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91.
We investigate a long‐standing methodological rule of thumb, the idea that the frequency of absenteeism from work approximates an expression of voluntary behavior while total time lost better reflects involuntary behavior and ill health. Conducting original meta‐analyses and using results from existing meta‐analyses, we determine that time lost and frequency are equally reliable, that the relationship between them approximates unity when corrections for measurement artifacts are applied, and that there is very little evidence for differential criterion‐related validity predicated on the voluntariness distinction. We supply new meta‐analytic estimates of the reliability of absenteeism adjusted for aggregation period and determine that most extant meta‐analyses of the correlates of absenteeism have markedly under‐corrected for unreliability. Our results question the basic construct validity of the time lost–frequency distinction, and they contradict the practice of using “trigger points” that factor absence frequency into attendance monitoring and associated discipline systems so as to discourage short‐term absenteeism, assumed to be volitional. We conclude that the idea that time lost and frequency reflect different degrees of voluntariness is an unsupported urban research legend. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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In two recently published reports, hazards posed by dietary exposure to organophosphate and neonicotinoid plant protection products on the European honey bee (Apis mellifera L.) in Egypt were investigated. Using concentrations reported in those studies, an assessment of hazards posed by these two classes of insecticides to humans due to consumption of Egyptian honey from the Nile Delta during both spring and summer was performed. Twenty-eight compounds including metabolites were assessed for exposure of adult Egyptians based on the best- and worst-case scenarios. Even for the worst-case scenario, exposure to these two classes of pesticides in honey was 15-fold less than hazard index value of 1.0 for adverse effects on humans. Based upon this analysis, people exposed to these insecticides through consumption of honey products would be unlikely to exhibit adverse health outcomes.  相似文献   
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Environmental Science and Pollution Research - A novel marine fungus was isolated and classified as Aspergillus flavus strain EGY11. The heat-inactivated form of isolated Aspergillus flavus was...  相似文献   
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An evaluation of ~250 samples of groundwater in the Amman Zarqa Basin for selenium along with other major and trace elements showed that concentrations of Se ranged between 0.09 and 742 μg/L, with an average value of about 24 μg/L. Selenium concentrations exceeded the recommended threshold for drinking water of the World Health Organization (WHO; 10 μ/L of Se) in 114 samples, with greater than 50 μg/L (quantity equivalent to the Jordanian standard of the allowed concentration of the element in water) of Se in nine cases. The average concentrations of Se in the lower, middle, and upper aquifers of the basin were 3.41, 32.99, and 9.19 μg/L, respectively. Based on the correlation with geologic formations and the statistical analysis of major/minor constituents and Piper tri-linear diagrams, we suggest that carbonate/phosphate dissolution, oxidation–reduction processes, and fertilizers/irrigation return flow are, together, the primary factors affecting the chemistry of the groundwater. Factor analysis helped to define the relative role of limestone-dolomitic dissolution in the aquifers (calcium, magnesium, and bicarbonate), agricultural activities (sulfate, nitrates, phosphorus, and potassium), oxidation–reduction factor (Eh, Fe, Mn, Cu, Zn, and Se), and anthropogenic (industrial) factor (EC, Fe, Cr, Co, Zn, and As). The high variability in Se concentrations might be related to the possibility of a multi-source origin of Se in the area.  相似文献   
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Journal of Material Cycles and Waste Management - The recycling potential of water treatment plant (WTP) sludge in asphalt concrete mixes as filler material was assessed in this study. Marshall...  相似文献   
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Environmental Science and Pollution Research - Cities are growing worldwide with an increase in stormwater quantity and decrease in quality, negatively impacting receiving water bodies. The...  相似文献   
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A new use for biofilm barriers was developed and successfully applied to treat nitrate‐contaminated groundwater down to drinking water standards. The barrier was created by stimulating indigenous bacteria with injections of molasses as the carbon donor and a combination of yeast extract and trimetaphosphate as nutrients. This injection of amendments results in bacterial growth in the aquifer, which attaches to the sand grains to create a reactive semipermeable biofilm. The biofilm barrier presented in this article reduced the migration of contaminants and provided an active zone for remediation. The cylindrical biobarrier was constructed using eight wells on the perimeter forming a 60‐foot‐diameter reactive biodenitrification region. Another well at the center was installed to continuously extract the treated water. The intent was to produce a continuous source of nitrate‐free water. The system operated for over one year, and during this period, the biobarrier was revived multiple times by reinjecting molasses in the perimeter wells. Nitrate concentrations of treated water decreased from 275 mg/L (as nitrogen) to < 1 mg/L. © 2005 Wiley Periodicals, Inc.  相似文献   
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