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101.
The Central Institute for Brain Research was founded in Amsterdam in 1908 as part of an international effort to study the nervous system with multiple institutions and various disciplines. The development of research in the past hundred years at the Brain Institute has hardly been documented. We analyze the history of this institute by means of brief portraits of its directors and their main research topics. It appears that each director introduced his own branch of neuroscience into the institute. Initially, mainly comparative neuroanatomical data were collected. Following the Second World War, the multidisciplinary approach slowly developed with research programs on systems neuroscience, neuroendocrinology, and brain disorders. Every new director introduced new approaches to the study of the brain and thus played an important role in keeping brain research in the Netherlands at the international forefront where it has been ever since its foundation in 1908.  相似文献   
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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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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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