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Morvan, Frédéric. "Effet préventif des RGTA sur des mucites induites par du 5-Fluoruracile chez le hamster : études in vivo et in vitro." Paris 7, 2003. http://www.theses.fr/2003PA077078.
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Noriega, Esteban Núria. "The Rtg1 and Rtg3 proteins are novel transcription factors regulated by the yeast hog1 mapk upon osmotic stress." Doctoral thesis, Universitat Pompeu Fabra, 2009. http://hdl.handle.net/10803/7158.
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La adaptación de la levadura Saccharomyces cerevisiae a condiciones de alta osmolaridad está mediada por la vía de HOG ((high-osmolarity glycerol). La activación de esta vía induce una serie de respuestas que van a permitir la supervivencia celular en respuesta a estrés. La regulación génica constituye una respuesta clave para dicha supervivencia. Se han descrito cinco factores de transcripción regulados por Hog1 en respuesta a estrés osmótico. Sin embargo, éstos no pueden explicar la totalidad de los genes regulados por la MAPK Hog1. En el presente trabajo describimos cómo el complejo transcripcional formado por las proteínas Rtg1 y Rtg3 regula, a través de la quinasa Hog1, la expresión de un conjunto específico de genes. Hog1 fosforila Rtg1 y Rtg3, aunque ninguna de estas fosforilaciones son esenciales para regulación transcripcional en respuesta a estrés. Este trabajo también muestra cómo la deleción de proteínas RTG provoca osmosensibilidad celular, lo que indica que la integridad de la vía de RTG es esencial para la supervivencia celular frente a un estrés osmótico.In Saccharomyces cerevisiae the adaptation to high osmolarity is mediated by the HOG (high-osmolarity glycerol) pathway, which elicits different cellular responses required for cell survival upon osmostress. Regulation of gene expression is a major adaptative response required for cell survival in response to osmotic stress. At least five transcription factors have been reported to be controlled by the Hog1 MAPK. However, they cannot account for the regulation of all of the genes under the control of the Hog1 MAPK. Here we show that the Rtg1/3 transcriptional complex regulates the expression of specific genes upon osmostress in a Hog1-dependent manner. Hog1 phosphorylates both Rtg1 and Rtg3 proteins. However, none of these phosphorylations are essential for the transcriptional regulation upon osmostress. Here we also show that the deletion of RTG proteins leads to osmosensitivity at high osmolarity, suggesting that the RTG-pathway integrity is essential for cell survival upon stress.
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Velím, Michael. "Defektoskopie s využitím RTG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-399582.
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This diploma thesis deals with a defect detection with X-rays in the manufacturing procedure in the electrotechnical field. The work summarises the knowledge about technical possibilities of an X-ray device Cougar of YXlon company. Part of the work is focusing on scanning in 2D, 3D visualization and automatic analysis. The thesis describes inspection methods of a connector connection, the quality of a soldered joint and an encapsulated product.
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Pelz, Johann. "Immunhistochemische Analyse vaskulärer und glialer Veränderungen im Rattenhirn nach fokaler zerebraler Ischämie und Hyperbarer Sauerstofftherapie." Doctoral thesis, Universitätsbibliothek Leipzig, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-115141.
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Der ischämische Schlaganfall ist ein akutes Krankheitsbild mit großer medizinischer und sozioökonomischer Bedeutung. Eine zentrale Rolle in der Pathophysiologie spielt hierbei die Neurovaskuläre Einheit (NVU), deren wichtigste Funktion in der Gewährleistung der Blut-Hirn-Schranke (BBB) besteht. Die vorliegende Arbeit beschäftigt sich mit der weiteren immunhistochemischen Charakterisierung vaskulärer und zellulärer Komponenten der NVU und der Analyse der BBB-Permeabilität beim thrombembolischen Schlaganfallmodell der Ratte. Darüber hinaus wird ein immunhistochemisches Verfahren entwickelt, mit dem FITC-Albumin und biotinyliertes Ratten-IgG in dauerhaft stabile Diaminobenzidin-Addukte überführbar sind, was anschließend die lichtmikroskopische Analyse in Serienschnitten und dadurch eine einfache volumetrische Quantifizierung permeabilitätsgestörter Areale erlaubt. 25 Stunden nach Induktion der Ischämie kann so im direkten Vergleich von ausgetretenem biotinylierten Ratten-IgG mit FITC-Albumin gezeigt werden, dass sowohl die qualitativ als auch quantitativ ermittelten Verteilungsmuster für beide Markersubstanzen identisch sind.
Ein weiterer Schwerpunkt gilt der Fragestellung, ob bekannte negative Effekte der systemischen Thrombolyse mit rekombinantem Gewebsplasminogenaktivator (rtPA) auf die Integrität der BBB durch eine simultane Hyperbare Sauerstofftherapie (HBO) abgeschwächt werden können. Dabei wird durch die gezielte Untersuchung einzelner Gefäße im permeabilitätsgestörten Areal erstmalig demonstriert, dass HBO zu keiner Stabilisierung einer erhöhten BBB-Permeabilität beim thrombembolischen Schlaganfall der Ratte führt.
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Lundquist, Per. "Certification of Actel Fusion according to RTCA DO-254." Thesis, Linköping University, Department of Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10032.
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In recent years the aviation industry is moving towards the use of programmable logic devices in airborne safety critical systems. To be able to certify the close to fail-safe functionality of these programmable devises (e.g. FPGAs) to the aviation authorities, the aviation industry uses a guideline for design assurance for airborne electronic hardware named RTCA DO-254. At the same time the PLD industry is developing ever more complex embedded system-on-chip solutions integrating more and more functionality on a single chip.
This thesis looks at the problems that rise when trying to certify system-on-chip solutions according to RTCA DO-254. Used as an example of an embedded FPGA, the Actel Fusion FPGA chip with integrated analog and digital functionality will be tested according to the verification guidance. The results show that for the time being, the examined embedded system-on-chip FPGAs can not be verified to be used in airborne safety critical systems.
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Novotný, Lukáš. "Kvantitativní hodnocení kvality CT RTG zobrazení." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218149.
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X-Ray Computed Tomography is irreplaceable medical imaging system. Quantitative evaluation is day to day routine used for clean run of this imaging system. The master’s thesis is focused on quantitative evaluation of first and third generation X-Ray CT. First of all is about subjective and objective evaluation of space and energetic resolution. Space resolution is evaluated in space and frequency domain. Energetic resolution is represent by low contrast resolution method. Application “Kvantitativní hodnocení kvality CT RTG zobrazení” created for this thesis is used for creation of reconstruction image and quantitative evaluation. This application was created with consideration of its usage in subjects about image processing. The master’s thesis contains results of quantitative evaluation X-Ray CT created with this application and proposal of lab work.
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Nikolaev, Simon. "Evaluation of high pressures in grouting using RTGC - a case study." Thesis, KTH, Jord- och bergmekanik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-175147.
