around a slowly spinning neutron star is nu(NP)similar or equal to 45.2(nu(s)/300 Hz) Hz, where nu(s) is the spin frequency of the neutron star. We conclude that the nodal-precession interpretation of low-frequency QPOs in accreting neutron stars is inconsistent with the beat-frequency interpretation of the kHz QPOs or the identification of the highest-frequency QPO with that of a circular Keplerian orbit in the accretion disk. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kalogera, V (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 47 TC 3 Z9 3 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 EI 1550-2368 J9 PHYS REV D JI Phys. Rev. D PD JAN 15 PY 2000 VL 61 IS 2 AR 024009 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 276BK UT WOS:000084855600033 ER PT J AU Sasselov, DD Lecar, M AF Sasselov, DD Lecar, M TI On the snow line in dusty protoplanetary disks SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; dust, extinction; interplanetary medium; planetary systems; radiative transfer; stars : pre-main-sequence ID T-TAURI STARS; SPECTRAL ENERGY-DISTRIBUTIONS; ACCRETION DISKS; SIZE DISTRIBUTION; YOUNG OBJECTS; SOLAR NEBULA; EVOLUTION; LIMITS; GRAINS AB C. Hayashi prescribed a "minimum-mass solar nebula," which contained just enough material to make the planets. This prescription, which has been widely used in constructing scenarios for planet formation, proposed that ice will condense when the temperature falls below 170 K (the "snow line"). In Hayashi's model, that occurred at 2.7 AU. It is usually assumed that the cores of the giant planets (e.g., Jupiter) form beyond the snow line. The snow line, in Hayashi's model, is where the temperature of a black body that absorbed direct sunlight and reradiated as much as it absorbed would be 170 K. Since Hayashi, there have been a series of more detailed models of the absorption by dust of the stellar radiation and of accretional heating, which alter the location of the snow line. We have attempted a "self-consistent" model of a T Tauri disk in the sense that we used dust properties and calculated surface temperatures that matched observed disks. We then calculated the midplane temperature for those disks, with no accretional heating or with small(less than or equal to 10(-8) M-circle dot yr(-1)) accretion rates. (Larger accretion rates can push the snow line out to beyond 4 AU but do not match the observed disks.) Our models bring the snow line in to the neighborhood of 1 AU-not far enough to explain the close planetary companions to other stars, but much closer than in recent starting lines for orbit migration scenarios. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Sasselov, DD (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 21 TC 102 Z9 102 U1 1 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2000 VL 528 IS 2 BP 995 EP 998 DI 10.1086/308209 PN 1 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282GP UT WOS:000085210100037 ER PT J AU Hughes, JP Rakowski, CE Burrows, DN Slane, PO AF Hughes, JP Rakowski, CE Burrows, DN Slane, PO TI Nucleosynthesis and mixing in Cassiopeia A SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (Cassiopeia A); nuclear reactions, nucleosynthesis, abundances supernova remnants; X-rays : ISM ID A SUPERNOVA REMNANT; X-RAY; ELECTRONS; EMISSION; EJECTA AB We present results from the first light observations of the Cassiopeia A supernova remnant (SNR) by the Chandra X-Ray Observatory. Based on representative spectra from four selected regions, we investigate the processes of nucleosynthesis and mixing in Cas A. We make the first unequivocal identification of iron-rich ejecta produced by explosive silicon burning in a young Galactic SNR. Elsewhere in the remnant, we see silicon rich ejecta from explosive oxygen burning. The Fe-rich ejecta lie outside the Si-rich material, indicating that bulk motions were extensive and energetic enough in Cas A to cause a spatial inversion of a significant portion of the supernova core. It is likely that this inversion was caused by "Fe"-rich ejecta emerging in plumes from the rising bubbles in the neutrino-driven convection layer during the supernova explosion. In addition, the radioactive decay energy from Ni-56 may have contributed to the subsequent evolution of the material. We have also discovered faint, well-defined filaments with featureless X-ray spectra that are possibly sites of cosmic-ray acceleration in Cas A. C1 Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. CEA Saclay, Orme Merisiers, Serv Astrophys, F-91191 Gif Sur Yvette, France. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hughes, JP (reprint author), Rutgers State Univ, Dept Phys & Astron, 136 Frelinghuysen Rd, Piscataway, NJ 08854 USA. NR 19 TC 208 Z9 209 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2000 VL 528 IS 2 BP L109 EP L113 DI 10.1086/312438 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282GW UT WOS:000085210700014 ER PT J AU Raines, SN Watson, DM Pipher, JL Forrest, WJ Greenhouse, MA Satyapal, S Woodward, CE Smith, HA Fischer, J Goetz, JA Frank, A AF Raines, SN Watson, DM Pipher, JL Forrest, WJ Greenhouse, MA Satyapal, S Woodward, CE Smith, HA Fischer, J Goetz, JA Frank, A TI Large proper-motion infrared [Fe II] emission-line features in GGD 37 SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : general; ISM : Herbig-Haro objects; ISM : individual (GGD 37); ISM : jets and outflows; stars : formation ID HERBIG-HARO OBJECTS; STAR-FORMATION REGION; CEPHEUS-A; FORMING REGION; OUTFLOWS; CEP AB We report the detection of proper motions in [Fe Ir] 1.644 mu m emission among the southeasternmost features in the Herbig-Haro object complex GGD 37. Imaging observations were made over a period of 5 yr, at epochs 1993.67, 1996.71, and 1998.68, that reveal proper-motion velocities of 400 +/- 200 km s(-1) at GGD 37:W2 and 850 +/- 200 km s(-1) at a newly identified object, designated GGD 37:RWPF 1. We believe the proper-motion velocity of GGD 37:RWPF 1 is the highest found to date for a Herbig-Haro object. The direction of GGD 37: RWPF 1's proper motion is almost due west, away from the nearby young stellar object complex in Cep A East. GGD 37:W2's direction of proper motion is north/northwest, which does not lead back to any of the compact objects in Cep A East. C1 Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Univ Rochester, CEK Mees Observ, Rochester, NY 14627 USA. Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Wyoming, Wyoming Infrared Observ, Dept Phys & Astron, Laramie, WY 82071 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Coll Wooster, Dept Phys, Wooster, OH 44691 USA. RP Raines, SN (reprint author), Univ Rochester, Dept Phys & Astron, 601 Elmwood Ave, Rochester, NY 14627 USA. NR 35 TC 8 Z9 8 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2000 VL 528 IS 2 BP L115 EP L118 DI 10.1086/312427 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282GW UT WOS:000085210700015 ER PT S AU Gorenstein, P AF Gorenstein, P GP IEEE IEEE TI A generation-X ultra high throughput X-ray astronomy observatory with a new mission architecture SO 2000 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOL 2 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 2000 IEEE Aerospace Conference CY MAR 18-25, 2000 CL BIG SKY, MT SP IEEE, Aerosp & Electr Syst Soc AB The launch of the Chandra X-ray Observatory in June 1999 initiated a new era in X-ray astronomy. The launches of the X-ray Multi-Mirror Observatory by ESA and ASTRO-E by Japan will follow. This new generation of Im class facilities provides astronomers with much better imaging capability, larger collecting power and for the first time, true high resolution spectroscopy. However, most Xray measurements will still be limited by a small number of photons. To probe more deeply into the early universe, at the large distances where dust obscures visible light, we require a future generation ("Generation-X") 30m class telescopes with several orders of magnitude larger collecting area than the above missions or even NASA's next generation Constellation X-ray Mission. However, this cannot be achieved within the architecture of current missions. We describe a new approach based upon formation flying between a large single focus X-ray telescope aboard its own spacecraft and a cluster of smaller spacecraft with detectors and spectrometers, at a quasi-stable point such as the Sun-Earth L2. The telescope mass and volume are too large to be put in space with a single launch. Furthermore we desire that the success of the mission not be dependent upon a single launch. Consequently, the telescope will have to be assembled in situ where humans are not likely to venture. Mirror segments would be delivered over a period of several years and assembled with robotic means. This work was supported was by the NASA Institute of Advanced Concepts. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gorenstein, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS-4, Cambridge, MA 02138 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-5846-5 J9 AEROSP CONF PROC PY 2000 BP 235 EP 242 PG 8 WC Engineering, Aerospace SC Engineering GA BQ98F UT WOS:000165245400023 ER PT S AU Hartmann, L AF Hartmann, L BE Favata, F Kaas, A TI Star formation: Lessons from Taurus SO 33RD ESLAB SYMPOSIUM ON STAR FORMATION FROM THE SMALL TO THE LARGE SCALE SE ESA Special Publications LA English DT Proceedings Paper CT 33rd ESLAB Symposium on Star Formation from the Small to the Large Scale CY NOV 02-05, 1999 CL NOORDWIJK, NETHERLANDS SP ESA Space Sci Dept, ESLAB DE molecular clouds; stars : formation; stars : X-rays ID MAIN-SEQUENCE STARS; AURIGA MOLECULAR CLOUD; ALL-SKY SURVEY; X-RAY SOURCES; STELLAR POPULATION; DARK CLOUDS; AMBIPOLAR DIFFUSION; MAGNETIC-FIELDS; ORION NEBULA; DENSE CORES AB The Taurus molecular cloud complex is the paradigm for quiescent, low-density, isolated star formation. Yet the age distribution of its stellar population indicates that star formation is a rapid and dynamic process, inconsistent with the old picture of magnetically-controlled protostellar cloud collapse. Instead, Taurus seems to have formed stars in a manner qualitatively consistent with the rapid cloud formation and dispersal inferred for other, higher-density star-forming regions. I suggest that the Taurus clouds were formed rapidly by the collision of atomic gas streams ill the interstellar medium, and that star formation ensued immediately afterward. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 42, Cambridge, MA 02138 USA. EM hartmann@cfa.harvard.edu NR 70 TC 7 Z9 7 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-780-1 J9 ESA SPEC PUBL PY 2000 VL 445 BP 107 EP 116 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ93N UT WOS:000165049400013 ER PT S AU Wolk, SJ Adams, NR Drake, J Evans, NR Flaccomio, E Freeman, P Harnden, FR Kashyap, V Patten, BM Pizzolato, N Schachter, J Stauffer, J Zombeck, M Damiani, F Micela, G Sciortino, S Favata, F Jeffries, R AF Wolk, SJ Adams, NR Drake, J Evans, NR Flaccomio, E Freeman, P Harnden, FR Kashyap, V Patten, BM Pizzolato, N Schachter, J Stauffer, J Zombeck, M Damiani, F Micela, G Sciortino, S Favata, F Jeffries, R BE Favata, F Kaas, A TI CHANDRA observations of the open cluster NGC 2516 SO 33RD ESLAB SYMPOSIUM ON STAR FORMATION FROM THE SMALL TO THE LARGE SCALE SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 33rd ESLAB Symposium on Star Formation from the Small to the Large Scale CY NOV 02-05, 1999 CL NOORDWIJK, NETHERLANDS SP ESA Space Sci Dept, ESLAB DE Stars : formation; instrumentation : Chandra, Open Clusters : NGC 2516, X-Rays : general ID NGC-2516 AB We discuss early results of the analysis of CHANDRA images of NGC 2516. This young cluster was observed as Dart of the CHANDRA calibration. We discuss filtering of background data, source detection and source identification. As of this writing, over 150 sources have been found. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Wolk, SJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-780-1 J9 ESA SP PUBL PY 2000 VL 445 BP 559 EP 562 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ93N UT WOS:000165049400103 ER PT J AU Stanek, KZ Kaluzny, J Wysocka, A Thompson, I AF Stanek, KZ Kaluzny, J Wysocka, A Thompson, I TI UBVI color-magnitude diagrams in Baade's Window: Metallicity range, implications for the red clump method, color "anomaly" and the distances to the Galactic center and the Large Magellanic Cloud SO ACTA ASTRONOMICA LA English DT Article DE galaxy : center; galaxies : distances and redshifts; Magellanic Clouds; stars : evolution; stars : horizontal-branch ID GRAVITATIONAL LENSING EXPERIMENT; K-GIANTS; GLOBULAR-CLUSTERS; CCD PHOTOMETRY; ZERO-POINT; STARS; EXTINCTION; SCALE; BULGE; BAR AB We analyze the UBV1 color-magnitude diagrams towards the Galactic bulge in a relatively low-reddening region of Baade's Window. The dereddened red giant branch is very wide [approximate to 1.0 mag in (U - B)(0) and approximate to 0.4 mag in (B - V)(0) and (V - 1)(0)], indicating a significant dispersion of stellar metallicities, which by comparison with the theoretical isochrones and data for Galactic clusters we estimate to lie between approximately -0.7 < [Fe/H] < +0.3, ie., spanning about 1 dex in metallicity, in good agreement with earlier spectroscopic studies. We also discuss the metallicity dependence of the red clump I-band brightness and we show that it is between 0.1-0.2 mag/dex. This agrees well with the previous empirical determinations and the models of stellar evolution. The dereddened (V - 1)(0) color of the red clump in the observed bulge field is ((V - 1)(0))=1.066, sigma((V-1)0) = 0. 14, i.e., 0.056 mag redder than the local stars with good parallaxes measured by Hipparcos. It seems that the large "color anomaly" of approximate to 0.2 mag noticed by Paczynski and Stanek and discussed in many recent papers was mostly due to earlier problems with photometric calibration. When we use our data to re-derive the red clump distance to the Galactic center, we obtain the Galactocentric distance modulus mu(0,GC) = 14.69 +/- 0.1 mag (R-0 = 8.67 +/- 0.4 kpc), with error dominated by the systematics of photometric calibration. We then discuss the systematics of the red clump method and how they affect the red clump distance to the Large Magellanic Cloud. We argue that the value of distance modulus mu(0,LMC) 18.24 +/- 0.08 (44.5 +/- 1.7 kpc), recently refined by Udalski, is currently the most secure and robust of all LMC distance estimates. This has the effect of increasing any LMC-tied Hubble constant by about 12%, including the recent determinations by the HST Key Project and Sandage et al. The UBVI photometry is available through the anonymous ftp service. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. N Copernicus Astron Ctr, PL-00716 Warsaw, Poland. Warsaw Univ Observ, PL-00478 Warsaw, Poland. Carnegie Observ, Pasadena, CA 91101 USA. RP Stanek, KZ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS20, Cambridge, MA 02138 USA. NR 68 TC 30 Z9 31 U1 0 U2 0 PU COPERNICUS FOUNDATION POLISH ASTRONOMY PI WARSAW PA AL UJAZDOWSKIE 4, 00-478 WARSAW, POLAND SN 0001-5237 J9 ACTA ASTRONOM JI Acta Astron. PY 2000 VL 50 IS 2 BP 191 EP 210 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 335QC UT WOS:000088254400003 ER PT S AU Patel, NA AF Patel, NA BE Lewis, H TI Pointing control software for the submillimeter array antennas SO ADVANCED TELESCOPE AND INSTRUMENTATION CONTROL SOFTWARE SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced Telescope and Instrumentation Control Software CY MAR 29-30, 2000 CL MUNICH, GERMANY SP SPIE, DFM Engn Inc, European SO Observ DE pointing; control software; antennas; submillimeter array; SMA ID SYSTEM AB We present the current status of the antenna control software for the Submillimeter array. This software is responsible for pointing and tracking astronomical sources and for antenna pointing calibration. We describe the various stages of the calculations, starting with source-lookup from catalogs and resulting in antenna coordinates commanded to the servo computers. We also present some preliminary results on the painting calibration of the antenna mounts using an optical guide-scope. The control software is distributed among several computers connected by Ethernet and an optic-fiber network known as Reflective Memory. The user interaction is through UNIX-style commands. The scripting language, Perl, is used for automating various tasks while individual commands are directly issued through a shell. We summarize the plans for further work on the control software. