Search results for "molécula"
showing 10 items of 109 documents
Alignement moléculaire sous impulsions laser ultracourtes
2006
Talk given by O. Faucher; National audience
La molécule d'éthylène soumise à des impulsions laser femtosecondes : spectroscopie rotationnelle et alignement
2006
Talk given by B. Lavorel
Alignement moléculaire par impulsions laser ultrabrèves : Mesures & Applications
2009
The interaction of an intense ultrashort laser pulse with a molecular sample leads, after the end of the pulse, to molecular alignment at specific time under field-free conditions. This thesis is dedicated to the measurements and applications of this effect. The degree of alignment is determined through the variation of the refractive index induced by the rearrangement of the molecular dipoles. A two-dimensional technique allowing to measure molecular alignment on a single-shot basis is reported in this document. The alignment is then exploited in order to determine physical quantities which are usually difficult to estimate through others methods. The "cross-defocusing technique" has been …
PLASMONIQUE MOLÉCULAIRE : SPECTROSCOPIE SUR SURFACE MÉTALLIQUE ET MATÉRIAUX HYBRIDES POUR LA PHOTONIQUE INTÉGRÉE
2009
Ce document synthétise mes travaux de recherches sur la période 2002-2009. Les axes majeurs de mon activité portent sur le couplage de molécules avec des particules métalliques, supportant des modes plasmons (SPP) : - Microscopie et spectroscopie optiques en champ proche, - Relaxation moléculaire par couplage aux plasmons, en particulier, la possibilité de modifier les propriétés d'émission de molécules par couplage avec des structures métalliques, – Composants plasmoniques pour la photonique intégrée, où, à l'inverse, l'ingéniérie de matériaux optiques (polymères dop´es, non linéaire, . . .) permet de contrôler la propagation de SPPs le long de films métalliques. Finalement, je démontrerai…
Qauntum control of molecular rotation and of processes in Nuclear Magnetic Resonance
2019
The goal of this thesis is to apply quantum control techniques to manipulate molecular rotation and to enhance the efficiency of processes in Nuclear Magnetic Resonance.These techniques have been used theoretically and experimentally to control the orientation of a symmetric top molecule by means of THz laser fields. This study has been extended to the case of a long interaction distance between the field and the sample. In this case, the molecule cannot be approximated as isolated. We have also shown the extend to which the time evolution of the degree of orientation can be shaped. Optimal control techniques were used to design the THz field which allows to reach the corresponding dynamics…
Scientific studies conducted to understand, improve the soil and increase its yield despite the current unfavorable environmental context.
2022
Contribution of molecular biology techniques to the knowledge of soil microbial diversity and functions
2012
Depuis le développement de l’industrialisation, de l’urbanisation et de l’agriculture intensive, le sol est de plus en plus soumis à de nombreuses variations des conditions environnementales entraînant des modifications de la diversité taxonomique et de la fonctionnalité des communautés microbiennes indigènes. Par conséquent, la question de la signification fonctionnelle de ces pertes/modifications de biodiversité en termes de capacité des écosystèmes à maintenir les fonctions et services dont l’humanité dépend est aujourd’hui centrale. Dans ce contexte, un des challenges en écologie microbienne est de mieux définir et comprendre les processus qui génèrent et maintiennent la diversité micro…
Structure-function analysis of peroxisomal ATP-binding cassette transporters using chimeric dimers
2014
Background: Peroxisomal ABC transporters are predicted to function as homodimers in mammals. [br/] Results: ABCD1 interacts with ABCD2. Chimeric proteins mimicking full-length dimers represent novel tools for functional study. Artificial homodimers and heterodimers are functional. [br/] Conclusion: Interchangeability between ABCD1 and ABCD2 is confirmed, but PUFA transport depends on ABCD2. [br/] Significance: For the first time, heterodimers in mammals are proven to be functional.[br/] ABCD1 and ABCD2 are two closely related ATP-binding cassette half-transporters predicted to homodimerize and form peroxisomal importers for fatty acyl-CoAs. Available evidence has shown that ABCD1 and ABCD2 …
Marquage de molécules biologiques par des complexes de radiométaux à base de polyamines macrocycliques
2012
This work conducted at the “Institut de Chimie Moléculaire de l’Université de Bourgogne” carries at first on the synthesis of bifunctional chelating agents suitable for the chelation of trivalent radiometals, including indium-111. The greater part of this work was then dedicated to the grafting of a DOTA derivative bifunctional chelating agent on different antibodies or fragments of monoclonal antibodies: trastuzumab (anti-HER2 treatment of breast cancer), cetuximab (anti EGFR, treatment of many cancers, including colorectal cancer) and abciximab (antiplatelet). Particular attention was paid to the characterization of various immunoconjugates. The critical step of this thesis consisted in t…
Olfactory neurons plasticity : environment effects during development
2012
In order to investigate the consequences of postnatal odorant exposure on a specific population of olfactory sensory neurons (OSNs), we have taken the following experimental approach. MOR23-GFP mice were daily exposed to Lyral for 21 days starting at birth and three lines of investigations were carried out. Using anatomical analysis we observe that the density of OSNs expressing MOR23 decreases after odorant exposure. This decrease concerns primarily matures OSN (MOR23-OMP+). In order to study molecular changes within individual OSNs, mRNA levels for olfactory signaling pathway components were quantitatively analyzed using qPCR on GFP-labeled neurons (7 per mouse). mRNAs for CNGA2, PDE1C an…