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Effect of transport infrastructure development on selected components of the environment of inner-city river valley and the possibility of its revitalization (Lublin, Poland) Texte intégral
2022
Zubala, Tomasz
The study covered an urban river valley, strongly transformed due to the transport infrastructure development. The paper evaluates changes in spatial management of the valley section passing through the city centre that occurred during the past two centuries (long-term and short-term phenomena) as well as their effect on selected environmental components. The basic spatial analyses were carried out with the use of specialized software, cartographic materials and photographic and descriptive documentation of the studied area (archival data). The most unfavourable changes in the potential of the valley environment occurred over the past few decades. They are manifested in a considerable deterioration of landscape values as well as the quantity and quality of water resources. Relationship was identified between water quality and intensity of motor vehicle traffic near the river. Despite the progressing urbanisation of the valley, revitalisation procedures can be still carried out and attractive space in the city centre can be created. In order to demonstrate the reasonableness of the presented concept, the paper suggests that urban succession should be incorporated as a term covering time trends and accumulated transformations. It can be helpful in analysing and determining the directions of development in disputable situations.
Afficher plus [+] Moins [-]Long-term exposure of the binary mixture of cadmium and mercury damages the developed ovary of adult zebrafish Texte intégral
2022
Patel, Utsav N. | Patel, Urvesh D. | Khadayata, Aniket V. | Vaja, Rahul K. | Modi, Chirag M. | Patel, Harshad B.
The toxicity of the binary mixture of cadmium (Cd) and mercury (Hg) on the ovary of adult zebrafish was evaluated in the present study. Adult female zebrafish were exposed to cadmium chloride (1 mg/L), mercury chloride (30 µg/L), and a binary mixture of both metals for 21 days. The toxic effects of both metals on the ovary were investigated by evaluating the oxidative stress markers and related gene expression in ovarian tissue along with the histopathological examination. The significantly decreased level of GSH and increased level of MDA in ovarian tissue of adult female zebrafish exposed to Cd + Hg indicated that the exposure of binary mixture of Cd and Hg caused more lipid peroxidation in the ovary. The significant changes in expression of mRNA of catalase (CAT) and nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2) were not observed in the ovary of zebrafish exposed to the binary mixture. Upon histological evaluation, a decreased number of full-growth (mature) oocytes along with degenerative changes due to Cd exposure were noticed, while ovary of zebrafish of the Hg-exposed group had shown a decreased number of pre-and early vitellogenic oocytes along with atretic previtellogenic oocytes compared to the control group. The ovary of zebrafish of the Cd + Hg-exposed group had shown a decreased number of previtellogenic oocytes with marked pathological changes in mature oocytes. Present findings elucidate that simultaneous long-term exposure of Cd and Hg compared to individual exposure significantly damaged the various stages of oocytes of an ovary of adult zebrafish.
Afficher plus [+] Moins [-]Performance evaluation of ceramic membrane bioreactor: effect of operational parameters on micropollutant removal and membrane fouling Texte intégral
2022
Caglak, Abdulkadir | Chormey, Dotse Selali | Bakirdere, Sezgin | Onkal Engin, Guleda
This paper presents the removal of nine potential endocrine disruptors including pesticides, pharmaceuticals and industrial chemicals using a submerged membrane bioreactor (MBR) system. Two lab-scale submerged MBRs having ceramic membranes were operated at three different sludge retention times (SRT: 15, 45, 90 days) and two hydraulic retention times (HRT: 12, 6 h) and the effects of SRT and HRT on both micropollutant removal and membrane fouling were investigated. While the effect of SRT and HRT change was observed on the removal of atrazine, fluoxetine, penconazole, no significant change was detected for the other micropollutants studied. It was determined that physicochemical properties such as distribution coefficient (LogD) and hydrophobicity of micropollutants are also effective on the removal efficiency of micropollutants. High removal efficiencies ([Formula: see text] 97.5%) were observed for hydrophobic pollutants (logD > 3.2) except for penconazole (72.1%) and for hydrophilic pollutants (logD < 3.2) except for atrazine (42.5%). Membrane fouling was significantly affected by different operational parameters applied, with the slowest fouling occurring at 45 days of SRT and 12 h of HRT. However, micropollutant addition did not have a significant effect on membrane fouling. It has been shown that the simultaneous and effective treatment performance for micropollutants makes the membrane bioreactor system a promising wastewater treatment process.
