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121.
The present study was carried out to observe the possible beneficial effects of Vitamin E, a natural antioxidant on methomyl-induced biochemical and histological alterations in rat liver. To carry out the investigations, animals were segregated in four different groups. Animals in Group I served as normal controls. Animals in Group II were given single methomyl dose orally in water (9 mg kg?1 b.wt). Animals in Group III were injected intraperitoneally with Vitamin E (50 mg kg?1 b.wt) for 1 week on alternate days. Animals in Group IV were administered Vitamin E 1 week before subjecting them to methomyl treatment. Animals in all the groups were sacrificed 24 h after the end of treatments. Different biochemical estimations were carried out, which included estimation of aspartate aminotransaminase (AST), alanine aminotransaminase (ALT), alkaline phosphatase (ALP) and acetylcholinesterase (AChE). Further, to examine the oxidative damage lipid peroxidation (LPO) and glutathione (GSH) levels as well as antioxidant enzymes such as superoxide dismutase (SOD), catalase, glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GSHPx), and glutathione-6-phosphate dehydrogenase were estimated in liver samples. AchE activity was inhibited significantly both in serum and liver following methomyl treatment. Administration of methomyl caused a significant increase in serum AST, ALT and ALP which indicated hepatic damage. LPO was found to be significantly increased, whereas GSH levels were decreased in the liver of methomyl-treated animals. The activities of SOD and catalase were significantly decreased whereas GST and GSHPx activities were found to be elevated significantly following methomyl treatment. No significant change in the enzyme activity of GR and glutathione-6-phosphatase dehydrogenase was observed after methomyl treatment. Vitamin E supplementation was able to attenuate appreciably the methomyl-induced changes in LPO levels along with SOD and GST activities. Histopathological studies following methomyl treatment revealed that hepatocytes, were not very well delineated and nuclei showed degenerative changes. Whereas, following Vitamin E supplementation in combined treatment group nuclei showing degenerative changes become less in number. The study, therefore, concludes that Vitamin E has a potential in mitigating most of the adverse effects induced by methomyl acute toxicity.  相似文献   
122.
The effect of antioxidant rich diet supplements of Spirulina and tamarind fruit pulp at 230 mg kg?1 body weight, separately as well as in combination, on various hematological parameters of Swiss albino mice exposed to fluoride for seven days at daily doses of 190 mg kg?1 body weight and for 90 days at daily doses of 94 mg kg?1 body weight is reported. Compared with controls, fluoride exposure decreased erythrocyte (12%–18%), leukocyte (16%) and platelet counts (7%, only for short-term exposure), hemoglobin (2%–17%) and packed cell volume (2%–14%) in Swiss albino mice reared on standard feed but these were altered little in the diet supplement groups. Fluoride exposure decreased lymphocytes in both standard feed (16%–21%) and diet supplement groups (5%–19%, but only after long-term exposure). Fluoride withdrawal led to recovery of the post-treated mice from long-term exposure. Spirulina alone and also in combination with tamarind fruit pulp was found more effective than tamarind alone in reducing hematological disorders in fluoride treated mice.  相似文献   
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124.
In the present study, performance of the trickle bed airbiofilter (TBAB) for treating mono-chlorobenzene (MCB) was evaluated for various influent volatile organic compound (VOC) loadings using coal and mixed consortium of activated sludge as the packing material. Microbial acclimation to MCB was achieved by exposing the system continuously for 31 d to an average inlet MCB concentration of 0.688 g m(-3) at an empty bed residence time (EBRT) of 188 s. The TBAB achieved maximum removal efficiency of 87% at an EBRT of 188 s for an inlet concentration of 0.681 g m(-3), which is quite significance than the values reported in the literature. Elimination capacities of MCB increased with an increase of the influent VOC loading, but an opposite trend was observed for the removal efficiency The maximum elimination capacity of the biofilter was 110.75 g m(-3) hr(-1) at an inlet MCB concentration of 1.47 g m(-3). The effect of starvation on the TBAB was also studied. After starvation, the TBAB lost its ability to degrade MCB initially However the biofilter recovered very quickly Evaluation of the concentration profile along the bed height indicated that the bottom section of TBAB has the best performance for all concentrations. By using Wani's method of macrokinetic determination based on simple Monod kinetics, the maximum removal rate of MCB, r(max) and saturation constant K(m) was to be found as 1.304 g m(-3)s(-1) and 113.446 g m(-3), respectively.  相似文献   
125.
