Ancestors Worshiped: Paleoanthropologists have been discussing their agreements and disagreements in the presence of most of the world's hominid fossils     

Lewin R 《Science (New York, N.Y.)》1984,224(4648):477-479

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Recombinant RNA research     

Cedergren RJ 《Science (New York, N.Y.)》1984,226(4672):242

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An Encouraging Long-Term Quake "Forecast": The anticipation of the size and location of last April's Morgan Hill earthquake was two-thirds of a prediction; predicting a precise time remains out of reach     

Kerr RA 《Science (New York, N.Y.)》1984,225(4659):300-301

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Surprise finding with insect globin genes     

Lewin R 《Science (New York, N.Y.)》1984,226(4672):328

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Ductile ordered intermetallic alloys     

Liu CT  Stiegler JO 《Science (New York, N.Y.)》1984,226(4675):636-642

Many ordered intermetallic alloys have attractive high-temperature properties; however, low ductility and brittle fracture limit their use for structural applications. The embrittlement in these alloys is mainly caused by an insufficient number of slip systems (bulk brittleness) and poor grain-boundary cohesion. Recent studies have shown that the ductility and fabricability of ordered intermetallics can be substantially improved by alloying processes and control of microstructural features through rapid solidification and thermomechanical treatments. These results demonstrate that the brittleness problem associated with ordered intermetallics can be overcome by using physical metallurgical principles. Application of these principles will be illustrated by results on Ni(3)Al and Ni(3)V-Co(3)V-Fe(3)V. The potential for developing these alloys as a new class of high-temperature structural materials is discussed.  相似文献   

Antievolution Rules Are Unconstitutional: The Texas attorney general has said that the state's textbook antievolution rules violate the First Amendment; creationists will fight the opinion     

Lewin R 《Science (New York, N.Y.)》1984,223(4643):1373-1374

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A defect in the limited war theory     

Smith RJ 《Science (New York, N.Y.)》1984,223(4642):1271

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Shuttle flight scrubbed     

Smith RJ 《Science (New York, N.Y.)》1984,225(4660):395

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The open society     

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   

Holocene history of cedar and native Indian cultures of the north american pacific coast     

Hebda RJ  Mathewes RW 《Science (New York, N.Y.)》1984,225(4663):711-713

A comparison of paleobotanical records with archeological and ethnographic evidence from the Pacific Northwest shows a strong correlation between the expansion of Western red cedar (Thuja plicata) in coastal forests between 5000 and 2500 years ago and the evolution of a massive woodworking technology by native cultures. This suggests that an important component of cultural development was environmentally constrained until large cedar trees, the basic resource for canoe-building and plank-house construction, had become available in late Holocene time.  相似文献