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The Southwest United States (US) and Mesoamerica are often thought of as disparate regional networks separated by Northern Mexico. Chaco Canyon in the Southwest US, Tlatelolco in Central Mexico and Casas Grandes in Northern Mexico, all had large inter‐regional trade centres that economically connected these networks. This study investigated how factors such as geographic distance, shared migration history, trade and political interaction affected biological relationships and population affinities among sites in Mexico and in Southwest US during the Postclassic period (ad 900 ~ 1520). Distances based on cultural and geographic variables derived from archaeological and ethnohistoric data were compared with phenetic distances obtained from dental morphological traits. The results of Mantel tests show trade (corr = 0.441, p = 0.005), shared migration history (corr = 0.496, p = 0.004) and geographic distance (corr = 0.304, p = 0.02) are significantly correlated with phenetic distances, whereas political interaction (corr = 0.157, p = 0.133) is not. Partial Mantel tests show trade (corr = 0.223, p = 0.049) and shared migration history (corr = 0.493, p = 0.003) remain significant when controlling for similarities with geographic distance, although the correlation for trade and phenetic distance is lowered. Geographic distance is not significant when similarities with trade (corr = 0.067, p = 0.681) and shared migration history (corr = 0.148, p = 0.127) are controlled. These results highlight the importance of economic relationships and shared migration history across geographic regions in interpreting biological relationships among contemporaneous populations in prehistoric Mexico and the Southwest US. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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This paper presents an assessment of all known dental and mandibular morphological criteria for differentiating sheep (Ovis aries) and goats (Capra hircus) using for the first time an archaeological sample of complete caprine skeletons (90 sheep and 13 goats) from burials at Kerma (Sudan, 3rd and 2nd millennia BC). The species determinations were assessed using cranial and post-cranial morphological criteria. Consequently, the reliability (percentage of correct determination) and efficiency (complementary percentage of intermediate scores i.e. neither sheep nor goat) of 38 individual dental criteria could be fully assessed using a prehistoric homogeneous domesticate population. We demonstrate that, for this sample, individual criteria for lacteal teeth are more reliable for sheep (sheep: 95 ± 3%) than the adult premolars (85 ± 5%) and molars (sheep: 88 ± 2%), whereas for goats premolar criteria were more reliable (83 ± 12%). For efficiency, lacteal dental criteria are better (goat: 97 ± 5%; sheep: 95 ± 3%) than those for premolar (goat: 85 ± 10%; sheep: 79 ± 5%) and molar (goat: 82 ± 6%; sheep: 83 ± 2). We also demonstrated that most isolated teeth can be determined with less than 10% error. However, on average, within specific age classes (0–1 year, 1–4 years and more than 4 years), isolated teeth increased in reliability and decreased in efficiency. The average reliability of the criteria for complete mandibles for each age class for goats and sheep was 100%, when the efficiency was 67, 40 and 50% for goats and over 90% for sheep. This is due to the effect of age on the efficiency of isolated criteria and the poor performance of specific criteria mainly those P3, M1 and M2. We conclude that separate species kill-off profiles are possible. The effect of age on dental criteria would not significantly change the interpretation for specific subsistence strategies focused on one particularly species.  相似文献   
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河南信阳城阳城遗址M8为高等级战国晚期楚国贵族墓,该墓出土了以漆木器为主的各类文物400余件,其中尤以黑、红两色竹蔑编织而成的髹漆竹席最为精美。为开展彩漆竹席脱水保护提供基础数据,采用激光共聚焦显微镜、拉曼分析仪和傅里叶红外吸收光谱仪(FTIR)及扫描电镜-能谱(SEM-EDS)等现代分析仪器对竹席漆膜的成分及表面形态进行了分析,并在此基础上,结合传统髹漆文献资料探讨了漆膜的制作工艺。结果表明:城阳城彩席中的黑色漆膜为大漆自然显色,红色漆膜是大漆掺加朱砂调制而成;黑色漆膜表面较为平整,漆膜与胎体结合紧密,红色漆膜表面相对粗糙,结构较为疏松;竹席漆膜的厚度在0.02~0.03 mm之间,应是由大漆涂刷至少3~5次制备而成。研究结果可为下一步的彩漆竹席的脱水保护及展示提供基础数据。  相似文献   
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作为人类文化遗产的重要组成部分,古旧木材保存状态的评价及保护至关重要。为了推进对古木材保存评价的深入研究,通过对多参数检测(微形态学、物理学、化学)在微观尺度下评价古旧木材保存状况及腐蚀机理的研究成果进行了综述,在介绍了从木材细胞形态、物理孔隙结构、化学组分含量、分子结构、分子量分布等方面对古旧木材进行评价的基础上,较为全面地阐述了检测各参数的不同表征方法,包括扫描电镜法、氮气吸附法、高效液相色谱法、气相色谱/质谱联用法等,具体分析了不同表征方法间的优缺点,说明了多参数检测古旧木材保存状况的可行性及重要性,并希望以此为切入点探讨古旧木材的宏观力学性能。研究结果在木质文化遗产和历史木构建筑的保护方面具有极大价值。  相似文献   
56.
