Dissertations / Theses on the topic 'Machines et moteurs moléculaires'
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Daou, Dania. "Intégration de moteurs moléculaires photoactivables dans des gels supramoléculaires." Electronic Thesis or Diss., Strasbourg, 2024. http://www.theses.fr/2024STRAF021.
Full textThis thesis explored the integration of light-driven synthetic molecular motors in supramolecular gel networks. The main goal was to achieve reversible macroscopic motion by exploiting both the unidirectional rotation of molecular motors and the reversible nature of supramolecular interactions. Highly functionalized molecular motors have been synthesized and integrated as crosslinking units in supramolecular gel networks of diphenylalanine and poly(γ- benzyl-L-glutamate) peptides, as well as DNA oligonucleotides. Activation of the unidirectional rotation of molecular motors by light, allowed the production of nanomechanical work which is sufficient to disrupt supramolecular interactions in peptide-based gel networks leading to contraction or melting of the gel material at the macroscopic scale. Thanks to the reversible supramolecular interactions, the initial gel material was recovered in the dark, either spontaneously or by applying a thermal stimulus. The systems studied in this thesis represent a novel class of materials operating in dissipative out-of-equilibrium conditions, holding promise of applications in various fields such as biology, medicine and material science
Lemouchi, Cyprien. "Moteurs Moléculaires Cristallins Photo-pilotés." Phd thesis, Université d'Angers, 2010. http://tel.archives-ouvertes.fr/tel-00801226.
Full textRajonson, Gabriel. "Etude et comparaison de moteurs moléculaires artificiels par simulation numérique." Thesis, Angers, 2019. http://www.theses.fr/2019ANGE0029.
Full textThe nanometric field raises a lot of questions. One of them concerns molecular motors. Is it possible to design a device capable of moving itself inside an environment ? If so how can we characterise its motion ? Does it influence the environment ? Does the environment influence the motor’s motion ? We took an interest here to the study of several parameters such as the ratio of the motor’s relative length to the environment’s molecule length, the ratio of the motor’s relative mass to the environment’s molecule mass, the motor’s folding frequency, thetemperature’s influence, the motor’s orientation, the different time configurations. We showed that the motor’s relative length ratio to the environment’s molecule length, as well as the motor’s relative mass ratio to the environment’s molecule mass, have an influence on the motor’s displacement. Every motor presenting one hinge, is subject to the scallop theorem introduced by E.M. Purcell. We found a way to break this theorem by playing on the motor’s folding frequency. Then we altered our motor in order for it to possess to hinges. We studied the effect of different time configuration on the motor’s displacement. Finally we wanted to give a privileged direction to our motor by submitting it to an electrical field
Kott, Esther. "Physiopathologie des dyskinésies ciliaires primitives : approches moléculaires et cellulaires." Paris 6, 2013. http://www.theses.fr/2013PA066360.
Full textCilia are evolutionary conserved and ultra-specialized cell differentiations. Primary ciliary dyskinesia (PCD) are rare autosomal recessive respiratory disorders, due to abnormalities of motile cilia. PCD are associated in ~50% of the cases with situs inversus. A detailed update is made on the components (microtubule doublets, dynein arms, radial spokes, central complex) of the cytoskeleton (the 9 +2 axoneme) of the motile cilia. To date, mutations of 24 genes explain the disease in half of the patients with PCD from the National Center for Rare Respiratory Diseases cohort (313 independent families), on which the work was focused. The goal was to progress in the molecular etiology of PCD. The approaches, combining candidate-genes approach, homozygosity mapping and whole exome sequencing in six independent families, allowed us to involve three new genes: (i) in PCD without dynein arms, LRRC6, which plays a role in the pre-assembly of these structures; (ii) in PCD associated with central complex abnormalities, RSPH1 and HYDIN, which encode a protein of the radial spoke head and a protein of the axoneme central sheath, respectively. The identification of new PCD genes allows the establishment of a definitive diagnosis of PCD, improves genetic counseling and therapeutic care, and also enables a better understanding of the mechanisms involved in the proper building and function of motile cilia in humans
Lang, Thomas. "Synthèse et caractérisation de machines moléculaires à base de porphyrines." Strasbourg, 2010. http://www.theses.fr/2010STRA6201.
Full textThe development of molecular machines is a topic of current interest. The main challenge in this area is to impose the directionality of the movement. Also, the aim of this thesis is the development of new porphyrins based rotary molecular machines bearing at their periphery different recognition sites. In a first part, we describe the synthesis and the study, mainly by NMR spectroscopy, of several tin (IV) handle-porphyrin based molecular turnstiles. The “opened” and “closed” states are characterized and different studies dealing with the “opening-closing” process and the switch between one station to another are performed and discussed. In the second part, we introduce a new type of motor based on bridged-porphyrin. In this case, the rotor is directly attached through a covalent bond to the porphyrin backbone. This type of architectures is developed in order to avoid the collapse of the system due to the low stability of the Sn-O bond in acidic media. Different bridged porphyrins were synthesized and, as for the molecular turnstiles, different “opened” and “closed” states could be reached and characterized
Piecourt, Éric. "Caractérisation électromécanique et alimentation électronique des moteurs piézo-électriques." Toulouse, INPT, 1995. http://www.theses.fr/1995INPT102H.
