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Right Ventricle Curvature Maybe a Predictor for Pulmonary Valve Replacement Surgery Outcome: A Multi-Patient StudyZuo, Heng 27 August 2014 (has links)
"Patients with repaired tetralogy of Fallot (TOF) account for the majority of cases with late onset right ventricle (RV) failure. The current surgical approach, which includes pulmonary valve replacement/insertion (PVR), has yielded mixed results in terms of RV functional recovery. Therefore, it is of great interest for clinicians to identify parameters, which may be used to predict post-PVR outcome. Pre- and post-PVR cardiac magnetic resonance (CMR) data were obtained from 60 repaired TOF patients with consent obtained for analysis. RV ejection fraction (RVEF) change (post-PVR RVEF minus pre-PVR RVEF) was used to measure post-PVR improvement. The patients were divided into Group 1(optimal outcome) and Group 2 (poor outcome) for comparison. RV wall thickness (WT) and curvature were obtained from CMR data for statistical analysis. Using mean quarter values (one CMR slice = 4 quarters), statistically significant differences in circumferential curvature (C-curvature) and longitudinal curvature (L-curvature) at end-diastole (maximum RV volume) and WT and C-curvature at end-systole (minimum RV volume) between Group 1 and Group 2 were found. Correlations between average WT at systole and between L-curvature at diastole and the change of RVEF were statistically significant. Specifically, the correlation coefficient between average WT at systole and change of RVEF was – 0.2715, (p = 0.036) and between L-curvature at diastole and change of RVEF 0.3297 (p = 0.01). This initial study suggests that the RV longitudinal curvature and wall thickness may be used as a marker/predictor for PVR surgical outcome. "
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Proliferative vitreoretinopathy : a study of biological and clinical risk factors and new pharmacological therapiesKon, Chee Hing January 1997 (has links)
No description available.
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Range size heritability patterns in Carnivora arise from the interplay between evolutionary and geographic constraintsMACHÁČ, Antonín January 2011 (has links)
The thesis explores how the range sizes of carnivorans are shaped by geographic and evolutionary constraints. Employing modern spatial analyses and phylogenetic comparative methods, we illustrate that phylogenetically conserved climate tolerances delimit species? geographic constraints, which in turn shape the species? range size. Range size heritability patterns emerge as a consequence of this interplay between geographic and evolutionary constraints.
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The Drosophila Pvr Pathway Regulates Innate Immunity and Intestinal HomeostasisBond, David JE Unknown Date
No description available.
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Regulation of hematopoiesis in the freshwater crayfish, Pacifastacus leniusculus : role of transglutaminaseJunkunlo, Kingkamon January 2017 (has links)
The freshwater crayfish, Pacifastacus leniusculus, has been used as a model for studying hematopoiesis or blood cell production or hematopoiesis and immunity. The work of this thesis aims to investigate the impact of factors such as ROS signaling, Ast1, and the PVF/PVR signaling pathway in controlling stem cell behavior during hematopoiesis and specifically the role of the crosslinking enzyme transglutaminase (TGase) in regulation of hematopoiesis. The role of ROS in crayfish hematopoiesis was characterized by using the antioxidant named NAC to inhibit ROS production. Low ROS level resulted in a prolonged decrease in hemocyte numbers and a combined injection of LPS and NAC caused a slower rate of new hemocyte production. A low ROS level in cell cultures supplemented with crude Ast1 was found to inhibit cell spreading and a high extracellular TGase activity was detected on the surfaces of APC and HPT cells. We suggest that ROS serves as a prime signal to control proliferation and differentiation of progenitor cells by affecting extracellular TGase activity. We reported an inhibitory effect of Ast1 on TGase enzyme activity and on its crosslinking activity and consequently Ast1 affects the clot formation and thus coagulation by inhibiting the crosslinking activity of the TGase enzyme. Secretion of the clot protein (CP) and the production of CP filament network between spreading cells were observed in HPT cell cultures in vitro. In the presence of CP together with Ast1 in 3D-collagen-I cultures, HPT cells were found to be more elongated and they formed chains of cells throughout the surrounding matrix. In the HPT tissue, CP was located around the HPT cells or around the lobules of HPT, and thus, CP was demonstrated to be a part of ECM and to possibly function together with collagen in generating a suitable environment for HPT progenitor cells. The inhibition of PVF/PVR downstream signaling pathway by Sunitinib malate resulted in a dramatic change of cell morphology and induction of an increase cell surface area during cell culture. The addition of crude Ast1 into the cell cultures in vitro enhanced this effect. Consequently, cell migration was stimulated and a high extracellular TGase activity on HPT cell surface was found after this inhibition. In conclusion, the work in this thesis provides new insight in understanding the role of the extracellular matrix (ECM) and extracellular TGase activity in controlling stem cell activity.