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Patel, NA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 78, Cambridge, MA 02138 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3634-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 4009 BP 88 EP 95 DI 10.1117/12.388423 PG 8 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BQ62F UT WOS:000088994500009 ER PT S AU Lukin, MD Hemmer, PR Scully, MO AF Lukin, MD Hemmer, PR Scully, MO BE Bederson, B Walther, H TI Resonant nonlinear optics in phase-coherent media SO ADVANCES IN ATOMIC MOLECULAR, AND OPTICAL PHYSICS, VOL. 42 SE Advances In Atomic Molecular and Optical Physics LA English DT Review ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; DOUBLE-LAMBDA-SCHEME; POPULATION-INVERSION; ATOMIC COHERENCE; QUANTUM COHERENCE; DISPERSIVE PROPERTIES; LASER OSCILLATION; SELF-OSCILLATION; RUBIDIUM ATOMS; SODIUM VAPOR C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. NR 88 TC 179 Z9 181 U1 1 U2 14 PU ELSEVIER ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 1049-250X BN 0-12-003842-0 J9 ADV ATOM MOL OPT PHY JI Adv. Atom. Mol. Opt. Phys. PY 2000 VL 42 BP 347 EP 386 DI 10.1016/S1049-250X(08)60190-1 PG 40 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA BP57T UT WOS:000085557900008 ER PT B AU Correll, DL Jordan, TE Weller, DE AF Correll, DL Jordan, TE Weller, DE BE Sharpley, AN TI Transfer of phosphorus from the farm to the bay SO AGRICULTURE AND PHOSPHORUS MANAGEMENT: THE CHESAPEAKE BAY LA English DT Proceedings Paper CT Conference on Agriculture and Phosphorus Management - The Chesapeake Bay CY APR, 1998 CL PENN STATE UNIV, UNIVERSITY PK, PA SP Sci & Techn Advisory Comm, Chesapeake Bay Program HO PENN STATE UNIV ID RIPARIAN FOREST; CHESAPEAKE BAY; LAND-USE; DISCHARGES; WATERSHEDS; NUTRIENTS; RIVER; AGRICULTURE; ESTUARY AB Phosphorus is a key element related to the eutrophication of Chesapeake Bay. Farm fields are a major source of phosphorus in land discharges. Most of the phosphorus is transported from fields to the receiving waters via overland flows during storm events, particularly in wet seasons of the years. The flux of total phosphorus from Rhode River cropland was 58, 1350, and 10,800 g P ha(-1) in very dry, average precipitation, and very wet years, respectively. Almost all of the phosphorus transported in storm events is particulate organic phosphorus and particulate inorganic phosphorus. Some of this phosphorus is released as dissolved inorganic phosphate after entering the Chesapeake. The integrated mean particulate phosphorus concentrations during storm events were directly correlated with peak water discharge during the storms. Increased fluxes of phosphorus in wet periods were due to both higher water discharges and higher phosphorus concentrations, especially in the spring. Rhode River watershed fluxes of phosphorus were higher in general than those we measured in other parts of the Coastal Plain and Piedmont. Riparian buffers will only intercept large amounts of phosphorus from overland storm flows if they are managed to prevent concentrated flows during storms. Reservoirs have a major impact on the transport of both particulate and dissolved forms of phosphorus. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Correll, DL (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. NR 20 TC 3 Z9 3 U1 1 U2 4 PU LEWIS PUBLISHERS INC PI BOCA RATON PA 2000 CORPORATE BLVD NW, BOCA RATON, FL 33431 USA BN 1-56670-494-4 PY 2000 BP 131 EP 142 PG 12 WC Agronomy; Environmental Sciences; Water Resources SC Agriculture; Environmental Sciences & Ecology; Water Resources GA BP67W UT WOS:000085842300009 ER PT B AU Kannappan, S AF Kannappan, S BE Percy, JR Wilson, JB TI A survey of amateur & professional participants in the Variable Star Observing Partnership SO AMATEUR - PROFESSIONAL PARTNERSHIPS IN ASTRONOMY, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on Amateur - Professional Partnerships in Astronomical Research and Education CY JUL 05-07, 1999 CL UNIV TORONTO, TORONTO, CANADA SP Canadian Space Agcy, Natl Aeronaut & Spacy Agcy, Natl Sci Fdn, Univ Toronto, Off Res & Int Relat, Univ Toronto, Dept Astronomy, Univ Toronto, Dept Phys, Univ Toronto, Erindale Campus, Astron Soc Pacific, Royal Astron Soc Canada, Amer Assoc Variable Star Observers HO UNIV TORONTO C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kannappan, S (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-052-8 J9 ASTR SOC P PY 2000 VL 220 BP 29 EP 31 PG 3 WC Astronomy & Astrophysics; Education, Scientific Disciplines SC Astronomy & Astrophysics; Education & Educational Research GA BR94B UT WOS:000168123500007 ER PT J AU Grissom, CA AF Grissom, CA TI Neolithic statues for Ain Ghazal: Construction and form SO AMERICAN JOURNAL OF ARCHAEOLOGY LA English DT Article ID JORDAN AB Reassembly of five large lime plaster statues from the seventh millennium BC following their excavation in 1985 at Ain Ghazal, Jordan, provided an opportunity to examine evidence of their construction. For the most part, the statues had lain horizontally during fabrication, and they were made in stages by applying plaster to reed bundles bound with cordage. Full-scale replication of a bust and a figure provided additional information about construction. Plaster probably has to be applied while armatures were horizontal because of the statues' large size; broad, flat, and simple forms were made a sa consequence. In order to fashion the complex standing figures, legs were modeled separately and joined to the rest of the statue with plaster. Statues may have been accessorized with wigs, clothing, on other materials to simulate human appearance. C1 Smithsonian Inst, Ctr Materials Res & Educ, Suitland, MD 20746 USA. RP Grissom, CA (reprint author), Smithsonian Inst, Ctr Materials Res & Educ, 4210 Silver Rd, Suitland, MD 20746 USA. NR 27 TC 10 Z9 10 U1 2 U2 7 PU ARCHAEOLOGICAL INST PI NEW YORK PA 135 WILLIAM ST, NEW YORK, NY 10038-3805 USA SN 0002-9114 J9 AM J ARCHAEOL JI Am. J. Archaeol. PD JAN PY 2000 VL 104 IS 1 BP 25 EP 45 DI 10.2307/506791 PG 21 WC Archaeology SC Archaeology GA 430RT UT WOS:000168589900003 ER PT J AU Kolman, CJ Tuross, N AF Kolman, CJ Tuross, N TI Ancient DNA analysis of human populations SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Article DE aDNA; mitochondrial DNA; PCR contamination; New World ID HUMAN MITOCHONDRIAL-DNA; NEW-WORLD; NUCLEAR-DNA; AMPLIFICATION; PCR; SEQUENCE; MTDNA; DIVERSITY; ORIGIN; EXTRACTION AB The use of ancient DNA (aDNA) in the reconstruction of population origins and evolution is becoming increasingly common. The resultant increase in number of samples and polymorphic sites assayed and the number of studies published may give the impression that all technological hurdles associated with aDNA technology have been overcome. However, analysis of aDNA is still plagued by two issues that emerged at the advent of aDNA technology, namely the inability to amplify a significant number of samples and the contamination of samples with modern DNA. Herein, we analyze five well-preserved skeletal specimens from the western United States dating from 800-1600 A.D. These specimens yielded DNA samples with levels of contamination ranging from 0-100%, as determined by the presence or absence of New World-specific mitochondrial markers. All samples were analyzed by a variety of protocols intended to assay genetic variability and detect contamination, including amplification of variously sized DNA targets, direct DNA sequence analysis of amplification products and sequence analysis of cloned amplification products, analysis of restriction fragment length polymorphisms, quantitation of target DNA, amino acid racemization, and amino acid quantitation. Only the determination of DNA sequence from a cloned amplification product clearly revealed the presence of both ancient DNA and contaminating DNA in the same extract. Our results demonstrate that the analysis of aDNA is still an excruciatingly slow and meticulous process. All experiments, including stringent quality and contamination controls, must be performed in an environment as free as possible of potential sources of contaminating DNA, including modern DNA extracts. Careful selection of polymorphic markers capable of discriminating between ancient DNA and probable DNA contaminants is critical. Research strategies must be designed with a goal of identifying all DNA contaminants in order to differentiate convincingly between contamination and endogenous DNA. (C) 2000 Wiley-Liss, Inc. C1 Smithsonian Ctr Mat Res & Educ, Suitland, MD 20746 USA. RP Kolman, CJ (reprint author), NIAAA, NIH, LNG, 12420 Parklawn Dr,Pk Bldg,Room 451, Rockville, MD 20852 USA. NR 44 TC 109 Z9 112 U1 0 U2 13 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PD JAN PY 2000 VL 111 IS 1 BP 5 EP 23 PG 19 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 273NK UT WOS:000084713600002 PM 10618586 ER PT J AU Gordon, KD Coppa, A AF Gordon, KD Coppa, A TI Unusual non-occlusal dental wear facets in prehistoric Sudanese. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, Washington, DC 20560 USA. Univ La Sapienza, Sez Antropol, Dipartimento BAU, I-00185 Rome, Italy. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 2000 SU 30 BP 163 EP 163 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 286RJ UT WOS:000085458900202 ER PT J AU Mulhern, DM Ubelaker, DH AF Mulhern, DM Ubelaker, DH TI Differences in osteon organization between human and nonhuman bone. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 2000 SU 30 BP 233 EP 234 PG 2 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 286RJ UT WOS:000085458900396 ER PT J AU Ousley, S Owsley, D Mulhern, D AF Ousley, S Owsley, D Mulhern, D TI Lost and found in the museum: Repatriation, ancestry, ethnicity, and history. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Smithsonian Inst, Dept Anthropol, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 2000 SU 30 BP 243 EP 243 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 286RJ UT WOS:000085458900424 ER PT J AU Sanz, C Monfort, S Fouts, R AF Sanz, C Monfort, S Fouts, R TI Fecal testosterone and corticosterone levels and behavioral correlates in a group of five captive chimpanzees (Pan troglodytes). SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Washington Univ, St Louis, MO 63130 USA. Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. Cent Washington Univ, Chimpanzee & Human Commun Inst, Ellensburg, WA 98926 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 2000 SU 30 BP 268 EP 268 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 286RJ UT WOS:000085458900492 ER PT J AU Schwartz, GT Dean, C AF Schwartz, GT Dean, C TI The ontogeny of canine dimorphism in extant hominoids. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 George Washington Univ, Washington, DC USA. Smithsonian Inst, NMNH, Human Origins Program, Washington, DC 20560 USA. UCL, Evolutionary Anat Unit, London, England. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 2000 SU 30 BP 275 EP 275 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 286RJ UT WOS:000085458900512 ER PT J AU Wiltschke-Schrotta, K Ubelaker, DH AF Wiltschke-Schrotta, K Ubelaker, DH TI Human remains on display - Curatorial and cultural concerns. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Museum Hist Nat, Dept Archeol Biol & Anthropol, A-1014 Vienna, Austria. Smithsonian Inst, Natl Museum Amer Hist, Dept Anthropol, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 2000 SU 30 BP 324 EP 324 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 286RJ UT WOS:000085458900649 ER PT J AU Nam, VS Yen, NT Holynska, M Reid, JW Kay, BH AF Nam, VS Yen, NT Holynska, M Reid, JW Kay, BH TI National progress in dengue vector control in Vietnam: Survey for Mesocyclops (Copepoda), Micronecta (Corixidae), and fish as biological control agents SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID AEDES-AEGYPTI; CYCLOPIDAE AB This paper describes the process of expanding a successful dengue control program in 3 provinces in northern Vietnam into a national one and demonstrates the presence of a rich, low-cost resource that could have similar applicability to other countries in the region. The cornerstone of the preventive strategy is larval control of Aedes aegypti (L.), the major vector, using predators such as copepods, Mesocyclops spp., aided by the corixid bug Micronecta quadrishigata Bredd, and fish in large water storage containers. From 1989 to 1998, 9 species of Mesocyclops (M. woutersi Van de Velde, M. aspericornis (Daday), M. ruttneri Kiefer, M. thermocyclopoides Harada, M. affinis Van de Velde, M. ogunnus Onabamiro, M. yenae Holynska, M. cf. pehpeiensis Hu, and M. dissimilis Defaye and Kawabata) were found in natural and artificial habitats in 26 provinces throughout Vietnam. The predatory capacities of 6 of these were evaluated in the laboratory. This indicated that daily consumption/killing averaged between 16 and 41 Ae. aegypti larvae per copepod. From detailed evaluations in 9 provinces, Mesocyclops spp. were surprisingly common in 8,413 artificial containers (concrete tanks, wells, ornamental ponds and in the south, large jars). Because of existing practices for washing and water transfer from ponds and lakes in Ha Tay and Ha Bac, Mesocyclops spp. already occurred in 60-100% of the water storage containers. When the relationship between the presence or absence of Mesocyclops and Aedes larvae in 5,111 containers was analyzed by the chi-square test, their distributions were significantly related, indicating control (odds ratio = 0.56). When 3,426 containers that did not contain Mesocyclops or fish were analyzed in relation to the distribution of Aedes larvae, those with Micronecta also had significantly less Aedes (odds ratio = 0.43). Therefore, this study demonstrates that there is an abundance of local Mesocyclops spp. in Vietnam that can be incorporated into specifically designed community-based control programs aided by Micronecta and fish. C1 Univ Queensland, Queensland Inst Med Res, Trop Hlth Program,Mosquito Control Lab, Australian Ctr Int & Trop Hlth & Nutr, Brisbane, Qld 4029, Australia. Natl Inst Hyg & Epidemiol, Hanoi 10000, Vietnam. Polish Acad Sci, Museum & Inst Zool, PL-00679 Warsaw, Poland. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Kay, BH (reprint author), Univ Queensland, Queensland Inst Med Res, Trop Hlth Program,Mosquito Control Lab, Australian Ctr Int & Trop Hlth & Nutr, PO Royal Brisbane Hosp, Brisbane, Qld 4029, Australia. NR 14 TC 48 Z9 54 U1 0 U2 8 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 JAN PY 2000 VL 62 IS 1 BP 5 EP 10 PG 6 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA 298NF UT WOS:000086145500005 PM 10761718 ER PT J AU Ni, YX Post, JE Hughes, JM AF Ni, YX Post, JE Hughes, JM TI The crystal structure of parisite-(Ce), Ce2CaF2(CO3)(3) SO AMERICAN MINERALOGIST LA English DT Article ID ATOMIC ARRANGEMENT; SYNCHYSITE-(CE) AB The crystal structure of parisite-(Ce) was solved and refined to R = 0.044, Rw = 0.037 using three-dimensional X-ray diffraction data (XRD). In contrast to the putative hexagonal cell, weak XRD maxima on precession films demonstrate that the parisite-(Ce) is monoclinic with a space group C2/c Or CC. The unit cell was refined as a = 12.305(2), b = 7.1053(5), c = 28.250(5) Angstrom, and beta = 98.257(14)degrees The structure refinement confirmed the space group Cc. Like bastnasite and synchysite, parisite possesses a (001) layer structure, with layers of (Ca) and (CeF) separated by layers of carbonate groups. The [001] layer stacking sequence is... (Ca), (CO3), (CeF), (CO3), (CeF), (CO3), (Ca), (CO3), (CeF), (CO3), (CeF), (CO3).... The parisite-(Ce) structure can be considered as two portions of the bastnasite structure connected by a (Ca) layer. The insertion of a (Ca) layer would create long [001]*: structure voids in the F columns if the bastnasite portions stacked hexagonally; therefore, the two bastnasite portions are offset along [(1) over bar 10] by a/6(sin60 degrees) (or [(1) over bar 00] in hexagonal cells, by a/3) such that the oxygen atoms of the vertical edges of the carbonate groups occupy the voids. Polytypism results because a bastnasite portion can shift equally in two possible directions, +/-120 degrees from the previous offset vector. The parisite-(Ce) structure elucidated herein is the simplest and most common polytype possible. 2M. The polytype 6R, which was previously believed to be the most common, has not been found during our extensive study. C1 Smithsonian Inst, Dept Mineral Sci, Washington, DC 20560 USA. Miami Univ, Dept Geol, Oxford, OH 45056 USA. RP Ni, YX (reprint author), Smithsonian Inst, Dept Mineral Sci, NHB-119, Washington, DC 20560 USA. NR 15 TC 19 Z9 19 U1 1 U2 4 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 JAN PY 2000 VL 85 IS 1 BP 251 EP 258 PG 8 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 273NP UT WOS:000084714000026 ER PT J AU Heyer, WR de Carvalho, CM AF Heyer, WR de Carvalho, CM TI The enigmatic advertisement call of Eleutherodactylus ramagii (Amphibia : Anura : Leptodactylidae) SO AMPHIBIA-REPTILIA LA English DT Article C1 Smithsonian Inst, Natl Museum Amer Hist, Div Amphibians & Reptiles, Washington, DC 20560 USA. Univ Fed Sergipe, Dept Biol, BR-49100000 Sao Cristovao, SE, Brazil. RP Heyer, WR (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Div Amphibians & Reptiles, MRC 162, Washington, DC 20560 USA. NR 9 TC 1 Z9 1 U1 1 U2 1 PU BRILL ACADEMIC PUBLISHERS PI LEIDEN PA PLANTIJNSTRAAT 2, P O BOX 9000, 2300 PA LEIDEN, NETHERLANDS SN 0173-5373 J9 AMPHIBIA-REPTILIA JI Amphib. Reptil. PY 2000 VL 21 IS 1 BP 117 EP 121 PG 5 WC Zoology SC Zoology GA 307GH UT WOS:000086644700010 ER PT J AU Wagner, DL Loose, JL Fitzgerald, TD De Benedictis, JA Davis, DR AF Wagner, DL Loose, JL Fitzgerald, TD De Benedictis, JA Davis, DR TI A hidden past: the hypermetamorphic development of Marmara arbutiella (Lepidoptera : Gracillariidae) SO ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA LA English DT Article DE Marmara arbutiella; Mirax; phylogenetic constraint; developmental constraint; leaf miner; hypermetamorphosis AB Development in Marmara arbutiella Busck is hypermetamorphic, with 3 behaviorally and morphologically distinct larval forms. There are 6-8 sag-feeding and 2, nonfeeding, structurally differentiated instars. The early instars are legless, dorsoventrally compressed, prognathous sap feeders. The Ist of the nonfeeding instars, which we call the transition instar, never issues from the cuticle of the previous (feeding) instar; instead there is apolysis without ecdysis. It is characterized by reduction-the cuticle is transparent, the feeding structures are nonfunctional, and the legs are vestigial. Moreover, the stadium is ephemeral, lasting no less than or equal to 24 h. The 2nd nonfeeding stage is a fully legged and ambulatory instar, with rudimentary feeding structures and a functional spinneret. Upon issuing from the mine, this instar spins a cocoon that is elaborately decorated with clusters of 31-114 pearly bubbles that are extruded from its anus and then individually attached to the exterior of the cocoon. We contrast the unique development of Marmara with other gracillarids and interpret the transition instar as an ontogenetic bridge, a stage of risk and metabolic cost without function. C1 Univ Connecticut, Dept Ecol & Evolutionary Biol, Storrs, CT 06269 USA. SUNY Coll Cortland, Dept Biol, Cortland, NY 13045 USA. Univ Calif Davis, Dept Entomol, Davis, CA 95616 USA. Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Wagner, DL (reprint author), Univ Connecticut, Dept Ecol & Evolutionary Biol, Storrs, CT 06269 USA. NR 18 TC 18 Z9 18 U1 0 U2 3 PU ENTOMOL SOC AMER PI LANHAM PA 9301 ANNAPOLIS RD, LANHAM, MD 20706 USA SN 0013-8746 J9 ANN ENTOMOL SOC AM JI Ann. Entomol. Soc. Am. PD JAN PY 2000 VL 93 IS 1 BP 59 EP 64 DI 10.1603/0013-8746(2000)093[0059:AHPTHD]2.0.CO;2 PG 6 WC Entomology SC Entomology GA 359UZ UT WOS:000089631600008 ER PT J AU Karol, KG Suh, YB Schatz, GE Zimmer, EA AF Karol, KG Suh, YB Schatz, GE Zimmer, EA TI Molecular evidence for the phylogenetic position of Takhtajania in the Winteraceae: Inference from nuclear ribosomal and chloroplast gene spacer sequences SO ANNALS OF THE MISSOURI BOTANICAL GARDEN LA English DT Article DE Canellaceae; combined data; cpDNA; ITS; likelihood; phylogeny; Takhtajania; Winteraceae ID NUCLEOTIDE-SEQUENCES; DNA-SEQUENCES; CONFIDENCE-LIMITS; NONCODING REGIONS; SUBSTITUTION; RBCL; BOOTSTRAP; EVOLUTION; TREES AB The nucleotide sequences of the internal transcribed spacers (ITS 1 and ITS 2) and 5.8S coding region of nuclear ribosomal DNA, as well as the non-coding trnL-trnF spacer regions of the chloroplast DNA, were determined and analyzed to estimate the phylogenetic position of Takhtajania perrieri (Capuron) Baranova & J.-F. Leroy within the Winteraceae. Using representatives of each genus of Canellaceae as outgroups (Canella, Capsicodendron, Cinnamodendron, Cinnamosma, Pleodendron, and Warburgia), bath maximum parsimony and maximum likelihood analyses place Takhtajania in a basal position sister to the remainder of the Winteraceae. Although the overall topology within the Winteraceae was mostly congruent between nuclear and chloroplast data sets, the trnL-trnF data resulted in lower support values in comparison to the ITS data, and failed to resolve basal relationships in the family, yielding alternative equally parsimonious solutions. The combined nuclear/chloroplast data set resulted in a single tree identical to that generated by nuclear data alone, but demonstrated strengthened support for a basal branch lending to Takhtajania, as well as for the position of Tasmannia as the next branch within the family. Potentially conflicting signals from nuclear and chloroplast data indicate that further taxon sampling or additional sequence data may be required to infer infra-familial phylogenetic relationships for Canellaceae. C1 Natl Museum Nat Hist, Smithsonian Inst, Lab Mol Syst, Washington, DC 20560 USA. Seoul Natl Univ, Inst Nat Prod Res, Seoul 110460, South Korea. Missouri Bot Garden, St Louis, MO 63166 USA. RP Karol, KG (reprint author), Univ Maryland, Dept Mol Genet & Cell Biol, College Pk, MD 20742 USA. RI Zimmer, Elizabeth/G-3890-2011 NR 53 TC 43 Z9 44 U1 1 U2 2 PU MISSOURI BOTANICAL GARDEN PI ST LOUIS PA 2345 TOWER GROVE AVENUE, ST LOUIS, MO 63110 USA SN 0026-6493 J9 ANN MO BOT GARD JI Ann. Mo. Bot. Gard. PY 2000 VL 87 IS 3 BP 414 EP 432 DI 10.2307/2666200 PG 19 WC Plant Sciences SC Plant Sciences GA 364QE UT WOS:000089902600012 ER PT J AU Bowyer, S Drake, JJ Vennes, S AF Bowyer, S Drake, JJ Vennes, S TI Extreme ultraviolet astronomy SO ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS LA English DT Review DE planets; interstellar medium; stars; extragalactic ID DA WHITE-DWARFS; LOCAL INTERSTELLAR-MEDIUM; ALL-SKY SURVEY; WIDE-FIELD CAMERA; LATE-TYPE STARS; X-RAY-EMISSION; STELLAR CORONAL ABUNDANCES; CANUM-VENATICORUM BINARIES; EPSILON-CANIS-MAJORIS; RIGHT-ANGLE PROGRAM AB Astronomical studies in the extreme ultraviolet (EW) band of the spectrum were dismissed during the early years of space astronomy as impossible, primarily because of the mistaken view that radiation in this band would be absorbed by the interstellar medium. Observations in the 1980s from sounding rockets and limited duration orbital spacecraft began to show the potential of this field and led to the deployment of two spacecraft devoted to EUV astronomy: the UK Wide Field Camera and the Extreme Ultraviolet Explorer. The instrumentation in these missions, although quite limited in comparison with instrumentation in other fields of space astronomy, provided unique and far-reaching results. These included new information on solar system topics, stellar chromospheres and corona, white dwarf astrophysics, cataclysmic variables, the interstellar medium, galaxies, and clusters of galaxies. We summarize these findings herein. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Australian Natl Univ, Sch Math Sci, Astrophys Theory Ctr, Canberra, ACT 0200, Australia. RP Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. EM bowyer@ssl.berkeley.edu; jdrake@cfa.harvard.edu; vennes@wintermute.anu.edu.au RI Vennes, Stephane/G-9903-2014 NR 346 TC 34 Z9 34 U1 1 U2 1 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0066-4146 J9 ANNU REV ASTRON ASTR JI Annu. Rev. Astron. Astrophys. PY 2000 VL 38 BP 231 EP 288 DI 10.1146/annurev.astro.38.1.231 PG 58 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 385NV UT WOS:000166011300008 ER PT J AU Ruiz, GM Fofonoff, PW Carlton, JT Wonham, MJ Hines, AH AF Ruiz, GM Fofonoff, PW Carlton, JT Wonham, MJ Hines, AH TI Invasion of coastal marine communities in North America: Apparent patterns, processes, and biases SO ANNUAL REVIEW OF ECOLOGY AND SYSTEMATICS LA English DT Review DE nonindigenous; invasion resistance; disturbance; propagule supply; introduced species ID SYNIDOTEA-LAEVIDORSALIS MIERS; BALLAST WATER; BIOLOGICAL INVASIONS; TRANSPORT; ECOLOGY; ECOSYSTEM; INTRODUCTIONS; INVASIBILITY; RESISTANCE; CALIFORNIA AB Biological invasions of marine habitats have been common, and many patterns emerge from the existing Literature. In North America, we identify 298 nonindigenous species (NIS) of invertebrates and algae that are established in marine and estuarine waters, generating many "apparent patterns" of invasion: (a) The rate of reported invasions has increased exponentially over the past 200 years; (b) Most NIS are crustaceans and molluscs while NIS in taxonomic groups dominated by small organisms are rare; (c) Most invasions have resulted from shipping; (d) More NIS are present along the Pacific coast than the Atlantic and Gulf coasts; (e) Native and source regions of NIS differ among coasts, corresponding to trade patterns. The validity of these apparent patterns remains to be tested, because strong bias exists in the data. Overall, the emergent patterns reflect interactive effects of propagule supply, invasion resistance, and sampling bias. Understanding the relative contribution of each component remains a major challenge for invasion ecology and requires standardized, quantitative measures in space and time that we now lack. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Williams Coll, Maritime Studies Program, Mystic, CT 06355 USA. Univ Washington, Dept Zool, Seattle, WA 98915 USA. RP Ruiz, GM (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. OI Ruiz, Gregory/0000-0003-2499-441X NR 154 TC 557 Z9 593 U1 15 U2 131 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0066-4162 J9 ANNU REV ECOL SYST JI Annu. Rev. Ecol. Syst. PY 2000 VL 31 BP 481 EP 531 DI 10.1146/annurev.ecolsys.31.1.481 PG 51 WC Ecology; Evolutionary Biology SC Environmental Sciences & Ecology; Evolutionary Biology GA 385NX UT WOS:000166011500020 ER PT J AU Dudley, R AF Dudley, R TI The evolutionary physiology of animal flight: Paleobiological and present perspectives SO ANNUAL REVIEW OF PHYSIOLOGY LA English DT Review DE evolution; gigantism; hyperoxia; insect; oxygen ID TRIASSIC MASS EXTINCTION; ATMOSPHERIC OXYGEN; PHANEROZOIC TIME; INSECT FLIGHT; GIANT INTERNEURONS; FOSSIL CHARCOAL; TERRESTRIAL ARTHROPODS; LOCOMOTOR PERFORMANCE; FLYING COCKROACHES; VERTEBRATE FLIGHT AB Recent geophysical analyses suggest the presence of a late Paleozoic oxygen pulse beginning in the late Devonian and continuing through to the late Carboniferous. During this period, plant terrestrialization and global carbon deposition resulted in a dramatic increase in atmospheric oxygen levels, ultimately yielding concentrations potentially as high as 35% relative to the contemporary value of 21%. Such hyperoxia of the late Paleozoic atmosphere may have physiologically facilitated the initial evolution of insect flight metabolism. Widespread gigantism in late Paleozoic insects and other arthropods is also consistent with enhanced oxygen flux within diffusion-limited tracheal systems. Because total atmospheric pressure increases with increased oxygen partial pressure, concurrently hyperdense conditions would have augmented aerodynamic force production in early forms of flying insects. By the late Permian, evolution of decompositional microbial and fungal communities, together with disequilibrium in rates of carbon deposition, gradually reduced oxygen concentrations to values possibly as low as 15%. The disappearance of giant insects by the end of the Permian is consistent with extinction of these taxa for reasons of asphyxiation on a geological time scale. As with winged insects, the multiple historical origins of vertebrate flight in the late Jurassic and Cretaceous correlate temporally with periods of elevated atmospheric oxygen. Much discussion of flight performance in Archaeopteryx assumes a contemporary atmospheric composition. Elevated oxygen levels in the mid- to late Mesozoic would, however, have facilitated aerodynamic force production and enhanced muscle power output for ancestral birds, as well as for precursors to bats and pterosaurs. C1 Univ Texas, Sect Integrat Biol, Austin, TX 78712 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Univ Texas, Sect Integrat Biol, Austin, TX 78712 USA. EM r_dudley@utxvms.cc.utexas.edu NR 210 TC 44 Z9 45 U1 7 U2 46 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0066-4278 EI 1545-1585 J9 ANNU REV PHYSIOL JI Annu. Rev. Physiol. PY 2000 VL 62 BP 135 EP 155 DI 10.1146/annurev.physiol.62.1.135 PG 21 WC Physiology SC Physiology GA 341KF UT WOS:000088589000007 PM 10845087 ER PT J AU Greenhill, JA AF Greenhill, JA TI Man made: Thomas Eakins an the construction of Gilded Age manhood SO ARCHIVES OF AMERICAN ART JOURNAL LA English DT Book Review C1 Smithsonian Inst, Phillips Collect, Washington, DC 20560 USA. RP Greenhill, JA (reprint author), Smithsonian Inst, Phillips Collect, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ARCHIVES AMER ART PI WASHINGTON PA 8TH & F STREETS, WASHINGTON, DC 20560 USA SN 0003-9853 J9 ARCH AM ART J JI Arch. Am. Art J. PY 2000 VL 40 IS 1-2 BP 18 EP 22 PG 5 WC Art SC Art GA 499LG UT WOS:000172572200003 ER PT J AU Ward, DC AF Ward, DC TI Six bridges: The legacy of Othmar H. Ammann SO ARCHIVES OF AMERICAN ART JOURNAL LA English DT Book Review C1 Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. RP Ward, DC (reprint author), Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ARCHIVES AMER ART PI WASHINGTON PA 8TH & F STREETS, WASHINGTON, DC 20560 USA SN 0003-9853 J9 ARCH AM ART J JI Arch. Am. Art J. PY 2000 VL 40 IS 3-4 BP 39 EP 42 PG 4 WC Art SC Art GA 508GG UT WOS:000173079900013 ER PT J AU Ward, DC AF Ward, DC TI Painting the town: Cityscapes of New York SO ARCHIVES OF AMERICAN ART JOURNAL LA English DT Book Review C1 Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. RP Ward, DC (reprint author), Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ARCHIVES AMER ART PI WASHINGTON PA 8TH & F STREETS, WASHINGTON, DC 20560 USA SN 0003-9853 J9 ARCH AM ART J JI Arch. Am. Art J. PY 2000 VL 40 IS 3-4 BP 39 EP 42 PG 4 WC Art SC Art GA 508GG UT WOS:000173079900012 ER PT J AU Ward, DC AF Ward, DC TI Cass Gilbert, architect: Modern traditionalist SO ARCHIVES OF AMERICAN ART JOURNAL LA English DT Book Review C1 Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. RP Ward, DC (reprint author), Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ARCHIVES AMER ART PI WASHINGTON PA 8TH & F STREETS, WASHINGTON, DC 20560 USA SN 0003-9853 J9 ARCH AM ART J JI Arch. Am. Art J. PY 2000 VL 40 IS 3-4 BP 39 EP 42 PG 4 WC Art SC Art GA 508GG UT WOS:000173079900010 ER PT J AU Ward, DC AF Ward, DC TI Grand Central: Gateway to a million lives SO ARCHIVES OF AMERICAN ART JOURNAL LA English DT Book Review C1 Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. RP Ward, DC (reprint author), Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ARCHIVES AMER ART PI WASHINGTON PA 8TH & F STREETS, WASHINGTON, DC 20560 USA SN 0003-9853 J9 ARCH AM ART J JI Arch. Am. Art J. PY 2000 VL 40 IS 3-4 BP 39 EP 42 PG 4 WC Art SC Art GA 508GG UT WOS:000173079900009 ER PT J AU Ward, DC AF Ward, DC TI The creative destruction of Manhattan, 1900-1940 SO ARCHIVES OF AMERICAN ART JOURNAL LA English DT Book Review C1 Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. RP Ward, DC (reprint author), Smithsonian Inst, Natl Portrait Gallery, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ARCHIVES AMER ART PI WASHINGTON PA 8TH & F STREETS, WASHINGTON, DC 20560 USA SN 0003-9853 J9 ARCH AM ART J JI Arch. Am. Art J. PY 2000 VL 40 IS 3-4 BP 39 EP 42 PG 4 WC Art SC Art GA 508GG UT WOS:000173079900011 ER PT J AU Rand, H AF Rand, H TI Jacob Kainen: Memorial recollections SO ARCHIVES OF AMERICAN ART JOURNAL LA English DT Biographical-Item C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Rand, H (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ARCHIVES AMER ART PI WASHINGTON PA 8TH & F STREETS, WASHINGTON, DC 20560 USA SN 0003-9853 J9 ARCH AM ART J JI Arch. Am. Art J. PY 2000 VL 40 IS 1-2 BP 47 EP 48 PG 2 WC Art SC Art GA 499LG UT WOS:000172572200011 ER PT S AU Dalgarno, A AF Dalgarno, A BE Minh, YC VanDishoeck, EF TI Astrochemistry: Historical perspective and future challenges SO ASTROCHEMISTRY: FROM MOLECULAR CLOUDS TO PLANETARY SYSTEMS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 197th Symposium of the International-Astronomical-Union CY AUG 23-27, 1999 CL SOGWIPO, SOUTH KOREA SP Int Astron Union ID POLYCYCLIC AROMATIC-HYDROCARBONS; DIFFUSE INTERSTELLAR-MEDIUM; NEUTRAL-NEUTRAL REACTIONS; EXTRASOLAR GIANT PLANETS; PHOTON-DOMINATED REGIONS; MOLECULAR CLOUD CORES; DISSOCIATIVE RECOMBINATION; BRANCHING FRACTIONS; EARLY UNIVERSE; RED RECTANGLE AB A review is presented of some of the developments in astro-chemistry that have occurred in the past three years, ranging from the chemistry of the early Universe to the chemistry of planetary systems. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM adalgarno@cfa.harvard.edu NR 130 TC 0 Z9 0 U1 0 U2 5 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-034-X J9 IAU SYMP PY 2000 IS 197 BP 1 EP 12 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU35R UT WOS:000175748400001 ER PT S AU Bergin, EA AF Bergin, EA BE Minh, YC VanDishoeck, EF TI Chemical models of collapsing envelopes SO ASTROCHEMISTRY: FROM MOLECULAR CLOUDS TO PLANETARY SYSTEMS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 197th Symposium of the International-Astronomical-Union CY AUG 23-27, 1999 CL SOGWIPO, SOUTH KOREA SP Int Astron Union ID STAR-FORMING REGIONS; CLOUD CORES; EVOLUTION; PROTOSTARS; INFALL AB We discuss recent models of chemical evolution in the developing and collapsing protostellar envelopes associated with low-mass star formation. In particular, the effects of depletion of gas-phase molecules onto grain surfaces is considered. We show that during the middle to late evolutionary stages, prior to the formation of a protostar, various species selectively deplete from the gas phase. The principal pattern of selective depletions is the depletion of sulfur-bearing molecules relative to nitrogen-bearing species: NH(3) and N(2)H(+). This pattern is shown to be insensitive to the details of the dynamics and marginally sensitive to whether the grain mantle is dominated by polar or non-polar molecules. Based on these results we suggest that molecular ions are good tracers of collapsing envelopes. The effects of coupling chemistry and dynamics on the resulting physical evolution are also examined. Particular attention is paid to comparisons between models and observations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Bergin, EA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM ebergin@cfa.harvard.edu NR 23 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-034-X J9 IAU SYMP PY 2000 IS 197 BP 51 EP 60 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU35R UT WOS:000175748400005 ER PT S AU Melnick, GJ AF Melnick, GJ BE Minh, YC VanDishoeck, EF TI First results from the submillimeter wave astronomy satellite - H2O and O-2 discoveries SO ASTROCHEMISTRY: FROM MOLECULAR CLOUDS TO PLANETARY SYSTEMS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 197th Symposium of the International-Astronomical-Union CY AUG 23-27, 1999 CL SOGWIPO, SOUTH KOREA SP Int Astron Union ID MOLECULAR CLOUDS; CHEMISTRY; EMISSION; ABSORPTION; NGC-2071; LINE; FLOW AB The Submillimeter Wave Astronomy Satellite (SWAS) was successfully launched on 5 December 1998 with the goals of studying: (1) the distribution of oxygen in the interstellar medium; (2) the role of H2O and O-2 as gas coolants; and (3) the UV-illuminated surfaces of molecular clouds. To achieve these goals, SWAS is conducting pointed observations of dense (n(H-2) > 10(3) cm(-3)) molecular clouds throughout our Galaxy in either the ground-state or a low-lying transition of five astrophysically important species: H2O, (H2O)-O-18, O-2, CI, and (CO)-C-13. SWAS has made great strides in each of these areas of investigation. This paper will summarize our H2O and O-2 findings one year into the mission. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Melnick, GJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 26 TC 0 Z9 0 U1 1 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-034-X J9 IAU SYMP PY 2000 IS 197 BP 161 EP 174 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU35R UT WOS:000175748400014 ER PT S AU Dalgarno, A AF Dalgarno, A BE Minh, YC VanDishoeck, EF TI Gerhard Herzberg 1905-1999 SO ASTROCHEMISTRY: FROM MOLECULAR CLOUDS TO PLANETARY SYSTEMS SE IAU SYMPOSIA LA English DT Biographical-Item CT 197th Symposium of the International-Astronomical-Union CY AUG 23-27, 1999 CL SOGWIPO, SOUTH KOREA SP Int Astron Union C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Dalgarno, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 3 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-034-X J9 IAU SYMP PY 2000 IS 197 BP 235 EP 236 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU35R UT WOS:000175748400020 ER PT S AU McCarthy, MC AF McCarthy, MC BE Minh, YC VanDishoeck, EF TI Laboratory and astronomical detection of new carbon chains and rings SO ASTROCHEMISTRY: FROM MOLECULAR CLOUDS TO PLANETARY SYSTEMS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 197th Symposium of the International-Astronomical-Union CY AUG 23-27, 1999 CL SOGWIPO, SOUTH KOREA SP Int Astron Union ID RHOMBOIDAL SIC3; TMC-1; SPECTRUM AB Discoveries of large new organic molecules in space help provide a foundation for understanding the role of the chemical bond and organic chemistry on a cosmic scale, and by extension, an opportunity to begin to address the interesting but far more complicated questions of chemical and biological origins and the issues that relate to them. Most of the organic molecules so far detected in the interstellar gas and circumstellar shells by radio telescopes are highly unsaturated carbon chains, a configuration of linear carbon which is unstable at high density, and therefore unfamiliar on Earth. For this reason laboratory detection until quite recently has lagged behind astronomical discovery of many new carbon molecules. The application of Fourier transform microwave spectroscopy to supersonic molecular beams has now largely overcome this obstacle, yielding in just over three years the laboratory detection of forty-four new carbon chains and eight new carbon ring-chains and rings, including two rhomboidal isomers of SiC3. The set consists of 14 polyynes, 20 carbon chain radicals, and 18 free carbenes. For four other triplet chains HC7H, HC9H, HC11H, and HC13H, which by symmetry are nonpolar, strong electronic spectra have been measured in the gas-phase by cavity ringdown absorption spectroscopy. Almost all of these molecules are good candidates for detection in space, and six in fact have now been detected in at least one astronomical source with large radio telescopes during the past two years. The laboratory astrophysics of the entire set is complete for the time being, in the sense that nearly all the rotational transitions of interest to radio astronomy can be calculated to a small fraction of 1 km sec(-1) in equivalent radial velocity. With powerful new radio facilities planned or under construction it would be surprising if many more could not eventually be found. For each of the four new symmetric chains detected in the visible, the wavelength of the origin band has been measured to high accuracy, permitting deliberate searches for these molecules in diffuse and translucent molecular clouds. C1 Harvard Smithsonian Ctr Astrophys, Atom & Mol Phys Div, Cambridge, MA 02138 USA. RP McCarthy, MC (reprint author), Harvard Smithsonian Ctr Astrophys, Atom & Mol Phys Div, 60 Garden St, Cambridge, MA 02138 USA. NR 14 TC 0 Z9 0 U1 0 U2 2 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-034-X J9 IAU SYMP PY 2000 IS 197 BP 273 EP 282 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU35R UT WOS:000175748400024 ER PT S AU Irvine, WM Bergin, EA AF Irvine, WM Bergin, EA BE Minh, YC VanDishoeck, EF TI Molecules in comets: An ISM-solar system connection? SO ASTROCHEMISTRY: FROM MOLECULAR CLOUDS TO PLANETARY SYSTEMS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 197th Symposium of the International-Astronomical-Union CY AUG 23-27, 1999 CL SOGWIPO, SOUTH KOREA SP Int Astron Union ID O1 HALE-BOPP; DENSE INTERSTELLAR CLOUDS; 1996 B2 HYAKUTAKE; C/1995 O1; PROTOPLANETARY DISKS; ACCRETION DISKS; CARBON-MONOXIDE; YOUNG OBJECTS; DEUTERIUM FRACTIONATION; CHEMISTRY AB Our knowledge of the volatile composition of comets has advanced considerably since the last IAU Astrochemistry Symposium, in large part due to the apparition of comet Hale-Bopp and its study with both new ground-based instruments and from spacecraft. Some 23 or 24 coma molecules are now known which are probably, at least in part, volatile constituents of the nucleus. Relative abundances have been measured for rarer isotopomers of molecules containing C-13, N-15, S-34, and D, and significant isotopic fractionation is observed for D-containing species. There are striking similarities in both relative abundances of molecular constituents and in isotopic fractionation between material in dense interstellar clouds and that in cometary comae. Whether this indicates that cometary nuclei consist of relatively unprocessed interstellar matter is less clear, since the observed coma composition is not simply related to the nuclear composition, and since recent chemical models of the outer solar nebula mimic interstellar chemistry in important respects. C1 Univ Massachusetts, Dept Astron, Grad Res Ctr, Amherst, MA 01003 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Univ Massachusetts, Dept Astron, Grad Res Ctr, Amherst, MA 01003 USA. EM irvine@fcrao1.phast.umass.edu; ebergin@cfa.harvard.edu NR 90 TC 4 Z9 4 U1 0 U2 2 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-034-X J9 IAU SYMP PY 2000 IS 197 BP 447 EP 460 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU35R UT WOS:000175748400039 ER PT B AU Joye, W Mandel, E AF Joye, W Mandel, E BE Manset, N Veillet, C Crabtree, D TI SAOTk and TclXPA: Tcl/Tk extensions for astronomy SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS IX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 9th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 99) CY OCT 03-06, 1999 CL HI SP Canada France Hawaii Telescope Corp AB SAOTk is an integrated set of Tcl/Tk canvas widgets for astronomical imaging and data visualization. The widget set is composed of the Frame, Panner, Magnifier, and Colorbar widgets. In addition to "classical" support for imaging FITS data, manipulating colormaps, region marking, coordinate readout (including WCS), etc., SAOTk widgets also support arbitrary image scaling and rotation, advanced PostScript printing, truecolor graphics support, and image mosaics. TclXPA is a Tcl package that implements both the client and server aspects of the XPA messaging system within Tcl. TclXPA allows a Tcl program to exchange data and commands with Tcl programs, Xt programs, or Unix programs. SAOTk and TclXPA are being used in a wide variety of astronomical applications. These applications include general visualization and analysis, real-time instrumentation and calibration, and interactive modeling. These Tcl extensions can be utilized in any standard Tcl/Tk environment to build custom data analysis and visualization applications. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Joye, W (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-047-1 J9 ASTR SOC P PY 2000 VL 216 BP 91 EP 94 PG 4 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BR86E UT WOS:000167857000018 ER PT B AU Rots, A AF Rots, A BE Manset, N Veillet, C Crabtree, D TI The Chandra Data Archive SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS IX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 9th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 99) CY OCT 03-06, 1999 CL HI SP Canada France Hawaii Telescope Corp AB We describe the hierarchy and organization of the data products in the archive of the Chandra X-Ray Observatory. The CDA has adopted the set of FITS conventions developed by the HEASARC, extending them where necessary. This has resulted in a more comprehensive set of conventions on which future missions can build. It is implemented in the Chandra Data Archive environment through a set of standard FITS header modules prescribed for all data products. All CXCDS software is attuned to these standard components but will attempt to perform reasonably for data products from other missions. A brief mention is made of data distribution and time convention issues. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Rots, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 0 TC 5 Z9 5 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-047-1 J9 ASTR SOC P PY 2000 VL 216 BP 184 EP 186 PG 3 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BR86E UT WOS:000167857000039 ER PT B AU Eichhorn, G Accomazzi, A Demleitner, M Grant, CS Kurtz, MJ Murray, SS AF Eichhorn, G Accomazzi, A Demleitner, M Grant, CS Kurtz, MJ Murray, SS BE Manset, N Veillet, C Crabtree, D TI XML in the ADS SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS IX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 9th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 99) CY OCT 03-06, 1999 CL HI SP Canada France Hawaii Telescope Corp AB The ADS software system has been rebuilt in the last few months to introduce several improvements. One major part of the rewrite was to use XML for storing internal data. This provides flexibility that was not available before to merge data from various sources into a unified framework. We describe our current usage of XML and future plans on how to utilize the new capabilities. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Eichhorn, G (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Eichhorn, Guenther/C-9480-2009; KURTZ, Michael /B-3890-2009 OI Eichhorn, Guenther/0000-0002-3032-1978; NR 7 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-047-1 J9 ASTR SOC P PY 2000 VL 216 BP 255 EP 258 PG 4 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BR86E UT WOS:000167857000055 ER PT B AU Tibbetts, M Edgar, R Gaetz, T Jerius, D Michaud, K Nguyen, D AF Tibbetts, M Edgar, R Gaetz, T Jerius, D Michaud, K Nguyen, D BE Manset, N Veillet, C Crabtree, D TI Chandra ground calibration raytrace database and simulator SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS IX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 9th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 99) CY OCT 03-06, 1999 CL HI SP Canada France Hawaii Telescope Corp AB The Chandra Ground Calibration Raytrace Database and Simulator provides simulations of tests performed on the Chandra X-Ray Observatory's High Resolution Mirror Assembly (HRMA). Following ground calibrations at Marshall Space Flight Center, we compiled a database of parameters for each subsystem involved in the calibration effort. Using this database and SAOsac raytrace code, developed from the OSAC suite of programs, we are able to reproduce the environment in which each test was conducted; this enables us to simulate the as-run measurements with the ultimate goal of verifying the fidelity of the HRMA models. Here we describe the structure of the parameter database, ancillary data generated from the database, and comparisons of the simulations to the calibration data. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Tibbetts, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-047-1 J9 ASTR SOC P PY 2000 VL 216 BP 315 EP 318 PG 4 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BR86E UT WOS:000167857000066 ER PT B AU Adams, NR McElroy, DL Evans, IN AF Adams, NR McElroy, DL Evans, IN BE Manset, N Veillet, C Crabtree, D TI Observation interval determination for the Chandra X-ray Observatory SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS IX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 9th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 99) CY OCT 03-06, 1999 CL HI SP Canada France Hawaii Telescope Corp AB Connecting the planned observations and the actual status of the Chandra X-ray Observatory is the observation interval determination pipeline (OBIDET). This collection of tools allows the Chandra X-Ray Center Data System automated processing to process the data through the necessary pipelines based on what was actually observed. The information created by OBIDET is utilized in the creation of the mission time line, and the good time intervals. OBIDET products are also contributors to the verification and validation of the automated processing. We discuss here the data and methods used in the determination of the obi element intervals. The calculation of the overall time of the observation is described. We then go into detail on how the actual configuration is compared with the planned observation and how the tools determine which obi element should guide the data processing. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Adams, NR (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-047-1 J9 ASTR SOC P PY 2000 VL 216 BP 449 EP 452 PG 4 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BR86E UT WOS:000167857000092 ER PT B AU Estes, AN DuPrie, K Harbo, P Pak, K Zografou, P AF Estes, AN DuPrie, K Harbo, P Pak, K Zografou, P BE Manset, N Veillet, C Crabtree, D TI The Chandra Xray Center data archive interfaces SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS IX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 9th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 99) CY OCT 03-06, 1999 CL HI SP Canada France Hawaii Telescope Corp AB The Chandra data archive at the Chandra Xray Center supports automatic pipeline processing via exchange of data and other information. The archive notifies automatic processing about events which change its contents and should trigger processing of an observation. It supports retrieval and ingestion of pipeline input and output data products and provides ancillary data in the form of dynamically generated parameter files. The data archive provides interfaces to access these data products and their associated metadata locally and by the Web. This paper presents the notification mechanism which uses a specially developed server and a number of database triggers. The client interface for data products exchange is also presented, as is the mechanism to generate parameters for a pipeline run and store their updated values as returned by the pipeline for subsequent retrieval at higher levels of processing. In addition, the mechanism for the public access of the data files and metadata via the Web is described. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Estes, AN (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-047-1 J9 ASTR SOC P PY 2000 VL 216 BP 457 EP 460 PG 4 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BR86E UT WOS:000167857000094 ER PT B AU Cresitello-Dittmar, M AF Cresitello-Dittmar, M BE Manset, N Veillet, C Crabtree, D TI Data access layer to support variable inputs using C SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS IX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 9th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 99) CY OCT 03-06, 1999 CL HI SP Canada France Hawaii Telescope Corp AB This paper provides an overview of a software library developed at the Chandra X-Ray Observatory Science Center (CXC) to accommodate variability in the input data products to the aspect determination system. The issue arose that, depending on the decommutation templates used, the inputs to these tools would vary. This variation could be in the number of files, the columns contained in each file, and the form (type) of the column. We needed a layer of software that would dissociate a data column (element) from any particular file. It would also need to handle timing variations for inputs provided at different sample rates. The software described in this paper is a library of functions and structures written in C, that define and manipulate data elements. Tools using this library provide a set of input files containing the required elements. The library functions sort the input files by type, locate the required elements in those files and provide access to them in a time-correlated fashion. The design of the system also makes it easy to define and create new data products. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cresitello-Dittmar, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-047-1 J9 ASTR SOC P PY 2000 VL 216 BP 563 EP 566 PG 4 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BR86E UT WOS:000167857000118 ER PT B AU Noble, MS AF Noble, MS BE Manset, N Veillet, C Crabtree, D TI Elements of the Chandra data analysis system SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS IX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 9th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 99) CY OCT 03-06, 1999 CL HI SP Canada France Hawaii Telescope Corp AB The Chandra X-Ray Observatory was launched on July 23, 1999, with the first public release of the data analysis system (CIAO: Chandra Interactive Analysis of Observations) made availabile on October 4, 1999. This paper presents several of the more novel components of CIAO, including FirstLook, FilterWindow, ChIPS, Prism, and ToolAgent. The functionality is discussed in the context of two issues plaguing modern software - increasing complexity and insufficient reuse - and what approaches were taken with CIAO to mitigate the situation. Chief among these are intuitive GUIs, a thoughtful commingling of both GUI and command line tools, and the development of homogeneous interfaces to libraries and applications already in wide use. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Noble, MS (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-047-1 J9 ASTR SOC P PY 2000 VL 216 BP 603 EP 606 PG 4 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BR86E UT WOS:000167857000126 ER PT B AU He, H Wise, M Ljungberg, M AF He, H Wise, M Ljungberg, M BE Manset, N Veillet, C Crabtree, D TI MKRMF: Multi-dimensional redistribution matrices SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS IX SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 9th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 99) CY OCT 03-06, 1999 CL HI SP Canada France Hawaii Telescope Corp AB A response matrix is a discrete representation of a given instrument's response to incoming photons. In the case of Chandra, each element (HRMA, gratings, focal plane detectors, etc.) has a specific response to an incoming photon's individual physical characteristics, such as energy or position on the sky. These responses can be encoded in the form of a response matrix file or RMF. This presentation is a preliminary report on MKRMF, a new tool developed by the Chandra X-ray Science Center (CXC), to calculate RMFs appropriate for the variety of science instruments on-board Chandra (Wise 1998). This tool provides a number of innovations including the ability to create RMFs on user defined grids and the use of externally encoded instrument redistribution functions for greater flexibility These external redistribution functions are stored using a new FITS format developed by the CXC for encapsulating functions. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP He, H (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-047-1 J9 ASTR SOC P PY 2000 VL 216 BP 636 EP 639 PG 4 WC Astronomy & Astrophysics; Computer Science, Software Engineering; Instruments & Instrumentation SC Astronomy & Astrophysics; Computer Science; Instruments & Instrumentation GA BR86E UT WOS:000167857000135 ER PT J AU Grogin, NA Geller, MJ AF Grogin, NA Geller, MJ TI An imaging and spectroscopic survey of galaxies within prominent nearby voids. II. Morphologies, star formation, and faint companions SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : distances and redshifts; galaxies : fundamental parameters galaxies : photometry; galaxies : statistics; large-scale structure of universe ID SPECTROPHOTOMETRIC STANDARDS; DWARF GALAXIES; BOOTES; ENVIRONMENT; REDSHIFTS; CLUSTERS; UNIVERSE; SEARCH; SLICE AB We analyze the optical properties of similar to 300 galaxies within and around three prominent voids of the Center for Astrophysics Redshift Survey. We determine CCD morphologies and H alpha equivalent widths from our imaging and spectroscopic survey. We also describe a redshift survey of 250 neighboring galaxies in the imaging survey fields. We assess the morphology-density relation, EW(H alpha)-density relation, and the effects of nearby companions for galaxies in low-density environments selected with a smoothed large-scale (5 h(-1) Mpc) galaxy number density n. Both the morphological mix and the H alpha line width distribution of galaxies at modest underdensities, 0.5 < n/(n) over bar less than or equal to 1, are indistinguishable from our control sample at modest overdensities, 1 < n/(n) over bar less than or equal to 2. Both density regions contain a similar fraction of galaxies with early-type (E and SO) morphologies and with absorption-line spectra (approximate to 35%). At the lowest densities, n/(n) over bar less than or equal to 0.5, there is a 3 sigma shift in the distribution of EW(H alpha) away from absorption-line systems (only approximate to 15%) and toward emission-line systems with active star formation-EW(H alpha) similar to 40-100 Angstrom. There is a 2 sigma shift in the morphological distribution away from early types and toward irregular and peculiar morphologies. The redshift survey of projected companions, 80% complete to m(R) = 16.13, demonstrates that the incidence of a close companion in redshift space is insensitive to global density over the range we investigate (0.16 < n/(n) over bar less than or equal to 2). However, the typical velocity separation of close pairs drops significantly (>3 sigma) from Delta cz greater than or similar to 200 km s(-1) at 0.5 < n/(n) over bar less than or equal to 2 down to Delta cz = 103 +/- 20 km s(-1) at n less than or equal to 0.5 (n) over bar. Tn the lowest density environments, galaxies with companions clearly (similar to 4 sigma ) have stronger star formation than comparable galaxies at larger global density (0.5 < n/(n) over bar less than or equal to 2). On the other hand, the distribution of EW(H alpha) for galaxies without nearby companions (closer than approximate to 150 h(-1) kpc and 1000 km s(-1)) varies little over the entire density range. These results, combined with the luminosity- and color-density relations of this sample (Paper I), suggest that the formation and evolution of field galaxies are insensitive to large-scale underdensity down to a threshold of roughly half the mean density. The differences in galaxy properties at the lowest global densities we can explore (n less than or equal to 0.5 (n) over bar) may be explained by (1) a relative scarcity of the small-scale primordial density enhancements needed to form massive early-type/absorption-line galaxies and (2) present-day galaxy encounters that are relatively more effective because of the lower velocity dispersion on small scales (less than or similar to 200 h(-1) kpc) we observe in these regions. In the voids, where the luminous galaxies presumably formed more recently, there should be more gas and dust present for active star formation triggered by nearby companions. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Grogin, NA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 41 TC 58 Z9 58 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD JAN PY 2000 VL 119 IS 1 BP 32 EP 43 DI 10.1086/301179 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 280NW UT WOS:000085109700004 ER PT J AU Koranyi, DM Geller, MJ AF Koranyi, DM Geller, MJ TI Kinematics and mass profile of AWM 7 SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : clusters : individual (AWM 7); galaxies : kinematics and dynamics ID X-RAY; POOR CLUSTERS; RICH CLUSTERS; GALAXIES; EVOLUTION; COMA AB We have measured 492 redshifts (311 new) in the direction of the poor cluster AWM 7 and have identified 179 cluster members (73 new). We use two independent methods to derive a self-consistent mass profile, under the assumptions that the absorption-line galaxies are virialized and that they trace an underlying Navarro, Frenk, & White (NFW) dark matter profile: (1) we fit such an NFW profile to the radial distribution of galaxy positions and to the velocity dispersion profile; (2) we apply the virial mass estimator to the cluster. With these assumptions, the two independent mass estimates agree to similar to 15% within 1.7 h(-1) Mpc, the radial extent of our data; we find an enclosed mass similar to(3 +/- 0.5) x 10(14) h-(1) M.. The largest potential source of systematic error is the inclusion of young emission-line galaxies in the mass estimate. We investigate the behavior of the surface term correction to the virial mass estimator under several assumptions about the velocity anisotropy profile, still within the context of the NFW model, and remark on the sensitivity of derived mass profiles to outliers. We find that one must have data out to a large radius in order to determine the mass robustly, and that the surface term correction is unreliable at small radii. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Koranyi, DM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM dkoranyi@cfa.harvard.edu; mgeller@cfa.harvard.edu NR 41 TC 24 Z9 24 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 EI 1538-3881 J9 ASTRON J JI Astron. J. PD JAN PY 2000 VL 119 IS 1 BP 44 EP 58 DI 10.1086/301166 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 280NW UT WOS:000085109700005 ER PT J AU Quillen, AC Holman, M AF Quillen, AC Holman, M TI Production of star-grazing and star-impacting planetesimals via orbital migration of extrasolar planets SO ASTRONOMICAL JOURNAL LA English DT Article DE celestial mechanics, stellar dynamics; planets and satellites : general; stars : abundances; solar system : formation; solar system : general ID PICTORIS CIRCUMSTELLAR DISK; BETA-PICTORIS; SECULAR RESONANCES; SOLAR-SYSTEM; ASTEROIDS; COMPANION; JUPITER; MOTION; CONSTRAINTS; ACCRETION AB During orbital migration of a giant extrasolar planet via ejection of planetesimals (as studied by Murray et al. in 1998), inner mean-motion resonances can be strong enough to cause planetesimals to graze or impact the star. We integrate numerically the motions of particles which pass through the 3:1 or 4:1 mean-motion resonances of a migrating Jupiter-mass planet. We find that many particles can be trapped in the 3:1 or 4:1 resonances and pumped to high enough eccentricities that they impact the star. This implies that for a planet migrating a substantial fraction of its semimajor axis, a fraction of its mass in planetesimals could impact the star. This process may be capable of enriching the metallicity of the star at a time when the star is no longer fully convective. Upon close approaches to the star, the surfaces of these planetesimals will be sublimated. Orbital migration should cause continuing production of evaporating bodies, suggesting that this process should be detectable with searches for transient absorption lines in young stars. The remainder of the particles will not impact the star but can be ejected subsequently by the planet as it migrates further inward. This allows the planet to migrate a substantial fraction of its initial semimajor axis by ejecting planetesimals. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02158 USA. RP Quillen, AC (reprint author), Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. EM aquillen@as.arizona.edu; mholman@cfa.harvard.edu NR 40 TC 23 Z9 23 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD JAN PY 2000 VL 119 IS 1 BP 397 EP 402 DI 10.1086/301171 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 280NW UT WOS:000085109700037 ER PT J AU Alcala, JM Covino, E Torres, G Sterzik, MF Pfeiffer, MJ Neuhauser, R AF Alcala, JM Covino, E Torres, G Sterzik, MF Pfeiffer, MJ Neuhauser, R TI High-resolution spectroscopy of ROSAT low-mass pre-main sequence stars in Orion SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : low-mass, brown dwarfs; stars : pre-main sequence; stars : rotation; techniques : radial velocities; techniques : spectroscopic; X-rays : stars ID T-TAURI STARS; EMISSION-LINE STARS; SOLAR-TYPE STARS; ALL-SKY SURVEY; X-RAY OBSERVATIONS; RADIAL-VELOCITIES; MOLECULAR CLOUDS; FORMING REGION; OB ASSOCIATION; DARK CLOUD AB High-resolution spectroscopic observations of the lithium-rich stars found on the basis of the ROSAT: All-Sky Survey (RASS) in the general direction of the Orion star forming region are presented. Different properties are derived from the spectra and analyzed: i) the equivalent widths of the lithium 6708 Angstrom absorption line have been measured and a revision of spectral types has been performed: ii) radial velocities (RV) and projected rotational velocities, v sin i, have been derived by application of cross-correlation techniques. A relatively large number of spectroscopic binaries and of suspected spectroscopic binary and multiple systems are found among the stars in the sample. Based on the strength of the lithium line with respect to young open cluster ZAMS stars of the same spectral type, the pre-main sequence nature is confirmed for more than 70% of the stars in the sample. The interrelation of the derived observational properties, such as kinematics, lithium abundance, age and projected rotational velocity of the stars in the sample are analyzed also in connection with the spatial location of the objects. In particular, the comparison between the kinematics of the stars and that of the gas, provided by the CO and CS molecular emission observations, reveals different degrees of clustering of the stars with respect to the cloud material and different kinematical groups can be distinguished. The sample of RASS lithium-rich stars found in the general direction of Orion appears to be a mixture of true Orion stars and, possibly, stars belonging to the Gould Belt. C1 Osservatorio Astron Capodimonte, I-80131 Naples, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. European So Observ, Santiago 19, Chile. Univ Munich, Inst Astron & Astrophys, D-81679 Munich, Germany. Inst Nacl Astrofis Opt & Elect, Puebla 72000, Mexico. Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. RP Alcala, JM (reprint author), Osservatorio Astron Capodimonte, I-80131 Naples, Italy. NR 75 TC 52 Z9 52 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD JAN PY 2000 VL 353 IS 1 BP 186 EP 202 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 275TD UT WOS:000084835500021 ER PT J AU Woitas, J Leinert, C Jahreiss, H Henry, T Franz, OG Wasserman, LH AF Woitas, J Leinert, C Jahreiss, H Henry, T Franz, OG Wasserman, LH TI The nearby M-dwarf system Gliese 866 revisited SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : individual : Gliese 866; stars : binaries : visual; stars : low-mass, brown dwarfs; techniques : interferometric ID BINARY AB We present an improved orbit determination for the visual pair in the M-dwarf triple system Gliese 866 that is based on new speckle-interferometric and HST observations. The system mass is M = 0.34 +/- 0.03 M-.. The masses of the components derived using the mass-luminosity relation are consistent with this mass sum. All three components of Gliese 866 seem to have masses not far from the hydrogen burning mass limit. C1 Max Planck Inst Astron, D-69117 Heidelberg, Germany. Astron Rech Inst, D-69120 Heidelberg, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Lowell Observ, Flagstaff, AZ 86001 USA. RP Woitas, J (reprint author), Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany. EM woitas@mpia-hd.mpg.de NR 14 TC 6 Z9 6 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD JAN PY 2000 VL 353 IS 1 BP 253 EP 256 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 275TD UT WOS:000084835500027 ER PT J AU Spinoglio, L Giannini, T Nisini, B van den Ancker, ME Caux, E Di Giorgio, AM Lorenzetti, D Palla, F Pezzuto, S Saraceno, P Smith, HA White, GJ AF Spinoglio, L Giannini, T Nisini, B van den Ancker, ME Caux, E Di Giorgio, AM Lorenzetti, D Palla, F Pezzuto, S Saraceno, P Smith, HA White, GJ TI Shock excited far-infrared molecular emission around T Tau SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE infrared : ISM : lines and bands; ISM : jets and outflows; ISM : individual objects : T Tau; stars : pre-main sequence; stars : individual : T Tau; stars : formation ID LONG-WAVELENGTH SPECTROMETER; YOUNG STELLAR OBJECTS; PHOTODISSOCIATION REGIONS; MASS-LOSS; STARS; OUTFLOWS; WATER; DISK; GAS; OH AB The first complete far-infrared spectrum of T Tau has been obtained with the LWS spectrometer on-board the Infrared Space Observatory (ISO), which detected strong emission from high-J (J=14-25) CO, para- and ortho-H2O and OH transitions over the wavelength range from 40 to 190 mu m. In addition the [OI]63 mu m, [OI]145 mu m and [CII]158 mu m atomic lines were also detected. Most of the observed molecular emission can be explained by a single emission region at T-300-900 K and nH(2) similar to 10(5-6)cm(-3), With a diameter of about 2-3 arcsec. This corresponds to a very compact region of 300 - 400 AU at the distance of 140 pc. A higher temperature component seems to be needed to explain the highest excitation CO and H2O lines. We derive a water abundance of 1-7 . 10(-5) and an OH abundance of similar to 3.10(-5) with respect to molecular hydrogen, implying H2O and OH enhancements by more than a factor of 10 with respect to the expected ambient gas abundance. The observed cooling in the various species amounts to 0.04 L., comparable to the mechanical luminosity of the outflow, indicating that the stellar winds could be responsible of the line excitation through shocks. In order to explain the observed molecular cooling in T Tau in terms of C-type shock models, we hypothesise that the strong far-ultraviolet radiation field photodissociates water in favour of OH. This would explain the large overabundance of OH observed. The estimated relatively high density and compactness of the observed emission suggest that it originates from the shocks taking place at the base of the molecular outflow emission, in the region where the action of the stellar winds from the two stars of the binary system is important. C1 CNR, Ist Fis Spazio Interplanetario, I-00133 Rome, Italy. Osservatorio Astron Roma, I-00040 Monte Porzio Catone, Italy. Univ Rome La Sapienza, Ist Astron, I-00161 Rome, Italy. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. CESR, F-31028 Toulouse 04, France. Osservatorio Astrofis Arcetri, I-50125 Florence, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA USA. Univ London Queen Mary & Westfield Coll, Dept Phys, London E1 4NS, England. Stockholm Observ, S-13336 Saltsjobaden, Sweden. RP Spinoglio, L (reprint author), CNR, Ist Fis Spazio Interplanetario, Via Fosso Cavaliere 100, I-00133 Rome, Italy. EM luigi@ifsi.rm.cnr.it OI Pezzuto, Stefano/0000-0001-7852-1971; palla, francesco/0000-0002-3321-0456; Giannini, Teresa/0000-0002-0224-096X; Spinoglio, Luigi/0000-0001-8840-1551; , Brunella Nisini/0000-0002-9190-0113 NR 61 TC 21 Z9 21 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD JAN PY 2000 VL 353 IS 3 BP 1055 EP 1064 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285HA UT WOS:000085382600030 ER PT J AU Quataert, E Narayan, R AF Quataert, E Narayan, R TI The cooling flow to accretion flow transition SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; cooling flows; galaxies : individual (M87); hydrodynamics ID ADVECTION-DOMINATED ACCRETION; X-RAY SPECTROSCOPY; MASSIVE BLACK-HOLE; ELLIPTICAL GALAXIES; IONIZED-GAS; M87; CLUSTERS; DISK; HST AB Cooling flows in galaxy clusters and isolated elliptical galaxies are a source of mass for fueling accretion onto a central supermassive black hole. We calculate the dynamics of accreting matter in the combined gravitational potential of a host galaxy and a central black hole assuming a steady state, spherically symmetric how (i.e., no angular momentum). The global dynamics depends primarily on the accretion rate. For large accretion rates no simple, smooth transition between a cooling flow and an accretion flow is possible; the gas cools toward zero temperature just inside its sonic radius, which lies well outside the region where the gravitational influence of the central black hole is important. For accretion rates below a critical value, however, the accreting gas evolves smoothly from a radiatively driven cooling flow at large radii to a nearly adiabatic (Bondi) flow at small radii. We argue that this is the relevant parameter regime for most observed cooling flows. The transition from the cooling flow to the accretion flow should be observable in M87 with the Chandra X-Ray Observatory. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Quataert, E (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 24 TC 32 Z9 32 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 1 PY 2000 VL 528 IS 1 BP 236 EP 242 DI 10.1086/308171 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 277PC UT WOS:000084941100020 ER PT J AU Wex, N Kalogera, V Kramer, M AF Wex, N Kalogera, V Kramer, M TI Constraints on supernova kicks from the double neutron star system PSR B1913+16 SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : individual (B1913+16); stars : kinematics; stars : neutron; supernovae : general ID BINARY PULSAR PSR-1913+16; X-RAY BINARIES; GRAVITATIONAL-RADIATION; RELATIVISTIC GRAVITY; GENERAL-RELATIVITY; MASS-LOSS; EVOLUTION; EXPLOSION; DISTANCES; SUN AB We use recent information on geodetic precession of the binary pulsar B1913+16 along with measurements of its orbital parameters and proper motion to derive new constraints on the immediate progenitor of this double neutron star system. As part of our analysis, we model the motion of the binary in the Galaxy after the second supernova explosion, and we derive constraints on the unknown radial velocity. We also obtain limits on the magnitude and direction of the kick velocity imparted to the pulsar companion during the second supernova explosion. We consider the complete set of possible cases, depending on the kinematic age of the system and the 180 degrees ambiguity in the pulsar spin orientation. Most interestingly, we find that the natal kick must have been directed almost perpendicular to the spin axis of the neutron star progenitor, independent of the specific presupernova configuration. Such a tight constraint on the kick direction has important implications for the physical mechanism responsible for the kick. C1 Max Planck Inst Radioastron, D-53121 Bonn, Germany. Princeton Univ, Joseph Henry Labs, Princeton, NJ 08544 USA. Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Wex, N (reprint author), Max Planck Inst Radioastron, Hugel 69, D-53121 Bonn, Germany. NR 47 TC 66 Z9 67 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 1 PY 2000 VL 528 IS 1 BP 401 EP 409 DI 10.1086/308148 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 277PC UT WOS:000084941100034 ER PT J AU Cusumano, G Maccarone, MC Nicastro, L Sacco, B Kaaret, P AF Cusumano, G Maccarone, MC Nicastro, L Sacco, B Kaaret, P TI Detection of 33.8 millisecond X-ray pulsations in SAX J0635+0533 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : observations; pulsars : general; stars : individual (2EG J0635+0521; SAX J0635+0533); stars : neutron; X-rays : stars ID PULSAR AB We revisited the BeppoSAX observation of SAX J0635+0533, which was suggested as a possible counterpart to the gamma-ray source 2EG J0635+0521. We have discovered a 33.8 ms pulsation from the source and derived an improved position, consistent with the location of the Be star proposed as a binary companion. We interpret the periodicity as the spin period of a neutron star in a binary system with a Be companion. C1 CNR, Ist Fis Cosm Con Applicaz Informat, I-90146 Palermo, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cusumano, G (reprint author), CNR, Ist Fis Cosm Con Applicaz Informat, Via U La Malfa 153, I-90146 Palermo, Italy. RI Nicastro, Luciano/F-5866-2015 OI Nicastro, Luciano/0000-0001-8534-6788 NR 15 TC 23 Z9 23 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 1 PY 2000 VL 528 IS 1 BP L25 EP L28 DI 10.1086/312413 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 277PE UT WOS:000084941300007 ER PT J AU Alves, J Lada, C Lada, E AF Alves, J Lada, C Lada, E TI Towards the frequency and evolutionary timescale of protoplanetary disks SO ASTROPHYSICS AND SPACE SCIENCE LA English DT Article; Proceedings Paper CT Conference on Astrophysical Dynamics CY APR 14-16, 1999 CL UNIV EVORA, EVORA, PORTUGAL SP Geophys Ctr Evora HO UNIV EVORA ID YOUNG STELLAR OBJECTS; LOW-MASS AB In this poster we will present preliminary results from our ongoing near-infrared survey of very young clusters, the majority of them still embedded in their parental molecular cloud. We will draw general conclusions on issues of the frequency and timescales for the initial stages of planet formation. C1 European So Observ, D-8046 Garching, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florida, Gainesville, FL USA. RP Alves, J (reprint author), European So Observ, Karl Schwarzschild Str 2, D-8046 Garching, Germany. NR 8 TC 4 Z9 4 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0004-640X J9 ASTROPHYS SPACE SCI JI Astrophys. Space Sci. PY 2000 VL 272 IS 1-3 BP 213 EP 216 DI 10.1023/A:1002640311834 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 351DH UT WOS:000089142200028 ER PT B AU Karovska, M Wood, K Hack, W AF Karovska, M Wood, K Hack, W BE Kastner, JH Soker, N Rappaport, SA TI Asymmetric outflows in Miras SO ASYMMETRICAL PLANETARY NEBULAE II: FROM ORIGINS TO MICROSTRUCTURES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 2nd Meeting of the Asymmetrical Planetary Nebulae CY AUG 03-06, 1999 CL MIT, CAMBRIDGE, MA HO MIT AB Mira-type variable stars (Miras) are an important link in the evolutionary chain connecting a solar type star to its final stages of evolution as a planetary nebula. We report here direct observation of structures in the vicinity of Mira, the prototype of the Mira-type variables, that could indicate early formation of an asymmetric outflow from an AGE star. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02134 USA. RP Karovska, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02134 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-026-9 J9 ASTR SOC P PY 2000 VL 199 BP 67 EP 70 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ39J UT WOS:000088231900009 ER PT B AU Marengo, M Fazio, GG Hora, JL Hoffmann, WF Dayal, A Deutsch, LK AF Marengo, M Fazio, GG Hora, JL Hoffmann, WF Dayal, A Deutsch, LK BE Kastner, JH Soker, N Rappaport, SA TI Mid-IR imaging of AGB circumstellar envelopes SO ASYMMETRICAL PLANETARY NEBULAE II: FROM ORIGINS TO MICROSTRUCTURES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 2nd Meeting of the Asymmetrical Planetary Nebulae CY AUG 03-06, 1999 CL MIT, CAMBRIDGE, MA HO MIT ID MASS-LOSS; STARS; IRC+10216; SHELLS; COLORS AB AGE stars, the precursors of Planetary Nebulae, exhibit high rates of mass loss and eject material in the form of a slow (10-20 km/s), dusty molecular wind. The general belief that the dust component of AGE circumstellar envelopes have smooth density profiles and spherical symmetry have recently been shaken by new high resolution images, showing that clumpy and asymmetric structures, analogous to the ones observed in Planetary Nebulae, can be present even before the end of the AGE. To illustrate how and when these structures appear, and possibly to address the question of how they may shape the subsequent evolution of these systems, we have started a campaign of mid-IR high spatial resolution imaging of a selected sample of AGE targets. We want here to illustrate our technique, developed for the mid-IR camera MIRAC3, and to show the first results obtained at the NASA Infrared Telescope Facility. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Marengo, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 8 TC 5 Z9 5 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-026-9 J9 ASTR SOC P PY 2000 VL 199 BP 91 EP 94 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ39J UT WOS:000088231900015 ER PT B AU Bourke, T Hyland, AR Robinson, G Luhman, K AF Bourke, T Hyland, AR Robinson, G Luhman, K BE Kastner, JH Soker, N Rappaport, SA TI The evolutionary status of the Frosty Leo Nebula SO ASYMMETRICAL PLANETARY NEBULAE II: FROM ORIGINS TO MICROSTRUCTURES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 2nd Meeting of the Asymmetrical Planetary Nebulae CY AUG 03-06, 1999 CL MIT, CAMBRIDGE, MA HO MIT ID ASYMPTOTIC GIANT BRANCH; STARS; MASS; IRAS-09371+1212; SPECTRA AB We present new observational data for IRAS 09371 +/- 1212, the Frosty Leo Nebula, in the form of infrared spectra from 2.2-2.5 mu m which reveal photospheric bands of CO. The (CO)-C-12/(CO)-C-13 band ratio determined is similar to those exhibited by evolved K giant stars, and supports the proposal that the object is highly evolved. The equivalent width of the CO bands implies, however, that the spectral type lies in the range G5III to K0III, somewhat earlier than K7III, as derived from colours and optical spectra. The smaller equivalent widths of the CO bands may reflect a low metal abundance which could fit well with the considerable height of the source above the galactic plane (>0.9kpc). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Bourke, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 15 TC 1 Z9 1 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-026-9 J9 ASTR SOC P PY 2000 VL 199 BP 171 EP 174 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ39J UT WOS:000088231900030 ER PT B AU Hora, JL Latter, WB Dayal, A Bieging, J Kelly, DM Tielens, AGGM Trammell, SR AF Hora, JL Latter, WB Dayal, A Bieging, J Kelly, DM Tielens, AGGM Trammell, SR BE Kastner, JH Soker, N Rappaport, SA TI HST/NICMOS imaging of the planetary nebula Hubble 12 SO ASYMMETRICAL PLANETARY NEBULAE II: FROM ORIGINS TO MICROSTRUCTURES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 2nd Meeting of the Asymmetrical Planetary Nebulae CY AUG 03-06, 1999 CL MIT, CAMBRIDGE, MA HO MIT ID EMISSION AB Images of Hubble 12 were obtained with the HST/NICMOS instrument in the F110W, F164N, and F166N filters of NIC1, and the F160W, F187N, F190N, F212N, F215N filters of NIC2. The images show the structure of the inner "torus" and lobes much clearer than previous ground-based images. In particular, the [Fe II] lobes are clearly resolved and shown to be distinct from the H-2 emission structures. Apparent changes in the inner ionized and neutral bipolar shell implies periodic mass loss or changes in stellar wind shape or direction. The H-2 in the "eye" is radiatively excited and shows a complex morphology that suggests that several mass ejection events are responsible for producing this structure. The position angle of the H-2 and [Fe II] lobes differ, indicating a possible precession of the ejection axis. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hora, JL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS-65, Cambridge, MA 02138 USA. NR 7 TC 5 Z9 5 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-026-9 J9 ASTR SOC P PY 2000 VL 199 BP 267 EP 270 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ39J UT WOS:000088231900047 ER PT S AU Rothman, LS Zivkovic-Rothman, M AF Rothman, LS Zivkovic-Rothman, M BE Berrington, KA Bell, KL TI Atmospheric molecules SO ATOMIC AND MOLECULAR DATA AND THEIR APPLICATIONS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 2nd International Conference on Atomic and Molecular Data and their Applications (ICAMDATA 2000) CY MAR 26-30, 2000 CL KEBLE COLL, OXFORD, ENGLAND SP Queens Univ, Theoret & Computat Phys Res Div, Sch Math & Phys, Int Union Pure & Appl Phys, NIST, Phys Lab, NIST, Atom Phys Div, NIST, Stand Reference Data Program HO KEBLE COLL ID DATABASE AB The history and development of the HITRAN molecular spectroscopic database is described. HITRAN was created as a compilation of spectroscopic parameters that could serve to provide the basic information to computer programs modeling atmospheric attenuation due to molecular gaseous absorption in the infrared. The first edition of the HITRAN database evolved from monographs on prominent bands of water vapor and carbon dioxide published by the National Bureau of Standards published in the 1960s. This first edition contained a limited set of parameters for bands of the seven most active infrared absorbers in the terrestrial atmosphere. HITRAN has since expanded to cover a broad spectral range from the millimeter through ultraviolet regions, to include absorption cross sections in addition to the discrete line transitions, to include information on about 60 different molecular species, to include mon parameters for sophisticated remote-sensing retrieval programs, and has employed newer distribution methods. C1 Harvard Smithsonian Ctr Astrophys, Atom & Mol Phys Div, Cambridge, MA 02138 USA. RP Rothman, LS (reprint author), Harvard Smithsonian Ctr Astrophys, Atom & Mol Phys Div, MS50,60 Garden St, Cambridge, MA 02138 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-971-8 J9 AIP CONF PROC PY 2000 VL 543 BP 92 EP 103 PG 12 WC Physics, Atomic, Molecular & Chemical SC Physics GA BR46E UT WOS:000166473900008 ER PT S AU Brickhouse, NS AF Brickhouse, NS BE Berrington, KA Bell, KL TI Atomic data in X-ray astrophysics: The Chandra Emission Line Project SO ATOMIC AND MOLECULAR DATA AND THEIR APPLICATIONS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 2nd International Conference on Atomic and Molecular Data and their Applications (ICAMDATA 2000) CY MAR 26-30, 2000 CL KEBLE COLL, OXFORD, ENGLAND SP Queens Univ, Theoret & Computat Phys Res Div, Sch Math & Phys, Int Union Pure & Appl Phys, NIST, Phys Lab, NIST, Atom Phys Div, NIST, Stand Reference Data Program HO KEBLE COLL ID REGIONS AB With the launches of the Chandra X-ray Observatory (CXO) and the S-ray Multimirror Mission (XMM), high resolution X-ray spectroscopy of cosmic sources has begun. Early deep observations of three stellar coronal sources will provide not only invaluable calibration data, but will also give us benchmarks for the atomic data under collisional equilibrium conditions. Analysis of the Chandra X-ray Observatory data, and data from other telescopes taken simultaneously, for these stars is ongoing as part of the Emission Line Project. Goals of the Emission Line Project are (1) to determine and verify accurate and robust diagnostics and (2) to identify and prioritize issues in fundamental spectroscopy which will require further theoretical and/or laboratory work. The Astrophysical Plasma Emission Database will be described in some detail, as it is introducing standardization and flexibility into X-ray spectral modeling. Spectral models of X-ray astrophysical plasmas can be generally classified as dominated by either collisional ionization or by;ri-fay photoionization. While the atomic data needs for spectral models under these two types of ionization are significantly different, there are overlapping data needs, as I will describe. Early results from the Emission Line Project benchmarks are providing an invaluable starting place, but continuing work to improve the accuracy and completeness of atomic data is needed. Addtionally, we consider the possibility that some sources will require that both collisional ionization and photoionization be taken into account, or that time-dependent ionization be considered. Thus plasma spectral models of general use need to be computed over a aide range of physical conditions. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Brickhouse, NS (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 18 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-971-8 J9 AIP CONF PROC PY 2000 VL 543 BP 142 EP 152 PG 11 WC Physics, Atomic, Molecular & Chemical SC Physics GA BR46E UT WOS:000166473900012 ER PT S AU Babb, JF Chung, HK Shurgalin, M Yoshino, K Kirby, K Parkinson, W AF Babb, JF Chung, HK Shurgalin, M Yoshino, K Kirby, K Parkinson, W BE Mancini, RC Phaneuf, RA TI Theoretical and experimental studies of sodium-xenon absorption spectra and applications to lighting SO ATOMIC PROCESSES IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 12th Topical Conference on Atomic Processes in Plasmas CY MAR 19-23, 2000 CL RENO, NV SP Univ Nevada, Phys Dept, Lawrence Livermore Natl Lab, Los Alamos Natl Lab, Dept Energy, Nevada DOE EPSCoR, Univ Nevada ID GAS COLLISION MOLECULES; NA D-LINES; HIGH-PRESSURE; FLUORESCENCE SPECTROSCOPY; INTERATOMIC POTENTIALS; OPTICAL-TRANSITIONS; HIGH-TEMPERATURE; EXCITED-STATES; ATOMS; SATELLITES AB Theory and experiment are being used together to explore spectra from sodium and xenon gas mixtures similar to those used in high pressure lamps. Results from high precision measurements of the absorption coefficients over the wave-length range from 425 to 760 nm are presented with 0.02 nm spectral resolution. Measurements of the sodium density with +/-5 percent uncertainty complement the absorption coefficient measurements. The experimental data are compared to quantum-mechanical spectral calculations that utilize recent cold collision and other data. The spectra are sensitive to the interatomic potentials, especially in the far wings in which molecular features such as vibrational-lotational and satellite structures are exhibited, The particular results far Na-Xe are analyzed in detail. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Babb, JF (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 47 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-976-9 J9 AIP CONF PROC PY 2000 VL 547 BP 190 EP 200 PG 11 WC Optics; Physics, Fluids & Plasmas; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Optics; Physics; Spectroscopy GA BR49V UT WOS:000166658200016 ER PT S AU Brickhouse, NS Drake, JJ AF Brickhouse, NS Drake, JJ BE Mancini, RC Phaneuf, RA TI The Chandra Emission Line Project SO ATOMIC PROCESSES IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 12th Topical Conference on Atomic Processes in Plasmas CY MAR 19-23, 2000 CL RENO, NV SP Univ Nevada, Phys Dept, Lawrence Livermore Natl Lab, Los Alamos Natl Lab, Dept Energy, Nevada DOE EPSCoR, Univ Nevada AB With the launches of the Chandra X-ray Observatory and the X-ray Multi-Mirror Mission-Newton satellite, high resolution X-ray spectroscopy of cosmic sources has begun. Early, deep observations of three stellar coronal sources (Capella, Procyon, and HR 1099) are providing not only invaluable grating calibration data, but also benchmarks for plasma spectral models. These models are needed to interpret data not only from stellar coronae, but also from galaxies, clusters of galaxies, supernova remnants and other astrophysical sources. They have been called into question in recent years as problems with understanding low to moderate resolution X-ray and EUV data have arisen. The Emission Line Project is a collaborative effort sponsored by the Chandra X-ray Center to improve the models, with the first phase concentrating on the comparison of models to the calibration data. Goals of these comparisons are to (1) to determine and verify accurate and robust diagnoistcs and (2) to identify and prioritize issues in fundamental spectroscopy requiring further investigation. We will discuss the progress on this project to date. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Brickhouse, NS (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-976-9 J9 AIP CONF PROC PY 2000 VL 547 BP 265 EP 266 PG 2 WC Optics; Physics, Fluids & Plasmas; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Optics; Physics; Spectroscopy GA BR49V UT WOS:000166658200022 ER PT J AU Robinson, SA Wasley, J Popp, M Lovelock, CE AF Robinson, SA Wasley, J Popp, M Lovelock, CE TI Desiccation tolerance of three moss species from continental Antarctica SO AUSTRALIAN JOURNAL OF PLANT PHYSIOLOGY LA English DT Article DE Bryum pseudotriquetrum; Ceratodon purpureus; chlorophyll fluorescence; Grimmia antarctici; stachyose; soluble carbohydrates ID 2 SPHAGNUM MOSSES; WILKES-LAND; GRIMMIA-ANTARCTICI; COLD-ACCLIMATION; TORTULA-RURALIS; CARBON BALANCE; WATER-DEFICIT; ACCUMULATION; BRYOPHYTES; PLANT AB Tolerance of desiccation was examined in three species of moss, Grimmia antarctici Card., Ceratodon purpureus (Hedw.) Brid. and Bryum pseudotriquetrum (Hedw.) Gaertn., Meyer et Scherb. collected from two sites of contrasting water availability in the Windmill Islands, continental Antarctica. Physiological tolerance to desiccation was measured using chlorophyll fluorescence in plugs of moss during natural drying in the laboratory. Differences in relative water content, rate of drying and the response of photosynthesis to desiccation were observed among the three species and between sites. Of the three species studied, G. antarctici showed the lowest capacity to sustain photosynthetic processes during desiccation, B. pseudotriquetrum had an intermediate response and showed the greatest plasticity and C. purpureus showed the greatest capacity to sustain photosynthesis during desiccation. These results fit well with the known distribution of the three species with G. antarctici being limited to relatively wet sites, C. purpureus being common in the driest sites and B. pseudotriquetrum showing a wide distribution between these two extremes. Levels of soluble carbohydrates were also measured in these samples following desiccation and these indicate the presence of stachyose, an oligosaccharide known to be important in desiccation tolerance in seeds, in B. pseudotriquetrum. Both gross morphology and carbohydrate content are likely to contribute to differences in desiccation tolerance of the moss species. These results indicate that if the Casey region continues to dry out, as a result of local geological uplifting or global climate change, we would expect to see not only reductions in the moss community but also changes in community composition. G. antarctici is likely to become more limited in distribution as C. purpureus and B. pseudotriquetrum expand into drying areas. C1 Univ Wollongong, Dept Biol Sci, Plant Mol Ecophysiol Grp, Wollongong, NSW 2522, Australia. Univ Vienna, Inst Pflanzenphysiol, A-1091 Vienna, Austria. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Robinson, SA (reprint author), Univ Wollongong, Dept Biol Sci, Plant Mol Ecophysiol Grp, Wollongong, NSW 2522, Australia. EM sharonr@uow.edu.au RI Robinson, Sharon/B-2683-2008; Popp, Marianne/E-7559-2012; Lovelock, Catherine/G-7370-2012 OI Robinson, Sharon/0000-0002-7130-9617; Lovelock, Catherine/0000-0002-2219-6855 NR 50 TC 49 Z9 56 U1 1 U2 24 PU CSIRO PUBLISHING PI COLLINGWOOD PA 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA SN 0310-7841 J9 AUST J PLANT PHYSIOL JI Aust. J. Plant Physiol. PY 2000 VL 27 IS 5 BP 379 EP 388 PG 10 WC Plant Sciences SC Plant Sciences GA 318VP UT WOS:000087305600001 ER PT B AU Balog, Z Vinko, J Furesz, G Alfaro, EJ Delgado, AJ Moitinho, A AF Balog, Z Vinko, J Furesz, G Alfaro, EJ Delgado, AJ Moitinho, A BE Smith, MA Henrichs, HF Fabregat, J TI Discovery of new Be stars in the galactic open cluster NGC7128 SO BE PHENOMENON IN EARLY-TYPE STARS, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Meeting of the Be Phenomenon in Early-Type Stars CY JUN 28-JUL 02, 1999 CL ALICANTE, SPAIN AB We present medium resolution spectroscopy (lambda/Delta lambda approximate to 7,000) covering 6500-6750 Angstrom of three emission stars in the highly reddened young open cluster NGC7128. Two of them were previously unknown. The known Be star (V1814 Cyg) is an irregular variable; one of the newly discovered stars is an eclipsing binary (V1481 Cyg) (Jerzykiewicz et al., 1996.). Physical parameters of the cluster have been determined from new UBV and uvbyH beta photometric measurements. C1 Attila Jozsef Univ, Dept Opt, Dom Ter 9, H-6720 Szeged, Hungary. RP Balog, Z (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-045-5 J9 ASTR SOC P PY 2000 VL 175 BP 67 EP 70 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR85Z UT WOS:000167829400010 ER PT J AU Kime, NM Turner, WR Ryan, MJ AF Kime, NM Turner, WR Ryan, MJ TI The transmission of advertisement calls in Central American frogs SO BEHAVIORAL ECOLOGY LA English DT Article DE animal communication; anuran; attenuation; degradation; environmental acoustics; frog ID ACOUSTIC COMMUNICATION; ANIMAL VOCALIZATION; SOUND-TRANSMISSION; HABITAT ACOUSTICS; SONG; PROPAGATION; EVOLUTION; SELECTION; FOREST; SIGNALS AB Acoustic communication signals change over distance due to loss of amplitude and fidelity and it is assumed that signal degradation influences the receiver's ability to detect and decode signals. The degree of degradation depends on the signal's structure and the environment through which it transmits. We broadcast the advertisement calls of 22 species of Central American frogs at two heights within forested and open environments in Panama. We recorded these calls at five distances from the source and estimated signal degradation with a cross-correlation analysis, a measure that combines the effects of decrement in signal amplitude and fidelity. Calls degraded less when broadcast higher above the ground compared to on the ground, and less in open habitat compared to forested habitat; there was an additional interaction between height and environment. Furthermore, calls with low dominant frequencies experienced less degradation than calls with high dominant frequencies. There was no evidence, however that the calls of these frogs have evolved to maximize habitat-specific transmission. C1 Univ Texas, Dept Zool, Austin, TX 78712 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Kime, NM (reprint author), Univ Texas, Dept Zool, Austin, TX 78712 USA. NR 43 TC 74 Z9 81 U1 1 U2 26 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 1045-2249 J9 BEHAV ECOL JI Behav. Ecol. PD JAN-FEB PY 2000 VL 11 IS 1 BP 71 EP 83 DI 10.1093/beheco/11.1.71 PG 13 WC Behavioral Sciences; Biology; Ecology; Zoology SC Behavioral Sciences; Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Zoology GA 337KB UT WOS:000088355900009 ER PT J AU Sun, LX Wilczynski, W Rand, AS Ryan, MJ AF Sun, LX Wilczynski, W Rand, AS Ryan, MJ TI Trade-off in short- and long-distance communication in tungara (Physalaemus pustulosus) and cricket (Acris crepitans) frogs SO BEHAVIORAL ECOLOGY LA English DT Article DE Acris crepitans; auditory system; communication; cricket frogs; Physalaemus pustulosus; sensory biases; sexual selection; tungara frogs ID SEXUAL SELECTION; ACOUSTIC COMMUNICATION; NEOTROPICAL FROG; AUDITORY-SYSTEM; SENSORY EXPLOITATION; MATING PREFERENCES; ANURAN AMPHIBIANS; MATE RECOGNITION; SPRING PEEPERS; FEMALE CHOICE AB Female phonotaxis in tungara (Physalaemus pustulosus) and cricket (Arris crepitans) frogs is biased toward male advertisement calls or call components of lower frequency. This behavioral bias might result in part from a mismatch between the spectral characteristics of the advertisement call and the most sensitive frequency of the peripheral end organ implicated in reception of these sounds. In both species, females are tuned to frequencies lower than average for thr calls in their population. This mismatch, however, represents the situation during short-distance communication. Female frogs can also use the call to detect choruses at long distances, and the spectral distribution of call energy can vary with transmission distance. We used computer simulations to test the hypothesis that there is a better match between tuning and call spectral energy at long distances from the calling male than at short distances by comparing the performance (sound energy received) of the natural tuning curve relative to an optimal tuning curve (i.e., one centered at the. call's dominant frequency). The relative performance of the natural tuning curve increased with distance in tungara frogs. For the two subspecies of cricket frogs, however, the relative performance decreased at longer distances. The performance did not equal the optimal tuning curve at the distances tested. The results indicate that the relationship between calls and auditory tuning cannot be optimal for both long and short distance reception. The relationship between female tuning and call dominant frequency may represent a compromise between short and long distance communication, and the bias toward short or long distances may vary among species. C1 Cent Washington Univ, Dept Biol Sci, Ellensburg, WA 98926 USA. Univ Texas, Dept Zool, Austin, TX 78712 USA. Univ Texas, Dept Psychol, Austin, TX 78712 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Sun, LX (reprint author), Cent Washington Univ, Dept Biol Sci, Ellensburg, WA 98926 USA. NR 62 TC 8 Z9 11 U1 0 U2 7 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 1045-2249 J9 BEHAV ECOL JI Behav. Ecol. PD JAN-FEB PY 2000 VL 11 IS 1 BP 102 EP 109 DI 10.1093/beheco/11.1.102 PG 8 WC Behavioral Sciences; Biology; Ecology; Zoology SC Behavioral Sciences; Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Zoology GA 337KB UT WOS:000088355900012 ER PT J AU Summers, K AF Summers, K TI Mating and aggressive behaviour in dendrobatid frogs from Corcovado National Park, Costa Rica: A comparative study SO BEHAVIOUR LA English DT Article ID DART-POISON FROGS; SEXUAL SELECTION; PATERNAL CARE; PARENTAL CARE; AURATUS; ANURA AB 1. Mating and aggressive behaviour was observed in four species of dendrobatid frogs in Corcovado National Park, Costa Rica: Colostethus nubicola, Colostethus talamancae, Phyllobates vittatus and Dendrobates granuliferus. 2. Males of both species of Colostethus were more likely to respond to call playbacks than male P. vittatus or D. granuliferus. Male D. granuliferus were less likely to be found calling than males of the other species. Conspecific male-male aggression was observed in P. vittatus, but not in the other species. 3. Females were more active during courtship in fl vittatus. Female-female aggression was observed on one occasion in P. vitratus. Females were more likely to reject males than the reverse in all species. 4. These observations suggest that sexual conflict occurs in P. vittatus, but not in C. nubicola or C. talamancae. C1 E Carolina Univ, Dept Biol, Greenville, NC 27858 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Summers, K (reprint author), E Carolina Univ, Dept Biol, Greenville, NC 27858 USA. NR 27 TC 18 Z9 19 U1 0 U2 11 PU BRILL ACADEMIC PUBLISHERS PI LEIDEN PA PLANTIJNSTRAAT 2, P O BOX 9000, 2300 PA LEIDEN, NETHERLANDS SN 0005-7959 J9 BEHAVIOUR JI Behaviour PD JAN PY 2000 VL 137 BP 7 EP 24 DI 10.1163/156853900501845 PN 1 PG 18 WC Behavioral Sciences; Zoology SC Behavioral Sciences; Zoology GA 295NW UT WOS:000085975600002 ER PT B AU Latham, DW AF Latham, DW BE Lemarchand, GA Meech, KJ TI Target selection for planet searches SO BIOASTRONOMY'99, A NEW ERA IN BIOASTRONOMY, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Meeting on A New Era in Search for life in the Universe (Bioastronomy 99) CY AUG 02-06, 1999 CL KOHALA, HI SP Int Astronom Union, Commiss 51 ID ECHELLE-SPECTROMETER; SPECTROGRAPH AB The characteristics of targets now being observed in some of the extrasolar planet searches using precise radial velocities are summarized. This includes the G Dwarf Planet Search, a project to use HIRES with its iodine gas absorption cell on Keck I to carry out a Doppler reconnaissance of more than 1000 solar-type stars under NASA time. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Latham, DW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 9 TC 4 Z9 4 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-044-7 J9 ASTR SOC P PY 2000 VL 213 BP 137 EP 141 PG 5 WC Astronomy & Astrophysics; Biology SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics GA BR93X UT WOS:000168121700019 ER PT S AU Thiel, M AF Thiel, M BE Klein, JCV Schram, FR TI Extended parental care behavior in crustaceans - A comparative overview SO BIODIVERSITY CRISIS AND CRUSTACEA SE CRUSTACEAN ISSUES LA English DT Proceedings Paper CT 4th International Crustacean Congress CY JUL 20-24, 1998 CL AMSTERDAM, NETHERLANDS SP Stichting Crustacea, Brazilian Soc Carcinol, Carcinol Soc Japan, Crustacean Soc, Crustacean Soc China, Grp Etudes & Reflect Evolut Crustaces, Leiden Univ, Div Systemat Zool, Working Grp Biol Sea Lice, Univ Amsterdam Zool Museum, Univ Amsterdam, Board Regents, Inst Inland Water Management & Waste Water Management, Royal Dutch Acad Sci, Dutch Minist Foreign Affairs & Dev Cooperat, European Union, City Amsterdam, Mayor & Aldermen ID SPONGE-DWELLING SHRIMPS; RED SWAMP CRAYFISH; METOPAULIAS-DEPRESSUS; MATERNAL AGGRESSION; PROCAMBARUS-CLARKII; POPULATION BIOLOGY; MARINE AMPHIPODS; BORING AMPHIPOD; HOST-USE; DECAPODA AB Parental care behavior is reported from different crustacean taxa and environments but at present no general pattern has been recognized. The major goal of this review is to synthesize the present knowledge about parental care in crustaceans and to identify whether common traits can be identified. Crustaceans as different as synalpheid shrimp, spider crabs, crayfish, isopods, tanaids and amphipods engage in parental care but no specific morphological traits were connected with this reproductive behavior. Both iteroparous and semelparous crustaceans have been found to engage in parental care. Peracarid species that provide extended parental care for their offspring produce similar numbers of eggs as those peracarids that provide no post-marsupial care. Decapod species with extended parental care (synalpheid shrimp, some brachyuran crabs, many crayfish), produce relatively small numbers of eggs and care for individual broods for relatively long time periods. Highly motile species often carry their offspring on their body or in 'mobile homes', while sedentary species usually host their offspring in/on their dwellings (e.g. tubes and burrows). Crustaceans that carry their offspring hosted only one age cohort of juveniles on their body but those that provided for offspring in/on a dwelling could host up to three subsequent age cohorts of juveniles simultaneously. Food sharing with offspring has been observed in both motile and sedentary species. The most advanced form of parental care is found in terrestrial crustaceans where parents forage in the vicinity of an offspring cradle to which they return food items to feed their young. In general, the high diversity of crustaceans with extended parental care suggests that this reproductive behavior has evolved independently in a variety of crustacean taxa under a variety of environmental conditions. Several examples of convergent evolution of the same form of parental care support this assumption. While the potential for parental care may be high in crustaceans, the occurrence of advanced social behavior probably is limited to crustaceans with an offspring cradle as is indicated by the exclusive finding of return-foraging and multiple juvenile age cohorts among the latter species. Crustaceans offer a unique opportunity to study the evolution of extended parental care since species from a variety of both aquatic and terrestrial environments engage in this reproductive strategy. C1 Smithsonian Marine Stn, Ft Pierce, FL USA. RP Thiel, M (reprint author), Univ Catolica Norte, Fac Ciencias Mar, Campus Guayacan, Coquimbo, Chile. NR 70 TC 29 Z9 29 U1 1 U2 11 PU A A BALKEMA PUBLISHERS PI LEIDEN PA SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS SN 0168-6356 BN 90-5410-478-3 J9 CRUSTACEAN ISS PY 2000 VL 12 BP 211 EP 226 PG 16 WC Fisheries SC Fisheries GA BP98H UT WOS:000086805000018 ER PT S AU Reed, KJ Manning, RB AF Reed, KJ Manning, RB BE Klein, JCV Schram, FR TI Background data on the decapod fauna associated with Cymodocea nodosa meadows in Tunisia, with observations on Clibanarius erythropus SO BIODIVERSITY CRISIS AND CRUSTACEA SE CRUSTACEAN ISSUES LA English DT Proceedings Paper CT 4th International Crustacean Congress CY JUL 20-24, 1998 CL AMSTERDAM, NETHERLANDS SP Stichting Crustacea, Brazilian Soc Carcinol, Carcinol Soc Japan, Crustacean Soc, Crustacean Soc China, Grp Etudes & Reflect Evolut Crustaces, Leiden Univ, Div Systemat Zool, Working Grp Biol Sea Lice, Univ Amsterdam Zool Museum, Univ Amsterdam, Board Regents, Inst Inland Water Management & Waste Water Management, Royal Dutch Acad Sci, Dutch Minist Foreign Affairs & Dev Cooperat, European Union, City Amsterdam, Mayor & Aldermen ID POPULATION; ANOMURA; DIOGENIDAE; CRUSTACEA AB Monthly day and night samples were taken with a pushnet on two different, shallow water Cymodocea nodosa meadows in the Gulf of Tunis, Tunisia, Mediterranean Sea, one at Sidi bou Said, the other at Salammbo. The samples were dominated by six caridean shrimps and one diogenid hermit crab. Processa robusta was the most abundant species and was present at Sidi bou Said throughout the year, in night samples only. Palaemon serratus was slightly more abundant than P. elegans, and showed its greatest abundance between May and September in both day and night samples at Salammbo. Palaemon elegans was most abundant at Salammbo from March to July. Hippolyte inermis was only slightly less abundant than P. serratus at Sidi bou Said. Palaemon adspersus was most abundant at Salammbo, where it occurred from April through June. Hippolyte leptocerus was found all year round at Sidi bou Said. Clibanarius erythropus occurred