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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.
151

InP based tandem solar cells integrated onto Si substrates by heteroepitaxial MOVPE / Cellules solaires tandem à base de InP intégrées sur substrats Si par hétéro-épitaxie MOVPE

Soresi, Stefano 01 October 2018 (has links)
Cette thèse s’intéresse à l'intégration sur Si de cellules solaires III-V à simple et double jonction par épitaxie en phase vapeur aux organo-métalliques (MOVPE). Les dispositifs photovoltaïques ont été réalisés avec des matériaux accordés sur InP. L'objectif était d'abord d'obtenir des dispositifs performants sur des substrats InP, puis de les intégrer sur une structure avec un paramètre de maille différent, en évaluant les effets sur les performances photovoltaïques. Ceci a nécessité la réalisation et l'optimisation de plusieurs étapes de fabrication.Tout d'abord, nous avons réalisé une cellule InP à simple jonction, qui peut correspondre à la cellule top dans notre structure tandem. Cela était également nécessaire pour mettre en place un processus de fabrication pour toutes les cellules suivantes. Les conditions de croissance ont été optimisées en profitant des techniques de caractérisation des matériaux telles que la XRD, l’analyse C-V et le SIMS. En optimisant les épaisseurs et les niveaux de dopage des différentes couches du dispositif, ainsi que le procédé en salle blanche, nous avons obtenu une efficacité de conversion de 12.9%, avec un FF de 84.3%. Nous avons démontré que l'utilisation d'une couche fenêtre en AlInAs au lieu de l’InP peut augmenter l'efficacité à 13.5%, malgré une légère réduction du FF (81.4%). La même procédure a ensuite été étendue à la réalisation d'une cellule solaire InGaAs comme cellule bottom du dispositif tandem. Nous avons obtenu un rendement de 11.4% et un FF de 74.5%.En parallèle, des jonctions tunnels capables de relier électriquement les deux sous-cellules dans un dispositif tandem ont été étudiées. En particulier, nous avons concentré notre attention sur les conditions de croissance de l'anode de la jonction, qui a été fabriquée en AlInAs et dopée avec le précurseur CBr4. Les réactions chimiques d’un tel précurseur avec le précurseur de l’Al et l’In nécessitaient une importante réduction de la température de croissance à 540 °C. En déterminant les effets des flux sur la composition et les niveaux de dopage du composé, nous avons obtenu un dopage élevé de +4x1019 cm-3. En obtenant un niveau équivalent pour la cathode InP:S, nous avons réalisé un dispositif présentant un Jp de 1570 A/cm2, capable de fonctionner dans des conditions de concentration solaire élevée. En combinant finalement les trois dispositifs présentés dans une cellule tandem, nous avons pu obtenir un rendement global de conversion de 18.3%, avec un FF de 83.9%.Un template approprié pour l'intégration III-V/Si a été déterminé en testant plusieurs possibilités fournies par différents partenaires. Les caractérisations XRD et AFM ont démontré qu'un template InP/GaP/Si fourni par la société NAsP était la meilleure option. Ceci a été confirmé par la croissance d'une cellule InP à simple jonction sur le template. La techno sur un substrat Si a été rendu possible en déplaçant le contact arrière de la cellule sur la face avant du dispositif, ce qui a nécessité la mise au point d'un ensemble