144 research outputs found

    Progress on the Strong Eshelby's Conjecture and Extremal Structures for the Elastic Moment Tensor

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    We make progress towards proving the strong Eshelby's conjecture in three dimensions. We prove that if for a single nonzero uniform loading the strain inside inclusion is constant and further the eigenvalues of this strain are either all the same or all distinct, then the inclusion must be of ellipsoidal shape. As a consequence, we show that for two linearly independent loadings the strains inside the inclusions are uniform, then the inclusion must be of ellipsoidal shape. We then use this result to address a problem of determining the shape of an inclusion when the elastic moment tensor (elastic polarizability tensor) is extremal. We show that the shape of inclusions, for which the lower Hashin-Shtrikman bound either on the bulk part or on the shear part of the elastic moment tensor is attained, is an ellipse in two dimensions and an ellipsoid in three dimensions

    Pyocele du cornet moyen : a propos d’un cas

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    Introduction : Les mucocĂšles sont des formations kystiques bĂ©nignes mais expansives, tapissĂ©es par un Ă©pithĂ©lium respiratoire, sans connexion avec les cavitĂ©s sinusiennes ou nasales. Elles se dĂ©veloppent le plus souvent dans le complexe ethmoĂŻdofrontal. Le terme pyocĂšle correspond Ă  une mucocĂšle dont le contenu est infectĂ©. La localisation turbinale moyenne est exceptionnelle.Observation : Nous rapportons l’observation d’un patient ĂągĂ© de 75 ans qui se plaignait d’une obstruction nasale chronique gauche. L’examen clinique montrait un cornet moyen Ă©largi obstruant la totalitĂ© de la fosse nasale gauche. L’Imagerie (TDM et IRM) a rĂ©vĂ©lĂ©e une formation ovalaire d’allure kystique expansive dĂ©veloppĂ©e aux dĂ©pens du cornet moyen, associĂ©e Ă  un polype postĂ©rieur. Le diagnostic de mucocĂšle sur concha bullosa a Ă©tĂ© portĂ©. Le patient a Ă©tĂ© opĂ©rĂ© par voie endonasale avec marsupialisation et polypectomie. Les suites opĂ©ratoires Ă©taient simples avec amĂ©lioration des signes cliniques.Conclusion : Les pyocĂšles du cornet moyen sont des lĂ©sions rares bĂ©nignes, toutefois destructrices. Un bilan radiologique est indispensable pour guider le choix du traitement chirurgical. La voie endonasale reste le traitement de rĂ©fĂ©rence pour cette pathologie.Mots clĂ©s : Concha bullosa, PyocĂšle, Obstruction nasaleIntroduction : A mucocele is an epithelium-lined cavity that contains mucus that fills the sinus and is capable of expansion. The majority of mucoceles are situated in the frontal and/or ethmoid sinuses. A pyocele occurs when a mucocele becomes infected. Concha bullosa mucopyocele is a rare entity that presents with persistent nasal symptoms.Case report : This paper presents patient aged 75 who were admitted with persistent nasal complaints. Anterior rhinoscopy showed enlarged middle turbinates obstructing the nasal cavities. MRI and CT Scann revealed expansif cystic lesion in the middle turbinate with a nasal polyp. With the diagnosis of concha bullosa mucocele, lateral part of the affected middle turbinate and the polyp were resected with an endoscopic approach. There were no intraoperative or postoperative complications. Nasal obstruction vanished postoperatively.Conclusion: Mucopyocele of middle turbinate are rare benign lesions. Radiological assessment is essential to guide the choice of surgical treatment. Endonasal approach is the standard treatment for this disease.Key words : Concha bullosa, Pyocele, Nasal obstructio

    Mucocele geante de l’enfant

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    Les mucocĂšles sont des formations pseudo kystiques expansives des sinus de la face. Elles sont souvent diagnostiquĂ©es tardivement du fait de l’absence de signes spĂ©cifiques. Le bilan radiologique basĂ© sur la TDM et ou l’IRM est essentiel pour confirmer le diagnostic et Ă©tablir le bilan d’extension. Nous rapportons le cas d’un enfant ĂągĂ© de 4 ans et 6mois traitĂ© d’une mucocĂšle gĂ©ante Ă©thmoĂŻdo- maxillaire.Mots clĂ©s : mucocĂšle ; enfant ; TDM ; IRM ; chirurgieMucoceles are pseudo-cystic expansive formations of the sinuses. They are often diagnosed lately because of the lack of specific signs. CT and MRI are essential for the diagnosis and to evaluate the extension.We report a case of child with ethmoide-maxillary mucocĂšle treated in our department.Key words: mucocele; child; CT; MRI; surger

