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991.
Sleeping with a broken promise: The moderating role of generativity concerns in the relationship between psychological contract breach and insomnia among older workers 下载免费PDF全文
Patrick Raymund James M. Garcia Prashant Bordia Simon Lloyd D. Restubog Valerie Caines 《组织行为杂志》2018,39(3):326-338
This paper examines the relationship between psychological contract breach and insomnia among older workers (aged 40 years and up). Drawing upon the conservation of resources theory, we conceptualize breach as a stressful event characterized by a perceived threat, failure to gain, or actual loss of valued resources, which increases psychological distress and insomnia. Moreover, we hypothesized that older workers' generativity concerns would act as a personal resource that would buffer the negative impact of breach. We tested our proposed model in 2 studies (Study 1 = 123; Study 2 = 168) of employee–spouse dyads. Results revealed that psychological distress mediated the relationship between psychological contract breach and insomnia. These mediated relationships were significant for those with low, but not for those with high levels of generativity concerns. These effects remained significant even after controlling for perceived organizational support (i.e., a social exchange mechanism). Theoretical and practical implications are discussed. 相似文献
992.
Henry N.N. Bulley James W. Merchant David B. Marx John C. Holz Aris A. Holz 《Journal of the American Water Resources Association》2007,43(3):605-621
Abstract: The U.S. Environmental Protection Agency is charged with establishing standards and criteria for assessing lake water quality. It is, however, increasingly evident that a single set of national water quality standards that do not take into account regional hydrogeologic and ecological differences will not be viable as lakes clearly have different inherent capacities to meet such standards. We demonstrate a GIS‐based watershed classification strategy for identifying groups of Nebraska reservoirs that have similar potential capacity to attain a certain level of water quality standard. A preliminary cluster analysis of 78 reservoirs was performed to determine the potential number of Nebraska reservoir groups. Subsequently, a Classification Trees method was used to refine number of classes, describe the structure of reservoir watershed classes, and to develop a predictive model that relates watershed conditions to reservoir classes. Results suggest that Nebraska reservoirs can be represented by nine classes and that soil organic matter content in the watershed is the most important single variable for segregating the reservoirs. The cross‐validation prediction error rate of the Classification Tree model was 26.3%. Because all geospatial data used in this work are available nationally, the method could be adopted throughout the U.S. Hence, this GIS‐based watershed classification approach could provide water resources managers an effective decision‐support tool in managing reservoir water quality. 相似文献
993.
James Wilson 《Journal of Agricultural and Environmental Ethics》2007,20(3):261-283
This paper focuses on the ethical justifiability of patents on Genetically Modified (GM) crops. I argue that there are three
distinguishing features of GM crops that make it unethical to grant patents on GM crops, even if we assume that the patent
system is in general justified. The first half of the paper critiques David Resnik’s recent arguments in favor of patents
on GM crops. Resnik argues that we should take a consequentialist approach to the issue, and that the best way to do so is
to apply the Precautionary Principle, and that the Precautionary Principle, in this case, supports patents on GM crops. I
argue that his argument in favor of a consequentialist treatment is invalid; his Precautionary Principle in any case appears
to be incompatible with consequentialism; and his conception of reasonable precautions is too ill-defined to have any argumentative
purchase. In the second half of the paper, I argue against GM crop patents, on three grounds. First, there is insufficient
evidence to say whether allowing patents on GM crops will make research go faster than not having patents, whilst there is
a good reason to think that, other things being equal, a society that allows patents on GM crops will be less just than one
that does not. Second, even assuming that patents on GM crops will increase the pace of GM crop research, there is no social
need to do so. Third, patents on GM crops will frequently have ethically unacceptable side effects. 相似文献
994.
The traditional vision of the role science should play in policy making is of a two stage process of scientists first finding
out the facts, and then policy makers making a decision about what to do about them. We argue that this two stage process
is a fiction and that a distinction must be drawn between pure science and science in the service of public policy. When science
is transferred into the policy realm, its claims to truth get undermined because we must abandon the open-ended nature of
scientific inquiry. When we move from the sphere of science to the sphere of policy, we pick an arbitrary point in the open-ended
scientific process, and ask our experts to give us the answer. The choice of the endpoint, however, must always be arbitrary
and determined by non-scientific factors. Thus, the two stages in the model of first finding the facts, and then making a
decision about what to do, cannot be clearly separated. The second stage clearly affects the first. This conclusion will have
implications about existing scientific policy institutions. For example, we advocate that the environmental assessment process
be radically overhauled, or perhaps even let go. It will be our position that ultimately a better model for the involvement
of scientists in public policy debates is that of being participants in particular interest groups (“hired guns”), rather
than as supposedly unbiased consultants to decision-makers. 相似文献
995.
