Single pulse avalanche robustness and repetitive stress ageing of SiC power MOSFETs

This paper presents an extensive electro-thermal characterisation of latest generation silicon carbide (SiC) Power MOSFETs under unclamped inductive switching (UIS) conditions. Tests are carried out to thoroughly understand the single pulse avalanche ruggedness limits of commercial SiC MOSFETs and assess their aging under repetitive stress conditions. Both a functional and a structural characterisation of the transistors is presented, with the aim of informing future device technology development for robust and reliable power system development

Pain Assessment In Students Who Cannot Self-Report: A Pilot Study

This is a pilot study in students who cannot self report pain due to intellectual disabilities

I-21 Current therapeutic guidelines in Duchenne Muscular Dystrophy to prolong life

Duchenne's myopathy is an X-linked disease with well defined evolutionary phases, characterized by degradation of the walking function, development of evolutive scoliosis and progressive decline of the respiratory function leading patients to premature death. In 1985 Y. Rideau in France carried out a new global therapeutic strategy for treatment of lower limb deformities, scoliosis deformity and progressive restrictive syndrome. The indication for surgery at the lower limbs is made very early, at the onset of the first signs of disease. The procedures are carried out at the same time and always bilaterally; they include: (i) hip section of superficial flexors; (ii) iliotibial band resection; (iii) subcutaneous tenotomy of semitendineous and gracilis; (iv) subcutaneous lengthening of Achilles tendons. In the post-operative period, the patient begins exercises of active and passive mobility in few days and after three weeks recovers his performances; ambulation will remain almost normal for several years. A comparison of two groups of patients, the first precociously operated on the lower limbs, the other one not operated, shows better performances in the operated group. The indications for surgical treatment of Duchenne scoliosis must be made after the loss of ambulation and not too late, to avoid the concurrent respiratory restrictive syndrome makes the patient inoperable. Over ten years ago, in Poitiers, a specific instrumentation for Duchenne scoliosis was created, providing for cylindrical rods fixed by peduncular screws at the sacro-lumbar level. On the dorso-lumbar level, the rod becomes flat to allow more flexibility of the trunk. The complications observed in a group of 55 patients operated for scoliosis, consisted in 2 cases of breaking of rods and 1 superficial infection. The surgery approach in DMD has the double aim to prolong the time of the autonomous ambulation and to avoid the evolution of scoliosis, limiting the harmful effects of the scoliosis on the respiratory function. However, the surgery alone is unable to prolong the life expectancy in these patients, without treating the restrictive respiratory syndrome, first by nasal ventilation and then by elective tracheotomy, essential for the survival of the patient

Metabolites of the new Caledonian sponge Cladocroce incurvata

The deep-water New Caledonian sponge #Cladocroce incurvata$ contains two "polyketide" metabolites. Cladocrocin A (1) appears to be derived from fatty acid with ethyl side chains, thus incorporating butyrate units. Cladocroic acid (2) is a straight chain fatty acid which incorporates a terminal enyne functionality and a cycloproprane ring directly attached to the carboxylic acid function. The structures were elucidated by interpretation of spectral data, and the cis stereochemistry of the cyclopropane ring in cladocroic acid (2) was derived after the synthesis of cis - and trans - 2, 3 - methanohexanoic acid models and nmr spectral comparisons. (Résumé d'auteur

Three-Dimensional Imaging and Numerical Reconstruction of Graphite/Epoxy Composite Microstructure Based on Ultra-High Resolution X-Ray Computed Tomography

A combined experimental and computational study aimed at high-resolution 3D imaging, visualization, and numerical reconstruction of fiber-reinforced polymer microstructures at the fiber length scale is presented. To this end, a sample of graphite/epoxy composite was imaged at sub-micron resolution using a 3D X-ray computed tomography microscope. Next, a novel segmentation algorithm was developed, based on concepts adopted from computer vision and multi-target tracking, to detect and estimate, with high accuracy, the position of individual fibers in a volume of the imaged composite. In the current implementation, the segmentation algorithm was based on Global Nearest Neighbor data-association architecture, a Kalman filter estimator, and several novel algorithms for virtualfiber stitching, smoothing, and overlap removal. The segmentation algorithm was used on a sub-volume of the imaged composite, detecting 508 individual fibers. The segmentation data were qualitatively compared to the tomographic data, demonstrating high accuracy of the numerical reconstruction. Moreover, the data were used to quantify a) the relative distribution of individual-fiber cross sections within the imaged sub-volume, and b) the local fiber misorientation relative to the global fiber axis. Finally, the segmentation data were converted using commercially available finite element (FE) software to generate a detailed FE mesh of the composite volume. The methodology described herein demonstrates the feasibility of realizing an FE-based, virtual-testing framework for graphite/fiber composites at the constituent level

(+/-)-Gelliusines A and B, two diastereomeric brominated tris-indole alkaloids from a deep water New Caledonian marine sponge (Gellius or Orina sp.)

Two new diastereomeric brominated tris-indole alkaloids occurring as enantiomeric pairs, (±)-gelliusine A (I) and its isomer (±)-gelliusine B, have been isolated from a deep water New Caledonian sponge (Gellius or Orina sp.), whose crude ext. exhibited cytotoxicity against KB cells. Their structures were elucidated by spectroscopic methods including one- and two-dimensional NMR spectroscopy. The major compd., I, which showed very weak cytotoxicity, proved to be active at the serotonin receptor

Carbapenem-resistant Pseudomonas aeruginosa with acquired bla(vim) metallo-beta-lactamase determinants, Italy.

6nonenoneROSSOLINI G.M.; RICCIO M.L.; CORNAGLIA G.; PAGANI L.; LAGATOLLA C.; SELAN L. AND FONTANA R.Rossolini, G. M.; Riccio, M. L.; Cornaglia, G.; Pagani, L.; Lagatolla, Cristina; Selan, L. AND FONTANA R