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991.
When heat treatment of silcrete for stone knapping was first discovered in the South African Middle Stone Age (MSA), the procedure used for it was suggested to be similar to the one used for heat treatment of finer rocks in other parts of the world: slow sand-bath heating. This comparison may have been based on published data from the fields of ethnography, experimentation and archaeology, describing sand-bath like structures and processes. In this review, I discuss whether the available data from these three fields indeed justify the suggestions that sand-bath heating was used in the context of MSA silcrete heat treatment. A careful revaluation of the available data shows that, although sand-bath heating is a widely accepted procedure that is documented in other parts of the world, understanding the earliest known cases of heat treatment in the MSA calls for another technical procedure.  相似文献   
992.
Radiocarbon dates for camelthorn trees in the Namib Desert reflect marked variation in rainfall during the last 1,000 years. These records and other proxy climate data indicate a loose teleconnection with the southern African climatic record, especially for regionwide episodes of dry conditions resulting from extreme El Niño events. However, archaeological evidence of hunter-gatherer and nomadic pastoralist occupation does not mirror the climate record by indicating that the desert was only inhabited during periods of favourable rainfall. It points instead to a specialized strategy which allowed continuous occupation of the Namib Desert despite extreme fluctuations in rainfall, by combining the use of primary resource areas with opportunistic use of secondary, ephemeral resources in an alternating density-dependent and density-independent dynamic.  相似文献   
993.
This article discusses how archaeological sites in Sierra Leone, and by extension much of West Africa, can be identified through vegetation patterns (vegetation signatures) detectable in very high-resolution (VHR) multispectral satellite imagery. Settlement sites typically have a differing pattern of vegetation from the surrounding landscape, including concentrations of very large trees with sociocultural and historical significance: cotton (Ceiba pentandra) and baobab (Adansonia digitata). These features are conspicuous elements of the landscape both from the ground and in aerial imagery. Two complementary methods of using VHR multispectral satellite imagery are discussed in this paper: visual interpretation and semi-automated subpixel classification. These techniques are aiding ongoing archaeological survey of the Sierra Leone River Estuary. The impact of recently renewed industrial activity at a site of probable archaeological significance is also assessed through visually interpreted VHR satellite imagery.  相似文献   
994.
At a regional scale, a variety of actors from all three sectors of private, public and civil society act together in a philanthropic field. This article deals with the question of how cooperation in charitable action unfolds in this field. Using the example of the region of Heilbronn-Franconia, the empirical case unpacks the dominance of local and regional forms of philanthropy and reconstructs two successful examples of intersectoral collaboration. However, the analysis also demonstrates the limits of the external designability that are due to the individuality of charitable actors, their diverse objectives and the contextuality of the regional environment. The realization of synergies through regional governance therefore succeeds only by respecting the dedication and self-determination of philanthropic commitment and by creating legitimate and sensitive structures of moderation and facilitation.  相似文献   
995.
Factory closures, relocations and extensive measures to reduce personnel have consequences far beyond the affected employees – the social and economic coherence of the location and region are often negatively affected, too. This presents an interesting and important field for economic and applied geography. Apart from the development and evaluation of concepts of instruments of regional development, geographers can discuss and conceive options and obstacles for compensation and replacement measures after corporate restructuring. This text discusses structural and individual opportunities and obstacles in implementing company-induced economic development measures in the wider context of the corporate responsibility debate.  相似文献   
996.
997.
Firms assume increasing importance within co-operative modes of regional and urban governance. Further to just filling gaps left by the retreat of the welfare state, firms recognise the impact of their regional and local business environment on their performance, especially when it comes to attracting and retaining highly-skilled personnel. As an introduction to this issue, this contribution introduces the basic concept of corporate social responsibility and its regional variation, corporate regional responsibility.  相似文献   
998.
999.
Due to climate change, but also because of the demographic change and financial constraints in many municipalities, the future of cities is a currently much-discussed topic. Conflicts over land-use are inevitable: As densification is an essential principle in growing cities, the pressure on open (green) spaces rises. Climate Change and water-management as well as mobility-issues and air-quality confront municipalities with new challenges, in terms of open space planning and greenery in the city. It is necessary to save the existing green in these days of budget-shortage and other priorities in communities. Municipalities have to raise new strategies to strengthen the awareness of the value of green in public and in the local business.  相似文献   
1000.
Events do have, in addition to economic effects, impact on the quality of life of the affected population. Using a case study from the city of Bamberg this article addresses the subjective contentment with larger events. The results show variation in the range of contentment depending on age and time of residency in the city. Furthermore, it becomes obvious that the particular expectation on “life in the inner city” shapes the contentment. Cities should pay attention to this social heterogeneity when deploying strategies of revitalisation through festivals and events. They should take it seriously by using tools of collaborative planning to preserve the multi-functionality of inner cities.  相似文献   
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