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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   
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The US–ROK alliance during the First Korean Nuclear Crisis provides the most likely case of high alliance cohesion. Curiously, however, instead of dancing to the American tune in their joint management of the Democratic People's Republic of Korea (DPRK) threat, the Republic of Korea (ROK) caused frequent policy collisions – supporting the US–DPRK negotiations at one point and opposing it at another – at the risk of jeopardizing its physical security. The main finding here is that the variations in the South Korean behavior were a function of their experience of status inconsistency. In particular, the ROK became compliant with the US–DPRK talks when it believed that its desired status marker of taking the leadership role in crisis management was within reach, and unyielding otherwise. These fluctuations ended up not only eroding the US–ROK alliance cohesion but also inhibiting a successful resolution of the crisis. All this bears directly on the fundamental question of whether international politics is to be understood in essentially realist terms.  相似文献   
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Wang, Q., Wang, Y., Qi, Y., Wang, X., Choh, S.J., Lee, D.C. & Lee, D.J., November 2017. Yeongwol and the Carboniferous–Permian boundary in South Korea. Alcheringa 42, 245–258. ISSN 0311-5518

Six conodont and one fusuline zones are recognized on basis of a total of 25 conodont and 13 fusuline species (including seven unidentified species or species given with cf. or aff. in total) from the Bamchi Formation, Yeongwol, Korea. The conodont zones include the Streptognathodus bellus, S. isolatus, S. cristellaris, S. sigmoidalis, S. fusus and S. barskovi zones in ascending order, which can be correlated with the conodont zones spanning the uppermost Gzhelian to Asselian Age of the Permian globally. The fusuline zone is named the Rugosofusulina complicata–Pseudoschwagerina paraborealis zone. The co-occurrence of the conodont Streptognathodus isolatus (the Global Boundary Stratotype Section and Point index for the base of Permian) and Pseudoschwagerina (a Permian inflated fusuline) indicates that the Carboniferous–Permian boundary can be placed in the lower part of the Bamchi Formation in South Korea.

Qiulai Wang* [] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yue Wang* [] LPS, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yuping Qi* [] Xiangdong Wang* [] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Suk-Joo Choh [] Department of Earth and Environmental Sciences, Korea University, Seoul 02841, Republic of Korea; Dong-Chan Lee [] Department of Earth Sciences Education, Chungbuk National University, Cheongju 28644, Republic of Korea; Dong-Jin Lee [] Department of Earth and Environmental Sciences, Andong National University, Andong 36729, Republic of Korea. *Also affiliated with: University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, PR China.  相似文献   

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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   
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洪武年间,湖广各府级中心城治、西南少数民族等"寇乱"为患地区率皆设立卫所、筑城守御,并辅以巡检司、土司等多重防御力量。在其障护之下,腹里州县安全无虞,实无修固城防之必要。自洪武朝以至宣德朝,湖广地区修筑、维护城池主要限于驻军各地,对于其他众多普通州县并未从严要求,各地不修城的情形相当普遍。正是洪武朝奠定的颇为严密的区域安全防御体系保障了地方安定,为明前期实行这种相对宽松的筑城政策创造了条件。一些学者所谓明代"一贯积极、严厉的"筑城政策似乎并不完全切合明前期的实际。  相似文献   
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