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Homeless and street children are commonly portrayed in the academic and welfare literature as a prime category of ‘children at risk’. They have attracted world‐wide attention due to rising numbers in cities of the Western and developing world coupled with a discourse of childhood that ascribes risk to poor urban children unaccompanied by adults on the streets. This paper presents a critique of views about homeless and street children that rest upon an unhelpful blanket generalization of risk and, more specifically, that adopt polemical or categorical statements about homelessness as the most salient risk factor for poor health. Current research is distancing itself from a discourse that sets global characteristics for a ‘street lifestyle’, aiming instead to contextualize research on street children. Many studies have also questioned the stereotypical expectation that homeless children are the most vulnerable in deprived environments, arguing that poverty, not homelessness per se, carries the most significant risks to children's health. A risk discourse is unhelpful where it promotes a stereotype of vulnerability about children, resulting in further discrimination and social exclusion; it is most helpful when it focuses attention on ways to negotiate adverse situations. Some challenging academic and practical questions need to be raised regarding risk assumptions and risk assessment.  相似文献   
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This article examines the social effects of contract farming of export horticulture among smallholders in Meru District, Kenya. During the 1980s and 1990s, contracting was popularized by donors and governments alike as a way to reduce poverty and increase opportunities for self–employment in rural areas. Considerable research has documented the tensions in social relations that emerge in such cases, giving rise to gendered struggles over land, labour, and income in the face of new commodity systems. This article highlights similar tendencies. It suggests that men’s failure to compensate their wives for horticulture production has given rise to a string of witchcraft allegations and acts, as the wealth engendered by horticultural commodities comes up against cultural norms of marital obligation. While witchcraft accusations can expose women to risks of social alienation and financial deprivation, witchcraft nevertheless remains a powerful weapon through which women can level intra–household disparities and, more broadly, challenge the legitimacy of social practice. In Meru, witchcraft discourses are a vehicle through which gendered struggles over contract income are articulated and contested, and through which the social costs of agrarian transition become apparent.  相似文献   
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This paper explores the reasons why cities are often major centres of innovation, even in some less favoured regions and countries. It starts with an anatomization of the dominant factors that explain why key less favoured settings developed 'new economy' clusters through institutional interaction with Silicon Valley. The analysis concludes that public research resources and private commercialization funding are central, supported by a wide array of private but few public innovation support services. It then examines a number of cases from cities in less favoured regions and countries where innovation has occurred. The conclusions are that the research-venture capital model is present and explains innovation in each case. However, in some cases public venture capital has to substitute for private due to market failure, or a phenomenon termed 'Silicon Valley Offshore' has been induced. Cities are innovative where they concentrate the desired scientific and investment knowledge capabilities.  相似文献   
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The aim of this proposal is to present an original approach to the study and preservation of rock art caves. A multidisciplinary study of cave wall alteration will be performed to understand the impact of environmental context on the evolution of wall surfaces. The approach involves the choice of a cave with characteristics similar to painted caves in the studied area (Vézère Valley in Dordogne, France): e.g., cave wall alteration, lithology, morphology, etc. This selected cave is intended to become a laboratory cave, monitored for the acquisition of chemical, physical and biological environmental data on bedrock, air and fluids along with their characteristics. A cave without art or archaeological interest has been chosen specifically to conduct experiments, to make in situ analysis and to obtain samples. The results are to be completed by specific observations in several other caves and compiled in a database.  相似文献   
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