    Valeur de l’examen extemporane en pathologie thyroïdienne

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    OBJECTIF : Etudier la valeur de l’examen extemporanĂ© dans la pathologie thyroidienne et identifier ses limitesMATERIELS ET METHODES : Notre Ă©tude est rĂ©trospective incluant 800 examens extemporanĂ©s rĂ©alisĂ©s sur des piĂšces de rĂ©sectionthyroĂŻdienne colligĂ©s dans notre service sur une pĂ©riode de 12 ans (2000-2011).Les rĂ©sultats ont Ă©tĂ© comparĂ©s Ă  ceux del’examen anatomopathologique dĂ©finitif.RESULTATS : Les rĂ©sultats Ă©taient concordants dans 96,5%, discordants dans 3,5 %. La sensibilitĂ© de l’examen extemporanĂ© toustypes confondus Ă©tait de 78 % et la spĂ©cificitĂ© de 100 %CONCLUSION : Notre Ă©tude a montrĂ© une spĂ©cificitĂ© parfaite de l’examen extemporanĂ© cependant l’interprĂ©tation difficile des lĂ©sionsthyroĂŻdiennes d’architecture vĂ©siculaire expliquent une sensibilitĂ© de 78 %.Mots ClĂ©s : ThyroĂŻdectomie, 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

    Les goitres plongeants : particularites cliniques, radiologiques et therapeutiques

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    Introduction: Les goitres plongeants, devenus rares de nos jours, posent des problĂšmes diagnostiques et chirurgicaux particuliers. Leur prise en charge est facilitĂ©e par l’apport de la tomodensitometrie permettant de planifier l’attitude thĂ©rapeutique.Le but de ce travail est de prĂ©ciser les modalitĂ©s d’exploration et de prise en charge chirurgicale des goitres plongeants.MatĂ©riels et mĂ©thodes : Nous rapportons une Ă©tude rĂ©trospective portant sur42 cas de goitre plongeant colligĂ©s sur une pĂ©riode de 11 ans entre 2001 et 2011.RĂ©sultats : L’ñge moyen de nos patients Ă©tait de 56,9 ans (36-86 ans). Le sex-ratio Ă©tait de 0,13. La tumĂ©faction basi-cervicale Ă©tait le motif de consultation le plus frĂ©quent, rapportĂ©e dans 74 % des cas associĂ©e Ă  des signes de compression oesotrachĂ©ale dans 45% des cas.Une paralysie rĂ©currentielle unilatĂ©rale a Ă©tĂ© objectivĂ©e dans 3 cas.Une radiographie de thorax a montrĂ© un Ă©largissement mĂ©diastinal dans 23% des cas avec dĂ©viation trachĂ©ale chez63 % des malades. Une TDM cervico-thoracique pratiquĂ©e dans 85% des cas a confirmĂ© le diagnostic. Le traitement chirurgical Ă©tait menĂ© par voie cervicale exclusive chez tous les patients. Une paralysie rĂ©curentielle a Ă©tĂ© observĂ©e dans 3 cas. Aucune hypoparathyroĂŻdie dĂ©finitive n’a Ă©tĂ© rapportĂ©e avec un reculmoyen de 24mois.Conclusion : Les goitres plongeants devenus rares du fait de la prise en charge plus prĂ©coce des nodules thyroĂŻdiens. Ils posent actuellement moins de difficultĂ©s thĂ©rapeutiques. L’indication chirurgicale est toujours formelle devant le risque vital qu’ils posent.Mots clĂ©s : goitre cervicothoracique, thyroĂŻdectomie, paralysie rĂ©currentielle, hypoparathyroĂŻdie.Introduction: Substernal goiters, becoming rare, present diagnositic and therapeutic problems.Their management is facilitated by the contribution of computed tomography for planning the therapeutic approach. The aim of this study is to specify the procedures for exploration and surgical management of substernal goiters.Materials and Methods: We report a retrospective study of 42 cases of substernalgoiters collaged over a period of 11 years between 2001 and 2011.Results: The mean age was 56,9 years (36- 86 years). The sex ratio was 0,13. Cervical swelling was the most common reason for consultation, reported in 74% of cases associated with signs of oesotrachealcompression in 45% of cases. Unilateral laryngeal palsy has been objectified in 3 cases. Chest-x-Ray showed widening of mediastinal shadowwith tracheal deviation in 63% of patients. A cervico-thoracic CT performed in 85% of cases confirmed the diagnosis of substernal goiters. The cervical approach has been used in all cases. Laryngeal nerve palsy was observed in 3 cases. No definitive hypoparathyroidism have been reported with a mean of 24 months.Conclusion: Substernal goiters become rare due to the earlier diagnosis of thyroid nodules. They currently present fewer therapeutic difficulties, and must be managed surgically because of vital risk.Key words: substernal goiter, thyroidectomy, laryngeal nerve palsy, hypoparathoidism

    Soil moisture active and passive microwave products: intercomparison and evaluation over a Sahelian site

