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Zhaohui Pan Min Zhu You’An Zhu Liantao Jia 《Alcheringa: An Australasian Journal of Paleontology》2018,42(1):10-21
Pan, Z., Zhu, M., Zhu, Y. &; Jia, L., August 2017. A new antiarch placoderm from the Emsian (Early Devonian) of Wuding, Yunnan, China. Alcheringa 42, 10–21. ISSN 0311-5518.Wufengshania magniforaminis, a new genus and species of the Euantiarcha (Placodermi: Antiarcha), is described from the late Emsian (Early Devonian) of Wuding, Yunnan, southwestern China. The referred specimens were three-dimensionally preserved in black shales, allowing a high-resolution computed tomography reconstruction of anatomical details. The new euantiarch is characterized by a large orbital fenestra, an arched exoskeletal band around the orbital fenestra and a developed obtected nuchal area of the skull roof. Maximum parsimony analysis, using a revised data-set of antiarchs with 44 taxa and 66 characters, resolves Wufengshania gen. nov. as a member of the Bothriolepididae, which is characterized by the presence of the infraorbital sensory canal diverging on the lateral plate, and the nuchal plate with orbital facets. New analysis supports a sister group relationship between Dianolepis and the Bothriolepididae. Luquanolepis, a coeval euantiarch from the neighboring site of the new form, is referred to the Asterolepidoidei and represents the basalmost and earliest member of the Asterolepidoidei.Zhaohui Pan* [panzhaohui@ivpp. ac. cn], Min Zhu* [zhumin@ivpp. ac. cn], You’an Zhu? [zhuyouan@ivpp. ac. cn] and Liantao Jia [jialiantao@ivpp. ac. cn] Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, PR China. *Also affiliated with University of Chinese Academy of Sciences, Beijing, 100049, PR China. ?Also affiliated with Uppsala University, PO Box 256, 751 05 Uppsala, Sweden. 相似文献
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宛西自治:一场夭折的区域现代化实验 总被引:3,自引:0,他引:3
20世纪30—40年代,宛西地区发生了一场在“三自主义”指导下的区域性现代化实验。这场以追求“丰衣足食、安居乐业”为目标的实验.植根于本土化的基础之上,由于地理环境的独特和地方精英的努力而取得了一定的成绩;由于理论的局限和对封建土地制度的容忍,得不到广大贫苦群众的拥护而中途夭折。 相似文献
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In order to evaluate the seismic risk of transportation networks, it is necessary to develop a methodology that integrates the probabilities of occurrence of seismic events in a region, the vulnerability of the civil infrastructure, and the consequences of the seismic hazard to the society, environment, and economy. In this article, a framework for the time-variant seismic sustainability and risk assessment of highway bridge networks is presented. The sustainability of the network is quantified in terms of its social, environmental, and economic metrics. These include the expected downtime, expected energy waste and carbon dioxide emissions, and the expected loss. The methodology considers the probability of occurrence of a set of seismic scenarios that reflect the seismic activity of the region. The performance of network links is quantified based on individual bridge performance evaluated through fragility analyses. The sustainability and risk depend on the damage states of both the links and the bridges within the network following an earthquake scenario. The time-variation of the sustainability metrics and risk due to structural deterioration is identified. The approach is illustrated on a transportation network located in Alameda County, California. 相似文献
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历史语境中的王朝中国疆域概念辨析--以天下、四海、中国、疆域、版图为例 总被引:3,自引:1,他引:2
毕奥南 《中国边疆史地研究》2006,16(2):9-16
作为国家理念的体现,疆域概念产生于具体的历史语境。由于古今中国国家性质不同,王朝中国的疆域概念与现代中国主权、领土不能用简单的继承或对接来解释。在王权泛化或王权至上观念的影响下,王朝中国的疆域话语尽管受到地理知识限制,但仍坚持认为在可知范围内,王朝中国天子有权实行统治。这种深受王朝国家理念影响的疆域话语对古代疆域概念产生了很大影响。以常见的5个古代中国疆域概念为例,“天下”有广狭二义,一是普天之下,一是华夏诸国;“四海”即四方,有时包括四夷,有时不包括;“中国”概念迭加变化整合,各朝“中国”范围不尽相同;“疆域”是一国统治范围的宣示;“版图”则是王朝国家行政地区。本文通过追溯原本词义,认为上述概念原意与后世借用,因语境变化,语义发生差异;进而提出,学术用语与习惯说法应有区别,这不仅是运用概念准确与否的问题,而且也涉及研究价值的取向。 相似文献
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《五经正义》的颁行是唐代在经学文本上的统一举措。经学思想的真正统一还有赖于制度的保障。唐代教育、科举、铨选和其他相关制度不仅确保了五经的权威,而且极大地促进了经学的全面推广和传播。这些制度为经学统一提供了源头性的保障。 相似文献
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