L’arbre bronchique constitue une large interface avec le milieu extérieur ce qui en fait notamment une sentinelle immunologique. Par ailleurs, il est soumis à de multiples contraintes physiques (variation de pressions lors du cycle ventilatoire) avec le développement de pathologies lorsque la réponse à ces contraintes est inadaptée. Au cours de ce travail, nous avons essayé de caractériser la réponse bronchique des voies aériennes distales à partir d’un modèle isolé de bronche humaine soumis à l’application d’un stretch unique ou cyclique tel qu’il est généré lors de la ventilation mécanique. D’un point de vue fonctionnel, le stretch unique ou cyclique s’accompagne d’une modification significative du tonus basal de la bronche avec deux étapes : l’une précoce apparaît au cours de l’exposition même des variations de tension pariétale, l’autre est tardive et apparaît à l’arrêt de l’étirement. Concernant l’étape précoce, elle se révèle robuste car aucun pré-traitement et particulièrement l’abrasion de l’épithélium ne la supprime totalement. La caractérisation de cette réponse implique notamment la voie des NO synthases et des Rho-A kinase. La réponse tardive fait quant à elle intervenir l’épithélium ainsi que la voie des NO-synthase suggérant un rôle prépondérant du NO. Par contre, ces modifications de force au repos sont indépendantes de la sécrétion de médiateurs inflammatoires détectés par ELISA. L’approche génétique renforce par contre le rôle du tissu de soutien bronchique en activant la synthèse de collagène (MMP-9). Au total l'application d'une contrainte cyclique renforce la bronchoconstriction par inhibition de la voie des NOsynthases et de la mécanotransduction. / The tracheo-bronchial tree is a true immunologic sentinel related to the huge interface with the external environment. Moreover, it is submitted to variable physical strains (tidal ventilation and variation in pressure) and an excessive response leads to the genesis of some pathology as hyperresponsiveness. The aim of this work on an isolated organ model was to characterize the human bronchial response to a single or repetitive and physiological stretch as observed during mechanical ventilation. From a functional perspective, a single strain or a cyclic stretch significantly increased the basal tone of the human bronchus with a two-step response: the early response appears during cycling and the delayed after the stretch has ceased. The early response is robust then no pre-treatment and especially epithelial removal totally inhibits it. This response implies NO synthase and Rho-A kinase pathway with a reduction of the developed basal tone with these inhibitors. As it concerns the late response, it involved epithelium and NO synthase suggesting a prominent action of NO. Inflammatory mediators are not directly involved in the rise of basal tone because stretch-induced secretion as detected with ELISA is very low. Genomic approach transiently activates transcription of genes for MMP-9, involved in the collagen production and consequently in the support tissue of the bronchial tree. As a conclusion, cyclic stretch enhances bronchoconstriction by inhibition of the NO-synthase pathway and mechanotransduction.

During the last decade medical applications of textile sensors have been growing rapidly and textile sensors are the focal research point for many sensor projects. Textile sensors are still not available as a mainstream product to replace conventional electric sensors and electrodes. Textile sensors can be integrated in a textile garment to measure vital signs of a human being. In this regard stretch sensors are able to measure breathing rate of a person. In this project we use seamless knitting technique to make stretch sensors using conductive fibers. The resistance difference between stretching and relaxing of these sensors gives a pattern for human breathing. Four knitting structures with different conductive fibers are made and tested with cyclic tester to construct a graph between resistance and time to find the knitting structure which gives the best results. Tests are also done to check the results after washing. These sensors can be used in breathing monitoring of patients during daily life. / Program: Master Programme in Textile Technology

During the last decade medical applications of textile sensors have been growing rapidly and textile sensors are the focal research point for many sensor projects. Textile sensors are still not available as a mainstream product to replace conventional electric sensors and electrodes. Textile sensors can be integrated in a textile garment to measure vital signs of a human being. In this regard stretch sensors are able to measure breathing rate of a person. In this project we use seamless knitting technique to make stretch sensors using conductive fibers. The resistance difference between stretching and relaxing of these sensors gives a pattern for human breathing. Four knitting structures with different conductive fibers are made and tested with cyclic tester to construct a graph between resistance and time to find the knitting structure which gives the best results. Tests are also done to check the results after washing. These sensors can be used in breathing monitoring of patients during daily life. / Program: Master programme in Textile Technology

