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31.
We empirically reveal how environmental experts interpret the objectivity norm while navigating the authority paradox. The paradox here is that while there is a need for objective scientific advice, such advice is only to be acquired from experts and expert agencies whose objectivity and, hence, authority are contested. Viewed through the lens of practice, we identify what practitioners at the PBL Netherlands Environmental Assessment Agency understand by objectivity. Using this paradigmatic case, we show how practitioners renegotiate the meaning of objectivity while seeking to engage with new policy actors and extended peers in an independent, rigorous and legitimate manner. Successfully navigating the authority paradox is related to skilfully representing and adapting to various meanings of objectivity. Experts and experts agencies accordingly need reflexive skills to recognise which meanings of objectivity they ascribe to and which ones are invoked in public debates. Environmental experts who are able to loosely connect diverse objectivity conceptions are more likely considered as trustworthy and authoritative partners in environmental science-policy interfaces. 相似文献
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In a transition to a bio-based economy new ways of monitoring waste-streams and water quality can then contribute to sustainable production processes. As niche innovation, new ways of monitoring face systemic barriers. The present article examines how barriers to change manifest in discursive practices with differing normative attachments and implications. A frame analysis revealed two competing frames: (1) the dominant ‘norm water’ frame in which thresholds of chemical compounds are used to set policy targets; and (2) the contesting ‘living water’ frame, which entails innovative continuous monitoring tools that take into account the ecological effects of chemical compounds. We introduce the concept of interactive reflectivity, as a discursive tool, to collaboratively visualize, scrutinize and overcome discursive barriers to innovations. The stakeholder dialogue shows how systemic barriers are uttered discursively in niches – or other forms of responsible research and innovation – and may hinder change even at the niche-level. 相似文献
33.
We adopt an interpersonal perspective and examine the adaptive effects of managers' perceived stress on their behavior towards subordinates. Drawing from the transactional model of stress (Lazarus & Folkman, 1984), we advance a model that highlights the propensity for stressed managers to engage in prosocial coping behaviors towards their employees, which in turn are related to lower levels of turnover and higher levels of job performance. We tested our predictions in a sample of 281 employees and their 53 managers working in a clothing retailer in Turkey. Consistent with predictions, we found positive effects of managers' perceived stress on their prosocial coping behaviors and employee outcomes. Managers' perceived stress was positively related to sharing credit with employees for managers who held positive implicit prototypes about employees. Results also indicated that managers' perceived stress was positively related to sharing knowledge with their subordinates regardless of implicit follower prototypes. Both sharing credit and sharing knowledge, in turn, were related to turnover intentions and actual turnover, and sharing credit was related to job performance. This study extends past work by adopting an interpersonal perspective of stress and demonstrating that managerial stress can have positive effects on employee outcomes via prosocial coping behaviors. 相似文献
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The presence of an immobile gaseous phase in an otherwise-saturated porous medium affects the transport of volatile compounds. The linear theory of partitioning tracers suggests that a volatile tracer introduced into such a system should be retarded with a constant retardation factor. Using high concentrations, however, the saturation of the gaseous phase will change as an effect of the tracer test itself. Competitive gas transfer among all volatile compounds and the change of saturation may lead to tracer concentrations that are temporarily higher than those injected. We analyze the system in the framework of the coherence theory by Helfferich [Soc. Pet. Eng. J. 21 (1) (1981) 51]. The governing equations are formulated as functions of total concentration, i.e., the mass of solutes in all phases per pore volume. Neglecting dispersion and mass-transfer kinetics, we derive the characteristic form of the resulting system of hyperbolic equations. In a system with N volatile compounds, a variation of the concentrations splits up into N waves, each traveling with its own characteristic velocity. If the presence of a gaseous phase is sustained, one wave will be a standing one. We perform numerical model calculations for tracers with various Henry's law coefficients and show that the results agree with the semi-analytical solution obtained by coherence theory. 相似文献
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Decisions in ecological risk management for chemical substances must be made based on incomplete information due to uncertainties. To protect the ecosystems from the adverse effect of chemicals, a precautionary approach is often taken. The precautionary approach, which is based on conservative assumptions about the risks of chemical substances, can be applied selecting management models and data. This approach can lead to an adequate margin of safety for ecosystems by reducing exposure to harmful substances, either by reducing the use of target chemicals or putting in place strict water quality criteria. However, the reduction of chemical use or effluent concentrations typically entails a financial burden. The cost effectiveness of the precautionary approach may be small. Hence, we need to develop a formulaic methodology in chemical risk management that can sufficiently protect ecosystems in a cost-effective way, even when we do not have sufficient information for chemical management. Information-gap decision theory can provide the formulaic methodology. Information-gap decision theory determines which action is the most robust to uncertainty by guaranteeing an acceptable outcome under the largest degree of uncertainty without requiring information about the extent of parameter uncertainty at the outset. In this paper, we illustrate the application of information-gap decision theory to derive a framework for setting effluent limits of pollutants for point sources under uncertainty. Our application incorporates a cost for reduction in pollutant emission and a cost to wildlife species affected by the pollutant. Our framework enables us to settle upon actions to deal with severe uncertainty in ecological risk management of chemicals. 相似文献
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Is the integration of hormesis and essentiality into ecotoxicology now opening Pandora's Box? 总被引:1,自引:1,他引:1
Kefford BJ Zalizniak L Warne MS Nugegoda D 《Environmental pollution (Barking, Essex : 1987)》2008,151(3):516-523
Hormesis and essentiality are likely real and common effects at the level of the individual. However, the widespread incorporation of stimulatory effects into applications of ecotoxicology requires the acceptance of assumptions, value judgements and possibly lowering of water/sediment quality standards. There is also currently little data appropriate for considering hormetic effects in the ecotoxicological context. Except perhaps in the case of fitting concentration-response curves, it is not clear that incorporation of hormetic and essentiality type responses into ecotoxicology is necessary. Furthermore, its incorporation presents considerable intellectual and practical changes for ecotoxicology and could have unanticipated consequences. 相似文献
39.
The undermining effect revisited: The salience of everyday verbal rewards and self‐determined motivation 下载免费PDF全文
Self‐determination theory suggests that some rewards can undermine autonomous motivation and related positive outcomes. Key to this undermining is the extent to which rewards are perceived as salient in a given situation; when this is the case, individuals tend to attribute their behavior to the incentive, and the intrinsic value of the task is undermined. The role of salience has yet to be explicitly tested with respect to work motivation; we know little about whether undermining occurs in relation to verbal rewards, which characterize everyday work. We examine this in a field‐based quantitative diary study of 58 employees reporting 287 critical incidents of motivated behavior. When considering simple direct effects, the undermining effect was not supported; highly salient verbal rewards associated positively with introjected and external motivation, but at no cost to autonomous motivation. However, moderator analysis found support for the undermining effect for complex tasks; highly salient verbal rewards associated positively with external motivation while associating negatively with intrinsic and identified motivation. The findings suggest that verbal reward salience is an important characteristic of verbal reward perceptions and that salient verbal rewards are not advisable for more complex tasks but can have a valuable motivational impact for simple tasks. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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