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While public health and urban planning were closely linked in the past, today both domains are institutionally separate. In most cases, health intersects with spatial planning processes only through obligatory evaluations, such as environmental impact assessments, or restrictive environmental legislation. This institutionalisation of health criteria in most western countries has difficulty in dealing with recent environmental health challenges, leading to continual distrust and conflict between citizens and the government. This impasse has recently been discussed by academics who acknowledge the complexity of both city and health issues. It seems, however, that the full extent of the issue has not been covered yet, leading to recommendations and frameworks that are useful but fixed and retrospective. This paper moves beyond those fixed frameworks to develop a better understanding of the complexity of the current disconnect and explores ideas for a future planning approach, grounded on new ideas of co-evolutionary and adaptive planning.  相似文献   
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Summary. The plant apparency hypothesis predicts that apparent plants invest in broadly effective defences such as tannins while unapparent plants invest in specific toxins such as alkaloids. The stress hypothesis states that plants invest in cheaper defences if they have evolved in habitats that impose abiotic limitations to plant fitness. We tested these hypotheses by determining the concentrations of alkaloids and tannins in a representative sample of the vascular plants of continental Chile (with exclusion of Pteridophyta, Cactaceae, and Poaceae) consisting of 396 species. In a subsample of 166 species which contained both alkaloids and tannins, we constructed the A/T index (A/T = [alkaloids]/ [tannins]). We discarded the presumed effect of phylogeny (as estimated by taxonomy) on the variation observed in the data because no correlation of A/T with taxonomic relationships among species either at family or genus levels was found in a nested ANOVA with genera nested in families. Concentration of alkaloids was negatively correlated with that of tannins. We compared the value of A/T among species differing in life form (herbs, shrubs or trees), herb longevity (annual or perennial), leaf-shedding manner of woody plants (deciduous or evergreen), latitudinal range, and level of water stress typical in their natural habitat. Unapparent plants (herbs, annual) exhibited higher mean A/T index than apparent plants (shrubs and trees, perennial). A/T did not correlate with latitudinal range. Mean A/T values decreased from deserts to deciduous forests. The comparisons were not always significant due to the inevitable unbalance of the data set which lowers the power of the statistical tests employed. The results suggest that chemical defences are indeed distributed in a non-random manner among plants, and that to a large extent the predictions derived from the apparency and stress hypotheses are sustained.  相似文献   
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This paper proposes to test the ethical acceptability of four styles of agricultural resource management: (1) contemporary industrial integrated systems agriculture, (2) modern industrial input dependent agriculture, (3) continuous traditional agriculture and (4) non-continuous (or swidden) traditional agriculture. The test of ethical acceptability is whether or not these styles of agricultural resource management embrace or are even compatible with that pattern of practical reasoning and interaction among ethical agents which we have independent theoretic grounds for preferring. The preferred sorts of practical reasoning and interaction are those which we find operating in ethical theories which are strongly committed to letting the discretion of ethical agents construct what is right for them to do. Thus the discussion distinguishes several different strengths of constructivist ethics relating them to the work of John Rawls, Immanuel Kant and Onora O'Neill. Then it argues for the theoretic preferability of one particular strength of constructivist ethic. The paper winds up by arguing that only traditional continuous agriculture embodies the preferred sort of practical reasoning and interaction among ethical agents. Further, I argue that this is the only style of agriculture which can embody such reasoning and patterns of interaction. Thus, as we consider the role of agriculture in our plans of international development, we have one reason to try to favor traditional continuous agriculture. To do otherwise would ignore the ethical superiority of the practical reasoning and patterns of interaction of traditional agriculturalists.  相似文献   
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如何通过信息化和工业化深度融合降低能源强度,推动节能减排,是经济发展新常态下亟待解决的重要理论和现实问题.本文以系统间协同演化理论为基础,改进了信息化和工业化融合水平的测度方法,并采用中国大陆除西藏外30个省区2000-2012年的面板数据,探讨信息化和工业化融合对地区能源强度的影响.研究表明,信息化和工业化融合能够显著降低地区能源强度,且其对降低地区能源强度的贡献强于政府干预、技术创新、国际贸易、外商投资和能源价格等因素;信息化和工业化融合对能源强度的影响在东、中、西三个不同经济发展水平的地区之间存在差异,但这种差异并不显著;从动态发展看,信息化和工业化融合对地区能源强度的影响呈增强趋势;产业结构在信息化和工业化融合影响地区能源强度的过程中存在门限效应,只有当第三产业增加值与第二产业增加值之比达到一定水平后(高于0.756 8),信息化和工业化融合对能源强度的影响才变得显著.信息化和工业化融合通过推动技术进步、产业结构升级和资源优化配置三种机制提高能源使用效率,影响地区能源强度.信息化和工业化融合的节能减排效应仍有很大提升空间,应根据不同省区经济发展水平和产业结构差异,采取针对性措施推动信息化和工业化深度融合,充分发挥其在节能减排中的积极作用.在推动通信、交通等基础设施建设的同时,积极发展生产性服务业,为信息化和工业化深度融合节能减排效应的有效发挥创造良好的软环境.  相似文献   
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