This paper reports on the pollution profile of Damodar river sediment as obtained from analysis of the river sediment at suitable selected sites in the Raniganj-Durgapur industrial belt, West Bengal, India. The parameters measured include (a) silica, mixed oxide, calcium, magnesium, total water-soluble exchangeable cation and anion, chemical oxygen demand, and (b) some toxic and other elements, such as sodium, potassium, arsenic, cadmium, chromium, mercury, manganese, lead, zinc, cobalt, copper, iron nickel, phosphorus, sulphur, and vanadium. The parameters listed under (a) led to the characterization of the sediment, and those under (b) gave an index of metal pollution of the sediment. The elements were estimated by inductively coupled plasma emission spectrometry.  相似文献   
126.

Mining of minerals exerts adverse pressure on different compartments of environment directly or indirectly. Air is the worst affected environmental matrix, and it can carry the harmful effect of pollutants generated from mining activity even to distant places. The present study was undertaken to estimate the emission of particulate matter (PM2.5 and PM10) from different activities undertaken in stone quarrying in Mahendragarh, Haryana. The results obtained from the present study indicated that drilling, blasting, crushing, and transport of mined material are chiefly responsible for the generation of dust. Whereas drilling, blasting, and loading were responsible for emission of higher fraction of PM10, crushing and re-suspension of roadside dust from movement of vehicles resulted in generation of relatively higher fraction of finer dust (PM2.5). Modelling the transport of dust over the Hybrid Single-Particle Lagrangian Integrated Trajectory model revealed that the emitted particle may move up to the distance of about 40 km within 4 h of emission under average meteorological conditions. Fourier transform infrared (FTIR) spectroscopy analysis of dust confirmed the presence of calcite and gypsum, thus confirming the source as mining. The study concluded that generation of PM2.5-sized particles may impose serious respiratory health effects over the workers engaged in mining, crushing, and transportation of sandstone. Apart from it, population residing downwind of the mining area is particularly vulnerable to the pulmonary effects due to inhalation of dust.

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127.
Journal of Material Cycles and Waste Management - In this study, an effort has been made to use concrete waste debris for the manufacturing of fly ash bricks as a sustainable material. Though in...  相似文献   
128.
This paper presents models for predicting estimates of maximum weights of lift acceptable to industrial workers for 8-hour work shifts. Prediction models are also presented for heart rate and oxygen uptake at the maximum acceptable weight of lift. Experimental data collected on 37 males and 37 females were used in developing and verifying these models. Each subject performed nine variations of a lifting task involving three heights, four frequencies, and three box sizes to determine estimates of acceptable lifts for 8-hour shifts. The final lifting capability prediction models explained 76 to 82% variance in the experimental data. A procedure is also described to determine, from these models, acceptable lifts for work periods of variable lengths. The physiological-response-prediction models, which provide estimates of heart rate and oxygen uptake at the maximum acceptable weight of lift, were, however, relatively inferior to other similar response models available in the literature. This is thought to be due to the differences between the psychophysical and physiological methodologies.  相似文献   
129.
Environment Systems and Decisions - Capacity building and monitoring of response capacity are critical to disaster preparedness. Assessing disaster response capacity is a challenging task in India...  相似文献   
130.
Environmental Science and Pollution Research - Exposure to lead among children, as well as adults, is a major global health issue. With diverse routes of exposure (e.g., food, air, and water)...  相似文献   
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