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Responses of ajowan (Trachyspermum ammi L.) to exogenous salicylic acid and iron oxide nanoparticles under salt stress Полный текст
2020
Abdoli, Soheila | Ghassemi-Golezani, Kazem | Alizadeh-Salteh, Saeideh
This research with a factorial arrangement was undertaken to investigate physiological responses of ajowan plants to foliar treatment of salicylic acid (1 mM) and nano-Fe₂O₃ (3 mM) under various salinity levels (0, 4, 8, 12 dS m⁻¹ NaCl, respectively). Rising salinity enhanced sodium and endogenous SA contents, soluble sugars, protein, glycine betaine, proline, antioxidant enzymes activities, ROS generation, and lipid peroxidation, while reduced potassium and iron contents, membrane stability index, leaf water content, leaf pigments, root and shoot biomasses, and seed yield. Application of particularly SA and SA+nano-Fe₂O₃ alleviated salt toxicity via enhancing K⁺ uptake, K⁺/Na⁺ ratio, Fe content, endogenous level of SA, the activities of antioxidant enzymes (superoxide dismutase, catalase, peroxidase, and polyphenol oxidase), and most of the osmolytes. These changes were resulted in improving membrane stability index, leaf water content, leaf pigments, root and shoot growth, and finally seed yield of plants under moderate and severe salinities. Therefore, these treatments can additively enhance salt tolerance and physiological performance of ajowan through increasing antioxidant capacity, osmolytes, and photosynthetic pigments. Graphical Abstract .
Показать больше [+] Меньше [-]Defect minimized Ag-ZnO microneedles for photocatalysis Полный текст
2020
Ullattil, Sanjay Gopal | Jabeen Fatima M. J., | Abdel-Wahab, Ahmed
A facile solution processing strategy has been developed for the formation of Ag-modified ZnO microneedles at various calcination temperatures such as 300, 500, and 700 °C (AZ3, AZ5, and AZ7 respectively). Due to the heavy doping of AgNO₃, Ag⁺ ions have been incorporated in to the crystal lattice of ZnO in all the Ag-ZnO samples, which facilitated the formation of Ag-ZnO microneedle morphology with minimized defect states, and obviously, the plasmon peaks were observed due to Ag modification. These Ag-ZnO microneedle structures have been evaluated for their photocatalytic performance using methylene blue as model target contaminant and their activity was compared with the commercially available titania P25 photocatalyst. The photoactivity of all the Ag-ZnO microneedle structures was significantly higher than that of the commercially available P25 photocatalyst with the most active Ag-ZnO material having a photocatalytic activity ~ 1.4 times greater than that of P25 titania.
Показать больше [+] Меньше [-]Development and characterisation of a nanostructured hybrid material with vitamin B12 and bagasse-derived activated carbon for anaerobic chlordecone (Kepone) removal Полный текст
2020
Ranguin, Ronald | Ncibi, Mohammed Chaker | Cesaire, Thierry | Lavoie, Serge | Jean-Marius, Corine | Grützmacher, Hansjörg | Gaspard, Sarra
Intensive use of the chlorinated pesticide chlordecone from the 1970s to 1993 to prevent crop damage in banana plantations of Guadeloupe and Martinique led to diffuse pollution of soils and surface waters, affecting both fauna and human beings in the contaminated areas. Since 2001, drinking water production plants have been equipped with filters containing activated carbon that must be treated after saturation. The objective of this work is to produce a hybrid material composed of activated carbon and vitamin B12 (VB12) for the degradation of chlordecone (CLD). The preparation of such a hybrid material is carried out by non-covalent fixation to achieve an eco-friendly solution for the serious environmental problem of contamination by chlorinated pesticides. It is thus proposed to degrade CLD by a physico-chemical treatment allowing salvage of the catalyst, which is adsorbed on the carbon surface to generate less waste that is inexpedient to treat. Activated carbon (AC) is produced locally from available sugarcane bagasse subjected to phosphoric acid activation. The main characteristics of this material are a major mesoporous structure (0.91%) and a specific (BET) surface area ranging from 1000 to 1500 m² g⁻¹. The experimental results showed that BagP1.5 has a high adsorption capacity for VB12 due to its large surface area (1403 m² g⁻¹). The binding of VB12 to the bagasse-derived AC is favoured at high temperatures. The adsorption is optimal at a pH of approximately 6. The maximum adsorption capacity of VB12 on the AC, deduced from the Langmuir model, was 306 mg g⁻¹, confirming the high affinity between the two components. The hybrid material was characterised by FTIR, Raman, X-ray fluorescence spectroscopy and SEM analysis. CLD removal by this hybrid material was faster than that by VB12 or BagP1.5 alone. The CLD degradation products were characterised by mass spectrometry.
