Submitted by Marco Antonio Oliveira da Silva (maosilva@ipen.br) on 2017-11-08T16:29:11Z No. of bitstreams: 0 / Made available in DSpace on 2017-11-08T16:29:11Z (GMT). No. of bitstreams: 0 / Nesse trabalho foram produzidas nanopartículas (NPs) de Gd2O3 e Er2O3 para aplicação como radiossensibilizadores em feixes de radioterapia. Elas foram sintetizadas no Laboratório de Interações Hiperfinas do IPEN pelo método da decomposição térmica e caracterizadas utilizando difração de raios-X, para verificar a estrutura cristalina, microscopia eletrônica de transmissão, para obter informações sobre forma, tamanho e distribuição de tamanho, análise por ativação neutrônica, por meio da qual foi possível determinar a pureza das amostras e calcular a concentração de gadolínio e érbio. Medições de magnetização e de espectroscopia de correlação angular γ-γ perturbada (PAC) foram realizadas a fim de estudar o comportamento magnético e a interação quadrupolar das partículas, respectivamente. Os resultados da caracterização mostram a formação de uma estrutura cristalina do tipo bixbyite, com aproximadamente 5 nm de diâmetro e estreita distribuição de tamanho, para as amostras pós-síntese. A determinação da massa de terra-rara em cada amostra foi importante para realizar a normalização nas medições de susceptibilidade magnética, tornando possível a visualização de um grande aumento na magnetização abaixo de 30 K, nas amostras pós-síntese, o que não é observado em partículas maiores, além de um aumento no momento magnético efetivo das NPs em relação aos respectivos bulks e uma mudança na temperatura de ordenamento antiferromagnético para o Er2O3. Os resultados da espectroscopia PAC evidenciam possíveis efeitos de superfície. A falta de uma frequência bem definida nas amostras de 5 nm indicam que a quantidade de 111In(111Cd) na superfície da partícula é maior do que no interior da mesma, fazendo com que a interação hiperfina do núcleo de prova com o host não seja evidente. Já a união da técnica de difração de raios-X com a espectroscopia PAC foi fundamental para o entendimento do dano causado às partículas pela irradiação com 60Co. Quanto às medições de radiossensibilização a dosimetria Fricke gel foi fundamental para a verificação de um fator de aumento de dose (DEF) de até 1,67 e 1,09 para NPs de Gd2O3 irradiadas com 60Co e 6MV, respectivamente. Nas mesmas condições, para as amostras de Er2O3, foram encontrados valores de DEF de até 1,37 e 1,06. Isso comprova os efeitos radiossensibilizadores dessas NPs. Os resultados alcançados nesse trabalho não apenas fornecem dados importantes para o estudo de NPs de terra-rara na área de física da matéria condensada como também uma base sólida para a aplicação desses elementos como radiossensibilizadores em feixes de radioterapia, possibilitando a utilização da imagem por ressonância magnética para localizar e obter a concentração dessas NPs dentro do paciente, aumentando assim a eficiência do tratamento do câncer. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

This thesis work deals with different aspects of the chemistry of La(III) and Gd(III) complexes, their interaction with DNA and proteins, photo-induced cleavage of double-stranded DNA, photocytotoxic effect on cancer cells, cell death mechanism and cellular localization behaviour. Chapter I gives an introduction to the metal-based anticancer agents with special emphasis on clinically used drugs and the growing field of lanthanide therapeutics. An overview of the current strategies of cancer treatment, especially photodynamic therapy (PDT), is presented. Mode of small molecule-DNA interactions and the mechanistic aspects associated with DNA photodamage reactions and PDT effect are discussed with selected examples of compounds that are known to photocleave DNA on exposure to light of different wavelengths. A brief discussion on the various therapeutic applications of the lanthanide compounds is also made. Chapter II presents the synthesis, characterization, DNA binding, BSA binding, photo-induced DNA cleavage activity and photocytotoxicity of La(III) and Gd(III) complexes of phenanthroline bases to explore the UV-A light-induced DNA cleavage activity and photocytotoxicity of the complexes. Chapter III describes the synthesis, characterization, DNA binding, photo-induced DNA cleavage activity and photocytotoxicity of La(III) and Gd(III) complexes of phenanthroline bases with an aim to improve the design of the complexes to achieve better solution stability and DNA binding of the complexes. Chapter IV presents the synthesis, characterization, DNA binding, and UV-A light-induced DNA photocleavage activity and photocytotoxicity