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291.
There is an unprecedented production of plastic that is accelerating its disposal while affecting the fitness of the terrestrial as well as the aquatic environment. The term microplastics refers to plastic fragments that are less than 5 mm in size and are widely distributed in the environment. Therefore, the present study intends to explore the biological response of earthworms (Eisenia fetida) toward different concentrations of low-density polyethylene. E. fetida treated with low-density polyethylene concentration (Control), 250 mg kg−1, 1000 mg kg−1, 6000 mg kg−1, 12,000 mg kg−1, and 25,000 mg kg−1. The above ratios were thoroughly mixed with 1kg of artificial soil and tested for growth, reproduction (cocoons and hatchling count), and enzymatic activities namely superoxide dismutase, guaiacol peroxidase, glutathione-S-transferase, and glutathione reductase and molecular docking studies. No mortality was observed during the exposure period at any concentrations. On the 28th day, when compared to the control the highest decrease in body weight of earthworms was observed in 25,000 mg (28.4%) followed by 12,000 mg (12.2%) and 6000 mg (3.4%). The cocoon and hatchlings significantly declined as the dose of microplastics increases. Enzymatic activity such as SOD and POD showed declined trend as the dose increased, while GST and GR increased with an increase in microplastic concentrations on 28th day. Furthermore, molecular docking showed that LDPE can modulate the activity of all four enzymes significantly.  相似文献   
292.
In the present study we examine status, impact and trends in prevailing situation of coastal ecosystem of Chavara, Neendakara, Tangasseri and Paravur zones of Kollam coast in terms of zooplankton density and petroleum hydrocarbon content (PHC). Zooplankton samples and water samples were collected during the period May 2003 to June 2004. The numerical count of zooplankton made and PHC content estimated. Paravur offshore recorded the maximum zooplankton count (1390 no./m3) and Tangasseri nearshore the lowest (700.5 no/m3). The petroleum hydrocarbon content was highest at Tangasseri nearshore (21.95 microg/l) and lowest at Paravur offshore (9.40 microg/l). We also observe statistically significant negative correlation between zooplankton density and PHC for a few organisms. The overall impact appears minor, yet, coastal ocean monitoring imperative for sustainable development.  相似文献   
293.
Accumulation of Pb, Fe, Cr, Zn, Cd, Ni, Cu and Hg metals in six common lichen species growing on Mangifera indica trees in mango orchard surrounding the north side of the Lucknow city, were analyzed. The study revealed the higher concentration of Pb (3.3 - 15.6 microgg(-1)), Cr (25.6 - 137.5 microgg(-1)), Zn (49.4 - 219.7 microgg(-1)), Cu (10.2 - 66.6 microgg(-1)) and Fe (1748 - 19374 microgg(-1)).  相似文献   
294.
Extraction and quantification of pesticide residue from the milk matrix at or below the established maximum residue limit (MRL) is a challenging task for both analytical chemists and the regulatory institutions to take corrective actions for the human health and safety. The main aim of the study is to develop a simple rapid and less expensive QuEChERS extraction and cleanup method for simultaneous analysis of 41 multiclass pesticide residue in milk by gas chromatography-electron capture detector (GC-ECD), followed by confirmation of the residues with gas chromatography-mass spectrometer (GC-MS). Effect of sorbent type, temperature, spiking concentration, matrix effect (ME), measurement uncertainty (MU), inter- and intra-assay repeatability, reproducibility of recovery, and trueness of the results were investigated to validate the effectiveness of the method. Limit of determination (LOD) and limit of quantitation (LOQ) for all the analytes ranged within 0.001–0.02 and 0.002–0.05 µg mL?1, respectively. The % recovery of all the pesticides ranged between 91.38 and 117.56% with relative standard deviation (RSD) below 2.79%. The MU for all the analytes was ≤29% of respective LOQs, and except for few pesticides, the ME was largely negative. The method fulfilled all the SANTE guidelines and thus can be extended for routine analysis of multiclass pesticide residue in milk.  相似文献   
295.
Loss of green cover, and increasing pollution is a prime global concern. The problem calls for screening of pollution-tolerant tree species that can be integrated into plantation drives. Recognizing this, the study analyzed bio-indicator responses and performance of commonly occurring plant species along a pollution gradient in western Himalaya. Based on distance from the road, three sites viz., highly polluted (HP), moderately polluted (MP), and least polluted (LP), were identified. From these sites, leaves of commonly occurring 26 tree species were collected and analyzed for dust accumulation, total chlorophyll, relative water content (RWC), ascorbic acid, and pH using standard protocols. Later, assessment of Air Pollution Tolerance Index (APTI) and Anticipated Performance Indices (API) was carried out. The results revealed variations in biochemical characteristics. The pH, RWC, and total chlorophyll increased with decreasing pollution while ascorbic acid increased with increasing pollution. Dust capturing potential of Ficus carica (1.191 mg/m2) and Toona ciliata (0.820 mg/m2) was relatively higher. Based on the results of APTI, Grevillea robusta was classified as tolerant. It scored significantly higher values (21.06, 21.19, and 19.61 in LP, MP, and HP sites, respectively). Quercus floribunda, G. robusta (68.75% each), Juglans regia (68.7%), and T. ciliata (62.50%) were good performers in HP sites. Acer caesium, Betula utilis, and Morus alba that had low API scores (43.75%) were predicted as poor performers. Thus, G. robusta, Q. floribunda, J. regia, T. ciliata, and F. carica were evaluated as best performers. They could be integrated into plantations drives for environmental management.  相似文献   
296.
