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This article presents an evaluation and proposals for improving a method for assessing health and safety management systems. This method takes resilience engineering (RE) as its underlying philosophy and was originally devised and tested in a case study of a manufacturing plant. Four main changes were proposed in comparison with the original version of the method: (a) a framework for assessing the use of RE principles more systematically; (b) guidelines for developing an action plan as a result of the assessment; (c) re-organization of the data collection tools in order to increase their ease of use; and (d) procedures for facilitating the assignment of scores to the items assessed. The evaluation of the method, which was not restricted to the changes described in this article, was conducted based on seven criteria for evaluating safety assessment tools. Both the evaluation and the impact of the changes are discussed based on a case study, in which the method was applied in a company that distributes electricity.  相似文献   
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This study addresses coping processes as explanation of age‐related differences in strain experience. Based on the life‐span theory of control, we posit that older workers employ more active problem‐focused and more active emotion‐focused coping strategies than younger workers, which should mediate age effects on strain at work. The correlation between age and passive avoidance coping, in contrast, is expected to be qualified by external resources such as job control. Hypotheses were tested in a two‐wave panel study (8 months lag) with 634 workers (age range 16–65 years). Job demands were considered as control variables. As predicted, older as compared with younger workers reported more active problem‐focused coping, which mediated age differences on strain in the longitudinal analysis. No mediation was found for active emotion‐focused coping. Moreover, age‐contingent effects of passive avoidance coping were moderated by job control. When job control was low, younger as compared with older workers reported more avoidance coping, which in turn decreased strain in the longitudinal analysis. Finally, reverse longitudinal effects of age‐contingent strain on active problem‐focused and active emotion‐focused coping provide initial evidence for age‐contingent resource spirals. Together, the results reveal specific strengths of older workers for stress management at work. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Acute exposure to waterborne copper is followed by a reduction in heart rate in gastropod limpets. In order to understand the mechanism of this effect, exposure to copper (0.25 or 0.5 mg l(-1); for 3 and 6 h) was combined with an injection of tetrodotoxin (TTX, 20 microl, 0.5 or 1 microM), a natural toxin that inhibits the propagation and transmission of impulses in excitable tissues. Experiments were performed on the Mediterranean limpet Patella caerulea, using a non-invasive method for the recording of cardiac activity. TTX did not affect the bradycardic effect of the cholinergic agonist carbachol. However, this toxin significantly antagonized the bradycardia induced by 0.25 and 0.5mg l(-1) of copper exposure and prevented the acardia observed in some limpets exposed to 0.5mg l(-1) of copper for 6h. These results are consistent with the hypothesis that the inhibitory action of copper on limpet cardiac activity involves an extrinsic, cholinergic neuronal control.  相似文献   
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Journal of Material Cycles and Waste Management - In this work, the effectiveness of a rapid recycling method of waste polypropylene (WPP) with the addition of inorganic fillers was investigated....  相似文献   
148.
Meneses M  Schuhmacher M  Domingo JL 《Chemosphere》2002,46(9-10):1393-1402
The vegetation and soil levels of the 17 polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) toxic congeners were calculated by means of a vegetation and a soil model, respectively. Both models predicted the levels of the 17 PCDD/F congeners in quite good agreement with the observed results although the soil model was more accurate than the vegetation model. Four different pathways of contribution to the vegetation concentrations were taken into account: vapour-phase absorption, dry particle deposition, wet particle deposition and uptake by root. The most important pathway was the vapour-phase absorption and the less was the uptake by root. In the soils model four pathways were considered: background soil concentration, dry particle deposition, wet particle deposition and uptake by root. After the background concentration, the most important pathway was the wet deposition.  相似文献   
149.
A fuzzy expert system for soil characterization   总被引:1,自引:0,他引:1  
As soil is a natural resource not always renewable, the risk characterization of contaminated soils is an issue of great interest. Artificial Intelligence (AI), based on Decision Support Systems (DSSs), has been developed for a wide range of applications in contaminated soil management. Decision trees have already shown to be easy to interpret and able to treat large scale applications. Fuzzy logic gives an improvement in the perturbations and the variance of the training data, due to the elasticity of fuzzy set formalism. In this study, we have developed a classificatory tool applied to characterize contaminated soil in function of human and environmental risks. Knowledge engineering for constructing the Soil Risk Characterization Decision Support System (SRC-DSS) involves three stages: knowledge acquisition, conceptual design and system implementation. A total of 26 parameters were divided into three groups to facilitate the configuration of the expert system: source attributes, transfer vector attributes, and local properties. Sixteen case studies were evaluated with the SRC-DSS. In comparison with other techniques, the results of the current study have shown that SRC-DDS is an excellent tool to classify and characterize soils according to the associated risk.  相似文献   
150.
Spawning pattern (assessed by seasonal changes in ovarian developmental stages) and type of fecundity (assessed by analysis of oocyte-size frequency distributions) of the round herring Etrumeus teres were studied in relation to ovarian growth and seasonal changes in the gonadosomatic (GSI), hepatosomatic (HSI) and liposomatic (LSI) index as well as the somatic condition of spawners (CS) in a spawning ground of southern Japan. Except for summer, mature and recently spawned ovaries occurred all year round. Oogonia and primary oocytes were present in all ovaries, and cortical alveoli stage (CA) oocytes occurred in all mature, hydrated and partially spent (PS) females (PS: females containing post-ovulatory follicles). Before hydration, a clutch of larger yolked oocytes, undergoing synchronous growth (range 0.7–1.1 mm), was present in mature ovaries which was completely separated from a more heterogeneous clutch of oogonia, primary and secondary oocytes (<0.150 mm) and oocytes in the CA stage (range 0.15–0.60 mm). As vitellogenesis progressed, the yolked clutch increased in size but the CA oocytes remained arrested. The latter entered into the secondary growth phase when hydration started in the advanced batch. Ovarian growth was isometric in all developmental stages, validating the use of GSI, which showed a consistent monthly evolution among years. Spawning stopped in summer (July and August) and peaked in winter and spring. HSI correlated positively with GSI on both a monthly mean basis (r = 0.76) and individual fish basis (liver weight explained 67–83% of the variability in ovary weight when females were grouped into 1-unit GSI intervals) suggesting a significant role of liver in vitellogenesis. LSI and CS also showed marked seasonal changes peaking from summer to middle autumn. Overall results suggest that E. teres is a multiple spawner with a group-synchronous ovarian development and indeterminate annual fecundity, with the three processes linked to an isometric growth of the ovary. We propose that such a reproductive pattern is an adaptation to produce batches of large pelagic eggs through a protracted spawning season.  相似文献   
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