Résultats à moyen terme du traitement des ostéochondrites disséquantes des condyles fémoraux par greffe ostéochondrale en mosaïque

Face à une perte de substance cartilagineuse des condyles fémoraux, plusieurs alternatives thérapeutiques interventionnelles sont envisageables y compris la mosaïcoplastie. Le but de notre travail était d'évaluer le résultat clinique et radiologique à moyen terme ainsi que d'évaluer les principaux éléments pronostiques. Notre étude épidémiologique rétrospective étalée sur 15 ans nous a permis de colliger 35 dossiers exploitables d'ostéochondrite disséquante des condyles fémoraux traités par la technique de mosaïcoplastie avec un recul moyen de 24 mois. Le niveau des plaintes ainsi que la fonction du genou en préopératoire ont été étudiés et comparés par rapport au genou sain selon le Score International Cartilage Repair Society (ICRS), le score International Knee Documentation Committee (IKDC) et l'échelle visuelle de la douleur (EVA) et nous avons trouvé qu'elle était inférieure à 60% chez 27 malades. L'évaluation des résultats au recul ont été analysés selon les critères fonctionnels et radiologiques de Hunghston. Après un recul moyen de 24 mois, l'algoneurodystrophie était observée dans 05 cas avec un seul cas d'hémarthrose. Une nette amélioration du score ICRS était observée avec une moyenne qui a passée du 54% à 74% au recul. Les patients satisfaits ou très satisfaits (82,9%) furent largement majoritaires. Les éléments de bon pronostic constatés dans notre étude étaient: un délai opératoire moins de 18 mois de début de la symptomatologie, les lésions profondes ayant un diamètre inférieur à 02 cm et les lésions siégeant au niveau du condyle interne. Le traitement des pertes de substances cartilagineuses passe obligatoirement par la correction des causes directes et indirectes à savoir le morphotype, la laxité et le capital méniscal. Aucun consensus décisionnel n'a pu être proposé et nul ne peut confirmer la supériorité d'une technique par rapport à l'autre mais nous pouvons dire que le défect cartilagineux de 2 à 4 cm2 peut être la meilleure indication à la mosaïcoplastie

Review on discharge Plasma for water treatment: mechanism, reactor geometries, active species and combined processes

Owing to the water crisis, the development of innovative and clean advanced oxidation processes to decompose a variety of harmful organic compounds in wastewater becomes the main challenge for many research teams. Cold discharge plasma is one of the most widely studied and developed processes, owing to its low energy cost and easy to operate. The impact of different factors on the decontamination effectiveness of discharge plasma are detailed in this review. The generation and reaction mechanisms of reactive species in discharge plasma systems have also gained a significant interest and hence discussed. Several potentials and laboratory-scale reactor design recently reported are discussed and schematically presented. The recent combination of discharge plasma decontamination and other processes in both post and pre-treatment configuration are reported. Some applications of water treatment based on discharge plasma at the pilot scale have been addressing

Production et caractérisation des charbons actifs à partir du bois et autres déchets végétaux (application en traitement des eaux)

Des analyses thermogravimétriques de la décomposition thermique de la cellulose ont été réalisées. Un modèle cinétique de type Prout-Tomkins est adapté à la pyrolyse de la cellulose. L'énergie d'activation correspondante à la cellulose, la lignine et le xylane a été identifiée en mode dynamique. Le charbon actif produit à partir du bois et de ses principaux constituants de base a été caractérisé par BET et adsorption en solution aqueuse. Des mesures simultanées d'ATD et d'ATG ont servi à comparer les thermicités et les vitesses de décomposition de ces différents constituants. La thermocompression a permis de conférer au bois une densité deux fois supérieure à celle du bois brut. L'activation chimique a permis d'obtenir des surfaces spécifiques élevées ainsi que de bonnes capacités d'adsorption. Des mesures de capacité d'adsorption d'ions métalliques donnent des résultats importants. Une loi cinétique pseudo ordre 2 simule correctement l'adsorption de Cr(VI) en solution.The kinetics of cellulose pyrolysis were studied from thermogravimetric data. The kinetic model of Prout-Tomkins type is adapted to the pyrolysis of cellulose. The energy of activation corresponding to cellulose, lignin and xylan has been identified in dynamic mode. The activated carbon produced from wood and its basic components have been characterised by BET and adsorption from aqueous solution. Simultaneous measurements of DTA-TGA allowed to compare the heat of reaction and the decomposition rate of the wood components. Its Chemical activation by KOH and H3PO4 produce AC with height surface and adsorption capacity. Thermocompression confer to the wood a density two times larger than its initial density. Chemical activation with KOH results in a high surface area with a good adsorption capacity AC. The measurements of adsorption capacities of metal ions provide relevant results. The kinetics of the sorption process are found to follow the pseudo-second order law.COMPIEGNE-BU (601592101) / SudocSudocFranceF

