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An investigation of the well-water quality: immunosensor for pathogenic Pseudomonas aeruginosa detection based on antibody-modified poly(pyrrole-3 carboxylic acid) screen-printed carbon electrode النص الكامل
2015
Bekir, Karima | Bousimma, Feriel | Barhoumi, Houcine | Fedhila, Kais | Maaref, Abderrazak | Bakhrouf, Amina | Ouada, Hafedh Ben | Namour, Philippe | Jaffrezic-Renault, N. (Nicole) | Mansour, Hedi Ben
An investigation of the well-water quality: immunosensor for pathogenic Pseudomonas aeruginosa detection based on antibody-modified poly(pyrrole-3 carboxylic acid) screen-printed carbon electrode النص الكامل
2015
Bekir, Karima | Bousimma, Feriel | Barhoumi, Houcine | Fedhila, Kais | Maaref, Abderrazak | Bakhrouf, Amina | Ouada, Hafedh Ben | Namour, Philippe | Jaffrezic-Renault, N. (Nicole) | Mansour, Hedi Ben
In this report, we describe a new immunosensor designed for the detection and the quantification of Pseudomonas aeruginosa bacteria in water. The developed biosensing system was based on the immobilization of purified polyclonal anti P. aeruginosa antibodies on electropolymerized poly(pyrrole-3-carboxylic acid)/glassy carbon electrode. The building of the immunosensor step by step was evaluated by electrochemical measurements such as cyclic voltammetry (CV) and impedance spectroscopy (EIS). The electrochemical signature of the immunosensor was established by the change of the charge transfer resistance when the bacteria suspended in solution became attached to the immobilized antibodies. As a result, stable and high sensitive impedimetric immunosensor was obtained with a sensitivity of 0.19 kΩ/decade defined in the linear range from 10¹ to 10⁷ CFU/mL of cellular concentrations. A low detection limit was obtained for the P. aeruginosa bacteria and a high selectivity when other bacteria were occasioned as well as Escherichia coli. The developed immunosensor was applied in detecting pathogenic P. aeruginosa in well-water.
اظهر المزيد [+] اقل [-]An investigation of the well-water quality: immunosensor for pathogenic Pseudomonas aeruginosa detection based on antibody-modified poly(pyrrole-3 carboxylic acid) screen-printed carbon electrode النص الكامل
2015
Bekir, Karima | Bousimma, Feriel | Barhoumi, Houcine | Fedhila, Kais | Maaref, Abderrazak | Bakhrouf, Amina | Ben Ouada, Hafedh | Namour, Philippe | Jaffrezic-Renault, Nicole | Ben Mansour, Hedi | Laboratoire d’analyse, de traitement et de valorisation des polluants de l’environnement et des produits [Monastir] (LATVPEP) ; Faculté de Pharmacie [Monastir] (FPHM) | Laboratoire des Interfaces et Matériaux Avancés [Monastir] (LIMA) ; Faculté des Sciences de Monastir (FSM) ; جامعة المنستير - Université de Monastir - University of Monastir (UM)-جامعة المنستير - Université de Monastir - University of Monastir (UM) | Res Unit, Anal & Proc Appl Environm ; جامعة المنستير - Université de Monastir - University of Monastir (UM) | Milieux aquatiques, écologie et pollutions (UR MALY) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | River Monitoring & Management - Suivi et gestion des rivières (2014-2016) ; Institut des Sciences Analytiques (ISA) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | ISA-Interfaces & biosensors - Interfaces & biocapteurs ; Institut des Sciences Analytiques (ISA) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS)
[Departement_IRSTEA]Eaux | International audience | In this report, we describe a new immunosensor designed for the detection and the quantification of Pseudomonas aeruginosa bacteria in water. The developed biosensing system was based on the immobilization of purified polyclonal anti P. aeruginosa antibodies on electropolymerized poly(pyrrole-3-carboxylic acid)/glassy carbon electrode. The building of the immunosensor step by step was evaluated by electrochemical measurements such as cyclic voltammetry (CV) and impedance spectroscopy (EIS). The electrochemical signature of the immunosensor was established by the change of the charge transfer resistance when the bacteria suspended in solution became attached to the immobilized antibodies. As a result, stable and high sensitive impedimetric immunosensor was obtained with a sensitivity of 0.19 k Omega/decade defined in the linear range from 10(1) to 10(7) CFU/mL of cellular concentrations. A low detection limit was obtained for the P. aeruginosa bacteria and a high selectivity when other bacteria were occasioned as well as Escherichia coli. The developed immunosensor was applied in detecting pathogenic P. aeruginosa in well-water.
