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21.
An Approach to the Diagnosis of Craniofacial Fibrous Dysplasia from the 2500‐Year‐Old Remains of a Skull from Ancient China 下载免费PDF全文
K. L. Cheng H. Shao D. Zhao B. T. Sun J. Yu Z. C. Sun M. C. Li L. Guo H. Zhu Q. C. Zhang Y. H. Huang 《Archaeometry》2018,60(1):171-182
A human skull, buried about 2500 years ago in a Bronze Age cemetery at Jinggouzi, a site of an important ethnic group in ancient China, appeared to have characteristics of fibrous dysplasia. The CT images indicated a reduction in bone density and relatively homogeneous lesions. More features were revealed using CT reconstruction techniques. Lesions seen in low‐magnification images using a 3D deep‐field microscope had an irregular honeycomb‐like structure. At higher magnification, the trabeculae morphology and the gaps between the trabeculae were irregular and varied in size and shape. Paraffin‐embedded specimens stained with HE showed trabeculae with tortuous irregular arrangements varying in shape and width. The irregular trabeculae of woven bone has been described as having fibrous dysplasia. Molecular analysis of the GNAS gene indicated no mutation. This provides a non‐invasive approach for us to make more comprehensive diagnoses and to assist research into ancient human diseases. 相似文献
22.
由于多视角影像三维重建具有数据采集方便灵活、硬件成本低、操作简单、自动化程度高的特点,因此,选用多视角影像三维重建技术对张家界市博物馆明代铜佛像进行三维建模。通过描述佛像立面与空心底部的影像采集,再应用Agisoft PhotoScan软件进行三维重建的过程;从控制点的三维坐标与误差数值、模型成像与影像图的误差分析,得出佛像三维模型的精度误差微小的结论,证明该技术具有操作简单、模型成像清晰的特点。与三维激光扫描技术相比较,多视角影像三维重建技术具有成本费用低、工作流程高效简捷的优势,更适合在文物工作中推广运用。 相似文献
23.
ABSTRACTThe emerging problem of left-behind children has attracted mounting academic and policy attention. Prior studies primarily cast light on left-behind children’s education, health, and behavior, while their subjective well-being is much less understood yet. Based on a nationally representative sample of rural children aged 10–15 in 2014, we examine the impacts of different types of parental migration on children’s subjective well-being and how these affects vary between boys and girls. The results show that parental migration is a double-edged sword: children from both-parent migrant families report compromised life satisfaction and relationship quality compared with those in integral families, and mother-only migration significantly lowers children’s subjective health. On the flip side, father-only migration enhances children’s aspiration for attaining college, an encouraging effect that is even stronger than that of parental education and family income. These effects are heterogeneous by children’s gender: boys seem to be more susceptible to the disruptive effects of both-parent migration; mother-only migration effectively promotes girls’ educational aspiration while father-only migration promotes boys’. This study portrays a comprehensive image of left-behind children. Relaxation of hukou restriction, equal access to education, and revitalization of rural economies are imperative to improve the well-being of left-behind children.Abbreviations: LBC: Left-behing children; SWB: subjective well-being 相似文献
24.
正It is just the dawn,but the sheepfolds have already begun to move restlessly.Sunlight makes its way in.Tashi Tsedan and Redan open the sheepfolds one after another.Flocks of sheep suddenly gush out like an influx of water from an opened gate.These two herdsmen from Jirong Village in Drik Town of Gampa County are fulfilling their duty grazing these flocks of Gampa sheep,a well-known breed of Tibetan sheep. 相似文献
25.
Huo Wei 《中国西藏(英文版)》2018,(1)
正Ethnic people living on the Tibetan Plateau during the Tubo period have been well-known as not only strong and brave on horses,but they were also an ethnic group enriched with powerful creativity and rich imagination.From Tubo's cultural art,we can observe a large amount of extremely fine artifacts.For instance,among recently 相似文献
26.
Huo Wei 《中国西藏(英文版)》2018,(3)
正The cemetery of Tubo Tibetan Kings has always been well-known throughout history.It is situated upon a flat terrain on the right flank of Chongye river bank in Chongye County of Lhoka in the Tibet Autonomous Region.The length of the cemetery from the east to the west is about 相似文献
27.
张骏杰 《中国历史地理论丛》2020,(2):65-75,86
明显陵是嘉靖帝在湖广为其父母修建的陵墓。因显陵的肇建与扩建,承天府、兴都留守司、荆西道相继设立,显陵所在的监察区也得以改变。显陵政区及其相关都司卫所的变更过程,亦是显陵地区逐步脱离旧有政区层级,建立以显陵为核心的新政区层级的过程。相较于汉代迁移人口因陵设县,明王朝偏重于调整各级政区及其相关都司卫所的组合方式,以保障统治重地的物资人力供应和附近军民的集中统一管理。而明王朝以某地为中心进行一系列政区的变更,很有可能预示着某一区域内的统治重心发生了改变。 相似文献
28.
Nana Zhang 《Children's Geographies》2015,13(4):381-397
This article is centred on the geographies of Chinese children in contemporary China – an area which has been problematically overlooked in geographical literature on childhood. In employing unique mobile research methods by tracking migrant children through the migration cycle, the author conducted an extensive ethnographic study of rural migrant children aged 8–17 in China. The article explores rural children's everyday lived experience of migration and how migrant children negotiate and articulate home and belonging while on the move. The study demonstrates the dynamic environment that migrant children inhabit, the fluid, contextual and mobile nature of their life in rural migrant households, their migrancy and their active involvement in homemaking. 相似文献
29.
Cheng Lei Meng Hui Zhang Shi Qiang Fang 《International Journal of Architectural Heritage》2015,9(8):942-948
Ancient mortars played a crucial role in the construction of historical architectures due to their physical and chemical compatibility with traditional building materials such as stones and bricks. Therefore, the analysis and optimization of the ancient mortar formula are significant in the restoration and preservation of historical sites. In this work, 20 mortar samples selected from five ancient stone pagodas in Zhejiang Province, China, were analyzed. The results showed that mud, lime-soil mortar, lime-sand mortar, and lime-gypsum mortar were used as binders in these pagodas. The Ca(OH)2/aggregate ratio ranging from 0.3 to 2.7 was usually used to prepare lime mortar. Protein and polysaccharide were also found in some samples. 相似文献
30.
Wei She M. R. Jones Yunsheng Zhang Xing Shi 《International Journal of Architectural Heritage》2015,9(7):775-793
The Hui-style residence is an important architectural heritage of China. The hollow wall structures are widely used to build its exterior wall system. However, the thermal performance of the hollow wall is no longer able to meet the new energy-saving and environmental requirement. This article describes a laboratory study of the development of foamed mortar (FM), with the potential for use in thermal upgrading of the Hui-style hollow wall system without dramatically changing its traditional structure. The key early age, physical, mechanical and thermal properties were systematically measured. Two extended models were respectively developed to calculate compressive strength and thermal conductivity, as a function of porosity. Environment chamber test was also employed to investigate the effectiveness of this novel thermal upgrading approach and the results show that filling the voids with FM can effectively improve the overall thermal resistance of the hollow wall system by 44%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system. In addition, the combination of these two methods yielded an overall thermal resistance of 0.701 m2·K/W, which is even higher than 0.67 m2·K/W for the code required in the hot summer/cold winter climate zone. 相似文献