of La(III) and Gd(III) complexes of pyridyl phenanthroline bases with an objective to improve the photoactivity of the complexes by introducing an additional pyridyl group. Cell death mechanism and confocal microscopic studies are also carried out to gain more insight into the PDT effect caused by light in the presence of the complex. Chapter V describes the synthesis and characterization of La(III) and Gd(III) complexes of terpyridine bases and acetylacetonate to study the complexes as a new class of photosensitizers to explore their DNA photocleavage activity and photocytotoxicity in HeLa cells. Effect of attaching a glucose moiety to the acetyl acetone (Hacac) ligand has been studied. The cellular uptake behaviour of the La(III) pyrenyl-terpyridine complexes has also been investigated. Finally, Chapter VI presents the synthesis and characterization of curcumin and glycosylated curcumin La(III) and Gd(III) complexes having terpyridine base with an objective to study the photoactivated anticancer activity of the complexes in visible light. This chapter describes the visible light-induced DNA cleavage activity and photocytotoxicity of the complexes by exploiting curcumin and glycosylated curcumin as the photosensitizer ligands. Study on the cellular uptake behavior of curcumin La(III) complexes having pyrenyl terpyridine ligand is also presented. The references have been assembled at the end of each chapter and indicated as superscript numbers in the text. The complexes presented in this thesis are represented by bold-faced numbers. Crystallographic data of the complexes which are characterized structurally by single crystal X-ray crystallography are provided in CIF format in the enclosed CD (Appendix-I). Due acknowledgements have been made wherever the work described is based on the findings of other investigators. Any unintentional omission that might have happened due to oversight or mistake is sincerely regretted.

Polykristallines Sr3Gd2[BO3]4 (SGB) konnte mithilfe einer stöchiometrischen Mischung aus SrCO3, Gd2O3 und B2O3 durch zweimaliges Sintern bis 1.350 °C phasenrein erzeugt werden. Ein Exzess von 3 Ma% B2O3 musste der Mischung beigesetzt werden, um das an B2O3 gebundene Wasser auszugleichen [125]. Kristalle des SGB ließen sich mit verschiedenen Orientierungen erfolgreich mit dem Czochralski-Verfaren synthetisieren. Unter Einsatz eines arteigenen, b-orientierten Keimes, einer Translation von 1 mm/h und einer Rotation von 4 /min konnten Kristalle mit guter Qualität bei hoher Erfolgsrate produziert werden. Bei den gezüchteten Kristallen waren keine Segregationserscheinungen zwischen Gadolinium und Strontium feststellbar. Jedoch weist das Auftreten von Fremdphasen (vor allem Gd2O3) in wenigen Kristallen auf eine mögliche, geringfügige Bevorzugung des Sr in der Struktur hin. Die Härte des Materials ist mit ca. 5,5 nach Mohs bestimmt, die Dichte mit 5,15(1) g/cm3. SGB ist nicht hygroskopisch, lässt sich aber in mineralischen Säuren lösen. Die Schmelztemperatur konnte mit 1.461+/-5 °C bestimmt werden. Einkristallines SGB besitzt ein Transmissionsfenster zwischen 215-3.450 nm. Das entspricht einer Bandlücke von 5,4 eV. In diesem Bereich werden über 80% des eingestrahlten Lichtes transmittiert. Im ultravioletten Spektrum finden sich für Gd charakteristische Absorptionsbanden, die durch Elektronenübergänge erzeugt werden. Im mittleren Infrarotbereich lassen sich um die Absorptionskante mehrere Absorptionsbanden, deren Ursache ungeklärt ist, feststellen. Sie stehen offensichtlich im Zusammenhang mit dem Auftreten von [BO3]3- -Gruppen, da sie auch bei anderen Boraten, wie dem Ca4Gd[O|(BO3)3] [99], vorkommen. Gepulvertes SGB weist im Bereich von 550-1.600 cm-1 zahlreiche Absorptionsbanden, die auf verschiedene Schwingungen innerhalb der [BO3]3- -Gruppe zurückgeführt werden können, auf. Es folgen zu kleineren Wellenzahlen hin vermutlich Sr-O- und Gd-O-Schwingungen. Die thermische Ausdehnung von SGB-Kristallen ist anisotrop sowohl zwischen den kristallographischen Richtungen a, b und c als auch über die Temperatur innerhalb einer Richtung. Sie kann im Mittel zwischen 150-830 °C mit alpha11=18,1(2)*10-6/K, alpha22=8,9(3)*10-6/K und alpha33=20,3(4)*10-6/K angenommen werden. Die Ausdehnungskurven deuten mehrere Effekte an, wobei ein Effekt im Bereich von 450-700 °C und vermutlich zwei weitere im Bereich von 800-1.000 °C zu beobachten sind. Aufgrund der Stetigkeit der Kurve ist wahrscheinlich von Phasenübergängen höherer Ordnung auszugehen. Zur Struktur des SGB konnten wichtige Grundverständnisse gewonnen werden. So lässt sich die Struktur bei Raumtemperatur nicht durch eine orthorhombisch zentrische Metrik