97 research outputs found
Evaluation de la tenue du partogramme dans une maternité universitaire
Introduction: La mortalité maternelle est un problème majeur de santé mondiale. Une grande proportion de ces décès serait évitable par des soins adéquats, une aide à l'accouchement, la disponibilité des soins d'urgence et l'utilisation des outils d'aide à la décision tels que le partogramme. L'objectif était d'évaluer l'écart entre ce qui est censé être fait et ce qui est fait réellement pour les différents paramètres situés dans le partogramme au sein d'une maternité de 3ème niveau et élaborer des recommandations pour la mise en place d'un plan d'action. Méthodes: Il s'agit d'une étude descriptive rétrospective par audit clinique, effectuée sur un échantillon de 400 dossiers obstétricaux des parturientes ayant accouchées dans la maternité du CHU Farhat Hached durant l'année 2011. Le référentiel utilisé est celui réalisé par l'Agence Nationale d'Accréditation et d'Evaluation en Santé en l'an 2000, concernant la qualité de la tenue du partogramme. Résultats: La majorité des critères d'évaluation portant sur la présentation du partogramme était conforme. Deux critères concernant la variété de la présentation et le rythme cardiaque foetal étaient non conformes parmi ceux portant sur la surveillance du foetus. Plusieurs critères en rapport avec la surveillance de la mère étaient non conformes. Aucun des critères portant sur les traitements administrés et les marqueurs d'évènements n'est conforme. Les critères portant sur la naissance et la surveillance immédiate qui étaient non conformes sont : le début des efforts expulsifs, le mode d'accouchement, l'état du périnée, la délivrance et la révision utérine. Conclusion: La véritable démarche de l'audit clinique se doit d'aller au-delà du recueil et de l'analyse des données, le but final étant l'amélioration des pratiques
KSHV gB associated RGD interactions promote attachment of cells by inhibiting the potential migratory signals induced by the disintegrin-like domain
Background: Kaposi's sarcoma-associated herpesvirus (KSHV) glycoprotein B (gB) is not only expressed on the envelope of mature virions but also on the surfaces of cells undergoing lytic replication. Among herpesviruses, KSHV gB is the only glycoprotein known to possess the RGD (Arg-Gly-Asp) binding integrin domain critical to mediating cell attachment. Recent studies described gB to also possess a disintegrin-like domain (DLD) said to interact with non-RGD binding integrins. We wanted to decipher the roles of two individually distinct integrin binding domains (RGD versus DLD) within KSHV gB in regulating attachment of cells over cell migration
Genomic insights into members of the candidate phylum Hyd24-12 common in mesophilic anaerobic digesters
Members of the candidate phylum Hyd24-12 are globally distributed, but no genomic information or knowledge about their morphology, physiology or ecology is available. In this study, members of the Hyd24-12 lineage were shown to be present and abundant in full-scale mesophilic anaerobic digesters at Danish wastewater treatment facilities. In some samples, a member of the Hyd24-12 lineage was one of the most abundant genus-level bacterial taxa, accounting for up to 8% of the bacterial biomass. Three closely related and near-complete genomes were retrieved using metagenome sequencing of full-scale anaerobic digesters. Genome annotation and metabolic reconstruction showed that they are Gram-negative bacteria likely involved in acidogenesis, producing acetate and hydrogen from fermentation of sugars, and may play a role in the cycling of sulphur in the digesters. Fluorescence in situ hybridization revealed single rod-shaped cells dispersed within the flocs. The genomic information forms a foundation for a more detailed understanding of their role in anaerobic digestion and provides the first insight into a hitherto undescribed branch in the tree of life
The microbial community structure in industrial biogas plants influences the degradation rate of straw and cellulose in batch tests
Trace organic contaminants in biosolids: Impact of conventional wastewater and sludge processing technologies and emerging alternatives
Étude de la dégradation des micropolluants organiques au cours de la digestion anaérobie des déchets non dangereux : approche moléculaire et isotopique
