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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

[en] AUTONOMOUS SYSTEMS EXPLAINABLE THROUGH DATA PROVENANCE / [pt] SISTEMAS AUTÔNOMOS EXPLICÁVEIS POR MEIO DE PROVENIÊNCIA DE DADOS

TASSIO FERENZINI MARTINS SIRQUEIRA 25 June 2020 (has links)
[pt] Determinar a proveniência dos dados, isto é, o processo que levou a esses dados, é vital em muitas áreas, especialmente quando é essencial que os resultados ou ações sejam confiáveis. Com o crescente número de aplicações baseadas em inteligência artificial, criou-se a necessidade de torná-las capazes de explicar seu comportamento e responder às suas decisões. Isso é um desafio, especialmente se as aplicações forem distribuídas e compostas de vários agentes autônomos, formando um Sistema Multiagente (SMA). Uma maneira fundamental de tornar tais sistemas explicáveis é rastrear o comportamento do agente, isto é, registrar a origem de suas ações e raciocínios, como em uma depuração onisciente. Embora a ideia de proveniência já tenha sido explorada em alguns contextos, ela não foi extensivamente explorada no contexto de SMA, deixando muitas questões para serem compreendidas e abordadas. Nosso objetivo neste trabalho é justificar a importância da proveniência dos dados para SMA, discutindo quais perguntas podem ser respondidas em relação ao comportamento do SMA, utilizando a proveniência e ilustrando, através de cenários de aplicação, os benefícios que a proveniência proporciona para responder a essas questões. Este estudo envolve a criação de um framework de software, chamado FProvW3C, que suporta a coleta e armazenamento da proveniência dos dados produzidos pelo SMA, que foi integrado a plataforma BDI4JADE (41), formando o que denominamos de Prov-BDI4JADE. Por meio desta plataforma, utilizando exemplos de sistemas autônomos, demostramos com rigor que, o uso da proveniência de dados em SMA é uma solução sólida, para tornar transparente o processo de raciocínio e ação do agente. / [en] Determining the data provenance, that is, the process that led to those data, is vital in many areas, especially when it is essential that the results or actions be reliable. With the increasing number of applications based on artificial intelligence, the need has been created to make them capable of explaining their behavior and be responsive to their decisions. This is a challenge especially if the applications are distributed, and composed of multiple autonomous agents, forming a Multiagent System (MAS). A key way of making such systems explicable is to track the agent s behavior, that is, to record the source of their actions and reasoning, as in an omniscient debugging. Although the idea of provenance has already been explored in some contexts, it has not been extensively explored in the context of MAS, leaving many questions to be understood and addressed. Our objective in this work is to justify the importance of the data provenance to MAS, discussing which questions can be answered regarding the behavior of MAS using the provenance and illustrating, through application scenarios, to demonstrate the benefits that provenance provides to reply to these questions. This study involves the creation of a software framework, called FProvW3C, which supports the collects and stores the provenance of the data produced by the MAS, which was integrated with the platform BDI4JADE (41), forming what we call Prov-BDI4JADE. Through this platform, using examples of autonomous systems, we have rigorously demonstrated that the use of data provenance in MAS is a solid solution to make the agent’s reasoning and action process transparent.
252

