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Prediction of the impact induced by Cd in binary interactions with other divalent metals on wild-type and Cd-resistant strains of Dictyosphaerium chlorelloides Texto completo
2022
Téllez, Alondra A Cortés | Sánchez-Fortún, Sebastián | Sánchez-Fortún, Ana | García-Pérez, Martha-Estrella | Chacon-Garcia, Luis | Bartolomé, M Carmen
The metals present in freshwater have a toxic profile with bioaccumulation and are biomagnified along the aquatic food chain. The metals induce high sensitivity in most aquatic organisms, while others, such as some microalgae species, evolve towards resistance. Therefore, this research predicted through the Combination Index method the binary interaction exposed to divalent metals by inhibiting population growth in a Cd-resistant strain (DcᴿCᵈ¹⁰⁰) compared to the wild-type strain (Dc1Mʷᵗ) of Dictyosphaerium chlorelloides and evaluate the specific resistance level obtained by DcᴿCᵈ¹⁰⁰ to Cd relative to other divalent metals.The results showed that DcᴿCᵈ¹⁰⁰ presents resistance compared to Dc1Mʷᵗ in individual exposure in the order of Fe²⁺ > Ni²⁺ > Cd²⁺ > Co²⁺ > Zn²⁺ > Cu²⁺ > Hg²⁺ with 50% inhibitory concentration at 72 h of exposure (IC₅₀₍₇₂₎) values 1253, 644.4, 423, 162.7, 141.3, 35.1, and 9.9 µM, respectively. It induces cross-resistance with high antagonistic rates (Combination Index (CI); CI > > 1) in the Cd/Zn and Cd/Cu. Cd/Ni, its initial response, is antagonistic, and it ends in an additive (CI = 1). DcᴿCᵈ¹⁰⁰ showed a lower resistance in Co, and Cd/Fe resistance was reduced individually. The interaction with Hg increased its resistance ten times more than individually.This research highlights the use of the CI as a highly efficient prediction method of the binary metal interactions in wild-type and Cd-resistant strains of D. chlorelloides. It may have the potential for metal accumulation, allowing the development of new methods of bioremediation of metals in effluents, and to monitor the concentration of metals in wastewater, its relative availability, transport, and mechanisms on resistant strains of microalgae.
Mostrar más [+] Menos [-]Hybrid constructed wetlands integrated with microbial fuel cells and reactive bed filter for wastewater treatment and bioelectricity generation Texto completo
2022
Colares, Gustavo Stolzenberg | Dell’Osbel, Naira | Paranhos, Gabriele | Cerentini, Patrícia | Oliveira, Gislayne A. | Silveira, Elizandro | Rodrigues, Lúcia R. | Soares, Jocelene | Lutterbeck, Carlos A. | Rodriguez, Adriane Lawisch | Vymazal, Jan | Machado, Ênio L.
The present study aimed to develop a pilot-scale integrated system composed of anaerobic biofilter (AF), a floating treatment wetland (FTW) unit, and a vertical flow constructed wetland coupled with a microbial fuel cell (CW-MFC) and a reactive bed filter (RBF) for simultaneously decentralized urban wastewater treatment and bioelectricity generation. The first treatment stage (AF) had 1450 L and two compartments: a settler and a second one filled with plastic conduits. The two CWs (1000 L each) were vegetated with mixed plant species, the first supported in a buoyant expanded polyethylene foam and the second (CW-MFC) filled with pebbles and gravel, whereas the RBF unit was filled with P adsorbent material (light expanded clay aggregate, or LECA) and sand. In the CW-MFC units, 4 pairs of electrode chambers were placed in different spacing. First, both cathode and anode electrodes were composed of graphite sticks and monitored as open circuit. Later, the cathode electrodes were replaced by granular activated carbon (GAC) and monitored as open and closed circuits. The combined system efficiently reduced COD (> 64.65%), BOD₅ (81.95%), N-NH₃ (93.17%), TP (86.93%), turbidity (94.3%), and total coliforms (removal of three log units). Concerning bioenergy, highest voltage values were obtained with GAC electrodes, reaching up to 557 mV (open circuit) and considerably lower voltage outputs with closed circuit (23.1 mV). Maximum power densities were obtained with 20 cm (0.325 mW/m²) and 30 cm (0.251 mW/m²). Besides the electrode superficial areas, the HRT and the water level may have influenced the voltage values, impacting DO and COD concentrations in the wastewater.