A redução eletroquímica de 3,3\'-(1,3- e 1,4-fenileno)-bis-(2-propenoatos de etila), sistemas diolefínicos cujas duplas ligações estão separadas por um anel benzênico, foi investigada em N,N-dimetilformamida (DMF) e acetonitrila (MeCN) e metanol/acetonitrila (MeOH/MeCN) (7:3) (v/v). As eletrólises a potencial controlado em DMF e MeCN conduziram a hidrodímeros cíclicos derivados da ciclopentanona com elevada estereosseletividade, análogos aos produtos formados a partir de ésteres do ácido cinâmico nas mesmas condições experimentais. Ao lado dos hidrodímeros, quantidades variáveis de produtos de polimerização e de hidrogenação das duplas ligações dos grupos etoxicarbonilvinila eram formados. Foram examinados a influência do pH, concentração inicial dos substratos e presença de doadores de prótons (MeOH/MeCN) sobre o curso da redução eletroquímica. A maior complexidade dos produtos de eletrólise no substrato 1,4-substituído quando comparada as produtos do 1,3-substituído pode ser explicada, em parte, pela maior interação eletrônica dos grupos etoxicarbonilvinila através do anel aromático no primeiro. / The electrochemical reduction of ethyl 3,3\' -(1,3 and 1,4-phenylene)-bis-(2-propenoates), diolefinic systems whose double bonds are separated by a benzene ring, was investigated in N,N-dimethylformamide (DMF), acetonitrile (MeCN) and methanol/acetonitrile (MeOH/MeCN) (7:3) (v/v). Controlled potential electrolyses in DMF and MeCN afforded cyclic hydrodimers derivatives of cyclopentanone with high stereoselectivity as are the products formed from cinnamic acid esters under similar experimental conditions. Besides the hydrodimers variable amounts of polymerization and side chain carbon-carbon double bond hydrogenation products were formed. The influence of pH, initial concentration of substrates and the presence of proton donors (MeOH/MeCN) upon the electrochemical reduction was examined. The formation of more complex reaction mixtures in the case of the 1,4-substituted substrate when compared with the 1,3-substituted may be explained, at the least partially, due to a larger electronic interaction between the ethoxycarbonylvinyl groups through the aromatic ring in former.

Made available in DSpace on 2014-06-11T19:22:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-28Bitstream added on 2014-06-13T18:08:00Z : No. of bitstreams: 1 oliveira_el_me_sjrp.pdf: 531004 bytes, checksum: 26290057a6f49446476e6e8192925843 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho, descrevemos cíclicas de reticulados algébricos Zn-rotacionados de dimensão ímpar. Essas construções são obtidas através da imersão Rn, via homomorfismo canônico, de determinados Z-módulos livres de posto finito contidos em subcorpos de extensões ciclotômicas do tipo Q(ζp), Q(ζp2), Q(ζpq)e Q(ζpq2), com p e q primos ímpares. Caracterizamos os reticulados e apresentamos propriedades e aplicações na Teoria da Informação. / In this work we describe cyclic constructions of odd dimension. These constructions are obtained by immersion in Rn via the canonical homomorphism, of certain Z-free modules of finite rank contained in subfield cyclotomic extensions of type Q(ζp), Q(ζp2), Q(ζpq)e Q(ζpq2), com p e q odd prime. Featuring the obtained lattices and presenting properties and applications in Information Theory.