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    This paper presents a comparison and an evaluation of five soil moisture products based on satellite-based passive and active microwave measurements. Products are evaluated for 2005–2006 against ground measurements obtained from the soil moisture network deployed in Mali (Sahel) in the framework of the African Monsoon Multidisciplinary Analysis project. It is shown that the accuracy of the soil moisture products is sensitive to the retrieval approach as well as to the sensor type (active or passive) and to the signal frequency (from 5.6 GHz to 18.8 GHz). The spatial patterns of surface soil moisture are compared between the different products at meso-scale (14.5° N–17.5° N and 2° W–1° W). A general good consistency between the different satellite soil moisture products is shown in terms of meso-scale spatial distribution, in particular after convective rainfall occurrences. Comparison to ground measurement shows that although soil moisture products obtained from satellite generally over-estimate soil moisture values during the dry season, most of them capture soil moisture temporal variations in good agreement with ground station measurements

    A Mathematical Model and a Firefly Algorithm for an Extended Flexible Job Shop Problem with Availability Constraints

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    Manufacturing scheduling strategies have historically ignored the availability of the machines. The more realistic the schedule, more accurate the calculations and predictions. Availability of machines will play a crucial role in the Industry 4.0 smart factories. In this paper, a mixed integer linear programming model (MILP) and a discrete firefly algorithm (DFA) are proposed for an extended multi-objective FJSP with availability constraints (FJSP-FCR). Several standard instances of FJSP have been used to evaluate the performance of the model and the algorithm. New FJSP-FCR instances are provided. Comparisons among the proposed methods and other state-of-the-art reported algorithms are also presented. Alongside the proposed MILP model, a Genetic Algorithm is implemented for the experiments with the DFA. Extensive investigations are conducted to test the performance of the proposed model and the DFA. The comparisons between DFA and other recently published algorithms shows that it is a feasible approach for the stated problem

    Obese father's metabolic state, adiposity, and reproductive capacity indicate son's reproductive health

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    ObjectiveTo determine whether dietary and exercise regimes in obese males can provide a novel intervention window for improving the reproductive health of the next generation.DesignExperimental animal study.SettingUniversity research facilities.Animal(s)C57BL6 male and female mice.Intervention(s)Mice were fed a control diet (6% fat) or high-fat diet (21% fat) for 9 weeks. After the initial feeding, high-fat-diet males were allocated to diet and/or exercise interventions for a further 9 weeks. After intervention males were mated with females fed standard chow (4% fat) before and during pregnancy.Main outcome measure(s)F1 sperm motility, count, morphology, capacitation, mitochondrial function, and sperm binding and weight of reproductive organs.Result(s)Our primary finding was that diet intervention alone in founders improved offspring sperm motility and mitochondrial markers of sperm health (decreased reactive oxygen species and mitochondrial membrane potential), ultimately improving sperm binding. Sperm binding and capacitation was also improved in F1 males born to a combined diet and exercise intervention in founders. Founder sperm parameters and metabolic measures as a response to diet and/or exercise (i.e., lipid/glucose homeostasis, sperm count and morphology) correlated with offspring's sperm function, independent of founder treatment. This implicates paternal metabolic and reproductive status in predicting male offspring's reproductive function.Conclusion(s)This is the first study to show that improvements to both metabolic (lipids, glucose and insulin sensitivity) and reproductive function (sperm motility and morphology) in obese fathers via diet and exercise interventions can improve subsequent reproductive health in offspring.Nicole O. McPherson, Tod Fullston, Hassan W. Bakos, Brian P. Setchell and Michelle Lan

    Morphological effects on IR band profiles: Experimental spectroscopic analysis with application to observed spectra of oxygen-rich AGB stars

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    To trace the source of the unique 13, 19.5, and 28 ÎŒ\mum emission features in the spectra of oxygen-rich circumstellar shells around AGB stars, we have compared dust extinction spectra obtained by aerosol measurements. We have measured the extinction spectra for 19 oxide powder samples of eight different types, such as Ti-compounds (TiO, TiO2_2, Ti2_2O3_3, Ti3_3O5_5, Al2_2TiO5_5, CaTiO3_3), α\alpha-, Îł\gamma-, χ\chi-ÎŽ\delta-Îș\kappa-Al2_2O3_3, and MgAl2_2O4_4 in the infrared region (10 - 50 ÎŒ\mum) paying special attention to the morphological (size, shape, and agglomeration) effects and the differences in crystal structure. Anatase (TiO2_2) particles with rounded edges are the possible 13, 19.5 and 28 ÎŒ\mum band carriers as the main contributor in the spectra of AGB stars, and spherically shaped nano-sized spinel and Al2_2TiO5_5 dust grains are possibly associated with the anatase, enhancing the prominence of the 13 ÎŒ\mum feature and providing additional features at 28 ÎŒ\mum. The extinction data sets obtained by the aerosol and CsI pellet measurements have been made available for public use at http://elbe.astro.uni-jena.deComment: 17 pages, 8 figures, Accepted 24 March 2009 for publication in A&
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