approprié de masques photolithographiques. La réussite de l’intégration des cellules solaires III-V sur Si a été confirmée par le photocourant produit. Celui-ci correspond à environ 60% de la valeur obtenue sur les substrats InP. De plus, les caractéristiques J-V mesurées donnent une tendance de type diode, démontrant la validité de l'approche proposée. / This thesis focuses on III-V/Si integration of single- and dual-junction solar cells by Metalorganic Vapor Phase Epitaxy (MOVPE). The photovoltaic devices were made with materials lattice matched to InP. The goal was to firstly obtain efficient devices on InP substrates and then to integrate them on a structure with a different lattice parameter, by evaluating the effects on the photovoltaic performances. This required the realization and the optimization of several manufacturing steps.Firstly, we realized an InP single junction device, which may correspond to the top cell of our tandem structure. This was also necessary to set up a manufacturing process for all the next cells. The growth conditions were optimized by taking advantage of material characterization techniques such as XRD, C-V profiling and SIMS. By optimizing thicknesses and doping levels of the various layers of the device, as well as the clean room process, we obtained a conversion efficiency of 12.9%, with a FF of 84.3%. We demonstrated that the use of an AlInAs window layer instead of InP may increase the efficiency to 13.5%, despite a slight reduction in FF (81.4%). The same procedure was then extended to the realization of an InGaAs solar cell as the bottom component of the tandem device. We obtained an efficiency of 11.4% and a FF of 74.5%.In parallel, tunnel junctions able to electrically connect the two subcells in a tandem device were studied. In particular, we focused our attention on the growth conditions of the junction anode, which was made in AlInAs and doped with CBr4 precursor. The particular chemical interactions that such a precursor has with Al precursor and In required a relevant reduction of growth temperature to 540 °C. By determining the effects of the flows on composition and doping levels of the compound, we obtained a high doping of +4x1019 cm-3. By obtaining an equivalent level for the InP:S cathode, we realized a device presenting a Jp of 1570 A/cm2, able to work under high solar concentration conditions. By finally combining the three presented devices in a tandem cell, we could obtain an overall conversion efficiency of 18.3%, with a FF of 83.9%.A proper template for III-V/Si integration was determined by testing several possibilities provided by different partners. XRD and AFM characterizations demonstrated that an InP/GaP/Si template provided by NAsP Company was the best option. This was confirmed by the growth of an InP single junction cell over the template. The processing over a Si substrate was made possible by shifting the rear contact of the cell on the front side of the device, which required the development of a proper set of photolithographic masks. The successful integration of the III-V solar cells on Si was confirmed by the relevant produced photocurrent. This corresponds to around 60% of the value obtained on InP substrates. Furthermore, the measured J-V characteristics show a diode-like trend, which demonstrates the validity of the proposed approach.
152

