Effect of cerium concentration on corrosion resistance and polymerization of hybrid sol–gel coating on martensitic stainless steel

Stainless steels are increasingly used in the aeronautics field for the manufacture of structural parts. One of them, the X13VD martensitic stainless steel (X12CrNiMoV12-3), known for its good mechanical properties, has a poor corrosion resistance in confined or severe environments. In the past years, Cr(VI) based pre-treatments have been currently used for corrosion protection of different metals, however, they are toxic and due to environmental regulations, they will be definitely banned in a near future. Alternatives to replace Cr(VI) show advantages and drawbacks considering key properties such as: corrosion resistance, adhesion of coatings, fatigue resistance, durability and reliability. However, some of their possible alternatives show high potential. In this paper, a process was developed to improve the corrosion resistance of the martensitic stainless steel. Organic–inorganic hybrid coatings with different cerium concentrations were deposited onto stainless steel by sol–gel process. Corrosion resistance of the coatings was evaluated by electrochemical impedance measurements and it has been proved that cerium concentration of 0.01 M into hybrid coating was an optimal content. Adhesion tests were also carried out by "nanoscratchtest" to characterize the coatings mechanical properties as a function of cerium concentration but results do not clearly show the influence of cerium for the coating adhesion toward the substrate. To try to correlate with the electrochemical properties, liquid 29Si NMR spectroscopy was then performed to investigate hydrolysis and condensation reactions of sol–gel process, and by this method, it was demonstrated that for higher cerium concentration (>0.01 M) there is a modification of the chemical structure of the sol–gel network

Effect of cerium on structure modifications of a hybrid sol–gel coating, its mechanical properties and anti-corrosion behavior

An organic–inorganic hybrid coating was developed to improve the corrosion resistance of the aluminum alloy AA 2024-T3. Organic and inorganic coatings derived from glycidoxypropyltrimethoxysilane (GPTMS) and aluminum tri-sec-butoxide Al(OsBu)3, with different cerium contents, were deposited onto aluminum by dip-coating process. Corrosion resistance and mechanical properties were investigated by electrochemical impedance measurements and nano-indentation respectively. An optimal cerium concentration of 0.01 M was evidenced. To correlate and explain the hybrid coating performances in relation to the cerium content, NMR experiments were performed. It has been shown that when the cerium concentration in the hybrid is higher than 0.01 M there are important modifications in the hybrid structure that account for the mechanical properties and anti-corrosion behavior of the sol–gel coating

The Egyptian wheat cultivar Gemmeiza-12 is a source of resistance against the fungus <i>Zymoseptoria tritici</i>

Background: Wheat is one of the world’s most important cereal crops. However, the fungal pathogen Zymoseptoria tritici can cause disease epidemics, leading to reduced yields. With climate change and development of new agricultural areas with suitable environments, Z. tritici may advance into geographical areas previously unaffected by this pathogen. It is currently unknown how Egyptian wheat will perform in the face of this incoming threat. This project aimed to assess the resistance of Egyptian wheat germplasm to Z. tritici, to identify cultivars with high levels of resistance and characterise the mechanism(s) of resistance present in these cultivars. Results: Eighteen Egyptian wheat cultivars were screened against two Z. tritici model isolates and exhibited a wide spectrum of responses. This ranged from resistance to complete susceptibility to one or both isolates tested. The most highly resistant cultivars from the initial screen were then tested under two environmental conditions against modern UK field isolates. Disease levels under UK-like conditions were higher, however, symptom development on the cultivar Gemmeiza-12 was noticeably slower than on other Egyptian wheats. The robustness of the resistance shown by Gemmeiza-12 was confirmed in experiments mimicking Egyptian environmental conditions, where degree of Z. tritici infection was lower. The Kompetitive allele-specific PCR (KASP) diagnostic assay suggested the presence of an Stb6 resistant allele in several Egyptian wheats including Gemmeiza-12. Infection assays using the IPO323 WT and IPO323ΔAvrStb6 mutant confirmed the presence of Stb6 in several Egyptian cultivars including Gemmeiza-12. Confocal fluorescence microscopy demonstrated that growth of the IPO323 strain is blocked at the point of stomatal penetration on Gemmeiza-12, consistent with previous reports of Stb gene mediated resistance. In addition to this R-gene mediated resistance, IPO323 spores showed lower adherence to leaves of Gemmeiza-12 compared to UK wheat varieties, suggesting other aspects of leaf physiology may also contribute to the resistance phenotype of this cultivar. Conclusion: These results indicate that Gemmeiza-12 will be useful in future breeding programs where improved resistance to Z. tritici is a priority

