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Due to the construction of a new North-South subway in Cologne, Roman time harbour sediments were exposed and were sampled for luminescence dating. A very good independent age control was given by the precise knowledge of the chronology of Roman activity and by radiocarbon ages of charcoal samples. Hence, different methodological approaches within luminescence dating were applied for Holocene heterogeneously bleached fluvial samples and were compared to the known ages. For one sample, optically stimulated luminescence (OSL) dating was applied to coarse-grained quartz using a single aliquot regenerative-dose (SAR) protocol. After De-measurements, different statistical approaches were tested (i.e. arithmetic mean, median, minimum age model, finite mixture model, leading edge method and the Fuchs and Lang approach). It is demonstrated that the Fuchs and Lang approach along with the leading edge method yielded the best matching OSL ages with respect to the known ages.  相似文献   
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The appearance of rich and diverse funerary practices is one of the hallmarks of the Late Epipalaeolithic Natufian in the Levant. Numerous burials at a number of sites excavated mostly in the Mediterranean zone of the southern Levant have fed into the interpretation of the Natufian as a sedentary society of complex hunter-gatherers. Here, we report on the human remains recovered from Shubayqa 1, a well-dated early to late Natufian site in northeast Jordan. The majority of the minimum of 23 individuals that are represented are perinates and infants, which represents an atypical population profile. Ground stone artifacts and traces of colorants are associated with some of these individuals, providing a rare insight into funerary treatment of subadults in Natufian contexts. We interpret the Shubayqa 1 evidence in the light of current and ongoing debates concerning Natufian burial practices and the issue of social complexity.  相似文献   
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In one of the first quantitative designs, we explore the impact of both legalisation and flexibility on regime effectiveness, using data on international environmental institutions. One of the main implications is that ‘precision’ is an important determinant of regime performance. If the rule and norm system is well defined, well understood and clear, then a regime tends to be more effective in addressing an environmental problem. We do not find evidence, however, that ‘hard law’ is more effective than ‘soft law’ or that delegation mechanisms may be relevant. Second, flexibility in the regime structure increases regime performance – regular instead of subsidiary bodies enhance flexibility and thus have a positive effect on a regime's environmental problem management. Flexibility in states' agenda setting power, membership and decision making do not seem to have a crucial influence, though.  相似文献   
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In the last few decades optically stimulated luminescence (OSL) dating has become an important tool in geochronological studies. The great advantage of the method, i.e. dating the depositional age of sediments directly, can be impaired by incomplete bleaching of grains. This can result in a scattered distribution of equivalent doses (DE), leading to incorrect estimation of the depositional age. Thoroughly tested protocols as well as good data analysis with adequate statistical methods are important to overcome this problem. In this study, samples from young fluvial sand and flood plain deposits from the Elbe River in northern Germany were investigated to compare its depositional ages from different age models with well-known historical dates. Coarse grain quartz (100–200 μm and 150–250 μm) and polymineral fine grains (4–11 μm) were dated using the single aliquot regenerative (SAR) dose protocol. The paleodose (DP) was calculated from the DE data set using different approaches. Results were compared with the development of the Elbe River, which is well-documented by historical records and maps covering the last 1,000 years. Depending on the statistical approach it can be demonstrated that depositional ages significantly differ from the most likely depositional age. For the investigated coarse grain quartz samples all ages calculated from the MAM-3UL, including their uncertainties, are within the historical documented age. Results of the polymineral fine grain samples are overestimating the historically documented depositional age, indicating undetectable incomplete bleaching. This study shows the importance of using an adequate statistical approach to calculate reliable OSL ages from fluvial sediments.  相似文献   
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This article provides a study of political positions concerning the role of religion in modern society in Sweden between 1920 and 1939. It aims to increase understanding of the Swedish secularization path, with special emphasis on issues related to heritage and national identity, by comparing the dominant perspectives on these issues in the Church of Sweden and in the Social Democratic Party during that period. It addresses how these positions have influenced policies during the period, as well as some of their implications for later path dependence. It explores relations between religious issues and the concept of national heritage, as well as how the fact that both were at that time commonly seen as legitimate tasks of the state came to influence the development of Swedish church-and-state relations and heritage policies. Special attention is given to the positions of the Young Church Movement, a movement within the Church emphasizing its role as a national church with a central position in national identity, as well as to the views of Arthur Engberg, the anti-clerical Social Democratic government minister responsible for church, education, and culture in the 1930s.  相似文献   
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