Méningiome primitif ethmoïdonasal.

Introduction : Les méningiomes primitifs des fosses nasales et des sinus paranasaux sont des tumeurs bénignes rares, la sémiologie clinique et radiologique n’est pas spécifique. L’objectif de ce travail est de décrire les aspects épidémiologiques, diagnostiques et thérapeutiques de cette localisation ectopique des méningiomes.Observation : Patient âgé de 52 ans, présentant une obstruction nasale bilatérale avec hyposmie et épistaxis depuis 4 ans, l’examen endonasal a montré un processus tissulaire polypoïde occupant les deux fosses nasales, la TdM a montré un processus tumoral ethmoïdonasal étendu aux sphénoïdes et vers les deux fosses nasales sans extension endocrânienne. Le patient a été opéré par voie transfaciale, l’examen anatomopathologique était en faveur d’un méningiome méningothélial gradei. Les contrôles cliniques, endoscopiques et scannographiques n’ont pas montré de résidu tumoral ni de récidive avec un recul de 4ans.Conclusion : Les fosses nasales et les sinus paranasaux représentent une localisation ectopique exceptionnelle des méningiomes extra crâniens primitifs. Ces tumeurs se développent lentement et leur pronostic est généralement bon après exérèse chirurgicale.Mots clés : Méningiomes ectopiques, sinus paranasaux, anatomie pathologique, immunohistochimie, chirurgie.Introductione : Primary extracranial meningiomas of the nasal cavity and paranasal sinuses are rare benign tumors, the clinical and radiological presentations are not specific. The objective of this work is to describe the epidemiological, diagnostic and therapeutic aspects of this ectopic location of meningiomas.Case report : 52-year-old patient, presented a bilateral nasal obstuction with hyposmie and epistaxis for 4 years, the endonasal examination showed a polypoid process occupying both nasal cavity, the CT examination showed a ethmoïdonasal tumoral process extending to sphenoid bones and both nasal cavity without endocranial extension. The patient was operated by transnasal approach, histopathological examination was in favour of a méningothélial meningioma rank i.The clinical, endoscopic and CT controls did not show tumor residue or a local recurrence with a recession of 4years. Nasal cavity and paranasal sinuses represent an exceptional ectopic location of primary extracranial meningiomas , these tumors are slowly growing, and their prognosis is generally good after surgical excision.Keyswords : ectopic meningioma, paranasal sinuses, histopathology, immunohistochemistry, surgery

Focused labeled proof systems for modal logic

International audienceFocused proofs are sequent calculus proofs that group inference rules into alternating positive and negative phases. These phases can then be used to define macro-level inference rules from Gentzen's original and tiny introduction and structural rules. We show here that the inference rules of labeled proof systems for modal logics can similarly be described as pairs of such phases within the LKF focused proof system for first-order classical logic. We consider the system G3K of Negri for the modal logic K and define a translation from labeled modal formulas into first-order polarized formulas and show a strict correspondence between derivations in the two systems, i.e., each rule application in G3K corresponds to a bipole—a pair of a positive and a negative phases—in LKF. Since geometric axioms (when properly polarized) induce bipoles, this strong correspondence holds for all modal logics whose Kripke frames are characterized by geometric properties. We extend these results to present a focused labeled proof system for this same class of modal logics and show its soundness and completeness. The resulting proof system allows one to define a rich set of normal forms of modal logic proofs

A Distributed and Trusted Web of Formal Proofs

International audienceMost computer checked proofs are tied to the particular technology of a prover's software. While sharing results between proof assistants is a recognized and desirable goal, the current organization of theorem proving tools makes such sharing an exception instead of the rule. In this talk, I argue that we need to turn the current architecture of proof assistants and formal proofs inside-out. That is, instead of having a few mature theorem provers include within them their formally checked theorems and proofs, I propose that proof assistants should sit on the edge of a web of formal proofs and that proof assistant should be exporting their proofs so that they can exist independently of any theorem prover. While it is necessary to maintain the dependencies between definitions, theories, and theorems, no explicit library structure should be imposed on this web of formal proofs. Thus a theorem and its proofs should not necessarily be located at a particular URL or within a particular prover's library. While the world of symbolic logic and proof theory certainly allows for proofs to be seen as global and permanent objects, there is a lot of research and engineering work that is needed to make this possible. I describe some of the required research and development that must be done to achieve this goal