Full textCharrin, Bénédicte. "La huntingtine et les moteurs moléculaires : fonctions dans le trafic intracellulaire et la mitose." Paris 11, 2006. http://www.theses.fr/2006PA11T020.
Full textLoubery, Sylvain. "Moteurs moléculaires et rôle de l'actine dans le transport intracellulaire des compartiments d'endocytose." Paris 6, 2007. http://www.theses.fr/2007PA066240.
Full textLacroix, Benjamin. "Rôle de la polyglutamylation dans le contrôle sélectif des moteurs moléculaires et des MAPs." Montpellier 2, 2009. http://www.theses.fr/2009MON20196.
Full textMicrotubules (MTs) are cytoskeletal filaments that are essential for many different cellular functions including cell division, intracellular transport and cell motility. Polyglutamylation is a post-translational modification that targets alpha- and beta-tubulin, the building blocks of MTs. This modification is present on the C-terminal tail of the tubulins, which is a main domain of interaction between MTs and MAPs (MTs associated proteins). Tubulin polyglutamylation is a complex modification that can generate long side chains of glutamates on a single modified residue of the protein. My first focus was to characterize the enzymatic properties of the polyglutamylases of the family of TTLLs (Tubulin Tyrosine Ligase Like proteins). I found that each enzyme has a specificity toward initiation or elongation of the side chains and for preferentially modifying alpha or beta tubulin. The polyglutamylation level on MTs varies during the cell cycle: interphase MTs are almost not glutamylated whereas spindle and midbody MTs are strongly modified. This suggests that tubulin polyglutamylation plays a specific role during mitosis. I demonstrated that the glutamylation pattern present on mitotic MTs regulates the localisation and activity of MAPs. I found that the mitotic MAP (TPX2) is recruited specifically to glutamylated MTs and that polyglutamylated tubulin activates the MT-severing activity of two proteins, katanin and spastin
Brisset, Stéphane. "Outil et méthodologie pour la conception des moteurs à réluctance variable à double saillance." Lille 1, 1995. http://www.theses.fr/1995LIL10012.
Full textMartin, Jean-Philippe. "Contribution à l'alimentation en tension de machines synchrones à aimants permanents à nombre de phases élevé : fonctionnement normal et degradé." Vandoeuvre-les-Nancy, INPL, 2003. http://www.theses.fr/2003INPL043N.
Full textThis work deals with the segmented power supply of multi-phase synchronous permanent magnet machines by modular voltage inverters. The supply segmentation obtained by the increase of the windings number allows operating in fault mode, when phases are disconnected from the supply. However, for a voltage supply, the magnetic coupling between windings can lead with the increase of current ripples to generate additional lasses. The q-phase MSAP with unspecified emf waveform is modeled and the optimal current waveform canceling the low frequency torque undulations in normal mode is defined. The generalized Concordia transformation allows to represent a q-phase machine by several mono and 2-phase machines magnetically uncoupled. A simultaneous control method of the q single-phase inverters, based on the use of adapted voltage vectors, allows to minimize the current undulation rate and thus the lasses in the system. When faults occur, leading to the disconnection of phases from the supply, torque undulations of law frequency appear. Several methods, based on the current waveform modification of one or more than one active phases are proposed in the case either of supply by q single-phase inverters or by a qphase inverter. Several methods of filtering are validated by experimental results. Ln order to allow high dynamics current tracking, a new AC current control method with constant switching frequency is presented and study in the final chapter. Based on the used of a hybrid regulator, it associates the robustness of sliding mode controllers and high dynamics of peak current regulators
Smyczynski, Cybelle. "Transduction mécanochimique par les moteurs moléculaires : exemple des complexes actine-myosine et microtubule-kinésine." Montpellier 2, 1999. http://www.theses.fr/1999MON20121.
Full textColard-Itté, Jean-Rémy. "Synthèses et études physico-chimiques de matériaux à base de moteurs moléculaires rotatifs photoactivables." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF044.
Full textThis manuscript describes the gram-scale synthesis of a light-driven rotary molecular motor. It is shown that the target molecule can be integrated into a PEG chains network, and that the UV irradiation of the obtained material leads to its macroscopic contraction. These collective molecular movements are then able to convert light energy to produce a mechanical work of eight orders of magnitude beyond their scale. A combination of rheology and small angle neutron scattering studies defined the of gel formation parameters to obtain maximum contraction, but also the experimental observation that motor rotation initiates PEG chain windings, which is responsible of the contraction of the material.In addition, the synthesis of a modulator unit and its integration into these materials is described. The resulting gels present reversible contraction properties and the out-of-equilibrium behavior of the entire system is then discussed
Vasile, Iulian. "Etude théorique et expérimentale d'un moteur hybride thermo-pneumatique." Orléans, 2005. http://www.theses.fr/2005ORLE2031.
Full textBazine, Sadok. "Conception et implémentation d'un méta-modèle de machines asynchrones en défaut." Poitiers, 2009. http://theses.edel.univ-poitiers.fr/theses/2009/Bazine-Sadok/2009-Bazine-Sadok-These.pdf.
