Fasciite nodulaire de la cavite buccale

Introduction: Nodular fasciitis is a benign tumour-like lesion characterized by fibroblastic proliferation. It is common in subcutaneous fascia, usually of the upper extremity but it's very rare in the oral cavity. Frequently misdiagnosed as sarcoma due to its rapid growth, rich cellularity and mitotic activity.Patients and Methods: One patient with an oral nodular fasciitis and a review of literature are reported in order to describe the diagnostic and therapeutic management of this tumour.Case presentation: A 50-year-old female with an intraorally swelling that had been growing progressively over one month. There was no history of trauma. Clinical examination revealed a firm mass palpable measuring approximately 4 cm in diameter. She had an excisional biopsy under local anaesthetic with histopathological analysis. The lesion was surgicalremoved under general anaesthesia through an intraoral approach. One year after excision of the tumour, the oral cavity was free of tumour.Conclusion: Nodular fasciitis is an entity characterized by rapid growth, rich cellularity and mitotic activity, although it is not malignant. It can only be diagnosed by histopathological examination of a biopsy with immunohistochemical staining.The treatment of choice is the complete surgical excision.Keywords: Nodular fasciitis, Oral cavity, Surgical treatment

Electrocoagulation as a green technology for phosphate removal from River water

The current study investigates the removal of phosphate from water using a new baffle plates aluminium-based electrochemical cell (PBPR) taking consideration the influence of key operating parameters. This new cell utilises perforated baffle plates as a water mixer rather than magnetic stirrers that require extra power to work. As this unit is new, a comprehensive study has been carried to assess it performance. This study also includes preliminary estimates of the reactor’s operating costs, the amount of H2 gas produced and the yieldable energy from it. SEM (scanning electron microscope) was used to investigate the influence of the electrocoagulation process on the morphology of the surface of aluminium electrodes, and an empirical model developed to reproduce the phosphate removal process. The results showed that 99% of phosphate was removed within 60 minutes of electrolysis at an initial pH (ipH) of 6, inter-electrode distance (ID) of 0.5 cm, current density (J) of 6 mA/cm2, initial concentration of phosphate (IC) of 100 mg/L, and minimum operating cost of 0.503 US $/m3. The electrochemical cell produced enough H2 gas to generate 4.34 kWh/m3 of power. Statistically, it was proved that the influence of the operating parameters on phosphate removal could be modelled with an R2 of 0.882, the influence of these operating parameters on phosphate removal following the order: t>J>IC>ipH >ID. Finally, SEM images showed that after several electrolysing runs, the Al anode became rough and nonuniform which could be related to the production of aluminium hydroxides

L'incertitude et l'imprecision dans les systemes a multi-sources de connaissances: le systeme ATOMIC

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : T 84144 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Déferrisation des eaux par procédé d’électrocoagulation : étude des phénomènes physico-chimiques et réactionnels impliqués

