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81.
Zooarchaeologists have often employed studies of bone fracture morphology as a means of understanding past human cultural activity, and various methodological approaches have been developed for analyzing archaeological broken bone assemblages. It is widely understood that bones degrade over time, however, few studies have attempted to define and quantify the rate at which bones degrade and fracture morphologies change. This study examines degradation in frozen bones (−20 °C) and bones exposed to hot (40 °C) dry conditions. These two simulated environmental conditions represent extreme real-world climates, and allow for an actualistic understanding of the rates of degradation that bones experience in nature. When frozen, bones degrade slowly but significantly, and demonstrate measurable differences in samples frozen for 1, 10, 20, 40, and 60 weeks. In hot, dry conditions, bones degrade very quickly, and demonstrate measurable differences after 1, 3, 7, 14, and 21 days. These data allow for a more detailed understanding of the relationship between the cultural and natural processes that result in bone fracture, and the time period during which bones can be expected to maintain fresh fracture characteristics. This research also has implications for understanding human subsistence and survival strategies and for interpreting the archaeological record.  相似文献   
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Body mass index (BMI) values reflect the net balance between nutrition, work effort, and calories consumed to fight disease. Nineteenth-century prison records in the United States demonstrate that the BMI values of blacks and whites were distributed symmetrically; neither underweight nor obese individuals were common among the working class. BMI values declined throughout the nineteenth century. By modern standards, however, nineteenth-century BMIs were in healthy weight ranges, though the biological living standards in rural areas exceeded those in urban areas. The increase in BMIs during the twentieth century did not have its origin in the nineteenth century.  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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Much of the excitement generated in Britain since 2007 by the York Archaeological Trust’s excavations of the city’s Hungate neighborhood, which Benjamin Seebohm Rowntree characterized as a “slum” in his pioneering poverty survey of 1901, derives from the unexpected volume and variety of material evidence uncovered about life in a poor community within a modern industrial city. Such material evidence and its often uncertain relationships to other historical data can enhance analysis by complicating understanding of the past, rather than echoing conventional wisdom. Findings from Hungate can thus contribute to nuanced understandings of urban social disadvantage not only at the neighborhood level in this one particular British city, but at the larger scales of analysis that encompass the growth of cities and interacting urban regions in Britain and around the world during the nineteenth and twentieth centuries. These understandings have contemporary relevance for a world in which over half of humanity now lives in urban areas, as misconceptions about “slums” continue to undermine efforts to reduce urban inequality.  相似文献   
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Abstract

This special issue is presented as a thematic issue devoted to tropical coastal and island tourism. Included in the issue are articles on (eco)tourism in Madagascar, collaboration theory and tourism partnership models on an Indonesian island, development pressure and resilience on a Malaysian island, a survey of cruise passengers in Colombia, perception and limits to development in Costa Rica, and perception and reality on Pitcairn Island. Placed within theoretical or conceptual frameworks, these case studies can be applied to development challenges of tropical coastal and island destinations worldwide.  相似文献   
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