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201.
Work-contingent self-esteem (WCSE; the degree to which workers' self-esteem is based on workplace performance) has positive consequences for performance, yet less is known about its consequences for well-being. In this paper, we contribute to the literature on WCSE by examining the mechanisms through which it impacts well-being at work and outside of work. We challenge contingent self-esteem (CSE) theory (Crocker & Park, 2004), which argues that CSE negatively impacts well-being by fostering internally controlled (introjected) motivation and diminishing autonomous motivation, by suggesting that WCSE fosters autonomous and internally controlled motivation and thus has both beneficial and harmful effects on well-being. We also expand CSE theory by suggesting that WCSE can negatively impact well-being outcomes by causing work–nonwork conflict. Results from a time-separated design in a sample of full-time employees supported our arguments, revealing that WCSE impacted well-being at work through both autonomous and internally controlled work motivations. WCSE also had negative effects on well-being at and outside of work through work–nonwork conflict. The beneficial effects of WCSE outweighed its harmful effects on job satisfaction and neutralized its harmful effects for all other outcomes. We discuss theoretical implications for CSE theory, self-determination theory, and work–nonwork issues and note important practical implications.  相似文献   
202.
The aim of this study was to develop a fugacity-based analysis of the fate of selected industrial compounds (alkylphenols and phthalates) with endocrine disrupting properties in a conventional activated sludge wastewater treatment plant (WWTP A) in South East Queensland, Australia. Using mass balance principles, a fugacity model was developed for correlating and predicting the steady-state-phase concentrations, the process stream fluxes, and the fate of four phthalates and four alkylphenols in WWTP A. Input data are the compound's physicochemical properties, measured concentrations and the plant's operating design and parameters. The relative amounts of chemicals that are likely to be volatilized, sorbed to sludge, biotransformed, and discharge in the effluent water was determined. Since it was difficult to predict biotransformation, measured concentrations were used to calibrate the model in terms of biotransformation rate constant. Results obtained by applying the model for the eight compounds showed <40% differences between most of the estimated and measured data from WWTP A. All eight compounds that were modelled in this study had high removal efficacy from WWTP A. Apart from benzyl butyl phthalate and bisphenol A, the majority is removed via biotransformation followed by a lesser proportion removed with the primary sludge. Fugacity analysis provides useful insight into compound fate in a WWTP and with further calibration and validation the model should be useful for correlative and predictive purposes.  相似文献   
203.
This study aimed at relating the variability of Ni biogeochemistry along the ultramafic toposequence to pedogenesis and soil mineralogy. Hypereutric Cambisols dominate upslope; Cambic Vertisols and Fluvic Cambisols occur downslope. The soil mineralogy showed abundance of primary serpentine all over the sequence. It is predominant upslope but secondary smectites dominate in the Vertisols. Free Fe-oxides are abundant in all soils but slightly more abundant in the upslope soils. Whereas serpentines hold Ni in a similar and restricted range in every soil (approx. 0.3 %), Ni contents in smectites may vary a lot and Mg-rich and Al-poor smectites in the Vertisol could hold up to 4.9 % Ni. Ni was probably adsorbed onto amorphous Fe-oxides and was also exchangeable in secondary smectites. High availability of Ni in soils was confirmed by DTPA extractions. However, it varied significantly along the toposequence, being higher in upslope soils, where Ni-bearing amorphous Fe-oxides were abundant and total organic carbon higher and sensibly lower downslope on the Vertisols: NiDTPA varied from 285 mg kg?1 in the surface of soil I (upslope) to 95.9 mg kg?1 in the surface of Fluvic Cambisols. Concentration of Ni in Alyssum murale shoots varied from 0.7 % (Hypereutric Cambisols) to 1.4 % (Hypereutric Vertisol). Amazingly, Ni uptake by A. murale was not correlated to NiDTPA, suggesting the existence of specific edaphic conditions that affect the ecophysiology of A. murale upslope.  相似文献   
204.
Natural protected areas (NPA) are portions of the Mexican territory where the original environment has not been modified and which are protected in order t  相似文献   
205.
The information presented in this paper is directed to those with the responsibility of designing and operating air quality monitoring networks. An analytical model for location of monitor sites based upon maximizing a sum of coverage factors for each source is developed. An heuristic solution method from the facilities location analysis literature is used for solution of the model. Results of an example problem are presented and compared with the monitoring network currently In place. The model is shown to be a valuable addition to the methods available to the air quality monitor network designer. Needs for further research are pointed out.  相似文献   
206.
207.
