Pendant la méiose, la division cellulaire qui forme les cellules haploïdes, les chromosomes homologues hérités de chacun des deux parents sont appariés et échangent des segments réciproques appelés crossing-overs (CO). Les CO ne sont pas distribués au hasard dans le génome et leur taux varie le long des chromosomes. Certains des mécanismes responsable ont été décrits chez les mammifères et la levure mais ne sont pas conservés chez les plantes. Les CO sont fortement inhibés dans l'hétérochromatine qui est riche en éléments répétés. Le degré élevé de méthylation d l'ADN qui caractérise les séquences répétées pourrait être un inhibiteur des CO. Cela a été clairement démontré chez le champignon Ascobolus immersus et des études récentes ont montré que la perte de méthylation modifiait la distribution des CO chez Arabidopsis thaliana. Le but de ma thèse a été de décrire plus précisément le rôle de la méthylation de l'ADN dans le contrôle des CO en l'absence de polymorphisme de séquence qui affecte aussi la recombinaison.Pour cela, j'ai mesuré la recombinaison dans différentes plantes dans lesquelles la méthylation de l'ADN a été partiellement ou totalement enlevée grâce à la mutation du gène ddm1. Pour tester l'effet opposé d'un gain de méthylation, j'ai aussi essayé de cibler la methylation de l'ADN à un point chaud de recombinaison connu. Mes résultats montrent que la parte de la méthylation de l'ADN entraîne une augmentation globale de la recombinaison. Paradoxalement, l'heterochromatine qui est normalement très méthylée est moins affectée par la perte de méthylation que le reste du chromosome, probablement car la méthylation de l'ADN a des effets à distance. L'augmentation de CO est accentuée dans les générations successives du mutant ddm1. Cependant, l'effet le plus important est observé dans les hétérozygotes où la moitié du génome seulement est hypométhylée, ce qui suggère un rôle complexe de la méthylation. Finalement, j'ai pu montrer que le polymorphisme affecte la recombinaison surtout dans l'hétérochromatine mais pas dans le sens attendu puisque les plantes homozygotes recombinent moins que les plantes hétérozygotes. / During meiosis, the cellular division that gives rise to haploid cells, homologous chromosomes inherited from each parent are paired and are subjected to reciprocal exchanges of chromosome segments called crossing-overs (COs). COs are not randomly distributed in the genome. Some of the involved mechanisms have recently been described in mammals and yeast bu they are not conserved in plants. Repeat-rich heterochromatin is suppressed for COs. The high level of DNA methylation associated with repeats could be an inhibitor of COs. This was clearly demonstrated in the fungus Ascobolus immersus and recent studies have shown that the loss of DNA methylation also affects COs in Arabidopsis thaliana. The aim of my thesis was to describe more precisely the role of DNA methylation in the control of CO distribution in the absence of any DNA sequence polymorphism which are known to affect recombination. For this purpose, I measured recombination in different plants where DNA methylation has been partially or completely removed thanks to the mutation of the DDM1 gene. To test the opposed effect of a gain of DNA methylation,.I also tried to target DNA methylation at a known recombination hotspot. My results show that the loss of DNA methylation induces a global increase of recombination. Paradoxically, the normally highly methylated heterochromatin is less affected by this loss than the rest of the chromosome, probably because DNA methylation has distal effects. The increased recombination is exacerbated in successive generations of the hypomethylated ddm1 mutants. However, the strongest effect is seen in the heterozygotes where only half of the genome is hypomethylated, suggesting a complex role in the control of CO distribution. Finally, I show that DNA sequence polymorphism affects mainly recombination in the heterochromatin but not in the expected sense, since homozygous plants recombine less than heterozygous.