Water scarcity in some areas requires the exploitation of some ferruginous sources. However, the presence of Fe(II) induces aesthetic and organoleptic problems. The electrocoagulation (EC), as an alternative process of the conventional method, proved its efficacy for iron removal. Nevertheless, the iron removal mechanism in EC process remains unstudied and still unclear. The simultaneous involvement of several phenomena makes difficulties to study the system. This thesis aims to provide a better understanding of the mechanism of Fe(II) removal by EC and to highlight the phenomena that are most likely. Thus, different methods of iron removal and liquid and solid analysis techniques have been used. By means of a forced recirculating unit, EC's technique with aluminum electrodes reduce the dissolved iron of 25 mg Fe(II)/L - solution by about 97% with an optimum energy amount of 0,21 kWh/m3. Anoxic experiments showed that the reduction of ionic iron by adsorption on Al(OH)3 flocs is negligible (18%). Oxidation-precipitation experiments showed that at work pH 6,5, Al(OH)3 catalyzes the oxidation reaction. The catalytic effect is more pronounced in the presence of chloride ions than in sulfate ions. Fe(II)-speciation associated with kinetic modeling have allowed to explain of the mode by which these ions acts on the oxidation reaction kinetics. However, EC experiments in anoxic and oxygenated media show that the proportion of oxidation in iron removal is insignificant for work pH. Thermodynamic calculations allowed to propose the precipitation of Fe(OH)2 in the vicinity of the cathode as the predominant mechanism of iron removal by EC. The presence of carbonates affects the performance of the process by reducing the precipitation of Fe(OH)2; this was attributed to the decrease of the local pH and the free Fe(II) amount by Fe(II)-complexes formationLa demande croissante en eau nécessite l’exploitation de certaines sources ferrugineuses. Cependant la présence du Fe(II) dissous induit des problèmes d’ordre esthétique et organoleptique. L’électrocoagulation (EC), en tant que procédé substitut de la méthode conventionnelle, a prouvé son efficacité pour l’élimination du fer. En revanche, le mécanisme de déferrisation par EC reste peu connu et non maitrisé. La difficulté de l’étudier provient de l’intervention simultanée de plusieurs phénomènes. Les travaux de cette thèse ont de ce fait pour objectif d’apporter une meilleure compréhension du mécanisme d’élimination du Fe(II) par EC. Ainsi, différentes méthodes d’élimination du fer et des techniques d’analyses du liquide et du solide ont été exploitées. Au moyen d’une unité à recirculation forcée de la solution avec des électrodes en aluminium, la technique d’EC parvient à éliminer 97% d’une solution de 25 mg/L du fer. La quantité optimale d’énergie est de 0,21 kWh/m3. Des essais en milieu anoxique ont montré que la réduction du fer ionique par adsorption sur les flocs de Al(OH)3 est faible (18%). Par oxydation-précipitation à pH 6,5, le Al(OH)3 catalyse la réaction d’oxydation. Cet effet est plus prononcé en présence des ions chlorure qu’en ions sulfate. La spéciation associée à la modélisation cinétique ont permis d’apporter des explications sur le mode d’action de ces ions. Cependant, les expériences par EC en milieux anoxique et oxygéné montrent que la part de l’oxydation dans l’élimination du fer est négligeable pour les pH de travail. Les calculs thermodynamiques au voisinage des électrodes permettent de proposer la précipitation de Fe(OH)2, comme mécanisme prédominant d’élimination du fer par EC. La présence des carbonates réduit la performance du système par la réduction de la précipitation de Fe(OH)2 suite à la diminution du pH local et le Fe2+ libre par formation des complexes du Fe(II

Iron removal from water by electrocoagulation : investigation of the physico-chemical and reaction phenomena involved

La demande croissante en eau nécessite l’exploitation de certaines sources ferrugineuses. Cependant la présence du Fe(II) dissous induit des problèmes d’ordre esthétique et organoleptique. L’électrocoagulation (EC), en tant que procédé substitut de la méthode conventionnelle, a prouvé son efficacité pour l’élimination du fer. En revanche, le mécanisme de déferrisation par EC reste peu connu et non maitrisé. La difficulté de l’étudier provient de l’intervention simultanée de plusieurs phénomènes. Les travaux de cette thèse ont de ce fait pour objectif d’apporter une meilleure compréhension du mécanisme d’élimination du Fe(II) par EC. Ainsi, différentes méthodes d’élimination du fer et des techniques d’analyses du liquide et du solide ont été exploitées. Au moyen d’une unité à recirculation forcée de la solution avec des électrodes en aluminium, la technique d’EC parvient à éliminer 97% d’une solution de 25 mg/L du fer. La quantité optimale d’énergie est de 0,21 kWh/m3. Des essais en milieu anoxique ont montré que la réduction du fer ionique par adsorption sur les flocs de Al(OH)3 est faible (18%). Par oxydation-précipitation à pH 6,5, le Al(OH)3 catalyse la réaction d’oxydation. Cet effet est plus prononcé en présence des ions chlorure qu’en ions sulfate. La spéciation associée à la modélisation cinétique ont permis d’apporter des explications sur le mode d’action de ces ions. Cependant, les expériences par EC en milieux anoxique et oxygéné montrent que la part de l’oxydation dans l’élimination du fer est négligeable pour les pH de travail. Les calculs thermodynamiques au voisinage des électrodes permettent de proposer la précipitation de Fe(OH)2, comme mécanisme prédominant d’élimination du fer par EC. La présence des carbonates réduit la performance du système par la réduction de la précipitation de Fe(OH)2 suite à la diminution du pH local et le Fe2+ libre par formation des complexes du Fe(II)Water scarcity in some areas requires the exploitation of some ferruginous sources. However, the presence of Fe(II) induces aesthetic and organoleptic problems. The electrocoagulation (EC), as an alternative process of the conventional method, proved its efficacy for iron removal. Nevertheless, the iron removal mechanism in EC process remains unstudied and still unclear. The simultaneous involvement of several phenomena makes difficulties to study the system. This thesis aims to provide a better understanding of the mechanism of Fe(II) removal by EC and to highlight the phenomena that are most likely. Thus, different methods of iron removal and liquid and solid analysis techniques have been used. By means of a forced recirculating unit, EC's technique with aluminum electrodes reduce the dissolved iron of 25 mg Fe(II)/L - solution by about 97% with an optimum energy amount of 0,21 kWh/m3. Anoxic experiments showed that the reduction of ionic iron by adsorption on Al(OH)3 flocs is negligible (18%). Oxidation-precipitation experiments showed that at work pH 6,5, Al(OH)3 catalyzes the oxidation reaction. The catalytic effect is more pronounced in the presence of chloride ions than in sulfate ions. Fe(II)-speciation associated with kinetic modeling have allowed to explain of the mode by which these ions acts on the oxidation reaction kinetics. However, EC experiments in anoxic and oxygenated media show that the proportion of oxidation in iron removal is insignificant for work pH. Thermodynamic calculations allowed to propose the precipitation of Fe(OH)2 in the vicinity of the cathode as the predominant mechanism of iron removal by EC. The presence of carbonates affects the performance of the process by reducing the precipitation of Fe(OH)2; this was attributed to the decrease of the local pH and the free Fe(II) amount by Fe(II)-complexes formatio

