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排序方式: 共有136条查询结果,搜索用时 15 毫秒
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This paper presents the first multidisciplinary synthesis of the Middle Stone Age sequence of Diepkloof Rock Shelter (South Africa). We explore the main cultural changes that characterized southern African hunter–gatherer societies from OIS 5 to the beginning of OIS 3. We discuss the tempo of these changes, test the current interpretative hypotheses and explore an empirical model to explain the early appearance of symbolic marking within the Pleistocene hunter–gather societies of southern Africa.  相似文献   
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The occurrence of a damaging earthquake provides an opportunity to compare observed and estimated damage, provided that detailed observations of the earthquake effects are made in the field. A question that arises is whether such comparisons can provide the basis for validation of an earthquake loss model. In order to explore this issue, a case study loss model for the northern Marmara region has been set up and the losses have been calculated for various ground-motion fields that arise when different assumptions are made about the ground-motion variability. In particular, the influence of removing the inter-event variability for a scenario earthquake and modeling spatial correlation among ground motions is studied. Further analyses are conducted assuming that a number of accelerograms are available within the region and that knowledge of spatial correlations among ground motions can therefore be used to better predict the motions at sites in the vicinity of the recording stations. The results demonstrate that unless one has a dense network of accelerographs (commensurate with the geographical resolution of exposure), then the variability in the losses cannot be sufficiently reduced to allow validation of the loss model.  相似文献   
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Nguyen, J.M.T., Boles, W.E., Worthy, T.H., Hand, S.J. & Archer, M., 2014. New specimens of the logrunner Orthonyx kaldowinyeri (Passeriformes: Orthonychidae) from the Oligo-Miocene of Australia. Alcheringa 38, 000–000. ISSN 0311–5518.

Logrunners (Orthonychidae) are a family of ground-dwelling passerines that are endemic to the Australo-Papuan region. These peculiar birds are part of an ancient Australo-Papuan radiation that diverged basally in the oscine tree. Here we describe eight fossil tarsometatarsi of the logrunner Orthonyx kaldowinyeri, and a distal tibiotarsus tentatively assigned to this species from sites in the Riversleigh World Heritage Area, Australia. The new fossil material ranges in age from late Oligocene to early late Miocene, and extends the temporal range of the Orthonychidae into the late Oligocene; this is the geologically oldest record of the family. These specimens also include the oldest Cenozoic passerine fossils from Australia that can be confidently referred to an extant family. The distinctive features of the tarsometatarsus and tibiotarsus of extant logrunners, which are probably related to their unusual method of foraging, are also present in O. kaldowinyeri. Assuming that O. kaldowinyeri had vegetation requirements similar to those of extant logrunners, its presence in various Riversleigh sites provides clues about the palaeoenvironment of these sites.

Jacqueline M.T. Nguyen [] (author for correspondence), Suzanne J. Hand [], Michael Archer [], School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia; Walter E. Boles [], Ornithology Section, Australian Museum, 6 College Street, Sydney, NSW 2010, Australia; Trevor H. Worthy [], School of Biological Sciences, Flinders University, Adelaide, SA 5001, Australia. Received 19.9.2013; revised 11.10.2013; accepted 25.10.2013

http://zoobank.org/urn:lsid:zoobank.org:pub:F4F6219A-22A3-4F6B-8AEE-2957A227C0E0  相似文献   
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This article presents a thematic network analysis of Dabiq—a prominent English-language e-magazine produced by the Islamic State. Through formal qualitative analysis, the article examines the e-magazine’s first 13 issues in order to better understand its structure, evolution and intended audiences. In terms of structure, thematic network analysis provides a comprehensive and holistic understanding of Dabiq’s themes, identifying a range of concerns that are broader and more complex than is often supposed by academic and professional commentators. In terms of evolution, this analysis reveals a thematic landscape that has demonstrated considerable dynamism over four distinct phases throughout the magazine’s publication. In terms of understanding audiences, it is argued that Dabiq has been particularly engaged with the manipulation of group-level identities in an apparent attempt to garner support from global audiences. Themes related to allegiance, the group’s strengths and victories, and territorial expansion all feature consistently and prominently. They seek to create an in-group identity centred on victory, and to frame the Islamic State’s expansion and successes as a group achievement on behalf of Islam itself. Additionally, Dabiq provides the Islamic State with an opportunity to justify its actions and its religious authenticity to a broader Muslim audience, and thus provide the Islamic State with legitimacy beyond its borders. Recognising these thematic dynamics will be important for those engaged in counter-messaging and the development of counternarratives.  相似文献   
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Hawārī are traditionally logboats carved from a single tree into a double-ended vessel which can be propelled by either sails or paddle. Hawārī can be found throughout the Indian Ocean from India through to East Africa, yet little is known about this ubiquitous vessel. The aims of this research are to address this lacuna in our knowledge by documenting the rich source of hawārī present on the island of Socotra, Yemen.
© 2009 The Author  相似文献   
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Abstract:  In contrast to the US environmental justice movement, which has been successful in building a networked environmentalism that recognises—and has impacted upon—national patterns of distributional (in)equalities, campaigns in the UK have rarely developed beyond the local or articulated a coherent programme of action that links to wider socio-spatial justice issues or effects real changes in the regulatory or political environment. Our purpose in this paper is to extend research which explores the spatial politics of mobilisation, by attending to the multi-scalar dynamics embedded in the enactment of environmental justice (EJ) in north-east England. It is an approach that is indebted to recent work on the scalar politics of EJ, and also to the network ideas associated with actor-network theory (ANT)-inspired research on human–nature relations. Our account provides preliminary reflections on the potential for an "assemblage" perspective which draws together people, texts, machines, animals, devices and discourses in relations that collectively constitute—and scale—EJ. To conclude, and building upon this approach, we suggest future research avenues that we believe present a promising agenda for critical engagement with the production, scaling and politics of environmental (in)justice.  相似文献   
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