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101.
Some 630 Roman silver coins excavated at Augusta Raurica (Switzerland) have been analysed by non-destructive X-ray fluorescence and X-ray diffraction. Furthermore, the density and the weight have been determined. The measured average density of plated and massive depletion-silvered coins is lower than the density calculated from the chemical composition, whereas massive coins display equal values for both of the densities. Based on experimental X-ray investigations of modern silver (tempering, acid treatment, production of corrosion layers), the nature of corrosion products on silver, their impact on surface analysis, and aspects of wearing-off by circulation are briefly discussed. 相似文献
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Latham MC 《Africa today》1993,40(3):39-53
Issues surrounding the spread of acquired immunodeficiency syndrome (AIDS) in Africa are summarized. Subjects considered include the disease's origins, proportion of the population infected with the human immunodeficiency virus (HIV) and AIDS, the problems in caring for children orphaned by the disease, innovations in drug treatments discovered by African scientists, the spread among women, and the difficulties inherent in incorporating Western-based policy and aid provisions into the African context. 相似文献
104.
C. ORTON 《Archaeometry》1993,35(2):169-184
This paper reviews the ways in which assemblages of pottery have been quantified throughout the twentieth century, and the use to which such data have been put. The values of various ways of quantifying pottery are compared, and a theoretical basis for the comparison of assemblages is described. Finally, the practical steps that need to be taken to make best use of the theory are set out. 相似文献
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The Reagan/Bush Administrations cut back federal support for state and local governments during the 1980s, causing total real resources available to finance local roads and bridges to increase very slowly between 1977 and 1989. The effect of federal aid on spending for infrastructure has been subject to debate for many years. Some studies have indicated that federal aid is stimulative, while others report that federal aid substitutes for local resources. This article examines the effect of state and federal aid on county highway spending. The analysis demonstrates that, in 1987, federal aid was stimulative but state aid was not. In light of changes brought about by the Surface Transportation Efficiency Act of 1991 (ISTEA), we can expect federal aid to have a stronger relationship with local highway spending. 相似文献
108.
Marla C. Berns 《African Archaeological Review》1993,11(1):129-148
Women dominate the production of pottery in Africa, yet few scholars have considered women the likely creators of the figurative ceramic sculpture recovered archaeologically across the savanna. Indeed, the question of who made these highly celebrated ceramics is rarely raised. A close look at the art historical and archaeological literature exposes the gender biases that privilege men's high art over women's low craft, making men the presumed creators of these works. Examples of women's predominance in the production of ritually-destined figurative ceramics in Nigeria alone counters such unsubstantiated assumptions. Through such production women play important roles in the construction of social and cultural meanings. It does make a difference in our reading and writing of history to understand and reconstruct what women make as well as what men make.
Résumé Les femmes dominent la production d'objets en argile en Afrique, mais peu d'experts ont considéré les femmes comme créatrices probables des sculptures figuratives en céramique découvertes dans des fouilles archéologiques dans toute la savane. De fait, la question de savoir qui fabriquait ces céramiques hautement prisées est rarement soulevée. Une étude plus approfondie de la littérature ayant trait à l'histoire de l'art et à l'archéologie met en évidence les partis pris sexuels qui privilégient l'art élevé des hommes par rapport à l'artisanat vulgaire des femmes, faisant des hommes les créateurs présumés de ces oeuvres. Des exemples de la prédominance des femmes dans la production de figurines rituelles en céramique au Nigéria contredisent ces suppositions non prouvées. Par cette production, les femmes jouent un rôle important dans l'élaboration de notions sociales et culturelles. Comprendre et reconstruire ce que font les femmes, de même que ce que font les hommes, nous fait lire et écrire l'histoire différemment.相似文献
109.
In skeletons excavated from Woodland sites, copper and barium levels are found to have been contaminated by influx from the soil environment. Electron microprobe scans for both elements show build-up along the outer surface of femur cross sections. Elemental levels for Cu and Ba are lower in the femur or fibula than in the more porous rib. The distribution of Cu in the immediately surrounding soil is highly anisotropic. These observations indicate that Cu and Ba should not be used for dietary inferences about ancient populations without independent evidence that diagenesis is not important. 相似文献
110.