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421.
Nootropic drugs like piracetam, oxiracetam, and nifiracetam are used as memory enhancers. They are thought to directly influence the energetic processes in the brain and produce elevated acetylcholine levels, but they lack protecting therapeutic potentials. Thus, there is a continuing effort directed towards developing a new cognition-enhancing agent, which would be more effective than the currently available drugs, and 2-Naphthyloxy derivatives (PP-20/DPJ) were consequently developed. This in vivo study was designed to compare the memory enhancing potential of PP-20/DPJ with the known nootropic agent, piracetam, in aluminum (Al)-induced neurotoxic model. Results indicated that PP-20/DPJ improved the short-term memory and cognitive behaviors similar to piracetam. Further, both the compounds were equally effective in elevating the acetylcholinesterase and Mg+-ATPase enzyme activity in both the brain regions after Al treatment. Thus the current study suggests, that PP-20/DPJ acts as both a cognition-enhancing agent and as a metabolic enhancer. 相似文献
422.
In view of the widespread use of pesticides in agriculture and its associated toxic effects on environment and human beings, the fate of these chemicals in soil is of major concern. The pesticide adsorption process is one of the major factors affecting its persistence and movement in the soil. With a view of studying the fate of malathion in soil, the adsorption of this insecticide was studied on three Indian soils by using batch equilibrium method. To carry out the adsorption study, a new simple, sensitive, and rapid method was developed, based on microwave-assisted alkaline hydrolysis of insecticide to the dimethyl dithiophosphate and its subsequent reaction with copper(I) perchlorate in acetonitrile. On mixing the reagents, a yellow color developed, which was stable for 120?min and was measured at 419?nm. The adsorption of malathion was studied by using Freundlich's adsorption equation and n f values were observed less than 1 in all the soils. The leaching behavior of the insecticide was studied in terms of ground ubiquity score, which was below 1.8, classifying malathion as non-leacher pesticide, and hence it is not hazardous. 相似文献
423.
This work deals with the use of polysaccharide-based beads for controlled release of the herbicide atrazine. This article discusses the release of the herbicide atrazine from neem-alginate-clay-based beads. Formulation characteristics such as entrapment efficiency, bead size, and diffusion mechanism for release of atrazine have been evaluated. 相似文献
424.
Increasing demand for water in domestic, agricultural, and industrial sectors necessitates exploitation of water either in the form of groundwater or from natural resources. To safeguard the long-term sustainability of water resources and their utilization, the quality of water has to be periodically monitored and determined for various characteristics, especially when the sources are polluted, such as Damodar river. Central Institute of Mining and Fuel Research (CIMFR), Dhanbad, is carrying out research work on coal and its utilization and associated environmental concerns. The blood stream of life for the whole Jharia Coalfield is none other than the river Damodar. CIMFR's campus also depends exclusively on river Damodar for meeting its demand of drinking water. This study is a general survey toward the characteristics of Damodar river water, with special emphasis on the pollutant parameters, and evaluation of the treatment process being carried out at the institute for potability. Damodar river water is indeed affected by the disposal of the wastes without any pre-treatment by different coal-based industries established in its basin. The quantity of dissolved and suspended solids, total hardness, chemical oxygen demand, and coliform bacterial count are higher in Damodar water due to the disposal of the waste/effluents from coal-washing plants, coke ovens, cement, and other industries, but well within the permissible limit which is probably attributable to the high-carrying capacity of the river. The river is still not that much affected as it is usually apprehended, and it can be well utilized for potable and domestic purposes after simple treatment. 相似文献
425.
The toxic effects of mercury are known to be complex with specific enzyme inhibitions and subsequent oxidative stress adding to the damaging effects. There are likely other factors involved, such as the development of impaired metal ion homeostasis and depletion of thiol- and selenium-based metabolites such as cysteine and selenium. Much of the toxicity of mercury occurs at the intracellular level via binding of Hg2+ to thiol groups in specific proteins. Therefore, amelioration of mercury toxicity by the use of chelation would likely be enhanced by the use of a chelator that could cross the cell membrane and the blood brain barrier. It would be most favorable if this compound was of low toxicity, had appropriate pharmacokinetics, bound and rendered mercury cation non-toxic and had antioxidant properties. Herein we report on such a chelator, N,N′-bis(2-mercaptoethyl)isophthalamide (NBMI), and, using an animal model, show that it prevented the toxic effects associated with acute exposure induced by injected mercury chloride. 相似文献
426.
