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Helen Walker and Paul Murdin report on the Royal Astronomical Society's involvement in government action to protect dark skies. 相似文献
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Dealing with drought: The challenge of using water system technologies to break dryland poverty traps 总被引:2,自引:0,他引:2
We explore strategies among farmers in semi-arid Tanzania to cope with drought, and investigate if access to a local supplemental irrigation system (the Ndiva system) can improve coping capacity. Results show high dependency on local ecosystem services when harvests fail, and indicate that farmers commonly exhaust asset holdings during droughts. Ndiva access did not have any direct effects on coping capacity, but seemed to have some indirect effects. Drawing on our findings we discuss the complexity of escaping persistent dryland poverty, and outline the circumstances under which small-scale water system technologies, such as Ndiva irrigation, may help. 相似文献
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Changes in solid solution limits, which must occur as crystallization proceeds, are used to interpret crystallization trends of pyroxenes from the Bushveld Intrusion, from oxidised and reduced basaltic lavas, and from lunar lavas. 相似文献
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Abstract: This paper discusses three walking tour guides prepared for the 12th International Conference of Historical Geographers. It argues that the guides are innovative in terms of format, content and ironic sensibility. It construes them as devices for re-imagining Auckland's urban heritage. 相似文献
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Investment returns are produced by combining financial assets with human capital, the decision-making protocols of investment houses, and the electronic infrastructure that supports the flow of information about investment. At the center of the production process stand senior managers; their power and authority in the production process is fundamental to the performance of investment organizations. This article provides a model of the production of investment returns in financial centers and spatially extensive financial markets. We begin with Coase's theory of the firm but go beyond models of the firm that represent commodity-producing industries. Having substantiated the model of investment management, it is applied to institutions that seek investment returns in geographically extensive financial markets. Operating in financial markets at a distance from home jurisdictions is an increasingly important aspect of investment management. Given recent turmoil in global financial markets, financial houses have sought higher rates of return from markets in which they have little direct experience. At issue is how different types of financial organizations (large and small, growing and declining) produce investment returns in this new environment. 相似文献