Evolution of defects in titanium grade 2 under Ti2+ion irradiation

The complexity and diversity of microstructure involved in titanium alloysmakeit rather difficult to quantitatively describe defect evolution due to irradiation. This paper focusesondefect evolutions of commercially pure titanium grade 2 under Ti2+ ion irradiation considering the effect of dose (0.6 and 3 dpa), temperature (300°C and 430°C) and flux (15:1 ratio). An irradiation damage profile was predicted using SRIM software to obtain a homogeneous damage on at least 500 nm depth for TEM observations and simulated using JANNUS-Saclay facility. The details regarding the quantification methodologies of the defects from dark field images are provided, as are the origins of the associated uncertainties. In addition to a tangled dislocation network, presence of the -type and -component loops is observed. The latter was scarcely reported in the literature in the case of titanium alloys. At low temperature, the size distribution of the -type dislocation loops remained similar regardless of the dose and flux whereas these parameters have highly influence at 430°C. A widening of the size distribution and an increase of the threshold incubation dose (TID) was noted with the temperature. In the case of the -component loops, it was shown that the nucleation occurred in spite of the 0.6 dpa low dose

The role of the amygdala in the perception of positive emotions: an “intensity detector”

International audienc

analyse expérimentale de la réalisation de microcavités sur substrats polymères thermoplastiques par le procédé de roll embossing

de nouveaux developpements experimentaux ont ete realises afin de mettre au point le procede de roll embossing pour la realisation de microstructure en continu pour des polymeres et des polymeres charges. des caracterisations rheologiques ont ete realisees pour optimiser les parametres procedes. les resultats obtenus par MMB conduisent a l'obtention de composants sans defauts. des comparaisons geometriques et topographiques entre les repliques et les empreintes du moule montrent un bon remplissage des composants au dela de 200°

Evolution of defects in Ti6-4 under Ti2+ ion irradiation: Focus on radiation-induced precipitates

Ion irradiations on the Ti6-4 titanium alloy were conducted at the JANNUS French platform in two different conditions of temperatures, doses and fluxes, to simulate neutron irradiation damage. Quantification of defects and chemical microanalyses were carried out thanks to Transmission Electron Microscopy and Atom Probe Tomography. -type loops and radiation induced precipitates (a vanadium-rich β BCC phase) were observed for both irradiation temperatures. During an irradiation at 300 °C, there was no notable influence of the dose and flux for the considered doses and fluxes ranges on the -type defects. The influence of raising the irradiation temperature up to 430 °C was a lowering of their density and an increase of their mean diameter for both defects. In addition, a lower flux seemed to enhance this temperature effect. These phenomena were very significant for precipitates whereas it appeared very modest for -type loops. The probable mechanism to explain the distribution of vanadium-rich β precipitates inside the α phase is the heterogeneous nucleation. The nucleation is dominated by the Radiation Induced Segregation (RIS) phenomenon at 430 °C and could be dominated by the mechanism of vanadium-rich clusters formation by ballistic effects in the cascades at 300 °C

The Other Press, February 28, 1977

BACKGROUND: In the adult population with newly diagnosed chronic myeloid leukemia (CML), variant translocations are usually not considered to be impairing the prognosis, whereas some additional cytogenetic abnormalities (ACAs) are associated with a negative impact on survival. Because of the rarity of CML in the pediatric population, such abnormalities have not been investigated in a large group of children with CML. METHODS: The prognostic relevance of variant t(9;22) and ACAs at diagnosis was assessed in 301 children with CML in the chronic phase who were enrolled in the International Registry for Chronic Myeloid Leukemia in Children and Adolescents. RESULTS: Overall, 19 children (6.3%) presented with additional cytogenetic findings at diagnosis: 5 children (1.7%) had a variant t(9;22) translocation, 13 children (4.3%) had ACAs, and 1 had both. At 3 years, for children with a classic translocation, children with ACAs, and children with a variant t(9;22) translocation who were treated with imatinib as frontline therapy, the probability of progression-free survival (PFS) was 95% (95% confidence interval [CI], 91%-97%), 100%, and 75% (95% CI, 13%-96%), respectively, and the probability of overall survival (OS) was 98% (95% CI, 95%-100%), 100% (95% CI, 43%-98%), and 75% (95% CI, 13%-96%), respectively. No statistical difference was observed between the patients with classic cytogenetic findings and those with additional chromosomal abnormalities in terms of PFS and OS. CONCLUSIONS: In contrast to adults with CML, additional chromosomal abnormalities observed at diagnosis do not seem to have a significant prognostic impact

Field Effectiveness of Pandemic and 2009-2010 Seasonal Vaccines against 2009-2010 A(H1N1) Influenza: Estimations from Surveillance Data in France

BACKGROUND: In this study, we assess how effective pandemic and trivalent 2009-2010 seasonal vaccines were in preventing influenza-like illness (ILI) during the 2009 A(H1N1) pandemic in France. We also compare vaccine effectiveness against ILI versus laboratory-confirmed pandemic A(H1N1) influenza, and assess the possible bias caused by using non-specific endpoints and observational data. METHODOLOGY AND PRINCIPAL FINDINGS: We estimated vaccine effectiveness by using the following formula: VE  =  (PPV-PCV)/(PPV(1-PCV)) × 100%, where PPV is the proportion vaccinated in the population and PCV the proportion of vaccinated influenza cases. People were considered vaccinated three weeks after receiving a dose of vaccine. ILI and pandemic A(H1N1) laboratory-confirmed cases were obtained from two surveillance networks of general practitioners. During the epidemic, 99.7% of influenza isolates were pandemic A(H1N1). Pandemic and seasonal vaccine uptakes in the population were obtained from the National Health Insurance database and by telephonic surveys, respectively. Effectiveness estimates were adjusted by age and week. The presence of residual biases was explored by calculating vaccine effectiveness after the influenza period. The effectiveness of pandemic vaccines in preventing ILI was 52% (95% confidence interval: 30-69) during the pandemic and 33% (4-55) after. It was 86% (56-98) against confirmed influenza. The effectiveness of seasonal vaccines against ILI was 61% (56-66) during the pandemic and 19% (-10-41) after. It was 60% (41-74) against confirmed influenza. CONCLUSIONS: The effectiveness of pandemic vaccines in preventing confirmed pandemic A(H1N1) influenza on the field was high, consistently with published findings. It was significantly lower against ILI. This is unsurprising since not all ILI cases are caused by influenza. Trivalent 2009-2010 seasonal vaccines had a statistically significant effectiveness in preventing ILI and confirmed pandemic influenza, but were not better in preventing confirmed pandemic influenza than in preventing ILI. This lack of difference might be indicative of selection bias

Etude d'un essai original de flexion-torsion 4 points et application a la modelisation du comportement des materiaux composites en contraintes complexes

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : TD 20421 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc