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Many authors have considered pottery manufacturing constraints and sociocultural elements as factors in change in past civilizations over time. The main issue of this research is to better understand the reasons for changes, or choices, in pottery raw materials. The very precise and detailed stratigraphy and cultural succession of occupations is based on dendrochronological data from the lake‐dwelling sites of Chalain (Jura, France). Petrographic, palaeontological and chemical analyses were used to determine the nature and origins of the raw materials used by the Neolithic potters. Stratigraphy and dendrochronological data were used to reconstruct in detail the evolution dynamics of fabric changes. Several raw material sources were identified for many of the pottery groups. Each of them was sampled for qualitative experimental tests of pottery forming. The experimental results show a high variability between the sediments tested. This variability was quantitatively estimated by XRF, XRD, the Rietveld method, calcium carbonate quantification and laser grain‐size analyses of matrices, indirect measures of plasticity. These analytical results allow a better understanding of the differences observed in the experimental tests. On the basis of these experimental and analytical results, changing parameters such as pottery manufacturing constraints, mineralogical characteristics of raw materials and sociocultural factors are considered. In conclusion, all the social and technical parameters, in each archaeological context, must be taken into account for a better understanding of the changes occurring throughout the chronological sequence.  相似文献   
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A new accessible and easy method for studying past fire events using ‘dry sediments’ is presented. The method was developed for analysing samples from 17 locations in the Ambato Valley, NW Argentina, to study fire regimes in the area. Based on earlier researchers’ methods, guidelines to use microcharcoals in ‘dry’ sediments as a palaeoenvironmental proxy are provided. The procedures outlined include sampling/extraction in the field, preparations of the samples, laboratory analysis and quantification of the samples. The new approach was useful to meet the objectives and answer the questions initially proposed in our research about past fire regimes affecting the past Aguada society.  相似文献   
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In the beginning, Americans got it right. They did not fall for the false choice between the comfort of the least and the potential of the best, sometimes posed as a choice between the common good and individualism. Instead, the Founders envisioned a productive people who were at the same time a caring people. They identified social progress with realizing the potential of the best. More recently, social progress tends to be identified with the comfort of the least, which is a dumbing down of the idea of freedom.  相似文献   
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