Mostrar más [+] Menos [-]Effects of air pollution and green spaces on impaired lung function in children: a case-control study Texto completo
2022
Zhang, Jingwei | Wang, Yuming | Feng, Lihong | Hou, Changchun | Gu, Qing
The occurrences of impaired lung function during childhood could substantially influence the health states of the respiratory system in adults. So, the effects of air pollution and green spaces on impaired lung function in children were investigated in this study. The lung function of each student was tested every year from 2015 to 2017 and the method of case-control study was applied. 2087 students aged from 9 to 11 years old of primary schools in Tianjin were ultimately included in this study. The method of propensity score matching (PSM) was performed to minimize the confounding bias and the conditional logistic regression model was carried out to evaluate the effects of indoor and outdoor environmental risk factors on the occurrences of impaired lung function in children. For every interquartile range (IQR) increase in the mixture of six air pollutants at the lag1, lag2, and lag3 periods, the risks of getting impaired lung function were increased by 53.4%, 34.7%, and 16.9%, respectively. The protective effect of greenness at lag2 period (odds ratios (OR)) = 0.022 (95% confidence interval (CI): 0.008–0.035)) was stronger than that at lag1and lag3 periods, respectively. Separate and combined effects of most air pollutants at different lag periods exerted hazardous effects on the lung function of students. Exposure to greenness had protective effects on the lung health of children.
Mostrar más [+] Menos [-]Hydrothermal synthesis of Ag-doped ZnO/sepiolite nanostructured material for enhanced photocatalytic activity Texto completo
2022
Akkari, Marwa | Bardaoui, Afrah | Djebbi, Mohamed Amine | Amara, Abdesslem Ben Haj | Chtourou, Radhouane
This work is devoted to the development of Ag-ZnO/sepiolite photocatalysts as novel nanostructured materials by the immobilization of Ag-doped ZnO on the surface of fibrous clay. Herein, innovative Ag-ZnO/sepiolite photocatalysts were successfully prepared through a simple hydrothermal route using diverse Ag dopant concentrations (2 and 5%). Structural, morphological, and optical properties of the obtained photocatalysts were characterized by XRD, TEM, MEB, and DRS-UV–Vis spectroscopy. The results confirmed that Ag-doped ZnO nanoparticles with a diameter of 10–30 nm are homogeneously distributed on the sepiolite fibers’ surface. The silver dopant was effectively incorporated into the zinc oxide, leading to a slight distortion of the hexagonal wurtzite structure and a reduction of the bandgap energy with increased silver doping. The photocatalytic activity towards the degradation of methylene blue (MB) dye was analyzed for all the samples under UV–Vis light. Compared to ZnO alone and undoped ZnO/SEP, the Ag-ZnO/SEP5% nanostructured materials exhibited a significantly improved photocatalytic activity, with full decolorization after 4 h of UV–Vis irradiation (60 W). The photocatalysis of organic pollutants matched well with a pseudo-first-order kinetic. The enhanced photocatalytic activity was ascribed to the low bandgap energy (3 eV), the reduction of the recombination of electron hole, and the sepiolite support.
Mostrar más [+] Menos [-]Investigation of Adsorption Kinetics for Per- and Poly-fluoroalkyl substances (PFAS) Adsorption onto Powder Activated Carbon (PAC) in the Competing Systems Texto completo
2022
Son, Heejong | An, Byungryul
Batch kinetic test was performed for nine per- and polyfluoroalkyl substances (PFASs). Pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models as well as the intraparticle diffusion (ID) model were used to determine the rate constants representing K₁, K₂, and Kᵢd, respectively. They were then compared to evaluate the effect of the carbon chain length and adsorption surface area (i.e., different powder activated carbon (PAC) concentrations) on the competing conditions of nine PFAS species. The lowest and average of coefficient of determination (R²) was 0.965 and 0.992, and 0.692 and 0.898 and for nonlinear and linear PFO, respectively, implying that linear PFO included extraordinary sample point. K₁ increased by 3.6 times on average from 10 and to 100 mg/L of PAC. For nonlinear PFO, K₁ increased up to 5.9 times (from 1.63 to 9.64) and 8.3 times (from 1.11 to 9.24) with the increase of the carbon chain length and PAC concentration, respectively. PSO obtained a higher average coefficient of determination (R²) of 0.996 than PFO of 0.992 determining PSO is more suitable than PFO. K₂ was more affected than K₁ by concentration of PAC based on linear and exponential quantitative correlations for K₁ and K₂, respectively, although the behavior of K₂ was a very similar to K₁ at all condition except for 100 mg/L of PAC. The value of Kᵢd showed an opposite pattern to those of K₁ and K₂, in which the sum of Kᵢd and C decreased from 3.67, 1.73, 0.816, and 19.2 to 15.1, 12.0, and 7.89 at 10, 30, 50, and 100 mg/L of PAC concentration, respectively, indicating that the effect of the film and intraparticle diffusions on the adsorption was not significant when there is higher interaction and enough surface area because, in this case, the process rapidly reaches equilibrium.
