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21.
Dysentery was a significant cause of ill health during medieval times according to written sources of the period. However, it has been very difficult to detect the organisms that cause dysentery in archaeological samples from latrines and cesspools. This is because the cysts of the enteric parasites that cause dysentery are very small and usually fragment in the soil, in contrast to the robust ova of parasitic intestinal worms. This study uses a monoclonal enzyme-linked immunosorbent assay (ELISA) technique to identify the fragments of those enteric parasites that cause diarrhoea. Samples were taken from two excavated medieval latrines in the city of Acre. Coins and radiocarbon dating suggest that the latrines were in use during the thirteenth century CE. Positive results were noted for Entamoeba histolytica and Giardia duodenalis, while Cryptosporidium parvum was negative. This is the first time that either of these parasites have been identified in the Middle East using these methods. 相似文献
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Abstract. This paper examines the initial location choice of legal employment‐based immigrants to the United States using Immigration and Naturalization Service data on individual immigrants, as well as economic, demographic, and social data to characterize the 298 metropolitan areas we define as the universal choice set. Focusing on interactions between place characteristics and immigrant characteristics, we provide multinomial logit model estimates for the location choices of about 38,000 employment‐based immigrants to the United States in 1995, focusing on the top 10 source countries. We find that, as groups, immigrants from nearly all countries are attracted to large cities with superior climates, and to cities with relatively well‐educated adults and high wages. We also find evidence that employment‐based immigrants tend to choose cities where there are relatively few immigrants of nationalities other than their own. However, when we introduce interaction terms to account for the sociodemographic characteristics of the individual immigrants, we find that the estimated effects of location destination factors can reverse as one takes account of the age, gender, marital status, and previous occupation of the immigrants. 相似文献
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J. Buxeda I Garrigs R. E. Jones V. Kilikoglou S. T. Levi Y. Maniatis J. Mitchell L. Vagnetti K. A. Wardle S. Andreou 《Archaeometry》2003,45(2):263-284
The study of technology transfer in pottery production to the periphery of the Mycenaean world has been addressed by considering two different areas, southern Italy and central Macedonia. Technological features such as ceramic paste, decoration and firing have been determined for different ceramic groups established according to provenance criteria. The studies of technology and provenance have been performed following an archaeometric approach, using neutron activation analysis, petrographic analysis, X‐ray diffraction and scanning electron microscopy. The results have revealed the existence of two different models. On the one hand, southern Italy seems to exhibit a more organized pottery production, which follows a Mycenaean‐like technology, while in central Macedonia production is probably more varied, being based in part on the technology of the local tradition. 相似文献