Показать больше [+] Меньше [-]Transport and distribution of manganese in tidal estuarine system in Taiwan Полный текст
2020
Liu, Wenzheng | Ken, Poi-Jiu | Liu, Hong-Ming
Based on the observed heavy metals in the Danshui River estuarine system, the concentration of manganese (Mn) exceeds the water quality standards. High concentrations of manganese in aquatic environment can cause disturbances in the sodium balance, disturb the metabolism of carbohydrates, and impair the immunological functions of fish. Therefore, a three-dimensional heavy metal transport model was developed and incorporated into the hydrodynamics, salinity, and suspended sediment transport model to evaluate the concentration distribution of the heavy metal manganese (Mn) in the Danshui River estuarine system of northern Taiwan. The model was validated with observational data for water level, tidal current, salinity, suspended sediment concentration, and heavy metal (Mn) concentration that was measured in 2015. The indicators of statistical error, including mean absolute error (MAE), root mean square error (RMSE), and skill score (SS), were adopted to evaluate the model performance. There was good quantitative agreement between the simulation results and measurements. Sensitivity analysis of suspended sediment and heavy metal transport model was carried out to understand which parameters were important to be cautiously determined. Furthermore, the validated model was used to investigate the influence of suspended sediment on the concentration distribution of heavy metals (Mn) in tidal estuaries. If the suspended sediment transport module was excluded in model simulations, the predicted results for the heavy metal (Mn) concentration underestimated the measured data. The modeling results showed that the inclusion of the suspended sediment transport module in the model simulations was critically important to the results of the heavy metal (Mn) concentration in the tidal estuarine system in Taiwan.
Показать больше [+] Меньше [-]Efficiency of a solar collector system for the public building depending on its location Полный текст
2020
Krawczyk, Dorota Anna | Żukowski, Mirosław | Rodero Franganillo, Antonio
Due to a technologic progress, a growth in the renewable energy markets including a high number of manufactures coming to being, the Renewable Energy Sources (RES) are both a tool for mitigating climate changes and investments that can provide direct economic profits and reduce a political or economic dependence resulting from import of fossil fuels. One of the many key solutions toward fulfilling the global increasing demand for energy and reduction of CO₂ emissions is applying solar technologies. This paper presents the results of the analysis conducted for a small public office building located in Bialystok (Poland), where solar collectors were considered as the RES for domestic hot water (DHW) system, on the understanding that existing oil boiler would be an additional source. Low values of recommended water consumption in office buildings resulted in a low energy demand. However, concerning a potential of all office governmental buildings in Poland, it would be possible to reduce CO₂ emission by 17,248 tonnes. In the comprehensive analysis, the same building in two more locations (Cordoba (Spain) and Kaunas (Lithuania)) was considered using simulation tools delivered within the framework of VIPSKILLS project as well as EnegyPlus software. The results allow to compare the mean monthly efficiency of systems or number of collectors necessary to deliver similar amount of solar energy.