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Etude des pluies intenses dans la region Cévennes-Vivarais à l'aide du radar volumique. Regionalisation des traitements radar et analyse granulométrique des pluies au sol.Chapon, Benoit 14 December 2006 (has links) (PDF)
La mesure quantitative de la pluie à l'aide du radar météorologique est soumise à la représentation de la distribution granulomètrique des gouttes d'eau à l'intérieur du système précipitant. Or actuellement une hypothèse forte est faite par les systèmes opérationels telle que la granulomètrie est invariante spatio-temporellement et donc caractérisée par un profil vertical de réflectivité et une relation de passage entre réflectivité et intensité de pluie uniques.<br /><br />Dans un premier temps nous avons élaboré un protocole de séparation des types de pluie à l'aide de la mesure du radar volumétrique de Bollène en nous basant sur les travaux antérieurs de Steiner et al.,1995 et Sanchez-Diezma et al. 2000. Ainsi nous avons régionalisé, sur les images radar de chaque pas de temps, deux classes de types de pluie: convectif stratiforme à bande brillante. A partir de cette séparation une application de correction de PVR propre à chaque région à été mise en place ainsi qu'un traitement réflectivité/pluie propre à chaque type de pluie. <br /> <br />Dans un deuxième temps une expérimentation granulomètrique des pluies cévenoles à été développé sur le site d'Alès durant l'automne 2004. Les mesures issues de cette étude ont permis de tester l'optimabilité de plusieurs méthodes de calculs de relations Z-R et également de proposer une relation propre aux cellules convectives en faisant le lien avec les mesures du radar de Bollène.
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Design and implementation of recording functionality for an IP-based set-top box / Design och implementation av inspelningsfunktionalitet för en IP-baserad set-top-boxGusic, Aner January 2004 (has links)
<p>This theses covers the design and implementation of recording functionality for a set-top box in a home network. An initial investigation is done and possibilities for extending the system to support specific features are presented. </p><p>Digital TV is becoming more common each day, and soon it will be more widely used than todays analogue standard. At the same time the need for recording TV shows remains the same or is increasing, which is shown by the number of PVR solutions popping up on the market. </p><p>The goal of this thesis work was to investigate the possibilities for extending an existing set-top box to support common PVR features and, if possible, to implement a prototype. This was supposed to be done in a home network environment with the set-top box as the digital media center. </p><p>A satisfying solution, covering basic recording functionality is defined and implemented. The solution includes recording to a USB hard drive and to a PC on the local network. On top of this, a graphical user interface is built and some simple benchmarks show the performance of the set-top box with the new functionality.</p>
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Design and implementation of recording functionality for an IP-based set-top box / Design och implementation av inspelningsfunktionalitet för en IP-baserad set-top-boxGusic, Aner January 2004 (has links)
This theses covers the design and implementation of recording functionality for a set-top box in a home network. An initial investigation is done and possibilities for extending the system to support specific features are presented. Digital TV is becoming more common each day, and soon it will be more widely used than todays analogue standard. At the same time the need for recording TV shows remains the same or is increasing, which is shown by the number of PVR solutions popping up on the market. The goal of this thesis work was to investigate the possibilities for extending an existing set-top box to support common PVR features and, if possible, to implement a prototype. This was supposed to be done in a home network environment with the set-top box as the digital media center. A satisfying solution, covering basic recording functionality is defined and implemented. The solution includes recording to a USB hard drive and to a PC on the local network. On top of this, a graphical user interface is built and some simple benchmarks show the performance of the set-top box with the new functionality.
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The User Perspective on Recorder Functionality and Navigation Management : Result from a usability evaluation of a Personal Video RecorderClaesson, Teresia January 2011 (has links)
The purpose of this study is to evaluate and give suggestions for interaction improvements to a user interface in a Personal Video Recorder. The study will focus on user learnability, user satisfaction, usability problems from the user interaction with the product and to make a set of interaction improvements. The participants performed a set of predefined tasks involving the recorder functionality and channel lists. The study involved three trials with seven tasks in each trial. The study showed that the time difference for Learnability – Time-on-Task between all trials were statistical significant for the user interface. The study also revealed a set of usability problems that were classified into different severity ratings. The study also showed that the participants were partly satisfied with the user interface. / Uppsatsen är egentligen på 18hp, var tvungen att fylla i 16hp då rätt alternativ inte fanns att tillgå.
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A Usability Evaluation of a Personal Video Recorder : Navigation and channel list management from a user perspectiveTanja, Rastad January 2011 (has links)
This thesis aimed to evaluate the user interaction with a Personal Video Recorder software in development by Zenterio. The evaluation focus was on learnability, satisfaction, identification of usability issues and proposing redesign to solve them. A user test with eleven participants was carried out, measuring task success, completion time, lostness, post-task satisfaction and post-session satisfaction across three trials. The seven user tasks concerned mainly channel lists and recording functionality; the former is examined closer in this paper. The results showed that the channel lists were somewhat difficult to manage initially but fairly quickly learned. The satisfaction was lower in the beginning and high after three trials. The results across all tasks followed similar learnability patterns and the overall satisfaction with the interface interaction pointed at the need of improvements. Nine usability issues were discovered concerning channel lists and navigation; they were rated by severity and redesign proposals were given. The issue with the strongest impact on the success of the interaction was the difficulty to find out how to open the submenus.
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