The study consists in choosing and developing a methodology to realize anaerobic biodegradation experiments of different organic micro pollutants belonging to the class of phenolic compounds frequently found in non dangerous waste. The first step was the development of an analytical protocol allowing the simultaneous analysis of a group of compounds: phenol, methylphenols, chlorophenols and bisphenol-A. This protocol can be adapted for the specific analysis of each one of these types of compounds. After having carried out household waste degradation microcosms in anaerobe under the mesophilic (35 °C) and thermophilic (55 °C) conditions, we followed the production of biogas until obtaining a stable methanogenesis; at this stage we add each of the fully carbon 13 enriched micro pollutants in a microcosm. We then decided to study the biodegradation of these marked molecules thanks to an original approach combining isotopic tracing with molecular analyses, in order to validate the results of degradation by comparing the results obtained with those existing in the literature. We thus could highlight that phenol was mineralized both in mesophilic and thermophilic conditions but by different metabolic pathways thanks to the degradation products identification. In the case of bisphenol-A, an important adsorption of this compound on the solid matrix and a complete absence of mineralization at the same time at 35°C and 55°C were revealed. Finally, in the case of chlorophenols (2,4,6-trichlorophenol and pentachlorophenol) we observed a beginning of degradation of these compounds in mesophilic conditions but the mineralization was partial because one of the breakdown products, 4-chlorophenol, persists and doesn’t seem degradable under these conditions. Under thermophilic conditions no chlorophenols degradation was observed.Les travaux effectués dans le cadre de cette thèse ont pour objectif d’étudier la biodégradation durant la digestion anaérobie des déchets de différents micropolluants organiques appartenant à la classe des composés phénoliques fréquemment rencontrés dans les déchets non dangereux. La première étape a consisté en la mise au point d’un protocole analytique permettant l’analyse simultanée d’un ensemble de composés: phénol, méthylphénols, chlorophénols et bisphénol-A. Ce protocole peut être adapté pour l’analyse spécifique de chacun de ces types de composés. Après avoir réalisé des microcosmes de dégradation de déchets ménagers en anaérobiose en conditions mésophiles (35 °C) et thermophiles (55 °C), un suivi de la production de biogaz a été effectué jusqu’à l’obtention d’une méthanogenèse stable. A ce stade un ajout de chaque micropolluant marqué en carbone 13 a été réalisé dans chacun des microcosmes. La biodégradation de ces molécules a été étudiée grâce à une approche originale combinant le traçage isotopique aux analyses moléculaires permettant de mettre en évidence la minéralisation et d’identifier les produits de dégradation des composés étudiés. Il a ainsi été possible de mettre en évidence que le phénol était minéralisé à la fois en condition mésophile et thermophile mais par des voies métaboliques différentes grâce à l'identification des produits de dégradation. Dans le cas du bisphenol A, une adsorption importante de ce composé sur la matrice solide et une absence totale de minéralisation à la fois à 35 °C et 55 °C ont été mises en évidence. Enfin, dans le cas des chlorophénols (2,4,6-trichlorophénol et pentachlorophénol) un début de dégradation de ces composés en condition mésophile a été observé qui reste partielle car l'un des produits de dégradation, le 4-chlorophénol, persiste et ne semble pas dégradable dans ces conditions. En condition thermophile aucune dégradation des chlorophénols n'a été observée
Off-line solid-phase extraction procedure for the determination of polycyclic aromatic hydrocarbons from aqueous matrices
An off-line solid-phase extraction procedure followed by
High-performance Liquid Chromatography with Ultraviolet detection for
the determination of 16 priority polycyclic aromatic hydrocarbons
pollutants in aqueous matrices was described. Diverse aspects
determining extraction efficiency such as packing type (disk or
cartridge); elution solvents and addition of organic modifiers to the
sample were evaluated. Elution with acetonitrile yields the highest
recoveries. Rinsing the sample bottle with acetonitrile and combining
the rinse with the sample extract avoids the adsorption of polycyclic
aromatic hydrocarbons on the walls of the water containers. The use of
isopropanol or methanol 10% (V/V) was the most appropriate amount for
the enrichment of 2-6 ring aromatic compounds only on C18 cartridge.