Full textTo carry out research on electrical or mechanical induction machine faults diagnosis, the simulation tool is essential to investigate them. Although in practice some shortcomings are almost impossible to achieve, it is often difficult to reproduce them in simulation without devoting a very important development time. That is why in this thesis, with the idea of using software engineering tools, we had set our goal to automate the generation of induction machine simulators with the presence of various stator and rotor defects. After a survey of different induction machines simulation approaches, we have developed our model with the Electrical Circuits Magnetically Coupled(CEMC) method. First, we have detailed the standalone Meta Model steps to generate a healthy induction machine model, beginning with the basic parts of the model and detailing assembling steps to get the whole induction machine model. This approach is based on stator's, rotor's and stator rotor mutuals, and connection matrices auto-construction according to winding's topology and geometry. After that, we enriched this Meta Model by implementing turns short-circuit in the same phase, short circuit between phase and ground or rotor bar's break. We have shown how this standalone generator takes into account each of witch topological changes by auto extending parameters and connections matrices. This auto-generation methodology was validated with experimental results from faulty induction machine prototypes, and we can say that this simulation plate-form (the Meta Model Object oriented implementation) can be used as a virtual experimentation environment to test techniques of failures detection and location
Locment, Fabrice Piriou Francis Semail Éric. "Conception et modélisation d'une machine synchrone à 7 phases à aimants permanents et flux axial commande vectorielle en modes normal et dégradé /." Villeneuve d'Ascq : Université des sciences et technologies de Lille, 2007. https://iris.univ-lille1.fr/dspace/handle/1908/1033.
Full textBerenger, Christine. "Contribution à l'étude d'une machine synchrone autopilotée à aimants permanents et à enroulements dans l'entrefer." Vandoeuvre-les-Nancy, INPL, 1989. http://www.theses.fr/1989NAN10384.
Full textLebaroud, Abdesselam. "Diagnostic des défauts des machines asynchrones : approche signal et système." Lyon 1, 2007. http://www.theses.fr/2007LYO10288.
Full textThe main piece of the electrical training systems is the induction machine which, during the last three decades, made the object of numerous researches orientated mainly toward the conception of order laws always more competitive. Its numerous qualities, its weak cost, its robustness and its performances make a machine particularly appreciated in industrial middle. The imperatives of reliability and productivity of installations require the incorporation of a system of detection and diagnosis of faults. It is therefore necessary to endow the induction machines of monitoring tools; so we shall be able to avoid faults and untimely stopping. In our step for the faults diagnosis of the induction machine, two approaches have been developed: the first one consists in implementing techniques and methods of treatment and analysis of the signal making facilitating the visual interpretation of the faults and possibly its implantation in a monitoring system. The second approach is said "system" based on tools of classification, in this case Time - frequency Representation (TFR) linked to a decision criterion based on the distances Mahalanobis. The TFR serves to the extraction of the appropriate points which separate maximally, according to the Fisher criteria, two states: one healthy and the other in fault. Nevertheless the choice of points is appraised, what makes this method semi automatic. The association TFR - HMM (Hidden Model of Markov) allows the complete automation of the diagnosis procedure of the faults since the acquisition and the data processing until the decision making
Balog, Mirela. "Synthèse et analyse structurale de nouveaux coronands, cyclophanes et composés 1,3-dioxaniques." Rouen, 2004. http://www.theses.fr/2004ROUES004.
Full textThe stereochemistry investigations performed with 1,3-dioxane derivatives obtained from meso-2,4-pentanediol, 2,6-diacetylpyridine and 5-aryl-2-furaldehydes, shown in the first part of this work, revealed the axial or equatorial preference for several substituents at position 2 of the 1,3-dioxane ring. The atropisomery of some derivatives exhibiting aromatic substituents and the unexpected mass-spectrometry discrimination of cis and trans isomers of some 2,4,6-substituted-1,3-dioxanes were discussed. In the second part of this work we report the synthesis and the structural analysis of a series of coronands with spirane units and cyclophanes which embed in their structure 1,3-dioxane rings. The design of these macrocycle compounds is based on the stereochemistry of the precursors which show a favourable pre-organization for the incorporation in macrocycle systems. The structural analysis is based on high-field NMR investigations (ROESY, NOESY and dynamic experiments), X-ray diffractometry (six molecular structures) and mass spectrometry experiments (MALDI, ESI-MS). These investigations correlate the size of the cavities of different macrocycles with the selectivity of the coordination for different alkali cations and reveal the supramolecular aggregates formed by some of the macrocycle compounds with molecules of solvent and the intra and intermolecular interactions (p-stacking) among the aromatic rings. The tandem flipping of the two 1,3-dioxane rings of the para-para cyclophane, suggesting the dynamics of a rocking chair, was observed as the first example showing the concerted flipping of two six-membered rings incorporated in the same macrocycle
Stefak, Roman. "Synthèse de machines moléculaires pour le contrôle de mouvements de rotation et de translation." Toulouse 3, 2013. http://thesesups.ups-tlse.fr/2124/.