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“Real time grouting control method” är ett koncept för att övervaka och bedöma spridningen av injekteringsbruk under injektering. Målet är att kunna använda penetrationsavstånd som stopkriterium och att kunna övervaka hur injekteringsarbetet fortskrider i realtid, vilket skulle göra injekteringsarbetet mer tids- och kostnadseffektivt. Teorin har prövats med data från ett tunnelprojekt i Sverige med kristallint berg från prekambrium-eran, och med data från dammprojekt i Iran och Laos med sedimentärt berg, samtliga med lovande resultat. RTGC-teorin har nyligen vidareutvecklats, där bedömningar och begränsningar angående jacking föreslås, utifrån en kombination av injekteringstryck och spridning av injekteringsbruk. Teorin har tvecklats både för elastisk jacking, där deformationer kan kompenseras för, och för plastisk jacking, där deformationerna är permanenta. Effekterna av höga tryck och jacking kan uppskattas och de eventuella negativa konsekvenserna kvantifieras. Mer specifikt ligger fokus på vilken påverkan sprickdeformationer kan ha på penetrationsavståndet och på transmissiviteten i en spricka. Syftet med detta examensarbete har varit att undersöka vilka effekter höga injekteringstryck har på injekteringsprocessen av en tunnel med avseende på jacking. I examensarbetet har teorin för RTGC använts för att analysera data från ett järnvägstunnelsprojekt i Norge, där betydligt högre injekteringstryck än i Sverige generellt sett används. Teorin har kunnat appliceras på data framgångsrikt, även om mindre anpassningar varit nödvändiga. Orsaken till anpassningarna är att teorin främst är utvecklad för ett mer eller mindre konstant injekteringstryck, samtidigt som ett varierande injekteringstryck i viss utsträckning använts i det norska projektet. Resultaten tyder på att det skulle vara möjligt att spara både tid och pengar med hjälp av RTGC, genom att minska åtgången av både tid och injekteringsbruk. Resultaten antyder även att höga injekteringstryck kan orsaka betydande jacking om geologin och sprickornas orientering och längd är ogynnsamma. Om och i vilken utsträckning jackingen påverkar den slutliga tätningen av bergmassan har emellertid inte kunnat studeras i detta projekt, då data kring inläckage ej varit tillgänglig vid genomförandet av analysen. Vidare visas, trots vissa antaganden och förenklingar i den geologiska modellen, att denna teoretiska modell möjliggör en bedömning av effekterna som injekteringstrycket har på det slutliga resultatet. Detta bör kunna användas för att välja ett optimalt injekteringstryck.The “Real Time Grouting Control Method” is a concept for governing the grout spread during a grouting operation. The goal is to be able to use the penetration length as stop criterion and to be able to monitor the progress of the grouting operation in real-time, which would make grouting operations more efficient in terms of time and cost. The theory has been tested with data from tunnelling projects in Sweden with pre-cambium rock, and with data from dam projects in Iran and in Laos with sedimentary rock, all with promising results. Recently there have been developments in the RTGC-theory that propose jacking limits based on a combination of grout pressure and spread of grout, both for elastic jacking, where deformations can be compensated for, and ultimate jacking, where deformations are permanent. With the theory, the effects of high pressures and elastic jacking can be assessed, and the negative consequences of elastic jacking can be quantified. Specifically, the focus is on the effect that fracture deformation may have on the distance that the grout penetratesinto a fracture, and on the transmissivity of a fracture. The aim of this thesis is to evaluate what effects high grouting pressures may have on the grouting process with respect to jacking. To obtain this, the theory is used to analyse data from a railway tunnel project in Norway, where considerably higher grouting pressures than in Sweden are used. The application of the theory has been successful, even though some minor adaptions have been necessary. The reason for the adaptions is that the RTGC-theory is developed for a more or less constant grouting pressure, while a varying pressure to some extent has been applied in the Norwegian project. The results suggest that using RTGC could save time and money by reducing grouting time and grout volume. The results also suggest that the high grouting pressures may cause considerable jacking if the geology and fracture situation is unfavourable. If and to what extent the jacking affects the final tightness of the rock mass has however not been possible to determine, given that data regarding measured leakage has not been available at the time for this analysis. It is shown that despite assumptions and simplifications in the geological model, using this theoretical approach enables the estimation of the effect that the grouting pressure has on the outcome of the performed grouting, arguably allowing for the optimum grouting pressure to be selected.
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Kabrda, Miroslav. "Zpracování RTG snímků při výzkumu čelistních onemocnění." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219426.
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The subject of this thesis is a method proposed for automated evaluation of the parameters of X-ray of cystic disorders in human jawbones. The main problem in medical diagnostic is the low repeatability due to the subjective evaluation of images without using a tool for image processing. In this thesis are described the basic steps of image processing, various methods of image segmentation and chosen segmentation method live-wire. Selected segments were processed in the ImageJ Java environment. In the cystic regions their basic statistical and shape properties were evaluated. The obtained values were used for learning the classification model (decision tree) in the environment RapidMiner. This model was used to create a plug-in for automatic classification of the type of cysts in the program ImageJ.
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Bainar, Petr. "Modelování rekonstrukce obrazu při CT RTG fluoroskopii." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220045.
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The aim of the thesis is to design and implement a simulator of image reconstruction during x-ray computed tomography fluoroscopy. Apart from quantitative evaluation of particular imaging process parameters influence, the intended program application will lie in optimization of these parameter values. Introductory part is focused on brief theoretical description of x-ray computed tomography imaging process. Emphasis is placed on fluoroscopy-specific approaches, particularly the division of scanned projections into chosen amount of sectors as well as fluoroscopic imaging process evaluation methods. The subsequent part deals with program implementation and its limitations and sketches the possible working framework. Moreover, one of the chapters is devoted to optimization of imaging process parameters measurement. The final part aims at impact analysis of particular process parameters as well as fluoroscopic imaging process optimization approaches. The thesis consists also of a didactic simulator enabling real-time intervention simulation with manual instrument manipulation. Since both simulators are intended for teaching purposes, the thesis is supplemented with a laboratory exercise draft.
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Glenday, Jonathan Daniel. "Biomechanical assessment of RTSA functional outcomes towards optimising the prosthesis configuration." Doctoral thesis, Faculty of Health Sciences, 2018. http://hdl.handle.net/11427/30031.
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Reverse total shoulder arthroplasty (RTSA) alleviates pain and restores function to patients with cuff tear arthropathies or massive rotator cuff tears. The procedure uses a semi-constrained prosthesis to reverse the orientation of the glenohumeral joint, thereby altering the biomechanics of the deltoid and allowing it to restore shoulder function in the presence of an irreparably damaged rotator cuff. However, there are complications that can impact long-term success of RTSA. Adaptations to the design and placement of the prosthesis have been investigated to address these complications and this has led medical device manufacturers to develop divergent implants. This divergence, as well as previous literature regarding RTSA biomechanics, suggest that a configuration that optimises reverse shoulder functional outcomes has yet to be determined and that it can be obtained by combining multiple modifications. A biomechanical assessment framework was established to characterise reverse shoulder function and the effect of modifying prosthesis configuration. It utilised the Newcastle Shoulder Model (NSM) and a custom-made impingement detection algorithm to simulate seven standardised motions that either elevated or rotated the humerus. Four outcome measures (deltoid elongation, deltoid moment arm, joint stability and impingement-free range of motion) were evaluated for each motion. The framework took anatomical variability into consideration by performing the simulations using a subject-specific reverse shoulder cohort. Further, 36 modified configurations of the prosthesis (based on offsets to the placement of glenosphere, humeral tray and greater tuberosity) were evaluated. The effect of each of these modifiable parameters on the outcome measures was characterised as beneficial, detrimental, or negligible, in comparison to a default prosthesis configuration. Seven of the most beneficial parameters were then selected for combination and evaluated using the assessment framework. Due to an antagonistic relationship between the outcome measures, and differing functional requirements of the motions, none of the configurations were able to simultaneously maximise all outcome measures. Rather, the optimised configuration (which inferiorly translated the glenosphere and posteromedially translated the humeral tray) provided balanced, moderate improvements to majority of the outcome measures. Overall, the deltoid did not excessively elongate, and deltoid moment arms, joint stability, and impingement-free range of motion improved by 17.9%, 57.1%, and 32.1%, respectively compared to the default configuration. Subsequently, comparisons between the effect of the default and optimised configurations on muscle fatigue and micromotion at the bone-implant interface were made. Muscle fatigue was assessed by adapting the NSM, and micromotion was assessed through a finite element analysis of a subset of the reverse shoulder cohort. The optimised configuration had a beneficial impact on the time to initiate muscle fatigue by decreasing the force required by the middle deltoid to initially elevate the humerus, and it had no appreciable effect on micromotion. In summary, an optimised RTSA configuration has been presented in this thesis. For a rotator cuff deficient reverse shoulder, the proposed configuration provided balanced, moderate improvements to majority of the functional outcomes. Additionally, the configuration was able to mitigate the effect of muscle fatigue and did not affect micromotion. Future studies should look to experimentally validate these findings, determine their clinical significance, and enhance both the assessment techniques and framework.
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Chen, An. "Buffer-efficient RTA algorithms in optical TDM networks /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?ECED%202007%20CHENA.
