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41.
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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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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The archaeological record of Oldowan hominins represents a diverse behavioral system. It has been suggested that exploitation of lithic resources by Oldowan hominins was simplistic and represented mostly use of local sources of stone. Here we investigate the raw material selection and transport behaviors of Oldowan hominins reflected in the stone artifact assemblages from the Kanjera South Formation, South Rachuonyo District, Kenya. Using geochemical methods (ED-XRF) artifacts are linked to primary and secondary source outcrops throughout southwestern Kenya. These data show that hominins selected raw materials for transport at frequencies that are significantly different from their availability on ancient landscapes. Furthermore, a substantial proportion of the assemblage represents transport over relatively long distances (>10 km). Our study further suggests that in the early stages of stone tool use hominins used a wide variety of raw materials and selected these materials at some distance from their eventual discard locations. Early hominin behavior may have incorporated an understanding of raw material source distributions across a more extensive landscape than has been previously documented. This supports the growing perspective that Oldowan technology represents a more complex behavioral pattern than is usually associated with the beginnings of hominin tool use.  相似文献   
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We explore diet and mobility in Middle Archaic Florida using human burials and faunal remains from the Harris Creek archaeological site (8Vo24) on Tick Island. We conducted stable carbon and oxygen isotopic (δ13C, δ18O) analyses of 50 human enamel samples and strontium isotopic (87Sr/86Sr) analysis of a subset of 10. Most individuals (46/50) subsisted on local freshwater and terrestrial resources, with relatively depleted δ13C values (C3) and δ18O values matching those of central and north Florida water resources within the St. Johns River valley. Eight of 10 burials have local, within valley 87Sr/86Sr values. Two human burials yield marine δ13C and 87Sr/86Sr values, which we interpret as evidence for across valley movement from the coast. Another two individuals show depleted δ18O values, likely obtained from northern rivers. We also identified potential food resources and non-local foods from the Harris Creek faunal assemblage. We found six species with estuarine and marine habitat preferences; two of which, whelk and quahog, indicate that people of Harris Creek traveled to or traded with coastal areas.  相似文献   
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