Full textThis thesis contributes to the field of nanosciences. This manuscript reports the work achieved in order to better understand the rotational and translational motions observed in molecules while those are manipulated as single molecular machines. We first studied the dissymmetrization of the stator (lower anchoring part of the motor) by means of two biphenylene moieties. These fragments were selected to reproduce the behavior of sexiphenyls that can easily move on a surface with the motion analogue to a crawling. Therefore, biphenylenes were designed to allow the molecule to drift in a linear way on the surface using the excitation from the STM tip. In this synthesis, we succeeded to obtain the bipodal bearing two biphenylene moieties. The third indazole subunit could not be added to form the desired dissymmetric stator. Starting from the initial design of the molecular motor previously developed in the group, the first goal of this work was to dissymmetrize the rotor (upper rotating part of the motor) by introducing a nitrogen tag with the purpose of being able to visualize the rotation while this latter is induced by the tip of the STM. The obtained rotor bearing five arms will be used as gears to study the transfer of rotation from one to his neighbours. The last part of this work consists in the development of a new family of rotors based on the double-decker architecture. The upper rotating part is a porphyrin ligand displaying electron donating and withdrawing moieties resulting in a strong dipolar moment with an estimated value of 8 Debye. This unique asset can be used in order to control their rotation by applying an STM tip-induced electric field. This rotor is supported on an europium naphthalocyanine fragment which disables the strong interaction between the rotor and the surface. Thus, an europium heteroleptic double-decker was synthesized and fully characterised. Double-deckers have been studied as monolayers on Cu(111) at 80 K and as single molecule on Au(111) at 5 K using an ultra high vacuum STM. Switching as well as free and synchonised rotational behaviors have been evidenced using different values of bias voltage
Durola, Fabien. "Autour de nouveaux chélates:les 8,8'-diphényle-3,3'-biisoquinolines : Machines moléculaires rapides et nouvelles topologies." Strasbourg 1, 2007. http://www.theses.fr/2007STR13189.
Full textKirouac, Mathieu. "Développement de modèles analytiques thermiques pour des machines à aimants permanents." Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26232.
Full textCe mémoire porte sur le développement d’une modélisation thermique avec des modèles analytiques, pour la conception de machines électriques. Il concerne plus particulièrement les structures de machines cylindriques à aimants permanents. Nous discutons ensuite du modèle thermique complet de type circuit thermique qui a été réalisé et confronté à des résultats expérimentaux. Ce modèle a une très bonne précision et il nous a permis d’étudier l’effet de différentes variations topologiques sur le comportement thermique ainsi que différentes stratégies de refroidissement. Ce modèle peut facilement être intégré dans un processus d’optimisation. En nous basant sur les mêmes principes, nous avons proposé un nouveau modèle à résistances thermiques combinées pour modéliser les échanges thermiques entre les conducteurs dans les encoches. Ce modèle permet d’apprécier le caractère aléatoire de la disposition des conducteurs dans la bobine et peut être jumelé à un modèle plus global.
This thesis focuses on the development of a thermal modeling with analytical models for the design of electrical machines. It concerns more particularly cylindrical machine with permanent magnets. The methods used to determine the critical parameters of thermal modeling are presented first. We then present the complete thermal model that has been developed and confronted with experimental results. This model has very good accuracy and has allowed us to study the effect of different topological variations on the thermal behavior. It was also possible to analyze and compare different cooling strategies. This model can easily be integrated into an optimization process to determine the maximum permissible losses of a given configuration, or to define the cooling method to use. Based on the same principles, we proposed a new model to simulate the thermal exchanges between the conductors in the slots. This model allows us to appreciate the randomness of the arrangement of the conductors in the coil. It can be paired with a more comprehensive model of the machine in order to refine the resolution of the latter and ensure a more accurate analysis of the thermal behavior of the coils.
Lateb, Ramdane Meibody-Tabar Farid. "Modélisation des machines asynchones et synchrones à aimants avec prise en compte des harmoniques d'espace et de temps application à la propulsion marine par POD /." S. l. : S. n, 2006. http://www.scd.inpl-nancy.fr/theses/2006_LATEB_R.pdf.
Full textPradalier, Sylvain. "Une approche formelle à la modélisation, simulation et analyse de nano-machines." Palaiseau, Ecole polytechnique, 2009. http://www.theses.fr/2009EPXX0036.
Full textLi, Quan. "Integrated motions of light driven molecular motors at macroscopic scale." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF001/document.
Full textNatural molecular motors such as ATP synthase, myosin, kinesin and dynein can convert conformationalchanges, due to chemical energy input, into directed motion for catalysis and transport. Preparing artificial molecular motors and making them work at different scales (from nano to macroscopic scale) have been long-term challenges. Herein we designed and synthesized a light driven rotary molecular motor in highly enantiopure form and in gram scale. This motor is featured by two orthogonal functionalities on its upper and lower part, allowing its further integration into polymeric materials. By performing click reaction under different concentration conditions, either an eight shaped motor-polymer conjugate or a gel containing motors as reticulation units could be obtained. Upon UV irradiation, the polymer chains could be entangled due to the rotation of this motor. For eight shaped polymer, the dimension was changed towards smaller dimension, and the morphology was changed from cycle to collapsed coils (spherical or more elongated). For the gel, due to the twisting of polymer chains induced by the rotation of the motor, it could be contracted significantly (80 %) compared with its original volume. The integration of machines which display motions out of equilibrium at nanoscale to movement in the macroscopic world which is extensively used in natural systems will open very interesting prospects in nanotechnology for further developments
Missoum, Rachid. "Modélisation, conception et optimisation d'un moteur-générateur pour coupleur électromagnétique." Nantes, 2008. http://www.theses.fr/2008NANT2134.
