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Oxidative stress is involved in the activation of NF-κB signal pathway and immune inflammatory response in grass carp gill induced by cypermethrin and/or sulfamethoxazole Full text
2022
Li, Baoying | Wang, Yu | Zhao, Hongjing | Yin, Kai | Liu, Yachen | Wang, Dongxu | Zong, Hui | Xing, Mingwei
At present, the concentration of environmental pollutants, such as pesticides and antibiotics exposed in environment, especially in aquatic environment is increasing. Research on environmental pollutants has exploded in the last few years. However, studies on the combined effects of pesticides and antibiotics on fish are rare, especially the toxic damage to gill tissue is vague. In this paper, cypermethrin (CMN) and sulfamethoxazole (SMZ) were analyzed and found that there was a strong correlation between the pathways affected by the first 30 genes regulated by CMN and SMZ, respectively. Therefore, the toxic effects of CMN (0.651 μg L⁻¹) and/or SMZ (0.3 μg L⁻¹) on grass carp gill were studied in this paper. Histopathology, quantitative real-time PCR, and other methods were used to detect the tissue morphology, oxidative stress level, inflammation, and apoptosis-related indicators of the fish gills after exposure of 42 days. It was found that compared with the single exposure (CMN/SMZ) group, the combined exposure (MIX) group had a more pronounced oxidative stress index imbalance. At the same time, nuclear factor-κB (NF-κB) signal pathway was activated and immuno-inflammatory reaction appeared in MIX group. The expression of tumor necrosis factor (TNF-α) in the rising range is 2.94 times that of the C group, while the expression of interleukin 8 (IL-8) is as high as 32.67 times. This study reveals the harm of CMN and SMZ to fish, and provides a reference and basis for the rational use of pesticides and antibiotics.
Show more [+] Less [-]Electron beam induced degradation of indomethacin in aqueous solution: kinetics, degradation mechanism, and toxicity assessment Full text
2022
Duan, Yu | Zhou, Wei | Shao, Haiyang | Zhang, Zhibo | Shi, Wenyan | Xu, Gang
Pharmaceutical compounds were emerging contaminants, and the accumulation of pharmaceutical compounds in the environment increased the risk to humans and ecosystems. In this study, electron beam irradiation was applied to degrade indomethacin (IDM) in aqueous solution. IDM degradation followed pseudo-first-order kinetics and 300 μM IDM could be completely degraded at only 2 kGy. According to the quenching experiment, the dose constant ratios of oxidative radicals (•OH) and reductive radicals (e⁻aq and •H) could be calculated as k•OH: kₑₐq ₐₙd •H=4.79:1. As the concentration of H₂O₂ increased from 0 to 10 mM, the dose constant increased from 1.883 to 2.582 kGy⁻¹. However, degradation effect would be restrained in the existence of NO⁻₃, NO⁻₂, CO²⁻₃, HCO⁻₃, SO²⁻, and humic acid due to their competition for the active species. Theoretical calculation revealed the radical attacking sites of IDM molecule and the most probable pathways were proposed with identification of intermediates. The attack of •OH mainly resulted in the cleavage of amide bond, indole ring opening, demethoxylation, and •OH addition. Dechlorination and the reduction of the carbonyl group occurred on IDM molecular through the reduction of e⁻ₐq and •H. The intermediates could continue to be degraded to small molecule acid, such as formic acid, acetic acid, and oxalic acid. Furthermore, highly toxic IDM transformed into less toxic products during the irradiation process.
