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101.
Environmental Science and Pollution Research - Recent advancements and growing attention about free radicals (ROS) and redox signaling enable the scientific fraternity to consider their involvement...  相似文献   
102.
Large-scale industrialization, population inflow, and rapid urbanization coupled with unfavorable meteorological conditions often induce significant degradation of urban environment. In order to assess the extent of environmental impacts due to establishment of the Integrated Industrial Estate??Pantnagar (IIE-Pantnagar), ambient air and groundwater were monitored from June 2007 to May 2008. Collected baseline information was normalized and interpreted with the application of air (AQI) and water quality indices (WQI). Among the pre-identified air pollutants, suspended particulate matter was found to be the principal culprit to deteriorate ambient air quality, with a maximum annual concentration of 418.5 ??g/m3. Monthly average concentrations of respirable particulate matter (aerodynamic diameter < 10 ??m) also persist at a critical level with an annual maximum of 207.3 ??g/m3. A segmented linear function with maximum operator concept was used to compute AQI, and the developed index was found well suitable to demonstrate temporal variations of ambient air quality. The computed AQI value for the selected study region varied from moderate (97.0) to very poor pollution level (309.2) in respect to developed air quality standards. Furthermore, an integrated WQI was developed comprising 9 parameters, and among all the 10 pre-identified locations, the average groundwater quality was found acceptable in terms of Indian drinking water standards. The maximum WQI (70.6) was found at the Kichha Railway Station during summer months, revealing moderate pollution load. Industrial discharge from IIE-Pantnagar coupled with other industrial setup may hold responsible for such kind of degradation of water quality. In contrast, WQI computed at Rudrapur City demonstrate minimum (15.0?C22.1) pollution load. For 95% of the monitoring period, the computed WQI was found acceptable for all selected locations with few exceptions. The application of WQI to assess temporal variations in groundwater quality was therefore found satisfactory.  相似文献   
103.
Our previous study suggested that toxicokinetic parameters of fluoride were significantly changed on the 30th day as compared with 1st day, after repeated oral administration of sodium fluoride alone for 30 days in goats. The purpose of this study was to investigate whether aluminum sulfate has ameliorative effect on the toxicokinetics of fluoride. For this, sodium fluoride (20 mg kg?1 b. wt.) along with aluminum sulfate (150 mg kg?1 b. wt.) was administered in goats for 30 days to investigate its effect on toxicokinetics of fluoride on days 1 and 30. The fluoride levels against time were adequately described by one compartment open model. The peak plasma level of fluoride was observed at 2 h. The toxicokinetics data revealed a nonsignificant decrease in β (elimination rate constant) and C max (the maximum plasma concentration) and increase in t 1/2 K a (absorption half-lives), t 1/2 β (elimination half-lives), area under the plasma (AUC) concentration versus time curve and mean residence time (MRT) was observed for the last dose from their respective first dose values. On the basis of changes in the toxicokinetic parameters, it was concluded that repeated oral administration has cumulative effect on plasma fluoride level and concurrent oral administration of aluminum sulfate has ameliorative action on the toxicokinetics of fluoride in goats.  相似文献   
104.
This work was undertaken to ascertain the impact of different fluence rates of ultraviolet-B (UV-B) radiation on two cyanobacterial biofertilizers, Phormidium foveolarum and Nostoc muscorum, growing under copper toxicity. Copper (2 and 5?µmol?L?1) and high UV-B fluence rate (UV-BH; 1.0?µmol?m?2?s?1) decreased the growth, pigment content, photosynthetic oxygen yield, phosphate uptake, and acid phosphatase activity in both the strains analyzed after 24 and 72?h of experiments, and combined exposure further enhanced the toxic effects. Respiration and alkaline phosphatase activities were stimulated appreciably. The damaging effect was shown on the order on pigments: phycocyanin?>?chlorophyll a?>?carotenoids, and on photosystems: whole chain photosynthetic reaction?>?photosystem II?>?photosystem I. Partial recovery in the photosystem II activity in the presence of artificial electron donors; diphenyl carbazide (DPC), hydroxylamine (NH2OH), and manganese chloride (MnCl2) pointed out the interruption of electron flow on the oxidation side of photosystem II. Unlike UV-BH, low UV-B fluence rate (UV-BL; 0.1?µmol?m?2?s?1), rather than causing damaging effect partially, alleviated the toxic effects of Cu. This study suggests that the cyanobacterium P. foveolarum is less sensitive against UV-BH and excess Cu (2 and 5?µmol?L?1), thus P. foveolarum may be used as a biofertilizer for sustainable agriculture.  相似文献   
105.