beschreiben, da die Einzelreflexe bei Einkristallmessungen eine Aufspaltung im Bereich von 0,1 ° zeigen. Dies deutet auf das Vorhandensein von Zwillingen und auch auf eine mögliche monokline Metrik hin. Es fällt dabei besonders auf, dass die Aufspaltung mit zunehmendem Theta-Winkel nicht größer wird, so dass auch andere Phänomene für die Reflexaufspaltung verantwortlich sein könnten. Dennoch ergeben die ermittelte Raumgruppe Pnam, die zugehörigen Gitterparameter (a0=0,7408 nm, b0=0,8757 nm, c0=1,6057 nm) und Atomkoordinaten ein vereinfachtes Modell zur Veranschaulichung der Struktur. Hoch- und Raumtemperaturstruktur sind bis 700 °C unter Annahme des vereinfachten Modells isomorph, wobei die Gitterparameter entsprechend der Ausdehnung vergrößert sind. Die Gd- und Sr-Positionen sind untereinander mischbesetzt. Außerdem deutet sich eine Positionsfehlordnung einer Sauerstoff-Position an, der Ligand eines Borions auf spezieller Lage ist. Hinweise auf die korrekte Struktur liefern die entdeckten Phasenübergänge und Hochtemperatur-Einkristalldaten. Der in der Dilatometrie entdeckte Effekt zwischen 450-700 °C korreliert mit dem Rückgang der Reflexaufspaltung, die bei ca. 700 °C nicht mehr sichtbar ist, wobei sich dieser Rückgang vermutlich von Raumtemperatur bis 700 °C erstreckt. Damit bestätigt sich, dass der erst genannte Effekt als Phasenübergang höherer Ordnung aufgefasst werden kann. Die festgestellte Positionsfehlordnung von Sauerstoff verringert sich mit steigender Temperatur. Die Mischbesetzung ändert sich ebenfalls bis ca. 500 °C. Beide Effekte sowie auch größeren Schwingungsellipsoide der Sauerstopositionen um die allgemeine Borlage sind vermutlich Ausdruck für den stattfindenden Phasenübergang und verstärken die Annahme einer Zwillingsbildung.

Background: Glioblastoma (GBM) is the most common and malignant primary brain tumor. It is a rapidly progressing tumor that infiltrates the adjacent healthy brain tissue and is difficult to treat. Despite modern treatment including surgical resection followed by radiochemotherapy and adjuvant chemotherapy, the outcome remains poor. The median overall survival is 10-12 months. Neuroimaging is the most important diagnostic tool in the assessment of GBMs and the current imaging standard is contrast-enhanced magnetic resonance imaging (MRI). Positron emission tomography (PET) has been recommended as a complementary imaging modality. PET provides additional information to MRI, in biological behavior and aggressiveness of the tumor. This study aims to investigate if the combination of PET and MRI can improve the diagnostic assessment of these tumors. Patients and methods: In this study, 22 patients fulfilled the inclusion criteria, diagnosed with GBM, and participated in all four 18F-fluorothymidine (FLT)-PET/MR examinations. FLT-PET/MR examinations were performed preoperative (baseline), before the start of the oncological therapy, at two and six weeks into therapy. Optimization of an adaptive thresholding algorithm, a batch processing pipeline, and image feature extraction algorithms were developed and implemented in MATLAB and the analyzing tool imlook4d. Results: There was a significant difference in radiochemotherapy treatment response between long-term and short-term survivors’ tumor volume in MRI (p<0.05), and marginally significant (p<0.10) for maximum standard uptake value (SUVmax), PET tumor volume, and total lesion activity (TLA). Preoperative short-term survivors had on average larger tumor volume, higher SUV, and total lesion activity (TLA). The overall trend seen was that long-term survivors had a better treatment response in both MRI and PET than short-term survivors.  During radiochemotherapy, long-term survivors displayed shrinking MR tumor volume after two weeks, and almost no remaining tumor volume was left after six weeks; the short-term survivors display marginal tumor volume reduction during radiochemotherapy. In PET, long-term survivors mean tumor volumes start to decrease two weeks into radiochemotherapy. Short-term survivors do not show any PET volume reduction two and six weeks into radiochemotherapy. For patients with more or less than 200 days progression-free survival, PET volume and TLA were significantly different, and MR volume only marginally significant, suggesting that PET possibly could have added value. Conclusion: The combination of PET and MRI can be used to predict radiochemotherapy response between two and six weeks, predicting overall survival and progression-free survival using MR and PET volume, SUVmax, and TLA. This study is limited by small sample size and further research with greater number of participants is recommended.