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<p>This paper contains a study where we apply cross media and storytelling into the design process of a practical commercial campaign. The purpose is to learn more and deeper by using cross media and the ideal of storytelling practical. We applied a qualitative method for research of the project to provide a high-quality empirical work. The result shows that by using well-structured story early in the design process you will easily succeed with your cross media design.</p>

According to Naudé and Krugell (2003a) South Africa's cities are too small, dispersed, and over concentrated. In South Africa, households in the country's urban areas have average incomes almost thrice as high as the households in rural areas. More than 70% of South Africa's GDP is produced in only 19 urban areas (Naudé and Krugell 2003b). In Naudé and Krugell (2003a) it is stated that the rank-size rule shows that South Africa's urban agglomerations are too small and the cities mainly offer urbanization economies rather than localization economies. The main focus of this study will be looking at the specialization and diversity of South African cities. The aim is to determine whether certain cities should specialise in certain sectors, which they are currently involved in or should they add to their city and become more diverse and specialize in other sectors in order to promote economic growth. Many believe that a city which is more diverse would grow faster than a city specialising in a certain and thus be more beneficial to the economy than a specialized city would. This paper would like to address this phenomenon with regard to South African cities / Thesis (M.Com. (Economics))--North-West University, Potchefstroom Campus, 2006.

According to Naudé and Krugell (2003a) South Africa's cities are too small, dispersed, and over concentrated. In South Africa, households in the country's urban areas have average incomes almost thrice as high as the households in rural areas. More than 70% of South Africa's GDP is produced in only 19 urban areas (Naudé and Krugell 2003b). In Naudé and Krugell (2003a) it is stated that the rank-size rule shows that South Africa's urban agglomerations are too small and the cities mainly offer urbanization economies rather than localization economies. The main focus of this study will be looking at the specialization and diversity of South African cities. The aim is to determine whether certain cities should specialise in certain sectors, which they are currently involved in or should they add to their city and become more diverse and specialize in other sectors in order to promote economic growth. Many believe that a city which is more diverse would grow faster than a city specialising in a certain and thus be more beneficial to the economy than a specialized city would. This paper would like to address this phenomenon with regard to South African cities / Thesis (M.Com. (Economics))--North-West University, Potchefstroom Campus, 2006.

Thesis (M.A.)--University of Missouri-Columbia, 2008. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 12, 2009) Includes bibliographical references.

En génomique comparative, on considère classiquement trois forces déterminant l'évolution des séquences : la mutation, la sélection et la dérive génétique. Récemment, lors de l'étude de l'origine évolutive des variations de la composition en base des génomes, un quatrième agent a été identifié : la conversion génique biaisée (BGC). Le BGC est intimement lié à la recombinaison méiotique et semble présent chez la plupart des eucaryotes. Ce phénomène introduit une surreprésentation de certains allèles dans les produits méiotiques aboutissant à une augmentation de la fréquence de ces variants dans la population. Ce processus est capable de mimer et d'interférer avec la sélection naturelle. Il est donc important de le caractériser afin de pouvoir le distinguer efficacement de la sélection dans l'étude de l'adaptation à l'échelle moléculaire. C'est ce que nous nous attachons à faire dans le cadre de ce travail. Pour cela nous utilisons deux espèces modèles. Premièrement la levure Saccharomyces cerevisiae pour laquelle une carte de recombinaison haute résolution permettant l'analyse du processus de conversion, est disponible. L'étude approfondie de cette carte nous a permis de lever le voile sur les mécanismes moléculaires qui sous-tendent le BGC. Deuxièmement, grâce à des découvertes récentes sur la détermination des patrons de recombinaison via la protéine PRDM9 chez les mammifères, nous avons quantifié la dynamique et l'intensité de ce processus dans l'histoire évolutive récente de l'homme. Ces résultats nous ont permis de confirmer la place du BGC comme quatrième force d'évolution moléculaire, mais aussi de discuter de l'origine évolutive de ce phénomène / Usually, three main forces are considered when studying sequences evolution in comparative genomics : mutation, selection and genetic drift. Recently, a fourth process has been identified during the study of base composition landscapes in genomes : biased gene conversion (BGC). This phenomenon introduces an overrepresentation of certain alleles in meiosis products (gametes or spores) leading to an increase of the frequency of those variants in the population. Thus, it is able to mimic and interfere with natural selection. Hence, it is important to describe this phenomenon in order to be able to trustfully distinguish BGC and selection in the study of adaptation at the molecular scale. So, the main goal of this work is to analyze the molecular origin, the intensity and the dynamics of BGC. To do so, we use two model species. First, we use the yeast Saccharomyces cerevisiae because, for this specie, a high-resolution recombination map is available which allows a fine study of the conversion process. Analyzing this map led us to shed the light on the molecular mechanisms of BGC. Secondly, recent discoveries on the role of the PRDM9 protein in the determination of recombination landscapes in mammals allowed us to quantify the dynamics and intensity of BGC in the recent human history. Thanks to those two studies, we first confirmed that BGC is the fourth force of molecular evolution and we also provided hypotheses about the evolutionary origin of this process

