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Júlio Cesar. de A. Marsola Gerald Grellet-Tinner Felipe C. Montefeltro Juliana M. Sayão Annie Schmaltz Hsiou Max C. Langer 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):563-567
Marsola, J.C.A., Grellet-Tinner, G., Montefeltro, F.C., Sayão, J.M., Hsiou, A.S. & Langer, M.C., 2014. The first fossil avian egg from Brazil. Alcheringa 38, 563–567. ISSN 0311-5518.In contrast to the rich record of eggs from non-avian dinosaurs, complete eggs attributable to Mesozoic birds are relatively scarce. Nevertheless, several well-preserved specimens have been discovered over the last three decades revealing functional and phylogenetic characters that shed light on the breeding strategies of extinct birds. Here we report the first fossil avian egg from Brazil, which was discovered in Upper Cretaceous strata of São Paulo in the southeastern part of the country. The taxonomic identity and structural features of the biomineralized tissues were determined using a combination of Scanning Electron Microscopy, Wave Dispersion Energy analyses and Computed Tomography. These show that the 125.5-μm-thick shell of the 31.4?×?19.5?mm egg incorporates three structural layers of similar thickness with both prismatic and aprismatic boundaries. Close similarity between the Brazilian bird egg and those of enantiornithines from the Upper Cretaceous Bajo de la Carpa Formation (Río Colorado Subgroup) of Argentina advocates affinity with basal Ornithothoraces. Furthermore, coherency of their depositional contexts might imply a compatible preference for breeding and nesting environments.Júlio Cesar de A. Marsola [juliomarsola@gmail. com], Annie Schmaltz Hsiou [anniehsiou@ffclrp. usp. br] and Max C. Langer [mclanger@ffclrp. usp. br], Laboratório de Paleontologia de Ribeirão Preto, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, São Paulo state, 14040-901, Brazil. Gerald Grellet-Tinner [locarnolugano@gmail. com], Centro Regional de Investigaciones La Rioja—Consejo Nacional de Investigaciones Científicas y Técnicas, Entre Ríos y Mendoza s/n, 5301 Anillaco, Argentina; Orcas Island Museum, PO Box 134, 181 North Beach Road, Eastsound, WA 98245. Felipe C. Montefeltro [felipecmontefeltro@gmail. com], Departamento de Zoologia, Universidade Estadual Paulista, Avenida 24A 1515, Rio Claro, São Paulo State, 13506-900, Brazil. Juliana M. Sayão [jmsayao@gmail. com], Laboratório de Diversidade do Nordeste, Núcleo de Biologia, Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, Rua do Alto do Reservatório s/n, Bela Vista, Vitória de Santo Antão, Pernambuco state, 52050-480, Brazil. Received 18.12.2013; revised 30.4.2014; accepted 18.5.2014. 相似文献
123.
《Journal of Modern Chinese History》2013,7(1):33-43
Russian populism spread in China at the turn of the twentieth century in the name of anarchism, nihilism, and socialism, and gradually contributed to the formation of modern Chinese populism. Populism around the time of the 1911 Revolution had two characteristics: one was its deep hatred of capitalism which regarded capitalism as an ugly, decadent, and regressive historical phenomenon; the other characteristic was an attempt to get around the developmental stage of capitalism in order to proceed directly into socialism. Compared with Russian populism, modern Chinese populism did not have well-organized proponents, nor did it have any systemic system of populist political thought. It manifested itself more as a populist intellectual tendency without a strong self-awareness. Agrarian civilization and Confucianism provided the hotbed for populism, and a superficial understanding of Western capitalism was the main cultural drive that bred populism. The most important feature of modern Chinese populism was the fantasy of leaping from a backward agrarian country into socialism by surpassing capitalist industrialization. 相似文献
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Regarding illicit drugs as a nontraditional security challenge (NTS), the Chinese state deploys a policy package combining coercive crackdown and development assistance to start transnational narcotics control in the Golden Triangle—the notorious illicit opium-producing area between Myanmar, Laos, and Thailand. This paper examines how illicit drugs are framed as a security challenge and how the state works with other forces to implement transnational narcotics control. Specifically, I focus on the Chinese state's efforts to implement transnational narcotics control in the notorious illicit opium-producing areas in northern Laos and Myanmar. My analysis draws first on the Copenhagen School's work on securitization, that is, how certain discourses are deployed to dramatize and present an issue as a security challenge requiring supreme priority. Then I situate drug trafficking in the tension between the territorial logic of national sovereignty and the transnational logic of NTS challenges in order to analyze the Chinese state's policy of narcotics control in the Golden Triangle. Through this analysis, I seek to underscore the longstanding but underdeveloped theoretical recognition of illicit drugs as a global commodity and an NTS challenge. The nexus of territorial sovereignty and extraterritorial subsystems spells out a new direction to understand NTS challenges in general and illicit drugs in particular. 相似文献
126.
