Efficiency and degradation products elucidation of the photodegradation of mefenpyrdiethyl in water interface using TiO2 P-25 and Hombikat UV100

The photodegradation of mefenpyrdiethyl (MFD), an herbicide safener, was investigated in aqueous suspensions by using Degussa P-25 and Hombikat UV100 titanium oxide under simulated sunlight irradiation. The effects of initial concentration of the herbicide, pH, catalysts and hydrogen peroxide doses as well as their combinations were studied and optimized. Accordingly, the kinetic parameters were determined and the effectiveness of the processes was assessed by calculating the rate constants. A pseudo first-order kinetics was observed. Under experimental conditions, the degradation rate constants were strongly influenced using P-25 and no noticeable effect was observed for Hombikat UV100. DFT calculations with B3LYP/6-311+G(2d,p)//B3LYP/6-31+G(d,p) level of theory were performed to check whether significant conformational changes occur when the charge state of the MFD substrate changes and whether these changes could play a role in the dependency of photodegradation rate constant on the studied pH. High resolution mass spectrometry (FT-ICR/MS) was implemented to identify the main degradation products.     

Animal Killing and Postdomestic Meat Production

The act of animal killing affects the human psyche in manners that are culturally contingent. Throughout history, societal attitudes towards the taking of animal lives have mostly been based on deference and/or dominion. Postdomestic societies have evolved in fundamentally different ways. Meat production is abundant yet concealed, animals are categorized and stereotyped, and slaughter has become a highly disquieting activity. Increased awareness of postdomestic meat production systems raises a moral polemic and provokes disgust in some consumer segments. Overall, a heterogeneous set of solutions has emerged to deal with the societal upset and cognitive dissonance caused by animal slaughter. This includes the so-called carnism approach, a rise in animal welfare programs, a market demand for reassuring narratives (“story meat”), a rehabilitation of the metier of farmers and butchers, crowd butchering, neo-ritualism and home slaughter, the biotechnological exploration of “cultured meat” and “pain-free meat”, entomophagy, “meatless meat”, and the increasing proliferation of vegan and vegetarian lifestyles.     

The structure of work values: A cross cultural comparison

Several years ago a research project on work values was originated. The study strived to examine the relative importance of work value items and to analyze the structure of the domain for samples from various cultural environments. A facet definition of work values was suggested that provided guidelines for constructing the Work Values Questionnaire and the formulation of hypotheses regarding the structure of relationships among components of work values. Based on data collected from 2280 respondents in eight countries the hypotheses were tested by means of Guttman's Smallest Space Analysis. The results support the hypotheses. An empirical double-ordered conceptual system, a radex structure, was obtained in each of the samples reflecting the facets of the definition: modality of outcome — cognitive, affective and instrumental, and system - performance contingency — reward, resource. In terms of the issue of cultural differences the results indicate the presence of cultural differences in the rating of a limited number of specific values. These differences are only minor variations within a much broader pattern of structural similarity. The fact that essentially the same structure was obtained in eight independent samples lends substantial support to the definitional framework of work values suggested.     

Connected fragmented habitats facilitate stable coexistence dynamics

In this paper we endeavor to test the controversial ideas that exist about the role of fragmentation in a conservation context. In line with earlier understanding, we find that habitat fragmentation alone results in a strong detrimental effect (especially for the predator population). Connecting the fragmented habitats facilitates predator survival and hence prey survival as compared to the unconnected fragmented case. Our main result is counterintuitive: in the presence of a high quality predator, connected fragmented habitats ensure a better chance for coexistence than does even the unfragmented case. We explain why a connected fragmented habitat might thus be beneficial for the stabilization of the system, and how connections between sub-habitats are able to protect prey population from over-exploitation. In the model, habitat fragmentation is separated from the effects of habitat destruction, in order to better understand how populations react to habitat transformation.     

