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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Impact of IPO on professional soccer clubs / Impact de l’IPO sur les clubs de football professionnels

Alfify, Mohammed 29 November 2018 (has links)
Dans les années 1990 et 2000, de nombreux clubs de football professionnel (CFP) ont été inscrits sur les marchés boursiers. Le succès des IPO sur les marchés du football, en particulier dans le domaine des performances sportives et financières, est incertain. Ainsi, nombreux recherches académiques empiriques ont été préconisées pour examiner la performance financière des IPO dans ces clubs. De telles recherches ont révélé que la performance financière des clubs cotés a diminuée. La plupart de ces recherches indiquent qu'il existe une relation entre la performance sportive et la performance financière dans ces clubs. Cependant, les chercheurs n'ont pas déterminé les facteurs de ce phénomène. Pour combler cette lacune dans la littérature antérieure, la thèse vise à identifier les facteurs déterminants de la performance sportive et financière listés dans CFP et à les comparer avec les déterminants des performances sportives et financières des CFP au Moyen-Orient.Cette thèse fournit d'autres preuves empiriques sur la relation entre la performance sportive et la performance financière dans les CFP listés. Le plus important est que les résultats de la thèse fournissent un nombre de facteurs déterminants qui affectent la performance sportive et financière dans les CFP. Parmi les résultats intéressants, on peut citer l’existence de facteurs similaires et différents entre les clubs de football européens et les clubs de football du Moyen-Orient. Cela semble être confirmé par le fait que le marché et les tournois et les règlements sont différents. De plus, l’impact des spectateurs est un résultat intéressant, dans lequel leur effet sur la performance financière est indirect, alors qu’il est direct sur la performance sportive. Cependant, la juste valeur du club est incertaine en raison du manque de divulgation et de détail des informations comptables. Nous suggérons donc d'améliorer la gouvernance d'entreprise pour améliorer la transparence et la responsabilité. De plus, la thèse suggère que la perspective de la gestion stratégique est un facteur important pour traiter la performance financière non durable des CFP, en particulier à long terme afin de mesurer la juste valeur du club. Cela a conduit à gagner en pertinence compte tenu de l’importance de la gestion stratégique dans les futures recherches universitaires. Ainsi, nous pouvons poser la question suivante: dans quelle mesure l’introduction en bourse est-elle durable dans les clubs de football professionnels? / In 1990s and 2000s many professional soccer (PSCs) clubs have been listed IPO in stock markets. The success of IPO in soccer markets, especially in the field of sports and financial performance is uncertain. Thus, number of empirical academic researches have been advocated to examine financial performance of IPO in these clubs. Such researches found financial performance of listed clubs is declined. Most of those researches indicate there is relationship between sports performance and financial performance in those listed clubs. However, researchers have not determine the factors of this phenomenon. To bridge this gap in the past literature, thesis aims to identify the determining factors of sports and financial performance in listed PSCs and to compare them with determinants of sports and financial performance of PSCs in Middle East.This thesis provides further empirical evidence on the relationship between sports and financial performance in listed PSCs. More importantly, results of thesis provide number of determining factors that affect sports and financial performance in PSCs. An interesting results, there are some similar and dissimilar factors between European soccer clubs and Middle east soccer clubs. This seemed to be confirmed by the fact that market and tournament and regulations are different. Furthermore, impact of spectators is interesting result, in which their effect on financial performance is indirect, while direct on sports performance. Yet, fair value of club is uncertain because lack of disclosure and detail accounting information. Thus, we suggest improving corporate governance to enhance transparency and accountability. Moreover, thesis suggest that strategic management perspective is important factor to treat unsustainable financial performance of PSCs, especially in long term in order to measure fair value of club. This lead to gain more relevance considering the importance of strategic management in future academic researches. Thus, we can raise the following question is to which extent IPO is sustainable in professional soccer clubs?
2

