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H. I. Hollund N. Arts M. M. E. Jans H. Kars 《International Journal of Osteoarchaeology》2015,25(6):901-911
Teeth are often the preferred source material for isotopic and genetic assay involving ancient biomolecules. The assumption is that dental tissue preserves better due to its anatomically protected location, the enamel cap, and lower porosity compared to bone. However, this assumption has not been widely tested. Some similarities in diagenetic processes are to be expected due to similarities in structure and chemical composition of dentine and bone. This has led to the suggestion that bone can be used as an indicator of dental preservation, as a pre‐screening technique in the selection of suitable samples for biomolecular studies. Thus, direct testing of the correlation between bone and tooth preservation and diagenesis is needed. This paper reports the results of the histological characterization of diagenetic alterations within 25 human femur–tooth pairs, from a Medieval to modern (AD 1850) cemetery in Eindhoven, the Netherlands. The results showed that teeth do indeed preserve better overall, but not always, and that this was dependent on the main diagenetic factor(s) at the burial location. Furthermore, good correlations are found between the microstructural preservation of bone and teeth; similar processes of decay were observed within bone and teeth of the same individual. Overall, the study demonstrated that histological analysis of bone is useful for the identification of degradation processes that affect biomolecular preservation in skeletal material. In this way, sample selection and analytical strategies can be optimized. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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D. M. Fyfe N. P. Chandler N. H. F. Wilson 《International Journal of Osteoarchaeology》1993,3(1):29-35
The alveolar bone condition of 34 pre-seventeenth century Solomon Island Polynesians aged 20–35 years was investigated from dental remains. The distance between the cementoenamel junction and the alveolar crest (CEJ-AC distance) was measured for six index teeth. The mean CEJ-AC measurements for each tooth, which ranged from 3.9 to 7.9 mm, greatly exceeded the distance of 2 mm frequently cited as representative of teeth supported by healthy bone. Many pathological bony defects were seen, suggestive of episodes of acute periodontitis with remissions to a quiescent phase. 相似文献
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C. N. Duckworth R. Córdoba de la Llave E. W. Faber D. J. Govantes Edwards J. Henderson 《Archaeometry》2015,57(1):27-50
Twenty‐six samples from domestic assemblages of 9th–12th century Córdoba were subjected to electron microprobe analysis. The results reveal two main compositional types. The first, encountered in 13 of the samples, seems to result from the combination of plant ashes with high‐impurity sand, and has some contemporary parallels from Syria and Egypt. The second type is a lead–soda–silica glass, encountered in a relatively high proportion of the glasses (11 of the 26 sampled), possibly formed by the addition of lead metal to existing glasses and with very few known parallels. These are among a very small number of results available to date on the chemical composition of glasses from medieval Spain, and the presence of a high proportion of lead–soda–silica glasses is particularly interesting, possibly indicating a technological practice unique to, or originating in, the western Muslim world. 相似文献
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THE EFFECT OF ACCESSIBILITY ON PRODUCTIVITY IN SPANISH MANUFACTURING FIRMS 总被引:1,自引:0,他引:1 下载免费PDF全文
David Martín‐Barroso Juan A. Núñez‐Serrano Francisco J. Velázquez 《Journal of regional science》2015,55(5):708-735
This paper evaluates the impact of accessibility on the productivity of Spanish manufacturing firms. We suggest the use of accessibility indicators of workers and commodities, integrating transport, land use, and individual components, computing real distances or traveling times using the Spanish full road network. Estimated firms’ total factor productivity is explained as a function of the accessibility indicators and additional control variables. Results evidence the crucial role on firms’ productivity to the accessibility of commodities and to a slightly lesser extent the workers. 相似文献
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Performance Goal Achievement in Fiscal Federalism: The Influence of State Partisan Environments and Regulatory Regimes 下载免费PDF全文
Jessica N. Terman 《政策研究杂志》2015,43(3):333-354
With tight budgets and hyper‐partisan interactions within and between the states and federal government, attention is being paid to the implementation of federal programs. This is particularly important because, as the recently implemented American Recovery and Reinvestment Act suggests, state administrators are often the implementers of federal policy. This study integrates the fiscal federalism literature with that on implementation and bureaucratic response to examine the effect that within‐state factors have on the degree of performance goal achievement in federally funded, state implemented programs. The findings suggest that, when implementing federal programs, state administrators face conflicting political incentive structures and policy‐specific capacity and capability deficits that influence their motivation and ability to achieve performance goals. 相似文献