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Carbon and oxygen isotope ratios in the shells of the freshwater Unio mollusc yield information on the isotopic composition of the water in which the shell was formed, which in turn relates to climatic conditions prevailing during the bivalves’ life span. Here we analysed shells from one modern Unio, from a modern lake shore in Anatolia, and 4 subfossil Unio shells from Çatalhöyük (dated between 7200 BC and 5000 BC, Neolithic and Chalcolithic periods). Sequential carbon and oxygen isotope analysis along the surface of the shells provides information on seasonal or shorter-term variability of lake waters during the lifetime of the organisms. δ18O values of the modern shell are consistent with it being collected from a dammed portion of the Seyhan River that does not undergo intensive summer evaporation. This is in contrast to many of the surface water bodies in Anatolia which suffer extensive evaporation in the arid summers. δ18O values of the subfossil shells from the Çatalhöyük middens indicate that the bivalves came from lakes which evaporated extensively during the summer months but were replenished by high winter rainfall, suggesting that the subfossil shells lived in relatively small lakes or ponds. Stable isotope analysis along the growth of freshwater bivalves is one of the few methods for investigating seasonal water fluctuations in the past. These results may alter current interpretations on the environment of Çatalhöyük during the Neolithic, although more work is needed to confirm these initial findings.  相似文献   
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In this paper, I explore cultural discourse, gender and the subjectivities of local people on the frontier of empire in mid‐20th century southern Africa. Using the example of Nekwaya Loide Shikongo, a prominent woman from Ondonga in northern Namibia (the colonial “Ovamboland”), and an epic poem on the deposed King Iipumbu yaShilongo that she performed in 1953, I discuss how gender was constituted and mediated. The narrative of a remarkable woman’s life and her poetry is told to understand how gender in relation to other forms of identity was constructed in different cultural discourses. I argue that both the Christian mission’s cultural discourse and the South African colonial administration’s efforts to masculinise the “native” political authority gendered Owambo elite women whose identities had previously included “gender” only as a rather contingent component. The example of Loide Shikongo, however, also shows that many Owambo continued to pursue heterogeneous, and sometimes ambiguous, strategies in their claims to Christian models of modernity.  相似文献   
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Computed tomography (CT) was first applied in the early 1970s and introduced subsequently a new perspective towards anatomical imaging. In the last decade, high-resolution CT (HR-CT) had a high impact on anthropology and paleoanthropology through its ability to define and explore subtle differences in hard tissue structures in fossil and extant humans and nonhuman primates. CT is very suitable for unique fossil material, because it is destruction free and the original material stays intact while the internal structures are digitized. The imaging yields a virtual copy of the object, which can be used for the generation of detailed copies of original fossil material. CT data allow multiple studies in parallel and independently on specimens which are not commonly accessible. Diverse CT systems with different performance characteristics as designed for different functions can make it difficult for a researcher to choose the most appropriate CT system and to check the image quality of CT scans. The physical principles involved in CT imaging and the principles of signal processing and computer graphics can help to choose the best scan setting and the most suitable CT system for a study. Quantitative and qualitative analysis can also be improved and comparisons between different studies can be facilitated when the above mentioned principles are taken into account. In the following, I will give an overview of the different CT systems and discus both theoretical and practical matters of CT imaging using the example of trabecular bone.  相似文献   
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