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971.
E. A. REBER  J. P. HART 《Archaeometry》2008,50(6):999-1017
Analysis was performed on absorbed and visible residues from 21 New York State prehistoric pottery sherds dating from 2905 ± 35 bp (Intcal04) (1256–998 cal bc ) to 425 ± 40 bp (Intcal04) (1417–1626 cal ad ). The use of pine resin was detected in 10 of 12 absorbed residue samples and 11 of 17 sherds subjected to visible residue analysis. It seems likely that the pots were resin‐sealed to make them more impermeable, constituting the first chemical evidence of extensive resin‐sealing in North America. A comparison of the results of absorbed and visible residues from eight of the sherds indicates that the two kinds of residue provide complementary evidence of vessel use.  相似文献   
972.
The occurrence of similar glass beads at archaeological sites in Africa and Asia bears witness to the trade relationship between the two continents. This paper reports elemental analysis results from a recent in‐depth laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) study of a group of archaeological glass beads with a specific alumina‐rich composition from East Africa, India and Sri Lanka. Based on the concentrations of the trace elements, two different subgroups were identified. One subgroup occurs at early periods (fourth century bce to fifth century ace ) in South India and Sri Lanka. The second subgroup appears at later dates in Africa and was identified at different Kenyan sites dated from the ninth to the 19th century ace , and at the contemporaneous site of Chaul in western India.  相似文献   
973.
974.
周滔  吕萍 《人文地理》2008,23(1):25-31
研究目的:基于城市边缘区居住用地的演替过程定量分析其空间分异性状,并基于此构建相应的改造模式.研究方法:信息熵模型分析.研究结果:城市边缘区居住用地的空问分异可以通过信息熵进行度量,基于度量结果,可以将其分为4种类型.根据各类型的特点分别设计相应的模式对其进行改造,以达成土地高效、合理以及可持续利用的目标.研究结论:居住用地的发展趋向是在时闻函数作用下不断增加着熵值.通过外界能量的输入即居住用地改造可改善土地利用状态,改造措施必须有一定的可行性、较低的费效比和一定的侧重点.  相似文献   
975.
976.
Chenque I site is a prehistoric cemetery located in Lihué Calel National Park (La Pampa province) in the Western Pampean region of Argentina. Hunter‐gatherer societies made use of this site during the Final Late Holocene for at least 700 years (1030–370 BP). Currently 41 burial structures have been excavated, and more than 150 individuals have been recovered. There is great variability in mortuary patterns at the site (simple, multiple, primary, secondary burials, and also a variant not previously observed in the region). The life‐ways of this population have been investigated through the evaluation of several biological and cultural factors. Several pathological conditions have also been identified in this cemetery. Burial no. 12 contains a skeleton of an adult male that shows multiple pathological lesions, compatible with a neoplastic disease. These lesions have been analysed using several methodological strategies: macroscopic, radiological and microscopic. This is the first time that this kind of disease has been identified from a prehistoric burial in Argentina. In this paper the location and characteristics of the lesions are evaluated, and the different neoplastic diseases that could have produced them are discussed. Since the people buried in this cemetery belonged to highly mobile societies, a key issue is to infer the consequences that this disease would have had on the dynamics of the group in which this person lived, because of the gradual deterioration of his health and physical strength. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
977.
