Employee voice behavior: A meta‐analytic test of the conservation of resources framework

Although voice (i.e. expressing change‐oriented ideas and suggestions) has frequently been investigated as a way for workers to reciprocate to their employers for the positive treatment they receive, much less is known about how workers use voice to deal with stress. This study takes a conservation of resources perspective to examine the relationships among workplace stress, voice behavior, and job performance. We first examined the strength of relationships of three major groups of workplace stressors and strains (job based, social based, and organization based) with voice behavior. We then examined the relationships of voice behavior with performance variables (e.g. in‐role performance and creativity) to investigate how voice may help workers preserve or accumulate resources to enhance their performance. The meta‐analytic findings presented here provide support for a negative relationship between workplace stress and voice and a positive relationship between voice behavior and performance outcomes. Copyright © 2011 John Wiley & Sons, Ltd.     

Risky driving and the perception of motorcycle accident causes among chinese motorcyclists in Hong Kong

Objective: The primary purposes of this study were to explore the relationship between risk-taking acts while driving motorcycles and perceived causes of motorcycle accidents, as well as their contribution to active involvement in traffic accidents among Chinese motorcyclists in Hong Kong. Active involvement means the riders was likely at fault for the crash. Methods: A total of 774 motorcyclists were recruited, of whom 292 had been involved in active motorcycle accident in the previous 3?years. All were asked to fill in a questionnaire, which was developed to assess their risk-taking acts while driving a motorcycle and perception of motorcycle accident causes. Results: The results of the study revealed 3 dimensions of accident causes, namely, driving-related, environment-related, and belief-related causes. These motorcycle accident causes were correlated with risk-taking acts while driving a motorcycle. A multivariate logistic regression analysis showed that risk-taking acts while driving motorcycles (adjusted odds ratio [OR]: 1.036, 95% confidence interval [CI]: 1.020-1.052), perception of driving-related cause (adjusted OR: 0.941, 95% CI: 0.916-0.967), and belief-related cause (adjusted OR: 1.134, 95% CI: 1.088-1.182) were significant factors contributing to involvement in active traffic accidents by motorcycle riders after controlling for concurrent demographic variables. Conclusions: The study highlights that perceived causes of motorcycle accidents are multidimensional, including those areas related to driving, the environment, and beliefs. It substantiates previous studies that a higher degree of driving-related risk perception is related to a lower degree of risk-taking acts while driving. Further research is needed to understand why belief-related causes, sometimes called superstitions, lead riders to believe that it is beyond their ability to affect accident causation and prevention.     

Assessment of soil washing for heavy metal contaminated paddy soil using FeCl3 washing solutions

Environmental Geochemistry and Health - In this study, soil washing is applied for the remediation of heavy-metal (Pb, Cu and Zn) contaminated paddy soil located near an abandoned mine area. FeCl3...     

Functional values of stabilimenta in a wasp spider, Argiope bruennichi: support for the prey-attraction hypothesis

Many orb-weaving spiders decorate their webs with conspicuous ultraviolet (UV)-reflective stabilimenta. The prey-attraction hypothesis suggests that stabilimenta are visually attractive to prey and thus may increase the spiders’ foraging success. However, previous studies on the function of stabilimenta have produced conflicting results in Argiope species. Using a combination of field and laboratory studies, we examined whether the linear stabilimentum of Argiope bruennichi contributes to prey interception. We recorded prey interceptions in 53 webs with stabilimenta and 37 equally-sized webs without stabilimenta, classifying captured prey according to their taxonomical group and size. On average, 6.2?±?4.7 prey items were intercepted in webs with stabilimenta, while 3.2?±?2.9 items were intercepted in webs without stabilimenta. The effects of stabilimenta on foraging success appear to be due to increased interception of UV-sensitive insect pollinators, including 20 families of Diptera, Hymenoptera, Coleoptera, and Lepidoptera. The mean number of UV-sensitive prey was 4.4?±?3.6 in webs with stabilimenta compared with 1.8?±?2.1 in webs without stabilimenta. Webs with and without stabilimenta did not differ in the mean number of UV-nonsensitive prey captured. The linear stabilimentum showed strong positive effects on the interception of large prey: webs with stabilimenta captured more than twice as many large prey (≥5?mm) than webs without stabilimenta, whereas there was only a slight difference in the interception rates for small prey (<5?mm). Comparisons among different Argiope species suggest that the stabilimentum may have different adaptive functions in different species or ecological contexts.     

Inclusion of pressure hazards into NFPA 704 instability rating system

The lack of awareness in identifying potential hazardous reactions is commonly cited as a cause of accidents. One major problem is the lack of consensus to assign appropriate reactivity hazards ratings. NFPA 704 instability rating system is widely used throughout the chemical industry. However, this system does not take into account pressure hazards. Inclusion of pressure hazards into the NFPA 704 instability rating will provide a more comprehensive rating system, which will characterize hazards that may arise not only from exothermic reactions, but also from endothermic decompositions with gas evolution. In this work we present a proposed method for developing a simple methodology to include pressure and pressure rates into the assignment of instability ratings. The current NFPA 704 instability rating number for the systems studied does not show a trend between the pressures and pressure rates generated with the assigned rating. Therefore, arbitrary threshold values were chosen to rank the substances according to the pressure and pressure rate generated. Results obtained from a variety of systems with endothermic decompositions show that their pressure and pressure rates have magnitudes comparable to systems that decompose exothermically. So far, this method has been applied only to a limited set of data. However, assignment of arbitrary values for normalized maximum pressures generated and pressure rates, taking as reference the values obtained for the thermal decomposition of cumene hydroperoxide and di-terbutyl peroxide appears to give reasonable limits for the rating chemicals based on their relative pressure hazards.     

