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The effect of anaerobic digestion and storage on indicator microorganisms in swine and dairy manure Полный текст
2017
Costa, Annamaria | Gusmara, Claudia | Gardoni, Davide | Zaninelli, Mauro | Tambone, Fulvia | Sala, Vittorio | Guarino, Marcella
The aim of this experimental study was to evaluate the influence of anaerobic digestion and storage on indicator microorganisms in swine and dairy excreta. Samples were collected every 90 days for 15 months at eight farms, four pig, and four dairy farms, four of them having a biogas plant. Moreover, to evaluate storage effects on samples, 20 l of manure and slurry taken at each farm (digested manure only in farms with a biogas plant) were stored in a controlled climatic chamber at 18 °C, for 6 months. The bacterial load and the chemical-physical characteristics of excreta were evaluated at each sampling time, stored slurry, and manure were sampled and analyzed every 2 months. A high variability of the concentration of bacteria in the different excreta types was observed during the experiment, mainly depending on the type and time of treatment. No sample revealed either the presence of Escherichia coli O157:H7 or of Salmonella, usually linked to the temporary rearing of infected animals in facilities. Anaerobic digestion and storage affected in a significant way the reduction of indicator bacteria like lactobacilli, coliforms, and streptococci. Anaerobic digestion lowered coliforms in pig slurry (− 2.80 log, P < 0.05), streptococci in dairy manure (− 2.44 log, P < 0.001) and in pig slurry (− 1.43 log, P < 0.05), and lactobacilli in pig slurry (− 3.03 log, P < 0.05). Storage lowered coliforms and the other indicators counts, in particular in fresh wastes, while clostridia did not show a reduction in concentration.
Показать больше [+] Меньше [-]Biofuel consumption, biodiversity, and the environmental Kuznets curve: trivariate analysis in a panel of biofuel consuming countries Полный текст
2017
Zaman, Khalid
This study examined the relationship between biofuel consumption, forest biodiversity, and a set of national scale indicators of per capita income, foreign direct investment (FDI) inflows, trade openness, and population density with a panel data of 12 biofuels consuming countries for a period of 2000 to 2013. The study used Global Environmental Facility (GEF) biodiversity benefits index and forest biodiversity index in an environmental Kuznets curve (EKC) framework. The results confirmed an inverted U-shaped relationship between GEF biodiversity index and per capita income, while there is flat/no relationship between carbon emissions and economic growth, and between forest biodiversity and economic growth models. FDI inflows and trade openness both reduce carbon emissions while population density and biofuel consumption increase carbon emissions and decrease GEF biodiversity index. Trade openness supports to increases GEF biodiversity index while it decreases forest biodiversity index and biofuel consumption in a region.
Показать больше [+] Меньше [-]Psychoactive drugs: occurrence in aquatic environment, analytical methods, and ecotoxicity—a review Полный текст
2017
Cunha, Deivisson Lopes | de Araujo, Frederico Goytacazes | Marques, M. (Marcia)
This review focused on seven psychoactive drugs being six benzodiazepines (alprazolam, bromazepam, clonazepam, diazepam, lorazepam, and oxazepam) and one antidepressant (citalopram) widely consumed by modern society and detected in different aqueous matrices (drinking water, surface water, groundwater, seawater, estuary water, influent and effluent of wastewater treatment plants). The review included 219 selected scientific papers from which 1642 data/entries were obtained, each entry corresponding to one target compound in one aqueous matrix. Concentrations of all investigated drugs in all aqueous matrices varied from 0.14 to 840,000 ng L⁻¹. Citalopram presented the highest concentrations in the aqueous matrices. Based on the Wilcoxon-Mann-Whitney test, differences between wastewater influents and effluents were not significant for most wastewater categories, suggesting that conventional wastewater treatment systems as such do not remove or remove partially these compounds. High-income countries showed much lower concentrations in surface water than the group formed by upper-middle-, lower-middle-, and low-income countries. Regarding analytical methods, solid-phase extraction (SPE) was by far the most used extraction method (83%) and performance liquid chromatography (HPLC) (73%) coupled to mass spectrometry (99%) the most common analytical method. Changes in behavior and in survival rates were the most common effects reported on bioindicators (aquatic species) due to the presence of these drugs in water. Concentrations of psychoactive drugs found in surface waters were most of the time within the range that caused measurable toxic effects in ecotoxicity assays.
