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1.
Accelerator mass spectrometry (AMS) allows radiocarbon dating to be carried out by direct counting of14C atoms, rather than the conventional counting of radioactive disintegrations. The result is that samples up to 1000 times smaller can be handled. The approach was tested in principle by 1977 and for archaeological operation by 1983. More than 2000 samples per year are now being dated worldwide. The machines can now operate to about ± 80 years or better. Dates older than 40,000 years have not yet been achieved, but the ability to use small samples has already had considerable impact on dating the period 10,000–30,000 years ago. Bone is an ideal material for the new technique, since amino acids can normally be isolated and purified from gram-size samples. Studies of the origins of domestication are aided by the dating of individual grains and seeds. Because small samples can be mobile in the soil, careful sample selection strategies and procedures are required. The full impact of the technique can be assessed only through the rapid and comprehensive publication of archaeological results.  相似文献   
2.
The aim of this paper is to present the rich set of finds collected inside the grave Dibba 76/1, in the Emirate of Fujairah, during a season of rescue excavation conducted under the direction of S. Ali Hassan in 1994. The recovered grave‐goods include pottery, soft‐stone vessels, metal finds, personal ornaments, coins, and other items. Although comparable with other corpuses of material excavated in south‐eastern Arabia, the material of Dibba 76/1 stands out for the inner variety of the different artefacts’ classes and their remarkable chronological heterogeneity. The study of the grave‐goods suggests that Dibba 76/1 was reused over several centuries, showing a strong continuity in the funerary destination of this specific place from the end of the Wadi Suq period (2000–1600 BC) to the first phases of the late pre‐Islamic period (250 BC–AD 400), and the full integration of the area of Dibba in the succession of the various cultural facies known during this long time span.  相似文献   
3.
后工业社会中的大众传媒,尤其是电子传媒极大地影响着文学的生产、传播和消费.文学传媒化、商业化、大众化的趋势使人们不得不重新思考文学的走向与未来.大众传媒不仅是文学的工具,它也是文学本身不可分割的一部分.本文通过对梦枕貘<阴阳师>系列的个案分析,阐明日本当代文学和大众传媒之间的互动关系.  相似文献   
4.
Body mass is a key biometric that is useful in interpreting many aspects of an animal's life history. For many species, including dogs and wolves, methods for estimating body mass are not well developed. This paper assesses the utility of using limb dimensions to predict body mass in dogs and North American wolves. Regression analyses are utilized here to explore the correlations between limb dimensions and body masses of modern dogs and wolves, all of known body mass at death. These analyses reveal that a number of limb end dimensions are correlated with body mass in both dogs and wolves. Regression formulae generated through the analyses appear to allow body masses to be predicted with relatively small margins of error, often less than 10%. Formulae are calculated for groups with and without juveniles. In some cases, the dimensions of the juvenile specimens plot distinctly from those of adults, indicating that regression formulae specifically for juvenile canids may be needed. The strength of the limb dimension correlations is then compared with that of regression formulae for dog and wolf cranio‐mandibular dimensions. For the dogs, the cranio‐mandibular dimensions appear to slightly out‐perform the limb element dimensions in predicting body mass. The wolf limb dimensions, however, always appear to provide better predictions of body mass than do the skull dimensions. The newly developed regression formulae are applied to several Middle Holocene dog skeletons from Siberia for which previous body mass estimates are available, the latter based on cranial dimensions. These two sets of estimates are then compared. The overall results of our study indicate the need for further research, particularly with larger sample sizes, including more juvenile specimens. We also argue that work on body size estimation in single dog breeds may be warranted in some cases. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
5.
