2,845 research outputs found

    Structure and properties evolution with inorganic and organic acids of a new organo-chlorocadmate compound (C6H20N3)2[Cd2Cl10] : theoretical approach

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    This work was supported by the Ministry of Higher Education and Scientific Research of Tunisia.This work describes the theoretical studies of the reactivity, electrical and thermodynamic properties of a novel organo-chlorocadmate complex (C6H20N3)2[Cd2Cl10] and its inorganic and organic acid derivatives. The synthesis and crystal structure are described, with the compound crystallizing in the orthorhombic (Pnma) space group with unit cell parameters: a = 7.25494(11) Å, b = 29.3000(5) Å, c = 7.33927(13) Å. The semi-empirical calculations reveal that not only are all of the derivatives semiconductors, but also that the inclusion of acids in the structure alter the electrical and thermodynamic properties significantly, demonstrating a systematic and easy method for tuning the materials reactivity along with other desirable properties.PostprintPeer reviewe

    Layered structure transformations and exfoliation of h-BN during thermal cycling

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    Understanding structural transformation of hexagonal boron nitride (h-BN) at elevated temperatures is critical to obtain 2D-h-BN through thermal exfoliation. Therefore, in situ x-ray diffraction data are collected from h-BN powders while subjecting them to a thermal cycle. The potential to define the structure order during temperature variations is revealed by using an index (I3D). It was revealed that no direct correlation with the degree of exfoliation of layered structure and the structural order change appeared during thermal cycling. Furthermore, particle size dependence of the structure order under elevated temperature is also mapped

    Detection of skewed X-chromosome inactivation in Fragile X syndrome and X chromosome aneuploidy using quantitative melt analysis.

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    Methylation of the fragile X mental retardation 1 (FMR1) exon 1/intron 1 boundary positioned fragile X related epigenetic element 2 (FREE2), reveals skewed X-chromosome inactivation (XCI) in fragile X syndrome full mutation (FM: CGG > 200) females. XCI skewing has been also linked to abnormal X-linked gene expression with the broader clinical impact for sex chromosome aneuploidies (SCAs). In this study, 10 FREE2 CpG sites were targeted using methylation specific quantitative melt analysis (MS-QMA), including 3 sites that could not be analysed with previously used EpiTYPER system. The method was applied for detection of skewed XCI in FM females and in different types of SCA. We tested venous blood and saliva DNA collected from 107 controls (CGG < 40), and 148 FM and 90 SCA individuals. MS-QMA identified: (i) most SCAs if combined with a Y chromosome test; (ii) locus-specific XCI skewing towards the hypomethylated state in FM females; and (iii) skewed XCI towards the hypermethylated state in SCA with 3 or more X chromosomes, and in 5% of the 47,XXY individuals. MS-QMA output also showed significant correlation with the EpiTYPER reference method in FM males and females (P < 0.0001) and SCAs (P < 0.05). In conclusion, we demonstrate use of MS-QMA to quantify skewed XCI in two applications with diagnostic utility

