Spectral characterization of the fluorescent components present in humic substances, fulvic acid and humic acid mixed with pure benzo( a )pyrene solution

International audienceThe fate of benzo(a)pyrene (BaP), a ubiquitous contaminant reported to be persistent in the environment, is largely controlled by its interactions with the soil organic matter. In the present study, the spectral characteristics of fluorophores present in the physical fractions of the soil organic matter were investigated in the presence of pure BaP solution. After extraction of humic substances (HSs), and their fractionation into fluvic acid (FA) and humic acid (HA), two fluorescent compounds (C1 and C2) were identified and characterized in each physical soil fraction, by means of fluorescence excitation-emission matrices (FEEMs) and Parallel Factor Analysis (PARAFAC). Then, to each type of fraction having similar DOC content, was added an increasing volume of pure BaP solution in attempt to assess the behavior of BaP with the fluorophores present in each one. The application of FEEMs-PARAFAC method validated a three-component model that consisted of the two resulted fluorophores from HSs, FA and HA (C1 and C2) and a BaP-like fluorophore (C3). Spectral modifications were noted for components C2HSs (C2 in humic substances fraction) (λex/λem: 420/490-520 nm), C2FA (C2 in fulvic acid fraction) (λex/λem: 400/487(517) nm) and C1HA (C1 in humic acid fraction) (λex/λem: 350/452(520) nm). We explored the impact of increasing the volume of the added pure BaP solution on the scores of the fluorophores present in the soil fractions. It was found that the scores of C2HSs, C2FA, and C1HA increased when the volume of the added pure BaP solution increased. Superposition of the excitation spectra of these fluorophores with the emission spectrum of BaP showed significant overlaps that might explain the observed interactions between BaP and the fluorescent compounds present in SOM physical fractions

Life Cycle Assessment of pig production systems of the Noir de Bigorre pork chain

<p>Outdoor pig production systems relying on local pig breeds may cope with environmental and socio-economic challenges of animal production. They produce high quality products with added economic value and mainly rely on local feed resources. </p

Anxiety disorders in 318 bipolar patients : prevalence and impact on illness severity and response to mood stabilizer

International audienc

Mise au point d'un dispositif de collecte d'aérosols nanométriques pour l'analyse biologique

La capacité à détecter et à analyser les particules présentes dans l'air ambiant, et en particulier les particules vivantes, est une préoccupation actuelle majeure. Il est en particulier nécessaire de disposer d'un outil de détection des particules nanométriques présentes dans l'environnement. En effet, le développement récent des nanotechnologies entraîne la production et la dispersion éventuelle de quantité de nanomatériaux. En outre, beaucoup de pathogènes nanométriques peuvent être présents dans l'air, qu'il serait très utile d'être capable de détecter efficacement. Les extracteurs de particules disponibles jusqu'à présent ne sont pas adaptés à ces besoins, puisqu'ils ne sont pas capables de capturer les particules plus petites qu'un micron, qu'ils ne peuvent pas être déplacés ou utilisés de façon autonome, ou encore en raison de leur incapacité à traiter les volumes d'air nécessaires pour une application environnementale

Serotonin transporter gene polymorphism influences age at onset in patients with bipolar affective disorder

International audienc

Evaluation of processing strategies for the manufacturing of Li-ion battery positive electrodes using non-solvent extrusion process

International audienceLithium-ion batteries have known a considerable growth as energy storage devices in portable electronics applications, but also in electrified vehicles and stationary systems over the last few years. Cell manufacturers are looking for technical solutions to further reduce the costs of production lines. One of the critical steps is the production of positive and negative electrodes, i.e. the preparation of slurries and coating on current collectors. These complex stages involve the use of solvents that have to be removed during an energy-consuming drying phase. This is of particular importance for the production of positive electrodes where state-of-the-art industrial process is based on the use of carcinogenic N-methyl-2-pyrrolidone (NMP) solvent, which implies the use of safety protocols and equipment for solvent recovery and recycling.Alternatives to this conventional manufacturing route have been proposed such as extrusion, a well-known process in the plastics industry. Extrusion allows to work with viscous matrices by combining the mixing (homogenisation, dispersion) and film forming (flat die extrusion, lamination) in a continuous way. Generally, the use of solvents is very limited or even eliminated, which makes it an innovative process compared to the standard one. Its industrialisation in the field of batteries therefore seems to be relevant because it combines a continuous process, a small footprint and limited costs.Here we report the evaluation of two different strategies for the production of porous cathodes for Li-ion batteries without the need of NMP. In one hand, the use of small amount of water in the electrode composition is evaluated and its impact on battery lifetime is characterized. On the other hand, solid blowing agents are directly added in the formulation to create pores by thermally activated decomposition reactions. The impact of these new processes on the electrode morphology is thoroughly characterized with the help of scanning electronic microscope, helium pycnometer and mercury intrusion porosimeter. Electrochemical performances of promising samples are evaluated after assembly of coin and pouch cells. Finally, optimization routes are proposed toward energy-saving and dry processes for electrode manufacturing