This Thesis describes the activity and mechanism of alkaline earth organohydroborate, tetrahydroborate and alkoxide catalysts for the ring-opening polymerisation (ROP) of cyclic esters including rac-, L-, D- and meso-lactide (LA), and rac-β-butyrolactone (rac-BBL). <b>Chapter One</b> introduces cyclic esters and general mechanisms for their ROP to give polyesters. Living and immortal ROP, an overview of stereocontrolled ROP, and determination of polylactide (PLA) stereosequences are given. Various techniques for polymer characterisations are also described. <b>Chapter Two</b> describes the activity and mechanism of heavy alkaline earth organohydroborate complexes for the ROP of LA. The synthesis and characterisation of alkaline earth alkoxide complexes serving as model species are also described, together with their activities for the ROP of LA. <b>Chapter Three</b> describes the activity and mechanism of a cyclic organohydroborate calcium complex for the ROP of LA. The role of borinic esters as chain transfer agents in the ROP of rac-LA is also discussed. <b>Chapter Four</b> describes the activity and mechanism of heavy alkaline earth tetrahydroborate complexes for the ROP of LA. The immortal ROP of rac-LA using heavy alkaline earth alkoxide complexes and borate esters as chain transfer agents is discussed. <b>Chapter Five</b> describes the activity and mechanism of alkaline earth organohydroborate, tetrahydroborate and alkoxide complexes for the ROP of rac-BBL. <b>Chapter Six</b> presents experimental procedures and characterising data for new complexes reported.

Prof. Dr. Rodrigo Luiz Oliveira Rodrigues Cunha / Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Ciência & Tecnologia - Química, 2014. / O presente trabalho consiste na síntese dos fragmentos C1-C4 e C5-C9 do ácido (2S,4E,6R,8S)-8-hidróxi-2,4,6-trimetil-non-4-enóico (1) que corresponde à porção policetídica da Jaspamida e de diversos Geodiamolídeos. A metodologia empregada para a obtenção de tais fragmentos é raramente vista, pois os dois enantiomêros do precursor; o (RS)-2-metil levulinato de metila; são utilizados na síntese de uma mesma molécula. O fragmento C1-C4 foi obtido através de uma resolução cinética enzimática, promovida por lipase de pâncreas de porco com auxílio da adição de Na2SO4 1,6 mol.L-1 baseando-se na série de Hofmeister para elevar o excesso enantiomérico do produto e finalmente através de uma reação de reciclo fornecer o ácido (-)-(S)-2-metil-4-oxopentanóico com excesso enantiomérico >99%. O fragmento C5-C9 foi obtido através redução do enantiômero não hidrolisado, o (R)-2-metil-4-oxopentanoato de metila, originando o (4R,4S)-2-metil-pentan-1,4-diol, que teve seu álcool secundário resolvido através de uma reação de resolução cinética enzimática com o emprego de lipase de Candida antarctica B. / The present work consists in the preparation of fragments C1-C4 and C5-C9 of (2S,4E,6R,8S)-2,4,6-trimethyl-8-hydroxy-non-4-enoic acid (1), that corresponds to polyketide unit of Jaspamide and Geodiamolides. The methodology applied to obtain such fragments is rarely seen, once both fragments of precursor, (RS)-methyl 2-methyl levulinate are used in the synthesis of the same molecule. The fragment C1-C4 was obtained through an enzymatic kinetic resolution promoted by Porcine Pancreas Lipase with assistance of addition of NaSO4 1.6 mol.L-1 based on Hofmeister series to increase the enantiomeric excess of product and finally through a recycle reaction resulting the (-)-(S)-2-methyl-4-oxopentanoic acid with enantiomeric excess >99%, the fragment C1-C4. The fragment C5-C9 was obtained through a reduction of the enantiomer not hydrolyzed, (R)-methyl-2-metil-4-oxopentanoate, affording a diastereomeric mixture of (2R)-methylpentan-1,4-diol, that had the secondary alcohol resolved through a reaction of kinetic enzymatic resolution with employment of Candida antarctica lipase B.

Einleitung: / Introduction:

