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Sulforaphane potentially attenuates arsenic-induced nephrotoxicity via the PI3K/Akt/Nrf2 pathway in albino Wistar rats 全文
2019
Thangapandiyan, Shanmugam | Ramesh, Mathan | Miltonprabu, Selvaraj | Hema, Tamilselvan | Jothi, Gunasekaran Bavithra | Nandhini, Venkatesan
Oxidative stress plays a significant role in the pathophysiology of numerous kidney diseases, generally mediated by reactive oxygen species (ROS). Arsenic (Ar) is known to exert its toxicity through the generation of ROS and inflammation. The current study investigates the protective effects of sulforaphane (SFN) against arsenic-induced renal damage via PI3K/Akt-mediated Nrf2 pathway signaling. Thirty-two male albino Wistar rats were randomly divided into four groups of eight animals each, designated as control, arsenic (Ar), sulforaphane plus Ar (SFN+Ar), and sulforaphane alone (SFN), with oral administration of Ar (5 mg/kg BW) and SFN (80 mg/kg BW) daily for 28 days. Ar administration significantly (P < 0.05) increased the levels of ROS, OHdG, Ar accumulation, and lipid peroxidation, and decreased levels of enzymatic and nonenzymatic antioxidants. Notably, a significant (P < 0.05) increase was observed in markers of apoptosis, DNA damage, TUNEL-positive cells, and dark staining of ICAM-1 in renal tissue with decreased PI3K/Akt/Nrf2 gene expression. The biochemical findings were supported by histopathological and electron microscopy evaluation, which showed severe renal damage in rats treated with Ar. Pretreatment with SFN significantly (P < 0.05) attenuated renal ROS, OHdG, lipid peroxidation, and DNA damage, and increased phase II antioxidants via PI3K/Akt-mediated Nrf2 activation in renal tissue. These results show that dietary supplementation with SFN protects against Ar-induced nephrotoxicity via the PI3K/Akt-mediated Nrf2 signaling pathway in the rat kidney.
显示更多 [+] 显示较少 [-]Pollutant removal performance of an integrated system that combines a baffled vertical-flow wetland and a scenic water body 全文
2019
Chai, Hongxiang | Li, Wenqian | Shao, Zhiyu | Li, Liang | He, Qiang
Stormwater treatment requires effective control measures and development of low-cost and high-efficiency technologies. An integrated system is developed by combining a baffled vertical-flow constructed wetland (BVFCW) and a scenic water body for stormwater quality control purpose. The objectives of the study are to compare the pollutant removal performance of the full-scale integrated system with four groups of wetland-to-scenic water body area ratios (WSARs) including 1/11, 2/11, 3/11, 4/11 and investigate its treatment efficiency. Results show that the system performs better in the removal of chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH₄⁺–N), nitrate-nitrogen (NO₃–N), and total phosphorus (TP) at the WSAR of 4/11 than that at 3/11 in sixteen-day operation, while it reaches the highest total nitrogen (TN) removal efficiency of 74.0% at the WSAR of 2/11 due to relatively rich carbon source and high influent TN concentration. The integrated system may prove the most effective COD removal at the WSAR of 4/11 for four-time aerobic/anaerobic alternating conditions, a longer flow path and more time to contact with substrates, although the influent COD is lower than that at 2/11 and 1/11. After sixteen-day operation, BVFCW achieved COD removal rate of 90.3%, NH₄⁺–N removal rate of 85.7%, NO₃–N removal rate of 68.6%, and TP removal rate of 52.5% at the WSAR of 4/11. At the WSAR of 1/11, effluent met the Class IV requirements in Chinese standards after one-week operation, while effluent met the Class III requirements under the rest conditions. Since effluent in all WSARs met the standards, WSARs of 1/11 and 2/11 were recommended.