Associação entre função muscular do quadril e do tronco, equilíbrio e funcionalidade em idosos da comunidade / Association between hip and trunk muscle function, balance and functionality in community-dwelling older adults

Porto, Jaqueline Mello 28 March 2016 (has links)
Estudos pregressos têm investigado causas e fatores de risco para quedas e incapacidade funcional em idosos. Porém, no que se refere a fatores biomecânicos envolvidos no desempenho funcional e controle postural, a contribuição dos grupos musculares proximais de quadril e de tronco ainda recebe pouca atenção. Assim, o objetivo deste estudo foi verificar a associação entre a função muscular dos abdutores e adutores do quadril e dos extensores e flexores do tronco com o desempenho do equilíbrio semi-estático e dinâmico e da funcionalidade de idosos independentes que vivem na comunidade. Métodos: oitenta e um idosos de ambos os sexos foram submetidos à avaliação do equilíbrio e da funcionalidade por meio dos testes: (1) marcha tandem sobre a plataforma de força Balance Master (Neurocom International Inc., Clackamas, OR) para obtenção das variáveis velocidade da marcha tandem e velocidade de oscilação corporal ao final da marcha tandem; e (2) testes clínicos de apoio unipodal e Timed Up and Go (TUG). Também foram submetidos à avaliação da função muscular em dinamômetro isocinético (Biodex System 4 Pro, Nova York, EUA) por meio de 3 contrações isométricas máximas de abdução e adução do quadril e flexão e extensão do tronco para obtenção das variáveis pico de torque (PT) e taxa de desenvolvimento de força (TDF) proporcionais ao peso corporal. Após aplicação do teste de normalidade de Shapiro-Wilk, foi realizado teste de correlação de Pearson (dados com distribuição normal) e de Spearman (dados com distribuição não-normal). Para aquelas variáveis com coeficiente de correlação significativo, foi aplicado teste de regressão linear para quantificar o índice de determinação (r2) da função muscular do quadril e tronco no equilíbrio e funcionalidade de idosos. Foi adotado nível de significância de 5% (p < 0,05). Resultados: houve correlação com índice de determinação significativo do PT dos grupos musculares do quadril e do tronco sobre o desempenho dos testes de equilíbrio e funcionalidade. Em relação à TDF, foi encontrada correlação com índice de determinação significativo da TDF de abdução de quadril e de extensão de tronco sobre a velocidade de oscilação ao final da marcha tandem e sobre o TUG e também da TDF de extensão de tronco sobre o apoio unipodal. Conclusões: esses 10 achados podem ser clinicamente relevantes considerando que (1) diferentes parâmetros da função muscular (como PT e TDF) apresentam diferentes estratégias de intervenção para seu aprimoramento e que (2) problemas de equilíbrio e/ou de funcionalidade em idosos podem estar associados com comprometimentos da TDF e do PT da musculatura proximal, os quais são parâmetros passíveis de intervenção. / Previous studies have investigated causes and risk factors for falls and functional disability in the elderly. However, regarding biomechanical factors involved in the functional performance and postural control, the contribution of the proximal muscle groups of the hip and trunk still receives little attention. The objective of this study was to assess the association between muscle function of hip abductors and adductors and trunk flexors and extensors muscles with the performance of static and dynamic balance and functionality of community-dwelling older adults. Methods: eighty-one elderly of both sexes underwent assessment of balance and functionality through: (1) tandem gait test on the Balance Master force platform (Neurocom International Inc., Clackamas, OR) to obtain the variable tandem gait speed and body sway velocity in the end of tandem gait; and (2) clinical tests of single-leg stance and Timed Up and Go (TUG). The participants also underwent assessment of muscle function in isokinetic dynamometer (Biodex System 4 Pro, New York, USA) through 3 maximal isometric contractions of abduction and adduction of the hip and flexion and extension of the trunk to obtain the variables peak torque (PT) and rate of force development (RFD) in proportion to body weight. The Shapiro-Wilk normality test was performed and then, Pearson correlation test (data with normal distribution) and Spearman (data with non-normal distribution) were applied. Linear regression test was applied to quantify the determination index (r2) of muscle function of the hip and trunk in balance and functionality of the elderly for those variables with significant correlation coefficient. It was adopted a significance level of 5% (p < 0.05). Results: there was correlation with a significant determination index of PT of muscle groups of the hip and trunk in the performance of balance and functionality tests. Regarding the RFD, it was found correlation with significant determination index of RFD of the hip abduction and trunk extension in the body sway velocity in the end of tandem gait and TUG; and of RFD of the trunk extension in single-leg stance. Conclusions: These findings may be clinically relevant considering that (1) different parameters of muscle function (such as PT and RDF) have different intervention strategies for their improvement and (2) problems of balance and / or functionality in the elderly may be 12 associated with impairments of RFD and PT of proximal muscles, which are parameters that can be treated.
153

Cycloisomérisations catalysées par les sels du gallium et les complexes NHC-Gallium(III) / Cycloisomerizations Catalyzed by Gallium Salts and NHC-Gallium(III) Complexes

