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21.
During late winter and spring, hunter-gatherers in temperate, subarctic, and arctic environments often relied on diets that provided marginal or inadequate caloric intakes. During such periods, particularly when stored food supplies dwindled or were used up entirely, lean meat became the principal source of energy. Nutritional problems associated with high-protein, low-energy diets are discussed. These problems include elevated metabolic rates, with correspondingly higher caloric requirements, and deficiencies in essential fatty acids. The relative benefits of adding fat or carbohydrate to a diet of lean meat are evaluated in light of the protein-sparing capacities of these two nutrients. Experimental data indicate that although both enhance high-protein, low-energy diets, carbohydrate is a more effective supplement than fat. Given the nutritional inadequacies of a lean-meat diet, the paper concludes with a discussion of alternative subsistence strategies that increase the availability of carbohydrate or fat at the critical time of year.  相似文献   
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Based on two years of participatory video drama (PVD) research with men and women in the city of Hu?, this article explores perspectives on, and experiences of, socio-economic transition and its influence on domestic life in Vietnam. Through a combination of output analysis, group screening sessions and individual interviews, it concentrates on the themes of marriage, parenting and ‘social evils’ which emerged in the PVD. It demonstrates how familial tensions collectively identified in the workshop and told in a single video-narrative are complicated by the more nuanced discourses that emerge from co-produced analysis in the post-production period. These illuminate a greater plurality of voices towards the liberalisation of the Vietnamese economy and the new life choices that this brings.  相似文献   
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Rozefelds, A.C., Dettmann, M.E., Clifford, H.T. & Lewis, D., August 2015. Macrofossil evidence of early sporophyte stages of a new genus of water fern Tecaropteris (Ceratopteridoideae: Pteridaceae) from the Paleogene Redbank Plains Formation, southeast Queensland, Australia. Alcheringa 39,. ISSN 0311-5518.

Water fern foliage is described from the Paleogene Redbank Plains Formation at Dinmore in southeast Queensland. The material, which is based upon leaf impressions, records early sporophyte growth stages. The specimens occur at discrete levels in clay pits at Dinmore, and the different leaf stages present suggest that they represent colonies of young submerged plants, mats of floating leaves, or a mixed assemblage of both. The leaf material closely matches the range of variation evident in young sporophytes of Ceratopteris Brongn., but in the complete absence of Cenozoic fossils of the spore genus Magnastriatites Germeraad, Hopping & Muller emend. Dettmann & Clifford from mainland Australia, which are the fossil spores of this genus, it is referred to a new genus, Tecaropteris. The record of ceratopterid-like ferns adds significantly to our limited knowledge of Cenozoic freshwater plants from Australia. The geoheritage significance of sites, such as Dinmore, is discussed briefly.

Andrew C. Rozefelds [], Queensland Museum GPO Box 3300, South Brisbane, 4101, Queensland, Australia and School of Earth Sciences, University of Queensland, St Lucia, 4072, Queensland, Australia; Mary Dettmann [], H. Trevor Clifford [] and Debra Lewis [], Queensland Museum, GPO Box 3300, South Brisbane, 4101, Queensland, Australia.  相似文献   

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Drawing on three select case studies and feminist engagements with mobility studies, I illustrate the Irish state’s use of a dialectic of gendered and racialized citizenship, and mobility and fixity, in the creation of ‘new geographies of belonging and exclusion’. Using detailed analyses from select cases, I argue for more nuanced feminist engagements with mobility that acknowledge and analyse ‘processes and trajectories’ in relation to a geopolitics of abortion – one that eschews undifferentiated uses of the category migrant and discourses of tourism, in analysing abortion in the Republic of Ireland. I expose how their use constructs limited ideas about gender, nation and Irishness to assure exclusions from Ireland, and from its diaspora.  相似文献   
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Excavations at the site of Langley’s Lane, Bath and North-East Somerset, have revealed an important sequence of Late Mesolithic activity focused around an active tufa spring. The sequence of activity starts off as an aurochs kill and primary butchery site. Culturally appropriate depositional practices occur through the placement of a selection of bone in the wetland of the spring and the digging of pits around the spring margins. The spring at Langley’s Lane continued to be visited and more animal bone and lithic material was placed in the wetland. Finally, visits to the site involved yet more formalized activity in the form of pit digging and the creation of a stone surface. Activities such as these are difficult to locate in the archaeological record and Mesolithic ritual activity rare, making this a site of some significance to studies of Mesolithic NW Europe.  相似文献   
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