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941.
Weekly work–school conflict,sleep quality,and fatigue: Recovery self‐efficacy as a cross‐level moderator
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This study employed a weekly diary method among a sample of 74 Midwestern college student workers in order to examine the within‐person relationships between work–school conflict, sleep quality, and fatigue over five weeks. Further, recovery self‐efficacy was proposed as a cross‐level moderator of the relation between sleep quality and fatigue. Results from multilevel analyses demonstrated that weekly work–school conflict was negatively related to weekly sleep quality and positively related to end‐of‐week fatigue, with sleep quality partially mediating the relation between work–school conflict and fatigue. These findings enhance understanding of the process by which work–school conflict contributes to college student workers' strain on a weekly basis. Additionally, student workers with low recovery self‐efficacy demonstrated a negative relation between sleep quality and fatigue; however, this relation did not exist for student workers with high recovery self‐efficacy. This finding suggests recovery self‐efficacy as an important resource that may reduce the association between poor sleep quality (as a result of work–school conflict) and fatigue. The current findings provide important theoretical and practical implications for researchers, organizations, and college institutions as a whole. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
942.
Are older workers more active copers? Longitudinal effects of age‐contingent coping on strain at work
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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
943.
Mohammed I. Haniff Raymond H. Zienius Cooper H. Langford Donald S. Gamble 《Journal of environmental science and health. Part. B》2013,48(2):215-262
Abstract The solution phase complexing equilibria of atrazine by fulvic acid at 25°C±1.° have been investigated over the pH range of 1.3 to 6.0. Experiments with 0.1MKC1 and chelated Cu(II) are compared with those without metal ions. The use of a fulvic acid having calibrated acidic and Cu(II) chelation properties has made it possible to obtain stoicheometricly “exact”; chemical information. This is correlated with previous hydrolysis kinetics work. It is concluded that atrazine is hydrogen bonded in a labile equilibrium, to an identifiable set of protonated carboxyl groups, which act as Brönsted acid catalysts for hydrolysis. 0.1M KC1 changes (1‐αA), the degree of protonation of the carboxyl groups, without otherwise affecting the atrazine complexing. Cu(II) chelation both reduces and weakens the complexing through a combination of carboxyl group blocking, and fulvic acid aggregation. Simple equations are presented for predictive calculations. 相似文献
944.
John W. Leung Barrie G.R. Webster 《Journal of environmental science and health. Part. B》2013,48(6):1169-1201
Abstract Radiolabelled end‐use mixtures of glyphosate with and without a cationic surfactant (Ethomeen® T/25) and an organosilicone surfactant (Silwet® L‐77) were applied onto trembling aspen (Populus tremuloids Michx.) leaves at the rate of 1.0 kg of AE (acid equivalent) in 35 L/ha area of foliage. A 5‐mm rainfall with an intensity of 10 mm/h was applied at intervals of 0.5, 8, 24, 36, 48, 72, and 96 h after treatment. Glyphosate washoff was determined by liquid scintillation counting of radioactivity in the rain‐washing. At 36 h post‐treatment, both the adjuvants significantly reduced glyphosate washoff (Ethomeen by 69.6% and Silwet by 59.7%) from foliage, compared to the washoff (82.6%) when Vision alone was applied without the adjuvants. Results on the rate of plant growth indicated that with a rain‐free period of 8 h or more, the growth of most seedlings was stunted within 1 or 2 d. Percentage of foliar browning 20 d after treatment with rain‐free period of 8 to 48 h ranged from 8 to 80% for Vision alone, 75 to 100% for Vision with Ethomeen, and 85 to 100% for Vision with Silwet, respectively. Physical properties of the end‐use mixtures were measured with and without the two adjuvants to examine droplet spreading and drying rates in relation glyphosate rainfastness. The Silwet adjuvant lowered the surface tension of the end‐use mixture, but Ethomeen did not. Droplets containing Silwet were spread more than those containing Ethomeen. However, the greater area of contact caused by Silwet did not contribute to a significant increase in the translocation rate of glyphosate into untreated parts of the seedlings, and showed no relationship with rainfastness of glyphosate deposits on trembling aspen. 相似文献
945.
Kate E. Griffiths Sharon T. Balding John B. Dickie Gwilym P. Lewis Tim R. Pearce Richard Grenyer 《Conservation biology》2015,29(2):370-381
Ex situ conservation efforts such as those of zoos, botanical gardens, and seed banks will form a vital complement to in situ conservation actions over the coming decades. It is therefore necessary to pay the same attention to the biological diversity represented in ex situ conservation facilities as is often paid to protected‐area networks. Building the phylogenetic diversity of ex situ collections will strengthen our capacity to respond to biodiversity loss. Since 2000, the Millennium Seed Bank Partnership has banked seed from 14% of the world's plant species. We assessed the taxonomic, geographic, and phylogenetic diversity of the Millennium Seed Bank collection of legumes (Leguminosae). We compared the collection with all known legume genera, their known geographic range (at country and regional levels), and a genus‐level phylogeny of the legume family constructed for this study. Over half the phylogenetic diversity of legumes at the genus level was represented in the Millennium Seed Bank. However, pragmatic prioritization of species of economic importance and endangerment has led to the banking of a less‐than‐optimal phylogenetic diversity and prioritization of range‐restricted species risks an underdispersed collection. The current state of the phylogenetic diversity of legumes in the Millennium Seed Bank could be substantially improved through the strategic banking of relatively few additional taxa. Our method draws on tools that are widely applied to in situ conservation planning, and it can be used to evaluate and improve the phylogenetic diversity of ex situ collections. Maximizar la Riqueza Filogenética de los Bancos de Semillas 相似文献
946.