Approche systématique basée sur fUML pour formaliser la sémantique d’exécution des profils UML / A Systematic Approach based on fUML to Formalize UML Profiles Execution Semantics

Tatibouët, Jérémie 16 October 2014 (has links)
Les profils permettent de customiser UML pour un domaine particulier. Cette customisation se fait par l’ajout de concepts (stéréotypes) relatifs au domaine, l’ajout de contraintes sur ces concepts ainsi que la résolution de points de variation sémantiques. Il existe un processus établit et documenté dans l’état de l’art permettant de construire la syntaxe de ces langages basés sur UML. En revanche, ce processus ne couvre pas l’aspect formalisation de la sémantique et les propositions issues de l’état de l’art ne présentent pas d’approches systématiques pour traiter ce problème.La formalisation de la sémantique est un point essentiel de la construction d’un langage car elle permet de donner le sens des constructions syntaxiques. Pour être efficace, la formalisation de la sémantique d’un langage doit être menée conjointement à une action de normalisation. L’intérêt d’avoir une sémantique formelle et standard pour un langage est qu’elle permet aux modèles définis dans ce langage d’être exploités (analyse, exécution, simulation, etc.) de manière équivalente entre les outils. Cette équivalence permet aux utilisateurs d’observer des interprétations identiques d’un même modèle entre différents outils et donc d’avoir une compréhension commune du modèle et de la sémantique associée. Dans le contexte des profils, les actions de normalisations menées par l’OMG se concentrent exclusivement sur la syntaxe et la formalisation de la sémantique est négligée. Nous proposons de répondre à ce problème en nous appuyant sur les spécifications fUML et PSCS qui définissent une sémantique normative pour un sous-ensemble d’UML.Dans un premier temps, nous définissons deux méthodologies alternatives s’appuyant sur ces standards permettant de formaliser la sémantique d’exécution d’un profil UML. Dans la première méthodologie la sémantique d’exécution d’un profil est formalisée au niveau du modèle de domaine. La forme exécutable d’un modèle applicatif profilé est obtenue par transformation de modèle. Dans la seconde méthodologie, la sémantique est définie directement pour le profil. Le modèle qui la formalise est une extension du modèle sémantique de fUML/PSCS formalisée avec fUML. Les modèles sémantiques obtenus sont conformes à fUML ce qui les rend par construction exécutables et directement exploitables dans n’importe quel outil implantant les normes UML et fUML. Dans un deuxième temps, nous comparons nos approches sur la base de trois critères : l’effort de modélisation requis pour produire le modèle sémantique, la préservation de la sémantique de base d’UML définie par fUML/PSCS et la possibilité d’identifier rapidement les relations entre les stéréotypes et leurs sémantiques. Cette comparaison, nous permet de montrer la capacité de notre seconde méthodologie à prendre en compte des extensions clefs de la sémantique de base d’UML dans le contexte des profils. Ces éléments clefs sont : la délégation du contrôle, l’instanciation et les communications. L’ensemble de nos contributions ont été outillées dans le contexte de l’outil d’exécution de modèles MOKA qui est intégré au modeleur UML/SysML Papyrus. / UML profiles enable the UML to be tailored to a particular domain. To do so, a profile adds domain specific concepts (i.e., stereotypes) and constraints to UML and disambiguates specific semantic variation points. The design process for abstract syntax of profiles is well documented in the literature. However, specification of the semantics is neglected. According to our researches, there are no proposals in the state-of-the-art that define a systematic approach to solve this problem.Semantic formalization is a key point of language design. It enables to formally define the meaning of syntactic elements. In order to be efficient, the formalization activity must be realized in parallel with a standardization activity. The interest to have a language with a formal standardized semantic is to enable models defined using this latter to be interpreted (analysis, execution, simulation) in equivalent way between tools implementing the semantics. This equivalence enables users to observe similar interpretations of the same model between different tools and therefore to have a shared understanding of this model and the associated semantic.In the context of UML profiles, normalization activities leaded by the OMG are focused on the syntax. The semantic formalization aspect is neglected. We propose to address this problem by relying on fUML and PSCS OMG (Object Management Group) specifications. These standards formalize execution semantics for a subset of UML (classes, composite structures, and activities).Firstly, we define two methodologies relying on these standards to formalize execution semantics of UML profiles execution semantics. The first methodology defines the execution semantics for the domain model underlying the profile. The executable form of an applicative model defined using the profile is obtained by model transformation. In the second methodology, semantics are defined directly for the profile by extending the semantic model of fUML/PSCS using fUML. By being conform to fUML, the semantic model is by construction executable and can be directly used in any tools implementing the UML and fUML standards.Secondly, we compare our approaches against the following criteria: the modelling effort required to build the semantic model, the capability of the methodology to preserve the UML semantics (i.e., the one defined by fUML/PSCS) and the capability to identify clearly the relationships between the stereotypes and their semantics. This comparison enables us to demonstrate the capacity of the second methodology to define key extensions of the UML semantics in the context of a profile. These latter are: the control delegation, the instantiation, and the communications. The contributions have been implemented in our model execution framework Moka which is integrated in the open-source UML/SysML modeling tool Papyrus.
3