Osteoarthritis is the second most common pathology found in anthropological collections. Although a great deal is known about osteoarthritis, it is not yet known whether in skeletal populations there is a correlation between osteoarthritis and body mass. In this study, lower limb and spinal osteoarthritis scores were taken to determine whether body mass and femoral length correlate with osteoarthritis on weight bearing joints. Osteoarthritis was measured using a four-point ordinal scale on a sample of 114 adult prehistoric Californian Amerinds. Body mass was calculated from femoral head breadth; femoral length was measured using standard procedures; and age and sex were determined through standard osteological procedures. Using Spearman correlations, body mass and femoral length did not correlate significantly with any of the osteoarthritis variables. Age correlated significantly with nearly all of the osteoarthritis variables (hip, r = 0.507; knee, r = 0.528; cervical, r = 0.513; thoracic, r = 0.647; lumbar, r = 0.507, P-values < 0.001); and body mass and femoral length correlated with sex (r-values = 0.835 and 0.654, P-values < 0.001). With age and sex controls, body mass negatively correlated with the hip osteoarthritis variable (r = −0.202, P < 0.05), but not with any of the other osteoarthritis variables. Results concur with previous findings in the anthropological literature and highlight complexities of osteoarthritis etiology.  相似文献   
6.
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   
7.
民国元年广东北伐军为主体的东线北伐的胜利,对于捍卫南京临时政府、促使清帝退位,起了重要的作用。今年3月,是南京粤军阵亡将士墓建墓90周年。为了存史,本就粤军的兴建、征战、墓冢、勋绩,分别作了考证,藉以缅怀革命先烈。  相似文献   
8.
The quantitative assessment of COH fluids is crucial in modeling geological processes. The composition of fluids, and in particular their H2O/CO2 ratio, can influence the melting temperatures, the location of hydration or carbonation reactions, and the solute transport capability in several rock systems. In the scientific literature, COH fluids speciation has been generally assumed on the basis of thermodynamic calculations using equations of state of simple H2O–nonpolar gas systems (e.g., H2O–CO2–CH4). Only few authors dealt with the experimental determination of high‐pressure COH fluid species at different conditions, using diverse experimental and analytical approaches (e.g., piston cylinder + capsule piercing + gas chromatography/mass spectrometry; cold seal + silica glass capsules + Raman). In this contribution, we present a new methodology for the synthesis and the analysis of COH fluids in experimental capsules, which allows the quantitative determination of volatiles in the fluid by means of a capsule‐piercing device connected to a quadrupole mass spectrometer. COH fluids are synthesized starting from oxalic acid dihydrate at = amb and = 250°C in single capsules heated in a furnace, and at = 1 GPa and = 800°C using a piston‐cylinder apparatus and the double‐capsule technique to control the redox conditions employing the rhenium–rhenium oxide oxygen buffer. A quantitative analysis of H2O, CO2, CH4, CO, H2, O2, and N2 along with associated statistical errors is obtained by linear regression of the m/z data of the sample and of standard gas mixtures of known composition. The estimated uncertainties are typically <1% for H2O and CO2, and <5% for CO. Our results suggest that the COH fluid speciation is preserved during and after quench, as the experimental data closely mimic the thermodynamic model both in terms of bulk composition and fluid speciation.  相似文献   
9.
在先秦时期的中原,基地、墓葬的头向以及夫妻合葬墓中左右方位的选择,不断被赋予礼制的内涵,体现了我国古代丧葬制度不断发展、演变的过程。尤其是到周代,丧葬制度趋于完备。其中的茔域与方位之制,成为古代礼制的重要组成部分。  相似文献   
10.
成都市新都区新石器时代晚期土坑墓提取与保护   总被引:4,自引:4,他引:0       下载免费PDF全文
2008年1月,成都文物考古研究所与成都市新都区文物管理所在对一新石器时代晚期聚落遗址进行的考古发掘中,清理出土了二座竖穴土坑墓,其中M1墓葬人骨基本完整,具有较高的研究价值,但因年代久远和有害环境的影响,骨质已粉化,不便于直接提取人骨。为了有效地保护这一新石器时期人类骨骸,为后期的科学研究保存下这一珍贵的实物资料。决定采取套箱法对整座土坑墓进行提取的方式保护人骨,经过多方试验,确定采用A305黏结剂修复骨架裂纹,用GSA-102保护剂,B365作加固进行保护。经观察表明,本次土坑提取与保护取得了良好效果,并制定了一套科学的保护方案。该土坑墓的成功提取和科学保护,为今后在潮湿环境中的古遗址保护提供了可供借鉴的经验。  相似文献   
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