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Effect of microplastics on Yersinia ruckeri infection in rainbow trout (Oncorhynchus mykiss) Full text
2022
Banihashemi, Elham Alsadat | Soltanian, Siyavash | Gholamhosseini, Amin | Banaee, Mahdi
Exposure to microorganisms such as Yersinia ruckeri can significantly affect bacterial infections in fish. Microplastics (MPs) may predispose fish to infection and act as carriers in pathogen transmission. Therefore, this study is designed to evaluate MPs’ effect on damage caused by exposure to Y. ruckeri in rainbow trout. In this study, blood biochemical parameters and hepatic oxidative biomarkers as clinical signs were measured in the fish co-exposed to Y. ruckeri (5 and 10% the median lethal dose (LD₅₀)) and MPs (500 and 1000 mg Kg⁻¹) for 30 days. There were no significant changes in the creatinine, triglyceride, cholesterol levels, and glutamic-pyruvic transaminase activity in the blood of fish infected with Y. ruckeri. In contrast, exposure to MPs had a significant effect on most clinical parameters. The total protein, albumin, globulin, total immunoglobulins, high-density lipoprotein, low-density lipoprotein, cholesterol levels, and γ-glutamyltransferase activity decreased, whereas glucose, triglyceride, and creatinine levels, and glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase, alkaline phosphatase, and lactate dehydrogenase activities increased in the plasma of fish after co-exposure to MPs and Y. ruckeri. Dietary MPs combined with a Y. ruckeri challenge decreased catalase and glutathione peroxidase activities, and total antioxidant levels. However, superoxide dismutase activity and malondialdehyde contents increased in the hepatocyte of fish co-exposed to MPs and Y. ruckeri. This study suggests that fish exposure to MPs and simultaneous challenge with Y. ruckeri could synergistically affect clinical parameters.
Show more [+] Less [-]From wastes to functions: preparation of layered double hydroxides from industrial waste and its removal performance towards phosphates Full text
2022
Xiao, Liping | Li, Yan | Kong, Qiaoping | Lan, Yunlong
To control eutrophication and recover phosphate from wastewater, a calcium carbide slag and red mud composite material (CR-LDH) was prepared using industrial waste as raw material for phosphorus adsorption. The morphology and structure of synthesized CR-LDH were characterized by FT-IR, SEM, EDS, and XRD measurements. Bath adsorption test results showed that the optimal dosages of adsorbent and pH for phosphate were 5 g·L⁻¹ and pH of 7, respectively. The experimental data could be well described by pseudo-second-order kinetic and Langmuir isotherm models, suggesting that the adsorption process of CR-LDH with respect to phosphate was a chemical and monolayer process. The theoretical maximum adsorption capacity obtained by Langmuir isotherm model was 16.06 mg·g⁻¹ at 25 °C. The intra-particle diffusion model fitting results indicated that the adsorption of phosphate by CR-LDH was controlled by both liquid membrane diffusion and intra-particle diffusion. Phosphate was bound to CR-LDH via synergistic effect of physical adsorption, ion exchange, anion intercalation, and chemical precipitation as evidenced from a combination of microscopic analysis and adsorption mechanism study. The actual phosphate-containing wastewater investigation showed that CR-LDH not only exhibited good removal effect on phosphate, but also could greatly reduce turbidity, COD, and ammonia nitrogen, which was suitable for disposal of practical wastewater. The COD, turbidity, and NH₄⁺-N could be reduced by 42.39%, 77.20%, and 20.71%, respectively. These results indicate that CR-LDH can be considered as potential adsorbent for the treatment of phosphate-containing wastewater, which will be helpful to achieve the goal of “treating waste with waste and turning waste into treasure”.