Показать больше [+] Меньше [-]Modulatory role of dietary Thymus vulgaris essential oil and Bacillus subtilis against thiamethoxam-induced hepatorenal damage, oxidative stress, and immunotoxicity in African catfish (Clarias garipenus) Полный текст
2020
El Euony, Omnia I. | Elblehi, Samar S. | Abdel-Latif, Hany M. | Abdel-Daim, Mohamed M. | El-Sayed, Yasser S.
Thiamethoxam (TMX) is a widely used neonicotinoid insecticide for its effective potential for controlling insects from the agricultural field, which might induce toxicity to the aquatic biota. In this study, the role of the probiotic Bacillus subtilis (BS) and a phytogenic oil extract of Thymus vulgaris essential oil (TVEO) in the modulation of thiamethoxam (TMX)-induced hepatorenal damage, oxidative stress, and immunotoxicity in African catfish (Clarias garipenus) has been evaluated. Fish were subjected to TMX (5 mg L⁻¹) and fed with a diet either supplemented with BS (1000 ppm) or TVEO (500 ppm). The experiment lasted for 1 month. By the end of the experiment, blood was sampled for biochemical analysis and fish organs and tissues were collected for histopathological and immunohistochemical examinations. Results showed a substantial increase of serum markers of hepatorenal damage such as the activities of aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP) and levels of blood urea nitrogen (BUN) and creatinine with an obvious decrease of serum protein levels in the TMX-intoxicated group. Also, there was a considerable increase in malondialdehyde (MDA) levels and glutathione-S-transferase (GST) activity. TMX remarkably suppressed serum lysozyme activity, respiratory burst activity, and phagocytosis with a conspicuous elevation of the levels of interleukins (interleukin-1 beta (IL-1β) and interleukin-6 IL-6). The histopathological findings showed that TMX induced degenerative changes and necrosis in the gills, liver, head kidneys, and spleen of the intoxicated fish. Significant alterations of frequency, size, and area percentage of melanomacrophage centers (MMCs), decreased splenocyte proliferation, and increased number of caspase-3 immunopositive cells were also observed. Contrariwise, the concurrent supplementation of either BS or TVEO in the diets of catfish partially mitigated both the histopathological and histomorphometric lesions of the examined tissues. Correspondingly, they improved the counts of proliferating cell nuclear antigen (PCNA) and caspase-3 immunopositive splenocytes. In conclusion, the co-administration of either BS or TVEO in catfish diets partially diminished the toxic impacts of TMX. Nonetheless, the inclusion of TVEO in the diets of catfish elicited better protection than BS against TMX-induced toxicity in response to its potential anti-inflammatory, antioxidant, anti-apoptotic, and immune-stimulant effects.
Показать больше [+] Меньше [-]Evaluation of groundwater sustainable development considering seawater intrusion in Beihai City, China Полный текст
2020
Ma, Chuangming | Li, Yonggang | Li, Xuan | Gao, Lin
The overmining of groundwater makes the aquifer in a coastal area prone to seawater intrusion and further leads to deterioration of water quality and ecosystem degradation. However, the vulnerability evaluation of seawater intrusion can provide a scientific basis for the prevention of seawater intrusion, and then ensure the sustainable use of groundwater. In this paper, Baihai City was taken as the study area, and the analytic hierarchy process (AHP), variable power theory, and fuzzy comprehensive evaluation method were used synthetically. The vulnerability of seawater intrusion in the study area was divided into lowest vulnerability, low vulnerability, medium vulnerability, and high vulnerability, and these correspond to 1739.98, 133.88, 664.32, and 737.55 km². On this basis, combined with the groundwater quality and quantity and ecosystem of the study area, the groundwater is divided into concentrated groundwater supply area (8.16%), decentralized groundwater supply area (12.44%), protected area (78.94%), and reserved zone (0.45%), which can provide the basis for the rational exploitation and management of groundwater. By analyzing the results of constant right and variable weight evaluation, combined with the history of seawater intrusion, it is proved that the variable weight evaluation model can effectively solve the unreasonable situation caused by the internal differences of the indicator, so that the evaluation results are more in line with reality. In addition, the application of the fuzzy comprehensive evaluation method makes the evaluation results clearer.