Afficher plus [+] Moins [-]Regional air pollution severity affects the incidence of acute myocardial infarction triggered by short-term pollutant exposure: a time-stratified case-crossover analysis Texte intégral
2022
Yan, Zhijian | Chen, Ping-Ling
Long-term exposure to air pollution results in a high incidence of cardiovascular disease. Many studies have found that short-term exposure to air pollution can trigger acute myocardial infarction. This study aims to determine whether results in areas with different levels of severity of air pollution are similar. The study design is a time-stratified case-crossover analysis. This was a retrospective study based on hospital medical records. The study period was since 1 January 2017 to 31 December 2018. Research data were collected from Taoyuan Hospital, located in an area with low severity of pollution, and Taichung Hospital, located in an area with high severity of pollution. The correlation between short-term air pollution exposure and acute myocardial infarction was analyzed. The correlation between short-term exposure to ambient air pollutants and acute myocardial infarction was not significant for the cases collected from Taoyuan Hospital (PM₂.₅ OR: 1.006 and 95% CI: 0.995–1.017; PM₁₀ OR: 0.996 and 95% CI: 0.988–1.003). However, for the cases collected from Taichung Hospital, short-term exposure to ambient PM₂.₅ (odds ratio: 1.021; 95% confidence interval: 1.002–1.040) and PM₁₀ (odds ratio: 1.010; 95% confidence interval: 1.001–1.020) resulted in high incidence of acute myocardial infarction. Short-term pollutant exposure will increase the incidence of acute myocardial infarction based on the severity of regional air pollution. In addition to addressing traditional cardiovascular disease risk factors, the government must formulate relevant policies for reducing air pollution and the resulting hazards to citizens’ health.
Afficher plus [+] Moins [-]Application of hydrophilic modified nylon fabric membrane in an anammox-membrane bioreactor: performance and fouling characteristics Texte intégral
2022
Zhou, Mingda | Shi, Qin | Wang, Yayi
The membrane fouling is the main bottleneck hindering the wide applications of anammox-membrane bioreactor (MBR). In this study, surface-coating hydrophilic modification of the membrane using polyvinyl alcohol was applied in a granular anammox-MBR. Stable anammox performance of >77% total nitrogen removal efficiency was achieved in both original and modified MBRs, along with decreasing anammox granule size. The modified membrane exhibited superior flux performance, and the membrane foulants were reduced in the MBR operation. Specifically, the foulant formation rate (f) was 0.46 g·m⁻²·d⁻¹ for the modified membrane with 100-μm coating thickness (M₁₀₀) compared with 0.75 g·m⁻²·d⁻¹ for the original membrane (M₀). However, the fouling cycle of the modified membrane with 250-μm coating thickness (M₂₅₀) was greatly shortened (5 days compared with 19 days for M₀) and f increased to 1.25 g·m⁻²·d⁻¹. Specially, the excess adhesion of exopolysaccharides and humic substances to the hydrophilic modified membrane changed the fouling layer structure and filtration resistance distribution, ultimately causing higher filtration resistance when coating thickness increased. Notably, the flux decline contribution of the concentration polarization was only 33.3% for M₀, while it was 71.3% for M₂₅₀. Finally, it was revealed that using a modified membrane increased the biological secretion rate of polysaccharide but decreased the protein bio-production rate, leading to a high PS (polysaccharide)/PN (protein) ratio in the MBR. The fouling mechanism of the hydrophilic modified membrane applied in anammox-MBR was proposed, and we highlight that the degree of hydrophilic modification is crucial to mitigating membrane fouling.
Afficher plus [+] Moins [-]Abundance and Characteristics of Microplastics Contaminating the Surface Water of the Inner Gulf of Thailand Texte intégral
2022
Vibhatabandhu, Pathompong | Srithongouthai, Sarawut
Microplastics are pollutants with uncertain behaviors; they have mysterious impacts on marine environments. The present study is the first investigation of microplastic distribution in the surface water of the inner Gulf of Thailand. This study collected 100–200 L of surface water from 25 different sampling locations. Microplastics were visually counted and identified by Fourier-transform infrared microscopy. The results revealed that the average total abundance of microplastics (125–5000 µm) was 9.97 pieces/L (1.55 ng/L). Microplastics sized 125–300 µm were most abundant at all the sampling sites, accounting for 68% of the total microplastics. Fiber (35%) and fragment (34%) were the predominant microplastic shapes in the surface water. Polyethylene, polypropylene, and poly(ethylene propylene) accounted for the most prevalent polymer types. The present findings revealed that the inner Gulf of Thailand is moderately polluted by microplastics of different sizes, shapes, and types, which may pose a potential risk to coastal ecosystems.
Afficher plus [+] Moins [-]Adverse effect of rheumatoid arthritis on male Wistar rat’s fertility: protective role of Costus extract [Erratum: February 2022, v.29(6); p.9386-9387] Texte intégral
2022
Kamel, Samar | Tag, Hend M. | Ebeid, Hala | Khaled, Howayda E. | Almallah, Amani A | El-Naggar, Mohamed S.
