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The aim of this proposal is to present an original approach to the study and preservation of rock art caves. A multidisciplinary study of cave wall alteration will be performed to understand the impact of environmental context on the evolution of wall surfaces. The approach involves the choice of a cave with characteristics similar to painted caves in the studied area (Vézère Valley in Dordogne, France): e.g., cave wall alteration, lithology, morphology, etc. This selected cave is intended to become a laboratory cave, monitored for the acquisition of chemical, physical and biological environmental data on bedrock, air and fluids along with their characteristics. A cave without art or archaeological interest has been chosen specifically to conduct experiments, to make in situ analysis and to obtain samples. The results are to be completed by specific observations in several other caves and compiled in a database.  相似文献   
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Archaeological practice within the European context of heritage management is facing huge challenges in ways of recording and reproduction of ex-situ preserved sites. As a consequence of the Valletta-treaty, numbers of archived images and drawings of excavated structures as prime sources of past human activity, are exponentially growing. Contrarily to portable remains however, their future study and revision is biased by the two-dimensional character of the recorded data, rendering difficult their future reconstruction for new study or public dissemination. A more realistic three-dimensional (3D) way of recording and archiving should be pursued. In this paper the possibilities for 3D registration of archaeological features are examined in a computer vision-based approach using the PhotoScan software package (Agisoft LCC). It proved to be a scientific and cost-effective improvement compared to traditional documentation methods. Advantages can be found in the high accuracy and straightforwardness of the methodology. The extraction of an orthophoto or a Digital Terrain Model from the 3D model makes it feasible to integrate detailed and accurate information into the digital archaeological excavation plan. The visual character of 3D surface modeling offers enhanced output-possibilities allowing a better documentation of in-situ structures for future research and a higher public participation and awareness for the archaeological heritage.  相似文献   
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In this paper, we use the funeral space and its liminal nature as a milieu for exploring how a ‘modern’ health intervention, the mosquito bednet, is negotiated by its recipients in relation to its (non)-usage in such spaces. With a focus on sleeping arrangements at funerals and drawing on empirical data from participants living in rural southern Tanzania, we discuss how the bednet is linked to the notion of being unsympathetic to the death. Viewed as a symbol of modernity and a reflection of wealth and individual pride, the bednet becomes physically and symbolically inappropriate in the more sacred, ‘in-between’ site of the funeral. We also uncover how risk perceptions regarding malaria transmission are re-cast in funeral spaces, with socio-cultural practices and health-related behaviours being simultaneously ‘risky’ for individual mourners and reinforcing in terms of group social cohesion. As individual mourners' concerns about malaria risks are suspended, notions of pain and discomfort come to the fore as part of the mourning process and respect for the deceased.  相似文献   
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The Palmottu hydrosystem is located in a granitic host rock in southern Finland. Along well‐defined pathways in the fractured crystalline rock, strontium isotopes are used to trace the degree of water–rock interaction (WRI) and mixing processes in groundwaters. The 87Sr/86Sr ratios range between 0.716910 and 0.735606 in the surface waters and between 0.719991 and 0.750787 in the groundwaters, but are between 0.720 and 0.735 in most of the samples. Moreover, the results show a lack of correlation between the water chemistries determining the classification into different water‐types (Na–Cl, Na–SO4, etc.) and the results of the strontium (Sr) contents and Sr isotopic ratios. From a WRI standpoint, this implies that the Sr behaviour is independent of the water chemistry; the occurrence of large 87Sr/86Sr variations is site specific and mainly dependent on the lithology. A model to determine the 87Sr/86Sr ratio of water after interaction with granite was developed. This model is based on the assumption that Sr was derived from three minerals: plagioclase, K‐feldspar and biotite. The results of the calculation indicate that around half of the water analysed within the Palmottu hydrosystem can be explained by the weathering of the granites. However, clearly lower 87Sr/86Sr are observed in waters when compared to the calculated 87Sr/86Sr and other sources of Sr, with low 87Sr/86Sr, rather than the calculated granite–water interaction, which may be suspected. When comparing the 87Sr/86Sr and ion ratios (Ca/Na, Mg/Na, Sr/Na, Cl/Na), the scattering of the data can be explained by the presence of four end‐members: a brine component (low 87Sr/86Sr and Ca/Na ratios…), a deep granitic component (high 87Sr/86Sr ratios and low Ca/Na ratios…), a subsurface component (intermediate 87Sr/86Sr ratios associated with high Ca/Na ratios…) and a surface end‐member:snow and river drainage (low 87Sr/86Sr and low Ca/Na ratios…). These extreme end‐members define a series of WRI‐mixing line within a rather complex hydrosystem.  相似文献   
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