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Fiala, Petr. "Modelování procesu projekčního a projekčně-rekonstrukčního rtg zobrazení." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218665.
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The work deals with physical principles of X-ray generation and development of image during projection and projection reconstruction. A proposal of user’s application in a Matlab – Guide is given, which can be used as a laboratory exercise of the simulation of the projection- and projection image reconstruction. The computer program involves an evaluation of a X-ray quality of CT RTG ZS – quantitative assessment of spatial resolution and as well as the acquisition contrast as a function on an object size. The main aim of the work was the comparison of the acquisition contrast at various acquisition projection and projection-reconstruction parameters. Also, the work is illustrated by some results achieved.
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Stalnikiewicz, Bertrand. "Le traitement des embolies pulmonaires graves par activateur tissulaire du plasminogene rtpa." Lille 2, 1991. http://www.theses.fr/1991LIL2M307.
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Chaves, Elton Jose Ferreira. "Simulação molecular de inibidores da subunidade da ricina, RTA." Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/9691.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Ricinus communis, specifically fruit, castor bean, has gained industry, media and government attention due to the derivate properties such as ricin and castor oil. The total fatty acids xtracted from castor bean, 90% comprises ricinoleic acid. Beyond the castor oil, castor bean processing generate co-products: fruit peel and the castor cake. These co-products present significant amounts of fibers and proteins, in addition to a potential use as nematicide. Since world production of castor oil is 1.5 million tons per year and the proportion of co-product production with castor oil production is approximately 1:1, so, it’s essential to find an economically viable destination for these co-products. In addition to the destinations used, a route with high commercial value would be the use as animal feed, however, this does not occur due to the presence of ricin. Ricin its a ribosome inactivating protein present in the castor bean seed, that consists of two subunits, RTA and RTB, with the RTA being the catalytic subunit. In addition this problem, ricin is used as a biological weapon by terrorists and activists. The inhibition of mechanism of ricin action has biotechnological interest, where RTA is the target for inhibitors synthesis. In this context, the method used to search for new inhibitors its Molecular Docking. This method evaluates thousands of ligands in a short time, however, presents low accuracy in the prediction of binding affinity. In this perspective, SMD simulations can be used. This method is based on the correlation of the mean force profile needed to decouple the ligand from the protein with its affinity. The scientific literature has reported promising results with the approach to discern active binders from inactive. In the present study, beyond the validation data from known RTA inhibitors, the binding affinity potential of 6 novel structures to form complexes with RTA using SMD simulations was evaluated. It was necessary to use Molecular Docking and Molecular Dynamics aproaches to obtain and refine new RTA complexes with novel ligands and next submitted to SMD simulation (k = 2 kcal/mol/Ų, v = 0.005 nm/ps). In addition to the mean force profile obtained from multiple independent SMD simulations, the rupture force and the average of pulling work were measured, these being a direct relation with the binding affinity. In summary, the results of the validation of rupture force and average of pulling work with the experimental data showed a correlation and determination coefficient with R = -0.992 and R² = 0.984 (rupture force) and R -0.958 and R² = 0.918 (average of pulling work), respectively. By means of these validations, the evaluation of novel structures using SMD simulations showed that 4 of the 6 proposed structures present in silico, binding affinity potential for RTA.
A Ricinus communis, especificamente o seu fruto, a mamona, tem ganhado atenção da indústria, mídia e governos, devido as propriedades de seus derivados, especialmente a ricina e o óleo. Do total de ácidos graxos extraídos da mamona, 90% compreende ao ácido ricinoleico. Além do óleo, os coprodutos gerados durante a produção tem ganhado bastante atenção, sendo os mais importantes, a casca do fruto e a torta. Tais coprodutos apresentam quantidades significativas de fibras e proteínas, além de um potencial uso como nematicida. Uma vez que a produção mundial de óleo de mamona é de 1,5 milhão de toneladas-ano e a proporção de produção de coprodutos com a produção de óleo é de aproximadamente 1:1, é fundamental encontrar um destino economicamente viável para esses coprodutos. Além dos destinos utilizados, uma rota com alto valor comercial seria o uso como ração animal, entretanto, isto não ocorre devido a presença da ricina. Esta, corresponde a uma proteína inativadora de ribossomos presente na semente da mamona, e é constituída por duas subunidades, a RTA e RTB, sendo a RTA a subunidade catalítica. Além da problemática supracitada, a ricina é utilizada como arma biológica por terroristas e ativistas, logo, a inibição do mecanismo de ação desta proteína é de grande interesse biotecnológico, sendo a RTA o alvo para síntese de inibidores. Neste aspecto, o método utilizado para busca de novos inibidores é o Atracamento Molecular (Molecular Docking). Este método avalia milhares de ligantes num curto intervalo de tempo, entretanto, apresenta baixa acurácia na predição da afinidade de ligação. Nesta perspectiva, a Dinâmica Molecular Induzida (SMD), pode ser utilizada. Este método baseia-se na correlação do perfil de força médio necessário para desacoplar o ligante da proteína com a sua afinidade. A literatura científica tem relatado resultados promissores no uso dessa abordagem para discernir ligantes ativos de inativos. No presente estudo, além de validações com inibidores de RTA conhecidos, foi avaliado o potencial de afinidade de 6 estruturas inéditas a formarem complexos com a RTA utilizando simulações SMD. Para isso, foi necessário recorrer a abordagens de Atracamento Molecular e Dinâmica Molecular para obtenção e refinamento de novos complexos da RTA com os ligantes candidatos, para somente então, serem submetidos a simulação SMD (k = 2 kcal/mol/Ų, v = 0.005 nm/ps). Neste passo, além do perfil de força médio obtido a partir de múltiplas simulações SMD independentes, foi mensurado a força de ruptura e o trabalho médio realizado pela força, este último, apresenta uma relação direta com a afinidade de ligação pela igualdade de Jarzynski. Em suma, resultados de validação da força de ruptura e trabalho com os dados experimentais mostraram coeficiente de correlação e determinação com R = -0.992 e R² = 0.984 (força de ruptura) e R -0.958 e R² = 0.918 (perfil médio do trabalho), respectivamente. Por meio destas validações, a avaliação dos ligantes candidatos utilizando simulações SMD mostrou que 4 das 6 estruturas propostas, apresentam in silico, potencial de afinidade de ligação para com a RTA.
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Aarøe, Øyvind. "En sammenligning av RTA og CTA: : testsituasjonens innvirkning på resultatet." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10320.
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CTA har vært utsatt for sterkt kritikk av eksperter. Dette er kritikk som spesielt fokuserer på metodens validitet og gjennomførelse. Denne masteroppgaven fokuserer på brukbarhetstester med et annet perspektiv; brukernes opplevelse av metoden. Oppgaven prøver finne ut om, og eventuelt i hvor stor grad, testsituasjonen påvirker testresultatene. I dette studiet gjennomføres til sammen 20 brukbarhetstester. Testene ble gjennomført i to runder på et nettsted for Studentsamskipnaden i Trondheim". Studiet viser at RTA og CTA oppleves forskjellig av testbrukerne, og at opplevelsen av CTA har innvirkning på resultatene. CTA- testdeltagerne brukte lengre tid på å gjennomføre oppgavene og metoden avdekket i tillegg falske brukskvalitetsproblem. Alle testdeltagerne kom med flere negative tilbakemeldinger på CTA, mens det stort sett var positive tilbakemeldinger på RTA metoden. Den negative kritikken av CTA var gjennomgående temaer som; mislikte å bli filmet, dobbel kognitiv belasting, vanskelig å sette ord på tanker, prestasjonsangst, press til å snakke, dårlig tid til oppgaveløsning, vanskelig å holde verbaliseringen gående og tenker annerledes enn de snakker.
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Cavarsan, Fabio Aparecido. "Processos termicos rapidos RTO / RTA para fabricação de dispositivos MOS." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259289.
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Orientador: Jose Alexandre DinizDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Mestrado
Microeletronica e Optoeletronica
Mestre em Engenharia Elétrica
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Wegrzyn, Margaret. "Sodium potassium niobate based piezoelectric ceramics." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/sodium-potassium-niobate-based-piezoelectric-ceramics(8f2d3804-5012-4562-8bb0-2b325b754d13).html.
