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Human transport of bones with high food values, and destruction of bones with low density values are the traditionally invoked explanations of the frequencies of bones in archeological contexts. The manner in which these two explanations have been used suggests archaeologists assume the explanations to be independent of one another. The transport explanation is operationalized as the modified general utility index (MGUI) of Binford, and the destruction explanation is operationalized with measures of bone density. Statistical correlation of the MGUI with bone density, while weak, indicates that many high utility bones have low density values while many low utility bones have high density values. Because low density bones tend to be destroyed more readily than high density bones, inferences of human utility strategies derived from bone frequencies and based on the MGUI may be inaccurate. The utility strategies suggested by three archaeofaunas are compared to bone density, and two of these faunas are shown to potentially be the result of differential destruction and not human transport as measured by the MGUI.  相似文献   
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As an initiative to increase cycling, bike to work (BTW) events emphasize a pragmatic approach in which people learn through sensory experience. Pragmatism contends that the lived experience of the commuter within fluid geographies of social and physical conditions informs commuting knowledge and behavior. I researched how bicyclists participate in the 2012 BTW event in Lake Tahoe (USA) and how these experiences facilitate the process of becoming bicycle commuters. My study included participant observations, interviews, video observations, and route mapping. I analyzed this data with thematic and narrative analyses. I find that the BTW event illuminates bicycling, a normally invisible practice in a car world, and creates temporary bicycle-friendly spaces that provide the embodied experience and knowledge of bicycle commuting within context. Through this lived experience, participants can break free from unconscious car-based patterns and become embodied bicycle commuters who engage in active renegotiations of their commuting practices.  相似文献   
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Spatial clusters contain biases and artifacts, whether they are defined via statistical algorithms or via expert judgment. Graph-based partitioning of spatial data and associated heuristics gained popularity due to their scalability but can define suboptimal regions due to algorithmic biases such as chaining. Despite the broad literature on deterministic regionalization methods, approaches that quantify regionalization probability are sparse. In this article, we propose a local method to quantify regionalization probabilities for regions defined via graph-based cuts and expert-defined regions. We conceptualize spatial regions as consisting of two types of spatial elements: core and swing. We define three distinct types of regionalization biases that occur in graph-based methods and showcase the use of the proposed method to capture these types of biases. Additionally, we propose an efficient solution to the probabilistic graph-based regionalization problem via performing optimal tree cuts along random spanning trees within an evidence accumulation framework. We perform statistical tests on synthetic data to assess resulting probability maps for varying distinctness of underlying regions and regionalization parameters. Lastly, we showcase the application of our method to define probabilistic ecoregions using climatic and remotely sensed vegetation indicators and apply our method to assign probabilities to the expert-defined Bailey's ecoregions.  相似文献   
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This article examines the portrayal of non-North Koreans in North Korean textbooks to assess the influences on the formation of North Korean identity, and how such identity formation is important in Kim Jeong-il's retention of power. This study not only looks closely at textual representations; it also examines how political and ideological changes in North Korea had a critical influence on these texts. The study encompasses both lexico-grammatical analysis and the analysis of textual and visual images, based on an examination of six North Korean language textbooks published from 1954 to 2000. It demonstrates that North Korean identity is defined through the portrayal of non-North Koreans, particularly enemy others. The portrayal of non-North Koreans facilitates the formation of a solid North Korean identity – an identity that entails serving their political leaders, remaining vigilant against threats to their country, and liberating South Koreans from poverty and oppression by America and its puppet states.  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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