17 research outputs found
DĂ©termination de la diversitĂ© gĂ©nĂ©tique dâune population de Septoria tritici sur blĂ© tendre via une caractĂ©risation culturale et pathogĂ©nique
The study of the genetic diversity of a population of Septoria tritici (Rob. ex Desm.) on bread wheat was carried out by morphologic and pathogenic characterization of isolates secured from the major wheat growing areas in Morocco. Morphologic characterization of 38 isolates showed a very marked difference between theses isolates and between/within regions. Indeed, the fungus presented 2 forms, aspect of yeast and aspect of stromatic pads. Concerning the color, 6 colors were noted: pink, orange, white, green olives, brown and black. We underlined the predominance (77 %) of the pink, orange and white color. Also, the classification of the 26 isolates studied on the basis of percentage of the leaf area necrosed with detached leaves technique gave resulting in three groups (Avirulent- Moderately virulent- Virulent). Moreover, the hierarchical classification of 14 isolates gave place to 9 pathotypes. Our results suggested that there were significant differences within isolates indicating a high genetic diversity of the pathogen in Morocco.LâĂ©tude de la diversitĂ© gĂ©nĂ©tique dâune population de Septoria tritici (Rob. ex Desm.) sur blĂ© tendre a Ă©tĂ© rĂ©alisĂ©e par la caractĂ©risation culturale et pathogĂ©nique dâisolats collectĂ©s dans diffĂ©rentes rĂ©gions cĂ©rĂ©aliĂšres du Maroc. La caractĂ©risation culturale de 38 isolats in vitro a montrĂ© une diffĂ©rence trĂšs marquĂ©e entre les isolats Ă©tudiĂ©s et entre/intra rĂ©gions. En effet, le champignon a prĂ©sentĂ© 2 formes, lâaspect de levure et lâaspect de bourrelets stromatiques. Concernant la couleur: 6 couleurs ont Ă©tĂ© notĂ©es. Elle varie entre rose, orange, blanche, vert olivĂątre, marron, et noir. On a notĂ© la dominance de la couleur rose, orange et blanche avec 77% du total des cultures. Aussi, la classification des 26 isolats Ă©tudiĂ©s sur la base du pourcentage de la surface foliaire nĂ©crosĂ©e moyennant la technique des feuilles dĂ©tachĂ©es a donnĂ© lieu Ă trois groupes (Avirulent- Moyennement virulent- Virulent). De plus, la classification hiĂ©rarchique de 14 isolats a donnĂ© lieu Ă 9 pathotypes. Cette diffĂ©rence nette entre les isolats montre quâil yâa une grande diversitĂ© au sein de cette population
Long-Term Implications of Atrial Fibrillation in Patients With Degenerative Mitral Regurgitation
Background: Scientific guidelines consider atrial fibrillation (AF) complicating degenerative mitral regurgitation (DMR) a debated indication for surgery. Objectives: This study analyzed the prognostic/therapeutic implications of AF at DMR diagnosis and long-term. Methods: Patients were enrolled in the MIDA (Mitral Regurgitation International Database) registry, which reported the consecutive, multicenter, international experience with DMR due to flail leaflets echocardiographically diagnosed. Results: Among 2,425 patients (age 67 \ub1 13 years; 71% male, 67% asymptomatic, ejection fraction 64 \ub1 10%), 1,646 presented at diagnosis with sinus rhythm (SR), 317 with paroxysmal AD, and 462 with persistent AF. Underlying clinical/instrumental characteristics progressively worsened from SR to paroxysmal to persistent AF. During follow-up, paroxysmal and persistent AF were associated with excess mortality (10-year survival in SR and in paroxysmal and persistent AF was 74 \ub1 1%, 59 \ub1 3%, and 46 \ub1 2%, respectively; p < 0.0001), that persisted 20 years post-diagnosis and independently of all baseline characteristics (p values <0.0001). Surgery (n = 1,889, repair 88%) was associated with better survival versus medical management, regardless of all baseline characteristics and rhythm (adjusted hazard ratio: 0.26; 95% confidence interval: 0.23 to 0.30; p < 0.0001) but post-surgical outcome remained affected by AF (10-year post-surgical survival in SR and in paroxysmal and persistent AF was 82 \ub1 1%, 70 \ub1 4%, and 57 \ub1 3%, respectively; p < 0.0001). Conclusions: AF is a frequent occurrence at DMR diagnosis. Although AF is associated with older age and more severe presentation of DMR, it is independently associated with excess mortality long-term after diagnosis. Surgery is followed by improved survival in each cardiac rhythm subset, but persistence of excess risk is observed for each type of AF. Our study indicates that detection of AF, even paroxysmal, should trigger prompt consideration for surgery
