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1.
New work at Kehf el Hammar Cave provides the first well-dated palaeoenvironmental sequence for the Late Upper Palaeolithic in this region of the northwest Maghreb. The archaeological layers are dated via a combination of AMS radiocarbon and luminescence dating methods. The sequence contains charcoal-rich occupation layers with faunal, human and lithic finds. Local vegetational patterns are reconstructed on the basis of preliminary analysis of the charcoal evidence. Using standard calibration curves the AMS radiocarbon dates are compared with proxy evidence for climatic change from sea core records in the Alborán Sea. These appear to show that the Late Upper Palaeolithic occupation of the region coincides closely with Heinrich Event 1, a period marked by intense aridification and dating to ca. 16,700–17,250 calendar years ago.Les nouvelles recherches dans la grotte de Kehf el Hammar ont permis d’obtenir la première séquence paléoenevironnementale bien datée du Paléolithique supérieur tardif au Nord Ouest du Maghreb. En effet, les niveaux archéologiques ont été datés par le radiocarbone par accélérateur (AMS) et des méthodes radiométriques basées sur la luminescence. En revanche, les paléoenvironnements végétaux ont été partiellement reconstitués à base des premières analyses des charbons de bois. Les dates AMS calibrées ont été comparées aux données climatiques issues des carottes marines dans la mer Alborán. Ainsi, les occupations humaines du Paléolithique supérieur tardif dans la région ont sensiblement coïncidé avec l’événement climatique Heinrich 1. Celui-ci correspond à une période qui a été marquée par une aridification intense entre 16.700 et 17.250 ans (cal.).  相似文献   
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Richards et al. (2000) reconstructed the diet of the human remains found in Gough's and Sun Hole Cave through isotope analysis. They concluded that these people consumed an entirely terrestrial-based diet. Their reconstruction was based upon comparison of the results from human bones with those from a very small number of associated animals. The diets of the Gough's and Sun Hole Cave human were different from the other six Upper Palaeolithic humans from the British Isles for which dietary information has been obtained through isotope analysis. The work of Richards et al. (2000) suggests that they were the only ones for whom marine or freshwater resources did not play a significant role in their diets. We test this through further analyses of faunal remains from Gough's Cave, Sun Hole and other contemporary sites (Kent's Cavern, Aveline's Hole, Kendrick's Cave). Despite the limited faunal sample, the original palaeodietary reconstruction is broadly consistent with our findings. The isotope values of the main protein sources consumed by the humans from both sites are consistent with those of red deer and bovines, and, for a single individual, with that of horse and red deer. Reindeer was postulated in the original reconstruction as a potential food source, but this seems very unlikely based on our isotope reconstruction and the archaeological remains.  相似文献   
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Some radiocarbon dates for ancient Egypt have been significantly offset from the established historical chronology (see Bonani et al., 2001). In this paper, short-lived plant species collected in Egypt between 1700 and 1900 AD were used to investigate the possibility that the radiocarbon record had been influenced by reservoir effects. AMS radiocarbon measurements were made on 66 known-age samples, resulting in an average offset from expected values of 19 years. The implications of this minor discrepancy on the likelihood of a reservoir process are discussed, and the agreement of the data with recent models of radiocarbon seasonality is also considered.  相似文献   
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The Palace of Westminster is in need of urgent, substantial repairs. This provides a ‘window of opportunity’ for change. This essay traces the restoration and transformation (or lack of) that the Palace of Westminster has seen in the last half a century, before assessing its current state, and considering whether parliament is fit for purpose. It provides a ‘long‐view’ understanding of previous missed ‘windows of opportunity’. The essay focuses on drawing insights from history in order to add a depth of understanding to the contemporary issue. An understanding of the preceding renewal and restoration projects enables us, potentially, to avoid some of the problems that have been previously experienced, and finally seize this opportunity to build a parliament which is fit for purpose.  相似文献   
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FLAX-RETTING POOLS, hitherto unrecognized, still survive in the landscape of NW. England, in close association with fulling-mill sites, tenter banks and simple potash pits. The retting-pool sites have common characteristics—usually on flat land; close to a river, but utilizing small streams which have been channelled to provide a controlled water supply; and raised banks for the drying of the retted flax. The field evidence occurs in documented contexts which show that a widespread linen industry was contemporary with, and often linked to, the 12th- and 13th-century demesne woollen industry.  相似文献   
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