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181.
In this study, we investigate, through two study samples, whether relationships between social leader–member exchange (SLMX) and economic leader–member exchange (ELMX) relationships and outcomes differ depending on the followers' level of other orientation or the extent to which they are concerned for the welfare of others. We propose that followers with higher other orientation would respond less negatively to higher levels of ELMX and more positively to higher levels of SLMX because they are less likely to engage in behaviors based on rational and self‐interested calculations. In Study 1 (N = 200), we found that higher other orientation mitigated ELMX's negative relations with affective commitment and turnover intention. In Study 2 (N = 4,518), we both replicated the findings from Study 1 and also found that higher other orientation mitigated ELMX's negative relations with work effort. We also uncovered a weaker positive relationship between SLMX and organizational citizenship behavior for followers with higher other orientation.  相似文献   
182.
Objectives: The objective of this article is to assess the status of road safety in Asia and present accident and injury prevention strategies based on global road safety improvement experiences and discuss the way forward by indicating opportunities and countermeasures that could be implemented to achieve a new level of safety in Asia.

Methods: This study provides a review and analyses of data in the literature, including from the World Health Organization (WHO) and World Bank, and a review of lessons learned from best practices in high-income countries. In addition, an estimation of costs due to road transport injuries in Asia and review of future trends in road transport is provided.

Results: Data on the global and Asian road safety problem and status of prevention strategies in Asia as well as recommendations for future actions are discussed. The total number of deaths due to road accidents in the 24 Asian countries, encompassing 56% of the total world population, is 750,000 per year (statistics 2010). The total number of injuries is more than 50 million, of which 12% are hospital admissions. The loss to the economy in the 24 Asian countries is estimated to around US$800 billion or 3.6% of the gross domestic product (GDP).

Conclusions: This article clearly shows that road safety is causing large problems and high costs in Asia, with an enormous impact on the well-being of people, economy, and productivity. In many Asian low- and middle-income countries, the yearly number of fatalities and injuries is increasing. Vulnerable road users (pedestrians, cyclists, and motorcyclists combined) are particularly at risk. Road safety in Asia should be given rightful attention, including taking powerful, effective actions. This review stresses the need for reliable accident data, because there is considerable underreporting in the official statistics. Reliable accident data are imperative to determine evidence-based intervention strategies and monitor the success of these interventions and analyses. On the other hand, lack of good high-quality accident data should not be an excuse to postpone interventions. There are many opportunities for evidence-based transport safety improvements, including measures concerning the 5 key risk factors: speed, drunk driving, not wearing motorcycle helmets, not wearing seat belts, and not using child restraints in cars, as specified in the Decade of Action for Road Safety 2011–2020. In this commentary, a number of additional measures are proposed that are not covered in the Decade of Action Plan. These new measures include separate roads or lanes for pedestrians and cyclists; helmet wearing for e-bike riders; special attention to elderly persons in public transportation; introduction of emerging collision avoidance technologies, in particular automatic emergency braking (AEB) and alcohol locks; improved truck safety focusing on the other road user (including blind spot detection technology; underride protection at the front, rear, and side; and energy-absorbing fronts); and improvements in motorcycle safety concerning protective clothing, requirements for advanced braking systems, improved visibility of motorcycles by using daytime running lights, and better guardrails.  相似文献   