Amyloidosis is a term used for a whole group of diseases caused by deposition of a substance called amyloid into different tissues. Amyloid may be produced by a range of pathologic processes. Heart affliction is typical for only several types of amyloidoses. Heart involvement is then the patient`s prognosis major limiting factor. Diagnosis of heart amyloidosis is difficult especially for nonspecific symptoms and nonspecific findings obtained during common diagnostic procedures. The aim of this thesis was to evaluate usefulness of novel diagnostic methods, namely cardiac magnetic resonance with gadolinium enhancement and a simplified echocardiographic evaluation of left ventricular longitudinal strain, in diagnosing amyloid cardiomyopathy. In our first study we examined 22 patients with light chain amyloidosis by echocardiography and also with cardiac magnetic resonance with late gadolinium enhancement. We compared morphologic and functional parameters acquired by magnetic resonance examination, which is considered a gold standard for morphologic and functional measurements, with values obtained by echocardiographic measurement. Afterwards we evaluated the presence and eventually pattern of late gadolinium enhancement during cardiac magnetic resonance exam. From acquired data we conclude that the...

In der Arbeit wurden die zwei ternären Oxide GdScO3 und AlTiOx strukturell und elektrisch charakterisiert und in laterale AlGaN/GaN-MISHEMTs integriert. GdScO3 wächst hexagonal und epitaktisch bei einer Abscheidung mittels PLD bei 700°C auf einer AlGaN/GaN Heterostruktur auf. Die demonstrierten MISHEMTs zeigen einen deutlich verringerten Gate-Leckstrom. Zeit- und beleuchtungsabhängige Drain-Strom Messungen im ausgeschaltetem Transistor weisen allerdings auf photoinduzierte Trapzustände mit langer Lebensdauer im Oxid hin, die den Drain-Leckstrom limitieren. Die AlTiOx Mischoxide wurden mittels ALD abgeschieden. Dabei wurde die Stöchiometrie über das Zyklenverhältnis zwischen Al2O3 und TiO2 variiert. Es konnte gezeigt werden, dass der Brechungsindex, die Permittivität, die Bandlücke und das Bandalignment zum GaN über die Stöchiometrie eingestellt werden können. Durch die Implementierung eines high-k last Prozesses konnten schaltbare MISHEMTs prozessiert werden. Durch die Simulation der Bandstruktur konnten die Einsatzspannungsverschiebung und ein Maximum des Drain-Stroms im ausgeschaltetem Zustand über die Ermittlung der Barrierendicke für Elektronen erklärt werden. Für eine Passivierung mit TiO2 wurde ein um 2,5 Größenordnungen reduzierter Drain-Leckstrom bei gleichzeitig nur minimal verschobener Einsatzspannung gemessen.:Inhaltsverzeichnis 1 Einleitung 7 2 Grundlagen 9 2.1 Der III-V Halbleiter Galiumnitrid . . . . . . . . . . . . . . . . . . . . . 9 2.2 Der Hetero-Feldeffekttransisor . . . . . . . . . . . . . . . . . . . . . . . 10 2.3 Performance Einschränkungen am unpassivierten HFET . . . . . . . . 14 2.4 Gatedielektrika für MISHEMTs . . . . . . . . . . . . . . . . . . . . . . 17 2.4.1 Verwendete Dielektrika . . . . . . . . . . . . . . . . . . . . . . . 19 2.4.2 Limitationen in MISHEMTs . . . . . . . . . . . . . . . . . . . . 23 2.5 Atomlagenabscheidung . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2.5.1 Der ALD-Prozess . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2.5.2 Abscheidung ternärer Verbindungen . . . . . . . . . . . . . . . . 27 3 Charakterisierungsmethoden 31 3.1 Kapazitäts-Spannungs-Messungen an MIS-Kondensatoren . . . . . . . . 31 3.2 Photo-assisted Kapazitäts-Spannungsmessungen . . . . . . . . . . . . . 34 3.3 Messungen am Transistor . . . . . . . . . . . . . . . . . . . . . . . . . 35 4 Probenherstellung 39 4.1 Atomlagenabscheidung . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 4.2 Prozessoptimierung am HFET . . . . . . . . . . . . . . . . . . . . . . . 43 4.2.1 Mesa-Ätzung . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 4.2.2 Formierung der ohmschen Kontakte . . . . . . . . . . . . . . . . 