Spontaneous osteo-dural fistulae of petrous bone posterior wall

SummaryObjectiveTo raise awareness of the possibility of spontaneous temporal bone cerebrospinal fistula in case of clear retrotympanic effusion.Case reportA 63-year-old man with no particular history presented with unilateral spontaneous right retrotympanic clear effusion. CT found defects in the posterior part of the right temporal bone, in contact with arachnoid granulations, with no other visible abnormalities.Discussion/ConclusionUnilateral clear retrotympanic effusion in an adult subject should, apart from serous otitis media, suggest possible cerebrospinal fistula. In the absence of otologic or traumatic history, arachnoid granulation is one possible etiology, inducing spontaneous cerebrospinal fluid leakage when facing the temporal bone. Diagnosis is suggested by bone defects in the tegmen tympani or posterior wall of the temporal bone on CT, with the adjacent mastoid cavities filled with fluid. Pneumococcal vaccination and early surgical repair of the fistula should be performed to avoid neuromeningeal infection

Solution-Processable Graphene Oxide as an Efficient Hole Injection Layer for High Luminance Organic Light-Emitting Diodes

The application of solution-processable graphene oxide (GO) as hole injection layer in organic light-emitting diodes (OLEDs) is demonstrated. High luminance of over 53,000 cd m-2 is obtained at only 10 V. The results will unlock a route of applying GO in flexible OLEDs and other electrode applications.Comment: 14 pages, 3 figures, 1 tabl

Annealing effect on the structural, magnetic and transport properties in the CoxCu1-x granular alloys with 0.20 ≤ x ≤ 0.25 prepared by the ion-beam sputtering technique

We have studied the transport and magnetic properties of a metallic granular CoxCu1-x system, with 0.2≤x≤0.25, prepared by using an ion-beam sputtering technique. Giant magnetoresistance (GMR) has been observed for the all studied concentration with the average amplitude around 2%. at 300K. The maximum value has been observed for Co21Cu79 granular alloy after annealing at 450°C for 2h. Above this concentration the MR decreases which is attributed to the percolation effect, which causes a concurrent reduction in magnetic coercivity. The variation of magnetic and transport properties with the concentration and annealing time is discussed.We have studied the transport and magnetic properties of a metallic granular CoxCu1-x system, with 0.2≤x≤0.25, prepared by using an ion-beam sputtering technique. Giant magnetoresistance (GMR) has been observed for the all studied concentration with the average amplitude around 2%. at 300K. The maximum value has been observed for Co21Cu79 granular alloy after annealing at 450°C for 2h. Above this concentration the MR decreases which is attributed to the percolation effect, which causes a concurrent reduction in magnetic coercivity. The variation of magnetic and transport properties with the concentration and annealing time is discussed

L'ombre d'un doute ? Interactions perceptivo-motrices lors de tâches de close-shadowing auditive et audio-visuelles

International audienceOne classical argument in favor of a functional role of the motor system in speech perception comes from the close shadowing task in which a subject has to identify and to repeat as quickly as possible an auditory speech stimulus. The fact that close shadowing can occur very rapidly and much faster than manual identification of the speech target is taken to suggest that perceptually-induced speech representations are already shaped in a motor-compatible format. Another argument is provided by audiovisual interactions often interpreted as referring to a multisensory-motor framework. In this study, we attempted to combine these two paradigms by testing whether the visual modality could speed motor response in a close-shadowing task. To this aim, both oral and manual responses were evaluated during the perception of auditory and audio-visual speech stimuli, clear or embedded in white noise. Overall, oral responses were much faster than manual ones, but it also appeared that they were less accurate in noise, which suggests that motor representations evoked by the speech input could be rough at a first processing stage. In the presence of acoustic noise, the audiovisual modality led to both faster and more accurate responses than the auditory modality. No interaction was however observed between modality and response. Altogether, these results are interpreted within a two-stage sensory-motor framework, in which the auditory and visual streams are integrated together and with internally generated motor representations before a final decision may be available.Un argument classique en faveur des théories motrices de la perception de la parole provient du paradigme de " close-shadowing " (répétition rapide). Le fait que cette tâche de close-shadowing entraîne des réponses orales bien plus rapides qu'en réponses manuelles suggère en effet un codage des représentations perceptives dans un format moteur, compatible avec une réponse orale. Un autre argument est apporté par les interactions audio-visuelles lors de la perception de parole, souvent interprétées en référence à un couplage fonctionnel entre audition, vision et motricité. Dans cette étude, nous avons combiné ces deux paradigmes de manière à tester si la modalité visuelle pouvait induire des réponses motrices plus rapides lors d'une tâche de close-shadowing. Pour ce faire, différentes tâches de catégorisation orale et manuelle de stimuli de parole présentés auditivement ou audio-visuellement, en présence ou non d'un bruit blanc, ont été réalisées. De manière générale, les réponses orales ont été plus rapides que les réponses manuelles, mais aussi moins précises, notamment dans le bruit, ce qui suggère que la représentation motrice induite par la stimulation pourrait être peu précise dans un premier niveau de traitement. En présence d'un bruit acoustique, la modalité audiovisuelle s'est avérée à la fois plus rapide et plus précise que la modalité auditive. Aucune interaction entre le mode de réponse et la modalité de présentation des stimuli n'a cependant été observée. Nous interprétons l'ensemble de ces résultats dans un cadre théorique proposant l'existence de boucles perceptivo-motrices, dans lesquelles les entrées auditives et visuelles seraient intégrées et reliées à la génération interne de représentations motrices préalablement au processus final de décision

