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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   
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Two techniques are presented for estimation of natural animal populations, both of which may incorporate the effect of pollutants on populations. Both techniques assume specific underlying population dynamics which may not be applicable to certain species or ecosystems. However, both techniques allow for testing the hypothesis that the population dynamics specified is applicable. The techniques are used to criticize two recent empirical investigations of fisheries.  相似文献   
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Using a combination of soil, land use and geological information, a map of Great Britain has been derived which indicates the sensitivity of surface waters to acidification. For the geological information, a slightly modified version of an available map was used which indicated the sensitivity of groundwaters to acidification. For soils, 1-km databases of soil information for England and Wales and for Scotland were employed to map the soil sensitivity as determined by buffering capacity. The derived soils map was modified to take account of agricultural liming in arable and managed grassland areas using the ITE Land Classification. The final map of surface water sensitivity was obtained by using a geographic information system overlay procedure which enabled each combination of soil and geology sensitivity to be uniquely defined. The final sensitivity classification was based upon expert knowledge and the experience of a similar sensitivity mapping exercise for Wales.  相似文献   
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The paper describes a programme to develop the profile of major accident risk across a large multi national oil company. It describes the concepts, tools and processes for constructing the risk profile and some of the key learnings from the exercise.  相似文献   
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The controlled pyrolysis of polyethylene/polypropylene/polystyrene mixed with brominated high-impact polystyrene containing decabromodiphenyl ether as a brominated flame-retardant with antimony trioxide as a synergist was performed. The effect of decabromodiphenyl ether and antimony trioxide on the formation of its congeners and their effect on distribution of pyrolysis products were investigated. The controlled pyrolysis significantly affected the decomposition behavior and the formation of products. Analysis with gas chromatograph with electron capture detector confirmed that the bromine content was rich in step 1 (oil 1) liquid products leaving less bromine content in the step 2 (oil 2) liquid products. In the presence of antimony containing samples, the major portion of bromine was observed in the form of antimony bromide and no flame-retardant species were found in oil 1. In the presence of synergist, the step 1 and step 2 oils contain both light and heavy compounds. In the absence of synergist, the heavy compounds in step 1 oil and light compounds in step 2 oils were observed. The presence of antimony bromide was confirmed in the step 1 oils but not in step 2 oils.  相似文献   
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PROBLEM: Injuries resulting from lifting are costly, and create significant pain and discomfort. While engineering controls are the most effective means of reducing risks, most organizations continue to rely on manual lifting techniques. The problem, however, is that the use of safe-lifting techniques is inconsistent and managers have a difficult time motivating use of these techniques. Consequently, it is important to understand the factors driving safe-lifting behaviors. METHODS: This study used a survey to apply the theory of planned behavior (Ajzen., I., 1991. The theory of planned behavior. Organization Behavior and Human Processes, 50, 179-211) to safe-lifting among 136 materials management employees at a heavy manufacturing organization. Structural equation modeling and factor analysis were employed to analyze relationships among constructs. RESULTS: Results revealed that perceived behavioral control and intention were the strongest predictors of safe-lifting behavior. Subjective norms, to a lesser degree, were also important influences on intention. Attitudes did not surface as effective direct predictors of safe-lifting behavior, but did affect behavior and intent via mediating factors (subjective norms and perceived behavioral control). Finally, the theory of planned behavior was supported as an effective model explaining safe-lifting behavior, and had potential application for many other safety-related behaviors. IMPACT ON INDUSTRY: Results from this study emphasize the importance of perceived behavioral control as a factor associated with safety-related behavior.  相似文献   
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