Effects of IFRS adoption on the financial statements of Nigerian listed entities : the case of oil and gas companies

Bala, Masud January 2015 (has links)
On 28 July 2010, the Nigerian Federal Executive Council approved January 1, 2012 as the effective date for the convergence of Nigerian Statement of Accounting Standards (SAS) or Nigerian GAAP (NG-GAAP) with International Financial Reporting Standards (IFRS). By this pronouncement, all publicly listed companies and significant public interest entities in Nigeria were statutorily required to issue IFRS based financial statements for the year ended December, 2012. This study investigates the impact of the adoption of IFRS on the financial statements of Nigerian listed Oil and Gas entities using six years of data which covers three years before and three years after IFRS adoption in Nigeria and other African countries. First, the study evaluates the impact of IFRS adoption on the Exploration and Evaluation (E&E) expenditures of listed Oil and Gas companies. Second, it examines the impact of IFRS adoption on the provision for decommissioning of Oil and Gas installations and environmental rehabilitation expenditures. Third, the study analyses the impact of the adoption of IFRS on the average daily Crude Oil production cost per Barrel. Fourth, it examines the extent to which the adoption and implementation of IFRS affects the Key Performance Indicators (KPIs) of listed Oil and Gas companies. The study further explores the impact of IFRS adoption on the contractual relationships between Nigerian Government and Oil and Gas companies in terms of Joint Ventures (JVs) and Production Sharing Contracts (PSCs) as it relates to taxes, royalties, bonuses and Profit Oil Split. A Paired Samples t-test, Wilcoxon Signed Rank test and Gray’s (Gray, 1980) Index of Conservatism analyses were conducted simultaneously where the accounting numbers, financial ratios and industry specific performance measures of GAAP and IFRS were computed and analysed and the significance of the differences of the mean, median and Conservatism Index values were compared before and after IFRS adoption. Questionnaires were then administered to the key stakeholders in the adoption and implementation of IFRS and the responses collated and analysed. The results of the analyses reveal that most of the accounting numbers, financial ratios and industry specific performance measures examined changed significantly as a result of the transition from GAAP to IFRS. The E&E expenditures and the mean cost of Crude Oil production per barrel of Oil and Gas companies increased significantly. The GAAP values of inventories, GPM, ROA, Equity and TA were also significantly different from the IFRS values. However, the differences in the provision for decommissioning expenditures were not statistically significant. Gray’s (Gray, 1980) Conservatism Index shows that Oil and Gas companies were more conservative under GAAP when compared to the IFRS regime. The Questionnaire analyses reveal that IFRS based financial statements are of higher quality, easier to prepare and present to management and easier to compare among competitors across the Oil and Gas sector but slightly more difficult to audit compared to GAAP based financial statements. To my knowledge, this is the first empirical research to investigate the impact of IFRS adoption on the financial statements of listed Oil and Gas companies. The study will therefore make an enormous contribution to academic literature and body of knowledge and void the existing knowledge gap regarding the impact and implications of IFRS adoption on the financial statements of Oil and Gas companies.
4

