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ABSTRACT.  This study estimates a series of random parameter logit models of the college-to-work migration decisions of technology graduates and holders of doctorates within the United States. We employ detailed information on the migration-relevant characteristics of individuals, as well as on their actual origins and destinations at the metropolitan scale. In addition to its obvious implications for "brain drain" policies in U.S. metropolitan areas, the study demonstrates the richness of the random parameters technique for behavioral-geographic analysis. We find that science and technology graduates migrate to better educated places, other things equal; that PhD graduates pay greater attention to amenity characteristics than other degree holders; and that foreign students from some immigrant groups migrate to places where those groups are concentrated.  相似文献   
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This paper presents the initial results of excavations at Kanjera South, located on the Homa Peninsula in Western Kenya. Since 1995, our exploration of this locality has yielded a combination of artefacts and well preserved faunal remains in a sedimentary context that also allows for environmental reconstruction. Here we examine the history of exploration of Kanjera and its significance in the development of palaeoanthropological research in East Africa. We also summarise our findings from the recently discovered Oldowan site. Taphonomic analyses suggest that the archaeological layers were formed at least partially by hominin activity. Artefacts made from a wide variety of raw materials are abundant, as are animal bones. Results of our first analyses confirm that Oldowan hominins had considerable behavioural flexibility and occupied a range of habitats.Cet article présente des résultats préliminaires de nos fouilles au site de Kanjera South, situé sur la péninsule de Homa au Kenya occidental. Depuis 1995 nos explorations à cette localité ont produit une combinaison des outils lithiques et des restes fossils dans un bon état de conservation venant d’un contexte sédimentaire qui permet également les reconstitutions paleoenvironnementaux. Ici nous examinons l’histoire de l’exploration de Kanjera et de son importance dans le développement de la recherche paleoanthropologique en Afrique de l’Est. Nous récapitulons également nos résultats du gisement récemment découvert d’Oldowan. L’étude taphonomique suggère que les couches archéologiques ont été formées au moins partiellement par l’activité des hominins. Les objets fabriqués faits à partir d’une grande variété de matières lithiques sont abondants, de même que les os animaux. Les résultats de nos premières analyses confirment que les hominins d’Oldowan ont eu une flexibilité de comportement considérable et ont occupé une gamme d’habitats différents.  相似文献   
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Two stone flakes partly covered in birch-bark-tar and a third without tar on it were discovered in fluvial gravel and clay in central Italy, in association with the bones of a young adult female Elephas (Palaeoloxondon) antiquus and several micromammals. The probable chronology of the stone flakes is compatible with the late Middle Pleistocene suggested by the site's small mammals and geological context. The fauna indicates a cool stadial episode before isotope stage 6. That age means the flakes are the oldest ever found hafted with tar and indicate a greater capacity for late Middle Pleistocene hominins to utilize raw materials available during cold phases.  相似文献   
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In Canada and elsewhere, there is a growing belief that farming and rural communities have become effectively disconnected from one another. While attention to recent media reporting suggests that incidences of conflict are now as common as examples of support and collaboration, it is suggested that many examples of complementarity remain. These evolving relationships may, however, be linked to the nature of specific farm development trajectories. Such possibilities warrant empirical examination, with attention to known diversity in the family farm sector. This paper reports on an empirical investigation of farm and community linkages in North Huron County, Ontario. The paper builds upon a recent investigation of change in family farming in this region and seeks to document the ways in which local farmers continue to look to their rural communities for support of various kinds. Data are drawn from a survey of farmers in Ashfield and Colborne Townships in 1999. The research explores community linkages around three dominant themes: participation in organisations, purchasing and perceptions and experiences of community support for farming. The findings indicate the persistence of strong linkages between farms and local communities in the study region but point to a potential tendency for disconnection between farms pursuing aggressive expansion and local community organisations and businesses. There is some evidence that jobs and a variety of farm household considerations may form key linkage points between the two sectors, with the importance of these mediated by farm business trajectories and the family life course.  相似文献   
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Introduction     
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The English Church Missionary Society (CMS) dispatched a contingent of missionaries to Egypt in 1825. This article analyses the methods and impact of that contingent. The schools that the CMS missionaries introduced are cast not as vehicles of enlightenment — as is frequently the case in mission historiography — but as technologies of power. Specifically, the article recounts how the head of the mission, the Reverend John Lieder, deployed Lancaster schools among the Coptic Christians of Cairo to effect not merely a spiritual, but further, a cultural conversion of this Orthodox community. Lieder, his predecessors, and his contemporaries in the Mediterranean field sought to instil in the Copts the "evangelical ethos" of industry, discipline, and order. The article links this CMS project of cultural conversion to the process of state-building in Egypt. Indeed, Lieder was a pioneer purveyor of technologies of power that would prove indispensable to late-nineteenth-century elites in their efforts to produce, in the subaltern strata of Egyptian society, industrious and disciplined political subjects resigned to their lowly positions in the Egyptian social order.  相似文献   
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