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Mobility is thought to be a significant source of Middle Paleolithic archaeological variability in the East Mediterranean Levant. However, models of Levantine Middle Paleolithic land-use have historically been based on rare and taphonomically sensitive evidence from a limited number of sites. Because lithic artifacts are the most ubiquitous archaeological remains available to the prehistorian, relationships between stone tool technology and mobility patterns can improve tests of hypotheses about prehistoric land-use strategies. This paper examines variation in Middle Paleolithic mobility strategies in the Levant from the perspective of core technology. A model linking expedient core reduction techniques and decreased mobility is adapted from one developed for late prehistoric contexts in the New World. Incorporating core data from numerous Levantine Middle Paleolithic assemblages, this study tests hypotheses about diachronic change, synchronic geographic variation, and possible hominin behavioral differences in mobility strategies.  相似文献   
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Robert G. Wallace 《对极》2009,41(5):916-951
Abstract:  The geographic extent, xenospecificity, and clinical course of influenza A (H5N1), the bird flu strain, suggest the virus is an excellent candidate for a pandemic infection. Much attention has been paid to the virus's virology, pathogenesis and spread. In contrast, little effort has been aimed at identifying influenza's social origins. In this article, I review H5N1's phylogeographic properties, including mechanisms for its evolving virulence. The novel contribution here is the attempt to integrate these with the political economies of agribusiness and global finance. Particular effort is made to explain why H5N1 emerged in southern China in 1997. It appears the region's reservoir of near-human-specific recombinants was subjected to a phase change in opportunity structure brought about by China's newly liberalized economy. Influenza, 200 nm long, seems able to integrate selection pressures imposed by human production across continental distances, an integration any analysis of the virus should assimilate in turn.  相似文献   
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Immigrant‐related policy indexes have become popular in both U.S. and European contexts, yet these projects boast distinct and divergent trajectories. European indices are characterized by rigorous conceptualization, specificity in elements of policy design (e.g., settings like fees or appeal process), and a variety of measurement strategies. By contrast, U.S. state‐level policy indices exhibit a lack of differentiation between immigration and integration policy and excessive generality in measurement and representation of policy instruments and settings, exacerbated in presenting a policy index as an aggregate count. This paper argues U.S. policy indexing can benefit from the European indexing experience. Following an overview of the state of each field, assessing concept differentiation, specification, and measurement in each, the paper illustrates how even the well‐conceived and specified European integration policy indices run into problems at the analysis stage. It presents a replication‐replacement study to illustrate divergent performance of highly correlated and conceptually agreeing indices, as well as methodological issues inherent to indices of low‐N, including using a policy index as a dependent variable and index selection absent a priori theorization. It concludes with suggestions for improving American immigration policy indices, as well as general observations on working with statistical power‐challenged indices and data limitations.  相似文献   
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Both the European Union and NATO are now committed in principle to substantial enlargement. It remains doubtful, however, how far member governments are making a success of further enlargement, let alone thinking through its strategic implications. Yet the process of dual enlargement will define the future security, political and economic structures of the European region. During the past year west European governments have extended promises of eventual membership to the western Balkan states and to Turkey; while the future positions of Ukraine, Russia, the Caucasus states and the southern Mediterranean associates all raise delicate policy issues. Hard choices remain to be made about the adaptation of these organizations to eastern enlargement, and about the management of relations with the near neighbours who will remain outside.  相似文献   
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