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排序方式: 共有697条查询结果,搜索用时 46 毫秒
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Jane Battersby 《Geografiska annaler. Series B, Human geography》2012,94(2):141-159
Urban food security is a significant development challenge in sub‐Saharan Africa. However, the field is currently under ‐researched and under‐theorized. Urban food insecurity, where it is considered, has been viewed through a development studies lens that views food insecurity as a household‐scale problem. There has been significant focus on food deserts in developed countries as one way of engaging with such insecurity. The food deserts research views food insecurity through a social exclusion and food justice lens. This article introduces the food desert concept to provide a conceptual tool to begin to understand the spatial determinants of urban food insecurity, which are not well captured by the existing framings of food security in the region. Using data from a 2008 household food security survey conducted in Cape Town, the paper highlights gaps in the food deserts approach, most significantly its neglect of non‐market sources of food and of household decision‐making processes. The paper therefore concludes by suggesting a new approach which takes the household's assets, abilities and decision‐making as the starting point and overlays this with the market and non‐market foodscapes accessed by these households. 相似文献
694.
Jane K. Beitscher 《Journal of Medieval History》1976,2(3):181-191
The family, be it nuclear or extended, is integral to all historical societies. Usually, the primary bond is between older and younger males, most often between father and son. As an economic, political and social unit the family is supposed to provide solidity, stability and protection for all its members.As part of the kinship unit children from primary and secondary bonds with nuclear and extended relatives. Adverse demographic and economic forces, however, can break these alliances, disrupting and exacerbating the intimacies of daily life. Families in crisis turn upon weaker members, often expelling young and old from the hearth. As a limited numerical unit the family provides only a small arena for vented hostility. After wreaking inner devastation, the survivors loose a concentrated storm of repressed hatred upon a much larger, but equally vulnerable institution: the local Church. Overwhelming and seemingly irrational economic and social forces pit young against old; eventually, new, external bonds of allegiance are erected over the shards of the broken family.1 相似文献
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Brandi Lee MacDonald R.G.V. Hancock Aubrey Cannon Alice Pidruczny 《Journal of archaeological science》2011,38(12):3620-3630
The use of ochre and its presence in archaeological contexts is well documented archaeologically, ethnographically and historically. Elemental analysis of ochre is becoming increasingly common as a method for identifying ancient quarrying and mining practices, and for identifying patterns of resource use, trade and exchange. As this type of work has become more common it has become apparent that two critical issues need to be considered: (1) the need for systematic identification of trends and patterns in ochre geochemistry using appropriate statistical analyses, and, (2) consideration of geographic and geologic scale in relation to ochre chemistry. Because ochre is a heterogeneous material relative to other raw material types, it is necessary to apply multivariate and discriminant statistics to differentiate geochemical groups within a sample set. However, caution must be taken when interpreting statistical results at face value. Local geologic and geomorphologic conditions play a significant role in ochre chemistry and need to be taken into account when interpreting analytical results. The purpose of this project was to determine if geochemically distinct groups of ochre could be distinguished through neutron activation analysis (NAA) of archaeological and geological ochres from the central coast of British Columbia, Canada. The results show that it is possible to satisfy the provenance postulate and to differentiate chemical groups through elemental characterization and using multivariate statistical methods. 相似文献
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