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PAUL D. WILLIAMS 《International affairs》2007,83(6):1021-1038
This article attempts to clarify some of the central questions and distinctions that provide the necessary backdrop for thinking in a sophisticated way about security in Africa. Drawing on the developing Critical Security Studies literature it suggests that an understanding of security based on people, justice and change offers the surest route to a stable future. It then sketches preliminary answers to some fundamental questions, namely: whose security should be prioritized? How have security dynamics in Africa been influenced by the wider processes driving world politics? What clusters of threats are the most salient? Where do such threats have the most pernicious effects? Which actors are best placed to alleviate those threats? And what sort of institutions should be built to assist in that process? The role of outsiders concerned with promoting security on the continent should be to try to ensure that as many Africans as possible are able to voice their opinions on these crucial issues. 相似文献
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Having been adopted by legislatures in over a dozen states, postsecondary merit aid programs are largely concentrated in the southeastern United States. The observed clustering pattern seems to support previous evidence that policies spread between proximate states, a phenomenon referred to by political scientists as policy diffusion. Often, however, policy diffusion is not complete, and one or more states in a region fail to adopt. By interviewing policymakers throughout the southeastern United States—including actors in the three states in the region without merit aid—the study addresses the following question: Why do diffusion pressures lead to adoption in some states but not in others? Studying state “hold‐outs” promises not only to uncover the reasons for failed legislation in specific state contexts but also to better our understanding of the limits of diffusion theory. 相似文献
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L. Martin‐Francs M. Martinon‐Torres A. Gracia‐Tllez J. M. Bermúdez de Castro 《International Journal of Osteoarchaeology》2015,25(4):564-573
We present the palaeopathological analysis of a right fourth metatarsal (ATD6‐124) recovered from the Atapuerca–Gran Dolina site (Spain). This fossil, ca. 1 Ma, belongs to Homo antecessor, the earliest known European hominin species. The metatarsal exhibits a proliferative lesion on its medial periosteal surface. Periosteal reaction can be the bone response to a wide number of injurious processes. We describe a lesion on the basis of macroscopic and microscopic analyses, including microtomography and scanning electron microscopy. Externally, the osteoblastic lesion presents a highly porotic and disorganised morphology. Internally, we observe a series of micro‐fractures on the compact bone that do not affect the medullary canal. We provide a differential diagnosis and suggest that the ATD6‐124 lesion could correspond to a pedal stress fracture, also known as fatigue or march fracture. Stress fractures have been related to a load increase and muscular fatigue. This type of fracture has been widely reported in the foot of soldiers and athletes, which are usually engaged in strenuous, excessive or prolonged locomotive activities. Despite its high frequency in these groups, stress fractures have not been reported as such in fossil collections, with the exception of a metatarsal belonging to the Sima de los Huesos site (Atapuerca). Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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PAUL CLAVAL 《The Canadian geographer》1973,17(2):103-112