Une solution analytique verte pour le PAT: la spectroscopie proche infrarouge.

Conference (2011, May 19)

Solution Nuclear Magnetic Resonance Structure and Molecular Dynamics Simulations of a Murine 18.5 kDa Myelin Basic Protein Segment (S72-S107) in Association with Dodecylphosphocholine Micelles.

in Biochemistry (2012), 51(38), 7475-87

The 18.5 kDa myelin basic protein (MBP), the most abundant splice isoform in adult mammalian myelin, is a multifunctional, intrinsically disordered protein involved in the development and compaction of ... [more ▼]

The 18.5 kDa myelin basic protein (MBP), the most abundant splice isoform in adult mammalian myelin, is a multifunctional, intrinsically disordered protein involved in the development and compaction of the myelin sheath in the central nervous system. A highly conserved central segment comprises a membrane-anchoring amphipathic alpha-helix followed by a proline-rich segment that represents a ligand for SH3 domain-containing proteins. Here, we have determined using solution nuclear magnetic resonance spectroscopy the structure of a 36-residue peptide fragment of MBP (murine 18.5 kDa residues S72-S107, denoted the alpha2-peptide) comprising these two structural motifs, in association with dodecylphosphocholine (DPC) micelles. The structure was calculated using CS-ROSETTA (version 1.01) because the nuclear Overhauser effect restraints were insufficient for this protein. The experimental studies were complemented by molecular dynamics simulations of a corresponding 24-residue peptide fragment (murine 18.5 kDa residues E80-G103, denoted the MD-peptide), also in association with a DPC micelle in silico. The experimental and theoretical results agreed well with one another, despite the independence of the starting structures and analyses, both showing membrane association via the amphipathic alpha-helix, and a sharp bend in the vicinity of the Pro93 residue (murine 18.5 kDa sequence numbering). Overall, the conformations elucidated here show how the SH3 ligand is presented to the cytoplasm for interaction with SH3 domain-containing proteins such as Fyn and contribute to our understanding of myelin architecture at the molecular level. [less ▲]

Une solution numérique au test de Cattell pour déterminer le nombre de composantes principales à retenir

Conference (2009, May)

Solution of topology optimization problems with sequential convex programming

Speech (2003)

Introduction to efficient solution algorithms to large scale topology optimization problems.

Solution structural study of BlaI: Implications for the repression of genes involved in beta-lactam antibiotic resistance

in Journal of Molecular Biology (2003), 333(4), 711-720

Solution structure of human prolactin

in Journal of Molecular Biology (2005), 351(4), 810-23

We report the solution structure of human prolactin determined by NMR spectroscopy. Our result is a significant improvement over a previous structure in terms of number and distribution of distance ... [more ▼]

We report the solution structure of human prolactin determined by NMR spectroscopy. Our result is a significant improvement over a previous structure in terms of number and distribution of distance restraints, regularity of secondary structure, and potential energy. More significantly, the structure is sufficiently different that it leads to different conclusions regarding the mechanism of receptor activation and initiation of signal transduction. Here, we compare the structure of unbound prolactin to structures of both the homologue ovine placental lactogen and growth hormone. The structures of unbound and receptor bound prolactin/placental lactogen are similar and no noteworthy structural changes occur upon receptor binding. The observation of enhanced binding at the second receptor site when the first site is occupied has been widely interpreted to indicate conformational change induced by binding the first receptor. However, our results indicate that this enhanced binding at the second site could be due to receptor-receptor interactions or some other free energy sources rather than conformational change in the hormone. Titration of human prolactin with the extracellular domain of the human prolactin receptor was followed by NMR, gel filtration and electrophoresis. Both binary and ternary hormone-receptor complexes are clearly detectable by gel filtration and electrophoresis. The binary complex is not observable by NMR, possibly due to a dynamic equilibrium in intermediate exchange within the complex. The ternary complex of one hormone molecule bound to two receptor molecules is on the contrary readily detectable by NMR. This is in stark contrast to the widely held view that the ternary prolactin-receptor complex is only transiently formed. Thus, our results lead to improved understanding of the prolactin-prolactin receptor interaction. [less ▲]

Solutions face au départ précoce des travailleurs : étude de cas

in Psychologie du Travail et des Organisations (2007), 13(2), 5-22

The aim of the present study is to identify actions to prevent early job retirement among employees and executives belonging to a company specialized in medical products. After a diagnosis stage (stress ... [more ▼]

The aim of the present study is to identify actions to prevent early job retirement among employees and executives belonging to a company specialized in medical products. After a diagnosis stage (stress measure, assessment of the intent to leave and identification of the relevant leaving factors), twenty workers were interviewed. A content analysis underlines that actions in the field of communication like informational support during organizational changes and the establishment of an opened relational atmosphere would allow to keep longer workers in activity. The workers are ready for individual learning. The internal mobility is another solution often proposed by the workers. An exploratory questionnaire filled in at the end of the interview allowed us to measure the opinion of the workers about the various solutions suggested in the literature. [less ▲]

Solutions imaginées par les enseignants en éducation physique du secondaire pour lutter contre le phénomène de la dispense dans le cours de natation

in e Journal de la Recherche sur l'Intervention en Éducation Physique et Sport (2007), 11

En Communauté française de Belgique, les professeurs d’éducation physique de l’enseignement secondaire sont actuellement confrontés à une augmentation du nombre d’élèves cherchant à ne pas participer à ... [more ▼]

En Communauté française de Belgique, les professeurs d’éducation physique de l’enseignement secondaire sont actuellement confrontés à une augmentation du nombre d’élèves cherchant à ne pas participer à leurs cours. Ce phénomène atteint des proportions particulièrement préoccupantes dans les cours de natation, avec les classes de filles. Cette étude s’intéresse aux pistes d’actions expérimentées par 50 enseignantes qui ont été interviewées par téléphone. Les réponses ont été classées inductivement dans un système de catégories avec un taux de 97,2% d’accords intra-analystes. Trois types de solutions ont été identifiées : (1) celles qui ont donné des résultats positifs ; (2) celles qui se sont montrées inefficaces et (3) celles que les sujets souhaiteraient tester. Parmi les premières (n = 46), les actions les plus fréquentes se répartissent entre une catégorie coercitive (« menaces/sanctions ») et une catégorie constructive (« Contenu des séances »). Plusieurs autres pistes originales sont discutées. Les solutions s’étant montrées inefficaces s’avèrent étonnamment similaires aux précédentes, mettant en exergue l’extrême variabilité des effets des stimuli pédagogiques. Enfin, il est encourageant de constater que certains enseignants se mobilisent afin de résoudre les problèmes rencontrés sur le terrain. Deux exemples de solutions à expérimenter ont ainsi été identifiés et discutés. [less ▲]

Solutions TP10 - Contact hertzien

Learning material (2010)

Ce chapitre est composé par les solutions des problèmes proposés. Il s'agit des exercices sur le contact hertzien entre deux pièces.

Solutions TP2 Ajustements

Learning material (2010)

Ce document offre les solutions pour les exercices sur les ajustements. On trouve aussi des figure qui simplifient la compréhension des termes spécifiques pour ce chapitre.