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941.
R. Chen  G. Tian  W. Zhao  Y. Wang  Q. Yang 《Archaeometry》2018,60(5):1122-1134
The study aims at providing the spatial distribution and potential structure of the burial mounds at the Sifangling site, Hepu Han Tombs, in southern China. We implemented an electrical resistivity tomography (ERT) technique to obtain high‐resolution imaging of archaeological targets, considering the challenging environment and the depth of the burials. Three ERT profiles were tested above a small ancient mound previously detected by exhaustive archaeological drillings, following which 18 ERT profiles with angular separation were performed on the largest mound at the test site, without any a priori archaeological evidence below the surface. Then, a series of two‐dimensional (2D) profiles were combined as a ‘pseudo‐3D’ volume, which allowed a detailed characterization of the burial mound, and iso‐resistivity surfaces were also calculated to emphasize the location and spatial extent of the target. The results gave an effective identification of the funeral chamber and its structural details, and allowed detailed pre‐excavation planning.  相似文献   
942.
The period of the Atlantic slave trade between Africa and European colonies is relatively well documented compared with the historic records of many regions of precolonial Africa. However, this documentation necessarily presents a perspective distilled through European eyes. This paper suggests a methodology influenced byAnnales history for critically analyzing documentary sources in conjunction with a critical interpretation of archaeological remains. Archaeological evidence from recent excavations at the site of Savi, capital of the Hueda kingdom, is contrasted with documentary evidence, facilitating an interpretation of motivations guiding Hueda interaction with European traders and structuring their spatial relationship.  相似文献   
943.
944.
The 1986 accident at the Chernobyl nuclear power plant in Ukraine produced severe environmental health problems. This paper reports on the environmental health conditions in Ukraine after the accident and the health policy approaches employed to respond to the environmental conditions and health problems. Crisis conditions and a period of rapid change in Ukraine contributed to the difficulties of developing and implementing policy to address serious environmental health problems. Despite these difficulties, Ukraine is taking effective action. The paper describes the primary environmental health problem areas and the efforts taken to solve them. The effect of intense public fear of radiation on policymaking is described. The paper discusses the ability of public fear to distort health policy towards certain problems, leaving problems of greater importance with fewer resources.  相似文献   
945.
946.
947.
Statistics calculated using the means of geographic areas can differ substantially from the corresponding statistics based on data from individuals. Analysts who base their conclusions about individual-level relationships on area-level analyses run the risk of committing the ecological fallacy. Statistical models are proposed that capture the essential features of the structure of a population composed of geographically defined groups and can encompass grouping processes and contextual effects. These models are used to show how small effects in the analysis of individual-level data can be magnified substantially when the corresponding analysis based on aggregated data is carried out. Thus the source of aggregation effects is exposed. While aggregation effects have been studied by many authors, no general approach has been offered to the problem of adjusting an area-level analysis so as to correct for aggregation effects and hence remove, or at least reduce, the bias that leads to the ecological fallacy. The statistical models proposed are used to provide an approach to this problem. Data from the 1991 U.K. Census of Housing and Population are used to illustrate the size of the aggregation effects and the extent to which the proposed adjustments succeed in their objective.  相似文献   
948.
Whereas the beginning part of Charcot's career was occupied with a rigorous and unerring devotion to the anatomo-clinical method, his later career shared attention with physiologic and psychological analyses of hysteria. The seeming paradox between these differing approaches to neurologic study can be better understood by an analysis of Charcot's work on aphasia. This area of study grew out of Charcot's larger research effort on cerebral localization, but was not well known, because most of his lectures on aphasia were never widely published or distributed in either French or English. In analyzing aphasia, Charcot began with anatomic lesions, but gradually incorporated cases of hysterical aphasia, as evidence of dynamic lesions of the same brain areas. Although aphasia never represented a prominent area of study for Charcot, it held a particularly important place in his career first because it provided this transition between anatomic and physiologic approaches to neurologic research, and second because it permitted a natural two-way passage between the topics of cerebral localization and hysteria.  相似文献   
949.
Nearly 200 new lead isotope analyses of sulphidic and oxidized ores from 26 copper mines on Cyprus show that the mines from different geological regions group in five distinctive isotopic groups, each with a substructure, related to the geological history of the ore formation. Comparison of lead isotope compositions of Bronze Age artefacts with these data can in many cases reveal the actual mines from which the copper for particular artefacts was obtained. The particular case of the provenance of the copper for 78 Late Bronze Age copper ‘oxhide ingots’found in Cyprus, Crete, Greece, Sardinia, Turkey and Bulgaria is discussed. The data show that all oxhide ingots so far analysed, dating to the fourteenth century BC and later, were made of copper consistent isotopically with only one mining region in the geographical north of Cyprus, and especially the Apliki mine. The study provides further evidence which supports the validity of the conventional approach to the use of lead isotope analysis for provenancing metals; this evidence is antithetical to recent suggestions of a model for the production of copper oxhide ingots which involved widespread mixing of copper from a number of ore sources throughout the Mediterranean.  相似文献   
950.
Archaeological artefacts identified as jet are often assumed to have originated from the principal British source, which is at Whitby in Yorkshire. Geological samples of jet have also been found within the Kimmeridge Blackstone in Dorset—a seam of oil shale which has been worked since prehistoric times to produce artefacts similar to those made from jet. This paper discusses the geology and geochemistry of jet samples from both Whitby and Kimmeridge, and shows that the geological samples can be discriminated by differences in their organic components, as elucidated by Fourier transform infrared spectroscopy and pyrolysis-gas chromatography/mass spectrometry.  相似文献   
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