    Polype antrochoanal de l’enfant

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    Le polype antrochoanal ou polype de killian est une nĂ©oformation bĂ©nigne dont l’origine est le sinus maxillaire et qui touche avec prĂ©dilection l’enfant et l’adulte jeune.Objectif : Le but de ce travail est de prĂ©ciser les caractĂ©ristiques du polype de killian chez l’enfant et d’évaluer les rĂ©sultats du traitement endoscopique.Patients et MĂ©thodes : Il s’agit d’une Ă©tude rĂ©trospective Ă  propos de 35 cas de polype antrochoanal opĂ©rĂ©s sur une pĂ©riode de 14 ans.RĂ©sultats : L’ñge moyen de nos malades Ă©tait de 13,2 ans. Il a Ă©tĂ© notĂ© une prĂ©dominance masculine. Tous nos patients n’avaient pas d’antĂ©cĂ©dants allergiques. L’obstruction nasale Ă©tait le maitre symptĂŽme. Six patients ont prĂ©sentĂ© une Ă©pistaxis. Le diagnostic du polype  antrochoanal Ă©tait Ă©voquĂ© sur des constatations endoscopiques et radiologiques. Tous nos patients ont bĂ©nĂ©ficiĂ© d’une mĂ©atotomie moyenne par voie endonasale associĂ©e Ă  une trĂ©panation de la fosse canine dans deux cas. Nous avons notĂ© 5 cas de rĂ©cidives dont la reprise Ă©tait par voie endoscopique associĂ©e Ă  une trĂ©panation de la fosse canine.Conclusion : Le taux de rĂ©cidive du polype de killian est plus important dans la population pĂ©diatrique. Le risque de rĂ©cidive dĂ©pend de deux facteurs essentiels : la technique chirurgicale qui doit ĂȘtre adaptĂ©e au cas par cas et le dĂ©lai diagnostique et thĂ©rapeutique qui doit ĂȘtre prĂ©coce avant l’apparition d’une rhino sinusite secondaire rendant la chirurgie difficile.Mots clĂ©s : polype antrochoanal, enfants, chirurgie endoscopique, rĂ©cidive

    Otospongiose : a propos de 149 cas

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    Introduction : L’otospongiose est une ostĂ©odystrophie de la capsule otique se traduisant par une surditĂ© de transmission ou plus rarement une surditĂ© mixte d’apparition progressive. Le but de notre travail est d’analyser les caractĂ©ristiques épidĂ©miologiques, cliniques, paracliniques et comparer les rĂ©sultats en fonction de l’ñge, du stade de l’ostĂ©odystrophie, de la technique chirurgicale et de la prothĂšse.Patients et mĂ©thodes : notre Ă©tude est rĂ©trospective portant sur 124 patients (149 oreilles) colligĂ©s sur une pĂ©riode de 9 ans (2000-2008).RĂ©sultats : notre population a comportĂ© 86 femmes et 38 hommes. La moyenne d’ñge Ă  l’intervention Ă©tait de 39,82 ans. La surditĂ© Ă©tait bilatĂ©rale dans 61,3% des cas et unilatĂ©rale dans 38,3%. Les seuils moyens prĂ©opĂ©ratoires de la conduction osseuse et aĂ©rienne Ă©taient respectivement de 17,33 dB et 52,52 dB, le rinne moyen Ă©tait de 35,19 dB. La tomodensitomĂ©trie a Ă©tĂ© rĂ©alisĂ©e chez 63 patients. On a rĂ©alisĂ© 21 platinectomie totale, 24 platinectomie partielle et 101 platinotomie calibrĂ©e. Selon la classification de Portmann, on a trouvĂ© une rĂ©partition sensiblement Ă©gale entre les stades II, III et IV. On a utilisĂ© un piston tĂ©flon 6/10 mm dans 119 cas et 4/10 mm dans 27 cas. Le rinne moyen postopĂ©ratoire était de 15,95 dB. a 1 an, le rinne Ă©tait de 14,81 dB avec un rĂ©sultat satisfaisant de 94,2%.Conclusion : Il ressort de notre travail que certains facteurs semblent prĂ©dictifs de bons rĂ©sultats et qui sont : le sexe fĂ©minin, l’ñge <50 ans, le stade chirurgical< stade IV, la platinotomie, et le piston 0,4 mm.Mots clĂ©s : otospongiose, conduction osseuse, conduction aĂ©rienne, platinotomie, platinectomie.Objective : Otosclerosis is a common disorder of the otic capsule characterized by the presence of a progressive conductive or rarely mixed hearing loss. The aims of this study were to analyses the epidemiologic, clinical, paraclinical characteristic and compare our results according to age, stage, surgical technique and prosthesis. Patients et mĂ©thodes : Our study is retrospective about 124 patients (149 ears) in the period of 9 years (2000-2008).Results: Our population included 86 female and 38 male patients. mean age at intervention time was 39,82 years. The hearing loss was bilateral in 61,3% of cases and unilateral in 38,3%. The bone and air conduction threshold was 17.33 dB and 52,52 dB, the air-bone gap was 35,19 dB. The CT scan was realized in 63 patients. We have realized 21stapedectomy, 24 partial stapedectomy and 101 stapedotomy. In accordance with Portmann classification, the distribution between II, III and IV stages was almost equal. We used 6/10 mm Teflon piston prosthesis in 119 cases and 4/10 mm in 27 cases. The postoperative air-bone gap was 15,95 dB. after 1 year, the air-bone gap was 14,81 dB with a satisfying results in 94,2%.Conclusion: it seems that some factors are predictive for good results like a female sex, age<50 years, stage< stage IV, platinotomy and piston 4/10 mm.Keyswords : otosclerosis, bone conduction, air conduction, stapedectomy, stapedotom