47 4.3 Strukturierung der Oxide . . . . . . . . . . . . . . . . . . . . . . . . . . 50 5 Gadoliniumscandiumoxid 53 5.1 Strukturelle Charakterisierung . . . . . . . . . . . . . . . . . . . . . . . 53 5.2 PhotoCV-Messungen . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 5.3 MISHEMT mit GdScO3 . . . . . . . . . . . . . . . . . . . . . . . . . . 57 5.4 Zusammenfassung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 6 Aluminium-Titanoxid Mischschichten 65 6.1 Voruntersuchungen am TiO2 . . . . . . . . . . . . . . . . . . . . . . . . 65 6.2 Strukturelle Charakterisierung an AlTiOx . . . . . . . . . . . . . . . . 67 6.2.1 Stöchiometrie . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 6.2.2 Kristallisationsverhalten . . . . . . . . . . . . . . . . . . . . . . 70 6.3 Bestimmung des Bandalignments . . . . . . . . . . . . . . . . . . . . . 72 6.3.1 UV/Vis Messungen . . . . . . . . . . . . . . . . . . . . . . . . . 72 6.3.2 Röntgenphotoelektronenspektroskopie . . . . . . . . . . . . . . . 74 6.3.3 Bandalignment zum GaN . . . . . . . . . . . . . . . . . . . . . 77 6 Inhaltsverzeichnis 6.4 Elektrische Charakterisierung . . . . . . . . . . . . . . . . . . . . . . . 79 6.4.1 CV-Messungen . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 6.4.2 IV-Messungen . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 6.4.3 PhotoCV-Messungen . . . . . . . . . . . . . . . . . . . . . . . . 82 6.5 Zusammenfassung der AlTiOx Charakterisierung . . . . . . . . . . . . . 86 6.6 MISHEMTs mit AlTiOx . . . . . . . . . . . . . . . . . . . . . . . . . . 88 6.6.1 high-k first MISHEMTs . . . . . . . . . . . . . . . . . . . . . . . 88 6.6.2 High-k last MISHEMTs . . . . . . . . . . . . . . . . . . . . . . . 89 6.7 Einordnung der Transistorergebnisse . . . . . . . . . . . . . . . . . . . 94 7 Zusammenfassung 99 Anhang 103 Abkürzungsverzeichnis 111 Symbolverzeichnis 113 Abbildungsverzeichnis 115 Tabellenverzeichnis 121 Literatur 123 Publikationen 141 Danksagung 143

Gadolinium-based contrast agents (GBCAs) are in widespread use to enhance magnetic resonance angiography images for evaluating vascular pathology. However, there are safety concerns and limitations regarding the use of GBCAs. It has been shown that the magnetic resonance imaging (MRI) signal intensity (T1-weighted images) in some of the brain's tissues is higher for patients who had multiple exposures to GBCAs compared to patients who had never had exposure to GBCAs. This implies that GBCAs are not sufficiently removed from body such that GBCAs may potentially have long-term effects on the human body. These potential safety concerns have led to an increased interest in alternative contrast agents. Methemoglobin (metHb) and oxygen-free hemoglobin (HHb) are two forms of hemoglobin with paramagnetic properties. It has been shown that the T1-weighted signal intensity of blood is changed during MRI scans for metHb and HHb, leading to enhanced contrast of MRI images. The ability of metHb and HHb to change the signal intensity has led to the idea that they can be used as effective contrast agents. MetHb can be made by exposing oxyhemoglobin (oxyHb) to nitric oxide (NO) and HHb can be made by removing the oxygen from hemoglobin using nitrogen (N2). In this study, a new gas delivery system was developed to make metHb and HHb. The new gas delivery system was developed to have greater experimental control compared to the PermSelect hollow-fiber module that was used in preliminary studies to make metHb. The same system can be used to make HHb. Initial experiments showed significant amounts of undesired nitrite (NO2-) formation during metHb formation due to the presence of contaminants in the NO gas source. To minimize this problem, flow of NO from the gas source was bubbled in a sodium hydroxide solution in order to reduce the NO2- concentration. Following metHb formation, continuous delivery of NO also