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961.
Abstract

China's position in the world economy during the past half-century provides vital information for investigating the relation between politics and trade. Although there is a substantial number of studies in this area, the current study extends the literature in at least three ways: (1) it is one of the first studies that investigates the problem of a potential sample selection bias—as a result of the fact that countries taken up in the analysis are not randomly sampled from all countries in the world; (2) it considers third-country effects that follow from the fact that China's relation with any two countries is affected by the relation between these countries themselves; and (3) it tests the impact of five political arrangements simultaneously, which is more comprehensive than any former study. By using data as to 78 of China's trade partners over the 1950–2002 period, this study provides empirical evidence for the hypotheses that the establishment of diplomatic relations, cooperation, visits of heads of states and political system similarity are associated with greater trade flows. The hypothesis that member countries of a Preferential Trading Agreement have had smaller trade flows with China, which is no member of any of these Preferential Trading Agreements, is not supported by the results.  相似文献   
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An experimental study of the natural sampling of trace signals from explosives concealed upon the human body was performed by taking proper account of the thermal behavior of the air surrounding the human body and the particles therein. Experiments were conducted in a dispersal chamber to identify variables affecting the detectibility of concealed RDX and TNT patches. Movement by human volunteers was found to enhance the available explosive trace signal above a baseline level. Clothing blocked some of this movement-generated trace signal. The detected signal levels were also found to vary significantly from volunteer to volunteer, indicating that human variability is an issue in explosive trace detection. Further, under the conditions studied here, the detectibility of RDX and TNT was dependent upon the efficient sampling of contaminated particulate matter, not the vapor phase. The present results are now being applied to the design of a practical, nonintrusive trace detection portal for aviation security screening and related applications.  相似文献   
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967.
The National Health Service (NHS) in England and Wales has embarked upon a radical and far–reaching programme of change and reform. However, to date the results of organizational quality and service improvement initiatives in the public sector have been mixed, if not to say disappointing, with anticipated gains often failing to materialize or to be sustained in the longer term. This paper draws on the authors' recent extensive research into one of the principal methodologies for bringing about the sought after step change in the quality of health care in England and Wales. It explores how private sector knowledge management (KM) concepts and practices might contribute to the further development of public sector quality improvement initiatives in general and to the reform of the NHS in particular. Our analysis suggests there have been a number of problems and challenges in practice, not least a considerable naïvety around the issue of knowledge transfer and 'knowledge into practice' within health care organizations. We suggest four broad areas for possible development which also have important implications for other public sector organizations.  相似文献   
968.
In 7 of 15 cases of sudden infant death syndrome (SIDS), distinct periventricular fatty metamorphosis of the neuroglia could be demonstrated by a histological staining technique. None of the six children (under 1 year of age) used as a control group whose cause of death was not SIDS showed this morphological change. Thin-layer chromatographic analysis of the lipids accumulated in the glial cells in SIDS established a high amount of esterified cholesterol whereas the content of esterified cholesterol in the control group was low. We presume that fatty metamorphosis of the neuroglia represents the morphological substrate of a metabolic disorder of the sensitive, immature glia of the periventricular white cerebral matter caused by various kinds of damage.  相似文献   
969.
The field of policy analysis encompasses a greater diversity of practices than is commonly appreciated. Many recent revisions agree with the postmodern dictum that analytic studies are socially constructed and propose some form of discourse for formulating policy. This article compares three theoretical perspectives on discourse: analytic discourse, which draws on multiple theories and data sources; critical discourse, which emphasizes critical reflection and links evidence to value discussions; and persuasive discourse, which focuses on the role of ideas and persuasion by policy entrepreneurs. Analytic discourse has had the most impact on the practice of analysis, but the other two literatures have had some influence and address important issues. Critical discourse is sensitive to the structural biases in policy research, and persuasive discourse links the practice of analysis to opportunities in the policy arena. The author seeks to make us more conscious of alternative theories, while emphasizing the role of discourse in all three models and the linkages between policy design and the policy process.  相似文献   
970.
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