Show more [+] Less [-]Conformance of sowing dates for maximizing heat use efficiency and seed cotton yield in arid to semi-arid cotton zone of Pakistan Full text
2022
Mudassir, Muhammad Akhlaq | Rasul, Fahd | Khaliq, Tasneem | Yaseen, Muhammad
Pakistan is placed among the most vulnerable countries with relation to climate change and its impacts on agricultural productivity. Cotton is staged as the cash crop of the country and the main source of raw material for textile, oil, and feed industry. Varying environmental attributes have significant effects on the duration of vegetative and reproductive stages of cotton crop. To evaluate the potential impacts of varied temperatures regimes in different sowing times, field experiments were carried out throughout the cotton growing areas of Pakistan from Faisalabad in Central Punjab to RYK in Southern Punjab and Sakrand in Sindh to Dera Ismail Khan in Khyber Pakhtunkhwa (KPK) Province. Crop was sown on six different sowing dates starting from 1st March towards 15th May with 2-week intervals for two crop seasons (2016 and 2017). The timing of phenological events like emergence, squaring, flowering, and boll opening was recorded on calendar days and cumulative heat units (GDDs) were calculated for flowering and boll opening stages. Heat use efficiency for these sowing times was estimated. Data regarding yield-related parameters like opened bolls per plant, average boll weight, and seed cotton yield were also recorded during the study. Results revealed that duration of the growth stages was significantly affected by variation in mean thermal kinetics in varied sowing times in all four different environments. Seed cotton yield and heat use efficiency were also varied among the locations and sowing dates. The maximum seed cotton yield was recorded in Sakrand location at 15th April sowing date. The dependence of the phenological advancement on temperature and negative impacts of higher thermal stress on cotton productivity were also confirmed throughout the cotton growing zone of Pakistan.
Show more [+] Less [-]Industrialization, servicification, and environmental Kuznets curve: non-linear panel regression analysis Full text
2022
Taşdemir, Fatma
This paper investigates whether the impact of income on CO₂ emissions is invariant to endogenously estimated threshold levels for the economic structure (ES) represented by value added in manufacturing, industry, and service sector shares in GDP for a panel of 54 economies over the 1971–2017 period. Our panel smooth transition regression estimation results strongly suggest that the sensitivity of CO₂ emissions to income is substantially much higher in countries with higher manufacturing and industry sector shares, whilst it is much lower in servicified economies. Given the argument that manufacturing is the engine of growth, this finding may not necessarily downgrade the crucial importance of an industrial policy which places the manufacturing at the core. The empirical findings in this paper suggest that countries may better to design and implement a strategic and systematic industrial policy which promote the use of emission reduction technologies and encourage manufacturing and industrial sectors with lower carbon emissions.
Show more [+] Less [-]Mercury accumulation in muscle and liver tissue and human health risk assessment of two resident freshwater fish species in Flanders (Belgium): a multilocation approach Full text
2022
Teunen, Lies | Belpaire, Claude | De Boeck, Gudrun | Blust, Ronny | Bervoets, Lieven
Detrimental effects of chemical pollution—primarily caused by human activities—on aquatic ecosystems have increasingly gained attention. Because of its hydrophobic qualities, mercury is prone to easily bioaccumulate and biomagnify through the food chain, decreasing biodiversity and eventually also affecting humans. In the present study, accumulated mercury concentrations were measured in muscle and liver tissue of perch (Perca fluviatilis) and European eel (Anguilla anguilla) collected at 26 sampling locations in Flemish (Belgian) waterbodies, allowing a comparison of these species within a variety of environmental situations. Furthermore, effects of size and weight have been assessed, expected to influence accumulation and storage of pollutants. Mercury concentrations in perch ranged up to 1.7 μg g⁻¹ dw (median: 0.29 μg g⁻¹ dw) in muscle and from 0.02 to 0.77 μg g⁻¹ dw (median: 0.11 μg g⁻¹ dw) in liver tissue. For eel, these concentrations were between 0.07 and 1.3 μg g⁻¹ dw (median: 0.39 μg g⁻¹ dw) and between 0.08 and 1.4 μg g⁻¹ dw (median: 0.55 μg g⁻¹ dw) respectively. We found a correlation of accumulated mercury with length in perch, independent of location. Furthermore, a significant difference in accumulated mercury concentrations between the targeted species was measured, with the highest mean concentrations per dry weight in eel liver and muscle tissue. In perch, higher concentrations were found in muscle compared to liver tissue, while in eel, liver tissue showed the highest concentrations. These findings were further considered with concentrations corrected for lipid content, excluding the fat compartment, which is known to a hold negligible portion of the total and methyl mercury concentrations. This confirmed our previous conclusions, except for mercury concentrations in eel. Here there was no longer a significant difference between muscle and liver concentrations. Finally, health risk analyses revealed that only frequent consumption of local eel (> 71 g day⁻¹) could pose risks to humans.