L'ombre d'un doute ? Interactions perceptivo-motrices lors de tâches de close-shadowing auditive et audio-visuelles

International audienceOne classical argument in favor of a functional role of the motor system in speech perception comes from the close shadowing task in which a subject has to identify and to repeat as quickly as possible an auditory speech stimulus. The fact that close shadowing can occur very rapidly and much faster than manual identification of the speech target is taken to suggest that perceptually-induced speech representations are already shaped in a motor-compatible format. Another argument is provided by audiovisual interactions often interpreted as referring to a multisensory-motor framework. In this study, we attempted to combine these two paradigms by testing whether the visual modality could speed motor response in a close-shadowing task. To this aim, both oral and manual responses were evaluated during the perception of auditory and audio-visual speech stimuli, clear or embedded in white noise. Overall, oral responses were much faster than manual ones, but it also appeared that they were less accurate in noise, which suggests that motor representations evoked by the speech input could be rough at a first processing stage. In the presence of acoustic noise, the audiovisual modality led to both faster and more accurate responses than the auditory modality. No interaction was however observed between modality and response. Altogether, these results are interpreted within a two-stage sensory-motor framework, in which the auditory and visual streams are integrated together and with internally generated motor representations before a final decision may be available.Un argument classique en faveur des théories motrices de la perception de la parole provient du paradigme de " close-shadowing " (répétition rapide). Le fait que cette tâche de close-shadowing entraîne des réponses orales bien plus rapides qu'en réponses manuelles suggère en effet un codage des représentations perceptives dans un format moteur, compatible avec une réponse orale. Un autre argument est apporté par les interactions audio-visuelles lors de la perception de parole, souvent interprétées en référence à un couplage fonctionnel entre audition, vision et motricité. Dans cette étude, nous avons combiné ces deux paradigmes de manière à tester si la modalité visuelle pouvait induire des réponses motrices plus rapides lors d'une tâche de close-shadowing. Pour ce faire, différentes tâches de catégorisation orale et manuelle de stimuli de parole présentés auditivement ou audio-visuellement, en présence ou non d'un bruit blanc, ont été réalisées. De manière générale, les réponses orales ont été plus rapides que les réponses manuelles, mais aussi moins précises, notamment dans le bruit, ce qui suggère que la représentation motrice induite par la stimulation pourrait être peu précise dans un premier niveau de traitement. En présence d'un bruit acoustique, la modalité audiovisuelle s'est avérée à la fois plus rapide et plus précise que la modalité auditive. Aucune interaction entre le mode de réponse et la modalité de présentation des stimuli n'a cependant été observée. Nous interprétons l'ensemble de ces résultats dans un cadre théorique proposant l'existence de boucles perceptivo-motrices, dans lesquelles les entrées auditives et visuelles seraient intégrées et reliées à la génération interne de représentations motrices préalablement au processus final de décision

Control of defect-mediated tunneling barrier heights in ultrathin MgO films

The impact of oxygen vacancies on local tunneling properties across rf-sputtered MgO thin films was investigated by optical absorption spectroscopy and conducting atomic force microscopy. Adding O$_2$ to the Ar plasma during MgO growth alters the oxygen defect populations, leading to improved local tunneling characteristics such as a lower density of current hotspots and a lower tunnel current amplitude. We discuss a defect-based potential landscape across ultrathin MgO barriers.Comment: 4 pages, 4 figure