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31.
Cutmarks have played an important role in addressing whether our hominid ancestors were hunters or scavengers, describing ritual modification of human bone, defining the origin of metallurgy, and highlighting the diversity of prehistoric butchering behavior. The widespread occurrence of cutmarks on animal bones and their variability allows archaeologists to use this kind of evidence to address a broad range of questions. One goal in examining cutmark diversity is to identify diagnostic cutmarks of prehistoric butchering, processing, and consuming behaviors. Linking cutmarks to specific activities allows us to test fine-grained hypotheses concerning the nature of an archaeological site, and to do this a systematic method for addressing variability in both the appearance and anatomical position of cutmarks is essential. An analysis of caribou bones collected by Lewis Binford from the Palangana site in Alaska is used to build and test a diagnostic cutmark classification using their morphometric and spatial properties. This case study demonstrates that cutmarks can be used to simultaneously address large-scale anthropological questions and reveal intra-site behavioral variability in the archaeological record.  相似文献   
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A study with wild lions in Tarangire National Park (Tanzania) and with captive lions in Cabárceno Reserve (Spain) has yielded two different bone modification patterns, probably as a result of the differences in environmental contexts. Captive lions have modified bones more intensively, both in the form of total number of tooth-marked bones and number of tooth marks per tooth-marked bone, probably because of stereotypic behaviors. This emphasizes the importance of environmental contexts to understand carnivore behavior and their resulting bone modification patterns. It also shows that analogical models based on experiments carried out with captive carnivores may be biased and inadequate as proxies for wild carnivore bone modification behaviors.  相似文献   
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Recent studies have shown that for many reinforced concrete lateral force-resisting elements (LFRE) stiffness is dependent on strength, and as a result strength assign-ment to these elements would affect both the strength and stiffness distributions in a structure. As a consequence, stiffness distribution cannot be considered known prior to strength assignment. This implies that in assigning strength to LFRE, the designer has the ability not only to prescribe the strength distribution, but also indirectly control the stiffness distribution in the structure. In this paper, a study is made on the seis-mic performance of a number of single-story structures to reconfirm that the “balanced CV-CR location” criterion, previously suggested by the writers, constitutes a desirable strength/stiffness distribution for minimising torsional response of asymmetric reinforced concrete structures.  相似文献   
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高分子彩绘类文物保护涂层材料的性能及应用研究   总被引:3,自引:1,他引:3  
针对彩绘类陶器保护的特殊要求,筛选性能优良的保护材料。在人工气候箱中对所选择的9种有机高分子文物保护涂层材料进行人工老化试验,分别采用傅立叶红外光谱仪测量试验材料的分子结构,分光光度仪测量颜料的主波长、色纯度和高度的变化,粘接强度仪测量颜料的粘接强度变化。结果表明:PrimalAC33、B72、有机硅的耐老化性能好,颜色变化小,粘接强度高,能很好的起到保护彩绘文物的作用,建议在文物保护领域推广使用。  相似文献   
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The examination of isotope ratios from multiple tissues offers new life to interpretations of commingled assemblages where information regarding individual biological history has been lost. Here, life histories from a commingled sample of Byzantine monks were reconstructed using enamel and bone δ13C and δ15N values. The δ13C values suggest a diet dominated by C3 products, while the δ15N ratios indicate variable contributions of animal protein. After correcting for tissue‐specific enrichment factors, bone δ13C values were significantly enriched over enamel; this may be due to an increase in protein consumption, but could also reflect structural differences between tissues or correction factors used to compare these data.  相似文献   
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Recent studies have emphasized the importance of Indigenous producers and traders in the formation of ethnographic museum collections, but have found difficulty in finding concrete evidence for their active roles. A use-wear and residue study of turtle bone cleavers from Wuvulu Island, Papua New Guinea provides the opportunity to test whether objects that comprise a significant component of early collections were made specifically for sale, as hypothesized by contemporary observers in the late 19th century. Comparative studies of used and unused turtle bone artifacts from the Caroline Islands and Papua New Guinea identified differences between wear traces resulting from manufacture and use. Analyses of the Wuvulu turtle bone cleavers showed they had been heavily used prior to sale. Rather than produce artifacts to meet the high demand from German traders, the local people sold old, worn-out objects, many of which had been repaired. The study demonstrates that archaeological approaches to ethnographic museum collections can trace Indigenous agency within cross-cultural interaction. It also showcases the potential of use-wear and residue analytical techniques for the analysis of bone tools and the utility of digital, hand-held microscopes for the analysis of large artifacts.  相似文献   
38.
We have investigated change in subsistence during the transition to agriculture in the site of Jiahu, Henan Province, China, using stable isotopic analysis of collagen and apatite in human bones. Millet agriculture is well documented at drier high latitudes of the Yellow River Valley, while rice agriculture predominated at wetter lower latitudes of the Yangtze Valley region. The early Neolithic site of Jiahu lies near the boundary between the drier north and wetter south. Archaeobotanical evidence shows that rice was a significant component of diet at Jiahu, but its δ13C value is similar to that of other foods, and therefore cannot be conclusively identified by carbon isotope analysis. Foxtail and broomcorn millets are the only C4 crops known for the Chinese Neolithic. Because of their high δ13C values, their consumption can be evaluated by stable carbon isotope analysis of human bone. Collagen reflects mainly the δ13C value of dietary protein, and apatite accurately records that of the whole diet. Isotopic analysis of 15 well-preserved samples from three periods shows that collagen δ13C values were very low for almost all individuals, suggesting C3-based foods dominated their diets. However, apatite carbonate δ13C values and δ13C spacing between collagen and apatite (Δ13Cap-co) indicate that millet may have been a minor component of the diet in this region. Individuals, who consumed the smallest amounts of animal protein, as indicated by low δ15N, generally had the highest apatite δ13C values. Archaeobotanical evidence for millet at Jiahu is needed to support this interpretation.  相似文献   
39.
A significant proportion of the Paris metro tunnels comprise a masonry vault built out of stone blocks and mortar joints, and sidewalls and slabs made of unreinforced concrete. In order to provide the necessary data for future structural evaluation, an extensive laboratory testing programme has been conducted to characterize the materials of the tunnel separately, i.e., mortar, stone, and concrete. The tests, carried out on specimens taken from cores extracted from a 1930s tunnel, enabled to determine the mechanical properties, including direct tensile, shear strength, and mode I fracture energy, as well as the properties of the stone-mortar interface. Results show that the masonry mortar joints could reach 10 cm in width, and that blocks of stone varied in composition and porosity, thus producing a wide range of mechanical properties. The concrete was composed of large-sized aggregates and showed low stiffness and strength. Based on these experimental results, ratios between mechanical characteristics are hereby proposed. Perspectives on the use of this experimental data in a finite element model are then discussed.  相似文献   
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