Insights into Differentiation of Mouse Pluripotent Stem Cells to Neural Lineage

Verma, Isha January 2016 (has links) (PDF)
Pluripotent stem cells (PSCs: ESCs and iPSCs) provide an excellent model system for studying neural development and function. These cells also serve as a reliable source of cell replacement for the treatment of various neurodegenerative diseases and disorders. In view of these applications of PSCs, multiple protocols have been developed to direct their differentiation into neural lineage. However, many of these protocols are limiting in terms of (a) low efficiency of generation of neural cells after long-term culture, (b) requirement of exogenous factors to induce and enhance neural differentiation and (c) supplementation of PSC culture medium with serum. Therefore, in the present study, attempts were made to achieve enhanced efficiency of neural differentiation of PSCs in the absence of exogenous molecules by employing a defined culture medium containing knockout serum replacement (KSR). KSR-based culture system was tested with our in-house-derived EGFP-transgenic ‘GS-2’ ES-cell and ‘N9’ iPS-cell lines and the wild-type ‘D3’ ES-cell line. In KSR medium, PSC-derived EBs predominantly generated neural cells from their post-attachment outgrowths and the complexity of neural networks increased as the culture progressed. Molecular phenotyping of PSC-derived neural cells was performed based on the expression of neural markers both at the mRNA and protein levels. qPCR analysis revealed the expression of markers corresponding to multiple neural cell types, including glutamatergic, GABAergic, cholinergic, serotonergic and dopaminergic neurons, astrocytes and oligodendrocytes, at various time points during the culture. RNA expression studies were confirmed via immunocytochemical analysis of the expression of neural markers. On day 15 of culture, FACS quantitation revealed the efficient generation of NES+ neural progenitors (~16-18%), MAP2+ mature neurons (~12-26%) and GFAP+ astrocytes (~30-63%) from the three PSC lines. Functional assessment of the generated neurons was performed by electrophysiological analysis of passive (RMP) and active (threshold, amplitude, FWHM and outward and inward currents) membrane properties. In order to investigate the role of default pathway in neural differentiation of PSCs in KSR medium, various strategies were employed. GS-2 ES-cells were cultured in the presence of different serum-free supplements; predominant differentiation into neural lineage was achieved in the B27-supplemented medium. The supplementation of KSR medium with BMP4 failed to show any effect of neural differentiation of GS-2 ES-cells. Also, EBs were switched between KSR- and FBS-supplemented culture conditions on day 2 or day 5 of culture. These experiments indicated that KSR medium promoted the generation of neural cell fates at the expense of differentiation to non-neural lineages. Interestingly, differentiation of P19 EC-cells in KSR medium also resulted in the predominant neural differentiation. These experiments collectively suggested the importance of default pathway in neural differentiation of PSCs in KSR medium. Additionally, efforts were made to enrich PSC-derived neural cells and also to enhance the efficiency of neural differentiation of PSCs. The removal of central EB-core from its peripheral neural outgrowth via scooping resulted in the enrichment of neural cells by ~1.3-2.1 folds. Significant increases were observed in the percentages of GS-2 ES-cell-derived MAP2+ mature neurons and GFAP+ astrocytes. Also, FGF2 supplementation of KSR medium was tested as a strategy to achieve enhanced efficiency of neural differentiation. Preliminary studies suggested an increase in the percentage of NES+ neural progenitors in the presence of FGF2. Taken together, KSR-based culture system offers a simple, defined and efficient method to achieve neural differentiation of PSCs in short time duration in the absence of exogenous factors. KSR-based culture system can be employed to generate specific neural cell types, study molecular regulation of neural differentiation and in disease modeling. Also, it can be used to develop a platform for high-throughput screening of potential neurogenic molecules and for dissecting their mechanisms of action.
5

