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231.
当前的生态危机主要是由于人与自然的关系失衡造成的。生态环境恶化造成的可怕后果已经影响了经济和社会的发展。从马克思主义哲学角度对生态危机来源进行深入分析,有助于反思人类在地球上的角色定位,以及应负的责任,重构人与自然关系。  相似文献   
232.
应用人体外周血淋巴细胞微核试验测定了29种取代苯酚类化合物的遗传毒性(72h-lgMN20),并对此类化合物的遗传毒性大小进行了分析比较,同时构建了遗传毒性与分子结构参数之间的QSAR 模型.结果表明,29种取代苯酚类化合物都显著地导致了微核的产生,具有明显的遗传毒性;遗传毒性大小与取代官能团及官能团位置存在一定的规律;遗传毒性的大小与分子结构参数溶剂连接性指数(X2SOL)、自由基信息参数(ICR)、零阶平均分子连接性指数(X0A)及修正指数(LOP)之间存在良好的结构-活性相关关系,所建模型的相关系数r2= 0.816,可以用于定量评估其它取代苯酚类化合物的遗传毒性.  相似文献   
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In this article, we review the virology, pathology, epidemiology and clinical spectrum of intrauterine human parvovirus B19 (B19V) infection, including intrauterine fetal death, non-immune hydrops fetalis, thrombocytopenia and neurological manifestations such as pediatric stroke and perivascular calcifications. In addition, we discuss the new insights into the neurodevelopmental outcome of intrauterine B19V infection. Current diagnosis and management of B19V infection is summarized, including a diagnostic and follow-up flowchart for practical clinical use. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
236.
It is difficult to make general recommendations that apply to all ecosystems. There is still a relative dearth of studies that allow the manager or visitor to come up with specific practices that are the best for their area. The preferred method of disposal remains to dig a small hole (cat hole) and bury the waste. Other site specific methods are also discussed. Treatment of drinking water has become standard practice for most backcountry travel. With such treatment, there is little evidence currently to suggest that the health hazard to humans is great enough to impose further regulation in areas currently using cat holes.  相似文献   
237.
1INTRODUCTION Human Capital Theory(HCT)'s idea origin recalls westernclassical political economics in the eighteen century.HCTcame into being in the middle and later periods of the20century,sprang up in the1960s and1970s,was introducedinto China in the1980s and is still one of the hotspotsin economic research.Foreign and domestic scholars havemade a lot of deep researches and important achievements.2FOREIGN RESEARCHIn the1950s,facing many"economic enigma"such as"Solow residual"an…  相似文献   
238.
基于贝叶斯网络的人因可靠性评价   总被引:2,自引:7,他引:2  
提出一种贝叶斯网络的人因可靠性评价(HRABN)方法,其中的每个因子对应于贝叶斯网络中的节点,该方法可对人因可靠性作定量分析和定性分析。在定性分析上,节点的因果关系(HRA中的因子关系)及需要改进的薄弱节点都直观地显示在层次图中;在定量分析方面,对节点因子后验概率的推断通过HRA中的先验信息(包含仿真数据、现场操作及专家知识等)和最新信息得到。如果人因可靠性贝叶斯网络中的每个节点的先验概率分布和后验概率分布都已知,模型的可信性就可通过贝叶斯因子进行定量验证。贝叶斯网络扩展性好,当有新的节点因子需要考虑时,只需要补充对应的节点;笔者的方法也能很好地应用在不同行业的HRA。  相似文献   
239.
This study analyzes the fishing areas or spots used by artisanal fishers of the Atlantic Forest coast. Fishers include inhabitants of islands of the SE Atlantic Forest in Brazil. Data on fish landings were collected for different islands, in 1986 and 1989–1990, for species caught, technology used and fishing time. Fishing spots were marked or rechecked using GPS in 1997–1999. Fishing is performed in paddled, motorized canoes or in small boats with set gillnets or hook and line. Marine animals caught vary from place to place and include fish, shrimp, squid and crab. Spots used are very stable in time, since they did not change for about 10 years. Among other factors, technology limits the range of access of the fishers to the spots. An informal division of fishing areas or spots is observed, based on the locality of residence of the fishers. The mapping and observed division of fishing spots may be used in local management, helping to control the intrusion of industrial fishers in artisanal areas. Local rules and discrimination of spot users may be helpful for artisanal fishers, especially in areas where conflicts with trawlers occur. The observed long-term stability of the use of fishing spots by artisanal fishers and conflicts with other users indicate the urgency of considering local rules for conservation purposes in Atlantic Forest coastal areas. Electronic Publication  相似文献   
240.
The objective of this article is to illustrate the use of a framework to design a set of tools to assess progress towards improved well-being in a mining region. The framework uses an ecosystem approach to assess human well-being and is sensitive to the needs, concerns, and interests of at least the major stakeholders: government, company and community. The framework seeks to be useful to stakeholders and to be of policy relevance. The article presents the proposed framework with illustrations from a case study in Goa, India. Mining in Goa has had both positive and negative impacts on the well-being of local people. These impacts vary depending on the age of mining. In areas where mining is well established and active, the economic impacts are more positive. The social and environmental impacts are more negative in the regions where mining is new or is closing down. These characteristics generate their own set of issues of concern to stakeholders. Based on these issues, three types of tools to assess current well-being and progress towards improved well-being are suggested: (i) Indicators based on identified issues using the Pressure-State-Response (PSR) framework; (ii) A quality of life instrument, which can be developed either as an aggregate measure of well-being or in a more limited way to capture the satisfaction of the community with their living conditions; (iii) A regional income accounting framework to assess whether the mining region is able to continue functioning into the indefinite future without being forced into a decline through the degradation of its key natural, social, and human assets and resources. The article suggests that if these tools are used regularly, an information system will emerge that will, over time, provide markers of what mining is doing to the region and to the local communities.  相似文献   
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