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81.
The pathways leading to the adoption of cereal cultivation and pastoralism in West Africa are poorly understood. In order to elucidate the transition to food production during the Late Stone Age in Mali’s Tilemsi Valley samples of ancient and modern human and animal remains were selected for carbon and oxygen isotope analysis. Our results indicate the inhabitants of Karkarichinkat Nord (KN05) consumed considerable quantities (85%) of carbon derived from C4 plants, either directly in the form of C4 grasses such as wild Panicum sp. and possibly domestic Pennisetum sp. or indirectly through the consumption of C4 grazers such as Bos sp. and Ovis sp.  相似文献   
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Numerous studies have shown associations between public open space and a variety of health outcomes. Yet the extent to which firm conclusions and planning policy recommendations can be drawn from this body of work depends on how public open space availability has been measured and reported. Other researchers have highlighted potential issues with the way that public open space has been measured but have not systematically assessed the extent of this problem. This paper provides a comprehensive critical review of studies of public open space and health conducted in Australia to identify and compare public open space measurement and data treatment. Our analysis showed wide variation in how public open space was measured, as well as a lack of consistency in reporting public open space exposure measures and under‐reporting of measurement methods. We find that such tendencies limit how much these studies can be compared and contrasted with each other. The corollary of that finding is that without more detailed reporting of exposure measures, it will be difficult to establish an evidence base that informs planning for healthy, liveable environments. In response, we develop and present a checklist for reporting public open space exposure to address this challenge.  相似文献   
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In this paper I reflect upon encounters with ‘young people’s participation’ during ethnographic research on girlhood and sexual agency with teenage girls in Tanzania. I argue that methodology which centralises participants’ experiences is particularly important in research on issues related to sex and sexuality, where young people’s voices are often disregarded or downplayed. However, such an approach might run up against a number of practical challenges. This paper draws on fieldwork conducted in two sites during 2014 and 2015 to show that attention to the networks of relationships within which young people are embedded and the structural conditions which might generate or obstruct sexual agency is essential for research which seeks to promote their meaningful participation.  相似文献   
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A canid skull and mandible, dated to the late neolithic, produced a series of measurements which indicate an animal significantly larger than any dog recovered from this period. The skull showed evidence of healed trauma with associated asymmetry. Metrical and morphological criteria have been applied to identify the remains as those of wolf Canis lupus, and the results of these tests are inconclusive. The possibility that the remains are of a large dog, Canis familiaris, is discussed, together with the implications that this may have for the archaeological consideration of this species.  相似文献   
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The causes and implications of the regional variations in the spread of the incipient agriculture in Europe remain poorly understood. We use population dynamics models to study the dispersal of the Neolithic in Europe from a localised area in the Near East, solving the two-dimensional reaction-diffusion equation on a spherical surface. We focus on the role of major river paths and coastlines in the advance of farming, to model the rapid advances of the Linear Pottery (LBK) and the Impressed Ware traditions along the Danube–Rhine corridor and the Mediterranean coastline, respectively. We argue that the random walk of individuals, which results in diffusion of the population, can be anisotropic in those areas and hence lead to an effective advection. The standard reaction-diffusion equation is thus supplemented with an advection term, confined to the proximity of major rivers and coastlines. The model allows for the spatial variation in both the human mobility (diffusivity) and the carrying capacity, reflecting the local altitude and latitude. This approach can easily be generalised to include other environmental factors, such as the bioproductivity of landscapes. Our model successfully accounts for the regional variations in the spread of the Neolithic, consistent with the radiocarbon data, and reproduces a time delay in the spread of farming to the Eastern Europe, Britain and Scandinavia.  相似文献   
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