Tang, Shun 15 November 2013 (has links)
Afin de développer des méthodes alternatives à l'activation de systèmes Pi en catalyse homogène par des métaux nobles coûteux et toxiques, nous nous sommes focalisés sur des complexes métalliques et plus particulièrement ceux de la colonne du group XIII. Cette thèse approche une contribution à ce champ d'études, et nous nous sommes particulièrement concentrés sur la chimie de gallium.Trois principaux aspects ont été étudiés dans ce manuscrit: la réactivité des halogénures de gallium(III), des complexes bien définis de gallium (III) portant carbènes N- hétérocycliques (NHCs), et leur activation de systèmes en catalyse.La thèse est divisée en trois chapitres. Le premier chapitre donne un aperçu des travaux effectués dans le domaine de la synthèse organique faisant intervenir des composés de gallium (III) , en se concentrant sur ​​leur utilisation en tant qu’ acides de Lewis et .Dans le deuxième chapitre, nous avons tenté d'exploiter le potentiel catalytique de GaCl3 dans une nouvelle réaction de cycloisomérisation/Friedel-Crafts en tandem. Une section dédiée à l'étude sur l’hydratation d’alcyne catalysée par GaCl3 est également fournie.Le troisième chapitre commence par une description de la synthèse d'une série de complexes de gallium (III) portant diverses NHCs comme ligands pour surmonter les limites des halogénures de gallium(III) en catalyse. Ensuite, des études de méthodologie sur le processus de tandem impliquant arenynes-1,6 avec les gallium(III) complexes neutres et cationiques ont été décrits. Une évaluation cinétique pour des catalyseurs, des divers substrats et l'influence de contreanions sont discutés. En outre, les efforts dans la version asymétrique de cette tandem transformation et des autres cyclisations sont également présentés.Le dernier chapitre reprend les résultats les plus importants obtenus dans la thèse. Et les orientations futures de la recherche sur l'utilisation des complexes NHC- gallium (III) sont discutées. / Recently, in order to develop alternative activation methods for Pi-systems in homogeneous catalysis instead of employing expensive and toxic noble metal catalysts, first row transition metals and main group metal complexes have attracted great attention. This thesis is a contribution to it, and we focus on gallium chemistry. There are three main aspects dominating this thesis: gallium(III) halides, well-defined gallium(III) complexes bearing N-heterocyclic carbenes (NHCs), and -systems activation in catalysis.The thesis is divided into three chapters. Chapter I provides an overview of the field of organic synthesis involving gallium(III) compounds, focusing on their use as - or -Lewis acids.In Chapter II, we expose our attempts to exploit the catalytic potential of gallium(III) chloride in a novel tandem cycloisomerization/Friedel-Crafts reaction. A section dedicated to the study on GaCl3-catalyzed alkyne hydration is also provided.Chapter III begins with a description of the synthesis of a series of gallium(III) complexes bearing various NHCs as ligands in order to overcome the limitations of gallium(III) halides in catalysis. Next, methodology studies on the tandem process involving 1,6-arenynes with the neutral and cationic gallium(III) complexes are described. The evaluation of scission kinetics for catalysts, substrates variation and influence of counteranions are discussed. In addition, efforts towards the asymmetric version of this tandem transformation and some other cyclizations are also presented.The concluding chapter reiterates the most important results obtained in the body chapters of the thesis. To conclude, the future directions for the research on the use of the NHC-gallium(III) complexes are discussed.
154

Application des réactions de métathèse en synthèse totale : approche synthètique vers les aurisides / Application of metathesis reactions in total synthesis : synthetic approach towards the aurisides