显示更多 [+] 显示较少 [-]The occurrence of THMs and AOX in drinking water of Shandong Province, China 全文
2019
Yao, Zhenxing | Sun, Shaohua | Wang, Mingquan | Zhao, Qinghua | Jia, Ruibao
Trihalomethanes (THMs) and adsorbable organic halides (AOX) were generated in chlorinated water. The purpose of the study was to provide a comprehensive picture of concentration distribution, the seasonal and different water source variability of THMs and AOX. Data for THMs, AOX, and other physico-chemical parameters were from 538 samples of 16 drinking water work through a 3-year sampling program which was conducted in Shandong province with typical temperate and monsoonal climate. Selected samples were considered with the influence of factors such as season, water source, and disinfectant. The THMs and AOX concentration of the samples disinfected with chlorine ranged from 2.1–105 μg/L and 11–238 μg/L, respectively. The THMs and AOX concentration of the samples disinfected chlorine dioxide ranged from N.D.–47.6 μg/L and N.D.–102 μg/L, respectively. The median concentration of THMs and AOX of samples disinfected with chlorine were 35 μg/L and 61 μg/L, much higher than chlorine dioxide, respectively. Ninety-two percent of the samples disinfected with chlorine and all samples disinfected with chlorine dioxide met Chinese drinking water standard for THMs. The ratio of tribromethane (TBM) to THMs of samples disinfected with chlorine was 19%, lower than chlorine dioxide 42%. Bromine substitution factor (BSF) of THMs and initial concentration of bromide showed weak correlation, and the Spearman correlation coefficient was 0.38. THMs and AOX concentrations showed noticeable seasonal variations with the highest median concentrations in spring. The levels of THMs and AOX in drinking water varied with different water sources and followed the order local reservoir > Yellow River reservoir > ground water. The survey results complement the database of THMs and AOX occurrence in drinking water in China, and offer a significant reference data for setting disinfections by-products occurrence in countries or regions with similar climate around the world.
显示更多 [+] 显示较少 [-]Efficient removal of gaseous formaldehyde by amine-modified diatomite: a combined experimental and density functional theory study 全文
2019
Liu, Yangyu | Jia, Hongwei | Li, Chunquan | Sun, Zhiming | Pan, Yongtai | Zheng, Shuilin
Amine-modified diatomite with remarkable formaldehyde (HCHO) removal efficiency was prepared by grafting 3-aminopropyltrimethoxysilane (APTMS) in this research. The interfacial properties and microstructures of the prepared adsorbents were characterized and analyzed. The HCHO adsorption properties of the amine modified diatomite were also systematically studied, and it has been proven to be effective adsorbent with better adsorption performance than activated carbon for the removal of gaseous HCHO. Furthermore, to better explain the experimental results, we performed density functional theory (DFT) study on the adsorption system and calculated the geometry, energy, and charge parameters based on first principles. Also, the underlying adsorption mechanism was proposed detailedly by combining experimentation with DFT calculation, suggesting that amine modified diatomite can be efficient adsorbent for the elimination of gaseous formaldehyde.
显示更多 [+] 显示较少 [-]The Air Quality Health Index and all emergency department visits 全文
2019
Szyszkowicz, Mieczysław
Through a variety of media formats, the Air Quality Health Index (AQHI) has served as a valuable communication tool for the general Canadian population for several years. This index, calculated and communicated to the public on an hourly basis, is designed to provide important information on the impact of air quality on health. This presentation outlines the association between AQHI values and, for the first time, all-cause emergency department (ED) visits (over one million diagnosed ED visits). It is assumed that a higher AQHI value, reflecting increased health risk, will encourage people to take steps to reduce their exposure, by limiting the duration and intensity of outdoor activity. The case-crossover methodology was used to assess the associations between the considered exposure and ED visits. The results, the estimated odds ratios, are presented as non-linear concentration-response functions. We argue that air health effects, measured as the total number of all-cause ED visits, are related to the values of the AQHI. We postulate that there are differences in this association between males and females, possibly due to gender-specific behavior and/or health conditions.