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NKN doped samples, (100-x)NKN-xSBN (0 ≤ x ≤ 10) were produced using the conventional mixed oxide route with 0.45 wt% Fe2O3 sintering aid (xSBNF). After 20-24 hours mixing, samples were calcined at 850°C and sintered at 1100–1140°C (± 180°C/hour) for 4 hours. By XRD 4 mol% SBN was found to be the solubility limit for single phase structure. By SEM, second phases were visible when 2 ≤ x ≤ 4; their structure was subsequently shown to be tungsten bronze type (TBT). 2-4 SBNF samples were high density, over 96% theoretical. For x = 0, TC = 457°C, TO-T = 234°C, Pr = 22 μC/cm2 and EC = 16.5 kV/cm. TC was found to decrease by 14.7°C and TO-T by 9.0°C per 1 mol% addition SBN. 2SBNF was the optimal formulation in terms of microstructure and electrical properties, with average grain size 3 μm, Pr = 25 μC/cm2 and EC = 8.8 kV/cm, ρ = 4.7 kΩm and Q = 1.16 eV. This material comprised approximately 90% orthorhombic and 10% tetragonal phases coexisting. Pseudo-cubic lattice parameters are a’ = c’ = 3.947180 Å, and b’ = 3.999996 Å for orthorhombic phase; the tetragonal has a’ = c’ = 3.989798 Å, and b’ = 3.975777 Å.Synchrotron XRD studies were undertaken as a function of temperature on 99.5NKN-0.5CuO + 0.6 wt% Nb2O5 solid and powder samples. The data were Rietveld refined. The solid sample underwent two polymorphic phase transitions at 300°C and 515°C; the latter was between two tetragonal phases: lattice parameters for the tetragonal phase (300-520°C) were a’ = c’ = 4.99557 Å, and b’ = 4.0363 Å; high temperature tetragonal (>500°C) exhibited a’ = c’ = 4.9519 Å, and b’ = 4.4941 Å. The powder sample of the same formulation exhibited more, smaller transformations. It was only orthorhombic at temperatures <140°C with a’ = c’ = 4.10680 Å, and b’ = 4.02620 Å. Above 140°C both orthorhombic and tetragonal phases were present. Another significant transformation occurred at 360°C where the structural unit cell parameters changed significantly. Parameter lengths are provided. P-E data was characterised by Pr = 19.9 μC/cm2 and EC = 13.5 kV/cm. Synchrotron X-ray diffraction analysis of 94 NKN-6LiTaO3 showed that tetragonal phase was present at 20-390°C, although an orthorhombic phase was identified at 20-200°C and again at 340-390°C just before the cubic transition temperature at 390°C. This is a new observation for NKN. A new and simple method for tape casting was developed to reduce powder wastage, enabling thick films of 50 μm to be cast. The reactive templated grain growth (RTGG) method was employed to orient 95NKN-5LiNbO3 and 94NKN-6LiNbO3 samples; CuO was utilised as a sintering aid. Pre-cursor BNN and NN template particles were produced using the molten salt synthesis (MSS) method, using a salt to oxide ratio of 1:1. Resulting NN particles were 15 μm wide and 0.5 μm thick. Eight layered 6LN + 0.4 wt% tapes produced using 10 wt% template particles resulted in 210 μm thick tapes with 67% orientation when sintered at 1150°C. Resulting properties include TC = 440ºC and TO-T = 70ºC, 25 kΩ resistance and capacitance 21.6 pF.
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Torelli, Nicole Quesada. "Sinalização retrógrada RTG-dependente controla a atividade mitocondrial e resistência a estresse em Saccharomyces cerevisiae." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-25032015-115054/.
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A sinalização retrógrada mitocondrial é uma via de comunicação entre a mitocôndria e o núcleo que regula a expressão de uma série de genes nucleares que codificam proteínas mitocondriais, em resposta a disfunções mitocondriais. Em Saccharomyces cerevisiae, a via depende de Rtg1p e Rtg3p, que juntos formam o fator de transcrição que regula a expressão gênica, e de Rtg2p, um ativador da via. Aqui, nós mostramos novos estudos direcionados à investigação do impacto da sinalização retrógrada RTG-dependente na fisiologia mitocondrial. Verificamos que mutantes incapazes de realizar sinalização retrógrada RTG-dependente apresentam consumo de oxigênio mais elevado e menor produção de peróxido de hidrogênio em fase estacionária quando comparados a células selvagens. Interessantemente, mutantes RTG são menos capazes de decompor peróxido de hidrogênio assim como manter-se viáveis quando desafiados com peróxido. Nossos resultados indicam que a sinalização por RTG está envolvida na indução hormética de defesas antioxidantes e de resistência a estresse, função ainda não descrita para este sistema.Mitochondrial retrograde signaling is a communication pathway between the mitochondrion and the nucleus which regulates the expression of a subset of nuclear genes that codify mitochondrial proteins, mediating cell response to mitochondrial dysfunction. In Saccharomyces cerevisiae, the pathway depends on Rtg1p and Rtg3p, which together form the transcription factor that regulates gene expression, and Rtg2p, an activator of the pathway. Here, we provide novel studies aimed at assessing the functional impact of the lack of RTG-dependent signaling on mitochondrial activity. We show that mutants defective in RTG-dependent retrograde signaling present higher oxygen consumption and reduced hydrogen peroxide release in the stationary phase when compared to wild type cells. Interestingly, RTG mutants are less able to decompose hydrogen peroxide as well as maintain viability when challenged with hydrogen peroxide. Overall, our results indicate that RTG signaling is involved in the hormetic induction of antioxidant defenses and stress resistance, a function of this system not yet described.
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Klekner, Martin. "Aplikace analytických metod využívajících RTG záření v oblasti analýz stavebních materiálů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225574.
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Master’s thesis mainly deals with XRF analysis of building materials. Comprehensively analyzes the factors that limit the accuracy of the obtained data, creates a new methodology for the rapid analysis of silicate materials by XRF instrument and discusses the influences determining the reproducibility of the results of XRF analysis.
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Stejkora, Jakub. "Analýza rentgenových difraktogramů organických krystalických látek." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216745.
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Derivates of diketopyrrolopyrrole are colored pigments with potential use in field of organic semiconductor structures. Their electrical attributes such as conductivity, photocon¬¬ductivity and electroluminescence relate to their crystal structures that determine charge transport path through the compound. For crystallographic structure determination from RTG diffractometry it is needed to grow a measurable single crystal. Growing crystals of derivates of diketopyrrolopyrrols is very difficult due to their poor solubility in all solvents. Several relatively suitable – perhaps even measurable – samples were obtained throughout the testing of series of methods. One of these samples was measured with RTG diffractometry and on the ground of this measurement it was possible to find and solve the crystallographic structure.
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Pichler, Matthias. "Zelluläre Verteilung und Einfluss von rtPA und Hypothermie auf die Calpainaktivität bei zerebraler Ischämie/Reperfusion." Diss., lmu, 2006. http://nbn-resolving.de/urn:nbn:de:bvb:19-49988.
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Gautier-Morel, Sophie. "Complications hémorragiques induites au cours de la fibrinolyse par rtPA : mécanismes physiopathologiques et approches pharmacologiques." Lille 2, 2005. http://www.theses.fr/2005LIL2S005.
