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"The spread of HIV-1 in the United Kingdom is simulated by a model which integrates behavioural and epidemiological processes within a multi-regional population projection framework and represents the spatial heterogeneities in the distribution of HIV which have significant effects on transmission patterns. Analyses determine the significance of different parameters in contributing to prediction uncertainty and highlight the importance of behavioural change and international population movements."  相似文献   
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Current federal hazardous and low-level radioactive waste management policies (under conjoint federalism) fail to balance national concerns for consistency with state concerns for equity, discretion, and adequate resources. Congress should expand conjoint federalism to permit states to charge differential fees on imported hazardous waste as it does for low-level radioactive waste. For low-level radioactive waste, clarification of the "take title" issue makes the present framework for state discretion implementable, given sufficient time.  相似文献   
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The paper examines the ancestry of Europeans in Sydney and that of the two largest non European groups. Spatial divergence occurs between the English, Scottish and Irish, and divergence from those of Australian ancestry. Residential persistence across generations occurs with persons of Greek, Italian, Maltese and Dutch origins, but not spatial segmentation. While there is greater language persistence in Greek and Italian second and third settlement concentrations, few third generation persons speak their ancestral language at home. The Chinese and Lebanese are compared with Greek and Italian ancestry in their areas of strongest representation. First generation Chinese are evident in areas of both low and high socioeconomic status, but without third generation language persistence. An evolving ethnic mix in Sydney is indicated.  相似文献   
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"Although nation-states assume territorial, political and cultural boundedness, their boundaries are not uniform barriers, but rather are characterized by varying degrees of openness and closure to international migrants. The manipulation of the permeability of these boundaries constitutes the politics of admission and exclusion....This paper provides a discussion of the complex economic, political and social forces impinging on the politics of admission and exclusion and an analysis of how these forces have been operating in a particular historical and geographical context to determine the admission of international migrants into national territory and community....There are signs that the integration of nation-states into regional blocs such as the EC is shifting the politics of admission and exclusion practised by the dominant member countries to the supra-national scale."  相似文献   
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