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81.
82.
Ross IM 《Science (New York, N.Y.)》1982,217(4555):130-131
The promise of technology for improving the quality of life has never been greater, and American science and technology has led the way toward fulfillment of that promise. Now this preeminence is threatened by forces that may affect technological progress throughout the world. It is up to those of us in science, industry, and government to strengthen the institutions that have made us the leaders and to restore our initiative. 相似文献
83.
Reoviruslike agent in stools: association with infantile diarrhea and development of serologic tests 总被引:39,自引:0,他引:39
A Z Kapikian H W Kim R G Wyatt W J Rodriguez S Ross W L Cline R H Parrott R M Chanock 《Science (New York, N.Y.)》1974,185(156):1049-1053
Reoviruslike particles were visualized by electron microscopy in stool filtrates prepared from stools of infants and young children with severe acute gastroenteritis. Patients who had such particles in their stools and whose paired acute and convalescent serums were tested developed an antibody response to the reoviruslike agent, which was measured by immune electron microscopy and by complement fixation. The reoviruslike agent was antigenically related to the epizootic diarrhea of infant mice virus and the Nebraska calf diarrhea virus. 相似文献
84.
The Law of the Sea treaty will clearly affect the way U.S. marine scientists operate in about 40 percent of the ocean. The matter will be made even more complex by the apparent intention of the Reagan Administration to remain outside the treaty. 相似文献
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87.
Real-time observations were made of the shape change from pyramids to domes during the growth of germanium-silicon islands on silicon (001). Small islands are pyramidal in shape, whereas larger islands are dome-shaped. During growth, the transition from pyramids to domes occurs through a series of asymmetric transition states with increasing numbers of highly inclined facets. Postgrowth annealing of pyramids results in a similar shape change process. The transition shapes are temperature dependent and transform reversibly to the final dome shape during cooling. These results are consistent with an anomalous coarsening model for island growth. 相似文献
88.
Everyday observation reveals that both individuals and organizations often become overly committed to losing courses of action; in a sense, throwing good money after bad. More than 10 years of research on this escalation problem shows that persistence is associated with at least four major clases of determinants: project, psychological, social, and organizational variables. The influence of these four sets of variables evolves over time, forming a dynamic model of behavior in escalation situations. 相似文献
89.
Ross M 《Science (New York, N.Y.)》1989,244(4902):311-317
Largely in response to the energy shocks of the 1970s, U.S. manufacturers reduced their real fossil fuel intensity (the weighted-average ratio of energy use to production in each subsector) by 50% and achieved zero growth in real electricity intensity. In the future, adoption of new technologies for increasing the efficiency of electricity use is likely to continue to be as important as new modes of electrification, implying that the real electricity intensity will be stable; but the outcome depends on electricity pricing and other policies, public and private. 相似文献
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