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11.
The concentrations of two major elements and thirteen trace elements in 73 selected sherds of fine grey ware from the Iron Age and Roman period, excavated at Conimbriga, Santa Olaia and Tavarede, Portugal, were determined by instrumental neutron activation analysis. These concentrations were used to calculate distance matrices which were then subjected to cluster analysis employing SAHN and k-means methods, as well as to principal components analysis, to group the sherds according to the overall similarity of their compositional characteristics. The results showed that equivalent groupings appeared regardless of the taxonomic method used. Two major clusters were recognized corresponding to two different sites, namely Conimbriga and Santa Olaia, suggesting that the ceramics from these sites were made locally. No significant differences in compositional patterns were observed between iron age and roman sherds from Conimbriga.  相似文献   
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The pro‐life movement regularly employs tactics of political harassment in its campaign against abortion. As the murder of the controversial abortion doctor George Tiller in Wichita, Kansas, demonstrated last year, such tactics often betray a potential for violence. This paper explores how the militant tactics of the pro‐life movement in the 1990s have contributed to the formation of a ‘new’ political identity in Kansas politics: that of the moderate Republican. But for those that seek to counter‐mobilize against the Christian right, the political stakes remain high.  相似文献   
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A distinctive “Younger Fill” has been identified in the Mediterranean and adjacent regions. The dominant explanation for it is that of climatic change, first advanced by Vita-Finzi in 1960. Recent work on Greece by Bintliff appears to support the hypothesis. However, there are weaknesses. The present paper isolates the assumptions upon which the climatic hypothesis rests, particularly the notion of synchroneity and the apparent need for a universal mechanism. It sets out the grounds for scepticism, which include the ambiguity of the data, and attempts to evaluate the recent evidence from Greece. The paper then proceeds to argue that an anthropogenic origin cannot be ruled out and that it merits serious consideration. Criteria are suggested which the reinstated explanation would need to meet.  相似文献   
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