261 research outputs found

    Technique de datation des échantillons riches en uranium par les séries de l'uranium en utilisant la spectrométrie gamma à basse énergie

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    Dating technique of samples rich in uranium by the series of the uranium by using the gamma spectrometry with low energyIn this work, a dating technique by the series of the uranium using the gamma spectrometry with Flow energy

    Raising children's learning and performance : a study in a large UK primary school.

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    Raising children's learning and performance and implementing effective strategies to improve standards represent continuous challenges for government policy makers, schools and teachers. Whilst school effectiveness and school improvement policies and strategies have endeavoured to do this through various strategies, the key to sustainable effective improvements in different contexts remains elusive. This study is complementary to school policy studies and provides a different way of raising children's learning and performance. The study also addresses a gap in the literature. The approach adopted was to focus on children through targeting various holistic interventions in the form of sound and movement programmes in order to remediate the underlying causes of under performance by children. The study also adopted a novel approach of combining the two interventions, referred to in this study as an integrated approach. To date, most studies have focused on external conditions or on the enablers to providing effective learning experiences. In recent years, there have been new and innovative interventions used in private institutions using more holistic ways of improving children's learning and performance. This research builds on this approach and attempts to extend the ideas generated in the private institutions by investigating these approaches in a school context with the hope of furthering the knowledge in this field. In addition, the aim is to propose a holistic model for raising children's learning and performance which capitalises on the work of school effectiveness and school improvement research, to date, in their bid to raise children learning. To achieve this objective a quasi-experimental, exploratory study which adopted quantitative methods of data collection was used in a school, with four parallel classes (in total 119 children) aged nine/ten years, using the following standardised tests: Suffolk Group Reading Test, the NFER Non- verbal (NFER Nelson) and TAPS-R (Gardner 1985) Digit Span Test to measure and gain an overall picture of any impact made by the interventions. The experimental study took place over a period of eight months. Two classes completed the individual interventions, whilst one completed both as an integrated approach and one class had no intervention. Results showed that the movement interventions and the integrated intervention raised overall performance. However, the sound intervention raised only reading performance. The integrated intervention did not show increased results over and above the two individual interventions, leading to the conclusion that it did not generate a significant and marked impact. Based on the empirical findings and on the literature, a model of the Child Centric Learning Effectiveness Cycle (CCLEC) was proposed to help raise children's learning and performance in schools

    Angiodysplasies des maxillaires de l’enfant

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    Les angiodysplasies des maxillaires sont des affections rares et graves. Leur mauvais pronostic est surtout lié aux complications hémorragiques redoutables, dues le plus souvent à des extractions dentaires abusives sans examens radiologiques préalables. L’angio-IRM a permis d’une manière non invasive une meilleure connaissance de ces lésions en étudiant leur angio-architecture et leur hémodynamique. Jadis, le seul traitement efficace consistait en une exérèse chirurgicale mutilante entraînant des complications esthétiques et fonctionnelles sévères avec une morbidité importante. Actuellement, la radiologie interventionnelle a révolutionné la prise en charge grâce à l’artériographie hypersélective et àla découverte de nouveaux matériaux d’obturation plus faciles à manier. L’embolisation hypersélective est devenue l’arme de première intention en raison de son caractère conservateur et de son faible taux de  complications. Le but de ce travail est de rappeler les différents aspects étiopathogéniques, cliniques et para cliniques des angiodysplasieset de définir l’attitude thérapeutique.Mots clefs : angiodysplasie, embolisation, chirurgie