The impact of European embryonic stem cell patent decisions on research strategies

No description supplie

Int J Environ Res Public Health

This scoping study aims to explore the relationships between urban green spaces (UGSs) and the onset, remission and recovery of cancer. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping reviews (protocol published in 2018). Eligibility criteria for papers were: (1) to be concerned with UGSs, (2) reporting effects of UGSs on cancer-related outcomes including direct or indirect measures, (3) reporting randomized controlled trials, prospective cohort studies, case studies, observational studies, non-comparative studies, (4) in English or French. The search covered primary studies in the published and unpublished (grey) literatures searching by hand and electronic databases (MEDLINE, Green File, Cumulative Index to Nursing and Allied Health Literature and ScienceDirect). Among 1703 records screened by two reviewers independently, 29 were included for qualitative synthesis. We classify the cancers concerned and the effects reported i.e., protective effect, risk or without association. The most investigated cancers are bladder, breast and lung cancer. Our study also identified contributing factors and their mediating effects between UGSs and cancer. Even though the strength of the evidence of the associations between UGSs and cancer is still weak due to the low number of studies and their design, results highlight the wide variety of possible mediating factors between the use of green spaces and cancer occurrence, remission and/or prevention. Knowledge gaps and future research perspectives should be oriented to qualitative research on protective factors with an attention to equity in UGS access and use

Wheat receptor-kinase-like protein Stb6 controls gene-for-gene resistance to fungal pathogen Zymoseptoria tritici

Deployment of fast-evolving disease-resistance genes is one of the most successful strategies used by plants to fend off pathogens. In gene-for-gene relationships, most cloned disease-resistance genes encode intracellular nucleotide-binding leucine-rich-repeat proteins (NLRs) recognizing pathogensecreted isolate-specific avirulence (Avr) effectors delivered to the host cytoplasm. This process often triggers a localized hypersensitive response, which halts further disease development. Here we report the map-based cloning of the wheat Stb6 gene and demonstrate that it encodes a conserved wallassociated receptor kinase (WAK)-like protein, which detects the presence of a matching apoplastic effector and confers pathogen resistance without a hypersensitive response. This report demonstrates gene-for-gene disease resistance controlled by this class of proteins in plants. Moreover, Stb6 is, to our knowledge, the first cloned gene specifying resistance to Zymoseptoria tritici, an important foliar fungal pathogen affecting wheat and causing economically damaging septoria tritici blotch (STB) disease

Comment produire un inoculum de Fusarium graminearum en grande quantité pour le criblage de nouvelles sources de résistance à la fusariose de l’épi au champ ?

La fusariose de l’épi ou FHB est une maladie d’origine fongique qui affecte le rendement et la qualité sanitaire des céréales. Elle est causée par un complexe d’espèces, appartenant principalement au genre Fusarium, l’agent principal étant Fusarium graminearum. À ce jour, on ne connait pas de résistance totale à la maladie. Les méthodes de lutte les plus efficaces associent donc variétés partiellement résistantes, traitements antifongiques et pratiques culturales. Ces méthodes s’avèrent toutefois incapables de contrôler la maladie en cas de fortes pressions parasitaires. Il est donc indispensable d’identifier de nouvelles sources de résistance plus efficaces et plus durables en passant par le criblage de collections et panels de variétés. Cela repose sur notre capacité à mettre en place des essais « maladie » de grande ampleur au champ ou en tunnel, et donc de disposer d’inoculum infectieux de Fusarium graminearum en grande quantité. Cet article décrit une méthodologie de production de macroconidies de Fusarium graminearum, permettant d’obtenir de façon régulière et pour différentes souches de F. graminearum, plus de 20 L d’inoculum à une concentration de 105 spores / mL par semaine. Développée à partir d’un protocole utilisé en routine au laboratoire pour de petites productions de spores d’espèces de Fusarium diverses (F. graminearum, F. poae, F. culmorum, F. tricinctum), elle est potentiellement applicable à d’autres espèces

