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31.
Abstract: Climate change is already exerting significant pressure on humanity, but some people have the resources to cope, while others do not. What, then, determines vulnerability to climate change? This article presents a case study of one site of vulnerability in Egypt, known as the Mubarak Project villages on the shores of the Mediterranean. The soil of these villages is now undergoing rapid salinization, forcing farmers to apply sand to “elevate” their fields above the rising salty water table—but not all farmers can afford to buy the requisite sand. Accumulation by dispossession under the Mubarak regime has pushed some people towards the frontline of climate change, while at the same time denying them the resources to stay there. Using our case, we explore the connection between accumulation by dispossession and vulnerability to climate change and ask if an end to the former could reduce the latter in Egypt.  相似文献   
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The Bromme culture belongs to the Lateglacial, the period when people settled in the recently deglaciated Southern Scandinavia. Until now there have been only a few imprecise fix-points relating to the chronological position of this archaeological culture. This situation can now be improved with the aid of research results from a Bromme culture settlement at Trollesgave in SE Denmark. Using pollen and plant macrofossil data, Lateglacial lacustrine deposits containing waste material from the settlement can be assigned to the end of the climatically mild Allerød period. A series of 14C dates establishes the age of the settlement as c. 10 826 ± 49 14C years BP (12 871–12 590 cal yr BP). By correlation with climate data from the Greenland ice cores, the occupation can be assigned to the early part of the cold climatic zone GS-1, thus demonstrating that the global ice-core climate zones are not absolutely synchronous with the regional division into biozones.  相似文献   
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Homeless families face the economic and personal challenges of sparse employment opportunities and child care and nutrition needs, compounded by the loss of adequate housing. The Family Development Center (FDC) is a transitional housing program in Atlanta, Georgia, designed to provide young homeless mothers an opportunity to emerge from what may well be desperate circumstances and begin the journey to economic self-sufficiency. This paper describes the research on programs for homeless families and presents the results of a comprehensive look at the operation and effectiveness of the FDC program during its first 5 years of existence. The work shows that while many families were able to effect notable positive changes in their lives during and after taking part in the housing program, for some the recovery from homelessness was extremely difficult. For even the most successful formerly homeless families—those that secured employment, housing, and other social supports—the escape from welfare dependence and poverty proved very difficult. The paper concludes with a discussion of the implications for relevant public policy.  相似文献   
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In this paper we present a formal analysis that incorporates returns to transportation into a Ricardian framework to predict trade patterns. The important point gained from this analysis is that increasing returns to transportation, coupled with appropriate distances between trading partners, can be shown to reverse Ricardian predictions even when there are no international differences in tastes, technology, or factor endowments. Additional gains from trade may emerge from reductions in aggregate delivery costs owing to scale economies.  相似文献   
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By scientiometrically analyzing the physics-literature produced between 1925 and 1933 it is shown that the purely quantitative contribution of physicists subsequently emigrating from Germany to the literature produced by the physics community in this country was much lower than hitherto estimated. The actual figure is not in the range of 30%, as is generally assumed, but much nearer to 11%. Control analysis of three leading German physics journals and of memberships in the Deutsche Physikalische Gesellschaft confirms this result. Further investigation of university calendars shows that transferring these results to purely academic physics would amount to committing a “universalistic fallacy”. In academic physics emigré-physicists held a total of 15,5% of all teaching postitions. Differentiating the physics literature into various specialties allows further insights into the cognitive and social structure of the German physics community before 1933. Works of emigré-physicists are not randomly distributed over specialities; instead, the distribution reveals a nearly perfect correlation with what could be called “the specialty's paradigmatic age”. The spectrum begins with quantum theory, where future emigrants produced more than 25% of the literature, and fades away with acoustics, where their contribution amounts to less than 4%. The commonly accepted explanation of this phenomenon, which is based on the assumption that time of institutionalization of a specialty, “prestige” of that specialty, and entrance barriers for Jewish scientists are correlated, is falsified by two cases of non- or zero-correlation: by the very old specialties and by the technical disciplines. A new explanans is proposed which is based on the hypothesis of cognitive and social marginality being correlated and on a certain amount of cognitive marginality enhancing the disposition to innovative behavior and creativity.  相似文献   
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Social influence is one of the most important processes in human social interaction. Very often in human social interaction, influence is assimilative in that individuals become more similar to others they interact with. Nevertheless, cultural differences continue to remain in many realms of human life, for example, in the form of technological boundaries. Research on social influence points to a range of possible reasons for persistent cultural diversity, but there is much less clarity about the interplay of various factors and conditions for cultural influence with fundamental processes of social interaction at the micro-level. In this article, I show how agent-based computational modeling can be used as an approach for unraveling the complex interplay between simple first principles of interpersonal social interaction and emergent societal outcomes. I give a brief overview illustrating some of the main approaches agent-based modelers have developed in recent decades to understand conditions and processes of the emergence of cultural diversity. Models will be discussed that generate mainly cultural consensus as long-term behavior, but also models that generate clustering of cultural attitudes in geographical or social space, and models that imply cultural polarization with sharp cultural boundaries between emergent factions. It will be discussed how model dynamics depend on further assumptions, for example about random events, or the scaling of cultural attitudes, and what are further developments in the literature, possible future directions and challenges for the application of computational agent-based modeling in archeological research on cultural boundaries.  相似文献   
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