Bourcet, Emmanuel 25 May 2009 (has links)
Les réactions de métathèse sont des méthodes performantes pour la création de doubles liaisons carbone-carbone et leurs popularités s’expliquent par l’accessibilité des catalyseurs nécessaires à celles-ci et par la facilité de mise en oeuvre de ces réactions. Elles ont par ailleurs trouvé de nombreuses applications dans la synthèse de molécules naturelles.Les aurisides A et B sont des molécules naturelles d’origine marine isolées du lièvre des mers Dolabella Auricularia en 1996. Ces macrolides présentent une activité cytotoxique intéressante contre des lignées de cellules cancéreuses HeLaS3 avec des valeurs d’IC50 de 0,17 et 1,2 μg/mLrespectivement.Nous avons dans un premier temps développé une voie d’accès au fragment C1-C9 des composés naturels en se basant sur la réaction de métathèse croisée des oléfines. Une étude sur le mode formation de la structure macrocylique par un processus séquentiel impliquant une réaction demétathèse cyclisante et une cétalisation transannulaire a ensuite été conduite sur des composés modèles permettant l’obtention de macrolactones analogues. Cette méthodologie a ensuite été appliquée à la synthèse stéréocontrôlée du squelette carboné des aurisides seulement dépourvu de sa chaîne latérale attaché sur l’atome de carbone C13.Enfin la réaction de métathèse croisée a également été exploitée dans un processus tandem avec celle d’hydrogénation pour la synthèse énantiosélective du 6-hydroxydodécanoate de pentadécyle,composant principal de l’huile essentiel Ylang-Ylang, et qui est également utilisé en médecine traditionnelle contre le choléra. / Metatheses are very useful synthetic tool for the formation of carbon-carbon bonds and their popularityis due to the facile access of the required catalyst for those reactions and also to the ease to performthem. So far, these reactions have found many for the total synthesis of natural products.The aurisides A and B are natural products and have been isolated from the sea hare Dolabella Auricularia in 1996. These macrolides have shown significant cytotoxicity with IC50 values againstHeLaS3 cervical cancer cells of 0.17 and 1.2 μg/mL respectively.We have first developed an access to the C1-C9 fragment of these compounds using the crossmetathesis reaction as a key step. A study for the formation of the macrocyclic core of the aurisides,using a sequential ring closing metathesis / transannular ketalization process was then developed. Thismethodology was first performed on unfonctionnalized substrates and allowed the synthesis ofmacrolactone analogs. It was then further applied on a stereocontrolled synthesis of the aurisideswithout the side chain attached on carbon C13.Finally, the cross metathesis reaction was also combined in a tandem process with a hydrogenation reaction for the enantioselective synthesis of pentadecyl-6-hydroxydodecanoate, the major componentof essantial oil Ylang-Ylang, and is also used in traditional medical treatment against cholera.
155

Application des processus de métathèse à la synthèse de produits naturels marins / Application of the metathesis reaction to the synthesis of marine natural products

Cros, Fanny 09 July 2010 (has links)
La réaction de métathèse a connu un essor considérable au cours de ces dernières années et le prix Nobel décerné aux chimistes Yves Chauvin, Robert H. Grubbs et Richard R.Schrock est venu récompenser ce travail. Cette réaction a été impliquée pour la synthèse de molécules naturelles d’origine marine. Les thiocyanatines A et B isolées en 2001 ont été ainsi préparées en utilisant la réaction de métathèse croisée. Il s’agit du premier exemple de métathèse en présence de groupements thiocyanates. De plus, ces deux synthèses utilisent la technologie micro-ondes. Le largazole, isolé en 2008, est une cible synthétique très important du fait de son activité anticancéreuse. Ce manuscrit retrace la synthèse d’une partie de cette molécule mais également une étude méthodologique pour la formation de motifs thiazoles par micro-ondes. Enfin, la rugulactone, isolée en 2009, a été préparée selon une stratégie tandem de métathèse cyclisante / métathèse croisée et cette dernière a été appliquée à la synthèse d’analogues. / The metathesis realized an important development during the last few years and the Nobelprize given to the chemists Yves Chauvin, Robert H. Grubbs et Richard R. Schrock came toreward this work. This reaction has been involved for the synthesis of natural molecules of marine origin. Thiocyanatines A and B, isolated in 2001, have been so prepared by using the reaction of cross metathesis. This is the first example of metathesis with the presence ofthiocyanates groups. Moreover, these two syntheses are using the microwave technology. Largazole, isolated in 2008, is a very important synthetic target because of its anticancerous activity. This manuscript is explaining the synthesis of one part of this molecule but it also provides a methodological study for the formation of thiazoles motives by microwave. Then,Rugulactone, isolated in 2009, has been prepared with a tandem strategy of ring clossing metathesis / cross metathesis and this one has been applied to the synthetis of analogues.
156