华北平原农村居民点演变及社会经济影响因素分析   总被引:8,自引:0,他引:8  
杨勇  邓祥征  吴锋  陈彤 《人文地理》2019,34(2):116-124
基于遥感图像分类解译数据,利用位序-规模模型、洛伦兹曲线、景观指数,定量识别了2000-2015年华北平原农村居民点空间分布、规模与形态演变特征,分析了社会经济因素的驱动机制。结果表明:华北平原农村居民点南-北方向呈显著的空间分异与集聚特征,密度分布呈现南密北疏的态势,与面积规模分布存在局域负相关;农村居民点景观指数显示出密度增大、形状更加规则、斑块面积差异增大、斑块间邻近距离不断缩短的变化特征;总人口数量和乡村户数等对农村居民点用地扩张具有促进作用,乡村常住人口、乡村从业人员数量等的作用为负。  相似文献   
57.
Continental deposits of the Cullen Formation (early or middle Miocene) exposed on the northeast coast of Isla Grande de Tierra del Fuego (southernmost Patagonia) are analyzed. Twenty-four taxa of algae, and bryophyte and pteridophyte spores are identified, including three new species, which are Anthocerisporis gandolfii sp. nov., Coptospora archangelskyi sp. nov. and Ophioglossisporites cullensis sp. nov. Sedimentologic and palynological data suggest a system of meandering water channels. The diverse and abundant spore assemblage reinforces the proposed paleoenvironment indicated by pollen assemblage and stratigraphy, consisting of humid temperate forests and local occurrences of bog, freshwater and near-shore lake communities.  相似文献   
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针对突发灾害:大城市的人居安全及其政策   总被引:5,自引:1,他引:4  
非典事件折射出了大城市在应对突发灾害时抗灾能力低下的脆弱性以及严重的人居安全问题。大城市的人居安全问题与其规模、密度和形态的不协调有关。基于人居安全的城市政策应该是规模、密度、形态三位一体的城市政策。规模过大会引起安全问题,技术进步使人们解决城市问题的能力不断增强,因而城市规模的极限也不断被突破。但是,连续的、密集分布的城区终究不应该是无限放大的,从这点上看,城市形态的不佳将加重规模和密度过大所导致的问题。现阶段我国的城市政策几乎是不存在的,城市安全意识尚未发展成为全局性的"城市安全观",目前大城市的规模、形态、密度的失控是缺乏有效制约的市场力量作用的结果,规划失效的原因之一是没有清晰的城市政策,因而市政当局过分迁就开发商。新的城市政策对于大城市尤其要严格控制其密度,对城市提出明确的形态要求,制止城市蔓延,推进有组织的"都市区化"。  相似文献   
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The wolf is thought to have been abundant in many parts of medieval Europe, but its remains are rarely identified in archaeological contexts. One of the potential reasons for this is the problem of distinguishing between the skeletal elements of wolves and dogs, accentuated by poor preservation and fragmentation. This paper reviews the extent of this problem, exploring the morphological relationships between wolves and dogs, as well as the issue of hybridisation, and goes on to suggest how the scarcity of wolf remains may in fact reflect infrequent hunting. This is illustrated with a comparative regional case study of wolf hunting and commercial exploitation in medieval England and southern Scandinavia, synthesising archaeological and written sources. The paper concludes with an optimistic appraisal of the value of wolf remains in medieval archaeological contexts for a broader understanding of relations between humans and wolves in the medieval period. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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