Influence of humic substances on the toxic effects of cadmium and zinc to the green alga Pseudokirchneriella subcapitata

A method combining (1 h) algal photosynthesis inhibition tests and tangential-flow ultrafiltration (TFF) technique (cut-off 1 kDa) was used to determine the effect of humic substances (HS) on acute metal toxicity to Pseudokirchneriella subcapitata. Three "standard" HS (soil and peat humic acids and Suwannee River fulvic acids) at two concentrations (1 and 5 mg/l) and two metals (Zn at 390 microg/l and Cd at 200 microg/l) were studied. Toxicity of Cd and Zn to P. subcapitata was significantly (p<0.05) reduced in the presence of humic acids (HA) but not in the presence of Suwannee River fulvic acids (SRFA). Metal partitioning between colloidal (1 microm-1 kDa) and truly dissolved (<1 kDa) fractions was found to match a decrease of metal toxicity in the presence of HA, but not in the presence of SRFA. The results suggested that HA reduced Cd and Zn toxicity in two different ways: (1) HA decrease the amount of free metal ions. Metal-HA complexes are high molecular weight, relatively stable with regard to metal-exchange reactions and consequently the metals were less bioavailable. (2) HA adsorbed onto algal surfaces, shielded the cells from free Cd and Zn ions. Several possible explanations can be postulated to account for the observed SRFA results: (1) Cd- and Zn-SRFA complexes are thought to be labile (i.e. undergo rapid dissociation); (2) SRFA coagulated, presumably during equilibration, and that coagulation altered metal complexing behavior of SRFA; (3) FA has a lower ability to adsorb on cell membranes at pH>7.     

Environmental Effects of In Situ Burning of Oil Spills in Inland and Upland Habitats

In situ burning of inland and upland habitats is an alternative oil spill cleanup technique that, when used appropriately, may be more environmentally acceptable than intrusive manual, mechanical, and chemical treatments. There have been few published reports documenting the environmental effects of in situ burning in inland and upland habitats. Thus, this study, sponsored by the American Petroleum Institute, used two approaches to increase the knowledge base and improve the appropriate use of in situ burning: (1) detailed review of published and unpublished in situ burn case histories for inland and upland spills; and (2) summaries of fire effects and other information from the literature on fire ecology and prescribed burning. Thirty-one case histories were summarized to identify the state of the practice concerning the reasons for burning, favorable conditions for burning, and evaluations of burn effects. The fire ecology and effects summaries included information from the extensive knowledge base surrounding wildfire and prescribed burning (without oil) as a natural resource management tool, as well as fire tolerance and burning considerations for dominant vegetation types of the United States. Results from these two approaches should improve the application of in situ burning for inland and upland spills.     

Integrating product quality and environmental performance through innovation—the l'oréal case

Meeting the demands of today's marketplace has become an increasingly complex challenge for corporations in all industries. The consumer is demanding high-quality products, low cost, and more recently, a new variable: environmental performance. Customers will not accept sacrifices in quality or cost to help businesses meet regulatory requirements or develop environmentally sound products. They want it all. Consequently, companies are faced with the complex task of balancing cost, quality, and environmental performance.     

R&D professionals' views of criteria for intrafirm job mobility: Individual and aggregate analyses of transfer climate perceptions in West German and British Industrial R&D Organizations

Prior research on employees' views of various criteria for obtaining a desirable intrafirm transfer has conceptualized these perceptions on an individual level of analysis (i.e. has examined psychological transfer climates). It is argued that the identification of aggregate transfer climate dimensions on an organizational (subsystem) level of analysis is important for improving the effectiveness of R&D via better transfer policies. Factor analyses of questionnaire data obtained from 729 R&D professionals in 11 FRG industrial firms and 141 R&D professionals in three U.K. industrial firms revealed that both FRG and U.K. subjects perceived three broad means (overall task performance, publication and patent productivity, favouritism) for obtaining a desirable job transfer. Empirically the idea was supported that, for certain transfer criteria (overall task performance, manifest professional output, educational level, luck), individuals' scores can be meaningfully aggregated to obtain organizational transfer climate measures. Remarkable differences in the importance of company tenure and educational level as criteria for transfers in R&D were found between FRG and U.K. organizations. Using the FRG data set differences in the performance responsiveness of organizational transfer climates were shown to be significantly related to work-related outcome variables. Implications are sketched for R&D transfer policies and for explaining U.K./FRG differences in the corporate treatment of R&D activities.     

