Hiperplasia congênita de suprarrenal (CAH) compreende um grupo de transtornos hereditários decorrentes de erros inatos do metabolismo dos esteróides adrenais. O aumento das dimensões das glândulas suprarrenais é um marco morfológico na CAH que pode ser avaliado por métodos de imagem com signifitiva correlação com o controle hormonal dos pacientes. Porém, técnicas de imagem que forneçam informações qualitativas e quantitativas relativas à citoarquitetura das glândulas ainda não foram estabelecidas neste contexto. A difusão por ressonância magnética (DWI) é uma técnica que pode fornecer informações quantitativas dos tecidos através do valor do coeficiente de difusão aparente (ADC). O papel do ADC na avaliação de lesões tumorais adrenais já foi estudado, no entanto, o valor do ADC das glândulas suprarrenais normais ainda não foi descrito. O objetivo geral desta tese foi investigar a utilidade dos métodos de imagem na avaliação da CAH. Os objetivos específicos foram apresentar uma revisão dos métodos por imagem já estabelecidos para avaliação da CAH, validar o cálculo do ADC da glândula suprarrenal e avaliar se o ADC e as dimensões das glândulas suprarrenais poderiam auxiliar no manejo de pacientes com CAH, correlacionando-os com controle hormonal. Esta tese é baseada em artigos, nos quais estão mostrados a metodologia, resultados e discussões relativos a cada uma das etapas. O primeiro artigo, The role of imaging in congenital adrenal hyperplasia, trata de uma revisão sistemática de imagem em CAH, com ênfase em genitografia, ultrassonografia, tomografia computadorizada e ressonância magnética (MRI). O segundo artigo, Apparent Diffusion Coefficient (ADC) of the normal adrenal glands: premilinary results, teve como principal objetivo validar o método de medida do ADC das glândulas suprarrenais. No terceiro artigo, Quantitative magnetic resonance imaging in the evaluation of adrenal glands in children and young adults with congenital adrenal hyperplasia due to 21-hydroxylase deficiency, foram estudados os parâmetros quantitativos por MRI (ADC, volume e medidas lineares) das glândulas suprarrenais que poderiam estar relacionados ao controle hormonal dos pacientes com CAH. Medir o ADC das suprarrenais normais é factível e reprodutível. Em indivíduos saudáveis após a adrenarca o ADC é significativamente menor. Todavia, o ADC não foi capaz de diferenciar indivíduos controles de pacientes com CAH, assim como não apresentou correlação com o status hormonal dos pacientes. O volume e as medidas lineares das glândulas adrenais foram os melhores parâmetros quantitativos por MRI para diferenciar pacientes de indivíduos controles, com correlação positiva com o status hormonal recente dos pacientes com CAH. As dimensões das glândulas suprarrenais avaliadas por MRI podem ser utilizadas como ferramenta auxiliar no acompanhamento dos pacientes e mostrar rapidamente os efeitos da exposição a altos níveis de hormônio adrenocorticotrópico. Apesar de ocorrerem modificações celulares na CAH e de ter sido mostrado neste estudo que em pacientes sem doença hormonal conhecida o ADC é mais baixo após a adrenarca, estas alterações celulares que ocorrem na CAH não foram detectadas pelas medidas de ADC. / Congenital adrenal hyperplasia (CAH) is an autossomic recessive disorder caused by impaired steroidogenesis. A morphological hallmark in CAH is enlarged adrenal glands. Imaging studies have addressed mainly morphological aspects and dimensions of the adrenal glands, which correlate to the patients hormonal statuses. However, no imaging technique was used to evaluate changes in the adrenal glands at a cellular level in these patients. Diffusion-weighted magnetic resonance imaging (DWI) is a magnetic resonance imaging (MRI) technique with the ability to provide quantitative information about intracellular and extracellular space, given by the apparent diffusion coefficient (ADC) values. The role of ADC in evaluation of adrenal lesions has already been studied. However, ADC of the normal adrenals has not yet been described. The main purposes of this study were: to investigate the role of imaging in CAH, to validate the method of calculating ADC values of the normal adrenal glands and to assess hormonal status in patients with CAH and its correlation to quantitative MRI. This is an article-based thesis divided in three articles. The first article, The role of imaging in congenital adrenal hyperplasia, is a systematic review of imaging in congenital adrenal hyperplasia, with emphasis on genitography, ultrasonography, computed tomography and MRI. The article Apparent diffusion coefficient (ADC) of the normal adrenal glands: premilinary results aimed to validate the method of measuring ADC of the