اظهر المزيد [+] اقل [-]IgE antibodies and urinary trimethylarsine oxide accounted for 1–7 % population attributable risks for eczema in adults: USA NHANES 2005–2006 النص الكامل
2015
Shiue, Ivy
Population attributable risks from serum IgE and dust miteallergen concentrations and environmental chemicals for eczema are unclear. Therefore, it was aimed to examine serum IgE and allergen concentrations and environmental chemicals for eczema in adults and to calculate population attributable risks in a national and population-based setting. Data retrieved from the National Health and Nutrition Examination Survey, 2005–2006, was analyzed. Information on demographics and self-reported ever eczema was obtained by household interview. Bloods and urines (sub-sample) were also collected during the interview. Adults aged 20–85 were included. Statistical analyses were using chi-square test, t test, survey-weighted logistic regression modeling, and population attributable risk (PAR) estimation. Of all the included American adults (n = 4979), 310 (6.2 %) reported ever eczema. Moreover, more eczema cases were observed in female adults but fewer cases in people born in Mexico. There were no significant associations observed between commonly known biomarkers (including vitamin D) and eczema or between dust mite allergens and eczema. Serum D. Farinae (PAR 1.0 %), D. Pteronyssinus (PAR 1.1 %), cat (PAR 1.8 %), dog (PAR 1.6 %), and muse (PAR 3.2 %) IgE antibodies were associated with eczema. Adults with ever eczema were found to have higher levels of urinary trimethylarsine oxide concentrations (PAR 7.0 %) but not other speciated arsenic concentrations. There were no clear associations between other environmental chemicals including heavy metals, phthalates, phenols, parabens, pesticides, nitrate, perchlorate, polycyclic hydrocarbons and eczema as well. Elimination of environmental risks might help delay or stop eczema up to 7 % in the adult population.
اظهر المزيد [+] اقل [-]Study on the release routes of allelochemicals from Pistia stratiotes Linn., and its anti-cyanobacteria mechanisms on Microcystis aeruginosa النص الكامل
2015
Wu, Xiang | Wu, Hao | Ye, Jinyun | Zhong, Bin
Allelochemicals in Pistia stratiotes Linn. have a strong anti-cyanobacteria effect on Microcystis aeruginosa. To further determine the release routes of allelochemicals in P. stratiotes and understand their anti-cyanobacteria mechanisms, we aimed to systematically investigate the allelopathic effects of leaf leachates, leaf volatilization, root exudates, and residue decomposition of P. stratiotes on M. aeruginosa. The influences of P. stratiotes allelochemicals on the physiological properties of M. aeruginosa were also studied. Root exudates of P. stratiotes exhibited the strongest inhibitory effect on M. aeruginosa growth. The residue decomposition and leaf leachates exhibited a relatively strong inhibitory effect on M. aeruginosa growth. By contrast, the leaf volatilization stimulated M. aeruginosa growth. Therefore, root exudation was determined to be the main release route of allelochemicals from P. stratiotes. The mixed culture experiment of P. stratiotes root exudates and M. aeruginosa showed that the allelochemicals released from root exudation had no effect on the electron transfer of M. aeruginosa photosynthetic system II. However, it reduced the phycocyanin (PC) content and phycocyanin to allophycocyanin (PC/APC) ratio in the photosynthetic system. As the root exudates concentration increased, the electrical conductivity (EC) and superoxide anion radical (O₂ *⁻) values in the M. aeruginosa culture fluid increased significantly, indicating that the allelochemicals released from the root of P. stratiotes inhibited algae growth by affecting the PC and PC/APC levels in photosynthesis, destroying the cell membrane, and increasing O₂ *⁻ content to result in oxidative damage of M. aeruginosa.
