Influence of surface integrity induced by anodizing process on fatigue life of Ti-6Al-4V

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Influence of surface integrity induced by anodizing process on fatigue life of Ti-6Al-4V

International audienceno abstrac

Successful treatment with fumagillin of the first pediatric case of digestive microsporidiosis in a liver-kidney transplant

International audienceSuccessful treatment with fumagillin of the first pediatric case of digestive microsporidiosis in a liver-kidney transplant. Transpl Infect Dis 2013. All rights reserved Abstract: We report the first successful use, to our knowledge, of fumagillin alone in a pediatric patient to cure intestinal microsporidiosis in a liver-kidney transplanted child. Detection of Enterocytozoon bieneusi in stool became negative from the first post-therapeutic control, while digestive symptoms disappeared in 4 days. During a 9-month follow-up, polymerase chain reaction and direct examinations remained negative for microsporidia in her feces. No major undesirable effects were noted during the anti-microsporidial therapy

Hydrogen isotopic anomalies in extraterrestrial organic matter: role of cosmic ray irradiation and implications for UCAMMs

International audienceContext. Micrometeorites represent, at timescales shorter than a few million years, the dominant source of extraterrestrial matter at the surface of the Earth. Analyses of ultracarbonaceous micrometeorites recovered from Antarctica, known as UCAMMs reveal an exceptionally N-rich organic matter associated with spatially extended high D enrichments. Experiments show that this specific organic matter might have been formed in the outer solar system by energetic irradiation of N-rich icy surfaces.Aims. We experimentally investigate the hydrogen isotopic fractionation resulting from irradiation of normal and D-rich N2-CH4 ices by high energy ions, simulating the exposition to Galactic cosmic rays of icy bodies surfaces orbiting at large heliocentric distances.Methods. Films of N2-CH4 ices and a N2-CH4/CD4/N2-CH4 “sandwich” ice were exposed to 129Xe13+ ion beams at 92 and 88 MeV. The chemical evolution of the samples was monitored using in situ Fourier transform infrared spectroscopy. After irradiation, targets were annealed to room temperature. The solid residues of the whole process left after ice sublimation were characterized in situ by infrared spectroscopy, and the hydrogen isotopic composition measured ex situ by imaging secondary ion mass spectrometry at the sub-micron scale (NanoSIMS).Results. Irradiation leads to the formation of new molecules and radicals. After annealing, the resulting poly-HCN-like macro-molecular residue exhibits an infrared spectrum close to that of UCAMMs. The residue resulting from irradiation of N2-CH4 ices does not exhibit a significant deuterium enrichment comparable to that found in extraterrestrial organic matter. The residue formed by irradiation of D-rich ices shows the formation of isotopic heterogeneities with localised hotspots and an extended contribution likely due to the diffusion of the radiolytic products from the D-rich layer.Conclusions. These results show that high-energy cosmic ray irradiation does not induce the large hydrogen isotopic fractionation observed at small spatial scale in interplanetary organics. By contrast, large D/H ratio heterogeneities at the sub-micron spatial scale in extraterrestrial organic matter can result from isotopically heterogeneous ices mixtures (i.e. condensed with different D/H ratios), which were transformed into refractory organic matter upon irradiation

ON THE ORIGIN OF ORGANICS IN ULTRACARBONACEOUS ANTARCTIC MICROMETEORITES (UCAMMS), IRRADIATION OF N-RICH ICES IN THE OUTER SOLAR SYSTEM

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Lorsque l’enfant parait … ou l’histoire d’une infection congénitale solognote improbable

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