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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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在朝鲜战争起源的问题上,学术界一直存在着争论.一些西方学者认为,朝鲜战争是在苏联、中国和朝鲜周密的共谋下发动的,这种说法后来被称为"三国同谋论".但这种说法与最近公开的资料并不相符.本文以中国、苏联的新资料为依据对以往的"三国共谋论"进行了反驳,并得出结论:中国不仅没有参加策划朝鲜战争,而且在一定程度上对发动这场战争持不赞成的态度. 相似文献
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Peter George Maxwell‐Stewart 《European Legacy》1999,4(2):74-76
Francis Bacon. By Perez Zagorin (Princeton, NJ: Princeton University Press, 1998) xvi + 286 pp. $29.95, £19.95
Francis Bacon: The History of the Reign of King Henry VII. Edited by Brian Vickers (Cambridge, UK: Cambridge University Press 1998) xlv + 284 pp. £40.00 cloth 相似文献