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In order to carry out strontium (Sr) isotope analysis, glass artefacts from South Asia were sampled with portable laser ablation (pLA), a relatively novel sampling technique that leaves damage invisible to the naked eye. Subsequently, thermal ionization mass spectrometry (TIMS) was used to obtain Sr isotope ratios after sample dissolution and separation. In this study, the goal was twofold: to determine whether the measurements of Sr isotope ratios were impacted by using a portable laser as a sample tool; and to assess the pertinence of using Sr isotope ratios to provenance Indian glass. Despite a deterioration in the precision of the measurement of the Sr isotope ratios for artefacts sampled with pLA compared with the traditional sampling method, the Sr isotope ratios of certain Indian glass are so different that this does not affect their separation but a comparison of data sets obtained using standard methods and pLA might be challenging.  相似文献   
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The reasons why the Western Mediterranean, especially Carthage and Rome, resisted monetization relative to the Eastern Mediterranean are still unclear. We address this question by combining lead (Pb) and silver (Ag) isotope abundances in silver coinage from the Aegean, Magna Graecia, Carthage and Roman Republic. The clear relationships observed between 109Ag/107Ag and 208Pb/206Pb reflect the mixing of silver ores or silver objects with Pb metal used for cupellation. The combined analysis of Ag and Pb isotopes reveals important information about the technology of smelting. The Greek world extracted Ag and Pb from associated ores, whereas, on the Iberian Peninsula, Carthaginians and Republican‐era Romans applied Phoenician cupellation techniques and added exotic Pb to Pb‐poor Ag ores. Massive Ag recupellation is observed in Rome during the Second Punic War. After defeating the Carthaginians and the Macedonians in the late second century bce , the Romans brought together the efficient, millennium‐old techniques of silver extraction of the Phoenicians, who considered this metal a simple commodity, with the monetization of the economy introduced by the Greeks.  相似文献   
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Emerging debates on the contemporary reconfigurations of work question previous understandings of the relationships among and between waged, unwaged, and reproductive labour, situated processes of value formation and/or enclosure, and the constitution and limits of contemporary capitalism. Taking Cindi Katz's notion of countertopographies and Gillian Hart's notion of relational comparison as inspirations, this Symposium draws attention to new and existing conceptual frames and modes of analysis to situate contemporary permutations of work within the shifting dynamics of uneven development in specific state, local, and institutional contexts. This Introduction summarises the interrelated and overlapping contributions that papers in this Symposium offer methodologically, analytically, and politically. The open-ended aspiration that emerges from these contributions is that close attention to heterogeneous formations of work outside the wage might help to multiply forms of vigilance and critical praxis necessary to resist the co-optation and enclosure of people's creative energies, and move toward realising the latent liberatory potentials that several of the contributions suggest.  相似文献   
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Limestone from quarries known to medieval craftsmen and from the monuments they built and embellished, as well as from carvings now in museum collections, has been characterized by neutron activation analysis. Specimens from 38 quarries in the Lutetian and Jurassic limestone formations of France and from sculptures in American and French museums have been tested, and the results have been compiled in a data base to which art historians may refer when attempting to determine provenance for sculptures. Multivariate statistical analysis of concentration data shows stone from a particular quarry in the Paris basin to be compositionally homogeneous and distinguishable from other quarries in the same formation. The same approach to data related to quarries near the Burgundian abbey of Cluny finds general agreement between classifications based on compositional and on petrographic data, but the number of samples available for analysis at the time of writing was insufficient to achieve the finer distinctions reported for the Paris basin.  相似文献   
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This paper introduces a pattern recognizer, similar to weighting schemes used in combining time series forecasts, for use in spatial adaptive filtering applied to estimating multivariate cross-sectional models. The pattern recognizer enhances the ability to automatically detect and estimate parameters with discontinuous or sharp gradient changes over geographic contexts. Results from Monte Carlo studies suggest that the weighted spatial adaptive filter is at least as accurate as the unweighted filter for cases having smoothly changing parameters, but superior for cases having discontinuous, step-jump parameters. A case study on illicit drug-market activities using census tract-level data from Pittsburgh, Pennsylvania, further illustrates the advantages of the weighted filter.  相似文献   
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Current federal hazardous and low-level radioactive waste management policies (under conjoint federalism) fail to balance national concerns for consistency with state concerns for equity, discretion, and adequate resources. Congress should expand conjoint federalism to permit states to charge differential fees on imported hazardous waste as it does for low-level radioactive waste. For low-level radioactive waste, clarification of the "take title" issue makes the present framework for state discretion implementable, given sufficient time.  相似文献   
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