اظهر المزيد [+] اقل [-]Energy analyses and greenhouse gas emissions assessment for saffron production cycle النص الكامل
2015
Bakhtiari, Amir Abbas | Hematian, Amir | Sharifi, Azin
Population growth and world climate changes are putting high pressure on agri-food production systems. Exacerbating use of energy sources and expanding the environmental damaging symptoms are the results of these difficult situations. This study was conducted to determine the energy balance for saffron production cycle and investigate the corresponding greenhouse gas (GHG) emissions in Iran. Saffron (Crocus sativus L.) is one of the main spice that historically cultivated in Iran. Data were obtained from 127 randomly selected saffron growers using a face to face questionnaire technique. The results revealed that in 5 years of saffron production cycle, the overall input and output energy use were to be 163,912.09 and 184,868.28 MJ ha⁻¹, respectively. The highest-level of energy consumption belongs to seeds (23.7 %) followed by chemical fertilizers (23.4 %). Energy use efficiency, specific energy, net energy, and energy productivity of saffron production were 1.1, 13.4 MJ kg⁻¹, 20,956.2 MJ ha⁻¹, and 0.1 kg MJ⁻¹, respectively. The result shows that the cultivation of saffron emits 2325.5 kg CO₂ eq. ha⁻¹ greenhouse gas, in which around 46.5 % belonged to electricity followed by chemical fertilizers. In addition the Cobb-Douglas production function was applied into EViews 7 software to define the functional relationship. The results of econometric model estimation showed that the impact of human labor, electricity, and water for irrigation on stigma, human labor, electricity, and seed on corm and also human labor and farmyard manure (FYM) on flower and leaf yield were found to be statistically significant. Sensitivity analysis results of the energy inputs demonstrated that the marginal physical productivity (MPP) worth of electricity energy was the highest for saffron stigma and corm, although saffron flower and leaf had more sensitivity on chemicals energy inputs. Moreover, MPP values of renewable and indirect energies were higher than non-renewable and direct energies, respectively.
اظهر المزيد [+] اقل [-]Harmful algal bloom removal and eutrophic water remediation by commercial nontoxic polyamine-co-polymeric ferric sulfate-modified soils النص الكامل
2015
Dai, Guofei | Zhong, Jiayou | Song, Lirong | Guo, Chunjing | Gan, Nanqin | Wu, Zhenbin
Harmful algal bloom has posed great threat to drinking water safety worldwide. In this study, soils were combined with commercial nontoxic polyamine poly(epichlorohydrin–dimethylamine) (PN) and polymeric ferric sulfate (PFS) to obtain PN-PFS soils for Microcystis removal and eutrophic water remediation under static laboratory conditions. High pH and temperature in water could enhance the function of PN-PFS soil. Algal removal efficiency increased as soil particle size decreased or modified soil dose increased. Other pollutants or chemicals (such as C, P, and organic matter) in eutrophic water could participate and promote algal removal by PN-PFS soil; these pollutants were also flocculated. During PN-PFS soil application in blooming field samples, the removal efficiency of blooming Microcystis cells exceeded 99 %, the cyanotoxin microcystins reduced by 57 %. Water parameters (as TP, TN, SS, and SPC) decreased by about 90 %. CODMₙ, PO₄-P, and NH₄-N also sharply decreased by >45 %. DO and ORP in water improved. Netting and bridging effects through electrostatic attraction and complexation reaction could be the two key mechanisms of Microcystis flocculation and pollutant purification. Considering the low cost of PN-PFS soil and its nontoxic effect on the environment, we proposed that this soil combination could be applied to remove cyanobacterial bloom and remediate eutrophic water in fields.
اظهر المزيد [+] اقل [-]Adsorption and desorption characteristics of methamphetamine, 3,4-methylenedioxymethamphetamine, and pseudoephedrine in soils النص الكامل
2015
Pal, Raktim | Megharaj, Mallavarapu | Kirkbride, K Paul | Naidu, R.
This work presents, for the first time, information on the adsorption–desorption characteristics of illicit drugs and precursors in soils and an estimation of their potential bioavailability. The experiment was conducted using a batch equilibrium technique for the parent drugs methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA) and the precursor pseudoephedrine in three South Australian soils varying in physiochemical properties. The individual compounds exhibited different adsorption mechanisms in the test soils, and the results fitted better with the Freundlich isotherm model (r ² ≥ 0.99). The maximum adsorption capacity was recorded for pseudoephedrine (2,000 μg g⁻¹). However, pseudoephedrine recorded lower organic carbon normalized adsorption coefficient values (<250 mL g⁻¹), lower magnitudes of Gibb’s free energy change, and higher percent desorption (73–92 %) compared to methamphetamine and MDMA. The results thus showed pseudoephedrine to be the most mobile compound in the soils under study, to have the highest availability for degradation of the three compounds, and to have the highest susceptibility to biotic degradation in test soils.
اظهر المزيد [+] اقل [-]Contamination of nitrate in groundwater and its potential human health: a case study of lower Mae Klong river basin, Thailand النص الكامل
2015
Wongsanit, Jaturong | Teartisup, Piyakarn | Kerdsueb, Prapeut | Tharnpoophasiam, Prapin | Worakhunpiset, Suwalee
Nitrate contamination in groundwater is a worldwide problem especially in agricultural countries. Environmental factors, such as land-use pattern, type of aquifer, and soil-drainage capacity, affect the level of contamination. Exposure to high levels of nitrate in groundwater may contribute to adverse health effects among residents who use groundwater for consumption. This study aimed to determine the relationship between nitrate levels in groundwater with land-use pattern, type of aquifer, and soil-drainage capacity, in Photharam District, Ratchaburi Province, lower Mae Klong basin, Thailand. Health risk maps were created based on hazard quotient to quantify the potential health risk of the residents using US Environmental Protection Agency (U.S. EPA) health risk assessment model. The results showed the influence of land-use patterns, type of aquifer, and soil-drainage capacity on nitrate contamination. It was found that most of the residents in the studied area were not at risk; however, a groundwater nitrate monitoring system should be implemented.
اظهر المزيد [+] اقل [-]Basin-scale emission and multimedia fate of triclosan in whole China النص الكامل
2015
Zhang, Qian-Qian | Ying, Guang-Guo | Chen, Zhi-Feng | Zhao, Jian-Liang | Liu, You-Sheng
This study aimed to investigate the emission and multimedia fate as well as potential risks of triclosan (TCS) in all of 58 basins in China. The results showed that the total usage of TCS in whole China was 100 t/year, and the discharge to the receiving environment was estimated to be 66.1 t/year. The predicted TCS concentrations by the level III fugacity model were within an order of magnitude of the reported measured concentrations. TCS (90.8 %) was discharged into the water compartment and 9.2 % to the soil compartment. The TCS concentration levels in east China were found generally higher than in west China. In addition, the input flux for TCS to seawater was largely attributed to the seasonal variations in advection flows. Preliminary risk assessment showed that medium to high ecological risks for TCS would be expected in the eastern part of China due to the high population density.
اظهر المزيد [+] اقل [-]Results of the clean-up operation to reduce pollution on flooded agricultural fields after the red mud spill in Hungary النص الكامل
2015
Uzinger, Nikolett | Anton, Áron Dániel | Ötvös, Károly | Tamás, Péter | Anton, Attila
In Hungary, the dam of a red mud reservoir breached shortly after noon on October 4, 2010. Approximately 0.7–1 million m³ highly alkaline red mud with very low dry matter content flowed into the Torna Creek and the surrounding area, covering 1017 ha of agricultural land. Results of the risk assessment of the accident indicated that the red mud should be removed from the surface of fields where it formed a continuous layer of more than 5 cm. After the removal, samples were taken manually from depths of 0.0–0.2 m and 0.2–0.4 m in a sampling grid and background samples unaffected by red mud from the depth of 0.0–0.3 m. Total element contents (Ag, As, Ba, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sn, Zn, and Na) and pH values were measured, and the results were analysed using correlation analysis and the Kruskal–Wallis probe. Dependence of the measured variables from elevation above sea level was studied using a 10 m by 10 m digital elevation model. Only ∼6.5 % of the flooded area was temporarily designated as unsuitable for the production of food and fodder crops. In summary, the clean-up operation can be said to have been a success.
اظهر المزيد [+] اقل [-]Polycyclic aromatic hydrocarbons in the largest deepwater port of East China Sea: impact of port construction and operation النص الكامل
2015
Li, Juan-Ying | Cui, Yu | Su, Lei | Chen, Yiqin | Jin, Ling
PAHs were analyzed for samples of seawater, sediment, and oyster (Saccostrea cucullata) collected from Yangshan Port, East China between 2012 and 2013. Concentrations of ∑PAHs in seawater (180–7,700 ng/L) and oyster (1,100–29,000 ng/g dry weight (dw)) fell at the higher end of the global concentration range, while sediment concentrations (120–780 ng/g dw) were generally comparable to or lower than those reported elsewhere. PAHs in the particulate phase accounted for 85 % (52–93 %) of the total PAHs in seawater. Congener profile analysis revealed that PAHs in waters originate mainly from petrogenic sources, while high-temperature combustion processes are the predominant sources for sediment. ∑PAHs in oyster well correlated with ∑PAHs in the particulate phase, suggesting particle ingestion as an important pathway for bioaccumulation of PAHs. Cancer risk assessment of PAHs in oyster indicated high human health risks posed by these chemicals to the coastal population consuming this seafood.
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