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Le mécanisme des complications hémorragiques cérébrales induites lors de l’utilisation du rtPA, activateur du plasminogène dans les accidents ischémiques cérébraux, est mal élucidé. En utilisant un modèle d’ischémie cérébrale par occlusion intraluminale de l’artère cérébrale moyenne, notre objectif a été d’étudier l’implication du thrombus, de la paroi vasculaire et de l’ischémie dans la physiopathologie de ces complications. Dans un deuxième temps, les potentielles cibles pharmacologiques pour leur prévention ont été étudiées. Nos données suggèrent que le traitement par rtPA conduit à la survenue de complications hémorragiques, et que la présence de produits de thrombolyse, en particulier de plasmine, majore la sévérité de ces complications, en parallèle d’une augmentation du volume d’infarctus, d’une majoration des altérations de la fonction endothéliale vasculaire et d’une augmentation dela perméabilité de la barrière hémato-encéphalique. Cette modification de la perméabilité est associée à une modification de l’expression des metalloproteases, enzymes impliquées dans la dégradation de la matrice extracellulaire des vaisseaux, et conduit à une modification de l’infiltration des polynucléaires neutrophiles. En ce qui concerne les cibles pharmacologiques potentielles, deux voies ont été explorées : (i) l’induction d’une neutropénie par la vinblastine prévient les altérations endothéliales vasculaires post-ischémiques et protége de la survenue des complications hémorragiques de la fibrinolyse en association avec une diminution du volume d’infarctus (ii) le fénofibrate, agoniste des récepteurs PPARs, protège des altérations endothéliales vasculaires post-ischémiques, en parallèle d’une diminution des lésions ischémiques et d’une diminution de l’apparition des complications hémorragiques. En conclusion, la protection du vaisseau lors de la fibrinolyse semble être une cible pharmacologique pertinente pour prévenir le risque de complicationshémorragiques induites par le rtPAThe use of rtPA (tissue-plasminogen recombinant activator) in stroke is associated with a risk of cerebral hemorrhagic complications, whom physiopathological mechanisms are not fully elucidated. Using a model of cerebral ischaemia by middle cerebral artery occlusion (MCAO), our objective was to firstly study the respective implication of thrombus, vascular wall and ischaemia in the physiopathology of rtPA-induced hemorrhages. Secondly, potential pharmacological targets for their prevention were studied. Our data confirmed that the treatment by rtPA led to hemorrhagic complications and suggested the role of thrombolysis products, in particular of plasmine, in the severity of these complications. In parallel, we observed an increase in the infarct volume, an increase in the vascular endothelial post-ischemic alterations and an increase in the blood-brain barrier (BBB) permeability. Th e modification of the BBB permeability was associated with an activation of metalloproteinase-9, enzyme implied in the matrix extracellular degradation, and contributed to the polymorphonuclear infiltration. Concerning the potential pharmacological targets, two pathways were explored : (i) the induction of a neutropenia by vinblastine prevented from post-ischaemic vascular alterations and limited the risk of rtPA-induced hemorrhagic complications in parallel to a reduction in the infarct volume (ii) the use of fenofibrate, agonist of the PPAR alpha receptors, protected from post-iscaemic vascular alterations in parallel with a reduction in the ischaemic lesions. Preliminary results suggested that the use of fenofibrate was also associated with a reduction of rtPA-induced hemorrhagic complications. In conclusion, the protection of vessels during the fibrinolysis seems to be a relevant pharmacological target to prevent the risk of rtPA-induced hemorrhagic complications
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Lindskog, Viktor. "Teoretiska och praktiska studier av kodtäckningsverktyg med utvärdering." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Data- och elektroteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-23665.
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Yang, Celeste. "A study of the calibration-inverse prediction problem in a mixed model setting." Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/1079.
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Heinrup, Rebecka. "Evaluation of isobutanol tolerance and gene expression in four different Saccharomyces cerevisiae strains for the development of bio-butanol production." Thesis, Linköpings universitet, Biologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-132314.
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Today, most transportation fuels are derived from crude oil. However, fossil fuels are limited resources and contribute to climate change, and are therefore not considered as sustainable. Biofuels are highly relevant candidates for replacing fossil fuels and research has gone into butanol as a biofuel. It has a high energy density, is less hygroscopic and can be blended up to 85% with gasoline. The yeast Saccharomyces cerevisiae is considered a good host for bio- butanol production; it produces small amounts of isobutanol naturally through the Ehrlich pathway, is easy to manipulate genetically and can therefore be engineered to produce higher titres of butanol. End-product toxicity, however, is a problem that needs to be solved to make butanol production in S. cerevisiae more effective, since the organism cannot tolerate higher concentrations of butanol than 2%. Four different S. cerevisiae strains were cultivated in 1.5%, 2%, 3% and 4% isobutanol by spot tests and in liquid media to evaluate their tolerance. Gene expression was measured for genes RPN4, RTG1 and ILV2 to examine their up-regulation and relevance in butanol tolerance. S. cerevisiae strain Saflager 34/70 was determined as the most tolerant strain and was able to grow in 2% liquid isobutanol and 3% isobutanol on agar plates. A three-fold up-regulation of RPN4, a transcription factor involved in the regulation of proteasome gene expression, was observed. These results contribute to the progress of genetic engineering of butanol host organisms, which is needed to create a more effective production of butanol as a biofuel.
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Gould, Faye. "Kaposi's Sarcoma-Associated Herpesvirus RTA Promotes Degradation of Cellular bHLH Transcription Factors." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515337.
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Lautier, Dominique. "Application de la microspectrofluorimétrie à l'étude intracellulaire des oxydases à fonction mixte dans les cellules RTG2." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37607093w.
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Lautier, Dominique. "Application de la microspectrofluorimétrie à l'étude intracellulaire des oxydases à fonction mixte dans les cellules RTG2." Montpellier 2, 1987. http://www.theses.fr/1987MON20202.
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La microspectrofluorimetrie appliquee a l'etude de la detoxication dans les cellules rtg2 permet de mesurer plusieurs etapes successives du mecanisme, en particulier grace a l'accumulation intracellulaire de metabolites fluorescents du benzo(a)pyrene(b(a)p) utilise comme marqueur de l'activite des monooxygenases (mfo). Trois hypotheses sont successivement envisagees pour expliquer la variabilite de cette activite: 1) existence des systemes enzymatiques differents; 2) existence de plusieurs isoenzymes du cytochrome p-450; 3) variabilite de la disponibilite en cosubstrat endogene. Cette etude revele que le 6-aminochrysene, signale comme un substrat des mfo, est en fait un substrat preferentiel des glucuronyl-transferases dans les cellules rtg2 et peut etre utilise comme inhibiteur de cette activite enzymatique
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Cartonnet, Adrien. "Contribution à l’étude du rejet à l’environnement de l’iode radioactif lors d’une séquence accidentelle de type RTGV." Thesis, Lille 1, 2013. http://www.theses.fr/2013LIL10123/document.
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Dans une séquence accidentelle de rupture de tube(s) de générateur de vapeur d’un réacteur à eau pressurisée (séquence RTGV), une fraction des espèces radioactives présentes dans le circuit primaire est susceptible d’être transférée à l’environnement. Parmi ces espèces, on porte une attention particulière à l’iode qui est le plus dangereux à court terme pour les populations et susceptible de former des espèces volatiles. En fonctionnement normal, le circuit primaire est contaminé par des produits de fission radioactifs à cause de micro fissures qui se développent dans les gaines des crayons combustible.Pour mieux estimer les rejets en cas de RTGV, il est primordial de déterminer la répartition des espèces iodées entre la phase gazeuse et la phase liquide en aval de la brèche ainsi que la granulométrie des gouttes générées (fraction transférée au secondaire) lors du flashing. La première partie de l’étude concerne la modélisation du jet diphasique généré à la brèche. Ainsi, un modèle physique a été développé dans le but de calculer la fraction vaporisée en champ proche ainsi que la distribution des gouttes (granulométrie) générée en sortie de brèche. Ce modèle a ensuite été appliqué et validé sur des expériences disponibles dans la littérature (essais conduits à l’US/ NRC et à l’INERIS). Une seconde partie est consacrée à la modélisation de la spéciation chimique de l’iode dans le circuit primaire et à la détermination des coefficients de partage des espèces de l’iode (calculs de dynamique moléculaire). Enfin, ces modèles ont été intégrés dans le logiciel de simulation des accidents ASTEC pour calculer le rejet gazeux et liquide lors d’une séquence accidentelle type RTGVIn a Steam Generator Tube Rupture (SGTR) accident occurring to a pressurised nuclear water reactor, a fraction of the radioactive species present in the primary circuit is likely to be transferred to the environment. Particular attention is paid to iodine for two reasons; the first one it is well known that iodine is a high contributor to the dose at short term and in second, due to possible formation of volatile species, which could be largely sprayed in the environment. In normal operating conditions, the primary circuit is contaminated with some radioactive products flowing through micro-cracks existing in the fuel rod claddings. To better estimate the releases for SGTR sequence, it is crucial to determine the iodine partition between the gas and the liquid phase downstream the tube break as well as the droplet size distribution generated during the flashing. The first part of the PhD presents a heat and mass transfer model developed to predict the two-phase jet behaviour at the break. The steam fraction is calculated as well as the droplet size distribution upstream the break. Experiments available in the literature (tests conducted at the U.S/NRC and INERIS) are used to validate the model. The second part concerns the modelling of the iodine chemical speciation in the primary conditions (irradiation, low concentration and presence of impurities). For each iodine species, the partition coefficient has been determined either in using literature data or with the help of molecular dynamics computations. Last, this global release modelling has been implemented in ASTEC, the IRSN accident simulation software and the releases have been calculated for one SGTR scenario
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Lesch, Christian Manfred. "Grain refinement of cold rolled low carbon steels by rapid transformation annealing (RTA) /." Aachen : Shaker, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=014915691&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Wood, Jennifer Jane. "The effect of Kaposi's sarcoma-associated herpesvirus RTA expression upon the cellular proteome." Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/6344/.
