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Arsenic has previously been measured in a bone sample of a c. 5-year-old Mesolithic child from Nivaagaard in Denmark yielding an anomalously high value of 13 μg/g. In the present work we show that other individuals at a nearby site also exhibit elevated arsenic levels, whereas individuals from other Mesolithic sites in Denmark are found to have quite low As-concentrations. Several attempts to reveal the source of the arsenic are reported: A railway track near the site, where the railway sleepers were suspected to have been impregnated with As leading to transport or diffusion of As into the adjacent soil; Several food items, the remains of which were found at the site, and one food item not preserved in the excavation, i.e. seaweed. Finally, it is shown that the most likely explanation of the elevated arsenic levels in human bones at Nivaa is diagenesis.  相似文献   
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The article presents the results of a study based on activity analysis of a medieval churchyard of St. Clemens in the urban setting of Copenhagen. The churchyard was in function from the 11th to 16th century revealing changes in layout and burial rites over time. A glimpse of the symbolic life of the medieval Copenhageners is also exposed and analysed. Moreover, the study of the churchyard reveals activities of a more secular nature and presents some of the activities that must have been part of everyday life in the medieval town. Thus, the churchyard has not only been an arena for meetings between the living and the dead but also a location for experiencing the urban life burgeoning outside the churchyard. For comparison, a recently discovered contemporaneous churchyard at Rådhuspladsen is also discussed.  相似文献   
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This article aims at gaining greater insight into the functioning of small-scale industries in an African context. The findings are based on predominately qualitative fieldwork conducted on small-scale carpentry industries in Accra, Ghana. A special concern is whether the small-scale carpenters are capable of acquiring the technological capabilities conducive to a positive industrial development. Two opposing frameworks, one neo-Marxist and one centred on the conceptualisation of industrial districts, are used to discern the nature of locally embedded production and supply linkages, and whether these are conducive to the technological capabilities needed for innovative growth. Despite facing similar structural constraints there are a few small-scale enterprises that remove themselves from the characteristics of informal production by making the greatest use of the services entailed in the carpentry production network. These linkages, however, are still not extensive enough, nor advanced enough, to bring about the technological innovations associated with a true industrial district. The benefits gained through interlinked production are thus better understood as a means of securing domestic resilience, rather than international competitiveness. Furthermore, an explanation for the limitations of these linkages must be sought beyond the meso-level analysis typical of an industrial district approach.  相似文献   
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