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991.
992.
David F. Lindenfeld 《History and theory》1999,38(3):281-299
This article seeks to integrate the roles of structure and human agency in a theory of historical causation, using the fall of the Weimar Republic and in particular Henry Turner's book Hitler's Thirty Days to Power as a case study. Drawing on analogies from chaos theory, it argues that crisis situations in history exhibit sensitive dependence on local conditions, which are always changing. This undermines the distinction between causes and conditions (including counterfactual conditions). It urges instead a distinction between empowering and constraining causes of specific human actions as a more fruitful model. The paper also discusses more briefly two other analogies to chaos theory: 1) similarity across differences in scale as applicable to different levels of individual (psychological) and collective events, which are seen as homologous; 2) a model of branching as applicable to the totality of causes of a given event. 相似文献
993.
994.
Charles F. Merbs 《International Journal of Osteoarchaeology》2002,12(4):279-290
Inuit skeletons from archaeological sites in Arctic Canada were examined for the presence of spondylolysis. The largest series represent the Thule culture and historic Inuit from northwest Hudson Bay and Labrador, and Sadlermiut from Southampton Island. The condition was found in 90 individuals, with a total of 120 affected vertebrae producing 198 hemi‐arch defect sites. As in other studies, L5 is affected most frequently, followed by L4 and L3, but examples of L1, L2, L6, and S1 involvement are represented. Incomplete separations account for 20% (40) of the 198 defects, and 5% (10) occur at sites other than interarticularis. Affected males outnumber females at a ratio of 2.4 to 1. The condition was found to increase in frequency from adolescence to young adulthood, and then decrease to middle adulthood and decrease again to old adulthood, but the drop in frequency with age in the adult categories is significant only at the .20 level. Where comparisons could be made, the data obtained from the Canadian Inuit closely resemble those obtained from Alaskan Eskimos and Aleuts, especially their closest linguistic relatives, Inupiat speakers in northern Alaska. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
995.
用扫描电子显微镜(SEM)及所配备的能谱仪(EDS)、X-射线衍射仪(XRD)对出土的三块宝石的化学及矿物学性质进行了分析研究,结果表明,其中两块宝石为金柄剑镶嵌宝石,其化学组成为绿松石,另一块宝石并非来自铁剑镶嵌物,具有正长石和钙长石的衍射谱图特征;绿松石加工制作过程曾使用了青铜工具进行表面打磨处理,说明我国在春秋时期已经开始使用青铜打磨工具。 相似文献
996.
The role of labrid fish in prehistoric economics in New Zealand 总被引:1,自引:0,他引:1
Labrids are one of the most common types of fish to occur in inshore rocky marine habitats in New Zealand. There are major discontinuities in their relative abundance in archaeological sites from different regions of New Zealand, and these are difficult to reconcile with known distributional patterns. A number of possible explanations are examined such as changes in fishing technology and various ecological factors. It is concluded that the reasons for these observed fluctuations may vary considerably from one case to another, but where large numbers were caught by prehistoric people who had access to alternative fish resources, unreliability of some major aspect of the economy may be inferred. A combination of poor sea conditions and marginal horticulture is likely to increase the importance of labrid fish. 相似文献
997.
We report δ18O and δ13C data from modern carbonate in soils and dung samples from 3 recently abandoned livestock corrals in northern Kenya. Calcium carbonate content is higher within ∼5 cm depth that contains a mixture of dung and surface soils of corrals than in soils below 5 cm depth. We radiocarbon dated carbonates from 0.5 to 40 cm depths in two corrals and one control site. Surface carbonates (0.5 cm) from the two corrals were formed from modern carbon (>1955) when the corrals were active, while all other carbon is >16,000 years (BP) old. Shallow carbonate is also enriched in 18O (δ18O up to 3.0‰) and depleted in 13C (δ13C up to −12.0‰) with respect to carbonate at deeper levels and at two control sites. The δ18O and δ13C of soil carbonates (δ18OSC and δ13CSC respectively) in corrals are inversely correlated for depths up to about 15 cm where organic carbon is greater than 0.5%. Below that depth, there is a positive correlation between δ18OSC and δ13CSC values, similar to that observed in a control site. 相似文献
998.
Noah V. Honch T.F.G. Higham J. Chapman B. Gaydarska R.E.M. Hedges 《Journal of archaeological science》2006
Stable isotope analyses have been applied to human and faunal bone collagen from the Varna I and Durankulak cemeteries to explore palaeodietary adaptations in the Neolithic and Eneolithic (Copper Age). The results suggest both populations primarily utilised terrestrial, C3-based diets, despite their proximity to the Black Sea. The wider δ15N range of the Durankulak humans likely indicates the differential utilisation of terrestrial meat sources, which is probably related to the degree to which primary and/or secondary ovicaprid products were consumed, particularly since ovicaprid δ15N values differ from other herbivores. The isotopic distribution of Varna I reflects a linear relationship between δ15N and δ13C, suggesting that a minority of individuals enriched in both isotopic parameters supplemented their diets with marine resources. These burials include the well known ‘chieftain’ (burial 43) and show notable material wealth by way of grave goods. At the population level, however, there is no significant correlation between stable isotope values and material wealth at Varna I, a fact with implications for theories regarding emergent social/economic hierarchies in Balkan prehistory. Five burials at Durankulak were found to have relatively enriched δ13C and δ15N values with respect to the rest of the population. These burials reflect a prominently marine-based or mixed terrestrial C3-based diet that included C4 inputs, possibly from millet, for which the limitations of stable isotope analysis on bulk collagen are not able to differentiate. AMS dating has shown that these burials belong to a much later period. 相似文献
999.
1000.