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631.
Illegitimate tasks, a recently introduced occupational stressor, are tasks that violate norms about what an employee can reasonably be expected to do. Because they are considered a threat to one's professional identity, we expected that the daily experience of illegitimate tasks would be linked to a drop in self‐esteem and to impaired well‐being. We report results of two daily diary studies, one in which 57 Swiss employees were assessed twice/day and one in which 90 Americans were assessed three times/day. Both studies showed that illegitimate tasks were associated with lowered state self‐esteem. Study 1 demonstrated that high trait self‐esteem mitigated that relationship. Study 2 showed that illegitimate tasks were associated with not only lowered state self‐esteem but also lower job satisfaction and higher anger and depressive mood, but not anger or job satisfaction remained elevated until the following morning. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
632.
Development of objective measurements is an important requirement for establishing performance-based standards for protective clothing used while handling pesticide. This study, the second in a two-part series, reports on the work completed to evaluate the performance of approximately 100 fabrics that are either used or have the potential to be used for garments worn by operators while applying pesticides. Part I, published separately, provides an overview of these issues and describes research undertaken to select a test chemical for use in subsequent studies. The goals of this study were first to develop a comprehensive approach to evaluate the performance of garments currently being used by pesticide operators, and second, to use the laboratory and field data in the development of performance specifications.  相似文献   
633.
1,4‐Dioxane remediation is challenging due to its physiochemical properties and low target treatment levels. As such, applications of traditional remediation technologies have proven ineffective. There are a number of promising remediation technologies that could potentially be scaled for successful application to groundwater restoration. Sustainable remediation is an important consideration in the evaluation of remediation technologies. It is critically important to consider sustainability when new technologies are being applied or new contaminants are being treated with traditional technologies. There are a number of social, economic, and environmental drivers that should be considered when implementing 1,4‐dioxane treatment technologies. This includes evaluating sustainability externalities by considering the cradle‐to‐grave impacts of the chemicals, energy, processes, transportation, and materials used in groundwater treatment. It is not possible to rate technologies as more or less sustainable because each application is context specific. However, by including sustainability thinking into technology evaluations and implementation plans, decisions makers can be more informed and the results of remediation are likely to be more effective and beneficial. There are a number sustainable remediation frameworks, guidance documents, footprint assessment tools, life cycle assessment tools, and best management practices that can be utilized for these purposes. This paper includes an overview describing the importance of sustainability in technology selection, identifies sustainability impacts related to technologies that can be used to treat 1,4‐dioxane, provides an approximating approach to assess sustainability impacts, and summarizes potential sustainability impacts related to promising treatment technologies. ©2016 Wiley Periodicals, Inc.  相似文献   
634.
Wastewater treatment facility (WWTF) closures are rare environmental remediation events; offering unique insight into contaminant persistence, long‐term wastewater impacts, and ecosystem recovery processes. The U.S. Geological Survey assessed the fate of select endocrine disrupting chemicals (EDC) in surface water and streambed sediment one year before and one year after closure of a long‐term WWTF located within the Spirit Creek watershed at Fort Gordon, Georgia. Sample sites included a WWTF‐effluent control located upstream from the outfall, three downstream effluent‐impacted sites located between the outfall and Spirit Lake, and one downstream from the lake's outfall. Prior to closure, the 2.2‐km stream segment downstream from the WWTF outfall was characterized by EDC concentrations significantly higher (α = 0.05) than at the control site; indicating substantial downstream transport and limited in‐stream attenuation of EDC, including pharmaceuticals, estrogens, alkylphenol ethoxylate (APE) metabolites, and organophosphate flame retardants (OPFR). Wastewater‐derived pharmaceutical, APE metabolites, and OPFR compounds were also detected in the outflow of Spirit Lake, indicating the potential for EDC transport to aquatic ecosystems downstream of Fort Gordon under effluent discharge conditions. After the WWTF closure, no significant differences in concentrations or numbers of detected EDC compounds were observed between control and downstream locations. The results indicated EDC pseudo‐persistence under preclosure, continuous supply conditions, with rapid attenuation following WWTF closure. Low concentrations of EDC at the control site throughout the study and comparable concentrations in downstream locations after WWTF closure indicated additional, continuing, upstream contaminant sources within the Spirit Creek watershed. ©2016 Wiley Periodicals, Inc.  相似文献   
635.
636.
The American Academy of Pediatrics recommends that women breastfeed because of improved health outcomes for mothers and children. Because maternal employment during the first year of the child's life has been identified as a reason for breastfeeding cessation, we develop and test a role‐theory‐based framework to explain women's continuation of breastfeeding after return to work (Study 1) and report results of an exploratory study linking breastfeeding at work with job attitudes and well‐being (Study 2). Applying survival analysis to a longitudinal dataset gathered by the Centers for Disease Control (Study 1), we identify pregnant women's perceived employer support for breastfeeding as a predictor of women's breastfeeding goal intentions. Supervisors' negative workplace remarks about breastfeeding related to an eightfold increase of women's likelihood to discontinue exclusive breastfeeding and perceived support for breastfeeding after return to work predicted exclusive breastfeeding continuation. Results of Study 2 suggest that women who return to work and continue breastfeeding experience more family‐to‐work conflict and overload than women who do not reconcile work and breastfeeding. Further, results of Study 2 provide preliminary evidence suggesting that perceptions of supervisor and coworker support for breastfeeding relate positively to general perceptions of organizational support and negatively to depressive symptoms. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
637.
