Search results for "RMN"
showing 10 items of 52 documents
Conformación tridimensional y reconocimiento molecular de biopolímeros : aplicación de RMN multidimensional y desarrollo de metodología de cálculo y …
1998
El objetivo principal de la Tesis ha sido la exploración, el análisis y el perfeccionamiento de las técnicas más habituales utilizadas en la determinación de la estructura y dinámica de biopolímeros en disolución. En concreto, se han utilizado métodos teóricos y experimentales para obtener las estructuras de dos biopolímeros entre los grupos más numerosos de ellos: proteínas y ácidos nucleicos. La obtención de la estructura de una proteína de interés bioquímico por sus peculiaridades cinéticas mediante dos técnicas diferentes ha sido uno de los objetivos principales en la Tesis. La aplicación de las técnicas de modelización por homología y la realización de un análisis exhaustivo sobre los …
Caracterización estructural de Heparanasa por RMN : nuevas estrategias en la búsqueda de fármacos antimetastásicos
2012
Las células tumorales requieren la habilidad de degradar la matriz extracelular para invadir tejidos sanos y convertirse en células metastásicas. Heparanasa es una endo-β-D-glucosidasa capaz de degradar específicamente uno de los componentes de la matriz extracelular, el Heparán Sulfato. Se ha encontrado que la expresión de Heparanasa aumenta en numerosos procesos cancerígenos y que hay una correlación directa entre la producción de Heparanasa y el poder de invasión de las células tumorales. La implicación de Heparanasa en la progresión del cáncer la convierte en una diana muy atractiva para el tratamiento de tumores, enfatizado por el hecho de que parece ser una enzima única, en contraste …
Chemical and biological study of saponins isolated from three malagasy species belonging to Caryophyllaceae, Pittosporaceae and Solanaceae families
2013
This thesis was carried out in the Laboratory of Pharmacognosy, in the Pharmacy section of the University of Burgundy. The principal theme of this laboratory is the research of natural compounds from tropical biodiversity, mainly saponins. In this context, the study of Malagasy plants, Polycarpaea corymbosa Lamk. (CARYOPHYLLACEAE), Pittosporum verticillatum Bojer subsp. verticillatum (PITTOSPORACEAE), Solanum incanum L. and S. heteracanthum Dunal. (SOLANACEAE) led to the isolation of fifteen natural glycosides by column chromatography, medium pressure liquid chromatography, flash chromatography, and vacuum liquid chromatography. The structures were elucidated mainly by the use of spectrosco…
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…
Optimal control of inhomogeneous spin ensembles : applications in NMR and quantum optics
2018
The goal of this thesis is to apply optimal control theory to the dynamics ofinhomogeneous spin ensembles. The first part focuses on the control of a spin ensemble coupled to a cavity. The theory is introduced in detail, and a general method to efficiently control spins ispresented. Several pulses are derived in the bad/good cavity regimes using numerical optimal control techniques. Additionally, non-linear generalized functions are used in order to derivesimple approximated solutions. In a second step, the problem of spin echo Signal to Noise Ratio maximization is investigated, and maximization conditions are derived. It is shown that new pulses are superior to state-of-the-art square puls…
Libération du sodium et des composés d'arôme dans des modèles fromagers aromatisés : influence de la structure et de la composition
2010
Authorities have called for salt content to be reduced in various food products. Cheese appears to be one of the most targeted products. In order to understand how to reduce salt content in model cheeses without modifying salty perception, the interactions between in-mouth sodium release and cheese composition and structure have to be studied. . The current study was conducted to determine how the release of aroma compounds and sodium ions could be modified by the structure and the composition of model cheese (lipid/protein ratio, sodium content ...). This will be done by in vivo and in vitro approaches. 23Na Nuclear Magnetic Resonance (NMR) spectroscopy was used to study the mobility and t…
Tomographies Optiques et NeuroImageries Rhône-alpines chez le petit animal
2009
International audience
Tomographies Optique Diffuse spectrale et spatiale: réponse hémodynamique cérébrale à une stimulation acoustique chez le diamant mandarin
2009
International audience
Interaction between armenian-clay-based ceramics and model wines
2022
The use of ceramics for the transformation or conservation of wine has existed since the origins of wine, but the impact of ceramics on wine has not received much attention.However, in contact with the wine, ceramics are generally not neutral materials and the constituent minerals of ceramics are led to dissolve. This work mainly aims to study the migration of elements from ceramics to wine.To our knowledge, this question has so not been addressed so far, at least with our chosen approach.This study required the prior characterization of the materials and the ceramics produced in the laboratory.The analyzes (XRF, XRD, and SEM/EDX) revealed that the natural material used for the manufacture …
Resonance magnetique nucleaire et chimie structurale
1990
National audience