显示更多 [+] 显示较少 [-]Influence of chlorothalonil and carbendazim fungicides on the transformation processes of urea nitrogen and related microbial populations in soil 全文
2019
Ding, Hong | Zheng, Xiangzhou | Zhang, Jin | Zhang, Yushu | Yu, Juhua | Chen, Deli
To improve crop yielding, a large amount of fungicides is continuously applied during the agricultural management, while the effects of fungicides residues on microbial processing of N in soil need further study. In the present study, two broad spectrum fungicides, chlorothalonil and carbendazim, were applied at the rates of 5, 10, and 50 mg of active ingredient (A.I.) per kg of dry soil combined with urea with 200 mg of N per kg of dry soil under laboratory conditions. The results showed that chlorothalonil obviously retarded the hydrolysis of urea, whereas carbendazim accelerated it in 4 days after the treatments (P < 0.05). Chlorothalonil reduced denitrification, nitrification, and N₂O production (P < 0.05), but not for carbendazim. Further analysis on N-associated microbial communities showed chlorothalonil reduced nitrosomonas populations at the rates of 10 and 50 mg of A.I. per kg and autotrophic nitrifying bacterial populations at three application rates (P < 0.05), but Carbendazim decreased nitrosomonas populations only at the rate of 50 mg of A.I. per kg and also autotrophic nitrifying bacterial populations at three rates and heterotrophic nitrifying bacterial populations at the rates of 10 and 50 mg of A.I. per kg. The reasons for this difference were ascribed to arrest urea hydrolysis and impediment of denitrification and nitrification processes by chlorothalonil. In conclusion, to improve crop yielding, chlorothalonil might be more beneficial to conserve soil N by improving soil N fertility, compared with carbendazim.
显示更多 [+] 显示较少 [-]Study of the effects of zinc pyrithione in biochemical parameters of the Polychaeta Hediste diversicolor: evidences of neurotoxicity at ecologically relevant concentrations 全文
2019
Nunes, Bruno | Costa, Mari
Study of the effects of zinc pyrithione in biochemical parameters of the Polychaeta Hediste diversicolor: evidences of neurotoxicity at ecologically relevant concentrations 全文
2019
Nunes, Bruno | Costa, Mari
Nowadays there are various groups of biocidal chemical agents, which can be used in diverse areas, such as personal hygiene, disinfection, antiparasitic action, and also in antifouling mixtures or paints. The versatility and efficacy of some of these agents favors their use and ultimate release into the aquatic environment, where they may still exert toxic activity. Zinc pyrithione is classified as a metal biocide with bactericidal, algicidal, and fungicidal actions. It has been formulated in antifouling paints, which prevent the formation of biofilms in submerged structures, and has also been used for dermocosmetic purposes, in shampoos for the treatment of dandruff and seborrhea. Some of the uses of zinc pyrithione are responsible for its direct release as flakes that reach the bottom sediments, especially in estuarine areas. Considering this fate, the ecotoxicity assessment of its effects towards sediment organisms, namely Polychaetous species, is extremely important. The present study characterized the acute potential toxicity of zinc pyrithione in terms of parameters of oxidative stress (catalase, glutathione S-transferases (GSTs), and thiobarbituric acid reactive substances (TBARS)), and neurotoxicity (acetylcholinesterase) which were evaluated in individuals of the polychaete Hediste diversicolor. Regarding the results obtained, only the activity of GSTs and AChE was significantly altered in relation to non-exposed animals. This set of results indicates that oxidative stress did not occur.
显示更多 [+] 显示较少 [-]Study of the effects of zinc pyrithione in biochemical parameters of the Polychaeta Hediste diversicolor: evidences of neurotoxicity at ecologically relevant concentrations 全文
2019
Nunes, Bruno | Costa, Mariana
Nowadays there are various groups of biocidal chemical agents, which can be used in diverse areas, such as personal hygiene, disinfection, antiparasitic action, and also in antifouling mixtures or paints. The versatility and efficacy of some of these agents favors their use and ultimate release into the aquatic environment, where they may still exert toxic activity. Zinc pyrithione is classified as a metal biocide with bactericidal, algicidal, and fungicidal actions. It has been formulated in antifouling paints, which prevent the formation of biofilms in submerged structures, and has also been used for dermocosmetic purposes, in shampoos for the treatment of dandruff and seborrhea. Some of the uses of zinc pyrithione are responsible for its direct release as flakes that reach the bottom sediments, especially in estuarine areas. Considering this fate, the ecotoxicity assessment of its effects towards sediment organisms, namely Polychaetous species, is extremely important. The present study characterized the acute potential toxicity of zinc pyrithione in terms of parameters of oxidative stress (catalase, glutathione S-transferases (GSTs), and thiobarbituric acid reactive substances (TBARS)), and neurotoxicity (acetylcholinesterase) which were evaluated in individuals of the polychaete Hediste diversicolor. Regarding the results obtained, only the activity of GSTs and AChE was significantly altered in relation to non-exposed animals. This set of results indicates that oxidative stress did not occur. | published
显示更多 [+] 显示较少 [-]Climate co-benefits of alternate strategies for tourist transportation: The case of Murree Hills in Pakistan 全文
2019
Shah, Izhar Hussain | Dawood, Usama Fida | Jalil, Umaima Abdul | Adnan, Yasir
This study explores the climate impacts of on-road tourist transportation with alternate mitigation strategies. To this end, greenhouse gas (GHG) emissions for 2016 and emissions under four “what-if” scenarios were estimated for a popular tourist site in Pakistan, i.e., Murree Hills, using the international vehicle emissions model. Alternate scenarios included occupancy optimization, bus transit system, and Euro II and Euro IV implementation. The emissions were further decomposed using the log mean Divisia index method to study the drivers of global warming potential (GWP) mitigation. As per the results, the total 20-year GWP for 2016 was equal to 51,262 tons CO₂ equivalent, and maximum reduction was achieved under the bus transit system scenario having a 20-year GWP of 25,736 tons CO₂ equivalent, i.e., 49.8% reduction. Relative to the base year, GWP reductions were also quite significant for Euro IV (46.8%), Euro II (45.8%), and occupancy optimization (32.3%) scenarios. For the base year, CO₂ held a share of 87.3% in total emissions; however, its share in the 20-year GWP was 39.7% indicating its reduced impact on total GWP as compared to N₂O, CO, NOx, VOC, and CH₄. Based on the decomposition results for alternate scenarios, GWP mitigation was mainly driven by CO, CH₄, NOx, VOCs, and partially by CO₂, while N₂O negatively affected GWP mitigation. These results provide several policy-level instruments for developing countries to design a transition to an eco-friendly tourist transport management system. The policy implications from this study can be used to promote an eco-tourism industry.
显示更多 [+] 显示较少 [-]Effect of energy consumption and economic growth on carbon dioxide emissions in Pakistan with dynamic ARDL simulations approach 全文
2019
Khan, Muhammad Kamran | Teng, Jian-Zhou | K̲h̲ān̲, Muḥammad ʻImrān
Environmental degradations are mainly caused by the use of different energy resources for economic growth. This research examined the influence of energy consumption (coal consumption, oil consumption, and gas consumption) and economic growth on environmental degradation in Pakistan. This research used newly developed method dynamic ARDL simulations to scrutinize the actual influence of positive and negative change in the use of coal consumption, oil consumption, and gas consumption for energy and economic growth on environmental degradation in Pakistan. The examined results of dynamic ARDL indicate that economic growth, coal consumption, oil consumption, and natural gas consumption have positive impact on the environmental degradations in Pakistan both in short run and long run. It is suggested that environmental degradations can be reduced by promoting renewable energy sources for energy.
显示更多 [+] 显示较少 [-]Distribution and potential ecological risk assessment of trace elements in the stream water and sediments from Lanmuchang area, southwest Guizhou, China 全文
2019
Rasool, Atta | Xiao, Tangfu
Trace elements contamination in sediment is regarded as the global crisis with a large share in developing countries like China. Water and sediment samples were collected during (2016) from Qingshui Stream and analyzed for major physicochemical properties and trace elements by using ICP-MS. Our result of sediments showed that studied trace elements (except Pb, Cd, Co) had a concentration higher than Chinese sediment guideline as well as stream water data for studied trace elements (except Cr, Pb, Cd, Cu, and Zn) had a higher concentration than the maximum permissible safe limit of WHO. Contamination factor (CF) confirmed a moderate to high contamination in the sediment samples due to As and Tl, respectively. The values of pollution load index (PLI) were found above one (> 1), describing the progressive sediment quality decline. Pearson correlation showed that there was a significant positive association between Tl and As (r = 0.725, p < 0.05) in sediment samples. Results revealed that water-rock interaction, weathering of Tl sulfide mineralization, and hydrogeological conditions were major sources of stream water and sediments contamination in the study area. This experimental study contributes to a better understanding of the geochemistry and prevention of trace element contamination in sediments from Lanmuchang area.
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