Method development for biomolecular solid-state NMR spectroscopy

Asami, Sam 17 October 2014 (has links)
Im Rahmen der vorliegenden Arbeit, wird ein neuartiges Markierungsschema für die Festkörper-NMR-Spektroskopie vorgestellt, das sogenannte Reduced Adjoining Protonation (RAP) Schema, welches die Protonendetektion sämtlicher Aliphaten erlaubt. Hochaufgelöste, 1H-detektierte 1H,13C Korrelationsspektren wurden erhalten. Des Weiteren wurde der Vorteil von hohen MAS-Frequenzen untersucht. 1H- und 13C-detektierte 3D Zuordnungsexperimente wurden implementiert, welche uns die Zuordnung von 90% aller aliphatischen Resonanzen von alpha-Spektrin SH3 erlaubten. Da die chemische Verschiebung abhängt vom Strukturmotiv, kann sie verwendet werden, um Sekundärstruktur-Informationen abzuleiten. Darüber hinaus wurde ein 1H-detektiertes H(H)CH 3D Experiment entwickelt, um weitreichende 1H,1H Kontakte zu ermitteln, welche für die Bestimmung der Tertiärstruktur genutzt werden können. Um artefaktfreie Relaxationsdaten zu erhalten, wurde das RAP-Markierungsschema modifiziert, um 1H- und 13C-verdünnte Proben zu erhalten, in denen Spindiffusion unterdrückt ist. Für die Untersuchung von Sub-Mikrosekunden-Dynamik werden Experimente vorgestellt zur Bestimmung von 13C T1 Relaxationszeiten und 1H,13C dipolaren Kopplungstensoren für Rückgrat- und Seitenketten-Resonanzen. Des weiteren zeigen wir, dass das RAP-Markierungsschema auf nicht-kristalline Systeme, wie Amyloidfibrillen des Abeta1-40 Peptids der Alzheimer-Krankheit, angewendet werden kann. Unter Verwendung von 1H-Detektion, erhielten wir hochaufgelöste 1H,13C Korrelationsspektren. Schließlich wurde der Perdeuterierungsansatz auf den L7Ae-box C/D Protein-RNA Komplex aus P. furiosus angewendet. Wir erhielten hochaufgelöste, 1H-detektierte 1H,15N, sowie 13C,13C Korrelationsspektren des Protein-RNA Komplexes. Weiterhin haben wir eine Methode zur Bestimmung genauer Abstands- und Winkelinformationen für die Protein-RNA Schnittstelle etabliert und schlagen Ansätze vor, für die Zuordnung der chemischen Verschiebungen von RNA-Resonanzen. / In this thesis, a novel labeling scheme for solid-state NMR spectroscopy, the Reduced Adjoining Protonation (RAP) scheme, is introduced, which allows proton detection of all aliphatic sites, as shown for the microcrystalline SH3 domain of alpha-spectrin. These samples yield high-resolution, 1H-detected 1H,13C correlation spectra. In addition, the benefit of high MAS frequencies was investigated. 1H- and 13C-detected 3D assignment experiments are implemented, which allowed us to assign 90% of all aliphatic resonances of alpha-spectrin SH3. As the chemical shift is dependent on the structural motif, it can be employed to derive secondary structure information. Furthermore, a 1H-detected H(H)CH 3D experiment is introduced, to obtain long-range 1H,1H contacts, which can be used for the determination of the tertiary structure. To obtain artifact-free relaxation data, the RAP labeling scheme was modified to obtain sparsely proton labeled, 13C dilute samples, in which spin diffusion is suppressed. To probe sub-microsecond dynamics, we report experiments to determine 13C T1 relaxation times and 1H,13C dipolar coupling tensors for backbone and side chain resonances, respectively. Furthermore, we show, that the RAP labeling scheme can be applied to non-crystalline systems, such as amyloid fibrils of the Alzheimer’s disease peptide Abeta1-40. Using 1H-detection, we obtained high-resolution 1H,13C correlation spectra. Finally, we applied the perdeuteration approach to the L7Ae-box C/D protein-RNA complex from P. furiosus. We obtained high-resolution, 1H-detected 1H,15N, as well as 13C,13C correlation spectra of the protein-RNA complex. In addition, we established a methodology to determine accurate distance and angular restraints for the protein-RNA interface and propose approaches for the chemical shift assignment of RNA resonances.
253

Contributions à l’étude de machines multi-enroulements pour l’aéronautique : machine synchrone à aimants permanents pour la tolérance aux défauts : machine asynchrone pour la traction / Contributions to the study of multi-winding machines for aeronautic : Permanent Magnet synchronous Motor for fault tolerant applications : Asynchronous motor for Taxiing

