Effect of trichloroethylene (TCE) inhalation on biotransformation enzymes of rat lung and liver

Trichloroethylene (TCE) is widely used as an industrial solvent and cleaning fluid. In the present study the toxic effects of TCE inhalation on pulmonary and hepatic biotransformation enzymes in rats have been investigated by assay of aniline hydroxylase (AH), aminopyrine-N-demethylase (APD), benzo-a-pyrene hydroxylase (BH) and glutathione-s-transferase (GST) activities and glutathione (GSH) contents in liver as well as lungs of exposed animals. In both organs phase I and phase II drug metabolizing enzymes have been found to be increased along with decrease in GSH contents following TCE inhalation. Pulmonary as well as hepatic MFO's seem to be activated by inhaled TCE probably in an attempt for its rapid detoxification and reduced glutathione is used during its biotransformation.     

Regional inventory of soil surface nitrogen balances in Indian agriculture (2000-2001)

Nitrogen regulates several ecological and biogeochemical processes and excess reactive nitrogen in the environment can lead to pollution problems, including the deterioration of air quality, disruption of forest processes, acidification of lakes and streams, and degradation of coastal waters. Much of the excess nitrogen inputs are related to food and energy production. An important step to understanding the sources of nitrogen and ultimately defining solutions to excess nitrogen is to describe the geographic distribution of agricultural nitrogen contributions from different regions. In this study, soil surface nitrogen loads were quantified for different states of India for the period 2000-2001. Nearly 35.4 Tg of nitrogen has been estimated as inputs from different sources, with output nitrogen from harvested crops of about 21.20 Tg. The soil surface nitrogen balance, estimated as inputs minus outputs, is found to be about 14.4 Tg surplus from the agricultural land of India. Livestock manure constituted a major percentage of total inputs (44.06%), followed by inorganic fertilizer (32.48%), atmospheric deposition (11.86%) and nitrogen fixation (11.58%). Nitrogen balance varied from deficit to surplus for different states. The highest nitrogen surplus was found in Uttar Pradesh (2.50 Tg) followed by Madhya Pradesh (1.83 Tg), Andhra Pradesh (1.79 Tg), etc. A negative nitrogen balance was found in Orissa (-0.01 Tg), Andaman Nicobar Islands (-0.32 Tg) and for some of the northeastern states. Major fertilizer consumption states were found to be Tamilnadu (204 kg/ha), Haryana (132 kg/ha), Punjab (148 kg/ha), followed by others. Similarly, nitrogen inputs from total livestock excretions were found to be high for Kerala (616 kg/ha), Jammu and Kashmir (389 kg/ha), Tamil Nadu (338 kg/ha), etc. The average nitrogen surplus of about 54 kg/ha observed for the agricultural land of the entire country of India is comparatively higher than the average surplus of about 31 kg/ha reported for European countries. These results, obtained from nutrient mass balance calculations, will be useful to formulate nutrient management plans relating to fertilizer usage, livestock management and for adopting some best management strategies at a state level in India.     

Plant community tolerant to trace elements growing on the degraded soils of São Domingos mine in the south east of Portugal: environmental implications

The selection of trace element tolerant species is a key factor to the success of remediation of degraded mine soils. Mining activities generate a large amount of waste rocks and tailings, which get deposited at the surface. The degraded soils, the waste rocks and tailings are often very unstable and will become sources of pollution. The direct effects will be the loss of cultivated land, forest or grazing land, and the overall loss of production. The indirect effects will include air and water pollution and siltation of rivers. These will eventually lead to the loss of biodiversity, amenity and economic wealth. Restoration of a vegetation cover can fulfil the objectives of stabilization, pollution control, visual improvement and removal of threats to human beings. Thus, remediation of mine spoils/tailings and biogeochemical prospecting would rely on the appropriate selection of plant species. Plant community responds differently on their ability to uptake or exclude a variety of metals. In this work, plant species were sampled from all populations established in an abandoned copper mine of S?o Domingos, SE Portugal. Plants belonging to 24 species, 16 genera and 13 families were collected from the degraded copper mine of S?o Domingos. Plant samples were analysed for total Ag, As, Cu, Ni, Pb, and Zn. The highest concentrations of metals in soils dry matter were 11217.5 mg Pb kg(-1), 1829 mg Cu kg(-1), 1291 mg As kg(-1), 713.7 mg Zn kg(-1), 84.6 mg Cr kg(-1), 54.3 mg Co kg(-1), 52.9 mg Ni kg(-1) and 16.6 mg Ag kg(-1). With respect to plants, the higher concentrations of Pb and As were recorded in the semi-aquatic species Juncus conglomeratus with 84.8 and 23.5 mg kg(-1) dry weight (DW), Juncus efusus with 22.4 and 8.5 mg kg(-1) DW, and Scirpus holoschoenus with 51.7 and 8.0 mg kg(-1) DW, respectively. Thymus mastichina also showed high content of As in the aboveground parts, 13.6 mg kg(-1) DW. Overall, the results indicate accumulation of various metals by different plant species, with some of these metals being partitioned to the shoots. Environmental implications of these observations are discussed.     

Optimization of ambient Air Quality Monitoring Networks

A method has been developed to obtain a joint solution to the problem of optimum number and configuration of ambient air quality monitors, on the principles of spatial correlation analysis and the minimum spanning tree. The interest in this case is to represent the patterns of regional air quality, at a minimum of an overlap of information. This methodology is extended to account for the uncertainties in air quality simulations and also to incorporate the probabilities of occurrence. As an illustration to these methodologies, an example of Taipei City, Taiwan has been considered.     

