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51.
The link between teamwork and job satisfaction was investigated in a sample of 48 manufacturing companies comprising 4708 employees. Two separate research questions were addressed. First, it was proposed that supervisor support would be a weaker source of job satisfaction in companies with higher levels of teamworking. Multilevel analysis indicated that the extent of teamwork at the company level of analysis moderated the relationship between individual perceptions of supervisor support and job satisfaction. Second, it was proposed that the extent of teamwork would be positively related to perceptions of job autonomy but negatively related to perceptions of supervisor support. Further, it was proposed that the link between teamwork and job autonomy would be explained by job enrichment practices associated with teamwork. Analyses of aggregated company data supported these propositions and provided evidence for a complex mediational path between teamwork and job satisfaction. Implications for implementing teamwork in organizations are discussed. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
52.
The approach, methods, data, and results set out by Crocker et al.1 in their study of the effect and valuation of air pollution on human morbidity are examined in detail. It is found that there are severe deficiencies in both method and data which make the results of extremely doubtful value for the purposes of policy formulation.  相似文献   
53.
Sex allocation is an important reproductive decision for parents. However, it is often assumed that females have substantial control over sex allocation decisions, and this is particularly true in haplodiploid insects, in which females apparently determine sex by deciding whether to fertilise an egg (and produce a diploid daughter) or not (and produce a haploid son). Mechanisms by which males may influence sex allocation are not so straightforward, and their potential influence on sex ratios has been somewhat neglected. Here, we test whether males influence offspring sex ratios in the parasitoid wasp Nasonia vitripennis. We show that some of the variation in observed sex ratios can be attributed to males when comparing the affect of male strain on sex ratio. We did not find among-male variation in sex ratio with a less powerful experiment using males from only one strain or an effect of male mating environment. Our data suggest that males can influence female sex ratios and contribute to the variation around the sex ratios optimal for females. However, the influence is not large, suggesting that females have more influence on sex allocation than do males. We conclude by considering whether male influences on sex ratio represent differences in male reproductive competence or deliberate attempts by males to increase their fitness by influencing daughter production.  相似文献   
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Epignathi are unusual congenital tumours presenting as oropharyngeal masses, often resulting in rapid asphyxia following birth. Occasionally, intracranial extension of the tumour is present, and two such cases are described. The presence of this complication, diagnosable by ultrasound examination, indicates that aggressive surgical treatment is inappropriate.  相似文献   
57.
Hazard mitigation planners claim that foresighted present actions and investments produce significant future benefits. However, they have difficulty in supporting their claims, since previously their evidence typically was derived from individual case studies. Constituents and decision makers are often sceptical, believing that individual cases are either inapplicable to their situation or non-randomly selected to support a particular view. Planners need objective evidence based on a large body of experience to support the case for mitigation. Such is the unique contribution of a recent U.S. study that found that each dollar spent in three federal natural hazard mitigation grant programs (the Hazard Mitigation Grant Program, Project Impact, and the Flood Mitigation Assistance Program) saves society an average of $4 in future avoided losses. Complementing the aggregate benefit-cost analysis with community-based evaluations, the study yielded insights on how planners can improve long-term community resilience in the face of extreme events. Valuable lessons for mitigation planners and policy makers emerged: the need to consider a wide variety of losses, the importance of mixing qualitative with quantitative analysis, the value of averaging results over a large number of projects, and the need to more explicitly address social issues and data collection in order to reduce vulnerability and enhance resilience to cope with twenty-first century hazards.  相似文献   
58.
We develop and study multiplicity adjustments for low-dose inferences in environmental risk assessment. Application is intended for risk analysis studies where human, animal, or ecological data are used to set safe levels of a hazardous environmental agent. A modern method for making inferences in this setting is known as benchmark analysis, where attention centers on the dose at which a fixed benchmark level of risk is achieved. Both upper confidence limits on the risk and lower confidence limits on the “benchmark dose” are of interest. In practice, a number of possible benchmark risks may be under study; if so, corrections must be applied to adjust the limits for multiplicity. In this note, we discuss approaches for doing so with continuous, nonquantal response data.  相似文献   
59.
This report describes the application of palladized iron (Pd/Fe) to the dechlorination of polychlorinted biphenyls (PCBs) at ambient temperature. Experiments supported by congener-specific analyses demonstrated that dechlorination occurs in a step-wise fashion with the meta-chlorines being more reactive than ortho-chlorines. Over the course of the laboratory experiments, complete conversion to biphenyl was observed. The process was also tested with PCBs dissolved in high (40-60%) concentrations of ethanol and isopropanol as a means of simulating solutions generated by commercial soil and solid waste extraction processes. The reaction rate was sensitive to the percentage of solvent but complete dechlorination was still indicated. Tests with soil extracts from a contaminated site demonstrated that there were no apparent interferences from asphalt and other miscellaneous debris. Short-duration tests with highly contaminated PCB solutions from a hazardous waste site demonstrated efficient dechlorination although there was a reduction in reaction rate with time.  相似文献   
60.
A new method for evaluating biodegradability of starch-based and certain other polymer blends uses the pre- and postexposure stable carbon isotope composition of material coupled with weight loss data to determine which components have degraded. The naturally occurring stable isotope of carbon.13C, is enriched in corn starch (13C, approx. –11) compared to petroleum-derived synthetic polymers (13C, approx. –32). Results on starch-synthetic polymer blends indicate that the 13C signatures of these blends are near-linear mixtures of their component 13C. Values of a 13C for starch-synthetic polymer blends exposed to biologically active laboratory soil and artificial seawater conditions are depleted in13C compared to unexposed samples, suggesting loss of the starch component. Combined with weight loss data for the exposed samples, the 13C values are statistically consistent with models requiring loss of the soluble component glycerin, followed by loss of starch, then petrochemical polymer, or simultaneous loss of starch and petrochemical polymer. Replicate 13C analyses of starch-synthetic polymer blends increase the statistical power of this relatively inexpensive, accessible technique to discriminate between degrading components.  相似文献   
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