adrenal glands. The study of quantitative parameters (ADC, volume and linear measurements) of the adrenals evaluated by MRI that correlate with hormonal status in patients with CAH is described in the third article, Quantitative magnetic resonance imaging in evaluation of the adrenal glands in children and young adults with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Measuring ADC of the normal adrenal glands is feasible and reproducible. In healthy subjects, ADC values were significantly lower after adrenarche. However, neither a difference between ADC values of controls and patients, nor correlations with patients hormonal statuses were found. Volume and linear measurements of the adrenal glands were the best parameter to differentiate patients from controls. Moreover, a positive correlation was found between short-term hormonal control status and adrenal size. Adrenal size assessed by MRI might be a useful tool in the follow-up of patients with CAH. Although adrenal cell structure modifications in patients with CAH have been described, they were not detectable by DWI.

Nous proposons une nouvelle approche pour déterminer le coefficient de diffusion dans des membranes lipidiques se basant sur la formation d'excimères. Alors que les autres modèles statistiques considèrent le système comme un ensemble de points sur un réseau, nous utilisons un modèle à gros grain afin d'étudier des bicouches lipidiques simulées à l'aide du champs de force Martini. Nous déterminons le taux de réaction dépendant du temps à partir des probabilités de survie obtenues a posteriori à l'aide des trajectoires numeriques des bicouches symétriques de DOPC (1,2-Dioleoyl-sn-glycero-3-phosphocholine) et POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) simulées à 283 K et 293 K respectivement. Les dynamiques de collision sont obtenues en distinguant virtuellement les molécules simulées. Les sondes fluorescentes sont supposées semblables aux lipides, et par conséquent, ne modifient pas la dynamique. Nous obtenons une expression générale pour la probabilité de survie en combinant approximation des paires indépendantes et propriétés d'échelle, mais aucune hypothèse n'est faite pour le taux de formation d'excimère. En superposant les intensités d'émission de fluorescence normalisées, déterminées numériquement, aux courbes de titrations expérimentales, nous obtenons deux ensembles de résultats pour le coefficient de diffusion latéral, selon que l'association entre feuillets est autorisée ou pas. Nous utilisons un rayon de capture de 0.5 nm, la distance à partir de laquelle les deux sondes réagissent pour former un excimère. En comparant la dynamique Martini aux expériences de fluorescence, il est possible d'estimer le facteur d'accélération. / We propose a novel approach to extract the lateral diffusion coefficient in lipid bilayers using excimer formation. In contrast to previous statistical models that modeled the system as points undergoing jumps from site to site on a lattice, we use coarse-grained molecular dynamics to study lipid bilayers simulated using the Martini force field. We derive time dependent reaction rates from survival probabilities obtained a posteriori from numerically generated trajectories of symmetric DOPC (1,2-Dioleoyl-sn-glycero-3-phosphocholine) and POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) bilayers at 283K and 293K respectively. Collision dynamics are determined by virtually relabeling the simulated molecules. The fluorescent probes are assumed to behave like ordinary membrane lipids and therefore the dynamics remain unaffected. We derive a generalized expression for the survival probability combining independent pairs and size scaling assumptions, but no assumption is made regarding the kinetic rate of the excimer formation process. By fitting the numerically determined normalized fluorescence emission intensities to experimental titration curves, we obtain two sets of results for the lateral diffusion coefficients depending whether interleaflet excimer association is allowed or not. We use a capture radius of 0.5 nm, the distance at which the probes react to form excimers. By relating Martini dynamics to real fluorescence experiments, we estimate the numerical Martini acceleration factor. We also study mixtures of oxidized-non oxidized DOPC and POPC bilayers using a hydroperoxidized model of these lipids for different concentrations of the oxidized component (3.1%, 25% and 50%). Using pair correlation functions, we extract structural information on the systems and determine whether the two components are prone to mixing or not. Finally, we calculate the thermodynamic mixing parameters within the framework of the virial expansion.

