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A longitudinal approach to migration behavior makes it possible to identify a sufficient condition for positive associations between rates of in-migration and rates of out-migration in the same regions. The longitudinal approach centers on the intervals of time that individuals spend in a region, and these intervals can be analyzed in terms of probability distributions or the equivalent hazard functions or survivor functions. Differences in the distributions of these intervals between subpopulations whose residence in a region begins with in-migration and subpopulations whose residence begins with other events are sufficient for temporal variations in rates of in-migration to produce variations in out-migration rates in subsequent periods of time. Tests for such differences are performed using data from the National Longitudinal Survey of Youth. 相似文献
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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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F. Albarde J. Blichert‐Toft F. de Callataÿ G. Davis P. Debernardi L. Gentelli H. Gitler F. Kemmers S. Klein C. Malod‐Dognin J. Milot P. Tlouk M. Vaxevanopoulos K. Westner 《Archaeometry》2021,63(1):142-155
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