Demographic antecedents and performance consequences of structural holes in work teams

This paper addresses two important questions concerning social fragmentation in work teams. First, from where do disconnections between team members, measured in terms of the proportion of structural holes within the work team, derive? Second, what are the consequences for team performance of having more or less structural holes between team members? In answering the first question, the research investigated whether demographic diversity in teams played a role in predicting the proportion of structural holes in team friendship networks. For 19 teams at a wood products company, there were no effects of ethnic and gender diversity on structural hole proportions. However, age diversity significantly reduced the extent of structural ‘holeyness.’ In investigating the second question, two countervailing tendencies were considered. In the absence of structural holes, teams are likely to be at low risk for new ideas. But fragmented teams in which team members are separated by many structural holes are likely to have difficulty coordinating. The researchers demonstrated a curvilinear effect: a moderate level of structural diversity in teams was positively associated with team performance. Thus, the research suggested that it is structural diversity (measured in terms of the proportion of structural holes) rather than demographic diversity that matters in the prediction of team performance. Copyright © 2006 John Wiley & Sons, Ltd.     

Adsorption behavior of benzenesulfonic acid by novel weakly basic anion exchange resins

Two novel weakly basic anion exchange resins(SZ-1 and SZ-2) were prepared via the reaction of macroporous chloromethylated polystyrene-divinylbenzene(Cl-PS-DVB) beads with dicyclohexylamine and piperidine, respectively. The physicochemical structures of the resulting resins were characterized using Fourier Transform Infrared Spectroscopy and pore size distribution analysis. The adsorption behavior of SZ-1 and SZ-2 for benzenesulfonic acid(BA) was evaluated, and the common commercial weakly basic anion exchanger D301 was also employed for comparison purpose. Adsorption isotherms and influence of solution p H, temperature and coexisting competitive inorganic salts(Na2SO4and Na Cl) on adsorption behavior were investigated and the optimum desorption agent was obtained.Adsorption isotherms of BA were found to be well represented by the Langmuir model.Thermodynamic parameters involving ΔH, ΔG and ΔS were also calculated and the results indicate that adsorption is an exothermic and spontaneous process. Enhanced selectivity of BA sorption over sulfate on the two novel resins was observed by comparison with the commercial anion exchanger D301. The fact that the tested resins loaded with BA can be efficiently regenerated by Na Cl solution indicates the reversible sorption process. From a mechanistic viewpoint, this observation clearly suggests that electrostatic interaction is the predominant adsorption mechanism. Furthermore, results of column tests show that SZ-1possesses a better adsorption property than D301, which reinforces the feasibility of SZ-1for potential industrial application.     

Building disaster‐resilient micro enterprises in the developing world

Family‐owned micro enterprises operating within the informal sector of most developing countries provide millions of citizens with a livelihood and are the economic backbone of many communities. Yet, the turbulence that emanates up or down respective supply chains following a disaster can cause these entities to fail. This study develops a model that recognises the relative weakness of micro enterprises to such disaster‐related shocks. The model proposes that micro enterprises can moderate the effect of such shocks by creating resilience through cognitive preparation, continuous learning, and the generation of various forms of social capital (cognitive, relational, and structural). The propositions for the model are established through an extensive literature review, coupled with examples drawn from the documents of humanitarian agencies performing disaster relief work in India. This model also serves as a preliminary basis with which to derive metrics to set benchmarks or to assess the viability of a micro enterprise's ability to survive disaster‐related shocks.     

The relative importance of COVID-19 pandemic impacts on biodiversity conservation globally

The COVID-19 pandemic has had an enormous impact on almost all aspects of human society and endeavor; the natural world and its conservation have not been spared. Through a process of expert consultation, we identified and categorized, into 19 themes and 70 subthemes, the ways in which biodiversity and its conservation have been or could be affected by the pandemic globally. Nearly 60% of the effects have been broadly negative. Subsequently, we created a compendium of all themes and subthemes, each with explanatory text, and in August 2020 a diverse group of experienced conservationists with expertise from across sectors and geographies assessed each subtheme for its likely impact on biodiversity conservation globally. The 9 subthemes ranked highest all have a negative impact. These were, in rank order, governments sidelining the environment during their economic recovery, reduced wildlife-based tourism income, increased habitat destruction, reduced government funding, increased plastic and other solid waste pollution, weakening of nature-friendly regulations and their enforcement, increased illegal harvest of wild animals, reduced philanthropy, and threats to survival of conservation organizations. In combination, these impacts present a worrying future of increased threats to biodiversity conservation but reduced capacity to counter them. The highest ranking positive impact, at 10, was the beneficial impact of wildlife-trade restrictions. More optimistically, among impacts ranked 11-20, 6 were positive and 4 were negative. We hope our assessment will draw attention to the impacts of the pandemic and, thus, improve the conservation community's ability to respond to such threats in the future.     

Analysis of barriers in e-waste management in developing economy: an integrated multiple-criteria decision-making approach

Environmental Science and Pollution Research - An increasing amount of electronic waste (e-waste) is not a new concern. It has been causing trouble globally. This waste comprises valuable metals...     

Pyrene remediation by Trametes maxima: an insight into secretome response and degradation pathway

Environmental Science and Pollution Research - The rapid pace of economic development has resulted in the release of several polycyclic aromatic hydrocarbons (PAHs) into the environment. Microbial...