Impact of market reforms on future patterns of non-ferrous metal consumption of the former Soviet Union

The study examines the implications of market-oriented reforms on the prospects of non-ferrous metal use in the former USSR. Past metal consumption behaviour of the USSR is found to differ considerably from prevailing patterns of the advanced market economies. The study estimates a large 'intensity- of-use' gap across metals, which can be taken as a relatively easily mobilizable source for efficiency improvements via market reforms. Two scenarios for economic reforms are modelled, notably radical and gradual. Both are shown to cause a collapse of varying intensity in domestic metal demand lasting until the mid-1990s. For the subsequent period, a turnaround in consumption trends is projected, which is sharper under the radical reform scenario. The projected collapse of domestic demand argues for an increasing exportable surplus in the former Soviet Union for a range of non-ferrous metals, with potentially severe depressive effect on world prices.     

Dual Objective Control of Nutrient Loading into a Lake1

ABSTRACT: The control of nutrient loading into a water body is approached from a multiobjective viewpoint. The example of phosphorus (P) loading into Lake Balaton, Hungary, is used as a case study. The element P is chosen because it appears to be the limiting factor of eutrophication in the lake considered, as in many other lakes. About one-half of P loading originates from nonpoint sources; furthermore, the mechanism is poorly known and only few observation data are available. The objective of eutrophication control is to minimize P loading, while the objective of watershed management is to maximize agricultural revenue. These two objectives often appear to be in conflict. A discrete set of alternative control methods is defined, consisting in controlling a mix of the following elements: point sources, runoff, fertilizer type and application, cropping management, erosion, and sedimentation. The system dynamics is provided by a previously developed stochastic model, whose output is an empirical prohability density function (pdf) of P-loading reflecting the control policy. A compromise solution of “satisfactum” can then be chosen as a mix of the best ranked policies.     

Progestogen-induced alterations and their ecological relevance in different embryonic and adult behaviours of an invertebrate model species,the great pond snail (Lymnaea stagnalis)

Environmental Science and Pollution Research - The presence of oral contraceptives (basically applying estrogens and/or progestogens) poses a challenge to animals living in aquatic ecosystems and...     

Total mercury and methylmercury in freshwater and salt marsh soils of the Mississippi river deltaic plain

Mercury entering wetland environments can be microbially methylated to methylmercury. The purpose of this study was to investigate the historical rate of mercury accumulation and distribution of total and methylmercury in soil profile of Louisiana coastal marshes. Two sediment cores each were taken from Louisiana freshwater marsh and salt marsh. Vertical accretion was determined using the 137Cs dating technique. Total and methylmercury were determined with depth in the soil profiles. The fresh marsh soil on a dry weight basis contained more total and methylmercury than the salt marsh. Average vertical accretion rates in freshwater marsh and salt marsh were 0.90 and 0.75 cm year(-1), respectively. Average total and methylmercury content (to a depth of 30 cm) was 140 and 4.19 microg kg(-1) and 80 and 1.34 microg kg(-1) for the fresh and salt marsh, respectively. Due to greater sediment input resulting in a higher bulk density the salt marsh contained more total mercury per m2 (to 30 cm depth) than the fresh water marsh (5340 microg m(-2) as compared to 2929 microg m(-2)). The amount of methylmercury per m2 to depth of 30 cm was approximately the same for each marsh.     

Indoor and outdoor air concentrations of BTEX and NO2: correlation of repeated measurements

Studies on health effects of air pollutants ideally define exposure through the collection of air samples in the participants' homes. Concentrations derived from these samples are then considered as an estimate for the average concentration of air pollutants in the homes. Conclusions drawn from such studies therefore depend very much on the validity of the measured air pollution concentrations. In this paper we analysed repeated BTEX and NO(2) measurements with a time period of several months lying between the two conducted home visits. We investigated the variability of their concentrations over time by determining correlation coefficients and calculating within- and between-home variances. Our population consisted of 631 homes of participants from two cohort studies within the framework of the German study on Indoor Factors and Genetics in Asthma. Air pollutants were measured using passive samplers both indoors and outdoors. The measured BTEX concentrations were poorly correlated, with Pearson's correlation coefficient r ranging from -0.19 to 0.27. Additionally, a considerable seasonal effect could be observed. A higher correlation was found for the NO(2) concentrations with r ranging between 0.24 and 0.55. For the BTEX, the between-home variance was bigger than the within-home variance, for NO(2) both variances were of about the same order. Our results indicate that in a setting of moderate climate like in Germany, the variability of BTEX and NO(2) concentrations over time is high and a single measurement is a poor surrogate for the long-term concentrations of these air pollutants.