led to the formation of ferrous nitrosyl hemoglobin (HbIINO). MRI studies showed that HbIINO can also increase the signal intensity of an MRI image. It is unknown as to whether metHb, HHb, or HbIINO would be a stronger and more appropriate contrast agent and to what extent the T1-weighted signal is affected by the concentration. This study evaluated T1-weighted images of blood samples over a range of metHb and HHb concentrations, as well as HbIINO concentrations. Comparison of T1 values showed that metHb is the strongest contrast agent and that HHb is a relatively weak contrast agent. This study showed for the first time that HbIINO can provide a contrast effect, although not as strong as metHb but stronger than HHb. With metHb providing a viable contrast between 10-20%, metHb has the potential to be a safe and effective contrast agent since it can be naturally converted back to hemoglobin.

No description available.

No description available.

This master thesis project was performed in collaboration with Scania CV AB, Engine Materials group. The purpose with the project was to investigate different ceramic TBC (Thermal Barrier Coating) thermal insulation properties inside the combustion chamber. Experimental testing was performed with a Single-Cylinder engine with TBC deposited on selected components. A dummy-valve was developed and manufactured specifically for this test in order to enable a water cooling system and to ease the testing procedure. The dummy-valve consists of a headlock, socket, valve poppet and valve shaft. Additionally, a copper ring is mounted between the cylinder head and the valve poppet to seal the system from combustion gases. Thermocouples attached to the modified valve poppet and valve shaft measured the temperature during engine test to calculate the heat flux. The TBCs consisted of three different materials: 7-8% yttrium-stabilized zirconia (8YSZ), gadolinium zirconia and lanthanum zirconia. The 8YSZ TBC was tested as standard, but also with microstructural modifications. Modifications such as pre-induced segmented cracks, nanostructured zones and sealed porosity were used. The results indicated that the heat flux of 8YSZ-standard, 8YSZ-nano and 8YSZ-segmented cracks was in level with the steel reference. In the case of 8YSZ-sealed porosity the heat flux was measured higher than the steel reference. Since 8YSZ-standard and 8YSZ-sealed porosity are deposited with the same powder it is believed that the high heat flux is caused by radiative heat transfer. The remaining samples have had some microstructural changes during engine testing. 8YSZ-nano had undergone sintering and its nanostructured zones became fewer and almost gone after engine testing leading to less heat barrier in the top coat of the TBC. However, for 8YSZ-segmented cracks and gadolinium zirconia lower heat flux was measured due to the appearance of horizontal cracks. These cracks are believed to act as internal barriers as they are orientated perpendicular to the heat flow. During long-time (5 hour) engine tests the 8YSZ-standard exhibited the same phenomena: a decrease in heat flux due to propagation of horizontal cracks. One-dimensional heat flux was not achieved and the main reason for that was caused by heating and cooling of the shafts outer surface. However, the dummy-valve system has proven to be a quick, easy and stable to perform tests with a Single-Cylinder engine. Both water-cooling and long-time engine tests were conducted with minor issues. The dummy-valve has been further developed for future tests. Changes to the valve shaft are the most remarkable: smaller diameter to reduce heat transfer and smaller pockets to ensure better thermocouple positioning. Another issue was gas leakage from the combustion chamber through the copper ring and valve poppet joint. The copper ring will be designed with a 1 mm thick track to improve sealing, hence better attachment to the valve poppet.