Enlèvement du chrome par infiltration verticale sur lits de Phragmites australis (Cav.) Steudel

L'objectif de la présente étude est de mettre en évidence les potentialités d'un hélophyte : Phragmites australis (Cav.) Steudel à épurer l'effluent du tannage riche en chrome sous un régime d'écoulement vertical et les comparer à celles d'un sol non planté sous climat aride.Le pilote expérimental est constitué de pots de capacité 120 litres, remplis sur une épaisseur de 15 cm de graviers et de 60 cm de sol (texture : limono - argilo- sableuse). Trois pots sont plantés de jeunes tiges de Phragmites australis (36 tiges /m2). Trois autres pots non plantés sont pris comme témoin. L'alimentation du système se fait par l'eau du tannage au chrome diluée à 50%. L’alimentation des systèmes se fait par bâchées de 10 litres/jour pendant 3 jours successifs suivie d’une période de repos de 4 jours. L'écoulement se fait par translation verticale à travers le substrat.L'étude du fonctionnement hydrologique des pilotes testés a montré que le débit moyen à la sortie du système planté est trois fois plus élevé que celui du lit non planté, ce qui permet de traiter un volume d’eau usée plus important ou bien de réduire la superficie nécessaire par équivalent habitant. Aucun signe de colmatage n’a été détecté aussi bien dans les pots plantés de Phragmites australis que dans les pots non plantés.Le suivi des performances épuratoires du système à Phragmites australis montre que le pH à la sortie des deux systèmes pilotes augmente de deux à trois unités par rapport à celui des rejets du tannage. La conductivité électrique des effluents traités augmente respectivement pour les deux systèmes.L’élimination moyenne de la DCO totale est de 74% pour le système planté et de 60,5% pour le système non planté. La différence entre les performances épuratoires des deux systèmes pour l’abattement de la DCO totale est statistiquement significative (p<0,05).Le Cr total subit globalement un abattement de 99% pour les deux pilotes qui fournissent des eaux épurées limpides. En effet, la concentration moyenne en chrome total dans les eaux usées brutes appliquées à l'entrée des différents pilotes varie de 534 mg/l à 1000 mg/l avec une concentration moyenne de 780±196 mg/l. Les teneurs de chrome total enregistrées à la sortie du lit à Phragmites varient de 2,2 mg/l à 3 mg/l avec une concentration moyenne de 2±0,5 mg/l. La concentration en chrome total des eaux usées à la sortie du sol non planté varie de 2,5 mg/l à 4 mg/l avec une valeur moyenne de 2,4±1,3 mg/l.La présence de Phragmites australis dans le système planté permet de maintenir une porosité suffisante pour assurer la percolation des eaux en traitement et réduire les risques de colmatage. Avec des temps de résidence hydraulique trois fois plus réduit, le système planté assure un abattement du chrome total comparable à celui du système non planté.The aim of this study was to investigate the potential of a helophytic plant, Phragmites australis (Cav.) Steudel, to remove chromium from concentrated tannery effluent in comparison to unplanted soil, under arid climate conditions. The experiment was conducted from August 2002 to August 2003. Six plots (capacity: 120 L, diameter: 50 cm) were filled to depths of 15 cm and 60 cm with gravel and soil respectively (texture: 3.5% clay, 8.5% silt, and 88% sand). Three plots were planted with Phragmites australis (Cav.) Steudel. Young shoots of plants (36 stems/m2) were taken from local and natural reed stands. Three unplanted plots were used as controls. The soil for the study was from the Tensift River (Marrakech). The experimental plots were supplied exclusively with diluted tannery wastewater, 3 times a week (approximately 10 L each time). The water flowed vertically through the substratum.To investigate the capacity of the systems to increase pH, to decrease conductivity chemical oxygen demand (COD), and to remove total chromium, concentrations in the inflow and outflow of each plot were determined during the experiment. System hydrology indicated that for planted systems, the mean flow varied from 18 mL/min (in winter) to 49 mL/min (in summer), with an average value of 35 mL/min. For the unplanted system, the mean flow varied from 5 mL/min (in winter) to 15 mL/min (in summer) with an average value of 12 mL/min. Water recovery at the outflow of the planted system (PP) and unplanted system (NPP) was 40% and 60% respectively. This may be related to the phenomenon of evapotranspiration from the PP system, which was more significant than simple evaporation from the NPP system. No sign of clogging was observed in the planted systems due to the plant rhizomes that ensure a better aeration of the soil. The study of the hydrological operation showed that mean flow in the planted system was three times higher than that in the unplanted soil, which makes it possible to treat a larger volume of wastewater and to reduce the required per capita surface for treatment. The presence of Phragmites australis ensured a sufficient porosity for the percolation of water for treatment.The pH of the effluent at the outlets of the planted and unplanted systems increased by two to three units in comparison with the raw wastewater at the inlet. The average inflow pH was 5.5; at the outflow of the two systems, the pH was 7.30 and 8.20 respectively for the planted and unplanted soil. The electrical conductivity (EC) of the treated wastewater increased for the two systems. The average inflow conductivity was 54±5.5ms/cm. At the outflow of the two systems, the EC was about 75±14 ms/cm and 68±11 ms/cm respectively for the planted and unplanted systems. The EC removal for all systems varied significantly from season to another (p< 0.05).The planted system was more efficient in removing total COD (74%) than the unplanted one (61%). There were significant differences (ANOVA) between the PP and NPP systems (p<0.05). Total chromium concentrations at the inflow varied from 534 mg/L to 1000 mg/L with an average content of 780±196 mg/L. At the outflow, total chromium concentrations varied from 2.2 mg/L to 3 mg/L with an average content of 2±0.5 mg/L for the PP system and from 2.5 mg/L to 4 mg/L with an average value of 2.4±1.3 mg/L for the NPP system. Total chromium removal of 99% occurred for the two pilots, which provides limpid purified water. Despite the shorter retention time for the planted system, which was three times less than in the unplanted one, total chromium was almost completely removed.The aquatic macrophyte plant seemed to play a physical role by enhancing the hydrological conductivity of the substratum and consequently the operation and management of these systems. Phragmites australis (Cav.) Steudel has the ability to transfer oxygen from the rhizome towards the roots through an internal lacunar system, which offers the creation of an aerobic zone around the roots. This aerobic zone allows the proliferation of micro-organisms, which are the principal decomposers of the organic matter in the root zone.The treatment of tannery effluent by reed beds is a clean approach from an ecological point of view and constitutes a viable economic alternative in comparison to purely chemical approaches and is thus better adapted to the complexity of the systems used in the leather industry

