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971.
S. A. Mays 《International Journal of Osteoarchaeology》2007,17(2):107-118
Recently, palaeopathologists have begun to diagnose brucellosis in skeletal remains from minor lytic lesions located on the anterior margins of one or some few vertebral bodies, taking these lesions to represent brucellar epiphysitis. However, review of the literature indicates that these lesions have been sporadically noted for some time by palaeopathologists and various different interpretations have been placed upon them. In view of this, a study of these vertebral marginal lesions (VML) was undertaken in a large series of archaeological skeletons from England, with the aim of characterising their morphology and frequency and shedding light upon their causes. In the study material, VML were found only in the lumbar spine, where they occurred with a prevalence of approximately 4%. It was argued that VML are consistent with two principal alternative diagnoses: brucellosis and traumatic anterior disc herniation. Differentiating these possibilities for the VML in the study material was difficult, but the balance of the evidence seemed to favour traumatic anterior disc herniation as the more likely cause. It is concluded that VML should not be used to identify the presence of brucellosis in skeletal remains unless there is further evidence, in the form of additional skeletal lesions or biomolecular evidence for residual brucella bacterial DNA, to support such a diagnosis. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
972.
Differentiation of the genetic and the acquired anaemias, particularly in areas of the world where they may co‐exist, has been a challenge for palaeopathologists for over 100 years. In this paper we present macroscopic and radiographic skeletal lesions that are associated with the thalassemias in a 14‐year‐old girl from a modern reference collection of the University of Athens. This individual is of known sex, age, cause of death, place and dates of birth and death. The case is examined in terms of epidemiology, growth, distribution and severity of lesions and differential diagnosis. The entire skeleton is affected by marrow hyperplasia: lesions of the axial skeleton are extreme, and the appendicular skeleton is severely affected as well. The odontofacial manifestations that are diagnostic of thalassemia and differentiate it from other anaemias are present and include: maxillary and mandibular hyperplasia, reduced sinuses, displacement of maxillary dental structures, overbite, and generalised osteopenia. The development of extreme bone lesions and the ‘advanced’ age‐at‐death of this individual is explained as either the result of thalassemia major under a low transfusion regimen that was the norm during her lifetime, or to a form of thalassemia intermedia that allows survival to later life at the expense of gross skeletal alterations. The present status of skeletal studies in Greece does not support the identification of a genetic anaemia in past populations. The potential contribution of the current analysis in differentiating the anaemias in antiquity is evaluated. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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976.
Mineral deposits in the Cupp‐Coutunn/Promeszutochnaya cave system (Turkmenia, central Asia) record a phase of hydrothermal activity within a pre‐existing karstic groundwater conduit system. Hydrothermal fluids entered the caves through fault zones and deposited sulphate, sulphide and carbonate minerals under phreatic conditions. Locally, intense alteration of limestone wall rocks also occurred at this stage. Elsewhere in the region, similar faults contain economic quantities of galena and elemental sulphur mineralization. Comparisons between the Pb and S isotope compositions of minerals found in cave and ore deposits confirm the link between economic mineralization and hydrothermal activity at Cupp‐Coutunn. The predominance of sulphate mineralization in Cupp‐Coutunn implies that the fluids were more oxidized in the higher permeability zone associated with the karst aquifer. A slight increase in the δ34S of sulphate minerals and a corresponding δ34S decrease in sulphides suggest that partial isotopic equilibration occurred during oxidation. Carbonate minerals indicate that the hydrothermal fluid was enriched in 18O (δ18OSMOW ~ + 10‰) relative to meteoric groundwater and seawater. Estimated values for δ13CDIC (δ13CPDB ~ ? 13‰) are consistent with compositions expected for dissolved inorganic carbon (DIC) derived from the products of thermal decomposition of organic matter and dissolution of marine carbonate. Values derived for δ13CDIC and δ18Owater indicate that the hydrothermal fluid was of basinal brine origin, generated by extensive water–rock interaction. Following the hydrothermal phase, speleothemic minerals were precipitated under vadose conditions. Speleothemic sulphates show a bimodal sulphur isotope distribution. One group has compositions similar to the hydrothermal sulphates, whilst the second group is characterized by higher δ34S values. This latter group may either record the effects of microbial sulphate reduction, or reflect the introduction of sulphate‐rich groundwater generated by the dissolution of overlying evaporites. Oxygen isotope compositions show that calcite speleothems were precipitated from nonthermal groundwater of meteoric origin. Carbonate speleothems are relatively enriched in 13C compared to most cave deposits, but can be explained by normal speleothem‐forming processes under thin, arid‐zone soils dominated by C4 vegetation. However, the presence of sulphate speleothems, with isotopic compositions indicative of the oxidation of hydrothermal sulphide, implies that CO2 derived by reaction of limestone with sulphuric acid (‘condensation corrosion’) contributed to the formation of 13C‐enriched speleothem deposits. 相似文献
977.
