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51.
Archaeological research has made significant contributions to the study of the African Diaspora in the Caribbean, but until recently researchers neglected the French islands. This paper reports on archaeological fieldwork at Habitation La Mahaudière in Guadeloupe, focusing on the economic and social lives of plantation laborers and exploring articulations between local realities at this sugar plantation and broader historical process of the Caribbean region and the French colonial world.  相似文献   
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Until now, the oldest known human hair was from a 9000-year-old South American mummy. Here we report fossil hairs of probable human origin that exceed that age by about 200,000 years. The hairs have been discovered in a brown hyaena (Parahyaena brunnea) coprolite from Gladysvale cave in South Africa. The coprolite is part of a hyaena latrine preserved in calcified cave sediment dated between 195,000 and 257,000 years ago. This find supports the hypothesis that hyaenas accumulated some of the early hominin remains found in cave sites, and provides a new source of information on Pleistocene mammals in the Sterkfontein Valley.  相似文献   
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Soil multi-element analysis is now a routine technique employed to help answer questions about space use and function in and around archaeological sites. The pattern of enhancement of certain elements, including P, Pb, Ca, Zn, and Cu, has been shown by numerous studies to correlate closely with the archaeological and historical record. Interpretation of these soil signatures, however, has generally been more problematic. One approach to the problem has been the use of ethnographic or “known” sites to guide interpretation, but how confidently can results from one site be extrapolated to another? This study of abandoned farms tests the site specificity of soil multi-element signatures of past space use through the use of discriminant models. Data analysis suggests that one to one comparisons of similar sites are much less accurate (38% accuracy) than comparisons based on a wider range of sites (59.3% accuracy), even when the latter have contrasting geology. The results highlight the importance of individual anthropogenic practices during occupation and abandonment in the development of diagnostic soil geochemical signatures.  相似文献   
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This article investigates how presidential policy attention is allocated across policy tools and whether there is a channeling of tool use by policy area. I also examine whether there is evidence of disproportionate information processing within presidential policy attention allocation and whether it is common across presidential policy tools. Presidential messages, hearings on administrations' legislative proposals, amicus briefs, and executive orders are employed to capture presidential policy tools. The allocation of attention via these four instruments is examined from 1957–2007 in the policy areas of defense and foreign affairs, macroeconomics, banking and commerce, civil rights, law and crime, and labor and immigration. I find that there is a canalization of presidential policy attention by instrument, and that the opportunity structure of policy tools shapes attention allocation. Additionally, I find evidence for punctuated equilibrium theory in the allocation of presidential policy attention via these four tools. When presidents do shift their attention to an issue area, they often attack the issue with some coordination of their policy instruments.  相似文献   
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A key area in the analysis of urban structural evolution is identifying discontinuities. Effective analysis could improve long‐term forecasting and provide a better understanding of how to steer an urban system toward a desirable future state. We use a simple aggregate retail model to demonstrate an algorithm for identifying discontinuities in model parameter space. Explorations of retailing in both Greater London and South Yorkshire in the United Kingdom illustrate how understanding a system's potential for discontinuity can provide insights for both policy makers and retail businesses. The Harris and Wilson model, described in the section so‐named, is used as a simple archetype to illustrate the new framework. This model can be developed in a straightforward way to incorporate further refinement. In “ Executing the model and visualizing the results ,” we describe a single model run and in “ Investigating discontinuities ,” we explain our framework for detecting and analyzing discontinuities. “ Identifying discontinuities in the London retail system ” shows the results of applying this methodology to the Greater London retail system, and in “ Practical applications ,” we explore the policy applications for this technique as related to the decline of town centers in the South Yorkshire retail system. Some concluding comments are offered in “ Conclusions .”  相似文献   
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Since 2005, a burgeoning wave of Chinese investments has set off a new ‘minerals boom’ in the Australian iron ore and coal mining sectors. While normally a welcome development, the state-owned and strategic nature of the investors has raised concerns in Australia about how these should be regulated. As a result, in February 2008 the Australian government declared an intention to more closely screen foreign direct investment (FDI) from state-owned sources, which both supporters and detractors alike have claimed is evidence of ‘resource nationalism’ in Australia's approach towards its trade and investment relationships with China. This article challenges this understanding through an examination of the characteristics of Chinese mining FDI, the dilemmas these present to the Australian government, and the relatively restrained nature of its response. Through this, Australia's FDI policy is explained as a defensive move against the potential for strategic behaviour by Chinese investors resulting from their state ownership, rather than any national program to subject minerals trade and investment to political control. On this basis, the article argues that Australian government policy instead evidences a ‘resource liberalism’ approach, which intends to ensure that the governance of Australia's minerals trade and investment with China remain market-based processes.  相似文献   
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