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It is important to determine the geological sources of Palaeolithic ambers in the south of Europe in order to understand the mobility and interchanges of prehistoric societies. Fourier transform infrared (FTIR) spectroscopy analysis carried out on Upper Palaeolithic ambers from La Garma A cave (Cantabria, Northern Spain) allowed us to identify their source area. Their diagnostic features were found to be similar to the amber obtained in the Lower Cretaceous outcrops close to this archaeological site, and to differ clearly from Baltic amber, which has been generally suggested as the amber found in European prehistoric sites. These results show that the origin of the Gravettian amber found in La Garma A is local and, consequently, a hypothetical contact route is not required to be able to account for the presence of this material in the Iberian Palaeolithic context studied here. For the first time it has been demonstrated that the provenance of an archaeological amber in the Iberian Peninsula is local, with both geographical and spectroscopical evidences. Our study also concludes that the archaeological amber of La Garma A possibly belongs to an araucariacean resin that originated from the coniferous forests which grew in the northeast portion of the Iberian Plate c.110-million years ago.  相似文献   
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This article analyses the evolution of Community expenditure, on the basis of the data given in the budget and in the EDF, from the origin of the process in 1957 until the year 2002, the last definitive figures. The technique of principal component factor analysis has been applied to these variables. The basic objective of this study is to detect the interrelationships among the policies of the Union and to effect a classification of them, in order to detect the priorities of the European project and to estimate the dimension of the impact of its policies during the period.  相似文献   
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During every war between Denmark and Sweden from at least 1505 to 1676 popular peace treaties were concluded by common men on both sides of the national border. These treaties were negotiated in contrast to the aggressive policy of the political leaders and to the nationalistic discourse of the elite. The aim of this article is to use archaeology to give an economic, social, and mental background to these treaties, and to the regional identity across the border that they presuppose. Above all a specific building tradition seems to have given the peasants a mental affinity across the border.  相似文献   
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In this work, we present the results of the characterization of 20 lime plaster samples taken from the Sacred Precinct of Tenochtitlan (Mexico City), the ancient capital of the Aztec empire. The samples come from different buildings of this precinct (A, B and D) and from the west façade of phase VI of the Templo Mayor pyramid. The objective of the work is to characterize the plaster samples, to understand the raw materials used, and to evaluate the presence of similarities and differences among the samples in the building techniques and raw materials employed. All the samples were studied with OM, SEM–EDS and LA–ICP–MS. The study provided evidence of the plastering and replastering practice in the same constructive phases. The results of the analyses showed the existence of important similarities and differences among buildings and constructive phases in the Sacred Precinct. In order to understand the provenance of the limestone used in the plasters, the lumps and the binder of the samples were analysed. The results were compared with those of the limestone outcrops located in central Mexico. The provenance study showed that all the limestone used in the construction of the analysed buildings of Tenochtitlan's Sacred Precinct comes from the Tula region.  相似文献   
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This paper evaluates the impact of accessibility on the productivity of Spanish manufacturing firms. We suggest the use of accessibility indicators of workers and commodities, integrating transport, land use, and individual components, computing real distances or traveling times using the Spanish full road network. Estimated firms’ total factor productivity is explained as a function of the accessibility indicators and additional control variables. Results evidence the crucial role on firms’ productivity to the accessibility of commodities and to a slightly lesser extent the workers.  相似文献   
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In north-western Patagonia, obsidian was used during the entire Holocene, and its importance increased with time. Recent fieldwork discovered a new obsidian source located in the Río Grande, which was called ‘Coche Quemado' (CQ). The results indicate that the CQ source has a different geochemical signal than all other sources in the region. Its use is spatially restricted to piedmont and, to a lesser extent, the plains. Chronologically, CQ was exploited in the middle and late Holocene, and its use accounts for a range of spatial distribution between 150 and 200 km.  相似文献   
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20世纪50年代初期,以民族为名称的各层级自治区非均衡地建立,致使政府在已建立民族区域自治的地区与尚未建立区域自治的民族地区执行经济政策时出现偏差,经济政策偏差产生的优惠差异引发了都安瑶族群众谋求民族区域自治的问题。为了解决瑶族谋求民族区域自治问题,在采取经济政策调整和相应政治措施调整无果之后,为配合民族区域自治政策的落实,政府继而采取政区调整的方式,通过一系列行政区划调整的探索,最大限度地将瑶族纳入瑶族自治县内。最终,通过政区调整满足了少数民族对民族区域自治的需求,实现了民族地区各民族的和解与社会稳定。  相似文献   
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