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The disappearance of man‐made borders and the need for increased international cooperation seem to prelude a removal of unnecessary obstacles between actors in different countries. This article is concerned with the relationship between political borders, economic development of border regions and networking of companies located there. It presents a ‘state of the art’ of research on border region development and trans‐border networking by companies. Based upon this research, the article concludes with a discussion on conditions that influence the emergence of new corporate networking in border regions, including effective policy action.  相似文献   
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The diversity and ubiquity measures of archaeological macrobotanical remains can be utilized to help define mobility strategies of hunter–gatherers. Differences in the diversity and ubiquity of plant remains are predicted to occur between different types of sites utilized by hunter–gatherers. Such sites include base camps of residentially and logistically mobile groups, as well as special-purpose sites usually associated with logistically mobile groups. The focus upon the importance of strategies of mobility and plant use instead of the typological determination of plant taxa allows for the use of specimen types in such analyses when scientific identifications are difficult to make. Data from the archaeological site of San Jacinto 1, located in northern Colombia, are utilized to examine this relationship.  相似文献   
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This paper extends a compartmental epidemiological model for HIV transmission and AIDS incidence to include hierarchical and expansion spatial diffusion. An implication of the resultant model is that hierarchical diffusion causes the large infection growth rates of densely populated areas at the top of the central places hierarchy to “chain” down and dominate small local growth rates during the exponential-growth phase of the epidemic. Also, hierarchical diffusion causes a high transient growth rate in the first few years of a local epidemic. The spatial compartmental model fits observed AIDS incidence spatial diffusion patterns in Ohio reasonably well.  相似文献   
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This paper, originally presented to the AESOP‐ACSP joint conference in Oxford in 1991, stresses that both in Europe and in the US, there is a major difference for planning in the switch from boom to recession. During the 1990s a major challenge will be to find new ways of public‐private partnership in financing new urban infrastructure at a time when developer contributions — a major innovation of the 1980s — have dried up. This particularly applies to the European high‐speed train system — one critical element of which will run through the East Thames Corridor, one of Britain's major urban developments in the coming years. In the US, planners are likely to remain more locally focused, less internationally concerned, than in a Europe in which national barriers are rapidly eroding.  相似文献   
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