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Olaf Nehlich Janet Montgomery Jane Evans Sabine Schade-Lindig Sandra L. Pichler Mike P. Richards Kurt W. Alt 《Journal of archaeological science》2009
A combination of stable carbon and nitrogen isotope analysis of collagen and radiogenic strontium isotope analysis of tooth enamel was used to investigate diet and mobility at the early Neolithic settlement of Nieder-Mörlen in Germany. The carbon and nitrogen ratios suggest a mixed terrestrial based diet that is consistent with data previously published for early Neolithic sites in Europe. The strontium isotope data indicate a high degree of human mobility with only one individual having an isotope ratio consistent with locally derived strontium. Unusually, a group of non-local juveniles with isotope ratios typical of upland regions is also present at the settlement but there are no adult burials with such values. Whilst transhumance is considered as an explanation, it would not explain why these non-local juveniles lived foreshortened lives and other possible mechanisms are therefore discussed. 相似文献
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We review the existing data sets for the production and consumption of copper-base objects at Indus sites, outline a working
typology for metal objects, and provide new data from on-going analytical work on the copper assemblage from Harappa. The
role of metals in the economic and social networks of the Indus tradition is examined in terms of patterns of use and technological
style. We note that Indus metalsmiths apparently relied more on procurement of metal ingots or scrap than on primary ingot
production through smelting, which would have affected other aspects of Indus metallurgy. Object production did not involve
elaborate forms, but may have involved complex alloying. Finally, we conclude that there is no evidence for elite control
of metal production, and that access to metals was relatively widespread. 相似文献
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Kurt Van Dender 《Journal of regional science》2005,45(2):343-362
Abstract. Consider two firms, at different locations, supplying a homogenous good at constant marginal production cost. Consumers incur travel costs to the firm for each unit purchased, and the travel costs increase with the amount of travel to each firm (congestion). When all traffic and all congestion are generated by travel to a duopolist, both the Nash–Bertrand equilibrium prices and the Nash–Cournot equilibrium prices exceed the sum of the marginal production cost and the marginal external travel cost. However, when the road is shared by travelers to the duopolists' facilities and travelers in competitive markets, the Nash–Bertrand duopoly price equals the competitive price and the Nash–Cournot price contains a markup. 相似文献