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21.
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.
ABSTRACT

The 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.
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.
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   
26.
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   
27.
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   
28.
张芳 《文博》2015,(3):95-97,109
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   
29.
清末围绕立宪法、开国会而展开的“预备立宪”,是中国历史上亘古未有的一场从帝制向宪政过渡的社会革命.同所有改革一样,它需要全社会付出时间和努力加以培育,方可使其逐渐臻于完善.但不管是各省的国会请愿运动还是作为预备国会资政院的速开国会议案讨论,都在先进国家成功的示范和本国危亡的压力下获得空前的社会认同,将上自清廷权贵下至各省士民卷入其中,并使带有激进色彩的“速开”论思潮产生广泛社会影响.回顾资政院速开国会案讨论过程乃至整个国会请愿运动,除了让人振奋于中国民众空前的权利诉求之外,也不难发现运动中激进思潮的愈演愈烈,进而表现出人们对国会制度的多重误读,并由此产生诸多负面的效果.  相似文献   
30.
李晶 《安徽史学》2015,(3):115-122
19世纪后半期迅猛发展的美国城市化,使美国社会经济生活出现全方位的变化。同时,人口高度密集的城市环境导致公共卫生问题恶化,出现所谓的卫生危机,从而促发了城市公共卫生改革。此后,在美国城市的环境治理和疫病防治方面都出现系列性变化,城市公共卫生开始走上正轨。在此过程中,政府开始直接干预公共卫生,大众卫生意识得以强化,为美国城市卫生事业留下了宝贵遗产。  相似文献   
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