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David R. Braun Joanne C. Tactikos Joseph V. Ferraro Shira L. Arnow John W.K. Harris 《Journal of archaeological science》2008
Transport of resources is a major feature of Oldowan hominin technological adaptations. Comparisons between different Oldowan localities often employ measures of transport that are based on artefact attributes as proxies for the intensity of raw material utilization. The Technological Flake Category system [Toth, N., 1985. Oldowan reassessed: a close look at early stone artifacts, Journal of Archaeological Science 12, pp. 101–120] has been used extensively to infer the relative intensity of lithic reduction within Oldowan assemblages. Here we use a large experimental sample to test the relationship between a flake's stage in a reduction sequence and various quantitative attributes. We demonstrate how many previously described attributes are affected by initial core size. We then develop a multiple linear regression model that incorporates several variables to predict the placement of a flake within a generalized reduction sequence. The model is then applied to Oldowan assemblages in the Koobi Fora Formation which explores the strengths and weaknesses of different methods of investigating reduction intensity on an assemblage level. 相似文献
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Ill children with chronic diseases, such as tuberculosis, have faced difficult lives. Poverty proved a factor in their susceptibility to disease, their abandonment, and their treatment. When public health policies in Buenos Aires shifted from ignoring children to viewing them as victims who needed protection, government agencies, charitable organizations, public schools, and hospitals developed special programs that emphasized both prevention and cure of childhood tuberculosis. Argentine physicians and hygienists supported programs that were similar to those in Europe and the United States. Despite efforts, from 1880 to 1920, diagnosis of tuberculosis remained problematic, health professionals failed to prevent tuberculosis in children, and physicians were unable to cure the disease. 相似文献
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Canada is a large nation, approximately 1 billion hectares in size, and until recently, no national assessment of forest fragmentation had been undertaken. To assess national level biodiversity and ecosystem condition, national drivers of forest fragmentation are identified as being either primarily natural (e.g., resulting from wildfires, water features, or topography), or primarily anthropogenic (e.g., resulting from urbanization or roads and associated activities such as forest harvesting and oil and gas exploration). The relative importance of each of these fragmentation drivers within Canada's ten forested ecozones, which occupy approximately 650 million ha, is assessed using ecozone summaries and standard scores. Forest pattern metrics were generated from a Landsat‐derived land cover product and fragmentation drivers were characterized using available national datasets. Through this analysis, we combine and portray the relative importance of forest patches with spatial layers indicative of natural and anthropogenically induced conditions as driving various fragmentation regimes over the forested area of Canada. The forest fragmentation in Canada can be characterized primarily by natural drivers, whereas fragmentation regimes attributable to anthropogenic drivers are typically regionally located and related to industrial activities and access (i.e., roads). We identify three scenarios in our results that characterize forest fragmentation in Canada: ecozones with similar forest patterns but different drivers; ecozones with similar patterns and drivers; and finally, ecozones with both different patterns and different drivers. Our findings indicate that national assessments of forest fragmentation should account for both natural (and inherent) and anthropogenic sources of fragmentation. 相似文献
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Joanne Ella Parsons 《Irish Studies Review》2014,22(4):535-536
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Vera Chouinard 《对极》2014,46(2):340-358
Most of what is known about disabled women's and men's lives is based on research conducted in the global North despite the fact that 80% of the world's one billion disabled people live in countries of the global South. This article addresses this gap in our understanding of disabled people's lives by examining impairment and disability as outcomes of processes of social embodiment that unfold in an unequal global capitalist order. Drawing on 87 interviews conducted with disabled women and men in Guyana, the article illustrates how colonial and neo‐colonial relations of power and processes of development give rise to material conditions of life such as extreme poverty and male violence that contribute to impairment and disability. The article concludes by discussing the article's contributions, challenges in developing southern perspectives on impairment and disability, and the need to address socio‐spatial injustices experienced by disabled people in the global South. 相似文献
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This article summarizes the protocol applied to analyse the spatial consequences of diverse regional plans included in the General Spatial Planning of Catalonia (GSPC) municipalities since 1985. The main aims of the GSPC were to achieve a more balanced distribution of population, avoiding Barcelona metropolitan region congestion, coastal overcrowding and mountain areas depopulation, and to improve mobility infrastructures and social welfare. The methodology used was based on factor analysis that reduced 30 socioeconomic and geographic variables provided by different sources into a smaller number of common factors. Afterwards a non-hierarchical clustering was employed to simplify the analysis of dynamics. The six first common factors retained in the model explained the 82.6% of total variance. After labelling them, six clusters were mapped to describe the most important dynamics: urban sprawl, urbanalization, depopulation, reterritorialization and coastalization. Finally, some socio-environmental consequences of such dynamics are discussed. 相似文献
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