Hollamby S Afema-Azikuru J Waigo S Cameron K Gandolf AR Norris A Sikarskie JG 《Environmental monitoring and assessment》2006,118(1-3):13-20
An animal’s suitability as a biomonitor of environmental change can be determined by biological, reproductive and ecological
characteristics determined at the class, order and species level. The animal’s habitat where the research is to be performed
and the form, function and structure of the environmental change being studied within that habitat also determines suitability.
Non-threatened populations of large, non-migratory, long-lived, seasonally-breeding tertiary avian predators, whose dietary
preferences are narrow and known, can be useful as monitors of environmental chemical contaminants. If chemicals are being
monitored, a quantifiable endpoint effect must be demonstrated in the species, or a similar species under experimental laboratory
conditions. Logistical and economic issues as well as public and regulatory authority acceptance should also be considered
when assessing the suitability of a species as a biomonitor. 相似文献
996.
James P.Zeigler 《中国个体防护装备》2006,(2):37-41
本文作者Zeigler博士在防护服研究试验、防护服行业规定及标准、大规模杀伤性武器等方面具有专业知识。作者是美国材料与试验学会(ASTM)防护服F23委员会微粒物质分委员会主任,也是美国防火委员套紧急医疗服务和危险物质防护服厦装备技术委员会成员。为应对恐怖袭击,本文从美国政府拨款、协调机构、信息通报、危机分析、防护服装配备和储存、人员培训等方面进行了论述,有一定参考价值,现予发表,供有关部门、企业和广大读者参阅。 相似文献
997.
998.
999.
Modeling houses as two coupled chambers, namely, the living area and basement, predicts more accurately the total indoor radon source flux from building materials and geology than a one-chamber model in houses with disparate radon concentrations. Three regional surveys found mean radon concentration ratios between basement and living area to range from 1.4 to 4.2, implying weak interchamber coupling in most cases. The invariability of second-order system parameters under steady infiltration but different initial conditions confirms the adequacy of the two-chamber model. The presence of a characteristic radon source flux was detected within the basements of two houses, in one case across different infiltration, coupling, and initial conditions. One-chamber models fit to two-chamber tracer gas data in one house show a source flux variation of a factor of 6 across changing coupling, while the two-chamber source flux variation was only a factor of 1.5. A substantial fraction of the apparent one-chamber living area source flux in these cases is the variable convective radon flux from the basement. The technique is not sensitive enough to detect living area source fluxes if either the interchamber coupling is strong or if the basement source flux is substantially larger. 相似文献
1000.
Ken Inoue Makoto Kanai Yuzo Tanabe Takeo Kubota Catherine D. Kashork Keiko Wakui Yoshimitsu Fukushima James R. Lupski Lisa G. Shaffer 《黑龙江环境通报》2001,21(13):1133-1136
A submicroscopic genomic duplication in Xq22.2 that contains the entire proteolipid protein 1 gene (PLP1) is responsible for the majority of Pelizaeus–Merzbacher disease (PMD) patients. We previously developed an interphase FISH assay to screen for PLP1 duplications in PMD patients using peripheral blood and lymphoblastoid cell lines. This assay has been utilized as a clinical diagnostic test in our cytogenetics laboratory. To expand usage of the interphase FISH assay to prenatal diagnosis of PLP1 duplications, we examined three PMD families with PLP1 duplications utilizing aminiotic fluid samples. In two families the FISH assay revealed fetuses with PLP1 duplications, whereas the other fetus showed a normal copy number of PLP1. Haplotype analyses, as well as an additional FISH analysis using postnatal blood samples, confirmed the results of the prenatal analyses. Our study demonstrates utility of the interphase FISH assay in the prenatal diagnosis of PLP1 duplications in PMD. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献