In the present study, the flocculation behavior of crosslinked copolymer GrA-cl-poly(AAm) hydrogel has been studied for the removal of turbidity from waste water. Sodium borohydride has been used for the reduction of the Gum rosin acids by which it gets converted into rosin alcohols. The reduced Gum rosin alcohol was crosslinked by the use of MBA and copolymerized with acrylamide using KPS as a redox initiator. Synthesized sample was then optimized for reaction conditions like reaction time, reaction temperature and the amount of solvent, monomer concentration, initiator concentration and pH of the reaction medium in order to get maximum percentage swelling. Synthesized samples were characterized using Fourier transform infrared spectroscopy, scanning electron of microscopy and X-ray diffraction techniques. Response surface methodology (RSM) based central composite design was used to study the effect of pH of swelling medium and temperature to maximize the percentage swelling. A statistical model (ANOVA) predicted pH 7.0 and temperature 40?°C as optimum operating conditions in order to get maximu swelling. GrA-cl-poly(AAm) hydrogel was found to be pH and temperature sensitive. Kaolin has been employed as a coagulant. The flocculation efficiency of the synthesized polymer was studied as a function of polymer dose, temperature and pH of the solution. GrA-cl-poly(AAm) observed to show maximum flocculation efficiency (95%) with 70mgL?1 polymer dose in pH 5.0 at 30?°C. The adsorption capacity of malachite green dye removal (95%) was also studied with this synthesized polymer. The results validate that GrA-cl-poly(AAm) hydrogel has significant flocculation and dye removal properties and can be employed as an effective and low-cost material for removal of impurities from waste water.  相似文献   
297.
In the present study, potential health risks posed to human population from Ropar wetland and its vicinity, by consumption of inorganic arsenic (i-As) via arsenic contaminated rice grains and groundwater, were assessed. Total arsenic (t-As) in soil and rice grains were found in the range of 0.06–0.11 mg/kg and 0.03–0.33 mg/kg, respectively, on dry weight basis. Total arsenic in groundwater was in the range of 2.31–15.91 μg/L. i-As was calculated from t-As using relevant conversion factors. Rice plants were found to be arsenic accumulators as bioconcentration factor (BCF) was observed to be >1 in 75% of rice grain samples. Further, correlation analysis revealed that arsenic accumulation in rice grains decreased with increase in the electrical conductivity of soil. One-way ANOVA, cluster analysis and principal component analysis indicated that both geogenic and anthropogenic sources affected t-As in soil and groundwater. Hazard index and total cancer risk estimated for individuals from the study area were above the USEPA limits of 1.00 and 1.00 × 10?6, respectively. Kruskal-Wallis H test indicated that groundwater intake posed significantly higher health risk than rice grain consumption (χ 2(1) = 17.280, p = 0.00003).  相似文献   
298.
In human-populated landscapes worldwide, domestic dogs (Canis lupus familiaris) are the most abundant terrestrial carnivore. Although dogs have been used for the protection of livestock from wild carnivores, they have also been implicated as predators of livestock. We used a combination of methods (field surveys, interview surveys, and data from secondary sources) to examine the patterns and factors driving livestock depredation by free-ranging dogs, as well as economic losses to local communities in a Trans-Himalayan agro-pastoralist landscape in India. Our results show that livestock abundance was a better predictor of depredation in the villages than local dog abundance. Dogs mainly killed small-bodied livestock and sheep were the most selected prey. Dogs were responsible for the majority of livestock losses, with losses being comparable to that by snow leopards. This high level of conflict may disrupt community benefits from conservation programs and potentially undermine the conservation efforts in the region through a range of cascading effects.  相似文献   
299.
The effect of 24-epibrassinolide seed soaking on imidacloprid residues in green pods and mature seeds of Brassica juncea L. plants was investigated. The activities of the antioxidative enzymes glutathione-S-transferase, glutathione peroxidase, glutathione reductase, ascorbate peroxidase and guaiacol peroxidase, and the content of glutathione were determined. Imidacloprid residues in green pods were analyzed and quantified by gas chromatography-mass spectrometry, revealing that 24-epibrassinolide treatment resulted in a decrease of residues by almost 30%. In mature seeds, no pesticide residues were detected. Activities of all the antioxidative enzymes and glutathione content were found to be high in plants grown in soil amended with 300 mg imidacloprid kg?1 soil, but pre-soaking with 100 nmol L?1 24-epibrassinolide further enhanced the activities of all these enzymes and the glutathione content.  相似文献   
300.
Journal of Material Cycles and Waste Management - The study deals with the management of deoiled rice bran by converting it into ethanol using a multi-enzyme preparation produced in-house...  相似文献   
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