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141.
《组织行为杂志》2017,38(6):876-894
Exploring the role of both the employee and supervisor, we tested a model of how cognition‐based work‐to‐family conflict manifests itself in the workplace, impacting employee job success. Based on conservation of resources theory and the concept of loss spirals, we hypothesized that when an employee's work interferes with family demands, the resulting work‐to‐family conflict spills over to the work domain via employee emotional exhaustion. We further argued that the behavioral manifestation of employee emotional exhaustion in the workplace is low employee engagement, as assessed by the supervisor. Drawing on signaling theory, we proposed that supervisor assessments of employee engagement are related to promotability, performance ratings, and salary. Work scheduling autonomy, as a boundary condition, is examined as a resource that attenuates these relationships. Data collected from 192 employee–supervisor dyads of a Fortune 1000 company, as well as performance ratings and salary obtained from company records 9 months later, indicated support for our conceptual model. Future research examining employee work–family conflict and job outcomes is discussed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
142.
One of the key determinants of success in biodiversity conservation is how well conservation planning decisions account for the social system in which actions are to be implemented. Understanding elements of how the social and ecological systems interact can help identify opportunities for implementation. Utilizing data from a large‐scale conservation initiative in southwestern of Australia, we explored how a social–ecological system framework can be applied to identify how social and ecological factors interact to influence the opportunities for conservation. Using data from semistructured interviews, an online survey, and publicly available data, we developed a conceptual model of the social–ecological system associated with the conservation of the Fitz‐Stirling region. We used this model to identify the relevant variables (remnants of vegetation, stakeholder presence, collaboration between stakeholders, and their scale of management) that affect the implementation of conservation actions in the region. We combined measures for these variables to ascertain how areas associated with different levels of ecological importance coincided with areas associated with different levels of stakeholder presence, stakeholder collaboration, and scales of management. We identified areas that could benefit from different implementation strategies, from those suitable for immediate conservation action to areas requiring implementation over the long term to increase on‐the‐ground capacity and identify mechanisms to incentivize implementation. The application of a social–ecological framework can help conservation planners and practitioners facilitate the integration of ecological and social data to inform the translation of priorities for action into implementation strategies that account for the complexities of conservation problems in a focused way. 相似文献
143.
James N. Carleton Yusuf M. Mohamoud 《Journal of the American Water Resources Association》2013,49(1):205-216
Carleton, James N. and Yusuf M. Mohamoud, 2012. Effect of Flow Depth and Velocity on Nitrate Loss Rates in Natural Channels. Journal of the American Water Resources Association (JAWRA) 1‐12. DOI: 10.1111/jawr.12007 Abstract: Loss rates of nitrate from streams and rivers are governed by movement of the ion from water column to anoxic bed sediments. Quantitative representations of nitrate in streams and rivers have often treated such losses as governed by first‐order mechanisms that are invariant with respect to potential modulating factors other than temperature. Results of studies in recent years, however, suggest that rates of water column‐sediment mass transfer are influenced by stream geometry and associated hydraulics. We develop expressions for the instream nitrate loss rate coefficient, k, as a function of water velocity and depth, using hydraulic geometry to empirically relate velocity to depth for two cases: (1) variability in mean conditions among reaches; and (2) temporal variability in conditions at a single reach, under changing flow. The result is expressions for k as functions of water column depth. Measured stream k values reported in the literature are shown to be well represented by expressions developed for the first case, and the potential for application to probabilistic analysis is briefly examined. We explore the latter case using the Hydrologic Simulation Program – FORTRAN (HSPF) model, modified to incorporate the dependence of k on instantaneous stream depth. In example simulations of two nitrate‐exporting watersheds, the incorporation of depth‐dependence of k produces improvement in the model’s ability to match observed stream nitrate concentrations. 相似文献
144.
Martin J. Steinbauer Fredrik Östrand Tom E. Bellas Anna Nilson Fredrik Andersson Erik Hedenström Michael J. Lacey P. Florian Schiestl 《Chemoecology》2004,14(3-4):217-223
Summary. The autumn gum moth, Mnesampela privata
(Guenée) (Lepidoptera: Geometridae), is native to Australia
and can be a pest of plantation eucalypts. Field-collected
and laboratory-reared female autumn gum moths were
dissected to remove glands likely to contain components of
the sex pheromone. Using gas chromatography (GC) and
combined gas chromatography–mass spectrometry (GC-MS),
three compounds were identified from female extracts,
namely (3Z,6
Z,9
Z)-3,6,9-nonadecatriene, 1-hexadecanol
and 1-octadecanol (confirmed by comparison with synthetic
samples). Nonadecatriene elicited an antennal response in
male autumn gum moth during gas chromatographic
analyses combined with electroantennographic detection
(GC-EAD). In electroantennogram (EAG) recording male
M. privata antennae responded to the nonadecatriene. Nonadecatriene was synthesised via Kolbe electrolysis,
starting with (9Z,12Z,15Z)-octadeca-9,12,15-trienoic acid
(linolenic acid) and propanoic acid or via an alternative
four-step method also starting from linolenic acid. In field
trials (3Z,6Z,9Z)-3,6,9-nonadecatriene proved attractive
to male moths. Thus, we conclude that (3Z,6Z,9Z)-3,6,9-
nonadecatriene is a sex pheromone component of autumn
gum moth. This component has been identified in extracts
from other geometrids in the same subfamily, Ennominae.
