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31.
Seventy-five teeth from the Bronze Age cemetery of Ya'amoun were sampled for carbon isotope analysis. The sampled teeth represented the transitional period of the Middle/Late Bronze Age. The results showed that the components of the diet that are reflected in the carbon isotope data remained the same during this period with an average δ13C of about −11.87‰. This value reflects more C3 plant consumption.  相似文献   
32.
The remains of the Kwäd?y Dän Ts'ìnch? individual, a frozen male human, were recovered from a retreating glacier within the Tatshenshini-Alsek Park in British Columbia in August 1999. In order to provide information on both the geographical origin of this individual and low long he spent in the remote interior region prior to his death, molecular analysis and compound-specific carbon isotope analyses were performed on individual amino acids purified from his skin and bone. Gas chromatographic quantification of constituent amino acids of both tissues revealed a molecular distribution characteristic of collagen, dominated by glycine and to a lesser extent proline, hydroxyproline and alanine. Chiral gas chromatography indicated that protein preservation in both tissues was exceptional. Carbon isotope analysis of a faunal assemblage from an earlier prehistoric site from southern British Columbia provided reference dietary amino acid δ13C values for terrestrial (deer and domestic dog) and marine species (salmon and sealion), showing clear separation in all amino acids, particularly glycine which was extremely 13C-enriched in the marine animals. The distinction between terrestrial and marine organisms was increased by exploring Δ13CGlycine-Phenylalanine values (6.6 ± 0.6‰ and 15.0 ± 2.1‰, respectively), which were higher in the latter by approximately 8‰, mirroring the increased δ15NBulk collagen values observed for the marine animals (R2 = 0.78; p < 0.001). The Kwäd?y Dän Ts'ìnch? individual's bone had a similarly elevated Δ13CGlycine-Phenylalanine value of 15.6 ± 1.0‰, indicating his extreme reliance on marine dietary resources throughout early life. The skin amino acid δ13C values were consistently lower than those observed for bone, with a concurrently lower Δ13CGlycine-Phenylalanine value of 12.7 ± 0.9‰. The shift between the carbon isotope composition of bone (long-term diet) and skin amino acids (short-term diet) confirmed a sudden divergence away from marine food sources in the last months of life, consistent with his discovery 80 km inland.  相似文献   
33.
In this study we examine the effects of alkaline cooking on carbon and oxygen stable isotopic ratios of mineralized tissues from nine pigs raised on monotonous mixed C3/C4 vegetarian diets. Two sources of collagen (humerus and mandible) and two sources of apatite (humerus and enamel) were analyzed. Within each diet group, humerus and mandible collagens were found to record equivalent δ13C and δ18O ratios; however, enamel apatite was found to be enriched over bone apatite by 2.3‰ in carbon and 1.7‰ in oxygen. Alkaline cooking was found to slightly, but significantly increase the Δ13Ccollagen-diet and Δ18Ocollagen-diet of bone collagen. A similar trend towards enrichment was observed in bone and enamel Δ13Capatite-diet and Δ18O apatite-diet, but the differences were not significant. Observed isotopic shifts were consistent with increased nutrient utilization of the alkaline-cooked maize as compared to raw maize. In addition, a reexamination of the relationship between diet and tissue carbon isotopic values suggests that species and alimentary type should be considered when interpreting ancient diets.  相似文献   
34.
为全面了解秦始皇帝陵园出土青铜水禽表面彩绘装饰工艺的技术内涵,利用显微观察、偏光显微鉴定、拉曼光谱分析等手段,对秦始皇帝陵园K0007陪葬坑出土彩绘青铜水禽表面彩绘装饰工艺进行了系统的考察和研究。研究结果显示,白色颜料为骨白,黑色颜料为炭黑;彩绘层为多层绘制而成,在结构上与秦陵出土陶俑、陶马表面彩绘具有明显区别;彩绘绘制技法包括平涂及堆绘两种,其中堆绘主要用于羽毛纹路羽轴的绘制,施彩工具可能为毛笔或毛刷。彩绘作为青铜器的装饰工艺主要出现于秦汉时期,但并没有得到广泛应用,可能与彩绘装饰自身的脆弱性以及青铜器的功能由礼容器转变为实用器有关。  相似文献   
35.
