Evolutionarily conserved Pumilio (Pum) RNA-binding proteins act as translational repressors during embryo development and cell fate specification. Previous work in the lab has shown that over-expression of Pum2 (Pum2-EML) supports maintenance and suppresses mutilineage differentiation of murine multipotent HSC/MPP-like cell line EML. The subsequent analysis of HSC markers and functional analysis has revealed that wt EML cells share the LKS CD34 positive phenotype, whereas the majority Pum2-EML cells are similar to LKS CD34 negative. The CD34 positive wt EML cells can be divided into CD34low, CD34med and CD34high subpopulations, whereas Pum2-EML CD34 positive cells correspond to CD34low subpopulation. Colony forming assays have revealed that the overall multilineage differentiation of wt EML and Pum2-EML cells strongly correlates with the CD34 expression levels. Multiple experiments have revealed that purified CD34 negative and CD34 positive wt EML cells can generate each other and among CD34 positive wt EML cells the CD34low cells have the highest capacity to give rise to CD34 negative EML cells. We have proposed a model in which CD34 negative EML cells are more primitive cells in an "inactive" (differentiation inhibited) state, that give rise to CD3low "active" (differentiation ready) EML cells. The CD34low EML cells can revert back to the CD34 negative state or give rise to CD34med/high cells that can readily differentiate into multiple lineages. Based on that model, the over-expression of Pum2 leads to increased maintenance of cells in inactive CD34 negative state, and blocks development of CD34 positive cells past the CD34low stage. Cumulatively, these results support the notions that Pum2 could be involved in maintaining the balance between inactive and active state of multipotent hematopoietic cells. The c-kit receptor plays a vital role in self-renewal and differentiation of hematopoietic stem cells (HSC) and multipotent progenitors (MPPs). We have discovered that besides c-kit, the murine multipotent HSC/MPP-like cell line EML expresses the transcript and protein for a truncated form of c-kit, called tr-kit. Notably, the tr-kit transcript and protein levels were down-regulated during cytokine induced differentiation of HSC/MPP-like cell line EML into myelo-erythroid lineages. RT-PCR results show tr-kit is transcribed solely in cell populations enriched for LTR-HSC, STR-HSC and MPPs. The observation that tr-kit is co-expressed with c-kit only in more primitive, HSC and MPP-enriched cell populations raises an exciting possibility that tr-kit functions either as a new component of SCF/c-kit pathway, or is involved in a novel signaling pathway, present exclusively in HSC and MPPs. These findings necessitate functional characterization of tr-kit, and analysis of its potential role in the self-renewal, proliferation and/or differentiation of HSC and multipotent progenitors.

The purpose of the study is to better understand the factors that affect melt-wear in the armature-to-rail contact interface of an electromagnetic launcher (EML). In order to investigate the factors, the study uses finite element analysis (FEA) to vary parameters of a lab-scale EML at the Georgia Institute of Technology. FEA is used due to the complex nature of the system, which includes the geometry and various engineering aspects that the EML incorporates. The study focuses on an uncoupled analysis of the structural, electromagnetic (EMAG), thermal, and modal aspects. The reason for the uncoupled analysis was because the system was complex and there were computational limits. Also, by uncoupling the analysis fields, the way the parameters affected melt-wear could be viewed separately. The study varied the geometry of the armature, the stiffness of the rail system (compliance layer), and the material of the armature. The structural analysis was for the initial contact of the rail to the armature and found the von Mises stresses, contact area, and contact pressure. The EMAG analysis found the Lorentz forces in the system based on a current curve used in the lab-scale EML. The thermal analysis consisted of friction heating and Joule heating. The modal analysis was for the unstressed and pre-stressed armature. Based on the study conducted, it was found that aluminum would provide the best speeds due to its lighter mass, but lacked in the thermal resistance area. Tungsten provided the better thermal resistance, but lacked in the potential speed due to its heavier mass.

Elections are one of the most fundamental activities of a democratic society. As is the case in any other aspect of life, developments in technology have resulted changes in the voting procedure from using the traditional paper-based voting to voting by use of electronic means, or e-voting. E-voting involves using different forms of electronic means like / voting machines, voting via the Internet, telephone, SMS and digital interactive television. This thesis concerns voting by telephone, or televoting, it starts by giving a brief overview and evaluation of various models and technologies that are implemented within such systems. The aspects of televoting that have been investigated are technologies that provide a voice interface to the voter and conduct the voting process, namely the Election Markup Language (EML), Automated Speech Recognition (ASR) and Text-to-Speech (TTS).