The recoveries for all studied polycyclic aromatic hydrocarbons are
ranged from 71.4 to 95.2% for a treated water samples of 500 mL. The
proposed method gives very low detection limits (subnanograms per
liter) and it has been applied to drinking water, surface water and
industrial effluent (oil refinery) samples with good results
Biodégradation du Penta- et 2,4,6-tri-chlorophenol durant la digestion anaérobie des déchets non dangereux
International audienceIn this study isotopic tracing using C-13 labelled pentachlorophenol (PCP) and 2,4,6-trichlorophenol (2,4,6-TCP) is proposed as a tool to distinguish the loss of PCP and 2,4,6-TCP due to biodegradation from other physical processes. This isotopic approach was applied to accurately assess in situ PCP and 2,4,6-TCP degradation under methanogenic conditions in several microcosms made up of household waste. These microcosms were incubated in anaerobic conditions at 35 degrees C (mesophilic) and 55 degrees C (thermophilic) without agitation. The volume of biogas produced (CH4 and CO2), was followed for a period of 130 days. At this stage of stable methanogenesis, C-13(6)-PCP and C-13(6)-2,4,6-TCP were introduced anaerobically in microcosms and its monitoring at mesophilic and thermophilic conditions was performed in parallel by gas chromatography mass spectrometry (GC-MS) and gas chromatography isotope-ratio mass spectrometry (GC-IRMS). This study proved the almost total dechlorination of bioavailable PCP and 2,4,6-TCP into 4-CP at 35 degrees C. Nevertheless, high rate adsorption in particular materials of the two compounds was observed. Furthermore, Carbon-13 Nuclear Magnetic Resonance (C-13-NMR) Spectroscopy analysis of C-13 labelled 2,4,6-TCP mesophilic incubations showed the partial mineralization of 4-CP at 35 degrees C to acetate and then to HCO3-. Consequently, NMR results confirm the biogas isotopic results indicating the mineralization of C-13 labelled 2,4,6-TCP into C-13 (CH4 and CO2). Concerning C-13 labelled PCP mesophilic incubations, the isotopic composition of the biogas still natural until the day 262. In contrast, no de chlorination was observed at 55 degrees C. Thus PCP and 2,4,6-TCP were persistent in thermophilic conditions
Analyse de fiabilité d'une structure de protection en béton armé sollicitée par un signal de pression caractéristique d'une avalanche de neige dense
International audienceTo protect humans, roads or houses against snow avalanches, civil engineering structures are widely used. Designing these structures is still a challenge especially due to the uncertainties related to the loading developed by a snow avalanche. The case of the avalanche of Taconnaz (France), which occurred in 1999 and where important parts of the RC defense structure were destroyed, underlines the necessary to consider reliability approaches for the design of such structures. This paper proposes a reliability analysis of an L-shaped reinforced concrete (RC) protective structure subjected to a dense snow avalanche. A deterministic mechanical model, based on the finite element method, has been developed and allows describing the behavior of the structure. Next, a reliable model allows propagating uncertainties through the mechanical model and assessing the failure probability of the structure. The choices of random variables (the inputs) and their distributions, the failure criteria and the reliability methods are presented and discussed. Two criteria are considered: on the one hand, a local criterion defined in term of stress exceedence within concrete and steel, and on the other hand a global criterion defined in term of maximal displacement of the structure. Moreover, Kernel Smoothing and Monte-Carlo methods are used and compared to assess the failure probability and to derive fragility curves. These latter describe the failure probability of the structure according to the loading magnitude
Simultaneous determination of phenol, methylphenols, chlorophenols and bisphenol-A by headspace solid-phase microextraction-gas chromatography-mass spectrometry in water samples and industrial effluents
International audienceA headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) automatic method for simultaneous determination of trace amounts of phenol, methylphenols (MPs), chlorophenols (CPs) and bisphenol-A (BPA) in water samples and industrial effluents has been developed. Prior to SPME extraction, a direct derivatisation step using acetic anhydride was performed. Four different SPME fibre coatings (75 mm CAR-PDMS, 65 mm PDMS-DVB, 100 mm PDMS and 85 mm PA) were tested. The parameters affecting the HS-SPME process and derivatisation step studied were: extraction time (560 min) and temperature (40100C), derivatisation time (510 min), sample agitation (0500 rpm), addition of sodium chloride (040%). The GC-MS quantification was performed by internal standard calibration and the limits of detection (LODs) were in the low ng L1. The proposed analytical procedure provided a good linearity (r240.9931) for standard solutions and a repeatability ranging from 4.8 to 15.2% (nÂĽ5). The obtained results show that the developed method was rapid, simple and efficient for phenol, MPs, CPs and BPA analysis, and provides a good alternative to SPE and LLE. Finally, the proposed method has been applied successfully to analyse water samples, municipal solid waste landfill and industrial effluents
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