Effect of new sealing treatments on corrosion fatigue lifetime of anodized 2024 aluminium alloy

The effect of two sealing processes, i.e. an usual hydrothermal sealing and an innovating sealing process called (B1 + B2), on fatigue behavior of anodized AA2024 was studied in air for as prepared and pre-corroded samples. Pre-corrosion exposure corresponded to salt-spray tests or continuous immersions. For salt-spray tests, the best corrosion resistance was related to the (B1+B2) sealing and, for continuous immersions, to the hydrothermal sealing. Fatigue life tests in air on pre-corroded samples revealed that anodized samples presented a decrease in fatigue life more pronounced than anodized and sealed samples in relation with a lower corrosion resistance; fatigue crack initiation was localized on pits issued from the degreasing and pickling steps. Independent of the sealing process, the fatigue behavior of the anodized and sealed samples depended on the pre-corrosion exposure. Corrosion fatigue tests induced an additional decrease in fatigue life for both sealing treatments. Crack initiation occurred preferentially on pits issued from degreasing and pickling but also on pits issued from interaction between cyclic loading and corrosive media, in relation with amechanical damage of the sealed anodic film. The differences in sealed layer morphology could explain the difference in fatigue resistance between the sealed anodic films

Immunogenicity and Safety of Beta-Adjuvanted Recombinant Booster Vaccine

International audienc

Neutralizing antibodies against SARS-CoV-2 variants following mRNA booster vaccination in adults older than 65 years

Immune response induced by COVID-19 vaccine booster against delta and omicron variants was assessed in 65 adults (65-84 years old) early aftesr a first booster dose. An increase in SARS-CoV-2 neutralizing antibodies was shown in individuals not previously infected without evidence of an age-related effect, with lower increase in those infected before a single dose of primary vaccination. Of note, humoral response was observed only starting from the 5th day after the boost

ABO blood types and SARS-CoV-2 infection assessed using seroprevalence data in a large population-based sample: the SAPRIS-SERO multi-cohort study

International audienceAbstract ABO blood type has been reported as a potential factor influencing SARS-CoV-2 infection, but so far mostly in studies that involved small samples, selected population and/or used PCR test results. In contrast our study aimed to assess the association between ABO blood types and SARS-CoV-2 infection using seroprevalence data (independent of whether or not individuals had symptoms or sought for testing) in a large population-based sample. Our study included 67,340 French participants to the SAPRIS-SERO multi-cohort project. Anti-SARS-CoV-2 antibodies were detected using ELISA (targeting the proteins spike (S) and nucleocapsid (NP)) and seroneutralisation (SN) tests on dried blood spots collected in May–November 2020. Non-O individuals (and especially types A and AB) were more likely to bear anti SARS-CoV-2 antibodies (ELISA-S, 2964 positive cases: OR non-Ovs.O = 1.09[1.01–1.17], OR Avs.O = 1.08[1.00–1.17]; ELISA-S/ELISA-NP/SN, 678 triple positive cases: OR non-Ovs.O = 1.19 [1.02–1.39], OR Avs.O = 1.19[1.01–1.41], OR ABvs.O = 1.43[1.01–2.03]). Hence, our results provided additional insights into the dynamic of SARS-CoV-2 infection, highlighting a higher susceptibility of infection for individuals of blood types A and AB and a lesser risk for blood type O

Estimating SARS-CoV-2 infection probabilities with serological data and a Bayesian mixture model

International audienceThe individual results of SARS-CoV-2 serological tests measured after the first pandemic wave of 2020 cannot be directly interpreted as a probability of having been infected. Plus, these results are usually returned as a binary or ternary variable, relying on predefined cut-offs. We propose a Bayesian mixture model to estimate individual infection probabilities, based on 81,797 continuous anti-spike IgG tests from Euroimmun collected in France after the first wave. This approach used serological results as a continuous variable, and was therefore not based on diagnostic cut-offs. Cumulative incidence, which is necessary to compute infection probabilities, was estimated according to age and administrative region. In France, we found that a “negative” or a “positive” test, as classified by the manufacturer, could correspond to a probability of infection as high as 61.8% or as low as 67.7%, respectively. “Indeterminate” tests encompassed probabilities of infection ranging from 10.8 to 96.6%. Our model estimated tailored individual probabilities of SARS-CoV-2 infection based on age, region, and serological result. It can be applied in other contexts, if estimates of cumulative incidence are available

Neutralizing antibodies against SARS-CoV-2 variants following mRNA booster vaccination in adults older than 65 years

International audienceImmune response induced by COVID-19 vaccine booster against delta and omicron variants was assessed in 65 adults (65–84 years old) early aftesr a first booster dose. An increase in SARS-CoV-2 neutralizing antibodies was shown in individuals not previously infected without evidence of an age-related effect, with lower increase in those infected before a single dose of primary vaccination. Of note, humoral response was observed only starting from the 5th day after the boost