Show more [+] Less [-]Preferential removal of benzene, toluene, ethylbenzene, and xylene (BTEX) by persulfate in ethanol-containing aquifer materials Full text
2022
Wang, Huan | Chen, Yudao | Meng, Wei | Jiang, Yaping | Cheng, Yaping
The effective approaches to eliminate impacts of ethanol on the biodegradation of benzene, toluene, ethylbenzene, and xylene (BTEX) are concerned in the bioremediation of groundwater contaminated with ethanol-blended gasoline. In situ chemical oxidation (ISCO) is a common technique widely used for the remediation of contaminated groundwater. However, the selectivity of ISCO for BTEX and ethanol removal is poorly understood. Therefore, a batch experiment was performed with different aquifer materials, including calcareous soil, basalt soil, granite soil, dolomite, and sand. Gasoline was used to provide dissolved BTEX and ethanol reagent was used as additive to improve the quality of gasoline and to reduce the possibility of air pollution caused by gasoline. Persulfate (PS) was used as a chemical oxidant to oxidize organic contaminants. The target concentrations of BTEX and ethanol were 20 mg/L and 1000 mg/L, respectively. The results showed that ethanol could be preferentially degraded in the absence of PS and inhibit BTEX biodegradation. However, BTEX could be preferentially removed prior to ethanol in all aquifer materials used at ambient temperature, when PS was added at a PS/BTEX molar ratio of 150. Over 94% BTEX in sand, dolomite, and granite soil was preferentially removed with the first-order decay rate constants of 0.890–2.703 day⁻¹ within the first ~ 10 days, followed by calcareous and basalt soil at the constants of 0.123–0.371 day⁻¹. Ethanol could compete with BTEX for sulfate radical at the first-order decay rate constants of 0.005–0.060 day⁻¹ for the first 25 days, which was slower than that of BTEX. The pH quickly decreased to < 2.5 in dolomite, sand, and granite soil, but maintained > 6.2 in calcareous soil. Rich organic matter in calcareous and basalt soil had an inhibition effect on BTEX oxidation by PS. The pH buffer in calcareous soil may imply the potential of PS oxidation combined with bioremediation in carbonate rock regions.
Show more [+] Less [-]Construction of cleaner production management system in China: mode innovation of cleaner production Full text
2022
Yu, Han | Zhao, Yinglun | Yang, Nan | Pan, Zhicheng | Yu, Hongbing
This study is based on the practice of cleaner production (CP) audits in more than 300 enterprises. After reviewing 1484 CP options, it is found that 82.5% of the options are directly and indirectly related to management. Moreover, there are common problems such as the poor sustainability of CP audit results. This shows that enterprise management plays a significant role in implementing CP options. Based on these, this study proposes a new concept of cleaner production management (CPM) system, and draws lessons from the modern environmental management theory and method to establish the framework of CPM system. This system combines the theory and method of CP with the management system of enterprises and presents the CPM requirements in the current enterprise management system, which mainly includes CPM responsibilities, CP objectives, CPM indexes, CP energy resources management, CP process control, CP product management, CPM inspections, and CP performance evaluation. The characteristic of the proposed system is to construct a modern information-based CPM system. With highly systematic, concise structure, and easy operability, this system not only simplifies and improves the CP work in enterprises and reduces several tedious tasks such as document preparation, but also enhance the enterprise management efficiency and motivate the willingness of employees to participate in CP. Innovated and developed for CP implementation, the system has been implemented and applied in Chinese enterprises, and the implementation and application have obvious effects on improving production level as well as environmental and economic benefits.
Show more [+] Less [-]Three kinds of active thin-layer capping materials for reducing the phosphorus load in eutrophic water body: comparison in dynamic experiment Full text
2022
Wang, Yichao | Li, Shuwen | Liu, Shupo | Li, Fei | Zhou, Zhenming
In this article, dynamic simulation experiments have studied the effects of three capping materials, quartz sand (QS), aluminum-based phosphorus-locking agent (Al-PIA), and lanthanum-modified bentonite (LMB) in reducing phosphorus load in eutrophic water bodies. The changes of various forms of phosphorus in Al-PIA and sediment before and after the test were analyzed, and the mechanism of phosphorus migration and transformation in different capping systems was described. The dynamic simulation test lasted 95 days. The results showed that when the initial concentration of total phosphorus (TP) was 3.55 mg/L, the capping strength was 2 kg/m² and the hydraulic retention time of water circulation was 0.5 days, indicating that the average reduction rates of TP by LMB, Al-PIA and QS systems were 74.66%, 69.54%, and 3.64%, respectively, compared with the control system. The analysis of variance showed that there were significant differences (P < 0.05) in the TP concentration of the overlying water between the LMB, Al-PIA capping system, and the control system. Lanthanum ions in LMB can fix phosphorus. Al-PIA reduces the phosphorus concentration in water by means of ion exchange, adsorption, complexation, etc. LMB and Al-PIA promoted the migration of phosphorus in sediment. Among them, the phosphorus fixed by Al-PIA was mainly in the form of non-apatite inorganic phosphorus (NAIP) in inorganic phosphorus (IP), which can be seen; Al-PIA can effectively reduce the phosphorus load of eutrophic water.