Application of Nanostructured Materials and Multi-junction Structure in Polymer Solar Cells

Gao, Yangqin 09 December 2015 (has links)
With power conversion efficiency surpassing the 10% milestone for commercialization, photovoltaic technology based on solution-processable polymer solar cells (PSCs) provides a promising route towards a cost-efficient strategy to address the ever-increasing worldwide energy demands. However, to make PSCs successful, challenges such as insufficient light absorption, high maintenance costs, and relatively high production costs must be addressed. As solutions to some of these problems, the unique properties of nanostructured materials and complimentary light absorption in multi-junction device structure could prove to be highly beneficial. As a starting point, integrating nanostructure-based transparent self-cleaning surfaces in PSCs was investigated first. By controlling the length of the hydrothermally grown ZnO nanorods and covering their surface with a thin layer of chemical vapor-deposited SiO2, a highly transparent and UV-resistant superhydrophobic surface was constructed. Integrating the transparent superhydrophobic surface in a PSC shows minimal impact on the figure of merit of the PSC. To address the low mechanical durability of the transparent superhydrophobic surface based on SiO2-coated ZnO nanorods, a novel method inspired by the water condensation process was developed. This method involved directly growing hollow silica half-nanospheres on the substrate through the condensation of water in the presence of a silica precursor. Benefit from the decreased back scattering efficiency and increased light transport mean free path arise from the hollow nature, a transparent superhydrophobic surface was realized using submicrometer sized silica half-nanospheres. The decent mechanical property of silica and the “direct-grown” protocol are expected to impart improved mechanical durability to the transparent superhydrophobic surface. Regarding the application of multi-junction device structure in PSCs, homo multi-junction PSCs were constructed from an identical polymer absorber, in which the homo-tandem device showed an enhanced power conversion efficiency (PCE) (8.3% vs 7.7%) relative to the optimized single junction PSC. The high open voltage (>1.8 V) achieved in homo-tandem PSCs allowed for water splitting with an estimated solar-to-fuel conversion efficiency of 6%. Lastly, a hybrid tandem cell was also constructed using a polymer and a colloidal quantum dot subcell. Different hybrid tandem device architectures were proposed and show a promising PCE of 6.7%.
6

A Qualitative Method for Dynamic Transport Selection in Heterogeneous Wireless Environments

Duffin, Heidi R. 23 August 2004 (has links) (PDF)
Computing devices are commonly equipped with multiple transport technologies such as IrDA, Bluetooth and WiFi. Transport switching technologies, such as Quality of Transport (QoT), take advantage of this heterogeneity to keep network sessions active as users move in and out of range of various transports or as the networking environment changes. During an active session, the goal is to keep the device connected over the best transport currently available. To accomplish that, this thesis introduces a two-phase decision making protocol. In phase one, intra-device prioritization, users indicate the relative importance of criteria such as speed, power, service charge, or signal range through a comprehensive user interface. QoT-enabled devices process this information with the prioritized soft constraint satisfaction (PSCS) scoring function to ascertain the transport that best meets the user's needs. The second phase, inter-device negotiation, facilitates two QoT-enabled devices in agreeing to a unified selection of the best transport. This phase uses a modified version of the PSCS scoring function based on the preferences of both users. Additionally, devices may utilize multiple transports simultaneously to more accurately meet user demands. The PSCS scoring function considers pairs of transports and calculates the ratio that will yield the desired performance. Another set of functions, also presented in this thesis, is then used to accomplish the desired performance level despite the potential introduction of additional overhead.
7