Elections are one of the most fundamental activities of a democratic society. As is the case in any other aspect of life, developments in technology have resulted changes in the voting procedure from using the traditional paper-based voting to voting by use of electronic means, or e-voting. E-voting involves using different forms of electronic means like / voting machines, voting via the Internet, telephone, SMS and digital interactive television. This thesis concerns voting by telephone, or televoting, it starts by giving a brief overview and evaluation of various models and technologies that are implemented within such systems. The aspects of televoting that have been investigated are technologies that provide a voice interface to the voter and conduct the voting process, namely the Election Markup Language (EML), Automated Speech Recognition (ASR) and Text-to-Speech (TTS).

Magister Scientiae - MSc / Elections are one of the most fundamental activities of a democratic society. As is the case in any other aspect of life, developments in technology have resulted changes in the voting procedure from using the traditional paper-based voting to voting by use of electronic means, or e-voting. E-voting involves using different forms of electronic means like; voting machines, voting via the Internet, telephone, SMS and digital interactive television. This thesis concerns voting by telephone, or televoting, it starts by giving a brief overview and evaluation of various models and technologies that are implemented within such systems. The aspects of televoting that have been investigated are technologies that provide a voice interface to the voter and conduct the voting process, namely the Election Markup Language (EML), Automated Speech Recognition (ASR) and Text-to-Speech (TTS). / South Africa

Cette étude se situe au niveau de la couche physique d'un système de transmission optique terrestre de type réseau métropolitain. Il s'agit d'y intégrer un composant, le laser modulateur intégrés (Electroabsorption Modulated Laser ou EML) du III-V Lab Alcatel-Thales, un laboratoire industriel de composants optoélectroniques. Et ceci pour en diminuer la complexité par pré-distorsion apportée par la modulation du laser. Les distances de transmission étant limités par des phénomènes physiques intrinsèques aux fibres optiques, le but est de développer un schéma de fonctionnement des EML pouvant dépasser les limites fixées par la dispersion chromatique des fibres et ses effets non-linéaires, principe qui a été démontré avec un laser et un modulateur discret mais jamais avec un composant intégré. La technique est basée sur une pré-compensation de la dispersion chromatique en appliquant une modulation sur le laser de l'EML qui génère la porteuse optique préchirpée qui est ensuite modulée par le modulateur à électro-absorption, raison du nom donné à l'EML : Dual Electroabsorption Modulated Laser ou D-EML. C'est l'axe majeur de recherche car il met en évidence le principe de la compensation de dispersion permettant d'incrémenter les distances de transmission de 80 km à 160 km pour la première fois avec un composant monolithique. Une application Radio-sur-Fibre pour les réseaux d'accès a été explorée, elle est basée sur une modulation duale analogique, permettant l'extinction d'une raie de modulation optique générant ainsi un signal à bande latérale unique Single Side Band. Ce format permet de transporter des signaux I-Q très haut-débit sur des distances de plus de 100 km.

Ce travail présente deux approches pour la modélisation des structures de grains et de la ségrégation chimique associée à l'état de fonderie après solidification. La première approche est de développer un modèle basé sur une description semi-analytique des couches de diffusion chimique dans la phase solide et à l'extérieur des enveloppes des grains. L'originalité de ce modèle réside dans la prise en compte de la surfusion de germination des structures dendritique et eutectique. Nous avons appliqué le modèle développé aux gouttes solidifiées par lévitation électromagnétique (EML) et dont la germination de la structure primaire s'est produite spontanément. La technique EML est utilisée comme modèle expérimental pour produire des échantillons sphériques d'alliage aluminium–cuivre (Al-Cu) a différentes compositions nominales de cuivre. Pour chaque échantillon, nous avons étudié le cas d'une germination spontanée et le cas d'une germination déclenchée. Plusieurs degrés de surfusion ont été mesurés avant la germination des structures dendritique et eutectique. Des investigations expérimentales ont été menées pour caractériser une section centrale de chaque échantillon. Un microscope électronique à balayage (MEB), équipé d'un capteur rayon X, a été utilise pour l'analyse dispersive en énergie. Un ensemble complet de données a été généré pour chaque échantillon a travers des cartes de distribution du cuivre, de la structure eutectique et de l'espacement interdendritique secondaire. Le modèle permet une prédiction quantitative de la fraction de structure eutectique en accord avec les mesures effectuées et cela grâce à la prise en compte de la surfusion de germination eutectique. L'accord avec les mesures expérimentales est dû à la prise en compte de l'effet de la surfusion et de la recalescence eutectique. Dans la seconde approche, un modèle numérique 2D couplant Automate Cellulaire (CA) – Eléments Finis (FE) est développé pour la prédiction de la variation de la température et des cartes de ségrégation mesurées pour les échantillons Al-Cu. Un modèle de micro-ségrégation a été intégré dans chaque cellule de l'automate. Ce modèle permet de prendre en compte la surfusion de la germination de la phase primaire ainsi que la diffusion du soluté dans la phase solide. Les longueurs caractéristiques de diffusion ont été exprimé en fonction des espacements interdendritiques primaires et secondaires. Les équations de conservation d'énergie, de masse et de quantité de mouvement sont résolues par la méthode des éléments finis. Un nouveau schéma de couplage entre l'automate cellulaire et les éléments finis a été développé pour permettre l'adaptation du maillage. Un estimateur d'erreur géométrique a été intégré pour le contrôle de la taille et l'orientation des mailles afin d'optimiser la résolution par la méthode des éléments finis. L'application du modèle 2D CAFE a permis une compréhension avancée des résultats expérimentaux. Ce modèle a aussi été appliqué à la solidification d'une cavité rectangulaire d'un alliage étain-plomb. Les capacités du modèle pour l étude des transferts d'énergie et de masse aux échelles micro et macro ont été mise en évidence par le bon accord entre ces perditions et les mesures expérimentales (des cartes de température, de la macro–ségrégation et des structures de grains).