J. Pironon R. Thiery M. Ayt Ougougdal S. Teinturier G. Beaudoin F. Walgenwitz 《Geofluids》2001,1(1):2-10
A recent advancement in petroleum geochemistry is to model fossil oil composition using microthermometric and volumetric data acquired from individual fluid inclusion analysis. Fourier transform infrared (FT‐IR) microspectroscopy can record compositional information related to gas (CH4 and CO2) and alkane contents of petroleum inclusions. In this study, a quantitative procedure for FT‐IR microspectrometry has been developed to obtain, from individual fluid inclusions, mol percentage concentrations of methane, alkanes and carbon dioxide as constraints to thermodynamic modelling. A petroleum inclusion in a sample from the Québec City Promontory nappe area was used as standard to record a reference spectrum of methane. The analytical procedure is based on the measurement of CH4/alkane and CH4/CO2 band area ratios. CH4/alkane infrared band area ratio is obtained after spectral subtraction of the reference methane spectrum. This area ratio, affected by absolute absorption intensities of methane, methyl and methylene, provides a molar CH4/alkane ratio. Methyl/methylene ratio (CH2/CH3) ratio is obtained following procedures established in previous work. CO2/CH4 concentration ratio is estimated from relative absolute absorption intensities. Application to natural inclusions from different environments shows good correlation between FT‐IR quantification and PIT (petroleum inclusion thermodynamic) modelling. 相似文献
978.
S. Blau 《International Journal of Osteoarchaeology》2005,15(4):291-297
The partial remains of a child's cranium were examined as part of a three‐year research project investigating the health and population movements of prehistoric communities in western Central Asia. Differential diagnoses are provided for an unusual aperture observed at the bregma. Possible aetiologies for the aperture include congenital and developmental defects, pathological alterations, surgical intervention, trauma and post‐mortem changes. The lesion presented in this article is interesting in terms of the contribution it makes to our understanding of the types of possible diseases that existed in the past, in this relatively understudied part of the world. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
979.
S. M. BARNETT 《Archaeometry》2000,42(2):431-457
Dating of later prehistoric settlements relies heavily on potter; typologies in England and yet there has been little scientific dating in order to verify these typologies. In this work, luminescence dating techniques were applied directly to the pottery which forms the typological framework. Excellent agreement was obtained between the luminescence ages, and archaeological age ranges for known‐age pottery sherds with diagnostic form and surface decoration. A lower correlation, however, was found in several regions between the luminescence ages for undecorated body sherds and the archaeological assessment which was necessarily based solely on fabric, suggesting the need for reassessment of these fabric chronologies. 相似文献
980.
Recently several anthropological and sociological studies have interpreted technologies as cultural choices that are determined as much by local perceptions and the social context fly any material constraints or purely functional criteria. Using the example of ceramic technology we consider how materials science studies can contribute to and benefit from this understanding of technology as a social construct. Although we acknowledge some potential difficulties, it is our contention that both materials scientists and archaeologists have gained much and have much to gain by cooperating together to study ancient technologies, and that the concept of ‘technological choices’can facilitate a wider consideration of the factors shaping technological developments. 相似文献