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41.
Exposure to residues of the nonsteroidal anti‐inflammatory drug (NSAID) diclofenac present in livestock carcasses has caused extensive declines in 3 Gyps vulture species across Asia. The carcass of a wild Eurasian Griffon Vulture (Gyps fulvus) was found in 2012 on an Andalucian (Spain) game hunting reserve and examined forensically. The bird had severe visceral gout, a finding consistent with Gyps vultures from Asia that have been poisoned by diclofenac. Liver and kidney samples from this Eurasian Griffon Vulture contained elevated flunixin (an NSAID) levels (median = 2.70 and 6.50 mg/kg, respectively). This is the first reported case of a wild vulture being exposed to and apparently killed by an NSAID outside Asia. It is also the first reported instance of mortality in the wild resulting from environmental exposure to an NSAID other than diclofenac. Caso de Sospecha de Envenenamiento por Flunixin de un Buitre Leonado en España  相似文献   
42.
The bioconcentration factors (BCFs) of 2,3,7,8-TCDD in adipose tissue of rats, beef cattle and monkeys have been calculated. The bioconcentration potential of TCDD in man was calculated by two indirect methods: 1) from daily intake of TCDD and its measured concentrations in adipose tissues and 2) from measured half-life and measured concentrations in body fat at steady state using a linear one compartment pharmacokinetic model. The BCFs in humans calculated by both methods are between 104 and 206, or 153, respectively.  相似文献   
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44.
Crimson-breasted shrikes produce duets which are used in interactions with neighbours and intruders. We examined two major hypotheses explaining duetting, the territorial defence and mate guarding hypotheses, using playback experiments. The responses of 12 pairs towards solo male, solo female and stereo duet playback were analysed using principal component analysis and ANOVA. The measures of response intensity revealed in most cases highly coordinated responses of the pair partners. Although these joint responses could suggest cooperative territorial defence or mutual mate defence, responses to the treatments differed between males and females in terms of three variables. Females increased their answer rates significantly in response to unpaired female intruders, compared to unpaired male intruders. During duet playback, females directed their responses equally at both intruding pair members. In contrast, males were equally responsive towards unpaired male intruders and intruding pairs, but in the latter case directed their responses at the male pair member. In the presence of unpaired female intruders, males increased their solo song rates, but in the presence of intruding pairs, they increased overlapping rates and duetted with their mates. These divergent responses suggest that females use duets for mate guarding against unpaired females, whereas males use solo songs for mate guarding and both solos and duets in territorial defence.  相似文献   
45.
Drawing on self‐determination and self‐concept‐based theories, this study investigated the mediating effects of psychological empowerment and organization‐based self‐esteem on the relationship between supervisory mentoring and employee performance and the moderating effect of supervisor political skill on the direct and first stage of the indirect effects. Data were obtained from a sample of 330 subordinate–supervisor dyads from the People's Republic of China. Using PROCESS of conditional indirect effect, we found support for the moderated direct and indirect effects of supervisory mentoring. First, supervisor political skill moderates the direct effect of supervisory mentoring on employee promotability. Second, supervisor political skill moderates the indirect effect of supervisory mentoring on the following: (i) employee promotability via both psychological empowerment and organization‐based self‐esteem and (ii) contextual performance only via psychological empowerment. These direct and indirect effects of supervisory mentoring are stronger when supervisors demonstrate a higher level of political skill. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
46.
ABSTRACT

In recent work on commons and commoning, scholars have argued that we might delink the practice of commoning from property ownership, while paying attention to modes of governance that enable long-term commons to emerge and be sustained. Yet commoning can also occur as a temporary practice, in between and around other forms of use. In this article we reflect on the transitional commoning practices and projects enabled by the Christchurch post-earthquake organisation Life in Vacant Spaces, which emerged to connect and mediate between landowners of vacant inner city demolition sites and temporary creative or entrepreneurial users. While these commons are often framed as transitional or temporary, we argue they have ongoing reverberations changing how people and local government in Christchurch approach common use. Using the cases of the physical space of the Victoria Street site “The Commons” and the virtual space of the Life in Vacant Spaces website, we show how temporary commoning projects can create and sustain the conditions of possibility required for nurturing commoner subjectivities. Thus despite their impermanence, temporary commoning projects provide a useful counter to more dominant forms of urban development and planning premised on property ownership and “permanent” timeframes, in that just as the physical space of the city being opened to commoning possibilities, so too are the expectations and dispositions of the city’s inhabitants, planners, and developers.  相似文献   
47.
