Le développement scientifique actuel contribue à assurer le confort dans les bâtiments grâce à une grande variété de technologies. Une utilisation rationnelle des ressources énergétiques a un effet bénéfique sur l'économie et la protection de l'environnement. En ce qui concerne l'utilisation de la trigénération, elle devient de plus en plus répandue. La thèse porte sur l'analyse et l'optimisation de schemas hybrides d'alimentation des espaces habitables avec de l’énergie thermique. Pour une analyse cohérente il est nécessaire d'utiliser un outil qui peut égaliser les différents types d'énergie dans le système: chimique, électrique, thermique. L'étude basée sur l'analyse exergétique met en évidence les pertes d'énergie utilisable et les opportunitées de recuperation de l'energie, tout en offrant la possibilité de prendre des décisions fonctionnelles et structurelles pour accroître l'efficacité du système. Les objectifs de cette thèse sont : l'élaboration de différents schémas pour produire simultanément de l’électricité, du froid et de l’eau chaude sanitaire; l’étude et l’optimisation des machines frigorifiques à absorption et à éjection en utilisant l’approche exergétique; l’étude d'un moteur turbo diesel suralimenté; l’étude et l’optimisation du système moteur – machine à froid en utilisant l’analyse exergétique. Deux études de cas ont été développées : bilan thermique d'un bâtiment à rafraîchir, qui a permis d’estimer la puissance frigorifique à installer et bilan global d’un système de cogénération – électricité plus chauffage urbain. / The current scientific development help ensure the comfort in buildings with a large variety of technologies. Rational use of energy resources has a positive effect on the economy and protecting the environment. Concerning the trigeneration, it is becoming more and more widespread. This PhD focuses on the analysis and optimization of hybrid schemes of production and distribution of heat for buildings. For a coherent analysis it is necessary to use a tool that can equalize the different types of energy in the system: chemical, electrical, thermal. The study based on exergy analysis highlights the energy losses and opportunities for the recovery of energy, and provide ability to take functional and structural decisions to increase efficiency.In this thesis, several aspects were examined: the development of a scheme to supply several utilities: electricity, cold and hot water; the study and optimization of absorption and ejection refrigerating machines using exergy analysis; the study of a supercharged turbo diesel engine, the study and optimization of the engine – refrigerating machine system, using exergy analysis.Two case studies were performed: the energy balance of a building, which was used to estimate the cooling capacity to install and the overall performance of a cogeneration - district heating system.

Multiple theoretical frameworks posit that interactions between the autonomic nervous system and higher-order neural networks are crucial for cognitive regulation. However, few studies have directly examined whether autonomic physiology influences brain activity during cognitive tasks, and even fewer of those studies have examined both autonomic branches when doing so. Measures of selective attention derived from event-related brain potentials (ERPs) are particularly well-suited for addressing this question, given that ERP selective attention tasks are designed to control for the influences of psychomotor processes and arousal and are predictive of higher-order cognitive function in children and adults. Such research is particularly promising for understanding how early adversity impacts neurocognitive development in children, given that stress experienced early in life impacts both autonomic function and selective attention. Here, a broad literature review is presented, integrating findings across studies of autonomic physiology, cognition, and brain activity in children and adults (Chapter 1). Then, two experiments are described where cardiac measures of parasympathetic and sympathetic activity were recorded concurrently with ERPs during an auditory selective task in a sample of adults (Chapter 2) and in a sample of preschool-aged children (Chapter 3). Results from both experiments demonstrate a key role for the sympathetic nervous system in selective attention for adults and children, such that greater sympathetic activity is associated with larger effects of selective attention on ERPs. These findings are then reviewed with suggestions for how existing models of neurovisceral integration might be updated to better emphasize the role of sympathetic nervous system activity in neurocognitive processes, emphasizing measures of threat-related and reward-related arousal, as represented by galvanic skin response and pre-ejection period, respectively (Chapter 4). Future directions are also discussed, including recommendations for future studies of neurovisceral integration to examine associations between physiology, behavior, and brain activity at the single-trial level, to incorporate participants from more diverse backgrounds of life experience, and to examine the plasticity of autonomic mechanisms implicated in neurocognitive function.

