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We review evidence from human biology—paleopathological and isotopic paleodietary studies on ancient Maya skeletons—to assess the validity of ecological models of the Classic Maya collapse, in which elevated disease and deteriorating diet are commonly assumed. To be upheld, the health arguments of ecological models require that the Maya disease burden (1) was greater than that for many other societies and (2) increased over the span of occupation. The dietary argument requires (1) consistent change in diet from Preclassic and Early Classic Periods to the Terminal Classic and (2) increasing social divergence in diet. A correlation between diet and disease is necessary to link these arguments. Neither pathology nor isotopic data consistently support these criteria. Instead, it appears that local environmental and political factors created diversity in both disease burden and diet. In view of the human biological data, we are skeptical of ecological models as generalized explanations for the abandonment of Classic Maya sites in the southern lowlands.  相似文献   
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The original fineness of coins is very important information that can help us to understand the commercial situation in a wide historical context. This paper deals with a comparison of analytical methods suitable for the evaluation of the actual and original fineness of coins based on a detailed case study of a medieval coin sample. Both non‐destructive (i.e., scanning electron microscopy/energy‐dispersive X‐ray spectroscopy, X‐ray fluorescence, atomic force microscopy and hydrostatic weighing) and destructive (i.e., inductively coupled plasma – mass spectrometry and the Volhard titration method) techniques were used. The original fineness can be also deduced from knowledge of the internal structure of the coin (limited miscibility of copper and silver). A new analytical method based on a combination of a micrograph of the metallographic cross‐section with consequent image analysis was developed for determination of the original fineness. The proposed approach is relatively simple and provides reliable values. Sample heterogeneity and its impact on the determination of fineness are also discussed.  相似文献   
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The period comprising the end of the Early Neolithic and the Middle Neolithic, dated broadly within the fifth millennium cal BC, corresponds to an interval that remains largely unknown in the extreme north-western tip of Africa. This situation contrasts with that of the Early Neolithic, a period characterised by the earliest evidence of the diffusion of a productive economy, cultivated plants and domestic animals. The paucity of data for these later phases can be explained in part by the lack of secure contexts and sequences based on radiocarbon datings of short-lived samples. The current study presents the results of the excavations of El-Khil Caves B and C that yield materials allowing re-evaluation of the chronology of a type of ceramic known as Ashakar ware. The study also identifies two traditions in the northern Moroccan Middle Neolithic. The first is heir to the so-called Impressa Mediterranean ware and rooted in the Cardial Neolithic, while the second is characterised by roulette cord impressions, red slip and tunnel lugs and probably rooted in the region of the Sahara, and has no technological precedents in the study area.  相似文献   
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This paper aims to introduce a case study of Czechia in distribution of the EU funds and their spatial patterns. EU funds receive plenty attention from both European society and the scientific community. However, there is a lack of detailed evaluations of spatial and sectoral differentiation, which might bring a better understanding to the whole EU funds system. This paper attempts to fill this gap with a method of geographical differentiation analysis of the Czech operational programme Enterprise and Innovations 2007–15, which should increase the competitiveness of industry and develop services for commercial activities. Historically, subsidies often go to peripheral regions at the borderland with Slovakia and Poland, while regions along the borders with Germany and Austria receive only a low level of support. Jurisdictions of the major recipients from hi-tech sectors are mainly in the close vicinity of the largest cities (Praha, Brno), which are natural centres of high technologically demanding sectors, but a high share of high-tech subsidies goes to some peripheral districts as well. These findings can contribute not only to the academic discussion about contradictory developmental impacts of subsidies but to the all-European debate on the EU funds purposes as well.  相似文献   
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This paper introduces a special themed section that arose from an International Conference on Feminist Geographies and Intersectionality: Places, Identities and Knowledges, held in 2016 at the Universitat Autònoma de Barcelona. Six scholars of Canada, France, Greece, New Zealand, United Kingdom and United States seek to deal in five short papers with the intersectional dynamics of power structures and the central role of place within them. Here we situate the developments of intersectionality in feminist geographies in relation to the role of place and space in constituting intersectional relations, the relevance of context for the development of intersectionality and the use of different methodologies for research on it.  相似文献   
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