Full textThis work focuses on the Modelling and the design optimization of an electrical motor-generator integrated in an electromagnetic coupler for automotive applications. A study of electric motor-generators and electromagnetic couplers used mainly in traction systems proposed in literature is presented. For the application witch is the aim of "Defontaine" company we proposed and studied two systems operating on the basis of two different principles. The first system adopts the principle of transmitting torque by friction and uses an axial flux homopolar motor-generator. The second is based on a system of dog clutch ; the motor-generator in this case is a permanents magnets synchronous machine. Both of the two topologies, axial and radial machines are studied. With the aim of design and optimization of the three machines, electromagnetic and thermal models are presented. These models are then coupled with a stochastic particle swarm optimization algorithm. For the particular case of the radial permanent magnet machine, we have developed an original method of optimization based on the direct calculation of the optimal parameters. This method is then used to study the case of the high speed machines. A test bench has been especially designed to validate the developed models and the two principles of electromagnetic couplers
Bekka, Nassim. "Modélisation et optimisation d'actionneurs rotatifs fort couple pour systèmes embarqués." Nantes, 2015. https://archive.bu.univ-nantes.fr/pollux/show/show?id=b0badb6d-3747-42eb-bcf7-0e81b1bc02de.
Full textPermanent magnet machines with fractional slot concentrated windings are very suited in low speed high torque applications, thanks to their high torque density and low manufacturing costs. However, they are characterized by low fundamental winding factor and high content of magnetomotive force (MMF) space harmonics that can lead to undesirable effects, such as eddy current losses in the magnets, acoustic noise and vibration. To overcome these drawbacks, two novel methodologies for optimal design of fractional slot with concentrated windings have been proposed, passive and active methods. The passive method acts on the winding parameters (coil span, number of turns, slot distribution, etc. ) to optimize the winding layout. The active method uses two identical windings shifted in space and fed by currents shifted in time in a manner that the MMF waveforms produced by the two windings will be in phase for the torque harmonic and in opposite phase for the undesirable harmonic ranks. These two methods have been applied to optimize the winding layout of the permanent magnet machine with a 12×nbase slots/10×nbase poles (nbase is an integer number). Two new winding layouts were then obtained. Permanent magnet machines with the optimized windings are then designed for a 10 kW-50rpm application. The electromagnetic performances of the optimized windings are investigated and compared with conventional winding topology. It is found that the proposed approaches allow the emergence of new windings with higher performances
Meile, Jean-Christophe. "Exploration fonctionnelle des machines moléculaires chez Bacillus subtilis : relations entre localisations sub-cellulaires et interactions protéiques." Paris 11, 2006. http://www.theses.fr/2006PA112056.
Full textBacterial cells were traditionally believed to be devoided of any subcellular organization. However, recent cytological studies revealed that proteins involved in essential processes such as DNA replication and cell division were localized to discrete subcellular sites. Therefore, several essential processes appear compartimentzalized in bacteria. This supported the concept of molecular machines, which has been utilized to describe multi-protein complexes that act in the cell. However, protein localization has never been studied at a large scale in bacteria. I have developped a method allowing the high-throughput construction and analysis of GFP fusions in the model bacterium Bacillus subtilis. About a hundred proteins were targeted according to their protein interactions (revealed by the yeast two-hybrid system) with components of the DNA replication (replisome) and cell division (divisome) machineries of B. Subtilis. We aimed at studying relationship between subcellular localization and protein interaction and discovering new molecular machines. Our study allowed discrete localization patterns for about 40 proteins as well as new localisation patterns close to the membrane to be observed. A functional analysis of several proteins has been performed. Thus, the dissection of localization patterns was realized by identifying interaction partners responsible for localization. The combination of such approaches (protein interaction and protein localization) allows the compostion of molecular machines to be studied. In this way, our knowledge about bacterial subcellular organization coud be improved
Briant, Emmanuelle. "Mise au point et application de la technologie FALI (Fluorophore-Assisted Light Inactivation) à l'étude de moteurs moléculaires." Université Louis Pasteur (Strasbourg) (1971-2008), 2007. http://www.theses.fr/2007STR13182.
Full textTo improve our capacity to analyze the role of multifonctional proteins involved in the cellular division, we decided to develop the FALI technology (Fluorophore-Assisted Light Inactivation). The principle of FALI is to tag a fluorophore to a protein of interest. The controlled illumination of this fluorophore allows the production of free radicals which denature specifically and locally the tagged protein. To develop and to validate this technology we developed two approaches: a method in which we overexpress a protein tagged with a fluorophore (FlAsH reagent), and a method where the fluorophore (FITC or FlAsH) is brought by a single-chain antibody (ScFv). We thus confirmed the implication of ZW10 protein in the transport of Golgi fragments, showing also that we manage to develop FALI. We also could show for the first time the implication of LIS1 protein in this same mechanism. Our first FALI experiments to study the fast poleward movement of chromosomes mediated by dynein in U2OS cells could not be carried out because of the too great toxicity of the labeling. These experiments show the importance to test the toxicity of the biarsenical ligands for each cell line and each protein we want to study
Gheith, Ramla. "Etude expérimentale et théorique des moteurs Stirling à apport de chaleur externe : application aux machines de types Bêta et Gamma." Nantes, 2011. http://archive.bu.univ-nantes.fr/pollux/show.action?id=b34f6a93-58df-4c78-9358-5d3fc2d9c183.