Einfluss präanalytischer Faktoren auf die Untersuchung des Aminosäure- und Acylcarnitinstoffwechsels

Brauer, Romy 30 July 2012 (has links) (PDF)
Quantitative Untersuchungen krankheitsspezifischer oder krankheitsassoziierter metabolischer Signaturen in humanen Körperflüssigkeiten („Clinical Metabolomics“) haben zum Ziel neue Ansätze für diagnostische oder therapeutische Konzepte zu entwickeln. Die simultane quantitative Analytik von Aminosäuren (AS) und Acylcarnitinen (AC) mittels Tandem-Massenspektrometrie (MS/MS) ermöglicht die Erfassung wichtiger Stoffwechselwege des humanen Metabolismus. Hierzu zählen der Stoffwechsel der ketogenen AS, des Harnstoffzyklus oder der β-Oxidation langkettiger Fettsäuren. Allerdings wird die Konzentration der verschiedenen metabolischen Parameter in humanen Körperflüssigkeiten durch eine Vielzahl präanalytischer in vitro Störfaktoren und in vivo Einflussgrößen beeinflusst. Diese können zu signifikanten Veränderungen der Laborergebnisse führen. Im Rahmen meiner Promotionsarbeit wurden in vitro Störfaktoren (Probenmaterial, Lagerung u. a.) und in vivo Einflussgrößen (Ernährung, physische Aktivität) untersucht und ein standardisiertes Präanalytik-Protokoll entwickelt. Dazu wurden pro Probe 3 µL Trockenblut (TB), 10 µL Serum oder Plasma nach Butylierung mittels Elektrospray-Ionisations-MS/MS analysiert und jeweils 26 AS und 35 AC in 1,5 Minuten simultan bestimmt. Als Ergebnis der zahlreichen systematischen Präanalytik-Untersuchungen konnten signifikante Konzentrationsunterschiede der Metabolite zwischen kapillärer und venöser Blutentnahme sowie in Abhängigkeit des Hämatokrits gefunden werden. Im Vergleich zu Serum und antikoaguliertem Plasma (EDTA, Citrat, Heparin) waren die Konzentrationen der langkettigen AC im TB 5-fach höher. Nahrungsaufnahme und körperliche Aktivität führten ebenfalls zu signifikanten Veränderungen der AS- und AC-Konzentrationen. Durch Optimierung des Probenaufarbeitungsprotokolls konnte die Variabilität zwischen den Messtagen für 17 AS und 6 AC auf < 20 % gesenkt werden. Die Ergebnisse meiner Promotionsarbeit unterstreichen den Einfluss präanalytischer Faktoren auf die Metabolomanalytik. Durch Etablierung und Einhaltung standardisierter präanalytischer Protokolle kann die präanalytische Varianz der Ergebnisse deutlich verringert werden. Sie stellen somit eine wichtige Voraussetzung für eine qualitativ hochwertige Metabolomanalytik im Rahmen klinischer Studien zur Identifizierung neuer Biomarker dar.
157

Propulsion Unit of a 3DOF Helicopter

Ling, Gustav, Persson, Jesper January 2015 (has links)
This Bachelor thesis is a part of a bachelor project which includes building, programming and controlling a 3DOF tandem helicopter. This particular report deals with the propulsion units, i.e. the motors and propellers of the helicopter. It covers the process of how to determine the most suitable propulsion units for the rig that eventually will enable it to run. To achieve this, different data have been processed. Torque and thrust are two important parameters that have been studied. The data have been acquired by different tests, e.g. thrust measurements from a thrust rig. Also more complex analysis such as Blade Element Theory and Actuator Disk Theory have been carried out in order to determine the behaviour of the propulsion units. Study data sheets and databases was also a part of the work. The result of this work was two equal propulsion units which were mounted in the helicopter. They proved to work satisfactory and provided wanted dynamics to the system. / Design & Implementation of a 3DOF Helicopter
158