from May to January; adults dominated at day stations, juveniles at night stations. C1 Smithsonian Inst, Dept Invertebrate Zool, Museum Natl Hist Nat, Washington, DC 20560 USA. RP Reed, KJ (reprint author), Smithsonian Inst, Dept Invertebrate Zool, Museum Natl Hist Nat, Washington, DC 20560 USA. NR 26 TC 2 Z9 2 U1 2 U2 3 PU A A BALKEMA PUBLISHERS PI LEIDEN PA SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS SN 0168-6356 BN 90-5410-478-3 J9 CRUSTACEAN ISS PY 2000 VL 12 BP 401 EP 409 PG 9 WC Fisheries SC Fisheries GA BP98H UT WOS:000086805000035 ER PT J AU Hall, JPW Willmott, KR AF Hall, JPW Willmott, KR TI Patterns of feeding behaviour in adult male riodinid butterflies and their relationship to morphology and ecology SO BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY LA English DT Article DE adaptive syndromes; bait trapping; Ecuador; flight speed; Lepidoptera; metabolic rate; food substrate choice; perching behaviour; puddling; wing area : thoracic volume ratio ID HOVERING INSECT FLIGHT; 2 NECTARIVOROUS BUTTERFLIES; NATURAL FREE-FLIGHT; NEOTROPICAL BUTTERFLIES; OXYGEN-CONSUMPTION; POWER REQUIREMENTS; PUDDLING BEHAVIOR; PAPILIO-GLAUCUS; AERODYNAMICS; BUMBLEBEES AB Adult butterflies are known to visit a wide variety of food substrates, but, with the exception of flower visitation, little is known about what substances are being sought or what determines substrate choice. This is especially true for the Riodinidae, a large family (c. 1300 spp.) of almost exclusively Neotropical butterflies. We present adult male feeding records for 124 species in 41 genera of Riodinidae (out of a total of 441 species in 85 genera collected in the study ), based on ten months sampling in Ecuador. Records of Food substrates visited in this study include flowers, damp sand or mud ('puddling') and rotting carrion. Rotting carrion placed in traps was the most frequently recorded food source in terms of numbers of individuals and taxa, attracting 89 species from 32 genera. A correlation is found between food substrate choice and morphology, specifically wing area to thoracic volume ratio (WA:TV ratio). Our data suggest the possible existence of two adaptive syndromes whose species have significantly different mean WA:TV ratios and differing suites of accompanying ecological traits, with lower ratios being significantly correlated with species that were recorded feeding. Among species recorded feeding, carrion feeders and puddlers have significantly lower mean WA:TV ratios than flower nectarers, and carrion feeders have a lower mean WA:TV ratio than species not recorded on this food source, a correlation that is significant across all tribes and within some tribes (Riodinini and Saratoni). We reanalyse previously published data on flight and morphology for species in other butterfly and moth families and show that the ratio of wing area to thoracic mass is significantly negatively correlated with flight speed and oxygen consumption (a direct indicator of metabolic rate). We suggest that adult male riodinids may puddle and feed at rotting carrion to supplement nutrient stores from larval feeding, not only to increase reproductive success, but also to provide the necessary nutrients to maintain high metabolic rater during rapid flight. (C) 2000 The Linnean Society of London. C1 Univ Florida, Dept Entomol & Nematol, Gainesville, FL 32611 USA. RP Hall, JPW (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Entomol, Washington, DC 20560 USA. NR 82 TC 39 Z9 47 U1 4 U2 17 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0024-4066 J9 BIOL J LINN SOC JI Biol. J. Linnean Soc. PD JAN PY 2000 VL 69 IS 1 BP 1 EP 23 DI 10.1006/bijl.1999.0345 PG 23 WC Evolutionary Biology SC Evolutionary Biology GA 277BG UT WOS:000084912400001 ER PT J AU Janik, M Kleinhans, FW Hagedorn, M AF Janik, M Kleinhans, FW Hagedorn, M TI Microinjection of cryoprotectants into the yolk of zebrafish embryos (Brachydanio rerio). SO BIOLOGY OF REPRODUCTION LA English DT Meeting Abstract C1 Smithsonian Inst, Natl Zool Pk & Conservat & Res Ctr, Washington, DC USA. Indiana Univ Purdue Univ, Dept Phys, Indianapolis, IN 46205 USA. NR 0 TC 2 Z9 2 U1 0 U2 2 PU SOC STUDY REPRODUCTION PI MADISON PA 1603 MONROE ST, MADISON, WI 53711-2021 USA SN 0006-3363 J9 BIOL REPROD JI Biol. Reprod. PY 2000 VL 62 SU 1 MA 102 BP 146 EP 146 PG 1 WC Reproductive Biology SC Reproductive Biology GA 328QV UT WOS:000087862300169 ER PT J AU Pelican, KM Brown, JL Wildt, DE Ottinger, MA Howard, JG AF Pelican, KM Brown, JL Wildt, DE Ottinger, MA Howard, JG TI Short term suppression of the estrous cycle of the domestic cat using levonorgestrel versus a GnRH antagonist, as assessed by fecal steroids. SO BIOLOGY OF REPRODUCTION LA English DT Meeting Abstract C1 Smithsonian Inst, Conservat & Res Ctr, Natl Zool Pk, Front Royal, VA USA. Univ Maryland, Dept Anim & Avian Sci, College Pk, MD 20742 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC STUDY REPRODUCTION PI MADISON PA 1603 MONROE ST, MADISON, WI 53711-2021 USA SN 0006-3363 J9 BIOL REPROD JI Biol. Reprod. PY 2000 VL 62 SU 1 MA 115 BP 151 EP 151 PG 1 WC Reproductive Biology SC Reproductive Biology GA 328QV UT WOS:000087862300182 ER PT J AU Spindler, RE Wildt, DE AF Spindler, RE Wildt, DE TI Influence of companion embryo age and quality on in vitro development of felid embryos. SO BIOLOGY OF REPRODUCTION LA English DT Meeting Abstract C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC STUDY REPRODUCTION PI MADISON PA 1603 MONROE ST, MADISON, WI 53711-2021 USA SN 0006-3363 J9 BIOL REPROD JI Biol. Reprod. PY 2000 VL 62 SU 1 MA 538 BP 318 EP 319 PG 2 WC Reproductive Biology SC Reproductive Biology GA 328QV UT WOS:000087862300602 ER PT S AU Olive, JF Barret, D Boirin, L Grindlay, JE AF Olive, JF Barret, D Boirin, L Grindlay, JE BE Makishima, K Piro, L Takahashi, T TI RXTE broad band X-ray spectrum of the burster 1E1724-3045 SO BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 1 Symposium of COSPAR Scientific Commission E held at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP European Space Agcy, Int Astronom Union, Inst Space & Astronaut Sci, Tata Inst Fdn Res, Comm Space Res ID GLOBULAR-CLUSTER TERZAN-2; BINARIES AB The X-ray burster 1E1724-3045 located in the globular cluster Terzan 2 is known as one of the persistent (though variable) hard X-ray sources as shown by the SIGMA observations of the Galactic Center region. 1E1724-3045 was observed with the PCA and HEXTE experiments onboard the Rossi X-ray Timing Explorer (RXTE) on November 1996 for about 100 ksec. The broad band spectral capability and sensitivity of RXTE enables to study simultaneously the X-ray (3-20 keV) and hard X-ray components (E>20 keV) of this source. During the observation, this "Atoll" source was in its "Island" state characterized by a hard Comptonized spectrum with an electron temperature kT(e) similar to 29 keV, an optical depth tau similar to 2.9 (spherical geometry) and a temperature of the "seed" photons of kT(W)similar to 1.2 keV. Below 5 keV, there is a soft excess which we fit with a blackbody of kT(BB)similar to 0.67 keV. The Comptonization temperature is significantly lower those observed for black holes candidates in their low luminosity state (kT(e) greater than or similar to 50 keV). Finally, our observation allows us to associate the presence of an hard tail with a low luminosity X-ray state (1-20 keV luminosity of 1.0x10(37) ergs s(-1) at 7.7 kpc). (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 CNRS, UPS, CESR, F-31028 Toulouse 04, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Olive, JF (reprint author), CNRS, UPS, CESR, 9 Ave Colonel Roche, F-31028 Toulouse 04, France. NR 13 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 2000 VL 25 IS 3-4 BP 369 EP 374 DI 10.1016/S0273-1177(99)00760-7 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP51E UT WOS:000085367000003 ER PT S AU Barret, D Olive, JF Boirin, L Grindlay, JE Swank, JH Smale, AP AF Barret, D Olive, JF Boirin, L Grindlay, JE Swank, JH Smale, AP BE Makishima, K Piro, L Takahashi, T TI No high frequency quasi-periodic oscillations from the X-ray burster 1E1724-3045 SO BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 1 Symposium of COSPAR Scientific Commission E held at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP European Space Agcy, Int Astronom Union, Inst Space & Astronaut Sci, Tata Inst Fdn Res, Comm Space Res ID DISCOVERY AB The type I X-ray burster 1E1724-3045 located in the globular cluster Terzan 2 was observed by the Rossi X-ray Timing Explorer (RXTE) while it was in a Island state, displaying both intense flickering and a hard Comptonized spectrum. No statistically significant High Frequency Quasi-Periodic Oscillations (HFQPOs) were detected. A 3 sigma upper limit on the fractional Root Mean Squared (RMS) of similar to 2.5% has thus been derived in the 5-30 keV band. Attenuation of the QPO signal in a scattering corona of optical depth similar to 3 as inferred from the spectral analysis could provide an explanation for the non-detection of HFQPOs from 1E1724-3045. (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 CNRS, UPS, CESR, F-31028 Toulouse, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Barret, D (reprint author), CNRS, UPS, CESR, 9 Ave Colonel Roche, F-31028 Toulouse, France. RI Swank, Jean/F-2693-2012 NR 11 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 2000 VL 25 IS 3-4 BP 383 EP 386 DI 10.1016/S0273-1177(99)00763-2 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP51E UT WOS:000085367000006 ER PT S AU Boirin, L Barret, D Olive, JF Grindlay, JE Bloser, PF AF Boirin, L Barret, D Olive, JF Grindlay, JE Bloser, PF BE Makishima, K Piro, L Takahashi, T TI Low and high frequency quasi-periodic oscillations in 4U1915-05 SO BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 1 Symposium of COSPAR Scientific Commission E held at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP European Space Agcy, Int Astronom Union, Inst Space & Astronaut Sci, Tata Inst Fdn Res, Comm Space Res ID DISCOVERY AB The burster and dipper Low Mass X-ray Binary (LMXB) 4U1915-05 (also known as XB1916-053) was observed by the Rossi X-ray Timing Explorer (RXTE) 19 times for a total exposure of 140 ks between 1996 February and October. Here we report on the discovery of Low Frequency (10-40 Hz) Quasi-Periodic Oscillations (LFQPOs) from 4U1915-05. The properties of the LFQPOs are related to the presence of the High Frequency QPOs (HFQPOs) detected simultaneously. We have observed a correlation between the LFQPO frequency and source count rate, as well as a correlation (linear) between the LFQPOs and HFQPOs. Both results cannot be explained by a Beat Frequency Model (BFM). They are also hardly compatible with predictions from the inner disk precession model. (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 CESR, F-31028 Toulouse 04, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Boirin, L (reprint author), CESR, 9 Ave Colonel Roche, F-31028 Toulouse 04, France. NR 12 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 2000 VL 25 IS 3-4 BP 387 EP 390 DI 10.1016/S0273-1177(99)00764-4 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP51E UT WOS:000085367000007 ER PT S AU Kataoka, J Mattox, JR Quinn, J Kubo, H Makino, F Takahashi, T Inoue, S Hartmann, RC Madejski, GM Sreekumar, P Wagner, SJ AF Kataoka, J Mattox, JR Quinn, J Kubo, H Makino, F Takahashi, T Inoue, S Hartmann, RC Madejski, GM Sreekumar, P Wagner, SJ BE Makishima, K Piro, L Takahashi, T TI A study of high energy emission from the TeV blazar Mrk 501 during multiwavelength observations in 1996 SO BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 1 Symposium of COSPAR Scientific Commission E held at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP European Space Agcy, Int Astronom Union, Inst Space & Astronaut Sci, Tata Inst Fdn Res, Comm Space Res ID GAMMA-RAY EMISSION; RADIATION; MODEL AB We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA. EGRET, Whipple, and optical telescopes. We report here for the first time the detection of GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in April/May 1996, with 4.0 sigma for E > 100 MeV, and 5.2 sigma for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that this flat spectrum cannot be explained by either 2nd order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. Boston Univ, Dept Astron, Boston, MA 02215 USA. Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. Tokyo Metropolitan Univ, Dept Phys, Hachioji, Tokyo 1920397, Japan. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Landessternwarte Heidelberg, D-69117 Heidelberg, Germany. RP Kataoka, J (reprint author), Inst Space & Astronaut Sci, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 2298510, Japan. NR 14 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 2000 VL 25 IS 3-4 BP 737 EP 740 DI 10.1016/S0273-1177(99)00832-7 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP51E UT WOS:000085367000075 ER PT S AU Comastri, A Fiore, F Giommi, P La Franca, F Elvis, M Matt, G Molendi, S Perola, GC AF Comastri, A Fiore, F Giommi, P La Franca, F Elvis, M Matt, G Molendi, S Perola, GC BE Makishima, K Piro, L Takahashi, T TI The BeppoSAX view of the hard X-ray background SO BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 1 Symposium of COSPAR Scientific Commission E held at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP European Space Agcy, Int Astronom Union, Inst Space & Astronaut Sci, Tata Inst Fdn Res, Comm Space Res ID ACTIVE GALACTIC NUCLEI; DEEP ROSAT FIELDS; LUMINOSITY FUNCTION; ASCA OBSERVATIONS; LOCKMAN FIELD; SKY; GALAXIES; SPECTRA; COUNTS; QSO AB First results on a medium-deep X-ray survey in the "new" 5-10 keV band carried out with the MECS detectors onboard BeppoSAX are presented. The High Energy Llarge Area Survey (HELLAS) is aimed to directly explore a band where the energy density of the X-ray background is more than twice than that in the soft (0.5-2.0 keV) band. The optical identification follow-up of the first ten HELLAS hard X-ray sources indicate that Active Galactic Nuclei are the dominant population at 5-10 keV fluxes of the order of 10(-13) erg cm(-2) s(-1). We discuss the implications of these findings for the AGN synthesis models for the XRB. (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 Osservatorio Astron Bologna, I-40127 Bologna, Italy. Osservatorio Astron Roma, I-00044 Monteporzio Catone, Italy. Nuova Telespazio, SAX Sci Data Ctr, I-00131 Rome, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Roma Tre, Dipartimento Fis, I-00146 Rome, Italy. CNR, Ist Fis Cosm & Tecnol Relat, I-20133 Milan, Italy. RP Comastri, A (reprint author), Osservatorio Astron Bologna, Via Ranzani 1, I-40127 Bologna, Italy. RI La Franca, Fabio/G-9631-2012; Comastri, Andrea/O-9543-2015; OI Comastri, Andrea/0000-0003-3451-9970; giommi, paolo/0000-0002-2265-5003; La Franca, Fabio/0000-0002-1239-2721; Molendi, Silvano/0000-0002-2483-278X; Fiore, Fabrizio/0000-0002-4031-4157 NR 28 TC 3 Z9 3 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 2000 VL 25 IS 3-4 BP 833 EP 838 DI 10.1016/S0273-1177(99)00850-9 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP51E UT WOS:000085367000093 ER PT J AU Chinea, JD Acevedo-Rodriguez, P Axelrod, FS AF Chinea, JD Acevedo-Rodriguez, P Axelrod, FS TI List of Tracheophyta species in Punta Guayanes (Yabucoa, Puerto Rico) SO CARIBBEAN JOURNAL OF SCIENCE LA Spanish DT Article C1 Univ Illinois, Dept Nat Resources & Environm Sci, Urbana, IL 61801 USA. Smithsonian Inst, US Natl Herbarium, Washington, DC 20560 USA. Univ Puerto Rico, Dept Biol, Rio Piedras, PR 00931 USA. RP Chinea, JD (reprint author), Univ Illinois, Dept Nat Resources & Environm Sci, Urbana, IL 61801 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU UNIV PUERTO RICO, PI MAYAGUEZ PA COLLEGE ARTS SCIENCES, MAYAGUEZ, PUERTO RICO 00680 USA SN 0008-6452 J9 CARIBB J SCI JI Caribb. J. Sci. PY 2000 VL 36 IS 1-2 BP 141 EP 145 PG 5 WC Biodiversity Conservation SC Biodiversity & Conservation GA 407BT UT WOS:000167252100013 ER PT J AU Gifford, ME Powell, R Steiner, WE AF Gifford, ME Powell, R Steiner, WE TI Relationship of diet and prey availability in Aristelliger cochranae, a gecko from Navassa Island, West Indies SO CARIBBEAN JOURNAL OF SCIENCE LA English DT Article C1 Avila Coll, Dept Biol, Kansas City, MO 64145 USA. Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Powell, R (reprint author), Avila Coll, Dept Biol, Kansas City, MO 64145 USA. RI Gifford, Matthew/C-9500-2012 NR 14 TC 2 Z9 2 U1 2 U2 4 PU UNIV PUERTO RICO, PI MAYAGUEZ PA COLLEGE ARTS SCIENCES, MAYAGUEZ, PUERTO RICO 00680 USA SN 0008-6452 J9 CARIBB J SCI JI Caribb. J. Sci. PY 2000 VL 36 IS 3-4 BP 323 EP 326 PG 4 WC Biodiversity Conservation SC Biodiversity & Conservation GA 407BV UT WOS:000167252300015 ER PT B AU West, WR AF West, WR GP NATLIONAL MUSEUM OF THE AMERICAN INDIAN NATLIONAL MUSEUM OF THE AMERICAN INDIAN TI Cultural rethink SO CHANGING PRESENTATION OF THE AMERICAN INDIAN: MUSEUMS AND NATIVE CULTURES LA English DT Proceedings Paper CT Symposium on the Changing Presentation of the American Indian CY OCT 08, 1995 CL NATL MUSEUM AMER INDIAN, NEW YORK, NY HO NATL MUSEUM AMER INDIAN C1 Smithsonian Inst, Natl Museum Amer Indian, Washington, DC 20560 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIV WASHINGTON PRESS PI SEATTLE PA SEATTLE, WA 98105 USA BN 0-295-97781-7 PY 2000 BP 99 EP 102 PG 4 WC Art SC Art GA BQ53C UT WOS:000088669300008 ER PT J AU McShea, WJ Reese, EG Small, TW Weldon, PJ AF McShea, WJ Reese, EG Small, TW Weldon, PJ TI An experiment on the ability of free-ranging turkey vultures (Cathartes aura) to locate carrion by chemical cues SO CHEMOECOLOGY LA English DT Article C1 Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP McShea, WJ (reprint author), Smithsonian Inst, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. NR 7 TC 2 Z9 2 U1 0 U2 25 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0937-7409 J9 CHEMOECOLOGY JI Chemoecology PY 2000 VL 10 IS 1 BP 49 EP 50 DI 10.1007/s000490050007 PG 2 WC Biochemistry & Molecular Biology; Ecology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology GA 344KJ UT WOS:000088757500007 ER EF