The Health Sector at the state of Kuwait is facing many challenges. One of which is public expectations in health are high, and thus, the Ministry of Health (MOH) in Kuwait has amplified the health expenditure by 86% since 2007. And since the medicine budget represents half of the total MOH budget, it is proposed that the development in health policy might be a suitable tool to control the inflation within the health budget. This thesis examines the opportunities and challenges of introducing an EML in Kuwait and the factors influencing its effectiveness. A mixed-methodology approach has been used to enhance and validate the data, in the form of interviews, comparative studies and questionnaires. One major limitation to the research was the lack of previous data relating to this work, and the information should be gathered in person in the form of hard copies, and later, the data was analysed using qualitative and quantitative approaches. It has been attained that, the EML might be a valuable tool if adopted and implemented appropriately, EML adjustment to country health situation is crucial for successful utilisation and fulfilling the concept objectives. Standard Treatment Guidelines are fundamental part of EM selection process, in Kuwait there were lack in the uniformity of the local STG, but fortunately, there is an eagerness to innovate, and the medicine situation might benefit from a type of organisation, overall, if the EML implemented efficiently in Kuwait, it might help in improving the general health and control the inflation in MOH budget.

The Health Sector at the state of Kuwait is facing many challenges. One of which is public expectations in health are high, and thus, the Ministry of Health (MOH) in Kuwait has amplified the health expenditure by 86% since 2007. And since the medicine budget represents half of the total MOH budget, it is proposed that the development in health policy might be a suitable tool to control the inflation within the health budget. This thesis examines the opportunities and challenges of introducing an EML in Kuwait and the factors influencing its effectiveness. A mixed-methodology approach has been used to enhance and validate the data, in the form of interviews, comparative studies and questionnaires. One major limitation to the research was the lack of previous data relating to this work, and the information should be gathered in person in the form of hard copies, and later, the data was analysed using qualitative and quantitative approaches. It has been attained that, the EML might be a valuable tool if adopted and implemented appropriately, EML adjustment to country health situation is crucial for successful utilisation and fulfilling the concept objectives. Standard Treatment Guidelines are fundamental part of EM selection process, in Kuwait there were lack in the uniformity of the local STG, but fortunately, there is an eagerness to innovate, and the medicine situation might benefit from a type of organisation, overall, if the EML implemented efficiently in Kuwait, it might help in improving the general health and control the inflation in MOH budget.

Light has a wide and profound non-visual impact on the human body. It is related to the suppression or synthesis of a hormone called melatonin which regulates the human circadian clock. In Nordic countries like Sweden, lack of natural light in winter may lead to negative health effects such as circadian disorders or depression. At the same time, the underground metro system in Stockholm carries more than one million passengers on a weekday. The lighting in the train carriage may have distinct circadian effects on the passengers. The paper takes the metro system in Stockholm as an example, calculates the non-visual effects of the artificial lighting in the train according to Equivalent Melanopic Lux (EML), Circadian Stimulus (CS) and Melanopic Equivalent Daylight Illuminance (M-EDI) Models, compares with current guidance and suggestions, considers the daylighting conditions of Stockholm, and proposes a new design solution with adjustable LEDs to achieve a better healthful circadian lighting result.