This article reports the synthesis of an efficient, low-cost material from maize powder to depollute arsenic-contaminated water. Arsenic is toxic for humans and other organisms even at low concentrations. The most well-known and severe case of arsenic poisoning through drinking water has been found in India and Bangladesh. Numerous inorganic materials have been tested for the removal of arsenic from water bodies over the last two decades. However, all such materials have several disadvantages such as unpredictable arsenic ion removal, high cost and the generation of toxic sludge that is often more difficult to manage. Alternatively, organic material from agricultural waste may be modified to enrich functional groups responsible for As sorption and, in turn, used to depollute contaminated waters. Here, Zea mays cob powder has been modified to remove arsenic species from water. Two modified materials were produced: an aminated maize powder and a thiolated maize powder. Amination was done using epichlorohydrin and dimethylamine. Thiolation was done using thioglycolic acids. Amination increased As (III) sorption from 70 to 75.8 % and As (V) sorption from 85 to 94.42 %, compared with unmodified maize powder. Thiolation increased As (III) sorption from 70 to 81.7 % and As (V) sorption from 85 to 90 %. Amination increased usability cycles from 3 to 5. Thiolation increased usability cycles from 3 to 6. The novel modified maize biosorbent has enough potential for the development of a low-cost technological pre-treatment step, prior to high-tech chemical treatments.  相似文献   
106.
Environment Systems and Decisions - Organizational and technical approaches have proven successful in increasing the performance and preventing risks at socio-technical systems at all scales....  相似文献   
107.
Ladybirds (Coleoptera: Coccinellidae) provide services that are critical to food production, and they fulfill an ecological role as a food source for predators. The richness, abundance, and distribution of ladybirds, however, are compromised by many anthropogenic threats. Meanwhile, a lack of knowledge of the conservation status of most species and the factors driving their population dynamics hinders the development and implementation of conservation strategies for ladybirds. We conducted a review of the literature on the ecology, diversity, and conservation of ladybirds to identify their key ecological threats. Ladybird populations are most affected by climate factors, landscape composition, and biological invasions. We suggest mitigating actions for ladybird conservation and recovery. Short-term actions include citizen science programs and education, protective measures for habitat recovery and threatened species, prevention of the introduction of non-native species, and the maintenance and restoration of natural areas and landscape heterogeneity. Mid-term actions involve the analysis of data from monitoring programs and insect collections to disentangle the effect of different threats to ladybird populations, understand habitat use by taxa on which there is limited knowledge, and quantify temporal trends of abundance, diversity, and biomass along a management-intensity gradient. Long-term actions include the development of a worldwide monitoring program based on standardized sampling to fill data gaps, increase explanatory power, streamline analyses, and facilitate global collaborations.  相似文献   
108.
A Visual Basic simulation software (WATTPPA) has been developed to analyse the performance of an advanced wastewater treatment plant. This user-friendly and menu-driven software is based on the dynamic mathematical model for an industrial wastewater treatment scheme that integrates chemical, biological and membrane-based unit operations. The software-predicted results corroborate very well with the experimental findings as indicated in the overall correlation coefficient of the order of 0.99. The software permits pre-analysis and manipulation of input data, helps in optimization and exhibits performance of an integrated plant visually on a graphical platform. It allows quick performance analysis of the whole system as well as the individual units. The software first of its kind in its domain and in the well-known Microsoft Excel environment is likely to be very useful in successful design, optimization and operation of an advanced hybrid treatment plant for hazardous wastewater.  相似文献   
109.
