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Pending the publication of new Soviet population data based on the 1979 census, to be hald next January, the author reviews population trends in the 1970's. After a steady decline through much of the Soviet period, birth rates and death rates have stabilized for the country as a whole, although marked regional differences continue. An unexplained rise in infant mortality and an apparent reduction of life expectancy have led to the suppression of data in these areas. No ready explanation is found for a recent increase in female fertility and age-specific death rates. Abnormalities in the age-sex structure, resulting from past population catastrophes, continue to persist and indicate future labor shortages. Geographical differences in population growth rates, resulting from differential rates of natural increase and migration, are analyzed. Urbanization, a typical phenomenon of the Soviet period, continues apace, with the biggest increases in large cities despite a policy designed to discourage big-city growth. A crucial question is the optimal disposition of the growing labor pool in the Central Asian region-whether to foster local employment or encourage migration from Central Asia to labor deficit areas elsewhere in the Soviet Union.  相似文献   
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The structures and compositions of modern and fossil charcoal samples were compared in order to evaluate charcoal degradation processes in archaeological sites. Modern charcoal samples produced in campfires contain two major phases: graphite-like microcrystallites and a non-organized phase. These phases create a mosaic-like structure with differing relative proportions depending on the taxonomic source of the wood used. Fossil charcoal samples (Tel Dor, Israel: 3000 years BP and Kebara Cave, Israel: 40,000 years BP) also contained the graphite-like microcrystallites and the non-organized phases, but were clearly altered compared to modern charcoal. The graphite-like phase of the fossil charcoal has much higher electrical resistivity, and its ESR properties show that it has markedly altered surface electronic states. Infrared spectra show the presence of additional carboxylate groups. Oxidation has therefore altered the structure. This appears to be a “self-humification” process that affects the graphitic component, and probably the non-organized phase as well.  相似文献   
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Mud constructed cooking installations such as ovens and hearths are common in modern, pre-modern and archaeological domestic contexts in West and Central Asia. Archaeological cooking installations are primarily identified using analogy of shape and size to ethnographic installations. The study presented here establishes direct evidence to the use of fire within mud constructed cooking installations, thus providing means for reducing ambiguity in identification of archaeological cooking installations. In addition, we present here a newly developed method that enables a clear-cut distinction between wood and dung ashes used as fuel materials in many modern and archaeological domestic contexts. The study is based on an ethnoarchaeological research in rural households at the Republic of Uzbekistan that was followed by geoarchaeological analyses of installation walls, wood ash, dung ash and wood and dung standards collected in the study area. Field work included ethnographic observations, interviews with informants and temperature measurements during cooking experiments. We show that changes in the clay mineral structure due to exposure to high temperatures on the interior walls of cooking installations can be detected using FTIR (Fourier Transform Infrared) spectroscopy, providing for the first time direct evidence to the use of fire within such installations. We demonstrate that the temperature recorded by clay alteration on installation walls as well as in the ashes left on installation bottoms does not correspond to baking or cooking temperatures. We also show that the newly developed method, based on the ratio of wood ash pseudomorphs to dung spherulites, separates between wood and dung ashes with very high certainty. Yet, we identify a range of values where differentiation between wood and dung ashes is uncertain, and suggest it results from intensive mixing processes. Lastly, we show that phytolith morphotype analysis is an insufficient tool, if used alone, for distinguishing wood from dung ashes in the study area. The newly developed tools for temperature estimation within mud constructed installations and for fuel origin determination contribute to better understanding of cooking-related practices, and can be applied to archaeological contexts worldwide.  相似文献   
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