Extended Iterative Scheme for QCD: Three-point Vertices

In the framework of a generalized iterative scheme introduced previously to account for the non-analytic coupling dependence associated with the renormalization-group invariant mass scale Lambda, we establish the self-consistency equations of the extended Feynman rules (Lambda-modified vertices of zeroth perturbative order) for the three-gluon vertex, the two ghost vertices, and the two vertices of massless quarks. Calculations are performed to one-loop-order, in Landau gauge, and at the lowest approximation level (r=1) of interest for QCD. We discuss the phenomenon of compensating poles inherent in these equations, by which the formalism automatically cancels unphysical poles on internal lines, and the role of composite-operator information in the form of equation-of-motion condensate conditions. The observed near decoupling of the four-gluon conditions permits a solution to the 2-and-3-point conditions within an effective one-parameter freedom. There exists a parameter range in which one solution has all vertex coefficients real, as required for a physical solution, and a narrower range in which the transverse-gluon and massless-quark propagators both exhibit complex-conjugate pole pairs.Comment: 28 pages, 7 figure

Modélisation moléculaire des lectines et des glycosyltransferases

Les glycosyltransférases et les lectines sont deux familles de protéines impliquées respectivement dans la biosynthèse et la reconnaissance spécifique des glucides. Une partie de ces travaux a été consacrée à la mise à jour de la base de données des structures cristallographiques de glycosyltransférases. La modélisation par homologie de certaines glycosyltransférases d'intérêt biologique dont les structures cristallographiques n'ont pas encore été résolues a été effectuée. Des simulations de dynamique moléculaire de la glycosyltransférase LgtC, qui participe à la biosynthèse des lipooligosaccharides (LOS) chez la bactérie Neisseria meningitidis, ont permis de suggérer un mécanisme de réaction. La lectine PA-IlL de Pseudomonas aeruginosa présente une affinité inhabituellement forte pour le fucose. Les calculs quantiques sur un modèle incluant le site de liaison de la lectine en complexe avec le fucose ont montré que la l'interaction forte entre la protéine et le ligand pourrait partiellement être causée par une délocalisation importante des charges électrostatiques.Glycosyltransferases and lectins are two protein families participating in the biosynthesis and specific recognition of glyacans. One part ofthis work ha been dedicated to the update of database of crystallographic structures of glycosyltransferases. Homology modeling of sorne biologically interesting glycosyltransferases whose crystallographic structures have not been solved yet has been performed. Molecular dynamics simulations ofthe glycosyltransferase LgtC, which participates on the biosynthesis oflipooligosaccharides (LOS) in the bacteria Neisseria meningitidis, allowed us to propose a reaction mechanism. PA-IlL lectin, from Pseudomoans aeruginosa, displays an unusually high affinity for fucose. Quantum chemical calculations on the model including th binding site ofthe lectin in complex with fucose have shown that the strong binding between the protein and the ligand could be partly due to a significant delocalization of electrostatic charges.GRENOBLE1-BU Sciences (384212103) / SudocSudocFranceF

Abstract book of the 26. dvs Hochschultag from 20.-22.09.2023

Czyrnick-Leber U, Kuhrs K, Kraft C, Wicker P, Gröben B. Der Effekt eines tänzerischen Kampfkunsttrainings auf die Konzentrationsfähigkeit von Strafgefangenen. In: Schlesinger T, Grimminger-Seidensticker E, Ferrauti A, et al., eds. Leistung steuern. Gesundheit stärken. Entwicklung fördern. . Bochum; 2023: 44