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81.
82.
Young DT Berthelier JJ Blanc M Burch JL Bolton S Coates AJ Crary FJ Goldstein R Grande M Hill TW Johnson RE Baragiola RA Kelha V McComas DJ Mursula K Sittler EC Svenes KR Szegö K Tanskanen P Thomsen MF Bakshi S Barraclough BL Bebesi Z Delapp D Dunlop MW Gosling JT Furman JD Gilbert LK Glenn D Holmlund C Illiano JM Lewis GR Linder DR Maurice S McAndrews HJ Narheim BT Pallier E Reisenfeld D Rymer AM Smith HT Tokar RL Vilppola J Zinsmeyer C 《Science (New York, N.Y.)》2005,307(5713):1262-1266
During Cassini's initial orbit, we observed a dynamic magnetosphere composed primarily of a complex mixture of water-derived atomic and molecular ions. We have identified four distinct regions characterized by differences in both bulk plasma properties and ion composition. Protons are the dominant species outside about 9 RS (where RS is the radial distance from the center of Saturn), whereas inside, the plasma consists primarily of a corotating comet-like mix of water-derived ions with approximately 3% N+. Over the A and B rings, we found an ionosphere in which O2+ and O+ are dominant, which suggests the possible existence of a layer of O2 gas similar to the atmospheres of Europa and Ganymede. 相似文献
83.
Zeng R Farias FH Johnson GS McKay SD Schnabel RD Decker JE Taylor JF Mann CS Katz ML Johnson GC Coates JR O'Brien DP 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2011,25(2):267-272
Background: Bandera's neonatal ataxia (BNAt) is an autosomal recessive cerebellar ataxia that affects members of the Coton de Tulear dog breed. Objective: To identify the mutation that causes BNAt. Animals: The study involved DNA from 112 Cotons de Tulear (including 15 puppies with signs of BNAt) and 87 DNA samples from dogs of 12 other breeds. Methods: The BNAt locus was mapped with a genome‐wide association study (GWAS). The coding exons of positional candidate gene GRM1, which encodes metabotropic glutamate receptor 1, were polymerase chain reaction (PCR)‐amplified and resequenced. A 3‐primer PCR assay was used to genotype individual dogs for a truncated retrotransposon inserted into exon 8 of GRM1. Results: The GWAS indicated that the BNAt locus was in a canine chromosome 1 region that contained candidate gene GRM1. Resequencing this gene from BNAt‐affected puppies indicated that exon 8 was interrupted by the insertion of a 5′‐truncated retrotransposon. All 15 BNAt‐affected puppies were homozygous for the insert, whereas all other Cotons de Tulear were heterozygotes (n = 43) or homozygous (n = 54) for the ancestral allele. None of the 87 dogs from 12 other breeds had the insertion allele. Conclusions and Clinical Importance: BNAt is caused by a retrotransposon inserted into exon 8 of GRM1. A DNA test for the GRM1 retrotransposon insert can be used for genetic counseling and to confirm the diagnosis of BNAt. 相似文献
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Lundin R Barabash S Andersson H Holmström M Grigoriev A Yamauchi M Sauvaud JA Fedorov A Budnik E Thocaven JJ Winningham D Frahm R Scherrer J Sharber J Asamura K Hayakawa H Coates A Linder DR Curtis C Hsieh KC Sandel BR Grande M Carter M Reading DH Koskinen H Kallio E Riihela P Schmidt W Säles T Kozyra J Krupp N Woch J Luhmann J McKenna-Lawler S Cerulli-Irelli R Orsini S Maggi M Mura A Milillo A Roelof E Williams D Livi S Brandt P Wurz P Bochsler P 《Science (New York, N.Y.)》2004,305(5692):1933-1936
The Analyzer of Space Plasma and Energetic Atoms (ASPERA) on board the Mars Express spacecraft found that solar wind plasma and accelerated ionospheric ions may be observed all the way down to the Mars Express pericenter of 270 kilometers above the dayside planetary surface. This is very deep in the ionosphere, implying direct exposure of the martian topside atmosphere to solar wind plasma forcing. The low-altitude penetration of solar wind plasma and the energization of ionospheric plasma may be due to solar wind irregularities or perturbations, to magnetic anomalies at Mars, or both. 相似文献
86.
Bertucci C Achilleos N Dougherty MK Modolo R Coates AJ Szego K Masters A Ma Y Neubauer FM Garnier P Wahlund JE Young DT 《Science (New York, N.Y.)》2008,321(5895):1475-1478
After 3 years and 31 close flybys of Titan by the Cassini Orbiter, Titan was finally observed in the shocked solar wind, outside of Saturn's magnetosphere. These observations revealed that Titan's flow-induced magnetosphere was populated by "fossil" fields originating from Saturn, to which the satellite was exposed before its excursion through the magnetopause. In addition, strong magnetic shear observed at the edge of Titan's induced magnetosphere suggests that reconnection may have been involved in the replacement of the fossil fields by the interplanetary magnetic field. 相似文献
87.
Coates AJ 《Science (New York, N.Y.)》2011,332(6034):1157-1158
88.
Kim JY Lee K Coates NE Moses D Nguyen TQ Dante M Heeger AJ 《Science (New York, N.Y.)》2007,317(5835):222-225
Tandem solar cells, in which two solar cells with different absorption characteristics are linked to use a wider range of the solar spectrum, were fabricated with each layer processed from solution with the use of bulk heterojunction materials comprising semiconducting polymers and fullerene derivatives. A transparent titanium oxide (TiO(x)) layer separates and connects the front cell and the back cell. The TiO(x) layer serves as an electron transport and collecting layer for the first cell and as a stable foundation that enables the fabrication of the second cell to complete the tandem cell architecture. We use an inverted structure with the low band-gap polymer-fullerene composite as the charge-separating layer in the front cell and the high band-gap polymer composite as that in the back cell. Power-conversion efficiencies of more than 6% were achieved at illuminations of 200 milliwatts per square centimeter. 相似文献
89.
Waite JH Young DT Cravens TE Coates AJ Crary FJ Magee B Westlake J 《Science (New York, N.Y.)》2007,316(5826):870-875
Titan's lower atmosphere has long been known to harbor organic aerosols (tholins) presumed to have been formed from simple molecules, such as methane and nitrogen (CH4 and N2). Up to now, it has been assumed that tholins were formed at altitudes of several hundred kilometers by processes as yet unobserved. Using measurements from a combination of mass/charge and energy/charge spectrometers on the Cassini spacecraft, we have obtained evidence for tholin formation at high altitudes (approximately 1000 kilometers) in Titan's atmosphere. The observed chemical mix strongly implies a series of chemical reactions and physical processes that lead from simple molecules (CH4 and N2) to larger, more complex molecules (80 to 350 daltons) to negatively charged massive molecules (approximately 8000 daltons), which we identify as tholins. That the process involves massive negatively charged molecules and aerosols is completely unexpected. 相似文献
90.