Показать больше [+] Меньше [-]Impairment of mitochondrial integrity and redox status in brain regions during a low-dose long-term exposition of rats to pyrethrinoïds: the preventive effect of quercetin Полный текст
2017
Beghoul, Afafe | Kebieche, Mohamed | Gasmi, Salim | Chouit, Zeyneb | Amiour, Chouaib | Lahouel, Asma | Lakroun, Zhora | Rouabhi, Rachid | Fetoui, Hamadi | Soulimani, Rachid
Impairment of mitochondrial integrity and redox status in brain regions during a low-dose long-term exposition of rats to pyrethrinoïds: the preventive effect of quercetin Полный текст
2017
Beghoul, Afafe | Kebieche, Mohamed | Gasmi, Salim | Chouit, Zeyneb | Amiour, Chouaib | Lahouel, Asma | Lakroun, Zhora | Rouabhi, Rachid | Fetoui, Hamadi | Soulimani, Rachid
Pyrethrinoïds are synthetic pesticides widely used in agriculture and farms to protect crops from weeds, insects, fungi, and molds. Increased and uncontrolled use of these pollutants can have harmful effects on human health via consumption of contaminated food products. In the present study, deltamethrin (DLT = 3.72 mg/kg) and Bifenthrin (BF = 2.6 mg/kg) were used during a long-term exposition in the rats to assess their effect on mitochondrial integrity and function in different brain areas (hippocampus, striatum, cortex, and cerebellum). The results of this study have shown that chronic treatment of rats by both DLT and BF, on their own or in a mixture, has induced a significant increase in mitochondrial MDA, but when quercetin (Que) was co-administered with pesticides, this enhancement has been prevented in the almost of treated rats compared to solvent and control groups. In hippocampus area, GSH has significantly increased in all treated rats, except for BF and DLT-Que.-treated groups. In striatum, GSH has been depleted in the BF and DLT-treated groups compared to control and solvent groups; in contrast, when Que. was associated with pesticides, the rate of this tripeptide has been maintained at normal levels. In the cortex and cerebellum, GSH has been depleted significantly in all treated animals but has increased in DLT-Que. and mixture-Que.-treated groups in the cerebral cortex, at the same time; it has been maintained at normal levels in BF-Que.-treated groups in the cerebellum compared to control and solvent rats. On the other side, the results of this study have shown a loss of catalase (CAT) and glutathione S-transferase (GST) activities in all brain regions of pesticide-treated rats, but such a fall in enzymatic activities has been prevented by Que. when it was co-administered to rats with pesticides at the dose of 5 mg/kg, except in the cerebellum. In addition, this study has shown mitochondria’s swelling in almost all the brain areas with exception of the cerebellum, providing information about a loss of mitochondrial membrane integrity in brain neurons of rats exposed to pyrethrinoïds. Furthermore, preventive administration of Que., in association with pesticides (5 mg/kg) or their mixture (10 mg/kg), has prevented mitochondria swelling in almost all of the analyzed brain tissues.
Показать больше [+] Меньше [-]Impairment of mitochondrial integrity and redox status in brain regions during a low-dose long-term exposition of rats to pyrethrino < ds: the preventive effect of quercetin Полный текст
2017
Beghoul, Afafe | Kebieche, Mohamed | Gasmi, Salim | Chouit, Zeyneb | Amiour, Chouaib | Lahouel, Asma | Lakroun, Zhora | Rouabhi, Rachid | Fetoui, Hamadi | Soulimani, Rachid | Université Mohammed Seddik Benyahia [Jijel] | University of Jijel (UMSBJ) | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | University of Tebessa ; Partenaires INRAE | جامعة صفاقس - Université de Sfax - University of Sfax | Institut National de la Recherche Agronomique (INRA)
International audience | Pyrethrino < ds are synthetic pesticides widely used in agriculture and farms to protect crops from weeds, insects, fungi, and molds. Increased and uncontrolled use of these pollutants can have harmful effects on human health via consumption of contaminated food products. In the present study, deltamethrin (DLT = 3.72 mg/kg) and Bifenthrin (BF = 2.6 mg/kg) were used during a long-term exposition in the rats to assess their effect on mitochondrial integrity and function in different brain areas (hippocampus, striatum, cortex, and cerebellum). The results of this study have shown that chronic treatment of rats by both DLT and BF, on their own or in a mixture, has induced a significant increase in mitochondrial MDA, but when quercetin (Que) was co-administered with pesticides, this enhancement has been prevented in the almost of treated rats compared to solvent and control groups. In hippocampus area, GSH has significantly increased in all treated rats, except for BF and DLT-Que.-treated groups. In striatum, GSH has been depleted in the BF and DLT-treated groups compared to control and solvent groups; in contrast, when Que. was associated with pesticides, the rate of this tripeptide has been maintained at normal levels. In the cortex and cerebellum, GSH has been depleted significantly in all treated animals but has increased in DLT-Que. and mixture-Que.-treated groups in the cerebral cortex, at the same time; it has been maintained at normal levels in BF-Que.-treated groups in the cerebellum compared to control and solvent rats. On the other side, the results of this study have shown a loss of catalase (CAT) and glutathione S-transferase (GST) activities in all brain regions of pesticide-treated rats, but such a fall in enzymatic activities has been prevented by Que. when it was co-administered to rats with pesticides at the dose of 5 mg/kg, except in the cerebellum. In addition, this study has shown mitochondria's swelling in almost all the brain areas with exception of the cerebellum, providing information about a loss of mitochondrial membrane integrity in brain neurons of rats exposed to pyrethrino < ds. Furthermore, preventive administration of Que., in association with pesticides (5 mg/kg) or their mixture (10 mg/kg), has prevented mitochondria swelling in almost all of the analyzed brain tissues.