Feasibility of biochar application on a landfill final cover—a review on balancing ecology and shallow slope stability

Due to the increasing concerns on global warming, scarce land for agriculture, and contamination impacts on human health, biochar application is being considered as one of the possible measures for carbon sequestration, promoting higher crop yield and contamination remediation. Significant amount of researches focusing on these three aspects have been conducted during recent years. Biochar as a soil amendment is effective in promoting plant performance and sustainability, by enhancing nutrient bioavailability, contaminants immobilization, and microbial activities. The features of biochar in changing soil physical and biochemical properties are essential in affecting the sustainability of an ecosystem. Most studies showed positive results and considered biochar application as an effective and promising measure for above-mentioned interests. Bio-engineered man-made filled slope and landfill slope increasingly draw the attention of geologists and geotechnical engineers. With increasing number of filled slopes, sustainability, low maintenance, and stability are the major concerns. Biochar as a soil amendment changes the key factors and parameters in ecology (plant development, soil microbial community, nutrient/contaminant cycling, etc.) and slope engineering (soil weight, internal friction angle and cohesion, etc.). This paper reviews the studies on the production, physical and biochemical properties of biochar and suggests the potential areas requiring study in balancing ecology and man-made filled slope and landfill cover engineering. Biochar-amended soil should be considered as a new type of soil in terms of soil mechanics. Biochar performance depends on soil and biochar type which imposes challenges to generalize the research outcomes. Aging process and ecotoxicity studies of biochar are strongly required.     

Catalytic Activity of Biomorphic α-MoO(3) in the Degradation of Methyl Violet Dye

A network of fibers comprising orthorhombic molybdenum trioxide (α-MoO(3)) crystals were synthesized using paper as template via a biomorphic approach. The template was completely removed by annealing the sample at 600°C for 5?min. Monoclinic MoO(3) was formed and consequently converted into orthorhombic α-MoO(3) after prolonged annealing. Three milligrams of the biomorphic α-MoO(3) could degrade up to 90% of a methyl violet aqueous solution with a concentration of 20?mg/L under normal visible light. The size of the α-MoO(3) grains and the porosity of the biomorphic sample affected catalytic performance.     

Gas permeability of biochar-amended clay: potential alternative landfill final cover material

Compacted biochar-amended clay (BAC) has been proposed as an alternative landfill final cover material in this study. Biochar has long been proposed to promote crop growth, mitigate odor emission, and promote methane oxidation in field soils. However, previous studies showed that soil-gas permeability was increased upon biochar application, which will promote landfill gas emission. The objective of the present study is to investigate the possibility of using compacted BAC as an alternative material in landfill final cover by evaluating its gas permeability. BAC samples were prepared by mixing 425-μm-sieved peanut shell biochar with kaolin clay in different ratios (0, 5, 10, and 15 %, w/w) and compacting at different degrees of compactions (DOC) (80, 85, and 90 %) with an optimum water content of 35 %. The gas permeability of the BACs was measured by flexible wall gas permeameter and the microstructure of the BACs was analyzed by SEM with energy-dispersive x-ray spectroscopy (EDX). The results show that the effects of biochar content on BAC gas permeability is highly dependent on the DOC. At high DOC (90 %), the gas permeability of BAC decreases with increasing biochar content due to the combined effect of the clay aggregation and the inhibition of biochar in the gas flow. However, at low DOC (80 %), biochar incorporation has no effects on gas permeability because it no longer acts as a filling material to the retard gas flow. The results from the present study imply that compacted BAC can be used as an alternative final cover material with decreased gas permeability when compared with clay.     

Development of freshwater sediment management standards for organic matters, nutrients, and metals in Korea

Korean water quality managers are required to promptly develop national assessment standards for freshwater sediment quality due to the Four Major River Restoration Project in Korea in 2009. We conducted this study to develop sediment management standards (SMSs), determining obviously and severely polluted sediment, which could have adverse impacts on water quality and aquatic ecosystem. The SMSs values were derived from the 95th percentile of concentration distribution for organic matter and nutrients in sediment quality database. For the SMSs of metals, foreign sediment quality guidelines (SQGs) were adopted. As a result, 13 % for loss on ignition (LOI), 1,600 mg/kg for total phosphorus (TP), and 5,600 mg/kg for total nitrogen (TN) were set as the SMSs for freshwater sediment in Korea. These values were higher than the range of heavily polluted sediment from USEPA Region 5 guideline derived by the similar approaches for the Great Lakes harbor sediments, and similar or lower than the severe effect level (SEL) from provincial sediment quality guideline (PSQG) of Ontario, Canada by screening level concentration (SLC) approach. However, SMSs in the present study are appropriate considering the concentration ranges and the Korean SMSs’ definition for freshwater sediments in Korea. The Puget Sound marine sediment cleanup screening level (CSL) in Washington State, USA were adopted as the Korean SMSs for As (93 mg/kg), Cd (6.7 mg/kg), Cr (270 mg/kg), Cu (390 mg/kg), Pb (530 mg/kg), and Zn (960 mg/kg) in freshwater sediments. Hg concentration (0.59 mg/kg) of CSL was too low to determine the polluted freshwater sediments in Korea, and the SEL of Ontario, Canada for mercury concentration (2 mg/kg) was selected as the SMS for Hg. These values were found reasonable through the assessment of applicability with the datasets from locations directly affected by obvious point sources. These results indicate that SMSs for organic matter, nutrient, and metals derived within the present study can successfully determine obviously and severely polluted sediment in Korea. However, the SMSs have limits to specifically determine the effects of polluted sediment on water quality and aquatic ecosystem in Korea. Thus, we will revise and specify SMSs considering those effects and further sediment quality assessment framework in the near future.