Mostrar más [+] Menos [-]Quantitative evaluation of zinc metal in meadows and ruminants for health assessment: implications for humans Texto completo
2022
Maqsood, Ayesha | K̲h̲ān̲, Ẓafar Iqbāl | Kafīl, Aḥmad | Akhtar, Shahzad | Ashfaq, Asma | Malik, Ifra Saleem | Sultana, Razia | Nadeem, Muhammad | Alkahtani, Jawaher | Dwiningsih, Yheni | Elshikh, Mohamed S.
Heavy metal pollution in soil, forage, and animals is serious concern nowadays. Current research was conducted in Sargodha to find out the relationship of animals related to the forages and soil pollution. Three sites were selected with three different treatments; site I irrigated with ground water, site II irrigated with the canal water, and site III irrigated with the wastewater. Samples of soil, forage, and animals (blood, hair, feces) were collected from selected sites and were analyzed for metal analysis using atomic absorption spectroscopy. Results indicated that Zn in soil ranged from 24.12 to 37.39 mg/kg; forage, 31.98–44.47 mg/kg; blood of animals, 1.49–2.72 mg/L; hair of animals, 1.37–2.41 mg/kg; and feces of animals, 1.06–2.97 mg/kg. The concentration of zinc in soil and forage was less than permissible limit, but concentration in blood of animals was greater than critical limit suggesting the presence of metal. Bio-concentration factor indicated that metal was accumulated in forages growing at irrigated site. HRI concentration (2.024 mg/kg/day) suggests the accumulation of zinc in animal tissues. Pollution load index and enrichment factor were within the range.
Mostrar más [+] Menos [-]Causality analysis of CO2 emissions, foreign direct investment, gross domestic product, and energy consumption: empirical evidence from South Asian Association for Regional Cooperation (SAARC) countries Texto completo
2022
Nur Mozahid, Md | Akter, Sharmin | Hafiz Iqbal, Md
Over the period 1980–2016, this study looks into the causal relations between carbon dioxide (CO₂) emissions, energy consumption (EC), foreign direct investment (FDI), and gross domestic product (GDP) in five South Asian countries (Bangladesh, India, Nepal, Pakistan, and Sri Lanka). To achieve the research objectives, panel unit root tests, panel co-integration, autoregressive distributed lag model, and Granger causality tests are used. In the long run, GDP has a positive impact on CO₂ emissions, while squared GDP has a negative impact, confirming the framework of the environmental Kuznets curve (EKC) in Pakistan and Sri Lanka. However, in the short run along with these two countries, Bangladesh also confirms the EKC hypothesis. Among these five countries, Bangladesh and Nepal support the pollution haven hypothesis, but India, Pakistan, and Sri Lanka support the FDI halo hypothesis. The EC has a large positive impact on CO₂ emissions across five countries. In the long run, the Granger causality test confirms one-way causation from EC to CO₂ emissions and bidirectional causality of FDI and CO₂. These countries might encourage clean energy technology through FDI without jeopardizing GDP and environmental quality. The findings of the study provide a guideline for these countries to reduce CO₂ emissions, achieve a long-term green GDP, and combat global warming.
Mostrar más [+] Menos [-]How can new energy vehicles become qualified relays from the perspective of carbon neutralization? Literature review and research prospect based on the CiteSpace knowledge map Texto completo
2022
Hua, Yifei | Dong, Feng
Analyzing the feasibility of fuel vehicle transition will be conducive to the realization of the carbon neutralization goal. However, at present, there are few studies specifically aimed at the transition of fuel vehicles. Therefore, this study first analyzed the necessity for the transition of fuel vehicles and then used CiteSpace to analyze 2081 articles in the core Web of Science database in the past decade with “fuel vehicle emission reduction” as the search keyword. After clarifying the research context and development frontier of fuel vehicle emission reduction, we found that most of the literature with the research theme on this topic ends with the research of electric vehicles. Therefore, we took new energy vehicles represented by electric vehicles as the starting point to explore the realization path of carbon neutralization by analyzing the development dilemma and residents’ feedback on electric vehicles. Finally, the research review and research prospects were carried out. The study found that although the development of new energy vehicles has made obvious progress at this stage, there are still some problems in comprehensively promoting electric vehicles, such as battery power, charging facilities, and the weak willingness of consumers to accept electric vehicles. Therefore, improving the usage efficiency of new energy vehicles can more effectively force fuel vehicles and new energy vehicles to complete the relay from the perspective of market attraction. This study will provide a more scientific solution and implementation path for the transition of fuel vehicles in various countries.