    PathGAN: visual scanpath prediction with generative adversarial networks

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    “This is a post-peer-review, pre-copyedit version of an article published in: Computer Vision – ECCV 2018 Workshops. The final authenticated version is available online at: http://dx.doi.org/10.1007/978-3-030-11021-5_25”.We introduce PathGAN, a deep neural network for visual scanpath prediction trained on adversarial examples. A visual scanpath is defined as the sequence of fixation points over an image defined by a human observer with its gaze. PathGAN is composed of two parts, the generator and the discriminator. Both parts extract features from images using off-the-shelf networks, and train recurrent layers to generate or discriminate scanpaths accordingly. In scanpath prediction, the stochastic nature of the data makes it very difficult to generate realistic predictions using supervised learning strategies, but we adopt adversarial training as a suitable alternative. Our experiments prove how PathGAN improves the state of the art of visual scanpath prediction on the iSUN and Salient360! datasets.Peer ReviewedPostprint (author's final draft

    Les osteomes des sinus de la face

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    Introduction : Le but de notre travail est prĂ©ciser le profil Ă©pidĂ©mio-clinique de cette pathologie, l’apport de l’imagerie dans le diagnostic, et discuter les modalitĂ©s de l’exĂ©rĂšse chirurgicale et l’apport de la voie endoscopique.Patients et mĂ©thode : il s’agit d’une Ă©tude rĂ©trospective de 18 patients porteurs d’ostĂ©omes des sinus paranasaux opĂ©rĂ©s entre 1993 Ă  2010. Ont Ă©tĂ© exclus les patients non opĂ©rĂ©s et les malades perdus de vue.RĂ©sultats : il s’agit de 18 patients porteurs d’un ostĂ©ome symptomatique des sinus de la face, d’ñge moyen 40 ans, sex ratio 0,38. La localisation la plus frĂ©quente Ă©tait le sinus frontal dans 55.5% des cas. Le traitement chirurgical Ă©tait de mise pour les patients symptomatiques. La voie endonasale Ă©tait indiquĂ©e dans 6 cas.la rĂ©cidive a intĂ©ressĂ© deux patients (11%) ayant un ostĂ©ome frontal et fronto-ethmoĂŻdal. Pour le reste des malades l’évolution Ă©tait favorable avec un recul moyen de 36 mois.Conclusion : L’ostĂ©ome des sinus paranasaux reste longtemps asymptomatique mais peut se compliquer par extension orbitaire ou cĂ©rĂ©brale. L’abord endonasal a permis d’amĂ©liorer la prise en charge.Mots clĂ©s : OstĂ©ome, sinus de la face, tomodensitomĂ©trie, chirurgie, voie endonasaleObjective : Lymph node infection is the most frequent localization of extrapulmonary tuberculosis. The treatment does not make general agreement. The aim of this study is to specify, from a review of the literature, the different ways of antimicrobial treatment and the indications of surgery.Patients and methods : il is about a retrospective study including 18 patients with paranasal sinus osteomas operated between 1993 and 2010. Were excluded unoperated and lost patients.Results : in this group of 18 patients with symptomatic sinus osteoma of the face, the mean age was 40 years, sex ratio was 0.38. the frontal sinus was the most affected, 55.5% of cases. Surgical treatment was set for symptomatic patients. The endonasal route was indicated in 6 cases. Recurrence was observed in two patients (11%) having a frontal osteoma and fronto-ethmoid. Outcomes were favorable in the remaining patients, mean follow-up was 36 months.Conclusion: Paranasal sinuses osteoma is a long asymptomatic tumor, but it may be complicated with orbital extending or stroke. Endonasal approach contributed to improve the treatment.Keyswords : Osteoma, paranasal sinus, computed tomography, surgery, endonasal approac

