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The Scottish Executive has adopted a policy to combat Scotland's declining population by encouraging inward migration. Using a multi‐state population model this paper presents nine long‐term population scenarios for Scotland using three net international migration levels and three fertility paths. The results show inward migration can slow population decline but makes little difference to population ageing. Without a higher fertility rate Scotland's population will become demographically unsustainable. Our simulations show that a higher fertility rate substantially reduces the future ageing.  相似文献   
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During the late‐Midlandian (25–13 14C ka BP), the last Irish Ice Sheet was thicker in the Western Mourne Mountains than previously argued. Geomorphological and sedimento‐logical analysis shows that regional ice from the Irish Ice Sheet spilled over the mountains, reaching a major limit 5 km along Pigeon Rock Valley. These findings differ from the previous view that a local valley glacier occupied the valley during this period. The pattern of deglaciation was reconstructed using glacial and periglacial evidence. A complex topographic environment in the upper reaches of the valley suggests that regional ice stagnated as it wasted away. During the Nahanagan Stadial (Younger Dryas, ca. 11–10 ka 14C BP) an arcuate ridge was formed on the western flank of the valley. Calculations suggest that the Equilibrium Line Altitude, influenced by topographic conditions favourable for snow accumulation, was approximately between 1736 m and 1386 m lower during the Nahanagan Stadial than at present.  相似文献   
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Since 2005, a burgeoning wave of Chinese investments has set off a new ‘minerals boom’ in the Australian iron ore and coal mining sectors. While normally a welcome development, the state-owned and strategic nature of the investors has raised concerns in Australia about how these should be regulated. As a result, in February 2008 the Australian government declared an intention to more closely screen foreign direct investment (FDI) from state-owned sources, which both supporters and detractors alike have claimed is evidence of ‘resource nationalism’ in Australia's approach towards its trade and investment relationships with China. This article challenges this understanding through an examination of the characteristics of Chinese mining FDI, the dilemmas these present to the Australian government, and the relatively restrained nature of its response. Through this, Australia's FDI policy is explained as a defensive move against the potential for strategic behaviour by Chinese investors resulting from their state ownership, rather than any national program to subject minerals trade and investment to political control. On this basis, the article argues that Australian government policy instead evidences a ‘resource liberalism’ approach, which intends to ensure that the governance of Australia's minerals trade and investment with China remain market-based processes.  相似文献   
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A key area in the analysis of urban structural evolution is identifying discontinuities. Effective analysis could improve long‐term forecasting and provide a better understanding of how to steer an urban system toward a desirable future state. We use a simple aggregate retail model to demonstrate an algorithm for identifying discontinuities in model parameter space. Explorations of retailing in both Greater London and South Yorkshire in the United Kingdom illustrate how understanding a system's potential for discontinuity can provide insights for both policy makers and retail businesses. The Harris and Wilson model, described in the section so‐named, is used as a simple archetype to illustrate the new framework. This model can be developed in a straightforward way to incorporate further refinement. In “ Executing the model and visualizing the results ,” we describe a single model run and in “ Investigating discontinuities ,” we explain our framework for detecting and analyzing discontinuities. “ Identifying discontinuities in the London retail system ” shows the results of applying this methodology to the Greater London retail system, and in “ Practical applications ,” we explore the policy applications for this technique as related to the decline of town centers in the South Yorkshire retail system. Some concluding comments are offered in “ Conclusions .”  相似文献   
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