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101.
Pool R 《Science (New York, N.Y.)》1989,243(4899):1661-1662
102.
Roizen R 《Science (New York, N.Y.)》1996,274(5292):1450b-1451b
103.
Buddemeier RW 《Science (New York, N.Y.)》1996,271(5253):1298a-1299b
104.
Kerr RA 《Science (New York, N.Y.)》1994,263(5147):625-626
105.
Jayawardhana R 《Science (New York, N.Y.)》1994,265(5178):1526-1527
The Hague, Netherlands, last month welcomed 2000 astronomers from around the world for the 22nd General Assembly of the International Astronomical Union (IAU). From 15 to 27 August, they participated in symposia and discussions on topics ranging from the down-to-Earth issue of light and radio-frequency pollution to the creation of elements at the farthest reaches of time and space, in the big bang. Some of the most striking news, however, came in new findings from our galaxy and its immediate surroundings. 相似文献
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Much attention is focused today on predicting how plants will respond to anticipated changes in atmospheric composition and climate, and in particular to increases in CO(2) concentration. Here we review the long-term global fluctuations in atmospheric CO(2) concentration as a framework for understanding how current trends in atmospheric CO(2) concentration fit into a selective, evolutionary context. We then focus on an integrated approach for understanding how gas exchange metabolism responds to current environmental conditions, how it previously responded to glacial-interglacial conditions, and how it may respond to future changes in atmospheric CO(2) concentration. 相似文献
110.
Opel JR 《Science (New York, N.Y.)》1984,225(4660):378-380
The open society, unlike the closed society, requires constant citizen thought and action to ensure that it will continue to survive and prosper. Today in the United States we should give particular attention to three immediate problems. We should reinvigorate our national economic health and international competitiveness, particularly by reducing our unprecedented budget deficits and reforming our tax system. We must strengthen our scientific and engineering vitality, particularly in graduate engineering education and in secondary school instruction in science and mathematics. And we should work with our allies in the free industrialized world to keep our international open society as open as possible, encouraging a flow of people and information and ideas across national boundaries while instituting sensible and efficient safeguards against leakage of critical military technology to the Soviet Union. 相似文献