Les travaux présentés concernent le développement d'un modèle de prévision de durée de vie unifié pour traiter les problématiques de fatigue à faible et grand nombre de cycles. Le modèle est basé sur une approche à deux échelles et un endommagement de type Lemaitre. Le caractère "en vitesse" de la loi d'endommagement permet de traiter des chargements complexes, non proportionnels et aléatoires. Une campagne expérimentale de fatigue sur 12 éprouvettes cruciformes en alliage TA6V pour application aérospatiale est présentée. Elle comporte des essais biaxiaux proportionnels et non proportionnels ainsi que des cas de chargement pseudo-aléatoires. L'utilisation de la corrélation d'images numériques prises dans la zone utile permet d'évaluer les déformations locales en réponse aux sollicitations appliquées. Les cas de chargements sont simulés afin de confronter les déformations de surface et les durées de vie obtenues par calcul, aux résultats expérimentaux. Parmi les contributions théoriques présentées dans le manuscrit, sont à noter : - La proposition d'une nouvelle loi d'évolution pour écrouissage cinématique adaptée au comportement élastoplastique du TA6V sous chargement cyclique; - L'utilisation d'une correction élastoplastique locale permettant d'évaluer les déformations plastiques en surface à partir de calculs de structures linéaires; - L'amélioration d'un critère de micro-plasticité pour la prise en compte des effets de contrainte moyenne et de triaxialité en fatigue à grand nombre de cycles; - L'unification de deux lois d'endommagement afin d'étendre le domaine de validité du modèle initial vers les durées de vie à faible nombre de cycles. La démarche s'appuyant sur le cadre thermodynamique de la mécanique des milieux continus, de nombreuses perspectives d'amélioration du modèle sont discutées. / This work presents the proposal of a unifying predictive model to deal with LCF and HCF problems. It is based on a two-scale approach initially developed by Lemaitre. As the damage evolution law is rate written, complexity due to non proportional and random loadings may also be treated. An experimental fatigue campaign of 12 cross shaped samples made of TA6V alloy for aerospace applications is presented. It includes not only proportional and non proportional biaxial tests but also pseudo random loadings. Digital Image Correlation is used to evaluate the local strains from pictures taken in the zone of interest. Loadings are the simulated and both strains and lifetimes are compared to experimental observations. Among the theoretical contributions presented in this work, the main are: - A new kinematic hardening evolution law for the modeling of elasto-plasticity of TA6V alloy under cyclic loadings; - Use of local elastoplastic correction from linear Finite Element Calculation to estimate plastic strains in the structure zone of interests; - Improvements of the micro-plastic yield function to take into account mean stress effect and triaxiality effects in the lifetime prediction in HCF domain; - A unifying method of two damage variables in order to extend the validity domain of the initial model to shorter lifetimes (LCF). As the model is based on a thermodunamical framework for continuum mechanics, several extension are mentioned as future propects.

Le milieu marin représente une source d'inspiration pour les chimistes, grâce à l'incroyable diversité structurale des composés isolés des organismes et micro-organismes marins. Parmi eux, la laxaphycine B, un lipopeptide cyclique isolée de la cyanobactérie Anabaena torulosa est comme la plupart des peptides marins produit selon une voie de biosynthèse non ribosomale « NRPS /PKS » et présente une forte activité cytotoxique sur différentes lignées cellulaires cancéreuses. Une des problématiques de ce lipopeptide est l'absence d'information sur son mécanisme d'action. Afin d'identifier des cibles potentielles, mais surtout d'entreprendre des études des relations structure-activités, la confirmation de sa structure est nécessaire. C'est dans cette optique que nous avons entrepris la synthèse de la laxaphycine B en synthèse peptidique en phase solide (SPPS). Dans un premier temps, nous avons entrepris la synthèse des quatre aminoacides non ribosomaux. Dans un second temps, nos efforts se sont concentrés sur le développement d'une stratégie de synthèse pour l'obtention de ce lipopeptide. En dernier lieu, nous avons étudié la structure secondaire possible de la laxaphycine B, afin d'apporter une explication sur son mécanisme d'action. / Marine environment is a source of inspiration for chemists, thanks to the incredible structural diversity isolated from marine organisms and microorganism's compounds. Among them, laxaphycine B, a cyclic lipopeptide isolated from Anabena torulosa cyanobacteria, as like most marine peptides produced by a non-ribosomal biosynthesis pathway "NRPS/PKS”. Furthemore, this peptide has shown a strong cytotoxic activity on various cancer cell lines. One of the problems of this lipopeptide, is the lack of information on its mechanism of action. To identify potential targets and also to study in structure activity relationships, confirmation of its structure is necessary. It is in this context that we undertook laxaphycine B's synthesis using SPPS. In a first step, the four non-ribosomal aminoacids have been synthesized. In a second step, our efforts have focused on the development of a synthesis strategy to obtain laxaphycine B. Lastly, we studied the laxaphycin B's secondary structure to understand its mechanism of action.