Velly, Nicolas 06 April 2011 (has links)
Le projet d'avion électrique vise à remplacer les vecteurs énergétiques que sont les fluides hydrauliques et l'air comprimé par le courant électrique et d'obtenir en conséquence une diminution significative de la consommation en carburant Dans cette thèse, nous proposons deux solutions : la première dans un souci d'accroitre la disponibilités des actionneurs électriques et la seconde pour la traction au sol (taxiage d'avion). Dans la première étude, nous nous plaçons dans le cadre d'un actionneur pour lequel il est demandé une redondance électrique. Ceci peut être le cas d'un actionneur de mode « normal », redondé par un actionneur de type secours, mais où les fiabilités cumulées ne sont pas suffisantes, et où la partie électrique et la commande du système dit normal est redondé. Nous proposons une topologie de moteur synchrone à aimants permanents à bobinage à plots à deux étoiles découplées magnétiquement et à courant de court-circuit limité. Pour les machines à plots, nous avons établi un modèle semi analytique dans le but de prédire l'amplitude de la résultante des forces radiales agissant sur le rotor de cette machine en cas de fonctionnement en modes sain et dégradé. Nous avons établi le modèle de cette machine en vue de la commande et nous avons validé expérimentalement ce principe de conception sur un prototype dimensionné au laboratoire et réalisé par une société du groupe SAFRAN. Dans la seconde étude, nous avons investigué sur l'utilisation de moteurs multi-enroulements permettant de répondre au mieux à un cahier des charges exigeant pour une application de traction d'aéronefs: le « green taxiing ». Le principe est de permettre de faire varier le coefficient de couple d'un moteur de manière à optimiser la masse du moteur mais aussi les contraintes sur le convertisseur qui l'alimente permettant d'atteindre de larges plages de vitesse. Le modèle en vue de l'alimentation a été développé et validé par une comparaison à une résolution par éléments finis en magnétodynamique / The more electrical aircraft project aims at replacing most of current power generation sources by electrical ones. Consequently this replacement might generate a significant decrease of the fuel consumption. Through this thesis we determine two electrical solutions allowing on the one hand the increase of disponibility level of the actuators and on the other handthe aircraft taxiing by electrical means. We firstly focused on electrical actuators that require electrical redundancy. A first mean to achieve this redundancy is to use two actuators. Nevertheless this solution is not relevant under the reliability constraint because the global failure rate is increased. A double star permanent magnet synchronous motor with concentrated winding is proposed in which a special care was taken to the short circuit current limitation and the magnetic decoupling between the two star winding. We established a semi-analytic model for this kind of motors to predict the amplitude of the resultant of the radial forces acting on the rotor of the machine when operating under normal and faulty operation. We established the model of the machine in order to determine the command strategy. We experimentally validated all of the design principles mentioned above through a prototype designed in the laboratory and built by one of the SAFRAN group company. We secondly investigated on the way to apply the multi winding principles to a brand new project linked to the aircraft taxiing called “green taxiing”. The goal is to obtain a motor topology that allows operating on a wide speed range thanks to the command strategy and the change of its torque coefficient. We established the model of the machine and we compared the results given by this ingenious model to the results given by a finite element resolution using a transient magnetic application
254

Etude métabolomique par résonance magnétique nucléaire de pathologies associées à la signalisation thyroïdienne chez la souris / The application of metabolomics by high field nuclear magnetic resonance to study thyroid signalisation pathologies in mice

Boumaza, Houda 08 March 2019 (has links)
La métabolomique par résonance magnétique nucléaire (RMN) permet d’étudier laréponse métabolique globale d’un système biologique à un stimulus ou un événementphysiopathologique (maladie, manipulation génétique, etc.). Cette discipline connaît un essorimportant dans la recherche clinique et biologique, et constitue ainsi un outil à fort potentielpour la découverte de biomarqueurs de maladies, et l’étude de la fonction des gènes.Cette thèse est dédiée à l’application de la métabolomique par RMN à hauts champspour l’étude des pathologies associées à la signalisation thyroïdienne chez la souris. L’objectifglobal est d’identifier des biomarqueurs spécifiques liés aux différentes maladies hormonales :l’hypothyroïdie et la maladie génétique émergente résistance à l’hormone thyroïdienne due àune mutation au niveau du récepteur TRα1 (RTHα). Cette dernière est particulièrementdifficile à diagnostiquer à cause du manque de marqueurs biochimiques et de symptômesspécifiques à cette maladie. De plus, elle présente des similitudes avec l’hypothyroïdie auniveau symptomatique. Des modèles murins de RTHα et de l’hypothyroïdie ont été analysés,et l’investigation a été menée sur l’urine et le plasma sanguin dans le but de différenciermétaboliquement ces maladies et d’identifier des biomarqueurs spécifiques à RTHα. Dessignatures métaboliques liées à chaque maladie ont été identifiées dans l’urine et le plasmasanguin. Cinq métabolites qui varient de façon significative ont été identifiés dans l’urinecomme étant liés à la maladie RTHα : trimethylamine, dimethylamine, isovalerylglycine, Nacetylglucosamineet la choline. Dans le sang, ce sont les lipides insaturés qui varient de façonsignificative chez les souris mimant la maladie RTHα. / Metabolomics by nuclear magnetic resonance (NMR) allows studying the metabolicresponse of a global biological system to a stimuli or a physiopathological even (diseases,genetic modifications, etc.). This discipline is growing especially in the clinical and biologicalfields, and represents a strong potential tool to identify biomarkers related to diseases, andstudy the function of genes.This thesis is dedicated to the application of metabolomics by high field NMR to studythyroid signalisation pathologies in mice. The main goal is to identify biomarkers related tothe emerging genetic disease called resistance to thyroid hormone due to a mutation in thyroidhormone receptor TRα1 (RTHα). This disease is particularly difficult to diagnose because ofthe lack of biochemical markers and specific symptoms. In addition, it presents commonfeatures with hypothyroidism in term of symptoms. Mice models of RTHα andhypothyroidism were analysed, and the investigation were driven on urine and blood plasmain order to differentiate metabolically theses diseases and identify biomarkers related toRTHα. Metabolic fingerprints related to each disease were identified in both urine and bloodplasma. Five metabolites vary significantly in the urine of RTHα mice: trimethylamine,dimethylamine, isovalerylglycine, N-acetylglucosamine and choline. Unsaturated lipids varysignificantly in the blood plasma of RTHα mice.The impact of thyroid hormones (TH) and the thyroid hormone receptor TRβ on theliver metabolism were also studied in the present manuscript through NMR-basedmetabolomics. A mouse model, with a specific knock-out of TRβ gene in hepatocytes (LTRβ-KO), were used to study this question. To understand the function of TH mediated by TRβ,the liver metabolic response to TH, obtained from liver aqueous extracts and intact livertissues, TRβKO and wild-type mice were compared. The results suggest the presence ofdirect and indirect effects of thyroid hormones on the liver metabolism.
255