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Kaposi’s sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi’s sarcoma (KS). Like all herpesviruses, KSHV has a bi-phasic life cycle, with a dormant latent phase and a productive lytic phase. The switch from viral latency to lytic replication is mediated by the replication and transcription activator protein (RTA). RTA activates KSHV lytic gene expression via direct and indirect binding to lytic promoters. Moreover, it functions as an E3 ubiquitin ligase, actively degrading repressor proteins, such as Hey1, maintaining the virus in the latent state. The first aim of this study was to determine if RTA functions as a SUMOylation targeted ubiquitin ligase (STUbL), which recognises poly-SUMOylated targets via SUMO interacting motifs (SIMs). Results presented herein demonstrate that the Hey1 repressor protein is SUMO2 modified. Furthermore, mutation of SIM domains within RTA resulted in attenuation of RTA-mediated degradation of Hey1 and lytic reactivation. However, SIM mutation also severely reduced RTA-mediated transactivation. These results suggest that RTA may have STUbL activity but additional work is required to reconcile the effect of SIM mutation upon transcriptional activity. The second aim of this investigation was to identify novel points of interaction between RTA and the host cell. In chapter 4, SILAC-based quantitative proteomics identified hundreds of proteins which demonstrated a significant change in abundance upon RTA expression. Abundance of the cellular protein ARID3B was found to increase over 7-fold in the nuclear fraction. Furthermore, ARID3B was shown to re-localise to viral replication centres upon lytic reactivation. In chapter 5 SILAC-based immunoprecipitations were performed to identify novel RTA interaction partners. The cellular co-activator RBM14 was found to be enriched in two independent SILAC data sets and subsequent investigation demonstrated that RBM14 localisation was altered upon RTA expression. These novel observations highlight the potential significance of cellular factors in KSHV infection. Further investigation is required to fully characterise the role of these proteins in viral reactivation.
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Varma, Sreejith Jayasree. "Mimicking C-C bond forming reactions of core metabolism." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF038/document.
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Toutes les formes de vie assemblent et désassemblent continuellement des composés chimiques via un processus de consommation d'énergie appelé métabolisme. Le métabolisme est généralement modélisé en chimie et biologie par un cycle. Ce modèle dynamique traduit la transformation de composés de base en une cascade de produits appelés métabolites. Celui-ci est comparable à un ouragan à l’échelle moléculaire. De manière analogique et imagée un cyclone est constitué de deux éléments, l'air et l'eau, et transforme l’environnement qui l’entoure par un processus endothermique (consommateur d’énergie). Traditionnellement, la recherche chimique sur les origines de la vie est concentrée principalement sur la synthèse de composés chimiques sans suffisamment apprécier leur place dans la plus grande organisation biochimique de la vie. La vie construit toutes ses molécules à partir du dioxyde de carbone, pourtant elle manque étonnamment d'innovation à cet égard. Malgré presque 4 milliards d'années d'évolution, les organismes autotrophes utilisent seulement six voies différentes pour construire leurs molécules à partir du CO2. Parmi elles, deux voies – la voie de l’acétyle CoA (aussi appelée voie Wood-Ljungdahl) et le cycle du rTCA (également appelé le cycle de Krebs inverse) - sont considérées comme primitives, et contiennent les cinq molécules servant de précurseurs chimiques universels pour toute la biochimie. Comment et pourquoi les voies de l’acétyle CoA et du rTCA sont-elles apparues? Pour répondre à cette question, une recherche systématique a été effectuée afin de trouver des catalyseurs chimiques non-enzymatiques ou des minéraux simples, ainsi que des réactifs pouvant promouvoir les réactions d'anabolisme principal, particulièrement la voie de l’Acétyle CoA et le cycle de rTCA. A l’origine, pour créer les molécules organiques complexes comme les enzymes il a fallu que des molécules plus simples avec un moins grand nombre de carbone se forme sur terre et cela à partir du CO2. On peut donc supposer que les premiers produits à plusieurs carbones sont issus de synthèse totalement inorganique comme celles développer dans notre laboratoire, plutôt que d’une évolution chimique et organométallique simultanée, c’est-à-dire une interaction efficace entre une molécule carbonée et un ou plusieurs métaux à l’instar de certains enzymes. Après avoir trouvé autant de façons possible de promouvoir individuellement chaque étapes des cycles catalytiques étudiés, seules les conditions réactionnelles mutuellement compatibles (à savoir des conditions permettant de produire l’ensemble des métabolites dans le bon ordre) ont été retenuAll life forms continuously build up and break down its constituent chemical building blocks, through an energy consuming process called metabolism. Just like a hurricane’s dynamic patterns and its building blocks (air and water) as being equally fundamental to its nature, so too should metabolism’s dynamic chemical patterns and chemical building blocks be viewed as equally characteristic. Traditionally, much chemical research on the origins of life is overly focused on the synthesis of chemical building blocks without sufficiently appreciating their place in life’s larger biochemical self-organization. Life ultimately builds all of its molecules from carbon dioxide, yet it is surprisingly lacking in innovation in this respect. Despite nearly 4 billion years of evolution, autotrophic organisms use only six pathways to build their molecules from CO2. Two of these pathways – the acetyl CoA pathway (also known as the Wood-Ljungdahl pathway) and rTCA cycle (also known as the reverse Krebs cycle) - are thought to be ancestral, with just five molecules within them serving as the universal chemical precursors for all of biochemistry. How and why did these pathways get their start? To answer this question, a systematic search was designed to find simple, non-enzymatic chemical or mineral catalysts and reagents, that can promote the reactions of core anabolism, particularly the acetyl CoA pathway and the rTCA cycle. After finding as many ways as possible to promote each reaction, they could be narrowed down to mutually compatible conditions where many reactions can occur in sequence. The more of core anabolism that can be achieved under a single set of purely chemical conditions, the more likely it is to have constituted early prebiotic chemistry rather than a later product of chemical and biological evolution
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Davenport, Bradley P. "Advanced thermophotovoltaic cells modeling, optimized for use in rRadioisotope Thermoelectric Generators (RTGS) for Mars and deep space missions /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Jun%5FDavenport.pdf.
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Davenport, Bradley P. "Advanced thermophotovoltaic cells modeling, optimized for use in radioisotope thermoelectric generators (RTGS) for Mars and deep space missions." Thesis, Monterey California. Naval Postgraduate School, 2004. http://hdl.handle.net/10945/1170.
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Approved for public release; distribution is unlimited.Thermophotovoltaic cells are a good candidate for use in high efficiency radioisotope thermoelectric generator (RTG) power devices for deep space missions. This thesis examines the use of Silvaco Virtual Wafer Fabrication Software as a tool for designing and optimizing TPV cells for different possible spectra. It gives results for GaSb and InGaAs cells optimized to the AM0 spectrum which closely match published data as well as hypothetical cells optimized to the spectrum of a 1300K blackbody.