Evaluation d'un nouveau score pronostique, le Score T.A.V.I., chez les patients sélectionnés pour un remplacement valvulaire aortique percutané (Etude préliminaire menée chez 81 patients au C.H.U. de Montpellier)

OBJECTIVES: This study evaluated the T.A.V.I Score as predictor of mortality and major strokes or renal failure requiring dialysis at 6 months (composite criteria). BACKGROUND: There is no risk score suitable for transcatheter aortic valve implantation (TAVI) and designed to select patients at very high risk who might be contraindicated or require geriatric advice. METHODS AND RESULTS: A total of 81 consecutive patients (median age 84 years [79-87]) underwent TAVI between August 2011 and September 2012 in 6 centers. Edwards SAPIEN and Medtronic CoreValve devices were implanted in 66.5% and 39.5% of patients, respectively. Six months follow-up was available for 55,6% of patients. The analysis was performed on 55 patients. In total, 16 patients (29,1%) achieved the composite criteria. Rates of mortality, major strokes and renal failure requiring dialysis were 25,5%, 5,5% and 1,8%, respectively. The T.A.V.I Score was not significantly different in patients who met the composite criteria (7,2 versus 6,7 ; p=0,576). No significant difference was found between the two groups regarding various baseline characteristics, the EuroScore and the STS Score. Peripheral vascular disease (odds ratio [OR] = 3.4) and history of atrial fibrillation (OR=3,4) were associated with a trend level of significance of higher risk of meeting the composite criteria. CONCLUSION: In that preliminary study, the T.A.V.I Score was not predictive of adverse outcomes described by the composite criteria. However, longer follow-up with evaluation of quality of life is required as well as more patients need to be enrolled to increase statistical power.MONTPELLIER-BU Médecine UPM (341722108) / SudocMONTPELLIER-BU Médecine (341722104) / SudocSudocFranceF

Comment produire un inoculum de Fusarium graminearum en grande quantité pour le criblage de nouvelles sources de résistance à la fusariose de l’épi au champ ?

La fusariose de l’épi ou FHB est une maladie d’origine fongique qui affecte le rendement et la qualité sanitaire des céréales. Elle est causée par un complexe d’espèces, appartenant principalement au genre Fusarium, l’agent principal étant Fusarium graminearum. À ce jour, on ne connait pas de résistance totale à la maladie. Les méthodes de lutte les plus efficaces associent donc variétés partiellement résistantes, traitements antifongiques et pratiques culturales. Ces méthodes s’avèrent toutefois incapables de contrôler la maladie en cas de fortes pressions parasitaires. Il est donc indispensable d’identifier de nouvelles sources de résistance plus efficaces et plus durables en passant par le criblage de collections et panels de variétés. Cela repose sur notre capacité à mettre en place des essais « maladie » de grande ampleur au champ ou en tunnel, et donc de disposer d’inoculum infectieux de Fusarium graminearum en grande quantité. Cet article décrit une méthodologie de production de macroconidies de Fusarium graminearum, permettant d’obtenir de façon régulière et pour différentes souches de F. graminearum, plus de 20 L d’inoculum à une concentration de 105 spores / mL par semaine. Développée à partir d’un protocole utilisé en routine au laboratoire pour de petites productions de spores d’espèces de Fusarium diverses (F. graminearum, F. poae, F. culmorum, F. tricinctum), elle est potentiellement applicable à d’autres espèces