Inquiry Faults Shuttle Management: Rogers Commission calls for sweeping reforms in NASA's operations, as well as substantial changes in the design of the solid-rocket seals     

Smith RJ 《Science (New York, N.Y.)》1986,232(4757):1488-1489

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Myths and Methods in Ice Age Art: The painted caves of Ice Age Europe have always entranced those who study them, but new directions in archeology are showing how some popular interpretations might have gone awry     

Lewin R 《Science (New York, N.Y.)》1986,234(4779):936-938

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Molecular transformations on single crystal metal surfaces     

Madix RJ 《Science (New York, N.Y.)》1986,233(4769):1159-1166

One of the primary objectives of modern surface chemistry of transition metals is the synthesis of surface compounds and complexes and the understanding of their reactivity, structure, and bonding. Such considerations are paramount for advancing understanding of catalysis, adhesion, organic thin-film growth, and electrocatalysis. On selected metals, particularly copper, silver, and gold, selective scission of X-H bonds (where X is oxygen, carbon, nitrogen, or sulfur) by surface-bound atomic oxygen occurs to form moderately stable species that can be isolated for further study. Selective oxidation reactions may occur heterogeneously by means of this novel oxygen- activated route. Furthermore, this selective chemistry offers a paradigm for synthesis of a wide variety of surface organometallic complexes, whose formation can be predicted from acid-base principles. These subjects are discussed in this article with emphasis on their role in catalytic oxidation cycles.  相似文献   

Blacks in science: black scientists, white society, and colorless science     

Marrett CB 《Science (New York, N.Y.)》1986,231(4737):505-506

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Administration of research     

Gross PR 《Science (New York, N.Y.)》1986,232(4754):1078

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Phalangeal and navicular bone hypoplasia and hoof malformation in the hind limbs of a foal          下载免费PDF全文

Smith DR  Leach DH  Bell RJ 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(1):28-30,31-34

Anatomical anomalies in the hind feet of a seven month old Appaloosa foal were identified and investigated through the use of gross anatomical dissection, radiography and angiography. Abnormalities were restricted to the distal aspect of both hind legs, the right hind leg being more severely affected. Anatomically the right foot resembled that of an equine fetus of approximately 120 days gestational age. Disruption of vascular perfusion to hoof structures was evident in both hind legs and was related to areas of abnormal bone conformation as well as to areas of abnormal ossification and calcification. Phalangeal and navicular bone hypoplasia were apparent as were soft tissue and joint anomalies. Although the etiology of the defects identified remains obscure, several theories are suggested, namely heritability, acquired defects and the possible teratogenic effects of clenbuterol.  相似文献   

Corynebacterium equi Infections in Horses, 1958-1984: A Review of 131 Cases   总被引：6，自引：0，他引：6       下载免费PDF全文

Zink MC  Yager JA  Smart NL 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(5):213-217

Of 131 cases of Corynebacterium equi infection in horses submitted for necropsy to the Ontario Veterinary College or Veterinary Laboratory Services, OMAF, Guelph, Ontario from 1958 to 1984, 115 were diagnosed as suppurative pneumonia, and of these 55 had associated ulcerative enterocolitis. Only five animals had intestinal involvement without pulmonary lesions. The remaining 11 cases included arthritis/cellulitis, skin abscesses and submandibular lymphadenitis. While the lung, intestine and associated lymph nodes yielded C. equi most frequently, in 21% of cases C. equi was also cultured from parenchymatous organs (spleen, liver or kidney) or blood. Corynebacterium equi infection accounted for 10% of all foals submitted for postmortem examination and 45% of all foals with pneumonia. Affected foals were one to four months of age. Submissions occurred between the months of May and August with a peak during July. There was a significantly greater prevalence of C. equi infection in Standardbreds when compared with other breeds. Of foals in this study, 36% were from farms which had had other horses succumb to this disease. Of the foals with pulmonary involvement, 21% did not have fever or clinical signs referable to the respiratory or gastrointestinal systems, findings which indicated that a large percentage of cases were subclinical.  相似文献   

The most complex magnetic field     

Kerr RA 《Science (New York, N.Y.)》1986,232(4758):1603

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Midgetman Missile Plans Generate Political Debate: A new ICBM has been designed for use as a strategic reserve, although the Pentagon may not intend to use it that way     

Smith RJ 《Science (New York, N.Y.)》1986,232(4755):1186-1188

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Greenhouse Warming still Coming: Estimates of the carbon dioxide-induced climate warming predict a large effect that could be doubled by increasing trace gases; some effects of the warming may already be evident     

Kerr RA 《Science (New York, N.Y.)》1986,232(4750):573-574

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