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Chen Xiu-Qin Arthur J. Boucot 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):403-412
Leptocoeliid brachiopods from the Early Devonian Baruntehua Formation of Dong Ujimqin Qi, northeastern Inner Mongolia were assigned to Leptocoelia by Su (1976) and Zhang(1983), and subsequently to Pacificocoelia by Hou & Boucot (1990). Transverse serial sections of Pacificocoelia sinica are illustrated hère, for the first time, based on topotype specimens. The known geographic range o Pacificocoelia is from northern China, North America, South America and Kazakhstan (Eastern Americas Realm and also occurs in east-central Asia). Atlanticocoelia is regarded hère as a junior synonym of Pacificocoelia. 相似文献
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Arturo César Taboada Arthur J. Mory Guang-Rong Shi David W. Haig María Karina Pinilla 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):207-223
Taboada, A.C., Mory, A.J., Shi, G.R., Haig, D.W. & Pinilla, M.K., 12.11.2014. An Early Permian brachiopod–gastropod fauna from the Calytrix Formation, Barbwire Terrace, Canning Basin, Western Australia. Alcheringa 39, xxx–xxx. ISSN 0311-5518A small brachiopod–gastropod fauna from a core close to the base of the Calytrix Formation within the Grant Group includes the brachiopods Altiplecus decipiens (Hosking), Myodelthyrium dickinsi (Thomas), Brachythyrinella narsarhensis (Reed), Neochonetes (Sommeriella) obrieni Archbold, Tivertonia barbwirensis sp. nov. and the gastropod Peruvispira canningensis sp. nov. The fauna has affinities with that of the late Sakmarian?early Artinskian Nura Nura Member directly overlying the Grant Group in other parts of the basin but, as with all lower Cisuralian (and Pennsylvanian) glacial strata in Western Australia, its precise age remains poorly constrained, especially in terms of correlation to international stages. Although the Calytrix fauna lies within the Pseudoreticulatispora confluens Palynozone, the only real constraint on its age (and that of the associated glacially influenced strata) is from Sakmarian (Sterlitamakian) and stratigraphically younger faunas. A brief review of radiometric ages from correlative strata elsewhere in Gondwana shows that those ages need to be updated. The presence of Asselian strata and the position of the Carboniferous?Permian boundary remain unclear in Western Australia.Arturo César Taboada [ataboada@unpata. edu. ar], CONICET-Laboratorio de Investigaciones en Evolución y Biodiversidad (LIEB), Facultad de Ciencias Naturales, Sede Esquel, Universidad Nacional de la Patagonia ‘San Juan Bosco’, Edificio de Aulas, Ruta Nacional 259, km. 16,5, Esquel U9200, Chubut, Argentina; Arthur Mory [arthur. mory@dmp. wa. gov. au], Geological Survey of Western Australia, 100 Plain Street, East Perth, WA 6004, School of Earth and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; Guang R. Shi [grshi@deakin. edu. au], School of Life and Environmental Sciences, Deakin University, Melbourne Burwood Campus, 221 Burwood Highway, Burwood, Victoria 3125, Australia; David W. Haig [david. haig@uwa. edu. au], School of Earth and Environment (M004), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; María Karina Pinilla [mkpinilla@fcnym. unlp. edu. ar], División Paleozoología Invertebrados, Museo de Ciencias Naturales de La Plata, Paseo del Bosque s/n, 1900 La Plata, Buenos Aires, Argentina. 相似文献
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ABSTRACTIn this paper, we explore the evolving norms and dispositions of creativity and enterprise of engineering students using data gathered from a newly established technology and engineering-focused university called ‘UniTech’ located in Singapore. Based on interviews with students, we seek to explain (1) what they learn, reject, adopt and appropriate; (2) the kinds of challenges they face and (3) the unexpected and serendipitous outcomes of their learning. Through an integrated engineering curriculum focusing on design, students learn to be technically competent, creative and entrepreneurial persons. This paper considers how the curriculum works as a set of formal procedures preparing students for a future ‘knowledge-based economy’ imagined to be technology-intensive, dynamic and filled with opportunities but also increasingly uncertain. We analyse how students at UniTech negotiate this design-focused curriculum where experiences of creativity, open-ended possibilities and holistic perspectives intersect with the national economic agenda of a knowledge-based economy. 相似文献
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Abstract. The replacement of the Soviet Union by independent states rather than by a loose confederation of component republics reflects (in part) the demands for change that were being expressed by mass publics. What caused the people to reject decentralisation of authority within the existing state structure and chose rather to support movements that insisted on the establishment of independent states? We examine whether concerns about ‘discriminatory redistribution’ and ‘cultural preservation’ were more important than questions of ‘efficiency’ or ‘relative deprivation’ as motivations behind support for secession. The analysis is based upon public opinion data from Russia, Ukraine and Lithuania gathered in May of 1990 and in June of 1991. We conclude that although issues related to cultural preservation and discriminatory redistribution were foremost in the minds of separatists, concerns about efficiency and improved management in government are also relevant for understanding support for separatism. 相似文献
46.
The statistics Gi(d) and Gi*(d), introduced in Getis and Ord (1992) for the study of local pattern in spatial data, are extended and their properties further explored. In particular, nonbinary weights are allowed and the statistics are related to Moran's autocorrelation statistic, I. The correlations between nearby values of the statistics are derived and verified by simulation. A Bonferroni criterion is used to approximate significance levels when testing extreme values from the set of statistics. An example of the use of the statistics is given using spatial-temporal data on the AIDS epidemic centering on San Francisco. Results indicate that in recent years the disease is intensifying in the counties surrounding the city. 相似文献
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