Cardiovascular risk under electromagnetic exposure in physiotherapy

The aim of the study was to assess the long-term effects of electromagnetic radiation (EMR) on cardiovascular system of medical staff in physiotherapy. A number of 52 exposed subjects (4 male and 48 female; aged 47.3 ± 8.7 years), and a control group of 52 subjects, matched by sex and age, with similar job characteristics without EMR exposure were studied. The EMR exposure from devices emitting at 50 Hz, 150 kHz, 27.12 MHz, 2.45 GHz, and optical radiation was assessed. The relative values of EMR for the whole frequency range in each physiotherapy were calculated and the obtained quota was much larger than 1. The workload and psychosocial factors were evaluated, too. The cardiovascular risk factors arterial pressure, lipid profile, body mass index, waist/hip ratio, smoking, alcohol consumption, nutrition, family history of cardiovascular disease were studied. The incidence of hypertension was moderate with the studied physiotherapists (26.9% v.s. 23.8% control group). The total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were significantly higher in the exposed group. The odds ratios indicate higher possibility of becoming dyslipidemic for the exposed to EMR subjects [for TC OR (95% CI) = 1.570 (1.048–2.351) and for LDL-C OR (95% CI) = 1.840 (1.158–2.924)]. In conclusion, our data show that the EMR exposure of the medical staff in physiotherapy could be associated with the adverse effects on cardiovascular system.     

Degradation of 14C-glyphosate and aminomethylphosphonic acid (AMPA) in three agricultural soils

Glyphosate (N-phosphonomethyl glycine) is the most used herbicide worldwide. The degradation of 14C-labeled glyphosate was studied under controlled laboratory conditions in three di erent agricultural soils: a silt clay loam, a clay loam and a sandy loam soil. The kinetic and intensity of glyphosate degradation varied considerably over time within the same soil and among di erent types of soil. Our results demonstrated that the mineralization rate of glyphosate was high at the beginning of incubation and then decreased with time until the end of the experiment. The same kinetic was observed for the water extractable residues. The degradation of glyphosate was rapid in the soil with low adsorption capacity (clay loam soil) with a short half-life of 4 days. However, the persistence of glyphosate in high adsorption capacity soils increased, with half-live of 19 days for silt clay loam soil and 14.5 days for sandy loam soil. HPLC analyses showed that the main metabolite of glyphosate, aminomethylphosphonic acid (AMPA) was detected after three days of incubation in the extracts of all three soils. Our results suggested that the possibility of contamination of groundwater by glyphosate was high on a long-term period in soils with high adsorption capacity and low degrading activities and/or acid similar to sandy loam soil. This risk might be faster but less sustainable in soil with low adsorption capacity and high degrading activity like the clay loam soil. However, the release of non-extractable residues may increase the risk of contamination of groundwater regardless of the type of soil.     

Geometric morphometrics as a tool for improving the comparative study of behavioural postures

Describing postures has always been a central concern when studying behaviour. However, attempts to compare postures objectively at phylogenetical, populational, inter- or intra-individual levels generally either rely upon a few key elements or remain highly subjective. Here, we propose a novel approach, based on well-established geometric morphometrics, to describe and to analyse postures globally (i.e. considering the animal’s body posture in its entirety rather than focusing only on a few salient elements, such as head or tail position). Geometric morphometrics is concerned with describing and comparing variation and changes in the form (size and shape) of organisms using the coordinates of a series of homologous landmarks (i.e. positioned in relation to skeletal or muscular cues that are the same for different species for every variety of form and function and that have derived from a common ancestor, i.e. they have a common evolutionary ancestry, e.g. neck, wings, flipper/hand). We applied this approach to horses, using global postures (1) to characterise behaviours that correspond to different arousal levels, (2) to test potential impact of environmental changes on postures. Our application of geometric morphometrics to horse postures showed that this method can be used to characterise behavioural categories, to evaluate the impact of environmental factors (here human actions) and to compare individuals and groups. Beyond its application to horses, this promising approach could be applied to all questions involving the analysis of postures (evolution of displays, expression of emotions, stress and welfare, behavioural repertoires…) and could lead to a whole new line of research.