Etude des conditions de confinement du plomb et du cadmium dans des verres à base de métaphosphates de zinc

El Hadrami, Abdelouahab 26 June 2003 (has links) (PDF)
Dans le cadre du confinement des métaux lourds toxiques à savoir Pb et Cd, cette étude a porté sur la recherche de nouveaux verres phosphates présentant des propriétés physico-chimiques optimisées. Des verres de composition (100-x) (50P2O5-15ZnO-35PbO)-xFe2O3 et (100-z) [50P2O5-15ZnO-(35-y)PbO-yCdO]-zAl2O3 ont été élaborés. L'introduction des oxydes de fer et d'aluminium dans les matrices phosphatées entraîne une amélioration des propriétés et en particulier un renforcement de la durabilité chimique, en milieu aqueux, comparable à celle des verres silicates. Ces résultats ont pu être corrélés à la formation d'un réseau mixte fortement réticulé dans lequel les cations présentant une coordinence multiple forment des liaisons covalentes à caractère élevé avec les atomes d'oxygène. Avec une température de transition vitreuse modérée, ces verres sont des candidats potentiels pour le stockage d'éléments lourds toxiques.
256

Romance vs novela : recuperación y renovación de la materia caballeresca en la novela española del siglo XX: de "Morsamor" (1899) a "Olvidado Rey Gudú" (1996)

Pérez Abellán, María Encarnación 14 September 2012 (has links)
El trabajo de investigación presente ha pretendido establecer conexiones temáticas y formales, pero también divergencias argumentales y estructurales entre el planteamiento de la materia caballeresca medieval y áurea en la Literatura española, y su recuperación renovada a lo largo del pasado siglo XX. La inmanencia de motivos y tópicos permitirá adaptarla formalmente a los géneros históricos, desplegando un recorrido desde el primitivo roman hasta la actual novela, sin olvidar la sólida presencia del romance caballeresco o el influjo que las contemporáneas novela lírica, histórica o bildungsroman han ejercido hasta conferirles plena singularidad. Éste es el objetivo perseguido en el análisis de obras significativas de Juan Valera (Morsamor, 1899), Benjamín Jarnés (Viviana y Merlín, 1930), Álvaro Cunqueiro (Merlín y familia, 1955), Manuel Mujica Láinez (El unicornio, 1965), Paloma Díaz-Mas (La búsqueda del Santo Grial, 1983), Soledad Puértolas (La rosa de plata, 1999) y Ana María Matute (Olvidado Rey Gudú, 1996) / he main proposal of this research has been connecting the ancient chivalry plots with a group of modern Spanish novels, which present interesting and similar points of view, however important differences. It is pretended searching how the materials have been treated in similar ways, as well as how it has been looked for the narrative strategies that have allowed creating singular novels. Historical and lyrical novels, bildungsroman, even tales, will have influenced in these last ones along the past twentieth century.
257

