INTRODUÇÃO: Avaliação da função diastólica de pacientes portadores de estenose ou insuficiência aórtica submetidos à troca valvar. OBJETIVOS: Avaliação da função diastólica através da análise do NTpró-BNP como método não invasivo para caracterização da insuficiência cardíaca diastólica, comparando com os dados ecocardiográficos através do Doppler Pulsado em Fluxo Mitral, Doppler Pulsado em Veias Pulmonares e Doppler Tecidual em portadores de IAO e EAO. MÉTODOS: Foram avaliados 63 pacientes, 32 pacientes com IAO (25 pacientes do sexo masculino e 7 do sexo feminino), 31 pacientes com EAO (11 pacientes do sexo masculino e 20 pacientes do sexo feminino). As variáveis foram comparadas na média entre os pacientes portador de IAO e EAO no pré e pós-operatório. RESULTADOS: A idade dos pacientes variou de 21 a 81 com média de 55 anos. Observa-se diferença quanto à média de idades entre as diferentes patologias (t-Student p< 0,0001). Os pacientes com IAO apresentam uma média de idade igual a 45,7±14,3 com variação entre 21 e 79 anos e os pacientes com EAO apresentam uma média de idade igual a 61,5±14,7 com variação entre 21 e 81 anos. Na IAO em relação à disfunção diastólica tivemos os seguintes dados com significância estatística do pré para o pós-operatório (6 meses): TRIV (p=0,0011), diferença entre Tempo de onda A mitral e onda A pulmonar (p=0,0097), Vol. Sistólico de AE (p=0,0019), Vol Sistólico de AE Indexado (0,0011), Vol. Diastólico de AE (p=0,0110), DDVE (p<0,0001), DSVE (p<0,0001), VSF (p<0,0001), VDF (p<0,0001), Massa Indexada de VE (p<0,0001) e Relação Volume/Massa do VE (p<0,0001). Na EAO em relação à disfunção diastólica tivemos os seguintes dados com significância estatística do pré para o pós-operatório (6 meses): E/E (p=0,0379), TRIV (p=0,0072), diferença entre o tempo de onda A mitral e tempo de onda A pulmonar (p=0,0176), Vol sistólico de AE(p=0,0242), Vol. Sistólico de AE indexado (p=0,0237), FEdeAE (p=0,0339), DDVE (p=0,0002), DSVE (p=0,0085), VDF (p=0,0194), Massa Indexada de VE (p<0,0001) e Relação Volume/Massa de VE(p<0,0001). O NTpró-BNP se correlacionou positivamente com os diversos graus de disfunção diastólica tanto no pré como pós-operatório CONCLUSÃO: Foram verificados no estudo da função diastólica variação com significância estatística tanto na IAO como na EAO na comparação do pré e o pós-operatório. Da mesma forma notamos variação do NT-proBNP com correlação com as variáveis ecocardiográficas que caracterizam a disfunção diastólica. / INTRODUCTION: Assessment of diastolic function in patients with aortic stenosis or aortic regurgitation waiting for aortic valve replacement. OBJECTIVE: Assesment of diastolic function with Doppler methods:Doppler signals from transvalvar mitral inflow, tissue Doppler imaging (TDI) and Doppler in pulmonary veins(DPV) correlating with serum brain peptide natriuretic (NTproNP) before and 6 months after aortic valve replacement (AVR). METHODS: We have analyzed 63 patients, 32 with AR (25 males and 7 females), 31 AS (11 males and 20 females).The indices were compared with AS and AR before and after AVR. RESULTS: The ages of patients ranged from 21 to 81 mean age was 55 years old.We have seen difference between mean age of AS and AR (t-Student-p<0.0001). Patients with AR have had mean age 45.67 plus/minus 14.28, range 21 to 79 years old and patients with AS have had mean age 61.50 plus/minus 14.72, range 21 to 81 years old. The patients who had AR the indices showed differences: Isovolumetric Relaxation Time IRT(p=0.0011), Diference between the pulmonary A wave duration and mitral A duration (p=0.0097), Left Atrial Systolic Volume (p=0.0019), Left Atrial Systolic Volume Index(p=0.0011), Left Atrial Diastolic Volume (p=0.0110), Left Ventricular Diastolic Diameter (p<0.0001), Left Ventricular Systolic Diameter (p<0.0001), End Systolic Volume (p<0.0001), End Diastolic Volume (p<0.0001), Left Ventricular Mass Index (p<0.0001) and Left Ventricular Volume and Left Ventricular Mass Index ratio (p<0.0001). Analyzing patients with AS the indices who showed differences: (The ratio of mitral velocity to early diastolic velocity of the mitral annulus) E/E (p=0.0379)(Isovolumetric Relaxation Time)(p=0.0072) IRT, Diference between the pulmonary A wave duration and mitral A duration (p=0.0176), Left Atrial Sistolic Volume (p=0.0242), Left Atrial Systolic Volume Index (p=0.0237), Left Atrial Ejection Fraction (p=0.0339) Left Ventricular Diastolic Diameter (p=0.0002), Left Ventricular Systolic Diameter (p=0.0085), End Diastolic Volume (LVEDV) (p=0.0194), Left ventricular Mass Index(p<0.0001), Left Ventricular Volume and Mass Index Ratio (p<0.0001). CONCLUSIONS: As we studied diastolic function we have verified significant statistic variation in aortic regurgitation and aortic stenosis comparing before and after aortic valve replacement. Likewise we have seen there is correlation between NTproBNP and echocardiographic variables that show diastolic dysfunction.