The present study demonstrates elevated concentrations of air-borne heavy metals (Fe, 4.791; Cr, 3.142; Pb, 1.718; Cd, 0.069 μg·m?3) in an industrial region and their subsequent accumulation in tree species grown in that area. Lagerstomia speciosa showed the highest leaf metal concentrations, whereas the lowest metal concentration was observed in Acacia moniliformis. Air accumulation factors (AAF) for heavy metals were in the sequence Cd>Cr>Pb>Fe. Plants exposed to air-borne heavy metals showed a significant (p<0.01, p<0.05) decrease in total chlorophyll and soluble sugars content, with higher synthesis of cellular antioxidants compared with ascorbic acids, proline and thiols (NP-SH). Plants with higher air-borne metal accumulation factors (AAF) generally have a high air pollution tolerance index (APTI) value. Assessment of the anticipated performance index (API) gave Alstonia scholaris as the ‘best variety’ and A. moniliformis and Shorea robusta as ‘very good’ for plantation and greenbelt development in an industrial region. 相似文献
427.
Srivastava Pratiksha Gupta Supriya Garaniya Vikram Abbassi Rouzbeh Yadav Asheesh Kumar 《Environmental Chemistry Letters》2019,17(2):1045-1051
Environmental Chemistry Letters - Microbial fuel cells are used as an alternative source of energy and for microbial degradation of waste and pollutants. Different types of microbial fuel cells... 相似文献
428.
Gupta N Sharma RC Tripathi AK 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(3):381-386
Aquatic biodiversity is one of the most essential characteristics of the aquatic ecosystem formaintaining its stability and a means of coping with any environmental change. The entire stretch of the Mothronwala swamp has rich riparian vegetation for providing conducive environment for the growth of aquatic organisms. The present work has been undertaken to study the bio-physico-chemical characteristics of the swamp. The data on physico-chemical environmental variables (temperature, total dissolved solutes, size and composition of substratum, pH, dissolved oxygen, alkalinity chlorides, and hardness) have been given under the present contribution. A total of 16 genera of aquatic insects belonging to orders Trichoptera, Coleoptera, Hemiptera, Ephemeroptera, Odonata and Phylum Mollusca represented the macroinvertebrates of Mothronwala swamp. The fresh water swamp of Mothronwala is under threat due to human interference and other anthropogenic activities. Some of the natural and anthropogenic environmental problems of the Mothronwala swamp have been identified and the ameliorative measures for the protection of aquatic environment and the conservation measures for the swamp have been suggested. The qualitative study revealed the present status of the aquatic biodiversity of the swamp and also about the physico-chemical parameters, which would be very helpful for policy makers to take precautionary measures to save the swamp. 相似文献
429.
Effect of carbon and nitrogen source amendment on synthetic dyes decolourizing efficiency of white-rot fungus, Phanerochaete chrysosporium 总被引:2,自引:0,他引:2
Pant D Singh A Satyawali Y Gupta RK 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(1):79-84
Decolourization activity of Phanerochaete chrysosporium for three synthetic dyes viz., congo red, malachite green and crystal violet and impact of additional carbon and nitrogen supply on decolourization capacity of fungus were investigated. Maximum decolourizing capacity was observed up to 15 ppm. Addition of urea as nitrogen source and glucose as carbon source significantly enhanced decolourizing capacity (up to 87%) of fungus. In all the cases, both colour and COD were reduced more in non-sterilized treatments as compared to sterilized ones. Significant reductions in COD content of dye solutions (79-84%) were recorded by fungus supplied with additional carbon and nitrogen. A highly significant correlation (r = 0.78, p < 0.001) between colour and COD of dye solutions was recorded. Thus, a readily available carbon and nitrogen source is imperative to enhance the bioremediation activity of this fungus which has been the most suitable for synthetic dyes and textile industry wastewater treatment. 相似文献
430.
Mercury induced architectural alterations in the gill surface of a fresh water fish,Channa punctatus
Gupta N Dua A 《Journal of environmental biology / Academy of Environmental Biology, India》2002,23(4):383-386
An air-breathing fresh waterfish Channa punctatus was exposed chronically to sublethal concentrations of mercuric chloride and the respiratory surface was found to exhibit lesions, lifting of lamellar epithelium and increased number of mucus gland openings. The damage increased with increase in the concentrations. The gill surface was studied using scanning electron microscope. 相似文献