Ensign, United States Navy
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Schriefer, Philipp [Verfasser], and Jörg [Akademischer Betreuer] Petersen. "Quantitative Bestimmung der relativen Telomeraseaktivität (RTA) in malignem Lebergewebe / Philipp Schriefer. Betreuer: Jörg Petersen." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2011. http://d-nb.info/102041779X/34.
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Zaniquelli, Osvaldo. "Desenvolvimento de uma membrana alternativa, nao reabsorvivel, para uso em regeneração tecidual guiada (RTG)." [s.n.], 1996. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290098.
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Orientador: Simonides ConsaniTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-07-21T02:40:17Z (GMT). No. of bitstreams: 1 Zaniquelli_Osvaldo_D.pdf: 2899568 bytes, checksum: a95083047ea9dc7c51753f2a93d9d095 (MD5) Previous issue date: 1996
Resumo: O trabalho objetivou o desenvolvimento de uma membrana alternativa, de baixo custo, para utilização na técnica de REGENERAÇÃO TECIDUAL GUIADA (RTG) em Periodontia. Para isso utilizou-se como substrato da mesma fibra entrelaçadas de celulose constituintes de papel filtro de uso comercial, com espessura de aproximadamente 200 'mu'm. Este substrato foi embebido com uma mistura de resina epóxica com material de carga constituido de 'CaCO IND. 3' e ZnO. Estes dois componentes foram balanceados na mistura para se atingir uma rigidez adequada para manutenção do espaço periodontal na técnica de RTG, baseados em sua curvas de distribuição granulométrica (CDG). A membrana resultante foi submetida aos ensaios de: I) avaliação quanto a sua característica de material inerte; II) resistência ao rasgamento com fio de sutura; III) flexibilidade em curvaturas de pequeno ângulo de dobradura; IV) espessura e V) rigidez. Foi concluído dentro da proposta do trabalho, que a membrana proposta possui: I) característica de material inerte,mesmo em situações onde a agressividade química é elevada; II) resistência ao rasgamento relativa aproximadamente duas vezes maior que a membrana comercial utilizada na comparação; III) resistência a ruptura na região de dobramento a pequenos diâmetros; IV) uma rigidez razoável para promover e manter o espaço periodontal exigido na recuperação óssea na técnica de RTG
Abstract: The development of an alternative low cost membrane for use in guided tissue regeneration (GTR) is presented. The membrane is prepared fiom a 200 'mu'm thick cellulose substrate, embedded in epoxy resin. The filler materiais 'CaCO POT. 3' and ZnO were used to attain the flexibility and rigidity necessary to keep the periodontal space. The inorganic formulation of the composite membrane was achieved fiom the analysis of the granulometric distribution curve. No liberation of inorganic or organic residues is detected. The membrane was also checked: for the resistance to tear, small angle bending flexibility, rigidity and thickness. In conclusion the developed material presents: I) the inert material features, even in situations of high aggressive chemical medium; II) the relative tear resistance twice higher that found for the commercial membrane used for comparison; III) the resistance to rupture in the small angle bending diameters and IV) the rigidity enough to keep the periodontal gap suitable for the bone regeneration using the GTR
Doutorado
Materiais Dentarios
Doutor em Odontologia
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Kim-Verjus, Kyung Sook. "Cristallisation de couches minces de silicium par recuit rapide RTA pour applications micro-électronique." Paris 7, 2001. http://www.theses.fr/2001PA077208.
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CARLIN, JEAN-LUC. "Efficacite et complications du protocole de thrombolyse rtpa faible dose - stk a la phase aigue de l'infarctus du myocarde." Aix-Marseille 2, 1992. http://www.theses.fr/1992AIX20162.
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Deeks, Emma Dawn. "The evasion of ubiquitin-mediated proteasomal degradation by RTA upon retrotranslocation across the ER membrane." Thesis, University of Warwick, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393045.
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Schlegel, Anna [Verfasser]. "Anlage von Lysekathetern zur rtPA- Lysetherapie von intrazerebralen Hämatomen : Führt die zentrale Lage des Lysekatheters zur effektiveren Hämatomlyse? / Anna Schlegel." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2021. http://d-nb.info/1233865730/34.
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Zhou, Ruixin. "SEMICONDUCTOR PHOTOCATALYSIS: MECHANISMS, PHOTOCATALYTIC PERFORMANCES AND LIFETIME OF REDOX CARRIERS." UKnowledge, 2017. http://uknowledge.uky.edu/chemistry_etds/85.
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Photocatalytic reactions mediated by semiconductors such as ZnS, TiO2, ZnO, etc. can harvest solar energy into chemical bonds, a process with important prebiotic and environmental chemistry applications. The recycling of CO2 into organic molecules (e.g., formate, methane, and methanol) facilitated by irradiated semiconductors such as colloidal ZnS nanoparticles has been demonstrated. ZnS can also drive prebiotic reactions from the reductive tricarboxylic acid (rTCA) cycle such as the reduction of fumarate to succinate. However, the mechanism of photoreduction by ZnS of the previous reaction has not been understood. Thus, this thesis reports the mechanisms for heterogeneous photocatalytic reductions on ZnS for two model reactions in water with sulfide hole scavenger. First the reduction of CO2 is carried out under variable wavelength of irradiation and proposed to proceed thorough five steps resulting in the exclusive formation of formate. Second the reduction of the double bond of fumaric acid to succinic acid is reported in detail and compared to the previous conversion of CO2 to formic acid. Both reactions are carried out under variable wavelength of irradiation and proposed to proceed thorough one electron transfer at a time. In addition, a new method to measure the bandgap of colloidal ZnS suspended in water is established. Furthermore, the time scales of electron transfer and oxidizing hole loss during irradiation of ZnS for both reactions are reported and interpreted in terms of the Butler-Volmer equation.
The sunlight promoted production of succinate introduced above, provides a connection of this prebiotic chemistry work to explore if central metabolites of the rTCA cycle can catalyze the synthesis of clay minerals. Clay minerals are strong adsorbents that can retain water and polar organic molecules, which facilitate the polymerization of biomolecules and conversion of fatty acid micelles into vesicles under prebiotic conditions relevant to the early Earth. While typical clay formation requires high temperatures and pressures, this process is hypothesized herein to be accelerated by central metabolites. A series of synthesis are designed to last only 20 hours to study the crystallization of sauconite, an Al- and Zn-rich model clay, at low temperature and ambient pressure in the presence of succinate as a catalyst. Succinate promotes the formation of the trioctahedral 2:1 layer silicate at ≥ 75 °C, 6.5 ≤ pH ≤ 14, [succinate] ≥ 0.01 M. Cryogenic and conventional transmission electron microscopies, X-ray diffraction, diffuse reflectance Fourier transformed infrared spectroscopy, and measurements of total surface area and cation exchange capacity are used to study the time evolution during the synthesis of sauconite.
While the studies with ZnS presented above advanced the fundamental understanding of photocatalysis with single semiconductors, the environmental applications of this material appear limited. A common limitation to photocatalysis with single semiconductors is the rapid recombination of photogenerated electron-hole pairs, which reduces significantly the efficiency of the process that in the case of ZnS also suffers from photocorrosion in the presence of air. In order to overcome the fast charge recombination and the limited visible-light absorption of semiconductor photocatalysts, an effective strategy is developed in this work by combining two semiconductors into a nanocomposite. This nanocomposite is solvothermally synthesized creating octahedral cuprous oxide covered with titanium dioxide nanoparticles (Cu2O/TiO2). The nanocomposite exhibits unique surface modifications that provide a heterojunction with a direct Z-scheme for optimal CO2 reduction. The band structure of the nanocomposite is characterized by diffused reflectance UV-visible spectroscopy, X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy. The photoreduction of CO2(g) to CO(g) on the nanocomposite is investigated in the presence water vapor as the hole scavenger that generates the quantifiable hydroxyl radical (). The quantum efficiency of CO production under irradiation at λ ≥ 305 nm with the nanocomposite is 2-times larger than for pure Cu2O. The detection of and XPS analysis contrasting the stability of Cu2O/TiO2 vs Cu2O during irradiation prove that TiO2 prevents the photocorrosion of Cu2O.