Rheumatoid arthritis (RA) is a systemic autoimmune complaint. Advanced treatments resort to the traditional herbal therapy. The aim of this study is to assess the protective effect of Costus extract on the fertility of male rats with Freund’s adjuvant-induced rheumatoid arthritis. Thirty male adult Wistar rats (190–200 g) were divided into six groups. They were subdivided into three groups; group I was the control group that received distilled water, and groups II and III received two various doses of Costus extract (200 and 400 mg/kg, respectively) for 60 days. Another three groups were subjected to RA induction via Freund’s adjuvant. Rats were injected a dose of 0.1 ml of Freund’s complete adjuvant (FCA) in the planter area of the left hind paw and then subdivided into 3 groups. Group I of RA-induced rats were given distilled water. The other two groups were given orally (200 and 400 mg/kg dosage of extract, respectively) from the 2nd day of RA induction for 60 days. Sex organ relative weight, sperm concentration assay, testicular histopathology and immunohistochemistry of androgen receptors, TNF α, and BAX protein were determined. The results showed that RA caused a significant decrease in the relative weight of sex organs and sperm count, which were relatively improved by doses of Costus (200, 400 mg/kg). RA induction caused testicular degeneration which markedly enhanced with Costus treatment as shown in histopathological sections. RA caused a reduction in %IHC of androgen receptors and increased expression level of both TNF α and BAX protein. Using IHC, it was revealed that RA caused a reduction in the expression level of androgen receptors and an increase in the expression of both TNF α and BAX protein. We can conclude that Costus speciosus had a potentially valuable role in improving fertility disorders caused by RA.
Afficher plus [+] Moins [-]Do investors penalize the firms disclosing higher environmental performance? a cross cultural evidence Texte intégral
2022
Qureshi, Muhammad Azeem | Ahsan, Tanveer
Climate change discourse integrates 3Ps – people, planet, and profit. However, we do not find any empirical study that integrates 3Ps. Therefore, using a large global panel dataset from 46 countries, this study intends to fill this gap by providing empirical evidence about investors’ value proposition of corporate climate performance in different cultural environments. The results show that Hofstede’s cultural dimensions affect corporate climate performance and its market pricing. We find that in cultures with high power distance, low individualism, high masculinity, high uncertainty avoidance, high long-term orientation, and high restraint, the investors generally penalize the firms disclosing higher environmental performance. Strangely enough, corporate waste production is universally value irrelevant. Our results indicate some policy implications.
Afficher plus [+] Moins [-]Research on the electrochemistry synergied cellulase enzymes strengthens the anaerobic fermentation of cow dung Texte intégral
2022
Cai, Yingying | Li, Heng | Qu, Guangfei | Li, Junyan | Ren, Nanqi | Zou, Hongmei | Hu, Yinghui | Zeng, Jinhua
Lignocellulose degradation (LCD) was the key factor limiting the development of anaerobic fermentation (AF) by the cow dung (CD). In the research, the effects of cellulase pretreatment (CP) and microvoltage (MV) alone and combination on the gas production and LCD during the AF were investigated. The results showed that both CP and MV had an significant effect on the AF, though the synergistic reaction was more pronounced. The total biogas yield (TBY) could reach 11521 mL, and the highest methane production rate was 73% in the synergistic reactions, which was increased by 18.7% and 10.0% compared to CP and MV alone respectively. Meanwhile, the degradation rates of cellulose and lignin could be increased by 33.44% and 22.23%, respectively. The results of SEM, FT-IR and excitation emission matrix demonstrated that CP and MV played an important role in improving the fermentation efficiency. The microbial biomass change results indicated that the synergistic effect of CP and 0.8 V MV on the LCD was achieved by promoting the growth of lignocellulose-degrading bacteria. Moreover, the electricity could not only accelerate the movement of microorganisms and enzymes, but also promoted and enhanced the activity of enzymes, which provided an important reference for further development of the AF technology and the biogas industry.
Afficher plus [+] Moins [-]Do transport taxes reduce air pollution in the top 10 countries with the highest transport tax revenues? A country-specific panel data analysis Texte intégral
2022
Aydin, Mucahit | Bozatli, Oguzhan
Recently, policymakers have been developing some policies to improve environmental quality. Environmental taxes are the most important of these policies. This study examines the effects of transport taxes, economic growth, and fossil fuel energy consumption on air pollution within the Environmental Kuznets Curve (EKC) hypothesis framework. The study used data from 1994 to 2019 for the ten countries with the highest transport tax revenues. According to the results, while the EKC hypothesis is valid for Portugal and Switzerland, it is not valid for all other countries. Moreover, fossil fuel energy consumption seems to increase air pollution in all countries except the Netherlands and Switzerland. However, transport taxes increase air pollution in Brazil. Therefore, transport taxes are not effective in reducing air pollution. In this context, it was concluded that the structure of transport taxes should be improved or reformed. In addition, it has been underlined that those national decisions alone will not be sufficient to improve transport taxes or environmental taxes. Therefore, regulations to be made with international coordination will be more successful in combating environmental problems by preventing tax competition and increasing tax harmonization.
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