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151.
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The first part of this paper is a brief critical history of the use of Pb isotopes for inferring the geological provenance of archaeological materials, with an emphasis on non-ferrous metals. The second part examines variation in the Pb isotopic ratios of oxide and sulphide ore minerals in selected regions of the world, and relates these to the geological histories of ore formation in each region. This exercise shows that in regions where most ore deposits are of similar geological age—as in the Andes, Europe and the circum-Mediterranean—provenance analysis with Pb isotopes is inherently difficult because geographically distant sources often exhibit similar isotopic ratios. Conversely, regions with many periods of ore formation—such as southern Africa—appear to be very promising regions for future studies of provenance with Pb isotopes. The wider implication of this exploratory survey is that archaeologists should carefully consider the range and clustering of geological Pb isotopic ratios in their regions of interest before investing large sums of money into Pb isotopic analysis of artefacts.  相似文献   
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The study analyses the chemical composition of 57 glass samples from 40 beads discovered at 20 archaeological sites in Poland. The beads are dated to Hallstatt C–Early La Tène periods (c.800/750–260/250 bce ). Analyses were carried out using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Two groups were distinguished among the glasses based on the MgO/K2O ratio: high-magnesium glass (HMG), five samples; and low-magnesium glass (LMG), 52 samples. The former were melted with halophyte plant ash, the second with mineral soda. These glasses were produced in the Eastern Mediterranean (more likely in Mesopotamia or Syro-Palestine than in Egypt) and transported in the form of semi-products to secondary glass workshops in Europe. Some of the white opaque glass was coloured and opacified in Europe.  相似文献   
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Nearly 40% of agricultural workers in the United States earn an hourly wage that is within 10% of the prevailing state-level minimum wage. We evaluate the impact of the minimum wage on farm employment using county-level data from the United States Census of Agriculture. We employ long-differences specifications and find evidence of a dynamic, negative effect of the minimum wage on seasonal agricultural employment, but no effect on year-round agricultural employment. We estimate a long-run elasticity of total agricultural employment with respect to the minimum wage of about −0.40, which is both statistically and economically significant. Employers’ total expenditures on hired agricultural workers are not affected by the minimum wage. Finally, our analysis suggests that increases in minimum wages may lead to higher capital investment as well as the consolidation of farming operations in the agricultural sector.  相似文献   
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ABSTRACT

This article analyses regional agency in the early phases of new path constitution. We argue that the early stages of new path constitution can be explained by both structural factors and the strong presence of agency. With a specific focus on agency, this article contributes to the literature by providing a study of the role of agency at different stages of path constitution. The study shows that two types of agency operate together. Public policy agency is carried out through a common thrust for policy tools that can enhance the room to manoeuvre together. In addition, strong entrepreneurial agency functions as a locomotive for other firms which are important trigger points, and pushes the process forward. These two forms of agency need to be interrelated to constitute new paths.  相似文献   
158.
When people first inhabited the Remote Oceanic region of the world at 1500 b.c., they generated archaeological sites attesting to their practical coastal adaptations in tandem with their ceremonial traditions, wherein water figured vitally in daily living and ritual performance. Of eight known first-settlement sites in the Mariana Islands, Ritidian in Guam uniquely incorporates one residential habitation plus two caves related to water collection, pictographs, consumption of unusual foods, and use of exceptionally decorative objects. The inter-connected findings clarify what was “special” about the special-use caves, in total articulating a fuller sense of cultural life and landscape than otherwise could be possible.  相似文献   
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Five Iron Age ceramic lamps from a tomb at the site of Sahab in the south‐eastern part of central Jordan were analysed using gas chromatography – mass spectrometry (GC–MS). The results of this study provide data on the type of fuel used in three of these lamps. The study proposes that animal fat, possibly of ruminant origin, was used in three Early Iron Age II lamps. The material used in the other two Iron Age I lamps could not be determined due to the absence of diagnostic biomarkers. The data obtained from the lamps can be put in conjunction with the archaeological evidence on the availability of domestic animals and, most probably, use of their products at the site of Sahab during the Iron Age.  相似文献   
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The cemetery of Le Morne in Mauritius dates from the 1830s and is thought to contain the remains of slaves, freed slaves or potentially free Madagascans, which in itself has economic and social implications and makes the cemetery all the more intriguing. During 2010, excavations recovered the remains of 11 individuals, of which six were children. Although a small sample, the burials of the non‐adults show several interesting features. Two neonates were buried contemporaneously and may have been twins, while a late term foetus in a grave with a young woman may represent an incident of coffin birth. This sample has the potential to cast light on the burial practices of the slave/ex‐slave community in Mauritius, about which little is currently known. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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