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91.
This article shares the first-time geographic information system (GIS) experiences of two advanced placement human geography classes. The teacher had participated in a summer GIS workshop and then brought those skills into her classroom for the students' benefit. Eighteen students shared their experiences researching their family history, working to map the migration of their genealogy to the United States, and presenting their findings to their classmates. Researchers were on hand to observe presentations and collected survey data from the students. Overall it was a very successful educational experience in which students utilized a “new” technology in the context of their own lives.  相似文献   
92.
四川省文博单位所藏大量可移动文物在5.12汶川地震中遭受不同程度损毁,其受损原因极具研究价值。采用文物受损信息调查表、实地调查与再核实、数据统计与分析等方法,针对受损可移动文物所处大环境、小环境及其存放或展示方式,结合每件可移动文物的受损状态进行统计研究。基本探明汶川地震中文博单位建筑和可移动文物受损原因和类型,为提升文博工作者的文物防震保护意识和开展文物防震保护研究提供基础资料。  相似文献   
93.
Sagasti, A.J., García Massini, J., Escapa, I.H., Guido, D.M. & Channing, A., August 2016. Millerocaulis zamunerae sp. nov. (Osmundaceae) from Jurassic geothermally influenced wetland environments of Patagonia, Argentina. Alcheringa 40, xxx–xxx. ISSN 0311-5518

A new species of Millerocaulis Erasmus ex. Tidwell emend. Vera is defined based on several permineralized stems recovered from geothermally influenced chert deposits in the Middle–Late Jurassic La Matilde Formation (Santa Cruz, Argentina). Millerocaulis zamunerae sp. nov. is characterized by the presence of an ectophloic dictyoxylic siphonostele, inner parenchymatic and outer sclerotic cortices, homogeneous sclerotic ring in the petiole bases, two masses of sclerenchyma lining the concavity of the petiolar vascular bundle, petiolar inner cortex with sclerenchyma strands in the outermost petiole cycles and stipular wings having one large and several smaller sclerenchyma bundles. Millerocaulis zamunerae inhabited geothermal wetlands and other hot-spring-related sedimentary facies associated with the La Bajada epithermal deposit. Reference to active geothermal wetlands, analogous living plants and other fossil hot spring ecosystems suggest the plant’s tolerance of physico-chemical stressors including elevated temperature, pH, salinity and phytotoxic metals/metalloids. Millerocaulis zamunerae thrived in wetlands preserved in the Jurassic geothermal systems of Santa Cruz Province, the same kind of environment in which Equisetum thermale Channing et al. was recorded previously.

Ana Julia Sagasti [] División Paleobotánica, Facultad de Ciencias Naturales y Museo. Becaria Doctoral Consejo Nacional de Investigaciones Científicas y Técnicas, Paseo del Bosque S/N B1900FWA La Plata, Buenos Aires, Argentina. Juan García Massini [] Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), Provincia de La Rioja, UNLaR, SEGEMAR, UNCa, CONICET. Entre Ríos y Mendoza S/N, 5301 Anillaco, La Rioja Argentina. Ignacio H. Escapa [] Museo Paleontológico Egidio Feruglio, Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Fontana 140, U9100GYO, Trelew, Chubut, Argentina. Diego M. Guido [] Instituto de Recursos Minerales (INREMI), Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. Consejo Nacional de Investigaciones Científicas y Técnicas. Calle 64 y 120, La Plata (1900), Argentina. Alan Channing [] School of Earth & Ocean Sciences, Cardiff University, Cardiff CF10 3AT, UK.  相似文献   
94.
Advocates for geographic information system (GIS) education contend that learning about GIS promotes students’ spatial thinking. Empirical studies are still needed to elucidate the potential of GIS as an instructional tool to support spatial thinking in other geography courses. Using a non-equivalent control group research design, this study examines the effect of using Web-based GIS in a world geography course on the development of students’ spatial thinking abilities. The findings indicate that Web-based GIS activities implemented in this study significantly enhanced students’ spatial thinking skills.  相似文献   
95.
96.