Le nouvel essor industriel du marché des applications mobiles telles que les smartphones ou les tablettes tactiles nécessite de nombreuses recherches afin de concevoir des écrans en verres encore plus résistant. Le procédé d’échange ionique au potassium permet d’améliorer la résistance mécanique des verres grâce à la substitution des ions Na⁺ par des ions K⁺, de plus gros rayon ionique. Elle permet ainsi de bloquer les fissures superficielles du verre et de réduire la casse du matériau. Ce travail est consacré à comprendre le principe de diffusion des ions K⁺ au sein de la structure silicatée de différents verres. Les paramètres, temps, température et composition verrière, influent sur la cinétique de l’échange ionique. Dans les mêmes conditions de trempe, la réduction de la composition à un formateur et à l’ion mobile permet d’améliorer la diffusion et la propagation des ions au sein du matériau. Les conditions de trempe, thermique et temporelle, agissent sur la cinétique de diffusion des ions. Elles réduisent la facilité de déplacement des ions à travers la structure silicaté du matériau avec un changement de comportement au-delà de 8h d’immersion dans les sels fondus. La substitution des Na⁺ par les ions K⁺ et leur différence de taille modifient l’environnement des sites laissés vacants par les ions Na⁺ et modifie la structure silicatée du verre. La spectroscopie IR permet de mettre en évidence les modifications structurales des verres soumis à ce procédé d’échange ionique. Lors de l’introduction des ions K⁺, la structure du verre se dépolymérise et crée des oxygènes non pontants. Ceci permet de montrer que l’échange ionique conduit à l’amélioration du renforcement mécanique des verres. / The new industrial boom of the market for mobile applications such as smartphones or tablets requires much research in order to touch-screens design more resistant. The potassium ion exchange process improves the mechanical strength of glass by Na⁺ ions substitution with K⁺ ions, of larger ionic radius. It thus helps to block surface cracks in glass and reduce breakage of the material. This work is devoted to understand the principle of K⁺ diffusion in the silicate structure of different glasses. The parameters: time, temperature and glass composition affect the kinetic of ion exchange process. In the same quenching conditions, the limitation of the composition just to a former network and a mobile ion can improve the diffusion and the penetration ions inside the material. The quenching conditions, temperature and time, act on the kinetic diffusion. They reduce the mobility of the ions through the structure of the silicate material with a change of behaviour above 8h immersion in molten salts. Substitution of Na⁺ by K⁺ ions having different size affect the environment of the sites left vacant by the Na⁺ ions and modifies the silicate structure of the glass. IR spectroscopy allows highlighting the structural modifications of the glass submitted to this ion exchange process. During the introduction of the K⁺ ions inside the glass, the silicate structure is depolymerized and creates no-bridging oxygens. This allows to demonstrate that the ion exchange lead to the mechanical improvement of the glass.