    Laryngocele a propos de 9 cas

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    La laryngocèle est une pathologie rare. elle est définit par la dilatation progressive du saccule laryngé. Le diagnostic est suspecté par l’examen clinique, sa prise en charge est encore discutée. nous rapportons une étude rétrospective portant sur 9 patients ayant été suivis et traités pour une laryngocèle. La série a été colligée sur une période de 14 ans, allant de 1998 à 2011. Six de nos patients avaient une laryngocèle externe, deux patients avaient une laryngocèle mixte et un patient avait une laryngocèle interne. Une surinfection a été notée chez trois patients réalisant ainsi le tableau de pyolaryngocèle. Tous les patients ont eu un examen clinique complet comportant un examen OrL et cervico-facial ainsi qu’un examen laryngé au nasofibroscope. La tomodensitométrie cervicale a été réalisée de façon systématique. Huit de nos malades ont été abordés par voie cervicale permettant une exérèse complète du sac. Le recul moyen était de 38 mois sans récidive. Toute laryngocèle découverte, doit être traitée afin d’éviter les complications essentiellement locales pouvant mettre en jeu le pronostic vital. Les modalités thérapeutiques dépendent du type de la laryngocèle.Mots-clés : laryngocèle, nasofibroscopie laryngée, traitement endoscopique, thyrotomie.A laryngocele is a rare affection which consists in an abnormal dilatation of the laryngeal saccule. The diagnosis is suspected after clinical exam. The management of this pathology remains a subject of debating. We report a retrospective review including nine patients with laryngocele treated over a 14 years-period. Six patients had external laryngoceles; two had combined laryngocele; another one had an internal laryngocele. Preoperative diagnosis of each patient was made on flexible nasolaryngoscopy following routine otorhinolaryngologic exam. CT scan was systematically done. mrI was realized in case of a diagnostic doubt. eight of our patients were treated via external approach. no recurrences were encountered during the following-up. Laryngoceles must be treated to provide different complications. Some of these complications can cause death. The modalities of the treatment depend on the type of laryngocele.Keywords : laryngocele, nasolaryngoscopy, endoscopic treatment, thyrotomy

    Valeur de l’examen extemporane en pathologie thyroïdienne

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    OBJECTIF : Etudier la valeur de l’examen extemporané dans la pathologie thyroidienne et identifier ses limitesMATERIELS ET METHODES : Notre étude est rétrospective incluant 800 examens extemporanés réalisés sur des pièces de résectionthyroïdienne colligés dans notre service sur une période de 12 ans (2000-2011).Les résultats ont été comparés à ceux del’examen anatomopathologique définitif.RESULTATS : Les résultats étaient concordants dans 96,5%, discordants dans 3,5 %. La sensibilité de l’examen extemporané toustypes confondus était de 78 % et la spécificité de 100 %CONCLUSION : Notre étude a montré une spécificité parfaite de l’examen extemporané cependant l’interprétation difficile des lésionsthyroïdiennes d’architecture vésiculaire expliquent une sensibilité de 78 %.Mots Clés : Thyroïdectomie, examen extemporanOBJECTIVE: To assess the value of frozen-section examination in thyroid surgery and evaluate its limitationsPATIENTS AND METHODES: This retrospective study examined the results of 800 frozen-sections of thyroid specimens analysedover the 12 –year period (2000-2011). Their results were compared with definitive anatomo-pathological examinationRESULTS :Frozen-section diagnosis was concordant with subsequent histopathological examination in 96,5% ,discordant in 3,5%.The global specificity of frozen section analysis for all histological subtypes was 100 % and its sensitivity was 78 %.CONCLUSION: This study shows the good specificity of frozen section .Discordances between frozen-section and definitive diagnosiswas associated with microfllicular lesions wich explain the sensibility of 78%Key Words: Thyroid surgery, frozen section examinatio

    Effect of O2 increase on properties of vanadium oxide coatings

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    The present research was carried out with the aim of studying the influence of oxygen concentration during processing on the properties of the VOx coatings deposited by cathodic magnetron sputtering on a stainless steel AISI 316L substrate. Mechanical and tribological properties were measured by nanoindentation and sliding wear tests respectively. Adhesion was evaluated by means of the scratch test. In order to determine the texture of the coatings, complementary characterization methods including X-ray diffraction in grazing incidence and Bragg Brentano configurations, as well as V scans, were performed. It was found that the texture of the crystalline coatings is strongly influenced by the amount of partial pressure of oxygen in the reactor atmosphere. The V2O5 phase, with an orthorhombic symmetry, was produced in the coating, which had a pronounced texturing for the (001) plane, exhibiting the best values of hardness and Young modulus. It was shown that, as the oxygen concentration drops to ,1 sccm, the mechanical and tribological characteristics, as well as the coating adhesion, tend to decrease considerably
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