Effects of CYP3A4*22 and CYP3A5 on clinical outcome in patients treated with ticagrelor for ST-segment elevation myocardial infarction: POPular Genetics sub-study

Aims: To determine the clinical efficacy, adverse events and side-effect dyspnea of CYP3A4*22 and CYP3A5 expressor status in ticagrelor treated patients.Methods and results: Ticagrelor treated patients from the POPular Genetics randomized controlled trial were genotyped for CYP3A4*22 and CYP3A5*3 alleles. Patients were divided based on their genotype. In total 1,281 patients with ST-segment elevation myocardial infarction (STEMI) were included. CYP3A4*22 carriers (n = 152) versus CYP3A4*22 non-carrier status (n = 1,129) were not found to have a significant correlation with the primary thrombotic endpoint: cardiovascular death, myocardial infarction, definite stent thrombosis and stroke [1.3% vs. 2.5%, adjusted hazard ratio 1.81 (0.43–7.62) p = 0.42], or the primary bleeding endpoint: PLATO major and minor bleeding [13.2% vs. 11.3%, adjusted hazard ratio 0.93 (0.58–1.50) p = 0.77]. Among the CYP3A4*1/*1 patients, CYP3A5 expressors (n = 196) versus non-expressors (n = 926) did not show a significant difference for the primary thrombotic [2.6% vs. 2.5%, adjusted hazard ratio 1.03 (0.39–2.71) p = 0.95], or the primary bleeding endpoint [12.8% vs. 10.9%, adjusted hazard ratio 1.13 (0.73–1.76) p = 0.58]. With respect to dyspnea, no significant difference was observed between CYP3A4*22 carriers versus CYP3A4*22 non-carriers [44.0% vs. 45.0%, odds ratio 1.04 (0.45–2.42) p = 0.93], or in the CYP3A4*1/*1 group, CYP3A5 expressors versus CYP3A5 non-expressors [35.3% vs. 47.8%, odds ratio 0.60 (0.27–1.30) p = 0.20].Conclusion: In STEMI patients treated with ticagrelor, neither the CYP3A4*22 carriers, nor the CYP3A5 expressor status had a statistical significant effect on thrombotic and bleeding event rates nor on dyspnea.Clinical Trial Registration:ClinicalTrials.gov, identifier NCT01761786