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Transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) imaging are two commonly used imaging modalities for evaluating the size and function of the heart. There are advantages and disadvantages associated with both modalities when examining the right ventricle (RV). The RV is positioned partly behind the sternum and lung, sometimes causing shadows in the TTE images. This along with the complex shape of the RV makes volume calculations challenging by 2D TTE. CMR is considered to be the reference method for volume calculations of the ventricles. The valve separating the RV from the right atrium is however often oblique compared to the valve separating the left ventricle from the left atrium. This complicates RV volume calculations using conventional CMR short-axis stack images. The aim of this thesis was to find ways to improve the RV stroke volume and ejection fraction calculations using TTE and CMR. A method, transferring the position of the tricuspid plane from RV long-axis images to short-axis images, was developed to improve the separation of the right atrium from the RV when calculating RV stroke volumes by CMR. The method provided calculations of RV stroke volumes with good agreement to reference volumes. Further, the movements contributing to the RV stroke volume was studied aiming to find new ways of calculating RV stroke volumes and ejection fraction by TTE. A model for RV stroke volume and ejection fraction calculations was evaluated showing underestimation of stroke volumes by TTE compared to CMR, which probably depend on differences in distance measurements using the two modalities. The model provided, however, promising results for ejection fraction calculations which was validated in a study of 37 participants that covered a wide range of EF.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22042号 / 医博第4527号 / 新制||医||1039(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 佐藤 俊哉, 教授 湊谷 謙司, 教授 稲垣 暢也 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Author: Bc. Michaela Tejnecká Title: The effect of regularly applied Nordic walking on selected cardiorespiratory parameters in adults after heart valve surgery. Aim: The aim of this work was to analyze the effect of six months of Nordic walking intervention on selected casrdiorespiratory parameters in adults after heart valve surgery. Methods: The study included ten individuals (mean age 62 years) who were at least five years apart after heart valve surgery. Blood pressure (BP) was measured using a pulsed wrist tonometer, blood oxygen saturation (BOS) and heart rate (HR) were measured using a pulse oximeter, and the ejection fraction of the heart (EF) was evaluated echocardiographically. Nordic walking training units took plaxe once a week for 6 months. During this intervention, the level of training gradually increased both in distance and elevation of the terrain. Results: In all probands there was an average reduction in systolic blood pressure during exercise by an average of 10,3 mmHg and a reductionin heart rate during exercise by an average of 24 beats per minute. The resting ejection fraction increased by an average of 5,5% after six month intervention. These changes were statistically significant (p<0,01). The results of the work point to the benefits of Nordic walking for cardiac...

Author: Bc. Michaela Tejnecká Title: The effect of regularly applied Nordic walking on selected cardiorespiratory parameters in adults after heart valve surgery. Aim: The aim of this work was to analyze the effect of six months of Nordic walking intervention on selected casrdiorespiratory parameters in adults after heart valve surgery. Methods: The study included ten individuals (mean age 62 years) who were at least five years apart after heart valve surgery. Blood pressure (BP) was measured using a pulsed wrist tonometer, blood oxygen saturation (BOS) and heart rate (HR) were measured using a pulse oximeter, and the ejection fraction of the heart (EF) was evaluated echocardiographically. Nordic walking training units took plaxe once a week for 6 months. During this intervention, the level of training gradually increased both in distance and elevation of the terrain. Results: In all probands there was an average reduction in systolic blood pressure during exercise by an average of 10,3 mmHg and a reductionin heart rate during exercise by an average of 24 beats per minute. The resting ejection fraction increased by an average of 5,5% after six month intervention. These changes were statistically significant (p<0,01). The results of the work point to the benefits of Nordic walking for cardiac...

京都大学 / 新制・課程博士 / 博士(理学) / 甲第23012号 / 理博第4689号 / 新制||理||1672(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)准教授 野上 大作, 教授 太田 耕司, 教授 一本 潔 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

Diabetes causes cardiomyopathy and increases the risk of heart failure independent of hypertension and coronary heart disease. This condition called “Diabetic Cardiomyopathy” (DCM) is becoming a well- known clinical entity. Recently, there has been substantial research exploring its molecular mechanisms, structural and functional changes, and possible development of therapeutic approaches for the prevention and treatment of DCM. This review summarizes the recent advancements to better understand fundamental molecular abnormalities that promote this cardiomyopathy and novel therapies for future research. Additionally, different diagnostic modalities, up to date screening tests to guide clinicians with early diagnosis and available current treatment options has been outlined.

A left ventricular assist device is a mechanical pump implanted in patients with heart failure that continuously takes blood from the left ventricle and delivers it to the aorta, thus decreasing ventricular load. The device is typically considered as a ‘bridge to transplant’, i.e. as a temporary therapy, and involves several risks. Modified ventricular hemodynamics due to a heart pump implantation is studied in-vitro using an elastic ventricle. The ventricle is incorporated into a pulse duplicator setup, which prescribes realistic pulsatile inflow/outflow to mimic a weak ejection fraction. A continuous axial pump mimics a ventricular assist device and its effect on the ventricular hemodynamics is investigated as a function of the pump flow suction. Using particle image velocimetry, pump flow effectiveness at providing unloading on the ventricle and increasing ejection is observed and understanding if proper recirculation of the myocardium down to the apex is restored under varying flow rate.