Ce document rassemble les travaux effectués durant mes années de thèse. Je commence par une présentation concise des résultats principaux, puis viennent trois parties relativement indépendantes.Dans la première partie, je considère des problèmes d'inférence statistique sur un échantillon i.i.d. issu d'une loi inconnue à support dénombrable. Le premier chapitre est consacré aux propriétés de concentration du profil de l'échantillon et de la masse manquante. Il s'agit d'un travail commun avec Stéphane Boucheron et Mesrob Ohannessian. Après avoir obtenu des bornes sur les variances, nous établissons des inégalités de concentration de type Bernstein, et exhibons un vaste domaine de lois pour lesquelles le facteur de variance dans ces inégalités est tendu. Le deuxième chapitre présente un travail en cours avec Stéphane Boucheron et Elisabeth Gassiat, concernant le problème de la compression universelle adaptative d'un tel échantillon. Nous établissons des bornes sur la redondance minimax des classes enveloppes, et construisons un code quasi-adaptatif sur la collection des classes définies par une enveloppe à variation régulière. Dans la deuxième partie, je m'intéresse à des marches aléatoires sur des graphes aléatoires à degrés precrits. Je présente d'abord un résultat obtenu avec Justin Salez, établissant le phénomène de cutoff pour la marche sans rebroussement. Sous certaines hypothèses sur les degrés, nous déterminons précisément le temps de mélange, la fenêtre du cutoff, et montrons que le profil de la distance à l'équilibre converge vers la fonction de queue gaussienne. Puis je m'intéresse à la comparaison des temps de mélange de la marche simple et de la marche sans rebroussement. Enfin, la troisième partie est consacrée aux propriétés de concentration de tirages pondérés sans remise et correspond à un travail commun avec Yuval Peres et Justin Salez. / This document presents the problems I have been interested in during my PhD thesis. I begin with a concise presentation of the main results, followed by three relatively independent parts. In the first part, I consider statistical inference problems on an i.i.d. sample from an unknown distribution over a countable alphabet. The first chapter is devoted to the concentration properties of the sample's profile and of the missing mass. This is a joint work with Stéphane Boucheron and Mesrob Ohannessian. After obtaining bounds on variances, we establish Bernstein-type concentration inequalities and exhibit a vast domain of sampling distributions for which the variance factor in these inequalities is tight. The second chapter presents a work in progress with Stéphane Boucheron and Elisabeth Gassiat, on the problem of universal adaptive compression over countable alphabets. We give bounds on the minimax redundancy of envelope classes, and construct a quasi-adaptive code on the collection of classes defined by a regularly varying envelope. In the second part, I consider random walks on random graphs with prescribed degrees. I first present a result obtained with Justin Salez, establishing the cutoff phenomenon for non-backtracking random walks. Under certain degree assumptions, we precisely determine the mixing time, the cutoff window, and show that the profile of the distance to equilibrium converges to the Gaussian tail function. Then I consider the problem of comparing the mixing times of the simple and non-backtracking random walks. The third part is devoted to the concentration properties of weighted sampling without replacement and corresponds to a joint work with Yuval Peres and Justin Salez.

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This diploma thesis serves as a constructional study of an axial pump with a tandem arrangement of impellers. It may also be perceived as proposal of possible constructional variants that could be used as cardiac replacements. The thesis offers several conceptual variants, while the selected ones are elaborated in detail. Drawing documentation and 3D models are included in the attachment. The components were dimensioned according to the parameters necessary for proper heart function.

The main objective of this diploma thesis is to determine the influence of synovial fluid compodition and the influence of surface microtextures on lubrication of hip join replacements. For all experiments, hip joint simulator based on the pendulum principle was utilized. Metal heads (CoCrMo) manufactured by B Braun company and and tailor made acetabular cups from optical glass were used as contact couples. Acetabulum dimensions were fabricated according to dimensions of real implants. Experiments with surface microtextures simulated walking cycle for 210 s and development of lubrication film over time was observed.Results have shown that all types of tested structures improved lubrication of contact area, where the best results were obtained for square and triangle shapes respectively. Second set of experiments was based on the fact, that the composition of synovial fluid of healthy people differs from the composition of patients with various stages of osteoarthritis. Therefore, experiments with different model fluids were compared, which in their composition correspond to different groups of patients. For the model fluid that corresponds to the largest number of cases, experiments with individual components and combinations thereof were subsequently performed to provide a more detailed description of how these components affect the film-forming mechanism. The results show, that a change in fluid composition of patients with osteoarthritis can have a major negative effect on fluid formation process within the pair.