An instrumented single engine aircraft is being used to characterize plumes from large emission sources. By cross sectioning these plumes at a number of points we hope to describe the character and concentration of pollution as it ages and travels downwind under known meteorological conditions. This paper reports experimental work thus far completed on aerosol measurement. Flights have been made through plumes from a large coal-fired power station, forest fires, and a gravel plant. Particle counts in various size classifications were made with a Bausch and Lomb 40–1 Dust Counter which was carried in the aircraft. Selected meteorological parameters were recorded. Results show the aerosol concentrations in various size classifications that are found at successive distances downwind from these sources for distances up to 32 miles. Background aerosol concentrations are also reported, and variations in these can be noted with respect to time, location and altitude.  相似文献   
208.
ABSTRACT

Guidance for the performance evaluation of three-dimensional air quality modeling systems for particulate matter and visibility is presented. Four levels are considered: operational, diagnostic, mechanistic, and probabilistic evaluations. First, a comprehensive model evaluation should be conducted in at least two distinct geographical locations and for several meteorological episodes. Next, streamlined evaluations can be conducted for other similar applications if the comprehensive evaluation is deemed satisfactory. In all cases, the operational evaluation alone is insufficient, and some diagnostic evaluation must always be carried out. Recommendations are provided for designing field measurement programs that can provide the data needed for such model performance evaluations.  相似文献   
209.
Polygodial is a drimane sesquiterpene dialdehyde derived from certain terrestrial plant species that potently inhibits ascidian metamorphosis, and thus has potential for controlling fouling ascidians in bivalve aquaculture. The current study examined the effects of polygodial on a range of biochemical biomarkers of oxidative stress and detoxification effort in the gills of adult Perna canaliculus Gmelin. Despite high statistical power and the success of positive controls, the antioxidant enzymes glutathione reductase (GR), glutathione peroxidase (GPOX), catalase (CAT), and superoxide dismutase (SOD); thiol status, as measured by total glutathione (GSH-t), glutathione disulphide (GSSG), and GSH-t/GSSG ratio; end products of oxidative damage, lipid hydroperoxides (LHPO) and protein carbonyls; and detoxification pathways, represented by GSH-t and glutathione S-transferase (GST), were unaffected in the gills of adult P. canaliculus exposed to polygodial at 0.1 or 1 × the 99% effective dose in fouling ascidians (IC99). Similarly, GR levels, thiol status, and detoxification activities were unaffected in mussels exposed to polygodial at 10 × the IC99, although GPOX, CAT, and SOD activities increased. However, the increases were small relative to positive controls, no corresponding oxidative damage was detected, and this concentration greatly exceeds effective doses required to inhibit fouling ascidians in aquaculture. These findings compliment a previous study that established the insensitivity to polygodial of P. canaliculus growth, condition, and mitochondrial functioning, providing additional support for the suitability of polygodial for use as an antifouling agent in bivalve aquaculture.  相似文献   
210.
Fires in agricultural ecosystems emit greenhouse gases and aerosols that influence climate on multiple spatial and temporal scales. Annex 1 countries of the United Nations Framework Convention on Climate Change (UNFCCC), many of which ratified the Kyoto Protocol, are required to report emissions of CH4 and N2O from these fires annually. In this study, we evaluated several aspects of this reporting system, including the optimality of the crops targeted by the UNFCCC globally and within Annex 1 countries, and the consistency of emissions inventories among different countries. We also evaluated the success of individual countries in capturing interannual variability and long-term trends in agricultural fire activity. In our approach, we combined global high-resolution maps of crop harvest area and production, derived from satellite maps and ground-based census data, with Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) measurements of active fires. At a global scale, we found that adding ground nuts (e.g., peanuts), cocoa, cotton and oil palm, and removing potato, oats, rye, and pulse other from the list of 14 crops targeted by the UNFCCC increased the percentage of active fires covered by the reporting system by 9%. Optimization led to a different recommended list for Annex 1 countries, requiring the addition of sunflower, cotton, rapeseed, and alfalfa and the removal of beans, sugarcane, pulse others, and tuber-root others. Extending emissions reporting to all Annex 1 countries (from the current set of 19 countries) would increase the efficacy of the reporting system from 6% to 15%, and further including several non-Annex 1 countries (Argentina, Brazil, China, India, Indonesia, Thailand, Kazakhstan, Mexico, and Nigeria) would capture over 55% of active fires in croplands worldwide. Analyses of interannual trends from the United States and Australia showed the importance of both intensity of fire use and crop production in controlling year-to-year variations in agricultural fire emissions. Remote sensing provides an effective means for evaluating some aspects of the current UNFCCC emissions reporting system; and, if combined with census data, field experiments and expert opinion, has the potential to improve the robustness of the next generation inventory system.  相似文献   
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