Show more [+] Less [-]Photocatalytic degradation of imidacloprid by optimized Bi2WO6/NH2-MIL-88B(Fe) composite under visible light Full text
2022
Chen, Mao-Long | Lu, Tian-Hui | Li, Shan-Shan | Wen, Li | Xu, Zhou | Cheng, Yun-Hui
Imidacloprid as a widely used neonicotinoid insecticide can cause harmful pesticide residue inevitably. Metal-organic frameworks (MOFs) were innovatively composited to improve the light absorption and degradation performance of Bi₂WO₆ semiconductor, which expanded the photodegradation application in solving environmental problems. Based on the synergistic effect of Bi₂WO₆ and NH₂-MIL-88B(Fe), a Bi₂WO₆/NH₂-MIL-88B(Fe) (BNM) heterojunction photocatalyst with high-performance of photocatalytic degradation activities was successfully synthesized. The optimized BNM catalyst had a good degradation rate under visible light, which was mainly caused by generation of the active ·OH. Transient photocurrent response and electrochemical impedance tests verified that 1:2 BNM exhibits a highest charge separation and a lowest carrier recombination rate which were favorable to the photocatalytic activity. Cycle experiments show that the composite photocatalyst had good reusability and stability which were very important for potential industry applications.
Show more [+] Less [-]Etofenprox as grain protectant for the management of five key stored-product insect pests Full text
2022
Boukouvala, Maria C. | Kavallieratos, Nickolas G.
Etofenprox is a broad spectrum pyrethroid insecticide with low toxicity to mammals, fishes, and honeybees. In the present study it was evaluated as grain protectant against Ephestia kuehniella (Lepidoptera: Pyralidae) larvae, Prostephanus truncatus (Coleoptera: Bostrychidae) adults, Rhyzopertha dominica (Coleoptera: Bostrychidae) adults, Sitophilus oryzae (Coleoptera: Curculionidae) adults, and Tribolium confusum (Coleoptera: Tenebrionidae) larvae and adults. Etofenprox was applied at 0.1, 1, 5, and 10 ppm on wheat, or maize in the case of P. truncatus, and tested at different combinations of temperatures (20, 25, and 30 °C) and relative humidity (RH) levels (55 and 75%). Progeny production of the tested coleopteran adult species was also assessed. For E. kuehniella, after 21 days of exposure 75.6% of the exposed larvae were killed at 20 and 30 °C/55% RH. Mortality of P. truncatus adults reached 99.4 and 97.8% at 10 ppm of 55 and 75% RH, respectively, at 30 °C. For S. oryzae, after 21 days of exposure, mortality was moderate at both RH levels, even at the elevate doses, reaching 66.7% at 10 ppm at 20°C/75% RH. All R. dominica adults died 21 days post-exposure at 30°C/55% RH and 25 or 30°C/75% RH at 10 ppm. For T. confusum adults, mortality was 81.1% 10 ppm 21 days post-exposure at 20°C/75% RH. Etofenprox killed 99.4% of the exposed T. confusum larvae at 10 ppm respectively 14 days post-exposure at 25°C/55% RH. Concerning progeny production, complete suppression was recorded for P. truncatus, R. dominica, and T. confusum in various combinations of temperature/RH. Our findings indicate that etofenprox is a well-promising insecticide for the protection of stored grains. However, its performance differs among insect species and abiotic conditions.