Overall, the studies of photocatalytic reductions on single component semiconductors reveal new knowledge needed for developing future photocatalytic application for fuel production, wastewater treatment, reducing air pollution, and driving important prebiotic chemistry reactions. Furthermore, the design of a photocatalyst operating under a Z-scheme mechanism provides a new proof of concept for the design of systems that mimic photosynthesis. Finally, this work also demonstrates how molecules obtained by mineral mediated photochemistry can catalyze clay formation; highlighting the important role that photochemistry may have played for the origin of life on the early Earth and other rocky planets.
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Lesch, Christian M. [Verfasser]. "Grain Refinement of Cold Rolled Low Carbon Steels by Rapid Transformation Annealing (RTA) / Christian M Lesch." Aachen : Shaker, 2006. http://d-nb.info/1170532543/34.
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Puls, Svenja [Verfasser]. "Experimentelle Untersuchung zur Ko-Applikation von recombinant tissue Plasminogen Activator (rtPA) und Bevacizumab bei neovaskulärer AMD mit submakulärer Blutung / Svenja Puls." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1142154726/34.
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"The Rtg1 and Rtg3 proteins are novel transcription factors regulated by the yeast hog1 mapk upon osmotic stress." Universitat Pompeu Fabra, 2009. http://www.tesisenxarxa.net/TDX-0714109-102158/.
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Horák, Lukáš. "Studium stuktury kovových polykrystalických vrstev rtg difrakcí a rtg reflexí." Master's thesis, 2006. http://www.nusl.cz/ntk/nusl-270193.
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Gojiš, Ondřej. "Fokální infekce a RTG." Master's thesis, 2006. http://www.nusl.cz/ntk/nusl-272142.
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Focal infection is much debated and denounced topic. Currently, during development diagnostic and therapeutic methods are again coming to the fore. Effect of remote tissues and organs infectious inflammation can occur in three ways, and metastatic infections metastatic inflammation, and metastatic hepatic. The most common diseases of the tissues of the oral cavity the consequences of long-term persistence of bacteria / carious destruction of teeth, chronic periodontitis and chronic inflammation of the periodontal /.
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Valeš, Václav. "Vysokoteplotní RTG difraktometrie tenkých vrstev." Doctoral thesis, 2015. http://www.nusl.cz/ntk/nusl-334635.
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In this work, the crystallographic structure and its changes under thermal treatment of different systems consisting of metal oxide nanoparticles is studied. The principal method used throughout the thesis is x-ray powder diffraction enriched with grazing incidence small angle x-ray scattering when the nanoparticles form an ordered structure or with x-ray absorption spectroscopy when additional information on local crystallographic structure is required. For all the systems the preparation conditions were optimized according to the crystallographic data for further applications.
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-YU, LIN SHIANG, and 林鄉宇. "1.Expression and purification of GST-Rta fusion proteins 2.Cell cycle analysis of Rta transfected cells." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/67019281788030436500.
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碩士國立臺灣大學
微生物學研究所
90
The Epstein-Barr virus (EBV) immediate-early gene BRLF1 encodes a transcriptional activator, Rta , that mediates the switch from latency to lytic viral replication. Rta interacts with trascriptional activators TBP、TFIIB and CBP. The interaction between Rta and CBP promotes transactivation ability of Rta. Rta also binds the tumor suppressor protein Rb, which controls entry into G1/S in the cell cycle. Therefore, it is possible that Rta may interact with other cellular factors to exert its transtriptional activation ability. While EBV latency-associated gene products facilitate G1/S progression, lytic gene expression elicits cell cycle arrest. Another EBV immediate-early protein Zta is found to mediate G0/G1 cell cycle arrest through induction of cyclin-dependent kinase inhibitors. Rta, like Zta, may regulate cell cycle to promote lytic cycle progression. The first part of this thesis intended to express GST-Rta deletion mutants for searching of additional cellular proteins that may also interact with Rta. However, purification of these proteins is failed because of low expression levels. The second part of this thesis intended to study the effect of Rta on cell cycle progression. The results indicated that Rta caused G0/G1 arrest in HEp-2 cells、293 cells and HONE-1cells. Since the tumor suppressor p53 is the key regulator of growth arrest, it may play a role in Rta mediated G0/G1 arrest. Our results demonstrated that Rta indeed upregulated p53 protein level in HEp-2 cells and HONE-1 cells. In addition, the activation of p53 in HEp-2 cells was also demonstrated. These findings suggest that Rta stimulates p53 which is responsible for Go/G1 arrest in HEp-2 cells.
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Hsu, Hao Lung, and 許皓隆. "Controlled release of rtPA from water soluble chitosan magnetic nanoparticles." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/15304106773360379766.
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碩士長庚大學
化工與材料工程學系
100
In this study, Fe3O4 nanoparticles were first prepared by the co-precipitation method. Magnetic water soluble chitosan (WSC) nanoparticle (MCNP) containing recombinant tissue plasminogen activator (rtPA) was then prepared to develop an efficient magnetic targeted drug delivery system for the thrombolytic drug. rtPA was first adsorbed to Fe3O4 nanoparticle, followed by entrapment in a gel layer by ionic cross-linking of WSC and sodium tripolyphosphate. Experimental design based on central composite design was used to analyze the influence of variables during preparation on the encapsulation efficiency (EE) and loading efficiency (LE) of rtPA. Under the optimum condition, the EE was 80% with the LE is 20 %. The physico-chemical properties of MCNP were characterized by DLS, TEM, FTIR, SQUID, TGA, EDS, AFM, ICP, Zeta potential and XRD. MCNP was 300-350 nm in size and with a spherical shape. In vitro drug release studies showed a burst release in phosphate buffer saline with 80% drug release in 20 min and the relative specific activity of released drug was as high as 50%. The MCNP showed no cytotoxicity by MTT assay and no hemolysis effect in blood over a broad concentration rang up to 7.5 mg/ml. The enzyme activity of MCNP-rtPA could be fully preserved in 0.01M phosphate buffer up to 28 days. Conjugating polyethylene glycol to MCNP-rtPA did not influence EE and LE but decreased the drug release percentage to 60 %. For thrombolysis efficacy of MCNP-rtPA and MCNP-PEG-rtPA, an ex vivo intravascular thrombolysis model showed similar potency compared to free rtPA. However, immobilized rtPA could restore the iliac blood flow in a rat embolic model, which was not possible with free rtPA with the same dosage. MCNP-rtPA and MCNP-PEG-rtPA are new forms of thrombolysis drug potentially useful for the treatment of thrombus.
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Lin, Yi-Chieh, and 林宜潔. "Effects of the truncated Rta mutants of Epstein-Barr virus on the biological function of wild-type Rta." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/60560201541259062266.
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碩士國立臺灣大學
微生物學研究所
92
Rta, encoded by Eptein-Barr virus (EBV) immediate early gene BRLF1, is a transcription activator that mediates the switch from latency to lytic viral replication through direct DNA binding or through cellular factors. Three major functional domains have been defined on the Rta protein, including an amino-terminal dimerization domain, a DNA binding domain, and a carboxyl- terminal transactivation domain. Here we show that each deletion mutant of Rta, including R1-119 (aa 1 to 119), R1-333, R1-441, R100-333, R100-605, R364-441, R401-441 and R401-605 alone cannot induce EBV lytic cycle when transfected into NA cells. However, R1-441, deleted 164 amino acids from the C terminus of Rta, is able to function as a dominant negative mutant, inhibiting the Rta-induced expression of Zta, EA-D, DNase, mDBP (major DNA binding protein), BHRF1, and BGLF4, and the transactivation ability of wild-type Rta on BGLF5, BRLF1, and BZLF1 promoter. By co-immunoprecipitation analysis and further deletion of Rta, we find that R1-441 can dimerize with wild-type Rta and inhibit Rta’s function. When the N-terminal 99 amino acid is deleted, the R100-441 cannot dimerize with wild-type Rta and cannot interfere with Rta’s function. Another C-terminal truncated mutant, R1-333, however, is also able to interact with wild-type Rta, but cannot interfere the transactivating ability of Rta.