Municipal solid wastes (MSW) are unavoidable sources of environmental pollution. Improper disposal of municipal waste results in the leaching of toxic metals and organic chemicals, which can contaminate the surface and ground water leading to serious health hazard. In this study, the toxic effects of the leachate prepared from municipal solid waste samples were examined in root meristem cells of barley (Hordeum vulgare L.) at various stages of cell cycle, i.e., G1, S, and G2. Seeds of barley were exposed to 2.5, 5, and 10 % of leachates in soil and aqueous media in 48 h at different cell cycle stages. The physicochemical data of the present study revealed that municipal solid waste leachate contains high amount of heavy metals, which significantly affected growth and physiological activities of barley. Significant inhibition in hypocotyl length, germination, and mitotic index were observed at all concentration of leachate treatment. Induction of chromosomal aberrations (CA’s) and micronuclei (MN) formation were also observed with different concentrations of leachate treatment at 7, 17, and 27 h of presoaking durations, which falls in G1, S, and G2 phase of the cell cycle, respectively. Also, exposure of leachate at S phase of the cell cycle had significant effects in barley through chromosomal aberration and micronuclei formation.  相似文献   
110.
Agra, one of the oldest cities “World Heritage site”, and Delhi, the capital city of India are both located in the border of Indo-Gangetic Plains (IGP) and heavily loaded with atmospheric aerosols due to tourist place, anthropogenic activities, and its topography, respectively. Therefore, there is need for monitoring of atmospheric aerosols to perceive the scenario and effects of particles over northern part of India. The present study was carried out at Agra (AGR) as well as Delhi (DEL) during winter period from November 2011 to February 2012 of fine particulate (PM2.5: d?<?2.5 μm) as well as associated carbonaceous aerosols. PM2.5 was collected at both places using medium volume air sampler (offline measurement) and analyzed for organic carbon (OC) and elemental carbon (EC). Also, simultaneously, black carbon (BC) was measured (online) at DEL. The average mass concentration of PM2.5 was 165.42?±?119.46 μg m?3 at AGR while at DEL it was 211.67?±?41.94 μg m?3 which is ~27 % higher at DEL than AGR whereas the BC mass concentration was 10.60 μg m?3. The PM2.5 was substantially higher than the annual standard stipulated by central pollution control board and United States Environmental Protection Agency standards. The average concentrations of OC and EC were 69.96?±?34.42 and 9.53?±?7.27 μm m?3, respectively. Total carbon (TC) was 79.01?±?38.98 μg m?3 at AGR, while it was 50.11?±?11.93 (OC), 10.67?±?3.56 μg m?3 (EC), and 60.78?±?14.56 μg m?3 (TC) at DEL. The OC/EC ratio was 13.75 at (AGR) and 5.45 at (DEL). The higher OC/EC ratio at Agra indicates that the formation of secondary organic aerosol which emitted from variable primary sources. Significant correlation between PM2.5 and its carbonaceous species were observed indicating similarity in sources at both sites. The average concentrations of secondary organic carbon (SOC) and primary organic carbon (POC) at AGR were 48.16 and 26.52 μg m?3 while at DEL it was 38.78 and 27.55 μg m?3, respectively. In the case of POC, similar concentrations were observed at both places but in the case of SOC higher over AGR by 24 in comparison to DEL, it is due to the high concentration of OC over AGR. Secondary organic aerosol (SOA) was 42 % higher at AGR than DEL which confirms the formation of secondary aerosol at AGR due to rural environment with higher concentrations of coarse mode particles. The SOA contribution in PM2.5 was also estimated and was ~32 and 12 % at AGR and DEL respectively. Being high loading of fine particles along with carbonaceous aerosol, it is suggested to take necessary and immediate action in mitigation of the emission of carbonaceous aerosol in the northern part of India.  相似文献   
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