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31.
Lead isotope ratios of 15 Chinese bronze artifacts from the Yejiashan site (Suizhou City, Hubei Province) were analyzed and compared with copper ores across China. This study attempts to provide a new perspective to discuss the role that Zeng State played among all the vassal states in the early Zhou dynasty (ca. 1046–977 BC). The political presence of the Zhou dynasty in the middle Yangtze Plain is another main content of this paper. The lead isotopic characteristics of Chinese bronze artifacts between different historical periods are also in the scope of the study. By comparison, the lead isotopic ratios of the tested bronzes and copper deposits in the north Jiangxi Province show numerous overlaps. It indicates that the tested bronzes might have a single ore source, and this source was in the south of the Zhou dynasty. Combined with history and archaeological records, it is highly likely that the middle Yangtze Plain might be a part of the Zhou dynasty since the very beginning. Moreover, Zeng State might have a great influence in the ancient middle Yangtze Plain, and the nobles of Zeng State might even have authority to supervise certain area extending to Jiujiang. As lead isotopes of the bronzes appear to show a clear relation to chronology, the change of lead isotope patterns across times may further serve to distinguish the bronzes of the Western Zhou dynasty from the late Shang ones.  相似文献   
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Summary.  Despite the marginality of the region, the Later Bronze Age and Iron Age communities of the north-west of the Iberian Peninsula were engaged in active relationships with both Atlantic and Mediterranean peoples. Unlike other Atlantic regions, the area maintained direct contacts both with Mediterranean sailors and with the communities of the British Isles and north-western France simultaneously. The social relevance of these interactions and the range of imported goods transported varied throughout the first millennium BC. New evidence shows an intense involvement in Mediterranean trade from the fifth century BC onwards, while Atlantic contacts increased from the late second century BC, to reach a climax under Roman rule (first–second centuries AD).  相似文献   
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Here we show the results of two morpho-bathymetric surveys carried out on the underwater archaeological area of the Pozzuoli Bay (Naples, Italy). Such area is enclosed in the Campi Flegrei active volcanic complex, where bradyseism and recent volcanic activity strongly influenced the coastline shape over the last 2 Ka. The Digital Elevation Model (DTM) of the seafloor allowed to draw the main archaeological features of the Bay, that also include the military complex of Portus Iulius and the ancient thermal and villa complex of Baianus Lacus. The extraction of archaeological features from DTM was achieved thanks to the use of a GIS-derived tool based on the profile curvature algorithm. Thus, the Villa dei Pisoni (1st Century B.C.) and the thermal complex of Secca delle Fumose were investigated by using ultra-high resolution DTMs, that show the presence of Roman pilae for the protection of coastal buildings and also the inner planimetry of the Villa dei Pisoni complex. The observation of coastal engineering structures give also the opportunity to formulate some hypothesis on the evolution of morphology and of the sedimentary pattern of the area, while depth of archaeological remains allowed a rough computation of the rate of subsidence, resulted to be 2.55 (±0.5) mm/y for the Eastern sector (Pozzuoli) and 2.90 (±0.5) mm/y for the western (Baia).  相似文献   
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Clusters that emerged in the past have changed during the latest decades, so that today the research challenge in economic geography is on their evolution over time. The aim of this paper is to update the evolutionary path of SME Italian clusters, which faced the economic crisis are undergoing a process of decline in the number of firms. Furthermore, changes in the techno-economic landscape and in the competitive environment have generated new challenges. In this context, some leading firms, able to connect local resources (and firms) to global networks, have emerged over time and today they act as a gatekeeper. The focus will be on local networks interacting with leading firms and particular attention will be devoted to the pattern of co-evolution and to the geographical dimension of this co-evolutionary process. To empirically verify if other firms in the cluster may co-evolve with the leading firm over time, a deep analysis of the Gucci network in the leather products cluster in Florence will be carried out.  相似文献   
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In this study we applied a multidisciplinary approach, coupling geophysical and geochemical measurements, to unveil the provenance of 170 obsidian flakes, collected on the volcanic island of Ustica (Sicily). On this island there are some prehistoric settlements dated from the Neolithic to the Middle Bronze Age. Despite not having geological outcrops of obsidian rocks, the countryside of Ustica is rich in fragments of this volcanic glass, imported from other source areas. The study of obsidian findings was carried out first through visual observations and density measurements. At least two different obsidian families have been distinguished, probably imported from Lipari and Pantelleria islands. Analysing the magnetic properties of the samples, these two main sources were confirmed, but the possibility of other provenances was inferred. Finally, we characterized the geochemical signature of the Ustica obsidians by performing microchemical analyses through electron microprobe (EMPA) and laser ablation (LA–ICP–MS). The results were compared with literature data, confirming the presence of the Lipari and Pantelleria sources (Sicily) and indicating for the first time in this part of Italy a third provenance from Palmarola island (Latium). Our results shed new light on the commercial exchanges in the peri‐Tyrrhenian area during the prehistoric age.  相似文献   
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Brexit means that regions of the United Kingdom will lose access to the EU Cohesion Policy. Have EU funds been effective, and what might be the consequences of an interruption of EU financial support? This paper studies the impact of “Objective 1” funding—the highest form of EU aid—in Cornwall and South Yorkshire, two of the U.K.’s most subsidized regions. Counterfactual methodologies assessing their labor market and economic performance provide evidence of a positive effect of EU Objective 1 funds. When in 2006 South Yorkshire lost Objective 1 eligibility, this massively reduced its share of EU funds and the region was unable to sustain the gains obtained in previous years. This suggests that while Structural Funds may be effectively improving socio‐economic conditions of poorer regions, the performance of subsidized areas could be deeply affected by a reduction (or worse, an interruption) of EU aid.  相似文献   
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Italian district small and medium enterprises (SMEs) developed aggressive strategies to extend their sales networks and supply chains abroad. Literature on districts offered alternative explanations about the impacts of internationalization on local manufacturing systems. The authors consider the evolution of Italian districts in the framework of global value chain approach, focusing on the role of leading firms. Based on a survey of 650 Italian SMEs and financial indicators, the paper describes the rise of a new district firm model, the open network, which becomes a key node of global value chains. The paper also analyses the relationships among internationalization, innovation strategies and performance of SMEs.  相似文献   
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