C3 glomerulopathy-associated CFHR1 mutation alters FHR oligomerization and complement regulation

C3 glomerulopathies (C3G) are a group of severe renal diseases with distinct patterns of glomerular inflammation and C3 deposition caused by complement dysregulation. Here we report the identification of a familial C3G-associated genomic mutation in the gene complement factor H–related 1 (CFHR1), which encodes FHR1. The mutation resulted in the duplication of the N-terminal short consensus repeats (SCRs) that are conserved in FHR2 and FHR5. We determined that native FHR1, FHR2, and FHR5 circulate in plasma as homo- and hetero-oligomeric complexes, the formation of which is likely mediated by the conserved N-terminal domain. In mutant FHR1, duplication of the N-terminal domain resulted in the formation of unusually large multimeric FHR complexes that exhibited increased avidity for the FHR1 ligands C3b, iC3b, and C3dg and enhanced competition with complement factor H (FH) in surface plasmon resonance (SPR) studies and hemolytic assays. These data revealed that FHR1, FHR2, and FHR5 organize a combinatorial repertoire of oligomeric complexes and demonstrated that changes in FHR oligomerization influence the regulation of complement activation. In summary, our identification and characterization of a unique CFHR1 mutation provides insights into the biology of the FHRs and contributes to our understanding of the pathogenic mechanisms underlying C3G

Quantum-sized carbon dots for bright and colorful photoluminescence

通讯作者地址: Sun, YP (通讯作者), Clemson Univ, Dept Chem, Clemson, SC 29634 USA 地址: 1. Clemson Univ, Dept Chem, Clemson, SC 29634 USA 2. Clemson Univ, Lab Emerging Mat & Technol, Clemson, SC 29634 USA 电子邮件地址: [email protected]

Biodégradation de margines par bioréacteur à membrane céramique

National audienceno abstrac

Key process parameters involved in the treatment of olive mill wastewater by membrane bioreactor

International audienceThe Olive Mill Wastewater (OMWW) biodegradation in an external ceramic membrane bioreactor (MBR) was investigated with a starting acclimation step with a Ultrafiltration (UF) membrane (150 kDa) and no sludge discharge in order to develop a specific biomass adapted to OMWW biodegradation. After acclimation step, UF was replaced by an Microfiltration (MF) membrane (0.1 mu m). Sludge Retention Time (SRT) was set around 25 days and Food to Microorganisms ratio (F/M) was fixed at 0.2 kg(COD) kg(MLVSS)(-1) d(-1). At stable state, removal of the main phenolic compounds (hydroxytyrosol and tyrosol) and Chemical Oxygen Demand (COD) were successfully reached (95% both). Considered as a predominant fouling factor, but never quantified in MBR treated OMWW, Soluble Microbial Products (SMP) proteins, polysaccharides and humic substances concentrations were determined (80, 110 and 360 mg L-1 respectively). At the same time, fouling was easily managed due to favourable hydraulic conditions of external ceramic MBR. Therefore, OMWW could be efficiently and durably treated by an MF MBR process under adapted operating parameters