Full textZigon, Nicolas. "Synthèse et étude de tourniquets moléculaires et conception de MOFs à base de Pt (II)." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAF036/document.
Full textThe control of intramolecular movements has been a topic of high interest for chemists over two decades. Investigations described in this PhD manuscript aim at the design and study, both in solution and in the crystalline state, of molecular turnstiles. These entities are composed of a rotor and a stator, each of these constituents equipped with recognition sites.In the first part, the synthesis and behavior of Pt(II)-based molecular turnstiles are described. The switching between their open and closed states and the migration process between stations are discussed. The recognition sites on both the stator and rotor have been varied, leading to different behaviors, particularly in terms of their dynamics.In solution, 1- and 2-D NMR have been used for the characterization of the dynamic processes.In the last chapter, the use of a Pt(II)-bispyridyl based tecton for the synthesis of MM’OFs is reported. The use of various metal salts as secondary center has led to the construction of networks varying by their geometry and dimensionality. A ligand including two Pt(II) and one Fe(II) complexed by two terpyridyl units is described
Bastien, Guillaume. "Synthèse, structure et dynamique de rotors moléculaires cristallins." Phd thesis, Angers, 2013. https://theses.hal.science/tel-01064323.
Full textIn the context of spectacular developments in the field of molecular machines, the purpose of this work is to construct crystalline amphidynamic solids incorporating functional 1,4-diethynylbicyclo[2. 2. 2]octane (BCO) that are either self-assembled or organized by coordination to a metal. These chiral rotors have two degrees of freedom characterized in the solid state by variable temperature 1H spin-lattice relaxation experiments (rotational degree of freedom) or second-harmonic generation experiments (torsional degree of freedom of the helix blades). By coupling solid-state NMR experiments on static polycrystalline samples (experimental rotational barriers and frequency of rotational motion) to intermolecular interaction energy calculations of a rotor with its environment (rotational barriers), we show how the analysis of hydrogen bonding interactions is essential to understand the dynamics of the systems. In parallel, the non-linear optical nonlinearities recorded for every single crystalline rotor is seen as evidence for a random dynamic conformational switching in the handedness of the rotor helices which can undergo mutations while preserving the average space inversion symmetry of the lattice. In order to exploit this property, strategies of organic synthesis and crystal engineering have been implemented to direct the self-assembly of the rotators thereby providing objects for which the presence of a nonlinear optical response may be correlated with the dimensionality of the system
Khediri, Jalel. "Alimentation et commande d'un actionneur linéaire triphasé à flux transversal." Lille 1, 1986. http://www.theses.fr/1986LIL10072.
Full textGagnon, Éric. "Un modèle de prédiction et de classification des visites moteurs basé sur les machines à vecteur de support." Mémoire, Université de Sherbrooke, 2010. http://savoirs.usherbrooke.ca/handle/11143/4857.
Full textGuskov, Mikhail. "Dynamique non-linéaire des systèmes multi-rotors : Etudes numérique et expérimentale." Ecully, Ecole centrale de Lyon, 2007. http://bibli.ec-lyon.fr/exl-doc/mguskov.pdf.
Full textModern trends in the progress of the machine design are to increase performances while reducing mass. This causes augmented loads in machine parts while the compliances grow as well. The resulting dynamical responses occur at accrued levels, putting forward nonlinear phenomena. The aim of this thesis is to study nonlinear structural dynamics, especially in view of application to multi-shaft aircraft engines rotordynamics. This problematics is investigated by theory and experiment. As for the theoretical development, we adress the dynamical response of strongly nonlinear systems under multi-frequency excitations. To this aim, the models of roller bearings are studied and implemented from the point of view of application to rotordynamics computations. In particular, these models take radial clearance and nonlinear contact stigness into account. In order to deal with multiple unbalance excitations which are present in multi-shaft rotor systems, we have elaborated a generalized harmonic balance approach so as to predict the resulting quasi-periodic motions. This work has been applied to a dual shaft test rig with an intershaft bearing built during this study. Methods of stability evaluation are also considered in view of extensions to quasi-periodic motions. In the experimental part of the work, we have designed and studied a dual shaft test rig with an intershaft bearing. The overall modal analysis of this rig matches a real aircraft engine's rotordynamical behavior. After the design and construction of the rig, several operational configurations have been tested. Firstly, we have studied the unbalance response of the machine under the nominal co-rotating conditions in order to validate the design approach and estimate the residual unbalance of the machine. Secondly, the counter-rotating operation has been tested. Finally, an additional mass has been mounted on one of the shafts. This has allowed to lower one of the modes into the operational range of the machine. The overall test results have enabled the observations of dynamical phenomena typical for the dual shaft dynamics both from the rotordynamical and nonlinear points of view : forward and backward whirls, quasi-periodic precession motion, resonance peaks distorsion and superharmonic response
Flasquelle, Aurélie. "Contribution à la modélisation multi-physique : électro-vibro-acoustique et aérothermique de machines de traction." Ecole Centrale de Lille, 2007. http://tel.archives-ouvertes.fr/docs/00/19/65/74/PDF/These-A_FASQUELLE.pdf.