Une solution prometteuse pour diminuer les émissions anthropogéniques de gaz à effet de serre consiste à injecter une partie des rejets industriels de CO2 dans des formations souterraines. Celles-ci comportent un réservoir entouré de roches de couverture, qui constituent la première barrière à la migration des fluides. La caractérisation de leurs propriétés de confinement et de leur évolution en présence de CO2 est donc un élément clé de la sécurité d’un site de stockage. Le travail présenté propose une méthodologie, appliquée ici à des roches carbonatées du bassin parisien, permettant de mesurer les paramètres de transport de roches de couverture et les conséquences d’un vieillissement en conditions représentatives de celles d’un stockage en aquifère profond. La pression de percée, le coefficient de diffusion des produits de dissolution du CO2, et la perméabilité, paramètres contrôlant les principaux mécanismes de fuite, ont été mesurés avant et après altération des matériaux par réaction avec une saumure saturée en CO2 dans des conditions thermodynamiques typiques d’un réservoir (environ 80°C et 100 bar). Les résultats obtenus ont révélé un bon comportement global des roches, mais également une forte diminution du potentiel de confinement en présence de défauts structurels initiaux (fractures rebouchées, pores de grand diamètre...). Une simulation numérique décrivant les évolutions de la formation rocheuse non-fissurée sur une durée de 1000 ans a été réalisée en s’appuyant sur des paramètres mesurés directement ou obtenus par modélisation des essais d’altération. Elle a montré que les transformations engendrées par le stockage de CO2 sous une roche de couverture homogène restent très limitées spatialement / A promising solution to reduce anthropogenic emissions of greenhouse effect gases consists in the injection and long-term storage of a part of the industrial carbon dioxide discharges in underground formations. These formations must be composed of a reservoir surrounded by tight caprocks, which represent the first barrier preventing fluids migration. The characterization of their confining properties and of their evolution in presence of CO2 is thus a key element regarding a storage site security. This work presents a methodology allowing the measurement of caprocks transport parameters and the consequences of an alteration under representative conditions of deep aquifers storage. This methodology was applied to carbonate rocks from the Paris basin. The breakthrough pressure, the diffusion coefficient of CO2 dissolution products, and the permeability, controlling parameters of leakage mechanisms, were measured before and after alteration of the materials by reaction with a CO2-saturated brine under reservoir thermodynamic conditions (about 80°C and 100 bar). Results revealed a satisfactory global behaviour under these aggressive conditions, but also a strong diminution of the confinement potential in presence of initial structural faults (sealed fractures, large-diameter pores…) forming higher-permeability zones. A numeric simulation describing the evolution of a homogeneous rock formation during 1000 years was also realized based on parameters directly measured or obtained by modelling of the alteration experiments. It showed that the transformations brought by the CO2 storage under a rock formation with no initial faults remain very localized spatially

This work focuses on the issue of acoustic diffusers. The introductory chapter describes the necessary theory of the sound distribution through enclosed space. Acoustic fields are also described. A description of the different diffusion element types and theirs design methods follows. It focuses mainly on design, which uses pseudo-random mathematical sequences. The aim of the work is to produce several types of acoustic diffusors and to verify their diffusion properties by means of measurements. The work uses the AFMG Reflex to simulate the diffusion properties of the proposed elements. Further, the thesis contains a description of the diffusion properties measurement process by the boundary plane method and the process of evaluating the measured data using the Matlab program.

Tato práce se zabývá studiem fluorescenčně značeného hyaluronanu, konkrétně rhodaminylamino hyaluronátu sodného (Hya-Rh, 40 kDa), pomocí dvouohniskové fluorescenční korelační spektroskopie (2f-FCS). Nejdříve byla prostudována literatura týkající se využití FCS techniky v koloidní chemii a při studiu polymerů, přičemž následně byly shrnuty veškeré poznatky o využití 2f-FCS metody. Na základě prvotních měření byl zjištěn vhodný postup přípravy a způsob uchovávání vzorku Hya-Rh používaném pro následující experimenty. Záhy byly prostudovány možné vlivy koncentrace Hya-Rh na jeho difúzní charakteristiky jak ve vodě, tak ve fyziologickém roztoku. Následně bylo studováno chování Hya-Rh a vliv koncentrace solí alkalických kovů ve vodných roztocích těchto solí a fluorescenčně značeného hyaluronanu. Poté bylo sledováno chování Hya-Rh v závislosti na koncentraci velmi nízkomolekulárního hyaluronanu (VLMW HA, 404 kDa) v čisté vodě i ve fyziologickém roztoku, přičemž získané výsledky byly mezi sebou porovnány. Nakonec bylo využití 2f-FCS metody celkově zhodnoceno a popsáno z hlediska studia chování fluorescenčně značeného hyaluronanu v roztocích.