A New Model for Polluted insulators Flashover under HVDC

International audienc

Posttraumatic Cholesteatoma Complicated by a Facial Paralysis: A Case Report

The posttraumatic cholesteatoma is a rare complication of different types of the temporal bone damage. Its diagnosis is often done after several years of evolution, sometimes even at the stage of complications. A case of posttraumatic cholesteatoma is presented that was revealed by a facial nerve paralysis 23 years after a crash of the external auditory canal underlining the importance of the otoscopic and radiological regular monitoring of the patients with a traumatism of the temporal bone

L’otite moyenne chronique cholestéatomateuse de l’enfant: à propos de 30 cas

Le cholstéatome de l'oreille moyenne est une otite chronique qualifiée de dangereuse en raison de ses risques évolutifs et de ses complications potentiellement graves pouvant mettre en jeu le pronostic vital. L'évolution du cholestèatome est sensiblement différente entre l'adulte et l'enfant, avec une agressivité particulière des cholestèatomes pédiatriques nécessitant ainsi une prise en charge adéquate. Le but de notre travail est d'analyser à travers une revue bibliographique les particularités des otites moyennes chroniques cholestèatomateuses chez 30 enfants pris en charge dans le service d'oto-rhino-laryngologie de l'hôpital militaire Avicenne de Marrakech. Le traitement est exclusivement chirurgical, actuellement, la plupart des auteurs optent pour l'utilisation d'une technique fermée en première intention chez l'enfant

Model for polluted insulator flashover under AC or DC voltage

International audienceThe aim of this paper is to elaborate a model describing the different phases of flashover of high voltage insulators with continuous or discontinuous pollution deposits, in AC or DC. This model uses an equivalent electrical circuit. It consists of three sub-algorithms: (1) The first one is a preliminary algorithm enabling the quantification of the electrical equivalent circuit parameters based on analytical and semi-analytical formulations; (2) the second one is relative to the steady state of discharge (static sub-model), at the beginning of flashover; and (3) the third one describes the unstable mode (dynamic sub-model). The whole algorithm describes the evolution of the discharge up to flashover. It enables to determine the different parameters characterizing the discharge such as the current, length, radius, propagation velocity, linear resistance and temperature. The simulated values are found in a good agreement with the experimental ones

Les carcinomes de la thyroïde: profils épidémiologique, clinique et thérapeutique, à propos de 102 cas

Les carcinomes thyroïdiens sont des tumeurs malignes assez rares,  représentant 1% des cancers. Ils sont généralement de bon pronostic, et présentent des aspects cliniques et évolutifs variés selon leur origine histologique. Notre travail est une étude rétrospective portant sur 102 cas de carcinomes de la thyroïde, colligés sur un nombre total de 811 gestes chirurgicaux thyroïdiens, au service d'oto-rhino-laryngologie et de chirurgie cervico-faciale de l'hôpital militaire Avicenne de Marrakech, sur une période de 8 ans, allant de janvier 2006 à décembre 2013.Les carcinomes thyroïdiens  atteignent le sujet jeune avant l'âge de 50 ans, en particulier le sexe féminin. La tendance dans les pays en voie de développement, comme dans le monde entier est en croissance continue, ceci peut être expliqué par l'amélioration  des outils d'imagerie et des moyens diagnostiques cytologiques et anatomo-pathologiques

Treatment of EVA with corona discharge to improve its adhesion to polychloroprene adhesive

Ethylene vinyl acetate (EVA) material containing 20 wt% vinyl acetate (EVA20) was treated with corona discharge to improve its adhesion to polychloroprene adhesive. Several experimental variables in the corona discharge treatment of EVA20 were considered: corona energy, type of electrode, and number of consecutive treatments. Advancing contact angle measurements (water, 25±C) showed an increase in the wettability of EVA20 after treatment with corona discharge, which corresponds to an increase in the O/C ratio on the treated surface. The higher the corona energy (i.e. the higher discharge power and longer treatment times), the greater the degree of surface oxidation. Peel strength values of the joints produced with EVA20 using a polychloroprene adhesive containing 5 wt% isocyanate increased from 1.5 kN/m (as-received EVA20) to 4.3 kN/m (corona-treated EVA20). A mixed (adhesional C cohesive in EVA20) locus of failure was obtained in all adhesive joints produced with corona discharge-treatedEVA20. Finally, the number of consecutive corona discharge treatments and the surface area of the electrode (spherical versus hook-shaped electrode) did not greatly influence the adhesion of EVA20 to polychloroprene adhesive