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991.
SEM–EDS, EMPA, ICP–MS and ICP–OES were applied to the study of three sectilia panels made of red, orange and yellow glass slabs. In order to determine the chemical state of Cu, XAS was also performed. The results indicate that, with the exception of the red samples, all slabs were made by mixing a siliceous sand with natron. The red slabs show significant compositional differences with respect to K2O and MgO contents, probably linked to the use of plant ashes as a source of alkali. The red, orange and yellow slabs are coloured by metallic copper, cuprite and Pb antimonates, respectively. The comparison between the chemical composition of the Faragola samples and several glass reference groups did not provide conclusive evidence of provenance.  相似文献   
992.
Attempts were made to detect ancient DNA (aDNA) in samples of 88 human skeletons from eight Neolithic and Bronze Age sites in Greece and Crete. Ancient DNA was absent in specimens from Nea Nikomedia, Lerna, Karaviádena (Zakro), Antron Grave Circle A and Mycenae Grave Circle A. For each of three skeletons from Antron Grave Circle B that were sampled, polymerase chain reactions (PCRs) gave products for nuclear but not mitochondrial DNA, but amplicon yield was low and inconsistent with replicate PCRs failing to give reproducible results. With specimens from Mycenae Grave Circle B, evidence for mitochondrial aDNA was obtained for four of the 22 skeletons that were studied, and at Kouphovouno evidence for mitochondrial and/or nuclear aDNA was obtained with eight of the 20 skeletons that were examined. We conclude that, although aDNA might be present in some Eastern Mediterranean skeletons from later centuries of the Bronze Age, it is not commonly found in material from this period and is likely to be absent from older material.  相似文献   
993.
994.
995.
Combining an analysis of the compliance incentives faced by firms in an emissions trading program, a comprehensive review of the enforcement strategies employed in Sulfur Dioxide Allowance and the Regional Clean Air Incentives Market (RECLAIM) programs, and a review of the compliance performance of these programs thus far, we are able to propose several practical guidelines for enforcing emissions trading programs. We stress the importance of prevailing market prices for emissions permits in determining compliance incentives, the importance of accurately measuring firms' emissions, and the importance of implementing enforcement strategies that remove the incentives firms may have to falsify emissions reports.  相似文献   
996.
997.
Law and legal discourses are an integral part of social life, a central means of producing social identities and exercising social power in day to day life. Critically informed geographical perspectives on law have illustrated in a number of ways how the legal and social (and therefore the spatial) are mutually constitutive. This paper argues that perspectives from critical legal geography can offer insights into the operation of asylum and immigration law in the UK in the late 1990s. This paper argues that legal practices and relations are organised in hegemonic and counter-hegemonic ways in different places and institutional contexts in London. In addition law and legal practices comprise a particularly important way in which ‘community’ can be constructed simultaneously across a variety of different scales in ways that can marginalise and exclude relatively powerless groups like asylum seekers. Thus refugee identities offer a particularly clear example of how social realities are constituted by law and legal practice.  相似文献   
998.
Ecological modernization theory posits that social movements play a central role in the environmental transformation of contemporary society. How they do so has received limited scholarly attention. This article seeks to reduce this thesis to a number of propositions which are then examined in light of the experience of the pulp and paper industry in the 1980s and 1990s. Drawing on field research and interviews in Southeast Asia, Australia and the United States, as well as available data, the study finds that social movements were instrumental in the environmental transformation of the pulp industry, with important differences between North and South. It concludes with a call for more nuanced studies of the influence of social movements on different sectors and countries, especially in newly industrializing countries where more tenuous and dependent forms of ecological modernization may be emerging.  相似文献   
999.
Recent work has celebrated the political potential of ‘counter‐mapping’, that is, mapping against dominant power structures, to further seemingly progressive goals. This article briefly reviews the counter‐mapping literature, and compares four counter‐mapping projects from Maasai areas in Tanzania to explore some potential pitfalls in such efforts. The cases, which involve community‐based initiatives led by a church‐based NGO, ecotourism companies, the Tanzanian National Parks Authority, and grassroots pastoralist rights advocacy groups, illustrate the broad range of activities grouped under the heading of counter‐mapping. They also present a series of political dilemmas that are typical of many counter‐mapping efforts: conflicts inherent in conservation efforts involving territorialization, privatization, integration and indigenization; problems associated with the theory and practice of ‘community‐level’ political engagement; the need to combine mapping efforts with broader legal and political strategies; and critical questions involving the agency of ‘external’ actors such as conservation and development donors, the state and private business interests.  相似文献   
1000.
The analysis by nuclear activation techniques and by inductively coupled plasma mass spectrometry combined with an UV laser of a large number of gold coins issued in the Arab Empire from the seventh to the 12th century ad showed that several different supplying sources were used, according to the region and to the period. The aim of this paper is to point out the circulation of gold in the Near and Middle Eastern mints of the Arab Empire and to make a parallel with the mints’ policies running in the other regions of the Empire, such as North Africa, the Iberian Peninsula and the Sicily. The identification of different gold ores by means of characteristic trace elements indicated recycling of the ancient coinage and, after ad 750, the minting in the entire Arab Empire of different new gold ores: Egyptian type, North Eastern type and West African type. The analysis of a small number of silver coins from the same periods and regions also showed a change in the ore supply after ad 750.  相似文献   
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