Développement d'une nouvelle méthodologie d'oléfination catalysée par les complexes de cuivre : applications dans des réactions en tandem

Davi, Michaël January 2008 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal
159

Distribution and evolution of short sequence tandem repeats in eukariotic genomes

Ledda, Alice 06 May 2011 (has links)
Els microsat el lits s on seq u encies d'ADN formades per repeticions en t andem de motius curts. Les curtes seq u encies repetides en t andem s on ubiq ues en els genomes dels eucariotes, tant en les regions codi cants com en les regions no codi cants. Aquestes seq u encies tenen un nivell molt elevat de polimor sme i de diverg encia interespec ca. Hem investigat si les dades obtingudes mitjan cant la seq uenciaci o de nova generaci o del Projecte Pilot dels 1000 Genomes s on utils per quanti car la variabilitat dels microsat el lits en les poblacions humanes i per descobrir nous loci hipot eticament implicats en malalties causades per l'expansi o de repeticions de trinucle otids. Hem analitzat la conservaci o ologen etica dels microsat el lits per entendre el rol que juga la selecci o en l'evoluci o dels microsat el lits. El primer estudi conclou que en els llinatges dels vertebrats, les repeticions en t andem d'amino acids estan m es conservades que altres seq u encies similars localitzades a les regions no codi cants. Aix o ens porta a concloure que l'evoluci o ha mantingut les repeticions a les regions codi cants de les prote nes. En una segona fase hem analitzat la conservaci o dels microsat el lits en diferents regions gen omiques, comparant-les amb la conservaci o dels microsat el lits a les regions interg eniques. Concloem que la selecci o no mant e nom es els microsat el lits als exons, sin o que tamb e a altres regions gen omiques. / Microsatellites are DNA sequences formed by tandem repetition of short motifs. Short sequence tandem repeats are ubiquitous in eukaryotic genomes both in coding and non-coding regions. They show a very high level of polymophism and interspeci c divergence. We investigated the use of next generation sequencing data, from the 1000 Genomes Pilot Prjects, to quantify microsatellite variability in the human population and discover putative new loci involved in trinucleotide repeat expansion diseases. We analysed microsatellites phylogenetic conservation to learn about the role of selection in shaping microsatellite evolution. The rst study con- cluded that in vertebrate lineages amino acid tandem repeats were more conserved than similar sequences located in non-coding regions. This lead us to the conclusion that evolution was preserving repeats in protein-coding regions. In a second stage we analzed the conservation of microsatellites in di erent genomic regions, comparing them with the of microsatellite in inter- genic region. We concluded that selection was not preserving microsatellites only in exons but also in other genomic regions. 1
160

Associação entre função muscular do quadril e do tronco, equilíbrio e funcionalidade em idosos da comunidade / Association between hip and trunk muscle function, balance and functionality in community-dwelling older adults