183.
The aim of this study was to provide policy-makers and waste management planners with information about how recycling programs affect the quantities of specific materials recycled and disposed of. Two questions were addressed: which factors influence household waste generation and pathways? and how reliable are official waste data? Household waste flows were studied in 35 Swedish municipalities, and a wide variation in the amount of waste per capita was observed. When evaluating the effect of different waste collection policies, it was found to be important to identify site-specific factors influencing waste generation. Eleven municipal variables were investigated in an attempt to explain the variation. The amount of household waste per resident was higher in populous municipalities and when net commuting was positive. Property-close collection of dry recyclables led to increased delivery of sorted metal, plastic and paper packaging. No difference was seen in the amount of separated recyclables per capita when weight-based billing for the collection of residual waste was applied, but the amount of residual waste was lower. Sixteen sources of error in official waste statistics were identified and the results of the study emphasize the importance of reliable waste generation and composition data to underpin waste management policies.  相似文献   
184.
We compared root responses of the Ni-hyperaccumulator plant Berkheya coddii Rossler with the non-accumulator plant Cicer arietinum L. to Ni heterogeneity in soil. We grew plants in growth containers filled with control soil, homogeneously spiked, and heterogeneously spiked soil with Ni concentrations of 62 and 125 mg kg?1. Neutron radiography (NR) was used to observe the root distribution and the obtained images were analysed to reveal the root volumes in the spiked and unspiked segments of the growth container. There was no significant difference in root distribution pattern of B. coddii among different concentrations of Ni. Unlike B. coddii, the roots of C. arietinum initially grew into the spiked segments. However, the later developing roots did not penetrate the spiked segment suggesting an avoidance strategy. Our results indicate that, B. coddii does not forage towards the Ni-rich patches, although presence of Ni in soil changes its root morphology.  相似文献   
185.
The shredder residues from automobiles, home appliances and other metal containing products are often disposed in landfills, as recycling technologies for these materials are not common in many countries. Shredder waste contains rigid and soft foams from cushions and insulation panels blown with fluorocarbons. The objective of this study was to determine the gas composition, attenuation, and emission of fluorocarbons in a monofill shredder residue landfill cell by field investigation. Landfill gas generated within the shredder waste primarily consisted of CH4 (27%) and N2 (71%), without CO2, indicating that the gas composition was governed by chemical reactions in combination with anaerobic microbial reactions. The gas generated also contained different fluorocarbons (up to 27 μg L?1). The presence of HCFC-21 and HCFC-31 indicated that anaerobic degradation of CFC-11 occurred in the landfill cell, as neither of these compounds has been produced for industrial applications. This study demonstrates that a landfill cell containing shredder waste has a potential for attenuating CFC-11 released from polyurethane (PUR) insulation foam in the cell via aerobic and anaerobic biodegradation processes. In deeper, anaerobic zones of the cell, reductive dechlorination of CFCs to HCFCs was evident, while in the shallow, oxic zones, there was a high potential for biooxidation of both methane and lesser chlorinated fluorocarbons. These findings correlated well with both laboratory results (presented in a companion paper) and surface emission measurements that, with the exception from a few hot spots, indicated that surface emissions were negative or below detection.  相似文献   
186.
The Steady State Water Chemistry Model (SSWCM) is a common method for determinations of critical loadof acid and subsequently of critical loadexceedance for lakes. One way to verify the modeloutput, is to compare with chemical indicatorssuch as pH-value, alkalinity or ANC. When themedian chemical status (as ANC) is used 65% ofthe lakes responded according to the exceedancevalue. For these the calculated exceedanceresulted in violation of the critical chemicalvalue while non-exceedance gave no violation.Since biota react on extreme conditions a morecorrect evaluation should be based on minimumvalues for the chemical indicator. This raises thefraction of lakes responding to 78%. Non-exceedance is seldom found inlakes with acid conditions. The evaluationindicates that the calculation of critical load ofacidity by means of SSWCM is very reliable.  相似文献   
187.
Wild game and other renewable resources in tropical rainforests inhabited by indigenous peoples are currently often exploited in unsustainable ways. This article shows, for a Kichwa community in the Ecuadorian Amazon, that this can to some extent be explained as a 'tragedy of the commons'. However there are also other mechanisms at work. In particular, there has been some unawareness of the impact of hunting on game populations, and the expansion of fallows at the expense of old growth forest is a result of population growth that increases the need for farmland, and thus decreases the socially optimal area of old growth forest. Whereas many resources are harvested under conditions resembling open access, there have long been established rules for the harvest of thatch leaves, and the community has recently also adopted several measures in order to regulate hunting. Obviously, experiences of resource scarcity may spark conservationist thinking and behaviour. This is a process that scientists can and should support.  相似文献   
188.
The shredder residues from automobiles, home appliances and other metal-containing products are often disposed in landfills, as recycling technologies for these materials are not common in many countries. Shredder waste contains rigid and soft foams from cushions and insulation panels blown with fluorocarbons. The objective of this study was to use laboratory experiments to estimate fluorocarbon release and attenuation processes in a monofill shredder residue (SR) landfill cell. Waste from the open SR landfill cell at the AV Miljø landfill in Denmark was sampled at three locations. The waste contained 1–3% metal and a relatively low fraction of rigid polyurethane (PUR) foam particles. The PUR waste contained less blowing agent (CFC-11) than predicted from a release model. However, CFC-11 was steadily released in an aerobic bench scale experiment. Anaerobic waste incubation bench tests showed that SRSR produced significant methane (CH4), but at rates that were in the low end of the range observed for municipal solid waste. Aerobic and anaerobic batch experiments showed that processes in SRSR potentially can attenuate the fluorocarbons released from the SRSR itself: CFC-11 is degraded under anaerobic conditions with the formation of degradation products, which are being degraded under CH4 oxidation conditions prevailing in the upper layers of the SR.  相似文献   
189.
The process of solidification with water was studied on air pollution control (APC) residues from incineration of refuse-derived fuel (RDF) regarding mechanical strength and leaching behaviour of solidified material. Factorial design in two levels was applied to investigate the impact of water addition, time, and temperature to mechanical strength of solidified material. Factors time and temperature, as well as the interaction between the addition of water and time significantly (alpha=0.05) influenced the mechanical strength of solidified material. The diffusion-leaching test NEN 7345 was performed to investigate if the leaching behaviour of elements from solidified material was determined by diffusion. Since it was found that leaching is not diffusion controlled, the long-term leaching behaviour was not assessed. However, the investigation showed that some of the studied components (Al, Hg, Mn, Pb, Si, and Zn) could be considerably demobilised by solidification with water. Concentrations of As, Cd, Co, Cu, Fe, and Ni were either below or not quite above the detection limits to be included in the analysis of leaching behaviour. The elements least demobilised by solidification were Cl, Cr, K, and Na.  相似文献   
190.
To provide information necessary for a license application for a deep repository for spent nuclear fuel, the Swedish Nuclear Fuel and Waste Management Co is carrying out site investigations, including extensive studies of different parts of the surface ecosystems, at two sites in Sweden. Here we use the output from detailed modeling of the carbon dynamics in the terrestrial, limnic and marine ecosystems to describe and compare major pools and fluxes of organic matter in the Simpevarp area, situated on the southeast coast of Sweden. In this study, organic carbon is used as a proxy for radionuclides incorporated into organic matter. The results show that the largest incorporation of carbon into living tissue occurs in terrestrial catchments. Carbon is accumulated in soil or sediments in all ecosystems, but the carbon pool reaches the highest values in shallow near-land marine basins. The marine basins, especially the outer basins, are dominated by large horizontal water fluxes that transport carbon and any associated contaminants into the Baltic Sea. The results suggest that the near-land shallow marine basins have to be regarded as focal points for accumulation of radionuclides in the Simpevarp area, as they receive a comparatively large amount of carbon as discharge from terrestrial catchments, having a high NPP and a high detrital accumulation in sediments. These focal points may constitute a potential risk for exposure to humans in a future landscape as, due to post-glacial land uplift, previous accumulation bottoms are likely to be used for future agricultural purposes.  相似文献   
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