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Thermoluminescence dating of heated flint artefacts from the Middle Palaeolithic sequence of Chez-Pinaud Jonzac (France) places an assemblage of Quina type Mousterian into MIS 4, while the overlying assemblage of Denticulate Mousterian which is followed by two layers with Mousterian of Acheulean Tradition are all assigned to MIS 3. TL dating is used to verify the mixed nature of deposits from which diagnostic Middle as well as Upper Palaeolithic tools were recovered. The TL ages are significantly different for samples from this layer and broadly agree with the archaeological attributions. While the study is generally limited by the low number of heated samples available, a correlation with a generalized chronostratigraphic sequence is possible by including proxy data from the faunal remains associated with the lithic assemblages in question. The Quina Mousterian in southwestern France, therefore, can be placed by chronometric dating methods in MIS 4 to MIS 3.  相似文献   
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If the overall expansion of the farming system was determined by the Neolithic Demographic Transition (NDT), i.e. by demographic pressure, what determined the rate of expansion? What is the link between the rate of expansion, the farming system and demographic density? In a first approach, the issue of the different rates of expansion of the farming system on the map is addressed in terms of 21 geo-ecological, climatic and cultural factors and forager populations, via an ordinary least square regression technique (OLS). In a second approach, the variability of the rate of expansion is analyzed in terms of specific patterns identified for the ceramic culture areas, via a cluster analysis. The expansion rate is negatively correlated with the intensification of the agricultural system, as well as with demographic density. Expansion is slow in ecosystems with an intensive farming system with relatively high demographic density, and vice-versa.  相似文献   
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L'auteur montre que contrairement aux études dans ce domaine la dureté totale de l'eau potable ne semble pas influencer la mortalité ischémique du cœeur. Cette relation est examinée selon que la localisation géographique des municipalités des Cantons de l'Est ob-servées se trouve sur un gîte calcaire, selon l'origine de I'approvisionnement en eau potable. Les résultats montrent que les composantes physico-chimiques telles que le calcium et le magnésium peuvent dans des cas précis étre déterminants. L'emploi de données socio-économiques (l'âge du logement, le revenu, par exemple) apparaît plus probant.
Contrary to the results of other studies, the total hardness of drinking water does not seem to influence the death rate from ischaemic heart trouble in the Eastern Townships. This conclusion is based on an analysis of mortality rates in relation to the origin of domestic water supplies and location on sources of calcium. Although the results show that the physico-chemical components, such as calcium or magnesium, can be determined in certain cases, socio-economic variables, such as housing age or income, seem more significant.  相似文献   
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Today, exactly 500 years after the discovery of America, there is still a lot of controversy about the history of syphilis in Europe, especially about the Columbian and pre-Columbian hypotheses. This paper presents evidence for the presence of venereal treponematosis in the late Antiquity in France. The case that we examined comes from the necropolis of Costebelle (3rd-5th centuries AD; Hyères, Var, France). Grave no. 1 contained the well-preserved skeleton of a relatively old woman with the skeletal remains of an approximately 7-month-old fetus in her pelvic cavity. The osseous lesions of the fetal remains can be described in four groups: periosteal appositions on the skull vault (frontal and parietal); signs of periostitis on the long bones (bilateral cortical irregularities, predominantly on the left side, which affect first of all tibiae, femora, fibulae, radii and humeri, particularly in the metaphyseal region); some infraperiosteal detachment reminiscent of an infraperiosteal haematoma surrounding the distal extremity of the left forearm and the left hand; and finally, the irregular lesions of the humeral distal and proximal tibial metaphyses reminded us radiologically of Wimberger's signs. The most probable diagnosis of all the lesions mentioned above is that of a precocious congenital syphilis. This case consists of an argument against the epidemiological theories about the migration of Treponema pallidum from the New World back to the Old World starting at the end of the 15th century.  相似文献   
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Radiogenic lead and strontium isotope data are presented for lead‐ and calcium carbonate/barium sulphate‐containing paint and ground samples from 15 paintings, executed between 1844 and 1871, by 19th‐century Canadian artist Cornelius Krieghoff. Like many artists of this era, Krieghoff used lead‐based pigments such as lead white, chrome yellow and Naples yellow, and extenders such as calcium carbonate and barium sulphate. The lead isotope analyses of the majority of these pigments are consistent with the isotopic compositions of lead mined from European lead deposits in England and/or Germany. However, three samples from Krieghoff's early career yield lead isotope compositions that are much more radiogenic than European sources. The lead isotope compositions of these three samples are consistent with the addition of a more radiogenic lead component that is similar to the lead derived from North American lead deposits in Missouri and Illinois (Mississippi Valley Pb–Zn type deposits). The strontium isotope compositions of the extenders suggest that the raw materials for calcium carbonate or barium sulphate extenders were largely derived from Palaeozoic to modern‐day marine environments. This study shows that pigments manufactured from North American lead were being incorporated into Canadian paintings as early as 1844.  相似文献   
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