Full textTransports have been developed for past few years. This major development has been followed by growing concern for the environment respect. Although railway transports present high energy efficiency, they also present environmental nuisances. It is then necessary to include the sustainable development from the moment of conception. It results in the consideration of numerous physical phenomena. Consequently, this PhD Thesis aims to emphasize a conception methodology in respect to the current will of economic and ecological optimisation. Then, a multi-physical model has been developed in order to represent electromagnetic, acoustic and thermal-flow phenomena in an enclosed induction motor of railway traction. In fact, this model is divided into several analytical interacting models. Each model represents a specific physical phenomenon. This work focuses on the thermal-flow model and the losses model, and in particular on the modelling of the iron losses. Although these models are analytical models, they both rely on numerical studies. The multi-physical model has shown to be efficient and to respect the main evolution trends thanks to comparison with experimental results and analysis of the uncertainties influence
Dib, Rabih. "Caractérisation vibratoire des machines industrielles par des méthodes pseudo-inverses : méthodologie, instrumentation et expérimentation." Compiègne, 2002. http://www.theses.fr/2002COMP1424.
Full textRiss, yaw Benjamin. "Des Synthons Entrelacés pour la Préparation Efficace de Machines Moléculaires et de Rotaxanes Dénués de Site de Reconnaissance." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS143.
Full textThis thesis is dedicated to the synthesis of interlocked synthons for the efficient preparation of pH-sensitive rotaxane molecular machines and rotaxanes devoid of recognition site. Although the strategy directed by the "template" effect has been used very frequently and successfully so far, in most cases it only leads to interlocked compounds that contain the interaction sites necessary for prior recognition molecular elements to assemble. To overcome this limitation, a new direct access using interlocked synthons for the preparation of molecular machines of the rotaxane and rotaxane type devoid of strong interaction sites has been studied. Firstly, isolable [2]rotaxane "building block", although activated, were obtained by a slipping strategy. In order to easily convert them into molecular machines, the kinetic and thermodynamic parameters relating to the slipping process were determined and made it possible to judge the importance of the nature and orientation of the pseudo-stopper on the kinetics of slipping, as well as the primordial role of the degree of conformational freedom of the molecular axis on the speed of formation of rotaxanes. Subsequently, the activated ester (NHS isolatable ester) interlocked synthon are used in the preparation of different molecular machines having a main ammonium molecular station and a secondary molecular triazolium or amide station (secondary or tertiary). Other interlocked synthons that differ in the orientation of the NHS motif are used as crown ether transporters to enable the preparation of rotaxanes devoid strong interaction sites. Finally, in the continuity of the work carried out in the laboratory on the control of the chair conformation of a mannosyl by a molecular machinery, new pH-sensitive shuttles of glyco[2]rotaxane containing a main molecular station anilinium, and which different previous machines by the second station pyridinium, were obtained and studied
Bastien, Guillaume. "Synthèse, structure et dynamique de rotors moléculaires cristallins." Phd thesis, Université d'Angers, 2013. http://tel.archives-ouvertes.fr/tel-01064323.
Full textMarques, Christine. "Dégénérescence des neurones moteurs cortico-spinaux dans un modèle murin de sclérose latérale amyotrophique : dynamique spatio-temporelle et mécanismes moléculaires." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAJ063/document.
Full textAmyotrophic lateral sclerosis (ALS) is clinically defined as the combined degeneration of the corticospinal motor neurons (CSMN) along with the bulbar and spinal motor neurons (BMN and SMN). While a growing body of evidence points to the cerebral cortex as the potential initiation site of ALS, little is known about the cortical pathology, the spatio-temporal dynamics of CSMN degeneration, and the molecular pathways involved. This thesis work aimed at filling this knowledge gap. In Sod1G86R, we showed that CSMN loss seems to take place without major gliosis, occurs in a somatotopic manner and precedes motor symptom appearance and SMN degeneration. We purified, thanks to the development of a novel protocol, adult CSMN from the cerebral cortex of healthy or diseased mice from early presymptomatic ages to the end stage of the disease. The RNA-seq analysis has made it possible to identify new and early molecular players in ALS. This would provide a foundation for the development of therapeutic approaches based on the maintenance of healthy and functional CSMN, and, on the long run, may in turn inform the development of alternative therapeutic strategies for ALS
Bouscayrol, Alain. "Structures d'alimentation et stratégies de commande pour des systèmes multimachines asynchrones : application à la motorisation d'un robot mobile." Toulouse, INPT, 1995. http://www.theses.fr/1995INPT008H.
Full textAt the present time, several systems use multiple induction machines, which are supplied by independant inverters and are controlled with different microprocessors. This work leads to develop multimachine systems with a reduction of the number of power components and simplified algoritm controls. So, multimachine inverters (with m inverter legs for n machines) are constitued by the using of a special and general pattern. Four classes of multimachine inverter are proposed and studied. Then, a direct vector control with a flux observer, called cartesian control, is introduced for only one induction motor. Two original multimachine controls are deduced from the classical independant controls of several machines, and authorise an algorithm reduction. The diverse combinations of supply and control are realised in a modular way, and are applied to a bimachine motorisation set for a mobile robot. An experimental realisation validate one of this configuration by the using of only one standard microprocessor (Motorola MC 68000)
Clénet, Stéphane. "Influence de l'alimentation électronique sur le couple et le comportement vibratoire des machines synchrones à aimants permanents." Toulouse, INPT, 1993. http://www.theses.fr/1993INPT121H.
