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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
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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.
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
23.
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
24.
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
25.
美国长期大量向日本出售钢铁、石油等战略物资,助长其侵华实力。1939年7月,蒋介石致电罗斯福,建议美国采取办法,削弱日本的战斗力与经济力。同月,美国政府宣布废止美日商约,对日实行经济制裁。1941年4月,日本向美国提出《日美谅解案》,企图通过谈判,减轻美国对日本的经济压力。罗斯福为避免美国过早陷入大西洋和太平洋同时两面作战的不利局面,提出退让、妥协方案,企图在一定时间内放松对日本的经济封锁。蒋介石坚决反对美国政府改变对日政策,愤而以"国际信义"与"人类道德"相责,胡适、宋子文也积极与美方交涉,最终,美国对日政策由有限度的妥协恢复为全面强硬,美日谈判破裂。日本指责美国已彻头彻尾地成为蒋介石的代言人,于12月初突袭珍珠港等地,太平洋战争爆发。 相似文献
26.
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
27.
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
28.
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
29.
罗马帝国初期的200年(公元前27年~公元2世纪)是罗马的鼎盛时期,开创了经济、文化、军事、艺术前所未有的高峰,被称为"罗马和平"时期。本文保护修复的几件"罗马和平"时期的石碑原本收藏在意大利罗维纳市的Lapidario博物馆,后委托意大利博洛尼亚KRITERION文物修复公司进行保护修复,进行了清洗、补全、封护等保护修复工作。 相似文献
30.
1924年英国大选期间发生了"季诺耶维夫信"事件,英国《每日邮报》在大选前四天发表了一封事后被证明是伪造的"季诺维也夫信"。然而,该信的发表在当时造成巨大影响,它对英国大选及工党政府的黯然下台、英国社会"红色恐怖"情绪的发展以及《英苏协定》的困难进程等事件都产生了重大的影响。 相似文献