Jaqueline Mello Porto 28 March 2016 (has links)
Estudos pregressos têm investigado causas e fatores de risco para quedas e incapacidade funcional em idosos. Porém, no que se refere a fatores biomecânicos envolvidos no desempenho funcional e controle postural, a contribuição dos grupos musculares proximais de quadril e de tronco ainda recebe pouca atenção. Assim, o objetivo deste estudo foi verificar a associação entre a função muscular dos abdutores e adutores do quadril e dos extensores e flexores do tronco com o desempenho do equilíbrio semi-estático e dinâmico e da funcionalidade de idosos independentes que vivem na comunidade. Métodos: oitenta e um idosos de ambos os sexos foram submetidos à avaliação do equilíbrio e da funcionalidade por meio dos testes: (1) marcha tandem sobre a plataforma de força Balance Master (Neurocom International Inc., Clackamas, OR) para obtenção das variáveis velocidade da marcha tandem e velocidade de oscilação corporal ao final da marcha tandem; e (2) testes clínicos de apoio unipodal e Timed Up and Go (TUG). Também foram submetidos à avaliação da função muscular em dinamômetro isocinético (Biodex System 4 Pro, Nova York, EUA) por meio de 3 contrações isométricas máximas de abdução e adução do quadril e flexão e extensão do tronco para obtenção das variáveis pico de torque (PT) e taxa de desenvolvimento de força (TDF) proporcionais ao peso corporal. Após aplicação do teste de normalidade de Shapiro-Wilk, foi realizado teste de correlação de Pearson (dados com distribuição normal) e de Spearman (dados com distribuição não-normal). Para aquelas variáveis com coeficiente de correlação significativo, foi aplicado teste de regressão linear para quantificar o índice de determinação (r2) da função muscular do quadril e tronco no equilíbrio e funcionalidade de idosos. Foi adotado nível de significância de 5% (p < 0,05). Resultados: houve correlação com índice de determinação significativo do PT dos grupos musculares do quadril e do tronco sobre o desempenho dos testes de equilíbrio e funcionalidade. Em relação à TDF, foi encontrada correlação com índice de determinação significativo da TDF de abdução de quadril e de extensão de tronco sobre a velocidade de oscilação ao final da marcha tandem e sobre o TUG e também da TDF de extensão de tronco sobre o apoio unipodal. Conclusões: esses 10 achados podem ser clinicamente relevantes considerando que (1) diferentes parâmetros da função muscular (como PT e TDF) apresentam diferentes estratégias de intervenção para seu aprimoramento e que (2) problemas de equilíbrio e/ou de funcionalidade em idosos podem estar associados com comprometimentos da TDF e do PT da musculatura proximal, os quais são parâmetros passíveis de intervenção. / Previous studies have investigated causes and risk factors for falls and functional disability in the elderly. However, regarding biomechanical factors involved in the functional performance and postural control, the contribution of the proximal muscle groups of the hip and trunk still receives little attention. The objective of this study was to assess the association between muscle function of hip abductors and adductors and trunk flexors and extensors muscles with the performance of static and dynamic balance and functionality of community-dwelling older adults. Methods: eighty-one elderly of both sexes underwent assessment of balance and functionality through: (1) tandem gait test on the Balance Master force platform (Neurocom International Inc., Clackamas, OR) to obtain the variable tandem gait speed and body sway velocity in the end of tandem gait; and (2) clinical tests of single-leg stance and Timed Up and Go (TUG). The participants also underwent assessment of muscle function in isokinetic dynamometer (Biodex System 4 Pro, New York, USA) through 3 maximal isometric contractions of abduction and adduction of the hip and flexion and extension of the trunk to obtain the variables peak torque (PT) and rate of force development (RFD) in proportion to body weight. The Shapiro-Wilk normality test was performed and then, Pearson correlation test (data with normal distribution) and Spearman (data with non-normal distribution) were applied. Linear regression test was applied to quantify the determination index (r2) of muscle function of the hip and trunk in balance and functionality of the elderly for those variables with significant correlation coefficient. It was adopted a significance level of 5% (p < 0.05). Results: there was correlation with a significant determination index of PT of muscle groups of the hip and trunk in the performance of balance and functionality tests. Regarding the RFD, it was found correlation with significant determination index of RFD of the hip abduction and trunk extension in the body sway velocity in the end of tandem gait and TUG; and of RFD of the trunk extension in single-leg stance. Conclusions: These findings may be clinically relevant considering that (1) different parameters of muscle function (such as PT and RDF) have different intervention strategies for their improvement and (2) problems of balance and / or functionality in the elderly may be 12 associated with impairments of RFD and PT of proximal muscles, which are parameters that can be treated.

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