Full textDemirjian, Razmik. "Contribution au développement et à l'optimisation des machines électriques à courant continu pour des applications Stop-Start." Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-01024453.
Full textTual, Séverine. "Rôle des expositions professionnelles en milieu agricole sur des pathologies respiratoires cancéreuses et non cancéreuses." Caen, 2013. http://www.theses.fr/2013CAEN4077.
Full textAgricultural workers are exposed to a large spectrum of agents (organic dusts and its components, pesticides, engine exhaust fumes). For some respiratory diseases, some of these exposures might be deleterious or protective according to the time window of exposure. The aim of this work was to assess the role of some agricultural exposures (direct and indirect exposures to pesticides and engine exhaust fumes) on lung cancer risk and chronic bronchitis risk. Analyses relied on the cohorts AGRICAN (nearly 180,000 subjects affiliated to the French Health insurance scheme in agriculture, 11 areas, 388 lung cancer cases) and AHS (nearly 50 000 farmers and their spouses, 2 US States, 441 lung cancer cases). A cross sectional study on the respiratory health of 322 active agricultural workers was also carried out in Calvados (France). After controlling for smoking, a 50%-decreased risk of lung cancer was observed among cattle breeders (≥ 30 years of work). Increased risks of lung cancer were associated with harvesting field peas, cutting fruit trees and with the daily driving of diesel tractors among crop producers (more than 2-fold increased risks). Higher risks of chronic bronchitis were also observed among cattle breeders and potatoes producers in France. Upcoming analyses will attempt to assess the role of specific pesticides on the respiratory health of farmers and agricultural workers in France, using the matrix Pestimat. Further efforts will focus on the identification of determinants of deleterious exposures (direct and indirect exposures to pesticides, exposure to organic dusts and to engine exhaust fumes)
Krebs, Guillaume. "Étude, conception et réalisation d'un actionneur électromagnétique à mouvements linéaire et rotatif." Lille 1, 2007. http://www.theses.fr/2007LIL10155.
Full textPlaud, Clément. "Mécanismes moléculaires et cellulaires des paraplégies spastiques héréditaires liées aux mutations du gène SPG4 : haploinsuffisance VS gain de fonction pathologique." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLE037/document.
Full textCentral motor neurons are specialized cells involved in the control of voluntary movements in human. The transmission of information along the axon of these neurons is comparable to car trafficking in a highway: information travel in both direction and sometimes traffic jam events occur. When the transit of information are slowed or impaired, patients may suffer of neurodegenerative diseases as hereditary spastic paraplegia (HSPs). In this thesis we investigated the role of spastin, a protein implicated in HSP and the maintenance of these highways. Our results showed that depletion of spastin, or expression of its mutants, lead to a disturbance of both the integrity of these « road » and the traffic of cellular components primary involved in axonal survival and growth. These results would help to elucidate the pathophysiological mechanisms implicated in the onset of this pathology and maybe in developing proficient therapeutic strategy for HSP patients
Guenet, Aurélie. "Un portail moléculaire basé sur une porphyrine à anse : Synthèse, étude et premier pas vers le développement de machines moléculaires." Strasbourg 1, 2007. https://publication-theses.unistra.fr/public/theses_doctorat/2007/GUENET_Aurelie_2007.pdf.
Full textThis monograph describes the synthesis of a molecular gate. The design of the gate is based on a tin porphyrin, the hinge, bearing a coordination site oriented away from its centre, and a handle whose coordination site is oriented towards the hinge. As long as the handle swivels freely around the hinge, the gate is said to be opened. The closing of the gate occurs through simultaneous coordination of both interaction sites located on the hinge and on the handle. The first chapter deals with the study of the hinge alone. The next two chapters are devoted to the actual synthesis of two types of molecular gates depending on the denticity of the coordination site on the handle. In the case of the gate based on a monodentate site, the closing and opening processes of the gate are achieved upon addition of silver cation and bromide anion respectively. The gate based on a tridentate coordination site is in the closed position thanks to the establishment of intramolecular hydrogen bonds
Tounsi, Bayram Astier Stéphan. "Étude comparative de groupes électrogènes embarqués à large gamme de vitesse variable associant machines à aimants permanents et conversion statique." Toulouse : INP Toulouse, 2007. http://ethesis.inp-toulouse.fr/archive/00000380.
Full textChauveau, Éric. "Contribution au calcul electromagnetique et thermique des machines electriques application a l'etude de l'influence des harmoniques sur l'echauffement des moteurs asynchrones." Nantes, 2001. https://hal.archives-ouvertes.fr/tel-01959857.
Full textHenry, Thomas. "Physiologie de S. Typhimurium dans l'environnement intracellulaire : la division bactérienne et la modulation des moteurs moléculaires eucaryotes sur la vacuole contenant Salmonella." Aix-Marseille 2, 2005. http://theses.univ-amu.fr.lama.univ-amu.fr/2005AIX22030.pdf.
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