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31.
高颐阙是东汉晚期的红色砂岩的建筑物。位于四川省雅安市。阙檐东面残缺.导致日晒雨淋加剧,苔藓丛生,从而引起严重风化。为此,对残损阙檐进行了修复。根据高颐阙的结构.雅安市的气候特征及阙石的化学组成和物理性质.讨论了薄片检查和 X 衍射分析的结果、修复残缺阙檐的理论基础以及计算、修复的程序和效果。  相似文献   
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In the last decade, conversations around queering of GIScience emerged. Drawing on literature from feminist and queer critical GIS, with special attention to the under‐examined political economy of GIS, I suggest that the critical project of queering all of GIS, both GIScience and GISystems, requires not just recognition of the labour and lives of queers and research in geographies of sexualities. Based upon a queer feminist political economic critique and evidenced in my teaching critical GIS at two elite liberal arts colleges, I argue that the “status quo” between ESRI and geography as a field must be interrupted. Extending a critical GIS focus beyond data structures and data ethics, I argue that geographic researchers and instructors have a responsibility in queering our choice and production of software, algorithms, and code alike. I call this production and choice of democratic, accessible, and useful software by, for, and about the needs of its users, good enough software.  相似文献   
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P. Schmidt  A. Morala 《Archaeometry》2018,60(5):885-897
The earliest evidence of flint and chert heat treatment was found in the ~21.5–17 ka old European Solutrean culture. The appearance of pyrotechnology as part of the production of stone tools has important implications for our understanding of Upper Palaeolithic technological evolution and the specific adaptations during the last glacial maximum in Europe. However, the techniques and procedures used to heat‐treat rocks during the Solutrean remain poorly understood. No direct archaeological evidence has so far been found and the most promising approach is to understand these techniques by determining the parameters with which flint and chert were heated at that time. In this study, we investigate the heating temperature of 44 heat‐treated laurel‐leaf points from Laugerie‐Haute, using a non‐destructive technique based on infrared spectroscopy. Our results document that most of the artefacts were heated to a narrow interval of temperatures between 250 °C and 300 °C. This indicates a standardized technique that allowed to created similar conditions during successive heating cycles. The implications of these results for our understanding of the technical complexity during the Solutrean must be discussed in the light of different heating techniques used at different places and periods.  相似文献   
35.
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   
36.
Recent studies have shown that pre-Columbian societies in the Amazon undertook significant landscape modifications, including earthworks. Our fieldwork has revealed that pre-Columbian settlements in the Santarém Region, Lower Amazon, were not limited to the vicinities of permanent water courses, as formerly often assumed. Instead, numerous archaeological sites, dating from ca. a.d. 1300 up to the time of European colonization in the seventeenth century, have been found in an upland area known as the Belterra Plateau, south of the present-day city of Santarém. These upland sites have been found to be associated with particular features in the landscape: cavities or depressions, known locally as “Poços de Água”. LiDAR data shows that a pattern of non-randomly distributed depressions extends far into the densely forested Tapajós National Forest (Flona-Tapajós), allowing us to suggest that the expansion of inland settlement extended considerably farther to the south than what has previously been established through conventional archaeological fieldwork.  相似文献   
37.
It has been amply demonstrated that individuals' reproductive capability is the key explanatory phenomenon for understanding onomastic disappearance during the early modern period. This article analyzes the evolution and consequences of surname extinction in a specific population: Catalonia in the sixteenth and seventeenth centuries. In this article two aspects are examined. First, the observed disappearance of surnames is estimated through historical data collected in the Llibres d'Esposalles (Marriage Books) from 1481 to 1600 at Barcelona Cathedral. Second, the estimated natural extinction of those surnames registered in 1481 is forecast by applying a statistical branching process.  相似文献   
38.
A millennium ago in Northern Song (960–1127) China, Emperor Huizong initiated the “Eight Virtues of Conduct” in order to recruit morally upright officials. In place of the candidates’ skills in literary composition and understanding of the Confucian classics, this scheme adopted candidates’ moral virtues as their major criterion of selection. This paper analyzes how this scheme was implemented. It also shows that the rejection of certain genuinely virtuous nominees and the recruitment of some candidates who had exhibited objectionable conduct somehow compromised the emperor’s ideal. This analysis is followed by a discussion of the political and social implications of the scheme. Instead of perceiving this promotion channel as a means for Huizong and Chief Councilor Cai Jing to eliminate dissidents and install ideological conformity, the author argues that the scheme was an initiative of the emperor to counter the chief councilor’s dominance and alleviate factional conflicts. The final section examines the extent to which this scheme facilitated social mobility in the Song dynasty.  相似文献   
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During the Easter Offensive hundreds of Republic of Vietnam soldiers and civilians were killed while fleeing Qu?ng Tr? city along Highway One, earning this stretch of the road the name ‘the Highway of Horrors’ [??i L? Kinh Hoàng]. This article examines this understudied event and the efforts of ordinary people, particularly the staff of the daily newspaper Sóng Th?n, to collect and bury the corpses left on the highway. In focusing on this humanitarian endeavour, it highlights the spiritual consequences of mass death, people’s agency in countering the violence of the Vietnam War, and the dynamism of South Vietnam’s civil society.  相似文献   
40.
In 1934, Gabrielle Lévy died at the age of 48. She became well known for an article she published on a hereditary polyneuropathy in cooperation with Gustav Roussy, resulting in the eponym Roussy-Lévy syndrome. Not much is known about this extraordinary neurologist/neuropathologist. Her family declared that she died from the disease she was studying. She was a pupil of Pierre Marie, with whom she worked at the Salpêtrière in Paris and wrote on war neurology. In cooperation with Marie, she published a number of articles on postencephalitic syndromes, which also became the subject of her 1922 thesis. Three years later, she became associate physician at the Paul-Brousse Hospital in Paris, where the study of brain tumors became one of the subjects of her scientific work. Remarkably, Lévy was first author in a few of her many articles, although Roussy confirmed that she often initiated the study and even wrote the main part. In this article her career is considered in the context of the struggle of women physicians to improve their position during the early-twentieth century. She probably died from a brain tumor or a postencephalitic syndrome.  相似文献   
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