Show more [+] Less [-]Chemical characterization and nutritional quality investigations of healthy extra virgin olive oil flavored with chili pepper Full text
2022
Zellama, Mohamed Salem | Chahdoura, Hassiba | Zairi, Amira | Ziani, Borhane Eddine Cherif | Boujbiha, Mohamed Ali | Snoussi, Mejdi | Ismail, Sara | Flamini, Guido | Mosbah, Habib | Selmi, Boulbaba | El-Bok, Safia | Chaouachi, Maher
The production of extra virgin olive oil (EVOO) flavored with diverse spices, herbs, fruits, and vegetables or natural aromas is believed to provide advantageous properties considering either the high nutritional value or biological activity in addition to the flavoring and industrial aspects. The biological activities including antioxidant and antimicrobial properties of Tunisian EVOO obtained from “Chemlali” variety and mixed with chili pepper were investigated. Molecular analyses, including the detection of twelve olive-infecting viruses and Pseudomonas savastanoi pv savastanoi, were performed to ensure that the samples were obtained from healthy olive trees and EVOO quality was not affected. Quality parameters like free acidity, peroxide number, oxidative stability, and specific absorption at K232 nm and K270 nm were also investigated and no significant variation was revealed. The content of minor compounds such as chlorophylls, carotenoids, and total phenols showed minor changes. However, the profiles of the volatile compounds showed remarkable differences, which appeared to be the main factor for the observed variability in consumer acceptance. The results showed for the first time high quantities of polyphenols and ortho-diphenols. Four colorimetric methods were used for the determination of the antioxidant activity, namely DPPH, ABTS, FRAP, and β-carotene test. Compared to the control, a higher level of antioxidant activity was observed for the flavored EVOO. Furthermore, significant results were obtained in the antimicrobial tests. The quality parameters of the mixture showed no alteration compared to the control. Finally, all the measurements and the chemical characterization gave a scientific basis for food technology innovation of new food products.
Show more [+] Less [-]Investigating the performance of dish solar distiller with phase change material mixed with Al2O3 nanoparticles under different water depths Full text
2022
Saleh, Bahaa | Essa, Fadl Abdelmonem | Aly, Ayman | Alsehli, Mishal | Panchal, Hitesh | Afzal, Asif | Shanmugan, Sengottiyan
The problem of potable water shortage all over the world made the scientists seek for solutions to overcome this problem. Solar distiller is one of the introduced solutions, but it demerited by the low freshwater output. In this proposed paper, a design modification includes the use of a convex dish absorber instead of the flat absorber liner. The modified solar distiller is nominated by dish solar distiller. The base of dish solar distiller was circular. In addition, a cotton wick was used as a wetting material for facilitating the evaporation process inside the distiller. Besides, the effect of different water heights in the clearance around the dish dome was investigated for 1, 3, 5, 7, 9, and 12 cm. Finally, the space under the dish absorber is filled with a phase change material of paraffin wax mixed with aluminum oxide nanoparticles. Experimental results revealed that the best dish height that provided the highest freshwater productivity was 9 cm, where the average daily yields of dish solar distiller (at 9 cm) and conventional distillers were reported as 4500 and 3000 mL/m².day, respectively. Then, the productivity of dish solar distiller was improved by around 50% over that of the conventional distiller. In addition, when using the phase change material, the average daily distillate of dish solar distiller was improved by approximately 95% compared to that of the conventional solar still, where the distillate of conventional still and dish solar distiller with phase change material at 9 cm water depth was 3580 and 6980 mL/m².day, respectively. Besides, the maximum thermal efficiency of dish solar distiller was obtained when using phase change material at 9 cm water depth, where it was 62.4% compared to 30% for the conventional distiller.