李娟 《安徽史学》2018,(4):74-79,96
救亡图存语境下,近代报刊公共空间的建构与其时社会、政治语境有密切关系.《申报·自由谈》是近代中国著名的报纸副刊.1932年留法归国的青年黎烈文主编《自由谈》,期间所进行的改革引人注目,构建起中国近代报刊史上为数不多的公共舆论空间.20世纪30年代,中国面临着对外抗击日军侵略、对内停止内战这一时代主题,《自由谈》的改版恰与时代主题相勾连,使其报刊公共空间的建构成为可能.《自由谈》编辑"兼容并包"的编辑思路集结了当时国内重要的作家,形成多元化的作家群体,而作家群体私人性的杂文写作则成为《自由谈》公共领域的独特话语表述方式.然而,缺乏广泛社会基础的《自由谈》公共空间在国民政府的强力压迫之下难逃"再封建化"的宿命.  相似文献   
97.
98.
This paper presents dental morphological data of Neolithic, Chalcolithic and Bronze Age populations from the Catalan Pre-Pyrenean area. The Neolithic group, in particular, differs from those of surrounding areas in its funerary culture: the building of cists, which is not present in the Sepulcres de Fossa Culture. A minimum number of 118 individuals from this area were studied for this work, and the data were compared with those of other Iberian and European groups. The results indicate that the two micro-regional groups from the Catalan area (Pre-Pyrenean and Pre-Coastal) were biologically different during the Neolithic and the Chalcolithic, but not in the Bronze Age, when they also appeared to be more homogeneous culturally. In addition, both areas differ biologically from coetaneous Italian groups, although those closer to the coast show slightly smaller differences. Finally, the Bronze Age groups also present fewer differences with regard to the Italian Bronze Age’s group. Therefore, the results suggest that the Catalan Neolithic population had two separate origins, related to cultural patterns, and that differences between the groups decreased within time, probably due to trade-related activities. Moreover, the fact that the difference with Italian populations decreased during the Bronze Age suggests major population movements through the Mediterranean that would affect the biological composition of the human groups.  相似文献   
99.
In a previous article, we presented an innovative method to analyze cut marks produced with metal tools on animal bones from a metrical and tridimensional perspective (Maté-González et al. 2015). Such analysis developed a low-cost alternative technique to traditional microscopic methods for the tridimensional reconstruction of marks, using their measurements and sections. This article presents the results of an experimental study to test this photogrammetric and morphometric method for differentiating cut marks generated with metal, flint, and quartzite flakes. The results indicate statistically significant differences among cut marks produced by these three types of raw material. These results encourage the application of this method to archeological assemblages in order to establish a link between carcass processing and lithic reduction sequences on different raw materials and also to define the kind of tools used during butchery.  相似文献   
100.
Chert from the limestones and marly limestones of Castelltallat Formation (Ebro Basin) was widely used throughout prehistoric times in north-eastern Iberia to produce stone tools due to its properties and accessibility. A rough estimate indicates that this rock—either as raw material or as lithic products—was distributed mainly to the north of the outcrops, over an area of 6000–8000 km2. However, other rocks in the area have similar characteristics which can lead to confusion in the interpretation of its prehistoric use and distribution. In order to establish useful archaeometric criteria for differentiating this chert from other similar, the Castelltallat chert is characterised in petrographic, mineralogical and geochemical terms. The chert nodules are found to be homogenous at the macroscopic and microscopic level, with a significant presence of bioclasts, thus indicating they might be formed in a freshwater lake environment by the early diagenetic replacement of carbonates in shallow waters. The mineralogical composition is homogeneously uniform and of a flint type, characterised by an almost exclusive predominance of quartz, without any opaline phases, and a variable proportion of moganite. The iron oxide content is very low, whereas its chemical composition is unusually high in uranium which correlates positively with carbonate content and negatively with silica. Archaeometrical parameters are provided to reach a proper identification of tools knapped with this chert. This way, chert from Castelltallat Formation turns out to be a valuable lithological marker to evaluate the range of mobility of the human groups who lived in the north-eastern Iberia and their contacts with neighbouring areas.  相似文献   
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