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181.
The ability to make rapid measurements on small samples using laser fluorination enhances the potential of oxygen isotopes in the investigation of early inorganic materials and technologies. δ18O and 87Sr/86Sr values are presented for glass from two primary production sites, four secondary production sites and a consumer site in the Near East, dating from Late Antiquity to the medieval period. δ18O is in general slightly less effective than 87Sr/86Sr in discriminating between sources, as the spread of measured values from a single source is somewhat broader relative to the available range. However, while 87Sr/86Sr is derived predominantly from either the lime‐bearing fraction of the glass‐making sand or the plant ash used as a source of alkali, δ18O derives mainly from the silica. Thus the two measurements can provide complementary information. A comparison of δ18O for late Roman – Islamic glasses made on the coast of Syria–Palestine with those of previously analysed glasses from Roman Europe suggests that the European glasses are relatively enriched in 18O. This appears to contradict the view that most Roman glass was made using Levantine sand and possible interpretations are discussed. 相似文献
182.
A recent analytical study by SEM–WDS was carried out on 226 glasses from the Late Bronze Age, analysing each of the glasses for a total of at least 22 elements, the largest such analytical study conducted on these glasses. The aim of the analysis was first to identify which elements were brought in with each of the raw materials and, second, to accurately characterize those raw materials. Since different glassmaking sites in Egypt and the Near East would probably use at least some local raw materials and these raw materials will vary slightly from site to site, this has potential for provenancing the glass. Analysis showed new patterns in the compositions of glass from the various sites and led to new conclusions about the supply of raw materials and personnel for the glass workshops. This forms the basis for further work by LA–ICPMS to be presented in part 2 of this paper. 相似文献
183.
Laguna Guatavita, a crater‐like lake located in central Colombia, was used by pre‐Columbian Muisca people for a variety of socio‐religious ceremonies, many of which involved casting offerings into the lake. Of these, the installation of a new ‘king’ became the basis of the El Dorado myth that was carried back to Europe by 16th century conquistadores. In the present study, beads collected from Laguna Guatavita during a late 19th/early 20th century attempt to recover valuables from the lake bed, have been subjected to geochemical analysis. Results establish that these artefacts have been fabricated from Class Ib amber. Class Ib ambers have not previously been reported in either the geological or archaeological records of Central or South America, and their existence in this context implies that the Muisca people had access to a unique local or regional source of amber, knowledge of which has subsequently been lost. 相似文献
184.
Jan K. Brueckner 《Journal of regional science》2006,46(5):847-865
ABSTRACT This paper develops a model of social networks different from those presented in the recent literature. In contrast to existing models, the level of investment in link formation is a continuous decision variable, and links form stochastically rather than deterministically, with the probability depending on the noncooperative investment choices of both parties. Since the network structure is then stochastic rather than deterministic, the actual pattern of links cannot be specified, as in previous models, with the analysis focusing instead on which links are most likely to form. This alternate approach leads to a much simpler mathematical structure than in previous work. The analysis, which is couched in the context of friendship networks, shows that individual investment in friendship formation is too low. In addition, the analysis shows that, in an asymmetric setting where one individual has personal magnetism or a broad group of acquaintances, friendship links involving this attractive agent are most likely to form. 相似文献
185.
Changing patterns of carnivore modification in a landscape bone assemblage, Amboseli Park, Kenya 总被引:2,自引:1,他引:1
This study compares the landscape-scale taphonomic signal of carnivore modification to the surficial bone assemblage in Amboseli Park, Kenya as it was in 1975 and 2002–2004. Change in predator abundances over time provides a means of assessing the taphonomic signal of carnivore-mediated bone consumption and destruction under differing ecological conditions and varying levels of conspecific competition for resources. The landscape assemblage indicates taxonomic variation in the patterning of carnivore modification to ungulates of different size classes as well as within equivalent size classes. Analyses of long bone elements indicate that the differential destruction of limb ends and the strength of the correlation between limb end abundance and bone mineral density provide an indication of the intensity of carnivore modification to a faunal assemblage. The ability to infer levels of carnivore modification based on limb elements can provide faunal analysts with the tools to determine whether the taphonomic signals in the fossil record relate to carnivore modification, hominin transport of appendicular elements, or both. 相似文献
186.
This essay seeks to broaden the empirical basis for the concept of spatial discipline by investigating how and why the geographical mobility of skilled iron workers was constrained in the United States during the decades preceding the Civil War. Drawing on neo-Marxist labor theory, the author finds that the paradoxical demands of industrial capitalism for a highly mobile labor force that would also stay in place created particularly acute tensions in the iron industry, where skilled labor was critical to the implementation of new technologies. Recent theoretical developments in legal and labor history help explain why the transition from master-and-servant relations to employment at will in the early nineteenth century heightened tensions in the iron industry and spawned a tremendous range of disciplinary strategies. After modeling managerial strategies as a continuum of coercion, the author presents a series of illustrative examples from the North and South. 相似文献
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