Modern concept of acoustic emission (AE) coupled with electrochemical measurements for monitoring the elastomer-coated carbon steel damage in phosphoric acid medium
International audienc
ErosionâCorrosion Effect on the Alloy 316L in Polluted Phosphoric Acid
cited By 0International audienceThe physical factors such as the abrasive particles (AP) cause a mechanical rupture of the passive film in the polluted phosphoric acid. In this sense, the electrochemical methods and mass loss measurement were used to study the effect of these abrasive particles. X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy analysis (SEM/EDX) and UVâVisâNIR spectroscopy methods were employed to analyze the material surface. The experimental results of X-ray diffraction showed that the AP affect the formation of passive film by decreasing the intensity of ferritic phases after 6 h of immersion. The measurements of polarization reveal that the erosionâcorrosion accentuates the anodic dissolution of the material, which is manifested by an increase of the activation and passivity of current densities. The EIS exhibited a decrease in the polarization resistance of material caused by the reduction of the film thickness. The interpretation of the UVâVisâNIR spectroscopy showed that the mechanical effect diminishes the passive film formation. In addition, the passive current density increases under the abrasionâcorrosion condition which was approved by MottâSchottky analysis. It is manifested by the formation of a porous outer layer and decrease in the properties of the inner layer, which was observed by UVâVisâNIR and MottâSchottky analysis, respectively. © 2019, Springer Nature Switzerland AG
Long-Term Implications of Atrial Fibrillation in Patients With Degenerative Mitral Regurgitation
Background: Scientific guidelines consider atrial fibrillation (AF) complicating degenerative mitral regurgitation (DMR) a debated indication for surgery. Objectives: This study analyzed the prognostic/therapeutic implications of AF at DMR diagnosis and long-term. Methods: Patients were enrolled in the MIDA (Mitral Regurgitation International Database) registry, which reported the consecutive, multicenter, international experience with DMR due to flail leaflets echocardiographically diagnosed. Results: Among 2,425 patients (age 67 ± 13 years; 71% male, 67% asymptomatic, ejection fraction 64 ± 10%), 1,646 presented at diagnosis with sinus rhythm (SR), 317 with paroxysmal AD, and 462 with persistent AF. Underlying clinical/instrumental characteristics progressively worsened from SR to paroxysmal to persistent AF. During follow-up, paroxysmal and persistent AF were associated with excess mortality (10-year survival in SR and in paroxysmal and persistent AF was 74 ± 1%, 59 ± 3%, and 46 ± 2%, respectively; p < 0.0001), that persisted 20 years post-diagnosis and independently of all baseline characteristics (p values <0.0001). Surgery (n = 1,889, repair 88%) was associated with better survival versus medical management, regardless of all baseline characteristics and rhythm (adjusted hazard ratio: 0.26; 95% confidence interval: 0.23 to 0.30; p < 0.0001) but post-surgical outcome remained affected by AF (10-year post-surgical survival in SR and in paroxysmal and persistent AF was 82 ± 1%, 70 ± 4%, and 57 ± 3%, respectively; p < 0.0001). Conclusions: AF is a frequent occurrence at DMR diagnosis. Although AF is associated with older age and more severe presentation of DMR, it is independently associated with excess mortality long-term after diagnosis. Surgery is followed by improved survival in each cardiac rhythm subset, but persistence of excess risk is observed for each type of AF. Our study indicates that detection of AF, even paroxysmal, should trigger prompt consideration for surgery