Evaluation of processing strategies for the manufacturing of Li-ion battery positive electrodes using non-solvent extrusion process

International audienceLithium-ion batteries have known a considerable growth as energy storage devices in portable electronics applications, but also in electrified vehicles and stationary systems over the last few years. Cell manufacturers are looking for technical solutions to further reduce the costs of production lines. One of the critical steps is the production of positive and negative electrodes, i.e. the preparation of slurries and coating on current collectors. These complex stages involve the use of solvents that have to be removed during an energy-consuming drying phase. This is of particular importance for the production of positive electrodes where state-of-the-art industrial process is based on the use of carcinogenic N-methyl-2-pyrrolidone (NMP) solvent, which implies the use of safety protocols and equipment for solvent recovery and recycling.Alternatives to this conventional manufacturing route have been proposed such as extrusion, a well-known process in the plastics industry. Extrusion allows to work with viscous matrices by combining the mixing (homogenisation, dispersion) and film forming (flat die extrusion, lamination) in a continuous way. Generally, the use of solvents is very limited or even eliminated, which makes it an innovative process compared to the standard one. Its industrialisation in the field of batteries therefore seems to be relevant because it combines a continuous process, a small footprint and limited costs.Here we report the evaluation of two different strategies for the production of porous cathodes for Li-ion batteries without the need of NMP. In one hand, the use of small amount of water in the electrode composition is evaluated and its impact on battery lifetime is characterized. On the other hand, solid blowing agents are directly added in the formulation to create pores by thermally activated decomposition reactions. The impact of these new processes on the electrode morphology is thoroughly characterized with the help of scanning electronic microscope, helium pycnometer and mercury intrusion porosimeter. Electrochemical performances of promising samples are evaluated after assembly of coin and pouch cells. Finally, optimization routes are proposed toward energy-saving and dry processes for electrode manufacturing

Long-term correction of ornithine transcarbamylase deficiency in Spf-Ash mice with a translationally optimized AAV vector

International audienceOrnithine transcarbamylase deficiency (OTCD) is an X-linkedliver disorder caused by partial or total loss of OTC enzymeactivity. It is characterized by elevated plasma ammonia, leadingto neurological impairments, coma, and death in the most severecases. OTCD is managed by combining dietary restrictions, essen-tial amino acids, and ammonia scavengers. However, to date, livertransplantation provides thebest therapeutic outcome. AAV-mediated gene-replacement therapy represents a promising cura-tive strategy. Here, we generated an AAV2/8 vector expressing acodon-optimized humanOTCcDNA by thea1-AATliver-specificpromoter. Unlike standard codon-optimization approaches, weperformed multiple codon-optimization rounds via common al-gorithms and ortholog sequence analysis that significantlyimproved mRNA translatability and therapeutic efficacy.AAV8-hOTC-CO (codon optimized) vector injection into adultOTCSpf-Ashmice (5.0E11 vg/kg) mediated long-term completecorrection of the phenotype. Adeno-Associated viral (AAV) vec-tor treatment restored the physiological ammonia detoxificationliver function, as indicated by urinary orotic acid normalizationand by conferring full protection against an ammonia challenge.Removal of liver-specific transcription factor binding sites fromthe AAV backbone did not affect gene expression levels, with a po-tential improvement in safety. These results demonstrate thatAAV8-hOTC-CO gene transfer is safe and results in sustainedcorrection of OTCD in mice, supporting the translation of thisapproach to the clinic