Efficient, monolithic large area organohalide perovskite solar cells

Hambsch, Mike, Lin, Qianqian, Armin, Ardalan, Burn, Paul L., Meredith, Paul 19 December 2019 (has links)
Solar cells based on organohalide perovskites (PSCs) have made rapid progress in recent years and are a promising emerging technology. An important next evolutionary step for PSCs is their up-scaling to commercially relevant dimensions. The main challenges in scaling PSCs to be compatible with current c-Si cells are related to the limited conductivity of the transparent electrode, and the processing of a uniform and defect-free organohalide perovskite layer over large areas. In this work we present a generic and simple approach to realizing efficient solution-processed, monolithic solar cells based on methylammonium lead iodide (CH₃NH₃PbI₃). Our devices have an aperture area of 25 cm² without relying on an interconnected strip design, therefore reducing the complexity of the fabrication process and enhancing compatibility with the c-Si cell geometry. We utilize simple aluminum grid lines to increase the conductivity of the transparent electrode. These grid lines were exposed to an UV-ozone plasma to grow a thin aluminum oxide layer. This dramatically improves the wetting and film forming of the organohalide perovskite junction on top of the lines, reducing the probability of short circuits between the grid and the top electrode. The best devices employing these modified grids achieved power conversion efficiencies of up to 6.8%.
8

Insights Into Molecular Regulation Of Cardiomyocyte Differentiation Of Mouse Pluripotent Stem Cells

