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251.
Oxygen is a key parameter in the degradation of archaeological material, but little is known of its dynamics in situ. In this study, 10 optical oxygen sensors placed in a 2 m deep test pit in the cultural deposits at Bryggen in Bergen have monitored oxygen concentrations every half hour for more than a year. It is shown that there is a significant spatial and temporal variation in the oxygen concentration, which is correlated to measured soil characteristics, precipitation, soil water content and degradation of organic material. In these deposits oxygen typically occurs when the air content of the soil exceeds 10–15% vol, while oxygen dissolved in infiltrating rainwater is of less importance for the supply of oxygen in the unsaturated zone.  相似文献   
252.
253.
However private they may seem, emotions depend for their meanings on the communities in which they are expressed. But if emotions are shaped by and for their communities, how can we account for emotional change? After briefly surveying how historians have (1) defined the communities in which emotions have been expressed and (2) explained how and why emotions have changed, this article turns to the community of the Waorani of Amazonian Ecuador. It explores whether anthropological explanations of emotional change in that “test case” may help the historian. The answer is not entirely positive. The article concludes with some thoughts about what sorts of collaborations between historians and anthropologists might be more productive for emotions studies.  相似文献   
254.
Environmental change has a human dimension, and has had so for at least the last 10 000 years. The prehistoric impact of people on the Arctic landscape has occasionally left visible traces, such as house and field structures. More often than not, however, the only evidence available is at the microscopic or geochemical level, such as fossil insect and seed assemblages or changes in the physical and chemical properties of soils and sediments. These records are the subject of SEAD, a multidisciplinary database and software project currently underway at Umeå University, Sweden, which aims to create an online database and set of tools for investigating these traces, as part of an international research infrastructure for palaeoecology and environmental archaeology.  相似文献   
255.
Samples of Roman thin‐walled ware from Segesta (northwestern Sicily), dating back to the early Imperial period, were studied by optical microscopy (OM) and Neutron Activation Analysis (NAA). Up to now, this class of Roman fine tableware has only occasionally been evaluated archaeometrically. Nevertheless, numerous production centres are believed to have been simultaneously active in the western Mediterranean area. Petrographic and chemical data seem to be in agreement with the archaeological hypothesis of local manufacture in Segesta for most of the analysed samples, through a comparison with kiln wasters and local raw materials. The effectiveness of thin‐section petrography for determining the provenance of such a tiny tempered class of pottery and the integrated use of two different grouping procedures (petrography and chemistry) were also tested.  相似文献   
256.
Summary. The Ashmolean Museum possesses a small group of Late Mycenaean (Late Helladic IIIC) sherds from Kazanli in Southern Cilicia, which it acquired in 1930. These are of interest since, although similar pottery is known from nearby Tarsus, they appear to be slightly later in date than most of the other pottery from Kazanli recovered by excavation or surface survey. One of them has a pictorial representation of an unusual nature.
The appearance of Mycenaean pottery in Cilicia has often been associated with the arrival of Mycenaean settlers (particularly refugee settlers) around 1200 B.C. However, it is doubtful whether the pottery really justifies this interpretation. Where identifiable, the Cilician Mycenaean seems to display closer links with Cyprus and the East Aegean than with the Greek Mainland; and, when other evidence is taken into account, there seems little reason to suppose that it is necessarily the result of colonisation from Mycenaean Greece.  相似文献   
257.
Is it possible to identify cooked, rather than burnt, bone? Mild heating (≤100 °C,1 h) – typical of cooking – does not lead to detectable changes in any biochemical parameter of bone yet measured. If it is only possible to detect charred bone, how is it possible to detect cooking in the archaeological record? In a previous paper (Koon et al., 2003, J. Arch. Sci.), we used a Transmission Electron Microscopy (TEM) based approach to investigate changes in the organization of the bone protein, collagen, as it is heated, using bone from heating experiments and short term burials. The work revealed that mineralized collagen, despite requiring aggressive treatment to gelatinise the protein (e.g. 90 °C, 240+ h), readily accumulates minor damage. We believe that the presence of mineral matrix stabilises the collagen enabling the damage to accumulate, but preventing it from causing immediate gelatinisation. Once the mineral is removed, the damage can be observed using appropriate visualization methods.  相似文献   
258.
A human skull, buried about 2500 years ago in a Bronze Age cemetery at Jinggouzi, a site of an important ethnic group in ancient China, appeared to have characteristics of fibrous dysplasia. The CT images indicated a reduction in bone density and relatively homogeneous lesions. More features were revealed using CT reconstruction techniques. Lesions seen in low‐magnification images using a 3D deep‐field microscope had an irregular honeycomb‐like structure. At higher magnification, the trabeculae morphology and the gaps between the trabeculae were irregular and varied in size and shape. Paraffin‐embedded specimens stained with HE showed trabeculae with tortuous irregular arrangements varying in shape and width. The irregular trabeculae of woven bone has been described as having fibrous dysplasia. Molecular analysis of the GNAS gene indicated no mutation. This provides a non‐invasive approach for us to make more comprehensive diagnoses and to assist research into ancient human diseases.  相似文献   
259.
Yelang (夜郎), a mysterious state located in the south‐western area of early China and dating from the Bronze Age to the Early Iron Age (1300 bc – ad 25), is a cultural interactive junction between the Yunnan–Guizhou Plateau and the Yangtze River Basin. The Zhongshui Basin in Weining County, Guizhou Province, was one of the important distribution areas of the Yelang civilization. This area, which includes sites at Jigongshan (鸡公山; 1300 – 800 bc ), Hongyingpan (红营盘; 700 – 400 bc ) and Yinzitan (银子坛; 400 bc – ad 25), has provided a very integrated chronology, spanning from the Bronze Age to the Early Iron Age in the eastern Yunnan – western Guizhou area. To investigate human migration and horse‐trading at these Yelang sites, we conducted a strontium isotopic analysis on the teeth enamel of humans and horses unearthed from these three sites. The results indicated the following: (1) people at the earlier sites (Jigongshan and Hongyingpan) were all indigenous, whereas in the Yinzitan cemetery, there was a more immigrant population, and all the people who were buried in an upper limb flexed supine position were non‐local; and (2) most of the horses found at the Jigongshan and Yinzitan sites show different provenances, probably related to the famous Dian (滇) and Zuo (筰) horses recorded in historical documents, providing more clues for further study on horse‐trading in South‐West China during the Bronze Age and the Early Iron Age.  相似文献   
260.
Lead isotope compositions provide a direct means of assessing provenance. The lead contents in bronzes cannot be used to argue against lead isotopes. Any claim for the origin of the source material for the origin of Yin‐Shang bronzes must satisfy the measured lead isotope compositions. Thus far, only southern African sources are found to meet this criteria.  相似文献   
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