Changes of hematological parameters in Prochilodus lineatus (Pisces, Prochilodontidae) exposed to sublethal concentration of cypermethrin

Freshwater fish Prochilodus lineatus were exposed to sublethal concentrations of cypermethrin (0.3 and 0.6 microg/l) for 2, 5 and 8 days. It was observed that with the increase of exposure time total erythrocyte (RBC), hemoglobin (Hb), hematocrit (Ht) and mean corpuscular hemoglobin concentration (MCHC) values decreased but mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) values increased. These reports indicate that hematological parameters, may be useful as a diagnostic test for cypermethrin exposure in aquatic organisms.     

Agricultural soil as a potential source of input of organochlorine pesticides into a nearby pond

A study was conducted in the southeastern region of Buenos Aires province, Argentina, to assess an agricultural soil as a potential source of organochlorine (OC) pesticides for the aquatic biota of a nearby pond. We analyzed gamma-HCH (lindane), still in use, and the following banned compounds: DDT, DDE, DDD heptachlor, heptachlor epoxide, aldrin, dieldrin and endrin in soil, bulrush, grass shrimp and fish using gas chromatography with electron capture detection (GC-ECD). Among the OC pesticides, lindane was most dominant in the soil (32.6 ng/g dry wt in the upper and 173.9 ng/g dry wt in the lower horizon) and bulrush (1.9 pg/g lipid). Macrophyte also accumulated high levels of heptachlor epoxide (1.5 pg/g lipid). Heptachlor, although present in the soil, was below the detection limit in all aquatic biota studied. Its primary degradation product, heptachlor epoxide, was found in both soil and biota samples. DDT was found at low levels in the surface soil (6.8 ng/g dry wt), but at higher concentrations in fish (3.6 pg/g lipid), although levels were still below permissible levels for human consumption. Since most of the compounds were found in both soil and aquatic biota, our study suggests that agricultural soil could be an important source for OC pesticides in the nearby pond.     

Regaining the traditional use of wildlife in wetlands on the coastal plain of Veracruz,Mexico: ensuring food security in the face of global climate change

Regional Environmental Change - Wetlands play important roles that benefit social-ecological systems. They are threatened by climate change and human activities, i.e., raising livestock and...     

Effect of delayed first feeding on larval performance of the spider crab Maja brachydactyla assessed by digestive enzyme activities and biometric parameters

The effect of food deprivation on larval performance of the spider crab Maja brachydactyla was studied in terms of survival, moulting capacity, size, weight and enzymatic activities. Five feeding treatments that differed in the initial age of first feeding larvae (fed from hatching, 2, 4 and 6 days post-hatching and unfed) were tested for 20 days. Newly hatched larvae kept without food supply lasted for 10 days and did not moult; with 50% survival observed at 6 days post-hatching. Larvae (zoea I stage) were only able to tolerate 2 days of food deprivation after the onset of exogenous feeding without their performance being compromised. Multivariate analyses suggest that digestive enzyme activities may be good indicators of the nutritional condition of larvae.     

Effect of inoculum to substrate ratio (I/S) on municipal solid waste anaerobic degradation kinetics and potential

The goal of this study is to evaluate the impact of the inoculum to substrate ratio (I/S) on the anaerobic degradation potential of municipal solid waste (MSW). Reconstituted MSW samples were thus incubated under batch anaerobic conditions and inoculated with an increasing amount of inoculum originating from a mesophilic sludge digester. I/S tested values were 0 (no inoculum added), 0.015, 0.03, 0.06, 0.12, 0.25, 1, 2 and 4 (gVM_inoculum/gVM_waste). The results indicate that the apparent maximal rate of dissolved organic carbon accumulation is reached at I/S = 0.12. Under this level, the hydrolysis process is limited by the concentration of biomass and can thus be described as first order kinetics phenomena with respect to biomass for I/S ratios below 0.12. The maximum methane production rate and the minimal latency are reached at a ratio of 2. In addition to that, both methane signature and ARISA show a shift in the methanogenic populations from hydrogenotrophic to acetoclastic.     

Emotional labor threatens decent work: A proposal to eradicate emotional display rules

Emotional labor—the management of emotional displays as part of one's work role—has emerged as a growth area of study within organizational behavior and customer service research. In this article, we call attention to the human costs of “service with a smile” requirements with little benefits. We first review the evidence showing that requiring positive emotions from employees induces dissonance and depleted resources, which hinders task performance and threatens well‐being. We articulate how formalized emotion display requirements limit self‐determination by threatening the autonomy, competence, and belongingness needs of employees. Further, via an organizational justice lens, we argue that emotional labor is an unfair labor practice because employees in such circumstances are (1) undervalued by the organization (constituting distributive injustice); (2) disrespected by customers (constituting interactional injustice); and (3) self‐undermined by organizational policies (constituting procedural injustice). We then argue for bringing light to the dark side of emotional labor with a “modest proposal”: Organizations and customers should abandon formalized emotion display expectations and replace such efforts with more humanistic practices that support and value employees, engendering positive climates and an authentically positive workforce. Copyright © 2015 John Wiley & Sons, Ltd.     