Show more [+] Less [-]Genotoxicity assessment in two Amazonian estuaries using the Plagioscion squamosissimus as a biomonitor Full text
2022
de Oliveira, Claudia Antonia Campos Rodrigues | dos Santos Souto, Paulo Sérgio | da Conceição Palheta, Dulcidéia | de Oliveira Bahia, Marcelo | da AraújoCunha, Lorena | de Lourdes Souza Santos, Maria | do Nascimento Medeiros Rodrigues, Tatiane | Bentes, Bianca
Genotoxicity studies in coastal ecosystems have been a priority in Environmental Risk Assessment (ERA). This research aimed to study the genotoxicity by the micronucleus test and comet assay in two Brazilian Amazon estuaries (anthropized and control) using Plagioscion squamosissimus as a biomonitor. Blood samples were collected from 54 specimens. No significant genotoxic effects were detected in the cells analyzed, although the highest occurrence (MN and DNA damages) was observed in anthropized site. The percentage of genomic damage differed between the sites studied, being always higher in anthropizes site as well. Of the nucleoids analyzed in this site, on average, 28 ± 14.42% of the cells were classified in the highest damage class. The fish analyzed in the present study are direct influenced of xenobiont agents capable of producing damage to the genetic material of aquatic organisms in both sites and, consequently, may bring consequences still little reported in studies of morphophysiological alterations in humans.
Show more [+] Less [-]Negative air ion exposure ameliorates depression-like behaviors induced by chronic mild stress in mice Full text
2022
Hu, Yun-Qing | Niu, Ting-Ting | Xu, Jian-ming | Peng, Li | Sun, Qing-Hua | Huang, Ying | Zhou, Ji | Ding, Yu-Qiang
The presence of negative air ions (NAI) is suggested to be a beneficial factor in improving psychological status and used in treating depression as an alternative approach. However, more biological evidence from animal models is needed to ensure the effects of NAI on the mood regulation, through which can facilitate identification of possible underlying mechanisms. In this study, the chronic mild stress (CMS) protocol was used to induce depressive-like behaviors in mice, and the effects of NAI exposure on CMS-induced depression-like behaviors were examined. Thirty-day NAI exposure prevented the CMS-induced depression-like behaviors as shown by the restoration of sucrose preference and reduced immobility time in the tail suspension test. In addition, the elevation of serous corticosterone was present in CMS-treated mice but not existed in those with the NAI exposure. Furthermore, we observed altered ratios of some cytokines secreted by type 1 T helper (Th1) cells and Th2 cells in CMS-treated mice, but it could be restored after NAI exposure. In conclusion, NAI intervention is able to ameliorate CMS-induced depression-like behaviors in mice, and this effect is associated with the alteration of corticosterone and functional rebalance between Th1 and Th2 cells.
Show more [+] Less [-]Establishing a corporate social responsibility implementation model for promoting sustainability in the food sector: a hybrid approach of expert mining and ISM–MICMAC Full text
2022
Usmani, Muhammad Shahjahan | Wang, Jianling | Ahmad, Naveed | Ullah, Zia | Iqbal, Muzaffar | Ismail, Muhammad
Corporate social responsibility (CSR) is significantly related to food companies due to its prominent impact and greater dependency on the environment, economy, and society (triple bottom line — TBL). The CSR-related threats and opportunities’ scale are shifting from single companies to networks and supply chains of the food sector. In this regard, this study empirically evaluates CSR initiatives by using Interpretive Structural Modeling (ISM) and Matrice d’Impacts Croisés Multiplication Appliqués à un Classement (MICMAC) methodology. So to develop an ISM–MICMAC-based framework, at first, CSR initiatives were chosen from existing literature with experts’ advice. Later, MICMAC analysis results showed that “employee trainings and workshops” and “employee welfare and empowerment” are significant CSR initiatives that could help CSR’s integration in the food sector of Pakistan, whereas CSR initiatives “community betterment” and “contribution towards economic development” proved least significant in the model. This study recommends that food sector firms should promote employee-based strategies in the firms. Moreover, the empirical findings of this study help to better understand CSR initiatives and their role in the implementation of CSR in the food sector of developing countries.
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