Treatment of Mixture Pollutants with Combined Plasma Photocatalysis in Continuous Tubular Reactors with Atmospheric-Pressure Environment: Understanding Synergetic Effect Sources

International audienceThis study investigates the pilot-scale combination of nonthermal plasma and photocatalysis for removing Toluene and dimethyl sulfur (DMDS), examining the influence of plasma energy and initial pollutant concentration on the performance and by-product formation in both pure compounds and mixtures. The results indicate a consistent 15% synergy effect, improving Toluene conversion rates compared to single systems. Ozone reduction and enhanced CO2 selectivity were observed when combining plasma and photocatalysis. This process effectively treats pollutant mixtures, even those containing sulfur compounds. Furthermore, tests confirm nonthermal plasma’s in-situ regeneration of the photocatalytic surface, providing a constant synergy effect

1,2,3,4-Tetrahydropyrimidine Derivative for Selective and Fast Uptake of Cadmium Ions from Aqueous Solution

The aim of this work was to evaluate the performance of a 1,2,3,4-tetrahydropyrimidine derivative as a powerful heterocyclic compound for the elimination of Cd(II) ions from aqueous solutions. The tetrahydropyrimidine derivative was prepared during 30 min of milling by planetary ball mill with a ball-to-powder mass ratio of 8:1 and a rotation speed of 750 rpm. Nuclear magnetic resonance (NMR) and infrared (IR) were used to identify the obtained tetrahydropyrimidine derivatives. Furthermore, batches of experiments were carried out to establish the adsorption equilibrium, kinetics, and thermodynamic variables of the tetrahydropyrimidine derivatives for toxic heavy Cd(II) ions. The adsorption data were simulated by applying the Langmuir manner, the Freundlich equation, the pseudo-first-order and pseudo-second-order equations. The adsorption procedure was discovered to be very influenced by PH. The removal of heavy metal ions reached a maximum value quickly within 6 min and the adsorption data better adjusted the Langmuir isotherm than that of the Freundlich isotherm. The maximum Cd(II) ions adsorption capacity was approximated to be 151.16 mg g−1 at 328 K and a pH of 6 to 7. It was found that the adsorption kinetics of Cd(II) ions obeyed pseudo-second-order adsorption kinetics. The examination of the thermodynamic variables of tetrahydropyrimidine derivative showed a spontaneous endothermic adsorption procedure. Otherwise, positive entropy values put forward a rise in the randomness at the solid-solution interface when heavy metal ions are adsorbed

TOTAL VALORISATION OF RED CEDAR (THUJA PLICATA) SAWMILLS WASTES. ISOLATION OF EXTRACTIVES AND PRODUCTION OF ACTIVATED CARBON FROM THE SOLID RESIDUE

International audienceExperiments were performed to evaluate a recent extraction process called the instantaneous controlled pressure drop process (briefly: DIC process: “Détente Instantanée Contrôlée”) for extracting some volatile compounds from red cedar wood. This process involves subjecting red cedar chips for a short time (30 s to 5 min) under a steam pressure (1 to 6 bars or from 100 to 165 °C). This first step is followed by a flash decompression toward vacuum (up to 50 mbar). This transition induces a fast evaporation of water and volatile compounds and a cooling effect. The effects of two processing parameters (steam pressure and heating time) on the total extraction yield and on yield of four volatile compounds were evaluated by response surface methodology. The results indicated that the processing pressure is the predominant parameter for global extraction yield of oil (E.O= Extracted Oil) and for yield of the four compounds investigated in this study. The processing time is also a significant parameter but less than processing pressure. Moreover, activated carbon produced from DIC-treated residue revealed larger pore sizes compared to untreated samples

