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Les potentiels évoqués vestibulaires myogéniques (PEVM) sont de plus en plus réalisés en pratique clinique courante chez des patients vertigineux ou rapportant une instabilité chronique. Ils sont complémentaires de la vidéonystagmographie et du « Video Head Impulse Test », et permettent d’apprécier la fonction otolithique des patients. Les PEVM sont des examens simples et reproductibles en l’absence de surdité de transmission préexistante. On distingue les PEVM cervicaux, explorant la fonction sacculaire et le nerf vestibulaire inférieur, des PEVM oculaires qui eux étudient la fonction utriculaire et le nerf vestibulaire supérieur. Ils permettent, en association avec les autres explorations vestibulaires, une aide diagnostique dans de nombreuses pathologies comme le syndrome de Minor, la maladie de Menière, la névrite vestibulaire, le schwannome vestibulaire ou l’aréflexie vestibulaire idiopathique. La réalisation de ces examens électrophysiologiques est importante à connaître pour interpréter correctement les réponses enregistrées afin de ne pas méconnaître un déficit de la fonction vestibulaire ou au contraire de conclure à tort à un déficit de cette fonction. Nous décrivons la réalisation de ces examens ainsi que les pièges à éviter. Enfin, nous rappelons les principaux résultats en fonction des pathologies ayant un retentissement sur la fonction vestibulaire.

The effects of different grades of carbon nanotubes on the curing of a typical epoxy resin (EPIKOTE™ resin 862 and EPIKURE™ curing agent W) were examined via differential scanning calorimetry. It was found that nanotubes could initiate cure at lower temperatures, while the overall curing process was slowed as evidenced by lower total heat of reaction and lower glass transition temperatures of the cured nanocomposites compared to neat epoxy. This finding is practically important as it is essential to have a consistent degree of cure when the properties of thermosets with nanoinclusions are compared to neat resins. It was also found that the inclusion of carbon nanotubes might induce the thermal degradation of epoxy composites at lower temperatures. Morphological analysis done with scanning electron microscopy revealed good dispersion of nanotubes within the epoxy matrix. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5248–5254, 2006

Concurrent radionecrosis within the spinal cord and the bone marrow at the same thoracic level was observed 8 years after localized therapeutic irradiation in a patient who had undergone repeated cycles of radiotherapy, glucocorticoid treatment, and chemotherapy for a non-Hodgkin's lymphoma. Mechanisms combining radiotoxic potentialization by glucocorticoids/alkylating agents and delayed radiation-induced vasculitis involving the common arterial pathways to the spinal cord and to the vertebrae were speculated to have acted in a synergistic way.

The aim was to coat mild steel with an electron conducting polymer in order to replace any possible electrochemical corrosion of the metal by another electrochemical reaction occurring on top of the film. In view of potential industrialization, electropolymerization of a water soluble monomer was studied. In most cases, this was achieved by oxidation, and the substrate had to be passivated. Polyaniline, was obtained in nitric acid solution. Films had a good structure but were brittle and powdery on the surface. Except on tin free steel, they were insulating. Polypyrrole was a better candidate. Prepared from a Na2SO4 solution, films were conductive, ensured good corrosion resistance of the substrate but they were brittle and adhesion to the substrate was not high. Furance, thiophene and iron substituted vinylpyridine complex were tried without success. Further, research should consider copolymerization of pyrrole with other monomers.

Examination by ESCA of passivation films on tinplate has cast doubt on the assumptions sometimes made that only Cr°; is left after extraction of the films with boiling 5M NaOH, and that the sole action of anodic oxidation in phosphate solution is dissolution of Cr°. Therefore, methods of estimating Cr°content based on these assumptions give results in excess of true values. The amount of chromium insoluble in boiling 5M NaOH increases after a short time at raised temperature or after storage, and this effect was shown by ESCA to be due to dehydration of hydroxides.Application of ESCA to fracture surfaces after detachment of lacquer showed that failure of adhesion occurred between the passivation film and the tin surface and that the growth of tin oxide could introduce a weak layer.