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901.
902.
The problem relating to the emergence of ancient agriculture and the specifi c character of its development in Western Siberia is considered on the basis of paleobotanical data analysis. This article provides information on basic methods of searching and identifying phytoliths, grains (or grain prints), and pollen of domesticated cereals, as well as evaluates the feasibility for using these techniques in examining this problem. Currently known paleobotanical indicators of agriculture in Western Siberia, Kazakhstan, the Altai, and Zhetysu are summarized, and new indicators are presented. The attempt at reconstructing the centers for cultivating domesticated cereals starting in the Late Bronze Age is based on the analysis of spatial and temporal distribution of the cereals’ grains and pollen.  相似文献   
903.
Cranial series from the Ust-Ishim burial grounds represent the medieval population of the southern taiga zone of the Middle Irtysh. Indirect data suggests that in the 5th–8th centuries AD, the area was populated by people akin to the low-faced Mongoloids who had lived in the Western Siberian forest steppe in the Early Iron Age. Apart from that, a very small Southern Siberian Mongoloid admixture is present. Generally, the Ust-Ishim people are similar to the Tobol–Irtysh group of populations belonging to the Ob–Irtysh variety of the Western Siberian race. Among the modern populations, those closest to the Ust-Ishim people are the Tobol-Irtysh Tatars, implying genetic continuity with the medieval groups studied by us.  相似文献   
904.
In prehistory, serpentinite was one of the most frequently used raw materials to produce polished stone artefacts. Several conventional analytical techniques can be applied to identify the serpentine minerals, but their application generally requires a powdered sample. This implies that the artefacts to be analysed must be damaged, and the possibility of analysing a mixture of different serpentine polytypes is high. The use of spatially resolved techniques is therefore a necessity to overcome this problem. Several thin sections of serpentinitic rocks and prehistoric axes have been analysed by synchrotron radiation Fourier transform infrared micro‐spectroscopy. The spectra were acquired directly on specific points of polished stone artefacts and this allowed the recognition of the different polytypes of serpentine minerals without causing any damage to the objects. The results show the infrared micro‐spectroscopy technique to be a useful tool for the characterization of archaeological lithic material.  相似文献   
905.
Wetlands are common in Coastal Western Hemlock forests yet the hydrologic processes that generate runoff from small swamps are not completely understood. Direct field observations, hydrologic, and electrical conductivity data were collected from a gently sloping forested swamp complex from July to November 2009. Swamps occupied depressions between raised mounds (0.1 to 3 m high) and were connected by an ephemeral creek. Runoff was controlled by antecedent moisture conditions and influenced by basin microtopography. Two hydrologic regimes occurred during the study period and different runoff processes dominated each regime. Runoff was generated by subsurface flow during dry antecedent conditions as swamps remained hydrologically disconnected from each other. Runoff was generated by surface outflow from hydrologically connected swamps during wet antecedent conditions as ponded water spilled out of the depressions. The forested swamp complex produced a faster but limited hydrologic response during dry antecedent conditions compared to a slower but greater hydrologic response during wet antecedent conditions. Stormwater runoff and runoff ratios were up to two orders of magnitude higher in wet conditions than during similarly sized events in dry conditions. These factors should be considered when designing monitoring programs or runoff models in forested swamps with significant microtopography. Field surveys and estimates of hydrologic inputs and outputs may be useful in predicting the potential hydrologic connectivity of isolated forested swamps.  相似文献   
906.
Seasonal patterns of Native American residence and use of shell mounds of the San Francisco Bay area, California are of great interest. This work investigates seasonal occupation by means of a new method for interpretation of geochemical data from Mytilus trossulus specimens recovered from one of these structures, the Ellis Landing Shell Mound (CA-CCO-295). The approach, which is suitable for relatively small shell fragments from a variety of archaeological contexts, is used to infer the environmental conditions (temperature and salinity of ambient water) at harvest time, compared with average conditions for the period, and thus estimate the season during which the shells were harvested. This information, in turn, is employed to evaluate current models about the growth and construction of prehistoric shell mounds in San Francisco Bay. The method was applied to seven different lenses in the shell mound ranging in age from ∼240 cal yr BP to ∼3510 cal yr BP. We found that, although seasonal occupation varied over time, it generally was confined to summer through late fall, with little indication of winter gathering. Our findings suggest that California shell mounds, such as Ellis Landing, were constructed in a very different manner than some other mounded places used by contemporaneous hunter-gatherers elsewhere in North America.  相似文献   
907.
908.
Numerous Hellenic terms have been gradually adopted during the development of modern medical science. Moreover, there are a significant number of words that derive directly from the Hippocratic texts. Hippocrates (ca. 460-ca. 377 BC), revered as the father of medicine, and his followers left behind a valuable heritage of medical knowledge that, practically, laid the foundations of Western medicine. Their theories, collected in Corpus Hippocraticum, transformed medicine by adding, mainly, clinical observation and inductive reasoning as significant parts of medical diagnosis and treatment. Additionally, Hippocratic writings have provided an invaluable heritage of medical terms for all medical fields. The present article examines the Hellenic and Hippocratic terminology referring to the spine and how this vocabulary has influenced and dominated upon modern spinal onomatology.  相似文献   
909.
Using ancient DNA (aDNA) extracted from eggshell of the extinct moa (Aves: Dinornithiformes) we determined the species composition and number of eggs found in a late thirteenth century earth oven feature at Wairau Bar (South Island, New Zealand) – one of New Zealand’s most significant archaeological sites. Mitochondrial and nuclear DNA signatures confirmed this oven feature contained fragments of at least 31 moa eggs, representing three moa genera: Emeus; Euryapteryx; Dinornis. We demonstrate through the genetic identification of 127 moa eggshell fragments that thickness is an unreliable character for species assignment. We also present a protocol for assessing the preservation likelihood of DNA in burnt eggshell. This is useful because eggshell fragments found in archaeological contexts have often been thermally modified, and heat significantly increases DNA fragmentation. Eggshell is widely used in radiocarbon dating and stable isotope research, this study showcases how aDNA can also add to our knowledge of eggshell in both archaeological and palaeoecological contexts.  相似文献   
910.
青海藏族聚居区实现长治久安的思考及对策   总被引:1,自引:0,他引:1  
在现代社会,民族问题是影响国家和社会长期稳定的重要因素之一。本文对青海藏族聚居区的长治久安问题进行了客观分析并针对政府决策和执行提出了对策建议。  相似文献   
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