Mostrar más [+] Menos [-]Powerful toxic activity of citrinin, a fungal phytotoxin, and its mode of action in onion cells Texto completo
2022
Çavuşoğlu, Dilek
The dose-related effects of citrinin (CTN) on various physiological, cytogenetic, biochemical, and anatomical parameters using Allium cepa L. bulbs as a test material were researched in the present study. The physiological parameters examinated were fresh weight, root length, root number, and germination percentage; the cytogenetic parameters were micronucleus (MN) frequency, chromosome aberration (CA), and mitotic index (MI); the biochemical parameters were catalase (CAT), superoxide dismutase (SOD) activities, malondialdehyde (MDA) level, and free proline contents. And the anatomical changes in root tip cells were investigated by cross-sections. For this aim, onion bulbs were splitted four groups as three applications and one control. The bulbs in the control group were treated with distilled water; the bulbs in the application groups were treated with 1 μM, 5 μM, and 10 μM doses of CTN for 7 days. CTN application caused a decrease in the physiological parameters compared to the control group. This treatment created an increase in the frequency of MN and CA, and a reduce in the MI. In addition, it induced a dose-dependent increase in CAT and SOD activities and MDA and proline contents compared to the control group. Moreover, after CTN application, anatomical changes such as flattened nucleus, cell wall thickening, and cell deformation were identified and it was found that these changes reached their maximum at 10 mg/L dose CTN. Concequently, CTN caused inhibitory effects and the Allium test material was found to be a useful bioindicator for monitoring these effects.
Mostrar más [+] Menos [-]Associations between lung-deposited dose of particulate matter and culture-positive pulmonary tuberculosis pleurisy Texto completo
2022
Bai, Kuan-Jen | Tung, Nguyen Thanh | Hsiao, Ta-Chih | Chen, Tsai-Ling | Chung, Kian Fan | Ho, Shu-Chuan | Tsai, Cheng-Yu | Chen, Jen-Kun | Lee, Chun-Nin | Lee, Kang-Yun | Chang, Chih-Cheng | Chen, Tzu-Tao | Feng, Po-Hao | Chen, Kuan-Yuan | Su, Chien-Ling | Thao, Huynh Nguyen Xuan | Dung, Hoang Ba | Thuy, Tran Phan Chung | Lee, Yueh-Lun | Chuang, Hsiao-Chi
Epidemiological studies identified the relationship between air pollution and pulmonary tuberculosis. Effects of lung-deposited dose of particulate matter (PM) on culture-positive pulmonary tuberculosis remain unclear. This study investigates the association between lung-deposited dose of PM and pulmonary tuberculosis pleurisy. A case-control study of subjects undergoing pleural effusion drainage of pulmonary tuberculosis (case) and chronic heart failure (control) was conducted. Metals and biomarkers were quantified in the pleural effusion. The air pollution exposure was measured and PM deposition in the head, tracheobronchial, alveolar region, and total lung region was estimated by Multiple-path Particle Dosimetry (MPPD) Model. We performed multiple logistic regression to examine the associations of these factors with the risk of tuberculosis. We observed that 1-μg/m³ increase in PM₁₀ was associated with 1.226-fold increased crude odds ratio (OR) of tuberculosis (95% confidence interval (CI): 1.023–1.469, p<0.05), 1-μg/m³ increase in PM₂.₅₋₁₀ was associated with 1.482-fold increased crude OR of tuberculosis (95% CI: 1.048–2.097, p < 0.05), 1-ppb increase in NO₂ was associated with 1.218-fold increased crude OR of tuberculosis (95% CI: 1.025–1.447, p < 0.05), and 1-ppb increase in O₃ was associated with 0.735-fold decreased crude OR of tuberculosis (95% CI: 0.542 0.995). We observed 1-μg/m³ increase in PM deposition in head and nasal region was associated with 1.699-fold increased crude OR of tuberculosis (95% CI: 1.065–2.711, p < 0.05), 1-μg/m³ increase in PM deposition in tracheobronchial region was associated with 1.592-fold increased crude OR of tuberculosis (95% CI: 1.095–2.313, p < 0.05), 1-μg/m³ increase in PM deposition in alveolar region was associated with 3.981-fold increased crude OR of tuberculosis (95% CI: 1.280–12.386, p < 0.05), and 1-μg/m³ increase in PM deposition in total lung was associated with 1.511-fold increased crude OR of tuberculosis (95% CI: 1.050–2.173, p < 0.05). The results indicate that particle deposition in alveolar region could cause higher risk of pulmonary tuberculosis pleurisy than deposition in other lung regions.
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