Multi-level medical image thresholding based on metaheuristics: A comparative Study

International audienceno abstrac

Evaluation objective des méthodes de segmentation des maillages polygonaux 3D basée sur la classification de régions

International audienceIn this paper, we propose an objective evaluation approach of polygonal 3D mesh segmentation algorithms. Our approach is based on region classification. For that, we classify first manual segmented mesh into convex, concave and planar regions. Secondly, we present three quality measures that quantify the similarity of each type of region of the ground-truth relatively to the segmentation obtained by an automatic algorithm. We apply this approach on eight wellselected existing algorithms on heterogeneous images. This provides better understanding as to the strengths and weaknesses of each technique in function of each mesh-regions type in the aim to make the better choice concerning the segmentation algorithms for different applications.Dans ce papier, nous proposons une approche d'évaluation objective des algorithmes de segmentation des maillages polygonaux 3D, basée sur la classification de régions. Cette approche commence par un processus de classification de régions du maillage constituant la vérité-terrain en régions convexes, concaves et planes. Nous présentons ensuite trois mesures de qualité qui permettent de quantifier la similarité de chaque type de région de la vérité-terrain par rapport à la segmentation obtenue par un algorithme automatique. Nous appliquons l’approche proposée sur un échantillon de huit techniques de segmentation bien choisies sur une base d’images hétérogène. Les résultats d’évaluation obtenus permettent d’assurer une meilleure compréhension des points forts et faibles de chaque technique dans la segmentation des différents types de régions du maillage et ceci afin d’aiguiller correctement le choix des algorithmes de segmentation pour différentes applications

Birnessite: A New Oxidant for Green Rust Formation

Iron and manganese are ubiquitous in the natural environment. FeII-FeIII layered double hydroxide, commonly called green rust (GR), and MnIII-MnIV birnessite (Bir) are also well known to be reactive solid compounds. Therefore, studying the chemical interactions between Fe and Mn species could contribute to understanding the interactions between their respective biogeochemical cycles. Moreover, ferromanganese solid compounds are potentially interesting materials for water treatment. Here, a {Fe(OH)2, FeIIaq} mixture was oxidized by Bir in sulphated aqueous media in the presence or absence of dissolved O2. In oxic conditions for an initial FeII/OH− ratio of 0.6, a single GR phase was obtained in a first step; the oxidation kinetics being faster than without Bir. In a second step, GR was oxidised into various final products, mainly in a spinel structure. A partial substitution of Fe by Mn species was suspected in both GR and the spinel. In anoxic condition, GR was also observed but other by-products were concomitantly formed. All the oxidation products were characterized by XRD, XPS, and Mössbauer spectroscopy. Hence, oxidation of FeII species by Bir can be considered as a new chemical pathway for producing ferromanganese spinels. Furthermore, these results suggest that Bir may participate in the formation of GR minerals