FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Esry, BD Greene, CH AF Esry, BD Greene, CH TI Spontaneous spatial symmetry breaking in two-component Bose-Einstein condensates SO PHYSICAL REVIEW A LA English DT Article ID HARTREE-FOCK THEORY AB We discuss the general features of spontaneous spatial symmetry breaking in trapped two-component alkali-metal-atom Bose-Einstein condensates, and give qualitative guidelines for when it will occur. We further show that the Hartree-Fock equations admit symmetry-broken solutions for as few as two trapped atoms, discussing the particular system of one (85)Rb atom and one (87)Rb atom. It is also shown that the critical value of the interspecies scattering length for a mixture of Na and Rb in an isotropic trap depends strongly on the number of atoms in a manner not described by the standard Thomas-Fermi phase separation condition. [S1050-2947(99)00101-8]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. RP Esry, BD (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RI Greene, Chris/C-3821-2011; Esry, Brett/H-7511-2013 OI Greene, Chris/0000-0002-2096-6385; Esry, Brett/0000-0003-3207-8526 NR 22 TC 69 Z9 69 U1 0 U2 4 PU AMER 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 1999 VL 59 IS 2 BP 1457 EP 1460 DI 10.1103/PhysRevA.59.1457 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 169YW UT WOS:000078778500071 ER PT J AU Forrey, RC Dalgarno, A Schmiedmayer, J AF Forrey, RC Dalgarno, A Schmiedmayer, J TI Determining the electron forward-scattering amplitude using electron interferometry SO PHYSICAL REVIEW A LA English DT Article ID ABSORPTION FINE-STRUCTURE; SODIUM MATTER WAVES; REFRACTION; MOLECULES; INDEX; GASES AB We describe a method for measuring the forward-scattering amplitude for electron collisions with atoms or molecules. Our scheme uses a gas cell in one arm of an electron interferometer and measures the resulting attenuation and phase shift of the electron matter wave. The complex index of refraction of the gas is determined along with the forward-scattering amplitude. Calculations of the scattering of electrons by atoms are performed using a self-energy potential obtained by treating the atom as an inhomogeneous electron gas. The results indicate that the proposed experiments are feasible. [S1050-2937(99)50902-5]. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Innsbruck, A-6020 Innsbruck, Austria. RP Forrey, RC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Schmiedmayer, Jorg/B-4717-2008 OI Schmiedmayer, Jorg/0000-0001-7799-5614 NR 25 TC 9 Z9 9 U1 0 U2 1 PU AMER 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 1999 VL 59 IS 2 BP R942 EP R945 DI 10.1103/PhysRevA.59.R942 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 169YW UT WOS:000078778500009 ER PT J AU Tseng, CH Mair, RW Wong, GP Williamson, D Cory, DG Walsworth, RL AF Tseng, CH Mair, RW Wong, GP Williamson, D Cory, DG Walsworth, RL TI Magnetic resonance imaging of laser polarized liquid xenon SO PHYSICAL REVIEW E LA English DT Article ID VAPOR CRITICAL-POINT; DIFFUSION-COEFFICIENT; POROUS-MEDIA; FLUIDS; NMR; GAS; DYNAMICS; PROBE AB We demonstrate magnetic resonance imaging (MRI) of laser polarized liquid xenon, and image exchange between the liquid and vapor phases. The exceptionally large magnetization density of this liquid should allow MRI with micron-scale spatial resolution without signal averaging. Applications may include imaging of density equilibration and convective flow near xenon's liquid-vapor critical point, tow-field imaging of porous media microstructure, and mapping of the dynamics of two-phase (liquid-gas) flows. [S1063-651X(99)05602-0]. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Brigham & Womens Hosp, Dept Radiol, Boston, MA 02115 USA. RP Tseng, CH (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 33 TC 14 Z9 14 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD FEB PY 1999 VL 59 IS 2 BP 1785 EP 1788 DI 10.1103/PhysRevE.59.1785 PN A PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 169ZF UT WOS:000078779500066 ER PT J AU Torres, G AF Torres, G TI Substellar companion masses from minimal radial velocity or astrometric information: A Monte Carlo approach SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID STARS; SYSTEMS AB Slow drifts detected in the radial velocities of a number of nearby stars indicate the presence of companions in orbit around the primaries, even though a complete spectroscopic orbital solution is not possible because of the long periods. Some of these companions may have substellar masses and are thus of considerable interest for the study of the characteristics of extrasolar planets and brown dwarfs. Similar indications can be obtained from the measurement of small astrometric accelerations of the primary star, either from the ground or more likely from future highly precise space astrometry missions. We show here that a single measurement of the angular separation of such companions, if they can be imaged directly, provides valuable statistical information on their mass when combined with the accelerations. We derive the probability distribution of the companion mass separately for the radial velocity case and for the astrometric case by Monte Carlo simulations, and illustrate the application of the technique with several examples. The information on the masses of such wide substellar companions is complementary to that from closer spectroscopic companions, and a full analysis of the mass distribution of these objects should include both to avoid possible biases. 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 26 TC 37 Z9 37 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 FEB PY 1999 VL 111 IS 756 BP 169 EP 176 DI 10.1086/316313 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 163PG UT WOS:000078413500002 ER PT J AU Patten, BM Pavlovsky, CM AF Patten, BM Pavlovsky, CM TI A photometric survey for low-mass members of IC 2391 SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID SOLAR-TYPE STARS; CLUSTER IC-2391; PLEIADES; ROSAT AB A VRI photometric survey has been conducted in the young open cluster IC 2391 to identify candidate low-mass cluster members. Photometry for some 10,725 objects, ranging from V = 10 to V = 20, were extracted from 21 CCD fields positioned within 1 degrees of the nominal cluster center [alpha(2000) = 08(h)42(m), delta(2000) = -53 degrees 00']. Seventeen stars have been identified as candidate cluster members with (V-T) colors ranging from 2.78 to 3.72. The masses of these candidate members are estimated to range from 0.25 to 0.09 M.. If these stars are indeed IC 2391 members, they will help to rectify an apparent deficit of low-luminosity stars in the luminosity function of this cluster. C1 Smith Coll, Five Coll, Dept Astron, Northampton, MA 01063 USA. RP Patten, BM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 35 TC 12 Z9 12 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 FEB PY 1999 VL 111 IS 756 BP 210 EP 216 DI 10.1086/316315 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 163PG UT WOS:000078413500007 ER PT J AU Millan-Gabet, R Schloerb, FP Traub, WA Carleton, NP AF Millan-Gabet, R Schloerb, FP Traub, WA Carleton, NP TI A NICMOS3 camera for fringe detection at the IOTA interferometer SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID ASTRONOMY AB We describe a new instrument, based on a NICMOS3 array, for the detection of interference fringes in the near-infrared at the Infrared-Optical Telescope Array. The camera saw "first fringes" in Spring of 1997 and has since been in routine use for a variety of astrophysical investigations. We present its design characteristics and parameters, which result in magnitude limits for fringe detection of J = 8.4, H = 8.5, and K' = 6.5. C1 Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Millan-Gabet, R (reprint author), Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA. NR 8 TC 22 Z9 22 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 FEB PY 1999 VL 111 IS 756 BP 238 EP 245 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 163PG UT WOS:000078413500011 ER PT J AU Forman, P AF Forman, P TI Science and the humanities in the postmodern age SO REVISTA DE OCCIDENTE LA Spanish DT Article C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Forman, P (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU FUNDACION JOSE ORTEGA Y GASSET PI MADRID PA REVISTA DE OCCIDENTE FORTUNY 53, 28010 MADRID, SPAIN SN 0034-8635 J9 REV OCCIDENTE JI Rev. Occidente PD FEB PY 1999 IS 213 BP 110 EP 121 PG 12 WC Humanities, Multidisciplinary SC Arts & Humanities - Other Topics GA 170QL UT WOS:000078817500009 ER PT J AU Jenny, M Bayer, C Dorr, LJ AF Jenny, M Bayer, C Dorr, LJ TI Aethiocarpa reduced to Harmsia (Malvaceae, Dombeyoideae) SO TAXON LA English DT Article AB The unispecific genus Aethiocarpa was distinguished from Harmsia principally on the basis of ovary and fruit structure: one-seeded, unilocular ovaries and indehiscent fruit versus two-seeded, bilocular ovaries and tardily dehiscent fruit, respectively. A critical re-examination of ovary characters, however, reveals that both genera share biovulate unilocular ovaries, which are unique within subfamily Dombeyoideae (Malvaceae). Differences in indumentum, inflorescence morphology, and number of seed per fruit, which were cited as ancillary characters distinguishing Aethiocarpa from Harmsia, do not appear to justify the recognition of two different genera. Aerhiocarpa is therefore considered to be a synonym of Harmsia and the new combination H. lepidota is proposed. C1 Palmengarten Stadt Frankfurt, D-60323 Frankfurt, Germany. Univ Hamburg, Inst Allgemeine Bot, D-22609 Hamburg, Germany. Smithsonian Inst, Natl Museum Nat Hist, Dept Bot MRC166, Washington, DC 20560 USA. RP Jenny, M (reprint author), Palmengarten Stadt Frankfurt, Siesmayerstr 61, D-60323 Frankfurt, Germany. NR 7 TC 3 Z9 5 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 1999 VL 48 IS 1 BP 3 EP 6 DI 10.2307/1224611 PG 4 WC Plant Sciences; Evolutionary Biology SC Plant Sciences; Evolutionary Biology GA 172FL UT WOS:000078912800001 ER PT J AU Herre, EA Knowlton, N Mueller, UG Rehner, SA AF Herre, EA Knowlton, N Mueller, UG Rehner, SA TI The evolution of mutualisms: exploring the paths between conflict and cooperation SO TRENDS IN ECOLOGY & EVOLUTION LA English DT Review ID ENDOSYMBIOTIC BACTERIA; ACCELERATED EVOLUTION; YUCCA MOTHS; FUNGI; DIVERSITY; SYMBIOSES; PHYLOGENY; CONSEQUENCES; MAINTENANCE; SELECTION AB Mutualisms are of fundamental importance in all ecosystems but their very existence poses a series of challenging evolutionary questions. Recently, the application of molecular analyses combined with theoretical advances have transformed our understanding of many specific systems, thereby contributing to the possibility of a more general understanding of the factors that influence mutualisms. C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. Univ Maryland, Dept Zool, College Pk, MD 20742 USA. Univ Puerto Rico, Dept Biol, Rio Piedras, PR 00931 USA. RP Herre, EA (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 44 TC 434 Z9 466 U1 33 U2 226 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 FEB PY 1999 VL 14 IS 2 BP 49 EP 53 DI 10.1016/S0169-5347(98)01529-8 PG 5 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 180ZY UT WOS:000079417200005 ER PT J AU Jackson, JBC Cheetham, AH AF Jackson, JBC Cheetham, AH TI Tempo and mode of speciation in the sea SO TRENDS IN ECOLOGY & EVOLUTION LA English DT Editorial Material ID MORPHOLOGICAL VARIATION; EVOLUTIONARY STASIS; CRYPTIC SPECIATION; LARVAL ECOLOGY; NEOGENE; GASTROPODS; MACROEVOLUTION; FORAMINIFERA; GLOBOCONELLA; ANAGENESIS AB The theory of punctuated equilibria proposed that most fossil species exhibit morphological stasis for millions of years between geologically instantaneous shifts in morphology associated with splitting of lineages by allopatric speciation. The theory initially spawned more rhetoric than data, but the few sufficiently detailed studies now available generally support the punctuated pattern. The realities of punctuation and stasis need to be better incorporated into evolutionary studies. Punctuated speciation does not contradict conventional neodarwinian mechanisms, but it does constrain the range of probable evolutionary scenarios for speciation, evolution of life histories and macroevolutionary trends. C1 Smithsonian Trop Res Inst, Ctr Trop Paleoecol & Archeol, Balboa, Panama. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. RP Jackson, JBC (reprint author), Smithsonian Trop Res Inst, Ctr Trop Paleoecol & Archeol, Box 2072, Balboa, Panama. NR 50 TC 82 Z9 84 U1 1 U2 33 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 FEB PY 1999 VL 14 IS 2 BP 72 EP 77 DI 10.1016/S0169-5347(98)01504-3 PG 6 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 180ZY UT WOS:000079417200017 ER PT J AU Clark, ME Wolcott, TG Wolcott, DL Hines, AH AF Clark, ME Wolcott, TG Wolcott, DL Hines, AH TI Foraging and agonistic activity co-occur in free-ranging blue crabs (Callinectes sapidus): observation of animals by ultrasonic telemetry SO JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY LA English DT Article DE agonism; Callinectes sapidus; Chesapeake Bay; foraging; ultrasonic telemetry ID CHESAPEAKE BAY; MICROHABITAT SELECTION; PATTERNS; BEHAVIOR; RATHBUN; JUVENILE; PREY; SUBESTUARY; PREDATION; ABUNDANCE AB To define the temporal and spatial patterns of agonism and foraging activity in blue crabs (Callinectes sapidus), we monitored five free-ranging animals in the Rhode River subestuary of the central Chesapeake Bay by ultrasonic telemetry during the summers of 1991-93, The interdependence between the two activities was of special interest. High crab densities have been associated with more frequent aggressive interactions and decreased foraging success in previous laboratory studies. High crab population density is correlated with increased frequency of aggression-related injury (autotomy) and cannibalism in the field. Consequently, we predicted that as crabs aggregate to clam patches during feeding periods in the field, the level of aggressive interactions would increase. In early trials, we collected data on location and agonistic activity (the stereotypical spreading of the chelae in the 'meral spread' threat display) of crabs moving freely in the estuary by using single-channel telemetry transmitters. With subsequent technological advancements, we received simultaneous data on agonism and feeding. Crabs exhibited a diel pattern of agonism with peaks in threat display occurring in mornings and sometimes in evenings. Crabs fitted with single-channel telemetry transmitters were observed interacting aggressively most often at times previously identified as feeding periods, although the highest levels of agonism came slightly later than periods associated with the highest levels of feeding. Simultaneous telemetry of the two behaviors indicated that periods of increased agonism and feeding overlapped. Feeding activity tended to wane as threat activity increased, consistent with the hypothesis that aggressive interference impairs foraging. (C) 1999 Elsevier Science BN. All rights reserved. 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, 5101 Belgrave Circle, Wilmington, NC 28403 USA. NR 51 TC 60 Z9 63 U1 2 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0981 J9 J EXP MAR BIOL ECOL JI J. Exp. Mar. Biol. Ecol. PD JAN 31 PY 1999 VL 233 IS 1 BP 143 EP 160 DI 10.1016/S0022-0981(98)00129-4 PG 18 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 159XY UT WOS:000078201700009 ER PT J AU Campbell, BA Campbell, DB DeVries, CH AF Campbell, BA Campbell, DB DeVries, CH TI Surface processes in the Venus highlands: Results from analysis of Magellan and Arecibo data SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID WESTERN EISTLA REGIO; BETA-REGIO; VOLCANIC ACTIVITY; ISHTAR-TERRA; RADAR; GEOLOGY; EMISSIVITY; BACKSCATTER; SCATTERING; TECTONICS AB The highlands of Venus are characterized by an altitude-dependent change in radar backscatter and microwave emissivity, likely produced by surface-atmosphere weathering reactions. We analyzed Magellan and Arecibo data for these regions to study the roughness of the surface, lower radar-backscatter areas at the highest elevations, and possible causes for areas of anomalous behavior in Maxwell Montes. Arecibo data show that circular and linear radar polarization ratios rise with decreasing emissivity and increasing Fresnel reflectivity, supporting the hypothesis that surface scattering dominates the return from the highlands. The maximum values of these polarization ratios are consistent with a significant component of multiple-bounce scattering. We calibrated the Arecibo backscatter values using areas of overlap with Magellan coverage, and found that the echo at high incidence angles (up to 70 degrees) from the highlands is lower than expected for a predominantly diffuse scattering regime. This behavior may be due to geometric effects in multiple scattering from surface rocks, but further modeling is required. Areas of lower radar backscatter above an upper critical elevation are found to be generally consistent across the equatorial highlands, with the shift in microwave properties occurring over as little as 500 m of elevation. These surfaces are not simply characterized, however, by the absence of a highly reflective component. Surface morphology and radar-scattering properties suggest that a mantling deposit forms at the highest elevations, most likely by in situ erosion of the original rock. In Ovda Regio, this process mantles or has removed surface festoon structure at the 1- to 10-m scale, implying a significant depth for the weathered layer. Similar radar-dark areas occur in Maxwell Montes but are apparently unrelated to the current topography of the region. Possible reasons for these observations include mass wasting from areas of steep slopes, compositional or age differences within the montes, vertical tectonic shifts of relict contacts, local topographic effects on surface temperature, or errors in the Magellan topography data in the rugged terrain. While there is evidence for some of these effects in the existing data, no single model at present appears to satisfy all occurrences of high-altitude, radar-dark terrain. New measurements of the surface and lower atmosphere chemistry of Venus are needed to further refine these conclusions. C1 Smithsonian Inst, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. Cornell Univ, Natl Astron & Ionosphere Ctr, Ithaca, NY 14853 USA. Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA. RP Campbell, BA (reprint author), Smithsonian Inst, Ctr Earth & Planetary Studies, MRC 315, Washington, DC 20560 USA. NR 45 TC 11 Z9 11 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD JAN 25 PY 1999 VL 104 IS E1 BP 1897 EP 1916 DI 10.1029/1998JE900022 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 161JJ UT WOS:000078285200006 ER PT J AU Hartmann, JM Bouanich, JP Jucks, KW Blanquet, G Walrand, J Bermejo, D Domenech, JL Lacome, N AF Hartmann, JM Bouanich, JP Jucks, KW Blanquet, G Walrand, J Bermejo, D Domenech, JL Lacome, N TI Line-mixing effects in N2O Q branches: Model, laboratory, and atmospheric spectra SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CARBON-DIOXIDE; NITROUS-OXIDE; BAND; (CH4)-C-12; PRESSURE; NUMBER; CO2 AB A model based on the energy corrected sudden approximation is used in order to account for line-mixing effects in N2O Q branches of Sigma <-> Pi bands. The performance of this theoretical approach is demonstrated by comparisons with many (about 70) N2O-N-2 and N2O-O-2 laboratory spectra recorded in the 5 and 17 mu m regions by three instrument setups; the Q branches of the 2 nu(2)(0e) - nu(2)(1f) (near 579.3 cm(-1)), nu(2) (near 588.8 cm(-1)), and nu(2) + nu(3) (near 2798.3 cm(-1)) bands are investigated for different pressures (0.1-2.0 atm) and temperatures (200-300 K). The model is used to generate a set of line-mixing parameters for the calculation of the absorption by the nu(2) Q branch under atmospheric conditions. These data are tested by comparisons between computed stratospheric emissions and values measured using a balloon-borne high resolution Fourier transform instrument. The results confirm the need to account for the effects of line mixing and demonstrate the capability of the model to represent the N2O absorption in a region which can be used for the retrieval of N2O5 mixing ratios. (C) 1999 American Institute of Physics. [S0021-9606(99)01304-5]. C1 Univ Paris Sud, Lab Phys Mol & Applicat, F-91405 Orsay, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Fac Univ Notre Dame Paix, Lab Spect Mol, B-5000 Namur, Belgium. CSIC, Inst Estructura Mat, E-28006 Madrid, Spain. Univ Paris 06, CNRS, UMR 7614, Lab Spect Mol, F-75252 Paris 05, France. CNRS, UPR 1580, LADIR, F-94320 Thiais, France. RP Hartmann, JM (reprint author), Univ Paris Sud, Lab Phys Mol & Applicat, Bat 350, F-91405 Orsay, France. RI Lacome, Nelly/A-7043-2008 NR 26 TC 20 Z9 20 U1 0 U2 3 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 22 PY 1999 VL 110 IS 4 BP 1959 EP 1968 DI 10.1063/1.477862 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 156ZU UT WOS:000078034900015 ER PT J AU Hubbell, SP Foster, RB O'Brien, ST Harms, KE Condit, R Wechsler, B Wright, SJ de Lao, SL AF Hubbell, SP Foster, RB O'Brien, ST Harms, KE Condit, R Wechsler, B Wright, SJ de Lao, SL TI Light-gap disturbances, recruitment limitation, and tree diversity in a neotropical forest SO SCIENCE LA English DT Article ID TROPICAL RAIN FORESTS; SPECIES RICHNESS; CANOPY; HETEROGENEITY; SURVIVAL; HISTORY; GROWTH; PLANTS AB Light gap disturbances have been postulated to play a major role in maintaining tree diversity in species-rich tropical forests. This hypothesis was tested in more than 1200 gaps in a tropical forest in Panama over a 13-year period. Caps increased seedling establishment and sapling densities, but this effect was nonspecific and broad-spectrum, and species richness per stem was identical in gaps and in nongap control sites. Spatial and temporal variation in the gap disturbance regime did not explain variation in species richness. The species composition of gaps was unpredictable even for pioneer tree species. Strong recruitment limitation appears to decouple the gap disturbance regime from control of tree diversity in this tropical forest. C1 Princeton Univ, Dept Ecol & Evolut Biol, Princeton, NJ 08544 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Hubbell, SP (reprint author), Princeton Univ, Dept Ecol & Evolut Biol, Princeton, NJ 08544 USA. EM shubbell@princeton.edu RI Wright, Stuart/M-3311-2013 OI Wright, Stuart/0000-0003-4260-5676 NR 39 TC 762 Z9 856 U1 20 U2 208 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 JAN 22 PY 1999 VL 283 IS 5401 BP 554 EP 557 DI 10.1126/science.283.5401.554 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 159YM UT WOS:000078203300042 ER PT J AU Jones, C Forman, W AF Jones, C Forman, W TI Einstein observatory images of clusters of galaxies SO ASTROPHYSICAL JOURNAL LA English DT Review DE galaxies : clusters : general; intergalactic medium; surveys; X-rays : galaxies ID X-RAY-CLUSTERS; COLD DARK-MATTER; ABELL CLUSTERS; RICH CLUSTERS; COMA CLUSTER; VELOCITY DISPERSIONS; DYNAMICAL EVOLUTION; INTRACLUSTER MEDIUM; EXOSAT OBSERVATIONS; LARGE-SCALE AB We present the X-ray characteristics of a sample of 368 clusters of galaxies with redshifts less than 0.2 observed with the Einstein Imaging Proportional Counter. For each cluster, we measure the 0.5-4.5 keV counting rate and compute the 0.5-4.5 keV source luminosity, as well as the bolometric luminosity within fixed metric radii. We detect 85% of Abell clusters with z < 0.1, demonstrating that the large majority of these optically selected clusters are not the results of chance superpositions. For 163 clusters, we measure their X-ray surface brightness profiles and determine their core radii. For similar to 230 clusters, we then use either our measured core radii and beta values, or mean values derived for this sample, to measure central gas densities and gas masses. We use estimated or measured duster gas temperatures, along with the derived gas-density profiles, to estimate total cluster masses, under the assumptions that the gas is isothermal and in hydrostatic equilibrium. We also present contour plots of the X-ray emission, which we use to classify the cluster morphology. We find the percentage of clusters with substructure in their X-ray images is about 40%, with no significant change in this percentage as a function of X-ray luminosity. This implies that a large fraction of all present epoch clusters are still undergoing subcluster mergers. Based on our analysis of surface brightness profiles, we find that most clusters have core radii in the range from 0.1 to 0.3 Mpc (for H-0 = 50 km s(-1) Mpc(-1)), with more massive "single" clusters having larger core radii. The beta values determined from the slope of the surface brightness profiles fall in the narrow range from 0.4 to 0.8, with beta values increasing with cluster gas temperatures. No change in the value of beta is found in the surface brightness profiles for individual clusters as a function of distance from the duster center. We compare the beta values derived from the surface brightness profiles with the corresponding a values calculated from the gas temperatures and cluster velocity dispersions. We argue that much of the discrepancy between the values of beta derived from these two methods results from overestimates of the cluster velocity dispersion due to duster substructure. Finally, we compare the gas mass to the cluster virial mass and find, for an isothermal gas, that, within a fixed metric radius of 1 Mpc, the gas mass fraction increases as a function of X-ray luminosity from 10% to 20% of the total cluster mass. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Jones, C (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM cjf@cfa.harvard.edu; wrf@cfa.harvard.edu NR 105 TC 206 Z9 208 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 1999 VL 511 IS 1 BP 65 EP 83 DI 10.1086/306646 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NL UT WOS:000079157900007 ER PT J AU Krennrich, F Biller, SD Bond, IH Boyle, PJ Bradbury, SM Breslin, AC Buckley, JH Burdett, AM Gordo, JB Carter-Lewis, DA Catanese, M Cawley, MF Fegan, DJ Finley, JP Gaidos, JA Hall, T Hillas, AM Lamb, RC Lessard, RW Masterson, C McEnery, JE Mohanty, G Moriarty, P Quinn, J Rodgers, AJ Rose, HJ Samuelson, FW Sembroski, GH Srinivasan, R Vassiliev, VV Weekes, TC AF Krennrich, F Biller, SD Bond, IH Boyle, PJ Bradbury, SM Breslin, AC Buckley, JH Burdett, AM Gordo, JB Carter-Lewis, DA Catanese, M Cawley, MF Fegan, DJ Finley, JP Gaidos, JA Hall, T Hillas, AM Lamb, RC Lessard, RW Masterson, C McEnery, JE Mohanty, G Moriarty, P Quinn, J Rodgers, AJ Rose, HJ Samuelson, FW Sembroski, GH Srinivasan, R Vassiliev, VV Weekes, TC TI Measurement of the multi-TeV gamma-ray flare spectra of Markarian 421 and Markarian 501 SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL Lacertae objects : individual (Markarian 421, Markarian 501); galaxies : active; gamma rays : observations ID ACTIVE GALAXY MARKARIAN-421; RADIATION; PHOTONS AB The energy spectrum of Markarian 421 in flaring states has been measured from 0.3 to 10 TeV using both small and large zenith angle observations with the Whipple Observatory 10 m imaging telescope. The large zenith angle technique is useful for extending spectra to high energies, and the extraction of spectra with this technique is discussed. The resulting spectrum of Markarian 421 is fitted reasonably well by a simple power law: J(E)= E-2.54+/-0.03+/-0.10 photons m(-1) s(-1) TeV-1, where the first set of errors is statistical and the second set is systematic. This is in contrast to our recently reported spectrum of Markarian 501, which over a similar energy range has substantial curvature. The differences in TeV energy spectra of gamma-ray blazars reflect both the physics of the gamma-ray production mechanism and possibly differential absorption effects at the source or in the intergalactic medium. Since Markarian 421 and Markarian 501 have almost the same redshift (0.031 and 0.033, respectively), the difference in their energy spectra must be intrinsic to the sources and not due to intergalactic absorption, assuming the intergalactic infrared background is uniform. C1 Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Univ Oxford, Dept Phys, Oxford, England. Univ Leeds, Dept Phys, Leeds LS2 9JT, W Yorkshire, England. Univ Coll Dublin, Expt Phys Dept, Dublin 4, Ireland. Washington Univ, Dept Phys, St Louis, MO 63130 USA. Natl Univ Ireland, Dept Phys, Maynooth, Kildare, Ireland. Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. CALTECH, Space Radiat Lab, Pasadena, CA 91125 USA. Galway Mayo Inst Technol, Sch Sci, Galway, Ireland. Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. RP Krennrich, F (reprint author), Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. NR 37 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 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 1999 VL 511 IS 1 BP 149 EP 156 DI 10.1086/306677 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NL UT WOS:000079157900014 ER PT J AU Williams, JP Myers, PC AF Williams, JP Myers, PC TI A survey for inward motions in the dense gas around young stellar clusters SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : kinematics and dynamics; ISM : molecules; open clusters and associations : general; stars : formation ID MOLECULAR CLOUD CORES; STAR FORMATION; MULTIPOLAR OUTFLOW; NONTHERMAL MOTIONS; L1641 REGION; CEPHEUS-A; OBJECTS; COLLAPSE; IRAS-20050+2720; IRAS-16293-2422 AB We report the results of a spectroscopic search for inward motions of the dense gas around 19 young stellar clusters. Single point observations of CS(2-1) and N2H+(1-0) were made using the Haystack 37 m telescope at 21 " resolution, and CS(2-1) and (CS)-S-34(2-1) maps were made using the FCRAO 14 m telescope at 50 " resolution. Strong, spatially extended CS self-absorption is seen in Mon OB1-D, IRAS 20050+2720, and Cepheus A, which indicates that these sources are good candidates for follow-up observations of kinematic structure. In Cepheus A, in particular, we identify a region that shows inward motions over a region greater than or similar to 0.2 pc in extent, which suggests that models of core collapse should take into account the turbulent motions in these sources. We use the normalized velocity difference, delta v = [v(thick)- v(thin)]/Delta v(thin), between the optically thick (CS) and thin (N2H+ or (CS)-S-34) lines to quantify the relative motions between the forward and central layers of dense gas. The average value of this velocity difference is not significantly different from zero for either data set, and there is no correlation with the source bolometric temperature as determined from IRAS flux measurements. Thus this cluster sample has no significant excess of sources with inward motions, unlike the samples of individual YSOs recently reported by Gregerson et al. and Mardones et al. The lower incidence of high absolute values of delta v in our sample can be attributed to a lower optical depth in the CS line due to the greater distance, and therefore poorer linear resolution, of the sources here, and to the higher kinetic and excitation temperatures in these more massive, cluster forming environments. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Williams, JP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Williams, Jonathan/B-1643-2009; OI Williams, Jonathan/0000-0001-5058-695X NR 36 TC 17 Z9 17 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 1999 VL 511 IS 1 BP 208 EP 217 DI 10.1086/306657 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NL UT WOS:000079157900020 ER PT J AU Cranmer, SR Kohl, JL Noci, G Antonucci, E Tondello, G Huber, MCE Strachan, L Panasyuk, AV Gardner, LD Romoli, M Fineschi, S Dobrzycka, D Raymond, JC Nicolosi, P Siegmund, OHW Spadaro, D Benna, C Ciaravella, A Giordano, S Habbal, SR Karovska, M Li, X Martin, R Michels, JG Modigliani, A Naletto, G O'Neal, RH Pernechele, C Poletto, G Smith, PL Suleiman, RM AF Cranmer, SR Kohl, JL Noci, G Antonucci, E Tondello, G Huber, MCE Strachan, L Panasyuk, AV Gardner, LD Romoli, M Fineschi, S Dobrzycka, D Raymond, JC Nicolosi, P Siegmund, OHW Spadaro, D Benna, C Ciaravella, A Giordano, S Habbal, SR Karovska, M Li, X Martin, R Michels, JG Modigliani, A Naletto, G O'Neal, RH Pernechele, C Poletto, G Smith, PL Suleiman, RM TI An empirical model of a polar coronal hole at solar minimum SO ASTROPHYSICAL JOURNAL LA English DT Review DE line : profiles; solar wind; Sun : corona; Sun : UV radiation ID WIND ACCELERATION REGION; ALFVEN WAVES; VELOCITY DISTRIBUTIONS; PHYSICAL-PROPERTIES; TRANSITION REGION; DENSITY STRUCTURE; ELECTRON-DENSITY; STRAY-LIGHT; ENERGY-FLOW; ALPHA-LINE AB We present a comprehensive and self-consistent empirical model for several plasma parameters in the extended solar corona above a polar coronal hole. The model is derived from observations with the SOHO Ultraviolet Coronagraph Spectrometer (UVCS/SOHO) during the period between 1996 November and 1997 April. We compare observations of H I Ly alpha and O VI lambda lambda 1032, 1037 emission lines with detailed three-dimensional models of the plasma parameters and iterate for optimal consistency between measured and synthesized observable quantities. Empirical constraints are obtained for the radial and latitudinal distribution of density for electrons, H(0), and O(5+), as well as the outflow velocity and unresolved anisotropic most probable speeds for H(0) and O(5+). The electron density measured by UVCS/SOHO is consistent with previous solar minimum determinations of the white-light coronal structure; we also perform a statistical analysis of the distribution of polar plumes using a long time series. From the emission lines we find that the unexpectedly large line widths of H(0) atoms and O(5+) ions at most heights are the result of anisotropic velocity distributions. These distributions are not consistent with purely thermal motions or the expected motions from a combination of thermal and transverse wave velocities. Above 2 R(.), the observed transverse most probable speeds for O(5+) are significantly larger than the corresponding motions for H(0), and the outflow velocities of O(5+) are also significantly larger than the corresponding velocities of H(0). Also, the latitudinal dependence of intensity constrains the geometry of the wind velocity vectors, and superradial expansion is more consistent with observations than radial flow. We discuss the constraints and implications on various theoretical models of coronal heating and acceleration. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florence, I-50125 Florence, Italy. Osserv Astron Torino, I-10025 Pino Torinese, Italy. Univ Padua, I-35131 Padua, Italy. European Space Agcy, Estec, Dept Space Sci, NL-2200 AG Noordwijk, Netherlands. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Osserv Astrofis Catania, I-95125 Catania, Italy. Univ Turin, I-10125 Turin, Italy. Osserv Astron Palermo, Palermo, Italy. Inst Astrophys Spatiale, F-91405 Orsay, France. Osserv Astrofis Arcetri, I-50125 Florence, Italy. RP Cranmer, SR (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Romoli, Marco/H-6859-2012; Naletto, Giampiero/S-6329-2016; OI Naletto, Giampiero/0000-0003-2007-3138; Giordano, Silvio/0000-0002-3468-8566; pernechele, claudio/0000-0002-7752-6268 NR 111 TC 265 Z9 266 U1 2 U2 9 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 JAN 20 PY 1999 VL 511 IS 1 BP 481 EP 501 DI 10.1086/306675 PN 1 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NL UT WOS:000079157900047 ER PT J AU Barton, EJ Bromley, BC Geller, MJ AF Barton, EJ Bromley, BC Geller, MJ TI Kinematic effects of tidal interaction on galaxy rotation curves SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : interactions; galaxies : kinematics and dynamics ID BINARY GALAXIES; SPIRAL GALAXIES; SIMULATIONS; DYNAMICS; PAIRS; VELOCITY; MODELS; NGC-2207; IC-2163; TAILS AB We use self-consistent N-body models in conjunction with models of test particles moving in galaxy potentials to explore the initial effects of interactions on the rotation curves of spiral galaxies. Using nearly self-consistent disk/bulge/halo galaxy models, we simulate the first pass of galaxies on nearly parabolic orbits; we vary orbit inclinations, galaxy halo masses, and impact parameters. For each simulation, we mimic observed rotation curves of the model galaxies. Transient interaction-induced features of the curves include distinctly rising or falling profiles at large radii and pronounced bumps in the central regions. Remarkably similar features occur in our statistical sample of optical emission-line rotation curves of spiral galaxies in tight pairs and n-tuples. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. RP Barton, EJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 36 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 20 PY 1999 VL 511 IS 1 BP L25 EP L28 DI 10.1086/311830 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NM UT WOS:000079158000007 ER PT J AU Feldman, U Laming, JM Doschek, GA Warren, HP Golub, L AF Feldman, U Laming, JM Doschek, GA Warren, HP Golub, L TI On the ability of an extreme-ultraviolet multilayer normal-incidence telescope to provide temperature information for solar plasmas SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : atmosphere; Sun : flares; telescopes ID RADIATION; CORONA AB In recent years, multilayer-coated optics have been used in solar-soft X-ray and extreme-ultraviolet telescopes to record high-resolution, full Sun images. The multilayer coatings reflect efficiently over rather narrow wavelength bands that are selected to contain spectral emission lines considered to have plasma diagnostic importance for determining approximate electron temperatures. The purpose of this Letter is to discuss the effect of continuum emission on the response of multilayer passbands and the effect of this response on temperature determinations in the 4 x 10(6)-2 x 10(7) K range. Significant effects are largely confined to continuum emission from flare plasma. The flare free-free continuum in the EUV range is nearly temperature and wavelength insensitive and dominates the emission in passbands that are centered on quiet- to active-Sun coronal lines emitted by ions such as Fe IX-Fe XV. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Sachs Freeman Associates Inc, Landover, MD 20785 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Feldman, U (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 19 TC 19 Z9 19 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 1999 VL 511 IS 1 BP L61 EP L64 DI 10.1086/311835 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NM UT WOS:000079158000016 ER PT J AU Wells, JC Simbotin, I Gavrila, M AF Wells, JC Simbotin, I Gavrila, M TI Comment on "physical reality of light-induced atomic states" Reply SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Wells, JC (reprint author), Oak Ridge Natl Lab, POB 2008,MS6203, Oak Ridge, TN 37831 USA. RI Wells, Jack/D-3675-2016 OI Wells, Jack/0000-0002-5083-3030 NR 3 TC 9 Z9 9 U1 0 U2 0 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 JAN 18 PY 1999 VL 82 IS 3 BP 665 EP 665 DI 10.1103/PhysRevLett.82.665 PG 1 WC Physics, Multidisciplinary SC Physics GA 157KC UT WOS:000078059200052 ER PT J AU Balch, WM Drapeau, DT Cucci, TL Vaillancourt, RD Kilpatrick, KA Fritz, JJ AF Balch, WM Drapeau, DT Cucci, TL Vaillancourt, RD Kilpatrick, KA Fritz, JJ TI Optical backscattering by calcifying algae: Separating the contribution of particulate inorganic and organic carbon fractions SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID 1991 COCCOLITHOPHORE BLOOM; CENTRAL NORTH-ATLANTIC; CASE-I WATERS; EMILIANIA-HUXLEYI; MICROBIAL PARTICLES; RADIATIVE-TRANSFER; OCEANIC OPTICS; CHLOROPHYLL-A; LIGHT SCATTER; MODEL AB Light scattering properties of biogenic CaCO(3) particles [particulate inorganic carbon (PIC)] were determined on cultured calcifying algae and field-derived CaCO(3) particles. The particles were separated from particulate organic carbon (POC) with a flow cytometer, volume-scattering functions were measured with a laser light-scattering photometer, and particle composition was measured using atomic absorption spectrometry. Small calcite coccoliths were best sorted by gating on the ratio of horizontally polarized forward light scattering and vertically polarized forward light scattering;plated coccolithophores could be sorted by gating on side scattering and forward angle light scattering. Normalized volume-scattering functions for the culture-derived calcite particles varied by a factor of 2 for the different species. Backscattering cross sections (m(2) particle(-1)) for calcite particles varied by similar to 35 times and were generally a function of size. Backscattering efficiencies were similar to 2-4 times higher for cells with CaCO(3) than without it. CaCO(3)-specific backscattering showed much less variability across various species; the calcite-specific backscattering coefficient varied by only similar to 38% for both cultured coccolithophores and field-derived CaCO(3) particles. Organic carbon-specific backscattering of "naked" coccolithophores was highly consistent within all coccolithophores used in our experiments, as well as with values in the literature. Our results suggest that both POC and PIC can be optically estimated, the former by measuring backscattering of decalcified phytoplankton as well as their size distribution, and the latter is proportional to acid-labile backscattering. These results show the feasibility of a rapid optical technique for measuring two biogeochemically important carbon fractions in the sea. C1 Bigelow Lab Ocean Sci, W Boothbay Harbor, ME 04575 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Meteorol & Phys Oceanog, Miami, FL 33149 USA. RP Balch, WM (reprint author), Bigelow Lab Ocean Sci, W Boothbay Harbor, ME 04575 USA. NR 63 TC 43 Z9 43 U1 1 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD JAN 15 PY 1999 VL 104 IS C1 BP 1541 EP 1558 DI 10.1029/1998JC900035 PG 18 WC Oceanography SC Oceanography GA 158LE UT WOS:000078116300022 ER PT J AU Bovensmann, H Burrows, JP Buchwitz, M Frerick, J Noel, S Rozanov, VV Chance, KV Goede, APH AF Bovensmann, H Burrows, JP Buchwitz, M Frerick, J Noel, S Rozanov, VV Chance, KV Goede, APH TI SCIAMACHY: Mission objectives and measurement modes SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article; Proceedings Paper CT Conference on Global Measurement Systems for Atmospheric Composition CY MAY, 1997 CL TORONTO, CANADA SP Int Global Atmospher Chem Program, Stratospher Proc & Their Role Climate, Global Atmospher Watch, Canadian Space Agcy, Atmospher Environm Serv ID SOLAR MESOSPHERE EXPLORER; NITRIC-OXIDE; STRATOSPHERIC AEROSOL; OZONE; SATELLITE; SPECTROMETER; ABSORPTION; ULTRAVIOLET; CALIBRATION; ATMOSPHERE AB SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography) is a spectrometer designed to measure sunlight transmitted, reflected, and scattered by the earth's atmosphere or surface in the ultraviolet, visible, and near-infrared wavelength region (240-2380 nm) at moderate spectral resolution (0.2-1.5 nm, lambda/Delta lambda approximate to 1000-10000). SCIAMACHY will measure the earthshine radiance in limb and nadir viewing geometries and solar or lunar light transmitted through the atmosphere observed in occultation. The extraterrestrial solar irradiance and lunar radiance will be determined from observations of the sun and the moon above the atmosphere. The absorption, reflection, and scattering behavior of the atmosphere and the earth's surface is determined from comparison of earthshine radiance and solar irradiance. Inversion of the ratio of earthshine radiance and solar irradiance yields information about the amounts and distribution of important atmospheric constituents and the spectral reflectance (or albedo) of the earth's surface. SCIAMACHY was conceived to improve our knowledge and understanding of a variety of issues of importance for the chemistry and physics of the earth's atmosphere (troposphere, stratosphere, and mesosphere) and potential changes resulting from either increasing anthropogenic activity or the variability of natural phenomena. Topics of relevance for SCIAMACHY are tropospheric pollution arising from industrial activity and biomass burning, troposphere-stratosphere exchange processes, stratospheric ozone chemistry focusing on the understanding of the ozone depletion in polar regions as well as in midlatitudes, and solar variability and special events such as volcanic eruptions, and related regional and global phenomena. Inversion of the SCIAMACHY measurements enables the amounts and distribution of the atmospheric constituents O(3), O(2), O(2)(Delta'), O(4), BrO, OCIO, ClO, SO(2), H(2)CO, NO, NO(2), NO(3), CO, CO(2), CH(4), H(2)O, N(2)O, and aerosol, as well as knowledge about the parameters pressure p, temperature T, radiation held, cloud cover, cloud-top height, and surface spectral reflectance to be determined. A special feature of SCIAMACHY is the combined limb-nadir measurement mode. The inversion of the combination of limb and nadir measurements will enable tropospheric column amounts of O(3), NO(2), BrO, CO, CH(4), H(2)O, N(2)O, SO(2), and H(2)CO to be determined. C1 Univ Bremen, Inst Environm Phys, FB1, D-28334 Bremen, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. SRON Ruimetonderzoek, Utrecht, Netherlands. RP Bovensmann, H (reprint author), Univ Bremen, Inst Environm Phys, FB1, POB 33 04 40, D-28334 Bremen, Germany. EM bov@gome5.physik.uni-bremen.de RI Buchwitz, Michael/G-1510-2011; Bovensmann, Heinrich/P-4135-2016; Burrows, John/B-6199-2014; OI Bovensmann, Heinrich/0000-0001-8882-4108; Burrows, John/0000-0002-6821-5580; Chance, Kelly/0000-0002-7339-7577 NR 64 TC 905 Z9 953 U1 9 U2 76 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD JAN 15 PY 1999 VL 56 IS 2 BP 127 EP 150 DI 10.1175/1520-0469(1999)056<0127:SMOAMM>2.0.CO;2 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 160JC UT WOS:000078226000002 ER PT J AU Kochanek, CS Falco, EE Munoz, JA AF Kochanek, CS Falco, EE Munoz, JA TI Why quasar pairs are binary quasars and not gravitational lenses SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : interactions; gravitational lensing; quasars : general ID LUMINOSITY FUNCTION; REDSHIFT SURVEY; DARK-MATTER; BLACK-HOLES; GALAXIES; EVOLUTION; CANDIDATE; POPULATION; DISCOVERY; OBJECTS AB We use simple comparisons of the optical and radio properties of the wide separation (3 " < Delta theta < 10 ") quasar pairs to demonstrate that they are binary quasars rather than gravitational lenses. The most likely model is that all of the pairs are binary quasars, with a one-sided 2 sigma (1 sigma) upper limit of 22% (8%) on the lens fraction. Simple models for the expected enhancement of quasar activity during galaxy mergers that are consistent with the enhancement observed at low redshift can explain the incidence, separations, redshifts, velocity differences, and radio properties of the binary quasar population. Only a modest fraction (less than or similar to 5%) of all quasar activity need be associated with galaxy mergers to explain the binary quasars. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kochanek, CS (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM ckochanek@cfa.harvard.edu; falco@cfa.harvard.edu; jlehar@cfa.harvard.edu NR 60 TC 81 Z9 83 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 1999 VL 510 IS 2 BP 590 EP 596 DI 10.1086/306594 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NJ UT WOS:000079157600007 ER PT J AU Ho, LC AF Ho, LC TI What powers the compact radio emission in nearby elliptical and S0 galaxies? SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : elliptical and lenticular, cD; galaxies : nuclei; galaxies : Seyfert; radiation mechanisms : nonthermal; radio continuum : galaxies ID DWARF SEYFERT NUCLEI; ACTIVE GALACTIC NUCLEI; JET-INDUCED VELOCITIES; BRIGHT E/S0 GALAXIES; SPIRAL GALAXIES; ASTRONOMICAL DATA; STATISTICAL-METHODS; CONTINUUM SOURCES; STAR FORMATION; LOW-LUMINOSITY AB Many nearby early-type (elliptical and S0) galaxies contain weak (millijansky level) nuclear radio sources on scales of a few hundred parsecs or less. The origin of the radio emission, however, has remained unclear, especially in volume-limited samples that select intrinsically less luminous galaxies. Both active galactic nuclei and nuclear star formation have been suggested as possible mechanisms for producing the radio emission. This paper utilizes optical spectroscopic information to address this issue. A substantial fraction of the early-type galaxies surveyed with the Very Large Array by Wrobel & Heeschen exhibits detectable optical emission lines in their nuclei down to very sensitive limits. Comparison of the observed radio continuum power with that expected from the thermal gas traced by the optical emission lines implies that the bulk of the radio emission is nonthermal. Both the incidence and the strength of optical line emission correlate with the radio power. At a fixed line luminosity, ellipticals have stronger radio cores than S0s. The relation between radio power and line emission observed in this sample is consistent with the low-luminosity extension of similar relations seen in classical radio galaxies and luminous Seyfert nuclei. A plausible interpretation of this result is that the weak nuclear sources in nearby early-type galaxies are the low-luminosity counterparts of more powerful AGNs. The spectroscopic evidence supports this picture. Most of the emission-line objects are optically classified as Seyfert nuclei or low-ionization nuclear emission-line regions (LINERs), the majority of which are likely to be accretion-powered sources. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ho, LC (reprint author), Carnegie Inst Washington Observ, 813 Santa Barbara St, Pasadena, CA 91101 USA. NR 44 TC 27 Z9 27 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 JAN 10 PY 1999 VL 510 IS 2 BP 631 EP 636 DI 10.1086/306597 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NJ UT WOS:000079157600012 ER PT J AU Peterson, BM Barth, AJ Berlind, P Bertram, R Bischoff, K Bochkarev, NG Burenkov, AN Cheng, FZ Dietrich, M Filippenko, AV Giannuzzo, E Ho, LC Huchra, JP Hunley, J Kaspi, S Kollatschny, W Leonard, DC Malkov, YF Matheson, T Mignoli, M Nelson, B Papaderos, P Peters, J Pogge, RW Pronik, VI Sergeev, SG Sergeeva, EA Shapovalova, AI Stirpe, GM Tokarz, S Wagner, RM Wanders, I Wei, JY Wilkes, BJ Wu, H Xue, SJ Zou, ZL AF Peterson, BM Barth, AJ Berlind, P Bertram, R Bischoff, K Bochkarev, NG Burenkov, AN Cheng, FZ Dietrich, M Filippenko, AV Giannuzzo, E Ho, LC Huchra, JP Hunley, J Kaspi, S Kollatschny, W Leonard, DC Malkov, YF Matheson, T Mignoli, M Nelson, B Papaderos, P Peters, J Pogge, RW Pronik, VI Sergeev, SG Sergeeva, EA Shapovalova, AI Stirpe, GM Tokarz, S Wagner, RM Wanders, I Wei, JY Wilkes, BJ Wu, H Xue, SJ Zou, ZL TI Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. XV. Long-term optical monitoring of NGC 5548 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (NGC 5548); galaxies : nuclei; galaxies : Seyfert ID SEYFERT-GALAXY NGC-5548; ULTRAVIOLET-SPECTRUM; FE-II; EMISSION; VARIABILITY; WAVELENGTHS; EVOLUTION; ACCURACY; QUASARS AB We present the results of 3 yr of ground-based observations of the Seyfert 1 galaxy NGC 5548, which, combined with previously reported data, yield optical continuum and broad-line H beta light curves for a total of 8 yr. The light curves consist of over 800 points, with a typical spacing of a few days between observations. During this 8 yr period, the nuclear continuum has varied by more than a factor of 7, and the H beta emission line has varied by a factor of nearly 6. The H beta emission line responds to continuum variations with a time delay or lag of similar to 10-20 days, the precise value varying somewhat from year to year. We find some indications that the lag varies with continuum flux in the sense that the lag is larger when the source is brighter. C1 Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Lowell Observ, Flagstaff, AZ 86001 USA. Univ Sternwarte Gottingen, D-37083 Gottingen, Germany. Univ Moscow, Sternberg Astron Inst, Moscow 119899, Russia. Russian Acad Sci, Special Astrophys Observ, Nizhnii Arkhyz 357147, Russia. Univ Sci & Technol China, Ctr Astrophys, Hefei 230026, Anhui, Peoples R China. Landessternwarte Heidelberg, D-69117 Heidelberg, Germany. Univ Hertfordshire, Dept Phys Sci, Hatfield AL10 9AB, Herts, England. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Wise Observ, IL-69978 Tel Aviv, Israel. Crimean Astrophys Observ, UA-334413 Nauchnyi, Ukraine. Osservatorio Astron Bologna, I-40126 Bologna, Italy. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90024 USA. Chinese Acad Sci, Beijing Astron Observ, Beijing 100080, Peoples R China. RP Peterson, BM (reprint author), Ohio State Univ, Dept Astron, 174 W 18Th Ave, Columbus, OH 43210 USA. EM peterson@astronomy.ohio-state.edu; abarth@astro.berkeley.edu; pberlind@cfa.harvard.edu; rayb@lowell.edu; bischoff@uni-sw.gwdg.de; boch@astronomy.msk.su; ashap@sao.ru; fzhen@ustc.edu.cn; mdietric@mail.lsw.uni-heidelberg.de; afilippenko@astro.berkeley.edu; ester@star.herts.ac.uk; lho@cfa.harvard.edu; huchra@cfa.harvard.edu; jhunley@elmers.com; shai@wise.tau.ac.il; wkollat@gwdg.de; dleonard@astro.berkeley.edu; tmatheson@astro.berkeley.edu; mignoli@astbo3.bo.astro.it; nelson@astro.ucla.edu; papade@uni-sw.gwdg.de; pogge@astronomy.ohio-state.edu; vpronik@crao.crimea.ua; sergeev@crao.crimea.ua; ashap@sao.ru; stirpe@astbo3.bo.astro.it; selena@crao.crimea.ua; rmw@altair.lowell.edu; xenu@xs4all.nl; belinda@cfa.harvard.edu; wu@bac.pku.edu.cn; zouzl@sun.ihep.ac.cn RI Papaderos, Polychronis/M-4206-2013; Stirpe, Giovanna/O-9393-2015; Mignoli, Marco/O-9426-2015; OI Papaderos, Polychronis/0000-0002-3733-8174; Stirpe, Giovanna/0000-0002-3702-8731; Mignoli, Marco/0000-0002-9087-2835; Wilkes, Belinda/0000-0003-1809-2364 NR 33 TC 63 Z9 63 U1 0 U2 3 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 JAN 10 PY 1999 VL 510 IS 2 BP 659 EP 668 DI 10.1086/306604 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NJ UT WOS:000079157600015 ER PT J AU Grindlay, JE AF Grindlay, JE TI Fast X-ray transients and gamma-ray bursts: Constraints on beaming SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; X-rays : bursts ID 28 FEBRUARY 1997; SKY SURVEY; MONITOR AB The detection of X-ray afterglows of gamma-ray burst (GRB) sources has enabled the optical discovery that GRBs are at cosmological distances, which confirms that the enormous luminosities required must produce a relativistically expanding fireball. It is not yet clear whether this expansion is quasi-spherical or beamed, or if the beaming differs between the prompt GRB and afterglow, although the differences for both source emission and population models are profound. We show that relative beaming (prompt vs. afterglow) may be constrained by analysis of the "fast transient" X-ray sources cataloged by Pye & McHardy from the Ariel 5 survey as well as several other surveys (e.g., HEAO I experiments A-1/A-2). After removing contamination from likely stellar transients, and scaling from X-ray/gamma-ray fluence ratios recently derived from Ginga and BeppoSAX, approximately half of the sources were possible prompt emission or afterglows from GRBs with gamma-ray fluence of greater than or similar to 1.2 x 10(-5) ergs cm(-2). Since the rate of these candidate afterglow events, 0.15 day(-1), is consistent with the BATSE log N-log S distribution, no difference in prompt versus afterglow beaming is required. However, more sensitive X-ray monitors or hard X-ray imaging surveys, with better temporal and spatial resolution, could provide strong constraints on GRBs and beaming. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Grindlay, JE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 25 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 10 PY 1999 VL 510 IS 2 BP 710 EP 714 DI 10.1086/306617 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NJ UT WOS:000079157600019 ER PT J AU Stassun, K Wood, K AF Stassun, K Wood, K TI Magnetic accretion and photopolarimetric variability in classical T Tauri stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; polarization; radiative transfer; stars : pre-main-sequence; stars : rotation; stars : spots ID YOUNG STELLAR OBJECTS; MAGNETOCENTRIFUGALLY DRIVEN FLOWS; MODEL SCATTERING ENVELOPES; MAGNETOSPHERIC ACCRETION; CIRCUMSTELLAR DISKS; LINEAR-POLARIZATION; OPTICAL-PROPERTIES; SILICATE GRAINS; NEUTRON STARS; ROTATION AB We employ a Monte Carlo radiation transfer code to investigate the multiwavelength photopolarimetric variability arising from a spotted T Tauri star surrounded by a dusty circumstellar disk. Our aim is to assess the ability of the magnetic accretion model to explain the observed photopolarimetric variability of classical T Tauri stars and to identify potentially useful observational diagnostics of T Tauri star/disk/spot parameters. We model a range of spot sizes, spot latitudes, inner disk truncation radii, and system inclination angles, as well as multiple disk and spot geometries. We find that the amplitude, morphology, and wavelength-dependence of the photopolarimetric variability predicted by our models are generally consistent with existing observations; a flared disk geometry is required to reproduce the largest observed polarization levels and variations. Our models can further explain stochastic polarimetric variability if unsteady accretion is invoked, in which case irregular (but correlated) photometric variability is predicted, in agreement with observations. We find that variability in percent polarization is by itself an unreliable diagnostic, because certain system geometries do clot produce any variability in linear polarization (contrary to the commonly held notion that hot spots will necessarily produce periodic polarimetric variability). Observations of variability in polarization position angle, however, could provide useful constraints on system inclination. The observation of wavelength-dependent polarization position angles,attributed by some to interstellar effects, is naturally explained by our models. Certain system geometries yield peculiar photometric light curve morphologies, the observation of which could also serve to constrain system inclination. We do not find useful diagnostics of disk truncation radius, nor do we find significant differences when we model the spots as rings. We also investigate the reliability of modeling spot parameters via analytic fits to multiband photometric variations. T;Ve find that commonly used analytic models consistently recover input model parameters but that inferred spot temperatures are more sensitive to uncertainties in the photometric data than previous modeling would suggest. C1 Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Stassun, K (reprint author), Univ Wisconsin, Dept Astron, 475 N Charter St, Madison, WI 53706 USA. EM keivan@astro.wisc.edu; kenny@claymore.harvard.edu NR 46 TC 24 Z9 24 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 1999 VL 510 IS 2 BP 892 EP 904 DI 10.1086/306606 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NJ UT WOS:000079157600035 ER PT J AU Katsova, MM Drake, JJ Livshits, MA AF Katsova, MM Drake, JJ Livshits, MA TI New insights into the large 1992 July 15-17 flare on AU Microscopii: The first detection of posteruptive energy release on a red dwarf star SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : flare; stars : individual (AU Microscopii); ultraviolet : stars ID EXTREME-ULTRAVIOLET-EXPLORER; CORONAL MASS EJECTION; X-RAY-EMISSION; STELLAR FLARES; MAGNETIC RECONNECTION; SOLAR-FLARES; AR LACERTAE; PLASMA; QUIESCENT; SPECTRUM AB Extreme Ultraviolet Explorer (EUVE) observations of the long-duration 1992 July 15-17 flaring event on the red dwarf star AU Mic are discussed. The flare was detected in the EUVE Deep Survey (DS) Lexan/B band (65-190 Angstrom) and was made up of a large impulsive event corresponding to an increase in the extreme ultraviolet (EUV) emission by a factor of 15 relative to quiescence, followed by a slow exponential decay interspersed with another smaller impulsive event and further decay. As observed in the EUV, the flare lasted for more than half a day. A similar exponential decay of the Bur in the Fe XVIII lambda 93.9 line was detected in the EUVE short wavelength (SW) spectrometer following the first powerful impulsive phase. The flare decay in the 65-190 Angstrom band and in the Fe XVIII line during this prolonged event lasted a factor of 10 or more longer than would have been the case had the plasma cooling been due only to radiative losses at typical hare plasma densities. An analysis of the simultaneous DS Lexan/B data and the Fe XVIII line flux has allowed us to determine the approximate temporal behavior of the flaring plasma temperature (d log T/dt approximate to -0.5 day(-1)) and of the emission measure of the EUV source. The total energy emitted in the 1-2000 Angstrom range during the first 12 hours or so of the flaring event was 3 x 10(35) ergs. Solar analogs of processes providing similar long-duration soft X-ray radiation are discussed: (1) a coronal mass ejection (CME); (2) a system of giant postflare arches, which can form in powerful solar flares after a CME; (3) typical soft X-ray flaring loops. A general expression describing the energy balance in the EUV source is derived for both CMEs and giant arch systems. As a result, we conclude that the long-duration EUV emission in the AU Mic flare most resembles the solar scenario of emission from a system of giant coronal arches forming after a CME. Such a system on AU Mic would have a size of 1-2 stellar radii and would be energized by reconnection in a vertical current sheet. In this picture, a substantial part of the radiative loss is compensated for by additional postflare energy input, in a similar way as is thought to take place in the posteruptive phases of the most powerful solar flares. Apparently, we are faced here with a new kind of surface activity on late-type stars, which is intermediate between impulsive hares on red dwarf stars and the long-duration, powerful events seen on subgiant components of the RS CVn binaries. C1 Moscow MV Lomonosov State Univ, Sternberg State Astron Inst, Moscow 119899, Russia. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Russian Acad Sci, Inst Terr Magnetism Ionosphere & Radio Wave Propa, Troitsk 142092, Moscow Region, Russia. RP Katsova, MM (reprint author), Moscow MV Lomonosov State Univ, Sternberg State Astron Inst, Moscow 119899, Russia. NR 69 TC 19 Z9 19 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 JAN 10 PY 1999 VL 510 IS 2 BP 986 EP 998 DI 10.1086/306587 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NJ UT WOS:000079157600043 ER PT J AU Ciaravella, A Raymond, JC Strachan, L Thompson, BJ St Cyr, OC Gardner, L Modigliani, A Antonucci, E Kohl, J Noci, G AF Ciaravella, A Raymond, JC Strachan, L Thompson, BJ St Cyr, OC Gardner, L Modigliani, A Antonucci, E Kohl, J Noci, G TI Ultraviolet and optical observations of a coronal transient with SOHO SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona; Sun : UV radiation ID MASS EJECTIONS; SOLAR; SPECTROMETER; VELOCITY; FIELDS; LASCO; IONS AB A coronal transient was observed on 1997 March 6 at 1.6 R. over an active region on the east limb. We observed both the edge of horizontally compressed gas and the diffuse curtain of coronal material. The region was monitored for 4 hr, and the H I Ly alpha, O VI lambda lambda 1031.91, 1037.61, N V lambda lambda 1242.80, 1238.80, and O V] lambda 1218.35 lines were detected during the ejection evolution. The density, velocity, temperature, and oxygen abundance of the ejected plasma have been obtained from the observed spectra. Intermediate temperature lines of N V, O VI, and O V show a large enhancement, suggesting a quite narrow range of plasma temperature around 4 x 10(5) K. Doppler shifts of the ejected material evolve from an initial blueshift of 100 km s(-1) to a redshift of 145 km s(-1). The outflow velocity, as determined by Doppler dimming analysis of the O VI doublet, is only about 20 km s(-1). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Dipartimento Sci Fis & Astron, I-90134 Palermo, Italy. NASA, Goddard Space Flight Ctr, NRL, CPI, Greenbelt, MD 20771 USA. Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. Osserv Astron Torino, I-10125 Turin, Italy. RP Ciaravella, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Thompson, Barbara/C-9429-2012 NR 27 TC 18 Z9 18 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 JAN 10 PY 1999 VL 510 IS 2 BP 1053 EP 1063 DI 10.1086/306622 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NJ UT WOS:000079157600048 ER PT J AU Bergin, EA Neufeld, DA Melnick, GJ AF Bergin, EA Neufeld, DA Melnick, GJ TI Formation of interstellar ices behind shock waves SO ASTROPHYSICAL JOURNAL LA English DT Article DE comets : general; ISM : abundances; ISM : clouds; ISM : molecules; molecular processes; shock waves ID DISSOCIATIVE RECOMBINATION; MOLECULAR SHOCKS; DEUTERIUM; CHEMISTRY; CLOUDS; WATER; CORES; FRACTIONATION; ABUNDANCE; D/H AB We have used a coupled dynamical and chemical model to examine the chemical changes induced by the passage of an interstellar shock in well-shielded regions. Using this model, we demonstrate that the formation of H2O in a shock will be followed in tb: postshock phase by depletion of the water molecules onto the grain surfaces. To attempt to discriminate between the creation of ices behind shocks and their production by means of grain surface chemistry, we examine title deuterium chemistry of water before, during, and after a shock. We show that chemical evolution in the postshock gas can account for both the deuterium fractionation and the abundance of CO2 relative to H2O observed in interstellar and cometary ices. Given the pervasiveness of shocks and turbulent motions within molecular clouds, the model presented here offers an alternative theory to grain surface chemistry for the creation of ices in the interstellar medium, ices that may ultimately be incorporated into comets. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Bergin, EA (reprint author), Harvard Smithsonian Ctr Astrophys, MS-66,60 Garden St, Cambridge, MA 02138 USA. NR 39 TC 33 Z9 33 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 10 PY 1999 VL 510 IS 2 BP L145 EP L148 DI 10.1086/311817 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NK UT WOS:000079157700016 ER PT J AU Soon, W Frick, P Baliunas, S AF Soon, W Frick, P Baliunas, S TI Lifetime of surface features and stellar rotation: A wavelet time-frequency approach SO ASTROPHYSICAL JOURNAL LA English DT Article DE methods : numerical; stars : chromospheres; stars : rotation ID MAIN-SEQUENCE STARS; COOL STARS AB We explore subtle variations in disk-integrated measurements spanning less than or similar to 18 yr of stellar surface magnetism by using a newly developed time-frequency gapped wavelet algorithm. We present results based on analysis of the Mount Wilson Ca II H and K emission fluxes in four, magnetically active stars (HD.1835 [G2 V], HD 82885 [G8 IV-V], HD 149661 [KO V], and HD 190007 [K4 V]) and sensitivity tests using artificial data. When the wavelet basis is appropriately modified (i.e., when the time-frequency resolution is optimized), the results are consistent with the existence of spatially localized and long-lived Ca II features (assumed here as activity regions that tend to recur in narrowly confined latitude bands), especially in HD 1835 and HD 82885. This interpretation is based on the observed persistence of relatively localized Ca II wavelet power at a narrow range of rotational timescales, enduring as long as greater than or similar to 10 yr. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Inst Continuous Media Mech, Perm 614061, Russia. RP Soon, W (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Frick, Peter/D-2345-2013 NR 15 TC 16 Z9 17 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 10 PY 1999 VL 510 IS 2 BP L135 EP L138 DI 10.1086/311805 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NK UT WOS:000079157700014 ER PT J AU Gingerich, O AF Gingerich, O TI The heavens on fire: The great Leonid meteor storms 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 MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 7 PY 1999 VL 397 IS 6714 BP 33 EP 33 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 155RD UT WOS:000077959400034 ER PT J AU Thollesson, M AF Thollesson, M TI Phylogenetic analysis of Euthyneura (Gastropoda) by means of the 16S rRNA gene: use of a 'fast' gene for 'higher-level' phylogenies SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE cladistic analysis; nudibranchs; opisthobranchs; phylogenetic taxonomy ID MOLECULAR PHYLOGENY; MINIMUM-EVOLUTION; SEQUENCE-ANALYSIS; DNA-SEQUENCES; OPISTHOBRANCHIA; SYSTEMATICS; MOLLUSCA; RNA; HETEROBRANCHIA; NUDIBRANCH AB The phylogeny of Euthyneura is analysed by using DNA sequences of the mitochondrial 16S rRNA gene. Despite the common notion that this gene is too variable to provide useful information at high taxonomic levels, such as in the present study, bootstrap proportions are high for several clades in the study. This indicates that there is a useful amount of variation despite the noise due to multiple substitutions. The analyses furthermore indicate that (i) Gymnosomata (represented by Clione) is not a part of Euthyneura, but Clione forms a clade with the caenogastropods; (ii) Acteon is the sister group to the remaining euthyneuran taxa in the study; (iii) the nudibranch taxa form two clades, one comprising Dendronotoidea, Arminoidea and Aeolidoidea (together Cladobranchia) with Notaspidea (represented by Berthella) as sister group, while the fourth nudibranch taxon, Doridoidea, forms a separate clade; (iv) Cephalaspidea sensu stricto and Anaspidea form clades that are each other's sister groups (together Pleurocoela). Finally, there is no clade present in the analyses corresponding to the taxon Opisthobranchia in the traditional sense, and the use of this name is probably better abandoned altogether. C1 Univ Gothenburg, Dept Zool, SE-40530 Gothenburg, Sweden. RP Thollesson, M (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Washington, DC 20560 USA. EM thollesson@lms.si.edu NR 70 TC 55 Z9 62 U1 2 U2 7 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 EI 1471-2954 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD JAN 7 PY 1999 VL 266 IS 1414 BP 75 EP 83 DI 10.1098/rspb.1999.0606 PG 9 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 159CJ UT WOS:000078154000010 ER PT S AU Avrett, EH AF Avrett, EH BE Vial, JC KaldeichSchrumann, B TI Combined effects of mass flow and particle diffusion on the ionization structure of the solar transition region SO 8TH SOHO WORKSHOP: PLASMA DYNAMICS AND DIAGNOSTICS IN THE SOLAR TRANSITION REGION AND CORONA, PROCEEDINGS SE ESA Special Publications LA English DT Proceedings Paper CT 8th SOHO Workshop on Plasma Dynamics and Diagnostics in the Solar Transition Region and Corona CY JUN 22-25, 1999 CL PARIS, FRANCE SP European Space Agcy, NASA, CNES, CNRS, INSU, Euroconf, Inst Astrophys Spatiale, Matra Marconi Space, SCOSTEP, Univ Paris XI ID EMISSION; HELIUM; LINE AB The transition region between the top of the chromosphere (T < 10 000 K) and the lowest past of the corona (T > 100 000 K) is known to have a thickness of only a few kilometers. This is the temperature range in which there is maximum radiative cooling in the strong resonance lines of H, HeI, and HeII. The heat input that balances this radiative cooling appears to come from the low corona rather than from local mechanical heating. Detailed models of the transition region without the effects of mass flow have been published by Fontenla, Avrett, & Loeser (1993). They solved the complete set of radiative transfer, statistical equilibrium, and energy balance equations for H, HeI, and HeII, balancing the cooling due to optically thick, non-LTE radiative transitions with the heating due to the transport of energy from higher temperatures by thermal conduction and particle diffusion. The resulting theoretical models showed better agreement with observations than earlier empirical models based on local statistical equilibrium without particle diffusion. Shown here are our first results of the more complicated calculations that include the additional effects of mass flows. Here we consider mass-conserving outflow and inflow velocities having values of 1 and 5 km s(-1) in the upper transition region. The hydrogen Lyman lines are not highly sensitive to such flows, but the resonance lines of HeI and HeII show pronounced effects as a result of ionization balance changes. Outflow causes greater amounts of HeI and HeII at higher temperatures while inflow causes greater amounts of HeII and HeIII at lower temperatures, compared with zero-flow ionization equilibrium. As before, these calculations include particle diffusion, i.e., ions penetrate into nearby neutral regions and neutrals into nearby ionized regions. We find that particle diffusion remains important even for the highest flow velocities we have considered. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Avrett, EH (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM eavrett@cfa.harvard.edu NR 8 TC 2 Z9 2 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-784-4 J9 ESA SPEC PUBL PY 1999 VL 446 BP 141 EP 144 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Physics, Fluids & Plasmas SC Astronomy & Astrophysics; Geochemistry & Geophysics; Physics GA BP62N UT WOS:000085712900020 ER PT S AU Fineschi, S van Ballegoijen, A Kohl, JL AF Fineschi, S van Ballegoijen, A Kohl, JL BE Vial, JC KaldeichSchrumann, B TI Coronal magnetic field diagnostics with UV spectro-polarimetry SO 8TH SOHO WORKSHOP: PLASMA DYNAMICS AND DIAGNOSTICS IN THE SOLAR TRANSITION REGION AND CORONA, PROCEEDINGS SE ESA Special Publications LA English DT Proceedings Paper CT 8th SOHO Workshop on Plasma Dynamics and Diagnostics in the Solar Transition Region and Corona CY JUN 22-25, 1999 CL PARIS, FRANCE SP European Space Agcy, NASA, CNES, CNRS, INSU, Euroconf, Inst Astrophys Spatiale, Matra Marconi Space, SCOSTEP, Univ Paris XI DE corona; magnetic fields; polarimetry ID HYDROGEN AB In the extended corona, the state of linear polarization of ultraviolet (UV) line emission, is affected by the presence of magnetic fields. This provides a useful diagnostics of the coronal magnetic field, that, to date, is still largely unknown. The interpretation through the Hanle effect of the strength and direction of the polarization vector of the H I Lyman series lines (i.e., Ly-alpha, 1216 Angstrom, Ly-beta, 1025 Angstrom, Ly-gamma, 972 Angstrom) yields information on the vector magnetic field in corona. The polarization direction of the O VI, 1032 Angstrom, line is affected by non-radial outflow velocities of the solar wind. This may be used to obtain information on the coronal field topology. The parameter study presented here shows that the H I Lyman series lines have sensitivities to the field stregths larger than 1 gauss, at heliocentric heights comprised between 1.2 to 2 solar radii. The Advanced Solar Coronal Explorer mission, briefly described here, is designed to carry out spectro-polarimetric measurements of these UV coronal lines. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM Sfineschi@cfa.harvard.edu NR 6 TC 7 Z9 7 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-784-4 J9 ESA SPEC PUBL PY 1999 VL 446 BP 317 EP 320 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Physics, Fluids & Plasmas SC Astronomy & Astrophysics; Geochemistry & Geophysics; Physics GA BP62N UT WOS:000085712900051 ER PT S AU Eff-Darwich, A AF Eff-Darwich, A BE Wilson, A TI Helioseismic inferences on the stratification and dynamics of the solar interior SO 9TH EUROPEAN MEETING ON SOLAR PHYSICS: MAGNETIC FIELDS AND SOLAR PROCESSES, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 9th European Meeting on Solar Physics CY SEP 12-18, 1999 CL UNIV FLORENCE, FLORENCE, ITALY SP European Union, European Space Agcy, Div joint Astrophys, Solar Phys Sect, Univ Firenze, Osservatorio Astrofis Arcetri, Agenzia Spaziale Italiana, CNR, Banca Commerciale Italiana, Banca Toscana, EPS HO UNIV FLORENCE DE helioseismology ID DIFFERENTIAL ROTATION; CORE ROTATION; P-MODE; OSCILLATIONS; FREQUENCIES; CONSTRAINTS; SURFACE; FLOWS AB Small amplitude oscillations at the surface of the sun have been first observed more than 30 years ago, with amplitudes around 300 m/s and periods around five minutes. In contrast to classical variable stars where only a few set of pulsation modes are excited (like for instant Cepheids), the solar oscillation spectrum is a rich set where millions of modes are simultaneously excited and observed. This huge amount of information forms the observational basis of helioseismology which allow us to infer the properties of the sun's interior from the characteristics of its oscillations. The five-minute oscillations observed on the sun are acoustic resonant modes, namely pressure waves that propagate through the interior of the sun and are reflected near the surface by the strong density gradient, where they are observed. The frequency of any given mode is directly related to the precise stratification of the medium it samples, namely the pressure, density, temperature and chemical composition of the fraction of the solar interior where the mode amplitude is significant. Dynamical effects also modify the observed frequency, e.g. advection by rotation. Accurate measurements of a large ensemble of mode frequencies allow us to derive the internal conditions of our star. In this paper we describe the methodologies that allow us to infer the internal structure and rotation rate from helioseismic observations. We also present examples of such inferences, whose unprecedent precision imposes strong constrains on modern theoretical models of stellar structure and evolution. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Eff-Darwich, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 39 TC 0 Z9 0 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-792-5 J9 ESA SP PUBL PY 1999 VL 448 BP 21 EP 30 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP86P UT WOS:000086446800003 ER PT S AU Miralles, MP Strachan, L Gardner, LD Dobryzcka, D Ko, YK Michels, J Panasyuk, A Suleiman, R Kohl, JL AF Miralles, MP Strachan, L Gardner, LD Dobryzcka, D Ko, YK Michels, J Panasyuk, A Suleiman, R Kohl, JL BE Wilson, A TI Streamer HI Ly-alpha line profiles during the Spartan 201-05/SOHO coordinated observations SO 9TH EUROPEAN MEETING ON SOLAR PHYSICS: MAGNETIC FIELDS AND SOLAR PROCESSES, VOLS 1 AND 2 SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 9th European Meeting on Solar Physics CY SEP 12-18, 1999 CL UNIV FLORENCE, FLORENCE, ITALY SP European Union, European Space Agcy, Div joint Astrophys, Solar Phys Sect, Univ Firenze, Osservatorio Astrofis Arcetri, Agenzia Spaziale Italiana, CNR, Banca Commerciale Italiana, Banca Toscana, EPS HO UNIV FLORENCE DE solar corona; solar wind; coronal streamers; UV spectroscopy ID ULTRAVIOLET CORONAGRAPH SPECTROMETER; SOLAR-WIND; NEUTRAL HYDROGEN AB We present H I Ly-alpha observations of coronal streamers obtained by UVCS/SOHO during the coordinated observations with UVCS/Spartan on 1-3 November 1998. Two different streamer regions were observed, one relatively stable above the Northeast limb, and a post-CME streamer complex above the Southwest limb. H I Ly-alpha profiles and intensities were measured at similar to 1.5 and 2 R. in the NE streamer and its boundary regions, and also at heights ranging from 1.5 to 2.5 R. in the SW streamer complex. We analyze integrated intensities and line widths in each streamer structure. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Miralles, MP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 17 TC 1 Z9 1 U1 0 U2 1 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-792-5 J9 ESA SP PUBL PY 1999 VL 448 BP 1193 EP 1197 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP86P UT WOS:000086446800193 ER PT S AU Johnson, L Gilchrist, B Estes, RD Lorenzini, E AF Johnson, L Gilchrist, B Estes, RD Lorenzini, E BE James, HG Raitt, WJ Sultzer, MP TI Overview of future NASA tether applications SO ACTIVE EXPERIMENTS IN SPACE PLASMAS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT D0 8 Symposium of COSPAR Scientific Commission D Held at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP Int Union Radio Sci, Comm Space Res AB The groundwork has been laid for tether applications in space. NASA has developed tether technology for space applications since the 1960's. Important recent milestones include retrieval of a tether in space (TSS-1, 1992), successful deployment of a 20-km-long tether in space (SEDS-1, 1993), closed loop control of tether deployment (SEDS-2, 1994), and operation of an electrodynamic tether with tether current driven in both directions-power and thrust modes (PMG, 1993). Various types of tethers and systems can be used for space transportation. Short electrodynamic tethers can use solar power to "push" against a planetary magnetic field to achieve propulsion without the expenditure of propellant. The planned Propulsive Small Expendable Deployer System (ProSEDS) experiment will demonstrate electrodynamic tether thrust during its flight in early 2000. Utilizing completely different physical principles, long nonconducting tethers can exchange momentum between two masses in orbit to place one body into a higher orbit or a transfer orbit for lunar and planetary missions. Recently completed system studies of this concept indicate that it would be a relatively low-cost, in-space asset with long-term, multimission capability. Tethers can also be used to support space science by providing a mechanism for precision formation flying and for reaching regions of the upper atmosphere that were previously inaccessible. (C) 1999 COSPAR. Published by Elsevier Science Ltd. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Univ Michigan, Space Phys Res Lab, Ann Arbor, MI 48109 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Johnson, L (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 10 TC 17 Z9 23 U1 0 U2 8 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 1999 VL 24 IS 8 BP 1055 EP 1063 DI 10.1016/S0273-1177(99)00553-0 PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP17V UT WOS:000084336900014 ER PT B AU Sikes, NE AF Sikes, NE BE Bromage, TG Schrenk, F TI Plio-Pleistocene floral context and habitat preferences of sympatric hominid species in East Africa SO AFRICAN BIOGEOGRAPHY, CLIMATE CHANGE & HUMAN EVOLUTION SE HUMAN EVOLUTION SERIES LA English DT Proceedings Paper CT 119th International Symposium of the Wenner-Gren Foundation CY OCT 25-NOV 04, 1995 CL SALIMA, MALAWI SP Wenner Gren Fdn C1 Smithsonian Inst, Dept Anthropol, Musseum Support Ctr, MRC 534, Washington, DC 20560 USA. NR 0 TC 17 Z9 17 U1 0 U2 1 PU OXFORD UNIV PRESS PI NEW YORK PA 198 MADISON AVENUE, NEW YORK, NY 10016 USA BN 0-19-511437-X J9 HUMAN EVOLUT SER PY 1999 BP 301 EP 315 PG 15 WC Anthropology SC Anthropology GA BQ27T UT WOS:000087779100021 ER PT S AU Ho, LC AF Ho, LC BE Schmitt, HR Kinney, AL Ho, LC TI LINERs as low-luminosity active galactic nuclei SO AGN/NORMAL GALAXY CONNECTION SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT E1 2 Symposium of COSPAR Scientific Commission E on the AGN/Normal Galaxy Connection, 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP Comm Space Res ID DWARF SEYFERT NUCLEI; ULTRAVIOLET EMISSION; FAST SHOCKS; GALAXIES; SEARCH; ACCRETION; NEARBY AB Many nearby galaxies contain optical signatures of nuclear activity in the form of LINER nuclei. LINERs may be the weakest and most common manifestation of the quasar phenomenon. The physical origin of this class of objects, however, has been ambiguous. I draw upon a number of recent observations to argue that a significant fraction of LINERs are low-luminosity active galactic nuclei. The evidence in favor of this interpretation includes the similarity in the properties of the host galaxies of LINERs and Seyferts, the detection of broad-line regions, the detection of black holes in a handful of nearby galaxies that are spectroscopically recognized as LINERs, the presence of a compact nuclear source seen in the radio, ultraviolet, and X-rays, and the detection of nonthermal spectra in the hard X-ray band. The spectral energy distributions of LINERs differ dramatically from those of luminous AGNs, most notably in the absence of the "big blue bump." This and other characteristics suggest that the central engine in LINERs is fed by a very low accretion rate. (C) 1999 COSPAR. Published by Elsevier Science Ltd. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Carnegie Observ, Pasadena, CA 91101 USA. RP Ho, LC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 44 TC 37 Z9 37 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-SERIES PY 1999 VL 23 IS 5/6 BP 813 EP 822 DI 10.1016/S0273-1177(99)00211-2 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BN23V UT WOS:000081222000001 ER PT S AU Crosas, M Wood, K Sakamoto, K Scoville, NZ Yun, MS Genzel, R Tacconi, LJ AF Crosas, M Wood, K Sakamoto, K Scoville, NZ Yun, MS Genzel, R Tacconi, LJ BE Schmitt, HR Kinney, AL Ho, LC TI Disks in the Arp220 nuclei: Modeling high resolution line and continuum observations SO AGN/NORMAL GALAXY CONNECTION SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 2 Symposium of COSPAR Scientific Commission zE on the AGN/Normal Galaxy Connection, 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP Comm Space Res ID ARP-220 AB We model molecular and near-infrared emission from the central region of the ultra-luminous infrared galaxy Arp220. We use high angular resolution CO data taken with the Owens Valley millimeter array and NIR images from HST/NICMOS to compare with Monte Carlo line radiative transfer and scattering models. The models suggest that each one of the two nuclei of Arp220 has a dusty molecular disk with a mass of about 10(9) M., which is in Keplerian rotation. (C)1999 COSPAR. Published by Elsevier Science Ltd. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Pasadena, CA 91125 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. RP Crosas, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 9 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 1999 VL 23 IS 5/6 BP 1057 EP 1060 DI 10.1016/S0273-1177(99)00247-1 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BN23V UT WOS:000081222000039 ER PT S AU Di Matteo, T Fabian, AC Carilli, CL Ivison, RJ AF Di Matteo, T Fabian, AC Carilli, CL Ivison, RJ BE Schmitt, HR Kinney, AL Ho, LC TI Testing the ADAF paradigim for supermassive black holes in elliptical galaxies SO AGN/NORMAL GALAXY CONNECTION SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E1 2 Symposium of COSPAR Scientific Commission zE on the AGN/Normal Galaxy Connection, 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP Comm Space Res ID LUMINOSITY AB The growing evidence for supermassive black holes in the centres of nearby galaxies has brought into sharper focus the question of why elliptical galaxies, rich in hot gas, do not possess quasar-like luminosities. Recent studies suggest that the presence of advection-dominated accretion flows (ADAFs) with their associated low radiative efficiency, might provide a promising explanation for the observed quiescence of these systems. Here, we present new high-frequency radio observations of the three giant, low-luminosity elliptical galaxies NGC 4649, NGC 4472 and NGC 4636 obtained using the Very Large Array (VLA) and the sub-millimetre common-user bolometer array (SCUBA) on the James Clerk Maxwell Telescope (JCMT). The new radio limits disagree severely with the canonical ADAF predictions which significantly overestimate the observed flux. If the accretion in these objects occurs in an advection-dominated mode then our radio limits imply that the emission from their central regions must be suppressed. We present the possibility that the magnetic field in the flow is extremely low or that synchrotron emission is free-free absorbed by cold material in the accretion flow. We also discuss whether slow non-radiating accretion flows may drive winds/outflows to remove energy, angular momentum and mass so that the central densities, pressures and emissivities are much smaller than in a standard ADAF (Di Matteo et al. 1998). (C)1999 COSPAR. Published by Elsevier Science Ltd. C1 Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Natl Radio Astron Observ, Socorro, NM 87801 USA. Univ Edinburgh, Astron Inst, Dept Phys & Astron, Edinburgh EH9 3HJ, Midlothian, Scotland. RP Di Matteo, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Ivison, R./G-4450-2011 OI Ivison, R./0000-0001-5118-1313 NR 9 TC 1 Z9 1 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 1999 VL 23 IS 5/6 BP 1075 EP 1078 DI 10.1016/S0273-1177(99)00267-7 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BN23V UT WOS:000081222000042 ER PT J AU Scherer, JC AF Scherer, JC TI Drawing shadows to stone: The photography of the Jesup North Pacific Expedition, 1897-1902 SO AMERICAN INDIAN CULTURE AND RESEARCH JOURNAL LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Scherer, JC (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU U C L A, AMER INDIAN STUDIES CENTER PI LOS ANGELES PA 3220 CAMPBELL HALL, BOX 951548, LOS ANGELES, CA 90095-1548 USA SN 0161-6463 J9 AM INDIAN CULT RES J JI Am. Indian Cult. Res. J. PY 1999 VL 23 IS 2 BP 166 EP 167 PG 2 WC History SC History GA 309HW UT WOS:000086763300020 ER PT J AU Fleming, PR AF Fleming, PR TI Edward S. Curtis and the North American Indian SO AMERICAN INDIAN CULTURE AND RESEARCH JOURNAL LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Fleming, PR (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU U C L A, AMER INDIAN STUDIES CENTER PI LOS ANGELES PA 3220 CAMPBELL HALL, BOX 951548, LOS ANGELES, CA 90095-1548 USA SN 0161-6463 J9 AM INDIAN CULT RES J JI Am. Indian Cult. Res. J. PY 1999 VL 23 IS 1 BP 230 EP 232 PG 3 WC History SC History GA 207GE UT WOS:000080927100029 ER PT J AU Damann, FE Miller, E Jones, EB Ubelaker, DH AF Damann, FE Miller, E Jones, EB Ubelaker, DH TI Temporal trends in morbidity in the Chesapeake Bay area: Part One. Samples, methodology, and context. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Calif State Univ Los Angeles, Los Angeles, CA 90032 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. 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 1999 SU 28 BP 114 EP 114 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 184JE UT WOS:000079607500095 ER PT J AU Koritzer, RT St Hoyme, LE AF Koritzer, RT St Hoyme, LE TI Exploring the relation between muscle insertion dimensions and tooth use. 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 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 1999 SU 28 BP 174 EP 174 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 184JE UT WOS:000079607500260 ER PT J AU Miller, E Damann, FE Ubelaker, DH Jones, EB AF Miller, E Damann, FE Ubelaker, DH Jones, EB TI Temporal trends in morbidity in the Chesapeake Bay area: Part two. Data and conclusions. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Calif State Univ Los Angeles, Los Angeles, CA 90032 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Smithsonian Inst, Natl Museum Nat Hist, 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 1999 SU 28 BP 203 EP 203 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 184JE UT WOS:000079607500343 ER PT J AU Mulhern, DM AF Mulhern, DM TI Web-based instruction in biological anthropology. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Smithsonian Inst, NMNH, 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 1999 SU 28 BP 206 EP 207 PG 2 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 184JE UT WOS:000079607500353 ER PT J AU Ortner, DJ AF Ortner, DJ TI Scurvy: its skeletal manifestations and prevalence in North and South American skeletal samples. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Smithsonian Inst, Washington, DC 20560 USA. NR 2 TC 0 Z9 0 U1 1 U2 2 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 1999 SU 28 BP 216 EP 216 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 184JE UT WOS:000079607500379 ER PT J AU Potts, R AF Potts, R TI Environments of natural selection in early Pleistocene Homo. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Smithsonian Inst, NMNH, Human Origins Program, 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 1999 SU 28 BP 224 EP 224 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 184JE UT WOS:000079607500403 ER PT J AU Ross, AH Jantz, RL Owsley, DW Cihlarz, Z Vedo, T Slaus, M Strinovic, D AF Ross, AH Jantz, RL Owsley, DW Cihlarz, Z Vedo, T Slaus, M Strinovic, D TI Allometric relationships of Americans, Croatians, and Bosnians. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Univ Tennessee, Dept Anthropol, Knoxville, TN 37996 USA. Smithsonian Inst, Dept Anthropol, Washington, DC 20560 USA. Klin Ctr, Sudsku Med, Tuzla, Bosnia & Herceg. Univ Zagreb, Zagreb 41000, Croatia. NR 0 TC 0 Z9 0 U1 2 U2 2 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 1999 SU 28 BP 236 EP 236 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 184JE UT WOS:000079607500435 ER PT J AU Ruiz-Miranda, CR Kleiman, DG Dietz, JM Moraes, E Grativol, AD Baker, AJ Beck, BB AF Ruiz-Miranda, CR Kleiman, DG Dietz, JM Moraes, E Grativol, AD Baker, AJ Beck, BB TI Food transfers in wild and reintroduced golden lion tamarins, Leontopithecus rosalia SO AMERICAN JOURNAL OF PRIMATOLOGY LA English DT Article DE callitrichids; parental care; ontogeny; foraging; communication; conspicuous signal ID COTTON-TOP TAMARINS; SAGUINUS-OEDIPUS; INFANT CARE; LITTER SIZE; PRIMATES; REPRODUCTION; MOTIVATION; CAPUCHINS; BEHAVIOR; MONKEYS AB We collected data from wild and reintroduced golden lion tamarins (Leontopithecus rosalia) to describe the behavior of donor and recipient during food transfers, evaluate the effect of supplemental feeding on food transfer behavior, and examine various hypotheses concerning the function of food transfers in primates. Behavioral observations were conducted on 12 groups of tamarins with young (N = 30) between the ages of 1 week and 1 year old. Results show that food transfers involve various behaviors, from steals by recipients to offers by donors; transfers mostly derive from adults and are directed at immature weaned young (between 3 and 9 months old); and that most items transferred were prey or fruits that require skill. to process. Eleven percent of food transfers were preceded by an adult vocalization specific to that context, whereas 86% were preceded by conspicuous infant vocalizations and begging behavior. The most common vocalizations were loud and atonal (rasps) and broad banded frequency modulated (trills). Infants born to reintroduced parents vocalized less, whereas reintroduced adults vocalized more before transferring food than their wild counterparts. Reintroduced adults and young received more food transfers (4.4 per hr) than did wild-born adults and young (2.2 per hr). Our findings suggest that food transfer in golden lion tamarins is best understood as provisioning of young that have not fully developed foraging skills to ensure they get the necessary resources for growth and survival. Am. J. Primatol. 48:305-320, 1999. (C) 1999 Wiley-Liss, Inc. C1 Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. Smithsonian Inst, Natl Zool Pk, Dept Mammals, Washington, DC 20008 USA. Univ Fed Rural Rio de Janeiro, Dept Engn Florestal, Rio De Janeiro, Brazil. Univ Maryland, Dept Zool, College Pk, MD 20742 USA. Philadelphia Zoo, Dept Mammals, Philadelphia, PA USA. RP Ruiz-Miranda, CR (reprint author), Univ Estadual Norte Fluminense, Ctr Biociencias & Biotecnol, Lab Ciencias Ambientais, BR-28015620 Rio De Janeiro, Brazil. RI Ruiz-Miranda, Carlos/A-4719-2008; Ruiz-Miranda, Carlos/H-7308-2015; Ruiz, Carlos/I-4446-2016 OI Ruiz-Miranda, Carlos/0000-0001-9786-5315; Ruiz-Miranda, Carlos/0000-0001-7360-0304; NR 54 TC 41 Z9 43 U1 1 U2 13 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0275-2565 J9 AM J PRIMATOL JI Am. J. Primatol. PY 1999 VL 48 IS 4 BP 305 EP 320 DI 10.1002/(SICI)1098-2345(1999)48:4<305::AID-AJP6>3.0.CO;2-V PG 16 WC Zoology SC Zoology GA 207GG UT WOS:000080927300006 PM 10402039 ER PT J AU Power, ML Tardif, SD Layne, DG Schulkin, J AF Power, ML Tardif, SD Layne, DG Schulkin, J TI Ingestion of calcium solutions by common marmosets (Callithrix jacchus) SO AMERICAN JOURNAL OF PRIMATOLOGY LA English DT Article DE primates; callitrichidae; ingestion; vitamin D ID SAGUINUS-OEDIPUS; LACTATION; FEMALE; RATS AB Callithrix jacchus, the common marmoset, is a small New World primate that feeds on insects, fruit, and gum, and has a high reproductive rate for a primate, Insects are generally a poor source of dietary calcium, while gums may contain significant levels of calcium. Their high reproductive rate also suggests that reproductive female C. jacchus might be susceptible to calcium deficiency. Thus, we hypothesized that common marmosets might find solutions containing calcium to be palatable. We used choice experiments to examine this phenomenon in 14 male and 19 female common marmosets, Animals were presented with identical water bottles containing either deionized water or a calcium lactate solution (either 2% or 4% calcium lactate by weight) and intake was measured. Serum 25-OH-vitamin D was monitored in a subset of the animals in the experiment to examine the role of vitamin D in this behavior. Our results demonstrated that C. jacchus can distinguish between plain water and a calcium lactate solution, and that in general they prefer calcium solutions. Although animals with marginal vitamin D status did have strong preferences for calcium solutions, they did not ingest significantly more of the calcium solutions than animals that were vitamin D-replete. Nulliparous females and males did not differ in the amounts of calcium solutions ingested. Lactating females ingested the greatest volume of the calcium solutions, Am. J. Primatol. 47:255-261, 1999. (C) 1999 Wiley-Liss, Inc. C1 Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Nutr Lab, Washington, DC 20008 USA. Kent State Univ, Dept Biol Sci, Kent, OH 44242 USA. Georgetown Univ, Dept Physiol & Biophys, Washington, DC USA. RP Power, ML (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Nutr Lab, Washington, DC 20008 USA. FU NCRR NIH HHS [RR02022] NR 20 TC 11 Z9 11 U1 0 U2 8 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0275-2565 J9 AM J PRIMATOL JI Am. J. Primatol. PY 1999 VL 47 IS 3 BP 255 EP 261 DI 10.1002/(SICI)1098-2345(1999)47:3<255::AID-AJP7>3.0.CO;2-W PG 7 WC Zoology SC Zoology GA 172CA UT WOS:000078903700007 PM 10075439 ER PT J AU Eble, GJ AF Eble, GJ TI Morphospace and disparity approaches to development and evolution. SO AMERICAN ZOOLOGIST LA English DT Meeting Abstract C1 Smithsonian Inst, Washington, DC 20560 USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU SOC INTEGRATIVE COMPARATIVE BIOLOGY PI MCLEAN PA 1313 DOLLEY MADISON BLVD, NO 402, MCLEAN, VA 22101 USA SN 0003-1569 J9 AM ZOOL JI Am. Zool. PY 1999 VL 39 IS 5 SI SI MA 77 BP 14A EP 14A PG 1 WC Zoology SC Zoology GA 292NE UT WOS:000085800400078 ER PT J AU McCall, L Eble, GJ AF McCall, L Eble, GJ TI Diversity of natural kinds in biology. SO AMERICAN ZOOLOGIST LA English DT Meeting Abstract C1 Smithsonian Inst, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU SOC INTEGRATIVE COMPARATIVE BIOLOGY PI MCLEAN PA 1313 DOLLEY MADISON BLVD, NO 402, MCLEAN, VA 22101 USA SN 0003-1569 J9 AM ZOOL JI Am. Zool. PY 1999 VL 39 IS 5 SI SI MA 315 BP 53A EP 53A PG 1 WC Zoology SC Zoology GA 292NE UT WOS:000085800400316 ER PT J AU Savitzky, AH Roberts, KA Rand, AS AF Savitzky, AH Roberts, KA Rand, AS TI Organization of elastic fibers in the vocal sac of frogs. SO AMERICAN ZOOLOGIST LA English DT Meeting Abstract C1 Old Dominion Univ, Norfolk, VA USA. Smithsonian Trop Res Inst, Washington, DC USA. NR 0 TC 3 Z9 3 U1 0 U2 1 PU SOC INTEGRATIVE COMPARATIVE BIOLOGY PI MCLEAN PA 1313 DOLLEY MADISON BLVD, NO 402, MCLEAN, VA 22101 USA SN 0003-1569 J9 AM ZOOL JI Am. Zool. PY 1999 VL 39 IS 5 SI SI MA 579 BP 98A EP 98A PG 1 WC Zoology SC Zoology GA 292NE UT WOS:000085800400581 ER PT B AU Schlegel, EM AF Schlegel, EM BE Hellier, C Mukai, K TI RXTE observations of the IPs PQ gem and AO Psc SO ANNAPOLIS WORKSHOP ON MAGNETIC CATACLYSMIC VARIABLES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Annapolis Workshop on Magnetic Cataclysmic Variables CY JUL 13-17, 1998 CL ANNAPOLIS, MD ID GINGA AB The Rossi X-ray Timing Explorer (RSTE) contains proportional counters with the largest effective area ever orbited (similar to 7000 cm(2)). RSTE also has the capability of handling a very high telemetry rate so that every photon can be sent to the ground for subsequent analysis. Finally, the combination of the proportional counters and the phoswich detectors of the second instrument (HEXTE) together cover the 2 to similar to 50 keV band. This bandpass potentially allows us to measure the temperature of the hard spectral component that comes from the accretion impact at the magnetic pole. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Schlegel, EM (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NR 3 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 1-886733-77-5 J9 ASTR SOC P PY 1999 VL 157 BP 60 EP 62 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BM90T UT WOS:000080088400009 ER PT B AU Grindlay, JE AF Grindlay, JE BE Hellier, C Mukai, K TI Magnetic CVs in globular clusters SO ANNAPOLIS WORKSHOP ON MAGNETIC CATACLYSMIC VARIABLES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Annapolis Workshop on Magnetic Cataclysmic Variables CY JUL 13-17, 1998 CL ANNAPOLIS, MD ID HUBBLE-SPACE-TELESCOPE; X-RAY-EMISSION; ALL-SKY SURVEY; CATACLYSMIC VARIABLES; CENTAURUS X-4; ACCRETION DISKS; BINARIES; CORE; IDENTIFICATION; DISCOVERY AB Cataclysmic variables (CVs) are tracers of dynamical evolution in globular clusters. A significant sample has been found by the relatively shallow H alpha surveys conducted with HST thus far in just three globulars: NGC 6397 (3 objects), NGC 6752 (2), and omega Cen (2). These are identified with the low-luminosity X-ray sources discovered in these globulars with similarly moderate-depth ROSAT surveys. Follow-up spectroscopy of the initial 3 CV candidates in NGC 6397 with the FOS on HST suggests they may be magnetic CVs of the intermediate polar (IP) type, and follow-up deep imaging with both HST and ROSAT yield a 4(th) confirmed and 5(th) strong candidate CV near the center of this collapsed-core cluster. The optical versus X-ray properties of the 4 confirmed IP candidates in NGC 6397 are compared with disk IPs, and arguments for and against this interpretation are presented. The possible strong excess of magnetic. CVs in globulars will be tested with much deeper HST/AXAF surveys. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Grindlay, JE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 38 TC 26 Z9 26 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-77-5 J9 ASTR SOC P PY 1999 VL 157 BP 377 EP 387 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BM90T UT WOS:000080088400055 ER PT J AU Cameron, AGW AF Cameron, AGW TI Adventures in cosmogony SO ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS LA English DT Article DE autobiography; nucleosynthesis; stellar astrophysics; planetary sciences; scientific advising ID PRIMITIVE SOLAR NEBULA; EVOLUTION; MODELS; SYSTEM; STARS AB I was born and educated in Canada, obtaining my PhD in experimental nuclear physics. When I learned that technetium had been found in stellar spectra, I taught myself some astrophysics and began to study stellar nucleosynthesis. This is an account of those studies and of the pathway through much of theoretical astrophysics and planetary physics that was a natural outgrowth of the pursuit of nucleosynthesis problems. I also discuss my experiences in government service and in academia, in organization of conferences, in governmental advising, and in academic administration. In particular, I emphasize the logical connections among the various scientific themes that I have pursued. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cameron, AGW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 64 TC 14 Z9 14 U1 0 U2 1 PU ANNUAL REVIEWS INC 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 1999 VL 37 BP 1 EP 36 DI 10.1146/annurev.astro.37.1.1 PG 36 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 258WL UT WOS:000083862600002 ER PT J AU Nieser, N Polhemus, DA AF Nieser, N Polhemus, DA TI Four new species of Rhagovelia (Heteroptera : Veliidae) from Minas Gerais (Brazil), with a key to the regional species of the angustipes complex SO AQUATIC INSECTS LA English DT Article DE Veliidae; Rhagovelia; Brazil; Minas Gerais; key AB Four new species of Rhagovelia, R. ochroischion, R. turmalis, R. sbolos, and R. trianguloides, are described from Mines Gerais, Brazil, along with the previously unknown female of R. triangula Drake. A key to the Rhagovelia species of the angustipes complex known from Minas Gerais and adjacent areas is provided. C1 Smithsonian Inst, Washington, DC 20560 USA. RP Nieser, N (reprint author), Htg Eduardstr 16, NL-4001 RG Tiel, Netherlands. NR 6 TC 14 Z9 18 U1 0 U2 0 PU SWETS ZEITLINGER PUBLISHERS PI LISSE PA P O BOX 825, 2160 SZ LISSE, NETHERLANDS SN 0165-0424 J9 AQUAT INSECT JI Aquat. Insects PD JAN PY 1999 VL 21 IS 1 BP 53 EP 76 DI 10.1076/aqin.21.1.53.4540 PG 24 WC Entomology SC Entomology GA 179EQ UT WOS:000079313000006 ER PT J AU Dehejia, V AF Dehejia, V TI The Dvaravati wheels of the law and the indianization of South East Asia SO ARTIBUS ASIAE LA English DT Book Review C1 Smithsonian Inst, Arthur M Sackler Gallery, Freer Gallery Art, Washington, DC 20560 USA. RP Dehejia, V (reprint author), Smithsonian Inst, Arthur M Sackler Gallery, Freer Gallery Art, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU ARTIBUS ASIAE PI ZURICH PA MUSEUM RIETBERG GABLERSTRASSE 15, CH-8002 ZURICH, SWITZERLAND SN 0004-3648 J9 ARTIBUS ASIAE JI Artibus Asiae PY 1999 VL 59 IS 1-2 BP 140 EP 142 DI 10.2307/3249865 PG 3 WC Art; Asian Studies SC Art; Asian Studies GA 270WC UT WOS:000084559300005 ER PT B AU Brickhouse, NS AF Brickhouse, NS BE Mehringer, DM Plante, RL Roberts, DA TI Systemization and use of atomic data for astrophysical modeling SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS VIII SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 8th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 98) CY NOV 01-04, 1998 CL UNIV ILLINOIS URBANA-CHAMPAIGN, URBANA, IL SP Natl Ctr Supercomp Applicat, Univ Illinois Astron Dept, Smithsonian Astrophys Observ, Natl Radio Astron Observ, Natl Opt Astron Observ, Space Telescope European Coodinating Facility, Sun Microsyst, Res Syst Inc, NASA, Natl Sci Fdn HO UNIV ILLINOIS URBANA-CHAMPAIGN ID RAY AB The growth of supercomputing capabilities over the past decade has led to tremendous opportunities to produce theoretical atomic data for use in modeling astrophysical plasmas; however, not all data are created equally. Both accurate and complete atomic data are important to astrophysical modeling via plasma codes. Critical theoretical evaluations, experimental benchmarks, and even astrophysical observations themselves are all useful in assessing the temperatures, densities, opacities, abundances, and other physical quantities determined from spectroscopy. The database challenge for the future is to move toward increasing both flexibility and standardization of atomic data formats so that the quality of the data can be taken into account in modeling. Problems in X-ray spectroscopy will illustrate the importance of opening up what has often been a black box to many astronomers. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Brickhouse, NS (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NR 8 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 1-886733-94-5 J9 ASTR SOC P PY 1999 VL 172 BP 25 EP 32 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN88T UT WOS:000083347000006 ER PT B AU Garnavich, P AF Garnavich, P BE Mehringer, DM Plante, RL Roberts, DA TI Cosmology from high redshift supernovae SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS VIII SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 8th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 98) CY NOV 01-04, 1998 CL UNIV ILLINOIS URBANA-CHAMPAIGN, URBANA, IL SP Natl Ctr Supercomp Applicat, Univ Illinois Astron Dept, Smithsonian Astrophys Observ, Natl Radio Astron Observ, Natl Opt Astron Observ, Space Telescope European Coodinating Facility, Sun Microsyst, Res Syst Inc, NASA, Natl Sci Fdn HO UNIV ILLINOIS URBANA-CHAMPAIGN AB The discovery of a correlation between the light curve shape and intrinsic brightness has made Type Ia supernovae exceptionally accurate distance indicators out to cosmologically interesting redshifts. Ground-based searches and follow-up as well as Hubble Space Telescope observations of Type Ia supernovae have produced a significant number of objects with redshifts between 0.3 and 1.0. The distant SNe, when combined with a local sample analyzed in the same way, provide reliable constraints on the deceleration and age of the Universe. Early this year, an analysis of a handful of Type Ia events indicated that the deceleration was too small for gravitating matter alone to make a flat Universe. A larger sample of supernovae gives the surprising result that the Universe is accelerating, implying the existence of a cosmological constant or some other exotic form of energy. The success of this research has depended on the development of algorithms and software to register, scale and subtract CCD images taken weeks apart and to search for variable objects. A good fraction of the point-sources identified are asteroids, variable stars, or AGN, so spec tra are needed to confirm the identification as a Type Ia supernova and obtain a redshift. The best candidates are followed photometrically to construct light curves. The steps to transform the observed light curves into cosmologically interesting results will also be described. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Garnavich, P (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NR 6 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 1-886733-94-5 J9 ASTR SOC P PY 1999 VL 172 BP 33 EP 37 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN88T UT WOS:000083347000007 ER PT B AU Kleiner, S AF Kleiner, S BE Mehringer, DM Plante, RL Roberts, DA TI Small, fast and reusable: A satellite planning and scheduling system SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS VIII SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 8th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 98) CY NOV 01-04, 1998 CL UNIV ILLINOIS URBANA-CHAMPAIGN, URBANA, IL SP Natl Ctr Supercomp Applicat, Univ Illinois Astron Dept, Smithsonian Astrophys Observ, Natl Radio Astron Observ, Natl Opt Astron Observ, Space Telescope European Coodinating Facility, Sun Microsyst, Res Syst Inc, NASA, Natl Sci Fdn HO UNIV ILLINOIS URBANA-CHAMPAIGN AB The SWAS planning and scheduling system provides all functions from ephemeris processing to guide star selection to timeline generation. It embodies a dynamic scheduling algorithm which allows schedules to be rebuilt or slipped while conserving the scheduling effort already invested. A novel graphical interface provides interactive scheduling. The system uses a component design for efficient reuse. The software is available(1) for use by other missions. C1 Smithsonian Astrophys Observ, Cambridge, MA 02176 USA. RP Kleiner, S (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02176 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 1-886733-94-5 J9 ASTR SOC P PY 1999 VL 172 BP 77 EP 80 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN88T UT WOS:000083347000016 ER PT B AU Accomazzi, A Eichhorn, G Kurtz, MJ Grant, CS Murray, SS AF Accomazzi, A Eichhorn, G Kurtz, MJ Grant, CS Murray, SS BE Mehringer, DM Plante, RL Roberts, DA TI The ADS bibliographic reference resolver SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS VIII SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 8th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 98) CY NOV 01-04, 1998 CL UNIV ILLINOIS URBANA-CHAMPAIGN, URBANA, IL SP Natl Ctr Supercomp Applicat, Univ Illinois Astron Dept, Smithsonian Astrophys Observ, Natl Radio Astron Observ, Natl Opt Astron Observ, Space Telescope European Coodinating Facility, Sun Microsyst, Res Syst Inc, NASA, Natl Sci Fdn HO UNIV ILLINOIS URBANA-CHAMPAIGN AB An increasingly larger number of publishers and institutions are using the NASA Astrophysics Data System (ADS) to verify the existence and availability of references published in the astronomical literature. In this paper we discuss the tools and utilities that the ADS is developing to provide the capability to automatically parse, identify, and verify the existence and correctness of citations appearing in astronomical publications. Details of the implementation are presented and some preliminary results from the use of the resolver are shown. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Accomazzi, A (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. RI Eichhorn, Guenther/C-9480-2009 OI Eichhorn, Guenther/0000-0002-3032-1978 NR 1 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 1-886733-94-5 J9 ASTR SOC P PY 1999 VL 172 BP 291 EP 294 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN88T UT WOS:000083347000067 ER PT B AU Grumm, D AF Grumm, D BE Mehringer, DM Plante, RL Roberts, DA TI Optimizing functions using ASCFIT SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS VIII SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 8th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 98) CY NOV 01-04, 1998 CL UNIV ILLINOIS URBANA-CHAMPAIGN, URBANA, IL SP Natl Ctr Supercomp Applicat, Univ Illinois Astron Dept, Smithsonian Astrophys Observ, Natl Radio Astron Observ, Natl Opt Astron Observ, Space Telescope European Coodinating Facility, Sun Microsyst, Res Syst Inc, NASA, Natl Sci Fdn HO UNIV ILLINOIS URBANA-CHAMPAIGN AB As part of the Smithsonian Astrophysical Observatory AXAF Science Center (ASC) Data Analysis Environment, ASCFIT was designed as a generalized fitting engine to enable users to fit models to the data that will be returned by AXAF, the Advanced X-ray Astrophysical Facility (Doe et al. 1996). I present a description of the use of a development version of ASCFIT as a function optimizer, in which the optimization methods available within ASCFIT are applied to seven benchmark functions of varying complexity. These functions are the 2-dimensional Gaussian function previously investigated by ASC, and six functions commonly used in optimization testing. The optimization methods combining the Powell technique with one of several other techniques successfully converged for all but one of the benchmark functions. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Grumm, D (reprint author), Smithsonian Astrophys Observ, 60 Garden St,MS 81, Cambridge, MA 02138 USA. NR 4 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 1-886733-94-5 J9 ASTR SOC P PY 1999 VL 172 BP 365 EP 368 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN88T UT WOS:000083347000080 ER PT B AU Joye, W Mandel, E AF Joye, W Mandel, E BE Mehringer, DM Plante, RL Roberts, DA TI SAOTk: Tcl/Tk widgets for imaging and data visualization SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS VIII SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 8th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 98) CY NOV 01-04, 1998 CL UNIV ILLINOIS URBANA-CHAMPAIGN, URBANA, IL SP Natl Ctr Supercomp Applicat, Univ Illinois Astron Dept, Smithsonian Astrophys Observ, Natl Radio Astron Observ, Natl Opt Astron Observ, Space Telescope European Coodinating Facility, Sun Microsyst, Res Syst Inc, NASA, Natl Sci Fdn HO UNIV ILLINOIS URBANA-CHAMPAIGN AB SAOTk is an integrated set of Tcl/Tk widgets for astronomical imaging and data visualization. The widget set is composed of an Image, Panner, Magnifier, and Colorbar widget. In addition to ''classical" support for imaging FITS data, manipulating colormaps, region marking, and coordinate readout (including WCS), SAOTk widgets also support arbitrary image scaling and rotation, advanced printing and graphics, image mosaics, and shared memory. The SAOTk widgets will be incorporated into the next major release of SAOtng, a release that will allow the astronomical community to begin moving away from its primary dependence on Unix and X11. They also can be incorporated into ally 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 3 Z9 3 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-94-5 J9 ASTR SOC P PY 1999 VL 172 BP 429 EP 432 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN88T UT WOS:000083347000095 ER PT B AU Mink, DJ AF Mink, DJ BE Mehringer, DM Plante, RL Roberts, DA TI WCSTools: An image astrometry toolkit SO ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS VIII SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 8th Annual Conference for Astronomical Data Analysis Software and Systems (ADASS 98) CY NOV 01-04, 1998 CL UNIV ILLINOIS URBANA-CHAMPAIGN, URBANA, IL SP Natl Ctr Supercomp Applicat, Univ Illinois Astron Dept, Smithsonian Astrophys Observ, Natl Radio Astron Observ, Natl Opt Astron Observ, Space Telescope European Coodinating Facility, Sun Microsyst, Res Syst Inc, NASA, Natl Sci Fdn HO UNIV ILLINOIS URBANA-CHAMPAIGN AB Very few people want to deal with the details of positional astronomy, but many astronomers want to know precise positions of objects in the sky. New instruments, such as fiber-fed spectrographs, require more precise positions than are available for many objects. WCSTools provides programs and subroutines which allow both scientists and programmers to access astrometric information using the world coordinate system (WCS) of an image. WCSTools programs translate between image and sky coordinates, list catalog stars in the area covered by an image, find stars in an image and list them with their sky positions, and fit a WCS by matching image objects to catalogs. SAOimage, SkyCat, and SAOtng use WCSTools subroutines to display sky coordinates while browsing an image. The software reads and writes FITS and IRAF .imh images and deals easily with Space Telescope and Digitized Sky Survey FITS images. The proposed FITS WCS standard is being tracked, and interim formats are being supported. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Mink, DJ (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NR 8 TC 26 Z9 26 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-94-5 J9 ASTR SOC P PY 1999 VL 172 BP 498 EP 501 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN88T UT WOS:000083347000112 ER PT J AU Owen, G AF Owen, G TI Benjamin Apthorp Gould and the founding of the Astronomical Journal SO ASTRONOMICAL JOURNAL LA English DT Biographical-Item AB On the sesquicentennial of the Astronomical Journal, we commemorate the life of its founder, Benjamin Apthorp Gould (1824-1896), and examine the precarious and heroic early days of this pioneering serial. The first six volumes appeared between 1849 November 2 and 1861 February, and after a hiatus of 25 years, Gould resumed the publication on 1886 November 2. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Owen, G (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 12 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 JAN PY 1999 VL 117 IS 1 BP 1 EP 5 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158GU UT WOS:000078108300002 ER PT J AU Rothenberg, M AF Rothenberg, M TI Observers, publications, and surveys: Astronomy in the United States in 1849 SO ASTRONOMICAL JOURNAL LA English DT Article AB By the mid-19th century, astronomy in the United States was productive and growing, Information gathered by and at the behest of the Smithsonian Institution shows that the community consisted of approximately 50 individuals, including a significant number of military officers, and a dozen observatories. Americans were deeply involved in astronomical research, and the discipline was entrenched in the college curriculum. What the discipline lacked was an adequate publication vehicle to ensure refereed, rapid dissemination of observations. C1 Smithsonian Inst, Smithsonian Inst Arch, Joseph Henry Papers Project, Washington, DC 20560 USA. RP Rothenberg, M (reprint author), Smithsonian Inst, Smithsonian Inst Arch, Joseph Henry Papers Project, 2188 Arts & Ind, Washington, DC 20560 USA. NR 13 TC 2 Z9 2 U1 2 U2 2 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 1999 VL 117 IS 1 BP 6 EP 8 DI 10.1086/300713 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158GU UT WOS:000078108300003 ER PT J AU Caldwell, N Rose, JA Dendy, K AF Caldwell, N Rose, JA Dendy, K TI On the origins of starburst and poststarburst galaxies in nearby clusters SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : clusters : general; galaxies : clusters : individual (Coma, DC 2048-52); galaxies : evolution; galaxies : interactions; galaxies : starburst ID SPACE-TELESCOPE OBSERVATIONS; BUTCHER-OEMLER CLUSTERS; MERGER REMNANT NGC-7252; COMA CLUSTER; STAR-FORMATION; DISTANT CLUSTERS; RICH CLUSTERS; REDSHIFT CLUSTERS; SPECTROSCOPY; PHOTOMETRY AB Nubble Space Telescope (NST) Wide Field Planetary Camera 2 images in B (F450W) and I (F814W) have been obtained for three starburst (SB) and two poststarburst (PSB) galaxies in the Coma Cluster and for three such galaxies in the cluster DC 048-52. V (F555W) and I images for an additional PSB galaxy in Coma have been extracted from the HST archive. Six of these galaxies were previously classified as E/S0 on the basis of ground-based images, two as Sa, and the other as an irregular. The HST images reveal these SB/PSB galaxies to be heterogeneous in morphology. Nevertheless, a common theme is that many of them, especially the SE galaxies, tend to have centralized spiral structure that appears simply as a bright "bulge" on ground-based images. In addition, while some PSB galaxies exhibit distinct spiral structure, on the whole they have smoother morphologies than the SE galaxies. The morphologies and luminosity profiles are generally consistent with substantial starbursts, in the form of centralized spiral structure (the SE galaxies), that fade into smoother morphologies (the PSB galaxies), with lingering spectroscopic evidence for past central starbursts. An important point is that the PSB galaxies retain disks; i.e., they have not evolved into spheroidal systems. While the morphologies revealed in the HST images are heterogeneous, and thus may not fit well into a single picture, we see evidence in several cases that the morphologies and centralized star formation have been driven by external tidal perturbations. We discuss several physical mechanisms for inducing star formation in cluster galaxies with a view toward explaining the particular morphologies seen in the HST images. C1 Smithsonian Inst, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. RP Caldwell, N (reprint author), Smithsonian Inst, Fred Lawrence Whipple Observ, Box 97,670 Mt Hopkins Rd, Amado, AZ 85645 USA. EM caldwell@flwo99.sao.arizona.edu; jim@physics.unc.edu; dendy@physics.unc.edu NR 90 TC 35 Z9 36 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 JAN PY 1999 VL 117 IS 1 BP 140 EP 156 DI 10.1086/300679 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158GU UT WOS:000078108300015 ER PT J AU Bally, J Reipurth, B Lada, CJ Billawala, Y AF Bally, J Reipurth, B Lada, CJ Billawala, Y TI Multiple CO outflows in Circinus: The churning of a molecular cloud SO ASTRONOMICAL JOURNAL LA English DT Article DE stars : formation; stars : pre-main-sequence ID HERBIG-HARO FLOWS; YOUNG STARS; KINEMATICS; OBJECTS AB We present a millimeter-wave study of a cluster of bipolar CO outflows embedded in the western end of the Circinus molecular cloud complex, G317-4, that is traced by very high optical extinction. For an assumed distance of 700 pc, the entire Circinus cloud is estimated to have a mass of about 5 x 10(4) M.. The opaque western portion that was mapped in this study has a mass of about 10(3) M., contains a number of embedded infrared sources and various compact 1.3 mm continuum sources, and has a remarkable filamentary structure with numerous cavities that appears to be the fossil remnants of past star formation activity. The most active star-forming region in this part of Circinus is centered around a compact cluster of millimeter continuum sources associated with IRAS 14564-6254 and IRAS 14563-6301, which lies about 7' to the south. This region contains two known Herbig-Haro objects, HH 76 and HH 77, and a profusion of overlapping high-velocity CO outflow lobes. Among these, we can clearly distinguish the two largest outflows in Circinus (flows A and B), which appear to originate from the two brightest IRAS sources. This region also contains at least two other prominent but overlapping bipolar CO outflows (flows C and C'), one of which may be associated with IRAS 14564-6258. Two compact and relatively low-velocity CO outflows lie at the northern periphery of the Circinus core and are associated with IRAS 14563-6250 (flow E), a source also detected as a 1.3 mm continuum source, and with IRAS 14562-6248 (flow G). A small but prominent reflection nebula associated with the nebulous star vBH 65a and a coaxial Herbig-Haro jet, HH 139, is located at the southeastern edge of this cloud core and illuminates part of a cavity seen as a low-extinction region. A faint and low-mass CO molecular flow is associated with vBH 65a and HH 139 (flow F). The infrared source IRAS 14580-6303 drives a small CO flow (flow I). A second, active center of star formation is centered on the source IRAS 14592-6311, on the peculiar Herbig Ae/Be star vBH 65b, about 20' to the southeast of the main cloud core; four HH objects, HH 140 through HH 143, and a compact CO outflow are located here (flow D). About 5' farther south, IRAS 14596-6320 drives yet another outflow (now H). Thus, the mapped portion of Circinus contains at least 10 CO-emitting molecular outflows. Assuming that star formation has continued at a steady rate for the last several hundred thousand years, the Circinus cloud is expected to have produced dozens of young stars. Their outflows have severely altered the structure and kinematics of this cloud, as evidenced by the multitude of prominent cavities and dust filaments that outline their boundaries. This level of star formation activity is consistent with the numerous post-outflow phase Ha emission-line stars that have been found in this region. The Circinus cloud complex is an archetypical case where star formation activity may have profoundly affected the structure of a molecular cloud, producing its strikingly filamentary and cavitated appearance and providing further evidence that star formation may be a self-regulated process. C1 Univ Colorado, Ctr Astrophys & Space Astron, Dept Astrophys & Planetary Sci, Boulder, CO 80309 USA. Univ Colorado, Ctr Astrobiol, Boulder, CO 80309 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Bally, J (reprint author), Univ Colorado, Ctr Astrophys & Space Astron, Dept Astrophys & Planetary Sci, Campus Box 389, Boulder, CO 80309 USA. NR 22 TC 49 Z9 49 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 JAN PY 1999 VL 117 IS 1 BP 410 EP 428 DI 10.1086/300672 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158GU UT WOS:000078108300036 ER PT J AU Torres, G Henry, TJ Franz, OG Wasserman, LH AF Torres, G Henry, TJ Franz, OG Wasserman, LH TI The nearby low-mass visual binary Wolf 424 SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : visual; stars : fundamental parameters; stars : individual (Wolf 424); stars : low-mass, brown dwarfs ID PROPER-MOTION STARS; LONG-TERM VARIABILITY; PHOTOGRAPHIC ASTROMETRY; SUBSTELLAR MASSES; FLARE STARS; DWARF-M; PHOTOMETRY; EVOLUTIONARY; MODELS AB We present new measurements of the relative positions of the components of the low-mass visual binary Wolf 424 (M5.5 Ve) made with the Fine Guidance Sensors on the Hubble Space Telescope. Previous analyses of the astrometric orbit of this system indicated that the components have substellar masses (Heintz; Schultz et al.), raising considerable interest as the first candidate brown dwarfs to have their masses measured dynamically. These studies relied partly on visual and photographic measurements, which are affected by systematic errors in the angular separation and have thus biased those solutions. Our new orbital solution using only the position angles of the early measurements together with all available modern high-resolution observations including our own shows that the component masses are clearly above the substellar limit (M-A = 0.143 +/- 0.011 M., M-B = 0.131 +/- 0.010 M.), and thus they are not brown dwarfs. Recent evolutionary models for low-mass stars show good agreement with the location of Wolf 424A and B in the mass-luminosity diagram in the K band. In addition, we show that while the secondary appears to have normal colors compared to similar M dwarfs, the primary star is fainter than expected at optical wavelengths (B, V), possibly owing to significant spot coverage. This is consistent with the strong flaring activity displayed by the system. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Lowell Observ, Flagstaff, AZ 86001 USA. RP Torres, G (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 59 TC 23 Z9 24 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 JAN PY 1999 VL 117 IS 1 BP 562 EP 573 DI 10.1086/300708 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158GU UT WOS:000078108300050 ER PT J AU Holman, MJ Wiegert, PA AF Holman, MJ Wiegert, PA TI Long-term stability of planets in binary systems SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : general; celestial mechanics, stellar dynamics; planetary systems ID ELLIPTIC RESTRICTED PROBLEM; 3-BODY SYSTEMS; DOUBLE STARS; ORBITS; 16-CYGNI-B AB A simple question of celestial mechanics is investigated: in what regions of phase space near a binary system can planets persist for long times? The planets are taken to be test particles moving in the field of an eccentric binary system. A range of values of the binary eccentricity and mass ratio is studied, and both the case of planets orbiting close to one of the stars, and that of planets outside the binary orbiting the system's center of mass, are examined. From the results, empirical expressions are developed for both (1) the largest orbit around each of the stars and (2) the smallest orbit around the binary system as a whole, in which test particles survive the length of the integration (10(4) binary periods). The empirical expressions developed, which are roughly linear in both the mass ratio mu and the binary eccentricity e, are determined for the range 0.0 less than or equal to e less than or equal to 0.7-0.8 and 0.1 less than or equal to mu less than or equal to 0.9 in both regions and can be used to guide searches for planets in binary systems. After considering the case of a single low-mass planet in binary systems, the stability of a mutually interacting system of planets orbiting one star of a binary system is examined, though in less detail. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. York Univ, Dept Phys & Astron, Toronto, ON M3J 3P1, Canada. RP Holman, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 23 TC 441 Z9 442 U1 1 U2 3 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 1999 VL 117 IS 1 BP 621 EP 628 DI 10.1086/300695 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158GU UT WOS:000078108300054 ER PT J AU Markevitch, M AF Markevitch, M TI Cluster gas temperature maps with ASCA and beyond SO ASTRONOMISCHE NACHRICHTEN LA English DT Article DE clusters of galaxies : X-ray intergalactic medium ID X-RAY; GALAXIES; ABUNDANCE; EVOLUTION AB During the past several years, ASCA has nearly completed mapping of gas temperatures in bright nearby clusters of galaxies. In several clusters, it discovered strong and irregular spatial temperature variations indicative of ongoing violent subcluster mergers. In other systems, the temperature distribution appears symmetric, indicating a relaxed state which is a necessary condition for reliable hydrostatic total mass measurements. I present a (very incomplete) review of these results, discuss their implications for understanding of physical processes in the intracluster gas and for the cluster mass measurements. I also mention some interesting studies that will become possible with the forthcoming Chandra X-ray; observatory. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Markevitch, M (reprint author), 60 Garden St, Cambridge, MA 02138 USA. NR 26 TC 0 Z9 0 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0004-6337 J9 ASTRON NACHR JI Astro. Nachr. PY 1999 VL 320 IS 4-5 BP 185 EP 188 DI 10.1002/1521-3994(199908)320:4/5<185::AID-ASNA185>3.0.CO;2-K PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 266AD UT WOS:000084277700008 ER PT J AU White, NE Tananbaum, H AF White, NE Tananbaum, H TI The Constellation X-ray mission SO ASTRONOMISCHE NACHRICHTEN LA English DT Article DE X-rays; spectroscopy; constellation-X; abundances AB Constellation-X combines both the large collecting area and sensitive spectrometers required to obtain high spectral resolution, broad bandpass (0.25-40 keV) spectroscopy for all classes of X-ray sources, over a wide range of luminosity and redshift. It represents a major advance in sensitivity, providing up to a factor of 100 increase in throughput over currently planned high resolution (R > 300) X-ray; spectroscopy missions. Constellation-X is the X-ray equivalent of the Keck Telescope. When observations begin towards the end of the next decade, they will mark the start of a new era with high resolution X-ray spectra obtained for all classes of X-ray sources over a wide range of luminosity and distance. With its increased capabilities, Constellation-X will address many fundamental astrophysics questions such as observing the formation and evolution of clusters of galaxies; constraining the Baryon content of the Universe; determining the spin and mass of super massive black holes in AGN; and probing strong gravity in the vicinity of black holes. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP White, NE (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0004-6337 J9 ASTRON NACHR JI Astro. Nachr. PY 1999 VL 320 IS 4-5 BP 280 EP 281 DI 10.1002/1521-3994(199908)320:4/5<280::AID-ASNA280>3.0.CO;2-# PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 266AD UT WOS:000084277700043 ER PT J AU Finoguenov, A David, LP Ponman, TJ AF Finoguenov, A David, LP Ponman, TJ TI ASCA constraints on element production in groups and clusters of galaxies SO ASTRONOMISCHE NACHRICHTEN LA English DT Article ID INTRACLUSTER MEDIUM C1 Astrophysikal Inst Potsdam, D-14482 Potsdam, Germany. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. RP Finoguenov, A (reprint author), Astrophysikal Inst Potsdam, Sternwarte 16, D-14482 Potsdam, Germany. NR 4 TC 1 Z9 1 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0004-6337 J9 ASTRON NACHR JI Astro. Nachr. PY 1999 VL 320 IS 4-5 BP 286 EP 286 DI 10.1002/1521-3994(199908)320:4/5<286::AID-ASNA286>3.0.CO;2-C PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 266AD UT WOS:000084277700048 ER PT J AU Komossa, S Bohringer, H Huchra, J AF Komossa, S Bohringer, H Huchra, J TI Soft X-ray properties of LINERs SO ASTRONOMISCHE NACHRICHTEN LA English DT Article C1 Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Komossa, S (reprint author), Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. NR 3 TC 0 Z9 0 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0004-6337 J9 ASTRON NACHR JI Astro. Nachr. PY 1999 VL 320 IS 4-5 BP 301 EP 301 DI 10.1002/1521-3994(199908)320:4/5<301::AID-ASNA301>3.0.CO;2-N PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 266AD UT WOS:000084277700063 ER PT J AU Hearty, T Magnani, L Caillault, JP Neuhauser, R Schmitt, JHMM Stauffer, J AF Hearty, T Magnani, L Caillault, JP Neuhauser, R Schmitt, JHMM Stauffer, J TI A search for star formation in the translucent clouds MBM7 and MBM55 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE ISM : clouds; stars : formation ID T-TAURI STARS; LATITUDE MOLECULAR CLOUDS; MAIN-SEQUENCE STARS; H-ALPHA EMISSION; SOLAR-TYPE STARS; X-RAY SURVEYS; CIRRUS CLOUDS; LITHIUM ABUNDANCES; STELLAR CONTENT; CO OBSERVATIONS AB The star formation capability of two molecular clouds at high galactic latitude (\b\ > 30 degrees) is investigated. Possible pre-main sequence stars in and around the translucent clouds MBM7 and MBM55 have been identified via their X-ray emission by inspecting ROSAT All-Sky Survey observations of the clouds and environs and ROSAT pointed observations of the high-density cores within the clouds. Follow-up optical spectroscopy of the stellar X-ray sources with V less than or equal to 15.5 mag was conducted with the 1.5-m Fred Lawrence Whipple Observatory telescope to identify standard signatures of pre-main sequence stars (LiI lambda 6708 Angstrom absorption and H alpha emission). We found 11 stars which have lithium equivalent widths, W(Li), above our detection threshold. Three of the stars with lithium also have weak Ho? emission. Relative ages for the stars with lithium are estimated by their position on an W(Li) vs. T-eff diagram. A calibration derived from data for several clusters with known ages indicates the stars are older than the translucent high-latitude clouds. This conclusion is supported by a comparison with theoretical evolutionary tracks of the stars from our sample for which we have distance measurements from Hipparcos. We find it is unlikely that any of the X-ray active, lithium-rich stars we identified have formed in the clouds in question. Theoretical and observational arguments support this conclusion and render unlikely the possibility that low-extinction translucent clouds are the sites of star formation. C1 Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. Univ Hamburg, Hamburger Sternwarte, D-21029 Hamburg, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hearty, T (reprint author), Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. EM thearty@xray.mpe.mpg.de NR 88 TC 20 Z9 20 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 1999 VL 341 IS 1 BP 163 EP 173 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 154QV UT WOS:000077900700022 ER PT J AU Lo, KY Chen, HW Ho, PTP AF Lo, KY Chen, HW Ho, PTP TI A survey of molecular gas content of galaxies at 0.08 < z < 1.06 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE submillimeter; galaxies : ISM; galaxies : evolution; ISM : molecules ID CO EMISSION; CLOVERLEAF QUASAR; IRAS F10214+4724; REDSHIFT; CLOUDS; MASS AB The study of high redshift galaxies has made tremendous progress in the last few years. In order to understand their evolution, it is important to probe the gas content of distant "normal" galaxies beyond z similar to 0.3. We searched for CO emission from a sample of galaxies in the redshift range of 0.35 to 1.06. Given the current limited sensitivity, we can only place upper limits to the gas content of these progenitors to luminous field galaxies of similar to 3 x 10(11)M.. We also searched a sample of distant luminous IR galaxies and detected two new galaxies at z similar to 0.1. The upper limits to and the detection of CO emission from these distant galaxies are consistent with the suggested upper limit to galaxy masses of 10(12)M. posed by the cooling time argument. C1 Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Acad Sinica, Inst Astron & Astrophys, Taipei 115, Taiwan. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02128 USA. RP Lo, KY (reprint author), Max Planck Inst Extraterr Phys, Postfach 1603, D-85740 Garching, Germany. EM kyl@biaa.sinica.edu.tw NR 30 TC 9 Z9 9 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 1999 VL 341 IS 2 BP 348 EP 354 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 157QC UT WOS:000078072300011 ER PT J AU Micela, G Sciortino, S Harnden, FR Kashyap, V Rosner, R Prosser, CF Damiani, F Stauffer, J Caillault, JP AF Micela, G Sciortino, S Harnden, FR Kashyap, V Rosner, R Prosser, CF Damiani, F Stauffer, J Caillault, JP TI Deep ROSAT HRI observations of the Pleiades SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE X-rays : stars; stars : coronae; open clusters and associations : individual : Pleiades ID X-RAY SURVEY; STELLAR CORONAL COMPONENT; OPEN CLUSTER NGC-2516; N-LOG-S; ROTATIONAL VELOCITIES; STANDARD STARS; ALPHA-PERSEI; EINSTEIN; EMISSION; MEMBERS AB In a deep X-ray survey of the Pleiades open cluster, we use the ROSAT High Resolution Imager to explore a region of the cluster formerly surveyed with the PSPC. These new observations substantially improve upon both the sensitivity and the spatial resolution for this region of the Pleiades, allowing us to detect 18 cluster members not detected before and 16 members not included in the catalogs used in previous surveys. The high sensitivity of the present observations permits us to obtain more stringent upper limits for 72 additional members and also provides sufficient numbers of stars to enable us to explore the dependence of L(x) on stellar rotation for the slow rotators of the Pleiades. Using the new high sensitivity X-ray observations and the recent rotational measurements we discuss the activity-rotation relationship in the Pleiades solar type stars. We also present new photometric observations of optical counterparts of a number of X-ray sources detected in previous surveys but not yet identified. C1 Osserv Astron Palermo, I-90134 Palermo, Italy. Ctr Astrophys, Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. RP Micela, G (reprint author), Osserv Astron Palermo, Palazzo Normanni, I-90134 Palermo, Italy. EM gmicela@oapa.astropa.unipa.it; ssciortino@oapa.astropa.unipa.it; frh@cfa.harvard.edu; kashyap@cfa.harvard.edu; rrosner@oddjob.uchicago.edu; fdamiani@oapa.astropa.unipa.it; stauffer@cfa.harvard.edu; jpc@akbar.physast.uga.edu OI Damiani, Francesco/0000-0002-7065-3061 NR 67 TC 74 Z9 74 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 1999 VL 341 IS 3 BP 751 EP 767 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 161AT UT WOS:000078266100018 ER PT J AU Barret, D Grindlay, JE Harrus, IM Olive, JF AF Barret, D Grindlay, JE Harrus, IM Olive, JF TI An ASCA X-ray observation of 1E 1724-3045 in the globular cluster Terzan 2 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : individual : 1E 1724-3045; galaxy : globular clusters : individual : Terzan 2; X-rays : stars ID MASS; ACCRETION; BINARIES; SPECTRA AB The bright persistent X-ray source and type I X-ray burster 1E 1724-3045 located in the globular cluster Terzan 2 was observed by ASCA for about 10 ksec on September 24-25th, 1995 while it was in its hard state, with a luminosity of similar to 6 x 10(36) ergs s(-1) in the 0.5-10 keV band (d=7.7 kpc). The ASCA spectrum is hard, and reveals the presence of a soft component below 2-3 keV. When combined with non simultaneous RXTE/HEXTE data, we show that the ASCA spectrum can be adequately fitted by a Comptonization model for which the electron temperature is similar to 30 keV, the optical depth is similar to 3 for a spherical scattering cloud. The soft component carries off about 13%, and 35% of the 0.1-200 keV luminosity for a blackbody and disk blackbody fit respectively. It is more likely to arise from the accretion disk, whereas the hard Comptonized component is generated in a hot boundary layer interior to the disk. The column density measured towards the source (N-H similar to 1.0 x 10(22) cm(-2)) is consistent with the value expected from the optical reddening of the cluster. No emission lines were detected, and an upper limit of 30 eV for the equivalent width of a 6.4 keV line (sigma = 0.1 keV) has been derived. C1 UPS, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse 04, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Barret, D (reprint author), UPS, Ctr Etud Spatiale Rayonnements, 9 Ave Colonel Roche, F-31028 Toulouse 04, France. EM Didier.Barret@cesr.fr NR 29 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 JAN PY 1999 VL 341 IS 3 BP 789 EP 794 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 161AT UT WOS:000078266100021 ER PT J AU Haarsma, DB Hewitt, JN Lehar, J Burke, BF AF Haarsma, DB Hewitt, JN Lehar, J Burke, BF TI The radio wavelength time delay of gravitational lens 0957+561 SO ASTROPHYSICAL JOURNAL LA English DT Article DE distance scale; gravitational lensing; quasars : individual (0957 + 561); radio continuum : stars ID VLBI OBSERVATIONS; HUBBLE-CONSTANT; LIGHT-CURVE; QSO-0957+561; Q0957+561; SYSTEM; MODEL AB The gravitational lens 0957+561 was monitored with the Very Large Array from 1979 to 1997. The 6 cm light-curve data from 1995 to 1997 and the 4 cm data from 1990 to 1997 are reported here. At 4 cm the intrinsic source variations occur earlier and are twice as large as the corresponding variations at 6 cm. The VLBI core and jet components have different magnification factors, leading to different flux ratios for the varying and nonvarying portions of the VLA light curves. Using both the Press, Rybicki, & Hewitt Q (PRHQ) and dispersion statistical techniques, we determined the time delay, core flux ratio, and excess nonvarying B image flux density. The fits were performed for the 4 and 6 cm light curves, both individually and jointly, and we used Gaussian Monte Carlo data to estimate 68% statistical confidence levels. The delay estimates from each individual wavelength were inconsistent given the formal uncertainties, suggesting that there are unmodeled systematic errors in the analysis. We roughly estimate the systematic uncertainty in the joint result from the difference between the 6 and 4 cm results, giving 409 +/- 30 days for the PRHQ statistic and 397 +/- 20 days for the dispersion statistic. These results are consistent with the current optical time delay of 417 +/- 3 days, reconciling the long-standing difference between the optical and radio light curves and between different statistical analyses. The unmodeled systematic effects may also corrupt light curves for other lenses, and we caution that multiple events at multiple wavelengths may be necessary to determine an accurate delay in any lens system. Now that consensus has been reached regarding the time delay in the 0957+561 system, the most pressing issue remaining for determining H-o is a full understanding of the mass distribution in the lens. C1 Haverford Coll, Haverford, PA 19041 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Haarsma, DB (reprint author), Haverford Coll, Haverford, PA 19041 USA. NR 30 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 1999 VL 510 IS 1 BP 64 EP 70 DI 10.1086/306584 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NG UT WOS:000079157400007 ER PT J AU Feldmeier, JJ Brandt, WN Elvis, M Fabian, AC Iwasawa, K Mathur, S AF Feldmeier, JJ Brandt, WN Elvis, M Fabian, AC Iwasawa, K Mathur, S TI Heavy and complex X-ray absorption toward the nucleus of Markarian 6 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (Markarian 6); galaxies : ISM; galaxies : Seyfert; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; SEYFERT-GALAXIES; RADIO GALAXIES; EMISSION-LINE; SPECTROSCOPY; VARIABILITY; CONTINUUM; NGC-1068; NGC-4151; REGION AB We have used the ASCA satellite to make the first X-ray spectra of Mrk 6, a bright Seyfert 1.5 galaxy with complex and variable permitted lines, an ionization cone, and remarkable radio structures. Our 0.6-9.5 keV spectra penetrate to the black hole core of this Seyfert and reveal heavy and complex intrinsic X-ray absorption. Both total covering and single partial covering models fail to acceptably fit the observed absorption, and double partial covering or partial covering plus warm absorption appears to be required. The double partial covering model provides the best statistical fit to the data, and we measure large column densities of approximate to(3-20) x 10(22) cm(-2) irrespective of the particular spectral model under consideration. These X-ray columns are over an order of magnitude larger than expected based on observations at longer wavelengths. Our data suggest that most of the X-ray absorption occurs either in gas that has a relatively small amount of dust or in gas that is located within the broad-line region. The X-ray absorber may well be the putative "atmosphere" above the torus that collimates the ionization cone. We also detect an apparently broad 6.4 keV iron K alpha line, and we present optical spectra demonstrating that the optical emission lines were in a representative state during our ASCA observation. C1 Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. RP Feldmeier, JJ (reprint author), Penn State Univ, Dept Astron & Astrophys, 525 Davey Lab, University Pk, PA 16802 USA. RI Brandt, William/N-2844-2015; OI Brandt, William/0000-0002-0167-2453; Feldmeier, John/0000-0003-2908-2620 NR 60 TC 22 Z9 22 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 1999 VL 510 IS 1 BP 167 EP 177 DI 10.1086/306578 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NG UT WOS:000079157400015 ER PT J AU Esser, R Fineschi, S Dobrzycka, D Habbal, SR Edgar, RJ Raymond, JC Kohl, JL Guhathakurta, M AF Esser, R Fineschi, S Dobrzycka, D Habbal, SR Edgar, RJ Raymond, JC Kohl, JL Guhathakurta, M TI Plasma properties in coronal holes derived from measurements of minor ion spectral lines and polarized white light intensity SO ASTROPHYSICAL JOURNAL LA English DT Article DE solar wind; Sun : corona; Sun : UV radiation ID SPEED SOLAR-WIND; ALFVEN WAVES; 2-FLUID MODEL; ACCELERATION; TEMPERATURE; REGION AB Recent observations of the Ly alpha lambda 1216, Mg x lambda 625, and O VI lambda 1038 spectral lines carried out with the Ultraviolet Coronagraph Spectrometer (UVCS) on board SOHO at distances in the range 1.35-2.1 R-s in the northern coronal hole are used to place limits on the turbulent wave motions of the background plasma and the thermal motions of the protons and Mg+9 and O+5 ions. Limits on the turbulent wave motion are estimated from the measured line widths and electron densities derived from white light coronagraph observations, assuming WKB approximation at radial distances-covered by the observations. It is shown that the contribution of the turbulent wave motion to the widths of the measured spectral lines is small compared to thermal broadening. The observations show that the proton temperature slowly increases between 1.35 and 2.7 R-s and does not exceed 3 x 10(6) K in that region. The temperature of the minor ions exceeds the proton temperature at all distances, but the temperatures are neither mass proportional nor mass-to -charge proportional. It is shown, for the first time, that collision times between protons and minor ions are small compared to the solar wind expansion times in the inner corona. At 1.35 R-s the expansion time exceeds the proton Mg+9 collision time by more than an order of magnitude. Nevertheless, the temperature of the Mg ions is significantly larger than the proton temperature, which indicates that the heating mechanism has to act on timescales faster than minutes. When the expansion time starts to exceed the collision times a rapid increase of the O+5 ion spectral line width is seen. This indicates that the heavier and hotter ions lose energy to the protons as long as collision frequencies are high, and that the ion spectral line width increases rapidly as soon as this energy loss stops. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Esser, R (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NR 28 TC 151 Z9 153 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 1 PY 1999 VL 510 IS 1 BP L63 EP L67 DI 10.1086/311786 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NH UT WOS:000079157500015 ER PT J AU Kohl, JL Esser, R Cranmer, SR Fineschi, S Gardner, LD Panasyuk, AV AF Kohl, JL Esser, R Cranmer, SR Fineschi, S Gardner, LD Panasyuk, AV TI EUV spectral line profiles in polar coronal holes from 1.3 to 3.0 R-circle dot SO ASTROPHYSICAL JOURNAL LA English DT Article DE line : profiles; solar wind; Sun : corona; Sun : UV radiation ID SOLAR-WIND; ACCELERATION AB Spectral line profiles have been measured for H I lambda 1216, O VI lambda lambda 1032, 1037, and Mg x lambda 625 in a polar coronal hole observed during 1997 September 15-29, at projected heliographic heights rho between 1.34 and 2.0 R.. Observations of H I lambda 1216 and the O VI doublet from 1997 January for rho = 1.5-3.0 R. are provided for comparison. The O VI lines are well fit to a narrow and broad component which appear to be associated with regions of higher and lower spectral radiance, respectively. The narrow components dominate at low heights and become a small fraction of the lines at higher heights. Mg x lambda 625 is observed to have a narrow component at rho = 1.34 R. which accounts for only a small fraction of the observed spectral radiance. In the case of the broad components, the values of v(1/e) for O VI are only slightly larger than those for H I at rho = 1.34 R. but are significantly larger at rho = 1.5 R. and much larger for rho > 1.75 R.. In contrast, the Mg x values are less than those of H I up to 1.75 and then increase rapidly up to at least rho = 2.0 R. but never reach the values of O VI. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Osservatorio Astron Torino, I-10025 Pino Torinese, Italy. Univ Florence, I-50125 Florence, Italy. RP Kohl, JL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 16 TC 102 Z9 103 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 JAN 1 PY 1999 VL 510 IS 1 BP L59 EP L62 DI 10.1086/311793 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NH UT WOS:000079157500014 ER PT J AU Lim, J Ho, PTP AF Lim, J Ho, PTP TI Violent tidal disruptions of atomic hydrogen gas in quasar host galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : interactions; galaxies : Seyfert; quasars : general; radio lines : galaxies ID H-I; REDSHIFT; DYNAMICS; EMISSION; NUCLEI; QSOS AB Violent galactic encounters or mergers are the leading contenders for triggering luminous quasar activity at low redshifts: such interactions can lead to the concentration of gas in the host galactic nucleus, thus fueling the suspected central supermassive black hole. Although optical images show a number of violently interacting systems, in many cases, the evidence for such interactions is only circumstantial (e.g., asymmetric optical morphologies, projected nearby companion galaxies) or not at all apparent. Here we image quasar host galaxies for the first time in the redshifted 21 cm line emission of neutral atomic hydrogen (H I) gas, which, in nearby galaxies, has proved to be a particularly sensitive as well as enduring tracer of tidal interactions. The three quasars studied have different optical environments that are normally seen around low-redshift quasars, ranging from a perhaps mildly interacting system to a relatively undisturbed host with a projected neighboring galaxy to an isolated and apparently serene host galaxy. By contrast with their optical appearances, all three quasar host galaxies exhibit ongoing or remnant tidal H I disruptions tracing galactic encounters or mergers. These observations demonstrate the utility of H I at revealing tidal interactions in quasar host galaxies and, combined with optical studies, provide a fuller understanding of the likely stage of the interaction. C1 Acad Sinica, Inst Astron & Astrophys, Taipei 115, Taiwan. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Lim, J (reprint author), Acad Sinica, Inst Astron & Astrophys, POB 1-87, Taipei 115, Taiwan. EM jlim@asiaa.sinica.edu.tw; ho@cfa.harvard.edu NR 28 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 JAN 1 PY 1999 VL 510 IS 1 BP L7 EP L10 DI 10.1086/311801 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NH UT WOS:000079157500002 ER PT J AU Pen, UL AF Pen, UL TI Heating of the intergalactic medium SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : theory; diffuse radiation; supernovae : general; X-rays : general ID CLUSTERS AB Using the cosmic virial theorem, Press-Schechter analysis, and numerical simulations, we compute the expected X-ray background (XRB) from the diffuse: intergalactic medium (IGM) with the clumping factor expected from gravitational shock heating. The predicted fluxes and temperatures are ruled out by the observed XRB. The predicted clumping can be reduced by entropy injection. The required energy is computed from the two-point correlation function, as well as from Press-Schechter formalisms. The minimal energy injection of 1 keV per nucleon excludes radiative or gravitational heating as a primary energy source. We argue that the IGM must have been heated through violent mechanical processes such as massive supernova bursts. If the heating proceeded through supernova explosions, it likely proceeded in bursts which may be observable in high-redshift supernova searches. Within our model, we reproduce the observed cluster luminosity-temperature relation with energy injection of 1 keV per nucleon if this injection is assumed to be uncorrelated with the local density. These parameters predict that the diffuse IGM soft XRB has a temperature of similar to 1 keV with a flux near 10 keV cm(-2) s(-1) sr(-1) keV(-1), which may be detectable in the near future. C1 Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Pen, UL (reprint author), Canadian Inst Theoret Astrophys, 60 St George St, Toronto, ON M5S 3H8, Canada. NR 24 TC 71 Z9 71 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 1999 VL 510 IS 1 BP L1 EP L5 DI 10.1086/311799 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NH UT WOS:000079157500001 ER PT J AU Woo, R Habbal, SR AF Woo, R Habbal, SR TI Imprint of the Sun on the solar wind SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona ID ELECTRON-DENSITY FLUCTUATIONS; SPACECRAFT; SPECTRUM; STREAMS; CORONA AB Observations of the inner corona in polarized brightness by the Mauna Loa Mk III K-coronameter at 1.15 R. and soft X-rays by Yohkoh at 1.03 R. are combined with 1995 Ulysses radio occultation measurements of the solar wind to demonstrate that the signatures of the coronal hole boundary, active regions, and bright points are present in the heliocentric distance range of 20-30 R.. The existence of these signatures in the brightness of the corona (observed by ranging measurements) and the contrast of the small-scale raylike structures comprising the corona (observed by Doppler scintillation measurements) at such distances can readily be accounted for by open field lines rooted within the complex magnetic structures of the quiet Sun, active regions, and bright points. Hence, with the exception of the small volume of interplanetary space occupied by the heliospheric current sheet that evolves from coronal streamers within a few solar radii of the Sun, small-scale raylike structures carry the imprint of the different density structures of the solar disk approximately radially into the heliosphere. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 30 TC 28 Z9 29 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 JAN 1 PY 1999 VL 510 IS 1 BP L69 EP L72 DI 10.1086/311789 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NH UT WOS:000079157500016 ER PT J AU Pen, UL AF Pen, UL TI Analytical fit to the luminosity distance for flat cosmologies with a cosmological constant SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE cosmology, theory; distance scale AB We present a fitting formula for the luminosity and angular diameter distances in cosmological models with pressureless matter, a cosmological constant, and zero spatial curvature. The formula has a relative error of less than 0.4% for 0.2 < Omega(0) < 1 for any redshift and a global relative error of less than 4% for any choice of parameters. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Pen, UL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 5 TC 69 Z9 71 U1 1 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 JAN PY 1999 VL 120 IS 1 BP 49 EP 50 DI 10.1086/313167 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 177DT UT WOS:000079192700003 ER PT J AU Antonelli, LA Wilkes, BJ Fiore, F Matt, G Mathur, S Nicastro, F AF Antonelli, LA Wilkes, BJ Fiore, F Matt, G Mathur, S Nicastro, F TI The BeppoSAX observation of the Seyfert 1.9 galaxy ESO103-G35 SO ASTROPHYSICAL LETTERS & COMMUNICATIONS LA English DT Article; Proceedings Paper CT 3rd Integral Workshop on the Extreme Universe CY SEP 14-18, 1998 CL TAROMINA, ITALY DE AGN; ESO103-G35; x-rays; BeppoSAX ID ACTIVE GALAXIES; RAY; ABSORPTION AB We present results from BeppoSAX observations of the Seyfert 1.9 Galaxy ESO103-G35. The LEGS, MECS and PDS spectra (0.1-200 keV) allows us to better understand the nature of this object. We find that the spectra can be described by a powerlaw with a photon index typical of a Seyfert 1 with a cutoff at high energies and a large absorption column density, a cold iron line resolved by the MECS, a reflection component and a soft excess. These results show that this Seyfert 1.9 galaxy can be considered as an edge-on Seyfert 1, in agreement with AGN Unification Schemes. C1 Osservatorio Astron Roma, I-00040 Monte Porzio Catone, Italy. BeppoSAX Sci Data Ctr, I-00131 Rome, Italy. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Roma Tre, I-00146 Rome, Italy. CNR, Ist Astrofis Spaziale, I-00133 Rome, Italy. RP Antonelli, LA (reprint author), Osservatorio Astron Roma, Via Frascati 33, I-00040 Monte Porzio Catone, Italy. NR 15 TC 0 Z9 0 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0888-6512 J9 ASTROPHYS LETT COMM JI Astrophys. Lett. Comm. PY 1999 VL 39 IS 1-6 BP 553 EP 556 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357NR UT WOS:000089508200019 ER PT J AU Nicastro, F Fiore, F Matt, G AF Nicastro, F Fiore, F Matt, G TI The high energy resolution view of warm absorbers SO ASTROPHYSICAL LETTERS & COMMUNICATIONS LA English DT Article; Proceedings Paper CT 3rd Integral Workshop on the Extreme Universe CY SEP 14-18, 1998 CL TAROMINA, ITALY AB A number of absorption features are expected to be visible in high energy resolution spectra of type 1 AGN with ionized gas along the line of sight (so called "warm absorbers"). These include photoelectric absorption K and L edges along with many strong K alpha, K beta and L resonance absorption lines from the most abundant elements. We present detailed simulations of our "photoelectric + resonant absorption" model with the high energy resolution gratings and calorimeters of AXAF, XMM and Constellation-X, and discuss the relevant physics which can be addressed with the new generation of X-ray spectrometers. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CNR, Ist Astrofis Spaziale, Rome, Italy. Osservatorio Astron Monteporzio, Monte Porzio Catone, Italy. Univ Roma Tre, Rome, Italy. RP Nicastro, F (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0888-6512 J9 ASTROPHYS LETT COMM JI Astrophys. Lett. Comm. PY 1999 VL 39 IS 1-6 BP 565 EP + PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357NR UT WOS:000089508200022 ER PT J AU Giommi, P Fiore, F Perri, M AF Giommi, P Fiore, F Perri, M TI X-ray surveys SO ASTROPHYSICAL LETTERS & COMMUNICATIONS LA English DT Article; Proceedings Paper CT 3rd Integral Workshop on the Extreme Universe CY SEP 14-18, 1998 CL TAROMINA, ITALY ID DEEP ROSAT SURVEY; NUMBER COUNTS RELATIONSHIP; OPTICAL-IDENTIFICATION; LOCKMAN FIELD; ASCA; POPULATIONS; GALAXIES; SPECTRA; SKY AB A review of recent developments in the field of X-ray surveys, espeicially in the hard (2-10 and 5-10 keV) bands, is given. A new detailed comparisons between the measurements in the hard band and extrapolations from ROSAT counts, that takes into proper account the observed distribution of spectral slopes, is presented. Direct comparisons between deep ROSAT and BeppoSAX images show that most hard X-ray sources are also detected at soft X-ray energies. This may indicate that heavily cutoff sources, that not be detectable in the ROAST band but are expected in alrge numbers from unified AGN schemes, are in fact detected because of the emerging of either non-linear components, or of reflected, or partially transmitted nuclear X-rays. These soft components may complictae the estimation of the soft X-ray luminosity function and cosmological evolution of AGN. C1 BeppoSAX Sci Data Ctr, Rome, Italy. Osservatorio Astron Roma, I-00040 Monte Porzio Catone, Italy. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Giommi, P (reprint author), BeppoSAX Sci Data Ctr, Rome, Italy. NR 23 TC 0 Z9 0 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0888-6512 J9 ASTROPHYS LETT COMM JI Astrophys. Lett. Comm. PY 1999 VL 39 IS 1-6 BP 641 EP 648 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357NR UT WOS:000089508200038 ER PT J AU Fiore, F Giommi, P La Franca, F Matt, G Perola, GC Comastri, A Molendi, S Elvis, M Gioia, I Tamburelli, F Ricci, D Pompilio, F AF Fiore, F Giommi, P La Franca, F Matt, G Perola, GC Comastri, A Molendi, S Elvis, M Gioia, I Tamburelli, F Ricci, D Pompilio, F TI The BeppoSAX "HELLAS" survey SO ASTROPHYSICAL LETTERS & COMMUNICATIONS LA English DT Article; Proceedings Paper CT 3rd Integral Workshop on the Extreme Universe CY SEP 14-18, 1998 CL TAROMINA, ITALY DE X-rays; cosmic X-ray background; AGN ID DEEP ROSAT FIELDS; X-RAY SOURCES; ASCA OBSERVATIONS; LOCKMAN FIELD; GALAXIES AB The BeppoSAX High Energy Llarge Area Survey (HELLAS) covers the 5-10 keV band and has so far catalogued about 180 sources over 50 deg(2) of sky. After correction for the non uniform sky coverage we find 16 +/- 5 sources deg(-2) with F5-10keV greater than or equal to 5 X 10(-14) erg cm(-2) s(-1) and resolve 30-40% of the hard 5-10 keV Cosmic X-ray Background (XRB). Optical identification of a first small sample of sources show that most (12 out of 14) are AGN. Seven of these AGN show evidence of absorption/extintion in X-ray/optical. These results support to the scenario in which the hard XRB is made by obscured AGN. C1 BeppoSax Sci Data Ctr, I-00131 Rome, Italy. Osservatorio Astron Roma, I-00040 Monte Porzio Catone, Italy. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Roma 3, I-00146 Rome, Italy. Osservatorio Astron Bologna, I-40127 Bologna, Italy. CNR, IFCTR, I-20133 Milan, Italy. CNR, IRA, I-40129 Bologna, Italy. Astron Inst, Honolulu, HI 96822 USA. RP Fiore, F (reprint author), BeppoSax Sci Data Ctr, Via Corcolle 19, I-00131 Rome, Italy. RI Gioia, Isabella/B-6982-2012; La Franca, Fabio/G-9631-2012; Comastri, Andrea/O-9543-2015 OI Gioia, Isabella/0000-0003-3127-498X; Comastri, Andrea/0000-0003-3451-9970 NR 16 TC 0 Z9 0 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0888-6512 J9 ASTROPHYS LETT COMM JI Astrophys. Lett. Comm. PY 1999 VL 39 IS 1-6 BP 657 EP 660 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357NR UT WOS:000089508200040 ER PT J AU Lund, N Budtz-Jorgensen, C Westergaard, NJ Hornstrup, A Rasmussen, IL Laursen, S Kristensen, R Mogensen, PB Andersen, KH Rasmussen, I Polny, J Frederiksen, P Lauridsen, B Omo, K Jonasson, P Kamarinen, V Andersson, T Vilhu, O Huovelin, J Costa, E Feroci, M Rubini, A Morelli, E Morbidini, A Frontera, F Zavattini, C Carassiti, V Morawski, M Juchnikowski, G Reglero, V Peris, J Collado, V Rodrigo, JM Perez, F Requena, JL Larsson, S Svensson, R Zdziarski, A Schnopper, HW AF Lund, N Budtz-Jorgensen, C Westergaard, NJ Hornstrup, A Rasmussen, IL Laursen, S Kristensen, R Mogensen, PB Andersen, KH Rasmussen, I Polny, J Frederiksen, P Lauridsen, B Omo, K Jonasson, P Kamarinen, V Andersson, T Vilhu, O Huovelin, J Costa, E Feroci, M Rubini, A Morelli, E Morbidini, A Frontera, F Zavattini, C Carassiti, V Morawski, M Juchnikowski, G Reglero, V Peris, J Collado, V Rodrigo, JM Perez, F Requena, JL Larsson, S Svensson, R Zdziarski, A Schnopper, HW TI JEM-X: The X-ray monitor on INTEGRAL SO ASTROPHYSICAL LETTERS & COMMUNICATIONS LA English DT Article; Proceedings Paper CT 3rd Integral Workshop on the Extreme Universe CY SEP 14-18, 1998 CL TAROMINA, ITALY DE X-ray astronomy; INTEGRAL; JEM-X; sensitivity AB The INTEGRAL X-ray monitor, JEM-X, (together with the two gamma ray instruments, SPI and IBIS) will provide simultaneous imaging with arcminute angular resolution in the 3-60 keV band. The unique angular resolution and low energy response of JEM-X will play a crucial role in the detection and identification of gamma ray sources as well as in the analysis and scientific interpretation of the combined X-ray and gamma ray data. JEM-X is a coded aperture X-ray telescope consisting of two identical detectors. Each detector has a sensitive area of 500 cm(2), and views the sky (6.6 deg FOV, FWHM) through its own coded aperature mask. The coded cm masks are located 3.4 m above the detector windows. The detector field of view is constrained by X-ray collimators. C1 Danish Space Res Inst, Copenhagen, Denmark. Metorex, Espoo, Finland. Univ Helsinki, Helsinki, Finland. CNR, Inst Astrofis, Rome, Italy. Univ Ferrara, I-44100 Ferrara, Italy. Polish Acad Sci, Space Res Ctr, PL-01237 Warsaw, Poland. Univ Valencia, Valencia, Spain. Stockholm Observ, Stockholm, Sweden. Copernicus Astron Ctr, Warsaw, Poland. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Lund, N (reprint author), Danish Space Res Inst, Copenhagen, Denmark. NR 3 TC 1 Z9 1 U1 0 U2 2 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0888-6512 J9 ASTROPHYS LETT COMM JI Astrophys. Lett. Comm. PY 1999 VL 39 IS 1-6 BP 807 EP 813 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357NR UT WOS:000089508200073 ER PT J AU White, NE Tananbaum, H AF White, NE Tananbaum, H TI The Constellation X-ray mission SO ASTROPHYSICAL LETTERS & COMMUNICATIONS LA English DT Article; Proceedings Paper CT 3rd Integral Workshop on the Extreme Universe CY SEP 14-18, 1998 CL TAROMINA, ITALY DE X-rays; spectroscopy; constellation-X; abundances AB Constellation-X is the X-ray equivalent of the Keck Telescope. When observations begin towards the end of the next decade, they will mark the start of anew era with high resolution X-ray spectra obtained for all classes of X-ray sources over a wide range of luminosity and distance. With its increased capabilities, Constellation-X will address many fundamental astrophysics questions such as observing the formation and evolution of clusters of galaxies; constraining the Baryon content of the Universe;determining the spin and mass of super massive black holes in AGN; and probing strong gravity in the vicinity of black holes. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP White, NE (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0888-6512 J9 ASTROPHYS LETT COMM JI Astrophys. Lett. Comm. PY 1999 VL 39 IS 1-6 BP 933 EP 936 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357NR UT WOS:000089508200103 ER PT J AU Barret, D Boirin, L Olive, JF Grindlay, JE Bloser, PF Swank, JH Smale, AP AF Barret, D Boirin, L Olive, JF Grindlay, JE Bloser, PF Swank, JH Smale, AP TI Discovery of high frequency quasi-periodic oscillations in 4U1915-05 SO ASTROPHYSICAL LETTERS & COMMUNICATIONS LA English DT Article; Proceedings Paper CT 3rd Integral Workshop on the Extreme Universe CY SEP 14-18, 1998 CL TAROMINA, ITALY DE X-ray binaries; neutron star : individual 4U1915-05 AB The type I X-ray burster and dipper 4U1915-05 (also known as XB1916-053) was monitored by the Rossi X-ray Timing Explorer between February and October, 1996. The source was observed in various spectral states; the highest luminosity state (L-X similar to 1.5 x 10(37) ergs s(-1), 10 kpc, 1-20 keV) is associated with a soft spectrum, whereas for the lower luminosity state (down to similar to 5 x 10(36)ergs s(-1)) the spectrum is significantly harder. Using the high time resolution data provided by the Proportional Counter Array (PCA), we have discovered High-Frequency quasi-Periodic Oscillations (HFQPOs) in the persistent X-ray emission of 4U1915-05 while its luminosity was similar to 8 x 10(36)ergs s(-1). The QPO frequency ranges from 600 Hz up to similar to 1000 nz, with typical Full Width at Half Maximum (FWHM) similar to 50 - 100 Hz and Root Mean Squared (RMS) values similar to 15%. fn addition, by using the "shift and add" technique, we have detected a twin HFQPO (5.5 sigma level) separated from the main peak by similar to 355 Hz. 4U1915-05 is the eighth Atoll source displaying simultaneous twin HFQPOs, Based on current knowledge of HFQPO sources, our observations suggest that 4U1915-05 might contain a 2.8 (or 5.6) millisecond rotating neutron star. C1 UPS, CNRS, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse 04, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Barret, D (reprint author), UPS, CNRS, Ctr Etud Spatiale Rayonnements, 9 Ave Colonel Roche, F-31028 Toulouse 04, France. RI Swank, Jean/F-2693-2012 NR 8 TC 0 Z9 0 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0888-6512 J9 ASTROPHYS LETT COMM JI Astrophys. Lett. Comm. PY 1999 VL 38 IS 1-6 BP 73 EP 76 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357NP UT WOS:000089508000019 ER PT J AU Vilhu, O Alha, L Malmivaara, K Huovelin, J Poutanen, J Nevalainen, J AF Vilhu, O Alha, L Malmivaara, K Huovelin, J Poutanen, J Nevalainen, J TI Broad band disc-corona modelling of GRS 1915+105 SO ASTROPHYSICAL LETTERS & COMMUNICATIONS LA English DT Article; Proceedings Paper CT 3rd Integral Workshop on the Extreme Universe CY SEP 14-18, 1998 CL TAROMINA, ITALY DE accretion; black hole physics; stars : individual : GRS 1915+105 ID RAY AB We examined two possible spectral models for describing the radiative phenomena in the vicinity of the Galactic black hole candidate GRS 1915 + 105. One of the models is hybrid (thermal/nonthermal) and the other one a thermal sombrero. The data analysed were obtained by RXTE (PCA and HEXTE) and the CGRO (OSSE). The timings of the observations were mutually syncronized between PCA and HEXTE. The OSSE data were cumulative with a total duration of 5 days close to the 3 hours of RXTE observations. This enabled us to make broad band spectral fits in the energy range 2.0-400 keV requiring a non-thermal tail. Simultaneous observations are required because of the highly variable X-ray luminosity. Further, we simulated the models through the responses of the JEM-X and IBIS detectors onboard INTEGRAL. We conclude that the INTEGRAL instruments are well tailored to study the physics of near-Eddington accretion. C1 Univ Helsinki Observ, SF-00130 Helsinki, Finland. Stockholm Observ, S-13336 Saltsjobaden, Sweden. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Vilhu, O (reprint author), Univ Helsinki Observ, SF-00130 Helsinki, Finland. RI Poutanen, Juri/H-6651-2016; OI Poutanen, Juri/0000-0002-0983-0049; Huovelin, Juhani/0000-0002-6276-5776 NR 7 TC 1 Z9 1 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0888-6512 J9 ASTROPHYS LETT COMM JI Astrophys. Lett. Comm. PY 1999 VL 38 IS 1-6 BP 241 EP 244 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357NP UT WOS:000089508000060 ER PT J AU Fazio, GG Eisenhardt, P Huang, JS AF Fazio, GG Eisenhardt, P Huang, JS TI The Space Infrared Facility (SIRTF): A new probe for study of the birth and evolution of galaxies in the early Universe SO ASTROPHYSICS AND SPACE SCIENCE LA English DT Article AB The Space Infrared Telescope Facility (SIRTF) is the fourth and final element in NASA's family of orbiting "Great Observatories. SIRTF will offer order-of-magnitude improvements in capability over existing programs in the wavelength region between 3 and 180 microns. The combination of large-format detector arrays, with the intrinsic sensitivity of a cryogenic telescope, and the high sky visibility of a solar orbit, makes SIRTF an ideal instrument to carry out a number of very significant surveys to study the birth and evolution of galaxies in the early Universe. More than 75% of SIRTF's observing time will be available to the worldwide scientific community, with the first call for proposals in July, 2000. SIRTF will be launched in December 2001, with an anticipated lifetime of 5 years. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Fazio, GG (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 3 TC 3 Z9 3 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0004-640X J9 ASTROPHYS SPACE SCI JI Astrophys. Space Sci. PY 1999 VL 269 BP 541 EP 548 DI 10.1023/A:1017035500154 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 323VG UT WOS:000087585200047 ER PT J AU Gingerich, O AF Gingerich, O TI Report on the progress in stellar evolution to 1950 SO ASTROPHYSICS AND SPACE SCIENCE LA English DT Article 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 35 TC 0 Z9 0 U1 1 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0004-640X J9 ASTROPHYS SPACE SCI JI Astrophys. Space Sci. PY 1999 VL 267 IS 1-4 BP 3 EP 21 DI 10.1023/A:1002711422064 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 320UY UT WOS:000087419800004 ER PT J AU Kuijken, K AF Kuijken, K TI Dark matter in the Milky Way SO ASTROPHYSICS AND SPACE SCIENCE LA English DT Article ID SURFACE MASS DENSITY; GALACTIC DISK; LUMINOSITY FUNCTION; GALAXY; STARS; HALO; SUN; CONSTRAINTS; EVOLUTION; MODEL C1 Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kapteyn Astron Inst, POB 800, NL-9700 AV Groningen, Netherlands. EM kuijken@astro.rug.nl NR 31 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0004-640X EI 1572-946X J9 ASTROPHYS SPACE SCI JI Astrophys. Space Sci. PY 1999 VL 267 IS 1-4 BP 217 EP 226 DI 10.1023/A:1002716902017 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 320UY UT WOS:000087419800021 ER PT J AU Fischer, J Luhman, ML Satyapal, S Greenhouse, MA Stacey, GJ Bradford, CM Lord, SD Brauher, JR Unger, SJ Clegg, PE Smith, HA Melnick, G Colbert, JW Malkan, MA Spinoglio, L Cox, P Harvey, V Suter, JP Strelnitski, V AF Fischer, J Luhman, ML Satyapal, S Greenhouse, MA Stacey, GJ Bradford, CM Lord, SD Brauher, JR Unger, SJ Clegg, PE Smith, HA Melnick, G Colbert, JW Malkan, MA Spinoglio, L Cox, P Harvey, V Suter, JP Strelnitski, V TI ISO FAR-IR spectroscopy of IR-bright galaxies and ULIRGs SO ASTROPHYSICS AND SPACE SCIENCE LA English DT Article; Proceedings Paper CT Workshop on Ulraluminous Galaxies - Monsters of Babies CY SEP 20-26, 1998 CL BAVARIA, GERMANY SP Max Planck Inst Extraterestr Physik DE infrared-bright galaxies; ultraluminous galaxies; far-infrared spectra; starbursts; interstellar medium ID LONG-WAVELENGTH SPECTROMETER; NGC-1068 AB Based on far-infrared spectroscopy of a small sample of nearby infrared-bright and ultraluminous infrared galaxies (ULIRGs) with the ISO Long Wavelength Spectrometer(1) we find a dramatic progression in ionic/atomic fine-structure emission line and molecular/atomic absorption line characteristics in these galaxies extending from strong [O III]52,88 mu m and [N III]57 mu m line emission to detection of only faint [C II]158 mu m line emission from gas in photodissociation regions in the ULIRGs. The molecular absorption spectra show varying excitation as well, extending from galaxies in which the molecular population mainly occupies the ground state to galaxies in which there is significant population in higher levels. In the case of the prototypical ULIRG, the merger galaxy Arp 220, the spectrum is dominated by absorption lines of OH, H2O, CH, and [O I]. Low [O III]88 mu m line flux relative to the integrated far-infrared flux correlates with low excitation and does not appear to be due to far-infrared extinction or to density effects. A progression toward soft radiation fields or very dusty H II regions may explain these effects. C1 USN, Res Lab, Washington, DC 20375 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. CALTECH, IPAC, Pasadena, CA 91125 USA. Univ London Queen Mary & Westfield Coll, London E1 4NS, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Los Angeles, Dept Astron, Los Angeles, CA 90024 USA. CNR, Ist Fis Spazio Interplanetario, Rome, Italy. Inst Astron Spatiale, Orsay, France. Maria Mitchell Observ, Nantucket, MA USA. RP Fischer, J (reprint author), USN, Res Lab, Washington, DC 20375 USA. OI Spinoglio, Luigi/0000-0001-8840-1551 NR 21 TC 41 Z9 41 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 1999 VL 266 IS 1-2 BP 91 EP 98 DI 10.1023/A:1002641429502 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 312MM UT WOS:000086947100015 ER PT B AU Hooper, E Wilkes, B McLeod, K McDowell, J Elvis, M Malkan, M Lonsdale, C Impey, C AF Hooper, E Wilkes, B McLeod, K McDowell, J Elvis, M Malkan, M Lonsdale, C Impey, C BE Bicay, M Beichman, CA Cutri, RM Madore, BF TI The USISO key project on quasars SO ASTROPHYSICS WITH INFRARED SURVEYS: A PRELUDE TO SIRTF SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Astrophysics with Infrared Surveys - A Prelude to SIRTF CY JUN 22-24, 1998 CL CALIFORNIA INST TECHNOL, PASADENA, CA SP NASA Off Space Sci, SIRTR Sci Ctr, Infrared Processing & Anal Ctr, Caltech Off Public Events, SIRTF Project Off JPL, Lockheed Martin Missiles & Space, Ball Aerosp Technol Corp HO CALIFORNIA INST TECHNOL C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hooper, E (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 6 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 1-58381-001-3 J9 ASTR SOC P PY 1999 VL 177 BP 153 EP 156 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN89F UT WOS:000083362400022 ER PT B AU Fazio, GG Hora, JL Stauffer, JR Eisenhardt, P AF Fazio, GG Hora, JL Stauffer, JR Eisenhardt, P BE Bicay, M Beichman, CA Cutri, RM Madore, BF TI Surveys with SIRTF and IRAC SO ASTROPHYSICS WITH INFRARED SURVEYS: A PRELUDE TO SIRTF SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Astrophysics with Infrared Surveys - A Prelude to SIRTF CY JUN 22-24, 1998 CL CALIFORNIA INST TECHNOL, PASADENA, CA SP NASA Off Space Sci, SIRTR Sci Ctr, Infrared Processing & Anal Ctr, Caltech Off Public Events, SIRTF Project Off JPL, Lockheed Martin Missiles & Space, Ball Aerosp Technol Corp HO CALIFORNIA INST TECHNOL ID TELESCOPE-FACILITY SIRTF AB SIRTF will be the first mission to combine the high sensitivity achievable from a cryogenic space telescope with the imaging and spectroscopic power of the new generation of infrared detector arrays. Within its lifetime, SIRTF will have the capability to conduct an extensive number of survey programs and be able to perform follow-up observations of the sources discovered. We discuss in detail one of SIRTF's focal plane instruments, the Infrared Array Camera (IRAC), and its capabilities to carry out such surveys. Two of the mast important scientific objectives of IRAC will be to carry out surveys to study galaxy formation and evolution in the early Universe, and to search for brown dwarfs and superplanets. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Fazio, GG (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 3 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 1-58381-001-3 J9 ASTR SOC P PY 1999 VL 177 BP 462 EP 472 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN89F UT WOS:000083362400071 ER PT S AU Karovska, M AF Karovska, M BE LeBertre, T Lebre, A Waelkens, C TI Fifteen years of high angular resolution studies of Mira's atmosphere SO ASYMPTOTIC GIANT BRANCH STARS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 191st Symposium of the International-Astronomical-Union CY AUG 27-SEP 01, 1998 CL MONTPELLIER, FRANCE SP Int Astron Union, Montpellier Univ Sci & Technol, CNRS AB I describe here results from high-angular resolution imaging studies of o Ceti (Mira). In 1983, we discovered that the atmosphere of the prototype of Mira-type variables is not symmetric. Since then, a number of multiwavelength high-angular resolution observations have confirmed the presence of asymmetries in Mira's atmosphere, and detected asymmetries in the atmospheres of other Mira-type variables. The high-angular resolution images of Mira obtained over the past fifteen years, including recent HST observations, show that the strength and shape of the asymmetries change as a function of wavelength and time. Plausible mechanisms for these asymmetries include hot spots, nonspherical pulsations, interaction with the companion and bipolar outflow. The presence of asymmetries in Miras could have serious impact on evolutionary models, and on the development of model atmospheres. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Karovska, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 9 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 0074-1809 BN 1-886733-90-2 J9 IAU SYMP PY 1999 IS 191 BP 139 EP 143 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU32Z UT WOS:000175704800017 ER PT J AU Isler, ML Isler, PR Whitney, BM AF Isler, ML Isler, PR Whitney, BM TI Species limits in antbirds (Passeriformes : Thamnophilidae): The Myrmotherula surinamensis complex SO AUK LA English DT Article ID FORMICARIIDAE; SYSTEMATICS; THAMNOMANES; BEHAVIOR AB Current species-level taxonomy of Neotropical birds is in need of reassessment but lacks objective methodology and criteria for the ranking of allopatric populations. Previously (Isler et al. 1998), through empirical analysis of pairs of syntopic species, we developed methods and standards for employing vocalizations in determining species limits in the family Thamnophilidae. Building on this study, we now propose procedures for integrating vocal characters with morphology and geographic distribution in making species determinations in thamnophilids. We applied this methodology to populations of antwrens in the Myrmotherula surinamensis complex (including three subspecies of M. surinamensis and M. cherriei). Four diagnostically differentiated populations were identified, all of which corresponded to named taxa. Each population (some of which are narrowly sympatric) was distinguished unambiguously by morphology and vocalizations. Under these objective and conservative standards, we recommend that Myrmotherula surinamensis, M. multostriata, M. pacifica, and M. cherriei be recognized as distinct species. The level of differentiation found between M. surinamensis and M. multostriata illustrates the minimum threshold recommended for species status of allopatric populations of thamnophilid antbirds and should provide a useful reference point for future considerations of species limits. C1 Smithsonian Inst, Div Birds, Museum Natl Hist Nat, Washington, DC 20560 USA. Louisiana State Univ, Museum Nat Sci, Baton Rouge, LA 70803 USA. RP Isler, ML (reprint author), Smithsonian Inst, Div Birds, Museum Natl Hist Nat, Washington, DC 20560 USA. NR 20 TC 39 Z9 46 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 JAN PY 1999 VL 116 IS 1 BP 83 EP 96 PG 14 WC Ornithology SC Zoology GA 160RJ UT WOS:000078244500009 ER PT J AU McCourt, RM Karol, KG Casanova, MT Feist, M AF McCourt, RM Karol, KG Casanova, MT Feist, M TI Monophyly of genera and species of characeae based on rbcL sequences, with special reference to Australian and European Lychnothamnus barbatus (Characeae : Charophyceae) SO AUSTRALIAN JOURNAL OF BOTANY LA English DT Article ID PHYLOGENY AB Sequences for the chloroplast-encoded large subunit of the Rubisco gene (rbcL) were used to rest the monophyly of multiple isolates within species, and multiple species within genera, of green algae in the Characeae (Class Charophyceae). Parsimony and maximum likelihood analyses supported the monophyly of genera and most species, with the exception of a paraphyletic assemblage comprising isolates of two 'species', dioecious Chara connivens Salzm, ex A.Br. and monoecious C. globularis Thuill., which together constitute a monophyletic group. The rbcL data support the independent evolution of either monoecious or dioecious sexual systems in the two connivens-globularis, clades. Comparisons of disjunct isolates of the monotypic Lychnothamnus barbatus (Meyen) Leohn. revealed nearly identical rbcL sequences in isolates from Croatia, Germany and Australia, although all three sequences were unique. The variation exhibited by these isolates was similar to variation between isolates within species of Chara and Lamprothamnium from different continents. The limited variation may be due to dispersal of thalli or oospores between continents; however, the rarity of known intercontinental transfers of Characeae in the last two centuries suggests that the Australian population is probably not an exotic from Europe. Lychnothamnus barbatus populations in Australia and elsewhere thus merit continued protected status. C1 Acad Nat Sci Philadelphia, Dept Bot, Philadelphia, PA 19103 USA. Smithsonian Inst, Natl Museum Nat Hist, Lab Mol Systemat, Washington, DC 20560 USA. Univ New England, Dept Bot, Armidale, NSW 2351, Australia. Univ Sci, Inst Sci Evolut, Lab Paleobot, F-34095 Montpellier, France. RP McCourt, RM (reprint author), Acad Nat Sci Philadelphia, Dept Bot, 19th & Pkwy, Philadelphia, PA 19103 USA. NR 27 TC 25 Z9 27 U1 0 U2 7 PU C S I R O PUBLISHING PI COLLINGWOOD PA 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA SN 0067-1924 J9 AUST J BOT JI Aust. J. Bot. PY 1999 VL 47 IS 3 BP 361 EP 369 DI 10.1071/BT97100 PG 9 WC Plant Sciences SC Plant Sciences GA 224LE UT WOS:000081899900009 ER PT J AU Holtum, JAM Winter, K AF Holtum, JAM Winter, K TI Degrees of crassulacean acid metabolism in tropical epiphytic and lithophytic ferns SO AUSTRALIAN JOURNAL OF PLANT PHYSIOLOGY LA English DT Article DE crassulacean acid metabolism; CAM; ferns; tropical epiphyte; lithophyte ID TALINUM PORTULACACEAE; VASCULAR EPIPHYTES; CO2; CAM; PHOTOINHIBITION; PILOSELLOIDES; ECOPHYSIOLOGY; EXCHANGE; LEAVES; PLANT AB Crassulacean acid metabolism (CAM) was observed in three species of tropical ferns, the epiphytes Microsorium punctatum and Polypodium crassifolium and the lithophyte Platycerium veitchii. Polypodium crassifolium and P. veitchii exhibited characteristics of weak CAM. Although no net nocturnal CO2 uptake was observed, the presence of CAM was inferred from nocturnal increases in titratable acidity of 4.7 and 4.1 mu equiv (g fr wt)(-1) respectively, a reduction in the rates of net CO2 evolution during the first half of the dark period, and the presence of a CAM-like decrease in net CO2 uptake during the early light period. In M. punctatum net CO2 uptake during the first half of the dark period was accompanied by an increase in titratable acidity of 39.2 mu equiv (g fr wt) -1 and a pronounced reduction in net CO2 uptake during the early light period. When water was withheld from P. crassifolium and M. punctatum, net CO2 uptake during the light was reduced markedly but there was no change in the extent or patterns of CO2 exchange in the dark. As a consequence, the proportion of carbon gained due to CO2 fixation in the dark increased from 2.8 and 10% to 63.5 and 49.3%, respectively (100% being net CO2 uptake during the light plus the estimated CO2 uptake during the dark). After 9 days without added water, dark CO2 uptake was responsible for the maintenance of a net 24 h carbon gain in P. crassifolium. Platycerium veitchii, P. crassifolium and M. punctatum exhibited carbon isotope ratios of between -25.9 and -22.6 parts per thousand indicating that carbon isotope ratios may not, by themselves, be sufficient for the identification of weak CAM. We suggest that CAM may be more prevalent in tropical epiphytic and lithophytic ferns than currently envisaged. C1 Smithsonian Trop Res Inst, Balboa, Panama. James Cook Univ N Queensland, Sch Trop Biol, Dept Trop Plant Sci, Townsville, Qld 4811, Australia. RP Holtum, JAM (reprint author), Smithsonian Trop Res Inst, POB 2072, Balboa, Panama. EM joseph.holtum@jcu.edu.au RI Holtum, Joseph/B-3063-2012 OI Holtum, Joseph/0000-0001-6568-8019 NR 33 TC 40 Z9 45 U1 7 U2 15 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 1999 VL 26 IS 8 BP 749 EP 757 PG 9 WC Plant Sciences SC Plant Sciences GA 261DN UT WOS:000083993500004 ER PT B AU Olson, SL AF Olson, SL BE Olson, SL TI The Anseriform relationships of Anatalavis Olson and Parris (Anseranatidae), with a new species from the lower Eocene London Clay SO AVIAN PALEONTOLOGY AT THE CLOSE OF THE 20TH CENTURY SE SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY-SERIES LA English DT Proceedings Paper CT 4th International Meeting of the Society-of-Avian-Paleontology-and-Evolution CY JUN 04-07, 1996 CL SMITHSONIAN INST, WASHINGTON, DC SP Natl Museum Nat Hist, Smithsonian Inst, Off Director, 150th Anniversary Program Comm HO SMITHSONIAN INST ID BIRDS; AVES AB An associated partial skeleton, including the skull but lacking legs, from the lower Eocene London Clay of Essex, England, possesses derived characters of the coracoid and furcula that show it to belong to the Anseranatidae, which previously had no fossil record. Except for its much larger size, the humerus of this specimen is identical to that of Anatalavis rex (Shufeldt) from the late Cretaceous or early Paleocene of New Jersey. The Eocene specimen is described as a new species, Anatalavis oxfordi, and the genus Anatalavis is transferred from the form-family Graculavidae to a new subfamily Anatalavinae, of the Anseranatidae. Anatalavis is characterized by a very broad duck-like bill, a proportionately very short and robust humerus, and an anterior portion of the pelvis resembling that of ibises and other wading birds more than that of any known anseriform. Other features of its osteology are unique within the order. C1 Smithsonian Inst, Museum Natl Hist Nat, Dept Vertebrate Zool, Washington, DC 20560 USA. RP Olson, SL (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Vertebrate Zool, Washington, DC 20560 USA. NR 22 TC 4 Z9 4 U1 1 U2 2 PU SMITHSONIAN INST PRESS PI WASHINGTON PA 900 JEFFERSON DRIVE SW, WASHINGTON, DC 20560 USA J9 SM C PALEOB PY 1999 IS 89 BP 231 EP 243 PG 13 WC Ornithology; Paleontology SC Zoology; Paleontology GA BP56S UT WOS:000085518700018 ER PT J AU Cocroft, RB AF Cocroft, RB TI Offspring-parent communication in a subsocial treehopper (Hemiptera : Membracidae : Umbonia crassicornis) SO BEHAVIOUR LA English DT Article ID VIBRATIONAL SIGNALS; MATING-BEHAVIOR; HOMOPTERA; CONFLICT; EVOLUTION; INSECTS; SPECIATION; PHEROMONES; SELECTION; DEFENSE AB Parental care of post-hatching offspring is widespread in insects, but the role of communication in parent-offspring interactions remains largely unknown. I have found that, in the subsocial treehopper Umbonia crassicornis, aggregated nymphal offspring produce substrate-borne, vibrational signals in synchronized bursts that elicit the mother's antipredator behavior. In this study I describe the signals used by nymphs and explore their role in mother-offspring interactions and within-brood communication. Nymphs were stimulated to signal in the laboratory in response to light contact, simulating the approach of a predator. Signals of nymphs at the site of disturbance triggered a rapid wave of sigaling by many individuals within the aggregation. This coordinated signaling was associated with the mother's defensive behavior. Signaling was limited to the vibrational channel: when transmission of vibrations was blocked between signaling nymphs and the mother, the mothers' response was abolished. Nymphs signaled not only in response to contact, but also in response to playback of signals from their siblings. Nymphs in otherwise undisturbed aggregations signaled only in response to signals coordinated into synchronized, group displays, and not to signals in random temporal patterns. However, nymphal signaling thresholds were lowered after a recent experience of simulated predation. After a period in which nymphs were stimulated to signal (by light contact simulating a predator's approach), playback of one individual signal could trigger a coordinated burst within the aggregation. It remains unknown if coordination among siblings to produce synchronized, group signals is completely cooperative, or if siblings compete for the mother's proximity. But it is clear that a complex system of communication among siblings, and between siblings and their parent, is an important feature of maternal care in these subsocial insects. C1 Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. RP Cocroft, RB (reprint author), Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. NR 62 TC 33 Z9 33 U1 5 U2 8 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 1999 VL 136 BP 1 EP 21 PN 1 PG 21 WC Behavioral Sciences; Zoology SC Behavioral Sciences; Zoology GA 172NF UT WOS:000078930100001 ER PT J AU Wheeler, JW Ibrahim, SA Weldon, PJ AF Wheeler, JW Ibrahim, SA Weldon, PJ TI 2,3-Dihydrofarnesyl and citronellyl esters in the paracloacal gland secretions of the brown caiman (Caiman crocodilus fuscus) from Costa Rica SO BIOCHEMICAL SYSTEMATICS AND ECOLOGY LA English DT Article DE brown caiman; Caiman crocodilus fuscus; paracloacal glands; 2,3-dihydrofarnesol; 2,3-dihydrofarnesyl esters; citronellyl esters; lipid identifications ID ALLIGATOR ALLIGATOR-SINENSIS; LIPIDS; TRIGONATUS AB The paracloacal gland secretions of a male and a female brown caiman (Caiman crocodilus fuscus) from Costa Rica were analyzed by gas chromatography-mass spectrometry. 3,7,11-Trimethyldodeca-6,10-dien-1-ol (2,3-dihydrofarnesol) and 20 of its esters, with acid moieties ranging in carbon-chain length from two to 18, were observed in one or both sexes. Most of these compounds have not previously been described from a natural source. 3,7-Dimethyl-6-octen-1-yl (citronellyl) acetate, citronellyl butanoate, and citronellyl hexanoate were observed in the secretions of the female caiman. Squalene was observed in both sexes. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Howard Univ, Dept Chem, Washington, DC 20059 USA. Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Wheeler, JW (reprint author), Howard Univ, Dept Chem, Washington, DC 20059 USA. NR 11 TC 7 Z9 7 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0305-1978 J9 BIOCHEM SYST ECOL JI Biochem. Syst. Ecol. PD JAN PY 1999 VL 27 IS 1 BP 27 EP 32 DI 10.1016/S0305-1978(98)00054-4 PG 6 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 145YU UT WOS:000077400600003 ER PT B AU Allen, ME Chen, TC Holick, MF Merkel, E AF Allen, ME Chen, TC Holick, MF Merkel, E BE Holick, MF Jung, EG TI Evaluation of vitamin D status in the green iguana (Iguana iguana): Oral administration vs UVB exposure SO BIOLOGIC EFFECTS OF LIGHT 1998 LA English DT Proceedings Paper CT 5th International Arnold Rikli Symposium on the Biologic Effects of Light CY NOV 01-03, 1998 CL BASEL, SWITZERLAND C1 Smithsonian Inst, Natl Zool Pk, Dept Nutr Resources, Washington, DC 20008 USA. RP Allen, ME (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Nutr Resources, Washington, DC 20008 USA. NR 3 TC 7 Z9 7 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-8550-0 PY 1999 BP 99 EP 101 PG 3 WC Biology; Dermatology; Physiology SC Life Sciences & Biomedicine - Other Topics; Dermatology; Physiology GA BP14K UT WOS:000084221800017 ER PT J AU Pelican, KM Pukazhenthi, BS Wildt, DE Howard, JG AF Pelican, KM Pukazhenthi, BS Wildt, DE Howard, JG TI Discontinuous colloidal gradient centrifugation reduces sperm flagellum abnormalities but disrupts acrosomes in cat ejaculates. SO BIOLOGY OF REPRODUCTION LA English DT Meeting Abstract C1 Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA USA. NR 0 TC 0 Z9 0 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 1999 VL 60 SU 1 MA 136 BP 136 EP 136 PG 1 WC Reproductive Biology SC Reproductive Biology GA 211CA UT WOS:000081141300205 ER PT J AU Spindler, RE Wildt, DE AF Spindler, RE Wildt, DE TI Cat oocyte metabolism indicates fertilization and developmental potential. SO BIOLOGY OF REPRODUCTION LA English DT Meeting Abstract C1 Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA USA. NR 0 TC 0 Z9 0 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 1999 VL 60 SU 1 MA 269 BP 177 EP 177 PG 1 WC Reproductive Biology SC Reproductive Biology GA 211CA UT WOS:000081141300333 ER PT J AU Brown, JL AF Brown, JL TI Problems with ovarian dysfunction in elephants. 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 1999 VL 60 SU 1 MA 460 BP 236 EP 236 PG 1 WC Reproductive Biology SC Reproductive Biology GA 211CA UT WOS:000081141300524 ER PT J AU Penfold, LM Citino, SB Monfort, SL Wildt, DE AF Penfold, LM Citino, SB Monfort, SL Wildt, DE TI Investigating age and seasonality as potential contributors to pleiomorphic spermatozoa in gerenuk. SO BIOLOGY OF REPRODUCTION LA English DT Meeting Abstract C1 White Oak Conservat Ctr, Yulee, FL USA. Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA USA. NR 0 TC 0 Z9 0 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 1999 VL 60 SU 1 MA 535 BP 259 EP 259 PG 1 WC Reproductive Biology SC Reproductive Biology GA 211CA UT WOS:000081141300595 ER PT B AU Quinn, J AF Quinn, J CA Whipple Collaboration BE Takalo, LO Sillanpaa, A TI TeV gamma-ray variability of Markarian 501 SO BL LAC PHENOMENON SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Meeting on BL Lac Phenomenon CY JUN 22-26, 1998 CL TURKU, FINLAND AB Since its discovery as a source of TeV gamma-rays in 1995, Markarian 501 has been routinely monitored with the Whipple Collaboration 10 m atmospheric Cerenkov imaging; telescope. Here we present the results of analysis of our 1995 - 1998 data set for flux variability on several timescales. Significant variability was detected on timescales ranging from hours to years, with a flux doubling time as short as two hours observed on one occasion (MJD 50607). We also present the energy spectrum of Markarian 501 in range 250 GeV to 10 TeV and compare it to that of Markarian 421. C1 Smithsonian Astrophys Observ, Whipple Observ, Amado, AZ 85645 USA. RP Quinn, J (reprint author), Smithsonian Astrophys Observ, Whipple Observ, Amado, AZ 85645 USA. NR 6 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 1-886733-79-1 J9 ASTR SOC P PY 1999 VL 159 BP 239 EP 242 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BM90V UT WOS:000080089400061 ER PT J AU Gacia, E AF Gacia, E TI Leaf dynamics and shoot production of the seagrass Thalassia testudinum in the Indian River Lagoon (Florida) SO BOTANICA MARINA LA English DT Article ID SYRINGODIUM-FILIFORME KUTZ; HALODULE-WRIGHTII; TURTLE GRASS; GROWTH; BIOMASS; BIODIVERSITY; COMMUNITIES; DIVERSITY; ABUNDANCE; KONIG AB Leaf growth, biomass and production of Thalassia testudinum were measured from January 1995 to March 1996, for a monospecific population in the Indian River Lagoon (IRL; Florida). Seasonal pattern of shoot biomass was characterized by low values during late winter (minimum of 0.17 g dw shoot(-1) in March) and high values in mid-summer (July; 0.32 g dw shoot(-1)). Production of new leaves followed a pattern similar to shoot biomass, although maximum production of leaves occurred slightly earlier (late May; 0.07 leaves shoot(-1) day(-1)) than did maximum leaf elongation and biomass accumulation (July; 3.63 cm shoot(-1) day(-1) and 0.007 g dw shoot(-1) day(-1)). Shoot densities (m(-2)) were low by the end of winter (390 +/- 50.7 SE) and high in late summer (840 +/- 201 SE), thus resulting in a measured standing stock variation between 197 and 328 g dw m(-2). Annual shoot production amounted to 890 g dw m(-2) and biomass turnover was 3.6. Compilation of data from the literature with results from this study showed T. testudinum leaf production was related to standing stock (p < 0.0001) by a factor of 0.016. Average daily production vs, biomass (P/B) slightly increased at lower latitudes. However, latitude only explained 34 % of the variation in P/B, other ecological factors (e. g, light or nutrient limitation) may play a major role in determining biomass and primary production for this species. Based on latitude alone, maximum potential production for Thalassia testudinum in the IRL (close to the northern limit of distribution for this species) would be up to 30 % lower than the values expected at the southern limit of distribution of this species. C1 Smithsonian Marine Stn Link Port, Ft Pierce, FL 34946 USA. RP Gacia, E (reprint author), CSIC, Ctr Estudis Acancats Blances, Ctra Santa Barbra S-N, E-17300 Blanes, Spain. RI Gacia, Esperanca/J-9238-2012 OI Gacia, Esperanca/0000-0002-7687-7437 NR 41 TC 4 Z9 4 U1 0 U2 3 PU WALTER DE GRUYTER & CO PI BERLIN PA GENTHINER STRASSE 13, D-10785 BERLIN, GERMANY SN 0006-8055 J9 BOT MAR JI Bot. Marina PD JAN PY 1999 VL 42 IS 1 BP 97 EP 102 DI 10.1515/BOT.1999.012 PG 6 WC Plant Sciences; Marine & Freshwater Biology SC Plant Sciences; Marine & Freshwater Biology GA 169MT UT WOS:000078753200012 ER PT J AU Wagner, WL Fletcher, RA Shannon, RK AF Wagner, WL Fletcher, RA Shannon, RK TI Another look at Hymenoxys subgenus Plummera (Asteraceae : Heliantheae : Gaillardiinae) from Arizona and New Mexico SO BRITTONIA LA English DT Article DE Asteraceae; Compositae; Heliantheae; Gaillardiinae; Hymenoxys; Plummera; Arizona; New Mexico AB Wagner, W. L. (Department of Botany, MRC 166, National Museum of Natural History, Smithsonian Institution, Washington, DC 20560, U.S.A.), R. A. Fletcher (U.S. Forest Service, 517 Gold Ave., SW, Albuquerque, NM 87102, U.S.A.) & R. K. Shannon (Department of Botany, MRC-166, National Museum of Natural History, Smithsonian Institution, Washington, DC 20560, U.S.A.). Another look at Hymenoxys subgenus Plummera (Asteraceae: Heliantheae: Gaillardiinae) from Arizona and New Mexico. Brittonia 51. 79-86. 1999. -The recent merger of Plummera into Hymenoxys is followed here. The two previously recognized species of Plummera are here treated as a single polymorphic species of Hymenoxys, H. ambigens, consisting of three varieties: var. ambigens from the Mescal, Santa Teresa, and Pinaleno Mountains of southeastern Arizona; var. floribunda from the Chiricahua, Dos Cabezas, Dragoon, Little Dragoon, and Mule Mountains of southeastern Arizona; and var, neomexicana described here from the Animas and Peloncillo Mountains of southwestern New Mexico. C1 Natl Museum Nat Hist, Smithsonian Inst, Dept Bot, Washington, DC 20560 USA. RP Wagner, WL (reprint author), Natl Museum Nat Hist, Smithsonian Inst, Dept Bot, MRC 166, Washington, DC 20560 USA. NR 10 TC 0 Z9 1 U1 2 U2 3 PU NEW YORK BOTANICAL GARDEN PI BRONX PA PUBLICATIONS DEPT, BRONX, NY 10458 USA SN 0007-196X J9 BRITTONIA JI Brittonia PD JAN-MAR PY 1999 VL 51 IS 1 BP 79 EP 86 DI 10.2307/2666562 PG 8 WC Plant Sciences SC Plant Sciences GA 186JT UT WOS:000079726300010 ER PT B AU Reid, MJ Readhead, ACS Vermeulen, RC Treuhaft, RN AF Reid, MJ Readhead, ACS Vermeulen, RC Treuhaft, RN BE Falcke, H Cotera, A Duschl, WJ Melia, F Rieke, MJ TI The proper motion and mass of Sgr A* SO CENTRAL PARSECS OF THE GALAXY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Galactic Center Workshop on the Central Parsecs of the Galaxy CY SEP 07-11, 1998 CL TUCSON, AZ SP Univ Heidelberg, Univ Arizona, Phys Dept, NICMOS, Steward Observ, Max Planck Inst Radioastronomie, Bonn, Inst Theoret Astrophys, Heidelberg ID GALAXY AB The apparent proper motion of Sgr A*, relative to extragalactic sources, is consistent with that expected from the Sun orbiting the center of the Galaxy. Using the VLBA we obtain a lower limit for the peculiar motion of Sgr A* of about 20 km s(-1), implying a lower limit for mass of Sgr A* of similar to 10(3) M-.. This rules out the possibility that Sgr A* is a stellar system, such as a contact binary, containing similar to 10 M-. and radiating near its Eddington luminosity, A mass of more than similar to 10(3) Mo and a luminosity less than or similar to 10(5) L-. indicates that Sgr A* is radiating at less than or similar to 0.1% of its Eddington limit. All observations are consistent with Sgr A* being a super-massive black hole. Since the lower limit for the mass of Sgr A* is only about 0.1% of the gravitational mass inferred from the stellar motions, one cannot claim from our observations done that even a significant fraction of the dark mass must be in Sgr A*. However, alternative models of dark matter distributions are severely restricted by these observations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Reid, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NR 15 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 1-58381-012-9 J9 ASTR SOC P PY 1999 VL 186 BP 24 EP 31 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP16P UT WOS:000084260600003 ER PT B AU Zhao, JH Goss, WM AF Zhao, JH Goss, WM BE Falcke, H Cotera, A Duschl, WJ Melia, F Rieke, MJ TI Proper motions and structure of the radio components near Sgr A*: Evidence for ionized gas palling into the massive black hole at the galactic center SO CENTRAL PARSECS OF THE GALAXY SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT Galactic Center Workshop on the Central Parsecs of the Galaxy CY SEP 07-11, 1998 CL TUCSON, AZ SP Univ Heidelberg, Univ Arizona, Phys Dept, NICMOS, Steward Observ, Max Planck Inst Radioastronomie, Bonn, Inst Theoret Astrophys, Heidelberg ID GALAXY; WEST AB Proper motions and radio structures of the HII components near Sgr A* have been determined based on high resolution (0.1 ") observations at 13 and 7 mm during the past 7 years (1991-1998). Proper motions up to 30 mas yr(-1) (or 1200 km s(-1)) have been observed for a number of prominent features. These proper motions, measured from compact HII components, can be explained by motions of a clumpy HII gas accelerated by either strong winds and outflows or explosive events at the Galactic Center. Large pattern speeds due to wave or shock motions in the circumnuclear medium at the Galactic Center can also be responsible for some of the observed proper motions. In addition, the HII components near Sgr A* (within the central 2.5 " or 0.1 pc) show filamentary structures suggesting that the HII components are tidally disrupted by tides due to the concentrated mass at the Galactic Center. Based on the proper motion measurements, we also infer that the Minicavity is a transient phenomena (< 500 years old), created by the interactions between the orbiting ionized streamer and the fast moving materials at the Galactic Center. The proper motion of the Tip, NE of the Minicavity, suggests that a portion of the orbiting ionized gas components will lose angular momenta and move towards Sgr A* as a result of these interactions. High precision measurements of the proper motions for the emitting HII components can be used to track the motions of the accreting gas in proximity to the super massive black hole associated with Sgr A*. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Zhao, JH (reprint author), Harvard Smithsonian Ctr Astrophys, MS 78, Cambridge, MA 02138 USA. NR 15 TC 10 Z9 10 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-012-9 J9 ASTR SOC P PY 1999 VL 186 BP 224 EP + PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP16P UT WOS:000084260600024 ER PT B AU Bagla, JS AF Bagla, JS BE Mazure, A LeFevre, O LeBrun, V TI Clustering of high redshift galaxies SO CLUSTERING AT HIGH REDSHIFT SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Meeting on Clustering at High Redshift CY JUN 29-JUL 02, 1999 CL MARSEILLE, FRANCE ID Z-SIMILAR-TO-3; EVOLUTION AB Discovery of Lyman break galaxies and their observed clustering led to a better understanding about how galaxies cluster. One fallout of this is the degeneracy of different models of structure formation, they all satisfy the constraints set by the number density and the observed correlation function. I suggest that this degeneracy can be broken by measuring the third moment of clustering of Lyman break galaxies. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Bagla, JS (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS-51, Cambridge, MA 02138 USA. NR 12 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 1-58381-027-7 J9 ASTR SOC P PY 1999 VL 200 BP 178 EP 181 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ39K UT WOS:000088232100028 ER PT J AU Pravia, M Fortunato, E Weinstein, Y Price, MD Teklemariam, G Nelson, RJ Sharf, Y Somaroo, S Tseng, CH Havel, TF Cory, DG AF Pravia, M Fortunato, E Weinstein, Y Price, MD Teklemariam, G Nelson, RJ Sharf, Y Somaroo, S Tseng, CH Havel, TF Cory, DG TI Observations of quantum dynamics by solution-state NMR spectroscopy SO CONCEPTS IN MAGNETIC RESONANCE LA English DT Article DE pseudo-pure states; ensemble quantum computing; quantum information processing; quantum statistical mechanics ID IMPLEMENTATION; ALGORITHM; COMPUTATION; COMPUTER AB NMR is emerging as a valuable testbed for the investigation of foundational questions in quantum mechanics. The present article outlines the preparation of a class of mixed states, called pseudo-pure states. that emulate pure quantum states in highly mixed solution-state NMR samples. It also describes the NMR observation of spinor behavior in spin 1/2 nuclei, the simulation of wave function collapse using a magnetic field gradient, the creation of entangled (i.e., Bell) pseudo-pure states, and a brief discussion of quantum computing logic gates including the Quantum Fourier Transform. These experiments show that solution-state NMR can be used to demonstrate quantum dynamics at a level suitable for laboratory exercises. (C) 1999 John Wiley & Sons. Inc. C1 MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. MIT, Dept Mech Engn, Cambridge, MA 02139 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. Harvard Univ, Sch Med, BCMP, Boston, MA 02115 USA. Harvard Smithsonian, Ctr Astrophys, Cambridge, MA 02138 USA. RP Cory, DG (reprint author), MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. RI Weinstein, Yaakov/A-3513-2013 NR 25 TC 21 Z9 22 U1 1 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1043-7347 J9 CONCEPT MAGNETIC RES JI Concepts Magn. Resonance PY 1999 VL 11 IS 4 BP 225 EP 238 DI 10.1002/(SICI)1099-0534(1999)11:4<225::AID-CMR3>3.3.CO;2-5 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical; Radiology, Nuclear Medicine & Medical Imaging; Spectroscopy SC Chemistry; Physics; Radiology, Nuclear Medicine & Medical Imaging; Spectroscopy GA 209VM UT WOS:000081069800003 ER PT B AU Ryan, MJ Rand, AS AF Ryan, MJ Rand, AS BE Hauser, MD Konishi, M TI Phylogenetic inference and the evolution of communication in tungara frogs SO DESIGN OF ANIMAL COMMUNICATION LA English DT Proceedings Paper CT Symposium on the Design of Animal Communication in Honor of Peter Marler CY MAR 22-23, 1997 CL UNIV CALIF DAVIS, DAVIS, CA HO UNIV CALIF DAVIS ID PUSTULOSUS SPECIES GROUP; PHYSALAEMUS-PUSTULOSUS; SEXUAL SELECTION; SENSORY EXPLOITATION; NEOTROPICAL FROG; TRACHOPS-CIRRHOSUS; MATING PREFERENCES; FEMALE PREFERENCE; PREEXISTING BIAS; MATE RECOGNITION C1 Smithsonian Trop Res Inst, Washington, DC 20560 USA. RP Ryan, MJ (reprint author), Smithsonian Trop Res Inst, Washington, DC 20560 USA. NR 53 TC 11 Z9 13 U1 1 U2 2 PU M I T PRESS PI CAMBRIDGE PA FIVE CAMBRIDGE CENTER, CAMBRIDGE, MA 02142 USA BN 0-262-08277-2 PY 1999 BP 535 EP 557 PG 23 WC Behavioral Sciences; Neurosciences SC Behavioral Sciences; Neurosciences & Neurology GA BP71F UT WOS:000085943200022 ER PT J AU Lovell, AJ Schloerb, FP Bergin, EA Dickens, JE Devries, CH Senay, MC Irvine, WM AF Lovell, AJ Schloerb, FP Bergin, EA Dickens, JE Devries, CH Senay, MC Irvine, WM TI HCO+ in the coma of comet Hale-Bopp SO EARTH MOON AND PLANETS LA English DT Article; Proceedings Paper CT 1st International Conference on Comet Hale-Bopp CY FEB 02-05, 1998 CL TENERIFE, SPAIN DE comets; HCO; chemistry; plasmas AB Maps of comet C/1995 O1 (Hale-Bopp) in the millimeter-wave emission of the ion HCO+ revealed a local minimum near the nucleus position, with a maximum about 100,000 km in the antisolar direction. These observed features of the HCO+ emission require a low abundance of HCO+ due to enhanced destruction in the inner coma of the comet, within a region of low electron temperature (T-e). To set constraints on the formation of HCO+ in the coma, as well as the location and magnitude of the transition to higher T-e, the data are compared with the results of ion-molecule chemistry models. C1 Univ Massachusetts, Five Coll Radio Astron Observ, Amherst, MA 01003 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Univ Massachusetts, Five Coll Radio Astron Observ, Amherst, MA 01003 USA. NR 20 TC 6 Z9 6 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-9295 EI 1573-0794 J9 EARTH MOON PLANETS JI Earth Moon Planets PY 1999 VL 77 IS 3 BP 253 EP 258 PG 6 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Geology GA 249RQ UT WOS:000083346400017 ER PT J AU Purata, SE Greenberg, R Barrientos, V Lopez-Portillo, J AF Purata, SE Greenberg, R Barrientos, V Lopez-Portillo, J TI Economic potential of the Huizache, Acacia pennatula (Mimosoideae) in central Veracruz, Mexico SO ECONOMIC BOTANY LA English DT Article DE Acacia pods; livestock fodder; silvopastoral system ID SAVANNA VERTEBRATES; BRUCHID BEETLES; HISTORY; AMERICA; WORLD AB Acacia pennatula is a native tree found commonly on cattle pastures and other disturbed sites in the mid-elevation zone of Veracruz, Mexico. The pods are a favorite food source for free ranging cattle. Pod collection and production has been commercialized at a small scale, The results of this study strongly suggest that the management of acacia trees for pod production has the potential for providing an environmentally sound, locally derived food source for cattle while maintaining tree cover on pasture lands. Soil type has a strong influence on stand structure and pod production; the largest pod crops with the largest and most nutritious pods are found on Andosols and Acrisols, as opposed to the unproductive Regosols. We suggest thar the current system could be expanded by promotion and marketing of the pods and improved management of the acacia stands. C1 Inst Ecol, Xalapa 91000, Ver, Mexico. Smithsonian Inst, Natl Zool Pk, Smithsonian Migratory Bird Ctr, Washington, DC 20008 USA. RP Purata, SE (reprint author), Inst Ecol, AC Apdo Postal 63, Xalapa 91000, Ver, Mexico. RI Lopez Portillo, Jorge/L-2492-2014 OI Lopez Portillo, Jorge/0000-0002-6827-3297 NR 46 TC 8 Z9 9 U1 0 U2 4 PU NEW YORK BOTANICAL GARDEN PI BRONX PA PUBLICATIONS DEPT, BRONX, NY 10458 USA SN 0013-0001 J9 ECON BOT JI Econ. Bot. PD JAN-MAR PY 1999 VL 53 IS 1 BP 15 EP 29 DI 10.1007/BF02860787 PG 15 WC Plant Sciences SC Plant Sciences GA 187RH UT WOS:000079800200002 ER PT J AU Basset, Y AF Basset, Y TI Diversity and abundance of insect herbivores collected on Castanopsis acuminatissima (Fagaceae) in New Guinea: Relationships with leaf production and surrounding vegetation SO EUROPEAN JOURNAL OF ENTOMOLOGY LA English DT Article DE Castanopsis; Coleoptera; host specificity; insect herbivores; Papua New Guinea; species richness ID PAPUA-NEW-GUINEA; RAIN-FOREST; TREE; PATTERNS; AUCHENORRHYNCHA; COMMUNITIES; ARBOREAL AB Insect herbivores were collected from Castanopsis acuminatissima (Fagaceae) at Wau, Papua New Guinea, by beating the foliage of 15 trees during four one-month sampling periods, each representing different leaf-flush events. The association of leaf-chewing beetles with C. acuminatissima was verified with feeding trials. Of 59 species of leaf-chewing beetles that were collected, 36 species could be used in feeding trials. Only 9 of these species fed on C. acuminatissima. A further 27 beetle species were tested in feeding trials but did not feed. Of these, 7 were specialists feeding on other tree species within the surrounding vegetation. Most beetle species collected from C, acuminatissima foliage were probably transient species, dispersing from other tree species. Path analyses showed that herbivore abundance during a particular sampling period was significantly influenced by rainfall, leaf flush of other conspecific trees and air temperature, but not so by the species richness of surrounding vegetation, number of surrounding conspecific trees and size (DBH) of trees sampled. The species richness of leaf-chewing beetles collected on particular study trees depended on that of the surrounding vegetation, thus supporting the hypothesis that most beetle species collected were transient. The abundance of insect herbivores on particular C. acuminatissima trees probably depends on a balance between the leaf flush of conspecific trees and that of the particular tree sampled. The results also emphasize the need to remove transient species in analyses of insect faunas of tropical trees, at the risk of analyzing species richness patterns derived from loosely defined "assemblages" of species. C1 Smithsonian Trop Res Inst, Balboa, Ancon, Panama. RP Basset, Y (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Ancon, Panama. RI Basset, Yves/B-6642-2014 NR 40 TC 16 Z9 22 U1 0 U2 7 PU CZECH ACAD SCI, INST ENTOMOLOGY PI CESKE BUDEJOVICE PA BRANISOVSKA 31, CESKE BUDEJOVICE 370 05, CZECH REPUBLIC SN 1210-5759 J9 EUR J ENTOMOL JI Eur. J. Entomol. PY 1999 VL 96 IS 4 BP 381 EP 391 PG 11 WC Entomology SC Entomology GA 277DU UT WOS:000084918100007 ER PT S AU Tananbaum, H White, NE Bookbinder, JA Marshall, FE Cordova, FA AF Tananbaum, H White, NE Bookbinder, JA Marshall, FE Cordova, FA BE Siegmund, OH Flanagan, KA TI The Constellation X-ray mission: Implementation concept and science overview SO EUV, X-RAY, AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY X SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy X CY JUL 21-23, 1999 CL DENVER, CO SP SPIE DE X-rays; spectroscopy; Constellation-X; abundances AB The Constellation-X mission is a large collecting area X-ray facility, emphasizing observations at high spectral resolution (E/Delta E similar to 300-3000) while covering a broad energy band(0.25-40 keV). By increasing the telescope aperture and utilizing efficient spectrometers the mission will achieve a factor of 100 increased sensitivity over current high resolution ii-ray spectroscopy missions. The use of focussing optics across the 10-40 keV band will provide a similar factor of 100 increased sensitivity in this band. Key technologies under development for the mission include lightweight high throughput ii-ray optics, multilayer coatings to enhance the hard ii-ray performance of ii-ray optics, micro-calorimeter spectrometer arrays with 2 eV resolution,low power and low weight CCD arrays, lightweight gratings and hard ii-ray detectors. When observations commence towards the end of the next decade, Constellation-X will address many pressing questions concerning the extremes of gravity and the evolution of the Universe. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Tananbaum, H (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 8 TC 21 Z9 21 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3251-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3765 BP 62 EP 72 DI 10.1117/12.366555 PG 11 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BP12E UT WOS:000084180500007 ER PT S AU Bloser, PF Grindlay, JE Narita, T Jenkins, JA AF Bloser, PF Grindlay, JE Narita, T Jenkins, JA BE Siegmund, OH Flanagan, KA TI Design and testing of a prototype pixellated CZT detector and shield for hard X-ray astronomy SO EUV, X-RAY, AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY X SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy X CY JUL 21-23, 1999 CL DENVER, CO SP SPIE DE CZT; background; shielding; balloon flights; hard X-ray astronomy; instrumentation AB We report on the design and laboratory testing of a prototype imaging CZT detector intended for balloon flight testing in April 2000. The detector tests several key techniques needed for the construction of large-area CZT arrays, as required for proposed hard X-ray astronomy missions. Two 10 mm x 10 mm x 5 mm CZT detectors, each with a 4 x 4 array of 1.9 mm pixels on a 2.5 mm pitch, will be mounted in a "flip-chip" fashion on a printed circuit board carrier card; the detectors Will be placed 0.3 mm apart in a tiled configuration such that the pixel pitch is preserved across both crystals. One detector is eV Products high-pressure Bridgman CZT, and the other is IMARAD horizontal Bridgman material, Both detectors are re;ld out by a 32-channel VA-TA ASIC controlled by a PC/104 single-board computer. A passive shield/collimator surrounded by plastic scintillator surrounds the detectors on five sides and provides a similar to 45 degrees field of view. The background spectrum recorded by this instrument will be compared to that measured by a single-element CZT detector (10 mm x 10 mm x 2 mm high-pressure Bridgman material from eV Products) fitted with the same passive/plastic collimator but including an active EGO shield to the rear. This detector has been previously flown by us completely shielded by a passive cover. We describe preliminary laboratory results for the various systems, discuss initial background simulations, and describe our plans for balloon flight tests. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Bloser, PF (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 13 TC 4 Z9 4 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3251-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3765 BP 388 EP 396 DI 10.1117/12.366519 PG 9 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BP12E UT WOS:000084180500038 ER PT S AU Kraft, RP Kenter, AT Murray, SS Gomes, JJ Johnston, EA AF Kraft, RP Kenter, AT Murray, SS Gomes, JJ Johnston, EA BE Siegmund, OH Flanagan, KA TI Design and testing of a low-cost X-ray CCD camera for the HRC program and beyond SO EUV, X-RAY, AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY X SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy X CY JUL 21-23, 1999 CL DENVER, CO SP SPIE DE X-rays; charge-coupled devices; X-ray detectors; X-ray spectroscopy AB We have designed, built, and tested a low cost, flexible X-ray CCD camera for laboratory use to assist with the calibration of the Chandra X-ray Observatory High Resolution Camera (HRC). This CCD camera design will also serve as a prototype for future flight opportunities. In this paper, we describe the design and performance of this camera, and present some sample data. For initial testing, we have purchased a commercially available EEV 30-11 CCD, but the camera can be modified to accommodate virtually any device in a minimal amount of time. We have achieved a readnoise of 3.5 electrons, and an energy resolution of 135 eV (FWHM) at; Mn K-alpha, with the EEV 30-11 device. This camera will be used extensively in the near future for HRC related calibrations. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Kraft, RP (reprint author), Smithsonian Astrophys Observ, 60 Garden St,MS-31, Cambridge, MA 02138 USA. NR 5 TC 0 Z9 0 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 0-8194-3251-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3765 BP 552 EP 563 DI 10.1117/12.366513 PG 12 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BP12E UT WOS:000084180500054 ER PT S AU Serej, S Kellogg, E Edgar, R Scholze, F Ulm, G AF Serej, S Kellogg, E Edgar, R Scholze, F Ulm, G BE Siegmund, OH Flanagan, KA TI Absolute calibration of the Chandra X-ray Observatory: transfer standard solid state detectors SO EUV, X-RAY, AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY X SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy X CY JUL 21-23, 1999 CL DENVER, CO SP SPIE DE Chandra; AXAF; detector calibration; detector response function; solid state detectors ID PTB AB In order to achieve as close as possible to the ground calibration goal of approximate to 1-2% for the Chandra X-ray Observatory (formerly AXAF), two high purity solid state detectors (SSD's) were used as transfer standards for measuring absolute x-ray flux. The calibration of these SSD's are based on the analysis of data obtained on various monochromatic and undispersed synchrotron beamlines at the BESSY electron storage ring in Berlin, Germany. Here we report on our updated analysis for determining the detector response function in the energy range 2.1-5.9 keV and on our recently completed analysis of the response function and detection efficiency measurements in the energy range 0.4-1.7 keV. The response function model used for spectral analysis of the data is based on the HYPERMET function, which is included in JMKmod within the XSPEC package. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Kellogg, E (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. RI Ulm, Gerhard/D-4798-2009 NR 10 TC 1 Z9 1 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 0-8194-3251-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3765 BP 777 EP 788 DI 10.1117/12.366563 PG 12 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BP12E UT WOS:000084180500077 ER PT J AU Wood, B Collard, M AF Wood, B Collard, M TI The changing face of genus Homo SO EVOLUTIONARY ANTHROPOLOGY LA English DT Review ID EARLY HOMINID PHYLOGENY; FOSSIL EVIDENCE; OLDUVAI-GORGE; TOOL BEHAVIOR; SOUTH-AFRICA; FUNCTIONAL-MORPHOLOGY; MIDDLE PLEISTOCENE; HUMAN-EVOLUTION; OLDOWAN TOOLS; LAKE TURKANA AB Since its introduction in the 18th century, the genus Homo has undergone a number of reinterpretations, all of which have served to make it a more inclusive taxon. In this paper, we trace this trend towards greater inclusiveness, and explain how it has affected the way Homo is defined. We then demonstrate that the current criteria for identifying species of Homo are difficult, if not impossible, to operate using paleoanthropological evidence. We discuss alternative, verifiable, criteria, and show that when these new criteria are applied to Homo, two species, Homo habilis and Homo rudolfensis, fail to meet them. We contend that the lowest boundary of Homo should be redrawn so that the earliest species in the genus is Homo ergaster, or early African Homo erectus. The appearance of this species at around 1.9 Myr appears to mark a distinct shift in hominin adaptive strategy involving morphological and behavioral innovations. C1 George Washington Univ, Dept Anthropol, Washington, DC 20052 USA. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. UCL, Dept Anthropol, London WC1E 6BT, England. RP Wood, B (reprint author), George Washington Univ, Dept Anthropol, 2110 G St NW, Washington, DC 20052 USA. EM bwood@gwu.edu; m.collard@ucl.ac.uk NR 135 TC 60 Z9 63 U1 23 U2 105 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1060-1538 J9 EVOL ANTHROPOL JI Evol. Anthropol. PY 1999 VL 8 IS 6 BP 195 EP 207 DI 10.1002/(SICI)1520-6505(1999)8:6<195::AID-EVAN1>3.0.CO;2-2 PG 13 WC Anthropology SC Anthropology GA 270ZF UT WOS:000084566500001 ER PT B AU Romanowsky, AJ AF Romanowsky, AJ BE Merritt, D Sellwood, JA Valluri, M TI A global dynamical model of M87 SO GALAXY DYNAMICS: A RUTGERS SYMPOSIUM SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Rutgers Symposium on Galaxy Dynamics CY AUG 08-12, 1998 CL RUTGERS UNIV, PISCATAWAY, NJ SP Rutgers Univ HO RUTGERS UNIV ID GLOBULAR-CLUSTERS; GALAXIES; SYSTEM C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Romanowsky, AJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 11 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 1-58381-007-2 J9 ASTR SOC P PY 1999 VL 182 BP 158 EP 159 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN98P UT WOS:000083761200039 ER PT B AU Barton, EJ Bromley, BC Geller, MJ AF Barton, EJ Bromley, BC Geller, MJ BE Merritt, D Sellwood, JA Valluri, M TI Kinematic effects of tidal interaction on galaxy rotation curves SO GALAXY DYNAMICS: A RUTGERS SYMPOSIUM SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Rutgers Symposium on Galaxy Dynamics CY AUG 08-12, 1998 CL RUTGERS UNIV, PISCATAWAY, NJ SP Rutgers Univ HO RUTGERS UNIV ID TAILS C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Barton, EJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 10, Cambridge, MA 02138 USA. NR 3 TC 1 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-007-2 J9 ASTR SOC P PY 1999 VL 182 BP 459 EP 460 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN98P UT WOS:000083761200118 ER PT S AU Zhang, XL AF Zhang, XL BE Barnes, JE Sanders, DB TI Hubble sequence as a temporal evolution sequence SO GALAXY INTERACTIONS AT LOW AND HIGH REDSHIFT SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 186th Symposium of the International-Astronomical-Union on Galaxy Interaction at Low and high Redshifts CY AUG 26-30, 1997 CL KYOTO, JAPAN SP Int Astron Union C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Zhang, XL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 78, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0074-1809 BN 0-7923-5832-5 J9 IAU SYMP PY 1999 IS 186 BP 491 EP 491 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ09W UT WOS:000087175400143 ER PT B AU Kolman, CJ AF Kolman, CJ BE Papiha, SS Deka, R Chakraborty, R TI Molecular anthropology - Progress and perspectives on ancient DNA technology SO GENOMIC DIVERSITY: APPLICATIONS IN HUMAN POPULATION GENETICS LA English DT Proceedings Paper CT Symposium on Molecular Anthropology in the 21st Century held at the 14th International Congress of the Association-of-Anthropological-and-Ethnological-Sciences CY JUL 26-AUG 01, 1998 CL WILLIAMSBURG, VA SP Assoc Anthropol & Ethnol Sci ID MITOCHONDRIAL-DNA; NEW-WORLD; PCR; AMPLIFICATION; SEQUENCES; POPULATIONS; EXTRACTION; DIVERSITY; BONE; FRAGMENTS AB The use of ancient DNA (aDNA) in the reconstruction of population origins and evolution is becoming increasingly common, However, contamination of ancient specimens and DNA extracts with modern DNA is more widespread than is generally acknowledged and remains a significant problem in aDNA analysis, Furthermore, studies of human aDNA are uniquely sensitive to contamination due to the continual presence of potential contamination sources and these studies require novel solutions for identification of contamination. Careful selection of polymorphic markers capable of discriminating between ancient DNA and probable DNA contaminants is critical. A promising new application of aDNA technology is the analysis of ancient human pathogens, which can be conducted with reduced risk of contamination. Fascinating questions to be addressed through ancient pathogen studies include the evolutionary history of pathogens and the migration patterns and evolutionary relationship of human populations. C1 Smithsonian Ctr Mat Res & Educ, Suitland, MD 20746 USA. RP Kolman, CJ (reprint author), Smithsonian Ctr Mat Res & Educ, Suitland, MD 20746 USA. NR 49 TC 4 Z9 4 U1 2 U2 2 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46295-8 PY 1999 BP 183 EP 200 PG 18 WC Biochemistry & Molecular Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Genetics & Heredity GA BP50B UT WOS:000085328900013 ER PT J AU Eble, GJ AF Eble, GJ TI Originations: Land and sea compared SO GEOBIOS LA English DT Article; Proceedings Paper CT Symposium on Paleodiversification - Land and Sea Compared CY JUL 06-08, 1998 CL UNIV CLAUDE BERNARD LYON I, LYON, FRANCE HO UNIV CLAUDE BERNARD LYON I DE origination; diversity; self-organization; land; sea ID SELF-ORGANIZED CRITICALITY; FOSSIL RECORD; EXTINCTION STATISTICS; HIGHER TAXA; PATTERNS; EVOLUTION; DIVERSIFICATION; DIVERSITY; MARINE; DYNAMICS AB The dynamics of origination in the fossil record of three marine groups (molluscs, echinoderms and fishes) and three terrestrial groups (mammals, insects and plants) is analyzed in this paper. Four hypotheses are tested: (1) secular decline in lineage origination; (2) secular decline in evolutionary innovation; (3) diversity dependence of lineage origination; (4) self-organized criticality of lineage origination. A decline in lineage origination and in the production of major innovations is present in all groups, suggesting controls that transcend the land-sea distinction. The relationship between diversity and origination appears to be strong in the sea and weak on land, a difference that might imply environment-specific controls. Mixed support for a logistic dynamics of origination is found. Finally, no general support for a self-organized critical behaviour of origination is found, with the predictions appearing to hold only in insects and pteridophytes/gymnosperms. C1 Smithsonian Inst, Museum Natl Hist Nat, Washington, DC 20560 USA. Santa Fe Inst, Santa Fe, NM 87501 USA. RP Eble, GJ (reprint author), Smithsonian Inst, Museum Natl Hist Nat, MRC-121, Washington, DC 20560 USA. NR 76 TC 16 Z9 16 U1 1 U2 2 PU UNIV CLAUDE BERNARD-LYONI PI VILLEURBANNE CEDEX PA CENTRE DES SCI DE LA TERRE 43 BLVD DU 11 NOVEMBRE, 69622 VILLEURBANNE CEDEX, FRANCE SN 0016-6995 J9 GEOBIOS-LYON JI Geobios PY 1999 VL 32 IS 2 BP 223 EP 234 DI 10.1016/S0016-6995(99)80036-9 PG 12 WC Paleontology SC Paleontology GA 200CB UT WOS:000080520600009 ER PT J AU Wilf, P Wing, SL Greenwood, DR Greenwood, CL AF Wilf, P Wing, SL Greenwood, DR Greenwood, CL TI Using fossil leaves as paleoprecipitation indicators: An Eocene example: Reply SO GEOLOGY LA English DT Article C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. Victoria Univ Technol, Sch Life Sci & Technol, Melbourne, Vic 8001, Australia. Monash Univ, Dept Geog & Environm Sci, Clayton, Vic 3168, Australia. RP Wilf, P (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. RI Greenwood, David/C-2758-2008; OI Greenwood, David/0000-0002-8569-9695; Wilf, Peter/0000-0001-6813-1937 NR 3 TC 13 Z9 13 U1 0 U2 9 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD JAN PY 1999 VL 27 IS 1 BP 92 EP 92 PG 1 WC Geology SC Geology GA 155EB UT WOS:000077932300024 ER PT S AU Narita, T Bloser, PF Grindlay, JE Jenkins, JA Yao, HW AF Narita, T Bloser, PF Grindlay, JE Jenkins, JA Yao, HW BE James, RB Schirato, RC TI Development of IMARAD CZT detectors with PIN contacts SO HARD X-RAY, GAMMA-RAY, AND NEUTRON DETECTOR PHYSICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Hard X-Ray, Gamma-Ray, and Neutron Detector Physics CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE CdZnTe; PIN; pixellated imaging detectors; hard X-ray imaging ID RADIATION DETECTORS; DESIGN AB We present initial results from our evaluation of a PIN contacted pixellated detector using cadimum zinc telluride substrate produced by IMARAD Imaging Systems. The Horizontal Bridgman (HB) grown crystals from IMARAD have been shown to produce high resolution photopeaks, but they are also seen to have large dark current. We seek to test whether the use of PIN contacts could reduce the dark current and thus improve the spectral response especially in the 10-100 keV energy range. We have fabricated PIN and MIN detectors with a 4 x 4 array of pixels on 10 x 10 mm substrates. Measurements of the detectors' dark current, spectral response, and internal electric field are presented and compared to IMARAD's ohmic contact detector and PIN detectors made of High Pressure Bridgman (HPB) material. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Narita, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 13 TC 12 Z9 12 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 0-8194-3254-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3768 BP 55 EP 65 DI 10.1117/12.366627 PG 11 WC Instruments & Instrumentation; Optics; Physics, Multidisciplinary; Physics, Condensed Matter SC Instruments & Instrumentation; Optics; Physics GA BN97V UT WOS:000083737600006 ER PT J AU Crombie, RI Gregory, KGK AF Crombie, RI Gregory, KGK TI A checklist of the herpetofauna of the Palau Islands (Republic of Belau), Oceania SO HERPETOLOGICAL MONOGRAPHS LA English DT Review DE micronesia; Palau Islands; amphibians; reptiles ID NEW-GUINEA; PACIFIC; EVOLUTION; GECKOS; REPTILIA; SCINCIDAE; EMOIA; EXPLOITATION; POPULATIONS; SYSTEMATICS AB The Palau islands of western Micronesia comprise one of the most physiographically varied archipelagos in the Pacific. There are some 350 islands of volcanic and coralline origin that range from Babeldaob at 333 km(2) (about 80% of Palau's total land area) to others, unnamed, that are less than one hectare. A barrier reef encircles most of the archipelago creating a lagoon up to 20 km wide. The majority of the islands are uninhabited, accessible with difficulty only by boat at high tide, and are densely vegetated over steep, rocky terrain. Because of their proximity to the Philippines, New Guinea, the Moluccas, and Borneo, the Palau islands host a significantly richer herpetofauna with more unique taxa than is found on other Pacific islands to the east. As with most other Pacific island groups, however the herpetofauna has been poorly documented. Since the earliest investigations that began in the nineteen century, Palau's herpetofauna has been uncovered piecemeal, No sustained held effort had been conducted until we began a systematic survey of the islands in 1992. Since then we have collected in Palau every month of the year at least once. This checklist of 46 species of reptiles and amphibians includes almost twice as many taxa as were known from Palau (Owen, 1977) at the beginning of our study Among these are new species or Palauan records of Gehyra, Hemiphyllodactylus, Lepidodactylus, Nactus, Perochirus, Emoia and Sphenomorphus. Because of the difficulties in surveying so many islands we believe that additional taxa and distributional records await discovery; even the smallest island in Palau can turn up surprises. Nonetheless. it is appropriate to consolidate what is now known about this intriguing fauna and environment. We provide an historical summary of previous collecting efforts, an overview of the islands' geology and habitats, and for each species account we include distributional information, taxonomic and systematic discussion, natural history observations, and a comprehensive bibliography. C1 US Natl Museum, Smithsonian Inst, Div Amphibians & Reptiles, Washington, DC 20560 USA. Univ San Diego, Dept Biol, San Diego, CA 92110 USA. RP Crombie, RI (reprint author), US Natl Museum, Smithsonian Inst, Div Amphibians & Reptiles, Washington, DC 20560 USA. NR 210 TC 28 Z9 35 U1 0 U2 1 PU HERPETOLOGISTS LEAGUE PI EMPORIA PA EMPORIA STATE UNIV, DIVISION BIOLOGICAL SCIENCES, 1200 COMMERCIAL ST, EMPORIA, KS 66801-5087 USA SN 0733-1347 EI 1938-5137 J9 HERPETOL MONOGR JI Herpetol. Monogr. PY 1999 VL 13 BP 29 EP 80 DI 10.2307/1467060 PG 52 WC Zoology SC Zoology GA 307RP UT WOS:000086667900002 ER PT J AU Bookidis, N Hansen, J Snyder, L Goldberg, P AF Bookidis, N Hansen, J Snyder, L Goldberg, P TI Dining in the sanctuary of Demeter and Kore at Corinth SO HESPERIA LA English DT Article ID PIGS C1 Amer Sch Class Studies Athens, Corinth Excavat, GR-10676 Athens, Greece. Boston Univ, Dept Archaeol, Boston, MA 02215 USA. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Bookidis, N (reprint author), Amer Sch Class Studies Athens, Corinth Excavat, 54 Odos Souidias, GR-10676 Athens, Greece. NR 76 TC 20 Z9 20 U1 0 U2 0 PU AMER SCHOOL CLASS STUDIES PI PRINCETON PA C/O INST FOR ADVANCED STUDY, PRINCETON, NJ 08540 USA SN 0018-098X J9 HESPERIA JI Hesperia PD JAN-MAR PY 1999 VL 68 IS 1 BP 1 EP 54 DI 10.2307/148389 PG 54 WC Archaeology SC Archaeology GA 187KR UT WOS:000079786200001 ER PT B AU Quataert, E AF Quataert, E BE Poutanen, J Svensson, R TI Particle heating in advection-dominated accretion flows SO HIGH ENERGY PROCESSES IN ACCRETING BLACK HOLES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Workshop on High Energy Processes in Accreting Black Holes CY JUN 29-JUL 04, 1998 CL GRAFTAVALLEN, SWEDEN SP Nord Inst Theoret Phys, Copenhagen, Theoret Astrophys Ctr, Copenhagen, Nord Acad Adv Studies, Swedish Nat Sci Res Council, Wennergren Fdn Scientif Res, Anna Greta & Holger Crafoord Fund ID ALFVENIC TURBULENCE AB I review particle heating by MHD turbulence in collisionless plasmas appropriate to advection-dominated accretion flows. These considerations suggest that the preferential turbulent heating of protons assumed by theoretical models is only achieved for relatively subthermal magnetic fields. 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 16 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 1-886733-81-3 J9 ASTR SOC P PY 1999 VL 161 BP 404 EP 409 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN27T UT WOS:000081412100038 ER PT B AU Psaltis, D Lamb, FK AF Psaltis, D Lamb, FK BE Poutanen, J Svensson, R TI Compton upscattering by accretion flows SO HIGH ENERGY PROCESSES IN ACCRETING BLACK HOLES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Workshop on High Energy Processes in Accreting Black Holes CY JUN 29-JUL 04, 1998 CL GRAFTAVALLEN, SWEDEN SP Nord Inst Theoret Phys, Copenhagen, Theoret Astrophys Ctr, Copenhagen, Nord Acad Adv Studies, Swedish Nat Sci Res Council, Wennergren Fdn Scientif Res, Anna Greta & Holger Crafoord Fund ID CONVERGING FLUID-FLOW; RADIATIVE-TRANSFER; TRANSFER EQUATION; MOVING-MEDIA; BLACK-HOLES; SCATTERING AB We discuss Compton scattering of photons by fast moving electrons in accretion flows around compact objects. We show that the spectra emerging from such systems depend sensitively on the detailed properties and radial profiles of the emission mechanisms within the flows and may or may not be power-law functions of photon energy. We therefore conclude that power-law high-energy spectra with particular spectral indices are not distinctive signatures of accreting black holes. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Psaltis, D (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 11 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 1-886733-81-3 J9 ASTR SOC P PY 1999 VL 161 BP 410 EP 415 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN27T UT WOS:000081412100039 ER PT B AU van Ballegooijen, AA Nisenson, P AF van Ballegooijen, AA Nisenson, P BE Rimmele, TR Balasubramaniam, KS Radick, RR TI Dynamics of magnetic elements in the photosphere and the formation of spicules SO HIGH RESOLUTION SOLAR PHYSICS: THEORY, OBSERVATIONS, AND TECHNIQUES SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT 19th NSO/SP International Workshop on High Resolution Solar Physics - Theory Observations and Techniques CY SEP 28-OCT 02, 1998 CL SUNSPOT, NM SP Natl Solar Observ, Natl Opt Astron Observ, NSF, Div Astron & Atmospher Sci, NASA, Off Space Sci, USAF, Off Sci Res, European Off Aerosp Res & Dev, Asian Off Aerosp Res & Dev, USAF, Res Labs, Space Hazards Branch ID SOLAR; RESOLUTION; MOTION; FIELDS; SUN AB We consider the proper motions of photospheric magnetic elements, and the effects of these motions on flows at larger heights. We summarize the results from recent analyses of high resolution G-band data obtained at the Swedish Vacuum Solar Telescope (SVST) on La Palma. The G-band images show small bright features which are known to correspond to kilogauss magnetic fields. We measure the motions of these bright points and find that the autocorrelation time of the bright point velocity is about 100 s. From the observed continuum intensity images, we derive a model of the granulation flow velocity as function of time and position on the Sun. We use this flow model to simulate the horizontal motions of photospheric magnetic elements, assuming that the elements are passively advected by the granulation flow. We find that this passive advection model is in reasonable agreement with the observed spatial distribution of the. G-band bright points. Finally, we use potential-field modeling to extrapolate the magnetic and velocity fields from the photosphere, where the flux tubes are well separated, to a height of 1500 km in the chromosphere, where the flux tubes fill the available volume due to the spreading out of the field lines. We find that strong shear flows occur near separatrix surfaces where neighboring flux tubes slide past each other in the chromosphere. We propose that spicules are formed in these separatrix layers. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP van Ballegooijen, AA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM vanballe@cfa.harvard.edu; pnisenson@cfa.harvard.edu NR 18 TC 6 Z9 6 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-009-9 J9 ASTR SOC P PY 1999 VL 183 BP 30 EP 35 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN98Q UT WOS:000083761400003 ER PT B AU Kaghashvili, EK Smartt, RN AF Kaghashvili, EK Smartt, RN BE Rimmele, TR Balasubramaniam, KS Radick, RR TI Fine-scale structure of coronal loops and consequences for coronal loop interactions SO HIGH RESOLUTION SOLAR PHYSICS: THEORY, OBSERVATIONS, AND TECHNIQUES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 19th NSO/SP International Workshop on High Resolution Solar Physics - Theory Observations and Techniques CY SEP 28-OCT 02, 1998 CL SUNSPOT, NM SP Natl Solar Observ, Natl Opt Astron Observ, NSF, Div Astron & Atmospher Sci, NASA, Off Space Sci, USAF, Off Sci Res, European Off Aerosp Res & Dev, Asian Off Aerosp Res & Dev, USAF, Res Labs, Space Hazards Branch ID X-RAY TELESCOPE; TRANSIENT BRIGHTENINGS; YOHKOH; FLARE AB Visible coronal emission-line images reveal occasional coronal loop interaction (CLI) events, as evidenced by transient brightenings at the projected intersection of adjacent loops. The image cadence is one minute with an angular resolution of, at best, 1 arcsec. Based on details revealed in the observations, these events are generally interpreted as due to the localized transient coalescence of two loops. Soft X-ray images suggest that brightenings can occur also in single loops. However, at least in some of these cases image processing that improves the effective angular resolution reveals that two loops are involved. Nevertheless, it is found that a plausible scenario, based on a 'non-rotating plane', can allow for single-loop brightenings. This theoretical study is supported by some simple numerical simulations of particular mechanisms. and some rough estimates of the likely energies involved in such processes. Finally, the model of a single loop brightening due to energy deposition at the site of a non-rotating plane is related to the case of observed two-loop interactions. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kaghashvili, EK (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 21 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 1-58381-009-9 J9 ASTR SOC P PY 1999 VL 183 BP 397 EP 404 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN98Q UT WOS:000083761400047 ER PT B AU Uitenbroek, H AF Uitenbroek, H BE Rimmele, TR Balasubramaniam, KS Radick, RR TI Imaging spectroscopy of CO lines compared with three-dimensional radiative transfer SO HIGH RESOLUTION SOLAR PHYSICS: THEORY, OBSERVATIONS, AND TECHNIQUES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 19th NSO/SP International Workshop on High Resolution Solar Physics - Theory Observations and Techniques CY SEP 28-OCT 02, 1998 CL SUNSPOT, NM SP Natl Solar Observ, Natl Opt Astron Observ, NSF, Div Astron & Atmospher Sci, NASA, Off Space Sci, USAF, Off Sci Res, European Off Aerosp Res & Dev, Asian Off Aerosp Res & Dev, USAF, Res Labs, Space Hazards Branch ID SOLAR CARBON-MONOXIDE; SPECTROMETER OBSERVATIONS; BANDS; QUIET AB Spectroscopic imaging observations of the CO fundamental vibration-rotation transitions at 4.6 mu m, obtained at the Kitt Peak McMath-Pierce facility, show that the dynamics of both the solar granulation and, to a lesser extent, the five-minute oscillations play an important role in CO line formation. Spectro-heliograms made in the core of strong CO lines display an inverted granular contrast with dark areas corresponding to granule centers, and a bright network corresponding to the inter-granular lanes. This observation is confirmed by multi-dimensional radiative transfer modeling of CO line formation in a solar convection simulation snapshot. In addition, such transfer calculations allow us to interpret the observed pattern, and to predict 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 up-flowing material runs into the steep density gradient of the stable layer above the photosphere. Unfortunately, current granulation simulations do not extend to high enough layers in the atmosphere to model formation of CO lines close to the solar limb where they exhibit; their anomalous temperature behavior. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Uitenbroek, H (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 10 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 1-58381-009-9 J9 ASTR SOC P PY 1999 VL 183 BP 486 EP 493 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN98Q UT WOS:000083761400058 ER PT B AU Mathur, S Marshall, H Evans, N Green, P Wilkes, B AF Mathur, S Marshall, H Evans, N Green, P Wilkes, B BE Bunker, AJ VanBreugel, WJM TI ChaMP and the high redshift quasars in X-rays SO HY-REDSHIFT UNIVERSE: GALAXY FORMATION AND EVOLUTION AT HIGH REDSHIFT SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT International Meeting on the Hy-Redshift Universe - Galaxy Formation and Evolution at High Redshift CY JUN 21-24, 1999 CL UNIV CALIF, BERKELEY, CA SP Univ Calif HO UNIV CALIF AB Chandra X-ray Observatory, (formerly known as AXAF), will observe down to the flux limit of 2x10(-16) erg s(-1) cm(-2). In its first year of operation Chandra's CCD detectors will observe over 1500 quasars serendipitously in the soft (0.5-3.5 keV) band. Over 200 quasars will be detected in X-rays in the redshift range 3 < z < 4 and over 400 quasars in 2 < z < 3. This will enable us to determine the high redshift X-ray luminosity function. This is the contribution by unabsorbed sources only. The total numbers would be larger by similar to 60%. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Mathur, S (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 4 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 1-58381-019-6 J9 ASTR SOC P PY 1999 VL 193 BP 612 EP 617 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP85L UT WOS:000086435200082 ER PT J AU Rasmussen, PC Collar, NJ AF Rasmussen, PC Collar, NJ TI Major specimen fraud in the Forest Owlet Heteroglaux (Athene auct.) blewitti SO IBIS LA English DT Article AB The Forest Owlet Heteroglaux (Athene auct.) blewitti is known from central India from seven old specimens, four of which were taken in northwest Maharashtra in 1880-83 by J. Davidson and the last purportedly in Gujarat over 30 years later by R. Meinertzhagen. Because of recently documented specimen fraud by Meinertzhagen, we subjected his Forest Owlet specimen to scrutiny (including X-rays) and established that it had been extensively remade in a way that transformed its original appearance. Moreover, it shows several features - tying of distal humeri from the outside, cotton wing-stuffing identical to that from a Davidson bird, original retention of humerus and formerly a stretched neck that identify its true collector as Davidson. Examination of the Natural History Museum's catalogue reveals that a fifth Davidson specimen, collected in 1884 in the area where his first four were taken, was registered in 1925 but is now missing, although not logged as lost, sold or exchanged. Meinertzhagen's diary and specimen catalogue strongly suggest that he was not in Gujarat on the date given for his 1914 specimen, and he surprisingly never published the record, despite its exceptional rarity. We conclude that he stole the fifth Davidson Forest Owlet specimen from the Natural History Museum, and remade and relabelled it to conceal its origin, thereby compromising the geographic and temporal record of this critically threatened species. C1 Smithsonian Inst, Div Birds, Washington, DC 20560 USA. Birdlife Int, Cambridge CB3 0NA, England. RP Rasmussen, PC (reprint author), Smithsonian Inst, Div Birds, NHB Room 336,MRC 114, Washington, DC 20560 USA. NR 20 TC 7 Z9 13 U1 2 U2 3 PU BRITISH ORNITHOLOGISTS UNION PI TRING PA C/O NATURAL HISTORY MUSEUM, SUB-DEPT ORNITHOLOGY, TRING, HERTS, ENGLAND HP23 6AP SN 0019-1019 J9 IBIS JI Ibis PD JAN PY 1999 VL 141 IS 1 BP 11 EP 21 PG 11 WC Ornithology SC Zoology GA 154TY UT WOS:000077906200002 ER PT J AU Dowsett, RJ Olson, SL Roy, MS Dowsett-Lemaire, F AF Dowsett, RJ Olson, SL Roy, MS Dowsett-Lemaire, F TI Systematic status of the black-collared bulbul Neolestes torquatus SO IBIS LA English DT Article ID DNA; BIRDS AB The Afrotropical monotypic genus Neolestes has been treated variously as a bulbul (Pycnonotidae) or a 'shrike' (Malaconotidae, Laniidae or Prionopidae). Recent field observations and fresh laboratory material have enabled a multi-disciplinary review incorporating biology, anatomy and DNA. The DNA analysis suggests that N. torquatus represents a deep branch of the pycnonotid clade. The plumage of Neolestes is unlike that of any bulbul, although the juvenile plumage is more bulbul-like than shrike-like. Evidence from the syrinx, skull, humerus and carpometatarsus eliminates a relationship between Neolestes and the shrikes and mainly points to one with the Pycnonotidae. Neolestes could be the primitive sister-group of the Pycnonotidae, or a member of some larger group of which the bulbuls are but one manifestation. The vocalizations are not shrike-like but are reminiscent of those of the African species of Pycnonotus; other aspects of its behaviour point in this direction. We believe there is no evidence for considering Neolestes to be a 'shrike', and recommend treating it as a primitive member of the Pycnonotidae, although as incertae sedis. C1 Smithsonian Inst, Museum Natl Hist Nat, Dept Vertebrate Zool, Washington, DC USA. Univ Copenhagen, Inst Zool, Dept Populat Biol, DK-2100 Copenhagen, Denmark. RP Dowsett, RJ (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Vertebrate Zool, Washington, DC USA. EM Dowsette@aol.com NR 35 TC 2 Z9 3 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0019-1019 J9 IBIS JI Ibis PD JAN PY 1999 VL 141 IS 1 BP 22 EP 28 PG 7 WC Ornithology SC Zoology GA 154TY UT WOS:000077906200003 ER PT J AU Ceruzzi, P AF Ceruzzi, P TI 1998 George R. Stibitz Computer Pioneer Awards SO IEEE ANNALS OF THE HISTORY OF COMPUTING LA English DT Biographical-Item C1 Smithsonian Inst, Natl Air & Space Museum, Washington, DC 20560 USA. RP Ceruzzi, P (reprint author), Smithsonian Inst, Natl Air & Space Museum, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1058-6180 J9 IEEE ANN HIST COMPUT JI IEEE Ann. Hist. Comput. PD JAN-MAR PY 1999 VL 21 IS 1 BP 71 EP 72 PG 2 WC Computer Science, Theory & Methods; History & Philosophy Of Science SC Computer Science; History & Philosophy of Science GA 160JJ UT WOS:000078226600027 ER PT J AU Ceruzzi, P AF Ceruzzi, P TI Journey to the Moon: The history of the Apollo guidance computer SO IEEE ANNALS OF THE HISTORY OF COMPUTING LA English DT Book Review C1 Smithsonian Inst, Natl Air & Space Museum, Washington, DC 20560 USA. RP Ceruzzi, P (reprint author), Smithsonian Inst, Natl Air & Space Museum, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1058-6180 J9 IEEE ANN HIST COMPUT JI IEEE Ann. Hist. Comput. PD JAN-MAR PY 1999 VL 21 IS 1 BP 78 EP 79 PG 2 WC Computer Science, Theory & Methods; History & Philosophy Of Science SC Computer Science; History & Philosophy of Science GA 160JJ UT WOS:000078226600035 ER PT J AU Inoue, T Roubik, DW Suka, T AF Inoue, T Roubik, DW Suka, T TI Nestmate recognition in the stingless bee Melipona panamica (Apidae, Meliponini) SO INSECTES SOCIAUX LA English DT Article DE Melipona panamica; stingless bees; Apidae; nestmate recognition; worker oviposition ID KIN RECOGNITION; HONEY-BEE; HYMENOPTERA; ODOR AB Nestmate recognition was studied in the Neotropical stingless bee Melipona panamica, a species in which workers "sneak" their own reproductive eggs into 1% of brood cells. We manipulated four factors that could influence individual recognition cues: the mother queen, the environment during the immature stage, the environment during the early adult stage, and worker age. We also simulated the action of natural enemies on colonies tested for discrimination of such worker characteristics. All factors that we tested affected responses of the discriminating workers, which could recognize sisters, nieces and unrelated workers. Previous exposure of unrelated callow bees to the odor of the host nest greatly increased chances of acceptance by the host colony. Probability of acceptance decreased, however, with increasing age of introduced bees or increasing disturbance of the host colony. These complexities in patterns of nestmate recognition and nest defense are adequately explained from the standpoint of inclusive fitness of the discriminating workers. Differences in nestmate recognition and worker egg laying among Meliponini are also discussed. C1 Smithsonian Trop Res Inst, Balboa, Panama. Kyoto Univ, Ctr Ecol Res, Otsu, Shiga 52001, Japan. Kyoto Univ, Fac Agr, Entomol Lab, Kyoto 606, Japan. RP Roubik, DW (reprint author), Smithsonian Trop Res Inst, APDO 2072, Balboa, Panama. NR 33 TC 33 Z9 34 U1 1 U2 10 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0020-1812 J9 INSECT SOC JI Insect. Soc. PY 1999 VL 46 IS 3 BP 208 EP 218 DI 10.1007/s000400050136 PG 11 WC Entomology SC Entomology GA 228ZT UT WOS:000082168000003 ER PT J AU Linares, OF AF Linares, OF TI Shrines of the slave trade: Diola religion and society in precolonial Senegal SO INTERNATIONAL JOURNAL OF AFRICAN HISTORICAL STUDIES LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Linares, OF (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AFRICAN STUDIES CENTER PI BOSTON PA BOSTON UNIVERSITY 270 BAY STATE ROAD, BOSTON, MA 02215 USA SN 0361-7882 J9 INT J AFR HIST STUD JI Int. J. Afr. Hist. Stud. PY 1999 VL 32 IS 1 BP 130 EP 130 DI 10.2307/220810 PG 1 WC History SC History GA 295RD UT WOS:000085980900008 ER PT J AU Hope, WD Tchesunov, AV AF Hope, WD Tchesunov, AV TI Smithsoninema inaequale n.g. and n.sp (Nematoda, Leptolaimidae) inhabiting the test of a foraminiferan SO INVERTEBRATE BIOLOGY LA English DT Article DE Camacolaiminae; onchiostyle ID METAZOANS AB Smithsoninema inaequale n.g., n.sp. (Nematoda: Leptolaimidae: Camacolaiminae) is described from one male and one female specimen taken from within an arenaceous foraminiferan, Vanhoeffenella aff. gaussi RHUMBLER 1905 (Foraminifera: Astrorhizidae) collected off the coast of Luanda, Angola. The male has a cuticularized, stylet-like thickening of the dorsal buccal wall, and the posterior end of the esophagus is glandular and elongated as in members of Anguninoides and Onchium (Camacolaiminae). Smithsoninema n.g. is characterized by its strong sexual dimorphism. Males are long, slender, and structurally similar to other males of Camacolaiminae. Females are short and stout, with a voluminous, trophosome-like midgut devoid of an internal lumen. The rectum and anus are vestigial. Through the transparent walls of the test it was possible to see the male and female nematodes enclosed within the theca of the foraminiferan. The nematodes were probably parasites, or endo-predators, rather than inquilines. Camacolaiminae is redefined and Nemella COBB 1920 is synonymized with Ionema COBB 1920. Dagda SOUTHERN 1914 and Diodontolaimus SOUTHERN 1914 are transferred to Camacolaiminae, although Dagda asymmetrica GERLACH 1953, D. phinneyi MURPHY 1964, and Diodontolaimus tenuispiculum GERLACH 1955 are transferred from their respective genera to Procamacolaimus. Eontolaimus FURSTENBERG & VINCX 1988 is synonymized with Listia BLOME 1982 (Leptolaiminae). A key to the genera of Camacolaiminae is provided. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Moscow MV Lomonosov State Univ, Fac Biol, Dept Invertebrate Zool, Moscow 119899, Russia. RP Hope, WD (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 27 TC 12 Z9 12 U1 0 U2 2 PU AMER MICROSCOPICAL SOC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 USA SN 1077-8306 J9 INVERTEBR BIOL JI Invertebr. Biol. PY 1999 VL 118 IS 2 BP 95 EP 108 DI 10.2307/3227052 PG 14 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 208UG UT WOS:000081009800003 ER PT J AU Leal, JH Harasewych, MG AF Leal, JH Harasewych, MG TI Deepest Atlantic molluscs: hadal limpets (Mollusca, Gastropoda, Cocculiniformia) from the northern boundary of the Caribbean Plate SO INVERTEBRATE BIOLOGY LA English DT Article DE deep-sea; Cocculinidae; Pseudococculinidae ID ARCHAEOGASTROPODA; SYSTEMATICS; ANATOMY; SEA; AFFINITIES; PHYLOGENY; EVOLUTION; PACIFIC AB Descriptions and scanning electron micrographs of the shell, protoconch, radula, and gross external anatomy are provided for four species of cocculiniform limpets collected from hadal depths of the Cayman and Puerto Rico trenches. Of these, one represents a new genus and species, Macleaniella moskalevi (Cocculinidae), endemic to the Puerto Rico Trench. Another, Amphiplica plutonica (Pseudococculinidae), represents a new species from the Cayman Trench of a globally distributed abyssal genus. The original descriptions of the remaining two species, Fedikovella caymanensis (Cocculinidae) and Caymanabyssia spina (Pseudococculinidae), both from the Cayman Trench and type species of their respective genera, contained only poorly reproduced illustrations of portions of the shells, and line drawings of isolated rows of radular teeth. These four species, each apparently endemic to their respective trenches, represent the deepest records of molluscs collected in the Atlantic Ocean. C1 Bailey Matthews Shell Museum, Sanibel, FL 33957 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Leal, JH (reprint author), Bailey Matthews Shell Museum, 3075 Sanibel Captiva Rd, Sanibel, FL 33957 USA. EM leal@water.net NR 48 TC 17 Z9 17 U1 0 U2 7 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1077-8306 J9 INVERTEBR BIOL JI Invertebr. Biol. PY 1999 VL 118 IS 2 BP 116 EP 136 DI 10.2307/3227054 PG 21 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 208UG UT WOS:000081009800005 ER PT J AU Strong, EE Harasewych, MG AF Strong, EE Harasewych, MG TI Anatomy of the hadal limpet Macleaniella moskalevi (Gastropoda, Cocculinoidea) SO INVERTEBRATE BIOLOGY LA English DT Article DE mollusca; deep-sea ID DEEP-SEA; ARCHAEOGASTROPODA; MOLLUSCA; SYSTEMATICS; BONE AB The anatomy of the hadal, cocculinid limpet Macleaniella moskalevi is described. This species has a small, symmetrical, cap-shaped shell with a prominent internal transverse septum. As in other cocculinid genera, broad oral lappets and epipodial tentacles are present. Vestigial eyes are also present, but lack pigment and are modified into the basitentacular gland. The unique aortic vessel and associated hemal gland are present. Mantle cavity morphology is characteristic of cocculinid taxa; the cavity contains a pseudoplicatid gill, hypobranchial gland, and shallow brood pouch. Adults are simultaneous hermaphrodites, possessing a gonad with distinct egg and sperm producing regions; the common gonoduct is glandular. The single receptaculum seminis is connected to the anterior gonoduct via an enclosed duct. An enlarged right cephalic tentacle is inferred to function as a copulatory organ. The digestive gland occupies that part of the visceral mass confined above the septum and opens by way of two ducts into the distal esophagus. The anterior digestive tract is characterized by the presence of extremely well-developed esophageal pouches, a cuticularized sublingual pouch, and an unpaired jaw. A subradular sense organ and salivary glands are lacking. M. moskalevi is remarkably unique among previously described cocculinids in the anatomy of the reproductive tract and of the organs associated with the mantle cavity. In particular, the conformation of the nervous system in this species is unknown among cocculinids described thus far. C1 George Washington Univ, Dept Biol Sci, Washington, DC 20052 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Strong, EE (reprint author), George Washington Univ, Dept Biol Sci, Washington, DC 20052 USA. OI Strong, Ellen/0000-0001-7181-4114 NR 26 TC 7 Z9 7 U1 0 U2 4 PU AMER MICROSCOPICAL SOC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 USA SN 1077-8306 J9 INVERTEBR BIOL JI Invertebr. Biol. PY 1999 VL 118 IS 2 BP 137 EP 148 DI 10.2307/3227055 PG 12 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 208UG UT WOS:000081009800006 ER PT J AU Henson, PM AF Henson, PM TI "Objects of curious research" - The history of science and technology at the Smithsonian SO ISIS LA English DT Review C1 Smithsonian Inst Archives Arts & Ind 2135, Washington, DC 20560 USA. RP Henson, PM (reprint author), Smithsonian Inst Archives Arts & Ind 2135, Washington, DC 20560 USA. NR 107 TC 6 Z9 6 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0021-1753 J9 ISIS JI Isis PY 1999 VL 90 SU S BP S249 EP S269 DI 10.1086/384619 PG 21 WC History & Philosophy Of Science SC History & Philosophy of Science GA 248VC UT WOS:000083295600016 ER PT S AU Marvin, UB AF Marvin, UB BE Craig, GY Hull, JH TI Impacts from space: the implications for uniformitarian geology SO JAMES HUTTON - PRESENT AND FUTURE SE Geological Society Special Publication LA English DT Review CT Conference on John Hutton - Present and Future CY AUG 05-09, 1997-1998 CL ROYAL COLL PHYSICIANS, EDINBURGH, SCOTLAND SP Brewin Dolphin & Co Ltd, R & K Drysdale Ltd, Dunstaffnage Marine Lab, Edinburgh Geol Soc, Hunters Coaches, Open Univ, City Edinburgh, Univ Edinburgh Dept Geol & Geophys, Univ Edinburgh, Amerada Hess Ltd, Amoco Serv Ltd, ARCO British Ltd, BP Explorat Operating Co Ltd, Chevron Europe Ltd, Conoco (Europe) Ltd, IKODA Ltd, Kerr McGee Oil (UK) LTD, Oryx UK Energy co, Ready Mixed Concrete (UK) Ltd, Shell UK Explorat & Prod, Statoil (UK) Ltd HO ROYAL COLL PHYSICIANS ID CRETACEOUS-TERTIARY BOUNDARY; PERIODIC MASS EXTINCTIONS; COMET SHOWERS; CHICXULUB CRATER; GALACTIC PLANE; METEORITE; EARTH; ORIGIN; AGES AB The geological implications of the Earth's collisions with other bodies in space have become fully evident only since the opening of the Space Age. In the early eighteenth century, most western natural philosophers accepted the view, inherited from Aristotle and confirmed on mechanistic grounds by Isaac Newton, that interplanetary space is empty of solid matter. In the final decade of that century, two books, one by Ernst F. F. Chladni of Wittenberg and one by James Hutton of Edinburgh, contributed to the rise of meteorite studies and uniformitarian geology, respectively. Although they arose almost simultaneously, these two branches of science, one of which postulated the fall to Earth of solid bodies from space while the other endorsed only strictly endogenous processes acting upon the Earth, evolved separately over the next 200 years. This paper traces the long estrangement between mainstream geology and the science of meteorites. The two disciplines collided head-on in 1980 when a team of scientists headed by the physicist, Luis Alvarez, of the University of California, hypothesized that the massive extinctions at the end of the Cretaceous were triggered by the hypervelocity impact of a large body from space. Many geologists rejected outright such an exotic cause. More recently, as evidence has accumulated for the K-T impact as well as for many other crater-forming impacts, we are beginning to realize that unpredictable collisions have played a role of fundamental importance throughout the history of the solar system. 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 128 TC 9 Z9 9 U1 2 U2 4 PU GEOLOGICAL SOC PUBLISHING HOUSE PI BATH PA UNIT 7, BRASSMILL ENTERPRISE CTR, BRASSMILL LANE, BATH BA1 3JN, AVON, ENGLAND SN 0305-8719 BN 1-86239-026-6 J9 GEOL SOC SPEC PUBL PY 1999 VL 150 BP 89 EP 117 DI 10.1144/GSL.SP.1999.150.01.06 PG 29 WC Geology SC Geology GA BM55N UT WOS:000079091800006 ER PT J AU Erwin, DH AF Erwin, DH TI Biospheric perturbations during Gondwanan times: from the Neoproterozoic-Cambrian radiation to the end-Permian crisis SO JOURNAL OF AFRICAN EARTH SCIENCES LA English DT Article ID FOSSIL RECORD; ORDOVICIAN RADIATION; MARINE DIVERSITY; MASS EXTINCTION; EVOLUTION; TRENDS; COMMUNITIES; PATTERNS; ANIMALS; ECOLOGY AB The history of marine life during the Palaeozoic is structured by the Neoproterozoic-Early Cambrian radiation, the Ordovician radiation and a diversity plateau from the Late Ordovician into the Permian. This plateau is punctuated by mass extinctions in the end-Ordovician, Late Devonian, and finally the catastrophic end-Permian mass extinction, which brings the Palaeozoic to a close. Underlying these radiations and extinctions is a constant pattern of evolutionary change, as species respond to environmental changes, biological innovations, shifting biogeography and other factors. Are these patterns structured by global processes, or are they the summation of a host of local and regional events? One school of palaeontologists has argued that these patterns are driven by biotic interactions on a global scale, with mass extinctions as perturbations to longer-term processes, but with little lasting effect. Others have accorded the primary influence to radiations and mass extinctions. New studies from of the Ordovician radiation support a third possibility, that global signals are the summation of events at scales from local to global mass extinctions. Variations in biotic diversity, at scales ranging from global evolutionary radiations and mass extinctions to regional fluctuations or the changing fortunes of individual community assemblages, reflects the vicissitudes of environmental circumstance. Determining the appropriate level of analysis (global, regional or local) will require greater biogeographic data, particularly from Gondwanan continents. This will allow the development of explicit, testable models linking geological, geochemical and palaeontological patterns to common processes. (C) 1999 Elsevier Science Limited. All rights reserved. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. RP Erwin, DH (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, MRC-121, Washington, DC 20560 USA. RI Erwin, Douglas/A-9668-2009 NR 69 TC 6 Z9 8 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0899-5362 J9 J AFR EARTH SCI JI J. Afr. Earth Sci. PD JAN PY 1999 VL 28 IS 1 BP 115 EP 127 DI 10.1016/S0899-5362(99)00021-4 PG 13 WC Geosciences, Multidisciplinary SC Geology GA 208DC UT WOS:000080974100009 ER PT J AU Prussin, L AF Prussin, L TI Drawn from African dwellings. SO JOURNAL OF AFRICAN HISTORY LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Prussin, L (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0021-8537 J9 J AFR HIST JI J. Afr. Hist. PY 1999 VL 40 IS 1 BP 168 EP 169 PG 2 WC History SC History GA 185TM UT WOS:000079686500036 ER PT J AU Eltz, T Whitten, WM Roubik, DW Linsenmair, KE AF Eltz, T Whitten, WM Roubik, DW Linsenmair, KE TI Fragrance collection, storage, and accumulation by individual male orchid bees SO JOURNAL OF CHEMICAL ECOLOGY LA English DT Article DE Euglossine bees; fragrance collection; sexual selection; species recognition; CC-MS ID MALE EUGLOSSINE BEES; HANDICAP PRINCIPLE; APIDAE; HYMENOPTERA; SELECTION AB Individually marked males of two species of Euglossa were sighted repeatedly and over considerable periods of time (up to 44 days) at artificial fragrance baits exposed on Barro Colorado Island (BCI), Panama. Individuals switched between different bait chemicals that are attractive for the respective species, and no bait preferences or individual bait constancy was observed. CC-MS analyses of 153 males of three species showed that individual hind tibiae contain highly variable quantities of a complex and species-specific blend of fragrance compounds, mainly terpenoids and aromatics. In all three species, frequency distributions of individual quantities were strongly skewed towards individuals with small amounts, and individual amount and complexity were positively correlated. Tibial contents of male Euglossa imperialis that were kept alive in a flight cage for 0, 5, 10, or 15 days showed no qualitative or quantitative change over time, suggesting that the fragrances are very efficiently stored in the hind legs. In Euglossa cognata wing wear, an established age correlate of the species, was positively correlated with individual fragrance quantity. Our results suggest that male euglossines forage continuously for a variety of volatiles, store them, and finally acquire large quantities of a complex and specific fragrance bouquet. Both qualitative and quantitative aspects of individual contents are likely to contain information on male phenotypic and genotypic quality. C1 Univ Wurzburg, Dept Anim Ecol & Trop Biol Zool 3, D-97074 Wurzburg, Germany. Univ Florida, Florida Museum Nat Hist, Gainesville, FL 32611 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Eltz, T (reprint author), Univ Wurzburg, Dept Anim Ecol & Trop Biol Zool 3, Hubland, D-97074 Wurzburg, Germany. NR 28 TC 73 Z9 81 U1 2 U2 18 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0098-0331 J9 J CHEM ECOL JI J. Chem. Ecol. PD JAN PY 1999 VL 25 IS 1 BP 157 EP 176 DI 10.1023/A:1020897302355 PG 20 WC Biochemistry & Molecular Biology; Ecology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology GA 162AX UT WOS:000078323800010 ER PT J AU Catao-Dias, JL Nichols, DK AF Catao-Dias, JL Nichols, DK TI Neoplasia in snakes at the National Zoological Park, Washington, DC (1978-1997) SO JOURNAL OF COMPARATIVE PATHOLOGY LA English DT Article ID ZOO ANIMALS AB Of 291 juvenile and adult snakes examined Post mortem over a 20-year period (1978-1997) at the National Zoological Park (NZP) in Washing-ton, DC, 36 (24 females and 12 males) had neoplasms. Two snakes had tumours of two or three different types, but the other 34 snakes had only one type. All affected animals were adults and their average time on exhibit at the NZP was 108.9 months, Malignant neoplasms (79.5%) outnumbered benign neoplasms (20.5%). Of the malignant: tumours, 19 (61.3%) were considered to have arisen in mesenchymal tissues, 11 (35.5%) were of epithelial origin, and one (3.2%) was derived from neuroectodermal tissues. All the benign neoplasms were of epithelial origin. Neoplasms of the lymphoid and haematopoietic tissues were the most common (12 cases), followed by tumours of the liver and biliary tract (seven cases) and the gastrointestinal tract (four cases). (C) 1999 W.B. Saunders Company Limited. C1 Univ Sao Paulo, Fac Vet Med & Zootechny, Dept Pathol, BR-05508000 Sao Paulo, Brazil. Smithsonian Inst, Natl Zool Pk, Dept Pathol, Washington, DC 20008 USA. RP Catao-Dias, JL (reprint author), Univ Sao Paulo, Fac Vet Med & Zootechny, Dept Pathol, Av Dr Orlando Marques Paiva,87 Cidade Univ, BR-05508000 Sao Paulo, Brazil. RI Catao-Dias, Jose Luiz/C-4897-2012 OI Catao-Dias, Jose Luiz/0000-0003-2999-3395 NR 18 TC 34 Z9 37 U1 3 U2 7 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0021-9975 J9 J COMP PATHOL JI J. Comp. Pathol. PD JAN PY 1999 VL 120 IS 1 BP 89 EP 95 DI 10.1053/jcpa.1998.0253 PG 7 WC Pathology; Veterinary Sciences SC Pathology; Veterinary Sciences GA 157WY UT WOS:000078085700007 PM 10098018 ER PT J AU Correll, DL Jordan, TE Weller, DE AF Correll, DL Jordan, TE Weller, DE TI Effects of precipitation and air temperature on phosphorus fluxes from Rhode River watersheds SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID COASTAL-PLAIN WATERSHEDS; NUTRIENT DYNAMICS; CHESAPEAKE BAY; LAND-USE; EXPORT; FOREST; DISCHARGES; TRANSPORT; STREAM AB We studied fluxes of total P, total phosphate, and total organic P from seven contiguous small watersheds on the Atlantic Coastal Plain in Maryland for up to 25 yr. These watersheds have perched aquifers so all groundwater discharges as well as surface runoff were measured at V-notch weirs equipped with volume-integrating, flow-proportional samplers. Interannnal variations in annual and seasonal precipitation during this study spanned approximately the range of 160-yr weather records in the region. Annual total-P area yields from the overall watershed varied 28-fold, correlations of all P-species fluxes with precipitation were highly significant, and power function regressions of precipitation vs. P-flux explained from 42 to 55% of the variance in the latter. Phosphorus fluxes from a cropland watershed mere much higher and more variable with volume of precipitation, while fluxes from a forested watershed were much lower and primarily composed of organic P. Correlations of P fluxes with precipitation were higher in the spring. Annual and seasonal P concentrations also often increased significantly with precipitation. Variations in seasonal mean air temperature sometimes explained significant amounts of variance in P fluxes, especially phosphate from cropland. A regression model was used to construct graphical and tabular summaries. 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 30 TC 21 Z9 21 U1 1 U2 8 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD JAN-FEB PY 1999 VL 28 IS 1 BP 144 EP 154 PG 11 WC Environmental Sciences SC Environmental Sciences & Ecology GA 159QJ UT WOS:000078184900017 ER PT J AU Huelsenbeck, JP Nielsen, R AF Huelsenbeck, JP Nielsen, R TI Variation in the pattern of nucleotide substitution across sites SO JOURNAL OF MOLECULAR EVOLUTION LA English DT Article DE likelihood-ratio testing; maximum likelihood; molecular evolution; molecular systematics; phylogeny ID MAXIMUM-LIKELIHOOD-ESTIMATION; DNA-SEQUENCES; MITOCHONDRIAL-DNA; PHYLOGENETIC ANALYSIS; MOLECULAR CLOCK; RATES; HETEROGENEITY; MODELS AB A model of nucleotide substitution that allows the transition/transversion rate bias to vary across sites was constructed. We examined the fit of this model using likelihood-ratio tests by analyzing 13 protein coding genes and 1 pseudogene. Likelihood-ratio testing indicated that a model that allows variation in the transition/transversion rate bias across sites provided a significant improvement in fit for most protein coding genes but not for the pseudogene. When the analysis was repeated with parameters estimated separately for first, second, and third codon positions, strong heterogeneity was uncovered for the first and second codon positions; the variation in the transition/transversion rate was generally weaker at the third codon position. The transition rate bias and branch lengths are underestimated when variation in the transition/transversion rate was not accommodated, suggesting that it may be important to accommodate variation in the pattern of nucleotide substitution for accurate estimation of evolutionary parameters. C1 Smithsonian Museum Support Ctr, Lab Mol systemat, Suitland, MD 20746 USA. Univ Calif Berkeley, Dept Integrat Biol, Berkeley, CA 94720 USA. RP Huelsenbeck, JP (reprint author), Smithsonian Museum Support Ctr, Lab Mol systemat, 4210 Silver Hill Rd, Suitland, MD 20746 USA. RI Nielsen, Rasmus/D-4405-2009; Huelsenbeck, John/C-6398-2013 OI Nielsen, Rasmus/0000-0003-0513-6591; NR 27 TC 24 Z9 25 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0022-2844 J9 J MOL EVOL JI J. Mol. Evol. PD JAN PY 1999 VL 48 IS 1 BP 86 EP 93 DI 10.1007/PL00006448 PG 8 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 154FH UT WOS:000077877700009 PM 9873080 ER PT J AU Ackerman, MS Mandel, E AF Ackerman, MS Mandel, E TI Memory in the small: Combining collective memory and task support for a scientific community SO JOURNAL OF ORGANIZATIONAL COMPUTING AND ELECTRONIC COMMERCE LA English DT Article DE organizational memory; collective memory; scientific community; computer-supported cooperative work; scientific applications; information spaces; task support AB Many forms of memory exist embedded within the processes and tasks of an organization or community. Memory in the small, or memory utilized in the performance of an institutionally important task, serves as an effective task support mechanism. By basing memory on tasks (and basing task support on memory), memory systems can provide additional and necessary support services for organizations and communities. As an example of memory in the small, in this article we describe a software system, called the ASSIST, that combines memory with task performance for a scientific community. The ASSIST utilizes and stores the collective memory of astrophysicists about data analysis, and is used worldwide by astrophysicists. In this article, we also consider the architectural and theoretical issues involved when combining memory with task performance. C1 Univ Calif Irvine, Dept Informat & Comp Sci, Irvine, CA 92697 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ackerman, MS (reprint author), Univ Calif Irvine, Dept Informat & Comp Sci, Irvine, CA 92697 USA. NR 36 TC 7 Z9 7 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 1091-9392 J9 J ORG COMP ELECT COM JI J. Organ. Comp. Electron. Commer. PY 1999 VL 9 IS 2-3 BP 105 EP 127 DI 10.1207/s15327744joce0902&3_2 PG 23 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications SC Computer Science GA 289CT UT WOS:000085602300002 ER PT J AU Sohn, IG Swain, FM AF Sohn, IG Swain, FM TI On the superfamily Darwinuloidacea, the type species of Darwinuloidea Mandelstam, 1956, and on the status of Cheikella Sohn and Morris, 1963 (Ostracoda) SO JOURNAL OF PALEONTOLOGY LA English DT Article C1 US Geol Survey, Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. Univ Minnesota, Dept Geol & Geophys, Minneapolis, MN 55455 USA. RP Sohn, IG (reprint author), US Geol Survey, Smithsonian Inst, Natl Museum Nat Hist, Room E308, Washington, DC 20560 USA. NR 19 TC 4 Z9 4 U1 0 U2 0 PU PALEONTOLOGICAL SOC INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0022-3360 J9 J PALEONTOL JI J. Paleontol. PD JAN PY 1999 VL 73 IS 1 BP 159 EP 160 PG 2 WC Paleontology SC Paleontology GA 164YN UT WOS:000078491300013 ER PT J AU Rodrigues, R Jucks, KW Lacome, N Blanquet, G Walrand, J Traub, WA Khalil, B Le Doucen, R Valentin, A Camy-Peyret, C Bonamy, L Hartmann, JM AF Rodrigues, R Jucks, KW Lacome, N Blanquet, G Walrand, J Traub, WA Khalil, B Le Doucen, R Valentin, A Camy-Peyret, C Bonamy, L Hartmann, JM TI Model, software, and database for computation of line-mixing effects in infrared Q branches of atmospheric CO2 - I. Symmetric isotopomers SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID TUNABLE-DIODE-LASER; CARBON-DIOXIDE; TEMPERATURE-DEPENDENCE; MU-M; THEORETICAL-ANALYSIS; ABSORPTION SPECTRA; CROSS-SECTIONS; NITROUS-OXIDE; BY-LINE; PRESSURE AB A theoretical model based on the energy-corrected sudden approximation is used in order to account for line-mixing effects in infrared Q branches of symmetric isotopomers of CO2, Its performance is demonstrated by comparisons with a large number (about 130) of CO2-N-2 and CO2-O-2 laboratory spectra recorded by several instrument setup: nine Q branches of different vibrational symmetries lying between 1 and 17 mu m are investigated in wide ranges of pressure (0.05-10 atm) and temperature 1200-300 K). The model is used to generate a set of suitable parameters and FORTRAN software (available by ftp for the calculation of the absorption within (CO2)-C-12-O-16, (CO2)-C-13-O-16, and (CO2)-C-12-O-18 infrared Q branches under atmospheric conditions, which can be easily included in existing radiance/transmission computer codes. Comparisons are made between many (about 280) computed atmospheric spectra and values measured using two different balloon-borne high-resolution Fourier transform instruments: transmission (solar occultation) as well as radiance (limb emission) measurements of seven Q branches between 13 and 17 mu m for a large range of atmospheric air masses and pressure/temperature conditions have been used, including the v(2), band of both (CO2)-C-12-O-16 and (CO2)-C-13-O-16, The results confirm the need to account for the effects of line-mixing and demonstrate the capability of the model to represent accurately the absorption in regions which are often used for temperature/pressure sounding of the atmosphere by space instruments. Finally, quantitative criteria assessing the validity of the widely used Rosenkranz first-order approximation are given, (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Paris 11, CNRS, Lab Phys Mol & Applicat, UPR 136, F-91405 Orsay, France. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Paris 06, URA 508 CNRS, Lab Spectrochim Mol, F-75252 Paris, France. Fac Univ Notre Dame Paix, Lab Spect Mol, B-5000 Namur, Belgium. Univ Rennes 1, UMR CNRS, Lab Phys Atomes Lasers Mol & Surfaces, F-35042 Rennes, France. Fac Sci & Tech, Mol Phys Lab, URA 772 CNRS, F-25030 Besancon, France. RP Hartmann, JM (reprint author), Univ Paris 11, CNRS, Lab Phys Mol & Applicat, UPR 136, Bat 350, F-91405 Orsay, France. EM jean-michel.hartmann@1pma.u-psud.fr RI Lacome, Nelly/A-7043-2008 NR 66 TC 44 Z9 47 U1 0 U2 4 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 JAN PY 1999 VL 61 IS 2 BP 153 EP 184 DI 10.1016/S0022-4073(97)00208-2 PG 32 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 142QC UT WOS:000077210800003 ER PT J AU Asher, GW Monfort, SL Wemmer, C AF Asher, GW Monfort, SL Wemmer, C TI Comparative reproductive function in cervids: implications for management of farm and zoo populations SO JOURNAL OF REPRODUCTION AND FERTILITY LA English DT Article; Proceedings Paper CT 5th International Symposium on Reproduction in Domestic Ruminants CY AUG 01-05, 1998 CL COLORADO SPRINGS, COLORADO SP InterAg, Intervet Int BV, Monsanto Co, Pharmacia & Upjohn Co, USDA, XY Inc, Select Sires ID DEER DAMA-DAMA; CERVUS-ELDI-THAMIN; MUNTJAC MUNTIACUS-REEVESI; FALLOW-DEER; RED DEER; SEASONAL-CHANGES; EMBRYO-TRANSFER; INTRAUTERINE INSEMINATION; ESTROUS SYNCHRONIZATION; ARTIFICIAL-INSEMINATION AB The cervids represent a complex assemblage of taxa characterized by extreme diversity in morphology, physiology, ecology and geographical distribution. Farmed species (for example red deer and fellow deer) are usually the common larger-bodied, gregarious and monotocous species that express marked reproductive seasonality in their temperate environment. Their commercial importance has facilitated considerable research into reproductive physiology and the development of assisted reproductive technologies (ART). In contrast, the remaining species, including many of tropical origin, show wide diversity in reproductive patterns, have generally received little scientific scrutiny, and include a number of endangered taxa that are reliant on ex situ conservation efforts (such as captive breeding) to ensure their survival. Domestication and ex situ management programmes have been associated with widespread translocation of various cervid species around the world, often placing the animals in environments that are not compatible with their evolved reproductive patterns. For example, the summer calving/lactation pattern of red deer, attuned to northern continental climatic patterns, is frequently misaligned with seasonal changes in feed availability in the Australasian pastoral environment. Similarly, seasonal or aseasonal calving patterns of tropical species translocated to temperate regions are usually associated with increased perinatal mortality of calves born in cool seasons. Conversely, temperate species in tropical zones may exhibit aberrant reproductive patterns in the absence of biologically significant photoperiod fluctuations. ARTs, which presently include artificial insemination, embryo transfer and in vitro embryo production, have potential application to the genetic management and population growth of various cervid species. Although application to some farmed cervid species is widespread, these technologies are rarely directly transferable from farmed to endangered species. Even within species, ART protocols developed successfully for one genotype (i.e. subspecies) may be ineffective in another (for example superovulation of red deer and wapiti). Therefore, application to genetic management of endangered species necessitates prior research into their reproductive patterns. This is often difficult because of the rarity of the animals, a lack of suitable handling facilities for the particular species, and the timid nature of the deer More recently, however, non-invasive reproductive profiling, based on remote collection and monitoring of excreted steroid metabolites, has facilitated such research. C1 AgRes, Invermay Agr Ctr, Mosgiel, New Zealand. Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA USA. RP Asher, GW (reprint author), AgRes, Invermay Agr Ctr, Private Bag 50034, Mosgiel, New Zealand. NR 53 TC 2 Z9 2 U1 0 U2 7 PU JOURNALS OF REPRODUCTION FERTILITY LTD PI CAMBRIDGE PA 22 NEWMARKET RD, CAMBRIDGE CB5 8DT, ENGLAND SN 0022-4251 J9 J REPROD FERTIL JI J. Reprod. Fertil. PY 1999 SU 54 BP 143 EP 156 PG 14 WC Reproductive Biology SC Reproductive Biology GA 254HF UT WOS:000083605300012 ER PT J AU Good, EM AF Good, EM TI The 'lovely' sound: Studies in historical music instruments in Germany and Japan with special attention to Old Nuremberg SO JOURNAL OF THE AMERICAN MUSICAL INSTRUMENT SOCIETY LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Good, EM (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER MUSIC INSTRUMENT SOC PI HEMPSTEAD PA MUSIC DEPT, EMILY LOWE HALL 112 HOFSTRA UNIVERSITY, HEMPSTEAD, NY 11362 USA SN 0362-3300 J9 J AM MUSIC INSTRUM S JI J. Am. Music. Instrum. Soc. PY 1999 VL 25 BP 161 EP 163 PG 3 WC Music SC Music GA 241JG UT WOS:000082878900014 ER PT J AU Briceno, RD Ramos, D Eberhard, WG AF Briceno, RD Ramos, D Eberhard, WG TI Aggressive behavior in medflies (Ceratitis capitata) and its modification by mass rearing (Diptera : Tephritidae) SO JOURNAL OF THE KANSAS ENTOMOLOGICAL SOCIETY LA English DT Article ID MEDITERRANEAN FRUIT-FLY; MATING-BEHAVIOR; FLIES DIPTERA AB Male and female Ceratitis capitata employ at least nine different behavior patterns during aggressive interactions that include possible visual, auditory, and tactile stimuli. Male flies of a 4.5 year old mass-reared strain were less aggressive in some respects than wild flies. C1 Univ Costa Rica, Escuela Biol, San Jose, Costa Rica. Inst Nacl Recursos Nat Renovables, Areas Protegidas, Corregimiento Ancon, Panama. Smithsonian Trop Res Inst, Balboa, Panama. RP Eberhard, WG (reprint author), Univ Costa Rica, Escuela Biol, Ciudad Univ, San Jose, Costa Rica. NR 18 TC 10 Z9 11 U1 0 U2 2 PU KANSAS ENTOMOLOGICAL SOC PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 USA SN 0022-8567 J9 J KANSAS ENTOMOL SOC JI J. Kans. Entomol. Soc. PD JAN PY 1999 VL 72 IS 1 BP 17 EP 27 PG 11 WC Entomology SC Entomology GA 278PN UT WOS:000084998300003 ER PT J AU Wcislo, WT AF Wcislo, WT TI Male territoriality and nesting behavior of Calliopsis hondurasicus cockerell (Hymenoptera : Andrenidae) SO JOURNAL OF THE KANSAS ENTOMOLOGICAL SOCIETY LA English DT Article ID BEES AB Calliopsis (Calliopsis) hondurasicus is the most widely distributed member of its genus, found from the southern United States throughout Mesoamerica, yet little has been recorded about its biology. Female nesting behavior and male territorial behavior are described for a population on the Pacific coast of central Panama. This population is protandrous, and bees become active at the start of the dry season in mid- to late-December, and activity ends in late January or early February. Males patrol areas where females emerge and later nest, and they defend territories to which they return repeatedly. Male-male contests involve a rapid spiraling-upward flight, often followed by physical aggression after the pair rumbles to the ground. Nearly all females are solitary nesters, but they dig nests within aggregations near other females. Details of nest architecture are given for comparative purposes. At this site females are restricted in their use of pollen, which may constrain the number of generations they produce per season. C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Wcislo, WT (reprint author), Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. EM WcisloW@tivoli.si.edu NR 15 TC 1 Z9 1 U1 1 U2 5 PU KANSAS ENTOMOLOGICAL SOC PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 USA SN 0022-8567 J9 J KANSAS ENTOMOL SOC JI J. Kans. Entomol. Soc. PD JAN PY 1999 VL 72 IS 1 BP 91 EP 98 PG 8 WC Entomology SC Entomology GA 278PN UT WOS:000084998300010 ER PT J AU Eberhard, WG AF Eberhard, WG TI Mating systems of sepsid flies and sexual behavior away from oviposition sites by Sepsis neocynipsea (Diptera : Sepsidae) SO JOURNAL OF THE KANSAS ENTOMOLOGICAL SOCIETY LA English DT Article AB Females of several sepsid flies usually mate at oviposition sites only after having emptied their ovaries of eggs, leaving unexplained how the first batch of eggs is fertilized. Repeated mating attempts at a feeding sire of female Sepsis neocynipsea suggest that copulations also occur at such sites, where sepsid behavior has seldom been observed. C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Costa Rica, Escuela Biol, San Jose, Costa Rica. RP Eberhard, WG (reprint author), Smithsonian Trop Res Inst, Balboa, Panama. NR 7 TC 7 Z9 7 U1 1 U2 6 PU KANSAS ENTOMOLOGICAL SOC PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 USA SN 0022-8567 J9 J KANSAS ENTOMOL SOC JI J. Kans. Entomol. Soc. PD JAN PY 1999 VL 72 IS 1 BP 129 EP 130 PG 2 WC Entomology SC Entomology GA 278PN UT WOS:000084998300014 ER PT J AU Remo, JL AF Remo, JL TI High-power-pulsed 1054-nm laser-induced shock pressure and momentum, and energy coupling to iron-nickel and stony meteorites SO LASER AND PARTICLE BEAMS LA English DT Article ID NEO AB Shock waves generated on eight meteorite and two Al targets by 5.4-5.6 J, 20-ns pulsed Nd:glass laser at 1054 nm generated peak pressures from 0.7 to 11 Gpa. The shock-induced particle velocities in the targets versus time was measured interferometrically. The target momentum coupling and mechanical momentum/energy coupling was highest for the Al. Among the meteorites the coupling was greatest for the Fe-Ni, which maintained physical integrity, and lowest for the stony meteorites, all of which disintegrated. Using particle velocity measurements, shock results are interpreted in terms of target fragmentation, inhomogeneity, and microstructural characteristics which are the dominant target parameters effecting energy and momentum coupling. Normalized values for the shocked material velocity and peak pressure in the targets compare favorably to similar experimental work on Al targets. Applications to modeling high-velocity meteoroid impact with planetary atmospheres, space debris remediation, and near-Earth object material interactions are discussed. C1 Harvard Smithsonian Ctr Astrophys, Div Planetary Sci, Cambridge, MA 02138 USA. RP Remo, JL (reprint author), Harvard Smithsonian Ctr Astrophys, Div Planetary Sci, Mail Stop 18, Cambridge, MA 02138 USA. NR 27 TC 14 Z9 14 U1 0 U2 1 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0263-0346 J9 LASER PART BEAMS JI Laser Part. Beams PY 1999 VL 17 IS 1 BP 25 EP 44 PG 20 WC Physics, Applied SC Physics GA 209UV UT WOS:000081068000003 ER PT B AU Huchra, JP AF Huchra, JP BE Davies, JI Impey, C Phillipps, S TI Low luminosity galaxies in large surveys SO LOW SURFACE BRIGHTNESS UNIVERSE: IAU COLLOQUIUM 171 SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT IAU Colloquium 171 on the Low Surface Brightness Universe CY JUL 05-10, 1998 CL CARDIFF, WALES SP Astron Soc Pacific, IAU ID CFA REDSHIFT SURVEY; CLUSTERS; FIELD; DENSITY AB The debate about the slope and amplitude of the galaxy luminosity function at the faint end is discussed w.r.t. faint galaxies in large surveys, in particular the second CfA (CfA2) and the Las Campanas (LCRS) redshift surveys. Large surveys are necessary to determine the statistics of rare objects or objects that can only be seen out to limited volumes. Both surveys show excesses of faint galaxies over Schechter function fits, but the parent sample for the LCRS survey generally does not contain large or low surface brightness galaxies which do appear in the CfA2 survey. The objects that comprise the relatively large excess of faint galaxies in the CfA2 survey are shown to be primarily of low surface brightness and late morphological type and are generally emission line galaxies. Galaxy samples constructed like the LCRS will generally always be deficient in low luminosity galaxies and thus are not useful for constraining the faint end of the galaxy luminosity function. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Huchra, JP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 30 TC 3 Z9 3 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-92-9 J9 ASTR SOC P PY 1999 VL 170 BP 45 EP 51 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN45E UT WOS:000081943500006 ER PT B AU Spaans, M AF Spaans, M BE Davies, JI Impey, C Phillipps, S TI The structure of the multi-phase ISM in low surface brightness galaxies SO LOW SURFACE BRIGHTNESS UNIVERSE: IAU COLLOQUIUM 171 SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT IAU Colloquium 171 on the Low Surface Brightness Universe CY JUL 05-10, 1998 CL CARDIFF, WALES SP Astron Soc Pacific, IAU ID SPIRAL GALAXIES; GAS; EVOLUTION; DISKS AB The multi-phase structure of the interstellar medium in low surface brightness galaxies is investigated and compared to observations. It is found that the ambient pressure and metallicity very strongly influence the abundances of molecular hydrogen and carbon monoxide. The emissivity of the latter is computed and found to agree naturally with the upper limits measured for low surface brightness galaxies. The implications for star formation efficiency and galaxy evolution are discussed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Spaans, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 19 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 1-886733-92-9 J9 ASTR SOC P PY 1999 VL 170 BP 237 EP 244 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN45E UT WOS:000081943500035 ER PT J AU Clark, ME Wolcott, TG Wolcott, DL Hines, AH AF Clark, ME Wolcott, TG Wolcott, DL Hines, AH TI Intraspecific interference among foraging blue crabs Callinectes sapidus: interactive effects of predator density and prey patch distribution SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE foraging; agonism; Callinectes sapidus; Macoma balthica; ultrasonic telemetry; Chesapeake Bay ID TRINGA-TOTANUS L; MICROHABITAT SELECTION; HAEMATOPUS-OSTRALEGUS; AGONISTIC BEHAVIOR; MYTILUS-EDULIS; LIMB AUTOTOMY; EXE ESTUARY; RATHBUN; RISK; OYSTERCATCHERS AB The interactive effects of predator density and prey distribution on the foraging behavior of an important estuarine predator were studied, at a fine temporal scale, using ultrasonic telemetry. The movement and agonistic activity of individual blue crabs Callinectes sapidus were monitored in large field enclosures, in which the density of crabs and the distribution of patches of bivalve prey Macoma balthica were varied. Agonism-related injury in blue crabs is common and may be quite costly. On a scale of days. blue crabs have been shown in previous studies to disperse, sometimes into prey-impoverished areas, in response to conspecific interference. On the scale of minutes to hours addressed in the present study, the density of predators and the distribution of their prey interacted to affect the foraging behavior and success of blue crabs. When only a single clam patch was available, blue crabs at high density interfered with each other's foraging by direct agonistic encounters, shown by an inverse correlation between agonistic activity and foraging success. Conversely, when prey were partitioned into 2 patches, blue crabs at high density apparently dispersed among the patches, thus minimizing direct agonistic clashes. Although crabs reduced the occurrence of agonistic encounters further than the 50 % attributable to their effectively halving their densities on each patch, they did not take refuge in the prey-impoverished areas between experimental patches for significant periods. Instead, they seemed to respond instantaneously to changing degree of risk by moving off the clam patch when another conspecific approached. 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, 5101 Belgrave Circle, Wilmington, NC 28403 USA. EM m_clark@iname.com RI Ross, Donald/F-7607-2012 OI Ross, Donald/0000-0002-8659-3833 NR 38 TC 63 Z9 64 U1 1 U2 4 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PY 1999 VL 178 BP 69 EP 78 DI 10.3354/meps178069 PG 10 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA 188ZD UT WOS:000079878600006 ER PT S AU Ivan, A Bruni, R Byun, K Everett, J Gorenstein, P Romaine, S AF Ivan, A Bruni, R Byun, K Everett, J Gorenstein, P Romaine, S BE Hepp, AF Prahl, JM Keith, TG Bailey, SG Fowler, JR TI Multilayer coatings for focussing hard X-ray telescopes SO MATERIALS IN SPACE-SCIENCE, TECHNOLOGY AND EXPLORATION SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Materials in Space-Science, Technology and Exploration at the 1998 MRS Fall Meeting CY NOV 29-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc, NASA, Elsevier Sci Ltd AB Several multilayer test coatings for hard X-ray telescopes were fabricated using DC magnetron sputtering. The process parameters were selected from a series of trials of single layer depositions. The samples were characterized using X-ray specular reflectivity scans, AFM, and cross-sectional TEM. Additional measurements (stylus profilometry, RES, and Auger analysis) were used in the optimization of the deposition rate and of the thin film properties (density, composition, surface/interface microroughness). The X-ray reflectivity scans showed that the combinations of reflector and spacer materials tested so far (W/Si and W/C) are suited for graded d-spacing multilayer coatings that present a constant reflectivity bandpass up to 70 keV. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ivan, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-457-2 J9 MATER RES SOC SYMP P PY 1999 VL 551 BP 297 EP 302 PG 6 WC Engineering, Aerospace; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BP33N UT WOS:000084731100035 ER PT B AU Harris, DE AF Harris, DE BE Rottgering, HJA Best, PN Lehnert, MD TI X-ray observations of radio galaxies SO MOST DISTANT RADIO GALAXIES LA English DT Proceedings Paper CT Colloquium on the Most Distant Radio Galaxies CY OCT 15-17, 1997 CL AMSTERDAM, NETHERLANDS SP Royal Netherlannds Academy of Arts & Sci ID CLUSTER GAS; CYGNUS-A; EMISSION; LOBES; M87; JET AB We review some of the ways that X-ray observations provide unique information on radio galaxies. Thermal bremsstrahlung X-ray emission provides detailed data on ambient densities and temperatures. These parameters in turn can be used for pressure balance calculations and can demonstrate how the ambient gas affects radio source structure. Additionally, many signatures of the interaction of radio jets and lobes with the hot gas are found in high resolution X-ray maps. Non-thermal X-ray emission from knots and hotspots of radio jets can give us constraints on the relativistic electron population for energies greater than that normally sampled in the radio (in the case of synchrotron emission) or can give us an independent estimate of the average magnetic field strength (if inverse Compton emission is the origin of the X-rays). From recent ROSAT HRI observations of 3C 390.3 and 3C 120, we show evidence that X-ray emission from knots and hotspots appears brightness; i.e. at the location of powerful shocks. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Harris, DE (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 30 TC 2 Z9 2 U1 0 U2 0 PU KONINKLIJKE AKAD WETENSCHAPPENVERHANDELINGEN, AFD NAT PI AMSTERDAM PA KLOVENIERSBURGWAL 29, P O BOX 19121, 1000 GC AMSTERDAM, NETHERLANDS BN 90-6984-238-6 PY 1999 BP 409 EP 423 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ84X UT WOS:000089817700033 ER PT J AU Yelavich, S AF Yelavich, S TI Picking on the French (Response to Stephen Weil's article on the art museum as palace) SO MUSEUM NEWS LA English DT Letter C1 Smithsonian Inst, Cooper Hewitt Natl Design Museum, New York, NY USA. RP Yelavich, S (reprint author), Smithsonian Inst, Cooper Hewitt Natl Design Museum, New York, NY USA. NR 1 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 JAN-FEB PY 1999 VL 78 IS 1 BP 7 EP + PG 0 WC Art SC Art GA 152HJ UT WOS:000077770600001 ER PT J AU Bay, A AF Bay, A TI Learning in and through art; A guide to discipline-based art education SO MUSEUM NEWS LA English DT Book Review C1 Smithsonian Inst, Smithsonian Office Educ, Washington, DC 20560 USA. RP Bay, A (reprint author), Smithsonian Inst, Smithsonian Office Educ, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 1 U2 3 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 JAN-FEB PY 1999 VL 78 IS 1 BP 23 EP 25 PG 3 WC Art SC Art GA 152HJ UT WOS:000077770600005 ER PT J AU Zotz, G Ziegler, H AF Zotz, G Ziegler, H TI Size-related differences in carbon isotope discrimination in the epiphytic orchid, Dimerandra emarginata SO NATURWISSENSCHAFTEN LA English DT Article ID PLANTS C1 Univ Wurzburg, Julius von Sachs Inst Biowissensch, Bot Garten, Lehrstuhl Bot 2, D-97082 Wurzburg, Germany. Smithsonian Trop Res Inst, Balboa, Panama. Tech Univ Munich, Inst Bot & Mikrobiol, Lehrstuhl Bot, D-80290 Munich, Germany. RP Zotz, G (reprint author), Univ Wurzburg, Julius von Sachs Inst Biowissensch, Bot Garten, Lehrstuhl Bot 2, Julius von Sachs Pl 3, D-97082 Wurzburg, Germany. NR 8 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0028-1042 J9 NATURWISSENSCHAFTEN JI Naturwissenschaften PD JAN PY 1999 VL 86 IS 1 BP 39 EP 40 DI 10.1007/s001140050566 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 161DR UT WOS:000078273800006 ER PT S AU Bolatto, AD Jackson, JM Wilson, CD Zhang, X AF Bolatto, AD Jackson, JM Wilson, CD Zhang, X BE Chu, YH Suntzeff, NB Hesser, JE Bohlender, DA TI Photodissociation regions in the Large Magellanic Cloud and IC 10 SO NEW VIEWS OF THE MAGELLANIC CLOUDS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 190th Symposium of the International-Astronomical-Union CY JUL 12-17, 1998 CL VICTORIA, CANADA SP Int Astron Union, Canadian Inst Theoret Astrophys, Univ Victoria, Dept Phys & Astron, Herzberg Inst Astrophys, Natl Res Council C1 Boston Univ, Dept Astron, Boston, MA 02215 USA. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Bolatto, AD (reprint author), Boston Univ, Dept Astron, 725 Commonwealth Ave, Boston, MA 02215 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 SN 0074-1809 BN 1-58381-021-8 J9 IAU SYMP PY 1999 IS 190 BP 128 EP 129 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU32Y UT WOS:000175704600032 ER PT S AU Sonneborn, G Pun, CSJ Garnavich, P Kirshner, R AF Sonneborn, G Pun, CSJ Garnavich, P Kirshner, R BE Chu, YH Suntzeff, NB Hesser, JE Bohlender, DA TI Birth of supernova remnant 1987A SO NEW VIEWS OF THE MAGELLANIC CLOUDS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 190th Symposium of the International-Astronomical-Union CY JUL 12-17, 1998 CL VICTORIA, CANADA SP Int Astron Union, Canadian Inst Theoret Astrophys, Univ Victoria, Dept Phys & Astron, Herzberg Inst Astrophys, Natl Res Council ID EMISSION AB Recent observations of SN 1987A made with HST/STIS show that the shock interaction of supernova debris with the innermost edge of the circumstellar ring has begun. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02139 USA. RP Sonneborn, G (reprint author), NASA, Goddard Space Flight Ctr, Code 681, Greenbelt, MD 20771 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 SN 0074-1809 BN 1-58381-021-8 J9 IAU SYMP PY 1999 IS 190 BP 136 EP 138 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU32Y UT WOS:000175704600036 ER PT B AU Comiskey, JA Dallmeier, F Alonso, A AF Comiskey, JA Dallmeier, F Alonso, A BE AguirreBravo, C Franco, CR TI Conservation and development approaches to integrated inventory and monitoring for adaptive management SO NORTH AMERICAN SCIENCE SYMPOSIUM: TOWARD A UNIFIED FRAMEWORK FOR INVENTORYING AND MONITORING FOREST ECOSYSTEM RESOURCES SE USDA FOREST SERVICE ROCKY MOUNTAIN RESEARCH STATION PROCEEDINGS LA English DT Proceedings Paper CT North American Science Symposium on Toward a Unified Framework for Inventorying and Monitoring Forest Ecosystem Resources CY NOV 01-06, 1998 CL GUADALAJARA, MEXICO SP USDA, Forest Serv, Inst Nacl Investigac Forestales & Agropecuarias, Natl Pk Serv, Univ Autonoma Guadalajara, Long Term Ecol Res, USDA, Gobierno Estado Jalisco, Canadian Forest Serv, Environm Canada, EMCO, Nat Resources Canada, US Dept Interior Geol Survey, SEMARNAP, SAGAR INIFAP AB In 1996 the Smithsonian's Monitoring and Assessment of Biodiversity Program (SI/MAB) and Shell Prospecting and Development B.V. Peru, in cooperation with Peruvian and international organizations launched a multi-disciplinary assessment and monitoring program for the Camisea region of Peru. The area is located east of the Andes along the Urubamba River. Located northwest of the Manu National Park, the area is considered one of the most species rich regions of the world. One of the largest gas reservoirs for South America is located in this biologically and culturally sensitive area. The project was designed to evaluate the impact of development on biodiversity following an adaptive management process-setting objectives, carrying out an assessment and monitoring plan for forest biodiversity, evaluation, and decisionmaking. The cyclical nature of the process was maintained through refining the objectives and management decisions based on the results. Thus, adaptive management gives managers the flexibility to adjust on-the-ground practices. This scheme of cooperation allowed more sound development decisions including the decision to avoid the creation of permanent roads, locating the gas processing plant in a biologically less sensitive area, the revegetation of disturbed sites with native species, and the use of underground pipelines. Six biological components (vegetation, mammals, arthropods, amphibian and reptiles, birds and aquatic systems) were inventoried in the initial assessment phase. The sites were selected to provide information on areas that would be potentially impacted by development. In addition, a strong local community program was established, and two workshops resulted in the implementation of a training program to build in-country capacity for biodiversity monitoring. A conceptual multi-disciplinary model far monitoring was developed to assess the impact of gas extraction, processing, and transport on the local biodiversity. The Camisea project is now coming to an end due to the Peruvian Government and Shell being unable to agree on the natural gas distribution, and subsequent monitoring phases will not continue. Nevertheless, we have had the opportunity to forge a relationship with industry that was beneficial for conservation. In addition, we feel that Shell's approach has now created a precedent that may well be incorporated into the industry by other companies. As conservation biologists we must be prepared to seek and forge other similar relationships that can benefit our natural environment. C1 Natl Museum Nat Hist, Smithsonian Inst Monitoring & Assessment Biodiver, Washington, DC 20560 USA. RP Comiskey, JA (reprint author), Natl Museum Nat Hist, Smithsonian Inst Monitoring & Assessment Biodiver, 10th & Constitut NW, Washington, DC 20560 USA. NR 16 TC 0 Z9 0 U1 0 U2 9 PU US DEPT AGR, FOREST SERV ROCKY MT FOREST & RANGE EXPTL STN PI FT COLLINS PA FT COLLINS, CO 80526 USA J9 US FOR SERV RMRS-P PY 1999 IS 12 BP 256 EP 260 PG 5 WC Ecology; Environmental Sciences; Forestry SC Environmental Sciences & Ecology; Forestry GA BP77R UT WOS:000086142400045 ER PT J AU Korpelainen, H Allen, NS AF Korpelainen, H Allen, NS TI Genetic variation in three species of epiphytic Octoblepharum (Leucobryaceae) SO NOVA HEDWIGIA LA English DT Article DE genetic variation; RA-PD; Octoblepharum; Leucobryaceae ID LIVERWORT; MOSSES AB The distribution of genetic variation as revealed by randomly amplified polymorphic DNA (RAPD) markers was examined in Octoblepharum albidum, O. cocuiense and O. pulvinatum in Panama. It was discovered that these mosses possess a considerable amount of genetic variation. Genetic distances between the three Octoblepharum species ranged from 0.315 to 0.340. Among O. albidum samples, which originated from different regions, the mean genetic distances between and within regions equalled 0.262 and 0.227, respectively. The analysis of molecular variance revealed that 72.8% of the variation was present within species and 27.2% among species. When analysing variation in O. albidum, 94.3% of the variation was found within regions and only 5.7% among regions. The observed pattern of genetic variation in Octoblepharum suggests that in most cases each population (colony) consists of one genet (clone) founded by a single colonizer. C1 Univ Helsinki, Dept Biosci, FIN-00014 Helsinki, Finland. Univ Panama, Dept Bot, Balboa, Panama. Smithsonian Trop Res Inst, Balboa, Panama. RP Korpelainen, H (reprint author), Univ Helsinki, Dept Biosci, POB 56, FIN-00014 Helsinki, Finland. OI Korpelainen, Helena/0000-0002-7046-6995 NR 30 TC 6 Z9 6 U1 1 U2 2 PU GEBRUDER BORNTRAEGER PI STUTTGART PA JOHANNESSTR 3A, D-70176 STUTTGART, GERMANY SN 0029-5035 J9 NOVA HEDWIGIA JI Nova Hedwigia PY 1999 VL 68 IS 3-4 BP 281 EP 290 PG 10 WC Plant Sciences SC Plant Sciences GA 208PK UT WOS:000081000100001 ER PT J AU Nevalainen, J Roos, M AF Nevalainen, J Roos, M TI A combined value of the Hubble constant SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 5th International Workshop on Topics in Astroparticle and Underground Physics (TAUP 97) CY SEP 07-11, 1997 CL LAQUILA, ITALY SP Inst Nazl Fisica Nucleare (INFN) ID CEPHEID DISTANCE SCALE; SPACE-TELESCOPE; DISCOVERY; M100 AB We combine measurements of the Hubble constant in M100, M96, NGC 5253 and IC 4182 including the correction due to the metallicity dependence of the period-luminosity relation of Cepheids, as determined by Beaulieu et al. [1] and Sasselov et al. [2]. We pay special attention to error correlations. C1 Univ Helsinki Observ, FIN-00014 Helsinki, Finland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 01238 USA. Univ Helsinki, Dept Phys, Div High Energy Phys, FIN-00014 Helsinki, Finland. RP Nevalainen, J (reprint author), Univ Helsinki Observ, POB 14, FIN-00014 Helsinki, Finland. NR 12 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 70 BP 123 EP 125 DI 10.1016/S0920-5632(98)00402-2 PG 3 WC Physics, Particles & Fields SC Physics GA 122EQ UT WOS:000076059300021 ER PT J AU Lamb, FK Miller, MC Psaltis, D AF Lamb, FK Miller, MC Psaltis, D TI Rapid X-ray variability of neutron stars in low-mass binary systems SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Symposium on the Active X-ray Sky CY OCT 21-24, 1996 CL ROME, ITALY ID QUASI-PERIODIC OSCILLATIONS; RELATIVISTIC STARS; DISK ACCRETION; GX5-1; X-1 AB The dramatic discovery with the Rossi X-Ray Timing Explorer satellite of remarkably coherent similar to 300-1200 Hz oscillations in the X-ray brightness of some sixteen neutron stars in low-mass binary systems has spurred theoretical modeling of these oscillations and investigation of their implications for the neutron stars and accretion flows in these systems. High-frequency oscillations are observed both during thermonuclear X-ray bursts and during intervals of accretion-powered emission and appear to be a characteristic feature of disk-accreting neutron stars with weak magnetic fields. In this review we focus on the high-frequency quasi-periodic oscillations (QPOs) seen in the accretion-powered emission. We first summarize the key properties of these kilohertz QPOs and then describe briefly the models that have been proposed to explain them. The existing evidence strongly favors beat-frequency models. We mention several of the difficulties encountered in applying the magnetospheric beat-frequency model to the kilohertz QPOs. The most fully developed and successful model is the sonic-point beat-frequency model. We describe the work on this model in some detail. We then discuss observations that could help to distinguish between models. We conclude by noting some of the ways in which study of the kilohertz QPOs may advance our understanding of dense matter and strong gravitational fields. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Lamb, FK (reprint author), Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. NR 40 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 69 IS 1-3 BP 113 EP 122 DI 10.1016/S0920-5632(98)00193-5 PG 10 WC Physics, Particles & Fields SC Physics GA 121WM UT WOS:000076038800021 ER PT J AU Miller, MC Lamb, FK Psaltis, D AF Miller, MC Lamb, FK Psaltis, D TI Constraints on the equation of state of neutron star matter from observations of kilohertz QPOs SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Symposium on the Active X-ray Sky CY OCT 21-24, 1996 CL ROME, ITALY ID PULSAR AB The frequencies of the highest-frequency kilohertz QPOs recently discovered in some sixteen neutron stars in low-mass X-ray binary systems are most likely the orbital frequencies of gas in Keplerian orbit around these neutron stars. If so, these QPOs provide tight upper bounds on the masses and radii of these neutron stars and important new constraints on the equation of state of neutron star matter. If the frequency of a kilohertz QPO can be established as the orbital frequency of gas at the innermost stable circular orbit, this would confirm one of the key predictions of general relativity in the strong-gravity regime. If the spin frequency of the neutron star can also be determined, the frequency of the QPO would fix the mass of the neutron star for each assumed equation of state. Here we show how to derive mass and radius bounds, using the kilohertz QPOs, for nonrotating and slowly rotating stars, and discuss how these bounds are affected by rapid stellar rotation and radial radiation forces. We also describe observational results that would be strong evidence for the presence of an innermost stable circular orbit. No such strong evidence is present in current data, but future prospects are excellent. C1 Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Miller, MC (reprint author), Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. NR 20 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 69 IS 1-3 BP 123 EP 128 PG 6 WC Physics, Particles & Fields SC Physics GA 121WM UT WOS:000076038800022 ER PT J AU Boirin, L Olive, JF Barret, D Grindlay, JE Swank, JH Smale, AP AF Boirin, L Olive, JF Barret, D Grindlay, JE Swank, JH Smale, AP TI RXTE/PCA observation of the X-ray burster 1E1724-3045 - Aperiodic variability of the persistent emission SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Symposium on the Active X-ray Sky CY OCT 21-24, 1996 CL ROME, ITALY AB We report on the November 1996 Rossi X-ray Timing Explorer (RXTE) observation of the X-ray burster 1E1724-3045 with the Proportional Counter Array (PCA). The persistent X-ray emission shows a high level of noise variability, the so-called High Frequency Noise (HFN), with a fractional Root heart Squared (RMS) of similar to 25% in the 2 x 10(-3) - 40 Hz range (2-20 keV). The Fourier Power Density Spectrum (PDS) can be modeled in terms of the sum of two "shot noise" components with two characteristic timescales of BSO and 16 msec. The PDS contains also a third component: a broad Quasi Periodic Oscillation-like (QPO) feature centered at 0.8 Hz. Neither the shot timescales nor the QPO frequency do not vary with energy, whereas the integrated RMS of all three components shows a positive correlation. In addition, in the 2-20 keV energy band, we found significant evidence for a high frequency component which shows up to 500 Hz in he PDS. In terms of the shot noise model, a Lorentzian fit of this component implies a shot duration of about 1.4 ms. The reality of this component has been tested with the help of simulations. Our observation of the burster 1E1724-3045 reveals timing properties, such as low frequency QPO and high level of RMS for the HFN, also displayed by Black Hole Candidates (BHC). C1 Ctr Etud Spatiale Rayonnements, CNRS, UPS, F-31029 Toulouse, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Boirin, L (reprint author), Ctr Etud Spatiale Rayonnements, CNRS, UPS, F-31029 Toulouse, France. RI Swank, Jean/F-2693-2012 NR 9 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 69 IS 1-3 BP 245 EP 248 DI 10.1016/S0920-5632(98)00218-7 PG 4 WC Physics, Particles & Fields SC Physics GA 121WM UT WOS:000076038800046 ER PT J AU Otterbein, K Hardcastle, MJ Wagner, SJ Worrall, DR AF Otterbein, K Hardcastle, MJ Wagner, SJ Worrall, DR TI Intensive monitoring of the strongly variable BL Lac S5 0716+714 SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Symposium on the Active X-ray Sky CY OCT 21-24, 1996 CL ROME, ITALY ID SPECTRUM RADIO-SOURCES; COMPLETE SAMPLE; FLAT AB The BL Lac object S5 07161+714 was monitored during a multifrequency campaign in 1996. Preliminary analysis of the optical, ROSAT and RXTE data are presented. Strong variability on short time scales was observed. The data suggest an interpretation within a multi-component model. C1 Landessternewarte Heidelberg Konigstuhl, D-69117 Heidelberg, Germany. Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Otterbein, K (reprint author), Landessternewarte Heidelberg Konigstuhl, D-69117 Heidelberg, Germany. RI Hardcastle, Martin/E-2264-2012 OI Hardcastle, Martin/0000-0003-4223-1117 NR 12 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 69 IS 1-3 BP 415 EP 418 DI 10.1016/S0920-5632(98)00252-7 PG 4 WC Physics, Particles & Fields SC Physics GA 121WM UT WOS:000076038800080 ER PT J AU Uttley, P McHardy, IM Papadakis, IE Cagnoni, I Fruscione, A AF Uttley, P McHardy, IM Papadakis, IE Cagnoni, I Fruscione, A TI X-ray spectral variability of NGC 4051 SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Symposium on the Active X-ray Sky CY OCT 21-24, 1996 CL ROME, ITALY ID GALAXY NGC-4051; EMISSION AB We present results from RXTE and EUVE observations of the bright, highly variable Seyfert 1 galaxy, NGC 4051. Spectral analysis of RXTE data obtained from monitoring observations and a 'long look' (similar to 75 ksec) shows: a) strong spectral slope variability in the medium energy X-ray band, b) low energy absorption which increases with decreasing source flux, c) an similar to 6 keV iron line which remains effectively constant despite continuum flux changes in excess of factor la. Simultaneous RXTE and EUVE observations confirm the slope variability and also imply the presence of a constant 'soft-excess'. We discuss the implications of these results for models of iron Line and soft-excess production in NCTC 4051. C1 Univ Southampton, Southampton SO17 1BJ, Hants, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Uttley, P (reprint author), Univ Southampton, Southampton SO17 1BJ, Hants, England. NR 9 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 69 IS 1-3 BP 490 EP 495 DI 10.1016/S0920-5632(98)00268-0 PG 6 WC Physics, Particles & Fields SC Physics GA 121WM UT WOS:000076038800096 ER PT J AU Stirpe, GM Wilkes, BJ Comastri, A Mathur, S O'Brien, PT AF Stirpe, GM Wilkes, BJ Comastri, A Mathur, S O'Brien, PT TI BeppoSAX observations of the Seyfert 1 galaxy NGC 3516 SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Symposium on the Active X-ray Sky CY OCT 21-24, 1996 CL ROME, ITALY ID NGC-3516; EMISSION AB We present the results of two observations of the bright Seyfert 1 galaxy NGC 3516, obtained with BeppoSAX in 1996 November and 1997 March. Useful signal is detected between 0.2 and 60 keV, allowing for the first time the simultaneous observation of all main spectral features. The source was brighter by a factor 2 at the second epoch of observation. Both spectra present a strong Fe K alpha line, and a reflection hump at high energy. An absorption edge at 0.8 keV is visible in the later spectrum, but not in the earlier one, indicating that this feature is strongly variable. C1 Osservatorio Astron Bologna, I-40126 Bologna, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. RP Stirpe, GM (reprint author), Osservatorio Astron Bologna, Via Zamboni 33, I-40126 Bologna, Italy. RI Stirpe, Giovanna/O-9393-2015; Comastri, Andrea/O-9543-2015 OI Wilkes, Belinda/0000-0003-1809-2364; Stirpe, Giovanna/0000-0002-3702-8731; Comastri, Andrea/0000-0003-3451-9970 NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 69 IS 1-3 BP 505 EP 508 DI 10.1016/S0920-5632(98)00271-0 PG 4 WC Physics, Particles & Fields SC Physics GA 121WM UT WOS:000076038800099 ER PT J AU Hudec, R Pina, L Inneman, A Gorenstein, P Rezek, T AF Hudec, R Pina, L Inneman, A Gorenstein, P Rezek, T TI Wide field X-ray telescopes: Detecting X-ray transients/afterglows related to Gamma Ray Bursts SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Symposium on the Active X-ray Sky CY OCT 21-24, 1996 CL ROME, ITALY AB The recent discovery of X-ray afterglows of GRBs opens the possibility of analyses of GRBs by their X-ray detections. However, imaging X-ray telescopes in current use mostly hat-e limited field of view. Alternative X-ray optics geometries achieving very large fields of view have been theoretically suggested in the 70ies but not constructed and used so far. We review the geometries and basic properties of the wide-field X-ray optical systems based on one- and two-dimensional lobster-eye geometry and suggest technologies for their development and construction. First results of the development of double replicated X-ray reflecting fiats for use in one-dimensional X-ray optics of lobster eye type are presented and discussed. Optimum strategy for locating GRBs upon their X-ray counterparts is also presented and discussed. C1 Acad Sci Czech Republ, Inst Astron, Observ Ondrejov, CS-25165 Ondrejov, Czech Republic. Czech Tech Univ, Fac Nucl Engn, CR-16635 Prague, Czech Republic. Czech Tech Univ, Fac Mech Engn, Dept Precis Mech & Opt, CR-16635 Prague, Czech Republic. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hudec, R (reprint author), Acad Sci Czech Republ, Inst Astron, Observ Ondrejov, CS-25165 Ondrejov, Czech Republic. RI Hudec, Rene/G-9018-2014 NR 8 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JAN PY 1999 VL 69 IS 1-3 BP 716 EP 719 DI 10.1016/S0920-5632(98)00286-2 PG 4 WC Physics, Particles & Fields SC Physics GA 121WM UT WOS:000076038800140 ER PT B AU Jordan, TE Whigham, DF Hofmockel, K Gerber, N AF Jordan, TE Whigham, DF Hofmockel, K Gerber, N BE Vymazal, J TI Restored wetlands in crop fields control nutrient runoff SO NUTRIENT CYCLING AND RETENTION IN NATURAL AND CONSTRUCTED WETLANDS LA English DT Proceedings Paper CT Workshop on Nutrient Cycling and Retention in Natural and Constructed Wetlands CY SEP 03-06, 1997 CL TREBON, CZECH REPUBLIC SP Acad Sci Czech Republ, Botan Inst ID CHESAPEAKE BAY; PHOSPHORUS RETENTION; PHYTOPLANKTON; DISCHARGES; WATERSHEDS; MARSHES; FATE; FLUX C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Jordan, TE (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. NR 34 TC 13 Z9 13 U1 0 U2 4 PU BACKHUYS PUBLISHERS PI LEIDEN PA PO BOX 321, 2300 AH LEIDEN, NETHERLANDS BN 90-5782-022-6 PY 1999 BP 49 EP 60 PG 12 WC Plant Sciences; Ecology SC Plant Sciences; Environmental Sciences & Ecology GA BN04F UT WOS:000080481300005 ER PT J AU Yonemura, A AF Yonemura, A TI Decoration and representation in Japanese lacquer SO ORIENTAL ART LA English DT Article C1 Smithsonian Inst, Arthur M Sackler Gallery, Washington, DC 20560 USA. RP Yonemura, A (reprint author), Smithsonian Inst, Arthur M Sackler Gallery, Washington, DC 20560 USA. NR 9 TC 0 Z9 0 U1 1 U2 2 PU ORIENTAL ART MAGAZINE LTD PI RICHMOND PA 12 ENNERDALE RD, RICHMOND, SURREY, ENGLAND TW9 3PG SN 0030-5278 J9 ORIENTAL ART JI Orient. Art PY 1999 VL 45 IS 3 BP 16 EP 22 PG 7 WC Art; Asian Studies SC Art; Asian Studies GA 252XR UT WOS:000083528000002 ER PT S AU Myers, PC AF Myers, PC BE Lada, CJ Kylafis, ND TI Physical conditions in nearby molecular clouds SO ORIGIN OF STARS AND PLANETARY SYSTEMS SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT 2nd NATO Advanced Study Institute on Star Formation and Early Stellar Evolution CY MAY 24-JUN 05, 1998 CL IRAKLION, GREECE SP NATO Sci Affairs Div, Univ Crete ID INTER-STELLAR CLOUDS; DENSE CORES; STAR-FORMATION; DARK CLOUDS; AMBIPOLAR DIFFUSION; INTERSTELLAR CLOUDS; MAGNETIC BRAKING; CARBON-MONOXIDE; AMMONIA CLUMPS; LINE FORMATION C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Myers, PC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM pmyers@cfa.harvard.edu NR 93 TC 24 Z9 24 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-5908-9 J9 NATO ADV SCI I C-MAT PY 1999 VL 540 BP 67 EP 95 PG 29 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP44K UT WOS:000085158800003 ER PT S AU Lada, CJ AF Lada, CJ BE Lada, CJ Kylafis, ND TI The formation of low mass stars - An observational overview SO ORIGIN OF STARS AND PLANETARY SYSTEMS SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT 2nd NATO Advanced Study Institute on Star Formation and Early Stellar Evolution CY MAY 24-JUN 05, 1998 CL IRAKLION, GREECE SP NATO Sci Affairs Div, Univ Crete ID YOUNG STELLAR OBJECTS; T-TAURI STARS; SPECTRAL ENERGY-DISTRIBUTIONS; INFRARED LUMINOSITY FUNCTIONS; AURIGA MOLECULAR CLOUD; MAIN-SEQUENCE STARS; SOLAR-TYPE STARS; DENSE CORES; CIRCUMSTELLAR DISKS; EMBEDDED CLUSTERS C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Lada, CJ (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. EM clada@bok.harvard.edu; clada@bok.harvard.edu NR 138 TC 42 Z9 42 U1 0 U2 3 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-5908-9 J9 NATO ADV SCI I C-MAT PY 1999 VL 540 BP 143 EP 191 PG 49 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP44K UT WOS:000085158800005 ER PT S AU Kenyon, SJ AF Kenyon, SJ BE Lada, CJ Kylafis, ND TI Accretion disks and eruptive phenomena SO ORIGIN OF STARS AND PLANETARY SYSTEMS SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT 2nd NATO Advanced Study Institute on Star Formation and Early Stellar Evolution CY MAY 24-JUN 05, 1998 CL IRAKLION, GREECE SP NATO Sci Affairs Div, Univ Crete ID T-TAURI STARS; FU-ORIONIS STARS; Z-CANIS-MAJORIS; SPECTRAL ENERGY-DISTRIBUTIONS; ANGULAR-MOMENTUM TRANSPORT; YOUNG STELLAR OBJECTS; LOCAL SHEAR INSTABILITY; WEAKLY MAGNETIZED DISKS; STEADY-STATE STRUCTURES; AURIGA MOLECULAR CLOUD C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Kenyon, SJ (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 190 TC 8 Z9 8 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-5908-9 J9 NATO ADV SCI I C-MAT PY 1999 VL 540 BP 613 EP 642 PG 30 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP44K UT WOS:000085158800018 ER PT J AU Gingerich, O AF Gingerich, O TI The Copernican quinquecentennial and its predecessors - Historical insights and national agendas SO OSIRIS LA English DT Article 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 39 TC 6 Z9 6 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0369-7827 J9 OSIRIS JI Osiris PY 1999 VL 14 BP 37 EP 60 PG 24 WC History & Philosophy Of Science SC History & Philosophy of Science GA 337GM UT WOS:000088349100003 ER PT J AU Schuster, BG Jackson, JE Obijiofor, CN Okunji, CO Milhous, W Losos, E Ayafor, JF Iwu, MM AF Schuster, BG Jackson, JE Obijiofor, CN Okunji, CO Milhous, W Losos, E Ayafor, JF Iwu, MM TI Drug development and conservation of biodiversity in West and Central Africa: A model for collaboration with indigenous people SO PHARMACEUTICAL BIOLOGY LA English DT Article DE Africa; ICBG; drug development; malaria; leishmaniasis; antiviral; natural products; sustainable development; biodiversity conservation; intellectual property rights AB The main focus of the African ICBG project is the establishment of an integrated program for the discovery of biologically active plants for drug development and biodiversity conservation, and at the same time ensure that local communities and source countries derive maximum benefits for their biological resources and their intellectual contribution. Although the project has three main sub-themes (biodiversity conservation, sustainable development and drug discovery), integration was emphasized from the conception of the program and has remained a fundamental point in the execution of various projects under this program. As a result. the African ICBG program differs in many ways from similar projects elsewhere. The African ICBG is a collaboration of the Waiter Reed Army Institute of Research, Washington, DC (WRAIR), Bioresources Development and Conservation programme (BDCP), the Smithsonian Tropical Research Institute. and nine other institutions in Cameroon. Nigeria and the United States of America. Scientists front the participating developing countries are involved in all aspects of the program so that information, principles and procedures developed during this work will be internalized in Africa and extended beyond the duration of the proposed project. The drug discovery component has yielded many lead compounds with potential for the treatment of malaria, leishmaniasis, trypanosomiasis, trichomonas, opportunistic infections, AIDS and other viral infections. Activity of some of the compounds is being optimized through chemical modifications. C1 Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Washington, DC 20307 USA. Bioresources Dev & Conservat Programme, Silver Spring, MD USA. Smithsonian Inst, Ctr Trop Forest Sci, Washington, DC 20560 USA. Univ Dschang, Fac Sci, Dschang, Cameroon. Bioresources Dev & Conservat Programme, Nsukka, Nigeria. RP Schuster, BG (reprint author), Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Washington, DC 20307 USA. NR 10 TC 4 Z9 5 U1 1 U2 6 PU SWETS ZEITLINGER PUBLISHERS PI LISSE PA P O BOX 825, 2160 SZ LISSE, NETHERLANDS SN 1388-0209 J9 PHARM BIOL JI Pharm. Biol. PY 1999 VL 37 SU S BP 84 EP 99 DI 10.1076/1388-0209(200010)37:SUP;1-W;FT084 PG 16 WC Plant Sciences; Medical Laboratory Technology; Pharmacology & Pharmacy SC Plant Sciences; Medical Laboratory Technology; Pharmacology & Pharmacy GA 375MC UT WOS:000165402200007 ER PT J AU Kursar, TA Capson, TL Coley, PD Corley, DG Gupta, MB Harrison, LA Ortega-Barria, E Windsor, DM AF Kursar, TA Capson, TL Coley, PD Corley, DG Gupta, MB Harrison, LA Ortega-Barria, E Windsor, DM TI Ecologically guided bioprospecting in Panama SO PHARMACEUTICAL BIOLOGY LA English DT Article DE conservation; intellectual property; plants; beetles; endophytic fungi; Trypanosoma; leishmaniasis; malaria; cancer; HIV ID ENDOPHYTIC FUNGI; DRUG DISCOVERY; PLANT; HERBIVORY; RESISTANCE; DIVERSITY; PROGRAM; PROTEIN; LEAVES; FOREST AB This ICBG program links the discovery of drugs and genes for agriculture with biodiversity conservation. We employ a combination of approaches including technology transfer to panama, the development of Panama's scientific infrastructure for drug and gene discovery, the training of Panamanian scientists, the involvement of seven Panamanian laboratories in research, and the equitable sharing of revenues among a diversity Of Panamanian institutions. In Panama, we will conduct assays to detect activity against cancer HIV, malaria, Trypanosoma cruzi (the causative agent of Chagas' disease), leishmaniasis and agricultural pests. Monsanto Company Mill also test samples in their pharmaceutical and agricultural screens. provide NMR spectra, as well as provide training for Panamanian scientists. Any royalties or milestones received from commercialization will be shared among (i) a find of the Panamanian government that supports the national park system, (ii) a Panamanian foundation funding conservation and sustainable development projects, and (iii) the three collaborating scientific institutions. In collaboration with Conservation International, we will help indigenous communities record their ethnobotanical traditions and provide educational and internship programs for indigenous participants. For collecting biological materials, we employ the use of novel ecological criteria to increase the probability of discovering active compounds. Our data suggest that the application of Ecological principles to the collecting of plants, insects and fungi will provide samples with greater activity in biological assays than samples collected at random. Using Ecological insight for collection, promoting infrastructure development, and returning benefits to a broad range of institutions will have maximal impact on conservation both in the short- and long-term. C1 Univ Utah, Dept Biol, Salt Lake City, UT 84112 USA. Smithsonian Trop Res Inst, Balboa, Panama. Monsanto Co, St Louis, MO USA. Univ Panama, Coll Pharm, Panama City, Panama. Gorgas Mem Inst Hlth Res, Panama City, Panama. RP Kursar, TA (reprint author), Univ Utah, Dept Biol, 257 South 1400 East, Salt Lake City, UT 84112 USA. OI Gupta, Mahabir/0000-0002-9302-7864 NR 59 TC 23 Z9 23 U1 2 U2 20 PU SWETS ZEITLINGER PUBLISHERS PI LISSE PA P O BOX 825, 2160 SZ LISSE, NETHERLANDS SN 1388-0209 J9 PHARM BIOL JI Pharm. Biol. PY 1999 VL 37 SU S BP 114 EP 126 DI 10.1076/1388-0209(200010)37:SUP;1-W;FT114 PG 13 WC Plant Sciences; Medical Laboratory Technology; Pharmacology & Pharmacy SC Plant Sciences; Medical Laboratory Technology; Pharmacology & Pharmacy GA 375MC UT WOS:000165402200009 ER PT J AU Wells, JC Segev, B Eichler, J AF Wells, JC Segev, B Eichler, J TI Asymptotic channels and gauge transformations of the time-dependent Dirac equation for extremely relativistic heavy-ion collisions SO PHYSICAL REVIEW A LA English DT Article ID POSITRON PAIR PRODUCTION; IMPACT-PARAMETER DEPENDENCE; STRONG EXTERNAL FIELDS; COULOMB COLLISIONS; ELECTRON-CAPTURE; SULFUR IONS; ELECTROMAGNETIC-FIELDS; ATOMIC-COLLISIONS; CHARGE-TRANSFER; FIXED TARGETS AB We discuss the two-center, time-dependent Dirac equation describing the dynamics of an electron during a peripheral, relativistic heavy-ion collision at extreme energies. We derive a factored form, which is exact in the high-energy limit, for the asymptotic channel solutions of the Dirac equation, and elucidate their close connection with gauge transformations which transform the dynamics into a representation in which the interaction between the electron and a distant ion is of short range. We describe the implications of this relationship for solving the time-dependent Dirac equation for extremely relativistic collisions. [S1050-2947(99)03801-9]. C1 Oak Ridge Natl Lab, Ctr Computat Sci, Oak Ridge, TN 37831 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, Bereich Theoret Phys, D-14109 Berlin, Germany. Free Univ Berlin, Fachbereich Phys, D-14195 Berlin, Germany. RP Wells, JC (reprint author), Oak Ridge Natl Lab, Ctr Computat Sci, Oak Ridge, TN 37831 USA. RI Wells, Jack/D-3675-2016 OI Wells, Jack/0000-0002-5083-3030 NR 45 TC 6 Z9 6 U1 0 U2 1 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 JAN PY 1999 VL 59 IS 1 BP 346 EP 357 DI 10.1103/PhysRevA.59.346 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 158JD UT WOS:000078111500052 ER PT J AU Marinescu, M Sadeghpour, HR AF Marinescu, M Sadeghpour, HR TI Long-range potentials for two-species alkali-metal atoms SO PHYSICAL REVIEW A LA English DT Article ID BOSE-EINSTEIN CONDENSATION; DISPERSION COEFFICIENTS; STATES; NA; POLARIZABILITIES; SCATTERING; STABILITY; SYSTEMS; FORCES; DIMERS AB We address a growing interest in trapping and cooling of mixed-species alkali-metal atoms. Long-range coefficients that arise in the multipole expansion of molecular potentials for unlike alkali-metal dimers are calculated. The coefficients for the heteronuclear alkali-metal dimers corresponding to different molecular symmetries that separate to nS-n'S,nS-n'P,nS-n'D, and nP-n'P atomic levels are computed with high precision. We consider cases where in the infinite separation Limit, one atom is in the ground state and the other is in one of the lowest S, P, and D excited states and both atoms are in their lowest excited P states. We find the long-range potentials for Rb(5S)-Cs(6S), Rb(6S)-Cs(6S), K(4S)-Rb(5P) (1,3)Sigma, K(4P)-Cs(6P) (1,3)Sigma, and Rb(5S)-Na(3D) (1,3)Sigma molecules to be the most attractive. The K(4S)-Rb(SP) dimer represents the best candidate molecule for ultracold photoassociative spectroscopy. We also find the K(4P)-Cs(6P) and Rb(SS)-K(4P) dimers to form, respectively, the most attractive and the most repulsive long-range potentials. The present calculation is in good agreement with experimentally determined value for the 1/R-6 van der Waals coefficient for the interaction between Cs(6S) and Li(2P) atoms. [S1050-2947(99)07101-2]. C1 Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Sadeghpour, HR (reprint author), Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. EM hsadeghpour@cfa.harvard.edu NR 34 TC 110 Z9 112 U1 1 U2 6 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 JAN PY 1999 VL 59 IS 1 BP 390 EP 404 DI 10.1103/PhysRevA.59.390 PG 15 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 158JD UT WOS:000078111500057 ER PT J AU Noel, S Bovensmann, H Burrows, JP Frerick, J Chance, KV Goede, AHP AF Noel, S Bovensmann, H Burrows, JP Frerick, J Chance, KV Goede, AHP TI Global atmospheric monitoring with SCIAMACHY SO PHYSICS AND CHEMISTRY OF THE EARTH PART C-SOLAR-TERRESTIAL AND PLANETARY SCIENCE LA English DT Article ID OZONE; ABSORPTION AB SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) is a space based spectrometer designed to measure sunlight transmitted, reflected and scattered by the Earth atmosphere or surface. It is a contribution to the Envisat-1 satellite to be launched in late 1999. SCIAMACHY measurements will provide amounts and distribution of O-3, BrO, OClO, ClO, SO2, H2CO, NO2, CO, CO2, CH4, H2O, N2O, pressure, temperature, aerosol, radiation, cloud cover and cloud top height from atmospheric measurements in nadir, limb and occultation geometry. By the combination of the near simultaneous limb and nadir observations SCIAMACHY is one of a limited number of instruments which is able to detect tropospheric column amounts of O-3, NO2, CO, CH4, H2O, N2O, SO2, H2CO, and BrO down to the planetary boundary layer under cloud free conditions. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Bremen, Inst Environm Phys, FB 1, D-28334 Bremen, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. SRON Ruimteonderzoek, NL-3584 Utrecht, Netherlands. RP Noel, S (reprint author), Univ Bremen, Inst Environm Phys, FB 1, D-28334 Bremen, Germany. RI Bovensmann, Heinrich/P-4135-2016; Burrows, John/B-6199-2014; OI Bovensmann, Heinrich/0000-0001-8882-4108; Burrows, John/0000-0002-6821-5580; Chance, Kelly/0000-0002-7339-7577 NR 18 TC 15 Z9 16 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1917 J9 PHYS CHEM EARTH PT C JI Phys. Chem. Earth Pt. C-Solar-Terr. Planet. Sci. PY 1999 VL 24 IS 5 BP 427 EP 434 DI 10.1016/S1464-1917(99)00066-5 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 250FX UT WOS:000083379300001 ER PT J AU Sanmartin, JR Estes, RD AF Sanmartin, JR Estes, RD TI The orbital-motion-limited regime of cylindrical Langmuir probes SO PHYSICS OF PLASMAS LA English DT Article ID COLLECTION; SATELLITE; TETHERS AB An asymptotic analysis of electron collection at high bias Phi(p) serves to determine the domain of validity of the orbital-motion-limited (OML) regime of cylindrical Langmuir probes, which is basic for the workings of conductive bare tethers. The radius of a wire collecting OML current in an unmagnetized plasma at rest cannot exceed a value, R-max, which is found to exhibit a minimum as a function of Phi(p); at Phi(p) values of interest, R-max is already increasing and is larger than the electron Debye length lambda(De). The breakdown of the regime relates to conditions far from the probe, at electron energies comparable to the ion thermal energy, kT(i); R-max is found to increase with T-i. It is also found that (1) the maximum width of a thin tape, if used instead of a wire, is 4R(max); (2) the electron thermal gyroradius must be larger than both R and lambda(De) for magnetic effects to be negligible; and (3) conditions applying to the tether case are such that trapped- orbit effects are negligible. (C) 1999 American Institute of Physics. [S1070-664X(99)03801-X]. C1 Univ Politecn Madrid, ETSI Aeronaut, E-28040 Madrid, Spain. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Sanmartin, JR (reprint author), Univ Politecn Madrid, ETSI Aeronaut, E-28040 Madrid, Spain. EM jrs@faia.upm.es NR 19 TC 67 Z9 67 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 1999 VL 6 IS 1 BP 395 EP 405 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 152TD UT WOS:000077792100044 ER PT J AU Kamoun, P Campbell, D Pettengill, G Shapiro, I AF Kamoun, P Campbell, D Pettengill, G Shapiro, I TI Radar observations of three comets and detection of echoes from one: P/Grigg-Skjellerup SO PLANETARY AND SPACE SCIENCE LA English DT Article ID NUCLEUS; ENCKE AB Radar echoes from the nucleus of the short-period comet Grigg-Skjellerup were obtained using the 12.6 cm wavelength radar of the Arecibo Observatory during the apparition of 20 May-2 June 1982. Dual circularly-polarized receiving channels were employed. The receiving mode orthogonally polarized to the transmission yielded an echo equal to nearly 10 times the standard deviation of the accompanying noise; no echo was detected in the polarization of the same sense as transmitted. The observations give a radar cross-section of 0.50 +/- 0.13 km(2), and an upper limit to the width of the (unresolved) echo spectrum of less than 1 Hz. These results are consistent with specular reflection from a solid nucleus having a radius of less than 0.4 km. The upper limit depends on the unknown rotation rate and scattering law. Two other comets, comets Austin and P/Churyumov-Gerasimenko have also been probed but have not returned any detectable echo, thus allowing one to put only an upper limit on the sizes of their nuclei. (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 Aerosp, Cannes, France. Univ Nice, Nice, France. Cornell Univ, Ithaca, NY USA. MIT, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kamoun, P (reprint author), Aerosp, Cannes, France. NR 11 TC 9 Z9 9 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD JAN-FEB PY 1999 VL 47 IS 1-2 BP 23 EP 28 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 179JT UT WOS:000079324100004 ER PT J AU Cavelier, J Wright, SJ Santamaria, J AF Cavelier, J Wright, SJ Santamaria, J TI Effects of irrigation on litterfall, fine root biomass and production in a semideciduous lowland forest in Panama SO PLANT AND SOIL LA English DT Article DE below ground-productivity; biomass; fine roots; irrigation; litterfall; lowland forest ID RAIN-FOREST; NUTRIENT AVAILABILITY; SEASONAL DROUGHT; TROPICAL FOREST; MOIST FOREST; COSTA-RICA; UNDERSTORY; GROWTH; PHENOLOGY; DYNAMICS AB The effects of irrigation on fine root biomass, root production and litterfall were measured at the community level, in a semideciduous lowland forest in Panama. Biomass of roots less than 2 mm in dia. in the first 10 cm of the soil (measured with soil cores), was higher in irrigated (1.80 Mg ha(-1)) than in non-irrigated plots (1.24 Mg ha(-1)). During the dry season, productivity of roots (measured with ingrowth cylinders filled with root-free soil), was higher in irrigated (1.6 g m(-2) day(-1)) than in control plots (0.3 g m(-2) day(-1)). In control plots, root productivity was highly seasonal. Maximum root growth into the root-free soil, occurred during the transitions from dry to wet, and from wet to dry season, possibly as a response to water and/or nutrient pulses. Litterfall was not significantly different between irrigated (3.8 g m(-2) day(-1)) and control plots (3.7 g m(-2) day(-1)). The results of this study show that root-productivity is limited by the water supply during the dry season, and that water by itself, is not a limiting factor for community-level litter production. C1 Univ Los Andes, Dept Ciencias Biol, Santafe Bogota, Colombia. Smithsonian Trop Res Inst, Balboa, Panama. RP Cavelier, J (reprint author), Univ Los Andes, Dept Ciencias Biol, Santafe Bogota, Colombia. RI Wright, Stuart/M-3311-2013 OI Wright, Stuart/0000-0003-4260-5676 NR 46 TC 36 Z9 37 U1 0 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0032-079X J9 PLANT SOIL JI Plant Soil PY 1999 VL 211 IS 2 BP 207 EP 213 DI 10.1023/A:1004686204235 PG 7 WC Agronomy; Plant Sciences; Soil Science SC Agriculture; Plant Sciences GA 261PX UT WOS:000084018600008 ER PT J AU Matamala, R Drake, BG AF Matamala, R Drake, BG TI The influence of atmospheric CO2 enrichment on plant-soil nitrogen interactions in a wetland plant community on the Chesapeake Bay SO PLANT AND SOIL LA English DT Article DE denitrification; elevated CO2; exchangeable N (NH4+); potential net N mineralization; Scirpus olneyi ID CARBON-DIOXIDE ENRICHMENT; ELEVATED CO2; ESTUARINE MARSH; SCIRPUS-OLNEYI; LOLIUM-PERENNE; LEAF-LITTER; GAS FLUXES; DECOMPOSITION; PHOTOSYNTHESIS; DENITRIFICATION AB We investigated plant and soil nitrogen pools and soil processes in monospecific stands of the C-3 sedge Scirpus olneyi and the C-4 grass Spartina patens grown in the field in open top chambers in a brackish marsh on the Chesapeake Bay. Stands of S. olneyi responded to eight years of elevated CO2, by increased rates of net ecosystem gas exchange and a large stimulation of net ecosystem production. We conducted our study in the summer of 1994 and 1995 when soil cores were collected and aboveground biomass was estimated. Nitrogen concentration in elevated CO2 treatments was reduced 15% in stems of S. olneyi and 8% in the upper 10 cm of the soil profile. While total plant nitrogen per unit of land area remained the same between treatments, total soil nitrogen showed a non-significant tendency to decrease in the upper 10 cm of the soil profile in elevated CO2 both years of study. A significant decrease in soil bulk density largely contributed to the observed decrease in soil nitrogen. Exchangeable nitrogen and potential denitrification rates were also reduced in elevated CO2, but net nitrogen mineralization was unchanged by elevated CO2 treatment in S. olneyi both years. Plants and soils in a pure stand of the C-4 grass, S. patens, showed none of these effects of elevated CO2 treatment. Our data provides evidence of changes in nitrogen dynamics of an ecosystem exposed to elevated CO2 for eight years; however due to the variability in these data, we cannot say if or how these changes are likely to impact the effect of rising CO2 on primary production or carbon accumulation in this ecosystem in the future. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Matamala, R (reprint author), Duke Univ, Dept Bot, POB 90340, Durham, NC 27708 USA. NR 41 TC 16 Z9 21 U1 1 U2 8 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0032-079X J9 PLANT SOIL JI Plant Soil PY 1999 VL 210 IS 1 BP 93 EP 101 DI 10.1023/A:1004690220705 PG 9 WC Agronomy; Plant Sciences; Soil Science SC Agriculture; Plant Sciences GA 235FU UT WOS:000082531300010 ER PT J AU Lovelock, CE Virgo, A Popp, M Winter, K AF Lovelock, CE Virgo, A Popp, M Winter, K TI Effects of elevated CO2 concentrations on photosynthesis, growth and reproduction of branches of the tropical canopy tree species, Luehea seemannii Tr. & Planch. SO PLANT CELL AND ENVIRONMENT LA English DT Article DE Luehea seemannii Tr. & Planch.; branch autonomy; branch-bag; carbohydrate; elevated CO2; forest canopy; growth; photosynthesis ID PINUS-TAEDA TREES; ATMOSPHERIC CO2; CARBON-DIOXIDE; GAS-EXCHANGE; WATER-USE; ENRICHMENT; FOREST; RESPONSES; LEAF; SOIL AB Mature trees have already experienced substantial increases in CO2 concentrations during their lifetimes, and will experience continuing increases in the future. Small open-top chambers were used to enclose branchlets that were at a height of between 20 and 25 m in the canopy of the tree species Luehea seemannii Tr. & Planch. in a tropical forest in Panama. Elevated concentrations of CO2 increased the rate of photosynthetic carbon fixation and decreased stomatal conductance of leaves, but did not influence the growth of leaf area per chamber, the production of flower buds and fruit nor the concentration of nonstructural carbohydrates within leaves. The production of flower buds was highly correlated with the leaf area produced in the second flush of leaves, indicating that the branchlets of mature trees of Luehea seemannii are autonomous to a considerable extent. Elevated levels of CO2 did increase the concentration of nonstructural carbohydrates in woody stem tissue. Elevated CO2 concentration also they increased the ratio of leaf area to total biomass of branchlets, and tended to reduce individual fruit weight. These data suggest that the biomass allocation patterns of mature trees may change under future elevated levels of CO2. Although there were no effects on growth during the experiment, the possibility of increased growth in the season following CO2 enrichment due to increased carbohydrate concentrations in woody tissue cannot be excluded. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Smithsonian Trop Res Inst, Balboa, Panama. Univ Vienna, Inst Plant Physiol, A-1091 Vienna, Austria. RP Lovelock, CE (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. EM lovelock@serc.si.edu RI Popp, Marianne/E-7559-2012; Lovelock, Catherine/G-7370-2012 OI Lovelock, Catherine/0000-0002-2219-6855 NR 53 TC 23 Z9 26 U1 0 U2 7 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0140-7791 J9 PLANT CELL ENVIRON JI Plant Cell Environ. PD JAN PY 1999 VL 22 IS 1 BP 49 EP 59 DI 10.1046/j.1365-3040.1999.00370.x PG 11 WC Plant Sciences SC Plant Sciences GA 204AT UT WOS:000080741300005 ER PT J AU Pedersen, LB Kress, WJ AF Pedersen, LB Kress, WJ TI Honeyeater (Meliphagidae) pollination and the floral biology of Polynesian Heliconia (Heliconiaceae) SO PLANT SYSTEMATICS AND EVOLUTION LA English DT Article DE Heliconia; Foulehaio; honeyeaters; pollination; plant reproductive biology; nectar; breeding systems; Samoa; Fiji ID RAIN-FOREST; NECTAR; BIRDS AB The primary pollinator of Polynesian heliconias, Heliconia laufao and H. paka, is the Wattled Honeyeater, Foulehaio carunculata. This report is the first documentation of pollination by honeyeaters in the genus Heliconia and the first record of F: carunculata as a pollinator of a plant species. The Polynesian heliconias bear inflorescences that produce 2-4 hermaphroditic flowers per day for a period of 2-3 months. Each flower secretes abundant nectar (125-184 mu l) with low sugar concentration (15-18% sucrose-equivalents, weight per weight basis) which is available at anthesis just before dawn. Ninety percent of flower visits occur between anthesis and mid-morning. The honeyeaters perch on inflorescence bracts, and probing of the flower results in pollen deposition on the head and bill from where pollen is transferred between flowers. No statements on compatibility can be made for Heliconia paka; however, Heliconia laufao appears to be self-compatible. Calculations of energetic values of nectar of the Polynesian heliconias and Daily Energy Expenditures of F: carunculata suggest that populations of H. laufao and H. paka serve as rich energy resources for their pollinators. C1 Univ Copenhagen, Inst Bot, Bot Lab, DK-1123 Copenhagen K, Denmark. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Pedersen, LB (reprint author), Univ Copenhagen, Inst Bot, Bot Lab, Gothersgade 140, DK-1123 Copenhagen K, Denmark. NR 36 TC 4 Z9 6 U1 1 U2 11 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0378-2697 J9 PLANT SYST EVOL JI Plant Syst. Evol. PY 1999 VL 216 IS 1-2 BP 1 EP 21 DI 10.1007/BF00985098 PG 21 WC Plant Sciences; Evolutionary Biology SC Plant Sciences; Evolutionary Biology GA 193YX UT WOS:000080166300001 ER PT B AU Nisenson, P Contos, A Korzennik, S Noyes, R Brown, T AF Nisenson, P Contos, A Korzennik, S Noyes, R Brown, T BE Hearnshaw, JB Scarfe, CD TI The Advanced Fiber-Optic Echelle (AFOE) and extrasolar planet searches SO PRECISE STELLAR RADIAL VELOCITIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT IAU Colloquium 170 on Precise Stellar Radial Velocities CY JUN 21-26, 1998 CL VICTORIA, CANADA SP IAU Commiss 30 AB The Advanced Fiber-Optic Echelle (AFOE) is a fiber-fed bench-top spectrograph specifically designed for precise radial velocity observations. The AFOE is permanently located at the 1.5-m telescope at Smithsonian's Whipple Observatory in Arizona and is regularly used for monitoring exo-planet candidate stars and for asteroseismology observations. In this paper, we discuss the status of the instrument, as well as an upgrade to the instrument, a Fabry-Perot reference, which may prove important both for the AFOE and for all precise radial velocity (PRV) facilities. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Nisenson, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 4 TC 3 Z9 3 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-011-0 J9 ASTR SOC P PY 1999 VL 185 BP 143 EP 153 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP16N UT WOS:000084260500022 ER PT B AU Noyes, RW Contos, AR Korzennik, SG Nisenson, P Brown, TM Horner, SD AF Noyes, RW Contos, AR Korzennik, SG Nisenson, P Brown, TM Horner, SD BE Hearnshaw, JB Scarfe, CD TI The planet orbiting rho Coronae Borealis SO PRECISE STELLAR RADIAL VELOCITIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT IAU Colloquium 170 on Precise Stellar Radial Velocities CY JUN 21-26, 1998 CL VICTORIA, CANADA SP IAU Commiss 30 ID MIGRATION AB Continuing precise radial velocity observations of rho Coronae Borealis have allowed the determination of updated parameters of the 40-day orbit of its Jupiter-mass companion. This confirms the previously reported period and amplitude, and shows a small but marginally significant non-zero eccentricity. It also provides improved predictions for the times of possible transit of the companion in front of the star. The new data provide upper limits to the mass of a possible second companion to the system. The orbital parameters are discussed in the light of scenarios for the origin and migration of extra-solar giant planets. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Noyes, RW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 12 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 1-58381-011-0 J9 ASTR SOC P PY 1999 VL 185 BP 162 EP 165 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP16N UT WOS:000084260500024 ER PT B AU Stefanik, RP Latham, DW Torres, G AF Stefanik, RP Latham, DW Torres, G BE Hearnshaw, JB Scarfe, CD TI Radial-Velocity Standard Stars SO PRECISE STELLAR RADIAL VELOCITIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT IAU Colloquium 170 on Precise Stellar Radial Velocities CY JUN 21-26, 1998 CL VICTORIA, CANADA SP IAU Commiss 30 ID SOLAR-TYPE STARS; COMPANIONS; BINARIES AB We review the history of the IAU Radial Velocity Standard Stars and give a status report on recent efforts at the Harvard-Smithsonian Center for Astrophysics to establish an absolute velocity zero point for these stars and to improve their usefulness for intercomparing the results from different instruments and observatories. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Stefanik, RP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 30 TC 33 Z9 36 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-011-0 J9 ASTR SOC P PY 1999 VL 185 BP 354 EP 366 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP16N UT WOS:000084260500052 ER PT B AU Latham, DW AF Latham, DW BE Hearnshaw, JB Scarfe, CD TI Future directions for radial-velocity research SO PRECISE STELLAR RADIAL VELOCITIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT IAU Colloquium 170 on Precise Stellar Radial Velocities CY JUN 21-26, 1998 CL VICTORIA, CANADA SP IAU Commiss 30 ID GIANT PLANETS; STARS; ECCENTRICITY; SAMPLE AB I review the status of ground-based radial-velocity searches for extra-solar planets and speculate about the new results that can be expected in this field over the coming years. Then I review the plans for astrometric space missions and speculate about the impact that these missions will have on ground-based radial-velocity work, citing the specific examples of extra-solar planet research, the mass-luminosity relation for M dwarfs and metal-poor stars, and Galactic structure and evolution. 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 17 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 1-58381-011-0 J9 ASTR SOC P PY 1999 VL 185 BP 401 EP 409 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP16N UT WOS:000084260500057 ER PT J AU Krombein, KV Lelej, AS AF Krombein, KV Lelej, AS TI Biosystematic studies of Ceylonese wasps, XXII: Bethsmyrmilla, a new genus of mutillid wasps (hymenoptera : Mutileidae : Myrmillinae) SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Mutillid wasps; Bethsmyrmilla alticola; new genus and new species; Sri Lanka; Lasioglossum (Sudila) alphenum (Cameron) AB Bethsmyrmilla alticola, new genus and new species is described from Sri Lanka. A key is given to the Oriental genera of Myrmillinae. The halictine bee Lasioglossum (Sudila) alphenum (Cameron) is the probable host of B. alticola. C1 Natl Museum Nat Hist, Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Krombein, KV (reprint author), Natl Museum Nat Hist, Smithsonian Inst, Dept Entomol, MRC 165, Washington, DC 20560 USA. NR 4 TC 1 Z9 3 U1 0 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 JAN PY 1999 VL 101 IS 1 BP 143 EP 148 PG 6 WC Entomology SC Entomology GA 163FF UT WOS:000078392700014 ER PT J AU Adamski, D AF Adamski, D TI Blastobasis graminea, new species (Lepidoptera : Gelechioidea : Coleophoridae : Blastobasinae), a stem borer of sugar cane in Colombia and Venezuela SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Coleophoridae; Blastobasinae; Blastobasis; sugar cane; Colombia; Venezuela AB Blastobasis graminea, new species, a stem borer of sugar cane in Colombia and Venezuela, is described and illustrated. For the first time, a larva of Blastibasini is described in detail. Scanning electron micrographs of the larva, illustrations of the larval mandible, setal maps, and photographs of larval damage and pupation sites are provided. Auximobasis obstricta Meyrick 1918, is transferred to Blastobasis Zeller 1855, n. comb., and Blastobasis subolivacea Walsingham 1897, is transferred to Holcocera Clemens 1863, n. comb. C1 Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Adamski, D (reprint author), Smithsonian Inst, Dept Entomol, MRC-127, Washington, DC 20560 USA. NR 15 TC 6 Z9 6 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 JAN PY 1999 VL 101 IS 1 BP 164 EP 174 PG 11 WC Entomology SC Entomology GA 163FF UT WOS:000078392700016 ER PT B AU Wilkes, BJ AF Wilkes, BJ BE Ferland, G Baldwin, J TI The spectral energy distributions of active galactic nuclei. SO QUASARS AND COSMOLOGY SE Astronomical Society of the Pacific Conference Series LA English DT Review CT Meeting on Quasars and Cosmology CY MAY 18-22, 1998 CL LA SERENA, CHILE SP Astron Soc Pacific ID RADIO-QUIET QUASARS; X-RAY-SPECTRA; FE-II EMISSION; BIG BLUE BUMP; TYPE-2 SEYFERT-GALAXIES; ACCRETION DISK MODELS; ASCA OBSERVATIONS; HOST GALAXIES; COLD MATTER; OPTICAL-PROPERTIES AB Key to our understanding of the workings of the most powerful energy sources in the universe, active galactic nuclei (AGN), are full, multi-wavelength observations of their emission. In this article the current observational status of AGN spectral energy distributions (SEDs) throughout the radio-gamma-ray spectral regions is reviewed along with our intepretation of them and discussion of key areas which remain insufficiently explored. The past decade has seen great strides in a number of spectral regions including: X-ray, gamma-ray, infrared (IR), mm; and has resulted in observed SEDs for a larger and more representative fraction of the AGN population. This has led to a, sometimes reluctant, concensus on the important energy generation mechanisms in the various wavelength bands. However there are key spectral regions which remain beyond our observational capabilities, the EUV in particular, and regions where the full potential of current instrumentation has not yet been achieved, far-infrared and mm. The inter-relation between the emission in the various spectral bands is discussed along with currently popular scenarios to explain both these relations and the SEDs in general. This is followed by a discussion of the role of dust and related emission line studies as well as the newly recognised class of NLSy1 galaxies. The article concludes with the suggestion, based on the results in a number of widely different studies discussed here, that orientation may play an important role in determing the observed properties of AGN with the pole-on view being provided by NLSy1 galaxies. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 145 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 1-886733-83-X J9 ASTR SOC P PY 1999 VL 162 BP 15 EP 42 PG 28 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN27U UT WOS:000081412200002 ER PT B AU Green, PJ AF Green, PJ BE Ferland, G Baldwin, J TI Review: Emission lines and the high energy continuum SO QUASARS AND COSMOLOGY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Meeting on Quasars and Cosmology CY MAY 18-22, 1998 CL LA SERENA, CHILE SP Astron Soc Pacific ID ACTIVE GALACTIC NUCLEI; QUASI-STELLAR OBJECTS; BROAD-ABSORPTION-LINE; FE-II EMISSION; X-RAY ABSORPTION; SEYFERT-GALAXIES; ACCRETION DISK; OPTICAL POLARIZATION; SPECTRA; LUMINOSITY AB Quasars show many striking relationships between emission line and continuum radiation. The physical origin of these diverse and interrelated correlations has yet to be determined. We take as an example the observed anticorrelation between emission line equivalent width and underlying continuum luminosity (the Baldwin Effect). We examine mechanisms that might account for 4 particularly intriguing characteristics of the Baldwin Effect. In nearly every case, more than one such mechanism must be invoked. We argue that the most promising mechanism is that the spectral energy distribution (SED) of the overall quasar continuum changes with luminosity, driving emission lines differently depending on their effective ionization energies. Several lines of evidence point to the sobering fact that the SEDs we observe are not those impinging on the emission line clouds, but instead may be strongly affected by (both neutral and ionized) absorption and by scattering. Interpretation of the data is complicated because, even in assumed flattened geometries, the standard accretion disk, broad emission line region, molecular torus, and narrow emission line region are not necessarily aligned. A multiwavelength approach with particular attention to the interplay of absorption and emission shows promise for significant advances in our understanding. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Green, PJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 84 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 1-886733-83-X J9 ASTR SOC P PY 1999 VL 162 BP 265 EP 292 PG 28 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN27U UT WOS:000081412200018 ER PT J AU Haberle, SG Maslin, MA AF Haberle, SG Maslin, MA TI Late Quaternary vegetation and climate change in the Amazon basin based on a 50,000 year pollen record from the Amazon fan, ODP site 932 SO QUATERNARY RESEARCH LA English DT Article DE palynology; oxygen isotopes; tropical forest; last glacial maximum; Amazon River; Amazon Fan ID ANDEAN TECTONICS; BRAZIL; SEDIMENTS; PALEOENVIRONMENTS; FLUCTUATIONS; HISTORY; PANAMA; FOREST; MODEL; CYCLE AB Hemipelagic sediments from the Amazon deep-sea fan, ODP Site 932 (5 degrees 12.7'N, 47 degrees 1.8'W), and continental shelf provide a 50,000-yr-long pollen record of Amazon Basin vegetation. The age model for Hole 932A is constrained by eight magnetic remanence intensity features, one paleomagnetic excursion, and three AMS (14)C dates. Alchornea, Melastomataceae, Myrtaceae, and Moraceae/Urticaceae are dominant taxa in the pollen record between 40,200 and 19,800 cal yr B.P. Andean taxa, such as Podocarpus and Hedyosmum, increase in abundance between 19,800 and 11,000 cal yr B.P, and prior to 40,200 cal yr B.P. The Holocene pollen assemblage, derived from Amazon River and continental shelf sediments, is dominated by secondary growth taxa, such as Cecropia. Climatic factors influencing the development of glacial and interglacial tropical vegetation are considered by comparing marine with terrestrial records of vegetation change. This comparison shows that the Amazon Basin forests were not extensively replaced by savanna vegetation during the glacial period, contradicting the refugia hypothesis. (C) 1999 University of Washington. C1 Smithsonian Trop Res Inst, Balboa, Panama. UCL, Dept Geog, Environm Change Res Ctr, London WC1H 0AP, England. Monash Univ, Dept Geog & Environm Sci, Clayton, Vic 3168, Australia. RP Haberle, SG (reprint author), Monash Univ, Dept Geog & Environm Sci, Clayton, Vic 3168, Australia. EM simon.haberle@arts.monash.edu.au OI Haberle, Simon/0000-0001-5802-6535 NR 57 TC 132 Z9 137 U1 3 U2 24 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0033-5894 J9 QUATERNARY RES JI Quat. Res. PD JAN PY 1999 VL 51 IS 1 BP 27 EP 38 DI 10.1006/qres.1998.2020 PG 12 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 158WJ UT WOS:000078140200003 ER PT S AU Harris, DE Biretta, JA Junor, W AF Harris, DE Biretta, JA Junor, W BE Roser, HJ Meisenheimer, K TI The large scale X-ray emission from M 87 SO RADIO GALAXY MESSIER 87 SE LECTURE NOTES IN PHYSICS LA English DT Proceedings Paper CT Workshop on Radio Galaxy Messier 87 CY SEP 15-19, 1997 CL SCHLOSS RINGBERG CASTLE, GERMANY ID RADIO HALO; M87 AB We describe asymmetrical features in a long exposure X-ray map of M 87 made with the ROSAT High Resolution Imager (HRI). A bright triangular region is marked by a linear 'spur' along one edge. The structure of this spur suggests an interpretation of a tangential view of a shock front 18 kpc long. None of the brighter features are spatially coincident with radio or optical structures so we concur with earlier investigators that most of the emission arises from thermal processes. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Harris, DE (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0075-8450 BN 3-540-66209-X J9 LECT NOTES PHYS PY 1999 VL 530 BP 100 EP 105 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ23N UT WOS:000087682000012 ER PT S AU Harris, DE Biretta, JA Junor, W AF Harris, DE Biretta, JA Junor, W BE Roser, HJ Meisenheimer, K TI X-ray variability in M 87: 1992-1998 SO RADIO GALAXY MESSIER 87 SE LECTURE NOTES IN PHYSICS LA English DT Proceedings Paper CT Workshop on Radio Galaxy Messier 87 CY SEP 15-19, 1997 CL SCHLOSS RINGBERG CASTLE, GERMANY AB Beginning in 1995 June, we have obtained an observation of M 87 with the ROSAT High Resolution Imager (HRI) every 6 months. We present the measurements of X-ray intensity for the core and knot A through 1998 January. We find significant changes in both components. For the core, intensities measured in June 1995, December 1996, and December 1997 are roughly 30% higher than values obtained at three intervening times. For knot A, a secular decrease of approximately 15% is interrupted only by an intensity jump (3 sigma) in December 1997. Because the background used for subtraction is probably underestimated, we suspect the actual variation is somewhat greater than these values indicate. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Harris, DE (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0075-8450 BN 3-540-66209-X J9 LECT NOTES PHYS PY 1999 VL 530 BP 319 EP 323 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ23N UT WOS:000087682000032 ER PT J AU Lefsky, MA Harding, D Cohen, WB Parker, G Shugart, HH AF Lefsky, MA Harding, D Cohen, WB Parker, G Shugart, HH TI Surface lidar remote sensing of basal area and biomass in deciduous forests of eastern Maryland, USA SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID NORTHERN HARDWOOD FORESTS; LASER SCANNER DATA; AIRBORNE LIDAR; CANOPY; HEIGHT; STANDS; VOLUME; SYSTEM; STRATIFICATION; SUCCESSION AB A method of predicting two forest stand structure attributes, basal area and aboveground biomass, from measurements of forest vertical structure was developed and tested using field and remotely sensed canopy structure measurements. Coincident estimates of the vertical distribution of canopy structure measurements. Coincident estimates of the vertical distribution of canopy surface area (the canopy height profile), and field-measured stand structure attributes were acquired for two data sets. the chronosequence data set consists of 48 plots in stands distributed within 25 miles of Annapolis, MD, with canopy height profiles measured in the field using the optical-quadrat method. The stem-map data set consists of 75 plots subsetted from a single 32 ha stem-mapped stand, with measurements of their canopy height profiles made using the SLICER (Scanning Lidar Imager of Canopies by Echo Recovery) instrument, an airborne surface lidar system. Four height indices, maximum, median, mean, and quadratic mean canopy height (QMCH) were calculated from the canopy height profiles. Regressions between the indices and stand basal area and biomass were developed using the chronosequence data set. The regression equations developed from the chronosequence data set were then applied to height indices calculated from the remotely sensed canopy height profiles from the stem map data set, and the ability of the regression equations to predict the stem map plot's stand structure attributes was then evaluated. The QMCH was found to explain the most variance in the chronosequence data set's stand structure attributes, and to most accurately predict the values of the same attributes in the stem map data set. For the chronosequence data set, the QMCH predicted 70% of variance in stand basal area, and 80% of variance in aboveground biomass, and remained nonasymptotic with basal areas up to 50 m(2) ha(-1), and aboveground biomass values up to 450 Mg ha(-1). When applies to the stem-map data set, the regression equations resulted in basal areas that were, on average, underestimated by 2.1 m(2) ha(-1), and biomass values were underestimated by 16 Mg ha(-1), and explained 37% and 33% of variance, respectively. Differences in the magnitude of the coefficients of determination were due to the wider range of stand conditions found in the chronosequence data set; the standard deviation of residual values were lower in the stem map data set than on the chronosequence data sets. Stepwise multiple regression was performed to predict the two stand structure attributes using the canopy height profile data directly as independent variables, but they did not improve the accuracy of the estimates over the height index approach. Published by Elsevier Science Inc. C1 US Forest Serv, USDA, Pacific NW Res Stn, Forestry Sci Lab, Corvallis, OR 97331 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. NASA, Goddard Space Flight Ctr, Terr Phys Lab, Greenbelt, MD 20771 USA. Univ Virginia, Dept Environm Sci, Charlottesville, VA 22903 USA. RP Lefsky, MA (reprint author), US Forest Serv, USDA, Pacific NW Res Stn, Forestry Sci Lab, 3200 SW Jefferson Way, Corvallis, OR 97331 USA. RI Lefsky, Michael/A-7224-2009; Shugart, Herman/C-5156-2009; Harding, David/F-5913-2012; OI Parker, Geoffrey/0000-0001-7055-6491 NR 44 TC 346 Z9 374 U1 14 U2 106 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD JAN PY 1999 VL 67 IS 1 BP 83 EP 98 DI 10.1016/S0034-4257(98)00071-6 PG 16 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 151KV UT WOS:000077720000006 ER PT J AU Nagamitsu, T Momose, K Inoue, T Roubik, DW AF Nagamitsu, T Momose, K Inoue, T Roubik, DW TI Preference in flower visits end partitioning in pollen diets of stingless bees in an Asian tropical rain forest SO RESEARCHES ON POPULATION ECOLOGY LA English DT Article DE flower visitation; foraging; pollen preference; resource partitioning; Sarawak; Trigona ID FORAGING BEHAVIOR; RESOURCE; MECHANISM; FIELD AB Floral resource partitioning among stingless bees (Trigona, Meliponini, Apidae) in a lowland rain forest in Sarawak, Malaysia, was investigated using tree towers and walkways in a it-year study that included a general flowering period. We obtained 100 collections of insect visitors to flowers of varying floral location and shape representing 81 plant species. The tendency of 11 species of stingless bees to visit specific flowers with a particular floral location and shape was analyzed by logistic regression analysis. This analysis showed that the proportion of flower visitor collections containing Trigona fuscobalteata and T. melanocephala differed according to floral location. The former was frequently collected at canopy and gap flowers, whereas the latter was most often collected at understory flowers. The analysis also suggested that T. erythrogastra was more rarely collected at shallow flowers than at deep flowers. Analysis of the pollen diets of T. collina, T. fuscobalteara, T. melanocephala, and T. melina revealed that similarity of pollen sources differed among the six permutated pairs of the four species. The lowest mean rank of similarity found was between T. fuscobalteata and T. melanocephala. This result supports the hypothesis that preference in visiting flowers in different locations leads to pollen resource partitioning. C1 Forestry & Forest Prod Res Inst, Hokkaido Res Ctr, Sapporo, Hokkaido 0628516, Japan. Kyoto Univ, Grad Sch Asian & African Area Studies, Kyoto 606, Japan. Kyoto Univ, Ctr Ecol Res, Otsu, Shiga, Japan. Smithsonian Trop Res Inst, Balboa, Panama. RP Nagamitsu, T (reprint author), Forestry & Forest Prod Res Inst, Hokkaido Res Ctr, 7 Hitsujigaoka, Sapporo, Hokkaido 0628516, Japan. RI Nagamitsu, Teruyoshi/J-7710-2015 OI Nagamitsu, Teruyoshi/0000-0003-3366-7197 NR 36 TC 22 Z9 22 U1 0 U2 6 PU SPRINGER-VERLAG TOKYO PI TOKYO PA 3-3-13, HONGO, BUNKYO-KU, TOKYO, 113, JAPAN SN 0034-5466 J9 RES POPUL ECOL JI Res. Popul. Ecol. PY 1999 VL 41 IS 2 BP 195 EP 202 PG 8 WC Ecology SC Environmental Sciences & Ecology GA 245BD UT WOS:000083085600010 ER PT J AU Hogan, CJ Kirshner, RP Suntzeff, NB AF Hogan, CJ Kirshner, RP Suntzeff, NB TI Surveying space-time with supernovae SO SCIENTIFIC AMERICAN LA English DT Article C1 Univ Washington, Dept Astron, Seattle, WA 98195 USA. Harvard Univ, Cambridge, MA 02138 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Santa Cruz, La Serena, Chile. RP Hogan, CJ (reprint author), Univ Washington, Dept Astron, Seattle, WA 98195 USA. NR 3 TC 5 Z9 5 U1 0 U2 0 PU SCI AMERICAN INC PI NEW YORK PA 415 MADISON AVE, NEW YORK, NY 10017 USA SN 0036-8733 J9 SCI AM JI Sci.Am. PD JAN PY 1999 VL 280 IS 1 BP 46 EP 51 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 148LQ UT WOS:000077507100025 ER PT S AU Cranmer, SR Field, GB Kohl, JL AF Cranmer, SR Field, GB Kohl, JL BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI The impact of ion-cyclotron wave dissipation on heating and accelerating the fast solar wind SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID ULTRAVIOLET CORONAGRAPH SPECTROMETER; ALFVEN WAVES; RESONANT ACCELERATION; TRANSPORT-EQUATIONS; PLASMA; TEMPERATURES; ANISOTROPY; DENSITIES; MOMENTUM; MODEL AB Using empirical ion velocity distributions derived from UVCS and SUMER ultraviolet spectroscopy, we construct theoretical models of the nonequilibrium plasma state of the polar solar corona. The primary energy deposition mechanism we investigate is the dissipation of high frequency (10-10000 Hz) ion-cyclotron resonant Alfven waves which can heat and accelerate ions differently depending on their charge and mass. We find that it is possible to explain many of the kinetic properties of the plasma with relatively small amplitudes for the resonant waves. There is evidence for steepening of the Alfven wave spectrum between the coronal base and the largest heights observed spectroscopically, and it is important to take Coulomb collisions into account to understand observations at the lowest heights. Because the ion-cyclotron wave dissipation is rapid, the extended heating seems to demand a constantly replenished population of waves over several solar radii. This indicates that the waves are probably generated throughout the wind rather than propagated up from the base of the corona. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cranmer, SR (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 41 TC 8 Z9 8 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 35 EP 38 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700005 ER PT S AU Frazin, RA Modigliani, A Ciaravella, A Dennis, E Fineschi, S Gardner, LD Michels, J O'Neal, R Raymond, JC Wu, CR Noci, G Kohl, JL AF Frazin, RA Modigliani, A Ciaravella, A Dennis, E Fineschi, S Gardner, LD Michels, J O'Neal, R Raymond, JC Wu, CR Noci, G Kohl, JL BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI UVCS SOHO observations of coronal streamers SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID SOLAR-WIND; SPECTROMETER; IONS AB We used the Ultraviolet Coronagraph Spectrometer (UVCS) on the Solar and Heliospheric Observatory (SOHO) to obtain line profiles in mid-latitude coronal streamers between 1.3 R. and 5.5 R. during a period of moderate solar activity. We present a summary of the preliminary results. These results clearly indicate that the mid-latitude streamers observed during this time period have very different spectral properties than the equatorial streamers observed near solar minimum. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Frazin, RA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Frazin, Richard/J-2625-2012 NR 9 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 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 235 EP 238 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700040 ER PT S AU Miralles, MP Strachan, L Gardner, LD Smith, PL Kohl, JL Guhathakurta, M Fisher, RR AF Miralles, MP Strachan, L Gardner, LD Smith, PL Kohl, JL Guhathakurta, M Fisher, RR BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Physical properties of coronal streamers as observed by Spartan 201 SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID SOLAR-WIND ACCELERATION; NEUTRAL HYDROGEN; 2-FLUID MODEL; WHITE-LIGHT; ORIGINS AB The three Spartan 201 flights from 1993 to 1995 provided us with observations in HI Lyman-alpha of several streamers in the declining phase of the current solar cycle. Analysis of the heliocentric height dependence of the HI Ly-alpha LOS velocity distribution width clearly show that there is a maximum in the proton 1/e velocities at heights ranging from 2.1 to 2.5 R. for all of the observed streamers. We compare UVCS/Spartan results with proton velocity distributions from UVCS/SOHO during solar minimum. We also discuss differences in the proton velocity distributions for different types of streamers over the three year period of Spartan 201 observations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Miralles, MP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 20 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 239 EP 242 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700041 ER PT S AU Vasquez, AM van Ballegooijen, AA Raymond, JC AF Vasquez, AM van Ballegooijen, AA Raymond, JC BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Model of solar wind flow near an equatorial coronal streamer SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys AB In a previous work (1) we developed a semiempirical axisymmetric and magnetostatic model of the minimum activity corona, accounting for the gas pressure gradient effects on the magnetic structure. The model is able to reproduce the streamer belt closed region and the streamer sourrounding open field lines, predicting high plasma beta values (> 1) in the closed region, low values in the sourrounding open-held regions (streamer legs) and even lower values for the polar hole region. In this work we add to that model a solar wind solution under the assumption of mass and momentum flux conservation. For open field lines arising from the polar hole region we find a fast wind solution that reaches values of about 600 km/sec at 10 R.. For open field lines arising from the surroundings of the closed region (streamer legs), the morphology of the field lines is fast diverging, we find that this results in the existence of two possible sonic points. The first sonic point, located below the streamer cusp, gives a relatively fast solar wind solution, reaching values of about 400 km/sec at 10 R.. The second sonic point, located above the streamer cusp, gives a slow solution, reaching values of up to 200 km/sec for lines close to the streamer core, becoming supersonic only well above the streamer cusp. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Vasquez, AM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 15, Cambridge, MA 02138 USA. NR 4 TC 8 Z9 8 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 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 243 EP 246 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700042 ER PT S AU Wood, CH Habbal, SR Esser, R Penn, M AF Wood, CH Habbal, SR Esser, R Penn, M BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Comparison of Fe lambda 5303, lambda 6374 and lambda 7892 spectral line observations in a coronal hole and streamer SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID INNER CORONA AB We present intensity and line width measurements of the Fe X lambda 6374, Fe XI lambda 7892 and Fe XIV lambda 5303 lines between 1.03 and 1.4 R-s in a coronal hole and a streamer. The observations were made at the National Solar Observatory at Sacramento Peak on 26 February 1998. In the coronal hole, only the Fe X line was observed; an upper limit of 10(6) K for the electron temperature and 28 km/s for the amplitude of nonthermal motions was inferred from the Fe X measurements at 1.06 R-s. While all three lines were observed in the streamer, the unique result was that the width of the Fe XI line increased with heliocentric distance as opposed to a decrease in the Fe X and Fe XIV line widths. We interpret this as evidence for the existence of multitemperature static plasmas, and a solar wind outflow at the streamer base. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Wood, CH (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 7 TC 1 Z9 1 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 293 EP 296 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700055 ER PT S AU Dobrzycka, D Panasyuk, AV Strachan, L Kohl, JL AF Dobrzycka, D Panasyuk, AV Strachan, L Kohl, JL BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Geometry, physical properties and outflow velocities from the polar and equatorial coronal holes UVCS SOHO observations SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID SOLAR-WIND AB We analyzed the UVCS/SOHO data obtained during the Whole Sun Month campaign in 1996 and compared the H I Ly alpha (1216 Angstrom) and O VI (1032 Angstrom, 1037 Angstrom) emission in the polar and equatorial coronal holes. We found that the emission lines have similar characteristics in these two types of coronal holes. Both types show evidence for superradially diverging boundaries. We used the O VI (1032 Angstrom) and O VI (1037 Angstrom) local emissivities, determined from the 3D tomographic reconstruction of the solar corona, to investigate the outflow velocities from the polar and equatorial coronal holes. The latitudinal distribution of the O VI ratio at 2.21 R., free from the line-of-sight effect, shows evidence that the equatorial coronal hole may have O+5 outflow velocities lower than in the polar coronal holes. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Dobrzycka, D (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 17 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 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 305 EP 308 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700058 ER PT S AU Karovska, M Wood, BE Brueckner, GE Cook, JW Howard, RA AF Karovska, M Wood, BE Brueckner, GE Cook, JW Howard, RA BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI LASCO observations of the solar polar regions SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys AB We describe our study of the dynamical properties of coronal structures in the polar regions of the Sun using a sequence of 200 LASCO/C2 images. This sequence was designed to study polar outflows in general, in both polar plumes and in interplume regions. The results of our analyses show that such studies are complicated by the existence of foreground material, especially when high latitude streamer material rotates into the field of view. We also describe our analysis of the kinematic properties of several polar jets. The results suggest that polar jets might be used for studies of the outflow wind velocities in coronal holes at heights above several solar radii. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Karovska, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 3 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 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 309 EP 312 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700059 ER PT S AU Kaghashvili, EK Esser, R AF Kaghashvili, EK Esser, R BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Density fluctuations in polar coronal holes: Mechanism and observational consequences SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID SOLAR-WIND; ALFVEN WAVES; ACCELERATION AB Recent Ultraviolet Coronagraph spectrometer observations (UVCS) indicate quasi-periodic variations in the polarized brightness in polar coronal holes. The importance of these observations arises from the fact that these fluctuations might be the signature of compressional waves at heliocentric distances of about 2 R.. Such observations are a clear indication that some kind of mechanism or mechanisms operate near the Sun transforming Alfven waves into compressible magnetosonic waves. In the present paper we investigate, whether a linear wave conversion of Alfven waves induced by velocity shear can explain the observations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kaghashvili, EK (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 10 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 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 341 EP 344 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700067 ER PT S AU Kaghashvili, EK AF Kaghashvili, EK BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Linear mechanism of Alfven wave dissipation induced by velocity shear: Phase mixing and damping SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID DISKS AB Alfven waves have been considered as candidates for coronal heating and solar wind acceleration since their presence was identified in situ solar wind. Unfortunately, because of the incompressible nature of these waves, difficulties are associated with their damping in a high temperature plasma. In this study, we discuss in detail the linear wave-conversion mechanism that can efficiently convert Alfven waves into other types of MI-ID waves. The phase mixing introduced by this mechanism is associated with inhomogeneous flow, in particular, with a velocity shear. To show how the mechanism might operate in different regions of the solar wind, we have considered three cases: A. beta = 0.133 (condition in coronal holes), B. beta = 1.2 (solar wind beyond the Alfvenic point) and C. beta = 4.8. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kaghashvili, EK (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 14 TC 2 Z9 2 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 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 345 EP 348 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700068 ER PT S AU Hu, YQ AF Hu, YQ BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Heating rates of solar wind ions by Alfven waves SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID HEAVY-IONS; ACCELERATION; ULYSSES AB Starting from the cold plasma dispersion relation of left-hand-polarized ion cyclotron waves propagating parallel to the external magnetic field in a multi-ion component plasma, the heating rate of each ion species is calculated for various parameters of the plasma properties and wave spectrum with implication to the heating of solar wind ions. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hu, YQ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 10 TC 7 Z9 7 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 365 EP 368 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700073 ER PT S AU Li, X Habbal, SR Hollweg, JV Esser, R AF Li, X Habbal, SR Hollweg, JV Esser, R BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Proton temperature anisotropy in the fast solar wind: Turbulence-driven dispersive ion cyclotron waves SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID CORONAL HOLES; VELOCITY DISTRIBUTIONS; TRANSITION REGION; ALFVEN WAVES; ACCELERATION; RESONANCE; PLASMAS; MODEL AB The effects of parallel propagating ion cyclotron waves on the solar wind plasma are investigated in an attempt to reproduce the observed proton temperature anisotropy. The model calculations presented here assume that a nonlinear cascade process, at the Kolmogorov rate, transports energy from low-frequency Alfven waves to the ion cyclotron resonant range. The energy is then picked up by the plasma through the resonant cyclotron interaction. Ion cyclotron waves are found to play an important role in shaping the proton temperature anisotropy starting in the inner corona and extending to interplanetary space. Dispersive ion cyclotron waves are able to cool protons more significantly than nondispersive ones. 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 23 TC 7 Z9 7 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 531 EP 534 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700114 ER PT S AU Wood, BE Karovska, M Chen, J Brueckner, GE Cook, JW Howard, RA AF Wood, BE Karovska, M Chen, J Brueckner, GE Cook, JW Howard, RA BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Comparing the kinematic properties of CMEs observed by LASCO and EIT with models of erupting flux ropes SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID CORONAL MASS EJECTION AB We present observations of three coronal mass ejections (CMEs) observed by the LASCO and EIT instruments aboard the Solar and Heliospheric Observatory. The three CMEs are from 1997 February 23, 1997 April 30, and 1998 March 6. The February 23 CME is accompanied by a spectacular prominence eruption and its leading edge reaches velocities of about 900 km s(-1). The April 30 and March 6 CMEs have no apparent accompanying prominence eruptions and attain more modest velocities of about 300 and 600 km s(-1), respectively. Despite their kinematic differences, all three CMEs have bright, roughly circular rims which can be interpreted as marking the apexes of expanding magnetic flux ropes, and all three can be tracked from their origins near the surface of the Sun out to great distances. We compare the kinematic and morphological properties of these CMEs with an MHD model of an erupting flux rope, and we find that. the CMEs can be successfully modeled in this manner. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Wood, BE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 6 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 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 633 EP 636 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700139 ER PT S AU Strachan, L Ciaravella, A Raymond, JC Fineschi, S O'Neal, R Kohl, JL Modigliani, A Noci, G Andrews, MD AF Strachan, L Ciaravella, A Raymond, JC Fineschi, S O'Neal, R Kohl, JL Modigliani, A Noci, G Andrews, MD BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Comparison of outflow velocity determinations with UVCS and LASCO for the coronal mass ejection of 13-14 August 1997 SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID SPECTROMETER; SOLAR AB The Ultraviolet Coronagraph Spectrometer (UVCS) on SOHO observed a Coronal Mass Ejection (CME) on 13-14 August 1997. The event was observed simultaneously with the LASCO white light coronographs. This paper describes the results from a comparison of outflow velocities determined from UVCS Doppler dimming studies with the velocities determined by examining the proper motions of the CME as measured by LASCO. In addition, estimates for line of sight velocities, densities and kinetic temperatures are discussed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Strachan, L (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 8 TC 2 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 637 EP 640 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700140 ER PT J AU Raymond, JC AF Raymond, JC TI Composition variations in the solar corona and solar wind SO SPACE SCIENCE REVIEWS LA English DT Review DE corona; solar wind; composition ID ELEMENT ABUNDANCES; CALCIUM ABUNDANCE; CHROMOSPHERE; REGION; FRACTIONATION; SPECTROMETER; DIFFUSION; PLASMAS; MODELS; YOHKOH AB Order of magnitude variations in relative elemental abundances are observed in the solar corona and solar wind. The instruments aboard SOHO make it possible to explore these variations in detail to determine whether they arise near the solar surface or higher in the corona. A substantial enhancement of low First Ionization Potential (FIP) elements relative to high FIP elements is often seen in both the corona and the solar wind, and that must arise in the chromosphere. Several theoretical models have been put forward to account for the FIP effect, but as yet even the basic physical mechanism responsible remains an open question. Evidence for gravitational settling is also found at larger heights in quiescent streamers. The question is why the heavier elements don't settle out completely. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 53 TC 30 Z9 30 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 55 EP 66 DI 10.1023/A:1005157914229 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000005 ER PT J AU Esser, R AF Esser, R TI Working group 3 report: Coronal hole boundaries and interactions with adjacent regions SO SPACE SCIENCE REVIEWS LA English DT Review DE coronal holes; streamer belt; fast and slow solar wind; coronal and interplanetary observations ID EXTENDED SOLAR CORONA; PLASMA-EXPERIMENT; WIND STREAM; SPECTROMETER; LATITUDE; VELOCITY; SPEED; ACCELERATION; SPECTROSCOPY; DEPENDENCE AB Summarized below are the discussions of working group 3 on "Coronal hole boundaries and interactions with adjacent regions" which took place at the 7th SOHO workshop in Northeast Harbor, Maine, USA, 28 September to 1 October 1998. A number of recent observational and theoretical results were presented during the discussions to shed light on different aspects of coronal hole boundaries. The working group also included presentations on streamers and coronal holes to emphasis the difference between the plasma properties in these regions, and to serve as guidelines for the definition of the boundaries. Observations, particularly white light observations, show that multiple streamers are present close to the solar limb at all times. At some distance from the sun, typically below 2 R-S, these streamers merge into a relatively narrow sheet as seen, for example, in LASCO and UVCS images. The presence of multiple current sheets in interplanetary space was also briefly addressed. Coronal hole boundaries were defined as the abrupt transition from the bright appearing plasma sheet to the dark coronal hole regions. Observations in the inner corona seem to indicate a transition of typically 10 to 20 degrees, whereas observations in interplanetary space, carried out from Ulysses, show on one hand an even faster transition of less than 2 degrees which is in agreement with earlier Hellos results. On the other hand, these observations also show that the transition happens on different scales, some of which are significantly larger. The slow solar wind is connected to the streamer belt/plasma sheet, even though the discussions were still not conclusive on the point where exactly the slow solar wind originates. Considered the high variability of plasma characteristics in slow wind streams, it seems most likely that several types of coronal regions produce slow solar wind, such as streamer stalks, streamer legs and open field regions between active regions, and maybe even regions just inside of the coronal holes. Observational and theoretical studies presented during the discussions show evidence that each of these regions may indeed contribute to the solar slow wind. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 50, Cambridge, MA 02138 USA. EM Resser@cfa.harvard.edu NR 45 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 93 EP 104 DI 10.1023/A:1005166116046 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000008 ER PT J AU Cranmer, SR Field, GB Kohl, JL AF Cranmer, SR Field, GB Kohl, JL TI Spectroscopic constraints on models of ion-cyclotron resonance heating in the polar solar corona SO SPACE SCIENCE REVIEWS LA English DT Review DE Alfven waves; corona; ion cyclotron resonance; spectroscopy; UV radiation ID ALFVEN WAVES; WIND IONS; ACCELERATION; SPECTROMETER; PLASMA; HOLE; SOHO AB Using empirical velocity distributions derived from UVCS and SUMER ultraviolet spectroscopy, we construct theoretical models of anisotropic ion temperatures in the polar solar corona. The primary energy deposition mechanism we investigate is the dissipation of high frequency (10-10000 Hz) ion-cyclotron resonant Alfven waves which can heat and accelerate ions differently depending on their charge and mass. We find that it is possible to explain the observed high perpendicular temperatures and strong anisotropies with relatively small amplitudes for the resonant waves. There is suggestive evidence for steepening of the Alfven wave spectrum between the coronal base and the largest heights observed spectroscopically. Because the ion-cyclotron wave dissipation is rapid, even for minor ions like O5+, the observed extended heating seems to demand a constantly replenished population of waves over several solar radii. This indicates that the waves are generated gradually throughout the wind rather than propagated up from the base of the corona. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 50, Cambridge, MA 02138 USA. EM scranmer@cfa.harvard.edu NR 22 TC 16 Z9 16 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 149 EP 152 DI 10.1023/A:1005142922406 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000016 ER PT J AU Dobrzycka, D Panasyuk, A Strachan, L Kohl, J AF Dobrzycka, D Panasyuk, A Strachan, L Kohl, J TI Comparison of polar and equatorial coronal holes observed by UVCS/SOHO: Geometry and physical properties SO SPACE SCIENCE REVIEWS LA English DT Review DE corona; coronal holes; solar wind; plasma physics; line profiles ID SOLAR-WIND AB We analyzed UVCS/SOHO data and compared the H I Ly alpha (121.6 nm) and O VI (103.2 nm,103.7 nm) emission in the polar and equatorial coronal holes. We found that the emission lines have similar characteristics in these two types of coronal holes. Both types show evidence for superradially diverging boundaries. The latitudinal distribution of the O VI line ratio may indicate that the equatorial coronal hole has O+5 outflow velocities lower than in the polar coronal holes. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Copernicus Astron Ctr, PL-00716 Warsaw, Poland. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 50, Cambridge, MA 02138 USA. EM ddobrzycka@cfa.harvard.edu NR 9 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 173 EP 176 DI 10.1023/A:1005163427858 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000022 ER PT J AU Dobrzycka, D Strachan, L Miralles, MP Kohl, JL Gardner, LD Smith, P AF Dobrzycka, D Strachan, L Miralles, MP Kohl, JL Gardner, LD Smith, P TI Variation of polar coronal hole profiles with solar cycle SO SPACE SCIENCE REVIEWS LA English DT Review DE corona; coronal holes; line profiles AB We compared the H I Ly alpha polar coronal hole profiles obtained during the three Spartan 201 flights (in 1993, 1994, and 1995) and during the more recent UVCS/SOHO mission. We found that at 2.1 R. there are no significant variations of the line shape over the several years of the descending phase of the solar cycle. However, there may be some evidence for the 1.8 R. profiles being broader towards solar minimum. The profiles at 2.1 R. are different from profiles obtained at 1.8 R.; they have clearly narrower cores and wide wings. We fitted the profiles with single and/or multiple Gaussian functions and calculated their typical 1/e half widths. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Copernicus Astron Ctr, PL-00716 Warsaw, Poland. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 50, Cambridge, MA 02138 USA. EM ddobrzycka@cfa.harvard.edu NR 7 TC 2 Z9 2 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 177 EP 180 DI 10.1023/A:1005171728767 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000023 ER PT J AU Frazin, RA Ciaravella, A Dennis, E Fineschi, S Gardner, LD Michels, J O'Neal, R Raymond, JC Wu, CR Kohl, JL Modigliani, A Noci, G AF Frazin, RA Ciaravella, A Dennis, E Fineschi, S Gardner, LD Michels, J O'Neal, R Raymond, JC Wu, CR Kohl, JL Modigliani, A Noci, G TI UVCS/SOHO ion kinetics in coronal streamers SO SPACE SCIENCE REVIEWS LA English DT Review ID SPECTROMETER AB We made streamer observations with the Ultraviolet Coronagraph Spectrometer (UVCS) on the Solar and Heliospheric Observatory (SOHO) during the early part of 1998, which was a time of moderate solar activity. We present an empirical study of coronal ion kinetics using the line profiles from these observations. Our first and most striking result is that the mid-latitude (ML) streamers have much narrower O VI 1032 Angstrom line profiles than the solar minimum equatorial (SME) streamers. Our second result is that the line profiles from a small collection of ions in ML streamers do not seem to be consistent with the ions having a single temperature and turbulent velocity. We discuss several interpretations, including line of sight (LOS) effects. This work is supported by the National Aeronautics and Space Administration under grant NAG-3192 to the Smithsonian Astrophysical Observatory. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florence, I-50125 Florence, Italy. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM rfrazin@cfa.harvard.edu RI Frazin, Richard/J-2625-2012 NR 8 TC 9 Z9 9 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 189 EP 192 DI 10.1023/A:1005184014654 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000026 ER PT J AU Karovska, M Wood, BE Cook, JW Howard, RA Brueckner, GE AF Karovska, M Wood, BE Cook, JW Howard, RA Brueckner, GE TI Study of dynamical properties of coronal structures in the polar regions SO SPACE SCIENCE REVIEWS LA English DT Review AB We present the results from a study of the dynamical properties of polar jets in the Sun's polar regions using LASCO C2 coronagraph and EIT observations. In the simplest impulsive acceleration scenarios for jets, gravity is expected to be the dominant force on the jet following the initial acceleration, especially in the Sun's polar regions where the open magnetic fields should not significantly impede the jet's motion. Our analysis shows that although at low heights the kinematics of the jets could be consistent with a gravitational deceleration of the ejected plasma, at higher heights their motions may simply follow the ambient solar wind outflow. If so, the polar jets can be used as tracers of the solar wind in coronal holes. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. USN, Res Lab, Washington, DC 20375 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 219 EP 222 DI 10.1023/A:1005100618288 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000032 ER PT J AU Ko, YK Groth, CPT AF Ko, YK Groth, CPT TI On the electron temperature and coronal heating in the fast solar wind constrained by in-situ observations SO SPACE SCIENCE REVIEWS LA English DT Review ID 1 AU; HOLE; DYNAMICS; MODEL AB The electron temperature profile in the polar coronal hole inferred by the ionic charge state data of the fast wind exhibits a local maximum of similar to 1.5 x 10(6) K. This indicates the existence of electron heating in the source region of the fast solar wind. In this paper, a two-fluid solar wind model, which incorporates additional 'mechanical' heating, is used to investigate the heating of the electrons in the coronal hole. We find that the classical collision-dominated description for the electron conduction heat flux is not valid and needs to be severely limited in order for the electron temperatures predicted by the model to agree with constraints supplied by both the solar wind ionic charge state data and the solar wind plasma properties observed at 1 AU. The corresponding constraints on the coronal electron heating will also be discussed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. RP NASA, Goddard Space Flight Ctr, Code 682-3, Greenbelt, MD 20771 USA. EM kuen@uvcs14.nascom.nasa.gov NR 18 TC 2 Z9 2 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 227 EP 231 DI 10.1023/A:1005104719197 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000034 ER PT J AU Kohl, JL Fineschi, S Esser, R Ciaravella, A Cranmer, SR Gardner, LD Suleiman, R Noci, G Modigliani, A AF Kohl, JL Fineschi, S Esser, R Ciaravella, A Cranmer, SR Gardner, LD Suleiman, R Noci, G Modigliani, A TI UVCS/SOHO observations of spectral line profiles in polar coronal holes SO SPACE SCIENCE REVIEWS LA English DT Review DE corona; solar wind; UV radiation; spectroscopy; line profiles ID VELOCITY DISTRIBUTIONS; SOLAR CORONA; SPECTROMETER AB Ultraviolet emission line profiles have been measured on 15-29 September 1997 for H I 1216 Angstrom, O VI 1032, 1037 Angstrom and Mg X 625 Angstrom in a polar coronal hole, at heliographic heights rho (in solar radii) between 1.34 and 2.0. Observations of H I 1216 Angstrom and the O VI doublet from January 1997 for rho = 1.5 to 3.0 are provided for comparison. Mg X 625 Angstrom is observed to have a narrow component at rho = 1.34 which accounts for only a small fraction of the observed spectral radiance, and a broad component that exists at all observed heights. The widths of O VI broad components are only slightly larger than those for H I at rho = 1.34, but are significantly larger at rho = 1.5 and much larger for rho > 1.75. In contrast, the Mg X values are less than those of H I up to 1.75 and then increase rapidly up to at least rho = 2.0, but never reach the values of O VI. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florence, I-50125 Florence, Italy. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 50, Cambridge, MA 02138 USA. EM jkohl@cm.harvard.edu NR 9 TC 20 Z9 20 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 233 EP 236 DI 10.1023/A:1005156703267 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000035 ER PT J AU Li, X AF Li, X TI A 16-moment fast solar wind model SO SPACE SCIENCE REVIEWS LA English DT Review ID PHYSICAL-PROPERTIES; TEMPERATURE; IONS AB A 16-moment fast solar wind model based on a bi-Maxwellian velocity distribution is presented. Although the proton heat flux density is found to be significantly smaller than the classical Spitzer-Harm value, it still plays a significant role in shaping the proton temperature anisotropy in the fast solar wind. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 253 EP 256 DI 10.1023/A:1005117021923 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000040 ER PT J AU Maccari, L Noci, G Fineschi, S Modigliani, A Romoli, M Kohl, JL AF Maccari, L Noci, G Fineschi, S Modigliani, A Romoli, M Kohl, JL TI Ly-alpha observation of a coronal streamer with UVCS/SOHO SO SPACE SCIENCE REVIEWS LA English DT Review ID SPECTROMETER; SOLAR AB In this paper we discuss some characteristics of an equatorial streamer observed by UVCS in July 1997. We determine the height distribution of the Ly-alpha total intensity and of its width. We focus our attention, in particular, on the time variability of these parameters. C1 Univ Florence, Dipartimento Astron & Sci Spazio, I-50121 Florence, Italy. Osserv Astron Torino, I-10025 Pino Torinese, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Univ Florence, Dipartimento Astron & Sci Spazio, I-50121 Florence, Italy. RI Romoli, Marco/H-6859-2012 NR 7 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 265 EP 268 DI 10.1023/A:1005173106902 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000043 ER PT J AU Miralles, MP Strachan, L Gardner, LD Smith, PL Kohl, JL Guhathakurta, M Fisher, RR AF Miralles, MP Strachan, L Gardner, LD Smith, PL Kohl, JL Guhathakurta, M Fisher, RR TI Properties of coronal hole/streamer boundaries and adjacent regions as observed by Spartan 201 SO SPACE SCIENCE REVIEWS LA English DT Review ID EXTENDED SOLAR CORONA; WIND; STREAMERS; ORIGINS AB The Spartan 201 flights from 1993 to 1995 provided us with observations in H I Lyman-alpha of several coronal hole/streamer boundaries and adjacent streamers during the declining phase of the current solar cycle. Analysis of the latitudinal dependence of the line intensities clearly shows that there is a boundary region at the coronal hole/streamer interface where the H I Lyman-alpha intensity reaches a minimum value. Similar results are also found in UVCS/SOHO observations. We also discuss differences in the coronal hole/streamer boundaries for different types of streamers and their changes over the three year period of Spartan 201 observations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 50, Cambridge, MA 02138 USA. EM mmiralles@cfa.harvard.edu NR 13 TC 4 Z9 4 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 277 EP 281 DI 10.1023/A:1005177207810 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000045 ER PT J AU Ofman, L Romoli, M Noci, G Poletto, G Kohl, JL Howard, RA St Cyr, C Deforest, CE AF Ofman, L Romoli, M Noci, G Poletto, G Kohl, JL Howard, RA St Cyr, C Deforest, CE TI SOHO observations of density fluctuations in coronal holes SO SPACE SCIENCE REVIEWS LA English DT Review ID SOLAR-WIND ACCELERATION; SOLITARY WAVES; SPECTROMETER AB In recent UVCS/SOHO White Light Channel (WLC) observations we found quasi-periodic variations in the polarized brightness (pB) in the polar coronal holes at heliocentric distances of 1.9 to 2.45 solar radii. The motivation for the observation is the 2.5D MHD model of solar wind acceleration by nonlinear waves, that predicts compressive fluctuations in coronal holes. in February 1998 we performed new observations using the UVCS/WLC in the coronal hole and obtained additional data. The new data corroborate our earlier findings with higher statistical significance. The new longer observations show that the power spectrum peaks in the 10-12 minute range. These timescales agree with EIT observations of brightness fluctuations in polar plumes. We performed preliminary LASCO/C2 observations in an effort to further establish the coronal origin of the fluctuations. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Raytheon ITSS, Greenbelt, MD 20771 USA. Univ Florence, Dept Astron, I-50125 Florence, Italy. Osserv Astrofis Arcetri, I-50125 Florence, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. USN, Res Lab, Washington, DC 20375 USA. Stanford Univ, Stanford, CA 94305 USA. RP NASA, Goddard Space Flight Ctr, Code 682, Greenbelt, MD 20771 USA. RI Romoli, Marco/H-6859-2012 NR 9 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 287 EP 290 DI 10.1023/A:1005181408719 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000047 ER PT J AU Strachan, L Ko, YK Panasyuk, AV Dobrzycka, D Kohl, JL Romoli, M Noci, G Gibson, SE Biesecker, DA AF Strachan, L Ko, YK Panasyuk, AV Dobrzycka, D Kohl, JL Romoli, M Noci, G Gibson, SE Biesecker, DA TI Constraints on coronal outflow velocities derived from UVCS Doppler dimming measurements and in-situ charge state data SO SPACE SCIENCE REVIEWS LA English DT Review DE corona; solar wind; UV radiation; spectroscopy; line profiles ID HOLE AB We constrain coronal outflow velocity solutions, resolved along the line-of-sight, by using Doppler dimming models of H I Lyman alpha and O VI 1032/1037 Angstrom emissivities obtained with data from the Ultraviolet Coronagraph Spectrometer (UVCS) on SOHO. The local emissivities, from heliocentric heights of 1.5 to 3.0 solar radii, were determined from 3-D reconstructions of line-of-sight intensities obtained during the first Whole Sun Month Campaign (10 August to 8 September 1996). The models use electron densities derived from polarized brightness measurements made with the visible light coronagraphs on UVCS and LASCO, supplemented with data from Mark III at NCAR/MLSO. Electron temperature profiles are derived from 'freezing-in' temperatures obtained from an analysis of charge state data from SWICS/Ulysses. The work concentrates on neutral hydrogen outflow velocities which depend on modeling the absolute coronal H I Ly alpha emissivities. We use an iterative method to determine the neutral hydrogen outflow velocity with consistent values for the electron temperatures derived from a freezing-in model. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florence, I-50125 Florence, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Catholic Univ Amer, Washington, DC 20064 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 50, Cambridge, MA 02138 USA. EM lstrachan@cfa.harvard.edu RI Gibson, Sarah/A-9189-2011; Romoli, Marco/H-6859-2012 NR 7 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 311 EP 314 DI 10.1023/A:1005193711445 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000053 ER PT J AU Suess, ST Poletto, G Corti, G Simnett, G Noci, G Romoli, M Kohl, J Goldstein, B AF Suess, ST Poletto, G Corti, G Simnett, G Noci, G Romoli, M Kohl, J Goldstein, B TI Ulysses-UVCS coordinated observations SO SPACE SCIENCE REVIEWS LA English DT Review DE SOHO; Ulysses; streamers AB We present results from SOHO/UVCS measurements of the density and flow speed of plasma at the Sun and again of the same plasma by Ulysses/SWOOPS in the solar wind. UVCS made measurements at 3.5 and 4.5 solar radii and Ulysses was at 5.1 AU. Data were taken for nearly 2 weeks in May-June 1997 at 9-10 degrees north of the equator in the streamer belt on the east limb. Density and flow speed were compared to see if near Sun characteristics are preserved in the interplanetary medium. By chance, Ulysses was at the very northern edge of the streamer belt. Nevertheless, no evidence was found of fast wind or mixing of slow wind with fast wind coming from the northern polar coronal hole. The morphology of the streamer belt was similar at the beginning and end of the observing period, but was markedly different during the middle of the period. A corresponding change in density (but not flow speed) was noted at Ulysses. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Osserv Astrofis Arcetri, I-50125 Florence, Italy. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Florence, I-50121 Florence, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP NASA, George C Marshall Space Flight Ctr, Mail Stop ES82, Huntsville, AL 35812 USA. RI Romoli, Marco/H-6859-2012 NR 2 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 319 EP 322 DI 10.1023/A:1005197812354 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000055 ER PT J AU Suleiman, RM Kohl, JL Panasyuk, AV Ciaravella, A Cranmer, SR Gardner, LD Frazin, R Hauck, R Smith, PL Noci, G AF Suleiman, RM Kohl, JL Panasyuk, AV Ciaravella, A Cranmer, SR Gardner, LD Frazin, R Hauck, R Smith, PL Noci, G TI UVCS/SOHO observations of HI Lyman alpha line profiles in coronal holes at heliocentric heights above 3.0 R-circle dot SO SPACE SCIENCE REVIEWS LA English DT Review DE corona; coronal holes; solar wind; UV radiation; spectroscopy; line profiles ID NEUTRAL HYDROGEN; SOLAR-WIND; SPECTROMETER AB The Ultraviolet Coronagraph Spectrometer (UVCS) on the Solar and Heliospheric Observatory (SOHO) has been used to measure spectral line profiles for H I Ly alpha in the south polar coronal hole at projected heliocentric heights from 3.5 to 6.0 R. during 1998 January 5-11. Observations from 1.5 to 2.5 R. were made for comparison. The H I Ly alpha profile is the only one observable with UVCS above 3.5 Ro in coronal holes. Within this region the outflowing coronal plasma becomes nearly collisionless and the ionization balance is believed to become frozen. In this paper, the 1/e half widths of the coronal velocity distributions are provided for the observed heights. The velocity distributions include all motions contributing to the velocities along the line of sight (LOS). The observations have been corrected for instrumental effects and interplanetary H I Ly alpha. The half widths were found to increase with projected heliographic height from 1.5 to 2.5 R. and decrease with height from 3.5 to 5 R.. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florence, I-50125 Florence, Italy. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM rsuleiman@cfa.harvard.edu RI Frazin, Richard/J-2625-2012 NR 11 TC 7 Z9 7 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 327 EP 330 DI 10.1023/A:1005102013262 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000057 ER PT J AU Vasquez, AM Raymond, JC Van Ballegooijen, AA AF Vasquez, AM Raymond, JC Van Ballegooijen, AA TI UVCS observations and modeling of streamers SO SPACE SCIENCE REVIEWS LA English DT Review ID ULTRAVIOLET CORONAGRAPH SPECTROMETER AB We present results derived from the analysis of an equatorial streamer structure as observed by the UVCS instrument aboard SOHO. From observations of the H I Ly alpha and Ly beta lines we infer the density and temperature of the plasma. We develop a preliminary axisymmetric, magnetostatic model of the corona which includes the effects of gas pressure gradients on the magnetic structure. We infer a coronal plasma beta > 1 in the closed field regions and near the cusp of the streamer. We add to the model a parallel velocity field assuming mass flux conservation along magnetic flux tubes. We then compute the Ly alpha emissivity and the line-of-sight integrals to obtain images of Ly alpha intensity, taking into account projection effects and Doppler dimming. The images we obtain from this preliminary model are in good general agreement with the UVCS observations, both qualitatively and quantitatively. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St MS 15, Cambridge, MA 02138 USA. EM avasquez@cfa.harvard.edu NR 7 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 335 EP 338 DI 10.1023/A:1005106131009 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000059 ER PT J AU Young, PR Esser, R AF Young, PR Esser, R TI Comparing quiet Sun and coronal hole regions with CDS/SOHO SO SPACE SCIENCE REVIEWS LA English DT Review DE coronal hole; quiet Sun; density; temperature AB Spectra from the Coronal Diagnostic Spectrometer on board SOHO are used to compare density and temperature in coronal hole and quiet Sun regions. C1 Univ Cambridge, Dept Appl Math & Theoret Phys, Cambridge CB3 9EW, England. Smithsonian Astrophys Observ, Cambridge, MA USA. RP Univ Cambridge, Dept Appl Math & Theoret Phys, Silver St, Cambridge CB3 9EW, England. NR 5 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 1999 VL 87 IS 1-2 BP 345 EP 348 DI 10.1023/A:1005166417805 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239YL UT WOS:000082798000061 ER PT S AU Lorenzini, EC Estes, RD Cosmo, ML Pelaez, J AF Lorenzini, EC Estes, RD Cosmo, ML Pelaez, J BE Bishop, RH Mackison, DL Culp, RD Evans, MJ TI Dynamical, electrical and thermal coupling in a new class of electrodynamic tethered satellites SO SPACEFLIGHT MECHANICS 1999, VOL 102, PTS I AND II SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 9th Annual Space Flight Mechanics Meeting CY FEB 07-10, 1999 CL BRECKENRIDGE, CO SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB A new class of electrodynamic tethers have been recently introduced which provide comparatively high tether currents with relatively short and light tethers. These space systems make use of a bare tether (anode) to collect electrons from the ionosphere rather than the less efficient, conductive, large spherical termination flown in the past. This new technology, which is suitable for propellantless transportation in the ionosphere, will be demonstrated in August 2000 when the Propulsive Small Expendable Deployment System (ProSEDS) will attempt to deorbit a Delta second stage by using electrodynamic forces. This class of space systems exhibits a strong coupling among the dynamical, electrical, and thermal responses that must be analyzed with computer codes that model the tether continuum dynamics, electrodynamics, and thermal behavior in an integrated manner. After introducing briefly the physics of bare tethers and electron collection from the ionosphere, the paper describes the models adopted to simulate a bare-tether system. Then, it discusses simulation results for selected cases, pertinent to ProSEDS, which show the inter-dependencies among the system parameters. Specifically, the paper shows that key electrical, thermal, and dynamic parameters can strongly affect the decay rate (the most relevant performance index for the system under analysis) and also the system stability. An appropriate choice of system parameters can produce a sustainable electrodynamic drag force capable of increasing, by more than an order of magnitude, the natural decay rate of the Delta stage with a tether mass of only 12 kg and a stabilizing mass of 20 kg. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Lorenzini, EC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 6 TC 8 Z9 8 U1 0 U2 3 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-458-3 J9 ADV ASTRONAUT SCI PY 1999 VL 102 BP 1333 EP 1344 PN 1&2 PG 12 WC Engineering, Aerospace SC Engineering GA BN45R UT WOS:000081956900082 ER PT B AU Pahre, MA Djorgovski, SG de Carvalho, RR AF Pahre, MA Djorgovski, SG de Carvalho, RR BE Cepa, J Carral, P TI Systematic variations in age and metallicity along the early-type galaxy sequence SO STAR FORMATION IN EARLY-TYPE GALAXIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Meeting on Star Formation in Early-Type Galaxies CY JUN 29-JUL 03, 1998 CL GUANAJUATO, MEXICO SP Astron Soc Pacific ID FUNDAMENTAL PLANE; ELLIPTIC GALAXIES; EVOLUTION; CLUSTER; PROFILES AB The form of the early-type galaxy scaling relation (the Fundamental Plane or FP) is a direct indicator of the underlying physical origins for the galaxy sequence. Observed properties of the FP include: (1) the slope increases with wavelength; (2) the slope deviates from the virial expectation (assuming homology and constant M/L) at all wavelengths; (3) the intercept evolves passively with redshift; and (4) the slope decreases slowly with redshift. The first property implies that stellar populations contribute to the slope of the FP, the second and fourth properties exclude metallicity effects as the sole cause of the slope, and the third implies that the stellar content of the "average" early-type galaxy formed at high redshift. A composite model-including variations in age and metallicity, as well as a wavelength-independent effect such as homology breaking-is presented which can fit all four observed properties. This model implies that the most luminous early-type galaxies contain the oldest and most metal-rich stars, while the lowest luminosity galaxies formed the bulk of their stars as recently at z(f) similar to 1. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Pahre, MA (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NR 33 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 1-886733-84-8 J9 ASTR SOC P PY 1999 VL 163 BP 17 EP 27 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN27V UT WOS:000081412300002 ER PT B AU Pahre, MA AF Pahre, MA BE Cepa, J Carral, P TI Eight tests of hierarchical galaxy formation models using the observed properties of elliptical galaxies SO STAR FORMATION IN EARLY-TYPE GALAXIES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Meeting on Star Formation in Early-Type Galaxies CY JUN 29-JUL 03, 1998 CL GUANAJUATO, MEXICO SP Astron Soc Pacific ID EVOLUTION; CLUSTERS AB The observed properties of elliptical galaxies are compared to the predictions of models of hierarchical galaxy formation. While the models can explain some of the observed properties, the success of the models in producing a color-magnitude relation (dependence of stellar MIL on luminosity) while failing to produce the wavelength dependence of the slope of the Fundamental Plane correlations (dependence of stellar hilt on mass) implies that there are subtle problems underlying the star formation feedback prescriptions used in the models. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Pahre, MA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 16 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 1-886733-84-8 J9 ASTR SOC P PY 1999 VL 163 BP 283 EP 285 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN27V UT WOS:000081412300035 ER PT B AU Kuraszkiewicz, J Wilkes, BJ Green, PJ Mathur, S McDowell, JC AF Kuraszkiewicz, J Wilkes, BJ Green, PJ Mathur, S McDowell, JC BE Gaskell, CM Brandt, WN Dietrich, M DultzinHacyan, D Eracleous, M TI SEDs vs. emission-line correlations in low redshift quasars SO STRUCTURE AND KINEMATICS OF QUASAR BROAD LINE REGIONS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Meeting on Structure and Kinematics of Quasar Broad Line Regions CY MAR 23-26, 1998 CL LINCOLN, NE SP Astron Soc Pacific ID ACTIVE GALACTIC NUCLEI; BALDWIN; EXTINCTION; DISKS AB We investigate the relations between the observed emission Line strengths, widths and continuum properties of a sample of low redshift quasars for which contemporaneous IR-soft-X-ray spectral energy distributions (SEDs) are available. This includes investigating correlations between optical/UV lines with both the luminosity and the shape of the quasars' continua, as well as correlations between the various Lines. Our data do not favor a model in which changes in continuum shape (due to e.g., the ionization parameter decreasing with luminosity) cause the "Baldwin effect". The data can instead be explained by an accretion disk (AD) model in which Limb darkening and the projected surface area of an optically thick, geometrically thin disk combine to cause a viewing-angle dependent apparent opt./UV luminosity and a more isotropic X-ray luminosity. The scatter in our correlations is larger than that expected from this AD model, suggesting the presence of dust, which reddens both the continuum and the broad emission Lines. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kuraszkiewicz, J (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 12 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 1-886733-97-X J9 ASTR SOC P PY 1999 VL 175 BP 235 EP 240 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP16L UT WOS:000084260300032 ER PT B AU Wilkes, BJ Mathur, S Fiore, F Antonelli, A AF Wilkes, BJ Mathur, S Fiore, F Antonelli, A BE Gaskell, CM Brandt, WN Dietrich, M DultzinHacyan, D Eracleous, M TI SAX observations of the maser AGN ESO103-G35. SO STRUCTURE AND KINEMATICS OF QUASAR BROAD LINE REGIONS SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT Meeting on Structure and Kinematics of Quasar Broad Line Regions CY MAR 23-26, 1998 CL LINCOLN, NE SP Astron Soc Pacific ID ACTIVE GALAXIES; RAY-SPECTRUM; ABSORPTION; NGC-4258 AB We have made SAX observations of the Seyfert 2 galaxy ESO103-G35, which contains a nuclear maser source and is known to be heavily absorbed in the X-rays. We present preliminary analysis of the X-ray spectrum which extends up to similar to 200 keV with a spectral index alpha(E) = 0.95 +/- 0.06 (F(nu) alpha nu(-alpha E)). This hard X-ray spectrum is typical of Seyfert galaxies. The strong soft X-ray absorption has a column density, N(H) of 2.0 +/- 0.1 x 10(23) cm(-2) consistent with earlier results. The spectrum also shows a cold (E = 6.4 +/- 0.1 keV, rest frame), narrow (FWHM < 23 x 10(3) km s(-1)) Fe K alpha Line whose strength, energy and width are consistent with fluorescence in the neutral absorber. The continuum flux decreased by similar to 40% between the two parts of this observation, October 1996 and October 1997, with no significant change in spectral index or absorption column density. The equivalent width of Fe K alpha was 238 +/- 60 in 1996 and 340 +/- 100 keV in 1997, consistent with a constant Line flux which would imply a Line emitting region greater than or similar to 1 light year. C1 Harvard Smithsonian Ctr Astrophys, Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Wilkes, BJ (reprint author), Harvard Smithsonian Ctr Astrophys, Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. EM belinda@cfa.harvard.edu NR 18 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 1-886733-97-X J9 ASTR SOC P PY 1999 VL 175 BP 395 EP 400 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP16L UT WOS:000084260300056 ER PT J AU Grissom, CA Charola, AE Boulton, A Mecklenburg, MF AF Grissom, CA Charola, AE Boulton, A Mecklenburg, MF TI Evaluation over time of an ethyl silicate consolidant applied to ancient lime plaster SO STUDIES IN CONSERVATION LA English DT Article C1 Smithsonian Inst, Mus Support Ctr, SMCRE, Washington, DC 20560 USA. RP Grissom, CA (reprint author), Smithsonian Inst, Mus Support Ctr, SMCRE, MRC 534, Washington, DC 20560 USA. NR 21 TC 7 Z9 9 U1 0 U2 2 PU MANEY PUBLISHING PI LEEDS PA STE 1C, JOSEPHS WELL, HANOVER WALK, LEEDS LS3 1AB, W YORKS, ENGLAND SN 0039-3630 EI 2047-0584 J9 STUD CONSERV JI Stud. Conserv. PY 1999 VL 44 IS 2 BP 113 EP 120 DI 10.2307/1506723 PG 8 WC Archaeology; Art; Chemistry, Applied; Chemistry, Analytical; Spectroscopy SC Archaeology; Art; Chemistry; Spectroscopy GA 209FF UT WOS:000081037000005 ER PT S AU Manthorne, KE AF Manthorne, KE BE Carter, EC TI Legible landscapes - Text and image in the expeditionary art of Frederic Church SO SURVEYING THE RECORD: NORTH AMERICAN SCIENTIFIC EXPLORING TO 1930 SE MEMOIRS OF THE AMERICAN PHILOSOPHICAL SOCIETY LA English DT Proceedings Paper CT Conference on Surveying the Record - North American Scientific Exploration to 1900 CY MAR 14, 1997 CL PHILADELPHIA, PA SP Lib Amer Philosoph Soc C1 Natl Museum Art, Smithsonian Inst, Washington, DC USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER PHILOSOPHICAL SOC PI PHILADELPHIA PA INDEPENDENCE SQUARE, PO BOX 40227-5227, PHILADELPHIA, PA 19106 USA SN 0065-9738 BN 0-87169-231-7 J9 MEM A PHILO PY 1999 VL 231 BP 133 EP 145 PG 13 WC History SC History GA BN62F UT WOS:000082366100008 ER PT J AU Richardson, SL Rutzler, K AF Richardson, SL Rutzler, K TI Bacterial endosymbionts in the agglutinating foraminiferan Spiculidendron corallicolum Rutzler and Richardson, 1996 SO SYMBIOSIS LA English DT Article DE Astrorhizidae; bacterial endosymbionts; Belize; endosymbiosis; foraminiferans ID MARINE NITRIFYING BACTERIA; PLANKTIC FORAMINIFERA; DEOXYRIBONUCLEIC-ACID; OXIDIZING BACTERIA; MANGANESE NODULES; SYMBIOSIS; PHOTOINHIBITION; ULTRASTRUCTURE; INVERTEBRATES; EVOLUTION AB The cytoplasm of the Caribbean agglutinating foraminiferan Spiculidendron corallicolum Rutzler and Richardson, 1996, consistently contains gram-negative, non-photosynthetic bacteria that show ultrastructural similarities to marine nitrifying bacteria. In some micrographs, bacteria occur in densities as high as 21 cells per 60 mu m(3) of cytoplasm, indicating that an individual foraminiferan may contain as many as 2.2 x 10(9) bacterial endosymbionts. The bacteria are free-living in the cytoplasm, spherical to ovoidal in shape (similar to 0.6 x 0.7 mu m), and devoid of extracellular structures. UItrastructurally, the bacteria are characterized by a discrete fibrillar nucleoid, a carboxysome-like electron dense inclusion (100 nm), and intracytoplasmic lamellae (100 nm x length of the cell). The presence of dividing individuals within the cytoplasm and the absence of this group within the foraminiferans' digestive vacuoles, indicate that the bacteria are endosymbionts and not ingested food organisms. The discovery of prokaryotic endosymbionts in what has been considered to be a basal foraminiferal clade, indicates that endosymbiosis may have played a more significant role in the evolution and diversification of foraminiferans than has previously been suspected. C1 Yale Univ, Dept Ecol & Evolutionary Biol, New Haven, CT 06540 USA. Smithsonian Inst, Natl Museum Amer Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Richardson, SL (reprint author), Woods Hole Oceanog Inst, Dept Geol & Geophys, MS 08, Woods Hole, MA 02543 USA. NR 66 TC 12 Z9 12 U1 0 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0334-5114 J9 SYMBIOSIS JI Symbiosis PY 1999 VL 26 IS 4 BP 299 EP 312 PG 14 WC Microbiology SC Microbiology GA 218RV UT WOS:000081566200001 ER PT B AU Reid, MJ AF Reid, MJ BE Taylor, GB Carilli, CL Perley, RA TI Spectral line VLBI SO SYNTHESIS IMAGING IN RADIO ASTRONOMY II SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 6th Summer School Conference on Synthesis Imaging in Radio Astronomy II CY JUN 17-23, 1998 CL SOCORRO, NM SP Natl Radio Astronom Observat, New Mexico Inst Mining & Technol AB Spectral line VLBI observations of cosmic sources of maser emission have contributed some spectacular astronomical results. This chapter covers basic concepts of spectral line VLBI data analysis. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Reid, MJ (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 1-58381-005-6 J9 ASTR SOC P PY 1999 VL 180 BP 481 EP 497 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN98M UT WOS:000083761000025 ER PT J AU Nepokroeff, M Bremer, B Sytsma, KJ AF Nepokroeff, M Bremer, B Sytsma, KJ TI Reorganization of the genus Psychotria and tribe Psychotrieae (Rubiaceae) inferred from ITS and rbcL sequence data SO SYSTEMATIC BOTANY LA English DT Article ID NUCLEAR RIBOSOMAL DNA; TUBEROUS EPIPHYTES; REVISION; PHYLOGENY; ONAGRACEAE AB Psychotria is one of the largest genera of angiosperms as currently delimited, with approximately 1650 species estimated worldwide. A molecular phylogenetic study was undertaken using ITS and rbcL sequence data to address the generic circumscription of Psychotria and its allies in the tribe Psychotrieae and to compare traditional subgeneric groupings with relationships inferred from phylogenetic analysis. ITS sequences from 85 taxa were sampled representing the genus Psychotria and members of the tribe Psychotrieae, with Gaertnera and Mitchella used as outgroups. Sequences from the rbcL gene were analyzed for a subset of these taxa, plus genera in the closely related tribes Coussareae, Morindeae, Ophiorrhizeae, and others. Our results suggest that Psychotria is broadly paraphyletic and defined by lack of characters used to define other genera in the tribe. Two groups formerly assigned to Psychotria (sect. Notopleura and subg. Heteropsychotria plus Palicourea) are more closely related to other genera in the Psychotrieae than they are to other species of Psychotria. In addition, subg. Psychotria includes species formerly assigned to the Malesian epiphytic myrmecophytes of subtribe Hydnophytinae. We propose that the genus Psychotria be restricted to include subg. Psychotria, subg. Tetramerae, and members of the subtribe Hydnophytinae. C1 Smithsonian Inst, Lab Mol Systemat, MRC 534, MSC, Washington, DC 20560 USA. Uppsala Univ, Dept Systemat Bot, S-75236 Uppsala, Sweden. Univ Wisconsin, Dept Bot, Madison, WI 53706 USA. RP Nepokroeff, M (reprint author), Smithsonian Inst, Lab Mol Systemat, MRC 534, MSC, Washington, DC 20560 USA. NR 67 TC 102 Z9 115 U1 1 U2 4 PU AMER SOC PLANT TAXONOMISTS PI BRONX PA NEW YORK BOTANICAL GARDEN, BRONX, NY 10458-5126 USA SN 0363-6445 J9 SYST BOT JI Syst. Bot. PD JAN-MAR PY 1999 VL 24 IS 1 BP 5 EP 27 DI 10.2307/2419383 PG 23 WC Plant Sciences; Evolutionary Biology SC Plant Sciences; Evolutionary Biology GA 219FJ UT WOS:000081597000002 ER PT J AU Swanson, WF McRae, MA Wildt, DE Rall, WF AF Swanson, WF McRae, MA Wildt, DE Rall, WF TI Cryoprotectant toxicity and cryopreservation success in IVF-derived domestic cat embryos after embryo transfer SO THERIOGENOLOGY LA English DT Meeting Abstract C1 Cincinnati Zoo & Bot Garden, Ctr Res Endangered Wildlife, Cincinnati, OH USA. Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA USA. NIH, Natl Ctr Res Resources, Bethesda, MD 20892 USA. RI Rall, William/C-5104-2008 NR 0 TC 12 Z9 13 U1 1 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0093-691X J9 THERIOGENOLOGY JI Theriogenology PD JAN 1 PY 1999 VL 51 IS 1 BP 174 EP 174 DI 10.1016/S0093-691X(99)91733-8 PG 1 WC Reproductive Biology; Veterinary Sciences SC Reproductive Biology; Veterinary Sciences GA 154AM UT WOS:000077865900034 ER PT J AU Spindler, RE Wildt, DE AF Spindler, RE Wildt, DE TI Relationship of substrate metabolism to cat oocyte maturation SO THERIOGENOLOGY LA English DT Meeting Abstract C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0093-691X J9 THERIOGENOLOGY JI Theriogenology PD JAN 1 PY 1999 VL 51 IS 1 BP 295 EP 295 DI 10.1016/S0093-691X(99)91854-X PG 1 WC Reproductive Biology; Veterinary Sciences SC Reproductive Biology; Veterinary Sciences GA 154AM UT WOS:000077865900155 ER PT S AU Gardner, L Kohl, J Cranmer, S Fineschi, S Golub, L Raymond, J Smith, PL Strachan, L Howard, R Moses, D Socker, D Wang, D Fisher, RR Davila, J St Cyr, C Noci, G Romoli, M Tondello, G Naletto, G Nicolosi, P Poletto, L AF Gardner, L Kohl, J Cranmer, S Fineschi, S Golub, L Raymond, J Smith, PL Strachan, L Howard, R Moses, D Socker, D Wang, D Fisher, RR Davila, J St Cyr, C Noci, G Romoli, M Tondello, G Naletto, G Nicolosi, P Poletto, L BE Fineschi, S Woodgate, BE Kimble, RA TI The Advanced Solar Coronal Explorer mission (ASCE) SO ULTRAVIOLET AND X-RAY DETECTION, SPECTROSCOPY, AND POLARIMETRY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultraviolet and X-Ray Detection, Spectroscopy, and Polarimetry III CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE EUV spectroscopy; polarimetry; corona; space missions ID ULTRAVIOLET AB The Advanced Solar Coronal Explorer (ASCE) is one of five missions selected for a Phase A Concept Study in the current round of proposed MIDEX missions. ASCE's instrument complement is supported by a SPARTAN 400 reusable carrier. The spacecraft is carried into orbit and deployed by the Space Shuttle; at mission's end, nominally 2 years later, it is retrieved and returned to earth for post-flight calibration. ASCE comprises two instrument modules, the Spectroscopic and Polarimetric Coronagraph (SPC) and the Extreme Ultraviolet Imager (EUVI). The external occulter for the coronagraph is supported on a boom, which is extended 10 meters beyond the instrument apertures once the spacecraft is on station. Large aperture optics can therefore be used, and this, in combination with improvements in optical and photon detection efficiencies, will provide spectroscopy of the extended solar corona with unprecedented sensitivity and spatial resolution, routine measurements of the electron temperature, and polarimetry of the H I Lyman lines. SPC also extends the short wavelength limit to 28 nm. As a consequence, SPC will be able to perform the first He II 30.4 nm and He I 58.3 nm spectroscopy of the extended corona. In the visible part of the spectrum (450-600 nm), SPC's Large Aperture Spectroscopic Coronagraph (LASCO) channel will provide polarimetric images with 1.8 are second resolution elements, which will allow the determination of polarized brightness of the coronal plasma. In a separate parallel channel LASCO will also provide images at single minor ion line wavelengths from which can be determined the shapes and Doppler shifts of those lines. The distant external occulter provides for major improvement in stray light suppression. The EUVI instrument will take high cadence images of the full disk and low corona at four selectable wavelengths with 0.9 are second resolution elements. A description of the instrument design and performance capabilities is presented. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gardner, L (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Woodgate, Bruce/D-2970-2012; Romoli, Marco/H-6859-2012; Naletto, Giampiero/S-6329-2016 OI Naletto, Giampiero/0000-0003-2007-3138 NR 12 TC 10 Z9 10 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 0-8194-3250-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3764 BP 134 EP 146 DI 10.1117/12.371095 PG 13 WC Engineering, Aerospace; Astronomy & Astrophysics; Optics SC Engineering; Astronomy & Astrophysics; Optics GA BP33T UT WOS:000084756600014 ER PT S AU Fineschi, S Gardner, LD Kohl, JL Romoli, M Pace, E Corti, G Noci, G AF Fineschi, S Gardner, LD Kohl, JL Romoli, M Pace, E Corti, G Noci, G BE Fineschi, S Woodgate, BE Kimble, RA TI Polarimetry of the UV solar corona with ASCE SO ULTRAVIOLET AND X-RAY DETECTION, SPECTROSCOPY, AND POLARIMETRY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultraviolet and X-Ray Detection, Spectroscopy, and Polarimetry III CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE UV space optics; UV spectroscopy; UV polarimetry ID ULTRAVIOLET AB The Advanced Solar Coronal Explorer (ASCE) is a mid-explorer (MidEx) mission selected, together with other five, for the a Phase A Concept Study in the 1999 round of MidEx proposal. ASCE's spacecraft bus is a SPARTAN 400 reusable carrier deployed in low Earth orbit by the Space Shuttle. ASCE's payload comprises two instrument modules, the Spectroscopic and Polarimetric Coronagraph (SPC) and the Extreme Ultravoilet Imager (EUVI). The scientific objective of the mission is the investigation, through spectroscopic and polarimetric techniques, of the physics of the coronal heating and of the solar wind acceleration. A critical physical parameter of the corona is the magnetic field. Polarimetric measurements of UV coronal radiation and their interpretation through the Hanle effect can be used for coronal magnetic field diagnostics. One of the SPC spectrometers, the Spectroscopy/Polarimetry channel (SPCH), includes a reflecting Brewster-angle polarimeter for measurements of the linear polarization of the HI Lyman series lines (i.e., Ly-alpha, -beta, and -gamma) and of the O VI 1032 Angstrom line. In this paper, the optical design of the SPCH polarimeter is described. A relevant element of this design is the external occulter (EXO) that is supported on a boom, which is extended 10 m beyond the instrument aperture, once the instrument is in station. The analysis of the stray-light reduction provided by this occulting system is described in this paper. The principal source of stray light is solar disk light that is diffracted from the edge of the EXO and scattered from the telescope mirror. The analysis shows that the stray-light is < 10(-2) the coronal signal. This level of stray-light rejection minimizes the polarized stray light that may be introduced by the EXO's straight edge. The most appropriate material for the polarizer has been found to be CaF2. The material selection criteria are described. Finally, the paper illustrates with an example that if the linear polarization can be measured better than 1%, then the instrumental sensitivity to magnetic fields may reach a few gauss (> 2 gauss), in coronal active regions. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Fineschi, S (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Woodgate, Bruce/D-2970-2012; Romoli, Marco/H-6859-2012 NR 19 TC 4 Z9 4 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3250-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3764 BP 147 EP 160 DI 10.1117/12.371079 PG 14 WC Engineering, Aerospace; Astronomy & Astrophysics; Optics SC Engineering; Astronomy & Astrophysics; Optics GA BP33T UT WOS:000084756600015 ER PT S AU Cosmo, ML Smith, PL Atkins, N Suleiman, RM Gardner, LD Kohl, JL AF Cosmo, ML Smith, PL Atkins, N Suleiman, RM Gardner, LD Kohl, JL BE Fineschi, S Woodgate, BE Kimble, RA TI Fiat field of UVCS detectors for early part of SOHO mission SO ULTRAVIOLET AND X-RAY DETECTION, SPECTROSCOPY, AND POLARIMETRY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultraviolet and X-Ray Detection, Spectroscopy, and Polarimetry III CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE UV spectroscopy; detectors; calibration; flat field AB The Ultraviolet Coronagraph Spectrometer (UVCS) on the Solar and Heliospheric Observatory (SOHO) comprises two telescopes and two spectrometer channels for spatially resolved ultraviolet spectral diagnostics of the solar corona The principal lines for which the two channels are optimized are the H I "Lyman-alpha" line at 121.5 nn and the O VI (O5+) doublet at 103.2 and 103.7 mn. An "in-flight" method, using observations of stars and scattered solar disk light, has been devised to determine the flat field function, i.e., the relative detection efficiency of the detector pixels. We present the details and results of this process. Local pixel-to-pixel efficiency variation is found to be, typically, about +/-9% to +/-17% (1 sigma) for the H I Lyman-alpha channel and +/-9% for the O VI channel. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cosmo, ML (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Woodgate, Bruce/D-2970-2012 NR 4 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 0-8194-3250-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3764 BP 161 EP 167 DI 10.1117/12.371094 PG 7 WC Engineering, Aerospace; Astronomy & Astrophysics; Optics SC Engineering; Astronomy & Astrophysics; Optics GA BP33T UT WOS:000084756600016 ER PT B AU Dupree, AK AF Dupree, AK BE Morse, JA Shull, JM Kinney, AL TI Cool stars: Imaging and spectroscopy SO ULTRAVIOLET-OPTICAL SPACE ASTRONOMY BEYOND HST SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Ultraviolet-Optical Space Astronomy Beyond HST CY AUG 05-07, 1998 CL BOULDER, CO SP Astron Soc Pacific ID HUBBLE-SPACE-TELESCOPE; CORONA; EUVE AB Fundamental problems concerning the physics of the stars can be addressed with ultraviolet imaging and spectroscopic observations. Current space experiments provide a small sample of what can be expected from the next generation of ultraviolet-sensitive instruments. Examples from HST, ORFEUS, and EUVE demonstrate imaging of stellar surfaces, detection of stellar rotation and winds, and new coronal structures. The ultraviolet spectral region is important for many aspects of cool star physics: energy balance; conditions in extreme environments involving magnetic fields; detection of winds and mass loss; the study of atmospheres of giant planets orbiting cool stars; and critical problems of stellar evolution. However, greater sensitivity than now exists is needed to acquire spectra under rapidly changing stellar conditions and to reach a coherent sample of stars, namely those in clusters. In the EUVE region, improvement of both sensitivity and spectral resolution are desirable. Imaging in the ultraviolet also promises a unique view of high temperature plasma on and surrounding cool stars. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Dupree, AK (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 23 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 1-886733-85-6 J9 ASTR SOC P PY 1999 VL 164 BP 102 EP 111 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN32E UT WOS:000081619700014 ER PT B AU Latham, DW AF Latham, DW BE Morse, JA Shull, JM Kinney, AL TI The search for extrasolar planets from space at optical and ultraviolet wavelengths SO ULTRAVIOLET-OPTICAL SPACE ASTRONOMY BEYOND HST SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Ultraviolet-Optical Space Astronomy Beyond HST CY AUG 05-07, 1998 CL BOULDER, CO SP Astron Soc Pacific AB I summarize the status of ground-based radial-velocity searches for extrasolar planets, and I speculate about the new results that we can expect from such searches over the next few years. Then I summarize the plans for space-based astrometric searches for extrasolar planets, and I compare the capabilities of the Hipparcos, DIVA, FAME, GAIA, and SIM missions for detecting low-mass companions in samples of solar-type stars. 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 11 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 1-886733-85-6 J9 ASTR SOC P PY 1999 VL 164 BP 134 EP 141 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN32E UT WOS:000081619700018 ER PT S AU Wilkes, BJ Hooper, EJ McLeod, KK Elvis, MS Impey, CD Lonsdale, CJ Malkan, MA McDowell, JC AF Wilkes, BJ Hooper, EJ McLeod, KK Elvis, MS Impey, CD Lonsdale, CJ Malkan, MA McDowell, JC BE Cox, P Kessler, MF TI The far-infrared continuum of quasars SO UNIVERSE AS SEEN BY ISO, VOLS I AND II SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT Conference on the Universe as Seen by ISO CY OCT 20-23, 1998 CL PARIS, FRANCE SP European Spacy Agcy, Univ Paris, Inst Astrophysique Spatiale, Ctr Nat Etude Spatiale, Alcatel, Arianespace, IPAC, Despa, Observatoire Meudon, REOSC, SAP CEA Saclay DE quasars ID ENERGY-DISTRIBUTIONS; MOLECULAR GAS; EMISSION; ISOPHOT; SPECTRA; OBJECTS; Z=4.69; DUST AB ISO provides a key new far-infrared window through which to observe the multi-wavelength spectral energy distributions (SEDs) of quasars and active galactic nuclei (AGN). It allows us, for the first time, to observe a substantial fraction of the quasar population in the far-IR, and to obtain simultaneous, multiwavelength observations from 5-200 mu m. With these data we can study the behavior of the LR continuum in comparison with expectations from competing thermal and non-thermal models. A key to determining which mechanism dominates, is the measurement of the peak wavelength of the emission and the shape of the far-IR-mm turnover. Turnovers which are steeper than v(2.5) indicate thermal dust emission in the far-IR. Preliminary results from our ISO data show broad, fairly smooth, IR continuum emission With far-IR turnovers generally too steep to be explained by nonthermal synchrotron emission. Assuming thermal emission throughout leads to a wide inferred temperature range similar to 50 - 1000 K. The hotter material, often called the AGN component, probably originates in dust close to and heated by the central source: e.g. the ubiquitous molecular torus. The cooler emission is too strong to be due purely to cool, host galaxy dust, and so indicates either the presence of a starburst in addition to the AGN or AGN-heated dust covering a wider range of temperatures than present in the standard, optically thick torus models. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Wilkes, BJ (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 20 TC 8 Z9 8 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-708-9 J9 ESA SP PUBL PY 1999 VL 427 BP 845 EP 848 PN 1&2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN74P UT WOS:000082780900174 ER PT S AU Hooper, E Wilkes, B McLeod, KK Elvis, MS Impey, C Lonsdale, C Malkan, M McDowell, J AF Hooper, E Wilkes, B McLeod, KK Elvis, MS Impey, C Lonsdale, C Malkan, M McDowell, J BE Cox, P Kessler, MF TI The US Key Project on AGN spectral energy distributions (characteristics of the ISO data) SO UNIVERSE AS SEEN BY ISO, VOLS I AND II SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT Conference on the Universe as Seen by ISO CY OCT 20-23, 1998 CL PARIS, FRANCE SP European Spacy Agcy, Univ Paris, Inst Astrophysique Spatiale, Ctr Nat Etude Spatiale, Alcatel, Arianespace, IPAC, Despa, Observatoire Meudon, REOSC, SAP CEA Saclay DE ISOPHOT; infrared astronomy; quasars; spectral energy distributions ID ISOPHOT AB The US ISO Key Project on quasar spectral energy distributions seeks to better understand the very broad-band emission features of quasars from radio to X-rays. A key element of this project is observations of 72 quasars with the ISOPHOT instrument at 8 bands, from 5 to 200 mm. The sample was chosen to span a wide range of redshifts and quasar types. This paper presents an overview of the analysis and reduction techniques, as well as general trends within the data set (comparisons with IRAS fluxes, uncertainties as a function of background sky brightness, and an analysis of vignetting corrections in chopped observing mode). A more detailed look at a few objects in the sample is presented in Wilkes et al. (these proceedings). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hooper, E (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 5 TC 4 Z9 4 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-708-9 J9 ESA SP PUBL PY 1999 VL 427 BP 893 EP 896 PN 1&2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN74P UT WOS:000082780900187 ER PT J AU Schreiber, EA AF Schreiber, EA TI Problems encountered when banding frigatebirds and boobies SO WATERBIRDS LA English DT Article DE bands; Brown Booby; Fregata minor; Great Frigatebird; Masked Booby; Red-footed Booby; Sula dactylatra; Sula leucogaster; Sula sula AB Two problems were encountered when banding frigatebirds (Fregata spp.) and boobies (Sula spp.). These are related to 1) the age at which chicks are banded and 2) size differences in adults. The problems, not addressed in the North American Bird Banding guidelines published jointly by the U. S. Fish and Wildlife Service and Canadian Wildlife Service (USFWS, 1991), include guano buildup inside the bands of downy frigatebird chicks and geographical anti sexual size differences in adult birds of both genera. Both problems can cause deformities in the foot and leg of banded birds. I discuss correct procedures for banding these species and urge the development of longer lasting, non-corrosive, and easy to apply bands for long-lived birds. C1 Smithsonian Inst, Bird Dept, Washington, DC 20560 USA. RP Schreiber, EA (reprint author), Smithsonian Inst, Bird Dept, NHB MRC 114, Washington, DC 20560 USA. NR 7 TC 1 Z9 1 U1 1 U2 2 PU WATERBIRD SOC PI WASHINGTON PA NATL MUSEUM NATURAL HISTORY SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0738-6028 J9 WATERBIRDS JI Waterbirds PY 1999 VL 22 IS 2 BP 310 EP 313 DI 10.2307/1522222 PG 4 WC Ornithology SC Zoology GA 292MP UT WOS:000085799000016 ER PT B AU Owsley, DW Jantz, RL AF Owsley, DW Jantz, RL BE Bonnichsen, R TI Databases for Paleo-American skeletal biology research SO WHO WERE THE FIRST AMERICANS? LA English DT Proceedings Paper CT 58th Annual Biology Colloquium CY 1999 CL Oregon State Univ, Corvallis, OR HO Oregon State Univ AB This overview features a Smithsonian-University of Tennessee initiative to systematically document human skeletons from North America including Paleo-American remains. The goal is to gain anatomical and biomedical information through comprehensive examination and the application of modern biological and anthropological techniques. The database includes information on provenience, bone and dental inventories, demographics, skeletal and dental pathology, cranial and postcranial measurements, photographs and radiographs, and taphonomic observations. Specific examples illustrate the utility of this program to studies of the First Americans. C1 Smithsonian Inst, Natl Museum Amer Hist, Dept Anthropol, Washington, DC 20560 USA. NR 30 TC 4 Z9 4 U1 0 U2 1 PU OREGON STATE UNIV PRESS PI CORVALLIS PA 101 WALDO HALL, PO BOX 689, CORVALLIS, OR 97330 USA BN 0-912933-20-8 PY 1999 BP 79 EP 96 PG 18 WC Anthropology; Archaeology SC Anthropology; Archaeology GA BY83K UT WOS:000189474200004 ER PT B AU Owsley, DW AF Owsley, DW BE Bonnichsen, R TI From Jamestown to Kennewick: An analogy based on early Americans SO WHO WERE THE FIRST AMERICANS? LA English DT Proceedings Paper CT 58th Annual Biology Colloquium CY 1999 CL Oregon State Univ, Corvallis, OR HO Oregon State Univ AB The reburial of Native American skeletal collections has reinforced the need to systematically document remains prior to deaccession. This report illustrates the importance of museum curation of discoveries so that scientists can reevaluate old ideas or address new research questions while benefiting from advances in theory, technology, and the establishment of comparative databases. This narrative reviews the collection history of a 17th-century skeleton found in 1940 on Jamestown Island. The remains were identified as Native American and have been analyzed from different perspectives following various research paradigms and interests. Recent reanalysis shows that more can be learned using current approaches and technology including determination of the cause of death and information about health, plus recognition of an individual's African ancestry. Interests may change, and theoretical paradigms may shift, but without benefit of the primary evidence, future generations will be limited to our conclusions, as well as our mistakes. Had the National Park Service not requested formal analysis utilizing current standards, this individual, and others in the collection that had not been identified as African, could have been mistakenly repatriated and erroneously reinterred as the remains of Native Americans. C1 Smithsonian Inst, Natl Museum Amer Hist, Dept Anthropol, Washington, DC 20560 USA. NR 20 TC 2 Z9 2 U1 0 U2 0 PU OREGON STATE UNIV PRESS PI CORVALLIS PA 101 WALDO HALL, PO BOX 689, CORVALLIS, OR 97330 USA BN 0-912933-20-8 PY 1999 BP 127 EP 140 PG 14 WC Anthropology; Archaeology SC Anthropology; Archaeology GA BY83K UT WOS:000189474200006 ER PT S AU Nichols, JS Linsky, JL AF Nichols, JS Linsky, JL BE VanderHucht, KA Koenigsberger, G Eenens, PRJ TI Wolf-Rayet star spectra from 1150 angstrom to 1200 angstrom SO WOLF-RAYET PHENOMENA IN MASSIVE STARS AND STARBURST GALAXIES SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 193rd Symposium of the International-Astronomical-Union CY NOV 03-07, 1998 CL PUERTO VALLARTA, MEXICO SP Int Astron Union C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. RP Nichols, JS (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 SN 0074-1809 BN 1-58381-004-8 J9 IAU SYMP PY 1999 IS 193 BP 80 EP 81 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU34M UT WOS:000175726300019 ER PT S AU Turner, JL Beck, SC Ho, PTP AF Turner, JL Beck, SC Ho, PTP BE VanderHucht, KA Koenigsberger, G Eenens, PRJ TI Gas and hidden star formation in NGC 5253 SO WOLF-RAYET PHENOMENA IN MASSIVE STARS AND STARBURST GALAXIES SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 193rd Symposium of the International-Astronomical-Union CY NOV 03-07, 1998 CL PUERTO VALLARTA, MEXICO SP Int Astron Union ID MAGELLANIC CLOUDS; GALAXY NGC-5253; CO AB We confirm the presence of compact H II regions in the center of the starburst in NGC 5253 through the detection of optically thick free-free emission. The number of O-type stars implied by the excitation of these nebulae is nearly two orders of magnitude larger than what is indicated by the radio continuum fluxes. The compact H II regions are located 70 pc to the north of the location of the Wolf-Rayet feature. Implied extinctions are extremely high. Not all WR galaxies can be identified as such due to extinction. C1 Univ Calif Los Angeles, Div Astron & Astrophys, Los Angeles, CA 90024 USA. Tel Aviv Univ, Dept Astron, Ramat Aviv, Israel. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Turner, JL (reprint author), Univ Calif Los Angeles, Div Astron & Astrophys, Los Angeles, CA 90024 USA. NR 9 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 0074-1809 BN 1-58381-004-8 J9 IAU SYMP PY 1999 IS 193 BP 758 EP 759 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU34M UT WOS:000175726300192 ER PT B AU Traub, WA AF Traub, WA BE Unwin, S Stachnik, R TI Scientific and technical progress at IOTA SO WORKING ON THE FRINGE: OPTICAL AND IR INTERFEROMETRY FROM GROUND AND SPACE SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Working on the Fringe - Optical and IR Interferometry from Ground and Space CY MAY 24-27, 1999 CL DANA POINT, CA ID INTERFEROMETER AB Works-in-progress and recently published results from the IOTA interferometer include these topics: (1) The shape and diameter of the dust envelope around the object CI Cam were measured at H and K bands; the obscured object had a bright x-ray outburst in April 1998, and may possibly be a neutron star or black hole. (2) The angular sizes of the circumstellar dust disks around a number of Herbig AeBe stars, including AB Aur, were measured at H and K. (3) The semi-regular variable star SW Vir was observed at K band (in FLUOR mode) and evidence found for asymmetry of the disk. (4) The Mira R Leo was observed in K (FLUOR mode) and a diameter variation found indicating fundamental mode oscillation. (5) The Cepheid Zeta Gem was measured in K (FLUOR mode) and a significant diameter variation was seen. (6) The binary system G1570 was measured at K (classical mode) and component masses determined to about 1% accuracy. Technical advances and current projects include these items. (7) Operation at L-band was demonstrated. (8) The NICMOS3 camera is being used regularly in both classical and FLUOR modes. (9) The third telescope project is underway: the planned upgrades include a 5-axis secondary support, trihedral delay line mirrors, and a comprehensive new control system; an adaptive optics system is being planned. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Traub, WA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 13 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 1-58381-020-X J9 ASTR SOC P PY 1999 VL 194 BP 57 EP 63 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BP85M UT WOS:000086435300009 ER PT S AU Ivan, A Bruni, R Byun, K Christensen, F Gorenstein, P Romaine, S AF Ivan, A Bruni, R Byun, K Christensen, F Gorenstein, P Romaine, S BE Khounsary, AM Freund, AK Ishikawa, T Srajer, G Lang, J TI Design and optimization of multilayer coatings for hard x-ray mirrors SO X-RAY OPTICS DESIGN, PERFORMANCE, AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Design, Performance, and Applications CY JUL 20-21, 1999 CL DENVER, CO SP SPIE DE x-ray optics; multilayer coatings; graded multilayers; sputtering deposition AB We present the results from a systematic study of several different material combinations for multilayer coatings on flat silicon and fused silica substrates. To obtain high reflectivity in a broad energy bandpass for hard X-rays (> 10 keV), a graded d-spacing multilayer structure must satisfy a set of conditions, e.g., low surface and interface roughness/diffuseness, good layer thickness uniformity, low residual stresses, etc. The coating process must be stable and acurately controlled over long deposition times, and allow good reproducibility from one run to another. The deposition method used was DC magnetron sputtering at low argon pressures (1.5 to 3.5 mT). The materials selected for the reflector/spacer pair were W/Si, W/C, Ni/C, and Pt/C. The initial work consisted in calibrating the deposition rate and optimizing the process parameters (argon backpressure, target to substrate distance, and cathode current). The main characterization methods used were: Atomic Force Microscopy in tapping mode, stylus profilometry, and specular X-ray reflectivity. In the next stage of the study, constant and graded d-spacing multilayers were deposited on Si and float glass substrates, with the design structure based on a computer modelling of the X-ray reflectivity dependence with grazing angle and energy. A specular reflectivity scan was performed for each sample at 8.05 keV land also at higher energies for some samples) and was fitted using the IMD software [1] Cross-sectional TEM was performed on a limited number of samples to offer additional information. The analyses completed for W/Si, W/C, Pt/C, and Ni/C show for the best samples good uniformity and high reflectivity at 8.05 keV. The work in progress for Cu/Si and Mo/Si will be presented at the conference and will conclude this study of candidate materials and optimized designs for hard X-ray multilayer optics. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Ivan, A (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NR 3 TC 3 Z9 3 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 0-8194-3259-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3773 BP 107 EP 112 DI 10.1117/12.370082 PG 6 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BP12K UT WOS:000084197600012 ER PT S AU Schnopper, HW Silver, E Ingram, R Christensen, FE Hussain, A Barbera, M Romaine, S Collura, A Kenter, A Bandler, S Murray, S AF Schnopper, HW Silver, E Ingram, R Christensen, FE Hussain, A Barbera, M Romaine, S Collura, A Kenter, A Bandler, S Murray, S BE Hoover, RB Walker, ABC TI X-ray optics made from thin plastic foils SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Mission II CY JUL 18-20, 1999 CL DENVER, CO SP SPIE DE X-ray optics; Wolter I; thin foil optics; approximate optics ID TELESCOPE AB New design concepts and materials can be used to produce very lightweight, thin foil approximations, to Welter I and other X-ray optics. Structures are designed around a central hub and spacers that connect one (or two) spoked wheels. Figure defining, thin pins span the distance between the wheels. Thin, metal coated or multilayered, plastic foils can be formed into cones, cylinders or spirals for X-ray telescopes or lenses. Imaging and spectroscopic data obtained with X-ray lenses are presented and they indicate that a 60 cm diameter, 4.65 m focal length X-ray telescope can have a half power diameter of <2 arcmin. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Schnopper, HW (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RI Bandler, Simon/A-6258-2010; OI Bandler, Simon/0000-0002-5112-8106; collura, alfonso/0000-0001-9534-1235; Barbera, Marco/0000-0002-3188-7420 NR 13 TC 16 Z9 16 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 0-8194-3252-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3766 BP 350 EP 361 DI 10.1117/12.363649 PG 12 WC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology SC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology GA BN95G UT WOS:000083637600030 ER PT J AU Carlstead, K Mellen, J Kleiman, DG AF Carlstead, K Mellen, J Kleiman, DG TI Black rhinoceros (Diceros bicornis) in US zoos: I. Individual behavior profiles and their relationship to breeding success SO ZOO BIOLOGY LA English DT Article DE novel object; observer ratings; animal personality; captive propagation; dominant behavior; fear ID SOCIAL-BEHAVIOR; PERSONALITY; TEMPERAMENT; WELFARE; MONKEYS AB This is the first part of a multi-zoo study to analyze the effects of captive environments on black rhinoceros (Diceros bicornis) behavior, breeding success, and well-being. We estimated the reliability and validity of a standardized method of cross-institutional assessment of the behavior of individual rhinoceros. In 1994 and 1995, we asked zookeepers at 19 toes to rate their black rhinoceros (a total of 60 animals) on 52 behavior elements using a questionnaire. At 14 toes, at least two keepers rated all the black rhinoceros at their zoo. We used average differences in their ratings of the 52 behavior elements to determine the most reliably rated behavior elements. Fourteen elements were retained for further analysis. Based on their inter-correlations, we grouped these 14 behaviors into six behavior traits: olfactory behaviors, chasing/stereotypy/mouthing, friendly to keeper fearful, patrolling and dominant (to conspecifics). A behavior profile of each animal consisted of scores on these six traits that were the sum of the primary keeper's ratings for each element in the group. To test the validity of these profiles, we compared scores on the six traits to the behavior of each rhinoceros during a standardized test of reactivity to a novel object and a novel conspecific scent. Tests were videotaped and analyzed by one researcher. Frequencies and durations of behaviors observed during the tests were correlated with scores on all six rated behavior traits. Scores on friendly to keeper, dominant, and olfactory behaviors described differences between black rhinoceros of captive/wild caught origin, age,and sex, respectively. Among successfully breeding males, scores on dominant and olfactory behaviors were negatively correlated with reproductive success, as was chasing/stereotypy/mouthing for females. To test the repeatability of these results, during 1996-1997, we used a modified questionnaire to re-survey 70 black rhinoceros at 24 toes. Results of the second survey were also similar to those of the first with respect to the behaviors that distinguish rhinoceros of different origin, age, sex, and reproductive success. We conclude that ratings by keepers of behavior and temperament attributes can be used as reliable and valid cross-institutional descriptions of individual differences between black rhinoceros. (C) 1999 Wiley-Liss, Inc. C1 Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. Disneys Anim Kingdom, Lake Buena Vista, FL USA. RP Carlstead, K (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. NR 31 TC 64 Z9 68 U1 3 U2 44 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 1999 VL 18 IS 1 BP 17 EP 34 DI 10.1002/(SICI)1098-2361(1999)18:1<17::AID-ZOO4>3.0.CO;2-K PG 18 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 173AM UT WOS:000078958800003 ER PT J AU Carlstead, K Fraser, J Bennett, C Kleiman, DG AF Carlstead, K Fraser, J Bennett, C Kleiman, DG TI Black rhinoceros (Diceros bicornis) in US zoos: II. Behavior, breeding success, and mortality in relation to housing facilities SO ZOO BIOLOGY LA English DT Article DE enclosure size; zoo visitors; dominant behavior; chlorine; olfactory behavior; stereotypy ID INDIVIDUAL-DIFFERENCES; ENVIRONMENT; MANAGEMENT; RESPONSES; VISITORS; PRIMATES; PIGS AB The captive population of black rhinoceros (Diceros bicornis) is not self-sustaining. The reasons for suboptimal reproduction and high mortality need to be investigated. This can only be achieved by cross-institutional analyses of environments, behavior, and performance. In this study, we collected data on 23 zoos with black rhinoceros to compare zoo environments with reproductive success, mortality, and behavior. Institutional variation was characterized by enclosure area, percentage of walls around enclosure perimeter, percentage of public access along enclosure perimeter, climate, noise level, number of years zoo has maintained black rhinoceros, frequency of chlorine use, and number of male and female black rhinoceros at a zoo simultaneously. Birth and death rates for each institution were calculated from studbook records. We found that the breeding success of a zoo since 1973 correlated positively with enclosure area, and zoos with two or more females had a lower reproductive rate than zoos with only one female. Females residing during their pre-reproductive years at a zoo with another reproductive female gave birth for the first time on average 3 years later than sole females. Mortality since 1973 correlated positively with percentage of public access. In Part I, we developed behavior profiles of 29.31 individual black rhinoceros from keeper ratings. Scores for males on the behavior trait Fear also correlated positively to percentage of public access, and we suggest that this aspect of black rhinoceros exhibits is a stressor for this species, especially the males. We found that different aspects of captive environments are associated with male and female black rhinoceros behavior. Male scores on the behavior trait dominant were higher in smaller enclosures, and female scores for a group of behaviors suggesting agitation (chasing/stereotypy/mouthing) were positively correlated with percentage of walls in their enclosure. These two behavior traits were found in Part I to be negatively correlated with the breeding success of an individual male or female. We re-surveyed the behavior and husbandry of 29 black rhinoceros pairs in zoos 2 years after the original data were collected. The re-survey confirmed that compatible black rhinoceros pairs are those with assertive females and submissive males, and that enclosure area and a low percentage of concrete walls around the enclosure are positive predictors of a pair's reproductive success. We conclude that temperament traits of individuals and characteristics of their captive environments both have an impact on a pair's breeding success. Our study demonstrates that cross-institutional comparisons of zoo facilities, when integrated with behavioral assessments of individual animals, are a valuable tool for investigating potential causes of poor reproduction and well-being in zoo animals. (C) 1999 Wiley-Liss, Inc. C1 Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. Metro Washington Pk Zoo, Portland, OR USA. Dallas Zoo, Dallas, TX USA. RP Carlstead, K (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. EM kcarlstead@nzp.si.edu NR 33 TC 56 Z9 60 U1 3 U2 46 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0733-3188 EI 1098-2361 J9 ZOO BIOL JI Zoo Biol. PY 1999 VL 18 IS 1 BP 35 EP 52 DI 10.1002/(SICI)1098-2361(1999)18:1<35::AID-ZOO5>3.0.CO;2-L PG 18 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 173AM UT WOS:000078958800004 ER PT J AU Brown, JL Hildebrandt, TB Theison, W Neiffer, DL AF Brown, JL Hildebrandt, TB Theison, W Neiffer, DL TI Endocrine and ultrasound evaluation of a non-cycling African elephant: Identification of an ovarian follicular cyst SO ZOO BIOLOGY LA English DT Article DE Loxodonta africana; progesterone; ultrasonography; ovary; follicle; human chorionic gonadotropin; gonadotropin-releasing hormone; luteinizing hormone; ovarian cyst ID DAIRY-COWS; LOXODONTA-AFRICANA; MAXIMUS; SERUM AB The reproductive rate of captive African elephants is :low because of logistical difficulties associated with transporting animals for breeding, the danger of maintaining bulls and medical or physiological problems. There also is growing evidence that a significant number of mature female elephants are not experiencing normal estrous cycles. The case described in this :report involves the diagnosis and attempted treatment of an ovarian follicular cyst in an African elephant at the Pittsburgh Zoo. On the basis of serum progesterone analysis, the female exhibited regular ovarian cycles from July 1993 through March 1994, but from November 1994 to the present has not shown any evidence of reproductive cyclicity. In April 1996, a large follicular structure was identified on the right ovary using transrectal ultrasound. In an attempt to luteinize the cyst, 500 mu g gonadotropin-releasing hormone (GnRH) was administered intravenously in October 1996, which stimulated a modest increase in serum luteinizing hormone (LH) (approximately twofold over baseline), but no resumption of ovarian activity. The elephant was treated again 5 months later with a higher dose of GnRH (5 mg, i.v.) with the same results. An ultrasound evaluation in July 1997 indicated the structure was still present. In October 1997, the female was given human chorionic gonadotropin (hCG; 10,000 TU, i.m.), which induced estrus and breeding, but no ovulation or luteinization of the cyst, and she remains acyclic. These results suggest that conventional methods developed in other species for treating ovarian follicular cysts may not necessarily be effective in the elephant. It is also important that reproductive age females be monitored via continuous progesterone analysis and occasional reproductive tract ultrasound evaluations to understand better the etiology of ovarian dysfunction so that effective treatments can be developed to induce consistent ovarian activity. Zoo BioI 18:223232, 1999. (C) 1999 Wiley-Liss, Inc. C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. Inst Zool Biol & Wildlife Res, Berlin, Germany. Pittsburgh Zoo, Pittsburgh, PA USA. Disneys Anim Kingdom, Lake Buena Vista, FL USA. RP Brown, JL (reprint author), Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. NR 14 TC 23 Z9 25 U1 0 U2 6 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 1999 VL 18 IS 3 BP 223 EP 232 DI 10.1002/(SICI)1098-2361(1999)18:3<223::AID-ZOO6>3.0.CO;2-F PG 10 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 242CF UT WOS:000082920100006 ER PT J AU Wielebnowski, NC AF Wielebnowski, NC TI Behavioral differences as predictors of breeding status in captive cheetahs SO ZOO BIOLOGY LA English DT Article DE Acinonyx jubatus; captive propagation; animal personality; individual behavioral variation ID YELLOW-BELLIED MARMOTS; INDIVIDUAL-DIFFERENCES; REPRODUCTIVE SUCCESS; ACINONYX-JUBATUS; OVARIAN-FUNCTION; SOCIAL-BEHAVIOR; SEX-DIFFERENCES; FECAL STEROIDS; DOMESTIC CATS; PERSONALITY AB Individual behavioral variation of 44 adult captive-born cheetahs, Acinoayx jubatus, was assessed using observer and keeper ratings on a variety of behavioral attributes. Inter-rater consensus was high for most questionnaire items, several of which were significantly correlated with direct behavioral measures recorded in a mirror-image experiment. Principal component analysis was applied to identify patterns of individual variation as measured by observer and keeper ratings. Three major components, labeled as tense-fearful, excitable-vocal, and aggressive, accounted for 69% of the observed variation. Females showed significantly higher scores on the component tense-fearful than males. Non-breeders of both sexes scored significantly higher on the component tense-fearful than breeders. Assessment of individual behavioral variation through questionnaire ratings may therefore provide a simple and non-invasive tool for predicting an individual's ability to adjust to the constraints of certain husbandry regimens and to reproduce in captivity. Simple measures of behavioral attributes may offer new insights for solving breeding problems and improving conservation management of endangered species in captivity. Zoo Biol 18.335-349, 1999. (C) 1999 Wiley-Liss, Inc. C1 Univ Calif Davis, Dept Wildlife Fisheries & Conservat Biol, Davis, CA 95616 USA. RP Wielebnowski, NC (reprint author), Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. NR 92 TC 67 Z9 69 U1 4 U2 64 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 1999 VL 18 IS 4 BP 335 EP 349 DI 10.1002/(SICI)1098-2361(1999)18:4<335::AID-ZOO8>3.0.CO;2-X PG 15 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 262HR UT WOS:000084061700008 ER PT J AU Roberts, TR AF Roberts, TR TI Systematic revision of the balitorid loach genus Sewellia of Vietnam and Laos, with diagnoses of four new species SO RAFFLES BULLETIN OF ZOOLOGY LA English DT Article DE Sewellia; Vietnam; Laos; leach; new species AB The highly specialized rheophilic leach genus Sewellia Hora, 1932 and its only previously known species, the Vietnamese S. lineolata (Valenciennes, 1849), are redescribed based on recently collected material. Four new species are described: S. pterolineata from Vietnam and S. speciosa from Laos in the nominal subgenus Sewellia, and S. diardi and S. elongata from Laos in the new subgenus Diardichthys. All species from Laos are from hill streams in the Se Kong watershed (Mekong basin). The species differ in size, scale counts, coloration, sexual dimorphism, and vertebral counts. Scanning electron micrographic observations are presented on tubercles and on unculiferous and non-unculiferous epidermal structures of the mouth and fins. C1 Smithsonian Trop Res Inst, Washington, DC USA. Natl Univ Singapore, Dept Biol Sci, Singapore 117548, Singapore. RP Roberts, TR (reprint author), Smithsonian Trop Res Inst, Washington, DC USA. NR 6 TC 9 Z9 10 U1 0 U2 3 PU NATL UNIV SINGAPORE, SCHOOL BIOLOGICAL SCIENCES PI SINGAPORE PA DEPT ZOOLOGY, KENT RIDGE, SINGAPORE 0511, SINGAPORE SN 0217-2445 J9 RAFFLES B ZOOL JI Raffles Bull. Zool. PD DEC 30 PY 1998 VL 46 IS 2 BP 271 EP 288 PG 18 WC Zoology SC Zoology GA 158PN UT WOS:000078124100002 ER PT J AU Roberts, TR AF Roberts, TR TI Pseudecheneis sympelvicus, a new species of rheophilic sisorid catfish from Laos (Mekong basin) SO RAFFLES BULLETIN OF ZOOLOGY LA English DT Article DE Pseudocheneis; catfish; Laos; new species AB Pseudecheneis sympelvicus, new species (Siluriformes: Sisoridae) is described from the Nam Theun watershed of the Mekong basin in Laos. It is the only known catfish with united pelvic fins. In the structure of the specialized thoracic adhesive disc and other important respects, it agrees very well with the type species and other described members of the genus Pseudecheneis. C1 Smithsonian Trop Res Inst, Washington, DC USA. RP Roberts, TR (reprint author), Smithsonian Trop Res Inst, Washington, DC USA. NR 7 TC 11 Z9 12 U1 0 U2 1 PU NATL UNIV SINGAPORE, SCHOOL BIOLOGICAL SCIENCES PI SINGAPORE PA DEPT ZOOLOGY, KENT RIDGE, SINGAPORE 0511, SINGAPORE SN 0217-2445 J9 RAFFLES B ZOOL JI Raffles Bull. Zool. PD DEC 30 PY 1998 VL 46 IS 2 BP 289 EP 292 PG 4 WC Zoology SC Zoology GA 158PN UT WOS:000078124100003 ER PT J AU Newman, LJ Cannon, LRG AF Newman, LJ Cannon, LRG TI Pseudoceros (Platyhelminthes : Polycladida) from the Indo-Pacific with twelve new species from Australia and Papua New Guinea SO RAFFLES BULLETIN OF ZOOLOGY LA English DT Article DE Pseudoceros; Platyhelminthes; Polycladida; taxonomy ID FLATWORM; PATTERN; COLOR AB New records of previously described species of Pseudoceros from eastern and western Australia, Indonesia, Philippines, Micronesia and Kenya are presented. In addition, twelve new species of Pseudoceros are described from subtropical and tropical waters of Australia and eastern Papua New Guinea. Species are diagnosed on the basis of their dorsal colour pattern, though details of the reproductive anatomy are also given. C1 Univ Queensland, Dept Zool, Brisbane, Qld 4072, Australia. Queensland Museum, Brisbane, Qld 4101, Australia. RP Newman, LJ (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. NR 39 TC 13 Z9 16 U1 0 U2 2 PU NATL UNIV SINGAPORE, SCHOOL BIOLOGICAL SCIENCES PI SINGAPORE PA DEPT ZOOLOGY, KENT RIDGE, SINGAPORE 0511, SINGAPORE SN 0217-2445 J9 RAFFLES B ZOOL JI Raffles Bull. Zool. PD DEC 30 PY 1998 VL 46 IS 2 BP 293 EP 323 PG 31 WC Zoology SC Zoology GA 158PN UT WOS:000078124100004 ER PT J AU Erdmann, MV Manning, RB AF Erdmann, MV Manning, RB TI Preliminary descriptions of nine new stomatopod crustaceans from coral reef habitats in Indonesia and Australia SO RAFFLES BULLETIN OF ZOOLOGY LA English DT Article DE Stomatopoda; taxonomy; new species; Indonesia; Australia AB Preliminary accounts are presented of nine new species of stomatopods representing three families. Gonodactylidae: three species of Gonodactylellus; one of Gonoclactylopsis, the third species of the genus; and one of Hoplosquilla, the second species of the genus. Protosquillidae: one species of Chorisquilla and two of Haptosquilla. Nannosquillidae: one of Nannosquilla, the first species of the genus to be recorded from outside the Americas. All of these species are very small, none exceeding 30 mm in total length as adults. C1 Univ Calif Berkeley, Dept Integrat Biol, Berkeley, CA 94720 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Erdmann, MV (reprint author), Univ Calif Berkeley, Dept Integrat Biol, Berkeley, CA 94720 USA. NR 4 TC 7 Z9 9 U1 1 U2 5 PU NATL UNIV SINGAPORE, SCHOOL BIOLOGICAL SCIENCES PI SINGAPORE PA DEPT ZOOLOGY, KENT RIDGE, SINGAPORE 0511, SINGAPORE SN 0217-2445 J9 RAFFLES B ZOOL JI Raffles Bull. Zool. PD DEC 30 PY 1998 VL 46 IS 2 BP 615 EP 626 PG 12 WC Zoology SC Zoology GA 158PN UT WOS:000078124100026 ER PT J AU Timmermans, E AF Timmermans, E TI Phase separation of Bose-Einstein condensates SO PHYSICAL REVIEW LETTERS LA English DT Article ID ATOMS; GAS AB We distinguish two types of spatial separation exhibited by atomic trap Bose-Einstein condensates: potential separation, in which case the condensates diffuse into each other as the trap is opened adiabatically, and phase separation, in which case the separation persists in the absence of external potentials. We discuss relevant features of the dynamics and statics of the phase separation of dilute condensates. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Timmermans, E (reprint author), Univ Calif Los Alamos Natl Lab, T-4,MS B-268, Los Alamos, NM 87545 USA. NR 16 TC 262 Z9 264 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 DEC 28 PY 1998 VL 81 IS 26 BP 5718 EP 5721 DI 10.1103/PhysRevLett.81.5718 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200004 ER PT J AU Medvedev, MV Diamond, PH Rosenbluth, MN Shevchenko, VI AF Medvedev, MV Diamond, PH Rosenbluth, MN Shevchenko, VI TI Asymptotic theory of nonlinear Landau damping and particle trapping in waves of finite amplitude SO PHYSICAL REVIEW LETTERS LA English DT Article ID ALFVEN WAVES; FLUID MODELS; BETA PLASMA; DISCONTINUITIES; PARALLEL AB A fully nonlinear, time-asymptotic theory of nonlinear Landau damping and resonant particle trapping in finite-amplitude waves is presented. The virial theorem and the conservation of the parallel adiabatic invariant are used to determine the time-asymptotic distribution function. The effect of trapped particles on the nonlinear wave dynamics is highly nontrivial and forces a significant departure from the conventional models of finite-amplitude waves. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RRC Kurchatov Inst, Inst Nucl Fus, Moscow 123182, Russia. Gen Atom Co, San Diego, CA 92121 USA. RP Medvedev, MV (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 19 TC 38 Z9 38 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 DEC 28 PY 1998 VL 81 IS 26 BP 5824 EP 5827 DI 10.1103/PhysRevLett.81.5824 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200029 ER PT J AU Petit, RE Harasewych, MG AF Petit, RE Harasewych, MG TI Cancellaria (Euclia) laurettae, a new species of cancellariidae (Mollusca : Neogastropoda) from Western Panama SO NAUTILUS LA English DT Article DE Cancellariidae; Panamic province; eastern Pacific; neogene; bathyal AB Cancellaria (Euclia) laurettae new species, is described from eleven specimens dredged in the Golfo de Chiriqui, Panama at depths of 270-360 meters. This species is assigned to the subgenus Euclia based on the morphology of its columellar plications, spiral sculpture, and overall shell shape. It is readily distinguished from the other Recent members of the subgenus by its lack of a distinct shoulder with spines or nodes and finer spiral sculpture. C1 Natl Museum Nat Hist, Dept Invertebrate Zool, Smithsonian Inst, Washington, DC 20560 USA. RP Petit, RE (reprint author), Natl Museum Nat Hist, Dept Invertebrate Zool, Smithsonian Inst, Washington, DC 20560 USA. NR 7 TC 4 Z9 4 U1 0 U2 0 PU BAILEY-MATTHEWS SHELL MUSEUM PI SANIBEL PA C/O DR JOSE H LEAL, ASSOCIATE/MANAGING EDITOR, 3075 SANIBEL-CAPTIVA RD, SANIBEL, FL 33957 USA SN 0028-1344 J9 NAUTILUS JI Nautilus PD DEC 23 PY 1998 VL 112 IS 4 BP 113 EP 116 PG 4 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 153RC UT WOS:000077845300004 ER PT J AU Hajdu, E Rutzler, K AF Hajdu, E Rutzler, K TI Sponges, genus Mycale (Poecilosclerida : Demospongiae : Porifera), from a Caribbean mangrove and comments on subgeneric classification SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article ID NEW-ZEALAND SPONGE; MARINE SPONGE; MYCALAMIDE-A AB Eight species of Mycale Gray (Mycalidae, Poecilosclerida, Demospongiae) are described from marine mangroves on the barrier reef of Belize, Central American Caribbean. Two are new: Mycale (Aegogropila?) carmigropila and M. (Ae.) citrina. Other species found are M. (Ae.) arndti, M. (Arenochalina) laxissima, M. (Carmia) magnirhaphidifera, M. (C.) microsigmatosa, M. (Mycale) laevis and M. (paresperella) sp. A key to the 17 recognized Caribbean species of Mycale is provided. Ectosomal skeletal patterns currently used as diagnostic characters for subgenera of Mycale may be inadequate for phylogenetic analysis, but reliable alternative congruent traits have not yet been identified to replace these. C1 Univ Amsterdam, Inst Syst & Populat Biol, NL-1090 GT Amsterdam, Netherlands. Smithsonian Inst, Natl Museum Amer Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Hajdu, E (reprint author), Fed Univ Rio De Janeiro, Museu Nacl, Dept Invertebrados, Quinta Boa Vista S-N, BR-20940040 Rio De Janeiro, Brazil. RI Hajdu, Eduardo/C-3863-2009 NR 90 TC 16 Z9 19 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 DEC 23 PY 1998 VL 111 IS 4 BP 737 EP 773 PG 37 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 154JX UT WOS:000077886700001 ER PT J AU Lu, H Fauchald, K AF Lu, H Fauchald, K TI Marphysa belli (Polychaeta : Eunicidae) and two related species, Marphysa oculata and M-totospinata, a new species, with notes on size-dependent features SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB Three morphologically related species, Marphysa belli, Marphysa oculata and Marphysa totospinata are described or re-described based on a morphometric study. The morphological differences among these species are discussed. The developmental patterns of antennae, branchiae and setae are emphasized. C1 Natl Museum Nat Hist, Dept Invertebrate Zool, Smithsonian Inst, Washington, DC 20560 USA. George Washington Univ, Dept Biol Sci, Washington, DC 20052 USA. RP Lu, H (reprint author), Natl Museum Nat Hist, Dept Invertebrate Zool, Smithsonian Inst, Washington, DC 20560 USA. NR 10 TC 8 Z9 8 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 DEC 23 PY 1998 VL 111 IS 4 BP 829 EP 842 PG 14 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 154JX UT WOS:000077886700008 ER PT J AU Heard, RW Manning, RB AF Heard, RW Manning, RB TI A new genus and species of ghost shrimp (Crustacea : Decapoda : Callianassidae) from the Atlantic Ocean SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB Necallianassa berylae, new genus and species, are named from material taken at several locations off the coasts of Georgia and South Carolina in depths ranging from 35 to 75 m. Two eastern Atlantic species, Callianassa acanthura Caroli, 1946, and C. truncata Giard & Bonnier, 1890, are transferred to Necallianassa. Members of this new genus can be distinguished from other members of the Callianassinae by the presence of a lateral spine on the uropodal endopod and one or two lateral spines on the telson. C1 Gulf Coast Res Lab, Invertebrate Zool Sect, Ocean Springs, MS 39564 USA. Natl Museum Nat Hist, Dept Invertebrate Zool, Smithsonian Inst, Washington, DC 20560 USA. RP Heard, RW (reprint author), Gulf Coast Res Lab, Invertebrate Zool Sect, Ocean Springs, MS 39564 USA. NR 3 TC 12 Z9 13 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 DEC 23 PY 1998 VL 111 IS 4 BP 883 EP 888 PG 6 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 154JX UT WOS:000077886700013 ER PT J AU Manning, RB Tamaki, A AF Manning, RB Tamaki, A TI A new genus of ghost shrimp from Japan (Crustacea : Decapoda : Callianassidae) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article ID THALASSINIDEA AB A new genus, Nihonotrypcaea, is recognized for three species from Japan formerly assigned to Callianassa sensu late: N. japonica (Ortmann, 1891), the type species; N. harmandi (Bouvier, 1901); and N. petalura (Stimpson, 1860). C1 Smithsonian Inst, Museum Natl Hist Nat, Dept Invertebrate Zool, Washington, DC 20560 USA. Nagasaki Univ, Fac Fisheries, Nagasaki 8528521, Japan. RP Manning, RB (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 13 TC 34 Z9 37 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 DEC 23 PY 1998 VL 111 IS 4 BP 889 EP 892 PG 4 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 154JX UT WOS:000077886700014 ER PT J AU Campos, MR Lemaitre, R AF Campos, MR Lemaitre, R TI A new freshwater crab of the genus Neostrengeria Pretzmann, 1965, from Colombia (Crustacea : Decapoda : Brachyura : Pseudothelphusidae), with a key to the species of the genus SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB A new species of freshwater crab of the pseudothelphusid genus Neostrengeria Pretzmann, 1965, N. perijaensis, is described and illustrated. This discovery means the genus now contains a total of 17 species and 2 subspecies, all endemic to the Eastern Andes of Colombia. The general characteristics of the genus are given, and a key for the identification of the species based primarily on the morphology of the male first gonopod, is presented. C1 Univ Nacl Colombia, Inst Ciencias Nat, Santa Fe De Bogota 114 2, Colombia. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Campos, MR (reprint author), Univ Nacl Colombia, Inst Ciencias Nat, Apartado Aereo 53416, Santa Fe De Bogota 114 2, Colombia. NR 15 TC 6 Z9 7 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 DEC 23 PY 1998 VL 111 IS 4 BP 899 EP 907 PG 9 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 154JX UT WOS:000077886700016 ER PT J AU Williams, AB Hernandez-Aguilera, JL AF Williams, AB Hernandez-Aguilera, JL TI A new species of mud shrimp, Upogebia toralae, from Veracruz, Mexico (Decapoda : Thalassinidea : Upogebiidae) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB Upogebia toralae, a new species of mud shrimp from Veracruz, Mexico is described and illustrated. The unique female holotype was collected intertidally in the Port of Veracruz which is strongly impacted by human activity. The species shares with many members of the genus from the western hemisphere a strongly developed proximal mesioventral spine on the merus of the second pereopod. The species stands alone, however, with respect to other characters. The triangular rostrum has no ventral spines, the anterior gastric region bears many anteriorly setose spines that art more or less transversely elongate and scalelike, and the palms of the chelae have a dorsal ridge that bears three erect and somewhat hooked spines on its proximal end. C1 Smithsonian Inst, Museum Natl Hist Nat, Natl Marine Fisheries Serv Systemat Lab, Washington, DC 20560 USA. Univ Nacl Autonoma Mexico, Fac Ciencias, Mexico City 04510, DF, Mexico. Univ Nacl Autonoma Mexico, Inst Ciencias Mar & Limnol, Mexico City 04510, DF, Mexico. RP Williams, AB (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Natl Marine Fisheries Serv Systemat Lab, Washington, DC 20560 USA. NR 4 TC 0 Z9 0 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 DEC 23 PY 1998 VL 111 IS 4 BP 908 EP 911 PG 4 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 154JX UT WOS:000077886700017 ER PT J AU Campos, E Manning, RB AF Campos, E Manning, RB TI Pinnotheres malaguena Garth, 1948, a new member of the genus Fabia Dana, 1851 (Crustacea : Brachyura : Pinnotheridae) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB The original description and figures of the male holotype of the pinnotherid crab Pinnotheres malaguena Garth are emended. The morphology of this species excludes it from Pinnotheres Bose, 1802 but supports its transfer to the genus Fabia Dana, 1851. Fabia malaguena can be distinguished from other members of Fabia by its unique gonopod shape and its abdomen, which has somites 5 to the telson fused. C1 Univ Autonoma Baja California, Fac Ciencias, Ensenada 22800, Baja California, Mexico. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Campos, E (reprint author), Univ Autonoma Baja California, Fac Ciencias, Apartado Postal 2300, Ensenada 22800, Baja California, Mexico. NR 10 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 DEC 23 PY 1998 VL 111 IS 4 BP 912 EP 915 PG 4 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 154JX UT WOS:000077886700018 ER PT J AU Vari, RP Ferraris, CJ AF Vari, RP Ferraris, CJ TI The neotropical catfish genus Epapterus Cope (Siluriformes : Auchenipteridae): a reappraisal SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB The Neotropical auchenipterid catfish genus Epapterus Cope is reviewed. Epapterus was found to share synapomorphies with Auchenipterus Valenciennes and Pseudepapterus Steindachner and within that clade it is the sister-group to Pseudepapterus. Epapterus lacks an adipose dorsal fin, a derived reductive feature unique to the genus within the clade consisting of Epapterus, Auchenipterus, and Pseudepapterus and which is hypothesized to be a synapomorphy for the genus. The extension of the interradial membrane to join the contralateral pelvic fins is identified as an additional possible synapomorphy for Epapterus. Contrary to recent practice, Epapterus is considered to consist of only two species, E. dispilurus Cope (1878) and E, blohmi Vari et al. (1984). Examination of Epapterus samples from a number of localities in the Rio Amazonas and Rio Paraguay basins failed to reveal differences between the populations of the genus in those drainage systems. As a consequence Epapterus chaquensis Risso & Risso (1962), described from the Rio Paraguay system, is placed as a synonym of E. dispilurus originally described from the western portion of the Amazon basin. Euanemus longipinnis Steindachner (1881) is retained as a synonym of Epapterus dispilurus as proposed by Steindachner (1882) and Eigenmann & Eigenmann (1888). Epapterus dispilurus is found to have a broad distribution in the central and western portions of the Rio Amazonas system and the Rio Paraguay basin. The distribution of E. blohmi is extended from the state of Guarico, Venezuela to include other portions of the Rio Orinoco basin and the Rio Tuy of the Caribbean coast of Venezuela. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. Calif Acad Sci, Dept Ichthyol, San Francisco, CA 94118 USA. RP Vari, RP (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. NR 35 TC 4 Z9 5 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 DEC 23 PY 1998 VL 111 IS 4 BP 992 EP 1007 PG 16 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 154JX UT WOS:000077886700026 ER PT J AU Emlen, ST Wrege, PH Webster, MS AF Emlen, ST Wrege, PH Webster, MS TI Cuckoldry as a cost of polyandry in the sex-role-reversed wattled jacana, Jacana jacana SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE extra-pair fertilizations; jacana; polyandry; sex-role reversal; sperm competition; sperm storage ID DUNNOCKS PRUNELLA-MODULARIS; PARENTAL CARE; HUMAN DNA; PATERNITY; BEHAVIOR; BIRD; FERTILIZATIONS; SPINOSA; SUCCESS; SPERM AB In this paper we provide the first molecular genetic data on extra-pair paternity in a simultaneously polyandrous, sex-role-reversed avian species, the wattled jacana (Jacana jacana). Female jacanas often copulated with multiple mates, provided that the mates were not actively incubating eggs or tending young chicks. Both the presence of multiple 'available' mates, and the copulation behaviour of the female near the time of nest initiation, significantly predicted the probability of extra-pair fertilizations. A male's risk of being cuckolded was 0% in monandrous pairings, rose to 41% of broods (17% of chicks) in polyandrous associations where an additional mate was 'available', and increased to 74% of broods (29% of chicks) where the female was observed to copulate with multiple mates. Unlike findings from several sequentially polyandrous bird species, few if any fertilizations resulted from sperm stored from a previous nesting. We conclude that lost paternity can constitute a very real cost of polyandry for male wattled jacanas. The source of this cost is sexually active males simultaneously paired to the same female. C1 Cornell Univ, Neurobiol & Behav Sect, Ithaca, NY 14853 USA. Smithsonian Trop Res Inst, Balboa, Panama. SUNY Buffalo, Dept Sci Biol, Buffalo, NY 14260 USA. RP Emlen, ST (reprint author), Cornell Univ, Neurobiol & Behav Sect, Seeley G Mudd Hall, Ithaca, NY 14853 USA. EM stel@cornell.edu NR 31 TC 37 Z9 38 U1 3 U2 28 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 EI 1471-2954 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD DEC 22 PY 1998 VL 265 IS 1413 BP 2359 EP 2364 PG 6 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 154VX UT WOS:000077911400003 ER PT J AU Ebeling, H Edge, AC Bohringer, H Allen, SW Crawford, CS Fabian, AC Voges, W Huchra, JP AF Ebeling, H Edge, AC Bohringer, H Allen, SW Crawford, CS Fabian, AC Voges, W Huchra, JP TI The ROSAT Brightest Cluster Sample - I. The compilation of the sample and the cluster log N log S distribution SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Review DE catalogues; surveys; galaxies : clusters : general; cosmology : observations; large-scale structure of Universe; X-rays : galaxies ID ALL-SKY SURVEY; MEDIUM SENSITIVITY SURVEY; LARGE-SCALE DISTRIBUTION; SOUTHERN GALAXY CATALOG; X-RAY-CLUSTERS; ABELL CLUSTERS; REDSHIFT SURVEY; OPTICAL SPECTROSCOPY; VIRGO CLUSTER; VELOCITY DISPERSIONS AB We present a 90 per cent flux-complete sample of the 201 X-ray-brightest clusters of galaxies in the northern hemisphere (delta greater than or equal to 0 degrees), at high Galactic latitudes (\b\ greater than or equal to 20 degrees), with measured redshifts z less than or equal to 0.3 and fluxes higher than 4.4 x 10-(12) erg cm(-2) s(-1) in the 0.1-2.4 keV band. The sample, called the ROSAT Brightest Cluster Sample (BCS), is selected from ROSAT All-Sky Survey data and is the largest X-ray-selected cluster sample compiled to date. In addition to Abell clusters, which form the bulk of the sample, the BCS also contains the X-ray-brightest Zwicky clusters and other clusters selected from their X-ray properties alone. Effort has been made to ensure the highest possible completeness of the sample and the smallest possible contamination by non-cluster X-ray sources. X-ray fluxes are computed using an algorithm tailored for the detection and characterization of X-ray emission from galaxy clusters. These fluxes are accurate to better than 15 per cent (mean 1 sigma error). We find the cumulative log N-log S distribution of clusters to follow a power law kappa S-alpha with alpha = 1.31(-0.03)(+0.06) (errors are the 10th and 90th percentiles) down to fluxes of 2 x 10(-12) erg cm-2 s(-1), i.e. considerably below the BCS flux limit. Although our best-fitting slope disagrees formally with the canonical value of - 1.5 for a Euclidean distribution, the BCS log N-log S distribution is consistent with a non-evolving cluster population if cosmological effects are taken into account. Our sample will allow us to examine large-scale structure in the northern hemisphere, determine the spatial cluster-cluster correlation function, investigate correlations between the X-ray and optical properties of the clusters, establish the X-ray luminosity function for galaxy clusters, and discuss the implications of the results for cluster evolution. C1 Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ebeling, H (reprint author), Max Planck Inst Extraterr Phys, Giessenbachstr, D-85740 Garching, Germany. NR 103 TC 461 Z9 463 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 DEC 21 PY 1998 VL 301 IS 4 BP 881 EP 914 DI 10.1046/j.1365-8711.1998.01949.x PG 34 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 154DA UT WOS:000077872300001 ER PT J AU Pen, UL Loeb, A Turok, N AF Pen, UL Loeb, A Turok, N TI Gamma-ray bursts from baryon decay in neutron stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : theory; gamma rays : bursts; stars : neutron ID FIREBALLS; NUCLEOSYNTHESIS; SYMMETRY; MODELS AB The standard unbroken electroweak theory is known to erase the baryon number. The baryon number symmetry can be restored in the core of a neutron star if its density diverges via gravitational instability due to a binary merger event. We argue that for certain double Higgs models with discrete symmetries this process may result in an expanding self-sustained burning front that would convert the entire neutron matter into radiation. This process would release similar to 10(54) ergs in electromagnetic radiation over similar to 10(-4) s with negligible baryonic contamination. The resulting fireball would have all of the properties necessary to produce a gamma-ray burst as a result of its interaction with ambient interstellar gas. The subsequent Higgs decay would produce a millisecond burst of similar to 10(52) ergs in similar to 100 GeV neutrinos, which might be observable. The above mechanism may also cause electroweak baryogenesis in the early universe, which gives rise to the observed matter-antimatter asymmetry today. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Cambridge, Dept Appl Math & Theoret Phys, Cambridge CB3 9EW, England. RP Pen, UL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 39 TC 4 Z9 4 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1998 VL 509 IS 2 BP 537 EP 543 DI 10.1086/306511 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DH UT WOS:000079250700005 ER PT J AU Impey, CD Falco, EE Kochanek, CS Lehar, J McLeod, BA Rix, HW Peng, CY Keeton, CR AF Impey, CD Falco, EE Kochanek, CS Lehar, J McLeod, BA Rix, HW Peng, CY Keeton, CR TI An infrared Einstein ring in the gravitational lens PG 1115+080 SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; gravitational lensing; quasars : individual (PG 1115+080) ID HUBBLE-SPACE-TELESCOPE; LARGE-SCALE STRUCTURE; TIME-DELAY; GALAXIES; PG-1115+080; CONSTANT; Q0957+561; GEOMETRY; MODEL; LIGHT AB Hubble Space Telescope observations of the gravitational lens PG 1115+080 in the infrared show the known z(l) = 0.310 lens galaxy and reveal the z(s) = 1.722 quasar host galaxy. The main lens galaxy G is a nearly circular (ellipticity epsilon < 0.07) elliptical galaxy with a de Vaucouleurs profile and an effective radius of R-e = 0." 59 + 0." 06 (1.7 +/- 0.2 h(-1) kpc for Omega(0) = 1 and h = H-0/100 km s(-1) Mpc(-1)). G is part of a group of galaxies that is a required component of all successful lens models. The new quasar and lens positions (3 mas uncertainty) yield constraints for these models that are statistically degenerate, but several conclusions are firmly established. (1) The principal lens galaxy is an elliptical galaxy with normal structural properties, lying close to the fundamental plane for its redshift. (2) The potential of the main lens galaxy is nearly round, even when not constrained by the small ellipticity of the light of this galaxy. (3) All models involving two mass distributions place the group component near the luminosity-weighted centroid of the brightest nearby group members. (4) All models predict a time delay ratio r(ABC) similar or equal to 1.3. (5) Our lens models predict H-0 = 44 +/- 4 km s(-1) Mpc(-1) if the lens galaxy contains dark matter and has a hat rotation curve and H-0 = 65 +/- 5 km s(-1) Mpc(-1) if it has a constant mass-to-light ratio. (6) Any dark halo of the main lens galaxy must be truncated near 1." 5 (4 h(-1) kpc) before the inferred H-0 rises above similar to 60 km s(-1) Mpc(-1). (7) The quasar host galaxy is lensed into an Einstein ring connecting the four quasar images, whose shape is reproduced by the models. Improved near-infrared camera multiobject spectrograph (NICMOS) imaging of the ring could be used to break the degeneracy of the lens models. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Impey, CD (reprint author), Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. EM cimpey@as.arizona.edu; falco@cfa.harvard.edu; ckochanek@cfa.harvard.edu; jlehar@cfa.harvard.edu; bmcleod@cfa.harvard.edu; rix@as.arizona.edu; cyp@as.arizona.edu; ckeeton@cfa.harvard.edu NR 57 TC 105 Z9 105 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 DEC 20 PY 1998 VL 509 IS 2 BP 551 EP 560 DI 10.1086/306521 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DH UT WOS:000079250700007 ER PT J AU Keeton, CR Kochanek, CS Falco, EE AF Keeton, CR Kochanek, CS Falco, EE TI The optical properties of gravitational lens galaxies as a probe of galaxy structure and evolution SO ASTROPHYSICAL JOURNAL LA English DT Review DE galaxies : evolution; galaxies : photometry; galaxies : structure; gravitational lensing ID HUBBLE-SPACE-TELESCOPE; HIGH-REDSHIFT GALAXIES; X-RAY CONSTRAINTS; TO-LIGHT RATIO; LUMINOSITY FUNCTION; EINSTEIN RING; ELLIPTIC GALAXIES; DARK-MATTER; COSMOLOGICAL CONSTANT; STELLAR POPULATIONS AB We combine photometry and lens modeling to study the properties of 17 gravitational lens galaxies between z = 0.1 and similar to 1. Most of the lens galaxies are passively evolving early-type galaxies, with a few spirals. The colors, scale lengths, and ellipticities of lens galaxies are similar to those of the general population of early-type galaxies, although there may be a deficit of apparently round lens galaxies produced by the inclination dependence of lensing cross sections. The projected mass distributions are aligned with the projected light distributions to less than or similar to 10 degrees, except in the presence of a strong external tidal perturbation, suggesting that dark matter halos are significantly modified by interactions with the baryonic component and are not far out of alignment with the stars. Lens galaxies obey image separation/lens luminosity correlations analogous to the Faber-Jackson and Tully-Fisher relations, which are consistent with standard dark matter lens models. The lens galaxy mass-to-light ratios decrease with redshift as d(log M/L-B)/dz = -0.3 +/- 0.1 (-0.5 +/- 0.1) for Omega(0) = 1 (0.1), thus providing direct evidence of passive evolution for a sample of early-type galaxies in low-density environments. The evolution-corrected mass-to-light ratios are generally larger than predicted by constant M/L dynamical models, although there is significant scatter; with improved photometry, lens galaxy mass-to-light ratios would better distinguish between constant M/L and dark matter models. These conclusions are limited primarily by the quality of lens galaxy photometry. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Keeton, CR (reprint author), Harvard Smithsonian Ctr Astrophys, MS-51,60 Garden St, Cambridge, MA 02138 USA. NR 140 TC 159 Z9 159 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 DEC 20 PY 1998 VL 509 IS 2 BP 561 EP 578 DI 10.1086/306502 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DH UT WOS:000079250700008 ER PT J AU Garay, G Kohnenkamp, I Bourke, TL Rodriguez, LF Lehtinen, KK AF Garay, G Kohnenkamp, I Bourke, TL Rodriguez, LF Lehtinen, KK TI Molecular abundance enhancements in the highly collimated bipolar outflow BHR 71 SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : abundances; ISM : individual (BHR 71); ISM : jets and outflows; ISM : molecules ID YOUNG STELLAR OBJECTS; LINE EMISSION MODELS; HERBIG-HARO OBJECTS; SMALL DARK CLOUDS; INTERSTELLAR CLOUDS; STAR-FORMATION; SIO EMISSION; L1157 OUTFLOW; BOW SHOCKS; CHEMISTRY AB We report observations of the J = 3 --> 2 and J = 2 --> 1 transitions of SiO and CS, the J(k) = 3(k) --> 2(k) and J(k) = 2(k) --> 1(k) transitions of CH(3)OH, and the J = 1 --> 0 transition of HCO(+), made with Swedish-ESO Submillimetre Telescope (SEST), toward the highly collimated bipolar outflow BHR 71. Broad wing emission was detected toward the outflow lobes in all the observed molecular lines. The shapes of the profiles are strikingly different from molecule to molecule. For CS and HCO(+) the emission from the outflowing gas appears as a weak broad feature superposed upon a strong narrow emission from the quiescent ambient gas. For CH,OH the intensity of the broad emission feature is considerably stronger than that of the narrow component, whereas for SiO the broad feature completely dominates the emission spectra. The spatial distribution of the integrated wing emission is considerably extended and broadly similar in all the observed molecular transitions, showing well-separated blueshifted and redshifted lobes with FWHM angular sizes of 2'.4 x 1'.3 and 2'.4 x 1'.4, respectively. We find that the abundance of methanol and silicon monoxide in the outflow lobes is enhanced with respect to that of the ambient cloud by factors of up to similar to 40 and 350, respectively. The large enhancements of methanal and silicon monoxide in the outflow lobes are most likely due to the release from grains of ice mantles and Si-bearing species via shocks produced by the interaction between the outflow and dense ambient gas. On the other hand, we find that the abundance of HCO(+) in the outflowing gas is smaller than that in the ambient gas by about a factor of 20, a decrease consistent with theoretical predictions of shock models. C1 Univ Chile, Dept Astron, Santiago, Chile. Univ New S Wales, Australian Def Force Acad, Univ Coll, Sch Phys, Canberra, ACT 2600, Australia. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico. Univ Helsinki, Helsinki Univ Observ, SF-00014 Helsinki, Finland. RP Garay, G (reprint author), Univ Chile, Dept Astron, Casilla 36-D, Santiago, Chile. EM guido@das.uchile.cl; tlb@aaoepp.aao.gov.au; kklehtin@cc.helsinki.fi RI Garay, Guido/H-8840-2013 OI Garay, Guido/0000-0003-1649-7958 NR 70 TC 49 Z9 49 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1998 VL 509 IS 2 BP 768 EP 784 DI 10.1086/306534 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DH UT WOS:000079250700026 ER PT J AU Calvet, N Gullbring, E AF Calvet, N Gullbring, E TI The structure and emission of the accretion shock in T Tauri stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; circumstellar matter; shock waves; stars : pre-main-sequence ID BALMER LINE-PROFILES; YOUNG STARS; DISK ACCRETION; VARIABILITY; IRRADIATION; EVOLUTION; ENVELOPES; OBJECTS; FLOWS; HOT AB We have examined one of the key predictions of the magnetospheric infall model for classical T Tauri stars (CTTS), namely, the formation of a shock on the stellar surface. We find that accretion column emission can successfully reproduce the main observational properties of the excess continuum that veils the absorption features in CTTS. This success adds further support to the magnetospheric infall model for disk accretion. We have calculated the structure and the spectral energy distribution of the emergent continuum emission from a shock at the base of the magnetospheric accretion column. We find that the spectral shape of the excess can be understood as optically thick emission from the heated photosphere below the shock, appearing mostly on the Paschen and Brackett continua, and optically thin emission from the preshock and attenuated postshock regions, dominating at wavelengths shorter than the Balmer threshold. The accretion luminosity and rate depend on two parameters: the energy flux of the accretion flow, F, and the surface coverage of the column, f with typical values log F similar to 10.5-11.5, of the order or up to a factor of 10 higher than the intrinsic stellar flux, and f similar to 0.1%-1% of the surface area. The so-called continuum stars have accretion columns with similar energy fluxes than the less veiled, typical CTTS but with much larger surface emitting areas of greater than or equal to 10%. At near-infrared wavelengths, the predicted veiling from the accretion column for typical CTTS parameters is nearly constant and less than or equal to 0.1. Only for the "continuum stars" are significant amounts of near-infrared veiling from the accretion column expected. For accretion columns with low values of F, the Paschen continuum emission has spectral features, rendering the usual deveiling procedures uncertain. Magnetospheric flow Balmer emission may also contribute to the excess for stars with low-F columns. Finally, accretion column emission can successfully reproduce the observed correlation between the excess luminosity at the U band and the accretion luminosity. This correlation does not depend on the characteristics (mass, spectral type) of the underlying star, at least in the range M3-K5. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Ctr Invest Astron, Merida, Venezuela. RP Calvet, N (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM ncalvet@cfa.harvard.edu; egullbring@cfa.harvard.edu NR 49 TC 374 Z9 375 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1998 VL 509 IS 2 BP 802 EP 818 DI 10.1086/306527 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DH UT WOS:000079250700029 ER PT J AU Gottlieb, CA McCarthy, MC Gordon, VD Chakan, JM Apponi, AJ Thaddeus, P AF Gottlieb, CA McCarthy, MC Gordon, VD Chakan, JM Apponi, AJ Thaddeus, P TI Laboratory detection of two new C5H2 isomers SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : molecules; line : identification; molecular data; molecular processes; radio lines : ISM ID TMC-1; H2C6 AB Two new isomers of the C5H2 molecule have been detected in the laboratory, and their microwave spectra have been characterized to high accuracy. Both are good candidates for radio astronomical detection. Like the two isomers previously detected in the laboratory, both are closed-shell carbenes, and both are extremely polar and fairly stable. The first, calculated to lie 0.73 eV above isomer 1, the C5H2 ring-chain ground state, has a bent carbon chain backbone with single, double, and triple bonds; the second, calculated to lie only 0.19 eV higher in energy, is a new type of ring chain formed by adding a pair of doubly bonded carbon atoms to the top of the C3H2 ring, which is one of the most abundant interstellar molecules. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gottlieb, CA (reprint author), Harvard Univ, Div Engn & Appl Sci, 29 Oxford St, Cambridge, MA 02138 USA. NR 11 TC 23 Z9 23 U1 0 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 DEC 20 PY 1998 VL 509 IS 2 BP L141 EP L144 DI 10.1086/311777 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DJ UT WOS:000079250800020 ER PT J AU Martin, EL Basri, G Brandner, W Bouvier, J Osorio, MRZ Rebolo, R Stauffer, J Allard, F Baraffe, I Hodgkin, ST AF Martin, EL Basri, G Brandner, W Bouvier, J Osorio, MRZ Rebolo, R Stauffer, J Allard, F Baraffe, I Hodgkin, ST TI Discovery of a very low mass binary with the Hubble Space Telescope near-infrared camera and multiobject spectrometer SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : general; open clusters and associations : individual (Pleiades); stars : evolution; stars : formation; stars : low-mass, brown dwarfs ID BROWN DWARFS; PLEIADES CLUSTER; CANDIDATES; SEQUENCE; LITHIUM; STARS AB Hubble Space Telescope Near-Infrared Camera and Multiobject Spectrometer (NICMOS) observations of six brown dwarf candidates in the Pleiades open cluster are presented. One of them, namely CFHT-Pl-18, is clearly resolved as a binary with an angular separation of 0".33. The very low density of contaminating background stars in our images and the photometry of the components support that this system is a physical binary rather than a chance projection. All of the available photometric and spectroscopic data indicate that the CFHT-Pl-18 system is likely a member of the Pleiades cluster, but a final confirmation will have to wait until lithium can be detected. Assuming cluster membership, we compare our NICMOS photometry with evolutionary models and find that the inclusion of the effects of dust grains is necessary for fitting the data. We estimate that the masses of the components are about 0.045 and 0.035 M.. The binary system has a projected separation of 42 AU (for a distance of 125 pc) that is common among stellar binaries. C1 Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Observ Grenoble, F-38041 Grenoble, France. Inst Astrofis Canarias, E-38200 La Laguna, Spain. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Ecole Normale Super Lyon, Ctr Rech Astron Lyon, F-69364 Lyon, France. Univ Leicester, Dept Phys & Astron, Astron Grp, Leicester LE1 7RH, Leics, England. RP Martin, EL (reprint author), Univ Calif Berkeley, Dept Astron, 601 Campbell Hall, Berkeley, CA 94720 USA. RI Zapatero Osorio, Maria Rosa/C-2744-2017 OI Zapatero Osorio, Maria Rosa/0000-0001-5664-2852 NR 21 TC 24 Z9 24 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1998 VL 509 IS 2 BP L113 EP L116 DI 10.1086/311775 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DJ UT WOS:000079250800013 ER PT J AU Michael, E McCray, R Pun, CSJ Borkowski, K Garnavich, P Challis, P Kirshner, RP Chevalier, R Filippenko, AV Fransson, C Panagia, N Phillips, M Schmidt, B Suntzeff, N Wheeler, JC AF Michael, E McCray, R Pun, CSJ Borkowski, K Garnavich, P Challis, P Kirshner, RP Chevalier, R Filippenko, AV Fransson, C Panagia, N Phillips, M Schmidt, B Suntzeff, N Wheeler, JC TI New Hubble Space Telescope observations of high-velocity Ly alpha and H alpha in SNR 1987A SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; shocks; supernova remnants ID X-RAY; SN-1987A AB We describe and model high-velocity (approximate to 15,000 km s(-1)) Ly alpha and H alpha emission from the supernova remnant SNR 1987A seen in 1997 September and October with the Space Telescope Imaging Spectrograph. Part of this emission comes from a reverse shock located at approximate to 75% of the radius of the inner boundary of the inner circumstellar ring and confined within +/- 30 degrees of the equatorial plane. Departure from axisymmetry in the Ly alpha and H alpha emission correlates with that seen in nonthermal radio emission and reveals an asymmetry in the circumstellar gas distribution. We also see diffuse high-velocity Ly alpha emission from supernova debris inside the reverse shock that may be due to excitation by nonthermal particles accelerated by the shock. C1 Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. NASA, Lab Astron & Space Phys, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Virginia, Dept Astron, Charlottesville, VA 22903 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Stockholm Observ, S-13336 Saltsjobaden, Sweden. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Natl Opt Astron Observ, Cerro Tololo Interamer Observ, La Serena, Chile. Mt Stromlo & Siding Spring Observ, Weston, ACT, Australia. Univ Texas, Dept Astron, Austin, TX 78712 USA. Univ Texas, McDonald Observ, Austin, TX 78712 USA. RP Michael, E (reprint author), Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. NR 11 TC 37 Z9 37 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 DEC 20 PY 1998 VL 509 IS 2 BP L117 EP L120 DI 10.1086/311780 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DJ UT WOS:000079250800014 ER PT J AU Perna, R Loeb, A AF Perna, R Loeb, A TI Constraining the beaming of gamma-ray bursts with radio surveys SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts ID COSMOLOGICAL FIREBALL MODEL; 28 FEBRUARY 1997; AFTERGLOW; REDSHIFT; STARS; FIELD AB The degree of beaming in gamma-ray bursts (GRBs) is currently unknown. The uncertainty in the gamma-ray-beaming angle, theta(b), leaves the total energy release (proportional to theta(b)(2)) and the event rate per galaxy (proportional to theta(b)(-2)) unknown to within orders of magnitude. Since the delayed radio emission of GRB sources originates from a mildly relativistic shock and receives only weak relativistic beaming, the rate of radio-selected transients with no GRB counterparts can be used to set an upper limit on theta(b)(-2). We find that a VLA survey with a sensitivity of similar to 0.1 mJy at 10 GHz could identify greater than or similar to 2 x 10(4) (theta(b)/10 degrees)(-2) radio afterglows across the sky if each source is sampled at least twice over a period of 1 month or longer. From the total number of greater than or similar to 0.1 mJy sources observed at 8.44 GHz and the fraction of fading sources at 1.44 GHz, we get the crude limit theta(b) greater than or similar to 6 degrees. 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 32 TC 37 Z9 37 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1998 VL 509 IS 2 BP L85 EP L88 DI 10.1086/311784 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DJ UT WOS:000079250800006 ER PT J AU Huber, BT AF Huber, BT TI Perspectives - Paleoclimate - Tropical paradise at the Cretaceous poles? SO SCIENCE LA English DT Editorial Material ID CLIMATE C1 Smithsonian Inst, Dept Paleobiol, NHB MRC 121, Washington, DC 20560 USA. RP Huber, BT (reprint author), Smithsonian Inst, Dept Paleobiol, NHB MRC 121, Washington, DC 20560 USA. NR 13 TC 76 Z9 78 U1 0 U2 7 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 DEC 18 PY 1998 VL 282 IS 5397 BP 2199 EP 2200 DI 10.1126/science.282.5397.2199 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 150CR UT WOS:000077645800027 ER PT J AU Chen, W Novick, SE McCarthy, MC Thaddeus, P AF Chen, W Novick, SE McCarthy, MC Thaddeus, P TI Microwave spectroscopy of the 2,4-pentadiynyl radical: H2C-C C-C CH SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SPECTRA AB The 2,4-pentadiynyl radical, H2C-C=C-C=CH, was detected in a pulsed-discharge supersonic molecular beam by Fourier transform microwave spectroscopy. Four successive rotational transitions, N = 2-1 through N = 5-4 in the K-a = 0 ladder were observed between 8 and 22 GHz. A total of 48 hyperfine components were measured and assigned with an uncertainty of 5 kHz. Seven spectroscopic constants, including rotational and centrifugal distortion constants, the spin-rotation constant, and hyperfine coupling constants for the methylenic and acetylenic protons were determined to high accuracy. (C) 1998 American Institute of Physics. [S0021-9606(98)01347-6]. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Wesleyan Univ, Dept Chem, Middletown, CT 06459 USA. RP Chen, W (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI McCarthy, Michael/0000-0001-9142-0008 NR 23 TC 9 Z9 9 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 15 PY 1998 VL 109 IS 23 BP 10190 EP 10194 DI 10.1063/1.477712 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 147BZ UT WOS:000077469200012 ER PT J AU Stancil, PC Lepp, S Dalgarno, A AF Stancil, PC Lepp, S Dalgarno, A TI The deuterium chemistry of the early universe SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; early universe; molecular processes; nuclear reactions, nucleosynthesis, abundances ID INTERSTELLAR MOLECULAR SHOCKS; NONRADIATIVE CHARGE-TRANSFER; RADIATIVE ASSOCIATION; DISSOCIATIVE RECOMBINATION; HYDROGEN PLASMAS; BARYON DENSITY; CROSS-SECTIONS; AB-INITIO; CLOUDS; FRACTIONATION AB The chemistry of deuterium, as well as that of hydrogen and helium, in the postrecombination era of the expanding early universe is presented. A thorough survey of all potentially important gas-phase reactions involving the primordial elements produced in the Big Bang, with a particular emphasis on deuterium, is given. The reaction set, consisting of 144 processes, is used in a nonequilibrium chemistry model to follow the production of primordial molecules in the postrecombination era. It is found that significant deuterium fractionation occurs for HD+, HD, and H2D+, while the abundance of D+ is reduced compared to the proton abundance. Even with the enhanced fractionation of H2D+, its abundance is predicted to be too small to cause any interesting cosmological consequences, such as possible attenuation of spatial anisotropies in the cosmic background radiation held, detections of the epochs of reionization and reheating, or constraints on the primordial deuterium abundance. HD, being the second most abundant primordial molecule after H-2, may play a role in subsequent structure formation because of its cooling radiation. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Nevada, Dept Phys, WM Keck Lab Computat Phys, Las Vegas, NV 89154 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Oak Ridge Natl Lab, Div Phys, POB 2008, Oak Ridge, TN 37831 USA. EM stancil@mail.phy.ornl.gov; lepp@physics.univ.edu; sdalgarno@cfa.harvard.edu NR 73 TC 166 Z9 166 U1 1 U2 7 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 DEC 10 PY 1998 VL 509 IS 1 BP 1 EP 10 DI 10.1086/306473 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DE UT WOS:000079250400001 ER PT J AU Garnavich, PM Jha, S Challis, P Clocchiatti, A Diercks, A Filippenko, AV Gilliland, RL Hogan, CJ Kirshner, RP Leibundgut, B Phillips, MM Reiss, D Riess, AG Schmidt, BP Schommer, RA Smith, RC Spyromilio, J Stubbs, C Suntzeff, NB Tonry, J Carroll, SM AF Garnavich, PM Jha, S Challis, P Clocchiatti, A Diercks, A Filippenko, AV Gilliland, RL Hogan, CJ Kirshner, RP Leibundgut, B Phillips, MM Reiss, D Riess, AG Schmidt, BP Schommer, RA Smith, RC Spyromilio, J Stubbs, C Suntzeff, NB Tonry, J Carroll, SM TI Supernova limits on the cosmic equation of state SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; cosmology : theory; supernovae : general ID LIGHT-CURVE SHAPES; COSMOLOGICAL CONSTANT; IA SUPERNOVAE; UNIVERSE; ANISOTROPIES AB We use Type Ia supernovae studied by the High-z Supernova Search Team to constrain the properties of an energy component that may have contributed to accelerating the cosmic expansion. We find that for a flat geometry the equation-of-state parameter for the unknown component, alpha(x) = P-x/rho(x), must be less than -0.55 (95% confidence) for any value of Omega(m), and it is further limited to alpha(x) < -0.60 (95% confidence) if Omega(m), is assumed to be greater than 0.1. These values are inconsistent with the unknown component being topological defects such as domain walls, strings, or textures. The supernova (SN) data are consistent with a cosmological constant (alpha(x) = -1) or a scalar field that has had, on average, an equation-of-state parameter similar to the cosmological constant value of -1 over the redshift range of z approximate to 1 to the present. SN and cosmic microwave background observations give complementary constraints on the densities of matter and the unknown component. If only matter and vacuum energy are considered, then the current combined data sets provide direct evidence for a spatially flat universe with Omega(tot) = Omega(m) + Omega(Lambda) = 0.94 +/- 0.26 (1 sigma). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Pontificia Univ Catolica Chile, Dept Astron & Astrophis, Santiago 22, Chile. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. European So Observ, D-8046 Garching, Germany. Cerro Tololo Interamer Observ, La Serena, Chile. Mt Stromlo & Siding Spring Observ, Woden, ACT 2606, Australia. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Stubbs, Christopher/C-2829-2012; OI Stubbs, Christopher/0000-0003-0347-1724; Schmidt, Brian/0000-0001-6589-1287 NR 54 TC 581 Z9 584 U1 2 U2 6 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 DEC 10 PY 1998 VL 509 IS 1 BP 74 EP 79 DI 10.1086/306495 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DE UT WOS:000079250400008 ER PT J AU O'Brien, PT Dietrich, M Leighly, K Alloin, D Clavel, J Crenshaw, DM Horne, K Kriss, GA Krolik, JH Malkan, MA Netzer, H Peterson, BM Reichert, GA Rodriguez-Pascual, PM Wamsteker, W Anderson, KSJ Bochkarev, NG Cheng, FZ Filippenko, AV Gaskell, CM George, IM Goad, MR Ho, LC Kaspi, S Kollatschny, W Korista, KT MacAlpine, G Marlow, D Martin, PG Morris, SL Pogge, RW Qian, BC Recondo-Gonzalez, MC Espinosa, JMR Santos-Lleo, M Shapovalova, AI Shull, JM Stirpe, GM Sun, WH Turner, TJ Vio, R Wagner, S Wanders, I Wills, KA Wu, H Xue, SJ Zou, ZL AF O'Brien, PT Dietrich, M Leighly, K Alloin, D Clavel, J Crenshaw, DM Horne, K Kriss, GA Krolik, JH Malkan, MA Netzer, H Peterson, BM Reichert, GA Rodriguez-Pascual, PM Wamsteker, W Anderson, KSJ Bochkarev, NG Cheng, FZ Filippenko, AV Gaskell, CM George, IM Goad, MR Ho, LC Kaspi, S Kollatschny, W Korista, KT MacAlpine, G Marlow, D Martin, PG Morris, SL Pogge, RW Qian, BC Recondo-Gonzalez, MC Espinosa, JMR Santos-Lleo, M Shapovalova, AI Shull, JM Stirpe, GM Sun, WH Turner, TJ Vio, R Wagner, S Wanders, I Wills, KA Wu, H Xue, SJ Zou, ZL TI Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. XIII. Ultraviolet observations of the broad-line radio galaxy 3C 390.3 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (3C 390.3); ultraviolet : galaxies ID SHORT-TIMESCALE VARIABILITY; MULTIWAVELENGTH OBSERVATIONS; X-RAY; EMISSION-LINES; OPTICAL WAVELENGTHS; ACCRETION DISKS; UV CONTINUUM; NGC-5548; NGC-4151; 3C-390.3 AB As part of an extensive multiwavelength monitoring campaign, the Inter national Ultraviolet Explorer satellite was used to observe the broad-line radio galaxy 3C 390.3 during the period 1994 December 31-1996 March 5. Spectra were obtained every 6-10 days. The UV continuum varied by a factor of 7 through the campaign, while the broad emission lines varied by factors of 2-5. Unlike previously monitored Seyfert 1 galaxies, in which the X-ray continuum generally varies with a larger amplitude than the UV, in 3C 390.3 the UV continuum light curve is similar in both amplitude and shape to the X-ray light curve observed by ROSAT. The UV broad emission-line variability lags that of the UV continuum by 35-70 days for Ly alpha and C rv, values larger than those found for Seyfert 1 galaxies of comparable UV luminosity. These lags are also larger than those found for the Balmer lines in 3C 390.3 over the same period. The red and blue wings of C rv and Ly alpha vary in phase, suggesting that radial motion does not dominate the kinematics of the UV line-emitting gas. Comparison with archival data provides evidence for velocity-dependent changes in the Ly alpha and C rv line profiles, indicating evolution in the detailed properties and/or distribution of the broad-line emitting gas. C1 Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Landessternwarte, D-69117 Heidelberg, Germany. Columbia Univ, Astrophys Lab, New York, NY 10027 USA. Ctr Etud Saclay, Serv Astrophys, F-91191 Gif Sur Yvette, France. European Space Agcy, ISO Project, Madrid 28080, Spain. NASA, Goddard Space Flight Ctr, Comp Sci Corp, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Univ St Andrews, Sch Phys & Astron, St Andrews KYI16 9SS, Fife, Scotland. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Calif Los Angeles, Dept Astron, Los Angeles, CA 90024 USA. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Wise Observ, IL-69978 Tel Aviv, Israel. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. ESA IUE Observ, Madrid 28080, Spain. New Mexico State Univ, Dept Astron, Dept 4500, Las Cruces, NM 88003 USA. Moscow MV Lomonosov State Univ, Sternberg Astron Inst, Moscow 119899, Russia. Univ Sci & Technol, Ctr Astrophys, Hefei, Anhui, Peoples R China. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Nebraska, Dept Phys & Astron, Lincoln, NE 68588 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Sternwarte Gottingen, D-37083 Gottingen, Germany. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. Univ Manchester, Nuffield Radio Astron Lab, Jodrell Bank, Macclesfield SK11 9DL, Cheshire, England. Univ Toronto, Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada. Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. Chinese Acad Sci, Shanghai Astron Observ, Shanghai 20030, Peoples R China. LAEFF, E-28080 Madrid, Spain. Russian Acad Sci, Special Astrophys Observ, Nizhni Arkhyz 357147, Karachaj Cherkn, Russia. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. Osservatorio Astron Bologna, I-40126 Bologna, Italy. Natl Cent Univ, Inst Astron, Chungli 32054, Taiwan. Chinese Acad Sci, Beijing Astron Observ, Beijing 100080, Peoples R China. RP O'Brien, PT (reprint author), Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England. RI Morris, Simon/G-7981-2011; Recondo, Carmen/B-1215-2012; Stirpe, Giovanna/O-9393-2015; OI Morris, Simon/0000-0003-4866-110X; Recondo, Carmen/0000-0001-9813-6798; Stirpe, Giovanna/0000-0002-3702-8731; Gaskell, C/0000-0003-4888-2009 NR 57 TC 67 Z9 68 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 DEC 10 PY 1998 VL 509 IS 1 BP 163 EP 176 DI 10.1086/306464 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DE UT WOS:000079250400016 ER PT J AU Park, S Finley, JP Dame, TM AF Park, S Finley, JP Dame, TM TI Evidence for the Galactic X-ray bulge. II. SO ASTROPHYSICAL JOURNAL LA English DT Article DE diffuse radiation; Galaxy : structure; ISM : clouds; ISM : structure; X-rays : ISM ID MOLECULAR CLOUDS; MILKY-WAY; CO SURVEY; ROSAT; SHADOWS; MAPS; SKY AB A mosaic of five ROSAT PSPC-pointed observations in the Galactic plane (I similar to 25 degrees) reveals X-ray shadows in the 0.5-2.0 keV band cast by distant molecular clouds. The observed on-cloud and off-cloud X-ray fluxes indicate that similar to 15% and similar to 37% of the diffuse X-ray background in this direction in the 3/4 and 1.5 keV bands, respectively, originates behind the molecular gas that is located at similar to 3 kpc from the Sun. The implication of the derived background X-ray flux beyond the absorbing molecular cloud is consistent with, and lends further support to, recent observations of a Galactic X-ray bulge. C1 Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Park, S (reprint author), Purdue Univ, Dept Phys, 1396 Phys Bldg, W Lafayette, IN 47907 USA. NR 25 TC 10 Z9 10 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1998 VL 509 IS 1 BP 203 EP 211 DI 10.1086/306468 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DE UT WOS:000079250400019 ER PT J AU Torrelles, JM Gomez, JF Garay, G Rodriguez, LF Curiel, S Cohen, RJ Ho, PTP AF Torrelles, JM Gomez, JF Garay, G Rodriguez, LF Curiel, S Cohen, RJ Ho, PTP TI Systems with H2O maser and 1.3 centimeter continuum emission in Cepheus A SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (Cepheus A); ISM : jets and outflows; ISM : molecules; radio continuum : stars; stars : pre-main-sequence ID STAR-FORMING REGION; HERBIG-HARO OBJECTS; THERMAL RADIO JET; A HW2; OUTFLOW; BIPOLAR; SCALE; EAST; OH AB We report continuum (1.3 cm) and H2O maser line observations, made with the Very Large Array (A configuration), toward the cluster of radio continuum sources in the star-forming region Cepheus A East. The 1.3 cm continuum emission is detected toward HW2, HW3b, HW3c, HW3d, and HW9. In addition, a new continuum source (Cep A:VLA 1), undetected previously, is observed at this wavelength. We detected three spatial clusters of H2O masers that are associated with the 1.3 cm continuum sources HW2, HW3b, and HW3dii (the brightest component of HW3d), indicating that these objects may harbor an energy source as suggested by Garay and coworkers. The spatial distribution of the H2O masers with respect to the continuum emission is different in each one of these objects. Toward source HW2 the H2O masers are spread over similar to 1 " and aligned in a direction almost perpendicular to the associated radio jet. In HW3b the H2O masers are spread over a more compact region (-0." 5) and aligned along the major axis of the elongated radio continuum emission. The masers associated with the compact object HW3dii are distributed over a compact region (similar to 0." 5) but do not show any clear spatial trend. By comparing the H2O (this paper) and OH maser distributions in the region, we propose that object HW2, with the strongest H2O-OH maser activity, could represent the "oldest" young stellar object of the region, while HW3b, with no reported OH maser activity, could be the "youngest" source of these three objects. C1 CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. INTA, Lab Astrofis Espacial & Fis Fundamental, E-28080 Madrid, Spain. Univ Chile, Dept Astron, Santiago, Chile. Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico. Univ Manchester, Nuffield Radio Astron Labs, Jodrell Bank, Macclesfield SK11 9DL, Cheshire, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Torrelles, JM (reprint author), Univ Illes Balears, CSIC, Inst Mediterraneo Estudios Avanzados, E-07071 Palma de Mallorca, Spain. RI Garay, Guido/H-8840-2013; Gomez, Jose Francisco/D-8392-2016; OI Garay, Guido/0000-0003-1649-7958; Gomez, Jose Francisco/0000-0002-7065-542X; Torrelles, Jose Maria/0000-0002-6896-6085 NR 33 TC 44 Z9 44 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 DEC 10 PY 1998 VL 509 IS 1 BP 262 EP 269 DI 10.1086/306485 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DE UT WOS:000079250400025 ER PT J AU Di Francesco, J Evans, NJ Harvey, PM Mundy, LG Butner, HM AF Di Francesco, J Evans, NJ Harvey, PM Mundy, LG Butner, HM TI High-resolution far-infrared studies of intermediate-mass pre-main-sequence objects SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; stars : pre-main-sequence ID HERBIG AE/BE STARS; DENSE CORES; NONTHERMAL MOTIONS; DUST; LKH-ALPHA-198; MILLIMETER; MODELS; CLOUD; DISKS; LINE AB We have obtained high-resolution far-infrared maps of nine regions with 10 Herbig Ae/Be stars (intermediate-mass pre-main-sequence stars). Similar maps were obtained for 10 embedded IRAS sources with S-v(100 mu m) > S-v(60 mu m) and L similar to 200 L., which are possible evolutionary precursors of Herbig Ae/Be stars. Single far-infrared sources were found in most maps. The embedded sources have positions in agreement with those of the IRAS PSC, but some of the Herbig Ae/Be stars are offset significantly from the position of peak far-infrared emission. For all objects where it was possible to obtain 100 mu m flux densities, they are consistent with those observed by IRAS, but derived 50 mu m Aux densities are larger than expected. The far-infrared maps reveal that objects in at least 17 of 19 emission regions are significantly extended at the 30 "-40 " resolution of the Kuiper Airborne Observatory at 100 mu m. Only sources associated with AB Aur and possibly IRAS 05338-0624 have unresolved far-infrared emission. Detailed analyses of the flux densities and positions from our maps suggest the far-infrared emission in regions with Herbig Ae/Be stars may not immediately surround these stars in all cases. Instead, far-infrared emission from these objects may originate from dust heated externally by the Herbig stars, or from dust heated internally by other sources. For other objects arguably surrounded by far-infrared emission, the Herbig stars or embedded IRAS objects have similar mean deconvolved sizes (i.e., 0.10-0.15 pc), but possibly have different mean deconvolved shapes (i.e., aspect ratios). Thus, far-infrared emission here may originate from flattened dust envelopes; the appearance of a far-infrared object as either a Herbig Ae/Be star or an embedded IRAS source may be merely a matter of viewing orientation. C1 Univ Texas, Austin, TX 78712 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Di Francesco, J (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS42, Cambridge, MA 02138 USA. OI Butner, Harold/0000-0003-4899-2064 NR 30 TC 24 Z9 24 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 DEC 10 PY 1998 VL 509 IS 1 BP 324 EP 349 DI 10.1086/306479 PN 1 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DE UT WOS:000079250400030 ER PT J AU van Ballegooijen, AA Nisenson, P Noyes, RW Lofdahl, MG Stein, RF Nordlund, A Krishnakumar, V AF van Ballegooijen, AA Nisenson, P Noyes, RW Lofdahl, MG Stein, RF Nordlund, A Krishnakumar, V TI Dynamics of magnetic flux elements in the solar photosphere SO ASTROPHYSICAL JOURNAL LA English DT Article DE convection; Sun : corona; Sun : granulation; Sun : magnetic fields ID TURBULENT COMPRESSIBLE CONVECTION; CORONAL HEATING MECHANISMS; NETWORK BRIGHT POINTS; ACTIVE REGIONS; QUIET PHOTOSPHERE; FACULAR POINTS; SCALING LAW; TUBES; ENERGY; FIELDS AB The interaction of magnetic fields and convection is investigated in the context of the coronal heating problem. We study the motions of photospheric magnetic elements using a time series of high-resolution G-band and continuum filtergrams obtained at the Swedish Vacuum Solar Telescope at La Palma. The G-band images show bright points arranged in linear structures ("filigree") located in the lanes between neighboring granule cells. We measure the motions of these bright points using an object tracking technique, and we determine the autocorrelation function describing the temporal variation of the bright point velocity. The correlation time of the velocity is about 100 s. To understand the processes that determine the spatial distribution of the bright points, we perform simulations of horizontal motions of magnetic flux elements in response to solar granulation flows. Models of the granulation flow are derived from the observed granulation intensity images using a simple two-dimensional model that includes both inertia and horizontal temperature gradients; the magnetic flux elements are assumed to be passively advected by this granulation flow. The results suggest that this passive advection model is in reasonable agreement with the observations, indicating that on a timescale of I hr the flux tubes are not strongly affected by their anchoring at large depth. Finally we use potential-held modeling to extrapolate the magnetic and velocity fields to larger height. We find that the velocity in the chromosphere can be locally enhanced at the separatrix surfaces between neighboring flux tubes. The predicted velocities are several km s(-1), significantly larger than those of the photospheric flux tubes. The implications of these results for coronal heating are discussed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Lockheed Martin Missiles & Space, Ctr Adv Technol, Palo Alto, CA 94304 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Copenhagen Univ Observ, DK-1350 Copenhagen, Denmark. Indian Inst Astrophys, Bangalore 560034, Karnataka, India. RP van Ballegooijen, AA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Nordlund, Aake/M-4528-2014; OI Nordlund, Aake/0000-0002-2219-0541; Lofdahl, Mats/0000-0002-2472-5677; van Ballegooijen, Adriaan/0000-0002-5622-3540 NR 77 TC 87 Z9 87 U1 1 U2 3 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 DEC 10 PY 1998 VL 509 IS 1 BP 435 EP 447 DI 10.1086/306471 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DE UT WOS:000079250400037 ER PT J AU Knowlton, N Weigt, LA AF Knowlton, N Weigt, LA TI New dates and new rates for divergence across the Isthmus of Panama SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE allozymes; Alpheus; COI; molecular clock; mtDNA; Panama ID MITOCHONDRIAL-DNA EVOLUTION; GENETIC-DIVERGENCE; SPECIATION; DIVERSITY; SUPPORT; PACIFIC AB Sister species separated by the Isthmus of Panama have been widely used to estimate rates of molecular evolution. These estimates are based on the assumption that geographic isolation occurred nearly simultaneously for most taxa, when connections between the Caribbean and eastern Pacific closed approximately three million years ago. Here we show that this assumption is invalid for the only genus for which many taxa and multiple genetic markers have been analysed. Patterns of divergence exhibited by allozymes and the mitochondrial COI gene are highly concordant for 15 pairs of snapping shrimp in the genus Alpheus, indicating that they provide a reasonable basis for estimating time since cessation of gene flow The extent of genetic divergence between pairs of sister species varied over fourfold. Sister species from mangrove environments showed the least divergence, as would be expected if these were among the last habitats to be divided. Using this pair yields a rate of sequence divergence of 1.4% per one million years, with implied times of separation for the 15 pairs of 3-18 million years ago. Many past studies may have overestimated rates of molecular evolution because they sampled pairs that were separated well before final closure of the Isthmus. C1 Smithsonian Trop Res Inst, Balboa, Panama. Field Museum Nat Hist, Chicago, IL 60605 USA. RP Knowlton, N (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. EM knowlton@naos.si.edu NR 44 TC 513 Z9 529 U1 9 U2 76 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 EI 1471-2954 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD DEC 7 PY 1998 VL 265 IS 1412 BP 2257 EP 2263 PG 7 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 149GW UT WOS:000077597600003 ER PT J AU Marra, PP Hobson, KA Holmes, RT AF Marra, PP Hobson, KA Holmes, RT TI Linking winter and summer events in a migratory bird by using stable-carbon isotopes SO SCIENCE LA English DT Article ID REDSTARTS SETOPHAGA-RUTICILLA; BODY SIZE; ARRIVAL; EVOLUTION; CONSEQUENCES; DIMORPHISM; FINCHES; GROUNDS; DATE; TIME AB For migratory birds, early arrival and physical condition on the breeding grounds are important determinants of reproductive success and fitness. Differences in arrival times often exceed a month, and Later arriving individuals are often in poorer condition. Habitat-specific isotopic signatures indicate that the quality of winter habitats occupied by American redstarts (Setophaga ruticilla) determines their physical condition and spring departure dates, which in turn result in variable arrival schedules and condition on temperate breeding grounds. These findings link events in tropical winter grounds with those in temperate breeding areas for a migratory songbird and provide evidence that winter habitats may be limiting. C1 Dartmouth Coll, Dept Biol Sci, Hanover, NH 03755 USA. Canadian Wildlife Serv, Prairie & No Wildlife Res Ctr, Saskatoon, SK S7N OX4, Canada. RP Marra, PP (reprint author), Smithsonian Inst, Natl Zool Pk, Smithsonian Migratory Bird Ctr, Washington, DC 20008 USA. EM pmarra@nzp.si.edu NR 31 TC 569 Z9 588 U1 11 U2 137 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 DEC 4 PY 1998 VL 282 IS 5395 BP 1884 EP 1886 DI 10.1126/science.282.5395.1884 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 144WG UT WOS:000077338100047 ER PT J AU Lovejoy, NR Bermingham, E Martin, AP AF Lovejoy, NR Bermingham, E Martin, AP TI Marine incursion into South America SO NATURE LA English DT Letter ID ANDEAN TECTONICS C1 Cornell Univ, Ecol & Systemat Sect, Ithaca, NY 14853 USA. Smithsonian Trop Res Inst, Naos Marine Lab, Balboa, Panama. Univ Colorado, Dept EPOB, Boulder, CO 80309 USA. RP Lovejoy, NR (reprint author), Cornell Univ, Ecol & Systemat Sect, Corson Hall, Ithaca, NY 14853 USA. NR 11 TC 117 Z9 124 U1 3 U2 9 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD DEC 3 PY 1998 VL 396 IS 6710 BP 421 EP 422 DI 10.1038/24757 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 145KL UT WOS:000077370100035 ER PT J AU Ortner, DJ AF Ortner, DJ TI T. Dale Stewart (1901-1997): Anthropologist, administrator, educator, gentleman - Obituary SO AMERICAN ANTHROPOLOGIST LA English DT Biographical-Item C1 Smithsonian Inst, Washington, DC 20560 USA. Univ Bradford, Bradford BD7 1DP, W Yorkshire, England. RP Ortner, DJ (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 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 DEC PY 1998 VL 100 IS 4 BP 990 EP 994 DI 10.1525/aa.1998.100.4.990 PG 5 WC Anthropology SC Anthropology GA 187YE UT WOS:000079815800016 ER PT J AU Ryan, MJ Rand, AS AF Ryan, MJ Rand, AS TI Evoked vocal response in male tungara frogs: pre-existing biases in male responses? SO ANIMAL BEHAVIOUR LA English DT Article ID SEXUAL SELECTION; PHYSALAEMUS-PUSTULOSUS; SENSORY EXPLOITATION; PREEXISTING BIAS; FEMALE PREFERENCE; MATE CHOICE; EVOLUTION; SYSTEM; RECOGNITION; REPERTOIRE AB Female tungara frogs, Physalaemus pustulosus, are preferentially attracted to a whine-chuck advertisement call over a simple whine (Rand Sr Ryan 1981, Zeitschrift fur Tierpsychologie, 57, 209-214). Females also show phonotactic preferences for the whine when a number of other heterospecific or artificial stimuli are added to it, and these calls tend to be as attractive to females as a whine-chuck (Ryan It Rand 1990, Evolution, 44, 305-314). We tested male tungara frogs with the same suite of stimuli using evoked vocal responses as a bioassay to examine sexual differences in responses to signal variation. A whine-chuck elicited greater responses from males than a whine-only. Artificial and heterospecific stimuli that enhanced call attractiveness to females also elicited greater vocal responses from males and, as with females, the effects of these stimuli were similar to that of the whine-chuck. Thus, in both sexes there are pre-existing biases for a suite of stimuli not produced by conspecifics. (C) 1998 The Association for the Study of Animal Behaviour. C1 Univ Texas, Dept Zool, Austin, TX 78712 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Ryan, MJ (reprint author), Univ Texas, Dept Zool, Austin, TX 78712 USA. EM mryan@mail.utexas.edu NR 42 TC 40 Z9 41 U1 1 U2 12 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 DEC PY 1998 VL 56 BP 1509 EP 1516 DI 10.1006/anbe.1998.0928 PN 6 PG 8 WC Behavioral Sciences; Zoology SC Behavioral Sciences; Zoology GA 158RF UT WOS:000078129400023 ER PT J AU Anglada, G Villuendas, E Estalella, R Beltran, MT Rodriguez, LF Torrelles, JM Curiel, S AF Anglada, G Villuendas, E Estalella, R Beltran, MT Rodriguez, LF Torrelles, JM Curiel, S TI Spectral indices of centimeter continuum sources in star-forming regions: Implications on the nature of the outflow exciting sources SO ASTRONOMICAL JOURNAL LA English DT Article DE ISM : jets and outflows; radio continuum; stars : formation ID HERBIG-HARO OBJECTS; YOUNG STELLAR OBJECTS; BIPOLAR MOLECULAR OUTFLOWS; RADIO-CONTINUUM; IRAS SOURCES; DARK CLOUDS; AMMONIA OBSERVATIONS; VLA OBSERVATIONS; PROPER MOTIONS; L1641 REGION AB We present 6 cm VLA observations of nine regions with molecular or HH outflows that appear to be driven by young stellar objects of low bolometric luminosity. Radio continuum emission at 3.6 cm had been detected previously toward the center of symmetry of 13 outflows in these regions. With the new 6 cm observations we have been able to estimate the spectral index in the 6 to 3.6 cm wavelength range for 11 of these outflow central (Class 0 and Class I) sources. All the spectral indices obtained for these central sources are positive and consistent with partially thick thermal free-free emission. We discuss this result in relation to the current models for the origin of centimeter radio continuum emission in outflow sources. In particular, we find that the observed flux densities of these sources fit very well in the observational correlation between the radio continuum luminosity and the momentum rate of the outflow, and that the results are consistent with the central sources being thermal radio jets. Our data suggest that the ionized part of the jets begins at a distance less than or similar to 10 AU from the star. In addition, we have derived a positive value for the spectral index of HH 32A, indicative of partially thick thermal emission. For the remaining sources detected in the nine fields observed, our results indicate that the emission is, in general, nonthermal, as expected for background extragalactic sources. However, a few of these sources could be related to the star-forming regions studied. C1 CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Univ Barcelona, Dept Astron & Meteorol, E-08028 Barcelona, Spain. