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H.P. Schwarcz W.M. Buhay R. Grün H. Valladas E. Tchernov O. Bar-Yosef B. Vandermeersch 《Journal of archaeological science》1989,16(6)
In 1985 a Neanderthal skeleton was found in the cave of Kebara in southern Mt. Carmel. Electron spin resonance (ESR) dates have been obtained on tooth enamel of gazelles found in layer X, just overlying the layer in which the skeleton was found. Assuming early uptake of uranium by the teeth, they yield an age of 60 ± 6 ka; assuming gradual, linear uptake of uranium yields an age of 64 ± 6 ka. Both age estimates are consistent with a previous estimate for the skeleton, based on TL dating of burnt flint, of 60 ± 4 ka. 相似文献
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Riddell JB 《Progress in human geography》1989,13(2):267-276
Progress in development geography has been recently associated with the shift of the perspective on underdevelopment from a right-wing, conservative standpoint to a leftward, liberal-radical position. Marxism often conceals its message in obscure rhetoric with moral overtones on colonialism, slavery, poverty, and underdevelopment. Liberal academics have lamely acceded to the dogmas of this once-assertive ideology. Marxist view have exerted a stimulus on debates, but could not provide answers to the issues of this discipline. The hopes of development and prosperity a generation ago have evaporated only to be replaced by news of economic malaise, the food crisis, and crushing debt. In the late 1980's geographers addressed Third World environmental issues. Blaikie and Brookfield examined environmental deterioration among elements of the population-environment issue. Lewis and Berry dealt with African environments and resources. Watts and Bassett touched on agrarian and political concerns in West Africa. Adams examined water resources development in Nigeria's Sokoto Valley. Bryceson analyzed the political economy of agriculture in Tanzania. Lawson depicted how government policy bore on agriculture and its regional pattern. Crush detailed the absorption of Swazi labor into the South African economy. Dayal described the deficiency diet of agricultural workers in Bangladesh. Others examined Africa's financial disaster, Japan's trade surplus, and the global population crisis. Nevertheless, the dearth of output on and neglect of Third World issues by human geographers awaits positive research publications. 相似文献
44.
The interrelationships between macro and micro factors in the analysis of interstate migration in the United States are explored. A synthesis between these factors is attempted "by combining objectively calibrated characteristics of states with their subjectively measured counterparts....First, the relationships between the objective variables and their subjective counterparts are analyzed. Second, both sets of variables are used to explain residential preferences and migration. Third, a series of path models are constructed to indicate how the subjective variables act as intervening variables between their objective counterparts and migration." 相似文献
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