Household waste prevention in England has been recognised in national strategy as a key component for future sustainable practice. To support the policy agenda, the Department of Environment, Food and Rural Affairs (Defra) in England has funded an extensive programme of fundamental research in the area. The specific research aim reported on here, in this Defra funded project, was to trial and assess methods for monitoring and evaluating approaches detailed in the National Resource and Waste Forum (NRWF)’s Household Waste Prevention Toolkit. The methods that formed the basis for the four research Objectives for the project were: using pilot and control areas (core Objective), tracking waste arisings, measuring specific activities and declared awareness and behaviour surveys. A primary objective of this research was to quantify the direct waste tonnage impacts of implementing a targeted household waste campaign in Dorset County, UK. A key performance indicator chosen for this assessment was the weight of waste collected at the kerbside from households. In an area where a waste prevention campaign is well planned and implemented then reductions in household waste arisings in pilot areas can be in the region of 2% per annum. This method for monitoring can be used, in the hands of an expert project team, to communicate to the public the direct benefits of waste prevention. It was found that there are a wide range of factors that need to be taken into account in the UK, and that these had hitherto been given little prominence, such as careful matching of pilot and control areas – this proved problematical in this research. However, a range of techniques used to support the methods, e.g. doorstepping surveys and focus groups could not show clear attributable waste prevention impacts but their findings could be used to direct new future messages to the public. The most successful and measurable campaign activities that were revealed by evaluation were: mail preference registrations, Home composting and doorstepping. An expert evaluation of all major methods found that no clear preference was revealed as to which were the most useful. None of the methods were judged very poor neither very good, all had major issues about their use. Tracking waste arisings and focus groups were assessed to be the best techniques in terms of input effort to output value. It is likely that waste prevention teams for household waste will need very careful training in the cost-effective use of the NRWF Toolkit before they are competent to apply it to a given place; the issues are more complex than were first thought.  相似文献   
638.
An environmental parameters study has examined the impact of indoor temperature (T) and relative humidity (RH) levels on formaldehyde (CH2O) concentrations inside two unoccupied research houses where the primary CH2O emitter is particleboard underlayment. The data were fit to a simple three-term, steady state model describing the T and RH dependence of CH2O concentration in a single compartment with a single CH2O emitter. The model incorporates an Arrhenius T dependence and a nonlinear RH dependence of the CH2O vapor concentration within the solid CH2O emitter. The RH dependence is based on Freundlich's theory of the adsorption of water vapor on solid surfaces. The model is used to estimate potential seasonal variation in CH2O concentrations under specified experimental conditions inside the research houses. The modeled results indicate six- to ninefold variation between 18°C, 20% RH and 32°C, 80% RH, simulating potential winter/summer conditions with minimal indoor climate control. In comparison, Indoor conditions ranging from 20°C, 30% RH to 26°C, 60% RH yielded approximate two- to fourfold fluctuations in CH2O concentration.

The research house data were also used to evaluate the limitations and applicability of more complex five-term models developed from small-scale chamber studies of the environmental dependence of CH2O emissions from particleboard underlayment. These models also incorporate a linear T and RH dependence of the CH2O transport rate through the CH2O emitter in addition to the T and RH dependence of the CH2O concentration within the emitter. Good correlation is observed between the results of the research house studies and 1) a selected (i.e., single) underlayment model over a broad range of environmental conditions and 2) a combined underlayment model over a restricted range of environmental conditions.  相似文献   
639.
Abstract

The effects of cadmium and lead on chronic mercury accumulation were investigated in O. aureus. After 140 days’ exposure the accumulation of mercury in the liver, brain, gill filaments, intestine, caudal muscle, spleen, trunk kidney and eye was analysed. The exposure concentrations were 0.05, 0.10 and 0.20 mg/L for mercury alone. O. aureus was also exposed to mixtures of 0.05 mg/L mercury with lead (0.05 mg/L and 0.50 mg/L or cadmium (0.05 mg/L) and 0.10 mg/L mercury with 0.10 mg/L cadmium. In food fish, a knowledge of toxic metal accumulation patterns is of great importance because of their contribution to the human diet and, as fishmeal, to the diet of agricultural animals. The trunk kidney consistently accumulated higher concentrations of mercury than any of the other tissues investigated.  相似文献   
640.
Paul Foley 《环境政策》2017,26(5):915-937
To contribute to the literature on transnational sustainability governance hybrids, a new fisheries certification program in Iceland that was originally developed as an alternative to the non-governmental Marine Stewardship Council is examined. While this new program appears on the surface to constitute a purely nationalistic reaction against external non-state authority, the new governance institution is also non-governmental and incorporates international norms and institutions. To explain this new governance hybrid, Robert Cox’s International Political Economy approach to production and power is engaged. This approach theorizes the co-constitution of the social forces of production, state–society complexes and global governance. It is argued that the Icelandic case is not entirely localized or unique; it is part of a broader movement in which social forces of production respond to new market-oriented transnational sustainability governance institutions by developing territorially embedded but transnationally legitimate alternatives.  相似文献   
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