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1.
Early non-invasive fetal sexing is widely available over the Internet, leading to concerns about its possible use for sex selection. The aim of this review is to summarise the results of surveys describing lay attitudes towards sex selection for non-medical reasons to help address or inform such concerns. A search of electronic databases and key journals was supplemented by an Internet search and citation-tracking. Twenty-one quantitative studies were identified. Most were conducted in the US, with five recent studies in the UK and Germany. Most studies found that, overall, people were not in favour of sex selection. However, this varied from 94 to 18%. People may hold more negative attitudes when the method of sex selection is specified, particularly if this involves termination of pregnancy (TOP). Attitudes towards the general availability of sex selection are less negative than those towards personal use. Attitudes were consistently negative in German surveys. Little is known of such attitudes outside the US, the UK and Germany, and how such attitudes may change as new sex selection technologies become available. Studies of use of early non-invasive fetal sexing for sex selection for non-medical reasons are needed to assess the extent to which concerns about usage are justified and to assist in debates on how these might be most appropriately addressed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
2.
BACKGROUND, AIM AND SCOPE: Conjoint analysis and the related choice-modelling methods have been used for many years in marketing research to evaluate consumer behaviour and preferences for different kinds of product attributes. Recently, the number of applications in environmental science and management has started to grow. Conjoint analysis is found in many different forms, and the environmental studies evaluated in this review display the same range of methods as in other fields. The key characteristic of all these methods is that trade-offs are evaluated by jointly considering a number of important attributes. MAIN FEATURES: This paper is a review of the literature on environmental applications of conjoint analysis and assesses in which environmental area conjoint analysis has been most successful. The method and the design of the studies are reviewed as well. RESULTS: A total of 84 studies were found, dealing with environmental issues that were evaluated by conjoint analysis. The studies concern agriculture, ecosystem management, energy, environmental evaluation, forestry, land management, pollution, products, recreation, environmental risk analysis and waste management. DISCUSSION: Choice experiments seem to have a comparatively stronger position in environmental studies than elsewhere. Most of the environmental applications are related to natural resource management. This is somewhat surprising, but a number of reports have appeared also on product evaluation, which could be a key application area in the future. CONCLUSIONS: Compared to marketing and transportation, the number of environmental conjoint studies is rather small but increasing, and the method has proven to work effectively in eliciting preferences on environmental issues. In environmental issues, experimenters often use choice experiments, especially concerning ecosystem management and environmental evaluations. When it comes to evaluating preferences concerning agriculture, forestry, energy and products, a more traditional approach of conjoint analysis is favoured. RECOMMENDATIONS AND PERSPECTIVES: Two new areas of application are identified in this review--environmental communication and expert elicitation. Conjoint analysis can thus be developed into a useful instrument for environmental risk analysis and communication, both of which are necessary for an efficient approach to risk governance.  相似文献   
3.
Simmonds S  Cuttst F  Dick B 《Disasters》1985,9(1):61-69
Many problems have been encountered in the planning and implementation of health care in refugee camps, and more specifically in the training of refugees as primary health care workers. A review of the published literature and a "survey" of the opinions and experiences of refugee, national and international health personnel regarding training has therefore been undertaken to provide an overview of what has been done and to make recommendations for future work.
The review highlights the need to reallocate resources away from high visibility emergency aid to development activities, such as training, that will create an infrastructure for primary health care and promote self-reliance.  相似文献   
4.
水体中酚类化合物分光光度分析方法的研究   总被引:4,自引:3,他引:4  
对国内外水体中酚类化合物现有的分光光度分析方法进行了文献综述 ,内容包括可见光分光光度法、紫外光分光光度法、荧光分光光度法和流动注射分光光度法。在总结归纳的基础上 ,提出了水体中酚类化合物分光光度分析方法的发展方向。  相似文献   
5.
城市环境质量定量评价方法   总被引:5,自引:0,他引:5  
文章基于对于城市环境质量的评价方法的研究,阐述了各类评价方法的优缺点,着重介绍了物元模型、投影寻踪评价法、神经网络、遗传算法优化神经网络四种定量评价方法,并介绍了各类方法在城市环境质量评价中的应用现状.  相似文献   
6.
在以工期考虑为重点的V-3002B液化气球罐内外部检验过程中,引用现代管理中网络计划技术关键路线法,为加快芳烃厂压力容器检验提供了科学的依据。本文总结和介绍了网络计划技术在芳烃厂贮运车间V-300亚球罐内外部检验过程应用情况。  相似文献   
7.
2002年我国事故与灾害状况综述   总被引:3,自引:36,他引:3  
本对我国2002年的安全生产事故及自然灾害情况进行了总结和评述。包括火灾(城乡火灾、森林火灾、草原火灾)、天气气候特征、农业自然灾害(干旱、洪涝、风雹、低温冻害)、海洋灾害(风暴潮、赤潮、海浪)、地质灾害(地震、泥石流、水土流失)等。  相似文献   
8.
典型高原山地城市环境空气质量预报预警平台设计   总被引:2,自引:1,他引:1  
邓聪  王健  向峰  邱飞 《中国环境监测》2017,33(5):95-100
空气质量预报系统作为一种重要的工具用于为公众提供空气质量预报信息、评估城市空气质量,为污染控制战略、动态环境管理以及决策制定提供支持。研究对国内外环境空气质量预报现状进行了回顾,以云南省为例提出了高原山地城市环境空气质量预报预警体系建设的整体思路,针对系统建设现状,提出了环境空气质量预报预警系统建设所面临的问题以及对未来发展方向的建议。  相似文献   
9.
为建立考虑地层和套管参数随机性的套管可靠度评价理论方法,以便得到复杂井况下套管传统设计安全系数与可靠指标之间的关系,提出了非均匀地应力和内压联合作用下,沿套管最大外挤力方向管壁任意位置发生屈服失效时外壁等效均匀外挤力的计算方法;建立了套管抗挤和抗内压三轴强度计算公式以及有效内压计算方法;根据套管载荷和强度影响因素统计参数以及评价过程中参数测试标准值,利用蒙特卡洛法(MC)建立了完整的套管可靠度计算和评价方法;通过实例对传统安全系数与可靠指标的对应关系进行了研究。研究结果表明:指定条件下,套管安全系数与可靠指标之间存在对应关系;利用建立的方法编制计算程序可以为传统设计法中安全系数代表的安全程度进行量化;可靠度评价方法能够为安全系数的选取提供指导。  相似文献   
10.
绿色发展是我国"十三五"时期五大发展理念之一,是解决我国发展与保护矛盾的根本途径。系统动力学是模拟宏观社会经济发展趋势和政策效力的常用分析工具,本文对系统动力学在中国区域绿色发展政策仿真中的应用进行了梳理。研究显示:系统动力学应用的区域范围方面,该方法全面应用于从国家直至县域等各个尺度的区域绿色发展研究,区域绿色发展通常被分解为经济、社会、资源、环境等子系统;应用的主要领域方面,水土资源、能源、水环境、固废治理、绿色产业等领域应用较多,大气环境、绿色消费等领域应用相对较少;方法的改进和完善方面,软系统分析法、各类优化方法和地理信息系统与系统动力学的集成应用日益普遍。文末根据文献梳理情况,提出未来应在决策变量设计、历史数据挖掘、环境系统对经济系统的反馈等方面进行方法改进。  相似文献   
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