Modellierung und Evaluierung von Multiagentensystemen im Kontext von Kooperationsproblemen / Modelling and analysis of multiagent systems concerning cooperation problems

Reinhold, Thomas 28 February 2005 (has links) (PDF)
The subject of this diploma thesis is the modelling and the analysis of mechanisms that enable multiagentsystems to establish communication relations and using them to control the interaction. With regards to the emergence of such symbol systems one groundwork of this paper is the realization that coordination problems aren't applicative to advance to evolution of "higher communication capabilities". With this in mind, this analysis uses a class of problems with explicit conflicts of interests between agents and the necessity of solving such interaction problems with the help of communication. The paper determines and discusses mechanisms and constraints that enable multiagentsystems to evolve such self-organisating social structures as well as preserving them. / Thema dieser Diplomarbeit ist die Modellierung und Untersuchung von Mechanismen, auf deren Grundlage Multiagentensysteme in der Lage sind, Kommunikationsbeziehungen aufzubauen und kommunikative Akte interaktionssteuernd zu verwenden. Hinsichtlich der Emergenz derartiger Symbolsysteme besteht eine wesentliche Erkenntnis, auf der diese Arbeit aufbaut, darin, dass Koordinationsprobleme als Kontext für MAS kein geeignetes experimentelles Umfeld für die Herausbildung "höherer kommunikativer Fähigkeiten" darstellen. Davon ausgehend werden für eine Klasse von Problemen, in denen die Abstimmung über eine Interaktion aufgrund von Interessenkonflikten einen expliziten Teil des kommunikativ zu lösenden Problems darstellt, Mechanismen und Constraints herausgearbeitet und diskutiert, die Agenten in die Lage versetzen, ein sich selbst organisierendes soziales Gefüge aufzubauen und zu erhalten.
258

Formy vzájemné spolupráce kooperačních sdružení / Forms of Mutual Collaboration of Cooperation Associations

BLÁHOVÁ, Jana January 2011 (has links)
The main aim of this thesis was to analyze the cooperation between Local Action Groups in the Czech Republic. From the time perspective to determine, whether LAG is trying to cooperate more among themselves and thus gain even more financial resources to ongoing Cooperation projects. The other objectives of the second part is devoted to the thesis, which is specifically focused on the cooperation project called ?Rural Market II?, which was implemented under the cooperation of six participating LAGs. The mentioned project was based on the cooperation of six Local Action Groups and the main goal is to encourage local entrepreneurs in the territorial specific LAG. As an interim target was set an objective assessment of gaps in data collection in the catalog business, which was implemented under the Rural Market II.
259

ESPECIFICAÇÃO DE UMA SOCIEDADE DE AGENTES PARA UM SISTEMA DE APRENDIZAGEM COOPERATIVA À DISTÂNCIA / SPECIFICATION OF A SOCIETY OF AGENTS FOR A SYSTEM OF COOPERATIVE DISTANCE LEARNING

Magalhães, Yonara Costa 31 January 2003 (has links)
Made available in DSpace on 2016-08-17T14:52:45Z (GMT). No. of bitstreams: 1 Yonara Magalhaes.pdf: 3488130 bytes, checksum: e183eccb37268ce608c84048d98d467a (MD5) Previous issue date: 2003-01-31 / Cooperative process of teach-learning at a distance of the society of intelligent agents of environment MATHNET. It is presented architecture of the society of agents of the MATHNET that to provide the process with teach-learning. It is in exchange for distinguished the Tutor Agent and the model of communication, based messages and that it uses the FIPA-ACL Agent Communication Language, between the Tutor Agent and excessively the participant agents of this society. The main characteristics and the paper (responsibilities) of the Tutor Agent describe. Its conceptual model is constructed. Its main Cases Use, interactions with several agents of this architecture and the protocols of communication of the Tutor Agent with the other agents are shaped. The Tutor Agent creates itself using a tool of construction of agents. One implements the Tutor Agent and its Cases Use to inside demonstrate to its relevance and importance of the system and the model of communication. / Processo de ensino-aprendizagem cooperativo à distância da sociedade de agentes inteligentes do ambiente MATHNET. Apresenta-se a arquitetura da sociedade de agentes do MATHNET que provê o processo de ensino-aprendizagem. Destaca-se o Agente Tutor e o modelo de comunicação, baseado em troca de mensagens e que utiliza a Linguagem de Comunicação FIPA-ACL, entre o Agente Tutor e os demais agentes participantes dessa sociedade. Descrevem-se as principais características e o papel (responsabilidades) do Agente Tutor. Constrói-se o seu modelo conceitual. Modelam-se os seus principais Casos de Uso, as interações com os demais agentes dessa arquitetura e os protocolos de comunicação do Agente Tutor com os outros agentes. Cria-se o Agente Tutor utilizando para isto uma ferramenta de construção de agentes. Implementa-se o Agente Tutor e seus Casos de Uso para demonstrar sua relevância e importância dentro do sistema e o modelo de comunicação aqui proposto.
260

