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991.
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993.
Dykstra RR 《美国史评论》2003,31(4):554-563
994.
Robert J. C. Mowat 《International Journal of Nautical Archaeology》2020,49(1):222-223
995.
996.
The social safety net in the United States consists of a variety of programs administered by both federal and state governments. Although the populations served by social programs such as Medicaid and consumer bankruptcy likely overlap, policymakers tend to look at individual programs unilaterally and often fail to communicate appropriately with legislators and political leaders at differing levels of government. The result of such an incremental approach to policy reform is a fragmented social safety net system in the United States. In this study, the relationship between two social programs belonging to the larger social safety net is examined, and recommendations for policymakers are offered. 相似文献
997.
Archaeological samples of human and faunal remains dating from the Viking (9–11th century AD) and Early Christian (11–12th century AD) periods of Gotland, Sweden were assayed through stable carbon and nitrogen isotope analysis in order to investigate whether changes in subsistence occurred between these periods, particularly regarding the importance of seafood. The study was concerned with how the dietary regime of the Baltic trading port and farming settlement at Ridanäs, Gotland was affected by the widespread environmental and sociocultural transformations that characterized the end of the Viking Age. More generally, the research considers how changes in both food procurement and preference may account for observed differences in the dietary regimes of individuals from the Viking Age and the Early Christian period. 相似文献
998.
Feasts provide a public forum where social statuses can be affirmed or challenged among pre-state societies. Documenting feasting behavior thus provides insight into the construction of prehistoric political power. This paper presents expected material patterns of feasting by focusing on intra-site variability in food preparation, presentation, and consumption. Expectations are evaluated by comparing ceramic, ground stone, obsidian, and faunal data recovered from Conchas phase (900–800 BCE) elite and village midden deposits at Cuauhtémoc in the Soconusco region of southern Mexico. I argue that elite feasting at Cuauhtémoc created political cohesion between elite and non-elite segments of society during the Conchas phase as a new polity emerged that was more socially stratified and politically hierarchical than anything previously known in the region. 相似文献
999.
Jennifer A. Leonard Orin Shanks Michael Hofreiter Eva Kreuz Larry Hodges Walt Ream Robert K. Wayne Robert C. Fleischer 《Journal of archaeological science》2007
Molecular archaeology brings the tools of molecular biology to bear on fundamental questions in archaeology, anthropology, evolution, and ecology. Ancient DNA research is becoming widespread as evolutionary biologists and archaeologists discover the power of the polymerase chain reaction (PCR) to amplify DNA from ancient plant and animal remains. However, the extraordinary susceptibility of PCR to contamination by extraneous DNA is not widely appreciated. We report the independent observation of DNA from domestic animals in PCR reagents and ancient samples in four separate laboratories. Since PCR conditions used in ancient DNA analyses are extremely sensitive, very low concentrations of contaminating DNA can cause false positives. Previously unidentified animal DNA in reagents can confound ancient DNA research on certain domestic animals, especially cows, pigs, and chickens. 相似文献
1000.
Sulphur isotopes in archaeological bone collagen are not routinely analysed in palaeodietary studies. Here we investigate the potential contribution that sulphur isotope analysis can provide toward the study of ancient human diet and economy, with particular emphasis on the distinction between freshwater and terrestrial consumers. For material from the Late Bronze Age site of Chicha in the south-western Eurasian forest-steppe, sulphur isotopes effectively separate freshwater and terrestrial animal food resources. The sulphur isotope data coupled with nitrogen isotope values from Chicha reflect a dietary reliance upon freshwater animal protein (fish) for the Late Bronze Age inhabitants. In contrast, sulphur isotope values for freshwater and terrestrial potential food species from the Eneolithic site of Bil'shivtsi in western Ukraine were indistinguishable, demonstrating that δ34S values cannot always be relied upon to identify freshwater and terrestrial consumers. The data from this study support the adoption of δ34S analysis as a standard component of palaeodietary studies; apart from its potential to distinguish freshwater from terrestrial consumers, it can provide supplementary dietary information not evident from the carbon and nitrogen isotope data. In addition, certain indices are considered that may be used to assess the validity of sulphur isotope data, as currently exist for carbon and nitrogen. According to the analysis of modern collagen samples, N:S appears to be a broad indicator of collagen sulphur isotope quality. However, more work needs to be done to establish an effective means by which highly-altered sulphur isotope values can be identified and thereby removed from consideration. 相似文献