Title: Diffusion of native defects and impurities in CdTe/CdZnTe. Author: Lukáš Šedivý Author's e-mail address: luky.sedivy@seznam.cz Department: Institute of Physics of Charles University Supervisor: Doc. Ing. Eduard Belas, CSc. Supervisor's e-mail address: belas@karlov.mff.cuni.cz Abstract: In this thesis, the influence of structural defects on the electrical and de- tection characteristics of CdTe material was investigated. The performed research fo- cused on the reduction of structural defects in the material by annealing in Cd or Te vapor, while preserving acceptable features for X-ray and γ-ray detection. The mate- rial was characterized by measurement of the electrical resistivity and concentration and mobility of free carriers. Tellurium and cadmium inclusions were studied using infrared microscope. The static and dynamic properties of defect structures at high temperatures and de- fined Cd pressures was investigated, as well, and chemical diffusion coeficients describing the dynamic properties of these defects were experimentally determined. Keywords: monocrystal CdTe, structural defects in semiconductors, annealing in Cd or Te, chemical diffusion coefficient, γ-ray detectors. 1

Ausgangspunkt der Untersuchungen ist eine signifikante Veränderung des elektrochemischen Abscheidungsverhaltens von Silber bei Wechsel des Elektrolytsystems vom technisch eingesetzten salpetersauren System zu einem methansulfonsauren System. Im letztgenannten wird eine für Silber unübliche Kompaktabscheidung an einer Kathode möglich. Die Grundlagenuntersuchungen konnten zeigen, dass eine Erhöhung der Abscheidungspolarisation die Veränderung hervorruft. Ursächlich für diese erhöhte Abscheidungspolarisation ist nach Auswertung der vorhandenen Messdaten eine Veränderung der Struktur der elektrochemischen Doppelschicht. Die Veränderung der Abscheidungsform des Silbers ließ sich erfolgreich zur Durchführung von Laborelektrolysen nutzen. Dabei konnten bei Stromdichten bis zu 900 A/m^2 kompakte Silberniederschläge erhalten werden. Die Gehalte kritischer Verunreinigungen der Silberraffinationselektrolyse, Blei, Kupfer und Palladium, konnten in den meisten Fällen unterhalb der geltenden technischen Spezifikationen gehalten werden. Eine technische Umsetzung ist demnach ausgehend von den Untersuchungen möglich.:1 Einleitung 1 2 Grundlagen zur elektrolytischen Metallabscheidung 2.1 Elektrochemische Kinetik 2.2 Phasengrenze Kathode-Elektrolyt 2.3 Polarisation 2.3.1 Durchtrittspolarisation 2.3.2 Diffusionspolarisation 2.3.3 Reaktionspolarisation 2.3.4 Kristallisationspolarisation 2.4 Stofftransport 2.4.1 Diffusion 2.4.2 Migration 2.4.3 Konvektion 2.5 Durchtritt an der Phasengrenze 2.6 Metallkristallisation 2.6.1 Keimbildung 2.6.2 Keimwachstum 2.6.3 Inhibition 2.6.4 Elektrokristallisation bei gleichzeitiger Inhibition 3 Elektrolytische Raffination von Silber 3.1 Grundlagen zur Silberraffination 3.2 Verunreinigungen von Feinsilber durch Kupfer, Palladium und Blei 3.3 Technische Umsetzung durch die Möbius-Elektrolyse 3.4 Einsatz von Additiven zur Verbesserung der Kathodenqualität 4 Präzisierung der Aufgabenstellung 33 5 Experimentelle Charakterisierung des Systems 5.1 Beschreibung der Silberabscheidung aus Silbermethansulfonat 5.1.1 Angewandte Messmethoden 5.1.2 Experimentelle Vorgehensweise 5.1.3 Charakterisierung