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61.
62.
Walther Gerlach 《Die Naturwissenschaften》1941,29(42-43):656-656
63.
The present study examined the moderating role of reciprocation wariness in the association of employees' psychological contract fulfillment with psychosomatic strain and voluntary turnover, as mediated by perceived organizational support. To study these relationships longitudinally, 169 graduating college seniors were surveyed upon job acceptance and again 3 weeks, 3 months, 6 months, and 18 months following the start of employment. The findings showed that psychological contract fulfillment was positively related to perceived organizational support. However, this positive relationship was eliminated by reciprocation wariness, and this influence was carried over to psychosomatic strain and voluntary turnover. Thus, it appears that reciprocation wariness leads employees to discount psychological contract fulfillment as an indication of the organization's valuation and caring. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Justin D. K. Bishop Gehan A. J. Amaratunga Cuauhtemoc Rodriguez 《Environment, Development and Sustainability》2010,12(2):213-231
Anthropogenic climate and land-use change are leading to irreversible losses of global biodiversity, upon which ecosystem
functioning depends. Since total species' well-being depends on ecosystem goods and services, man must determine how much
net primary productivity (NPP) may be appropriated and carbon emitted so as to not adversely impact this and future generations.
In 2005, man ought to have only appropriated 9.72 Pg C of NPP, representing a factor 2.50, or 59.93%, reduction in human-appropriated
NPP in that year. Concurrently, the carbon cycle would have been balanced with a factor 1.26, or 20.84%, reduction from 7.60
Gt C/year to 5.70 Gt C/year, representing a return to the 1986 levels. This limit is in keeping with the category III stabilization
scenario of the Intergovernmental Panel for Climate Change. Projecting population growth to 2030 and its associated basic
food requirements, the maximum HANPP remains at 9.74 ± 0.02 Pg C/year. This time-invariant HANPP may only provide for the
current global population of 6.51 billion equitably at the current average consumption of 1.49 t C per capita, calling into
question the sustainability of developing countries striving for high-consuming country levels of 5.85 t C per capita and
its impacts on equitable resource distribution. 相似文献
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The John Heinz National Wildlife Refuge is subject to pollution from multiple sources. We studied development of snapping turtle (Chelydra serpentina) and painted turtle (Chrysemys picta) embryos from the refuge from 2000 through 2003. Mean annual deformity rate of pooled painted turtle clutches over four years ranged from 45 to 71%, while that of snapping turtle clutches ranged from 13 to 19%. Lethal deformities were more common than minor or moderate deformities in embryos of both species. Adult painted turtles had a higher deformity rate than adult snapping turtles. Snapping turtles at JHNWR had high levels of PAH contamination in their fat. This suggests that PAHs are involved in the high level of deformities. Other contaminants may also play a role. Although the refuge offers many advantages to resident turtle populations, pollution appears to place a developmental burden on the life history of these turtles. 相似文献
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To effectively use a passive sampler for monitoring trace contaminants in the gas-phase, its sampling characteristics as a function of ambient wind conditions must be known. In this study two commonly used passive samplers were evaluated using computational fluid dynamics. Contaminant uptake by the polyurethane foam (PUF) was modeled using a species transport model. The external-internal flow interactions in the sampler were characterized, and the uptake rates of contaminant species were quantified. The simulations show that flow fields in the samplers have strong velocity gradients, and single-point velocity measurements do not capture flow interactions accurately. Sampling rates calculated for a PUF in freestream are in good agreement with sampling rates for PUFs in the passive samplers studied for the same average velocity over the PUF. The calculated sampling rates are in general agreement with those obtained experimentally by other researchers. 相似文献
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Advanced paternal age (APA) is associated with infertility and other reproductive risks. Studies looking at APA and outcomes have used different paternal age cut-offs, which has complicated systematic evaluations of reproductive risk associated with paternal aging. This review of the literature suggests that the impact of paternal aging on adverse reproductive outcomes is small, but significant. Studies suggest the incidence of paternal age effect disorders attributed to de novo autosomal dominant mutations is less than 0.5%. Other risks associated with APA include infertility, miscarriage, birth defects, poor neurodevelopmental outcomes, and childhood cancer. Although the increasing prevalence of APA has mirrored the rise in maternal age, this topic has not received similar attention. In this review, we summarize the available literature on the reproductive risks associated with APA to provide a framework for comprehensive genetic counseling and evidence-based management of APA pregnancies. 相似文献