    Microglial autophagy-associated phagocytosis is essential for recovery from neuroinflammation

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    Multiple sclerosis (MS) is a leading cause of incurable progressive disability in young adults caused by inflammation and neurodegeneration in the central nervous system (CNS). The capacity of microglia to clear tissue debris is essential for maintaining and restoring CNS homeostasis. This capacity diminishes with age, and age strongly associates with MS disease progression, although the underlying mechanisms are still largely elusive. Here, we demonstrate that the recovery from CNS inflammation in a murine model of MS is dependent on the ability of microglia to clear tissue debris. Microglia-specific deletion of the autophagy regulator Atg7, but not the canonical macroautophagy protein Ulk1, led to increased intracellular accumulation of phagocytosed myelin and progressive MS-like disease. This impairment correlated with a microglial phenotype previously associated with neurodegenerative pathologies. Moreover, Atg7-deficient microglia showed notable transcriptional and functional similarities to microglia from aged wild-type mice that were also unable to clear myelin and recover from disease. In contrast, induction of autophagy in aged mice using the disaccharide trehalose found in plants and fungi led to functional myelin clearance and disease remission. Our results demonstrate that a noncanonical form of autophagy in microglia is responsible for myelin degradation and clearance leading to recovery from MS-like disease and that boosting this process has a therapeutic potential for age-related neuroinflammatory conditions.Swedish Research CouncilSwedish Brain FoundationSwedish Association for Persons with Neurological DisabilitiesStockholm County Council (ALF project)AstraZeneca (AstraZeneca-Science for Life Laboratory collaboration)European Union Horizon 2020/European Research Council Consolidator Grant (Epi4MS)Knut and Alice Wallenbergs FoundationMargeretha af Ugglas FoundationAlltid Litt SterkereFoundation of Swedish MS researchNEURO SwedenKarolinska InstitutetAccepte

    Proposal of an extended t-J Hamiltonian for high-Tc cuprates from ab initio calculations on embedded clusters

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    A series of accurate ab initio calculations on Cu_pO-q finite clusters, properly embedded on the Madelung potential of the infinite lattice, have been performed in order to determine the local effective interactions in the CuO_2 planes of La_{2-x}Sr_xCuO_4 compounds. The values of the first-neighbor interactions, magnetic coupling (J_{NN}=125 meV) and hopping integral (t_{NN}=-555 meV), have been confirmed. Important additional effects are evidenced, concerning essentially the second-neighbor hopping integral t_{NNN}=+110meV, the displacement of a singlet toward an adjacent colinear hole, h_{SD}^{abc}=-80 meV, a non-negligible hole-hole repulsion V_{NN}-V_{NNN}=0.8 eV and a strong anisotropic effect of the presence of an adjacent hole on the values of the first-neighbor interactions. The dependence of J_{NN} and t_{NN} on the position of neighbor hole(s) has been rationalized from the two-band model and checked from a series of additional ab initio calculations. An extended t-J model Hamiltonian has been proposed on the basis of these results. It is argued that the here-proposed three-body effects may play a role in the charge/spin separation observed in these compounds, that is, in the formation and dynamic of stripes.Comment: 24 pages, 4 figures, submitted to Phys. Rev.
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