黄河中下游地区40余处遗址的400多座二层台墓资料显示,生土二层台墓的数量在仰韶中晚期以前较熟土台墓多,龙山时代式微。该变化的背后是棺椁的逐渐成熟,生土台墓中小部分带有盖板或原始棺椁,同时熟土台并非判断墓葬带有棺椁的充要条件。通过生土台高度和墓葬深度的二元变量分析,墓葬开挖时预留生土台并未考虑稳固墓室,而应该与构建殓尸空间(或椁室)、进行一系列丧葬活动有关,在台面上放置随葬品的情况存在一定的时空差异。二层台墓的分布具有集中埋葬的倾向,采用二层台墓的群体并无明显的性别和死亡年龄指向,从仰韶中期以来,其所代表的社会群体占据着更为优越的社会财富。 相似文献
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刘雅媛 《中国历史地理论丛》2020,(1):92-102
学界对于传统中国城市空间近代转型相对缺乏关注.通过对上海县城的研究发现,在人口压力增加、城市用地紧张、环境恶化及租界示范效应的多重作用下,明清治所城市空间结构不再适用于20世纪初的上海县城,城市空间亟待改造.上海县城市政机构的设立为解决这一需求提供了制度保障与财力支持,故县城得以开展前所未有的大规模建设,包括道路、排水... 相似文献
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夏增民 《中国历史地理论丛》2020,(2):76-86
在明代,由于水患频发和长江主泓变动等原因,湖广武昌府城沿江江岸屡屡崩陷,当地政府遂启动江岸修筑工程.考诸史志,明代武昌府城的江岸修筑主要约有四次,分别是正统七年(1442)、成化三年(1467)、万历十七年(1589)和万历三十四年(1606).最终修成的江岸,自武昌府城南门望山门外(今武昌解放路南端解放桥附近)起,向... 相似文献
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龙小峰 《中国历史地理论丛》2020,(2):95-109
20世纪50年代初期,以民族为名称的各层级自治区非均衡地建立,致使政府在已建立民族区域自治的地区与尚未建立区域自治的民族地区执行经济政策时出现偏差,经济政策偏差产生的优惠差异引发了都安瑶族群众谋求民族区域自治的问题.为了解决瑶族谋求民族区域自治问题,在采取经济政策调整和相应政治措施调整无果之后,为配合民族区域自治政策的... 相似文献
130.
李成 《中国历史地理论丛》2020,(3):69-79
明嘉靖四十二年(1563),割黄冈、麻城、黄陂三县之地设黄安县.新县设置是朝廷“量地置邑”的结果,黄安建县缘起地方盗匪难靖,其实质不外乎朝廷加强统治的举措.但黄安县的设置又与他邑有所不同,是由以地方士绅为中心的地方势力自下而上呈请设置.新县设置处于朝廷党派斗争的政治背景下,存在着一定的偶然性,但通过建县,呈现出的是地方... 相似文献