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Latham MC 《Africa today》1993,40(3):39-53
Issues surrounding the spread of acquired immunodeficiency syndrome (AIDS) in Africa are summarized. Subjects considered include the disease's origins, proportion of the population infected with the human immunodeficiency virus (HIV) and AIDS, the problems in caring for children orphaned by the disease, innovations in drug treatments discovered by African scientists, the spread among women, and the difficulties inherent in incorporating Western-based policy and aid provisions into the African context. 相似文献
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C. ORTON 《Archaeometry》1993,35(2):169-184
This paper reviews the ways in which assemblages of pottery have been quantified throughout the twentieth century, and the use to which such data have been put. The values of various ways of quantifying pottery are compared, and a theoretical basis for the comparison of assemblages is described. Finally, the practical steps that need to be taken to make best use of the theory are set out. 相似文献
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Among the manifestations of radioactive decay which can be etched to optical visibility on the surface of mica are tracks from nuclei recoiling from alpha emission, called ‘alpha-recoil tracks’. If, beforeetching, the mica is heated to temperatures of the order of 600°C, all evidence of these tracks is annealed from muscovite mica in a few minutes. Alpha activity observed on mica from pot sherds, from stones surrounding fire places, from fire pits, and fired daub may constitute an alpha-recoil track clock which started at the moment of the last firing of the artifacts. 相似文献
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Research on policy impact has increasingly focused on the practical application of social science research. This paper outlines four roles—substantive expert, information processor, change agent, and scholar—which have helped to increase the potential usefulness of our research while maintaining linkages to the academic community. This paper suggests the general nature of these roles and suggests specific implementation strategies, which need to be pursued as an early and continuing aspect of the research enterprise. Balancing these multiple roles presents several analytical and ethical difficulties, but helps to establish credibility in both the scientific and policymaking communities. 相似文献
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