Developmental and behavioral effects of embryonic exposure to the polybrominated diphenylether mixture DE-71 in the killifish (Fundulus heteroclitus)

Exposures to penta polybrominated diphenylether (PeBDE) cause neurobehavioral toxicity in developing mice and rats. As levels of these ubiquitous contaminants are increasing in the environment, this raises concern that wildlife may also suffer such effects, with consequences for their ability to catch prey and avoid predators. PeBDE levels in wild-caught fish have been steadily escalating over the past fifteen years. To our knowledge, behavioral consequences of piscine embryonic exposure to PeBDE has not yet been studied. The objectives of this investigation were to characterize effects on development in an environmentally relevant fish model, and test for latent behavioral effects following cessation of exposure. Embryos from the estuarine minnow, Fundulus heteroclitus, were exposed from day 0-7 post fertilization to the industrial PeBDE mixture, DE-71 (0.001 to 100 microg l(-1)). Embryos were assayed for hatching success, development, and microsomal enzyme cytochrome P4501A (CYP1A) activity, which was determined by analysis of in ovo ethoxy-resorufin-O-deethylase (EROD) activation in embryos. Larval fish were assayed for predation ability, activity level, and fright response to a simulated predator. Juvenile fish were assayed for learning ability in a three-chambered fish maze. No induction of embryonic EROD activity was observed, nor was a high dose of DE-71 able to inhibit EROD activity induced by beta-naphthoflavone. No deformities were detected, but a subtle developmental asymmetry with respect to tail curvature direction was observed, and a hatching delay of up to 4.5 days was noted. Behavioral test results suggest that embryonic exposure to DE-71 may alter activity level, fright response, predation rates, and learning ability in subsequent life stages.     

The customer is not always right: customer aggression and emotion regulation of service employees

Research on work aggression or anger has typically focused on supervisors and co‐workers as the instigators of aggression; however, aggressive customers are also likely and may have unique consequences for the employee. We explore this phenomenon with a sample of 198 call center employees at two work sites. The employees reported that customer verbal aggression occurred 10 times a day, on average, though this varied by race and negative affectivity. Using LISREL, our data indicated that both the frequency and stress appraisal of customer aggression positively related to emotional exhaustion, and this burnout dimension mediated the relationship of stress appraisal with absences. Stress appraisal also influenced employees' emotion regulation strategies with their most recent hostile caller. Employees who felt more threatened by customer aggression used surface acting or vented emotions, while those who were less threatened used deep acting. Job autonomy helped explain who found these events more stressful, and implications of these results are discussed. Copyright © 2004 John Wiley & Sons, Ltd.     

Phytoextraction of Pb,Cr, Ni,and Zn using the aquatic plant Limnobium laevigatum and its potential use in the treatment of wastewater

In order to study the bioaccumulation of Pb, Cr, Ni, and Zn and the stress response, the floating aquatic plant Limnobium laevigatum was exposed to increasing concentrations of a mixture of these metals for 28 days, and its potential use in the treatment of wastewater was evaluated. The metal concentrations of the treatment 1 (T1) were Pb 1 μg L⁻¹, Cr 4 μg L⁻¹, Ni 25 μg L⁻¹, and Zn 30 μg L⁻¹; of treatment 2 (T2) were Pb 70 μg L⁻¹, Cr 70 μg L⁻¹, Ni 70 μg L⁻¹, and Zn 70 μg L⁻¹; and of treatment 3 (T3) were Pb 1000 μg L⁻¹, Cr 1000 μg L⁻¹, Ni 500 μg L⁻¹, and Zn 100 μg L⁻¹, and there was also a control group (without added metal). The accumulation of Pb, Cr, Ni, and Zn in roots was higher than in leaves of L. laevigatum, and the bioconcentration factor revealed that the concentrations of Ni and Zn in the leaf and root exceeded by over a thousand times the concentrations of those in the culture medium (2000 in leaf and 6800 in root for Ni; 3300 in leaf and 11,500 in root for Zn). Thus, this species can be considered as a hyperaccumulator of these metals. In general, the changes observed in the morphological and physiological parameters and the formation of products of lipid peroxidation of membranes during the exposure to moderate concentrations (T2) of the mixture of metals did not cause harmful effects to the survival of the species within the first 14 days of exposure. Taking into account the accumulation capacity and tolerance to heavy metals, L. laevigatum is suitable for phytoremediation in aquatic environments contaminated with moderated concentrations of Cr, Ni, Pb, and Zn in the early stages of exposure.

     

The safety observer effect: the effects of conducting safety observations

INTRODUCTION: Some research suggests that conducting safety observations of another's safety performance may serve as an effective tool in increasing the safety performance of the observer. The primary purpose of the present study was to assess the effects of conducting safety observations on the postural safety performance of observers engaging in an assembly task for short time periods. The secondary objectives of the study were: (a) to measure productivity, and (b) to measure the accuracy of participant safety observations. METHOD: An ABC (A: baseline, B: information, C: observation) multiple-baseline design counterbalanced across postural behaviors (back, shoulder, and feet position) was implemented with six participants. RESULTS AND DISCUSSION: Substantial improvements in postural safety occurred after participants conducted safety observations, and these improvements did not appear to negatively affect productivity. Results also suggest that there is no relation between the accuracy of an observer's safety observation and their subsequent safety performance. IMPACT ON INDUSTRY: This research provides evidence that a safety observation process can function to increase safe postural behavior of observers. Thus, the implementation of such a process may contribute to the prevention of musculoskeletal disorders and related costs in the workplace.