Abstract: Non‐native species can cause the loss of biological diversity (i.e., genetic, species, and ecosystem diversity) and threaten the well‐being of humans when they become invasive. In some cases, however, they can also provide conservation benefits. We examined the ways in which non‐native species currently contribute to conservation objectives. These include, for example, providing habitat or food resources to rare species, serving as functional substitutes for extinct taxa, and providing desirable ecosystem functions. We speculate that non‐native species might contribute to achieving conservation goals in the future because they may be more likely than native species to persist and provide ecosystem services in areas where climate and land use are changing rapidly and because they may evolve into new and endemic taxa. The management of non‐native species and their potential integration into conservation plans depends on how conservation goals are set in the future. A fraction of non‐native species will continue to cause biological and economic damage, and substantial uncertainty surrounds the potential future effects of all non‐native species. Nevertheless, we predict the proportion of non‐native species that are viewed as benign or even desirable will slowly increase over time as their potential contributions to society and to achieving conservation objectives become well recognized and realized. 相似文献
947.
S.R. Tyagi K. Sriram Satya Narayan U.K. Misra 《Journal of environmental science and health. Part. B》2013,48(6):651-664
Abstract Administration of endosulfan significantly increased microsomal protein, cytochrome P‐450 content and the activity of aminopyrine N‐demethylase. Effect of endosulfan and actinomycin D either alone or together on microsomal protein, cytochrome P‐450, NADPH cytochrome c reductase, aniline hydroxylase, aminopyrine N‐demethylase, phosphatidylcholine content, incorporation of 3H‐choline and 14C‐methionine were studied in rats given amino acid deficient and supplemented diets. Administration of endosulfan significantly increased the above parameters in both the dietary groups, whereas administration of actinomycin D did not have any effect in rats fed supplemented diets, however, significant decrease in the PC and the incorporation of choline and methionine into PC of rats fed deficient diet were observed. A positive correlation in the effect of endosulfan on hepatic mixed function oxidase activity and hepatic phosphatidylcholine is observed. 相似文献
948.
Harry F. Lins Timothy A. Cohn 《Journal of the American Water Resources Association》2011,47(3):475-480
Lins, Harry F. and Timothy A. Cohn, 2011. Stationarity: Wanted Dead or Alive? Journal of the American Water Resources Association (JAWRA) 47(3):475‐480. DOI: 10.1111/j.1752‐1688.2011.00542.x Abstract: Aligning engineering practice with natural process behavior would appear, on its face, to be a prudent and reasonable course of action. However, if we do not understand the long‐term characteristics of hydroclimatic processes, how does one find the prudent and reasonable course needed for water management? We consider this question in light of three aspects of existing and unresolved issues affecting hydroclimatic variability and statistical inference: Hurst‐Kolmogorov phenomena; the complications long‐term persistence introduces with respect to statistical understanding; and the dependence of process understanding on arbitrary sampling choices. These problems are not easily addressed. In such circumstances, humility may be more important than physics; a simple model with well‐understood flaws may be preferable to a sophisticated model whose correspondence to reality is uncertain. 相似文献
949.
Abstract: Achieving multiple conservation objectives can be challenging, particularly under high uncertainty. Having agreed to limit seahorse (Hippocampus) exports to sustainable levels, signatories to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) were offered the option of a single 10‐cm minimum size limit (MSL) as an interim management measure for all Hippocampus species (≥34). Although diverse stakeholders supported the recommended MSL, its biological and socioeconomic implications were not assessed quantitatively. We combined population viability analysis, model sensitivity analysis, and economic information to evaluate the trade‐off between conservation threat to and long‐term cumulative income from these exploited marine fishes of high conservation concern. We used the European long‐snouted seahorse (Hippocampus guttulatus) as a representative species to compare the performance of MSLs set at alternative biological reference points. Our sensitivity analyses showed that in most of our scenarios, setting the MSL just above size at maturity (9.7 cm in H. guttulatus) would not prevent exploited populations from becoming listed as vulnerable. By contrast, the relative risk of decline and extinction were almost halved—at a cost of only a 5.6% reduction in long‐term catches—by increasing the MSL to the size reached after at least one full reproductive season. On the basis of our analysis, a precautionary increase in the MSL could be compatible with sustaining fishers' livelihoods and international trade. Such management tactics that aid species conservation and have minimal effects on long term catch trends may help bolster the case for CITES trade management of other valuable marine fishes. 相似文献
950.
This article reviews planning issues relating to “high‐tech” industry in Britain, and uses a case study of a manufacturer of micro‐computers in Oxford, England as a focus for a discussion. It concludes that town planning categories are not, in themselves, a constraint on high technology firms, and suggests that the provision of sites and premises by local authorities is a useful and undervalued task. 相似文献