The Arctic experiences a high-radiation environment in the summer with 24-hour daylight for more than two months. Damage to plants and ecosystem metabolism can be muted by overcast conditions common in much of the Arctic. However, with climate change, extreme dry years and clearer skies could lead to the risk of increased photoxidation and photoinhibition in Arctic primary producers. Mosses, which often exceed the NPP of vascular plants in Arctic areas, are often understudied. As a result, the effect of specific environmental factors, including light, on these growth forms is poorly understood. Here, we investigated net ecosystem exchange (NEE) at the ecosystem scale, net Sphagnum CO2 exchange (NSE), and photoinhibition to better understand the impact of light on carbon exchange from a moss-dominated coastal tundra ecosystem during the summer season 2006. Sphagnum photosynthesis showed photoinhibition early in the season coupled with low ecosystem NEE. However, later in the season, Sphagnum maintained a significant CO2 uptake, probably for the development of subsurface moss layers protected from strong radiation. We suggest that the compact canopy structure of Sphagnum reduces light penetration to the subsurface layers of the moss mat and thereby protects the active photosynthetic tissues from damage. This stress avoidance mechanism allowed Sphagnum to constitute a significant percentage (up to 60%) of the ecosystem net daytime CO2 uptake at the end of the growing season despite the high levels of radiation experienced.  相似文献   
48.
To evaluate the effectiveness of emission control regulations designed for reducing air pollution, chemically resolved PM2.5 data have been collected across Canada through the National Air Pollution Surveillance network in the past decade. 24-hr time integrated PM2.5 collected at seven urban and two rural sites during 2010-2016 were analyzed to characterize geographical and seasonal patterns and associated potential causes. Site-specific seven-year mean gravimetric PM2.5 mass concentrations ranged from 5.7 to 9.6 µg/m3. Seven-year mean concentrations of SO42?, NO3?, NH4+, organic carbon (OC), and elemental carbon (EC) were in the range of 0.68 to 1.6, 0.21 to 1.5, 0.27 to 0.71, 1.1 to 1.9, and 0.37 to 0.71 µg /m3, accounting for 10.8%-18.1%, 3.7%-16.7%, 4.7%-7.4%, 18.4%-21.0%, and 6.4%-10.6%, respectively, of gravimetric PM2.5 mass. PM2.5 and its five major chemical components showed higher concentrations in southeastern Canada and lower values in Atlantic Canada, with the seven-year mean ratios between the two regions being on the order of 1.7 for PM2.5 and 1.8-7.1 for its chemical components. When comparing the concentrations between urban and rural sites within the same region, those of SO42? and NH4+ were comparable, while those of NO3?, OC, and EC were around 20%, 40%-50%, and 70%-80%, respectively, higher at urban than rural sites, indicating the regional scale impacts of SO42? and NH4+ and effects of local sources on OC and EC. Monthly variations generally showed summertime peaks for SO42? and wintertime peaks for NO3?, but those of NH4+, OC, and EC exhibited different seasonality at different locations.  相似文献   
49.
Environmental Science and Pollution Research - Phytoremediation represents a natural method to remove contaminants from soil. The goal of this study was to investigate the potential of...  相似文献   
50.
Effective EU and Member State policies for stimulating CCS   总被引:1,自引:0,他引:1  
Although CO2 capture and storage (CCS) is widely recognised as an option to mitigate climate change, consistent and effective EU policies to advance CCS are still absent. This paper discusses policy instruments for advancing large-scale deployment of CCS in the European Union, and evaluates them in a multi-criteria analysis. The EU Emissions Trading Scheme (EU-ETS) is a cost-effective instrument for limiting greenhouse gas emissions, but it is questionable whether its currently limited time horizon and short-trading periods will lead to substantial CCS diffusion. Complementary policies at the EU and the Member State level may repair this and provide sufficient incentives for CCS. Potential policies include financial instruments such as investment subsidies, a feed-in scheme, or a CO2 price guarantee, as well as a CCS mandate or a low-carbon portfolio. These policy options differ with respect to their environmental effectiveness, possible interaction with the EU-ETS, costs and financial risk involved, and their competition with other mitigation options. Interactions between Member State policies and the EU-ETS are smaller in scope than those of EU-wide policies, but they are more likely to lead to displacement of financial resources from other low-carbon technologies. In addition, national policies may pose a significant part of the financial risk of CCS operations with Member States, reducing the operator's incentive to innovate. Overall, structural policies at the EU level, such as a mandate or a low-carbon portfolio standard would be more conducive for realising large-scale deployment of CCS across the EU as well as more acceptable to environmental organisations.  相似文献   
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