Show more [+] Less [-]Carbon performance, company financial performance, financial value, and transmission channel: an analysis of South African listed companies Full text
2022
Ganda, Fortune
This article examines the influence of carbon performance on corporate financial performance and company financial value among South African listed firms for the period 2014 to 2018 using a two-step GMM panel process. The short-run findings show that carbon performance develops a positive and significant association with return on assets, firm value, and Tobin’s Q. In the long run, the relationship between carbon performance and return on assets as well as firm value is significantly negative; however, the link with Tobin’s Q remains positively significant. Where carbon performance is employed as the dependent parameter, a positive, significant relationship is established with return on assets, firm value, and Tobin’s Q in both the short and long run. The findings also demonstrate that carbon performance is a transmission channel whereby the debt-to-equity ratio, interest cover ratio, price to cash flow ratio, and current ratio improve corporate financial performance and firm value in the long run. In the short run, the regression analysis frameworks produce mixed findings on whether carbon performance is a transmission channel. Policy recommendations are made based on the findings.
Show more [+] Less [-]The Valorization of Luffa cylindrica as an Etheramine Biosorbent in Wastewater Treatment Full text
2022
Evangelista, Jessica C. S. | Rocha, Sônia Denise F.
The water reuse in mineral processing as well as the quality of hydric bodies that receive the effluents can be benefited with the removal of etheramines. In this study, synthetic effluents with etheramines (EDA) were treated by adsorption, in batch and in a fixed bed column, using Luffa cylindrica. The biosorbent was washed in three cross-current steps of 60 min. The increase in pH from 7.5 to 9.5 provided a small increase in the EDA amount adsorbed, but a subsequent rise to 10.5 slightly impacted the adsorption. At equilibrium, the adsorption capacity in TOC (total organic carbon) was 7.98 mg/g (Cᵢ = 50 mg/l) and 22.47 mg/g (Cᵢ = 200 mg/l) and the kinetics was represented by a pseudo-second-order model. Based on determination coefficients, the Freundlich, Redlich-Peterson, and Sips isotherms were similar with adequate fits. In a column of d = 13 mm and h = 25 cm, the breakthrough curves were represented by the Yan model. At pH 7.5 and 26 °C, the effects of bed height (5, 10, 15, and 20 cm), feed flow rates (3.2; 8.9; 14.5; and 22.8 ml/min), and initial EDA concentrations of 50 and 150 mg/l on adsorption were evaluated. The column tends to a fast exhaustion at higher application rates (17.177 ml/cm².min); however, there was a greater stability using a lower one (6.705 ml/cm².min). The shortest exhaustion time was 60 min for hL = 10 cm and superficial application rate of 17.177 ml/min.cm² and the longest time was 360 min for the lowest superficial application rate (2.411 ml/min.cm²). From the results, it can be inferred that the column adsorption of etheramines by Luffa cylindrica presents high potential for use in the treatment of liquid effluents containing residual concentrations of EDA.
Show more [+] Less [-]Evaluation of phoxim toxicity on aquatic and zebrafish intestinal microbiota by metagenomics and 16S rRNA gene sequencing analysis Full text
2022
Zhang, Jinfeng | Zhang, Qi | Zhang, Zhenyan | Zhou, Zhigao | Lu, Tao | Sun, Liwei | Qian, Haifeng
Phoxim is one of the main organophosphorus pesticides used in agricultural production. However, little information is known about how it affects the aquatic microbial community and the intestinal microbiota of fish. Herein, we utilized shotgun metagenomics and 16S rRNA gene sequencing to reveal the aquatic eco-risk of phoxim. Seven days of phoxim exposure significantly changed the composition of aquatic microbial community, obliterated the interactions between microorganisms, and thus reduced the complexity and stability of the microbial community. During long-time exposure (i.e., 14 days), most of the ecological functions were restored due to the redundancy of the microbial community. However, phoxim exposure promoted the dissemination of elfamycin resistance gene. The zebrafish gut microbial community also recovered from a temporary ecological disorder of aquatic microbiota, but phoxim continually affected zebrafish growth and swimming behavior. Overall, our results demonstrated that phoxim exposure significantly changed the structure and function of the microbial community and displayed a negative impact on freshwater ecosystems in a short exposure time.
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