Gaseous ethylbenzene removal by photocatalytic TiO(2) nanoparticles immobilized on glass fiber tissue under real conditions: evaluation of reactive oxygen species contribution to the photocatalytic process

International audiencePhotocatalytic oxidation (PCO) using a TiO(2) catalyst is an effective technique to remove gaseous volatile organic compounds (VOCs). Herein, a lab-scale continuous reactor is used to investigate the photocatalytic performance toward ethylbenzene (EB) vapor removal over TiO(2) nanoparticles immobilized on glass fiber tissue. The role of the reactive species in the removal of EB and the degradation pathway were studied. Firstly, the effect of key operating parameters such as EB concentration (13, 26, 60 mg/m(3)), relative humidity levels (From 5 to 80%), gas carrier composition (dry air + EB, O(2) + EB and N(2) + EB) and ultraviolet (UV) radiation wavelength (UV-A (365 nm), UV-C (254 nm)) were explored. Then, using superoxide dismutase and tert-butanol as trapping agents, the real contribution of superoxide radical anion (O(2)(.-)) and hydroxyl radicals (OH(.)) to EB removal was quantified. The results show that (i) small water vapor content enhances the EB degradation; (ii) the reaction atmosphere plays an important role in the photocatalytic process; and (iii) oxygen atmosphere/UV-C radiation shows the highest EB degradation percentage. The use of radical scavengers confirms the major contribution of the hydroxyl radical to the photocatalytic mechanism with 75% versus 25% for superoxide radical anion

An Overview of Recent Developments in Improving the Photocatalytic Activity of TiO(2)-Based Materials for the Treatment of Indoor Air and Bacterial Inactivation

International audienceIndoor air quality has become a significant public health concern. The low cost and high efficiency of photocatalytic technology make it a natural choice for achieving deep air purification. Photocatalysis procedures have been widely investigated for environmental remediation, particularly for air treatment. Several semiconductors, such as TiO(2), have been used for photocatalytic purposes as catalysts, and they have earned a lot of interest in the last few years owing to their outstanding features. In this context, this review has collected and discussed recent studies on advances in improving the photocatalytic activity of TiO(2)-based materials for indoor air treatment and bacterial inactivation. In addition, it has elucidated the properties of some widely used TiO(2)-based catalysts and their advantages in the photocatalytic process as well as improved photocatalytic activity using doping and heterojunction techniques. Current publications about various combined catalysts have been summarized and reviewed to emphasize the significance of combining catalysts to increase air treatment efficiency. Besides, this paper summarized works that used these catalysts to remove volatile organic compounds (VOCs) and microorganisms. Moreover, the reaction mechanism has been described and summarized based on literature to comprehend further pollutant elimination and microorganism inactivation using photocatalysis. This review concludes with a general opinion and an outlook on potential future research topics, including viral disinfection and other hazardous gases

Les exostoses de Turrett’s: à propos de 35 cas

Nous rapportons à travers une étude rétrospective faite de 35 cas d’exostose sous unguéale de l’hallux dite exostose de Turrett's colligée entre 1995 et 2015 au service d’Orthopédie Traumatologie de l’Hôpital Militaire Principal d’Instruction de Tunis les résultats de la prise en charge de cette pathologie faite d’adultes jeunes d’âge moyen de 29 ans avec un sexe ratio de 1,7. Le délai moyen de consultation est de 18 mois. Ce retard de consultation est expliqué par une errance diagnostique en rapport avec une ressemblance du tableau clinique avec celui d’un ongle incarné. Le diagnostic est toujours confirmé par une radiographie de face et de profil de l’orteil intéressé. Le traitement a consisté en une exérèse radicale de l’exostose soit à travers une large fenêtre unguéale soit par un abord latéro-unguéal. L’examen anatomopathologique est systématique. Il a permis de confirmer la bénignité de l’affection dans tous les cas. La guérison a été de règle dans tous les cas avec une reprise de l’activité antérieure en 2 mois en moyenne. Aucune récidive n’a été notée