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91.
Trombka JI Squyres SW Bruckner J Boynton WV Reedy RC McCoy TJ Gorenstein P Evans LG Arnold JR Starr RD Nittler LR Murphy ME Mikheeva I McNutt RL McClanahan TP McCartney E Goldsten JO Gold RE Floyd SR Clark PE Burbine TH Bhangoo JS Bailey SH Petaev M 《Science (New York, N.Y.)》2000,289(5487):2101-2105
We report major element composition ratios for regions of the asteroid 433 Eros imaged during two solar flares and quiet sun conditions during the period of May to July 2000. Low aluminum abundances for all regions argue against global differentiation of Eros. Magnesium/silicon, aluminum/silicon, calcium/silicon, and iron/silicon ratios are best interpreted as a relatively primitive, chondritic composition. Marked depletions in sulfur and possible aluminum and calcium depletions, relative to ordinary chondrites, may represent signatures of limited partial melting or impact volatilization. 相似文献
92.
Evans JW 《Science (New York, N.Y.)》1972,176(4033):416-417
Sets of growth lines in the shell of Clinocardium nuttalli are extinguished every 13 or 14 increments only to be replaced by other sets, half an increment out of phase with the first. This can be explained only by assuming that the lines are deposited during periods of exposure at low tide. The average duration of an increment is 24 hours and 50 minutes. 相似文献
93.
Evans FC 《Science (New York, N.Y.)》1956,123(3208):1127-1128
94.
Warwick JW Evans DR Romig JH Alexander JK Desch MD Kaiser ML Aubier M Leblanc Y Lecacheux A Pedersen BM 《Science (New York, N.Y.)》1982,215(4532):582-587
Planetary radio astronomy measurements obtained by Voyager 2 near Saturn have added further evidence that Saturnian kilometric radiation is emitted by a strong dayside source at auroral latitudes in the northern hemisphere and by a weaker source at complementary latitudes in the southern hemisphere. These emissions are variable because of Saturn's rotation and, on longer time scales, probably because of influences of the solar wind and Dione. The electrostatic discharge bursts first discovered by Voyager 1 and attributed to emissions from the B ring were again observed with the same broadband spectral properties and an episodic recurrence period of about 10 hours, but their occurrence frequency was only about 30 percent of that detected by Voyager 1. While crossing the ring plane at a distance of 2.88 Saturn radii, the spacecraft detected an intense noise event extending to above 1 megahertz and lasting about 150 seconds. The event is interpreted to be a consequence of the impact, vaporization, and ionization of charged, micrometer-size G ring particles distributed over a vertical thickness of about 1500 kilometers. 相似文献
95.
Rendulic S Jagtap P Rosinus A Eppinger M Baar C Lanz C Keller H Lambert C Evans KJ Goesmann A Meyer F Sockett RE Schuster SC 《Science (New York, N.Y.)》2004,303(5658):689-692
Predatory bacteria remain molecularly enigmatic, despite their presence in many microbial communities. Here we report the complete genome of Bdellovibrio bacteriovorus HD100, a predatory Gram-negative bacterium that invades and consumes other Gram-negative bacteria. Its surprisingly large genome shows no evidence of recent gene transfer from its prey. A plethora of paralogous gene families coding for enzymes, such as hydrolases and transporters, are used throughout the life cycle of B. bacteriovorus for prey entry, prey killing, and the uptake of complex molecules. 相似文献
96.
Two different cis-active elements transfer the transcriptional effects of both EGF and phorbol esters 总被引:27,自引:0,他引:27
H P Elsholtz H J Mangalam E Potter V R Albert S Supowit R M Evans M G Rosenfeld 《Science (New York, N.Y.)》1986,234(4783):1552-1557
97.
98.
EA Adelberg 《Science (New York, N.Y.)》1964,146(3648):1193-1195
99.
The metal-binding protein metallothionein was isolated from the livers of Wilson's disease patients and control subjects. The metals were removed from the native protein to produce the apoprotein, and copperthionein was prepared by equilibrium dialysis. Copperthionein from Wilson's disease patients had a copper-binding constant four times as great as that of the protein from control subjects. These results suggest that the alterations in copper homeostasis in Wilson's disease result from the synthesis of an abnormal metal-binding protein with an increased affinity for copper. 相似文献
100.