However, to our knowledge this is the first example where
(3Z,6Z,9Z)-3,6,9-nonadecatriene has been found in females
and also proved attractive to male moths when presented on its
own. Our results are discussed in relation to other geometrid
pheromones. 相似文献
145.
146.
A.M.G. de Bruijn K. Butterbach-Bahl S. Blagodatsky R. Grote 《Agriculture, ecosystems & environment》2009,133(3-4):196
N2O emissions from soil contribute significantly to global warming. Pulse emissions of N2O from soils during freeze-thawing were recently recognized as important atmospheric sources. In this modelling study we explore three different hypotheses for explaining freeze–thaw related N2O emissions: (1) soil frost or snow cover may reduce gas diffusion and create anaerobic conditions that stimulate N2O production via denitrification, (2) microbes that die of frost deliver easy decomposable organic carbon and nitrogen to the soil, which stimulates microbial growth and vigorous N2O production during freeze–thaw, and (3) the enzyme nitrous oxide reductase, which is responsible for the reduction of N2O to N2 during denitrification, is more sensitive to low temperatures than other enzymes, so that N2O becomes the dominating end-product of denitrification at low temperatures. These hypotheses were tested with a biogeochemical model that combines hydrology and physics calculations with a newly developed, parameter-poor biochemistry module. The model was first calibrated with field datasets on soil–atmosphere fluxes of N2O, NO and CO2 and soil NO3 and NH4 concentrations that were measured in a spruce forest in Southeast Germany in the years 1994–1997. Subsequently, additional model mechanisms were implemented that allow the model to describe the outlined mechanisms potentially driving freeze–thaw N2O fluxes. After each implementation the model was recalibrated. We were able to mimic dimension and timing of high N2O emissions when either one of the first two hypotheses were assumed, but found no confirmation for the third. The best model fit was achieved by combining hypothesis one and two, indicating that freeze–thaw N2O emissions are not mono-causal. 相似文献
147.
Silvia Danielak 《Disasters》2022,46(1):271-295
This paper spotlights post-disaster relief provision in Johannesburg, South Africa, following the floods of 2016 in a bid to explore how local government and non-governmental actors in the country conceive of compounding vulnerability and conflict within urban disaster governance. It reveals the diverse strategies employed to navigate violent conflict during the cyclical occurrence of disaster and reconstruction that the predominantly migrant population experiences in the Setswetla informal settlement, adjacent to the Alexandra township in northern Johannesburg. Rendered visible in moments of disaster and recovery are the spatial politics and multidimensional nature of conflict. These phenomena unfold across various levels of urban governance and in the affected community and effectively construct a disaster citizenship that makes risk reduction and community cohesion impossible in the eyes of disaster managers. This research, based on a set of expert interviews, integrates conflict and disaster studies to shed light on how the conflict–disaster interface materialises, and is operationalised, in an urban setting. 相似文献
148.
Using a large national sample based on Workplace and Employee Survey data collected by Statistics Canada in 2001 and 2002, we examined the effects of employee usage of seven organizational work–life interface benefits on promotions. Analysis predicted promotions in 2002 when number of promotions received by 2001 were controlled. The main effect of using work–life interface benefits on promotions was positive, indicating that using these benefits is not a career‐limiting move. Gender, presence of young children, and marital status interacted with the use of work–life interface benefits. Single parents benefitted less than other employees from using work–life interface options. Altogether, these findings suggest that the ongoing positive effects of conservation of time and energy resources for employees outweigh the initial short‐term negative effects of signaling and stigmatization. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
149.
Although the prevalence of employees working within the same workplace or occupation with their spouse has increased, relatively little research has examined their experiences. On the basis of the boundary and conservation of resources (COR) theories, we argue that higher levels of work–family role integration among work‐linked couples will lead to higher levels of spousal support resources and lower levels of work–family conflict. This will, in turn, lead to lower emotional exhaustion among employees in a work‐linked relationship. Among two samples of employees in a variety of occupations, we found that being in a work‐linked relationship was associated with both higher spousal instrumental support as well as different forms of work–family conflict. The interaction between spousal support and work–family conflict was associated with emotional exhaustion. We discuss the implications of these findings for boundary and COR theories in terms of movement of resources across work–family boundaries and resource relevance in the strain process. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
150.
A dynamic simulation model was constructed using outputs from a balanced Gulf of Maine (GOM) energy budget model as the initial parameter set. The model was structured to provide a recipient control set of dynamics, largely based off of flows to and from different biological groups. The model was used to produce Monte Carlo simulations that were compared (percent change in biomass) with basecase simulations for a variety of scenarios. Changes in primary production, large increases in pelagic and demersal fish biomass, increases in fishing mortality, and large increases in top predators such as baleen whales and pinnepids were simulated. These scenarios roughly simulated the potential impacts of climate change, altered fishing pressure, additional protected species mitigations, and combinations thereof. Results suggest that the GOM system is primarily influenced by bottom-up processes involving phytoplankton, zooplankton, and bacterial biomass. Pelagic and demersal fish were important in determining trends in some of the scenarios. Marine mammals, large pelagic fish, and seabirds have a minor role in the GOM system in terms of biomass flows among the ecosystem components. The system is resilient to large-scale change due, in part to many predator–prey linkages. However, major alterations could occur from sustained climate change, high fishing rates, and by combinations of these types of external forcing mechanisms. 相似文献