Stable isotope analyses have been applied to human and faunal bone collagen from the Varna I and Durankulak cemeteries to explore palaeodietary adaptations in the Neolithic and Eneolithic (Copper Age). The results suggest both populations primarily utilised terrestrial, C3-based diets, despite their proximity to the Black Sea. The wider δ15N range of the Durankulak humans likely indicates the differential utilisation of terrestrial meat sources, which is probably related to the degree to which primary and/or secondary ovicaprid products were consumed, particularly since ovicaprid δ15N values differ from other herbivores. The isotopic distribution of Varna I reflects a linear relationship between δ15N and δ13C, suggesting that a minority of individuals enriched in both isotopic parameters supplemented their diets with marine resources. These burials include the well known ‘chieftain’ (burial 43) and show notable material wealth by way of grave goods. At the population level, however, there is no significant correlation between stable isotope values and material wealth at Varna I, a fact with implications for theories regarding emergent social/economic hierarchies in Balkan prehistory. Five burials at Durankulak were found to have relatively enriched δ13C and δ15N values with respect to the rest of the population. These burials reflect a prominently marine-based or mixed terrestrial C3-based diet that included C4 inputs, possibly from millet, for which the limitations of stable isotope analysis on bulk collagen are not able to differentiate. AMS dating has shown that these burials belong to a much later period.  相似文献   
36.
We analyzed stable carbon and nitrogen isotope ratios of human and animal remains from the Ando shell midden, South Korea. The Ando site is a rare Incipient Chulmun (Neolithic) site (ca. 6000–5000 BC), which contains well-preserved human and animal bones in shell mounds. The stable isotope results for humans (average δ13C = −13.5 ± 0.5‰ and δ15N = 15.2 ± 0.5‰) indicate that Ando people in the Incipient Chulmun period strongly depended on marine resources. There were no isotopic differences between humans of different sex and age at this site. We compared our data with other previous published isotopic data from the Chulmun sites and found that the Ando people had similar isotope values to the southern Chulmun people (Tongsamdong and Daepo), but different isotopic ratios than the western Chulmun people (Daejukri and Konamri). These results indicate that marine foods were the main food resources in the southern coastal regions, but not in the western coastal regions in Chulmun Korea.  相似文献   
37.
Between the 13th and 11th centuries BCE, most Greek Bronze Age Palatial centers were destroyed and/or abandoned. The following centuries were typified by low population levels. Data from oxygen-isotope speleothems, stable carbon isotopes, alkenone-derived sea surface temperatures, and changes in warm-species dinocysts and formanifera in the Mediterranean indicate that the Early Iron Age was more arid than the preceding Bronze Age. A sharp increase in Northern Hemisphere temperatures preceded the collapse of Palatial centers, a sharp decrease occurred during their abandonment. Mediterranean Sea surface temperatures cooled rapidly during the Late Bronze Age, limiting freshwater flux into the atmosphere and thus reducing precipitation over land. These climatic changes could have affected Palatial centers that were dependent upon high levels of agricultural productivity. Declines in agricultural production would have made higher-density populations in Palatial centers unsustainable. The ‘Greek Dark Ages’ that followed occurred during prolonged arid conditions that lasted until the Roman Warm Period.  相似文献   
38.

Racialist social agendas have helped determine who will and will not be admitted to the engineering programs of American universities, and bench‐level activities within university laboratories have both followed from, and encouraged these structures of occupational opportunity. The engineering division of Iowa State College between 1900 and 1960 was one site of such exclusionary activity. African‐American students were under‐represented in its programs throughout this period, even as other areas of the university diversified and as women gradually increased their presence in the engineering division. This paper proposes a study of ISC's engineering curricula, instruments, and facilities as a means of identifying and understanding this inequity.  相似文献   
39.
This study investigates the relationship between diet and cultural change in late Iron Age and Romano-British populations from Dorset, England (1st century BC to the early 5th century AD). Dorset was the only region in Britain to exhibit continuity in inhumation burial rites through these periods and a wide array of environmental, archaeological and material culture evidence is available there. A sample of N = 77 human adult and N = 17 faunal rib samples were utilized for carbon and nitrogen stable isotope analysis to test the hypothesis that Romanization of the diet would result in greater dietary variation.  相似文献   
40.
Isotopic analysis of domestic turkey (Meleagris gallopavo) bones from Shields Pueblo, southwest Colorado, USA, suggests that these birds consumed a diet high in C4 plants. This contrasts with the diet of local herbivores, where much lower percentages of C4 plants were recorded. In view of the prevalence of maize (Zea mays) in the human diet of Ancestral Puebloan people, we suggest that turkeys were fed food scraps and surplus maize, rather than being allowed to forage for themselves. This suggests that turkeys were carefully tended in the household. Analysis of specimens from other sites in the northern Southwest shows that this pattern of turkey feeding characterizes all of the sampled horticultural communities.  相似文献   
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