L’induction : une notion qui brouille les circuits et envoie du bruit sur la ligne

Enseignant la communication dans plusieurs cursus universitaires, je suis toujours étonnée de l’insistance avec laquelle les étudiants répètent le schéma de Shannon comme un point de départ à la compréhension de toute situation de communication. En y regardant de plus près, la chose est fort compréhensible : la plupart des manuels pédagogiques destinés aux étudiants de ces filières présentent ce shéma dès leurs premières pages pour le tempérer ensuite par des apports chronologiquement plus ré..

Essential self-adjointness for combinatorial Schr\"odinger operators II- Metrically non complete graphs

We consider weighted graphs, we equip them with a metric structure given by a weighted distance, and we discuss essential self-adjointness for weighted graph Laplacians and Schr\"odinger operators in the metrically non complete case.Comment: Revisited version: Ognjen Milatovic wrote to us that he had discovered a gap in the proof of theorem 4.2 of our paper. As a consequence we propose to make an additional assumption (regularity property of the graph) to this theorem. A new subsection (4.1) is devoted to the study of this property and some details have been changed in the proof of theorem 4.

Eigenvalues of Laplacian with constant magnetic field on non-compact hyperbolic surfaces with finite area

We consider a magnetic Laplacian $-\Delta_A=(id+A)^\star (id+A)$ on a noncompact hyperbolic surface \mM with finite area. $A$ is a real one-form and the magnetic field $dA$ is constant in each cusp. When the harmonic component of $A$ satifies some quantified condition, the spectrum of $-\Delta_A$ is discrete. In this case we prove that the counting function of the eigenvalues of $-\Delta_{A}$ satisfies the classical Weyl formula, even when $dA=0.

Magnetic bottles on geometrically finite hyperbolic surfaces

We consider a magnetic Laplacian on a geometrically finite hyperbolic surface, when the corresponding magnetic field is infinite at the boundary at infinity. We prove that the counting function of the eigenvalues has a particular asymptotic behaviour when the surface has an infinite area

Penicillin-binding Proteins (PBP) and Lmo0441 (a PBP-like protein) play a role in Beta-lactam sensitivity of Listeria monocytogenes

While seven penicillin-binding proteins (PBPs) or PBP-like proteins have been identified either by radiolabelled penicillin binding studies or genomic analysis, only PBP3 has been considered of interest for Beta-lactams activity against Listeria monocytogenes. Herein we reveal that both PBP4 and Lmo0441 (a PBP-like protein) play a direct role in cephalosporin activity in L. monocytogenes while PBP4 additionally has a protective affect against both penicillin and carbapenem

Draft genome sequences of gammaproteobacterial methanotrophs isolated from marine ecosystems

The genome sequences of Methylobacter marinus A45, Methylobacter sp. strain BBA5.1, and Methylomarinum vadi IT-4 were obtained. These aerobic methanotrophs are typical members of coastal and hydrothermal vent marine ecosystems

The antifungal plant defensin AhPDF1.1b is a beneficial factor involved in adaptive response to zinc overload when it is expressed in yeast cells

Antimicrobial peptides represent an expanding family of peptides involved in innate immunity of many living organisms. They show an amazing diversity in their sequence, structure, and mechanism of action. Among them, plant defensins are renowned for their antifungal activity but various side activities have also been described. Usually, a new biological role is reported along with the discovery of a new defensin and it is thus not clear if this multifunctionality exists at the family level or at the peptide level. We previously showed that the plant defensin AhPDF1.1b exhibits an unexpected role by conferring zinc tolerance to yeast and plant cells. In this paper, we further explored this activity using different yeast genetic backgrounds: especially the zrc1 mutant and an UPRE-GFP reporter yeast strain. We showed that AhPDF1.1b interferes with adaptive cell response in the endoplasmic reticulum to confer cellular zinc tolerance. We thus highlighted that, depending on its cellular localization, AhPDF1.1b exerts quite separate activities: when it is applied exogenously, it is a toxin against fungal and also root cells, but when it is expressed in yeast cells, it is a peptide that modulates the cellular adaptive response to zinc overload

Pour apprendre à apprendre l’informatique, peut-on se contenter d’un MOOC ?

TALN_HCERES2020L'égalité des chances au XXIe siècle passe par une éducation populaire massive aux fondements dunumérique, et pour cela, en France, il faut former plusieurs centaines de milliers de formateurs sur ce sujet,souvent inédit pour elles ou eux. Peut-on simplement supposer que déployer un MOOC va permettre derelever ce défi ? Cet article répond de manière constructive par la négative à cette vision simplifiée, etpropose de déployer un dispositif hybride de formation présentielle et en ligne. Très concrète, cetteproposition correspond au projet Class'Code qui est en train de se déployer, et le travail de recherchepréparatoire ce projet désormais accepté est partagé ici

Draft Genome Sequences of Two Gammaproteobacterial Methanotrophs Isolated from Rice Ecosystems

The genomes of the aerobic methanotrophs “Methyloterricola oryzae” strain 73aT and Methylomagnum ishizawai strain 175 were sequenced. Both strains were isolated from rice plants. Methyloterricola oryzae strain 73aT represents the first isolate of rice paddy cluster I, and strain 175 is the second representative of the recently described genus Methylomagnum