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41.
This study examined the mental health outcomes of job stress among Chinese teachers in Hong Kong. A total of 269 Chinese teachers participated in Study 1 which provided cross‐sectional data regarding the associations among stress resource factors, burnout, and negative mental health. Study 2 was a six‐month longitudinal study which aimed to establish the direction of the associations among the hypothesized variables across two time points with a separate sample of 61 Chinese secondary school teachers. Results of the structural equation modelling analyses on the cross‐sectional data at T1 showed that stress resource factors of self‐efficacy and proactive attitude were negatively related to burnout, which in turn had a direct effect on negative mental health. Stress resource factors were also directly linked to mental health status of teachers. Results of similar analyses on the longitudinal data at T2 further indicated that burnout at T1 had a direct impact on burnout at T2, which in turn had a direct effect on negative mental health at T2. Findings and limitations of the study were discussed. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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“In contrast to other fields of politics, a few, minor measurements (indicators) are still lacking in the environmental policies which enable one to evaluate the environmental situation and to consequently take over a major role in political discussions” (BMU 1998). There are a multitude of suggestions for such environmental indicators on both a national and an international level. To date, however, there are still no indicators through which the ecological effects of biosphere pollution can be evaluated. This work provides two examples how biomonitoring data can be connected to environmental indicators. Based on the background concentrations of a multitude of heavy metals and dioxins/furans in two individual bioindicators (standardized grass and kale cultures), which have been combined to act as indicators for the topic in question, indices have been calculated through the determination of reference values. The results are indicators for the pollution effects of traffic-related emissions, the pollution effects from the emissions of fossil fuels and the pollution effects of dioxins and furanes. These indicators may still be combined further through the methods of calculation which are described. The further, methodical development of bioindicators, however, turned out to be problematic. Only data whose survey methods have been standardized to such an extent that the results are comparable with each other over longer periods of time can be combined to represent indicators: an inalienable requirement for the presentation of trends.  相似文献   
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The present study was performed to characterise in-stream pesticide exposure within the Palatinate vineyard region in south-west Germany, evaluate the influence of buffer strip widths and identify mitigation measures for the relevant entry pathways. In-stream water and sediment samples that were taken at nine sampling sites of different buffer widths following intense rainfall, and edge-of-field runoff that were sampled in erosion rills were analysed regarding 28 active ingredients of pesticides including copper. In-stream samples contained a mix of 8 ± 4 pesticide compounds, resulting in total pesticide concentrations of 1.4-8.9 μg l−1 for water and 16-670 μg kg−1 dw for sediment. Following an exceptional rainfall event with a previous 34-day drought period, pesticide concentrations reached 7.0-83.4 μg l−1. Fungicides were the most important pesticides found and were significantly correlated with the pesticide application frequency and rate. The calculated toxicity values per sample (TUmax) indicated that both organic pesticides and copper concentrations likely cause ecotoxicological effects in the field. The buffer strip width was of little importance for pesticide in-stream concentrations because pesticide entry occurred mainly via the field path network and erosion rills. Pesticide in-stream concentrations were significantly and positively correlated with the concentrations detected in erosion rills (R2 = 0.56). As possible risk mitigation measures, we suggest the implementation of grassed field paths and vegetated ditches or wetlands.  相似文献   
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Traffic related platinum deposits on, or near to, the roads. Platinum accumulation was studied using the method of standardised culture of grass (Lolium multiflorum) at locations with different traffic exposure in the region of Munich. Grass cultures from 6 locations with high traffic exposure, and 3 reference locations far away from traffic emissions, were analysed in 1992 and 1993. The results show a good indication of the platinum emissions byLolium multiflorum. The platinum concentrations rose with the increasing traffic. They diminished with growing distance from the verge of the road. The highest average platinum concentrations were measured at locations close to highly frequented urban roads, in the range 0.8 to 2.9 μg/kg dm. The average platinum concentration at locations far from emissions was found in the range of 0.17 to 0.51 μg/kg dm in 1992 and 1993. The good correlation between the platinum concentrations in grass cultures and the concentrations of other traffic-related elements, like antimony, chromium and lead, verifies the dependence of platinum accumulation from traffic.  相似文献   
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The working group on “boindication/assessment of effects” is made up of specialists active in the fields of bioindication and emission ecology for the German Federal administrative offices concerned with the protection of the environment and for the Geman Environmental Protection Agency. In April 1996, this working group adopted the recommendation for a “countrywide survey on the effects of emissions using bioindicatiors”. The goal of this national survey is to determine the geographic distribution and the development over time of such emissions, as well as to document the effects of background emissions. In order to achieve these goals, the development of national measuring networks and permanent observation stations is mandatory. A minimal demand of investigations and of investigative procedures is required in order to compare the results of the individual Federal States and to consequently combine these findings as an overall picture for the entire Federal Republic of Germany. Mosses and lichens are recommended for passive biological monitoring, while standardized grass cultures, kale, stinging nettle and tobacco are suggested for active biomonitoring. In addition, detailed methodical recommendations concerning the use of standardized grass cultures and kale are discussed.  相似文献   
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