The effect of skeletal exposure in a marine environment is an area of taphonomy that has been little investigated at the microscopic level. Understanding the peri‐mortem and subsequent post mortem history of deposition and/or redeposition is extremely important for event reconstruction and to identify deliberate or accidental redeposition. The material used for this study comes primarily from the Mary Rose shipwreck (a marine mass fatality dated AD 1545), and forensic material recovered from marine, lacustrine and terrestrial contexts is retrospectively referenced. Work presented here outlines a definitive type of marine exposure seen in temperate shallow off‐shore and intertidal marine contexts, and illustrates how it may be differentially identified from terrestrial deposition and exposure. Furthermore, the effects of rapid deposition on skeletal remains have been documented, and results indicate that marine organism fouling activity can be fully inhibited by rapid deposition of sediment. The responsible organism itself remains unidentified, but produces tunnels which are peripheral in their distribution and maintain fixed dimensions and morphology and are here associated with marine exposure. This type of microstructural change is unique and is not found in terrestrial or freshwater contexts. The study demonstrates a taphonomic microstructural change to bone and teeth which may be identified microscopically and interpreted as evidence of marine exposure. Secondarily, the history of depositional exposure between the two main Tudor layers has provided a new level of detail concerning exposure and site formation processes. The earliest Tudor layer formed rapidly over a period of months and contained no evidence of microstructural tunnelling, whereas microstructural tunnelling was seen exclusively in the second Tudor layer, formed over a period of decades, a period during which the ship's hull collapsed and a more open marine environment dominated. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
978.
Monitoring the degree of asymmetry in different parts of the human body can contribute to population studies, as it may be connected indirectly with the social structure, living conditions, and also with biomechanical stress affecting the person. Analysis of asymmetry may also assess preferential use of the right or left of the body during specific activities. This study is based on the measurements of bones of the upper and lower limbs of skeletons derived from the remarkable medieval cemeteries of Mikulčice‐Kostelisko (78 male, 132 female) and Prušánky (66 male, 69 female) (9th–12th centuries AD), and a series of skeletons representing a recent population from Bohemia (143 male, 157 female). The objective was to assess directional asymmetry (DA), fluctuating asymmetry (FA) and antisymmetry (AS) of the dimensions of the evaluated bones, and to use these data to compare the characteristics of the medieval and recent populations. DA was recorded in most dimensions. In the upper limb, the humerus exhibited the greatest expression of asymmetry, and, with the exception of the clavicle, DA was always more pronounced on the right side. Conversely, DA was less prevalent in the lower limb bones. It was more pronounced on the transverse, sagittal and circumferential dimensions of the diaphyses and epiphyses than on the length, and in most cases it was on the left side. The FA values were very low, and almost negligible in relation to the size. Nevertheless, FA was markedly more frequent on the lower than on the upper limb. In contrast to the medieval population, the recent population had higher FA and DA values. Thus, we propose that people from this medieval population were subjected to lower developmental stress than the recent sample. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
979.
Structured‐light illumination (SLI)‐based microscopy offers geologists a new perspective for screening of hydrocarbon‐bearing (HCFI) and small aqueous fluid inclusion (AFI) assemblages. This optical‐sectioning technique provides rapid, confocal‐like imaging, using relatively simple and inexpensive instrumentation. The 3D fluorescent images of HCFI planes and large single HCFIs permit the visualization of the relationships between HCFI assemblages, examination of HCFI morphology, and volume estimates of the fluorescent components within HCFIs. By the use of normal white light illumination, SLI image capture, and varying acquisition time it is also possible to image AFI because of the random movements of vapour bubbles within the inclusions. This allows the near‐simultaneous visualization of hydrocarbon and AFI which is of significant importance for the study of sedimentary basins and petroleum reservoirs. SLI is a unique and accessible 3D petrographic tool, with practical advantages over conventional epifluorescence and confocal laser scanning microscopy.  相似文献   
980.
Two‐phase flow and near‐critical phenomena are likely to enhance energy transport in high‐temperature hydrothermal systems. We present a series of two‐dimensional simulations of two‐phase flow of pure water at near‐critical conditions. The results show that at near‐critical conditions, two‐phase convection can be more efficient in transporting energy than single‐phase convection. The highest heat fluxes are attained when two‐phase heat‐pipes form near the bottom boundary, recharging the root of the upflow zone and thereby enabling the formation of broad upflow regions. When the system becomes more vapor‐dominated, it loses this ability, upflow zones become narrower and the energy efficiency drops to more moderate values.  相似文献   
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