Abbey, Deepti 07 1900 (has links) (PDF)
Pluripotent stem cells (PSCs) are specialized cells, which have remarkable ability to maintain in an undifferentiated state and are capable of undergoing differentiation to three germ-layer lineage cell types, under differentiation-enabling conditions. PSCs include embryonic stem (ES)-cells, embryonal carcinoma (EC)-cells and embryonic germ (EG)-cells. ES-cells are derived from the inner cell mass (ICM) of day 3.5 blastocysts (mouse). On the other hand, EC- and EG-cells have different source of origin and exhibit some differences in terms of their differentiation abilities and culture requirements. These PSCs act as an ideal in-vitro model system to study early mammalian development and cell differentiation and, they could potentially be used for experimental cell-based therapy for a number of diseases. However, one of the problems encountered is the immune rejection of transplanted cells. For this, immune-matched induced pluripotent stem (iPS)-cells have been derived from somatic cells, by forced expression of a few stemness genes. Although, human PSCs lines are being experimented, their cell-therapeutic potential is still far from being thoroughly tested due to lack of our understanding regarding lineage-specific differentiation, homing and structural-functional integration of differentiated cell types in the host environment. To understand these mechanisms, it is desirable to have fluorescently-marked PSCs and their differentiated cell-types, which could facilitate experimental cell transplantation studies. In this regard, our laboratory has earlier generated enhanced green fluorescent protein (EGFP)-expressing FVB/N transgenic ‘green’ mouse: GU-3 line (Devgan et al., 2003). This transgenic mouse has been an excellent source of intrinsically green fluorescent cell types. Recently, we have derived a ‘GS-2’ ES-cell line from the GU-3 mouse line (Singh et al., 2012). Additionally, we envisaged the need for developing an iPS-cell line from the GU-3 mouse and then use them for studying cell differentiation. Thus, aims of the study described in the thesis are to: (1) develop an experimental system to derive EGFP-expressing fluorescently-marked iPS-cell line from a genetically non-permissive FVB/N mouse strain, characterize the established iPS-cell line and achieve differentiation of various cell types from EGFP-expressing iPS-cell line; (2) to study differentiation phenomenon, in particular to cardiac lineage, using select-cardiogenesis modulators and (3) to assess the gene-expression profiles and signaling system associated with cardiomyocyte differentiation of PSCs. This thesis is divided into four chapters with the 1st chapter being a review of literature followed by three data chapters. In the chapter I of the thesis, a comprehensive up-to¬date review of literature is provided pertaining to PSCs, their classification, derivation strategies especially for reprogramming of somatic cells for iPSC generation, their differentiation potential and characterization, particularly to cardiac lineage. Various molecular regulators involved in cardiac differentiation of PSCs with emphasis on epigenetic regulation involving DNA methylation and signaling pathways involved are described in detail. Subsequently, various approaches used for enhanced cardiac differentiation of PSCs and the therapeutic potential of PSC-derived differentiated cell types to treat disease(s) are discussed. Chapter-II describes the successful establishment of a permanent iPS-cell line (named ‘N9’ iPS-cell line) from the non-permissive FVB/N EGFP-transgenic GU-3 ‘green’ mouse. This chapter provides results pertaining to detailed derivation strategy and characterization of the ‘N9’ iPS-cell line which includes colony morphology, expansion (proliferation) efficiency, alkaline phosphatase staining, pluripotent markers’ expression analysis by qPCR and immunostaining approaches and karyotyping analysis. Further, in order to thoroughly assess the differentiation competence of the ‘N9’ iPS¬cell line, assessment of in-vitro and in-vivo differentiation potential of the ‘N9’ iPS-cell line by embryoid body (EB) formation and teratoma formation in nude mice and its detailed histological analysis showing three germ layer cell types and their derivatives were performed, followed by the generation of chimeric blastocysts by aggregation method. This established N9 iPS-cell line could potentially offer a suitable model system to study cardiac differentiation along with other established PSC lines such as the GS-2 and D3 ES-cell lines and the P19 EC-cell line. Following the establishment of the system to study cardiac differentiation of PSC lines, efforts were made to understand the biology of cardiac differentiation of PSCs (wild¬type and EGFP-transgenic PSC lines and P19 EC-cell line) using small molecules as modulators. Data pertaining to this is described in Chapter-III. The possible involvement of epigenetic regulation of cardiogenesis for example, DNA methylation changes in cardiogenesis-associated genes is studied using 5-aza cytidine as one of the chromatin modifiers. In order to understand the cardiac differentiation phenomenon, as a consequence of using 5-aza cytidine in cell culture, it was important to investigate its ability to induce/mediate cardiac differentiation. This involved an assessment by quantitating the cardiac beating phenotype and correlating this with enhanced cardiac-gene expression profiles. Further, DNA methylation regulation of cardiogenesis¬associated genes is described using various DNA methylation analysis techniques. Moreover, the possible involvement of other signaling members in mediating the cardiac differentiation is also studied using the P19 EC-cells. Results pertaining to the above findings are described in detail in the Chapter-III. Chapter-IV is focused on various efforts made towards investigating the ability of ascorbic acid to enhance cardiac differentiation of mouse ES-cells (GS-2 and D3 lines). Ascorbic acid has been implicated to be influencing cardiogenesis and it is reported to enhance differentiation of various cell types under certain culture conditions. Results pertaining to enhancement of cardiac differentiation of PSCs using ascorbic acid are presented in this chapter. This included assessment by quantitating cardiac beating phenotype and its correlation with enhanced cardiogenesis-associated gene expression profiles. Besides, estimation on the sorted cardiomyocyte population, derived from PSCs was also made using mature-cardiac marker. The possible underlying signaling mechanism involved was also studied in detail, using specific inhibitors for pERK (U0126), integrin signaling (pFAK; PP2) and collagen synthesis (DHP), in order to ascertain their involvement in ascorbic acid-mediated cardiac differentiation of mouse ES-cells. Subsequent to the three data chapters (II-IV), separate sections are provided for ‘Summary and Conclusion’ and for ‘Bibliography’, cited in the thesis. The overall scope of the study has been to understand the basic biology of cardiac differentiation from PSCs (EC-cells, iPS-cells and transgenic and wild-type ES-cells) and to assess, by using certain small molecules, whether PSCs could be coaxed to enhance the differentiation to a particular cell type (cardiac). The data contained in this thesis addresses the above theme.

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