Показать больше [+] Меньше [-]Modeling technical change in climate analysis: evidence from agricultural crop damages Полный текст
2017
Ahmed, Adeel | Devadason, Evelyn S. | Al-Amin, Abul Quasem
This study accounts for the Hicks neutral technical change in a calibrated model of climate analysis, to identify the optimum level of technical change for addressing climate changes. It demonstrates the reduction to crop damages, the costs to technical change, and the net gains for the adoption of technical change for a climate-sensitive Pakistan economy. The calibrated model assesses the net gains of technical change for the overall economy and at the agriculture-specific level. The study finds that the gains of technical change are overwhelmingly higher than the costs across the agriculture subsectors. The gains and costs following technical change differ substantially for different crops. More importantly, the study finds a cost-effective optimal level of technical change that potentially reduces crop damages to a minimum possible level. The study therefore contends that the climate policy for Pakistan should consider the role of technical change in addressing climate impacts on the agriculture sector.
Показать больше [+] Меньше [-]Efficient removal of antibiotics in a fluidized bed reactor by facile fabricated magnetic powdered activated carbon Полный текст
2017
Ma, Jianqing | Yang, Qunfeng | Xu, Dongmei | Zeng, Xiaomei | Wen, Yuezhong | Liu, Weiping
Powdered activated carbons (PACs) with micrometer size are showing great potential for enabling and improving technologies in water treatment. The critical problem in achieving practical application of PAC involves simple, effective fabrication of magnetic PAC and the design of a feasible reactor that can remove pollutants and recover the adsorbent efficiently. Herein, we show that such materials can be fabricated by the combination of PAC and magnetic Fe₃O₄ with chitosan-Fe hydrogel through a simple co-precipitation method. According to the characterization results, CS–Fe/Fe₃O₄/PAC with different micrometers in size exhibited excellent magnetic properties. The adsorption of tetracycline was fast and efficient, and 99.9% removal was achieved in 30 min. It also possesses good usability and stability to co-existing ions, organics, and different pH values due to its dispersive interaction nature. Finally, the prepared CS–Fe/Fe₃O₄/PAC also performed well in the fluidized bed reactor with electromagnetic separation function. It could be easily separated by applying a magnetic field and was effectively in situ regenerated, indicating a potential of practical application for the removal of pollutants from water.
Показать больше [+] Меньше [-]Effects of pH, initial Pb2+ concentration, and polyculture on lead remediation by three duckweed species Полный текст
2017
Tang, Jie | Chen, Chunxia | Chen, Lei | Daroch, Maurycy | Cui, Yan
Various geographical duckweed isolates have been developed for phytoremediation of lead. The Pb²⁺ removal efficiency of Lemna aequinoctialis, Landoltia punctata, and Spirodela polyrhiza was investigated in monoculture and polyculture at different levels of pH and initial Pb²⁺ concentrations. L. aequinoctialis was not sensitive to the tested pH but significantly affected by initial Pb²⁺ concentration, whereas synergistic effect of pH and initial Pb²⁺ concentration on removal efficiency of L. punctata and S. polyrhiza was found. Although the majority of polycultures showed median removal efficiency as compared to respective monocultures, some of the polycultures achieved higher Pb²⁺ removal efficiencies and can promote population to remove Pb²⁺. Besides, the three duckweed strains could be potential candidates for Pb²⁺ remediation as compared to previous reports. Conclusively, this study provides useful references for future large-scale duckweed phytoremediation.