Biodistribution and biological impact of nanoparticles using multimodality imaging techniques : (Magnetic resonance imaging) / Biodistribution et effet biologique des nanoparticules utilisant des techniques d’imagerie multimodale : (Imagerie de résonance magnétique)

Faraj, Achraf Al 30 June 2009 (has links)
En raison de leurs propriétés uniques, des nanoparticules industriellement fabriquées comme les nanotubes de carbone (NTC) ont révolutionné le domaine de la nanotechnologie. Il apparait nécessaire de développer des techniques d’investigation in vivo basées sur les propriétés intrinsèques de ces particules et permettant un suivi longitudinal pour évaluer leur risque après inhalation accidentelle par voie respiratoire. Un protocole d’IRM pulmonaire non-invasive utilisant l’hélium-3 hyper polarisé sous respiration spontanée a été développé en complément d’un protocole d’IRM systémique proton pour permettre la détection des NTC grâce à l’effet de susceptibilité magnétique induit par les impuretés de fer, associées aux nanotubes après leur exposition intra pulmonaire. Combiné avec l’IRM pulmonaire proton et des analyses en microscopie optique et électronique à différents temps d’investigation, ce protocole d’imagerie multimodale permet d’évaluer la biodistribution et l’impact biologique des NTC bruts après exposition intra pulmonaire.Une accentuation des réactions inflammatoires (granulomes multifocaux, dépôt de fibres de collagène…) avec le temps et la dose administrée a été observée.De l’évaluation de l’impact biologique des NTC après une exposition intra pulmonaire vers leurs applications biomédicales, les nanotubes de carbone avec leurs propriétés physicochimiques fascinantes et leur forme spécifique laissent entrevoir des applications potentielles en nanomédecine. La bio distribution et le profil pharmacologique des différents types de NTC ont été évalués longitudinalement par IRM et dosage dans le sang et les organes cibles après une injection intraveineuse, et leur impact biologique sur le métabolisme du foie a été examiné ex vivo par RMN haute résolution à l’angle magique (HR-MAS). Aucun signe de toxicité aiguë (variation du métabolisme du foie) n’a été observé et les analyses statistiques conduits sur les spectres RMN (tests PCA) ne montrent aucune différence entre les échantillons analysés et donc l’absence de discrimination entre les différents groupes par rapport aux animaux contrôles. / As novel engineered nanoparticles such as single-walled carbon nanotubes (SWCNT) are extensively used in nanotechnology due to their superior properties, it becomes critical to fully understand their biodistribution and effect when accidently inhaled. There fore, development of animaging technique which allow longitudinal in vivo follow-up of SWCNT effect based on their intrinsic properties is highly desirable. Non invasive free-breathing hyperpolarized 3He lung MRI protocol was developed complementary to proton systemic MR protocol to allow monitoring SWCNT based on their intrinsic iron impurities after intrapulmonary exposition. Combined toproton lung MRI and ex vivo optical and electron microscopy at different time points, this protocol represents a powerful multimodality imaging techniques which allows a full characterization of the biodistribution and biological impacts of iron containing SWCNT. SWCNT was found to produce granulomatous and inflammatory reactions in a time and dose dependent manner with their bio persistenc eafter intrapulmonary exposition.From biological impact evaluations after intrapulmonary exposition towards biomedical applications, SWCNT hold promise for applications in nanomedicine field with their distinct architecture and their novel physicochemical properties. The biodistribution and pharmacological profile of various well-dispersed pristine and functionalized SWCNT were assessed in blood and target tissues after their intra venous administration by longitudinal in vivo susceptibility weighted MRI and their potential effect on liver metabolism by ex vivo HRMAS 1H NMR. No presence ofacute toxicological effect (variation in liver metabolism) was observed confirmed by the absence of clustering in NMR spectra using Principal Component Analysis (specific biomarkers of toxicity).

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