Показать больше [+] Меньше [-]Research on the relationship between energy consumption and air quality in the Yangtze River Delta of China: an empirical analysis based on 20 sample cities Полный текст
2020
He, Lingyun | Yin, Fang | Wang, Deqing | Yang, Xiaolei | Xie, Fengmin
This paper uses static and dynamic panel regression to measure the effect of energy consumption on air quality of 20 heavily polluted cities in the Yangtze River Delta of China. Further, the influence of the relevant policies on the relationship between energy consumption and air quality is tested with the method of regression discontinuity. This study concluded the following: (1) When energy consumption structure, industrial structure, and energy efficiency are taken into account, the effect coefficient of energy consumption on air quality is 0.4579, meaning that controlling energy consumption tends to improve the air quality positively. (2) The emission of sulfur dioxide is characterized by inertia; the annual increase in sulfur dioxide emissions in the previous year will lead to an increase of 0.427% in the annual emissions. (3) The relationship between energy consumption and air quality of different cities varies, and these cities can be divided into four categories. (4) The relevant policies for improving air quality are effective to some extent. This study indicates that the Yangtze River Delta should focus on actively changing the mode of energy development.
Показать больше [+] Меньше [-]Impact of environmental contaminants on reproductive health of male domestic ruminants: a review Полный текст
2020
Guvvala, Pushpa Rani | Ravindra, Janivara Parameswaraiah | Selvaraju, Sellappan
Environmental contaminants are gaining more attention in the livestock sector lately due to their harmful effects on productivity and fertility of livestock. Recent research indicates that many domestic ruminants are becoming subfertile/infertile due to confounding reasons associated with management. Contaminants like metals, metalloids, herbicides, pesticides, insecticides, chemicals, or natural contaminants are present everywhere in day to day life and are becoming a threat to the livestock. Studies on a broad-spectrum of animals suggest that high doses of acute or low doses of chronic exposure to the contaminants lead to disruption of multi-organs/systems including reproductive function. The lowered reproductive efficiency in animals is attributed to the endocrine disruptor activities of the environmental contaminants on the gonads, affecting gametogenesis and steroidogenesis. In vitro studies on testicular cells and the semen suggest that spermatozoa are more susceptible to damage by environmental contaminants. The quality of the semen happens to be a critical factor in the livestock industry. Contaminants affecting gametogenesis and steroidogenesis may lead to devastating consequences to the livestock reproduction, and thus the production. However, there is a lack of collective data on the effect of such environmental contaminants on the fertility of male domestic ruminants. This review discusses the studies related to the impact of environmental contaminants on male fertility in large (bull and buffalo) and small (sheep and goat) ruminants by focusing on the underlying molecular interactions between the contaminants and gonads.
Показать больше [+] Меньше [-]The relationship between climate change and political instability: the case of MENA countries (1985:01–2016:12) Полный текст
2020
Sofuoğlu, Emrah | Ay, Ahmet
The aim of this study is to examine the relationship between climate change and political instability in the MENA region. To this extent, 18 Middle East and North African (MENA) countries are analyzed covering the period 1985:01–2016:12 with monthly data. In econometric analysis, at first cross-sectional dependency analysis is applied, and existence of cross-sectional dependency among countries is found. Therefore, CADF-second generation panel unit root test applied, and finally, Dumitrescu and Hurlin (2012) panel causality test that consider the cross-sectional dependency are utilized. For empirical analysis, temperature and precipitation data representing climate change, political instability, and conflict data are employed. According to the findings, there is a causal relationship from climate change to political instability in 16 countries and to conflict in 15 countries. In addition to this, at least one causal relationship is determined from climate change to political instability or conflict in all MENA countries. Therefore, empirical results support the assumption that climate change acts as a threat multiplier in MENA countries since it triggers, accelerates, and deepens the current instabilities.
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