der Abscheidungskinetik 5.1.4 Messung des Diffusionskoeffizienten für Ag+ 5.1.5 Charakterisierung der Kristallisation 5.1.6 Ableitung der 5.2 Applikationsbeispiel 5.2.1 Versuchsdurchführung 5.2.2 Optimierung der kathodischen Abscheidungsqualität durch Veränderung der Elektrolytzusammensetzung5.2.3 Verbesserung der Qualität des kathodischen Niederschlags durch Variation der Elektrolysebedingungen 5.2.4 Charakterisierung des Verhaltens typischer Verunreinigungen während der Silberraffination 6 Zusammenfassung Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis Anhang / The investigations started observing a significant change in the electrochemical deposition behaviour of silver when the electrolyte system is changed from the technically used nitric acid system to a methanesulfonic acid system. In the latter system a compact deposition on a cathode, unusual for silver, becomes possible. The basic investigations could show that an increase in deposition polarization causes the change. The reason for this increased deposition polarization is, according to evaluation of the existing measurement data, a change in the structure of the electrochemical double layer. The change in the deposition form of the silver could be successfully used for laboratory electrolysis. Thereby, compact silver deposits could be obtained at current densities up to 900 A/m^2. The contents of critical impurities of the silver refining electrolysis, lead, copper and palladium, could in most cases be kept below the applicable technical specifications. A technical implementation is therefore possible based on the investigations. Translated with www.DeepL.com/Translator (free version):1 Einleitung 1 2 Grundlagen zur elektrolytischen Metallabscheidung 2.1 Elektrochemische Kinetik 2.2 Phasengrenze Kathode-Elektrolyt 2.3 Polarisation 2.3.1 Durchtrittspolarisation 2.3.2 Diffusionspolarisation 2.3.3 Reaktionspolarisation 2.3.4 Kristallisationspolarisation 2.4 Stofftransport 2.4.1 Diffusion 2.4.2 Migration 2.4.3 Konvektion 2.5 Durchtritt an der Phasengrenze 2.6 Metallkristallisation 2.6.1 Keimbildung 2.6.2 Keimwachstum 2.6.3 Inhibition 2.6.4 Elektrokristallisation bei gleichzeitiger Inhibition 3 Elektrolytische Raffination von Silber 3.1 Grundlagen zur Silberraffination 3.2 Verunreinigungen von Feinsilber durch Kupfer, Palladium und Blei 3.3 Technische Umsetzung durch die Möbius-Elektrolyse 3.4 Einsatz von Additiven zur Verbesserung der Kathodenqualität 4 Präzisierung der Aufgabenstellung 33 5 Experimentelle Charakterisierung des Systems 5.1 Beschreibung der Silberabscheidung aus Silbermethansulfonat 5.1.1 Angewandte Messmethoden 5.1.2 Experimentelle Vorgehensweise 5.1.3 Charakterisierung der Abscheidungskinetik 5.1.4 Messung des Diffusionskoeffizienten für Ag+ 5.1.5 Charakterisierung der Kristallisation 5.1.6 Ableitung der 5.2 Applikationsbeispiel 5.2.1 Versuchsdurchführung 5.2.2 Optimierung der kathodischen Abscheidungsqualität durch Veränderung der Elektrolytzusammensetzung5.2.3 Verbesserung der Qualität des kathodischen Niederschlags durch Variation der Elektrolysebedingungen 5.2.4 Charakterisierung des Verhaltens typischer Verunreinigungen während der Silberraffination 6 Zusammenfassung Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis Anhang

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