Predložená dizertačná práca sa zaoberá analýzou opotrebenia totálnych bedrových endoprotéz za použitia optických metód. V práci bol predstavený nový prístup hodnotenia objemového úbytku materiálu pomocou 3D optického skeneru. Tento nový prístup je časovo efektívny, poskytuje veľké množstvo snímaných bodov na povrchu implantátu. Množstvo bodov umožňuje presnejšiu rekonštrukciu pôvodnej geometrie a prípadné rekonštrukcie nežiaducich poškodení polyetylénovej vložky pri extrakcii. Predstavené metóda bola validovaná za pomoci štandardizovanej gravimetrickej metódy v súlade s ISO 14242. Následne bol optická skenovacia metóda použitá v troch štúdiách zameraných na analýzu opotrebenia, mechanické zmeny artikulujúceho povrchu a mikroštruktúrne zmeny v dôsledku zlyhania implantátu. Analýza 23 extrahovaných polyetylénových vložiek typ Bicon - plus s rozšíreným použitím v Českej republike poukázala na niektoré problémy spojené so zlyhaním implantátu. Adhezívno - abrazívne opotrebenie bolo identifikované v oblasti penetrácie femurálnej hlavice a následné poškodenia ako delaminácia materiálu , plastické deformácie a pitting boli pozorované v okolí tejto oblasti. Analýza materiálových vlastností poukázala na degradáciu mechanických a chemických vlastností, čo bolo prevažne závislé od rozsahu opotrebenia implantátu. U implantátov boli pozorované výrazné plastické deformácie , nárast oxidačného indexu a nižší pomer tvrdosti voči modulu elasticity, v porovnaní s novými vzorkami. Tečenie materiálu a plastické deformácie, ktoré vykazovali všetky extrahované vzorky boli analyzované v závere predloženej dizertačnej práce, na základe testov na nových implantátoch v zábehovom cykle. Cieľom práce je uviesť nový prístup analýzy opotrebenia polyetylénových vložiek za pomoci optických skenovacích metód a preukázať jeho použiteľnosť na analýze súboru extrahovaných implantátov. Výsledky získané pomocou tejto metódy sa ukázali ako vhodné a môžu viesť k lepšiemu pochopeniu procesov opotrebenia a zlyhávania implantátov.

The thesis is focused on the research on micro-milling with the aim to specify the latest findings and trends in milling and micro-milling. The introduction consists of the specification of micro-milling and its comparison with conventional milling. The main goal of the thesis is to interpret modern trends in micro-milling technology, such as machine modernization, advanced machining strategies and the latest CAD/CAM software. The second part deals with the influence of cutting parameters on the overall workpiece quality. The final part is devoted to the application and use of micro-milling technology.

This diploma thesis deals with palletization of heavy workpieces that are used by multi-purpose machining centers. The final outcome introduces a suitable option for palletization heavy workpieces of multi-purpose machining centers. In the first part of the thesis is draft of machining centers with parameters which were chosen by exploration of market for selecting suitable solution. The second part of thesis is dealing with a detailed draft palletization made by parts of exploration of market then design palletization system and design pallet changer. The designed construction of pallet changer is dimensioned with help of analytical calculating methods and numerical simulations methods. Outcome palletization system allows automatic change of twenty tons workpieces including pallet between two storage places.

This master's thesis deals with stress-strain analysis of hip joint after total hip replacement. These stress-strain states are compared between four variable stems. A research study of available literature is presented with the focus on finite element analysis of hip joints. Basics of hip's joint anatomy is described along with total endoprostheses' variants and properties. Computational modeling was chosen as a solution method using finite element analysis. The solution was executed using ANSYS software. For each stem there was created a computational model which consists of several submodels such as model of geometry, material, contacts and loading. The assesed variables were total hip displacement, contact pressure between the head and liner, stress on each stem and strain on femur. The evaluation of femur's bone tissue was accomplished on basis of Frost's mechanostat in seven Gruen zones.

Syftet med studien har varit att ta reda på vad det är som gör att vissa möbler och inredning finns kvar hos oss en längre tid. Hur designers kan skapa hållbara produkter som konsumenten vill behålla en längre tid. På så sätt förlängs produktens livslängd och bidrar till en hållbarare konsumtion. Teorier som användes i studienvar produktanknytning, produktlivslängd, produktutbyte, tidlös design, estetik, form och material med ett övergripande fokus på hållbar design. Genom teorierna, möbelanalyser, intervjuer, skiss och prototypande har exempel för att designa för en lång livslängd tagits fram. Resultatet av studien blev en färgglad bordslampa med de typiska karaktäristiska dragen av en lampa och samtidigt en unik och skulptural design. / The purpose of the study has been to find out what it is that makes certain furniture and furnishings remain with us for a long time. How designers can create sustainable products that the consumer wants to keep for a longer period of time. In this way, the product lifetime is extended and contributes to more sustainable consumption. Theories used in the study have been product attachment, product longevity, product replacement, timeless design, aesthetics, form and materials with an overall focus on sustainable design. Through the theories and furniture analyzes, interviews, sketches and prototyping, examples for designing for an extended product life have been found. The result of the study was a colorfull table lamp with the typical characteristic features of a lamp and at the same time with a unique and sculptural design.