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico. Univ Illes Balears, CSIC, Inst Mediterraneo Estudios Avanzados, E-07071 Palma de Mallorca, Spain. Univ Nacl Autonoma Mexico, Inst Astron, Morelia, Michoacan, Mexico. RP Anglada, G (reprint author), CSIC, Inst Astrofis Andalucia, Apdo Correos 3004, E-18080 Granada, Spain. OI Beltran Sorolla, Maria Teresa/0000-0003-3315-5626; Torrelles, Jose Maria/0000-0002-6896-6085 NR 91 TC 112 Z9 112 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 1998 VL 116 IS 6 BP 2953 EP 2964 DI 10.1086/300637 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 147RQ UT WOS:000077512000027 ER PT J AU Muzerolle, J Hartmann, L Calvet, N AF Muzerolle, J Hartmann, L Calvet, N TI A Br gamma probe of disk accretion in T Tauri stars and embedded young stellar objects SO ASTRONOMICAL JOURNAL LA English DT Article DE stars : pre-main-sequence; techniques : spectroscopic ID SPECTRAL ENERGY-DISTRIBUTIONS; AURIGA MOLECULAR CLOUD; BALMER LINE-PROFILES; MAGNETOSPHERIC ACCRETION; BIRTHLINE; EMISSION; MODELS; EVOLUTION; CLUSTER AB We report on observations of Pa beta and Br gamma for a sample of classical T Tauri stars in Taurus and find a tight correlation between the emission-line luminosities and the accretion luminosity as measured from the hot continuum excess. We use the Br gamma luminosity correlation to calculate accretion luminosities in highly reddened young stars with existing line measurements. The distribution of accretion luminosities is similar in Taurus and Ophiuchus Class II sources. For the deeply embedded Class I objects, the accretion luminosities are in general less than the bolometric luminosities, which implies that the disk accretion rates are significantly lower than the envelope infall rates. We find that the central sources of many Class I objects are quite similar to their Class II counterparts. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Massachusetts, Five Coll Astron Dept, Amherst, MA 01003 USA. Ctr Invest Astron, Merida, Venezuela. RP Muzerolle, J (reprint author), Harvard Smithsonian Ctr Astrophys, Mail Stop 42,60 Garden St, Cambridge, MA 02138 USA. NR 38 TC 222 Z9 222 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 1998 VL 116 IS 6 BP 2965 EP 2974 DI 10.1086/300636 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 147RQ UT WOS:000077512000028 ER PT J AU Mason, BD Henry, TJ Hartkopf, WI ten Brummelaar, T Soderblom, DR AF Mason, BD Henry, TJ Hartkopf, WI ten Brummelaar, T Soderblom, DR TI A multiplicity survey of chromospherically active and inactive stars SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : general; stars : activity; stars : chromospheres ID ICCD SPECKLE OBSERVATIONS; MASS-LUMINOSITY-RELATION; SOLAR-TYPE STARS; BINARY STARS; CLUSTER; TELESCOPE AB Surveys of three samples of solar-type stars, segregated by chromospheric emission level, were made to determine their multiplicity fractions and to investigate the evolution of multiplicity with age. In total, 245 stars were searched for companions with Delta V less than or equal to 3.0 and separations of 0." 035 to 1." 08 using optical speckle interferometry. By incorporating the visual micrometer survey for duplicity of the Lamont-Hussey Observatory, the angular coverage was extended to 5." 0 with no change in the Delta V limit. This magnitude difference allows mass ratios of 0.63 and larger to be detected throughout a search region of 2-127 AU for the stars observed. The 84 primaries observed in the chromospherically active sample are presumably part of a young population and are found to have a multiplicity fraction of 17.9% +/- 4.6%. The sample of 118 inactive, presumably older, primaries were selected and observed using identical methods and are found to have a multiplicity fraction of only 8.5% +/- 2.7%. Given the known link between chromospheric activity and age, these results tentatively imply a decreasing stellar multiplicity fraction from 1 to 4 Gyr, the approximate ages of the two samples. Finally, only two of the 14 very active primaries observed were found to have a companion meeting the survey detection parameters. In this case, many of the systems are either very young, or close, RS CVn type multiples that are unresolvable using the techniques employed here. C1 USN Observ, Washington, DC 20392 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Georgia State Univ, Ctr High Angular Resolut Astron, Atlanta, GA 30303 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Mason, BD (reprint author), USN Observ, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. EM bdm@draco.usno.navy.mil; thenry@recons.harvard.edu; hartkopf@chara.gsu.edu; theo@mtwilson.edu; drs@stsci.edu NR 24 TC 30 Z9 30 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 1998 VL 116 IS 6 BP 2975 EP 2983 DI 10.1086/300654 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 147RQ UT WOS:000077512000029 ER PT J AU Harris, DE Silverman, JD Hasinger, G Lehmann, I AF Harris, DE Silverman, JD Hasinger, G Lehmann, I TI Spatial corrections of ROSAT HRI observations SO ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES LA English DT Article DE techniques : image processing; X-rays : general AB X-ray observations with the ROSAT High Resolution Imager (HRI) often have spatial smearing on the order of 10 " (Morse 1994), This degradation of the intrinsic resolution of the instrument (5 ") can be attributed to errors in the aspect solution associated with the wobble of the space craft or with the reacquisition of the guide stars. We have developed a set of IRAF/PROS and MIDAS/EXSAS routines to minimize these effects. Our procedure attempts to isolate aspect errors that are repeated through each cycle of the wobble. The method assigns a "wobble phase" to each event based on the 402 second period of the ROSAT wobble. The observation is grouped into a number of phase bills and a centroid is calculated for each sub-image, The corrected HRI event list is reconstructed by adding the sub-images which have been shifted to a common source position. This method has shown similar to 30% reduction of the full width half maximum (FWHM) of an X-ray observation of the radio galaxy 3C 120. Additional examples are presented. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Astrophys Inst Potsdam, D-14482 Potsdam, Germany. RP Harris, DE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 3 TC 23 Z9 23 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 DEC PY 1998 VL 133 IS 3 BP 431 EP 436 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 153TM UT WOS:000077848800013 ER PT J AU Stetson, PB Saha, A Ferrarese, L Rawson, DM Ford, HC Freedman, WL Gibson, BK Graham, JA Harding, P Han, MS Hill, RJ Hoessel, JG Huchra, JP Hughes, SMG Illingworth, GD Kelson, DD Kennicutt, RC Madore, BF Mould, JR Phelps, RL Sakai, S Silberman, NA Turner, A AF Stetson, PB Saha, A Ferrarese, L Rawson, DM Ford, HC Freedman, WL Gibson, BK Graham, JA Harding, P Han, MS Hill, RJ Hoessel, JG Huchra, JP Hughes, SMG Illingworth, GD Kelson, DD Kennicutt, RC Madore, BF Mould, JR Phelps, RL Sakai, S Silberman, NA Turner, A TI The extragalactic distance scale key project. XVI. Cepheid variables in an inner field of M101 SO ASTROPHYSICAL JOURNAL LA English DT Article DE Cepheids; galaxies : distances and redshifts; galaxies : individual (M101); galaxies : photometry ID HUBBLE-SPACE-TELESCOPE; H-II REGIONS; STELLAR PHOTOMETRY; PEAK BRIGHTNESS; CCD PHOTOMETRY; CALIBRATION; DISCOVERY; PROGRAM; WFPC2; HST AB We report on the identification of 255 candidate variable stars in a field located some 1.'7 from the center of the late-type spiral galaxy M101 = NGC 5457, based on observations made with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope. Photometric measurements in the F555W and F814W filters-analyzed independently with the DAOPHOT/ALLFRAME and DoPHOT software suites-have been transformed to the Johnson V and Kron-Cousins I standard magnitude systems. Periods and intensity-averaged mean magnitudes for 61 carefully selected candidate Cepheid variables with periods in the range 10-48 days indicate a reddening-corrected mean distance modulus (m - M)(o) = 29.05 +/- 0.14 (if the true modulus of the Large Magellanic Cloud is 18.50 +/- 0.10, and if there is no dependence of the period-luminosity relation on metal abundance); results consistent with this are obtained whether or not the sample is expanded to include a larger fraction of the candidates. Applying a metallicity-dependent correction of +0.16 +/- 0.10 mag would increase this estimate to (m - M)(o) = 29.21 +/- 0.17 mag. C1 Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CALTECH, IPAC, Pasadena, CA 91125 USA. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Inst Adv Studies, Weston Creek, ACT 2611, Australia. Johns Hopkins Univ, Baltimore, MD 21218 USA. Space Telescope Inst, Baltimore, MD 21218 USA. Carnegie Observ, Pasadena, CA 91101 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Wisconsin, Madison, WI 53706 USA. NASA, Astron & Solar Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Raytheon STX Corp, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Royal Greenwich Observ, Cambridge CB3 0EZ, England. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. RP Stetson, PB (reprint author), Dominion Astrophys Observ, 5071 W Saanich Rd, Victoria, BC V8X 4M6, Canada. RI Gibson, Brad/M-3592-2015 OI Gibson, Brad/0000-0003-4446-3130 NR 37 TC 97 Z9 97 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 DEC 1 PY 1998 VL 508 IS 2 BP 491 EP 517 DI 10.1086/306443 PN 1 PG 27 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500005 ER PT J AU Xu, C Hacking, PB Fang, F Shupe, DL Lonsdale, CJ Lu, NY Helou, G Stacey, GJ Ashby, MLN AF Xu, C Hacking, PB Fang, F Shupe, DL Lonsdale, CJ Lu, NY Helou, G Stacey, GJ Ashby, MLN TI Emission features and source counts of galaxies in the mid-infrared SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : luminosity function, mass function; galaxies : photometry; galaxies : statistics; infrared : galaxies ID STAR-FORMATION HISTORY; HUBBLE DEEP FIELD; INTERSTELLAR DUST; REDSHIFT SURVEY; SMALL GRAINS; WIDE-FIELD; EVOLUTION; ISOCAM; SPECTROPHOTOMETRY; MODELS AB In this work we incorporate the newest Infrared Space Observatory (ISO) results on the mid-infrared spectral energy distributions (MIR SEDs) of galaxies into models for the number counts and redshift distributions of MIR surveys. A three-component model, with empirically determined MIR SED templates of (1) a cirrus/photodissociation region component, (2) a starburst component, and (3) an active galactic nucleus (AGN) component, is developed for infrared (3-120 mu m) SEDs of galaxies. The model includes a complete IRAS 25 mu m selected sample of 1406 local galaxies (z less than or equal to 0.1). Results based on these 1406 spectra show that the MIR emission features cause significant effects on the redshift dependence of the K-corrections for fluxes in the WIRE 25 mu m band and ISOCAM 15 mu m band. This in turn will affect deep counts and redshift distributions in these two bands, as shown by the predictions of two evolution models [a luminosity evolution model with L proportional to (1 + z)(3) and a density evolution model with rho proportional to (1 + z)(4)]. Th, dips and bumps on curves of MIR number counts, caused by the emission features, should be useful indicators of the evolution mode. The strong emission features at similar to 6-8 mu m will help the detections of relatively high redshift (z similar to 2) galaxies in MIR surveys. On the other hand, determinations of the evolutionary rate based on the slope of source counts and studies on the large-scale structures using the redshift distribution of MIR sources will have to treat the effects of the MIR emission features carefully. We have also estimated a 15 mu m local luminosity function from the predicted 15 mu m fluxes of the 1406 galaxies using the bivariate (15 mu m vs. 25 mu m luminosities) method. This luminosity function will improve our understanding of the ISOCAM 15 mu m surveys. C1 CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Smithsonian Astrophys Observ, Opt & Infared Astron Div, Cambridge, MA 02138 USA. RP Xu, C (reprint author), CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, 4800 Oak Grove Dr, Pasadena, CA 91125 USA. NR 68 TC 75 Z9 75 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 576 EP 589 DI 10.1086/306424 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500012 ER PT J AU Pariev, VI Bromley, BC AF Pariev, VI Bromley, BC TI Line emission from an accretion disk around a black hole: Effects of disk structure SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; galaxies : active; galaxis : Seyfert; line : profiles ID ACTIVE GALACTIC NUCLEI; X-RAY REFLECTION; SEYFERT-1 GALAXIES; COLD MATTER; IRON LINE; FLUORESCENCE; MCG-6-30-15; SPECTRUM AB The observed iron K alpha fluorescence lines in Seyfert I galaxies provide strong evidence for an accretion disk near a supermassive black hole as a source of the line emission. These lines serve as powerful probes for examining the structure of inner regions of accretion disks. Previous studies of line emission have considered only geometrically thin disks, where the gas moves along geodesics in the equatorial plane of a black hole. Here we extend this work to consider the effects on line profiles from finite disk thickness, radial accretion flow, and turbulence. We adopt the Novikov-Thorne alpha-disk model and find that within this framework turbulent broadening is the dominant new effect. The most prominent change in the skewed, double-horned line profiles is a substantial reduction in the maximum flux at both red and blue peaks. The effect is most pronounced when the inclination angle is large and when the accretion rate is high. Thus, the effects discussed here may be important for future detailed modeling of high-quality observational data. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Theoret Astrophys Grp, Cambridge, MA 02138 USA. RP Pariev, VI (reprint author), PN Lebedev Phys Inst, Leninsky Prospect 53, Moscow 117924, Russia. NR 29 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 DEC 1 PY 1998 VL 508 IS 2 BP 590 EP 600 DI 10.1086/306420 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500013 ER PT J AU Cranmer, SR AF Cranmer, SR TI Non-Maxwellian redistribution in solar coronal Ly alpha emission SO ASTROPHYSICAL JOURNAL LA English DT Article DE line : formation; line : profiles; radiative transfer; solar wind; Sun : corona; Sun : UV radiation ID VELOCITY DISTRIBUTION-FUNCTIONS; TRANSITION REGION; WIND ELECTRONS; ALFVEN WAVES; H-I; PLASMA; MODEL; TEMPERATURE; TRANSPORT; LINE AB This paper presents theoretical models of H I Ly alpha emission from the extended solar corona, taking into account various plasma kinetic effects that induce departures from Maxwellian velocity distributions. Such phenomena as suprathermal tails, strong temperature anisotropies, and skewed or double-peaked distributions have been observed in the solar wind, and UV spectroscopy is beginning to be able to detect their signatures in the corona. For resonantly scattered lines like H I Ly alpha, most of the physics is contained in the frequency-dependent redistribution function. The dependence of this function on the local plasma parameters is presented analytically for four different non-Maxwellian distributions, and optically thin line intensities are computed for a representative model of the fast solar wind. Isotropic power-law "kappa" tails in the velocity distribution should be detectable between 2 and 5 Angstrom from line center. Although existing observations that appear to have broad tails do not resemble those arising from kappa-distributions, their presence is still possible. Anisotropic bi-Maxwellian distributions affect line profile shapes and total intensities via both their parallel and perpendicular components, and it is important to include an accurate description of the photon redistribution for large anisotropies. Skewness caused by a Chapman-Enskog expansion in the conductive heat flux is detectable as a unique non-Gaussian profile shape, but other types of collisionally beamed or skewed distributions may not noticeably affect the emission lines. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Cranmer, SR (reprint author), Smithsonian Astrophys Observ, 60 Garden St,MS 50, Cambridge, MA 02138 USA. NR 92 TC 56 Z9 56 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 DEC 1 PY 1998 VL 508 IS 2 BP 925 EP 939 DI 10.1086/306415 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500049 ER PT J AU Ford, EC van der Klis, M van Paradijs, J Mendez, M Wijnands, R Kaaret, P AF Ford, EC van der Klis, M van Paradijs, J Mendez, M Wijnands, R Kaaret, P TI Discovery of a second kilohertz QPO in the X-ray binary 4U 1735-44 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; stars : individual (4U 1735 -44); stars : neutron; X-rays : stars AB In recent observations with the Rossi X-Ray Timing Explorer, we have detected two simultaneous quasi-periodic oscillation (QPO) peaks in the low-mass X-ray binary and atoll source 4U 1735-44. The lower and higher frequency QPOs have frequencies varying between 632 and 729 Hz and 982 and 1026 Hz, respectively. The fractional rms amplitudes are 3.7%-8.1% and 5.0%-5.8%. The frequency separation between the two QPOs changes from 341 +/- 7 to 296 +/- 12 Hz. The inferred mass accretion rate during our observations is relatively low compared to that during the previous observations, in which only a single QPO was present. There is weak evidence that the frequency of the QPOs correlates with the mass accretion rate, as observed in other binaries. Five X-ray bursts were recorded with no detectable oscillations with upper limits for the rms fraction of 4%-13%. C1 Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. Natl Univ La Plata, Fac Ciencias Astron & Geofis, RA-1900 La Plata, Argentina. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02139 USA. RP Ford, EC (reprint author), Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. RI Mendez, Mariano/C-8011-2012 OI Mendez, Mariano/0000-0003-2187-2708 NR 26 TC 49 Z9 49 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP L155 EP L158 DI 10.1086/311745 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MD UT WOS:000077780600010 ER PT J AU Grogin, NA Geller, MJ Huchra, JP AF Grogin, NA Geller, MJ Huchra, JP TI A complete redshift survey to the Zwicky catalog limit in a 2(h)x15 degrees region around 3C 273 SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE catalogs; galaxies : distances and redshifts; large-scale structure of universe; surveys ID VIRGO CLUSTER AREA; SURFACE-BRIGHTNESS GALAXIES; LYMAN-ALPHA-CLOUDS; SPIRAL GALAXIES; NEUTRAL HYDROGEN; HI OBSERVATIONS; POOR CLUSTERS; SAMPLE; KINEMATICS; 3C-273 AB We compile 1113 redshifts (648 new measurements, 465 from the literature) for Zwicky catalog galaxies in the region (-3.(o)5 less than or equal to delta less than or equal to 8.(o)5, 11.(h)5 less than or equal to alpha less than or equal to 13.(h)5). We include redshifts for 114 component objects in 78 Zwicky catalog multiplets. The redshift survey in this region is 99.5% complete to the Zwicky catalog limit, m(Zw) = 15.7. It is 99.9% complete to m(Zw) = 15.5, the CfA Redshift Survey (CfA2) magnitude limit. The survey region is adjacent to the northern portion of CfA2, overlaps the northernmost slice of the Las Campanas Redshift Survey, includes the southern extent of the Virgo Cluster, and is roughly centered on the QSO 3C 273. As in other portions of the Zwicky catalog, bright and faint galaxies trace the same large-scale structure. 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. EM ngrogin@cfa.harvard.edu; mgeller@cfa.harvard.edu; jhuchra@cfa.harvard.edu NR 86 TC 25 Z9 25 U1 0 U2 0 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 DEC PY 1998 VL 119 IS 2 BP 277 EP 285 DI 10.1086/313164 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 150VW UT WOS:000077687300010 ER PT J AU Dittus, WPJ AF Dittus, WPJ TI Birth sex ratios in toque macaques and other mammals: integrating the effects of maternal condition and competition SO BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY LA English DT Review DE birth sex ratios; sex allocation; mammals; natural population; Macaca sinica; macaques ID LOCAL RESOURCE COMPETITION; BABOONS PAPIO-CYNOCEPHALUS; FEMALE VERVET MONKEYS; MIKUMI-NATIONAL-PARK; MALE RHESUS MACAQUES; MALE-DOMINANCE RANK; WHITE-TAILED DEER; REPRODUCTIVE SUCCESS; PRIMATE POPULATION; JAPANESE MACAQUES AB Mammalian life histories suggest that maternal body condition and social dominance (a measure of resource-holding potential) influence the physical and social development of offspring, and thereby their reproductive success. Predictably, a mother should produce that sex of offspring which contributes most to her fitness (as measured by the number of her grandchildren) and that she is best able to raise within the constraints imposed by her condition, social rank, and environment. Such combined effects were investigated by monitoring variations in body condition (weight) and behavior of female toque macaques, Macccca sinica of Sri Lanka, in a changing forest environment over 18 years. Maternal rank, by itself, had no influence on offspring sex, but did affect maternal body condition. The combined effects of rank and condition indicated the following: mothers in robust condition bore more sons, whereas those in moderate condition bore more daughters, but both effects were expressed most strongly among mothers of high rank. Where the consequences of low rank were felt most acutely, as shown by poor condition, mothers underproduced daughters. Environmental quality directly influenced rank and condition interactions, and thus sex ratios. These relationships, and data from other mammals suggest an empirically and theoretically consistent pattern of sex allocation in mammals. New predictions integrate effects, proposed by Trivers and Willard, that are rooted in male mate competition, which is universal among polygynous mammals, with those of local resource competition (and/or female reproductive competition), which are not universal and differ in intensity between the socioecologies and local environments of different species. C1 Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. Inst Fundamental Studies, Kandy, Sri Lanka. RP Dittus, WPJ (reprint author), 140-12 Mapanawathura Rd, Kandy, Sri Lanka. NR 136 TC 43 Z9 44 U1 6 U2 14 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0340-5443 J9 BEHAV ECOL SOCIOBIOL JI Behav. Ecol. Sociobiol. PD DEC PY 1998 VL 44 IS 3 BP 149 EP 160 DI 10.1007/s002650050527 PG 12 WC Behavioral Sciences; Ecology; Zoology SC Behavioral Sciences; Environmental Sciences & Ecology; Zoology GA 147WN UT WOS:000077520600001 ER PT J AU Kress, WJ Heyer, WR Acevedo, P Coddington, J Cole, D Erwin, TL Meggers, BJ Pogue, M Thorington, RW Vari, RP Weitzman, MJ Weitzman, SH AF Kress, WJ Heyer, WR Acevedo, P Coddington, J Cole, D Erwin, TL Meggers, BJ Pogue, M Thorington, RW Vari, RP Weitzman, MJ Weitzman, SH TI Amazonian biodiversity: assessing conservation priorities with taxonomic data SO BIODIVERSITY AND CONSERVATION LA English DT Article DE biodiversity; Amazonia; geographic information system (GIS); museum collections; species diversity ID ENDEMISM; AREAS AB Data from 3991 records of museum collections representing 421 species of plants, arthropods, amphibians, fish, and primates were analyzed with GIS to identify areas of high species diversity and endemism in Amazonia. Of the 472 1 x 1 degrees grid cells in Amazonia, only nine cells are included in the highest species diversity category (43-67 total species) and nine in the highest endemic species diversity category (4-13 endemic species). Over one quarter of the grid cells have no museum records of any of the organisms in our study. Little correspondence exists between the centers of species diversity identified by our collections-based data and those areas recommended for conservation in an earlier qualitative study of Amazonian biodiversity. Museum collections can play a vital role in identifying species-rich areas for potential conservation in Amazonia, but a concerted and structured effort to increase the number and distribution of collections is needed to take maximum advantage of the information they contain. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RP Kress, WJ (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. NR 17 TC 71 Z9 73 U1 1 U2 14 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0960-3115 J9 BIODIVERS CONSERV JI Biodivers. Conserv. PD DEC PY 1998 VL 7 IS 12 BP 1577 EP 1587 DI 10.1023/A:1008889803319 PG 11 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 187TQ UT WOS:000079804500005 ER PT J AU Randazzo, G Stanley, DJ Di Geronimo, SI Amore, C AF Randazzo, G Stanley, DJ Di Geronimo, SI Amore, C TI Human-induced sedimentological changes in Manzala Lagoon, Nile Delta, Egypt SO ENVIRONMENTAL GEOLOGY LA English DT Article DE Delta lagoons; fish resources; Manzala Lagoon; Nile Delta; pollution; waste water ID LATE QUATERNARY EVOLUTION; HOLOCENE SEQUENCES; RECENT SUBSIDENCE; GEOCHEMISTRY; REGION; MARIUT; PLAIN; LAKE AB The Manzala Lagoon in Egypt's Nile Delta has become a sediment sink of reduced area and depth, with increased contaminant levels. Loss of much-needed fresh to brackish water reserves and decreased fish catches have serious ramifications. Herein, maps of temporal and regional sediment distributions in Manzala incorporate petrological statistical analyses of 200 surficial and short samples. These provide baseline information ed to help implement protection measures for vital wetland. Four periods are considered: 1920s, 1940s, similar to 1965, and 1990. Important depositional changes between 1940s and similar to 1965 resulted anthropogenic effects on this quasi-closed lagoon system, including industrial buildup, wetland conversion to agricultural land, and irrigation waterway development. Further modification from similar to 1965 to 1990 is associated with closure of the Aswan High Dam, continued construction of waterways that discharge waste water into lagoon margins, and marine incursion into the northern lagoon. If current practices continue, the lagoon could be reduced to about one-third of its present area by 2050 AD. C1 Smithsonian Inst, NMNH, Deltas Global Change Program, Washington, DC 20560 USA. Univ Messina, Ist Sci Terra, I-98100 St Agata Messina, Italy. Univ Catania, Ist Policattedra Oceanol & Paleoecol, I-95129 Catania, Italy. RP Stanley, DJ (reprint author), Smithsonian Inst, NMNH, Deltas Global Change Program, Washington, DC 20560 USA. NR 59 TC 16 Z9 16 U1 1 U2 12 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0943-0105 J9 ENVIRON GEOL JI Environ. Geol. PD DEC PY 1998 VL 36 IS 3-4 BP 235 EP 258 PG 24 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 150NW UT WOS:000077672200006 ER PT J AU Briceno, RD Eberhard, WG AF Briceno, RD Eberhard, WG TI Medfly courtship duration: a sexually selected reaction norm changed by crowding SO ETHOLOGY ECOLOGY & EVOLUTION LA English DT Article DE courtship; reaction norm; medfly; sexual selection ID CERATITIS-CAPITATA DIPTERA; MEDITERRANEAN FRUIT-FLY; MATING-BEHAVIOR; TEPHRITIDAE AB The evolutionary effects of crowding on male courtship behavior were studied using wild and mass-reared medflies. Mass-reared strains had been raised under highly crowded conditions in mass-rearing facilities for approximately 75, 180, and 238 generations. Pre-mounting courtship was facultatively shortened in both wild and mass-reared males under conditions of greater crowding. The courtship behavior of males of mass-reared strains was also shorter than that of wild males under similar conditions of crowding. Shorter courtships are probably advantageous for males in crowded conditions because they reduce the likelihood of the courtship being interrupted by other flies. Several types of data indicated that males rather than females were responsible for shortened courtships. We conclude that heritable variation in male courtship behavior has persisted in a wild population despite its overall relatively low genetic variability, and that genetic changes in mass-reared strains have altered the range of facultative adjustments in courtship behavior. 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. NR 24 TC 48 Z9 49 U1 0 U2 1 PU UNIVERSITA DEGLI STUDI DI FIRENZE PI FLORENCE PA ATTN: PROF. F. DESSI-FULGHERI VIA ROMANA 17, 50125 FLORENCE, ITALY SN 0394-9370 J9 ETHOL ECOL EVOL JI Ethol. Ecol. Evol. PD DEC PY 1998 VL 10 IS 4 BP 369 EP 382 PG 14 WC Behavioral Sciences; Zoology SC Behavioral Sciences; Zoology GA 160HB UT WOS:000078223500005 ER PT J AU Wurth, MKR Winter, K Korner, C AF Wurth, MKR Winter, K Korner, C TI In situ responses to elevated CO2 in tropical forest understorey plants SO FUNCTIONAL ECOLOGY LA English DT Article DE atmospheric change; carbon dioxide enrichment; forest dynamics; growth; Panama; solar radiation ID CARBON-DIOXIDE; RAIN-FOREST; GROWTH-RESPONSES; TREE; PHOTOSYNTHESIS; MODEL; COMMUNITIES; SEEDLINGS; ENVIRONMENTS; ECOSYSTEMS AB 1. Plants growing in deep shade and high temperature, such as in the understorey of humid tropical forests, have been predicted to be particularly sensitive to rising atmospheric CO2. We tested this hypothesis in five species whose microhabitat quantum flux density (QFD) was documented as a covariable. After 7 (tree seedlings of Tachigalia versicolor and Beilschmiedia pendula) and 18 months (shrubs Piper cordulatum and Psychotria limonensis, and grass Pharus latifolius) of elevated CO2 treatment (c. 700 mu l litre(-1)) under mean QFD of less than 11 mu mol m(-2) s(-1), ail species produced more biomass (25-76%) under elevated CO2. 2. Total plant biomass tended to increase with microhabitat QFD (daytime means varying from 5 to II mu mol m(-2) s(-1)) but the relative stimulation by elevated CO2 was higher at low QFD except in Pharus. 3. Non-structural carbohydrate concentrations in leaves increased significantly in Pharus (+ 27%) and Tachigalia (+ 40%). 4. The data support the hypothesis that tropical plants growing near the photosynthetic light compensation point are responsive to elevated CO2. An improved plant carbon balance in deep shade is likely to influence understorey plant recruitment and competition as atmospheric CO2 continues to rise. C1 Univ Basel, Inst Bot, CH-4056 Basel, Switzerland. Smithsonian Trop Res Inst, Balboa, Panama. RP Wurth, MKR (reprint author), Univ Basel, Inst Bot, Schonbeinstr 6, CH-4056 Basel, Switzerland. RI Korner, Christian/B-6592-2014 NR 53 TC 50 Z9 56 U1 0 U2 12 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 DEC PY 1998 VL 12 IS 6 BP 886 EP 895 DI 10.1046/j.1365-2435.1998.00278.x PG 10 WC Ecology SC Environmental Sciences & Ecology GA 165NA UT WOS:000078526400004 ER PT J AU Marvin, UB AF Marvin, UB TI Comets, popular culture, and the birth of modern cosmology. 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 DEC PY 1998 VL 89 IS 4 BP 705 EP 706 DI 10.1086/384164 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA 163KB UT WOS:000078403600008 ER PT J AU Crew, S AF Crew, S TI "New raiments of self": African American clothing in the antebellum south SO JOURNAL OF AMERICAN HISTORY LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Crew, S (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION AMER HISTORIANS PI BLOOMINGTON PA 112 N BRYAN ST, BLOOMINGTON, IN 47408 USA SN 0021-8723 J9 J AM HIST JI J. Am. Hist. PD DEC PY 1998 VL 85 IS 3 BP 1067 EP 1068 DI 10.2307/2567254 PG 2 WC History SC History GA 149PB UT WOS:000077613100037 ER PT J AU Stanley, DJ Nir, Y Galili, E AF Stanley, DJ Nir, Y Galili, E TI Clay mineral distributions to interpret Nile cell provenance and dispersal: III. Offshore margin between Nile delta and northern Israel SO JOURNAL OF COASTAL RESEARCH LA English DT Article DE Aswan High Dam; Bardawil lagoon; clay minerals; coastal erosion; Egyptian shelf; Gaza; Israeli rivers; Israeli shelf; Levant margin; Mediterranean; Nile delta; Nile littoral cell; sediment dispersal; Sinai margin; suspended load; Wadi El Arish ID SOUTHEASTERN MEDITERRANEAN COAST; SEDIMENT TRANSPORT; CONTINENTAL-SHELF; QUATERNARY; EVOLUTION; EGYPT; SEA AB Clay assemblages in Holocene sediment on southeast,Mediterranean margins are generally smectite-rich and, in the past, were derived primarily from direct River Nile input to the sea. Depositional patterns in the Nile littoral cell are now undergoing extensive change, largely as a response to closure of the High Dam at Aswan (1964), increased sediment entrapment by canal systems in the Nile delta, and construction of large coastal structures between the Nile delta and Israeli margins. Although information on land-to-sea dispersal by the River Nile and other fluvial and offshore sediment sources to the east remains limited, there appears to be evidence for increased sediment input from erosion of Sinai and Levant shelves and coasts east of the Nile delta. This, the third in a S-part study that focuses on regional clay mineral distributions, was initiated to provide baselines to measure evolving changes of sediment provenance and dispersal patterns on the shelves and upper Nile Cone between the Nile delta and northern Israel. The investigation shows that clay assemblages are not uniformly distributed in the SE Mediterranean, likely a result of several important sediment sources in addition to the Nile. Smectite-rich clay assemblages east of the Nile delta are presently derived from storm wave and coastal current erosion of the Nile delta, reworking of Quaternary deposits along the coast and on the seafloor east of the delta, and from some Israeli rivers between Tel Aviv and Atlit. Kaolinite and illite at offshore sites are supplied in part from erosion of coastal cliff sections, river input between Wadi El Arish in Sinai and the Lebanon-Israel border, and from wind-borne dust from African and Middle East deserts released seaward of the coast. The diverse source terrains that back coastal plains provide laterally variable clay assemblages along the southeastern Mediterranean coast. Presently evolving changes in the volume and mineralogy of sediment transported from the distal Nile region in Egypt, versus those from more proximal coastal sources on Sinai and Levant margins, are likely to be subtle. Post-Aswan High Dam changes of fine-sediment load, composition and dispersal in the eastern Mediterranean should now be determined from water samples and sediment traps set above the seafloor between the coast and upper Nile Cone. Improved quality of information can be derived from clay mineral assemblages in suspended sediment samples in conjunction with geochemical tracers. Moreover, detailed morphologic surveys will provide essential information on altered sediment transport patterns as related to sectors undergoing accelerated coastal erosion. C1 Smithsonian Inst, Deltas Global Change Program, Washington, DC 20560 USA. Geol Survey Israel, IL-95501 Jerusalem, Israel. Israel Antiqu Author, Marine Archaeol Branch, IL-30350 Atlit, Israel. RP Stanley, DJ (reprint author), Smithsonian Inst, Deltas Global Change Program, E-206 NMNH, Washington, DC 20560 USA. NR 59 TC 26 Z9 26 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 WIN PY 1998 VL 14 IS 1 BP 196 EP 217 PG 22 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA YT592 UT WOS:000071622500017 ER PT J AU Chen, ZY Stanley, DJ AF Chen, ZY Stanley, DJ TI Sea-level rise on eastern China's Yangtze delta SO JOURNAL OF COASTAL RESEARCH LA English DT Article DE delta flooding; neolithic sites; peat; radiocarbon dates; relative sea level; sea-level curve; subsidence; Taihu lake; Yangtze delta ID HOLOCENE AB The Yangtze delta is a densely populated, low-lying region highly vulnerable to flooding, high tides and typhoons. All previous studies indicated that relative sea level was higher from similar to 7500-4000 yrs. BP, then lowered and stabilized at about present msl during the past 3000 yrs. To the contrary, we find that sea level has been rising relative to the southern Yangtze delta plain based on new sea-level data derived from dated peats, reassessment of earlier sea-level curves and measurement of delta plain subsidence and analysis of prehistoric habitat bases from similar to 7000 to 3000 yrs. BP. Consequences of this relative rise include difficulty in expelling water from the low-lying delta plain to the coast and associated flood damage. Emplacement of the 3-Gorges Dam on the Yangtze will control flooding of the Yangtze river but decrease sediment accumulation on the delta plain that, in turn, is likely to accelerate saline inundation of this vital breadbasket. C1 E China Normal Univ, Dept Geog, Shanghai 200062, Peoples R China. Smithsonian Inst, Deltas Global Change Program, NMNH E206, Washington, DC 20560 USA. RP Chen, ZY (reprint author), E China Normal Univ, Dept Geog, Shanghai 200062, Peoples R China. NR 27 TC 50 Z9 69 U1 2 U2 11 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 WIN PY 1998 VL 14 IS 1 BP 360 EP 366 PG 7 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA YT592 UT WOS:000071622500031 ER PT J AU Oliveira, EG Srygley, RB Dudley, R AF Oliveira, EG Srygley, RB Dudley, R TI Do neotropical migrant butterflies navigate using a solar compass? SO JOURNAL OF EXPERIMENTAL BIOLOGY LA English DT Article DE butterfly; migration; clock-shift; navigation; orientation; sun compass; Aphrissa statira; Phoebis argante ID HOMING PIGEONS; CLOCK-SHIFT; COMPENSATION; ORIENTATION AB Many tropical butterfly species are well-known for their migratory behaviour. Although these insects can maintain a constant direction throughout the day, the physiological mechanisms of orientation are unknown, It has been argued that tropical migrant butterflies must use a time-compensated sun compass to accomplish their journey, but the crucial experimental manipulations to test this hypothesis have not been conducted. This study reports the results of clock-shift experiments performed with two species of migrating butterflies (Pieridae: Aphrissa statira and Phoebis argante) captured during flight across Lake Gatun, Panama. The observed constant flight bearing of natural controls suggests that these species are capable of performing time-compensated celestial navigation. Our clock-shift experiments suggest that a sun compass is involved. Individuals submitted to a 4h advance shift took significantly different mean orientations on release compared with control butterflies. The direction of this difference was consistent with the use of a sun compass. The magnitude was approximately half the predicted value if the vanishing bearing of released butterflies was used as the variable to evaluate the effect of time-shifting and approximately three-quarters of that predicted if the estimated heading was the variable used. Mean vanishing bearings of control and experimental butterflies did not correspond to predicted values, This difference can be attributed largely to the combined effects of wind and handling. C1 Univ Texas, Dept Zool, Austin, TX 78712 USA. Univ Oxford, Dept Zool, Oxford OX1 3PS, England. Smithsonian Trop Res Inst, Balboa, Panama. RP Oliveira, EG (reprint author), Univ Texas, Dept Zool, Austin, TX 78712 USA. NR 45 TC 29 Z9 34 U1 4 U2 9 PU COMPANY OF BIOLOGISTS LTD PI CAMBRIDGE PA BIDDER BUILDING CAMBRIDGE COMMERCIAL PARK COWLEY RD, CAMBRIDGE, CAMBS, ENGLAND CB4 4DL SN 0022-0949 J9 J EXP BIOL JI J. Exp. Biol. PD DEC PY 1998 VL 201 IS 24 BP 3317 EP 3331 PG 15 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 155WA UT WOS:000077968300005 ER PT J AU Graves, GR AF Graves, GR TI Stereotyped foraging behavior of the Swainson's warbler SO JOURNAL OF FIELD ORNITHOLOGY LA English DT Article AB I studied the foraging behavior of 399 individuals of Swainson's Warbler (Limnothlypis swainsonii) during the breeding season at more than 70 localities in the southeastern United States. Swainson's Warbler is a terrestrial dead-leaf specialist and "leaf-lifting" was the principal search/attack maneuver of all observed individuals. Pattering or vibration of feet is an important but previously unrecognized behavior associated with foraging in leaf litter. Observations indicate that leaf litter is a critical component of Swainson's Warbler habitat on breeding and winter territories and at migratory stopovers. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. RP Graves, GR (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. NR 26 TC 19 Z9 19 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0273-8570 J9 J FIELD ORNITHOL JI J. Field Ornithol. PD WIN PY 1998 VL 69 IS 1 BP 121 EP 127 PG 7 WC Ornithology SC Zoology GA YZ928 UT WOS:000072309000018 ER PT J AU Montali, RJ Bush, M Cromie, R Holland, SM Maslow, JN Worley, M Witebsky, FG Phillips, TM AF Montali, RJ Bush, M Cromie, R Holland, SM Maslow, JN Worley, M Witebsky, FG Phillips, TM TI Primary Mycobacterium avium complex infections correlate with lowered cellular immune reactivity in Matschie's tree kangaroos (Dendrolagus matschiei) SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article; Proceedings Paper CT Meeting of the American-Association-of-Zoo-Veterinarians CY 1995 CL E LANSING, MICHIGAN SP Amer Assoc Zoo Vet ID RESPONSES; AIDS; TUBERCULOSIS; STRESS; BLOOD; GAMMA; CELLS AB The National Zoological Park has maintained a breeding colony of Matschie's tree kangaroos (Dendrolagus matschiei) since 1975 with a documented history and continued prevalence of Mycobacterium avium complex (MAC) infections. No evidence of immunosuppressive retrovirus infections or loss of heterozygosity that may have led to an immune dysfunction in these animals was found. Isolates of MAC organisms from affected tree kangaroos and from their environment had no common restriction fragment DNA types. Cellular immune reactivity in apparently healthy tree kangaroos was 3- to 6-fold lower than in humans and other marsupial and eutherian mammals, as determined by lymphocyte proliferative assays. Thus, while MAC infections are typically opportunistic in humans and other mammals, tree kangaroos commonly develop primary progressive disease with MAC from random sources. Comparative information derived from this study should benefit both the endangered tree kangaroo and humans with immunosuppressive disorders that lead to mycobacterial infections. C1 Smithsonian Inst, Natl Zool Pk, Dept Pathol, Washington, DC 20008 USA. George Washington Univ, Med Ctr, Immunochem Lab, Washington, DC 20037 USA. Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Vet Serv, Front Royal, VA USA. NIAID, Host Def Lab, Bethesda, MD 20892 USA. NIH, Microbiol Serv, Dept Clin Pathol, Warren G Magnuson Clin Ctr, Bethesda, MD 20892 USA. VA Med Ctr, Dept Med, Boston, MA USA. San Diego Zoo, Ctr Reprod Endangered Species, San Diego, CA USA. RP Montali, RJ (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Pathol, 3001 Connecticut Ave NW, Washington, DC 20008 USA. NR 38 TC 21 Z9 21 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0022-1899 J9 J INFECT DIS JI J. Infect. Dis. PD DEC PY 1998 VL 178 IS 6 BP 1719 EP 1725 DI 10.1086/314517 PG 7 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 147AU UT WOS:000077466700024 PM 9815225 ER PT J AU Mair, RW Cory, DG Peled, S Tseng, CH Patz, S Walsworth, RL AF Mair, RW Cory, DG Peled, S Tseng, CH Patz, S Walsworth, RL TI Pulsed-field-gradient measurements of time-dependent gas diffusion SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE laser polarized noble gas; PGSE technique; gas diffusion; restricted diffusion; porous media ID NUCLEAR-MAGNETIC-RESONANCE; TO-VOLUME RATIO; NMR SPIN-ECHO; STIMULATED-ECHO; SELF-DIFFUSION; POROUS-MEDIA; SURFACE RELAXATION; XENON; XE-129; COEFFICIENT AB Pulsed-held-gradient NMR techniques are demonstrated for measurements of time-dependent gas diffusion. The standard PGSE technique and variants, applied to a free gas mixture of thermally polarized xenon and O-2, are found to provide a reproducible measure of the xenon diffusion coefficient (5.71 x 10(-6) m(2) s(-1) for 1 atm of pure xenon), in excellent agreement with previous, non-NMR measurements. The utility of pulsed-held-gradient NMR techniques is demonstrated by the first measurement of time-dependent (i.e., restricted) gas diffusion inside a porous medium (a random pack of glass beads), with results that agree well with theory. Two modified NMR pulse sequences derived from the PGSE technique (named the Pulsed Gradient Echo, or PGE, and the Pulsed Gradient Multiple Spin Echo, or PGMSE) are also applied to measurements of time dependent diffusion of laser polarized xenon gas, with results in good agreement with previous measurements on thermally polarized gas. The PGMSE technique is found to be superior to the PGE method, and to standard PGSE techniques and variants, for efficiently measuring laser polarized noble gas diffusion over a wide range of diffusion times, (C) 1998 Academic Press. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Brigham & Womens Hosp, Dept Radiol, Boston, MA 02115 USA. Harvard Univ, Sch Med, Boston, MA 02115 USA. RP Walsworth, RL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Patz, Samuel/I-2879-2012; Peled, Sharon/F-8590-2015 NR 51 TC 67 Z9 69 U1 0 U2 8 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD DEC PY 1998 VL 135 IS 2 BP 478 EP 486 DI 10.1006/jmre.1998.1588 PG 9 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 151MZ UT WOS:000077725400019 PM 9878475 ER PT J AU Neale, PJ Banaszak, AT Jarriel, CR AF Neale, PJ Banaszak, AT Jarriel, CR TI Ultraviolet sunscreens in Gymnodinium sanguineum (Dinophyceae): Mycosporine-like amino acids protect against inhibition of photosynthesis SO JOURNAL OF PHYCOLOGY LA English DT Article DE biological weighting function; dinoflagellate; fluorescence; photoinhibition; photoprotection; photosystem II; quantum yield ID BIOLOGICAL WEIGHTING FUNCTION; ANTARCTIC OZONE DEPLETION; UV-ABSORBING COMPOUNDS; GREAT-BARRIER-REEF; CHLOROPHYLL FLUORESCENCE; B RADIATION; ANTHOPLEURA-ELEGANTISSIMA; SPECTRAL IRRADIANCE; PROROCENTRUM-MICANS; SPECIES COMPOSITION AB Marine phytoplankton are sensitive to inhibition of photosynthesis by solar ultraviolet (UV) radiation, although sensitivity varies, depending on the growth environment. A mechanism suggested to increase resistance to UV inhibition is the accumulation of UV-absorbing compounds, such as the mycosporine-like amino acids (MAAs) found in many marine organisms. However, the effectiveness of these compounds as direct optical screens in microorganisms has remained unclear. The red-tide dinoflagellate Gymnodinium sanguineum Hirasaka accumulates about 14-fold more MAAs (per unit of chlorophyll) in high (76 W.m(-2)) than in low (15 W.m(-2)) growth irradiance. Biological weighting functions were estimated for UV inhibition of photosynthesis and showed that the high-light-grown cultures have lower sensitivity to UV radiation at wavelengths strongly absorbed by the MAAs. The time course of photosynthesis during exposure to UV radiation was measured using pulsed amplitude modulated (PAM) fluorometry and displayed a steady-state level after 15 min of exposure, indicating active repair of damage to the photosynthetic apparatus. Repair was blocked in the presence of the antibiotic streptomycin, yet high-light G. sanguineum remained less sensitive to UV radiation than did low-light cultures. These experiments show that MAAs act as spectrally specific UV/sunscreens in phytoplankton. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Neale, PJ (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. RI Neale, Patrick/A-3683-2012 NR 67 TC 164 Z9 172 U1 2 U2 13 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 DEC PY 1998 VL 34 IS 6 BP 928 EP 938 DI 10.1046/j.1529-8817.1998.340928.x PG 11 WC Plant Sciences; Marine & Freshwater Biology SC Plant Sciences; Marine & Freshwater Biology GA 155VB UT WOS:000077966100004 ER PT J AU Yoshino, K Huestis, DL Nicholls, RW AF Yoshino, K Huestis, DL Nicholls, RW TI Comment on the Herzberg continuum SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Letter ID I BANDS; OSCILLATOR-STRENGTHS; OXYGEN; O-2 C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. SRI Int, Mol Phys Lab, Menlo Park, CA 94025 USA. York Univ, Ctr Res Earth & Space Sci, N York, ON M3J 1P3, Canada. RP Yoshino, K (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 9 TC 2 Z9 2 U1 0 U2 3 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 DEC PY 1998 VL 60 IS 6 BP 1091 EP 1091 PG 1 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 139JH UT WOS:000077024700014 ER PT J AU Jordan, HL Howard, JG Bucci, JG Butterworth, JL English, R Kennedy-Stoskopf, S Tompkins, MB Tompkins, WA AF Jordan, HL Howard, JG Bucci, JG Butterworth, JL English, R Kennedy-Stoskopf, S Tompkins, MB Tompkins, WA TI Horizontal transmission of feline immunodeficiency virus with semen from seropositive cats SO JOURNAL OF REPRODUCTIVE IMMUNOLOGY LA English DT Article; Proceedings Paper CT Ares-Serono-Foundation Workshop on HIV-1 and Gametes CY OCT 14-17, 1997 CL SIENA, ITALY SP Ares Serono Fdn DE feline immunodeficiency virus; semen; artificial insemination; transmission ID DOMESTIC CATS; UNITED-STATES; ANIMAL-MODEL; INFECTION; AIDS; HIV-1; EJACULATE; MEN AB The AIDS virus of cat species, feline immunodeficiency virus (FIV), has been used extensively as an animal model of HIV-1 infection. This felid lentivirus shares many molecular and biochemical traits with HIV-1 and causes similar immunologic and clinical perturbations, most notably CD4(+) cell loss, impaired cell-mediated immunity and increased susceptibility to opportunistic pathogens. Previous reports have shown that FIV is transmitted horizontally by biting and vertically in utero and through nursing. Our objective was to determine whether FIV could be venereally transmitted in domestic cats. In the first experiment, susceptibility of the female reproductive tract to mucosal transmission of the FIV isolate, NCSU(1), was demonstrated via intravaginal inoculation with infected cultured cells. We next identified virus in electroejaculates from asymptomatic, chronically FIV-NCSU(1)-infected, adult males. A fragment of FIV gag provirus DNA was detected by nested polymerase chain reaction (PCR) in nonfractionated seminal cells and in swim-up sperm preparations. Additionally, replication-competent virus was isolated from cell-free seminal plasma and seminal cells by co-cultivation with a feline CD4+ T-cell line. In the third study, queens were artificially inseminated via an intrauterine laparoscopic technique with electroejaculates from FIV-NCSU(1)-infected males. Of six inseminations carried out with fresh semen, three resulted in infection of queens. Lastly, immunohistochemical studies identified potential virus target cell populations in normal female reproductive tissues. In conclusion, these experiments indicate that FIV infection in domestic cats may provide a unique small animal model of sexual transmission of HIV-I. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 Beth Israel Deaconess Med Ctr, Div Viral Pathogenesis, Boston, MA 02215 USA. Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. N Carolina State Univ, Coll Vet Med, Raleigh, NC 27606 USA. RP Jordan, HL (reprint author), Beth Israel Deaconess Med Ctr, Div Viral Pathogenesis, RE-113,330 Brookline Ave, Boston, MA 02215 USA. NR 43 TC 18 Z9 19 U1 2 U2 6 PU ELSEVIER IRELAND LTD PI CLARE PA ELSEVIER HOUSE, BROOKVALE PLAZA, EAST PARK SHANNON, CO, CLARE, 00000, IRELAND SN 0165-0378 J9 J REPROD IMMUNOL JI J. Reprod. Immunol. PD DEC PY 1998 VL 41 IS 1-2 BP 341 EP 357 PG 17 WC Immunology; Reproductive Biology SC Immunology; Reproductive Biology GA 155KQ UT WOS:000077946200027 PM 10213322 ER PT J AU Rouse, RC Dunn, PJ Peacor, DR Wang, LP AF Rouse, RC Dunn, PJ Peacor, DR Wang, LP TI Structural studies of the natural antimonian pyrochlores - I. Mixed valency, cation site splitting, and symmetry reduction in lewisite SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID DEFECT PYROCHLORES; NEUTRON-DIFFRACTION; ELECTRICAL-PROPERTIES; CRYSTAL-STRUCTURE; OXYGEN VACANCIES AB A type sample of the natural pyrochlore-group mineral lewisite, (Ca,Mn(2+),Na)(1.12)Sb(0.65)(3+)(Sb(5+),Ti(4+),Fe(3+),Al is cubic, F (4) over bar 3m (pseudo-Fd (3) over bar m), with a 10.277(1) Angstrom and Z = 8. The structure has been solved and refined in Fd (3) over bar m (R = 0.017), F (4) over bar 3m (R = 0.014), and F23 (R = 0.014) using 218 (or 326) X-ray reflections [I(obs)>2 sigma(I)] from a four-circle diffractometer and compositional constraints from electron microprobe and infrared spectroscopic analyses. Antimony is present in two valence states (Sb(5+):Sb(3+) = 60:40), with Sb(5+) ordered in the pyrochlore B site (16c in Fd (3) over bar m). To accommodate the different coordination requirements of Sb(3+) (a lone-pair ion) and Ca(2+), the pyrochlore A site is split into 8-coordinated Ca(2+) on A(16d) and Sb(3+) on an asymmetrically 5-coordinated site, A'(96g), the A-A' separation being ca. 0.5 Angstrom, The deviation from Fd (3) over bar m symmetry is small, as shown by the fact that only two of the symmetry-forbidden reflections (200 and 420) have statistically significant intensities. The finding of F4 (3) over bar m symmetry in lewisite supports the choice of this space group for certain anomalous synthetic pyrochlores that have been characterized by powder diffraction methods. A previous study that purports to discredit lewisite as a two-phase mixture is shown to be in error. (C) 1998 Academic Press. C1 Univ Michigan, Dept Geol Sci, Ann Arbor, MI 48109 USA. Smithsonian Inst, Dept Mineral Sci, Washington, DC 20560 USA. RP Rouse, RC (reprint author), Univ Michigan, Dept Geol Sci, 1006 CC Little Bldg, Ann Arbor, MI 48109 USA. NR 38 TC 15 Z9 15 U1 1 U2 9 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD DEC PY 1998 VL 141 IS 2 BP 562 EP 569 DI 10.1006/jssc.1998.8019 PG 8 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 153MP UT WOS:000077837100033 ER PT J AU Bourguet, D Fonseca, D Vourch, G Dubois, MP Chandre, F Severini, C Raymond, M AF Bourguet, D Fonseca, D Vourch, G Dubois, MP Chandre, F Severini, C Raymond, M TI The acetylcholinesterase gene Ace: A diagnostic marker for the Pipiens and Quinquefasciatus forms of the Culex pipiens complex SO JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION LA English DT Article DE acetylcholinesterase gene; Culex pipiens complex; diagnostic marker; sibling species; Culex torrentium; Culex pipiens "molestus" ID POLYMERASE CHAIN-REACTION; INSECTICIDE RESISTANCE; INSENSITIVE ACETYLCHOLINESTERASE; DETOXIFYING ESTERASES; NEOTYPE DESIGNATION; SAY DIPTERA; CULICIDAE; MOSQUITOS; AMPLIFICATION; MECHANISMS AB The taxonomy of the Culex pipiens complex remains a controversial issue in mosquito systematics. Based on morphologic characters, 2 allopatric taxa are recognized, namely Cx. pipiens (including the form "molestus") in temperate areas and Cx. quinquefasciatus in tropical areas. Here we report on variability at the nucleotide level of an acetylcholinesterase gene in several strains and natural populations of this species complex. Few polymorphisms were found in coding regions within a subspecies but many polymorphisms were observed between subspecies in noncoding regions. We describe a method based on a restriction enzyme polymorphism in polymerase chain reaction-amplified DNA, in which the presence or absence of one restriction site discriminates Cx. pipiens, Cx. quinquefasciatus, and their hybrids. This technique reliably discriminates mosquitoes from more than 30 worldwide strains or populations. Polymerase chain reaction amplification of specific alleles may also be a useful tool for characterizing specific alleles of each sibling taxon. C1 Smithsonian Inst, Natl Zool Pk, Mol Genet Lab, DZR, Washington, DC 20008 USA. ORSTOM, Lab Lutte Insectes Nuisibles, F-34032 Montpellier, France. Ist Super Sanita, Lab Parassitol, I-00161 Rome, Italy. Univ Montpellier 2, Inst Sci Evolut, UMR 5554, Lab Genet & Environm, F-34090 Montpellier, France. RP Raymond, M (reprint author), Univ Montpellier 2, Inst Sci Evolut, UMR 5554, Lab Genet & Environm, Pl Eugene Bataillon, F-34090 Montpellier, France. RI Raymond, Michel/C-9049-2015; OI Raymond, Michel/0000-0002-1714-6984; Fonseca, Dina/0000-0003-4726-7100 NR 45 TC 38 Z9 41 U1 0 U2 4 PU AMER MOSQUITO CONTROL ASSN INC PI LAKE CHARLES PA 2200 E PRIEN LAKE RD, LAKE CHARLES, LA 70601 USA SN 8756-971X J9 J AM MOSQUITO CONTR JI J. Am. Mosq. Control Assoc. PD DEC PY 1998 VL 14 IS 4 BP 390 EP 396 PG 7 WC Entomology SC Entomology GA 174BE UT WOS:000079013600007 PM 10084132 ER PT J AU Kaeppler, AL AF Kaeppler, AL TI In oceania: Visions, artifacts, histories. 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 DEC PY 1998 VL 107 IS 4 BP 432 EP 433 PG 2 WC Anthropology SC Anthropology GA 264HD UT WOS:000084174000016 ER PT J AU Piperno, DR AF Piperno, DR TI Paleoethnobotany in the Neotropics from microfossils: New insights into ancient plant use and agricultural origins in the tropical forest SO JOURNAL OF WORLD PREHISTORY LA English DT Review DE paleoethnobotany; Neotropics; phytoliths; pollen; starch grains ID DIAGNOSTIC OPAL PHYTOLITHS; ORYZA-SATIVA POACEAE; REPRODUCTIVE STRUCTURES; MAIZE CULTIVATION; POLLEN RECORD; PANAMA; VEGETATION; HOLOCENE; AMAZON; OCCUPATION C1 Smithsonian Tropical Res Inst, Balboa, Panama. RP Piperno, DR (reprint author), Smithsonian Tropical Res Inst, Box 2072, Balboa, Panama. NR 139 TC 26 Z9 27 U1 1 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0892-7537 J9 J WORLD PREHIST JI J. World Prehist. PD DEC PY 1998 VL 12 IS 4 BP 393 EP 449 DI 10.1023/A:1022812132194 PG 57 WC Anthropology; Archaeology SC Anthropology; Archaeology GA 224KR UT WOS:000081898700001 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI Wondrous strange: The Wyeth tradition. 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 DEC PY 1998 VL 123 IS 20 BP 100 EP 100 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 148BH UT WOS:000077532000065 ER PT J AU Bijma, J Hemleben, C Huber, BT Erlenkeuser, H Kroon, D AF Bijma, J Hemleben, C Huber, BT Erlenkeuser, H Kroon, D TI Experimental determination of the ontogenetic stable isotope variability in two morphotypes of Globigerinella siphonifera (d'Orbigny) SO MARINE MICROPALEONTOLOGY LA English DT Article DE planktic foraminifera; biology; stable isotope fractionation; ontogeny ID LIVING PLANKTONIC-FORAMINIFERA; BIOLOGICAL CARBONATES; FRACTIONATION; OXYGEN; PHOTOSYNTHESIS; SEDIMENT; CALCITE; OCEAN; TESTS; C-13 AB Carbon and oxygen isotope fractionation in two morphotypes (Type I and Type II) of the symbiont bearing planktic foraminifer Globigerinella siphonifera (d'Orbigny) is investigated. SCUBA collected specimens were grown in the laboratory under identical culture conditions and their stable isotope signature was analyzed to characterize the influence of ontogeny and feeding rate on their delta(13)C and delta(18)O signals. The two types show a positive linear correlation between delta(13)C and delta(18)O With size. Type LT is enriched in C-13 and O-18 relative to Type I and the enrichment per size increment is greater than for Type I. The carbon isotope composition of Type I tends towards lighter values at higher feeding rates whereas Type II is unaffected by the feeding regime. In order to determine if the isotopic response can be attributed to differences in growth characteristics and/or host/symbiont interactions, specimens were cultured under a variety of conditions and the pigment composition of freshly collected specimens was measured. Type I has a much lower photo-pigment content, which probably implies a lower gross photosynthetic rate. In addition, its growth and calcification rate are lower. The impact of these life processes on the stable isotope composition is discussed and it is argued that isotope fractionation is controlled by two linked processes. The carbon isotope fractionation is affected directly by a C-12 depletion or enrichment of the microenvironment via symbiont photosynthesis and host respiration, respectively. Concurrently, the life processes invoke a kinetic fractionation of the carbon and oxygen isotopes via their impact on the ambient carbonate chemistry. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Tubingen, Inst & Museum Geol & Palaontol, D-72076 Tubingen, Germany. Natl Museum Nat Hist, Dept Paleobiol, Smithsonian Inst, Washington, DC 20560 USA. Univ Kiel, Inst Reine & Angew Kernphys, Lab C14, D-24118 Kiel, Germany. Univ Edinburgh, Grant Inst Geol, Dept Geol & Geophys, Edinburgh EH9 3JW, Midlothian, Scotland. Alfred Wegener Inst Polar & Meeresforsch, D-27568 Bremerhaven, Germany. RP Bijma, J (reprint author), Univ Bremen, Fachbereich Geowissensch, Klagenfurter Str, D-28359 Bremen, Germany. OI Bijma, Jelle/0000-0003-4371-1438 NR 59 TC 43 Z9 43 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-8398 J9 MAR MICROPALEONTOL JI Mar. Micropaleontol. PD DEC PY 1998 VL 35 IS 3-4 BP 141 EP 160 DI 10.1016/S0377-8398(98)00017-6 PG 20 WC Paleontology SC Paleontology GA 156KM UT WOS:000078000200001 ER PT J AU Wilf, P Beard, KC Davies-Vollum, KS Norejko, JW AF Wilf, P Beard, KC Davies-Vollum, KS Norejko, JW TI Portrait of a late paleocene (early Clarkforkian) terrestrial ecosystem: Big Multi Quarry and associated strata, Washakie Basin, Southwestern Wyoming SO PALAIOS LA English DT Article ID CLARKS-FORK-BASIN; EARLY EOCENE; VEGETATIVE MORPHOLOGY; BIGHORN BASIN; PALEOECOLOGY; PALEOSOLS; PHYLOGENY; CLIMATES; PRIMATE; USA AB In-depth understanding of past climatic and biotic change requires the study of ancient ecosystems. However, terrestrial plants and vertebrates are preferentially preserved under very different taphonomic conditions, and diverse fossil floras and faunas are rarely found in close association. Big Multi Quarry and associated strata in the uppermost Fort Union Formation of the Washakie Basin, southwestern Wyoming, provide a uniquely detailed record of terrestrial fauna, flora, and climate during the early Clarkforkian. The Clarkforkian Land Mammal Age, approximately the last million years of the Paleocene, wars an interval of global warming that had profound biotic consequences. The mammalian fauna of Big Multi Quarry, consisting of 41 species, is the most diverse known from a single Clarkforkian locality. Unlike most other Clarkforkian faunas, this assemblage is not significantly biased against small forms. Lipotyphlan insectivores were dominant, and arboreally adapted taxa were abundant and diverse. The closely associated and well-preserved fossil plant assemblage was overwhelmingly dominated by a single species belonging to the birch family. Floral richness, heterogeneity, and evenness were as low as in the Tiffanian of the same region, showing that forest structure remained monotonous even as climate warned and mammals diversified in the Clarkforkian. The plant assemblage more closely resembles middle than early Clarkforkian floras of northern Wyoming, suggesting northward migration, of the ranges of plant taxa coincident with warming. A great deal of research has focused on the unusually warm interiors of continents in the terminal Paleocene and early Eocene. Multiple lines of evidence from our study, including sedimentological indicators, analyses of the nearest living relatives and functional analogues of the fossil plants and animals, size and margin analysis of fossil leaves, and cenogram analysis of the mammalian fauna, indicate that southwestern Wyoming had a humid subtropical climate with little or no seasonal frost or marked dry season, well before the terminal Paleocene. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. Carnegie Mellon Univ, Sect Vertebrate Paleontol, Pittsburgh, PA 15213 USA. Ball State Univ, Dept Geol, Muncie, IN 47306 USA. SUNY Stony Brook, Dept Anat Sci, Stony Brook, NY 11794 USA. RP Wilf, P (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, MRC 121, Washington, DC 20560 USA. OI Beard, K. Christopher/0000-0002-6279-9837; Wilf, Peter/0000-0001-6813-1937 NR 103 TC 30 Z9 34 U1 0 U2 4 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 6128 EAST 38TH ST, STE 308, TULSA, OK 74135-5814 USA SN 0883-1351 J9 PALAIOS JI Palaios PD DEC PY 1998 VL 13 IS 6 BP 514 EP 532 DI 10.2307/3515344 PG 19 WC Geology; Paleontology SC Geology; Paleontology GA 143DQ UT WOS:000077240100002 ER PT J AU Marinescu, M Vrinceanu, D Sadeghpour, HR AF Marinescu, M Vrinceanu, D Sadeghpour, HR TI Radiative transitions and van der Waals coefficients for francium SO PHYSICAL REVIEW A LA English DT Article ID ATOMS; SPECTROSCOPY; TRAP AB Francium has been the least-studied alkali-metal atom until recently. We present accurate calculations for the discrete and continuum optical transitions, and dispersion coefficients for two colliding francium atoms. Spinorbit coupling is explicitly included and the influence of core polarization on the energies and the electric dipole operator is considered. Predictions for a range of transition amplitudes that are needed for parity violation experiments are made. The van der Waals coefficients for the long-range collision of two-groundstate Fr atoms in different fine-structure levels show a departure from an established trend in other alkali-metal atoms. We comment on the differences. [S1050-2947(98)50312-5]. C1 Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Marinescu, M (reprint author), Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. EM hsadeghpour@cfa.harvard.edu NR 26 TC 11 Z9 11 U1 0 U2 1 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 DEC PY 1998 VL 58 IS 6 BP R4259 EP R4262 DI 10.1103/PhysRevA.58.R4259 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 145CD UT WOS:000077352700001 ER PT J AU Schimming, T Tofern, B Mann, P Richer, A Jenett-Siems, K Drager, B Asano, N Gupta, MP Correa, MD Eich, E AF Schimming, T Tofern, B Mann, P Richer, A Jenett-Siems, K Drager, B Asano, N Gupta, MP Correa, MD Eich, E TI Distribution and taxonomic significance of calystegines in the convolvulaceae SO PHYTOCHEMISTRY LA English DT Article DE Aniseia; Argyreia; Bonamia; Calystegia; Convolvulus; Cuscuta; Dichondra; Erycibe; Evolvulus; Falkia; Hewittia; Ipomoea; Iseia; Jacquemontia; Lepistemon; Maripa; Merremia; Odonellia; Operculina; Porana; Stictocardia; Turbina; Convolvulaceae; GC-MS; tropane alkaloids; calystegines; glycosidase inhibitors; chemotaxonomy ID GLYCOSIDASE INHIBITORY ACTIVITIES; TROPANE ALKALOIDS; IDENTIFICATION; SOLANACEAE; TOXICITY; SUGARS; SEPIUM AB The GC-MS analysis of 65 convolvulaceous species from many, predominantly tropical provenances, belonging to 22 genera (9 tribes), revealed the occurrence of one to five calystegines in 30 species belonging to 15 genera (8 tribes). This indicates the chemotaxonomic significance of these glycosidase inhibiting polyhydroxy-nortropanes for the Convolvulaceae. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Free Univ Berlin, Inst Pharm Pharmazeut Biol 2, D-14195 Berlin, Germany. Univ Halle Wittenberg, Inst Pharmazeut Biol, D-06120 Halle, Germany. Hokuriku Univ, Fac Pharmaceut Sci, Kanazawa, Ishikawa 92011, Japan. Univ Panama, Fac Farm, Ctr Invest Farmacognost Flora Panamena, CIFLORPAN, Panama City, Panama. Univ Panama, Smithsonian Trop Res Inst, Herbarium, Panama City, Panama. RP Eich, E (reprint author), Free Univ Berlin, Inst Pharm Pharmazeut Biol 2, Konigin Luise Str 2 4, D-14195 Berlin, Germany. OI Gupta, Mahabir/0000-0002-9302-7864 NR 28 TC 32 Z9 33 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0031-9422 J9 PHYTOCHEMISTRY JI Phytochemistry PD DEC PY 1998 VL 49 IS 7 BP 1989 EP 1995 DI 10.1016/S0031-9422(98)00430-0 PG 7 WC Biochemistry & Molecular Biology; Plant Sciences SC Biochemistry & Molecular Biology; Plant Sciences GA 150AT UT WOS:000077640800023 ER PT J AU Koranyi, DM Kleyna, J Grogin, NA AF Koranyi, DM Kleyna, J Grogin, NA TI Self-consistent photometric calibration of a mosaic survey with overlaps SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article AB We describe a robust and computationally efficient technique for arriving at a set of self-consistent zero points for a set of overlapping photometric and nonphotometric images. This method allows the calibration of an entire survey from only a few photometric frames or at least the determination of mutually self-consistent zero points in the absence of any photometric reference. 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. NR 1 TC 5 Z9 5 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 DEC PY 1998 VL 110 IS 754 BP 1464 EP 1466 DI 10.1086/316284 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 150JA UT WOS:000077660400012 ER PT J AU Iafolla, V Nozzoli, S Lorenzini, EC Milyukov, V AF Iafolla, V Nozzoli, S Lorenzini, EC Milyukov, V TI Methodology and instrumentation for testing the weak equivalence principle in stratospheric free fall SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID LUNAR AB The use of the GiZero free-fall facility for testing the weak equivalence principle is discussed in this article. GiZero consists of a vacuum capsule, released from a balloon at an altitude of 40 km, which shields an experimental apparatus free falling inside the capsule itself. The expected residual acceleration external to the detector is 10(-12) g (with g the Earth's gravitational acceleration) for the 30 s free fall. A common-mode rejection factor of about 10(-4) reduces the residual noise differential output to only 10(-16) g. The gravity detector is a differential accelerometer with two test masses with coincident center of masses (i.e., zero baseline) with capacitive pick ups. Preparatory experiments have been conducted in the laboratory with a precursor detector by measuring controlled gravity signals, at low frequency, and by observing the Luni-Solar tides. The estimated accuracy in testing the weak equivalence principle, with a 95% confidence level, is 5 x 10(-15) in a 30 s free fall. When compared to orbital free-fall experiments, the GiZero experiment can be considered as a valid compromise which is able to satisfy the requirement for improving significantly the experimental accuracy in testing the equivalence principle with a substantial lower cost, the ability to recover the detector and to repeat the experiment at relatively short time intervals. (C) 1998 American Institute of Physics. [S0034-6748(98)00412-2]. C1 CNR, Ist Fis Spazio Interplanetario, I-00133 Rome, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Moscow MV Lomonosov State Univ, Sternberg Astron Inst, Moscow 119899, Russia. RP CNR, Ist Fis Spazio Interplanetario, I-00133 Rome, Italy. OI Iafolla, Valerio Antonio/0000-0001-5297-1157 NR 24 TC 16 Z9 17 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0034-6748 EI 1089-7623 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD DEC PY 1998 VL 69 IS 12 BP 4146 EP 4151 DI 10.1063/1.1149261 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 144BP UT WOS:000077293600019 ER PT J AU Guzman, HM Guevara, CA AF Guzman, HM Guevara, CA TI Coral reefs of Bocas del Toro, Panama: II. Reef distribution, structure and conservation condition in Bastimentos, Solarte, Carenero and Colon islands SO REVISTA DE BIOLOGIA TROPICAL LA Spanish DT Article DE coral reefs; Caribbean; biodiversity; protected area; ecology; reef assessment ID SCLERACTINIAN CORALS; CAYOS-COCHINOS; PATCH REEFS; WEST-INDIES; COSTA-RICA; PATTERNS; EUTROPHICATION; ABUNDANCE; SEDIMENTATION; HONDURAS AB The distribution and conservation status of coral reefs along the northern section of the archipelago of Bocas del Toro are evaluated (ca. 120 km), and the structure of 18 reefs around the islands of Bastimentos, Solarte, Carenero and Colon is described. Reef habitats located on the seaward side (exposed) of the islands exhibited the lowest coral cover (8%) and coral diversity, while leeward reefs (protected) showed the highest living coral cover (32%) and diversity. Macroalgae coverage was similar in both habitats but high (50%) if compared with other continental reefs described in the Ensenada Grande of Almirante Bay (4%). A total of 54 coral species was recorded, representing a 35% increase from previous studies for the region and 88% of the total species described for Panama. The diversity of reefs, reef organisms and habitats in the archipelago was greater outside the national park of Isla Bastimentos, the only marine protected area in western Panama. Some recommendations are provided for an integrated management of marine-terrestrial natural resources in the region, in particular, a complete change on the existing limits of the protected area and the creation of new reserves. C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Guzman, HM (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 45 TC 15 Z9 16 U1 1 U2 9 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 DEC PY 1998 VL 46 IS 4 BP 889 EP 912 PG 24 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 256CJ UT WOS:000083708100002 ER PT J AU Grajales, GG Wcislo, W AF Grajales, GG Wcislo, W TI Nest architecture of group-living wasps Microstigmus (Hymenoptera : Sphecidae): role of the pedicel as a defense against ants SO REVISTA DE BIOLOGIA TROPICAL LA English DT Article DE brood predation; ants; nest architecture; maternal care; defense ID LATITUDINAL GRADIENT AB The nest pedicel of a social sphecid wasp Microstigmus nr. thripoctenus plays an important role in protecting the brood against ant predators, as inferred from data on artificial nests. a pair of artificial nests with or without pedicels was suspended from the undersides of leaves (Carludovica palmata) for 30 min to assess rates of discovery and removal of food (tuna bait) by ants (N = 36 pairs). Three-hundred and forty-three individuals of five ant species removed food at a higher frequency from;nests without pedicels (83.3.% of 36 nests) than from nests with pedicels (11.1% of 36 nests). C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Grajales, GG (reprint author), Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. NR 11 TC 2 Z9 2 U1 0 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 DEC PY 1998 VL 46 IS 4 BP 1141 EP 1143 PG 3 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 256CJ UT WOS:000083708100023 ER PT J AU Eberhard, JR AF Eberhard, JR TI Breeding biology of the Monk Parakeet SO WILSON BULLETIN LA English DT Article ID BEHAVIOR; PARROTLET AB The Monk Parakeet (Myiopsitta monachus) is unique among parrots because it constructs stick nests rather than nesting in holes. This study provides a detailed description of the species' breeding biology and provides evidence that this species might breed cooperatively. Although many parakeet pairs were observed roosting in solitary nests, breeding occurred only in nests within colonies or chambers within compound nests housing other parakeets. The male was responsible for all or most of the nest construction and maintenance. He fed the female during the incubation and early nestling periods, but later in the nestling period both the male and female fed the nestlings. Most breeding attempts involved a male-female pair, but three separate breeding attempts were made by trios (two trios included a female and two males, and the third trio was composed of a male and two females). In the trios, one of the auxiliary bird contributed less to the breeding effort than the primary male and female. The observations of trios support the idea that Monk Parakeets are similar to cooperative breeders, but the lack of cooperation in nest building indicates that colonial nesting may be a result of other benefits of group living, such as improved predator detection. C1 Princeton Univ, Dept Ecol & Evolutionary Biol, Princeton, NJ 08544 USA. RP Eberhard, JR (reprint author), Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. NR 31 TC 34 Z9 39 U1 2 U2 15 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 DEC PY 1998 VL 110 IS 4 BP 463 EP 473 PG 11 WC Ornithology SC Zoology GA 152GN UT WOS:000077768400002 ER PT J AU McLaughlin, BM Kirby, KP AF McLaughlin, BM Kirby, KP TI Photoabsorption of atomic oxygen in the vicinity of the K-edge SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID OPEN-SHELL ATOMS; ELECTRON COLLISIONAL EXCITATION; O-II; INTERMULTIPLET 1S(2)2S(2)2P(3); FORBIDDEN TRANSITIONS; AUGER SPECTRUM; PHOTOIONIZATION; SPECTROMETRY; 1S(2)2S2P(4); SCATTERING AB Ab initio cross section calculations using the R-matrix approach have been performed for the inner-shell photoabsorption of atomic oxygen in the photon energy region 520-555 eV. The prominent O*(1s2s(2)2p(4)(P-2.4(c))np P-3(o)) resonance series, converging to the (2.4)p(c) series limit of atomic oxygen, dominate the cross section in the vicinity of the K-edge. A comparison of the calculations with two recent sets of experimental measurements taken at the Advanced Light Source and at the Wisconsin synchrotron facility is made. C1 Queens Univ Belfast, Dept Appl Math & Theoret Phys, Belfast BT7 1NN, Antrim, North Ireland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP McLaughlin, BM (reprint author), Queens Univ Belfast, Dept Appl Math & Theoret Phys, Belfast BT7 1NN, Antrim, North Ireland. NR 36 TC 34 Z9 34 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD NOV 28 PY 1998 VL 31 IS 22 BP 4991 EP 5002 DI 10.1088/0953-4075/31/22/010 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 146LQ UT WOS:000077430900010 ER PT J AU Baldwin, CC Smith, WL AF Baldwin, CC Smith, WL TI Belonoperca pylei, a new species of seabass (Teleostei : Serranidae : Epinephelinae : Diploprionini) from the Cook Islands with comments on relationships among diploprionins SO ICHTHYOLOGICAL RESEARCH LA English DT Article DE Serranidae; Belonoperca; Cook Islands; phylogeny; larval morphology AB Belonoperca pylei is described from five specimens collected at depths of 68-122 m from Rarotonga, Cook Islands. It differs from all other known diploprionin serranids in having IX, 10 dorsal-fin rays, III, 7 anal-fin rays, and a color pattern composed primarily of yellow and orange pigments. Cladistic analysis of epinepheline morphology supports monophyly of the diploprionin genera Belonoperca and Diploprion and suggests that Belonoperca is the sister group of Diploprion plus the monotypic Aulacocephalus. C1 Smithsonian Inst, Natl Museum Nat Hist, Div Fishes, Washington, DC 20560 USA. RP Baldwin, CC (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Div Fishes, MRC 159, Washington, DC 20560 USA. NR 18 TC 3 Z9 4 U1 0 U2 2 PU ICHTHYOLOGICAL SOC JAPAN PI TOKYO PA BUSINESS CENTER ACADEMIC SOC JAPAN, 5-16-9 HONKOMAGOME, BUNKYO-KU, TOKYO, 113, JAPAN SN 1341-8998 J9 ICHTHYOL RES JI Ichthyol. Res. PD NOV 26 PY 1998 VL 45 IS 4 BP 325 EP 339 DI 10.1007/BF02725185 PG 15 WC Zoology SC Zoology GA 160ZX UT WOS:000078264200001 ER PT J AU Guainazzi, M Nicastro, F Fiore, F Matt, G McHardy, I Orr, A Barr, P Fruscione, A Papadakis, I Parmar, AN Uttley, P Perola, GC Piro, L AF Guainazzi, M Nicastro, F Fiore, F Matt, G McHardy, I Orr, A Barr, P Fruscione, A Papadakis, I Parmar, AN Uttley, P Perola, GC Piro, L TI A swan song: the disappearance of the nucleus of NGC 4051 and the echo of its past glory SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Letter DE galaxies : individual : NGC 4051; galaxies : Seyfert; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; X-RAY REFLECTION; COLD MATTER; SPECTRAL VARIABILITY; SEYFERT-1 GALAXIES; ASCA OBSERVATIONS; IRON LINE; NGC-1068; EMISSION; NGC-4051 AB On 1998 May 9-11,BeppoSAX observed the low-luminosity Seyfert 1 galaxy NGC 4051 in an ultra-dim X-ray state. The 2-10 keV flux (1.26 x 10-(12) erg cm(-2) s(-1)) was about 20 times fainter than its historical average value, and remained steady along the whole observation (similar to 2.3 d). The observed flat spectrum (Gamma similar or equal to 0.8) and intense iron line (EW similar or equal to 600 eV) are best explained by assuming that the active nucleus has switched off, leaving only a residual reflection component visible. C1 European Space Agcy, Estec, Dept Space Sci, Div Astrophys, NL-2200 AG Noordwijk, Netherlands. CNR, Ist Astrofis Spaziale, I-00133 Rome, Italy. Osservatorio Astron Roma, I-00040 Monte Porzio Catone, Italy. BeppoSAX Sci Data Ctr, I-00131 Rome, Italy. Univ Roma 3, Dipartimento fis E Amaldi, I-00146 Rome, Italy. Univ Southampton, Dept Phys & Astron, Southampton SO17 1BJ, Hants, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Crete, Dept Phys, Skinakas Observ, Heraklion, Crete, Greece. RP Guainazzi, M (reprint author), European Space Agcy, Estec, Dept Space Sci, Div Astrophys, Postbus 299, NL-2200 AG Noordwijk, Netherlands. RI Papadakis, Iossif/C-3235-2011; PIRO, LUIGI/E-4954-2013 OI PIRO, LUIGI/0000-0003-4159-3984 NR 39 TC 77 Z9 77 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 NOV 21 PY 1998 VL 301 IS 1 BP L1 EP L4 DI 10.1046/j.1365-8711.1998.02089.x PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 147MB UT WOS:000077570600001 ER PT J AU Zygelman, B Stancil, PC Dalgarno, A AF Zygelman, B Stancil, PC Dalgarno, A TI Stimulated radiative association of He and H+ SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic processes; early universe; molecular processes; planetary nebulae : general; quasars : general ID AB-INITIO; EMISSION AB The enhancement of the rate coefficient for the radiative association of He and H+ to form HeH+ arising from stimulated emission due to a blackbody radiation held is calculated. The effects on the fractional abundance of HeH+ in the early universe, in supernova ejecta, and in planetary nebulae are small. There may occur some enhancement in the abundance of HeH+ in quasar broad-line clouds. C1 Univ Nevada, Dept Phys, WM Keck Lab Computat Phys, Las Vegas, NV 89154 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Zygelman, B (reprint author), Univ Nevada, Dept Phys, WM Keck Lab Computat Phys, Las Vegas, NV 89154 USA. NR 21 TC 44 Z9 44 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 NOV 20 PY 1998 VL 508 IS 1 BP 151 EP 156 DI 10.1086/306399 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LX UT WOS:000077780000012 ER PT J AU Herrnstein, JR Moran, JM Greenhill, LJ Blackman, EG Diamond, PJ AF Herrnstein, JR Moran, JM Greenhill, LJ Blackman, EG Diamond, PJ TI Polarimetric observations of the masers in NGC 4258: An upper limit on the large-scale magnetic field 0.2 Parsecs from the central engine SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; galaxies : individual (NGC 4258); galaxies : magnetic fields; galaxies : nuclei; masers; polarization ID ACTIVE GALACTIC NUCLEI; ADVECTION-DOMINATED ACCRETION; ASTROPHYSICAL MASERS; GALAXY NGC-4258; MOLECULAR DISK; WATER MASERS; BLACK-HOLES; EMISSION; POLARIZATION; RADIATION AB report VLA 1 sigma upper limits of 1.5% and 3% on the intrinsic circular and linear fractional polarizations, respectively, of the water vapor maser emission 0.2 pc from the central engine of NGC 4258. A corresponding 0.5% upper limit on any Zeeman-splitting-induced circular polarization translates to a 1 sigma upper limit on the parallel, or toroidal, component of the magnetic field of 300 mG. Assuming magnetic and thermal pressure balance in the disk, this magnetic field upper limit corresponds to a model-dependent estimate of the accretion rate through the molecular disk of 10(-1.9) alpha M-. yr(-1) for the case where the magnetic field lies along the line of sight. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Natl Radio Astron Observ, Socorro, NM 87801 USA. RP Herrnstein, JR (reprint author), Natl Radio Astron Observ, POB O, Socorro, NM 87801 USA. NR 36 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 NOV 20 PY 1998 VL 508 IS 1 BP 243 EP 247 DI 10.1086/306398 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LX UT WOS:000077780000018 ER PT J AU Bell, MB Watson, JKG Feldman, PA Travers, MJ AF Bell, MB Watson, JKG Feldman, PA Travers, MJ TI The excitation temperatures of HC9N and other long cyanopolyynes in TMC-1 SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (Taurus Molecular Cloud); ISM : molecules; molecular data; molecular processes; radio lines : ISM ID DENSE INTERSTELLAR CLOUDS; GAS-PHASE PRODUCTION; COMPLEX-MOLECULES; DARK CLOUDS; TAURUS; CHEMISTRY; CARBON; MODEL; CHAIN; HC3N AB We report observations of seven different transitions of HC9N between 9.8 and 23.3 GHz in the cold, dark cloud TMC-1. Because of its lower rotational constant, HC9N is expected to yield a rotational temperature closer to the kinetic temperature of the gas than the shorter cyanopolyynes. Assuming that HC9N in TMC-1 is optically thin, we obtain a rotational temperature T-rot = 7.5-8.7 K and a corresponding column density of N-L(HC9N) = (5.4-2.3) x 10(12) cm(-2), depending on the source size L assumed. The rate of radiative cooling is less efficient in the longer cyanopolyyne chains and is approximately proportional to (n + 1)(-6), where n is the number of carbon atoms in the chain. In steady state this is balanced by the collisional rate of excitation. The rotational temperatures of the cyanopolyynes are found to increase with the number of heavy atoms over the range HC5N-HC9N, in reasonable agreement with calculations. Concomitantly, we find evidence that the longer cyanopolyynes are located in regions that become progressively smaller with chain length. We also report newly measured values for the rotational and centrifugal distortion constants of HC9N that improve the accuracy of the calculated millimeter wave transitions. C1 Natl Res Council Canada, Herzberg Inst Astrophys, Ottawa, ON K1A 0R6, Canada. Natl Res Council Canada, Steacie Inst Mol Sci, Ottawa, ON K1A 0R6, Canada. Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC V8X 4M6, Canada. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Bell, MB (reprint author), Natl Res Council Canada, Herzberg Inst Astrophys, 100 Sussex Dr, Ottawa, ON K1A 0R6, Canada. NR 23 TC 24 Z9 24 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 NOV 20 PY 1998 VL 508 IS 1 BP 286 EP 290 DI 10.1086/306405 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LX UT WOS:000077780000023 ER PT J AU Vanhala, HAT Cameron, AGW AF Vanhala, HAT Cameron, AGW TI Numerical simulations of triggered star formation. I. Collapse of dense molecular cloud cores SO ASTROPHYSICAL JOURNAL LA English DT Review DE hydrodynamics; ISM : clouds; shock waves; solar system : formation; stars : formation ID HERBIG-HARO OBJECTS; SMOOTHED PARTICLE HYDRODYNAMICS; YOUNG STELLAR OBJECTS; INTERSTELLAR CLOUDS; ORION-NEBULA; SOLAR NEBULA; SHOCK-WAVES; GAMMA-RAYS; GUM NEBULA; GAS CLOUDS AB Results from numerical simulations of shock waves impacting molecular cloud cores are presented. The three-dimensional smoothed particle hydrodynamics code used in the calculations includes effects from a varying adiabatic exponent, molecular, atomic, and dust cooling, as well as magnetic pseudofluid. The molecular cloud cores are assumed to be embedded in background cloud material and to have evolved into their preimpact state under ambipolar diffusion. The shock wave is assumed to be locally plane parallel and steady. The results are sensitive to the thermodynamics employed in the calculations, because it determines the shock structure and the stability of the core. Shocks with velocities in the range of 20-45 km s(-1) are capable of triggering collapse, while those with lower speeds rarely do. The results also depend on the properties of the preimpact core. Highly evolved cores with high initial densities are easier to trigger into collapse, and they tend to collapse to a single point. Less evolved cores with lower densities and larger radii may fragment during collapse and form binaries. C1 Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Vanhala, HAT (reprint author), Carnegie Inst Washington, Dept Terr Magnetism, 5241 Broad Branch Rd NW, Washington, DC 20015 USA. EM harri@dtm.ciw.edu; acameron@cfa.harvard.edu NR 102 TC 78 Z9 79 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 NOV 20 PY 1998 VL 508 IS 1 BP 291 EP 307 DI 10.1086/306396 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LX UT WOS:000077780000024 ER PT J AU Luhman, KL Rieke, GH Lada, CJ Lada, EA AF Luhman, KL Rieke, GH Lada, CJ Lada, EA TI Low-mass star formation and the initial mass function in IC 348 SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; stars : evolution; stars : formation; stars : low-mass, brown dwarfs; stars : luminosity function, mass function; stars : pre-main-sequence ID NEAR-INFRARED SPECTRA; YOUNG STELLAR OBJECTS; RHO-OPHIUCHI CLUSTER; T-TAURI STARS; MAIN-SEQUENCE STARS; EVOLUTIONARY STATUS; SOLAR NEIGHBORHOOD; GLOBULAR-CLUSTERS; STANDARD STARS; POPULATION AB We have performed deep infrared and optical spectroscopy of virtually the entire stellar population within the 5' x 5' core of IC 348, measuring K (2.2 mu m) band and optical spectral types that are in good agreement. We have also identified several sources that may be substellar depending on the choice of temperature scales and evolutionary tracks, with three particularly late-type objects (M7.5-M8) that are likely bonafide brown dwarfs. In conjunction with the theoretical evolutionary tracks of D'Antona & Mazzitelli, the H-R diagram indicates a spread in ages from 0.5 to 10 Myr, with most of the core star formation occurring in the last 3 Myr. Using K-band imaging to provide a completeness correction to the spectroscopic sample, we arrive at an initial mass function (IMF) that matches that of Miller & Scale from 0.25 to 3 M.. The IMF appears to fall slowly from 0.25 M. to the hydrogen burning limit, slightly below the IMF of Miller & Scale, which is flat in logarithmic units (as compared to slopes of similar to 1.35 and -2.6 for Salpeter and Scalo). Correction for unresolved binary systems could steepen the slope of the low-mass IMF by about 0.5, which implies a single-star IMF that is roughly flat below 0.25 M,. The low-mass IMF in IC 348 is similar to that derived in studies of most other young clusters, implying that the IMF does not vary dramatically among clusters of differing environments; however, the derived IMF is dependent on the evolutionary tracks and the detailed shape of the IMF should be viewed with caution until these models are tested against observations, particularly at low masses (<0.3 M.) and young ages (<10 Myr). H alpha and Br gamma emission strengths are consistent with predictions of magnetospheric accretion models of Muzerolle, Calvet, & Hartmann for accretion rates of 10(-9)-10(-8) M. yr(-1). Combining our data with the H alpha measurements of Herbig, we find that similar to 25% of stars within the core of IC 348 and younger than 3 Myr exhibit signatures of disks in the form of strong H alpha (>10 Angstrom) or Br gamma (>1 Angstrom) emission or K-band continuum veiling (r(K) greater than or equal to 0.5). Since no sources older than 3 Myr show evidence for massive disks, disk lifetimes in the core of IC 348 appear to be shorter than those observed in Taurus or in the outer regions of IC 348. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florida, Dept Astron, Gainesville, FL 32611 USA. RP Luhman, KL (reprint author), Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. EM kluhman@as.arizona.edu; grieke@as.arizona.edu; clada@bok.harvard.edu; lada@astro.ufl.edu NR 77 TC 154 Z9 155 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 NOV 20 PY 1998 VL 508 IS 1 BP 347 EP 369 DI 10.1086/306393 PN 1 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LX UT WOS:000077780000028 ER PT J AU Raymond, JC Fineschi, S Smith, PL Gardner, L O'Neal, R Ciaravella, A Kohl, JL Marsden, B Williams, GV Benna, C Giordano, S Noci, G Jewitt, D AF Raymond, JC Fineschi, S Smith, PL Gardner, L O'Neal, R Ciaravella, A Kohl, JL Marsden, B Williams, GV Benna, C Giordano, S Noci, G Jewitt, D TI Solar wind at 6.8 solar radii from UVCS observation of comet C/1996Y1 SO ASTROPHYSICAL JOURNAL LA English DT Article DE comets : individual (C/1996Y1); shock waves; solar wind ID SHOCKS AB The comet C/1996Y1, a member of the Kreutz family of Sun-grazing comets, was observed with the Ultraviolet Coronagraph Spectrometer (UVCS) aboard the Solar and Heliospheric Observatory (SOHO) satellite. The Ly alpha line profile and spatial distribution are interpreted in terms of the theory of bow shocks driven by mass-loading. At the time of the observation, the comet was 6.8 R. from the Sun in a region of high-speed wind, a region difficult to observe directly with the SOHO instruments but an important region for testing models of solar wind acceleration and heating. We find a solar wind speed below 640 km s(-1) and a constraint on the combination of solar wind speed and proton temperature. The total energy per proton at 6.8 R, is 50%-75% of the energy at 1 AU, indicating that significant heating occurs at larger radii. The centroid and width of the Ly alpha line generally confirm the predictions of models of the cometary bow shock driven by mass-loading as cometary molecules are ionized and swept up in the solar wind. We estimate an outgassing rate of 20 kg s(-1), which implies an active area of the nucleus only about 6.7 m in diameter at 6.8 R.. This is likely to be the size of the nucleus, because any inert mantle would have probably been blown off during the approach to the Sun. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Osservatorio Astron Torino, I-10025 Pino Torinese, Italy. Univ Florence, I-50125 Florence, Italy. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. RP Raymond, JC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Giordano, Silvio/0000-0002-3468-8566 NR 24 TC 36 Z9 36 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 NOV 20 PY 1998 VL 508 IS 1 BP 410 EP 417 DI 10.1086/306391 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LX UT WOS:000077780000033 ER PT J AU Lo, KY Shen, ZQ Zhao, JH Ho, PTP AF Lo, KY Shen, ZQ Zhao, JH Ho, PTP TI Intrinsic size of Sagittarius A*: 72 Schwarzschild radii SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; Galaxy : center; scattering ID STELLAR PROPER MOTIONS; SOURCE SGR-A; GALACTIC-CENTER; SCINTILLATION; TURBULENCE; LIMIT; MODEL; VLBI AB Recent proper motion studies of stars at the very center of the Galaxy strongly suggest that Sagittarius A*, the compact nonthermal radio source at the Galactic center, is a 2.5 x 10(6) M. black hole. By means of near-simultaneous multiwavelength Very Long Baseline Array measurements, we determine for the first time the intrinsic size and shape of Sgr A* to be 72 R-sc(star) by less than 20 R-sc(star), with the major axis oriented essentially north-south, where R-sc(star)(= 7.5 x 10(11) cm) is the Schwarzschild radius for a 2.5 x 10(6) M. black hole. Contrary to previous expectation that the intrinsic structure of Sgr A* is observable only at lambda less than or equal to 1 mm, we can discern the intrinsic source size at lambda = 7 mm because (1) the scattering size along the minor axis is half that along the major axis and (2) the near-simultaneous multiwavelength mapping of Sgr A* with the same interferometer makes it possible to extrapolate precisely the minor axis scattering angle at lambda = 7 mm. The intrinsic size and shape place direct constraints on the various emission models for Sgr A*. In particular, the advection-dominated accretion flow model may have to incorporate a radio jet in order to account for the structure of Sgr A*. C1 Acad Sinica, Inst Astron & Astrophys, Taipei 115, Taiwan. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Acad Sinica, Shanghai Observ, Shanghai 200030, Peoples R China. RP Lo, KY (reprint author), Acad Sinica, Inst Astron & Astrophys, POB 1-87, Taipei 115, Taiwan. NR 28 TC 83 Z9 84 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 1998 VL 508 IS 1 BP L61 EP L64 DI 10.1086/311726 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MA UT WOS:000077780300015 ER PT J AU Vilhu, O Nevalainen, J AF Vilhu, O Nevalainen, J TI Two-phase modeling of the rings in the RXTE two-color diagram of GRS 1915+105 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; binaries : close; black hole physics; instabilities; stars : individual (GRS 1915+105); X-rays : stars ID GRS-1915+105 AB The Galactic superluminal source GRS 1915+105 was found to experience a peculiar X-ray variability in a narrow count rate range (9300-12,100 counts s(-1), 5 PCUs) of the Proportional Counter Array on board the Rossi X-Ray Timing Explorer. This can be seen as a ring-shaped pattern in the two-color diagram of count rates, where the hard hardness F(13-40 keV)/F(2-13 keV) is plotted against the soft hardness F(5-13 keV)/F(2-5 keV). The system runs one cycle with periods ranging between 50 and 100 s for different observations, one rotation in the two-color diagram corresponding to the time between two contiguous maxima in the light curve. We model this behavior successfully with the help of a self-consistent two-phase thermal model in which seed photons from an optically thick classical disk are Comptonized in a hot spherical corona surrounding the inner disk (Poutanen & Svensson; Vilhu et al.; Nevalainen et al.). In the model, changes of two parameters regulate the paths in the two-color diagram: the blackbody temperature T-in of the inner disk and the Thomson optical depth multiplied by the electron temperature of the hot phase tau T-e. These parameters oscillate with time but with a phase shift between each other, causing the ring-shaped pattern. During the observation studied in more detail (20402-01-30-00), the inner disk radius varied with a 97 a period between 20 and 35 km with an anticorrelation between the coronal tau T-e and the mass accretion rate (M) over dot through the disk, possibly indicating a coupling between the disk and coronal accretion. During a typical cycle, the inner disk radius rapidly shrank and returned more slowly back to the original larger value. In the rings we may see phenomena close to the black hole horizon under near Eddington accretion rates. C1 Helsinki Univ Observ, SF-00140 Helsinki, Finland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 01238 USA. RP Vilhu, O (reprint author), Helsinki Univ Observ, POB 14, SF-00140 Helsinki, Finland. NR 14 TC 25 Z9 26 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 1998 VL 508 IS 1 BP L85 EP L89 DI 10.1086/311709 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MA UT WOS:000077780300020 ER PT J AU Ferrarese, L Bresolin, F Kennicutt, RC Saha, A Stetson, PB Freedman, WL Mould, JR Madore, BF Sakai, S Ford, HC Gibson, BK Graham, JA Han, MS Hoessel, JG Huchra, J Hughes, SM Illingworth, GD Phelps, R Prosser, CF Silbermann, NA AF Ferrarese, L Bresolin, F Kennicutt, RC Saha, A Stetson, PB Freedman, WL Mould, JR Madore, BF Sakai, S Ford, HC Gibson, BK Graham, JA Han, MS Hoessel, JG Huchra, J Hughes, SM Illingworth, GD Phelps, R Prosser, CF Silbermann, NA TI The Hubble Space Telescope key project on the extragalactic distance scale. XII. The discovery of Cepheids and a new distance to NGC 2541 SO ASTROPHYSICAL JOURNAL LA English DT Article DE Cepheids; galaxies : distances and redshifts; galaxies : individual (NGC 2541) ID ABSOLUTE PEAK BRIGHTNESS; BVRI CCD PHOTOMETRY; VARIABLE-STARS; NEARBY GALAXIES; INFRARED PHOTOMETRY; CALIBRATION; CONSTANT; PERFORMANCE; EXTINCTION; WFPC2 AB We report the detection of Cepheids and a new distance to the spiral galaxy NGC 2541, based on data obtained with the Wide Field Planetary Camera 2 on board the Hubble Space Telescope (HST). A total of 25 exposures (divided into 13 epochs) were obtained using the F555W filter (transformed to Johnson V), and nine exposures were obtained (divided into five epochs) using the F814W filter (transformed to Cousins I). Photometric reduction of the data is performed using two independent packages, DoPHOT and DAOPHOT II/ALLFRAME, which give very good agreement in the measured magnitudes. A total of 34 bona fide Cepheids, with periods ranging from 12 to over 60 days, are identified based on both sets of photometry. By fitting V and I period-luminosity relations, apparent distance moduli are derived assuming a Large Magellanic Cloud distance modulus and mean color excess of mu(LMC) = 18.50 +/- 0.10 mag and E(B - V) = 0.10 mag, respectively. Adopting A(V)/E(V - I) = 2.45, we obtain a true distance modulus to NGC 2541 of mu(0) = 30.47 +/- 0.11 (random) +/- 0.12 (systematic) mag (D = 12.4 +/- 0.6 [random] +/- 0.7 [systematic] Mpc), and a total (Galactic plus internal) mean color excess E(B - V) = 0.08 +/- 0.05 (internal error) mag. C1 CALTECH, Pasadena, CA 91125 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. European So Observ, D-8046 Garching, Germany. Kitt Peak Natl Observ, Natl Opt Astron Observ, Tucson, AZ 85726 USA. Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Inst Adv Studies, Weston, ACT 2611, Australia. NASA, IPAC Extragalact Database, Pasadena, CA 91125 USA. Carnegie Inst Washington, Dept Terr Magnetism, Baltimore, MD 21218 USA. Univ Wisconsin, Madison, WI 53706 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 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 70 TC 28 Z9 28 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1998 VL 507 IS 2 BP 655 EP 690 DI 10.1086/306364 PN 1 PG 36 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LU UT WOS:000077779700010 ER PT J AU O'Neal, D Neff, JE Saar, SH AF O'Neal, D Neff, JE Saar, SH TI Measurements of starspot parameters on active stars using molecular bands in echelle spectra SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : spectroscopic; stars : activity; stars : fundamental parameters; stars : late-type; stars : spots ID RS-CANUM-VENATICORUM; ROTATIONAL-MODULATION; II-PEGASI; CHROMOSPHERIC ACTIVITY; LAMBDA-ANDROMEDAE; BINARY-SYSTEMS; URSAE MAJORIS; M-DWARFS; X-RAY; CVN AB We present results from a study of starspot areas (f(s)) and temperatures (T-s), primarily on active, single-lined spectroscopic binaries, determined using molecular absorption bands. Expanding upon out previous studies, we have analyzed multiorder echelle spectra of eight systems to simultaneously measure several different molecular bands and chromospheric emission lines. We determined starspot parameters by fitting the molecular bands of interest, using spectra of inactive G and K stars as proxies for the nonspotted photosphere of the active stars, and using spectra of M stars as proxies for the spots. At least two bands with different T-eff sensitivities are required. We found that fitting bands other than the TiO 7055 and 8860 Angstrom features does not greatly extend the temperature range or sensitivity of our technique. The 8860 Angstrom band is particularly important because of its sharply different temperature sensitivity. We did not find any substantial departures from f(s) or T-s that we have measured previously based on single-order spectra. We refined our derived spot parameters using contemporaneous photometry where available. We found that using M giants as spot proxies for subgiant active stars often underestimates fs needed to fit the photometry; this is presumably due to the increase in strength of the TiO bands with decreasing gravity. We also investigated correlations between f(s) and chromospheric emission, and we developed a simple method to measure nonspot temperature (T-Q) solely from our echelle spectra. C1 Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Coll Charleston, Dept Phys & Astron, Charleston, SC 29424 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP O'Neal, D (reprint author), Univ Colorado, Joint Inst Lab Astrophys, Campus Box 440, Boulder, CO 80309 USA. NR 51 TC 64 Z9 64 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 NOV 10 PY 1998 VL 507 IS 2 BP 919 EP 937 DI 10.1086/306340 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LU UT WOS:000077779700027 ER PT J AU Charbonneau, D Jha, S Noyes, RW AF Charbonneau, D Jha, S Noyes, RW TI Spectral line distortions in the presence of a close-in planet SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems; stars : individual (tau Bootis, 51 Pegasi); techniques : spectroscopic ID SUN-LIKE STARS; 51-PEGASI AB We discuss the interpretation of the distortions to the stellar spectral lines, with particular attention to line bisectors in the presence of an orbiting planetary companion. We present a simple model whereby light reflected by the companion can cause temporal variations to the observed line profiles. These distortions have a characteristic signature that depends on the inclination angle of the system. For the known close-in extrasolar giant planets, the expected amplitude of the effect might not be far from current detection capabilities. This method could be used to detect the presence of the companion directly, yielding the orbital inclination and hence the planetary mass. Furthermore, a detection would measure a combination of the planetary radius and albedo, from which a minimum radius may be deduced. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Charbonneau, D (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 19 TC 11 Z9 11 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1998 VL 507 IS 2 BP L153 EP L156 DI 10.1086/311703 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LW UT WOS:000077779900013 ER PT J AU Myers, PC Lazarian, A AF Myers, PC Lazarian, A TI Turbulent cooling flows in molecular clouds SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; MHD; stars : formation; turbulence ID STAR-FORMATION; HYDROMAGNETIC-WAVES; INTERSTELLAR CLOUDS; CORES; MODEL AB We propose that inward, subsonic flows arise from the local dissipation of turbulent motions in molecular clouds. Such "turbulent cooling flows" may account for recent observations of spatially extended inward motions toward dense cores. These pressure-driven flows may arise from various types of turbulence and dissipation mechanisms. For the example of MHD waves and turbulence damped by ion-neutral friction, sustained cooling flow requires that the outer gas be sufficiently turbulent, that the inner gas have marginal field-neutral coupling, and that this coupling decrease sufficiently rapidly with increasing density. These conditions are most likely met at the transition between outer regions ionized primarily by UV photons and inner regions ionized primarily by cosmic rays. If so, turbulent cooling flows can help form dense cores, with speeds faster than expected for ambipolar diffusion. Such motions could reduce the time needed for dense core formation and could precede and enhance the motions of star-forming gravitational infall. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. RP Myers, PC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM pmyers@cfa.harvard.edu; lazarian@astro.princeton.edu NR 43 TC 76 Z9 76 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 NOV 10 PY 1998 VL 507 IS 2 BP L157 EP L160 DI 10.1086/311700 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LW UT WOS:000077779900014 ER PT J AU Zimbelman, JR AF Zimbelman, JR TI Emplacement of long lava flows on planetary surfaces SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID KILAUEA VOLCANO; ANALOG EXPERIMENTS; SHEET FLOWS; ALBA-PATERA; ERUPTION; VENUS; MORPHOLOGY; HAWAII; MARS; TERRESTRIAL AB Three long lava flows on Mars, Venus, and the Moon were examined in order to evaluate their possible emplacement rate and condition. On the Moon, flows of the last (phase III) effusion within the Imbrium impact basin were examined using Apollo photography. The longest phase III flow can be followed for 250 km, terminating similar to 400 km from the probable source vent. This flow has a width of 10 to 25 km, thickness of 10 to 30 m, and a medial channel preserved in its proximal reach, and it was emplaced on a regional slope of similar to 0.3 degrees: In the Tharsis region of Mars, a well-defined set of lava flows extends north from the topographic saddle between Ascraeus and Pavonis Montes. Viking Orbiter images show one flow that can be traced for 480 km, with a width ranging from 5 to 50 km, thickness of 30 to 100 m, and a prominent medial channel in its proximal reach, and was emplaced on a regional slope of similar to 0.5 degrees to similar to 0.1 degrees. The Strenia Fluctus area on Venus consists of an array of intermixed radar-bright and radar-dark lobate flows, one of which can be traced for 180 km, with a width of 5 to 20 km, and an unknown thickness (but inferred to be similar to 30 m), and was emplaced on the lowland plains where the regional slope is only similar to 0.03 degrees. When viewed at the full Magellan resolution, this flow contains several flow margins, indicating its compound nature. Effusion rates were calculated for the simple lunar and Martian flows using published empirical and theoretical relationships, resulting in a broad range of 500 to 10(8) (Moon) and 600 to 2 x 10(8) (Mars) m(3)/s, with most likely values of similar to 5 x 10(4) to similar to 10(5) for both flows. The compound Venus flow would have required 494 years for emplacement at the typical Kilauea tate of similar to 5 m(3)/s, but the thermal balance of planetary tube systems could also be consistent with a rate at least an order of magnitude larger. The distinction between simple and compound flows is important to any evaluation of flow emplacement based solely on remote sensing data. C1 Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. RP Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, 6th & Independence Ave SW, Washington, DC 20560 USA. EM jrz@ceps.nasm.edu NR 87 TC 33 Z9 34 U1 1 U2 4 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 NOV 10 PY 1998 VL 103 IS B11 BP 27503 EP 27516 DI 10.1029/98JB01123 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 137MQ UT WOS:000076918900039 ER PT J AU Mann, RW Feather, ME Tumosa, CS Holland, TD Schneider, KN AF Mann, RW Feather, ME Tumosa, CS Holland, TD Schneider, KN TI A blue encrustation found on skeletal remains of Americans missing in action in Vietnam SO FORENSIC SCIENCE INTERNATIONAL LA English DT Article DE vivianite; bone; iron II phosphate; blue encrustation; MIA; taphonomy AB A blue encrustation was found on the repatriated remains of three U.S. Servicemen listed as missing in action (MIA) from Vietnam after 28 years. The identification and origin of the blue material was determined. Scanning electron microscopy with energy dispersive analysis and powder X-ray diffraction identified the material as the mineral vivianite, Fe-3(PO4)(2). 8H(2)O. Vivianite has been found often associated with fossilized bone and teeth, but this example is unusual in that it is only the second published forensic example of vivianite growing from human bone after such a short period of time. The presence of vivianite provides information leading to a more complete and accurate understanding of the taphonomic process associated with American MIA remains. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 USA, Cent Identificat Lab, Hickam AFB, HI 96853 USA. Smithsonian Inst, Conservat Analyt Lab, Washington, DC 20560 USA. RP Mann, RW (reprint author), USA, Cent Identificat Lab, 310 Worchester Ave, Hickam AFB, HI 96853 USA. NR 11 TC 13 Z9 14 U1 1 U2 2 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0379-0738 J9 FORENSIC SCI INT JI Forensic Sci.Int. PD NOV 9 PY 1998 VL 97 IS 2-3 BP 79 EP 86 DI 10.1016/S0379-0738(98)00026-7 PG 8 WC Medicine, Legal SC Legal Medicine GA 147NY UT WOS:000077574400001 PM 9871987 ER PT J AU Visscher, PT Reid, RP Bebout, BM Hoeft, SE Macintyre, IG Thompson, JA AF Visscher, PT Reid, RP Bebout, BM Hoeft, SE Macintyre, IG Thompson, JA TI Formation of lithified micritic laminae in modern marine stromatolites (Bahamas): The role of sulfur cycling SO AMERICAN MINERALOGIST LA English DT Article ID SOLAR LAKE SINAI; CYANOBACTERIAL MATS; SULFATE REDUCTION; SUBTIDAL STROMATOLITES; MICROBIAL MATS; EXUMA-CAYS; SEDIMENTS; SULFIDE; DISSOLUTION; OXYGEN AB Microbial mats on the surfaces of modern, marine stromatolites at Highborne Gay, Bahamas, were investigated to assess the role of microbial processes in stromatolite formation. The Highborne Cay stromatolitic mats contain Schizothix as the dominant cyanobacterium and show millimeter-scale lamination: Some layers in the mat are soft (unlithified), whereas other layers are crusty (lithified). Lithified layers within the mats correspond to micritic horizons composed of thin (20-50 mu m) micritic crusts, which commonly overlie truncated, micritized carbonate sand grains. These features are identical to lithified laminae in the underlying stromatolite; the micritic crusts are similar in thickness to micritic laminae in many ancient stromatolites. Biogeochemical parameters in a representative stromatolitic mat from Highborne Cay were measured to identify the role of bacteria in precipitation and dissolution of CaCO3. Depth distributions of O-2, HS-, and pH were determined with microelectrode measurements in the field. Oxygen profiles were used to calculate photosynthesis and aerobic respiration. Sulfate reduction was determined using (SO42-)-S-35 and sulfide oxidation potential was measured in homogenized samples. Our results indicate that cyanobacterial photosynthesis, sulfate reduction, and anaerobic sulfide oxidation in stromatolitic mats at Highborne Cay are responsible for CaCO3 precipitation, whereas aerobic respiration and aerobic sulfide oxidation cause CaCO3 dissolution. A close coupling of photosynthesis and aerobic respiration in the uppermost few millimeters of the mats results in no, or very little, net lithification. Sulfur cycling, on the other hand, shows a close correlation with the formation of lithified micritic layers. Photosynthesis, combined with sulfate reduction and sulfide oxidation results in net lithification. Sulfate reduction rates are high in the uppermost lithified layer and, on a diel basis, consume 33-38% of the CO2 fixed by the cyanobacteria. In addition, this lithified layer contains a significant population of sulfide-oxidizing bacteria and shows a high sulfide oxidation potential. These findings argue that photosynthesis coupled to sulfate reduction and sulfide oxidation is more important than photosynthesis coupled to aerobic respiration in the formation of lithified micritic laminae in Highborne Cay stromatolites. C1 Univ Connecticut, Dept Marine Sci, Groton, CT 06340 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine Geol & Geophys, Miami, FL 33149 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. Tabor Acad, Marion, MA 02738 USA. RP Visscher, PT (reprint author), Univ Connecticut, Dept Marine Sci, Groton, CT 06340 USA. EM visscher@uconnvm.uconn.edu NR 46 TC 156 Z9 160 U1 3 U2 19 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 NOV-DEC PY 1998 VL 83 IS 11-12 BP 1482 EP 1493 PN 2 PG 12 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 145YE UT WOS:000077399200009 ER PT J AU Morton, ES AF Morton, Eugene S. TI Pairing in mallards and American black ducks: a new view on population decline in American black ducks SO ANIMAL CONSERVATION LA English DT Article AB Data on mating systems suggest that mate choice and dominance advantages by mallard (Anas platyrhynchos) males are not sufficient to explain declines in American black ducks (Anas rubripes). Courtship and pairing of mallards and American black ducks overwintering at a site on the Chesapeake Bay were studied from 1976-1993, during October-March. Mallards declined relative to American black ducks during this period at the study site. Courtship groups and pairs (one exception) consisted of conspecific individuals. Mallards and American black ducks segregated when courting but not when resting. Hybrid males joined courting groups of either species but did not pair successfully with either parental species. Handraised American black ducks hatched from eggs, imprinted on humans, and fledged at the study site, paired with American black ducks even though they were initially the rarer species. Handraised American black ducks avoided pairing with siblings. American black ducks and mallards pair assortatively and hybrids are selected against on the Chesapeake Bay. American black ducks may be declining due to human disturbance rather than due to direct interactions with mallards. Mallards may be increasing because they tolerate human disturbance and through direct release by humans into the American black duck's breeding range. C1 Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Morton, ES (reprint author), Conservat & Res Ctr, Natl Zool Pk,1500 Remount Rd, Front Royal, VA 22630 USA. EM NZPEM034@SIVM.SI.EDU FU Friends of the National Zoo FX I thank S. R. Derrickson, J. Gittleman, F. Rohwer, B. J. M. Stutchbury and one anonymous reviewer for improving the manuscript. The Friends of the National Zoo provided support. I am particularly grateful to the keeper staff at the Conservation and Research Center (CRC) for raising black ducks, and to Cathy Caplan for her work on the captive flock at CRC. NR 38 TC 7 Z9 9 U1 2 U2 10 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 1367-9430 J9 ANIM CONSERV JI Anim. Conserv. PD NOV PY 1998 VL 1 IS 4 BP 239 EP 244 DI 10.1111/j.1469-1795.1998.tb00034.x PG 6 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA V71EF UT WOS:000204810500002 ER PT J AU Eberhard, WG AF Eberhard, WG TI Sexual behavior of Acanthocephala declivis guatemalana (Hemiptera : Coreidae) and the allometric scaling of their modified hind legs SO ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA LA English DT Article DE Acanthocephala; Coreidae; sexual behavior; weapons; visual display traits ID MATE CHOICE; LEPTOGLOSSUS-AUSTRALIS; FABRICIUS HETEROPTERA; BODY-SIZE; BUG; DISPLAY; AGGREGATION; DIOPSIDAE; SELECTION; DIPTERA AB The sexually dimorphic hind legs of Acanthocephala declivis guatemalana are used for different functions in males and females, and they scale differently on body size. The hind legs of males are used to deliver powerful squeezes to other males in battles at feeding and mating sites, and the diameter of the hind femur and the length of its large tooth are proportionally larger in large males compared with other body characters. The largest tooth on the female hind femur probably functions in the less forceful female-female battles, and it is also proportionally larger in large females. However, neither the female hind tibial plate, which is used as an aggressive signaling device, nor the diameter of the female hind femur are proportionally larger in large females. Wing wear and breakage of hind leg spines, combined with behavioral observations of marked bugs, indicate that the breeding system combines elements of resource defense polygyny and lek polygyny. Females mate more than once, despite the attendant cost of reduced feeding opportunities. C1 Univ Costa Rica, Smithsonian Trop Res Inst, San Jose, Costa Rica. Univ Costa Rica, Escuela Biol, San Jose, Costa Rica. RP Eberhard, WG (reprint author), Univ Costa Rica, Smithsonian Trop Res Inst, San Jose, Costa Rica. NR 32 TC 35 Z9 36 U1 2 U2 9 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 NOV PY 1998 VL 91 IS 6 BP 863 EP 871 PG 9 WC Entomology SC Entomology GA 144QC UT WOS:000077325100016 ER PT J AU Koranyi, DM Geller, MJ Mohr, JJ Wegner, G AF Koranyi, DM Geller, MJ Mohr, JJ Wegner, G TI A photometric and kinematic study of AWM 7 SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : clusters : individual (AWM 7); galaxies : luminosity function, mass function ID GALAXY LUMINOSITY FUNCTION; X-RAY-EMISSION; POOR CLUSTERS; RICH CLUSTERS; COMA CLUSTER; CD GALAXIES; VELOCITY DISPERSIONS; REDSHIFT SURVEY; DWARF GALAXIES; FAINT END AB We have measured redshifts and Kron-Cousins R-band magnitudes for a sample of galaxies in the poor cluster AWM 7. We have measured redshifts for 172 galaxies; 106 of these are cluster members. We determine the luminosity function (LF) from a photometric survey of the central 1.2 x 1.2 h(-1) Mpc. The LF has a bump at the bright end and a faint-end slope of alpha = -1.37 +/- 0.16, populated almost exclusively by absorption-line galaxies. The cluster velocity dispersion is lower in the core (similar to 530 km s(-1)) than at the outskirts (similar to 680 km s(-1)), consistent with the cooling flow seen in the X-ray. The cold core extends similar to 150 h(-1) kpc from the cluster center. The Kron-Cousins R-band mass-to-light ratio of the system is 650 +/- 170 h M./L., substantially lower than previous optical determinations, but consistent with most previous X-ray determinations. We adopt H-0 = 100 h km s(-1) Mpc(-1) throughout this paper; at the mean cluster redshift (5247 +/- 76 km s(-1)), 1 h(-1) Mpc subtends 65.'5. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 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; jjmohr@umich.edu; wegner@kayz.dartmouth.edu NR 69 TC 14 Z9 14 U1 0 U2 1 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 NOV PY 1998 VL 116 IS 5 BP 2108 EP 2118 DI 10.1086/300611 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 134UZ UT WOS:000076763200004 ER PT J AU Uitenbroek, H Dupree, AK Gilliland, RL AF Uitenbroek, H Dupree, AK Gilliland, RL TI Spatially resolved Hubble Space Telescope spectra of the chromosphere of alpha Orionis SO ASTRONOMICAL JOURNAL LA English DT Article DE stars : chromospheres; stars : imaging; stars : individual (alpha Orionis); stars : rotation; supergiants ID RED GIANTS; BETELGEUSE; POLARIZATION; ATMOSPHERES; SUPERGIANTS; ASYMMETRY; STAR; LINE AB Spatially resolved UV spectra of the supergiant a Orionis (Betelgeuse) obtained in 1995 March with the Goddard High Resolution Spectrograph (GHRS) on board the Hubble Space Telescope (HST) show that the chromospheric emission in the Mg II h and k; (around 280 nm) lines reaches a diameter of at least similar to 270 milliarcseconds, about twice the size of ultraviolet continuum images obtained at the same time with the HST Faint Object Camera (FOC), and about 5 times the star's optical diameter. The signature of the unresolved bright spot observed in the 1995 March FOC images occurs in the spectrum as an asymmetry in the intensity measured across the disk at constant wavelength. Because the spectra were obtained scanning across the stellar image, it is possible to measure a differential line shift across the disk of the star that can be interpreted as being due to rotation. If this interpretation is correct, we can determine the axis of rotation of Betelgeuse and estimate its rotational speed to be 1.2 x 10(-8) rad s(-1), corresponding to a rotation period of 17 yr. In addition, it is plausible that the 1995 March bright spot is congruent with the pole of the star, suggesting that star's angle of inclination is similar to 20 degrees to the line of sight. Considering the small number of bright spots that are present at any one time on the surface of Betelgeuse, and the signature of the 1995 March spot in the Mg II resonance lines as observed with the GHRS, it appears that such spots are not the consequence of convective flows. Differences in the spatial distribution of the flux emerging from different layers of the atmosphere and the line asymmetries of the Mg II h and k lines suggest that the spot is the signature of an outwardly propagating shock wave in an atmosphere modified by rotation. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Uitenbroek, H (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 38 TC 56 Z9 56 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 1998 VL 116 IS 5 BP 2501 EP 2512 DI 10.1086/300596 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 134UZ UT WOS:000076763200035 ER PT J AU Nevalainen, J Roos, M AF Nevalainen, J Roos, M TI Cepheid metallicity and Hubble constant SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE distance scale; stars : variables : cepheids; methods : statistical; galaxies : distances and redshifts; galaxies : abundances ID EXTRAGALACTIC DISTANCE SCALE; SPACE-TELESCOPE; SPIRAL GALAXIES; DISCOVERY; M100; IA AB This study combines data from a set of seven Cepheid-calibrated galaxies in Virgo, Leo I and Fornax and four supernova: with known metallicities, including metallicity corrections to the Cepheid distances, in order to determine a consistent mean value for the Hubble constant. We derive Virgo and Coma distances over different paths, starting from the metallicity corrected Cepheid distances of Virgo and Leo I galaxies, and we relate them to the Virgo and the Coma recession velocities, paying special attention to thereby introduced correlations. We also determine the velocity of the Fornax cluster and relate this velocity to its distance. In addition we use the standard constant maximum brightness SN Ia method, as well as results from multicolor light curve shape (MLCS) analysis of SNe Ia, to derive the Hubble constant. Using the requirement of statistical consistency, our data set determines the value of the metallicity coefficient (the change in magnitude per factor of ten in metal abundance) to be 0.31(-0.14)(+0.15) in good agreement with other known determinations. We also use consistency as a criterion to select between mutually exclusive data sets, such as the two known, but conflicting, Virgo recession velocities (in favor of the lower value), as well as between two different analyses of (partly) the same supernovae (in favor of MLCS analysis). When combining data we pay attention to the statistically correct handling of common errors. Our result is a Hubble constant with the value H-0 = 68 +/- 5 km s(-1) Mpc(-1). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Helsinki Observ, FIN-00014 Helsinki, Finland. Univ Helsinki, Dept Phys, Div High Energy Phys, FIN-00014 Helsinki, Finland. RP Nevalainen, J (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM jukka@head-cfa.harvard.edu NR 39 TC 12 Z9 12 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD NOV 1 PY 1998 VL 339 IS 1 BP 7 EP 14 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 134GU UT WOS:000076735600010 ER PT J AU Benedettini, M Nisini, B Giannini, T Lorenzetti, D Tommasi, E Saraceno, P Smith, HA AF Benedettini, M Nisini, B Giannini, T Lorenzetti, D Tommasi, E Saraceno, P Smith, HA TI ISO-SWS observations of Herbig Ae/Be stars: HI recombination lines in MWC1080 and CoD -42 degrees 11721 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : pre-main sequence; circumstellar matter stars : mass-loss; stars : individual : MWC1080; stars : individual : CoD -42 degrees 11721; infrared : stars ID RADIO-CONTINUUM EMISSION; SHORT-WAVELENGTH SPECTROMETER; MAIN-SEQUENCE STARS; INFRARED-EMISSION; CD-42-DEGREES-11721; IONIZATION; WINDS AB ISO-SWS grating spectra are obtained towards the two Herbig Ae/Be stars MWC1080 and CoD -42 degrees 11721, showing hydrogen recombination lines of the Brackett, Pfund and Humphreys series. The observed line decrements in each spectral series are consistent with emission from ionized winds, as expected from these early-type stars. We compare the observed line emission with a wind model assuming a constant rate of mass flow from the star, which allows to consistently derive mass loss rate and distance of both stars. We also show that the observed decrements can only be explained by assuming a ionization bounded compact regions whose sizes are a few tens of the stellar radii. C1 CNR, Ist Fis Spazio Interplanetario, Area Ric Tor Vergata, I-00133 Rome, Italy. Osserv Astron Roma, I-00040 Monte Porzio Catone, Italy. ISO, Sci Operat Ctr, E-28080 Madrid, Spain. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Benedettini, M (reprint author), CNR, Ist Fis Spazio Interplanetario, Area Ric Tor Vergata, Via Fosso Cavaliere, I-00133 Rome, Italy. EM milena@sirius.ifsi.rm.cnr.it NR 23 TC 19 Z9 19 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 NOV 1 PY 1998 VL 339 IS 1 BP 159 EP 164 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 134GU UT WOS:000076735600026 ER PT J AU Guainazzi, M Comastri, A Stirpe, GM Brandt, WN Fiore, F Leighly, KM Matt, G Molendi, S Puchnarewicz, EM Piro, L Siemiginowska, A AF Guainazzi, M Comastri, A Stirpe, GM Brandt, WN Fiore, F Leighly, KM Matt, G Molendi, S Puchnarewicz, EM Piro, L Siemiginowska, A TI 1H0419-577: a "two-state" soft X-ray Seyfert galaxy SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE X-rays : galaxies; galaxies : Seyfert; galaxies : individual : 1H0419-577 ID ACTIVE GALACTIC NUCLEI; BROAD-LINE REGION; ACCRETION DISKS; ASTRONOMY SATELLITE; COLD MATTER; BLACK-HOLE; ON-BOARD; EMISSION; SPECTRA; MODELS AB In this paper we report on the first simultaneous optical and X-ray (Beppo-SAX) observations of the radio-quiet AGN 1H0419-577. The optical spectrum clearly leads us to classify this source as a Seyfert I. The X-ray spectrum is, however, somewhat at odds with this classification: a simple flat (Gamma similar to 1.55) and featureless power-law is a good description of the whole 1.8-40 keV spectrum, even if the upper limit to a broad iron line is not very tight. An analysis of a still unpublished ROSAT observation of the same target reveals that the soft X-ray spectrum has undergone a transition from a steep (Gamma = 2.5) to a flat (Gamma = 1.55) state, at least in the 0.7-2 keV band. If this difference is due to a remarkably variable soft excess, it is unlikely that a single component is responsible for the optical/UV/soft X-ray spectral distribution. The hypothesis that the difference is due to a change in the primary X-ray continuum and its implications for current Comptonization models are discussed. C1 European Space Agcy, Estec, Dept Space Sci, Div Astrophys, NL-2200 AG Noordwijk, Netherlands. Nuova Telespazio, Beppo SAX Sci Data Ctr, I-00131 Rome, Italy. Osservatorio Astron Bologna, I-40126 Bologna, Italy. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Osserv Astron Roma, I-00040 Monte Porzio Catone, RM, Italy. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. Univ Studi Roma 3, Dipartimento Fis, I-00146 Rome, Italy. CNR, Ist Fis Cosm & Tecnol Relat, I-20133 Milan, Italy. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. CNR, Ist Astrofis Spaziale, I-00133 Rome, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Guainazzi, M (reprint author), European Space Agcy, Estec, Dept Space Sci, Div Astrophys, Postbus 299, NL-2200 AG Noordwijk, Netherlands. EM mguainaz@astro.estec.esa.nl RI PIRO, LUIGI/E-4954-2013; Brandt, William/N-2844-2015; Stirpe, Giovanna/O-9393-2015; Comastri, Andrea/O-9543-2015; OI PIRO, LUIGI/0000-0003-4159-3984; Brandt, William/0000-0002-0167-2453; Stirpe, Giovanna/0000-0002-3702-8731; Comastri, Andrea/0000-0003-3451-9970; Molendi, Silvano/0000-0002-2483-278X; Fiore, Fabrizio/0000-0002-4031-4157 NR 54 TC 25 Z9 25 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 NOV PY 1998 VL 339 IS 2 BP 327 EP 336 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 139ED UT WOS:000077014200006 ER PT J AU Mermilliod, JC Mathieu, RD Latham, DW Mayor, M AF Mermilliod, JC Mathieu, RD Latham, DW Mayor, M TI Red giants in open clusters - VIII. NGC 752 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE techniques : radial velocities; binaries : spectroscopic; Hertzsprung-Russel (HR) diagram; open clusters and associations : individual : NGC 2354 ID STELLAR EVOLUTION; RADIAL-VELOCITIES; NGC-752; NGC-3680; BINARITY; MODELS AB The results of an 18-year radial-velocity survey of 30 red giants in the field of the open cluster NGC 752 are presented. The membership of 15 stars is confirmed. Four spectroscopic binaries have been discovered among the members and three orbits have been determined for H75, 110 and 208, with periods of 3321, 127 and 5276 days respectively. The binary frequency (27%) is normal. A search for additional members in a wide surrounding area (2 degrees) yielded two possible new members: both are clump red giant candidates. The red giant distribution in the colour-magnitude diagram is somewhat unusual, with a clump containing 8 stars and a second, fainter feature extending to the blue, defined by 3 or 4 stars, which is not accounted for by theoretical isochrones. C1 Univ Lausanne, Inst Astron, CH-1290 Chavannes Bois, Switzerland. Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Observ Geneva, CH-1290 Sauverny, Switzerland. RP Mermilliod, JC (reprint author), Univ Lausanne, Inst Astron, CH-1290 Chavannes Bois, Switzerland. NR 36 TC 20 Z9 20 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 NOV PY 1998 VL 339 IS 2 BP 423 EP 430 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 139ED UT WOS:000077014200015 ER PT J AU Mewe, R Drake, SA Kaastra, JS Schrijver, CJ Drake, JJ Gudel, M Schmitt, JHMM Singh, KP White, NE AF Mewe, R Drake, SA Kaastra, JS Schrijver, CJ Drake, JJ Gudel, M Schmitt, JHMM Singh, KP White, NE TI alpha Centauri: coronal temperature structure and abundances from ASCA observations SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : coronae; stars : individual : alpha Cen; stars : abundances; X-rays : stars ID EXTREME-ULTRAVIOLET-SPECTRA; SOLAR-LIKE STARS; EMISSION MEASURE; COOL STARS; EUV SPECTROSCOPY; EVOLUTION; SYSTEM; LINES; IONIZATION; ATMOSPHERE AB We have analyzed the X-ray spectrum of the nearby binary alpha Cen AB (G2V + K1V) that has been obtained from observations with ASCA. The coronal temperature structure and abundances have been derived from multi-temperature fitting and confirmed by a differential emission measure analysis. The corona as seen by ASCA is essentially isothermal with a temperature around 0.3 keV, consistent with the evolutionary picture of coronae of aging solar-type stars. A comparison between the measurements from various instruments indicates a source variability in the coronal flux (which precludes the joint fitting of data from different instruments taken at different epochs) and temperature structure consistent with that discovered in a series of ROSAT observations. The elemental abundances agree with solar photospheric abundances for Ne, Si, and Fe at 1 sigma level, while O appears to be underabundant by a factor of about 3 relative to solar photospheric values, and Mg overabundant by a factor of a few. The abundance ratios with respect to Fe are better determined: [O/Fe] = 0.4+/-0.14(x solar, etc.), [Mg/Fe] = 4+/-1, [Ne/Fe] = 1+/-0.3, and [Si/Fe] = 6+/-4. C1 SRON, NL-3584 CA Utrecht, Netherlands. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Stanford Lockheed Inst Space Res, Dept H112, Palo Alto, CA 94304 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. RP Mewe, R (reprint author), SRON, Sorbonnelaan 2, NL-3584 CA Utrecht, Netherlands. EM R.Mewe@sron.nl RI White, Nicholas/B-6428-2012; Guedel, Manuel/C-8486-2015 OI White, Nicholas/0000-0003-3853-3462; Guedel, Manuel/0000-0001-9818-0588 NR 62 TC 5 Z9 5 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 NOV PY 1998 VL 339 IS 2 BP 545 EP 552 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 139ED UT WOS:000077014200030 ER PT J AU Schmidt, BP Suntzeff, NB Phillips, MM Schommer, RA Clocchiatti, A Kirshner, RP Garnavich, P Challis, P Leibundgut, B Spyromilio, J Riess, AG Filippenko, AV Hamuy, M Smith, RC Hogan, C Stubbs, C Diercks, A Reiss, D Gilliland, R Tonry, J Maza, J Dressler, A Walsh, J Ciardullo, R AF Schmidt, BP Suntzeff, NB Phillips, MM Schommer, RA Clocchiatti, A Kirshner, RP Garnavich, P Challis, P Leibundgut, B Spyromilio, J Riess, AG Filippenko, AV Hamuy, M Smith, RC Hogan, C Stubbs, C Diercks, A Reiss, D Gilliland, R Tonry, J Maza, J Dressler, A Walsh, J Ciardullo, R TI The High-Z Supernova Search: Measuring cosmic deceleration and global curvature of the universe using Type IA supernovae SO ASTROPHYSICAL JOURNAL LA English DT Review DE cosmology : observations; galaxies : distances and redshifts; supernovae : general; supernovae : individual (SN 1995K) ID LIGHT-CURVE SHAPES; HUBBLE CONSTANT; WHITE-DWARF; SPECTROPHOTOMETRIC STANDARDS; COSMOLOGICAL PARAMETERS; CCD PHOTOMETRY; TIME DILATION; GALAXIES; DIAGRAM; SN-1991T AB The High-Z Supernova Search is an international collaboration to discover and monitor Type Ia supernovae (SNe Ia) at z > 0.2 with the aim of measuring cosmic deceleration and global curvature. Our collaboration has pursued a basic understanding of supernovae in the nearby universe, discovering and observing a large sample of objects and developing methods to measure accurate distances with SNe Ia. This paper describes the extension of this program to z greater than or equal to 0.2, outlining our search techniques and follow-up program. We have devised high-throughput filters that provide accurate two-color rest frame B and V light curves of SNe Ia, enabling us to produce precise, extinction-corrected luminosity distances in the range 0.25 < z < 0.55. Sources of systematic error from K-corrections, extinction, selection effects, and evolution are investigated, and their effects estimated. We present photometric and spectral observations of SN 1995K, our program's first supernova (SN) and use the data to obtain a precise measurement of the luminosity distance to the z = 0.479 host galaxy. This object, when combined with a nearby sample of SNe, yields an estimate for the matter density of the universe of Omega(M) = -0.2(-0.8)(+1.0) if Omega(Lambda) = 0. For a spatially flat universe composed of normal matter and a cosmological constant, we find Omega(M) = 0.4(-0.4)(+0.5), Omega(Lambda) = 0.6(-0.5)(+0.4). We demonstrate that with a sample of similar to 30 objects, are should be able to determine relative luminosity distances over the range 0 < z < 0.5 with sufficient precision to measure Omega(M) with an uncertainty of +/-0.2. C1 Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Weston, ACT 2611, Australia. Cerro Tololo Interamer Observ, La Serena, Chile. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. European So Observ, D-85748 Garching, Germany. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Univ Chile, Dept Astron, Santiago, Chile. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. RP Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Weston Creek PO, Weston, ACT 2611, Australia. RI Stubbs, Christopher/C-2829-2012; Maza, Jose/I-5722-2016; Hamuy, Mario/G-7541-2016; OI Stubbs, Christopher/0000-0003-0347-1724; Maza, Jose/0000-0003-2068-1328; Schmidt, Brian/0000-0001-6589-1287 NR 119 TC 909 Z9 917 U1 3 U2 21 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1998 VL 507 IS 1 BP 46 EP 63 DI 10.1086/306308 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LQ UT WOS:000077779400006 ER PT J AU Press, WH Rybicki, GB AF Press, WH Rybicki, GB TI Magnification ratio of the fluctuating light in gravitational lens 0957+561 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gravitational lensing; quasars : individual (0957+561) ID TIME-DELAY; VLBI OBSERVATIONS; STARS; A,B AB Radio observations establish the B/A magnification ratio of gravitational lens 0957+561 at about 0.75. Yet, for more than 15 years, the optical magnification ratio has been between 0.9 and 1.12. The accepted explanation is microlensing of the optical source. However, this explanation is mildly discordant with (1) the relative constancy of the optical ratio and (2) recent data indicating possible nonachromaticity in the ratio. To study these issues, we develop a statistical formalism for separately measuring, in a unified manner, the magnification ratio of the fluctuating and constant parts of the light curve. Applying the formalism to the recently published data of Kundic and coworkers, we find that the magnification ratios of fluctuating parts in both the g and, colors agrees with the magnification ratio of the constant part in g band, and tends to disagree with the r-band value. One explanation could be about 0.1 mag of consistently unsubtracted r light from the lensing galaxy G1, which seems unlikely. Another could be that 0957 + 561 is approaching a caustic in the microlensing pattern. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 17 TC 7 Z9 7 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1998 VL 507 IS 1 BP 108 EP 112 DI 10.1086/306322 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LQ UT WOS:000077779400010 ER PT J AU Patel, NA Goldsmith, PF Heyer, MH Snell, RL Pratap, P AF Patel, NA Goldsmith, PF Heyer, MH Snell, RL Pratap, P TI Origin and evolution of the Cepheus bubble SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : bubbles; ISM : individual (Cepheus bubble); ISM : molecules; open clusters and associations : individual (Cepheus OB2); radio lines : ISM ID MOLECULAR CLOUD COMPLEXES; OPEN CLUSTER TRUMPLER-37; O-STARS; GRAVITATIONAL INSTABILITIES; INTERSTELLAR-MEDIUM; COMETARY GLOBULES; MILKY-WAY; CO SURVEY; KINEMATICS; GALAXIES AB We have imaged a 10 degrees x 10 degrees region of the Cepheus bubble in the J = 1-0 line of CO and the 21 cm line of atomic hydrogen. The CO emission defines a giant expanding shell 120 pc in diameter, which is similar to that seen in the IRAS sky maps. We estimate the total gas mass in the region to be similar to 4 x 10(5) M.. The total kinetic energy from the observed spread of velocities of the molecular clouds is similar to 10(51) ergs. We suggest that the members of earlier generations of massive stars in NGC 7160 are responsible for the origin of the Cepheus bubble. These stars created an expanding compressed shell of gas that became gravitationally unstable at an age of similar to 7 Myr. The members of the Cepheus OB2 association comprise the second, intermediate generation of stars in this region that formed as a consequence of this instability. The numerous color selected IRAS point sources represent the third and youngest generation of stars in this region. Our observations suggest the great importance of sequentially triggered star formation in the region of the Cepheus bubble. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Cornell Univ, Natl Astron & Ionosphere Ctr, Dept Astron, Ithaca, NY 14853 USA. Univ Massachusetts, Five Coll Radio Astron Observ, Amherst, MA 01003 USA. MIT, Haystack Observ, Westford, MA 01886 USA. RP Patel, NA (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. EM npatel@cfa.harvard.edu RI Goldsmith, Paul/H-3159-2016 NR 58 TC 58 Z9 58 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1998 VL 507 IS 1 BP 241 EP 253 DI 10.1086/306305 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LQ UT WOS:000077779400023 ER PT J AU Warren, HP Mariska, JT Wilhelm, K AF Warren, HP Mariska, JT Wilhelm, K TI High-resolution observations of the solar hydrogen Lyman lines in the quiet sun with the sumer instrument on SOHO SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE line, profiles; sun, chromosphere; sun, UV radiation ID TRANSITION REGION; RADIOMETRIC CALIBRATION; ENERGY-BALANCE; O-VI; ALPHA; SPECTROMETER; TELESCOPE; SPECTRA; MODELS; WAVELENGTHS AB We present high-resolution observations of the higher H Lyman series lines taken with the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) experiment flown on the Solar and Heliospheric Observatory (SOHO) spacecraft. We have used systematic observations extending from disk center to the solar limb to compute average profiles for representative solar features of the quiet Sun, limb-brightening curves, and full-disk, quiet-Sun profiles for Ly beta through Ly lambda(11) and the Lyman continuum. The effects of radiative transfer are apparent in all of the line profiles we studied. The average quiet-Sun profiles for Ly beta through Ly epsilon are self-reversed, and the remaining lines are flat-topped The characteristics of the line profiles vary markedly with intensity. We observe strong enhancements in the red wings of network profiles, while the faint cell-center profiles are nearly symmetric. We also find that the intensities of the H Lyman lines increase at the limb, although the limb brightening is weak compared to optically thin transition region emission lines and largely obscured by the intensity variations observed in the quiet Sun. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. RP Warren, HP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 58, Cambridge, MA 02138 USA. EM hpw@dogwood.nrl.navy.mil NR 39 TC 67 Z9 68 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD NOV PY 1998 VL 119 IS 1 BP 105 EP 120 DI 10.1086/313151 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 139TU UT WOS:000077046400007 ER PT J AU Jennions, MD Backwell, PRY AF Jennions, MD Backwell, PRY TI Variation in courtship rate in the fiddler crab Uca annulipes: is it related to male attractiveness? SO BEHAVIORAL ECOLOGY LA English DT Article DE courtship; female choice; fiddler crabs; male choice; ornaments; sexual selection; Uca annulipes ID MALE MATE CHOICE; PREDATION RISK; HANDICAP PRINCIPLE; POECILIA-LATIPINNA; SEXUAL SELECTION; ADVERTISEMENT; COSTS AB We investigated among-male variation in courtship waving in the fiddler crab Uca annulipes. Wave rate is positively correlated with both male carapace size and relative claw size (controlled for body size), and relative claw size is positively correlated with an index of body condition. An experimental reduction in the availability of food decreased male wave rate. These data suggest that some of the variation in wave rate among males is due to variation in male condition combined with energetic costs to waving (differential costs). However, we also found that the correlation between male size and wave rate decreased over the semilunar cycle. Later in the cycle, smaller males increase their wave rate relative to that of larger males. Previous work has shown that females are more likely to accept a smaller male as a mate later in the cycle. We suggest that smaller males invest disproportionately more in courtship later in the cycle because the potential benefits are greater due to their increased attractiveness to females (differential benefits). Alternative explanations for the observed temporal trend are also discussed. C1 Univ Witwatersrand, Dept Zool, Commun Biol Res Grp, ZA-2050 Johannesburg, South Africa. Smithsonian Trop Res Inst, Panama City, Panama. RP Jennions, MD (reprint author), Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. RI Jennions, Michael/C-7560-2009; Backwell, Patricia/C-8883-2009 OI Jennions, Michael/0000-0001-9221-2788; NR 36 TC 53 Z9 55 U1 0 U2 8 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 NOV-DEC PY 1998 VL 9 IS 6 BP 605 EP 611 DI 10.1093/beheco/9.6.605 PG 7 WC Behavioral Sciences; Biology; Ecology; Zoology SC Behavioral Sciences; Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Zoology GA 167KF UT WOS:000078631200010 ER PT J AU Hagedorn, M Kleinhans, FW Artemov, D Pilatus, U AF Hagedorn, M Kleinhans, FW Artemov, D Pilatus, U TI Characterization of a major permeability barrier in the zebrafish embryo SO BIOLOGY OF REPRODUCTION LA English DT Article ID BRACHYDANIO-RERIO EMBRYOS; FISH EMBRYOS; CRYOPROTECTANT; DIMETHYLSULFOXIDE; MEMBRANE; WATER; SENSITIVITY; GLYCEROL; BEHAVIOR; OOCYTES AB Fish embryos represent a class of multicompartmental biological systems that have not been successfully cryopreserved, primarily because of the lack of understanding of how water and cryoprotectants permeate the compartments. We are using the zebrafish embryo as a model to understand these kinetics. Zebrafish embryos have two major compartments, the blastoderm and the yolk, which is surrounded by the multinucleated yolk syncytial layer (YSL). We determined the water and cryoprotectant permeability in these compartments using two methods. First, we measured shrink/swell dynamics in optical volumetric experiments. Zebrafish embryos shrank over time and did not re-expand while immersed in dimethyl sulfoxide (DMSO) or propylene glycol. Second, we measured DMSO uptake with diffusion-weighted nuclear magnetic resonance spectroscopy. DMSO uptake was rapid during the first few minutes, then gradual thereafter. We used one- and two-compartment models to analyze the data and to determine the permeability parameters. We found that the two-compartment model provided a better fit to the data. On the basis of this model and in the presence of DMSO, the yolk and blastoderm had very similar water permeabilities (i.e., 0.01 and 0.005 mu m x min(-1)atm(-1), respectively), but they had different DMSO permeabilities separated by three orders of magnitude (i.e., less than or equal to 5 x 10(-6) and 1.5 x 10(-3) cm/min, respectively). The low solute permeability of the yolk predicted that the yolk/YSL compartment should be more susceptible to cryodamage. To test this, the yolk, blastoderm, and YSL were examined at the ultrastructural level after vitrification. Only the YSL incurred significant damage after freezing and thawing (p less than or equal to 0.05). C1 Smithsonian Inst, Natl Zool Pk, Reprod Physiol Program, Washington, DC 20008 USA. IUPUI, Dept Phys, Indianapolis, IN 46202 USA. Johns Hopkins Univ, Sch Med, Dept Radiol, Baltimore, MD 21205 USA. RP Hagedorn, M (reprint author), Smithsonian Inst, Natl Zool Pk, Reprod Physiol Program, 3001 Conn Ave NW, Washington, DC 20008 USA. EM mhagedorn@nzp.si.edu FU NCRR NIH HHS [R29 RR08769] NR 26 TC 66 Z9 74 U1 0 U2 7 PU SOC STUDY REPRODUCTION PI MADISON PA 1603 MONROE ST, MADISON, WI 53711-2021 USA SN 0006-3363 J9 BIOL REPROD JI Biol. Reprod. PD NOV PY 1998 VL 59 IS 5 BP 1240 EP 1250 DI 10.1095/biolreprod59.5.1240 PG 11 WC Reproductive Biology SC Reproductive Biology GA 133FP UT WOS:000076676400030 PM 9780333 ER PT J AU Child, CA AF Child, CA TI Nymphon torulum, new species and other pycnogonida associated with the coral Oculina varicosa on the east coast of Florida SO BULLETIN OF MARINE SCIENCE LA English DT Article AB Eighty-eight identified pycnogonid specimens belonging to 15 species of 11 genera in six families were found associated with the coral Oculina varicosa Lesueur off the east coast of Florida. One new species, Nymphon torulum, is fully described, illustrated and compared with its congeners. Distribution is given for all 15 species along with pertinent remarks, except for several juvenile or damaged specimens assigned to genus only. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Child, CA (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 37 TC 5 Z9 6 U1 0 U2 1 PU ROSENSTIEL SCH MAR ATMOS SCI PI MIAMI PA 4600 RICKENBACKER CAUSEWAY, MIAMI, FL 33149 USA SN 0007-4977 J9 B MAR SCI JI Bull. Mar. Sci. PD NOV PY 1998 VL 63 IS 3 BP 595 EP 604 PG 10 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 163LR UT WOS:000078407600013 ER PT J AU Banaszak, AT Lesser, MP Kuffner, IB Ondrusek, M AF Banaszak, AT Lesser, MP Kuffner, IB Ondrusek, M TI Relationship between ultraviolet (UV) radiation and mycosporine-like amino acids (MAAS) in marine organisms SO BULLETIN OF MARINE SCIENCE LA English DT Article ID URCHIN STRONGYLOCENTROTUS-DROEBACHIENSIS; ABSORBING COMPOUNDS; WATER MOTION; CORAL; GREEN; REEF; QUANTITATION; PROTECTION; PROTEIN AB Although only about 5-7% of solar radiation reaching the earth's surface is composed of UV-A (320-400 nm) and UV-B (286-320 nm), the biological significance of these wavelengths is disproportionate due to the higher energy content of quanta in the UV compared to the visible portion of the spectrum (Moseley, 1988). Exposure of shallow-water benthic organisms to high fluxes of solar irradiance requires a trade-off between maintaining high rates of photosynthesis while preventing damage from UV radiation. Biochemical defenses against the effects of UV may include the presence of mycosporine-like amino acids (MAAs) (Dunlap and Shick, 1998 and refs therein). These compounds have been found in a variety of marine organisms spanning from cyanobacteria (Shibata, 1959) to teleosts (Dunlap et al., 1989) and from tropical (Dunlap et al., 1986) to Antarctic waters (Karentz et al., 1991). Some tropical and temperate open ocean waters have low attenuation coefficients of UV and photosynthetically active radiation (PAR, 400-700 nm) due to the low levels of particulates and humic substances which absorb or scatter these wavelengths (Kirk, 1994). In other waters, such as around mangroves and estuaries, dissolved organic matter or gilvin and particulates decrease the transparency of the water column resulting in reduced penetration of PAR and even greater reduction of UV with increasing depth (Kirk, 1994). The purpose of this study was to survey for the presence of MAAs in macrophytes and invertebrates from habitats differing in water quality to determine the relationship between the concentration of these compounds and incident UV radiation. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Univ New Hampshire, Dept Zool, Durham, NH 03824 USA. Ctr Marine Biol, Durham, NH 03824 USA. Univ Hawaii, Hawaii Inst Marine Biol, Kaneohe Bay, HI 96744 USA. Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Honolulu, HI 96822 USA. RP Banaszak, AT (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. EM banazak@serc.si.edu; mpl@christa.unh.edu; ilsak@hawaii.edu; ondrusek@soest.hawaii.edu RI Kuffner, Ilsa/A-6416-2008; Ondrusek, Michael/F-5617-2010; OI Ondrusek, Michael/0000-0002-5311-9094; Kuffner, Ilsa/0000-0001-8804-7847 NR 24 TC 59 Z9 63 U1 0 U2 6 PU ROSENSTIEL SCH MAR ATMOS SCI PI MIAMI PA 4600 RICKENBACKER CAUSEWAY, MIAMI, FL 33149 USA SN 0007-4977 J9 B MAR SCI JI Bull. Mar. Sci. PD NOV PY 1998 VL 63 IS 3 BP 617 EP 628 PG 12 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 163LR UT WOS:000078407600016 ER PT J AU Winker, K AF Winker, K TI Recent geographic trends in Neotropical avian research SO CONDOR LA English DT Editorial Material DE avian research; biodiversity; conservation; Neotropics ID ORNITHOLOGY AB Knowledge-based conservation efforts have a greater chance of success than efforts without a sound scientific basis. The geographic distribution of Neotropical ornithological studies published from 1979-1995 is very uneven. Land and human population characteristics, considered an index of threat to a country's avifauna, are not correlated with recent Neotropical avian research efforts. When these statistics are examined in conjunction with publication levels and species richness, three groups of countries are distinguished. The most neglected group of countries (Group 1) have a combination of lower numbers of bird species and publications, yet have high population densities and a high percentage of domesticated lands. A subset of Central American countries is of particular concern for its importance to wintering Nearctic-Neotropic migrants. I suggest that efforts be made to improve research coverage and quality, particularly among Group 1 countries. C1 Smithsonian Inst, Natl Museum Nat Hist, Div Birds, Washington, DC 20560 USA. Univ Alaska Museum, Fairbanks, AK 99775 USA. Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Winker, K (reprint author), Univ Alaska Museum, 907 Yukon Dr, Fairbanks, AK 99775 USA. RI Winker, Kevin/M-2042-2014 OI Winker, Kevin/0000-0002-8985-8104 NR 9 TC 9 Z9 11 U1 0 U2 3 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0010-5422 J9 CONDOR JI Condor PD NOV PY 1998 VL 100 IS 4 BP 764 EP 768 DI 10.2307/1369763 PG 5 WC Ornithology SC Zoology GA 137CM UT WOS:000076897100023 ER PT J AU Ivanova, NV DePriest, PT Bobrova, VK Troitskii, AV AF Ivanova, NV DePriest, PT Bobrova, VK Troitskii, AV TI Group I introns in the fungal 18S rDNA of the lichen family Umbilicariaceae SO DOKLADY AKADEMII NAUK LA Russian DT Article ID RIBOSOMAL-RNA GENE; SSU RDNA; PCR PRIMERS; INSERTION; DNA C1 AN Belozerskii Phys Chem Biol Inst, Moscow, Russia. Smithsonian Inst, Washington, DC 20560 USA. RP Ivanova, NV (reprint author), AN Belozerskii Phys Chem Biol Inst, Moscow, Russia. RI DePriest, Paula/K-6633-2015 NR 14 TC 3 Z9 3 U1 0 U2 0 PU MEZHDUNARODNAYA KNIGA PI MOSCOW PA 39 DIMITROVA UL., 113095 MOSCOW, RUSSIA SN 0869-5652 J9 DOKL AKAD NAUK+ JI Dokl. Akad. Nauk PD NOV PY 1998 VL 363 IS 3 BP 400 EP 404 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 157LQ UT WOS:000078063700031 PM 9891211 ER PT J AU Weller, DE Jordan, TE Correll, DL AF Weller, DE Jordan, TE Correll, DL TI Heuristic models for material discharge from landscapes with riparian buffers SO ECOLOGICAL APPLICATIONS LA English DT Article DE grid cell; landscape ecology; landscape index; model; nonpoint source pollution; nutrient discharge; raster; riparian buffer; riparian management scaling; sediment discharge; water quality ID WATER-QUALITY; LAND-USE; AGRICULTURAL WATERSHEDS; GEOGRAPHIC INFORMATION; SPATIAL PATTERN; COASTAL-PLAIN; NUTRIENT; GROUNDWATER; NITRATE; POLLUTION AB For landscapes with riparian buffers, we develop and analyze models predicting landscape discharge based on material release by an uphill source area, the spatial distribution of riparian buffer along a stream, and retention within the buffer. We model the buffer as a grid of cells, and each cell transmits a fixed fraction of the materials it receives. We consider the effects of variation in buffer width and buffer continuity, quantify the relative contributions of source elimination and buffer retention to total discharge reduction, and develop statistical relationships to simplify and generalize the models. Width variability reduces total buffer retention, increases the width needed to meet a management goal, and changes the importance of buffer retention relative to source elimination. Variable-width buffers are less efficient than uniform-width buffers because transport through areas of below-average buffer width (particularly gaps) dominates landscape discharge, especially for narrow buffers of highly retentive cells. Uniform-width models overestimate retention, so width variability should be considered when testing for buffer effects or designing buffers for water quality management. Adding riparian buffer to a landscape can decrease material discharge by increasing buffer retention and by eliminating sourer areas. Source elimination is more important in unretentive or wide buffers, while buffer retention dominates in narrow, retentive buffers. We summarize model results with simpler statistical relationships. For unretentive buffers, average width is the best predictor of landscape discharge, while the frequency of gaps was best for narrow, retentive buffers. Together, both predictors explain >90% of the variance in average landscape transmission for any value of buffer retentiveness. We relate our results to ecological theory, landscape-scale buffer eaters, buffer management, and water quality models. We recommend more empirical studies of buffer width variability and its effects on material discharge. Landscape models should represent width variability and the nonlinear interactions between buffers and source areas. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Weller, DE (reprint author), Smithsonian Environm Res Ctr, POB 28,647 Contees Wharf Rd, Edgewater, MD 21037 USA. OI Weller, Donald/0000-0002-7629-5437 NR 73 TC 66 Z9 73 U1 0 U2 14 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 USA SN 1051-0761 J9 ECOL APPL JI Ecol. Appl. PD NOV PY 1998 VL 8 IS 4 BP 1156 EP 1169 DI 10.2307/2640969 PG 14 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA 141EL UT WOS:000077129600020 ER PT J AU Ruffin, KK AF Ruffin, KK TI The persistence of anthropogenic turbidity plumes in a shallow water estuary SO ESTUARINE COASTAL AND SHELF SCIENCE LA English DT Article DE turbidity; light attenuation; dredging; suspended sediments; SAV; Chesapeake Bay ID SEDIMENT RESUSPENSION; AQUATIC VEGETATION; CHESAPEAKE BAY; LIGHT; COMMUNITIES AB Increased turbidity and light attenuation (K-d) in the suspended sediment plumes created by hydraulic clam dredging were examined in Chesapeake Bay, MD, U.S.A. Turbidity and K-d values were measured along transects in areas with and without dredge plumes. The turbidity and K-d of individual plumes were tracked as they returned to background levels using both Lagrangian and Eulerian techniques. Existing aerial photographs and a geographical information system (ARC/INFO) were used to examine plume sizes and dredge boat locations in relation to bathymetry. Hydraulic clam dredging produced plumes with significantly higher turbidity and light attenuation compared to background values. Plume characteristics were determined primarily by bottom sediment type and water depth. The greatest increase in turbidity and light attenuation occurred when dredges operated in shallow water (<1.0 m) where bottom sediments had increased amounts of silt and clay. Plume turbidity and K-d dissipated exponentially over time. The initial change in concentration of suspended sediments was rapid as the coarse sediments settled to the bottom. The rate of plume decay slowed as diffusion and resuspension acted on the finer sediments remaining in suspension. Some Lagrangian rates of plume dissipation were faster than Eulerian rates due to resuspension in shallow waters. Examination of aerial photographs indicated that 72% of the dredge boats digitized in the Chester River were operating in less than 2 m water. The area of a plume measured per boat in the Chester River was highly variable, ranging from 0.01 to 0.64 m(2). (C) 1998 Academic Press. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Ruffin, KK (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. NR 28 TC 25 Z9 25 U1 1 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0272-7714 J9 ESTUAR COAST SHELF S JI Estuar. Coast. Shelf Sci. PD NOV PY 1998 VL 47 IS 5 BP 579 EP 592 DI 10.1006/ecss.1998.0366 PG 14 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 139FX UT WOS:000077018300004 ER PT J AU Tabacchi, E Correll, DL Hauer, R Pinay, G Planty-Tabacchi, AM Wissmar, RC AF Tabacchi, E Correll, DL Hauer, R Pinay, G Planty-Tabacchi, AM Wissmar, RC TI Development, maintenance and role of riparian vegetation in the river landscape SO FRESHWATER BIOLOGY LA English DT Article; Proceedings Paper CT Workshop on River in the Landscape: Riparian and Groundwater Ecology CY FEB 05-11, 1996 CL SWISS FED INST ENVIRONM SCI & TECHNOL, KASTANIENBAUM, SWITZERLAND HO SWISS FED INST ENVIRONM SCI & TECHNOL DE riparian zone; plant ecology; rivers; streams; ecosystems; groundwater ID PARTICULATE ORGANIC-MATTER; PLANT-SPECIES RICHNESS; ECOSYSTEM PERSPECTIVE; STREAM TEMPERATURE; NITROGEN-RETENTION; FORESTED WETLAND; WATER-QUALITY; ADOUR RIVER; DYNAMICS; COMMUNITIES AB 1. Riparian structure and function were considered from a longitudinal perspective in order to identify multiscale couplings with adjacent ecosystems and to identify research needs. 2. We characterized functional zones (with respect to vegetation development in association with various biogeochemical processes) within geomorphological settings using a delineation based upon erosional, transitional and depositional properties. 3. Vegetation dynamics within the riparian corridor are clearly influenced substantially by hydrological disturbance regimes. In turn, we suggest that vegetation productivity and diversity may widely influence riverine biogeochemical processes, especially as related to the consequences of changing redox conditions occurring from upstream to downstream. 4. However, surface and groundwater linkages are the predominant controls of landscape connectivity within riparian systems. 5. The importance of riparian zones as sources and sinks of matter and energy was examined in context of structural and functional attributes, such as sequestering or cycling of nutrients in sediments, retention of water in vegetation, and retention, diffusion or dispersal of biota. 6. The consequences of interactions between different communities (e.g. animals and plants, micro-organisms and plants) on biogeochemical processes are notably in need of research, especially with respect to control of landscape features. Multiscale approaches, coupling regional and local factors in all three spatial dimensions, are needed in order to understand more synthetically and to model biogeochemical and community processes within the river-riparian-upland landscape of catchments. C1 Ctr Ecol Syst Aquat Continentaux, UMR C5576, F-31055 Toulouse 04, France. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Univ Montana, Flathead Lake Biol Stn, Polson, MT 59860 USA. Univ Rennes 1, ECOBIO, UMR 6553, F-35042 Rennes, France. Univ Washington, Coll Ocean & Fisheries Sci, Seattle, WA 98195 USA. RP Tabacchi, E (reprint author), Ctr Ecol Syst Aquat Continentaux, UMR C5576, 29 Rue Jeanne Marvig, F-31055 Toulouse 04, France. EM tabacchi@cesac.cemes.fr NR 143 TC 199 Z9 215 U1 9 U2 93 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 NOV PY 1998 VL 40 IS 3 BP 497 EP 516 DI 10.1046/j.1365-2427.1998.00381.x PG 20 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 153YH UT WOS:000077860800006 ER PT J AU Watters, TR Robinson, MS Cook, AC AF Watters, TR Robinson, MS Cook, AC TI Topography of lobate scarps on Mercury: New constraints on the planet's contraction SO GEOLOGY LA English DT Article ID DISPLACEMENT; LINKAGE; FAULTS; MARS; MOUNTAINS; GROWTH; STRAIN; RIDGES; RADAR AB Lobate scarps are landforms on Mercury that appear to have formed by thrust faulting and are thought to reflect global contraction due to cooling of the planet's interior. Topographic data for 10 mercurian lobate scarps, derived from Mariner 10 images using photoclinometry and digital stereoanalysis, indicate a range in maximum relief of 0.1 to 1.5 km and a range in horizontal shortening of 0.3 to 3.2 km, assuming fault-plane dips (theta) of 25 degrees. Previous estimates of cumulative compressional strain recorded in the lobate scarps suggest a decrease in Mercury's radius of 1 to 2 km. Our estimate of compressional strain based on these new topographic measurements is similar to 0.056% (theta = 25 degrees). This suggests that Mercury's radius decreased by <1 km. C1 Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. Northwestern Univ, Dept Geol Sci, Evanston, IL 60208 USA. RP Watters, TR (reprint author), Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. NR 44 TC 66 Z9 66 U1 0 U2 3 PU ASSOC ENGINEERING GEOLOGISTS GEOLOGICAL SOCIETY AMER PI COLLEGE STN PA TEXAS A & M UNIV, DEPT GEOLOGY & GEOPHYSICS, COLLEGE STN, TX 77843-3115 USA SN 0091-7613 J9 GEOLOGY JI Geology PD NOV PY 1998 VL 26 IS 11 BP 991 EP 994 DI 10.1130/0091-7613(1998)026<0991:TOLSOM>2.3.CO;2 PG 4 WC Geology SC Geology GA 135MX UT WOS:000076807000008 ER PT J AU Reinhardt, EG Stanley, DJ Patterson, RT AF Reinhardt, EG Stanley, DJ Patterson, RT TI Strontium isotopic-paleontological method as a high-resolution paleosalinity tool for lagoonal environments SO GEOLOGY LA English DT Article ID NILE DELTA; MARINE; WATER; STRATIGRAPHY; MISSISSIPPI; SR-87/SR-86; VERTEBRATE; SEDIMENTS; INDICATOR; FRESH AB A combined strontium isotopic (Sr-87/Sr-86) and paleontological method is newly applied to a modern lagoon in Egypt's Nile River delta to test its applicability as a paleosalinity proxy. Analyses of 22 surficial samples collected throughout the lagoon include 81 Sr isotopic analyses of mollusks, foraminifera, ostracods, barnacles, bryozoans, serpulid worm tubes, pore water, and gypsum crystals. Two salinity groups are distinguished in each sample: a lower salinity group (similar to 1 ppt) mixed with a higher salinity group (similar to 3-10 ppt) that, respectively, are interpreted as the modern biocoenosis and an older relict fauna. The relict fauna denotes higher salinity conditions in the lagoon prior to closure of the Aswan High Dam (1964), and the modern fauna records freshening of the lagoon. Recent decreased salinity is a response to regulated Nile River flow and increased discharge into Manzala of fresh water via canals and drains. Quantification of this short-term salinity change holds promise for study of modern lagoons in other world settings, and may provide paleoclimatic information for older lagoon sequences in the Nile River delta and the geologic record. C1 Dalhousie Univ, Dept Earth Sci, Halifax, NS B3H 3J5, Canada. Smithsonian Inst, Deltas Global Change Program, Washington, DC 20560 USA. Carleton Univ, Dept Earth Sci, Ottawa, ON K1S 5B6, Canada. RP Reinhardt, EG (reprint author), Dalhousie Univ, Dept Earth Sci, Halifax, NS B3H 3J5, Canada. NR 22 TC 22 Z9 25 U1 1 U2 4 PU ASSOC ENGINEERING GEOLOGISTS GEOLOGICAL SOCIETY AMER PI COLLEGE STN PA TEXAS A & M UNIV, DEPT GEOLOGY & GEOPHYSICS, COLLEGE STN, TX 77843-3115 USA SN 0091-7613 J9 GEOLOGY JI Geology PD NOV PY 1998 VL 26 IS 11 BP 1003 EP 1006 DI 10.1130/0091-7613(1998)026<1003:SIPMAA>2.3.CO;2 PG 4 WC Geology SC Geology GA 135MX UT WOS:000076807000011 ER PT J AU Jucks, KW Johnson, DG Chance, KV Traub, WA Margitan, JJ Osterman, GB Salawitch, RJ Sasano, Y AF Jucks, KW Johnson, DG Chance, KV Traub, WA Margitan, JJ Osterman, GB Salawitch, RJ Sasano, Y TI Observations of OH, HO2, H2O, and O-3 in the upper stratosphere: implications for HOx photochemistry SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID OZONE AB Balloon-borne observations of concentrations of OH, HO2, H2O, and O-3 in the middle and upper stratosphere are used to test our understanding of HOx photochemistry. Assuming our photochemical model is complete, the measured [OH] and [HO2] above 38 km (where HOx partitioning is no longer dependent on [NO]) are modeled best by calculations that use a 25% reduction in the ratio of the reaction rate constants for O+HO2 and O+OH as well as either a 25% reduction Of the rate constant of OH+HO2 (the primary HOx sink) or a 25% increase in HOx production. All of these changes are consistent with the uncertainties in the recommended rate constants. The kinetic parameters required to explain our observations of [OH] and [HO2] do not lead to a resolution of the long-standing "ozone deficit problem" above 45 km. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Japan Environm Agcy, Natl Inst Environm Studies, Ibaraki 305, Japan. RP Jucks, KW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Salawitch, Ross/B-4605-2009; Sasano, Yasuhiro/C-2927-2009; Johnson, David/F-2376-2015; OI Salawitch, Ross/0000-0001-8597-5832; Sasano, Yasuhiro/0000-0001-7470-5642; Johnson, David/0000-0003-4399-5653; Chance, Kelly/0000-0002-7339-7577 NR 11 TC 60 Z9 61 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 NOV 1 PY 1998 VL 25 IS 21 BP 3935 EP 3938 DI 10.1029/1998GL900009 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 136CE UT WOS:000076839800005 ER PT J AU Pukazhenthi, BS Long, JA Wildt, DE Ottinger, MA Armstrong, DL Howard, J AF Pukazhenthi, BS Long, JA Wildt, DE Ottinger, MA Armstrong, DL Howard, J TI Regulation of sperm function by protein tyrosine phosphorylation in diverse wild Felid species SO JOURNAL OF ANDROLOGY LA English DT Article DE cat; cAMP; capacitation ID LAPAROSCOPIC ARTIFICIAL-INSEMINATION; TERATOSPERMIC DOMESTIC CATS; TIGER PANTHERA-TIGRIS; ZONA-PELLUCIDA; ACROSOME REACTION; EXOGENOUS GONADOTROPINS; MOUSE SPERMATOZOA; GAMETE INTERACTION; CLOUDED LEOPARD; CALCIUM INFLUX AB Protein tyrosine phosphorylation is associated with sperm capacitation and the acrosome reaction in several mammalian species. Changes in phosphorylation of a 95-kDa protein in human, mouse, and domestic cat spermatozoa are known to be influenced by capacitation and exposure to zona pellucida (ZP) proteins. We previously reported diminished phosphorylation of 95- and 160-kDa proteins in spermatozoa from teratospermic cats, compared with normospermic domestic cats. To determine if these proteins and mechanisms are present in other species in the phenotypically diverse Felidae family, we examined the relationship between tyrosine-phosphorylated sperm proteins and sperm morphology in the leopard cat (similar to 65% normal sperm/ejaculate), tiger (similar to 65%), clouded leopard (similar to 15%), and cheetah (similar to 30%). Furthermore, we investigated the involvement of cyclic adenosine monophosphate (cAMP) in the regulation of sperm protein tyrosine phosphorylation. Specifically, we assessed the following: 1) presence of tyrosine-phosphorylated proteins in sperm extracts; 2) changes in protein tyrosine phosphorylation after sperm capacitation and swim-up separation; 3) impact of tyrosine kinase inhibition on leopard cat sperm protein phosphorylation and ZP penetration; and 4) involvement of a cAMP-dependent pathway in the regulation of protein tyrosine phosphorylation. Immunoblotting analysis with anti-phosphotyrosine antibody (PY20) indicated that a 95-kDa protein was present in all four species. Additional phosphorylated proteins were detected in the leopard cat (145- and 175-kDa proteins), tiger (185-kDa protein), clouded leopard (160- and 190-kDa proteins), and cheetah (115- and 155-kDa proteins). Sperm capacitation in vitro increased phosphorylation of one or more proteins in the leopard cat, tiger and clouded leopard, but not in the cheetah. Although swim-up separation increased the proportion of morphologically normal spermatozoa in the clouded leopard and cheetah, no changes were observed in phosphorylation of the 95-kDa sperm protein. Thus, phosphorylation of the 95-kDa protein appeared to be related to the condition of teratospermia. Exposing leopard cat spermatozoa to the tyrosine kinase inhibitor, tyrphostin, reduced (P < 0.05) phosphorylation of the 95- and 145-kDa proteins, as well as ZP penetration, without affecting sperm motility. Similarly, when spermatozoa were incubated in the presence of cAMP analogs or active and inactive stereoisomers of cAMP, phosphorylation of sperm proteins was either stimulated or inhibited. Together, these data suggest that protein tyrosine kinase mechanisms appear conserved within the family Felidae and are regulated by a cAMP/protein kinase A pathway. C1 Smithsonian Inst, Natl Zool Pk, Reprod Physiol Program, Washington, DC 20008 USA. Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA USA. Henry Doorly Zoo, Omaha, NE USA. Univ Maryland, College Pk, MD 20742 USA. RP Smithsonian Inst, Natl Zool Pk, Reprod Physiol Program, Washington, DC 20008 USA. FU NICHD NIH HHS [HD-23853] NR 53 TC 31 Z9 32 U1 1 U2 9 PU AMER SOC ANDROLOGY, INC PI LAWRENCE PA C/O ALLEN PRESS, INC PO BOX 368, LAWRENCE, KS 66044 USA SN 0196-3635 EI 1939-4640 J9 J ANDROL JI J. Androl. PD NOV-DEC PY 1998 VL 19 IS 6 BP 675 EP 685 PG 11 WC Andrology SC Endocrinology & Metabolism GA 149LD UT WOS:000077606000005 PM 9876019 ER PT J AU Ohtsuka, S Reid, JW AF Ohtsuka, S Reid, JW TI Phylogeny and zoogeography of the planktonic copepod genus Tortanus (Calanoida : Tortanidae), with establishment of a new subgenus and descriptions of two new species SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article ID SEA-BOTTOM MUDS; DISCAUDATUS; ZOOPLANKTON; PREDATION; BEHAVIOR; OCEAN; EGGS AB Tortanus (Boreotortanus), new subgenus, is established to accommodate the North Pacific/northwestern Atlantic species T, discaudatus and the taxonomy and ecology of the five subgenera in the genus Tortanus are discussed. Tortanus sensu stricto occurs in eutrophic waters in the Indo-West Pacific, Atortus in oligotrophic waters in the same region, Eurortanus in brackish waters in East Asia, Acutanus in eutrophic waters in the northwestern Atlantic, and Boreotortanus in eutrophic waters in the North Pacific and the northwestern Atlantic. Two new species are described: T. (Eutortanus) terminalis and T (Acutanus) ecornatus. Phylogenetic relationships among the 5 subgenera were constructed based on cladistic and zoogeographical analyses. Boreotortanus may have originated in the Sea of Japan; Eutortanus in the East China Sea; Tortanus sensu stricto in the Indo-Malayan region. The final divergence is represented by the Atortus-Acutanus clade, which is characterized by reductions of elements on the antennule, the antenna, legs 2 and 3 of both sexes, and elongation of the left leg 5 of males. The ancestor of Acutanus could have colonized the northwestern Atlantic from the Indo-Malayan region through the Isthmus of Panama during the Middle Miocene to Pliocene. It appears that Atortus first succeeded in exploiting clear oligotrophic waters and in developing swarming behavior to avoid visual predators in such clear waters. These originally tropical copepods seem to have secondarily adapted to cold waters along the East Asian archipelagoes during the Pleistocene. C1 Hiroshima Univ, Fisheries Lab, Hiroshima 7250024, Japan. Smithsonian Inst, Natl Museum Amer Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Ohtsuka, S (reprint author), Hiroshima Univ, Fisheries Lab, 5-8-1 Minato Machi, Hiroshima 7250024, Japan. NR 83 TC 15 Z9 17 U1 0 U2 3 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 NOV PY 1998 VL 18 IS 4 BP 774 EP 807 DI 10.2307/1549154 PG 34 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 137ER UT WOS:000076902300018 ER PT J AU Kharchenko, V Liu, WH Dalgarno, A AF Kharchenko, V Liu, WH Dalgarno, A TI X ray and EUV emission spectra of oxygen ions precipitating into the Jovian atmosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ELECTRON-CAPTURE; HEAVY-IONS; JUPITER; COLLISIONS AB Spectra of soft X ray and EUV emissions of oxygen ions, precipitating into the Jovian atmosphere, are calculated, taking into account the dynamical evolution of the energy and charge distributions of the ions as they propagate. Monte Carlo simulations are performed using experimental and theoretical cross sections of ion collisions with the atmospheric gases. The numbers of X ray and EUV photons produced per precipitating oxygen ion are calculated as functions of the initial ion energy and charge. The energy and charge distribution functions are used to evaluate the intensities of characteristic X ray and EUV emission lines of oxygen ions in Jovian auroras. Radiative cascade transitions from highly excited ion states are shown to be an important source mechanism of soft X ray and ultraviolet emission Lines. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Kharchenko, V (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM vkharchenko@cfa.harvard.edu NR 23 TC 38 Z9 38 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 NOV 1 PY 1998 VL 103 IS A11 BP 26687 EP 26698 DI 10.1029/98JA02395 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 133UX UT WOS:000076705500040 ER PT J AU Chen, W Grabow, JU Travers, MJ Munrow, MR Novick, SE McCarthy, MC Thaddeus, P AF Chen, W Grabow, JU Travers, MJ Munrow, MR Novick, SE McCarthy, MC Thaddeus, P TI Microwave spectra of the methylcyanopolyynes CH3(C C)(n)CN, n = 2, 3, 4, 5 SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID LABORATORY DETECTION; MOLECULAR-BEAM; SPECTROMETER; METHYLCYANOACETYLENE; SPECTROSCOPY; HC11N AB The ground state rotational spectra of four methylcyanopolyynes CH3(C=C)(2)CN, CH3(C=C)(3)CN, CH3(C=C)(4)CN, and CH3(C=C)(5)CN were measured between 6 and 22 GHz by Fourier transform microwave spectroscopy. For CH3(C=C)(2)CN, previously observed by Alexander et al. [J. Mol. Spectrosc. 70, 84-44 (1978)] eight transitions were observed, each with sufficient resolution to determine the nitrogen quadrupole hyperfine constant for the first time: eqQ = -4.25(3) MHz. The longer three methylcyanopolyynes are new, for these, from 10 to 21 rotational transitions were detected and precise values for the rotational and the leading centrifugal distortion constants, and eqQ for CH3(C=C)(3)CN, were determined. (C) 1998 Academic Press. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Wesleyan Univ, Dept Chem, Middletown, CT 06459 USA. RP Chen, W (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI McCarthy, Michael/0000-0001-9142-0008 NR 24 TC 11 Z9 11 U1 0 U2 5 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD NOV PY 1998 VL 192 IS 1 BP 1 EP 11 DI 10.1006/jmsp.1998.7665 PG 11 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 136NM UT WOS:000076865700001 ER PT J AU Travers, MJ Chen, W Grabow, JU McCarthy, MC Thaddeus, P AF Travers, MJ Chen, W Grabow, JU McCarthy, MC Thaddeus, P TI Microwave spectra of the methylpolyynes CH3(C C)(4)H and CH3(C C)(5)H SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID SPECTROMETER; MOLECULES AB Following the laboratory detection by Fourier transform microwave spectroscopy of the four new methylcyanopolyynes described in the accompanying paper by W. Chen et al. (J. Mol. Spectrosc. 1998), we detected two new methylpolyynes, CH3(C=C)(4)H and CH3(C=C)(5)H. The strongest lines of both molecules, obtained in a discharge with a dilute mixture of methylacetylene and diacetylene in neon, were quite intense: after 4 min of integration, a signal to noise of about 300 for the strongest Lines of CH3(C=C)(4)H and 30 for those of CH3(C=C)(5)H. Enough rotational transitions tkom the K = 0 and 1 ladders were detected in either molecule to be confident of the identification and to determine the rotational and leading centrifugal distortion constants to high accuracy. Like other carbon chains, the two here may be important in combustion processes and may be detectable in the interstellar gas, where the two shortest methylpolyynes have already been observed. (C) 1998 Academic Press. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP Travers, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI McCarthy, Michael/0000-0001-9142-0008 NR 19 TC 9 Z9 9 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD NOV PY 1998 VL 192 IS 1 BP 12 EP 16 DI 10.1006/jmsp.1998.7666 PG 5 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 136NM UT WOS:000076865700002 ER PT J AU Rothman, LS Rinsland, CP Goldman, A Massie, ST Edwards, DP Flaud, JM Perrin, A Camy-Peyret, C Dana, V Mandin, JY Schroeder, J McCann, A Gamache, RR Wattson, RB Yoshino, K Chance, KV Jucks, KW Brown, LR Nemtchinov, V Varanasi, P AF Rothman, LS Rinsland, CP Goldman, A Massie, ST Edwards, DP Flaud, JM Perrin, A Camy-Peyret, C Dana, V Mandin, JY Schroeder, J McCann, A Gamache, RR Wattson, RB Yoshino, K Chance, KV Jucks, KW Brown, LR Nemtchinov, V Varanasi, P TI The HITRAN molecular spectroscopic database and HAWKS (HITRAN Atmospheric Workstation): 1996 edition SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Review ID ABSORPTION CROSS-SECTIONS; COLLISION-INDUCED ABSORPTION; FAR-INFRARED SPECTRUM; SCHUMANN-RUNGE BANDS; NONLOCAL THERMODYNAMIC-EQUILIBRIUM; FOURIER-TRANSFORM SPECTROSCOPY; HIGH-RESOLUTION SPECTROSCOPY; AIR-BROADENING COEFFICIENTS; 720-NM WAVELENGTH REGION; DIODE-LASER SPECTROSCOPY AB Since its first publication in 1973, the HITRAN molecular spectroscopic database has been recognized as the international standard for providing the necessary fundamental spectroscopic parameters for diverse atmospheric and laboratory transmission and radiance calculations. There have been periodic editions of HITRAN over the past decades as the database has been expanded and improved with respect to the molecular species and spectral range covered, the number of parameters included, and the accuracy of this information. The 1996 edition not only includes the customary line-by-line transition parameters familiar to HITRAN users, but also cross-section data, aerosol indices of refraction, software to filter and manipulate the data, and documentation. This paper describes the data and features that have been added or replaced since the previous edition of HITRAN. We also cite instances of critical data that are forthcoming. Published by Elsevier Science Ltd. C1 VSBM, AF Res Lab, Bedford, MA 01731 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Langley Res Ctr, Div Atmospher Sci, Hampton, VA 23681 USA. Univ Denver, Dept Phys, Denver, CO 80208 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Paris 11, Photophys Mol Lab, CNRS, F-91405 Orsay, France. Univ Paris 06, LPMA, F-75252 Paris 05, France. Ontar Corp, N Andover, MA 01845 USA. Univ Lowell, Dept Environm Earth & Atmospher Sci, Lowell, MA 01854 USA. Utah State Univ, Stewart Radiance Lab, Bedford, MA 01730 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. RP Rothman, LS (reprint author), VSBM, AF Res Lab, 29 Randolph Rd, Bedford, MA 01731 USA. OI Chance, Kelly/0000-0002-7339-7577; Rothman, Laurence/0000-0002-3837-4847 NR 291 TC 1556 Z9 1597 U1 9 U2 81 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 NOV PY 1998 VL 60 IS 5 BP 665 EP 710 DI 10.1016/S0022-4073(98)00078-8 PG 46 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 129YR UT WOS:000076492100002 ER PT J AU Goldman, A Chance, KV Coffey, MT Hannigan, JW Mankin, WG Rinsland, CP AF Goldman, A Chance, KV Coffey, MT Hannigan, JW Mankin, WG Rinsland, CP TI Improved line parameters for the X-1 Sigma(+) (0-0) and (0-1) bands of HI SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID HIGH-RESOLUTION MEASUREMENTS; METHYL-IODIDE; OZONE; TRANSITIONS; EMISSIONS; SPECTRUM; REGION; OCEAN; SEAS AB Hyperfine lines associated with the X(1)Sigma(+) (0-0) and (0-1) bands of (HI)-I-127 are generated. Discussion of the HI line parameters in the HITRAN and SAO databases is presented. The new (0-0) line parameters are based on previously published far-infrared constants. High-resolution laboratory spectra in the infrared fundamental band region are presented and analyzed for new fine structure spectroscopic constants, which are combined with available hyperfine structure constants for calculating the new (0-1) line parameters. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Denver, Dept Phys, Denver, CO 80208 USA. Harvard Smithsonian Ctr Astrophys, Atom & Mol Phys Div, Cambridge, MA 02138 USA. Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. NASA, Langley Res Ctr, Div Atmospher Sci, Hampton, VA 23681 USA. RP Goldman, A (reprint author), Univ Denver, Dept Phys, Denver, CO 80208 USA. NR 27 TC 5 Z9 5 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD NOV PY 1998 VL 60 IS 5 BP 869 EP 874 DI 10.1016/S0022-4073(98)00089-2 PG 6 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 129YR UT WOS:000076492100013 ER PT J AU Langley, HD AF Langley, HD TI "The dammed red flags of the rebellion": The Confederate battle flag at Gettysburg SO JOURNAL OF SOUTHERN HISTORY LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Langley, HD (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SOUTHERN HISTORICAL ASSOC PI ATHENS PA UNIV GEORGIA, HISTORY DEPT, ATHENS, GA 30602 USA SN 0022-4642 J9 J SOUTHERN HIST JI J. South. Hist. PD NOV PY 1998 VL 64 IS 4 BP 750 EP 751 DI 10.2307/2587548 PG 2 WC History SC History GA 138QF UT WOS:000076983200035 ER PT J AU Wooninck, L Strassmann, JE Fleischer, RC Warner, RR AF Wooninck, L Strassmann, JE Fleischer, RC Warner, RR TI Characterization of microsatellite loci in a pelagic spawner: the bluehead wrasse, Thalassoma bifasciatum SO MOLECULAR ECOLOGY LA English DT Article DE bluehead wrasse; microsatellites; paternity; sperm competition ID MARKERS C1 Univ Calif Santa Barbara, Dept Ecol Evolut & Marine Biol, Santa Barbara, CA 93106 USA. Rice Univ, Dept Ecol & Evolut Biol, Houston, TX 77005 USA. Smithsonian Inst, Natl Zool Pk, Genet Mol Lab, Washington, DC 20008 USA. RP Wooninck, L (reprint author), Univ Calif Santa Barbara, Dept Ecol Evolut & Marine Biol, Santa Barbara, CA 93106 USA. RI Warner, Robert/M-5342-2013; OI Warner, Robert/0000-0002-3299-5685; Strassmann, Joan/0000-0003-0638-8440 NR 6 TC 7 Z9 7 U1 0 U2 2 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 NOV PY 1998 VL 7 IS 11 BP 1613 EP 1614 PG 2 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 137TT UT WOS:000076933000021 PM 9819911 ER PT J AU Fonseca, DM Atkinson, CT Fleischer, RC AF Fonseca, DM Atkinson, CT Fleischer, RC TI Microsatellite primers for Culex pipiens quinquefasciatus, the vector of avian malaria in Hawaii SO MOLECULAR ECOLOGY LA English DT Article DE avian malaria; Culex pipiens quinquefasciatus; Hawaii; Insecta; introduced species; microsatellites C1 Smithsonian Inst, Natl Zool Pk, Genet Mol Lab, Washington, DC 20008 USA. RP Fonseca, DM (reprint author), Smithsonian Inst, Natl Zool Pk, Genet Mol Lab, 3001 Connecticut Ave NW, Washington, DC 20008 USA. OI Fonseca, Dina/0000-0003-4726-7100 NR 4 TC 33 Z9 34 U1 0 U2 1 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 NOV PY 1998 VL 7 IS 11 BP 1617 EP 1619 PG 3 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 137TT UT WOS:000076933000024 PM 9819914 ER PT J AU Nicholson, KL Reichert, GA Mason, KO Puchnarewicz, EM Ho, LC Shields, JC Filippenko, AV AF Nicholson, KL Reichert, GA Mason, KO Puchnarewicz, EM Ho, LC Shields, JC Filippenko, AV TI Evidence for low-level AGN activity in the nucleus of the LINER galaxy NGC 4594 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE line : formation; galaxies : individual : NGC 4594; ultraviolet : galaxies; X-rays : galaxies ID ADVECTION-DOMINATED ACCRETION; DWARF SEYFERT NUCLEI; X-RAY-PROPERTIES; GALACTIC NUCLEI; STARBURST GALAXIES; COMPLETE SAMPLE; EMISSION; ULTRAVIOLET; QUASARS; SEARCH AB We investigate the properties of the low-ionization nuclear emission-line region (LINER) galaxy, NGC 4594, using data taken with the Faint Object Spectrograph on the Hubble Space Telescope (HST) and with the ASCA X-ray observatory. The ultraviolet spectrum shows only narrow-line emission (FWHM approximate to 800-1000 km s(-1)) with no evidence for broad emission-line components. The emission-line data are compared with shock and photoionization model predictions. Fast shock models are incompatible with the UV emission-line spectrum and the best fit is found with a model, devised by Shull & McKee, where slow shocks (100 km s(-1)) are incident on a relatively dense medium (n(0) = 100 cm(-3)). Among photoionization models the best agreement is obtained with a CLOUDY model which has an ionization parameter of U = 3.2 x 10(-4). The hard X-Pay ASCA data on NGC4594 yield a spectral index of alpha(X) = 0.62 +/- 0.03 which extrapolates, within the errors, to the soft X-ray spectrum measured with the ROSAT PSPC. When the ASCA and ROSAT data are combined, the best-fitting column density is N(H) = 5.3 x 10(20) cm(-2), slightly higher than the Galactic value in this direction. However, allowing for contamination by soft extended emission close to the nucleus, the column density to the nuclear source may be as high as 2.9 x 10(21) cm(-2). The multiwavelength spectrum of the NGC 4594 differs from those of luminous active galactic nuclei (AGN) in the relative weakness of the UV continuum. This is consistent with the Siemiginowska model for a low-state accretion disc. Advection-dominated disc models, which have been applied to low-luminosity AGN, also agree qualitatively with our data. C1 UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Ohio Univ, Dept Phys & Astron, Athens, OH 45701 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Nicholson, KL (reprint author), UCL, Mullard Space Sci Lab, Holmbury St Mary, Dorking RH5 6NT, Surrey, England. NR 51 TC 33 Z9 33 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD NOV 1 PY 1998 VL 300 IS 3 BP 893 EP 906 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 137AX UT WOS:000076892200021 ER PT J AU WEil, SE AF WEil, SE TI Courtly ghosts and aristocratic artifacts: The art museum as palace SO MUSEUM NEWS LA English DT Article C1 Smithsonian Inst, Washington, DC 20560 USA. RP WEil, SE (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 5 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 NOV-DEC PY 1998 VL 77 IS 6 BP 44 EP 49 PG 6 WC Art SC Art GA 133GW UT WOS:000076679700018 ER PT J AU Weldon, PJ Gaffney, ES AF Weldon, PJ Gaffney, ES TI An ancient integumentary gland in turtles SO NATURWISSENSCHAFTEN LA English DT Article C1 Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA 22630 USA. Amer Museum Nat Hist, Dept Vertebrate Paleontol, New York, NY 10024 USA. RP Weldon, PJ (reprint author), Smithsonian Inst, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. NR 14 TC 9 Z9 9 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0028-1042 J9 NATURWISSENSCHAFTEN JI Naturwissenschaften PD NOV PY 1998 VL 85 IS 11 BP 556 EP 557 DI 10.1007/s001140050550 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 141KX UT WOS:000077144100008 ER PT J AU Cote, R Segev, B Raizen, MG AF Cote, R Segev, B Raizen, MG TI Retardation effects on quantum reflection from an evanescent-wave atomic mirror SO PHYSICAL REVIEW A LA English DT Article ID DIELECTRIC SURFACE; DIFFRACTION; OPTICS; CAVITY; ENERGY; LIGHT; TIME AB We calculate the reflection probability for ultracold sodium atoms incident on an evanescent-wave atomic mirror. For low enough energies the reflection probability curves exhibit quantum effects that are sensitive to the long-range part of the potential and can therefore be used to resolve Casimir retardation effects. We also explore the accuracy of model potentials approximating the exact atom-wall effective potential. [S1050-2947(98)08811-8]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Univ Texas, Dept Phys, Austin, TX 78712 USA. RP Cote, R (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. NR 34 TC 21 Z9 21 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 NOV PY 1998 VL 58 IS 5 BP 3999 EP 4013 DI 10.1103/PhysRevA.58.3999 PG 15 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 138FT UT WOS:000076961300078 ER PT J AU Esry, BD AF Esry, BD TI Impact of spontaneous spatial symmetry breaking on the critical atom number for two-component Bose-Einstein condensates SO PHYSICAL REVIEW A LA English DT Article AB The consequences of spatial symmetry breaking in two-component Bose-Einstein condensates are explored for the Rb-85+Rb-87 system. It is shown that the mean-field critical number of Rb-85 atoms depends strongly on whether the single-particle wave function is symmetry preserving or symmetry breaking. This system thus provides a uniquely straightforward experimental means of observing spatial symmetry breaking. [S1050-2947(98)50911-0]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Esry, BD (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RI Esry, Brett/H-7511-2013 OI Esry, Brett/0000-0003-3207-8526 NR 14 TC 11 Z9 11 U1 0 U2 1 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 NOV PY 1998 VL 58 IS 5 BP R3399 EP R3402 DI 10.1103/PhysRevA.58.R3399 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 138FT UT WOS:000076961300008 ER PT J AU Medvedev, MV Diamond, PH AF Medvedev, MV Diamond, PH TI Self-organized states in cellular automata: Exact solution SO PHYSICAL REVIEW E LA English DT Article ID CRITICAL-BEHAVIOR; ABELIAN SANDPILE; TRANSPORT; MODELS; FLOW; AVALANCHES; DYNAMICS AB The spatial structure, fluctuations as well as all state probabilities of self-organized (steady) states of cellular automata can be found (almost) exactly and explicitly from their Markovian dynamics. The method is shown on an example of a natural sand pile model with a gradient threshold. [S1063-651X(98)06211-4]. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM mmedvedev@cfa.harvard.edu NR 21 TC 2 Z9 2 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD NOV PY 1998 VL 58 IS 5 BP 6824 EP 6827 DI 10.1103/PhysRevE.58.6824 PN B PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 139VV UT WOS:000077052300091 ER PT J AU Billeck, WT AF Billeck, WT TI Fluted point distribution in the Loess Hills of southwestern Iowa SO PLAINS ANTHROPOLOGIST LA English DT Article DE Paleoindian; Clovis; Folsom; Loess Hills; Iowa AB Clovis and Folsom points from Mills and Fremont counties in the Loess Hills of southwestern Iowa are mainly found on hilltops, the only part of the Paleoindian landscape that is likely to be exposed on the modern surface. Approximately half of the fluted points broke in manufacture. Most of the points are made of locally available chert. Nonlocal lithic material is also present, primarily in the form of finished points. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, Washington, DC 20560 USA. RP Billeck, WT (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, Washington, DC 20560 USA. NR 23 TC 2 Z9 2 U1 0 U2 0 PU PLAINS ANTHROPOLOGICAL SOC PI LINCOLN PA 410 WEDGEWOOD DRIVE, LINCOLN, NE 68510 USA SN 0032-0447 J9 PLAINS ANTHROPOL JI Plains Anthropol. PD NOV PY 1998 VL 43 IS 166 BP 401 EP 409 PG 9 WC Anthropology SC Anthropology GA 150XP UT WOS:000077691600005 ER PT J AU Dorr, LJ AF Dorr, LJ TI John J. Wurdack (1921-1998) 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 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 NOV PY 1998 VL 47 IS 4 BP 971 EP 973 PG 3 WC Plant Sciences; Evolutionary Biology SC Plant Sciences; Evolutionary Biology GA 145RV UT WOS:000077385900014 ER PT J AU Tseng, CH Wong, GP Pomeroy, VR Mair, RW Hinton, DP Hoffmann, D Stoner, RE Hersman, FW Cory, DG Walsworth, RL AF Tseng, CH Wong, GP Pomeroy, VR Mair, RW Hinton, DP Hoffmann, D Stoner, RE Hersman, FW Cory, DG Walsworth, RL TI Low-field MRI of laser polarized noble gas SO PHYSICAL REVIEW LETTERS LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; NMR IMAGING-SYSTEM; HYPERPOLARIZED HE-3; XE-129 GAS; XENON; ENHANCEMENT; DIFFUSION; HUMANS; IMAGES; LUNGS AB NMR images of laser polarized He-3 gas were obtained at 21 G using a simple, homebuilt instrument. At such low fields magnetic resonance imaging (MRI) of thermally polarized samples (e.g., water) is not practical. Low-field noble gas MRI has novel scientific, engineering, and medical applications. Examples include portable systems for diagnosis of lung disease, as well as imaging of voids in porous media and within metallic systems. [S0031-9007(98)07442-0]. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Brigham & Womens Hosp, Dept Radiol, Boston, MA 02115 USA. MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. Massachusetts Gen Hosp, NMR Ctr, Boston, MA 02129 USA. RP Tseng, CH (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Stoner, Richard/0000-0001-7949-6747 FU FDA HHS [BES-9612237] NR 40 TC 89 Z9 90 U1 2 U2 19 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 26 PY 1998 VL 81 IS 17 BP 3785 EP 3788 DI 10.1103/PhysRevLett.81.3785 PG 4 WC Physics, Multidisciplinary SC Physics GA 132DX UT WOS:000076616000059 PM 11543589 ER PT J AU Bloomer, JD Watson, DM Pipher, JL Forrest, WJ Ali, B Greenhouse, MA Satyapal, S Smith, HA Fischer, J AF Bloomer, JD Watson, DM Pipher, JL Forrest, WJ Ali, B Greenhouse, MA Satyapal, S Smith, HA Fischer, J TI A near-infrared study of NGC 7538 IRS 1, 2, and 3 SO ASTROPHYSICAL JOURNAL LA English DT Article DE H II regions; infrared : ISM : lines and bands; infrared : stars; ISM : individual (NGC 7538); open clusters and associations : individual (NGC 7538); stars : formation ID FE-II EMISSION; MOLECULAR CLOUDS; SUPERNOVA-REMNANTS; STAR-FORMATION; H-2 EMISSION; ORION NEBULA; WEAK LINES; REGIONS; INTERSTELLAR; NGC-7538 AB We present images of the cluster of embedded young stars designated NGC 7538 IRS 1, 2, and 3 in the J (1.25 mu m), H (1.64 mu m), and K (2.16 mu m) broad bands; the 1.64 mu m line of [Fe II]; the 2.12 mu m and 2.25 mu m lines of H-2; the 2.17 mu m Brackett gamma H-recombination line; and the 3.29 mu m "unidentifed" dust feature. The NGC 7538 IRS 2 compact H II region, as seen in Brackett gamma line emission, possesses a cometary morphology. We find evidence for a shell-like distribution of [Fe II] line emission along the periphery of the compact H II region. This morphology and the observed intensity ratio [Fe II] 1.64 mu m)I(Br gamma) imply that the [Fe II] line emission emanates from shocked stellar wind material. We observe arcs of H, line emission immediately exterior to the [Fe II] line emission shell and suggest that these arcs delineate molecular cloud material shocked via collision with the stellar wind. We observe larger area with centers of curvature displaced from each other and IRS 2, in broad-band-continuum, H-2-line, and 3.29 mu m feature emission, and suggest that these arcs represent molecular gas (either shocked or UV-excited) and dust swept up during distinct episodes of stellar mass ejection. We submit that the morphological and energetic evidence favors a "stellar wind bow shock" interpretation, in which the motion of the central O star with respect to the surrounding molecular cloud, in conjunction with the star's high-velocity stellar wind and episodic mass ejection, gives rise to the observed general cometary morphology and circum-H II region emission. C1 Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. RP Bloomer, JD (reprint author), Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. NR 57 TC 20 Z9 20 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 20 PY 1998 VL 506 IS 2 BP 727 EP 742 DI 10.1086/306268 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LM UT WOS:000077779100022 ER PT J AU Becker, CM Remillard, RA Rappaport, SA McClintock, JE AF Becker, CM Remillard, RA Rappaport, SA McClintock, JE TI Bipolar jets and orbital dynamics of the supersoft X-ray source RX J0019.8+2156 SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; novae, cataclysmic variables; stars : individual (RX J0019.8+2156); white dwarfs; X-rays : stars ID LARGE-MAGELLANIC-CLOUD; WHITE-DWARF MODELS; ALL-SKY SURVEY; OPTICAL VARIABILITY; CAL-87; J0513.9-6951; BINARY AB Between 1994 July and 1997 February we monitored the optical spectrum of RX J0019.8 +2156. This supersoft X-ray source is one of only two accreting white dwarfs in the Galaxy that are thought to be burning hydrogen on their surface as a consequence of a high rate of mass transfer from a binary companion. Accurate orbital ephemerides are derived from radial velocity measurements for the white dwarf, which are obtained from strong He II emission lines with a stable velocity semiamplitude of K = 71.2 +/- 3.6 km s(-1). We report the discovery of transient, low-velocity, bipolar jets. These jets are represented by redshifted-blueshifted pairs of emission lines from H and He II with an outflow velocity of v cos (i) similar to 815 km s(-1), where i is the binary inclination angle. When present, the jet lines seen in H alpha also exhibit an orbital modulation of 71 km s(-1) which strengthens the interpretation that this is the orbital velocity of the white dwarf and also indicates that the jets are oriented nearly perpendicular to the orbital plane. On most occasions, the H emission line profiles are further altered by P Cygni absorption effects, and the strength of this absorption is also dependent on binary phase. We show that the jets and the P Cygni features have very different temporal characteristics and binary phase dependence; thus, we conclude that the outflowing material and the absorbing wind must have essentially different geometries. Finally, the measured mass function is combined with binary evolution models to suggest a limit on the inclination angle, i < 40 degrees. A particular model invoked to explain a high rate of mass transfer requires 16 degrees < i < 25 degrees. However, at such small inclination it is difficult to explain the large amplitude of the orbital light curve (similar to 0.5 mag). Alternatively, the results could signify substantial vertical structure in the accretions disks of supersoft X-ray sources. By contrast, a simple model fit to the jet outflow lines indicates an orbital inclination angle of 35 degrees < i < 60 degrees. C1 MIT, Ctr Space Res, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Becker, CM (reprint author), MIT, Ctr Space Res, Cambridge, MA 02139 USA. NR 31 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 OCT 20 PY 1998 VL 506 IS 2 BP 880 EP 891 DI 10.1086/306272 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LM UT WOS:000077779100035 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI N.C. Wyeth. 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 OCT 15 PY 1998 VL 123 IS 17 BP 64 EP 64 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 128JX UT WOS:000076403600037 ER PT J AU Feinstein, N Cairns, SD AF Feinstein, N Cairns, SD TI Learning from the collector: A survey of azooxanthellate corals affixed by Xenophora (Gastropoda : Xenophoridae), with an analysis and discussion of attachment patterns SO NAUTILUS LA English DT Article DE Carrier shells; Mollusca; gastropods; ahermatypic corals AB All species of the gastropod family Xenophoridae affix foreign objects to the upper shell surface. Affixed objects may include bivalve shells, smaller gastropod shells, shell fragments, and coral skeletons, as well as a wide array of inorganic material. In deep water, Xenophora may serve as useful proxy collectors of benthic organisms. Since 1842, coral skeletons have been noted among the attached objects, but this association has never been studied in detail. This paper surveys 227 Xenophora shells, comprising 8 species from 69 stations, for affixed azooxanthellate corals. Five hundred and eighty-one coralla were found, representing 74 coral species, 2 of which remain undescribed. Twenty-four of the affixed coralla were alive at the time the Xenophora hosts were collected; Xenophora not only collect live corals, but corals can remain alive long after being affixed. Corals were found at 6 sites where they had previously been unknown, and the geographic ranges of 29 species of coral were expanded as a result of specimens found on Xenophora. This paper has two sections. In the first, quantitative observations were made on the orientation of affixed corals; statistical analysis of these observations revealed non-random patterns of attachment, based on orientation of both the long ads of the coral and the coral calice. Qualitative observations suggest that species of Xenophora favor corals of particular shapes. In the second section, the speculations of previous authors regarding the ecological basis for attachment behavior are summarized and new theories are discussed. Four of these explanations suggest defensive adaptations, and the remaining 3 are functional support adaptations. Three of these hypotheses (armor, tactile camouflage, and snow-shoeing) are proposed for the first time in this paper. C1 Harvard Univ, Cambridge, MA 02138 USA. RP Cairns, SD (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 18 TC 3 Z9 3 U1 3 U2 10 PU BAILEY-MATTHEWS SHELL MUSEUM PI SANIBEL PA C/O DR JOSE H LEAL, ASSOCIATE/MANAGING EDITOR, 3075 SANIBEL-CAPTIVA RD, SANIBEL, FL 33957 USA SN 0028-1344 J9 NAUTILUS JI Nautilus PD OCT 15 PY 1998 VL 112 IS 3 BP 73 EP 83 PG 11 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 131YK UT WOS:000076602700001 ER PT J AU Beck, AL Labandeira, CC AF Beck, AL Labandeira, CC TI Early Permian insect folivory on a gigantopterid-dominated riparian flora from north-central Texas SO PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY LA English DT Review DE diet; trophic analysis; herbivorous taxa; Insecta; Plantae; Permian; paleoecology ID ECOLOGICAL COMMUNITIES; TAXONOMIC DIVERSITY; POLLINATION BIOLOGY; FOSSIL RECORD; HERBIVORY; DEFENSE; HISTORY; GROWTH; PLANTS; FOREST AB Quantitative analysis of 11,562 cm(2) of foliar surface area from an Early Permian flora from north-central Texas reveals that 2.6% was removed by insect folivores. Of the 1346 foliar items analyzed, 31.8% were attacked by insect folivores. This Permian insect herbivory approximated one-third the level in modern tropical to temperate forests. Three taxa of Gigantopteridaceae exhibited disproportionately high insect consumption levels, ranging from 3.1 to 4.4% of leaf area, and attack frequencies of 39.6 to 82.8% - levels comparable to taxon-specific values for modem woody dicotyledonous angiosperms. Qualitative analysis of folivory type also indicates that five of the eight categories of herbivore damage occurring on this flora were confined to or overwhelmingly represented on Gigantopteridaceae, suggesting preferential host specificity for Gigantopteridaceae by insect folivores. By contrast, other pteridophylls, conifers, cycadophytes, and two taxa of uncertain affinity, showed low levels of leaf area removal and attack frequencies. The Gigantopteridaceae, an enigmatic group of Permian plants with large, megaphyllous foliage, foreshadowed physiognomic attributes occurring in later angiosperms. Both groups had similar consumption patterns and intensities by insect folivores. Ln this moderately diverse Early Permian flora, insect folivory was significant, at least in one riparian environment outside the Euramerican coal-swamp ecosystem, indicating that modern modes and magnitudes of insect consumption of vascular plant tissue were in place during the Late Paleozoic. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. Univ Maryland, Dept Entomol, College Pk, MD 20742 USA. RP Labandeira, CC (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. EM labandec@nmnh.si.edu NR 171 TC 51 Z9 53 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-0182 J9 PALAEOGEOGR PALAEOCL JI Paleogeogr. Paleoclimatol. Paleoecol. PD OCT 15 PY 1998 VL 142 IS 3-4 BP 139 EP 173 DI 10.1016/S0031-0182(98)00060-1 PG 35 WC Geography, Physical; Geosciences, Multidisciplinary; Paleontology SC Physical Geography; Geology; Paleontology GA 108DK UT WOS:000075250600004 ER PT J AU McLaughlin, BM Bell, KL AF McLaughlin, BM Bell, KL TI Electron-impact excitation of the fine-structure levels (1s(2)2s(2)2p(3) S-4(3/2)0, D-2(5/2,3/2)0, P-2(3/2,1/2)0) of singly ionized atomic oxygen SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID EFFECTIVE COLLISION STRENGTHS; O-II; INTERMULTIPLET 1S(2)2S(2)2P(3); FORBIDDEN TRANSITIONS; OPACITY CALCULATIONS; SPECTRUM; 1S(2)2S2P(4); 2S(2)2P(3); PROGRAM; STATES AB Effective collision strengths for OII ions are evaluated from electron-impact excitation collision strengths of singly ionized atomic oxygen (OII) calculated in the close-coupling approximation using the ab initio R-matrix method at the Breit-Pauli approximation level. The lowest 21 fine-structure levels arising from the 11 2s(2)2p(3), 2s2p(4), 2s(2)2P(2)3s IS target states are included in the calculation. The effective collision strengths for all forbidden transitions between the ground configuration levels 1s(2)2s(2)2p(3) S-4(3/2)o, D-2(5/2,3/2)o, P-2(3/2,1/2)o are obtained by averaging the electron collision strengths, for a wide range of incident electron energies, over a Maxwellian distribution of velocities. Results are presented for electron temperatures in the range 2000-1000000 K, applicable to many laboratory and astrophysical plasmas. We believe that the results are the most accurate to date and so should be used in preference to previous values available in the literature. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Queens Univ Belfast, Dept Appl Math & Theoret Phys, Belfast BT7 1NN, Antrim, North Ireland. RP McLaughlin, BM (reprint author), Queens Univ Belfast, Dept Appl Math & Theoret Phys, Belfast BT7 1NN, Antrim, North Ireland. NR 39 TC 44 Z9 44 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD OCT 14 PY 1998 VL 31 IS 19 BP 4317 EP 4329 DI 10.1088/0953-4075/31/19/017 PG 13 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 131VX UT WOS:000076596900017 ER PT J AU Hersch, JS Heller, EJ AF Hersch, JS Heller, EJ TI Observation of proximity resonances in a parallel-plate waveguide SO PHYSICAL REVIEW LETTERS LA English DT Article ID BILLIARDS AB Experiments with dielectric scatterers in a parallel-plate waveguide have verified for the first time the existence of proximity resonances in two dimensions. A numerical solution to the scattering problem supports the analysis of the experimental data. [S0031-9007(98)07360-8]. C1 Harvard Univ, Dept Phys, Cambridge, MA 02138 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hersch, JS (reprint author), Harvard Univ, Dept Phys, Cambridge, MA 02138 USA. EM hersch@monsoon.harvard.edu; heller@physics.harvard.edu NR 17 TC 12 Z9 12 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 12 PY 1998 VL 81 IS 15 BP 3059 EP 3062 DI 10.1103/PhysRevLett.81.3059 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400003 ER PT J AU Seljak, U AF Seljak, U TI Weak lensing reconstruction and power spectrum estimation: Minimum variance methods SO ASTROPHYSICAL JOURNAL LA English DT Article DE gravitational lensing; large-scale structure of universe; methods : numerical ID LARGE-SCALE STRUCTURE; GALAXIES; INVERSION; MAPS AB Large-scale structure distorts the images of background galaxies, which allows one to measure directly the projected distribution of dark matter in the universe and determine its power spectrum. Here we address the question of how to extract this information from the observations. We derive minimum variance estimators for the projected density reconstruction and its power spectrum and apply them to simulated data sets, showing that they give a good agreement with the theoretical minimum variance expectations. The same estimator can also be applied to the cluster reconstruction, where it remains a useful reconstruction technique, although it is no longer optimal for every application. The method can be generalized to include nonlinear cluster reconstruction and photometric information on redshifts of background galaxies in the analysis. We also address the question of how to obtain directly the three-dimensional power spectrum from the weak lensing data. We derive a minimum variance quadratic estimator, which maximizes the likelihood function for the three-dimensional power spectrum and can be computed either from the measurements directly or from the two-dimensional power spectrum. The estimator correctly propagates the errors and provides a full correlation matrix of the estimates. It can be generalized to the case where redshift distribution depends on the galaxy photometric properties, which allows one to measure both the three-dimensional power spectrum and its time evolution. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 43 TC 64 Z9 64 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 OCT 10 PY 1998 VL 506 IS 1 BP 64 EP 79 DI 10.1086/306225 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LJ UT WOS:000077778800006 ER PT J AU Alves, J Lada, CJ Lada, EA Kenyon, SJ Phelps, R AF Alves, J Lada, CJ Lada, EA Kenyon, SJ Phelps, R TI Dust extinction and molecular cloud structure: L977 SO ASTROPHYSICAL JOURNAL LA English DT Article DE dust, extinction; ISM : individual (L977, L981); ISM : structure; techniques : photometric ID INTERSTELLAR EXTINCTION; INTRINSIC COLORS; PHOTOMETRY; STARS; MICRON AB We report results of a near-infrared imaging survey of L977, a dark cloud in Cygnus seen in projection against the plane of the Milky Way. We use measurements of the near-infrared color excess and positions of the 1628 brightest stars in our survey to measure directly dust extinction through the cloud following the method described by Lada and coworkers. We spatially convolve the individual extinction measurements with a square filter 90 " in size to construct a large-scale map of extinction in the cloud. We integrate over this map to derive a total mass of M-L977 = (660 +/- 30)(D/500 pc)(2) M. and, via a comparison of source counts with predictions of a Galactic model, estimate a distance to L977 of 500 +/- 100 pc. We find a correlation between the measured dispersion in our extinction determinations and the extinction, which is very similar to that found for the dark cloud IC 5146 in a previous study. We interpret this as evidence for the presence of structure on scales smaller than the 90 " resolution of our extinction map. To further investigate the structure of the cloud we construct the frequency distribution of the 1628 individual extinction measurements in the L977 cloud. The shape of the distribution is similar to that of the IC 5146 cloud. Monte Carlo modeling of this distribution suggests that in the range 2 mag < A(V) < 40 mag (or roughly 1 pc < r < 0.1 pc) the material inside L977 is characterized by a density profile rho(r) proportional to r(-2). Direct measurement of the radial profile of a portion of the cloud confirms this result. At the lower Galactic latitude of L977, we find both the mean and dispersion of the infrared colors of field stars to be larger than those observed toward IC 5146. This produces an increase of about a factor of 2 in the minimum or threshold value of extinction that can be reliably measured toward L977 with this technique. Nevertheless, the accuracy in an extinction map pixel is not significantly different toward L977 because of the increased number of field stars at this latitude. We also find an increase in the number of detected giant stars at the lower Galactic latitude of the survey by almost a factor of 2. Most of these excess stars suffer extraneous extinction and are probably red giants seen along the disk of the Milky Way up to distances of similar to 15 kpc and reddened by unrelated background molecular clouds along this direction of the Galaxy. We discuss a possible application of this observable to Galactic structure studies on the plane of the Galaxy. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florida, Dept Astron, Gainesville, FL 32608 USA. Observ Carnegie Inst Washington, Pasadena, CA 91101 USA. Univ Lisbon, Dept Phys, P-1699 Lisbon, Portugal. RP Alves, J (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Kenyon, Scott/0000-0003-0214-609X NR 36 TC 106 Z9 107 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 10 PY 1998 VL 506 IS 1 BP 292 EP 305 DI 10.1086/306243 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LJ UT WOS:000077778800022 ER PT J AU Navascues, DBY Stauffer, JR Randich, S AF Navascues, DBY Stauffer, JR Randich, S TI Stellar activity in coeval open clusters: Praesepe and the Hyades SO ASTROPHYSICAL JOURNAL LA English DT Article DE open clusters and associations : individual (Hyades, Praesepe); stars : activity; stars : chromospheres; stars : late-type; X-rays : stars ID LOW-MASS STARS; X-RAY SURVEY; ROTATIONAL VELOCITIES; PLEIADES; ROSAT; PHOTOMETRY; BINARIES; MEMBERS; SEARCH AB Randich & Schmitt found that the coronal activity of solar-type and low-mass stars in Praesepe is significantly lower than that of stars in the Hyades cluster. This result is quite surprising, since the Hyades and Praesepe have approximately the same age and metallicity and are often thought to have originated in the same giant molecular cloud complex. We have carried out several tests in order to find a possible explanation for this result. We have measured radial velocities of two groups of Praesepe stars (a dF-dK sample and a dM sample) and have measured H alpha as a chromospheric activity index for the dM sample. Based on analyses of these data, we conclude that the Praesepe catalog used in the X-ray analysis does not contain a significant number of nonmembers and, thus, that membership problems do not seem to be the cause of the Randich & Schmitt result. The comparison of the H alpha equivalent widths for the M dwarfs in Praesepe with those in the Hyades indicates that, at least for stars in this mass range, the Praesepe stars are as active or more active than their Hyades counterparts. The similarity of chromospheric emission allows us to reject differences in the rotational velocity distribution as the origin of the dissimilar L-x luminosity functions. We have also analyzed a few ROSAT PSPC pointings of Praesepe in order to obtain a new and independent estimate of the X-ray luminosities and upper limits for a small sample of Praesepe members. This analysis suggests that the previous ROSAT PSPC analysis produced slightly optimistic X-ray upper limits; however, the differences between the old and new upper limits are not large enough to explain the dichotomy in the X-ray properties of Praesepe and the Hyades. Therefore, our examination of the available data does not provide a clear reason to explain why the X-ray luminosity functions of the two clusters are different. Part of the explanation could be found in the binaries. Speculatively, these clusters could have different orbital period distributions, with more short-period binaries among the Hyades, which would show larger coronal activity. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Osservatorio Astrofis Arcetri, I-50125 Florence, Italy. RP Navascues, DBY (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM dbarrado@cfa.harvard.edu; jstauffer@cfa.harvard.edu; randich@arcetri.astro.it RI Barrado Navascues, David/C-1439-2017; OI Barrado Navascues, David/0000-0002-5971-9242; Randich, Sofia/0000-0003-2438-0899 NR 41 TC 26 Z9 26 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 10 PY 1998 VL 506 IS 1 BP 347 EP 359 DI 10.1086/306241 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LJ UT WOS:000077778800028 ER PT J AU Li, J Raymond, JC Acton, LW Kohl, JL Romoli, M Noci, G Naletto, G AF Li, J Raymond, JC Acton, LW Kohl, JL Romoli, M Noci, G Naletto, G TI Physical structure of a coronal streamer in the closed-field region as observed from UVCS/SOHO and SXT/YOHKOH SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona; Sun : fundamental parameters; Sun : magnetic fields; Sun : X-rays, gamma rays ID X-RAY TELESCOPE; MAGNETIC-FIELD; SOLAR CORONA; WIND AB We analyze a coronal helmet streamer observed on 1996 July 25 using instruments aboard two solar spacecraft, the Ultraviolet Coronagraph Spectrometer (UVCS) on board Solar and Heliospheric Observatory (SOHO) and the Soft X-Ray Telescope (SXT) on board Yohkoh. We derive temperatures and electron densities at 1.15 R. from SXT/Yohkoh observations. At this height, the streamer temperature is about log T (K) = 6.28 +/- 0.05, and the electron density is about log n(e)(cm(-3)) = 8.09 +/- 0.26, while at 1.5 R. a temperature of log T (K) = 6.2 and a density of log n(e)(cm(-3)) = 7.1 are obtained by UVCS/SOHO. Within the measurement uncertainty this suggests a constant temperature from the base of the streamer to 1.5 R.. Electron density measurements suggest that the gas in the streamer core is close to hydrostatic equilibrium. Comparison with potential field models for the magnetic field suggests a plasma beta larger than 1 in the closed-field region in the streamer. In deriving electron densities and temperatures from the SXT/Yohkoh data, we include the effects of abundance anomalies on the SXT filter response. We use the elemental abundances derived from the UVCS/SOHO observations to estimate the first ionization potential and gravitational settling effects. We then give the set of abundances for the solar corona, which agrees with our observations. In addition, we analyzed the SXT data from 6 consecutive days. We found that from 1996 July 22 to July 27, the physical properties of the streamer are nearly constant. We conclude that we may be observing the same loop system over 6 days. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. Univ Florence, I-50125 Florence, Italy. Univ Padua, I-35131 Padua, Italy. RP Li, J (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Romoli, Marco/H-6859-2012; Naletto, Giampiero/S-6329-2016 OI Naletto, Giampiero/0000-0003-2007-3138 NR 31 TC 63 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 OCT 10 PY 1998 VL 506 IS 1 BP 431 EP 438 DI 10.1086/306244 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LJ UT WOS:000077778800034 ER PT J AU Neufeld, DA Melnick, GJ Harwit, M AF Neufeld, DA Melnick, GJ Harwit, M TI Infrared Space Observatory observations of molecular hydrogen in HH 54: Measurement of a nonequilibrium ratio of ortho- to para-H-2 SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : ISM : lines and bands; ISM : molecules; molecular processes ID HERBIG-HARO OBJECTS; FLUORESCENT H-2; EMISSION; CLOUDS; HUBBLE-12; NGC-2023; NEBULA AB We have detected the S(1), S(2), S(3), S(4), and S(5) pure rotational lines of molecular hydrogen toward the outflow source HH 54 using the Short Wavelength Spectrometer on board the Infrared Space Observatory. The observed H-2 line ratios indicate the presence of warm molecular gas with an H-2 density of at least 10(5) cm(-3) and a temperature similar to 650 K in which the ratio of ortho- to para-H, is only 1.2 +/- 0.4, significantly smaller than the equilibrium ratio of 3 expected in gas at that temperature. These observations imply that the measured ratio of ortho- to para-H-2 is the legacy of an earlier stage in the thermal history of the gas when the gas had reached equilibrium at a temperature less than or similar to 90 K. Based upon the expected timescale for equilibration, we argue that the nonequilibrium ratio of ortho- to para-H-2 observed in HH 54 serves as a chronometer that places a conservative upper limit of similar to 5000 yr on the period for which the emitting gas has been warm. The S(2)/S(1) and S(3)/S(1) H-2 line ratios measured toward HH 54 are consistent with recent theoretical models of Timmermann for the conversion of para- to ortho-H-2 behind slow, C-type shocks, but only if the preshock ratio of ortho- to para-H-2 was less than or similar to 0.2. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Cornell Univ, Ithaca, NY 14853 USA. RP Neufeld, DA (reprint author), Johns Hopkins Univ, Dept Phys & Astron, 3400 N Charles St, Baltimore, MD 21218 USA. NR 32 TC 58 Z9 58 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 10 PY 1998 VL 506 IS 1 BP L75 EP L78 DI 10.1086/311636 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LL UT WOS:000077779000018 ER PT J AU Wood, K Whitney, B AF Wood, K Whitney, B TI Scattered light signatures of magnetic accretion in classical T Tauri stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; stars : pre-main-sequence; stars : rotation; stars : spots ID MAGNETOCENTRIFUGALLY DRIVEN FLOWS; ORION-NEBULA-CLUSTER; YOUNG STARS; ROTATION PERIODS; DISK ACCRETION; NEUTRON STARS; VARIABILITY; FUNNEL; MODEL; ZONE AB The magnetic accretion model as applied to T Tauri stars predicts the formation of hot spots or rings on the stellar surface where accreting disk material impacts the stellar surface at or near the magnetic poles. When the magnetic poles are not aligned with the stellar rotation axis, or the hot spots are nonuniform, brightness variations arise as the hot spots rotate into and out of view. We have investigated the effects on the scattered light images of a T Tauri star-plus-disk system of nonaxisymmetric illumination of the circumstellar disk by hot starspots. We find that changes in the scattered light pattern occur during a stellar rotation period. These changes are observable with current high-resolution imagery and provide a further observational test of the magnetic accretion theory. The observed brightening and dimming of HH 30's scattered light disk may be explained by such a model, although further synoptic observations are required to confirm this. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Prism Computat Sci Inc, Madison, WI 53703 USA. RP Wood, K (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 30 TC 25 Z9 25 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 10 PY 1998 VL 506 IS 1 BP L43 EP L45 DI 10.1086/311643 PN 2 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LL UT WOS:000077779000011 ER PT J AU Alroy, J AF Alroy, J TI Cope's rule - Response SO SCIENCE LA English DT Letter C1 Smithsonian Inst, Dept Paleobiol, Washington, DC 20560 USA. RP Alroy, J (reprint author), Smithsonian Inst, Dept Paleobiol, Washington, DC 20560 USA. RI Alroy, John/B-4585-2009 NR 2 TC 0 Z9 0 U1 0 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 OCT 2 PY 1998 VL 282 IS 5386 BP 51 EP 51 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 126LM UT WOS:000076294900026 ER PT J AU Kelloff, CL McKee, GS AF Kelloff, CL McKee, GS TI A new species of Hecistopteris from Guyana, South America SO AMERICAN FERN JOURNAL LA English DT Article C1 Smithsonian Inst, Dept Bot MRC 166, Washington, DC 20560 USA. RP Kelloff, CL (reprint author), Smithsonian Inst, Dept Bot MRC 166, Washington, DC 20560 USA. NR 2 TC 2 Z9 3 U1 0 U2 0 PU AMER FERN SOC INC PI WASHINGTON PA C/O DAVID B LELLINGER, SMITHSONIAN INST, BOTANY DEPT, WASHINGTON, DC 20560 USA SN 0002-8444 J9 AM FERN J JI Am. Fern J. PD OCT-DEC PY 1998 VL 88 IS 4 BP 155 EP 157 DI 10.2307/1547767 PG 3 WC Plant Sciences SC Plant Sciences GA 159VJ UT WOS:000078195500003 ER PT J AU Tommasini, P Timmermans, E Piza, AFRD AF Tommasini, P Timmermans, E Piza, AFRD TI The hydrogen atom as an entangled electron-proton system SO AMERICAN JOURNAL OF PHYSICS LA English DT Article ID DECOHERENCE; STATES AB We illustrate the description of correlated subsystems by studying the simple two-body hydrogen atom. We study the entanglement of the electron and proton coordinates in the exact analytical solution. This entanglement, which we quantify in the framework of the density matrix formalism, describes correlations in the electron-proton motion. (C) 1998 American Association of Physics Teachers. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo, Brazil. RP Tommasini, P (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. NR 16 TC 18 Z9 18 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD OCT PY 1998 VL 66 IS 10 BP 881 EP 886 DI 10.1119/1.18977 PG 6 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 125JM UT WOS:000076234500010 ER PT J AU Nam, VS Yen, NT Kay, BH Marten, GG Reid, JW AF Nam, VS Yen, NT Kay, BH Marten, GG Reid, JW TI Eradication of Aedes aegypti from a village in Vietnam, using copepods and community participation SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID MESOCYCLOPS-ASPERICORNIS COPEPODA; BIOLOGICAL-CONTROL; CYCLOPOID COPEPODS; FRENCH-POLYNESIA; CULICIDAE; DIPTERA; CYCLOPIDAE; ALBOPICTUS; CONTAINERS; CRUSTACEA AB In northern Vietnam, copepods of the genus Mesocyclops were used for biological control of Aedes aegypti, the principal vector of dengue viruses, by inoculation into wells, large cement tanks, ceramic jars, and other domestic containers that served as Ae. aegypti breeding sites. The use of Mesocyclops was complemented by community participation with respect to recycling to eliminate unused and discarded containers that collected rainwater and provided Ae. aegypti breeding sites that could not be treated effectively with Mesocyclops. Aedes aegypti disappeared from 400 houses of the treated village in August 1994 and has not reappeared, a result of particular significance, because there are virtually no other recorded instances of eradicating this mosquito anywhere in the world during the past 25 years, and certainly not with community-based approaches. When used in combination with community recycling, Mesocyclops is an easy and inexpensive method of Ae. aegypti control that should be effective for many communities in Vietnam and elsewhere. C1 Queensland Inst Med Res, Mosquito Control Lab, PO Royal Brisbane Hosp, Brisbane, Qld 4029, Australia. Natl Inst Hyg & Epidemiol, Hanoi, Vietnam. Kwansei Gakuin Univ, Hyogo, Japan. Smithsonian Inst, Washington, DC 20560 USA. RP Kay, BH (reprint author), Queensland Inst Med Res, Mosquito Control Lab, PO Royal Brisbane Hosp, Brisbane, Qld 4029, Australia. NR 21 TC 59 Z9 61 U1 1 U2 4 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 USA SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD OCT PY 1998 VL 59 IS 4 BP 657 EP 660 PG 4 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA 129QD UT WOS:000076473700034 ER PT J AU Condit, R Sukumar, R Hubbell, SP Foster, RB AF Condit, R Sukumar, R Hubbell, SP Foster, RB TI Predicting population trends from size distributions: A direct test in a tropical tree community SO AMERICAN NATURALIST LA English DT Article DE tropical forest; population change; size distribution ID NEOTROPICAL FOREST; ENGELMANN SPRUCE; LODGEPOLE PINE; DYNAMICS; MODEL; CONSERVATION; MONODOMINANT; NOTHOFAGUS; VEGETATION; MANAGEMENT AB Forest ecologists often evaluate how well the species composition of saplings in the understory matches that of the canopy: absence of juveniles suggests that a tree species is suffering population decline. Here we offer a theoretical and empirical test of this assertion using data from a 50-ha census plot in panama. Theory indicates that higher rates of population change, lambda, lead to more steeply declining size distributions (more juveniles relative to adults). But other parameters also affect the size distribution: lower growth rate of juveniles and lower survival at any size produce more steeply declining size distributions as well. Empirical evaluation of 216 tree populations showed that juvenile growth was the strongest predictor of size distribution, in the direction predicted by theory. Size distribution did correlate with population growth, but weakly and only in understory species, not canopy species. Size distribution did not correlate with the growth rate of larger individuals nor with survival. Results suggest that static information on the size distribution is not a good predictor of future population trends, while demographic information is. Fast-growing species will have fewer juveniles in the understory than slow-growing species, even when population growth is equal. C1 Smithsonian Trop Res Inst, Ctr Trop Forest Sci, Unit 0948, APO, AA 34002 USA. Indian Inst Sci, Ctr Ecol Sci, Bangalore 560012, Karnataka, India. Princeton Univ, Dept Ecol Evolut & Behav, Princeton, NJ 08544 USA. Field Museum Nat Hist, Dept Bot, Chicago, IL 60605 USA. RP Condit, R (reprint author), Smithsonian Trop Res Inst, Ctr Trop Forest Sci, Unit 0948, APO, AA 34002 USA. EM rick@ctfs.stri.si.edu; rsuku@ces.iisc.ernet.in; shubbell@phoenix.princeton.edu; foster@fmnh785.fmnh.org RI Raman, Sukumar/C-9809-2013 NR 39 TC 166 Z9 185 U1 2 U2 38 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0003-0147 J9 AM NAT JI Am. Nat. PD OCT PY 1998 VL 152 IS 4 BP 495 EP 509 DI 10.1086/286186 PG 15 WC Ecology; Evolutionary Biology SC Environmental Sciences & Ecology; Evolutionary Biology GA 121LH UT WOS:000076014900001 PM 18811360 ER PT J AU Thompson, KV AF Thompson, KV TI Spatial integration in infant sable antelope, Hippotragus niger SO ANIMAL BEHAVIOUR LA English DT Article ID TAILED DEER FAWNS; REPRODUCTIVE SYNCHRONY; BIRTH SYNCHRONY; MATERNAL-CARE; SOCIAL PLAY; HOUSE MICE; CALVES; STRATEGIES; DOMINANCE; BEHAVIOR AB I studied the relationship between the timing of birth relative to other births in the social group, and the rate of spatial integration into the herd in six cohorts of semi-free-ranging infant sable antelope at the National Zoological Park's Conservation and Research Center near Front Royal, Virginia. All calves spent the initial few days of life resting in seclusion ('hiding'), and interacted with mothers and other conspecifics only during activity bouts. With time, calves became increasingly likely to rest apart from the herd with other calves in creches, and by 6 weeks of age, calves remained with the herd throughout all resting and activity bouts. The rate of spatial integration for individual calves depended upon the calf's birth date and the availability of peers of similar age (birth clustering). Only the first few calves born in each cohort were observed in creches, and creche groups synchronized their entry into the herd. First-born calves remained in creches longer and began resting with the herd later in life than calves born later in the cohort. Last-born calves typically did not form creches, but instead rested with the herd from an early age. Other infants may;serve as social cover during the time that infants form creches and when they first begin to accompany the herd. The observed individual differences ii; the rate of spatial integration may represent individual adjustments in response to the varying degrees of protection offered by the spatial environment. (C) 1998 The Association for the Study of Animal Behaviour. C1 Univ Maryland, Coll Life Sci, Dept Zool, Biol Sci Program, College Pk, MD 20742 USA. Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. RP Thompson, KV (reprint author), Univ Maryland, Coll Life Sci, Dept Zool, Biol Sci Program, 1209 Symons Hall, College Pk, MD 20742 USA. RI Thompson, Katerina/B-6146-2009 NR 49 TC 5 Z9 5 U1 5 U2 10 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 OCT PY 1998 VL 56 BP 1005 EP 1014 DI 10.1006/anbe.1998.0866 PN 4 PG 10 WC Behavioral Sciences; Zoology SC Behavioral Sciences; Zoology GA 134RE UT WOS:000076755700023 ER PT J AU Brown, JL Wildt, DE AF Brown, JL Wildt, DE TI Reproductive research in wildlife species - Preface SO ANIMAL REPRODUCTION SCIENCE LA English DT Editorial Material C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Brown, JL (reprint author), Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. NR 0 TC 1 Z9 1 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 OCT PY 1998 VL 53 IS 1-4 BP 1 EP 2 PG 2 WC Agriculture, Dairy & Animal Science; Reproductive Biology SC Agriculture; Reproductive Biology GA 137KH UT WOS:000076913600001 ER PT J AU Morrow, CJ Monfort, SL AF Morrow, CJ Monfort, SL TI Ovarian activity in the scimitar-horned oryx (Oryx dammah) determined by faecal steroid analysis SO ANIMAL REPRODUCTION SCIENCE LA English DT Article DE faecal steroids; noninvasive monitoring; ultrasonography; progesterone; oestrogens; LH; scimitar-horned oryx ID ADDAX ADDAX-NASOMACULATUS; ESTROUS-CYCLE; ARTIFICIAL-INSEMINATION; REPRODUCTIVE-BIOLOGY; PREGNANCY DIAGNOSIS; METABOLITES; FECES; PROGESTERONE; ESTROGENS; EXCRETION AB Ultrasonography and radioimmunoassay (RIA) of serum oestradiol-17 beta, luteinizing hormone (LH) and progesterone, and faecal oestrogen and progestin was used to assess ovarian activity in the scimitar-horned oryx (Oryx dammah). Ovarian examination using ultrasonography revealed maximal follicle and corpus luteum (CL) diameters of 15 and 32 mm, respectively. Steroid hormone metabolite distribution among individual faecal pellets within the same defaecation was relatively homogeneous with coefficients of variation averaging 10.2 +/- 1.8% and 16.2 +/- 4.6% for oestrogens and progestins, respectively. Elevated faecal oestrogen concentrations were associated with large (> 10 mm) antral follicles detected by ultrasonography. Periovulatory peaks in faecal oestrogen excretion, coincident with nadirs in progestin excretion, were detected in three females. Faecal progestin excretion exhibited a similar temporal pattern to serum progesterone concentrations, with a time lag of approximately 16 h. Faecal progestin concentrations corresponded with the presence of functional CL and proved useful for monitoring luteal function, spontaneous and prostaglandin-F-2 alpha analogue-induced luteolysis and anovulation. In summary, faecal steroid monitoring is a practical, noninvasive method for characterising ovarian steroid excretion and has potential for facilitating the application of assisted reproductive technologies in scimitar-horned oryx. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. George Mason Univ, Fairfax, VA 22030 USA. RP Morrow, CJ (reprint author), Ruakura Agr Ctr, Anim Behav & Welf Res Ctr, Private Bag 3123, Hamilton, New Zealand. NR 31 TC 27 Z9 28 U1 0 U2 2 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 OCT PY 1998 VL 53 IS 1-4 BP 191 EP 207 DI 10.1016/S0378-4320(98)00113-4 PG 17 WC Agriculture, Dairy & Animal Science; Reproductive Biology SC Agriculture; Reproductive Biology GA 137KH UT WOS:000076913600015 PM 9835376 ER PT J AU Gunasena, KT Lakey, JRT Villines, PM Bush, M Raath, C Critser, ES McGann, LE Critser, JK AF Gunasena, KT Lakey, JRT Villines, PM Bush, M Raath, C Critser, ES McGann, LE Critser, JK TI Antral follicles develop in xenografted cryopreserved african elephant (Loxodonta africana) ovarian tissue SO ANIMAL REPRODUCTION SCIENCE LA English DT Article DE cryopreservation; ovarian tissue; elephant; xenograft ID FOLLICULAR DEVELOPMENT; MOUSE OVARIES; TRANSPLANTATION; SURVIVAL; OOCYTES; MICE AB The preservation of germ plasm from endangered species could augment captive breeding programs aimed at maintaining genetic diversity. Mammalian female germ plasm (oocytes) is extremely difficult to collect and cryopreserve; however, a promising alternative is the cryopreservation of ovarian tissue. In the present study, athymic nude (nu/nu) Balb/C mice were used to evaluate in vivo viability of cryopreserved ovarian tissue from Institute of Cancer Research genotype (ICR) mice or elephants. Female mice were ovariectomized prior to transplant of cryopreserved-thawed ovarian tissue from ICR mice (n = 4) or elephants (n = 6), Control mice were sham operated (n = 4) or ovariectomized (n = 5). Transplants were in the ovarian bursa, enabling in vivo ovulation and pregnancies from allografts. Vaginal cytology was monitored daily, and the intervals between and duration of epithelial cells present in smears were evaluated. Appearance of epithelial cells in sham-operated and allografted mice were at intervals of 4.3 +/- 0.6 and 3.3 +/- 0.5 days, lasting for 1.4 +/- 0.1 and 1.6 +/- 0.2 days, respectively. Sporadic incidence of epithelial cells in ovariectomized animals occurred at longer intervals (8.6 +/- 3.8 days). Females with xenografted elephant ovarian tissue demonstrated epithelial cells in vaginal smears at intervals of 4.5 +/- 1.0 days, for 2.5 +/- 0.5 days duration, which was significantly longer than the other groups (P < 0.05). Histological evaluation of tissues at the time of epithelial cells in smears demonstrated well-developed antral follicles, although oocytes were of poor morphological appearance or only cumulus-like complexes were seen. The nude mouse model is effective for assessing cryopreserved ovarian tissue xenograft function which can support the development of antral follicles. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Methodist Hosp Indiana, Adv Fertil Inst, Indianapolis, IN 46280 USA. Indiana Univ, Cryobiol Res Inst, Indianapolis, IN 46202 USA. Smithsonian Inst, Natl Zool Pk, NOAHS, Conservat & Res Ctr, Front Royal, VA 22630 USA. Kruger Natl Pk, ZA-1350 Skukuza, South Africa. Univ Alberta, Dept Lab Med & Pathol, Edmonton, AB, Canada. Biodivers Res Inst, Carmel, IN 46033 USA. RP Critser, JK (reprint author), Methodist Hosp Indiana, Adv Fertil Inst, 201 Penn Pkwy, Indianapolis, IN 46280 USA. EM critser@iquest.net FU NICHD NIH HHS [K04-HD00980] NR 19 TC 46 Z9 50 U1 1 U2 3 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 OCT PY 1998 VL 53 IS 1-4 BP 265 EP 275 DI 10.1016/S0378-4320(98)00132-8 PG 11 WC Agriculture, Dairy & Animal Science; Reproductive Biology SC Agriculture; Reproductive Biology GA 137KH UT WOS:000076913600020 PM 9835381 ER PT J AU Gilmore, JA McGann, LE Ashworth, E Acker, JP Raath, JP Bush, M Critser, JK AF Gilmore, JA McGann, LE Ashworth, E Acker, JP Raath, JP Bush, M Critser, JK TI Fundamental cryobiology of selected African mammalian spermatozoa and its role in biodiversity preservation through the development of genome resource banking SO ANIMAL REPRODUCTION SCIENCE LA English DT Article DE biodiversity; cryopreservation; permeability ID BOAR SPERMATOZOA; MORPHOLOGY; MOTILITY; REMOVAL; VOLUME; SEMEN AB Fundamental cryobiological characteristics of spermatozoa from threatened or endangered species must be determined for successful cryopreservation techniques to be established. In this study, spermatozoa from four diverse species, impala (Aepyceros melampus), wart hog (Phacochoerus aethiopicus), elephant (Loxodonta africana), and lion (Panthera lee), were collected by electroejaculation or epididymal aspiration. Spermatozoal plasma membrane permeability to water (hydraulic conductivity, L-p) and the osmotically inactive fraction of the sperm cell (V-b) were determined from each species. Changes in cell volume were measured over time using an electronic particle counter. A Kedem-Katchalsky membrane transport model was used to theoretically characterize the data to determine L-p and V-b for each species. In addition to determining plasma membrane characteristics, spermatozoa were also studied to determine their sensitivity to low temperatures and to permeating cryoprotectant solutes. Cells maintained at room temperature (20-22 degrees C) were slowly or rapidly exposed to cold temperatures (1-4 degrees C), and percent motility was estimated to determine the sensitivity of the cells to cooling. Spermatozoa were also in media containing 1 M glycerol, dimethyl sulfoxide or ethylene glycol, and percent motility was measured at 15, 30 and 60 min intervals to determine the sensitivity of the cells to the cryoprotectant agent over time. Results indicate that sperm motility is significantly effected by decreased temperatures and the presence of cryoprotectant agents. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Purdue Univ, Sch Vet Med, Biodivers Res Inst, W Lafayette, IN 47907 USA. Purdue Univ, Sch Vet Med, Cryobiol Res Inst, W Lafayette, IN 47907 USA. Purdue Univ, Sch Vet Med, Dept Vet Clin Sci, W Lafayette, IN 47907 USA. Univ Alberta, Dept Lab Med & Pathol, Edmonton, AB T6G 2R7, Canada. Purdue Univ, Ctr Plant Environm Stress Physiol, W Lafayette, IN 47907 USA. Kruger Natl Pk, Vet Serv, Skukuza, South Africa. Smithsonian Inst, Conservat Ctr, NOAHS, Front Royal, VA 22630 USA. RP Critser, JK (reprint author), Purdue Univ, Sch Vet Med, Biodivers Res Inst, W Lafayette, IN 47907 USA. EM critser@iquest.net FU PHS HHS [K04-00980] NR 35 TC 44 Z9 46 U1 0 U2 3 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 OCT PY 1998 VL 53 IS 1-4 BP 277 EP 297 DI 10.1016/S0378-4320(98)00118-3 PG 21 WC Agriculture, Dairy & Animal Science; Reproductive Biology SC Agriculture; Reproductive Biology GA 137KH UT WOS:000076913600021 PM 9835382 ER PT J AU Creel, S Creel, NM Monfort, SL AF Creel, S Creel, NM Monfort, SL TI Birth order, estrogens and sex-ratio adaptation in African wild dogs (Lycaon pictus) SO ANIMAL REPRODUCTION SCIENCE LA English DT Article DE sex ratio; estrogens; maternal parity; cooperative breeding; African wild dog; Lycaon pictus ID DOMINANCE; SELECTION; SUCCESS AB Because the sex of mammals is chromosomally determined, populations generally produce a similar proportion of males and females. However, it has been recognized for more than century that individuals might increase their fitness by over-producing offspring of one sex, under certain conditions. Small biases in the secondary sex ratio are seen in many vertebrates. Here, we report that the sex ratio of primiparous African wild dogs (Lycaon pictus) is strongly biased in favor of sons (63%), while multiparous females produce an excess of daughters (64%). The direction of these biases is predicted by individual females' need for subordinate helpers. For humans, elevated estrogens have been hypothesized to bias the secondary sex ratio toward males. Consistent with this hypothesis, primiparous female wild dogs had basal estrogen levels double those of multiparous females. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Montana State Univ, Dept Biol, Bozeman, MT 59717 USA. Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Creel, S (reprint author), Montana State Univ, Dept Biol, 310 Lewis Hall, Bozeman, MT 59717 USA. NR 22 TC 30 Z9 31 U1 2 U2 19 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 OCT PY 1998 VL 53 IS 1-4 BP 315 EP 320 DI 10.1016/S0378-4320(98)00121-3 PG 6 WC Agriculture, Dairy & Animal Science; Reproductive Biology SC Agriculture; Reproductive Biology GA 137KH UT WOS:000076913600024 PM 9835385 ER PT J AU Barton, EJ De Carvalho, RR Geller, MJ AF Barton, EJ De Carvalho, RR Geller, MJ TI Environments of redshift survey compact groups of galaxies SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : clusters : general; galaxies : distances and redshifts; galaxies : interactions ID PISCES-PERSEUS SUPERCLUSTER; CLASSIFICATION REVISED RS; 21 CM SURVEY; ABELL CLUSTERS; 21-CM SURVEY; ZONE; +21.5-DEGREES; +27.5-DEGREES; +33.5-DEGREES; POPULATIONS AB Redshift survey compact groups (RSCGs) are tight knots of N greater than or equal to 3 galaxies selected from the CfA2 + SSRS2 redshift survey. The selection is based on physical extent and association in redshift space alone. We measured 300 new redshifts of fainter galaxies within 1 h(-1) Mpc of 14 RSCGs to explore the relationship between RSCGs and their environments. Thirteen of 14 RSCGs are embedded in overdense regions of redshift space. The systems range from a loose group of five members to an Abell cluster. The remaining group, RSCG 64, appears isolated. RSCGs are isolated and distinct from their surroundings to varying degrees, as are the Hickson compact groups. Among the 13 embedded RSCGs, three are distinct from their general environments (RSCG 9, RSCG 11, and RSCG 85). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Observ Nacl, Dept Astrofis, BR-20921400 Sao Cristovao, RJ, Brazil. RP Barton, EJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 56 TC 28 Z9 28 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 1998 VL 116 IS 4 BP 1573 EP 1590 DI 10.1086/300531 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 128NP UT WOS:000076413100005 ER PT J AU Pahre, MA Djorgovski, SG de Carvalho, RR AF Pahre, MA Djorgovski, SG de Carvalho, RR TI Near-infrared imaging of early-type galaxies. III. The near-infrared fundamental plane SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : elliptical and lenticular, cD; galaxies : fundamental parameters; galaxies : photometry; galaxies : stellar content; infrared radiation ID ABSOLUTE MAGNITUDE RELATION; CCD SURFACE PHOTOMETRY; PERSEUS-PISCES REGION; ELLIPTICAL GALAXIES; VELOCITY DISPERSIONS; S0 GALAXIES; IR PHOTOMETRY; LOCAL GROUP; CLUSTERS; VIRGO AB Near-infrared imaging data on 251 early-type galaxies in clusters and groups are used to construct the near-infrared fundamental plane (FP) r(eff) proportional to sigma(0)(1.53+/-0.08) [Sigma(K)](eff)(-0.79+/-0.03) The slope of the FP therefore departs from the virial expectation of r(eff) proportional to sigma(0)(2)[Sigma](eff)(-1) at all optical and near-infrared wavelengths, which could be a result of the variation of MIL along the elliptical galaxy sequence or a systematic breakdown of homology among the family of elliptical galaxies. The slope of the near-infrared FP excludes metallicity variations as the sole cause of the slope of the FP. Age effects, dynamical deviations from a homology, or any combination of these (with or without metallicity), however, are not excluded. The scatter of both the near-infrared and optical FP are nearly identical and substantially larger than the observational uncertainties, demonstrating small but significant intrinsic cosmological scatter for the FP at all wavelengths. The lack of a correlation of the residuals of the near-infrared FP and the residuals from the Mg-2-sigma(0) relation indicates that the thickness of these relations cannot be ascribed only to age or metallicity effects. Because of this metallicity independence, the small scatter of the near-infrared FP excludes a model in which age and metallicity effects "conspire" to keep the optical FP thin. All of these results suggest that the possible physical origins of the FP relations are complicated due to combined effects of variations of stellar populations and structural parameters among elliptical galaxies. C1 CALTECH, Palomar Observ, Pasadena, CA 91125 USA. RP Pahre, MA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, MS 20, Cambridge, MA 02138 USA. NR 53 TC 137 Z9 137 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 1998 VL 116 IS 4 BP 1591 EP 1605 DI 10.1086/300544 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 128NP UT WOS:000076413100006 ER PT J AU Pahre, MA de Carvalho, RR Djorgovski, SG AF Pahre, MA de Carvalho, RR Djorgovski, SG TI Near-infrared imaging of early-type galaxies. IV. The physical origins of the fundamental plane scaling relations SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : elliptical and lenticular, cD; galaxies : evolution; galaxies : fundamental parameters; galaxies : photometry; galaxies : stellar content; infrared radiation ID COLOR-MAGNITUDE RELATION; CCD SURFACE PHOTOMETRY; PERSEUS-PISCES REGION; ELLIPTIC GALAXIES; PRECISION PHOTOMETRY; STELLAR POPULATIONS; SAMPLE SELECTION; VIRGO CLUSTERS; SPECTROSCOPY; GRADIENTS AB The physical origins of the fundamental plane (FP) scaling relations are investigated using large samples of early-type galaxies observed at optical and near-infrared wavelengths. The slope a in the FP relation r(eff) proportional to sigma(0)(a) [Sigma](eff)(b) is shown to increase systematically with wavelength from the U band (lambda similar to 0.35 mu m) through the K band (lambda similar to 2.2 mu m). A distance-independent construction of the observables is described that provides an accurate measurement of the change in the FP slope between any pair of bandpasses. The variation of the FP slope with wavelength is strong evidence of systematic variations in stellar content along the elliptical galaxy sequence, but is insufficient to discriminate between a number of simple models for possible physical origins of the FP. The intercept of the diagnostic relationship between log D-K/D-V and log sigma(0) shows no significant dependence on environment within the uncertainties of the Galactic extinction corrections, demonstrating the universality of the stellar population contributions at the level of Delta(V-K) = 0.03 mag to the zero point of the global scaling relations. Several other constraints on the properties of early-type galaxies-the slope of the Mg-2-sigma(0) relation, the slope of the FP in the K band, the effects of stellar population gradients, and the effects of deviations of early-type galaxies from a dynamically homologous family-are included to construct an empirical, self-consistent model that provides a complete picture of the underlying physical properties that are varying along the early-type galaxy sequence. The fundamental limitations to providing accurate constraints on the individual model parameters (variations in age and metallicity, and the size of the homology breaking) appear to be subtle variations between stellar population synthesis models and poorly constrained velocity dispersion aperture effects. This empirical approach nonetheless demonstrates that there are significant systematic variations in both age and metallicity along the elliptical galaxy sequence, and that a small, but systematic, breaking of dynamical homology (or a similar, wavelength-independent effect) is required. The intrinsic thickness of the FP can then be easily understood as small variations in age and metallicity, as well as deviations from a homology at any particular point along the FP. The model parameters will be better constrained by measurements of the change of the slope of the FP with redshift; predictions for this evolution with redshift are described. This model for the underlying physical properties that produce the FP scaling relations provides a comprehensive framework for future investigations of the global properties of early-type galaxies and their evolution. C1 CALTECH, Palomar Observ, Pasadena, CA 91125 USA. CNPq, Observ Nacl, Dept Astrofis, BR-20921030 Sao Cristovao, RJ, Brazil. RP Pahre, MA (reprint author), Harvard Smithsonian Ctr Astrophys, Mail Stop 20,60 Garden St, Cambridge, MA 02138 USA. NR 69 TC 105 Z9 106 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 1998 VL 116 IS 4 BP 1606 EP 1625 DI 10.1086/300545 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 128NP UT WOS:000076413100007 ER PT J AU Hillenbrand, LA Strom, SE Calvet, N Merrill, KM Gatley, I Makidon, RB Meyer, MR Skrutskie, MF AF Hillenbrand, LA Strom, SE Calvet, N Merrill, KM Gatley, I Makidon, RB Meyer, MR Skrutskie, MF TI Circumstellar disks in the Orion Nebula Cluster SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : open clusters and associations; stars : circumstellar matter; stars : formation; stars : pre-main-sequence ID T-TAURI STARS; MAIN-SEQUENCE STARS; HERBIG AE/BE STARS; YOUNG STARS; ACCRETION DISKS; MAGNETOSPHERIC ACCRETION; INFRARED PHOTOMETRY; EMISSION; RESOLUTION; MODEL AB We combine our previous optical spectroscopic and photometric analysis of similar to 1600 stars located in the Orion Nebula Cluster (ONC) with our own and published near-infrared photometric surveys of the region in order to investigate the evidence for and properties of circumstellar disks. We use the near-infrared continuum excess as our primary disk diagnostic, although we also study sources with Ca II triplet emission and those designated as "proplyds." The measured near-infrared excess is influenced by (1) the presence or absence of a circumstellar disk, (2) the relative importance of disk accretion and inner disk holes, (3) the relative contrast between photospheric and disk emission, and (4) system inclination. After attempting to understand the effects of these influences, we estimate the frequency of circumstellar disks and discuss the evidence for trends in the disk frequency with stellar mass (over the mass range < 0.1-50 M-.), stellar age (over the age range < 0.1-2 Myr), and projected cluster radius (over the radial range 0-3 pc). We find that the fraction of stars retaining their inner (< 0.1 AU) circumstellar disks to the present time is at least 55% and probably no more than 90%, averaged over the entire range in stellar mass and stellar age represented in the ONC and over the entire area of our survey. We find no trend in the disk fraction with stellar age, at least not over the limited age range of the cluster. We find that more massive stars are less likely to have disks, consistent with a scenario in which the evolutionary timescales are more rapid for disks surrounding more massive stars than for disks surrounding less massive stars. We also find that the disk frequency begins to decrease toward the lowest masses, although objects of all masses (including those that appear to be substellar) can have disks. We find that the disk frequency increases toward the cluster center. We then argue, using several lines of evidence, that a large fraction of the disks associated with stars in the ONC are accretion disks. The observed trends with stellar age, stellar mass, and projected cluster radius in the disk frequency may, in fact, be driven primarily by trends in the disk accretion properties. From the magnitude of the near-infrared excess above that expected from pure irradiation disks, we find an accretion disk fraction among the stars identified as having disks of 61%-88%. In addition, approximately 20% of the stars in our optical spectroscopic sample show broad (several hundred km s(-1) FWHM) Ca II emission lines, which are features often associated with accretion disk/wind phenomena; another 50% of the sample have Ca II lines that (at our spectral resolution) are "filled in," indicating an independently derived accretion disk frequency of similar to 70%. Finally, we discuss the near-infrared and optical emission-line properties of that portion of our sample identified from Hubble Space Telescope imaging as having a dark silhouette or an externally ionized structure. This sample, proposed in the literature to have accretion disks, appears to be no different in terms of its stellar or circumstellar properties from the rest of the ONC population. The only feature distinguishing these objects from their ONC siblings thus may be their current (but short-lived) proximity to the massive stars near the cluster center. C1 CALTECH, Dept Astron, Pasadena, CA 91125 USA. Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Kitt Peak Natl Observ, Tucson, AZ 85726 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Hillenbrand, LA (reprint author), CALTECH, Dept Astron, MS 105-24, Pasadena, CA 91125 USA. NR 62 TC 197 Z9 197 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 1998 VL 116 IS 4 BP 1816 EP 1841 DI 10.1086/300536 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 128NP UT WOS:000076413100027 ER PT J AU Olsen, EL Leer, E Lie-Svendsen, O AF Olsen, EL Leer, E Lie-Svendsen, O TI An eight-moment model parameter study of the solar wind: dependence on variations in coronal heating SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : corona; solar wind ID FLUX-TUBE DIVERGENCE; ENERGY-BALANCE; 2-FLUID MODEL; ACCELERATION; SPEED; FLOW; HOLE AB The eight-moment two-fluid model describes, self-consistently, the proton (and electron) heat flux in the solar wind. This is a crucial parameter in solar wind models with a high coronal proton temperature. In the present study the eight-moment description is used to study how the solar wind outflow from an electron-proton corona responds to variations in coronal heating. Most of the energy flux is deposited in the proton gas. We find that the asymptotic flow speed of the solar wind is only weakly dependent on the amplitude of the energy flux, but it increases with increasing dissipation length. When most of the energy flux is dissipated in the extended corona, where the protons are collisionless, we obtain flow speeds characteristic of high-speed solar wind streams: For a dissipation length of 1 to 2 solar radii the asymptotic flow speed is 700-1000 km s(-1) A relatively modest electron heating in the inner corona may lead to an increased transition region pressure and hence a large increase in the solar wind proton flux. This increase in proton flux may be so large that there is not enough energy available to drive a high-speed wind. C1 Univ Oslo, Inst Theoret Astrophys, N-0315 Oslo, Norway. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Norwegian Def Res Estab FFI, Div Elect, N-2007 Kjeller, Norway. RP Leer, E (reprint author), Univ Oslo, Inst Theoret Astrophys, POB 1029, N-0315 Oslo, Norway. EM elols@statoil.no; egil.leer@astro.uio.no; Oystein.Lie-Svendsen@ffi.no NR 26 TC 9 Z9 9 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD OCT PY 1998 VL 338 IS 2 BP 747 EP 755 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 132CF UT WOS:000076611900044 ER PT J AU Grogin, NA Geller, MJ AF Grogin, NA Geller, MJ TI Ly alpha absorption systems and the nearby galaxy distribution SO ASTROPHYSICAL JOURNAL LA English DT Article DE intergalactic medium; large-scale structure of universe; quasars : absorption lines ID CFA REDSHIFT SURVEY; LUMINOSITY FUNCTION; LYMAN; CLOUDS; SCALE; QSOS; MINIHALOES; EVOLUTION; SPECTRA; ORIGIN AB We study the galaxy number density (smoothed on a 5 h(-1) Mpc scale) around 18 low-redshift Ly alpha absorbers previously observed with HST. The absorbers lie in the foregrounds of Mrk 335, Mrk 421, Mrk 501, I Zw 1, and 3C 273, all within regions where there are now complete redshift surveys to m(zw) = 15.5. We construct a smoothed galaxy number density held from the redshift survey data and determine the distribution of densities at the Ly alpha absorber locations. We also find the distribution of galaxy number density for a variety of test samples: all galaxy locations within the Center for Astrophysics Redshift Survey (CfA2), CfA2 galaxy locations along randomly selected lines of sight, and randomly chosen redshifts along random lines of sight. The Ly alpha absorbers are present in dense regions of the survey, but occur far more frequently in underdense regions than do typical luminous galaxies. The distribution of smoothed galaxy density around the Ly alpha absorbers is inconsistent at the 4 sigma level with the density distribution around survey galaxies. It is highly consistent with a density distribution at randomly chosen redshifts along random lines of sight. This supports earlier evidence that the nearby, low column density (log N(HI) less than or similar to 14) Ly alpha forest systems are spatially distributed at random; they are not well correlated with the local large-scale structure. 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 46 TC 34 Z9 34 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1998 VL 505 IS 2 BP 506 EP 518 DI 10.1086/306208 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500003 ER PT J AU Torrelles, JM Gomez, JF Rodriguez, LF Curiel, S Anglada, G Ho, PTP AF Torrelles, JM Gomez, JF Rodriguez, LF Curiel, S Anglada, G Ho, PTP TI Radio continuum-H2O maser systems in NGC 2071: H2O masers tracing a jet (IRS 1) and a rotating proto-planetary disk of radius 20 AU (IRS 3) SO ASTROPHYSICAL JOURNAL LA English DT Article DE H II regions; ISM : individual (NGC 2071); ISM : jets and outflows; masers; stars : formation ID SHOCKED MOLECULAR-HYDROGEN; VLA OBSERVATIONS; INFRARED SOURCES; HIGH-RESOLUTION; WATER MASERS; NGC-2071; OUTFLOW; STAR; EMISSION; REGIONS AB We have observed simultaneously the 1.3 cm continuum and H2O maser emission toward the core of the star-forming region NGC 2071 using the Very Large Array in its A configuration. Two 1.3 cm continuum sources have been detected in the region, coinciding with the infrared sources IRS 1 and IRS 3, respectively. The radio emission in IRS 3 is consistent with an ionized thermal bipolar radio jet. Two clusters of H2O maser spots are detected, one associated with IRS 1 (22 spots) and the other one associated with IRS 3 (13 spots). The H2O maser distribution in IRS I seems to be tracing at scales of 300 AU the larger scale H-2 outflow observed at a few thousands of AU from the exciting source. On the other hand, the H2O masers in IRS 3 are distributed as an apparent disk of similar or equal to 0." 05 (similar or equal to 20 AU) radius, oriented almost perpendicular to the major axis of the radio jet. There is a clear velocity gradient (similar or equal to 0.35 km s(-1) AU(-1)) along the major axis of the H2O maser distribution, which can be gravitationally bound by a central mass of similar or equal to 1 M-.. These results, together with the low-mass and early evolutionary stage of IRS 3, suggest that masers around this source are tracing a rotating proto-planetary disk within a proto-solar-like system. This represents direct kinematic evidence of the smallest rotating circumstellar disk ever observed around a young stellar object (YSDO). We discuss the dichotomy of H2O masers tracing either outflows or disks around YSOs, based on the evolutionary scheme proposed in our earlier work. We suggested that systems in which H2O masers trace disks are less evolved than those in which masers trace outflows. In this scheme, IRS 3 would then represent a relatively less-evolved object than IRS 1. This prediction is consistent with independent infrared observations showing that IRS 3 is at an earlier phase of evolution. C1 CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Inst Nacl Techn Aerospacial, Lab Astrofis Espacial & Fis Fundamental, E-28080 Madrid, Spain. Natl Autonomous Univ Mexico, Inst Astron, Mexico City 04510, DF, Mexico. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Torrelles, JM (reprint author), Univ Illes Balears, CSIC, Inst Mediterraneo Estudios Avanzados, Apartado Correos 3004, E-07071 Palma de Mallorca, Spain. RI Gomez, Jose Francisco/D-8392-2016; OI Gomez, Jose Francisco/0000-0002-7065-542X; Torrelles, Jose Maria/0000-0002-6896-6085 NR 51 TC 70 Z9 70 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1998 VL 505 IS 2 BP 756 EP 765 DI 10.1086/306205 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500022 ER PT J AU Yi, IS Grindlay, JE AF Yi, IS Grindlay, JE TI Spin-up of low-luminosity, low-mass X-ray binaries SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; pulsars : general; stars : magnetic fields; X-rays : stars ID ACCRETION-INDUCED COLLAPSE; MILLISECOND PULSARS; GLOBULAR-CLUSTERS; NEUTRON-STARS; WHITE-DWARFS; DISK; TRANSIENTS; ORIGIN; BURST; BIRTH AB We examine the spin-up of low;luminosity, low-mass X-ray binaries (LMXBs) to millisecond pulsars (MSPs). In the conventional spin-up model of the Ghosh & Lamb type, where the stellar magnetic field interacts with the Keplerian accretion disk, MSPs could be produced from LMXBs if the magnetic field B* less than or similar to 10(8)((M) over dot/10(16) g s(-1)) G, where (M) over dot is the mass accretion rate. However, for (M) over dot < (M) over dot(c) similar to 10(16) g s(-1) accretion is likely to occur via a quasi-spherical flow with a sub-Keplerian rotation. The sub-Keplerian rotation rate is smaller than the Keplerian rate by a factor similar to 2-10. As a consequence, the spin up of LMXBs produces pulsars with spin periods longer by a factor of similar to 2-10 than those with a Keplerian accretion disk. The observed MSPs could be produced only for B* < 10(7) G even when (M) over dot similar to (M) over dot(c) similar to 10(16) g s(-1). This suggests that the low-luminosity LMXBs with (M) over dot < (M) over dot(c) would not be able to spin-up to the observed MSPs. This rules out any undetected populations of persistent, low-luminosity LMXBs and a potentially significant fraction of the atoll sources as a possible source population of the observed MSPs. If a large number of undetected, persistent, low-luminosity LMXBs do exist, they could produce MSPs near the pulsar death Line with intrinsic electromagnetic luminosity less than or similar to 10(30) ergs s(-1). The observed MSPs could possibly arise from a population of soft X-ray transients (SXTs) containing neutron stars, although this is not supported by current estimates of the outburst rate or numbers of such systems. Accretion-induced collapse of low magnetic field white dwarfs remains a possible channel for MSP formation. C1 Inst Adv Study, Princeton, NJ 08540 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Ewha Womans Univ, CAIS RIBs, Seoul 120750, South Korea. Ewha Womans Univ, Dept Phys, Seoul 120750, South Korea. RP Yi, IS (reprint author), Inst Adv Study, Olden Lane, Princeton, NJ 08540 USA. NR 38 TC 6 Z9 6 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 OCT 1 PY 1998 VL 505 IS 2 BP 828 EP 834 DI 10.1086/306193 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500026 ER PT J AU Esin, AA Narayan, R Cui, W Grove, JE Zhang, SN AF Esin, AA Narayan, R Cui, W Grove, JE Zhang, SN TI Spectral transitions in Cygnus X-1 and other black hole X-ray binaries SO ASTROPHYSICAL JOURNAL LA English DT Review DE accretion, accretion disks; black hole physics; stars : individual (Cygnus X-1, GRO J0422+32, GRO J1719-24); X-rays : stars ID ADVECTION-DOMINATED ACCRETION; ACTIVE GALACTIC NUCLEI; 226868 = CYGNUS-X-1; NOVA-MUSCAE 1991; HDE 226868; GRO J0422+32; DISK MODEL; OPTICAL COUNTERPART; SPHERICAL ACCRETION; INTERMEDIATE STATE AB We show that the model proposed by Esin, McClintock, & Narayan for the low state, intermediate stale, and high state of the black hole soft X-ray transient, Nova Muscae 1991, is consistent with the spectral evolution of the black hole X-ray binary, Cyg X-1, during the hard-to-soft slate transition observed in 1996. We also apply the model to the outbursts of two other black hole X-ray transients, GRO J0422 + 32 and GRO J1719 - 24. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. USN, Res Lab, Washington, DC 20375 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Esin, AA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 120 TC 205 Z9 208 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1998 VL 505 IS 2 BP 854 EP 868 DI 10.1086/306186 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500029 ER PT J AU Mauche, CW Raymond, JC AF Mauche, CW Raymond, JC TI ORFEUS II far-ultraviolet spectroscopy of AM Herculis SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; stars : individual (AM Herculis); stars : magnetic fields; ultraviolet : stars; white dwarfs ID X-RAY; WHITE-DWARF; IUE; ACCRETION AB Six high-resolution (lambda/Delta lambda approximate to 3000) far-UV (lambda lambda = 910-1210 Angstrom) spectra of the magnetic cataclysmic variable AM Herculis were acquired in 1996 November during the flight of the ORFEUS-SPAS II mission. AM Her was in a high optical state at the time of the observations, and the spectra reveal emission lines of O VI lambda lambda 1032, 1038, C III lambda lambda 977, 1176, and He II lambda 1085 superposed on a nearly flat continuum. Continuum flux variations can be described as per Gansicke et al. by a approximate to 20 kK white dwarf with a approximate to 37 kK hot spot covering a fraction f similar to 0.15 of the surface of the white dwarf, but we caution that the expected Lyman absorption lines are not detected. The O VI emission lines have a broad and narrow component structure similar to that of the optical emission lines, the C III and He II emission lines are dominated by the broad component, and the radial velocities of these lines are consistent with an origin of the narrow and broad components in the irradiated face of the secondary and the accretion funnel, respectively. The density of the narrow- and broad-line regions is n(nlr) similar to 3 x 10(10) cm(-3) and n(blr) similar to 1 x 10(12) cm(-3) respectively, yet the narrow-line region is optically thick in the O VI line and the broad-line region is optically thin; apparently, the velocity shear in the broad-line region allows the O VI photons to escape, rendering the gas effectively optically thin. The orbital phase variations of the emission-line fluxes are unexplained. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Mauche, CW (reprint author), Lawrence Livermore Natl Lab, L-41,POB 808, Livermore, CA 94550 USA. EM mauche@cygnus.llnl.gov; jraymond@cfa.harvard.edu NR 31 TC 15 Z9 15 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1998 VL 505 IS 2 BP 869 EP 875 DI 10.1086/306185 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500030 ER PT J AU Bohm-Vitense, E Evans, NR Carpenter, K Albrow, MD Cottrell, PL Robinson, R Beck-Winchatz, B AF Bohm-Vitense, E Evans, NR Carpenter, K Albrow, MD Cottrell, PL Robinson, R Beck-Winchatz, B TI The mass of the Cepheid binary V636 Scorpii SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : spectroscopic; Cepheids; stars : evolution; stars : individual (V636 Scorpii) ID DYNAMICAL MASS; S-MUSCAE; STARS; MODELS; ORBIT AB The mass-luminosity relation for Cepheids depends on the degree of mixing in their main-sequence progenitors. Masses of Cepheids can be inferred by using different aspects of pulsation theory. These methods have in the past led to diverging results, showing that something was wrong in either evolution theory or pulsation theory or both. For some binary Cepheids dynamical masses, which are independent of pulsation and evolution theories, can be determined. V636 Sco is one of a handful of Cepheid binaries whose companions are bright enough in the ultraviolet that orbital radial velocities can be measured. We have here attempted to determine the radial velocity of the companion V636 Sco B to the Cepheid V636 Sco A by means of two Hubble Space Telescope (HST) spectra taken at phases of minimum and maximum Cepheid orbital velocities. The ratio of the orbital velocity of the companion and the Cepheid (which is the inverse of their mass ratio) came out to be 1.25 +/- 0.17. V636 Sco B has a spectral type B9.5 V, for which we expect a stellar mass of 2.5 M-.. For the Cepheid we thus determine a mass of 3.1 +/- 0.4 Mo, which is surprisingly low. If true, such a low mass would indicate an extremely large amount of excess mixing, which is very unlikely. We discuss the likely possibility that V636 Sco B may itself be a binary with an unseen secondary, in which case the mass derived from the two measurements discussed above is not correct. Although the error limits for the mass of each Cepheid are rather large, the combined mass-luminosity relation for all Cepheids studied by us so far by means of HST spectra indicates excess mixing corresponding to core convective overshoot by 0.25 to about 0.5 pressure scale height in the main-sequence progenitors of the Cepheids. C1 Univ Washington, Dept Astron, Seattle, WA 98195 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Astron & Solar Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Canterbury, Dept Phys & Astron, Mt John Univ Observ, Christchurch 1, New Zealand. S African Astron Observ, ZA-7935 Cape Town, South Africa. Comp Sci Corp, Greenbelt, MD 20771 USA. RP Bohm-Vitense, E (reprint author), Univ Washington, Dept Astron, Seattle, WA 98195 USA. EM erica@astro.washington.edu; evans@cfambl.harvard.edu; hrscarpenter@tmal.gasfc.nasa.gov; cottrell@cantva.canterbury.ac.nz; hrsrobinson@tmal.gsfc.nasa.gov RI Carpenter, Kenneth/D-4740-2012 NR 28 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 OCT 1 PY 1998 VL 505 IS 2 BP 903 EP 909 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500033 ER PT J AU Dmitruk, P Gomez, DO DeLuca, EE AF Dmitruk, P Gomez, DO DeLuca, EE TI Magnetohydrodynamic turbulence of coronal active regions and the distribution of nanoflares SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; Sun : corona; Sun : flares; turbulence ID SOLAR CORONA; FLARE PARAMETERS; LINE WIDTHS; DYNAMICS; ENERGY; LOOPS; FIELDS AB We present results from numerical simulations of an externally driven two-dimensional magnetohydrodynamic system over extended periods of time, used to model the dynamics of a transverse section of a solar coronal loop. A stationary forcing was imposed to model the photospheric motions at the loop footpoints. After several photospheric turnover times, a turbulent stationary regime is reached that has an energy dissipation rate consistent with the heating requirements of coronal loops. The turbulent velocities obtained in our simulations are consistent with those derived from the nonthermal broadening of coronal spectral lines. We also show the development of small scales in the spatial distribution of electric currents, which are responsible for most of the energy dissipation. The energy dissipation rate as a function of time displays an intermittent behavior, in the form of impulsive events, that is a direct consequence of the strong nonlinearity of the system. We associate these impulsive events of magnetic energy dissipation with the so-called nanoflares. A statistical analysis of these events yields a power-law distribution as a function of their energies with a negative slope of 1.5, consistent with those obtained for hare energy distributions reported from X-ray observations. A simple model of dissipative structures, based on Kraichnan's theory for MHD turbulence, is also presented. C1 Univ Buenos Aires, Fac Ciencias Exactas & Nat, Dept Fis, RA-1428 Buenos Aires, DF, Argentina. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Inst Astron & Fis Espacio, RA-1428 Buenos Aires, DF, Argentina. RP Univ Buenos Aires, Fac Ciencias Exactas & Nat, Dept Fis, Ciudad Univ,Pabellon 1, RA-1428 Buenos Aires, DF, Argentina. EM dmitruk@df.uba.ar RI DeLuca, Edward/L-7534-2013; OI DeLuca, Edward/0000-0001-7416-2895; Gomez, Daniel/0000-0002-4935-4358 NR 32 TC 72 Z9 72 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 OCT 1 PY 1998 VL 505 IS 2 BP 974 EP 983 DI 10.1086/306182 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500039 ER PT J AU Vikhlinin, A AF Vikhlinin, A TI A search for X-ray counterparts of gamma-ray bursts with the ROSAT PSPC SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; surveys; X-rays : bursts ID DIFFUSE AB We search for faint X-ray bursts with duration 10-300 s in the ROSAT PSPC pointed observations with a total exposure of 1.6 x 10(7) s. We do not detect any events shorter than similar to 100 s, i.e., those that could be related to the classic gamma-ray bursts (GRBs). At the same time, we detect a number of long flares with durations of several hundred seconds. Most, but not all, of the long flares are associated with stars. If even a small number of those long flares, which cannot be identified with stars, are X-ray afterglows of GRBs, the number of X-ray afterglows greatly exceeds the number of BATSE GRBs. This would imply that the beaming factor of gamma rays from the burst should be greater than 100. The nondetection of any short bursts in our data constrains the GRB counts at the fluences to 10-300 times fainter than the BATSE limit. The constrained burst counts are consistent with the extrapolation of the BATSE log N-log S relation. Finally, our results do not confirm the reality of short X-ray flashes found in the Einstein IPC data by Gotthelf, Hamilton, & Helfand. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Vikhlinin, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 16 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 OCT 1 PY 1998 VL 505 IS 2 BP L123 EP L126 DI 10.1086/311606 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LH UT WOS:000077778700013 ER PT J AU Zhang, QZ Hunter, TR Sridharan, TK AF Zhang, QZ Hunter, TR Sridharan, TK TI A rotating disk around a high-mass young star SO ASTROPHYSICAL JOURNAL LA English DT Article DE H II regions; ISM : clouds; ISM : individual (IRAS 20126+4104); ISM : kinematics and dynamics; stars : formation; stars : pre-main-sequence ID COLD IRAS SOURCES; CIRCUMSTELLAR DISKS; CORES; TAURI; LINE; GAS AB We report the discovery of a disk around the young high-mass star IRAS 20126+4104. Tn the NH3 (1, 1) and (2, 2) lines, we detected a flattened disklike structure (6 " x 3 " or 10,000 x 5000 AU) roughly perpendicular to a bipolar molecular outflow. A velocity gradient exists along the major axis of the disk. The disk rotates faster toward the center. Our findings provide direct verification that disks exist during the formation of high-mass stars. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Radio Astron Observ, Tucson, AZ 85721 USA. RP Zhang, QZ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Hunter, Todd/0000-0001-6492-0090; Zhang, Qizhou/0000-0003-2384-6589 NR 16 TC 95 Z9 96 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1998 VL 505 IS 2 BP L151 EP L154 DI 10.1086/311609 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LH UT WOS:000077778700020 ER PT J AU Lovette, IJ Bermingham, E Seutin, G Ricklefs, RE AF Lovette, IJ Bermingham, E Seutin, G Ricklefs, RE TI Evolutionary differentiation in three endemic West Indian Warblers SO AUK LA English DT Article ID MITOCHONDRIAL-DNA VARIATION; TREE TOPOLOGIES; BIOGEOGRAPHY; VERTEBRATES; GENE; CONSERVATION; PLEISTOCENE; SPECIATION; SEQUENCES; PHYLOGENY AB We explored the evolution of geographic distributions in archipelagos by comparing mitochondrial DNA (mtDNA) sequences and morphometric characters within and among conspecific populations of Adeiaide's Warbler (Dendroica adelaidae), Plumbeous Warbler (D. plumbea), and Olive-capped Warbler (D. pityophila). Phylogenetic reconstructions were based upon 1,455 nucleotides of protein-coding mtDNA sequence from 53 individual warblers; morphological analyses employed three external measurements from a larger number of museum specimens. Of the three taxa studied, Adeiaide's Warbler occupied the broadest and most fragmented geographical distribution and exhibited the greatest interpopulation differentiation in both mtDNA and morphology. Phylogenetic analyses demonstrated that the three Adeiaide's Warbler populations are each reciprocally monophyletic with the Puerto Rican lineage basal to sister clades on Barbuda and St. Lucia. Genetic distances among these populations were comparable with those between some continental species. In contrast to the mtDNA pattern, the Puerto Rican and Barbudan Adelaide's Warbler populations were most similar in morphometry. We observed considerably less mtDNA and morphometric differentiation among populations of the two species with more restricted and less fragmented distributions, the Plumbeous Warbler of Dominica and Guadeloupe and the Olive-capped Warbler of the Bahamas and Cuba. High levels of molecular and morphological differentiation among the geographically disjunct Adelaide's Warbler populations and low differentiation in the two species with less fragmented ranges suggest that range disjunctions indicate the long-term evolutionary independence of geographically isolated island populations. C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Penn, Dept Biol, Philadelphia, PA 19104 USA. McGill Univ, Dept Geog, Montreal, PQ H3A 2K6, Canada. Univ Missouri, Dept Biol, St Louis, MO 63121 USA. RP Lovette, IJ (reprint author), Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. RI Lovette, Irby/P-3477-2014 NR 64 TC 51 Z9 54 U1 0 U2 7 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 OCT PY 1998 VL 115 IS 4 BP 890 EP 903 PG 14 WC Ornithology SC Zoology GA 186LL UT WOS:000079730900009 ER PT J AU Isler, ML Rodner, C AF Isler, ML Rodner, C TI In memoriam: Betsy Trent Thomas, 1923-1998 SO AUK LA English DT Biographical-Item C1 Smithsonian Inst, Natl Museum Nat Hist, Div Birds, Washington, DC 20560 USA. Colecc Ornitol WH Phelps, Caracas 1080A, Venezuela. Soc Conservac Audubon Venezuela, Caracas 1080A, Venezuela. RP Isler, ML (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Div Birds, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 OCT PY 1998 VL 115 IS 4 BP 1052 EP 1052 PG 1 WC Ornithology SC Zoology GA 186LL UT WOS:000079730900022 ER PT J AU Pruski, JF AF Pruski, JF TI Compositae of the Guayana Highland - XIII. New combinations in Conyza (Astereae), Praxelis (Eupatorieae), and Riencourtia (Heliantheae) based on names proposed by L.C.M. Richard SO BRITTONIA LA English DT Article DE Asteraceae; Compositae; Conyza; French Guiana; Guayana; J. B. LeBlond; Praxelis; L. C. M. Richard; Riencourtia; West Indies AB The new combinations Conyza laevigata (Astereae), Praxelis diffusa (Eupatorieae), and Riencourtia pedunculosa (Heliantheae) are made. Conyza laevigata includes C. apurensis; Praxelis diffusa includes P. pauciflora and the type of the genus, P. villosa; and Riencourtia pedunculosa includes R. glomerata and R, spiculifera, the type of the genus. Lectotypes are designated for names of five species described by Richard. The current names of other species of Compositae described by Richard in 1792 are given, including the reduction of Eupatorium incisum to Chromolaena odorata. Labeling errors are discussed, and the type of Erigeron laevigatus is taken to be from the West Indies. Riencourtia is newly documented for Bolivia and Panama. C1 Smithsonian Inst, US Natl Herbarium, Dept Bot, Washington, DC 20560 USA. RP Pruski, JF (reprint author), Smithsonian Inst, US Natl Herbarium, Dept Bot, MRC-166, Washington, DC 20560 USA. NR 37 TC 1 Z9 1 U1 0 U2 1 PU NEW YORK BOTANICAL GARDEN PI BRONX PA PUBLICATIONS DEPT, BRONX, NY 10458 USA SN 0007-196X J9 BRITTONIA JI Brittonia PD OCT-DEC PY 1998 VL 50 IS 4 BP 473 EP 482 DI 10.2307/2807757 PG 10 WC Plant Sciences SC Plant Sciences GA 152CD UT WOS:000077757200007 ER PT J AU Acevedo-Rodriguez, P AF Acevedo-Rodriguez, P TI Paullinia lingulata (Sapindaceae), a new species from French Guiana SO BRITTONIA LA English DT Article DE Paullinia; Sapindaceae; French Guiana AB The new species Paullinia lingulata from French Guiana is described, illustrated, and compared with a vegetatively similar species found in French Guiana. C1 Smithsonian Inst, Natl Museum Amer Hist, Dept Bot, Washington, DC 20560 USA. RP Acevedo-Rodriguez, P (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Dept Bot, MRC-166, Washington, DC 20560 USA. NR 1 TC 4 Z9 4 U1 0 U2 0 PU NEW YORK BOTANICAL GARDEN PI BRONX PA PUBLICATIONS DEPT, BRONX, NY 10458 USA SN 0007-196X J9 BRITTONIA JI Brittonia PD OCT-DEC PY 1998 VL 50 IS 4 BP 514 EP 516 DI 10.2307/2807762 PG 3 WC Plant Sciences SC Plant Sciences GA 152CD UT WOS:000077757200012 ER PT J AU Takahahshi, E Nakajima, K Wright, TL AF Takahahshi, E Nakajima, K Wright, TL TI Origin of the Columbia River basalts: melting model of a heterogeneous plume head SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE basalts; flood basalts; magmas; mantle plumes; hot spots ID SUBDUCTED OCEANIC-CRUST; FLOOD BASALTS; MANTLE PLUMES; PERIDOTITE KLB-1; DRY PERIDOTITE; HIGH-PRESSURES; SNAKE RIVER; GENESIS; CONSTRAINTS; GENERATION AB In order to study the origin of the Grande Ronde basalts (GRs) erupted in the climax stage of the Columbia River basalts (CRBs), we carried out high pressure melting experiments on four of the most primitive rock compositions representing the Yakima group of the CRBs. The voluminous GRs (constituting >80 vol% of CRBs) are totally aphyric basaltic andesites. GRs show very narrow and coherent chemical trends both in major and trace elements as well as isotopes. The silica-rich GRs (SiO2 = 52-56 wt%) can be produced by direct partial melting of a MORE like source material (CRB72-31) at similar to 2 Cpa or similar to 70 lan depth. By 30-50% partial melting of the CRB72-31, the entire compositional range of the GRs can be produced in a narrow temperature interval (1300-1350 degrees C) at similar to 2 Cpa. The aluminous clinopyroxene that appears in the above melting range is consistent as the major controlling phase of the GR trends. The partial melts are very similar to the GRs except for Al2O3 and FeO which could be due to the mismatch in the source rock composition. Judging from the variation in REE, involvement of garnet in GR magma genesis can be ruled out. Small amounts of plagioclase (10-30 wt%) may be present in the partial melting residue. Judging from REE patterns and Nd isotopes of the GRs, the source rock should be unfractionated in REE. Based on the melting experiments, a heterogeneous plume model is proposed for the initial stage of the Yellowstone hot spot. Large lithologically distinct blobs of old oceanic crust components were included in the plume head. The GR magmas were produced by partial melting of the oceanic crust components at the bottom of the North American lithosphere. Similar melting processes of basalt/peridotite composite source may be operating in other LIPs (large igneous provinces). The GR type genuine oceanic crust derived melts may be seen where the ambient peridotite remains under subsolidus conditions. Volume and temperature of mantle plumes may have been overestimated, because contributions from the recycled oceanic crust is so large and the current mantle melting models concern only peridotite source. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Tokyo Inst Technol, Magma Factory, Meguro Ku, Tokyo 152, Japan. Smithsonian Inst, Washington, DC 20560 USA. RP Takahahshi, E (reprint author), Tokyo Inst Technol, Magma Factory, Meguro Ku, 2-12-1 Ookayama, Tokyo 152, Japan. EM etakahas@geo.titech.ac.jp RI Takahashi, Eiichi/B-4883-2017 OI Takahashi, Eiichi/0000-0002-6500-1827 NR 50 TC 140 Z9 149 U1 4 U2 25 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD OCT PY 1998 VL 162 IS 1-4 BP 63 EP 80 DI 10.1016/S0012-821X(98)00157-5 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 132QF UT WOS:000076640500005 ER PT J AU Cox, TM Read, AJ Barco, S Evans, J Gannon, DP Koopman, HN McLellan, WA Murray, K Nicolas, J Pabst, DA Potter, CW Swingle, WM Thayer, VG Touhey, KM Westgate, AJ AF Cox, TM Read, AJ Barco, S Evans, J Gannon, DP Koopman, HN McLellan, WA Murray, K Nicolas, J Pabst, DA Potter, CW Swingle, WM Thayer, VG Touhey, KM Westgate, AJ TI Documenting the bycatch of harbor porpoises, Phocoena phocoena, in coastal gillnet fisheries from stranded carcasses SO FISHERY BULLETIN LA English DT Article ID NET AB We examined 107 harbor porpoise (Phocoena phocoena) carcasses recovered from beaches in Maryland, Virginia, and North Carolina between 1994 and 1996 for evidence of entanglement in fishing gear. Stranded porpoises ranged in length from 102 to 128 cm, indicating that only juvenile porpoises are present in the nearshore waters of the Mid-Atlantic during winter. Of the 40 porpoises for which we could establish cause of death, 25 displayed definitive evidence of entanglement in fishing gear. Evidence of entanglement consisted primarily of line marks from nets; in four cases we were able to determine specifically that porpoises had become entangled in monofilament nets. These mortalities demonstrate the need for a directed observer program for coastal gillnet fisheries in the Mid-Atlantic. C1 Duke Univ, Marine Lab, Nicholas Sch Environm, Beaufort, NC 28516 USA. Virginia Marine Sci Museum, Virginia Beach, VA 23451 USA. Maryland Dept Nat Resources, Fisheries Serv, Cooperat Oxford Lab, Oxford, MD 21654 USA. Univ N Carolina, Wilmington, NC 28403 USA. NE Fisheries Sci Ctr, Woods Hole, MA 02543 USA. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. NOAA, Natl Marine Fisheries Serv, SE Fisheries Ctr, Beaufort Lab, Beaufort, NC 28516 USA. RP Cox, TM (reprint author), Duke Univ, Marine Lab, Nicholas Sch Environm, 135 Duke Marine Lab Rd, Beaufort, NC 28516 USA. NR 12 TC 21 Z9 24 U1 4 U2 8 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 USA SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD OCT PY 1998 VL 96 IS 4 BP 727 EP 734 PG 8 WC Fisheries SC Fisheries GA 131UJ UT WOS:000076593400004 ER PT J AU Velloso, AL Wasser, SK Monfort, SL Dietz, JM AF Velloso, AL Wasser, SK Monfort, SL Dietz, JM TI Longitudinal fecal steroid excretion in maned wolves (Chrysocyon brachyurus) SO GENERAL AND COMPARATIVE ENDOCRINOLOGY LA English DT Article DE fecal steroids; progestins; estradiol; testosterone; hormones; maned wolves ID PAPIO-CYNOCEPHALUS-CYNOCEPHALUS; ESTROUS-CYCLE; PROGESTERONE; PREGNANCY; SERUM; DOG; HORMONE; ESTRUS; BITCH; LH AB This study used a fecal steroid monitoring technique to evaluate reproductive cycles in male (4) and female (15) maned wolves, endangered South American canids. A radiolabeled testosterone infusion on a male revealed a fast and predominantly fecal route of excretion for this steroid. Testosterone was also excreted as eight unidentified metabolites, which was not the primary form of this steroid quantified in our assays. Fecal steroid concentrations (estradiol, E-2; progestins, P; testosterone, T) in males and acyclic, nonpregnant (pseudo-pregnant), and pregnant females were monitored over four breeding seasons (October-January). Significant differences were detected between longitudinal P profiles of cyclic and acyclic females during estrus, luteal phase, and after birth/end of pseudo-pregnancy Concentrations of P were also significantly higher in pregnant, compared to nonpregnant females, from proestrus to the end of the pregnant luteal phase. Although levels of T were higher in males than in females throughout the breeding season, no cyclicity in male fecal T concentrations was detected. Values of fecal P, T, and the ratio P/T were useful for differentiating gender and detecting pregnancy in females. Similarities to available data on other canids and the management and conservation implications of these findings were discussed, (C) 1998 Academic Press. C1 Univ Maryland, College Pk, MD 20742 USA. Univ Washington, Sch Med, Seattle, WA 98195 USA. Ctr Wildlife Conservat, Seattle, WA USA. Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Velloso, AL (reprint author), Rua Raimundo Magalhaes 86, BR-22451150 Rio De Janeiro, Brazil. NR 36 TC 42 Z9 47 U1 0 U2 10 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0016-6480 J9 GEN COMP ENDOCR JI Gen. Comp. Endocrinol. PD OCT PY 1998 VL 112 IS 1 BP 96 EP 107 DI 10.1006/gcen.1998.7147 PG 12 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 125WU UT WOS:000076260700012 PM 9748408 ER PT J AU Alroy, J AF Alroy, J TI Diachrony of mammalian appearance events: Implications for biochronology: Reply SO GEOLOGY LA English DT Article C1 Smithsonian Inst, Dept Paleobiol, Washington, DC 20560 USA. RP Alroy, J (reprint author), Smithsonian Inst, Dept Paleobiol, MRC 121, Washington, DC 20560 USA. RI Alroy, John/B-4585-2009 NR 5 TC 2 Z9 2 U1 0 U2 0 PU ASSOC ENGINEERING GEOLOGISTS GEOLOGICAL SOCIETY AMER PI COLLEGE STN PA TEXAS A & M UNIV, DEPT GEOLOGY & GEOPHYSICS, COLLEGE STN, TX 77843-3115 USA SN 0091-7613 J9 GEOLOGY JI Geology PD OCT PY 1998 VL 26 IS 10 BP 956 EP 958 PG 3 WC Geology SC Geology GA 125AG UT WOS:000076214800025 ER PT J AU Brown, WR Luu, JX AF Brown, WR Luu, JX TI Properties of model comae around Kuiper Belt and Centaur objects SO ICARUS LA English DT Article DE comets; Kuiper Belt objects; Centaurs ID 2060 CHIRON; COMETARY ACTIVITY; PARTICLE ORBITS; CCD PHOTOMETRY; INNER COMA; 2060-CHIRON; DUST; TEMPERATURE; EVOLUTION AB The cometary activity of Chiron inspires us to investigate observable lifetimes of hypothetical dust particles around large, distant Centaur and Kuiper Belt objects (KBOs). Our model computes dust particle trajectories assuming comet nucleus gravity, solar gravity, and solar radiation pressure. We find that particle lifetimes are extremely sensitive to the magnitude of the initial velocity. Long-lived orbits require an exact combination of nucleus size, heliocentric distance, particle size, and initial velocity. Estimating ejection velocities due to CO sublimation, we find that particles escape >50,000 km from Centaurs in 6 days and from KBOs in less than or similar to 10 days. Assuming optimal ejection velocities < nu(escape) upper limits to bound coma lifetimes are 50-75 days for Centaurs with Chiron-like activity. Thus Chiron's long-lived coma cannot be a result of an outburst. To observe a KBO coma requires a massive similar to 5 x 10(9)-kg dust coma, and its lifetime varies from <2 months to similar to 1 year depending on object size and heliocentric distance. (C) 1998 Academic Press. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Brown, WR (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 39 TC 7 Z9 7 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 OCT PY 1998 VL 135 IS 2 BP 415 EP 430 DI 10.1006/icar.1998.5964 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 138UD UT WOS:000076990700004 ER PT J AU Kidwell, PA AF Kidwell, PA TI Stalking the elusive computer bug SO IEEE ANNALS OF THE HISTORY OF COMPUTING LA English DT Article AB From at least the time of Thomas Edison, US. engineers have used the word "bug" to refer to flaws in the systems they developed. This short word conveniently covered a multitude of possible problems. It also suggested that difficulties were small and could be easily corrected. IBM engineers who installed the ASSC Mark I at Harvard University in 1944 taught the phrase to the staff there. Grace Murray Hopper used the word with particular enthusiasm in documents relating to her work. In 1947, when technicians building the Mark II computer at Harvard discovered a moth in one of the relays, they saved it as the first actual case of a bug being found. In the early 1950s, the terms "bug" and "debug," as applied to computers and computer programs, began to appear not only in computer documentation but even in the popular press. C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Kidwell, PA (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Rm 5128,MRC636, Washington, DC 20560 USA. NR 30 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1058-6180 J9 IEEE ANN HIST COMPUT JI IEEE Ann. Hist. Comput. PD OCT-DEC PY 1998 VL 20 IS 4 BP 5 EP 9 DI 10.1109/85.728224 PG 5 WC Computer Science, Theory & Methods; History & Philosophy Of Science SC Computer Science; History & Philosophy of Science GA 131BC UT WOS:000076555000002 ER PT J AU Leigh, EG AF Leigh, EG TI Religion and the order of nature SO INTERNATIONAL JOURNAL FOR PHILOSOPHY OF RELIGION LA English DT Book Review C1 Smithsonian Inst, Tropical Res Inst, Washington, DC 20560 USA. RP Leigh, EG (reprint author), Smithsonian Inst, Tropical Res Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0020-7047 J9 INT J PHILOS RELIG JI Int. J. Philos. Relig. PD OCT PY 1998 VL 44 IS 2 BP 124 EP 126 PG 3 WC Philosophy; Religion SC Philosophy; Religion GA 132VX UT WOS:000076652300006 ER PT J AU Wallington, TJ Jucks, KW Tyndall, GS AF Wallington, TJ Jucks, KW Tyndall, GS TI Upper limits for the gas-phase reaction of H2O2 with O-3 and NO. Atmospheric implications SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID HYDROGEN-PEROXIDE; WATER AB Upper limits of 4 x 10(-20) and 7 x 10(-20) cm(3) molecule(-1) s(-1) were established for the gas-phase reactions of H2O2 with O-3 and NO, respectively. These reactions are too slow to explain features observed in the atmospheric vertical profile of H2O2. (C) 1998 John Wiley C Sons. Inc. C1 Ford Motor Co, Sci Res Labs, Dearborn, MI 48121 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80303 USA. RP Wallington, TJ (reprint author), Ford Motor Co, Sci Res Labs, Mail Drop SRL-3083, Dearborn, MI 48121 USA. NR 7 TC 5 Z9 6 U1 4 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD OCT PY 1998 VL 30 IS 10 BP 707 EP 709 DI 10.1002/(SICI)1097-4601(1998)30:10<707::AID-KIN2>3.0.CO;2-Z PG 3 WC Chemistry, Physical SC Chemistry GA 124VJ UT WOS:000076203100002 ER PT J AU Gottlieb, CA McCarthy, MC Travers, MJ Grabow, JU Thaddeus, P AF Gottlieb, CA McCarthy, MC Travers, MJ Grabow, JU Thaddeus, P TI Rotational spectra of the carbon chain free radicals C10H, C12H, C13H, and C14H SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LABORATORY DETECTION; AB-INITIO; MOLECULES; MICROWAVE; SPECTROSCOPY; C7H AB The four carbon chain radicals C10H, C12H, C13H, and C14H have been observed in a pulsed supersonic molecular beam with a Fourier transform microwave spectrometer. The radicals were produced in a discharge through a dilute diacetylene/neon mixture in the throat of a supersonic nozzle. All are linear with (2)Pi electronic ground states, and all except C14H have resolved lambda-type doubling. For each species at least ten rotational transitions, between 6 and 16 GHz, were measured in the lowest spin component, which is (2)Pi(3/2) for C10H, C12H, and C14H, and (2)Pi(1/2) for C13H Only three spectroscopic constants in the standard Hamiltonian for a molecule in a (2)Pi state were required to reproduce the spectra to a few parts in 10(7): an effective rotational constant, a centrifugal distortion constant, and a lambda-type doubling constant. All of the chains here have abundances in the most intense part of the supersonic molecular beam of greater than or equal to 5 x 10(9) per gas pulse, which suggests that optical transitions of all four may be detectable with present laser techniques. For the carbon chain radicals with an even number of carbon atoms, there is very little change in relative abundance from C6H to C14H. (C) 1998 American Institute of Physics. [S0021-9606(98)00230-X]. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gottlieb, CA (reprint author), Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. OI McCarthy, Michael/0000-0001-9142-0008 NR 27 TC 35 Z9 35 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 1 PY 1998 VL 109 IS 13 BP 5433 EP 5438 DI 10.1063/1.477161 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 123YF UT WOS:000076152700031 ER PT J AU Balakrishnan, N Kharchenko, V Dalgarno, A AF Balakrishnan, N Kharchenko, V Dalgarno, A TI Slowing of energetic O(P-3) atoms in collisions with N-2 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID HOT OXYGEN GEOCORONA; NIGHTTIME TERRESTRIAL THERMOSPHERE; FAST NITROGEN-ATOMS; CROSS-SECTIONS; RATE CONSTANTS; KINETIC-MODEL; NITRIC-OXIDE; (3)A''; NO AB Energetic atoms influence the composition, the thermal structure and the evolution of the upper atmosphere. We investigate the slowing of energetic O(P-3) atoms by elastic and inelastic collisions with N-2. Results of quantum mechanical and semiclassical calculations of energy and angle-resolved cross sections are presented for elastic and inelastic collision of O(P-3) with N-2. A general analytical expression is developed for the kernel of the Boltzmann equation for the energy distribution function which is valid for elastic and inelastic collisions and incorporates both the angle and the energy dependence of the cross sections. The Boltzmann kernel for the energy relaxation of fast O(P-3) a,toms is evaluated using the computed cross sections. We report values of the collision frequency, the average energy loss in elastic and inelastic collisions with N-2, and the mean time and the number of collisions required to thermalize initially energetic O(P-3) atoms. We compare the efficiencies of elastic and inelastic collisions in slowing down fast O(P-3) atoms. These data are basic to the development of a reliable model of the atmospheric effects of the hot oxygen atoms produced by dissociative recombination, collisional quenching, photodissociation and photoelectron impact dissociation. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Balakrishnan, N (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. NR 27 TC 33 Z9 36 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD OCT 1 PY 1998 VL 103 IS A10 BP 23393 EP 23398 DI 10.1029/98JA02198 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 125XL UT WOS:000076262300006 ER PT J AU Fracalossi, DM Allen, ME Nichols, DK Oftedal, OT AF Fracalossi, DM Allen, ME Nichols, DK Oftedal, OT TI Oscars, Astronotus ocellatus, have a dietary requirement for vitamin C SO JOURNAL OF NUTRITION LA English DT Article; Proceedings Paper CT International Symposium on the Biology of Tropical Fishes at Aquaculture 98 CY FEB 15-19, 1998 CL LAS VEGAS, NEVADA DE ascorbic acid deficiency; L-gulonolactone oxidase; Astronotus ocellatus; ornamental fish ID CATFISH ICTALURUS-PUNCTATUS; TILAPIA OREOCHROMIS-NILOTICUS; JUVENILE RAINBOW-TROUT; ASCORBIC-ACID; CHANNEL CATFISH; DEFICIENCY; L-ASCORBYL-2-POLYPHOSPHATE; SULFATE; GROWTH; ASSAY AB We found that vitamin C is an essential nutrient for an Amazonian ornamental fish, the oscar (Astronotus ocellatus), This was demonstrated by the absence of L-gulonolactone oxidase activity, the enzyme responsible for the biosynthesis of vitamin C, in liver or kidney of oscars and by a feeding trial in which oscars without vitamin C dietary supplementation developed clinical deficiency signs. Fish weighing 29.2 +/- 1.9 g were divided into four groups, and each group was fed a casein-based semipurified diet containing 0, 25, 75 or 200 mg ascorbic acid equivalent (AA)/kg diet for 26 wk. Vitamin C was supplemented in the diets as L-ascorbyl-2-polyphosphate, a mixture of phosphate esters of ascorbate, which is more stable to oxidation than AA. At the end of 26 wk, fish fed no AA had significantly lower weight gain than fish fed the AA-supplemented diets (P < 0.05). Oscars without dietary AA supplementation gained only 37% of their initial weight, compared with 112, 102 and 91% gained by fish fed 25, 75 and 200 mg AA/kg diet, respectively. After 25 wk without dietary supplementation of AA, fish began to develop clinical deficiency signs, including deformed opercula and jaws, hemorrhage in the eyes and fins, and lordosis. Histology indicated that fish without AA supplementation had deformed gill filament support cartilage and atrophied muscle fibers. Collagen content of the vertebral column was significantly lower in fish devoid of dietary AA (P < 0.05). Liver AA concentration varied in proportion to dietary concentration of AA. The minimum dietary AA concentration tested in this study, 25 mg AA/kg diet, was sufficient to prevent growth reduction and AA deficiency signs in oscars. C1 Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. Smithsonian Inst, Natl Zool Pk, Dept Nutr Resources, Washington, DC 20008 USA. Smithsonian Inst, Natl Zool Pk, Dept Pathol, Washington, DC 20008 USA. RP Fracalossi, DM (reprint author), INPA, CPAQ, Alameda Cosme Ferreira, 1756 Manaus, BR-69083000 Manaus, Amazonas, Brazil. NR 41 TC 19 Z9 25 U1 0 U2 8 PU AMER INST NUTRITION PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-3166 J9 J NUTR JI J. Nutr. PD OCT PY 1998 VL 128 IS 10 BP 1745 EP 1751 PG 7 WC Nutrition & Dietetics SC Nutrition & Dietetics GA 124YQ UT WOS:000076210700025 PM 9772145 ER PT J AU Dickison, WC Weitzman, AL AF Dickison, WC Weitzman, AL TI Floral morphology and anatomy of Bonnetiaceae SO JOURNAL OF THE TORREY BOTANICAL SOCIETY LA English DT Article DE Dilleniidae; Bonnetiaceae; Clusiaceae; Theaceae; anatomy; flowers; systematics; Bonnetia ID GUAYANA AB A detailed study of floral morphology and anatomy of three genera comprising a narrowly circumscribed dicotyledonous family Bonnetiaceae is presented. Flowers are subtended by bracteoles and possess a perianth that is clearly differentiated into a 5-parted calyx and corolla composed of rather thick members. The androecium contains numerous stamens that are united at the base to form a short tube or collar or the stamens are pentadelphous and grouped at the base into five bundles that are positioned in the petal planes. Stamen fascicle traces are reported for the first time in flowers of Bonnetiaceae and are shown to originate close to, or adnate to, the median petal trace. Occasionally, two fascicle bundles arise side by side from a common gap as double bundles. Anther morphology and attachment is variable. Ploiarium possesses nectariferous discs that alternate with the stamen clusters. The presence of nectariferous tissue in Archytaea is variable. Nectaries can be supplied by double bundles, supporting the view that the nectaries of Plioarium and Archytaea represent transformed stamens. Gynoecia are compound, superior, and 3-carpellate or 5-carpellate. Styles range from divided to the base to undivided, and uniformly have a papillate stigma and a central canal filled with transfusion tissue. Placentation changes from axile to essentially parietal at midlevel of the ovary. Ovules are bitegmic, and contrasted with the putatively closely related Theaceae in which the elongated inner integument forms the micropyle, the outer integument projects well beyond the inner one. In addition to the degree of style fusion and carpel number, other important differences among genera of Bonnetiaceae are found in anther wall structure and floral vascular patterns. Major features of variation in the floral vascular system relate to the number and degree of independence of sepallary and petal traces; degree of independence of the androecial vascularization; the organization of the central ovarian vascular system; and the condition of the stylar vasculature. Comparisons are made among the flowers of Bonnetiaceae, Theaceae and Clusiaceae. C1 Univ N Carolina, Dept Biol, Chapel Hill, NC 27599 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RP Dickison, WC (reprint author), Univ N Carolina, Dept Biol, CB 3280, Chapel Hill, NC 27599 USA. NR 29 TC 12 Z9 15 U1 3 U2 4 PU TORREY BOTANICAL SOCIETY PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0040-9618 J9 J TORREY BOT SOC JI J. Torrey Bot. Soc. PD OCT-DEC PY 1998 VL 125 IS 4 BP 268 EP 286 DI 10.2307/2997241 PG 19 WC Plant Sciences SC Plant Sciences GA 146QZ UT WOS:000077443000003 ER PT J AU Dalling, JW Denslow, JS AF Dalling, JW Denslow, JS TI Soil seed bank composition along a forest chronosequence in seasonally moist tropical forest, Panama SO JOURNAL OF VEGETATION SCIENCE LA English DT Article DE Barro Colorado Nature Monument; forest regeneration; forest succession; germinable-seed bank; pioneer ID GAP-PHASE REGENERATION; RAIN-FOREST; FRENCH-GUYANA; PIONEER TREE; DYNAMICS; SUCCESSION; NEOTROPICS; VEGETATION AB We used a forest chronosequence at the Barro Colorado Nature Monument (BCNM) to examine changes in the abundance and species composition of seeds in the soil during forest succession. At each of eight sites varying from 20 yr to 100 yr since abandonment, and at two old-growth (>500 yr) forest stands, we established two 160-m transects and sampled the surface 0 - 3 cm of soil in cores collected at each 5 m interval. Seed densities were estimated from the number of seedlings germinated from the soil over a six-week period. Contrary to expectation, neither the density of the soil seed bank, nor species richness or diversity were directly related to age since abandonment, but the density of the soil seed bank was correlated with the abundance of seed-bank-forming species in the standing vegetation. In marked contrast to published studies, herbaceous taxa were rare even in the youngest stands, and the common tree species, which accounted for most seeds in the soil, were present in all stands. The pioneer tree Miconia argentea (Melastomataceae) was the single most common species in the seed bank, accounting for 62% of seeds and present in 92% of soil samples. Rapid recovery of the vegetation of young regrowth stands on BCNM, when compared to sites elsewhere may be partly due to allochthonous seed rain from nearby mature forest stands and the lack of seed inputs of weeds and grasses from agricultural and pasture lands which may inhibit forest succession. C1 Smithsonian Trop Res Inst, Balboa, Panama. Louisiana State Univ, Dept Plant Biol, Baton Rouge, LA 70803 USA. RP Dalling, JW (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 43 TC 43 Z9 47 U1 3 U2 25 PU OPULUS PRESS UPPSALA AB PI UPPSALA PA BOX 25137, S 752 25 UPPSALA, SWEDEN SN 1100-9233 J9 J VEG SCI JI J. Veg. Sci. PD OCT PY 1998 VL 9 IS 5 BP 669 EP 678 DI 10.2307/3237285 PG 10 WC Plant Sciences; Ecology; Forestry SC Plant Sciences; Environmental Sciences & Ecology; Forestry GA 150RZ UT WOS:000077680200007 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI Ben Shahn: An artist's life. 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 OCT 1 PY 1998 VL 123 IS 16 BP 82 EP 82 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 124AD UT WOS:000076157400046 ER PT J AU Bowen, WD Boness, DJ Iverson, SJ AF Bowen, WD Boness, DJ Iverson, SJ TI Estimation of total body water in harbor seals: How useful is bioelectrical impedance analysis? SO MARINE MAMMAL SCIENCE LA English DT Article DE bioelectrical impedance; total body water; deuterium; harbor seal; Phoca vitulina ID ANTARCTIC FUR SEALS; NORTHERN ELEPHANT SEAL; FAT-FREE MASS; ARCTOCEPHALUS-GAZELLA; MIROUNGA-ANGUSTIROSTRIS; NUTRIENT DEPOSITION; HALICHOERUS-GRYPUS; ISOTOPE-DILUTION; ENERGY-TRANSFER; PHOCA-VITULINA AB We evaluated bioelectrical impedance analysis (BIA) as a means of rapidly and inexpensively estimating total body water (TBW) of harbor seals (Phoca vitulina). Deuterium oxide dilution was used to estimate TBW in 17 adult females and 16 of their pups between birth and late lactation. Isotope dilution was also used to determine TBW in 12 adult males early and 10 of these males late in the breeding season. At the same time, resistance (Rs) and reactance (Xc) measurements were taken using a tetrapolar, impedance plethysmograph (Model 101A, RJL Systems). Seals were sedated with diazepam prior to taking BIA measurements. Within-day duplicate Rs measurements on pups and adults, taken 2-240 min apart, differed by an average of 3.0% +/- 1.4% (n = 42, CV = 102%). Movement of the seal during BIA measurements caused variability in both Rs and Xc values. BIA measurements were generally poor predictors of TBW. Rs was significantly correlated with TBW in pups only (Rs = 0.93, P = 0.001, n = 11). Bioelectrical conductor volume (length2/Rs) was significantly correlated with TBW only in adult females (Rs = 0.63, P = 0.02, n = 14). We conclude that BIA is not a reliable method of estimating TBW in wild harbor seals. C1 Fisheries & Oceans Canada, Bedford Inst Oceanog, Marine Fish Div, Dartmouth, NS B2Y 4A2, Canada. Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. Dalhousie Univ, Dept Biol, Halifax, NS B3H 3J5, Canada. RP Bowen, WD (reprint author), Fisheries & Oceans Canada, Bedford Inst Oceanog, Marine Fish Div, POB 1006, Dartmouth, NS B2Y 4A2, Canada. RI Bowen, William/D-2758-2012 NR 31 TC 5 Z9 5 U1 0 U2 6 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD OCT PY 1998 VL 14 IS 4 BP 765 EP 777 DI 10.1111/j.1748-7692.1998.tb00761.x PG 13 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 128FL UT WOS:000076395000007 ER PT J AU Houser, JL AF Houser, JL TI The effect of rotation on the gravitational radiation and dynamical stability of stiff stellar cores SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE instabilities; hydrodynamics; stars : neutron; stars : rotation ID SMOOTHED PARTICLE HYDRODYNAMICS; NONAXISYMMETRIC INSTABILITY; VERSATILE METHOD; NEUTRON-STARS; POLYTROPES; PROTOSTARS; EQUATIONS; ANTENNA; STATE; SPH AB Three-dimensional numerical simulations of non-axisymmetric dynamical instabilities in rotating stars are presented. These instabilities may operate during the collapse phase of rapidly rotating pre-supernova cores or in neutron stars spun up by accretion. Using a smoothed particle hydrodynamics (SPH) code, the effect of varying the rotation rate on the gravitational wave quantities, growth rate, and pattern speed of the instabilities is investigated. The star is modelled as a polytrope with index n = 0.5 and initially possesses T(rot)/\W\ = 0.26, 0.28, 0.30, 0.32, and 0.34. Here T(rot) is the rotational kinetic energy and \W\ is the gravitational potential energy of the entire system. The differentially rotating initial models are generated using a new rotational cooling method which properly allows odd-mode growth. This cooling technique is an important improvement over a previously used method that retained artificial grid symmetries and exhibited unrealistic odd-mode evolution. The code assumes a Newtonian gravitational field, and the gravitational radiation is calculated in the quadrupole approximation. This analysis shows that either a bar or a pear mode instability develops if the initial model possesses T(rot)/\W\ greater than or similar to 0.28. The instability sheds between 4-21 per cent and 14-62 per cent of the initial mass and angular momentum, respectively, in the form of a one- or two-armed spiral pattern. All initial models with T(rot)/\W\ greater than or equal to 0.28 become unstable to the growth of nonaxisymmetric instabilities and evolve toward an axisymmetric state surrounded by a flattened disc, The duration, amplitude, and frequency of the gravitational wave signals are sensitive to the initial value of T(rot)/\W\. Increases in this quantity result in a greater gravitational wave amplitude and frequency, but the duration of these signals is inversely proportional to increases in the initial stellar core rotation rate. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. MIT, Cambridge, MA 02139 USA. RP Houser, JL (reprint author), Smithsonian Astrophys Observ, Mail Stop 33, Cambridge, MA 02138 USA. EM jhouser@cfa.harvard.edu NR 42 TC 10 Z9 10 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 OCT 1 PY 1998 VL 299 IS 4 BP 1069 EP 1086 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 131AU UT WOS:000076554200017 ER PT J AU Prigozhin, GY Woo, J Gregory, JA Loomis, AH Bautz, MW Ricker, GR Kraft, S AF Prigozhin, GY Woo, J Gregory, JA Loomis, AH Bautz, MW Ricker, GR Kraft, S TI X-ray absorption near edge structure in the quantum efficiency of x-ray charge-coupled devices SO OPTICAL ENGINEERING LA English DT Article DE x-rays; charge-coupled devices; x-ray absorption fine structure ID AXAF AB We perform precise measurements of the x-ray transmission of the thin films comprising CCD gate structure, namely, phosphorus doped polysilicon, silicon dioxide, and silicon nitride. The x-ray transmission of these films shows large oscillations with small changes in energy in the vicinity of the following absorption edges: nitrogen K (400 eV), oxygen K (536 eV), silicon L and K (100 and 1840 eV, respectively). As a result, quantum efficiency of a CCD in the soft x-ray range deviates significantly from simple model predictions based on Henke et at. (1993) mass absorption coefficients. The measurements covered the range of energies from 60 to 3000 eV, using synchrotron beamlines at the Advanced Light Source (ALS; Berkeley), Physikalisch-Technische Bundesanstalt BESSY (Berlin), the Synchrotron Radiation Center (SRC; University of Wisconsin-Madison). Our model of the CCD response includes near edge x-ray absorption structure and predicts a very complicated shape of the energy dependence of the quantum efficiency around silicon and oxygen absorption edges. Experimental measurements of CCD quantum efficiency relative to a calibrated detector at the BESSY synchrotron confirmed our model predictions for both frontside and backside illuminated CCDs. (C) 1998 Society of Photo-Optical instrumentation Engineers. [S0091-3286(98)01910-2]. C1 MIT, Ctr Space Res, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02139 USA. MIT, Lincoln Lab, Lexington, MA 02173 USA. Phys Tech Bundesanstalt, BESSY GMBH, D-14195 Berlin, Germany. RP MIT, Ctr Space Res, 77 Massachusetts Ave, Cambridge, MA 02139 USA. EM gyp@space.mit.edu NR 7 TC 18 Z9 18 U1 0 U2 0 PU SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 0091-3286 EI 1560-2303 J9 OPT ENG JI Opt. Eng. PD OCT PY 1998 VL 37 IS 10 BP 2848 EP 2854 DI 10.1117/1.601823 PG 7 WC Optics SC Optics GA 128GY UT WOS:000076398600026 ER PT J AU Kaplan, L Heller, EJ AF Kaplan, L Heller, EJ TI Weak quantum ergodicity SO PHYSICA D-NONLINEAR PHENOMENA LA English DT Article ID EIGENFUNCTIONS; SYSTEMS AB We examine the consequences of classical ergodicity for the localization properties of individual quantum eigenstates in the classical limit. We note that the well-known Schnirelman result is a weaker form of quantum ergodicity than the one implied by random matrix theory. This suggests the possibility of systems with non-gaussian random eigenstates which are nonetheless ergodic in the sense of Schnirelman and lead to ergodic transport in the classical limit. These we call "weakly quantum ergodic". Indeed for a class of "slow ergodic" classical systems, it is found that each eigenstate becomes localized to an ever decreasing fraction of the available state space, in the semiclassical limit. Nevertheless, each eigenstate in this limit covers phase space evenly on any classical scale, and long-time transport properties between individual quantum states remain ergodic due to the diffractive effects which dominate quantum phase space exploration. (C) 1998 Elsevier Science B.V. C1 Harvard Univ, Dept Phys, Cambridge, MA 02138 USA. Harvard Univ, Soc Fellows, Cambridge, MA 02138 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Univ, Dept Phys, Cambridge, MA 02138 USA. EM kaplan@huhepl.harvard.edu; heller@physics.harvard.edu NR 23 TC 33 Z9 33 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 EI 1872-8022 J9 PHYSICA D JI Physica D PD OCT 1 PY 1998 VL 121 IS 1-2 BP 1 EP 18 DI 10.1016/S0167-2789(98)00156-0 PG 18 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA 119BZ UT WOS:000075876600001 ER PT J AU Meyer, GM Briegel, HJ AF Meyer, GM Briegel, HJ TI Pump-operator treatment of the ion-trap laser SO PHYSICAL REVIEW A LA English DT Article ID OPTICAL MASTER-EQUATIONS; DRIVEN 3-LEVEL ATOMS; QUANTUM; INVERSION; COHERENCE; EMISSION; LIGHT AB We present a detailed treatment of a laser process that has been predicted for an experiment with a single trapped Ca+ ion. It is demonstrated how the complex multilevel system can be understood as a coherently pumped three-level scheme with time-delayed pumping out of the metastable lower laser level. This is described by a pump operator, which simplifies the numerical analysis substantially and allows for a treatment of more complicated systems. [S1050-2947(98)08809-X]. C1 Max Planck Inst Quantum Opt, D-85748 Garching, Germany. Univ Innsbruck, Inst Theoret Phys, A-6270 Innsbruck, Austria. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Max Planck Inst Quantum Opt, Hans Kopfermann Str 1, D-85748 Garching, Germany. NR 21 TC 13 Z9 14 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1998 VL 58 IS 4 BP 3210 EP 3220 DI 10.1103/PhysRevA.58.3210 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 127WQ UT WOS:000076373900077 ER PT J AU Forrey, RC Balakrishnan, N Kharchenko, V Dalgarno, A AF Forrey, RC Balakrishnan, N Kharchenko, V Dalgarno, A TI Feshbach resonances in ultracold atom-diatom scattering SO PHYSICAL REVIEW A LA English DT Article ID MOLECULES AB Quantum-mechanical scattering calculations of Feshbach resonances arising from van der Waals molecule formation are used to determine vibrational and rotational predissociation lifetimes. A multichannel effective range theory is used to establish the relationship between predissociation and the zero-temperature limit of collisional quenching for resonances lying close to the thresholds for dissociation. The elastic scattering Feshbach resonances may be measurable in ultracold atom-molecule experiments. [S1050-2947(98)51510-7]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Forrey, RC (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. NR 18 TC 52 Z9 53 U1 0 U2 1 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 OCT PY 1998 VL 58 IS 4 BP R2645 EP R2647 DI 10.1103/PhysRevA.58.R2645 PG 3 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 127WQ UT WOS:000076373900007 ER PT J AU Foster, GA Mathis, WN AF Foster, GA Mathis, WN TI A revision of the family Tethinidae (Diptera) from the Caribbean, Gulf of Mexico, and Bermuda SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE revision; Diptera; Tethinidae; Dasyrhicnoessa; Pelomyiella; Tethina; Caribbean; Gulf of Mexico; Bermuda AB Beach flies (Diptera: Tethinidae) of the Caribbean, Gulf of Mexico, and Bermuda are revised. The beach-fly fauna of this area comprises three genera (Dasyrhicnoessa, Pelomyiella, and Tethina) and 12 species, including the following new species (type locality in parenthesis): Tethina albitarsa (ECUADOR. Manabi: Bahia), T. cohiba (GRAND CAYMAN. George Town Harbour (19 degrees 18'N, 81 degrees 22.9'W)), T. lisae (JAMAICA. Clarendon: Jackson Bay (17 degrees 44.7'N, 77 degrees 12.6'W)). Five new synonyms are proposed (junior synonyms cited first): Tethina chilensis Malloch = Rhicnoessa texana Malloch, Tethina carioca Prado and Tavares and Rhicnoessa variseta Melander = Rhicnoessa willistoni Melander, Tethina brasiliensis Prado and Tavares and Rhicnoessa seriata Melander Tethina xanthopoda Williston. Dasyrhicnoessa lasiophthalma was probably introduced into the region. The remaining species tend to be widespread and frequently are locally abundant. These factors have contributed in part to some species being described multiple times. C1 Smithsonian Inst, Museum Natl Hist Nat, Dept Entomol, Washington, DC 20560 USA. RP Foster, GA (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Entomol, MRC 169, Washington, DC 20560 USA. EM mathis.wayne@nmnh.si.edu NR 46 TC 7 Z9 9 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 OCT PY 1998 VL 100 IS 4 BP 601 EP 632 PG 32 WC Entomology SC Entomology GA 132AH UT WOS:000076607100001 ER PT J AU Adamski, D AF Adamski, D TI On the identity of Holcocera guilandinae (Busck 1900) (Lepidoptera : Gelechioidea : Coleophoridae : Blastobasinae) SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Holcocera; Holcocerini; crassicornella; grenadensis; guilandinae AB Adults of Holcocera guilandinae (Busck 1900) can be confused with two other species, H. crassicornella Dietz 1910, and H. grenadensis (Walsingham 1897). A lectotype is designated for Blastobasis grenadensis, and this species is transferred from Blastobasis Zeller 1855 to Holcocera Clemens 1863 (n. comb.). All three Holcocera species are redescribed herein, with complete synonymies given. Photographs of images, illustrations of the male and female genitalia and wing venation, and a key to the species are provided. C1 Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Adamski, D (reprint author), Smithsonian Inst, Dept Entomol, NHB-127, Washington, DC 20560 USA. NR 20 TC 1 Z9 1 U1 0 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 OCT PY 1998 VL 100 IS 4 BP 731 EP 741 PG 11 WC Entomology SC Entomology GA 132AH UT WOS:000076607100013 ER PT J AU Huang, YH Rueda, LM AF Huang, YH Rueda, LM TI Description of a paralectotype female of Aedes (Finlaya) Niveus (Ludlow) (Diptera : Culicidae) SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE description; paralectotype; Culicidae; mosquitoes; Aedes niveus; vector; filaria; Philippines AB A paralectotype female of Aedes (Finlaya) niveus (Ludlow) from Oras, Samar, Philippine Islands is described and illustrated. C1 Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Huang, YH (reprint author), Smithsonian Inst, Dept Entomol, MRC 534, Washington, DC 20560 USA. NR 10 TC 1 Z9 1 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 OCT PY 1998 VL 100 IS 4 BP 824 EP 827 PG 4 WC Entomology SC Entomology GA 132AH UT WOS:000076607100020 ER PT J AU Krombein, KV AF Krombein, KV TI Brachystegus decoratus (Turner) (Hymenoptera : Sphecidae), an Indian wasp new to Sri Lanka SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article C1 Smithsonian Inst, Museum Natl Hist Nat, Dept Entomol, Washington, DC 20560 USA. RP Krombein, KV (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Entomol, MRC 165, Washington, DC 20560 USA. NR 0 TC 0 Z9 1 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 OCT PY 1998 VL 100 IS 4 BP 828 EP 828 PG 1 WC Entomology SC Entomology GA 132AH UT WOS:000076607100021 ER PT J AU Froeschner, RC AF Froeschner, RC TI Obituary - Nicholas A. Kormilev - 1901-1998 SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Biographical-Item C1 Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Froeschner, RC (reprint author), Smithsonian Inst, Dept Entomol, MRC-105, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 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 OCT PY 1998 VL 100 IS 4 BP 838 EP 838 PG 1 WC Entomology SC Entomology GA 132AH UT WOS:000076607100023 ER PT J AU Pahre, MA AF Pahre, MA TI Elliptical galaxies: Structure, stellar content, and evolution SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article C1 CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. RP Pahre, MA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 20, 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 SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD OCT PY 1998 VL 110 IS 752 BP 1249 EP 1249 DI 10.1086/316238 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 134LU UT WOS:000076745200011 ER PT J AU Stine, JK Tarr, JA AF Stine, JK Tarr, JA TI At the intersection of histories - Technology and the environment SO TECHNOLOGY AND CULTURE LA English DT Review ID UNITED-STATES; URBAN; GEOGRAPHY; POLLUTION; ECOLOGY; WASTES C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RP Stine, JK (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RI STEWART, J/G-4491-2011 NR 417 TC 51 Z9 51 U1 1 U2 4 PU JOHNS HOPKINS UNIV PRESS PI BALTIMORE PA JOURNALS PUBLISHING DIVISION, 2715 NORTH CHARLES ST, BALTIMORE, MD 21218-4319 USA SN 0040-165X J9 TECHNOL CULT JI Technol. Cult. PD OCT PY 1998 VL 39 IS 4 BP 601 EP 640 DI 10.2307/1215842 PG 40 WC History & Philosophy Of Science SC History & Philosophy of Science GA 135LR UT WOS:000076803600002 ER PT J AU Stine, JK AF Stine, JK TI The politics of expertise in congress: The rise and fall of the office of technology assessment. SO TECHNOLOGY AND CULTURE LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Stine, JK (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU JOHNS HOPKINS UNIV PRESS PI BALTIMORE PA JOURNALS PUBLISHING DIVISION, 2715 NORTH CHARLES ST, BALTIMORE, MD 21218-4319 USA SN 0040-165X J9 TECHNOL CULT JI Technol. Cult. PD OCT PY 1998 VL 39 IS 4 BP 815 EP 816 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA 135LR UT WOS:000076803600046 ER PT J AU Neal, V AF Neal, V TI The challenger launch decision: Risky technology, culture, and deviance at NASA. SO TECHNOLOGY AND CULTURE LA English DT Book Review C1 Smithsonian Inst, Natl Air & Space Museum, Dept Space Hist, Washington, DC 20560 USA. RP Neal, V (reprint author), Smithsonian Inst, Natl Air & Space Museum, Dept Space Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 1 U2 1 PU JOHNS HOPKINS UNIV PRESS PI BALTIMORE PA JOURNALS PUBLISHING DIVISION, 2715 NORTH CHARLES ST, BALTIMORE, MD 21218-4319 USA SN 0040-165X J9 TECHNOL CULT JI Technol. Cult. PD OCT PY 1998 VL 39 IS 4 BP 816 EP 818 PG 3 WC History & Philosophy Of Science SC History & Philosophy of Science GA 135LR UT WOS:000076803600047 ER EF