Показать больше [+] Меньше [-]Impact of highway traffic and the acoustic screen on the content and spatial distribution of heavy metals in soils Полный текст
2017
Różański, Szymon | Jaworska, Hanna | Matuszczak, Katarzyna | Nowak, Joanna | Hardy, Amber
Recent years have witnessed intensification of road traffic and, with it, the amount of substances emitted by vehicles. Such emissions need to be monitored for public health purposes. The aim of this study was to evaluate the impact of the highway traffic on the total content and bioavailability of Zn, Cu, Ni, Cd, Cr and Pb in nearby soils as well as influence of an acoustic screen on spatial distribution of the metals. The material included 40 soil samples collected from 15 research points located 5, 10, 25 and 50 m away from the road acoustic screen and from 4 points between the screen and the highway. Additionally, 5 research points were located next to the metal barrier. Selected physicochemical properties of soils were determined: soil texture, soil pH, TOC and CaCO₃ content. The total content of heavy metals in the soils was determined by AAS after digestion in aqua regia and bioavailable forms in 1 M diethylenetriaminepentaacetic acid. The research found low impact of the highway traffic on the content of heavy metals in soils; however, due to a very short period of this potential impact (5 years), the moderately polluted category of geo-accumulation index of cadmium and high bioavailability of lead indicate the need of repeating the research within the next several years. Furthermore, the road acoustic screen significantly influenced spatial distribution of the metals in soils.
Показать больше [+] Меньше [-]Effects of applying biosolids to soils on the adsorption and bioavailability of 17α-ethinylestradiol and triclosan in wheat plants Полный текст
2017
Cantarero, Romina | Richter, Pablo | Brown, Sally | Ascar, Loreto | Ahumada, Inés
Biosolids contain inorganic and organic contaminants, including pharmaceutical and personal care products (PPCPs) that have accounted for a series of emerging contaminants, such as triclosan (TCS) and the hormone 17α-ethinylestradiol (EE2). The general aim of this study was to evaluate the effects of biosolid application on EE2 and TCS adsorption and bioavailability in soils through testing with wheat plants. For the bioavailability study, sand and two soils, Lampa and Lo Prado, were used. The sand and soils were treated using two biosolid application rates (0 and 90 mg ha⁻¹), and the EE2 and TCS concentrations in the biosolids were determined as 0.54 ± 0.06 and 8.31 ± 0.19 mg kg⁻¹, respectively. The concentration observed in wheat plants indicated that EE2 and TCS are mainly concentrated in the roots rather than in the shoots. Furthermore, the bioavailability of the compounds in plants depends on the properties of the contaminants and the soil. Adsorption studies showed that increasing the soil organic matter content increases the adsorption of TCS and EE2 on these substrates and that both compounds follow the Freundlich adsorption model. The desorption procedure indicated that availability for both TCS and EE2 depended on the soil type because TCS and EE2 were small in the Lampa soil with and without biosolid application and TCS increased by nearly 50% in the Lo Prado soil. The Lo Prado soil had an acidic pH (5.9) and the Lampa soil had a neutral pH of 7.3, and the organic carbon content was smaller.
Показать больше [+] Меньше [-]Efficient solar light-driven degradation of Congo red with novel Cu-loaded Fe3O4@TiO2 nanoparticles Полный текст
2017
Arora, Priya | Fermah, Alisha | Rajput, JaspreetKaur | Singh, Harminder | Badhan, Jigyasa
In this work, Cu-loaded Fe₃O₄@TiO₂ core shell nanoparticles were prepared in a single pot by coating of TiO₂ on Fe₃O₄ nanoparticles followed by Cu loading. X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), thermogravimetric analysis (TGA), Brunauer–Emmett– Teller (BET), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS), and valence band X-ray photoelectron spectroscopy (VB XPS) techniques were used for characterization of as prepared nanoparticles. Synergism between copper and titania was evaluated by studying the solar light-driven photodegradation of Congo red dye solution in the presence of Fe₃O₄@TiO₂ nanoparticles on one side and Cu-loaded Fe₃O₄@TiO₂ nanoparticles on the other side. The latter performed better than the former catalyst, indicating the enhanced activity of copper-loaded catalyst. Further photodegradation was studied by three means, i.e., under ultraviolet (UV), refluxing, and solar radiations. Cu-loaded Fe₃O₄@TiO₂ enhanced the degradation efficiency of Congo red dye. Thus, Cu act possibly by reducing the band gap of TiO₂ and widening the optical response of semiconductor, as a result of which solar light could be used to carry out photocatalysis. Graphical abstract Photodegradation of congo red over Cu-loaded Fe₃O₄@TiO₂ nanoparticles
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