Iu, Yiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 163-173). / Abstracts in English and Chinese ; questionnaires also in Chinese. / Abstracts --- p.i / Acknowledgements --- p.iii / Table of Contents --- p.iv / Introduction --- p.1 / Chapter A. --- Objectives and Significance --- p.1 / Chapter B. --- Academic Issues and Literature Review --- p.4 / Chapter C. --- Theories and Methodologies --- p.18 / Chapter D. --- Structure of the Thesis --- p.20 / Chapter Part I: --- The Making of a Seiyu Culture in Japan / Chapter Chapter 1: --- What is Seiyu? --- p.24 / Chapter 1.1 --- Definition of Seiyu --- p.24 / Chapter 1.2 --- Scope of Works --- p.27 / Chapter 1.3 --- Training Institutions and Agencies --- p.32 / Chapter Chapter 2: --- The Historical Development of the Seiyu Profession in Japan --- p.38 / Chapter Part II: --- Cultural and Social Significance of Seiyu Culture / Chapter Chapter 3: --- Seiyu as Art and Industry --- p.56 / Chapter 3.1 --- Internal Factors --- p.58 / Chapter 3.2 --- External Factors --- p.64 / Chapter Chapter 4: --- Cultural and Social Impact of the Seiyu Culture --- p.78 / Chapter 4.1 --- Cultural Impact --- p.78 / Chapter 4.2 --- Social Impact --- p.92 / Chapter Part III: --- Comparative Study on Japanese Seiyu and Hong Kong Voice Artists / Chapter Chapter 5: --- The Popularization of the Japanese Seiyu and Local Voice Artists in Hong Kong --- p.101 / Chapter 5.1 --- Japanese Seiyu Steal the Limelight in Hong Kong --- p.102 / Chapter 5.2 --- Hong Kong Voice Artists Move out from the Backstage --- p.112 / Chapter 5.3 --- The Comparison of the Reception of Japanese Seiyu with That of Local Voice Artists in Hong Kong --- p.117 / Chapter Chapter 6: --- Comparison of the Dubbing Profession between Japan and Hong Kong --- p.123 / Chapter 6.1 --- Structural Differences in Dubbing Profession --- p.126 / Chapter 6.2 --- The Role of Voice Dubbing in Popular Culture --- p.135 / Concluding Analysis --- p.147 / References --- p.163 / Appendix --- p.174 / Chapter I) --- Questionnaire of Seiyu Culture in Hong Kong --- p.174 / Chapter II) --- Sample Interview Questions for Seiyu Fans --- p.177 / Chapter III) --- Sample Interview Questions for Voice Artists --- p.178

Very often we are likely to hear how important it is as adults to help small children and pupils out of bullying situations, both for the bullied one and the bully. What we often tend to forget is that bullying situations among adults are as common as the ones children put up with. The only difference is that the ones adults go through is a much more silent one, and the bullies often have a better strategy on how to beat down their victims slowly. Some of the cases also show that the bullying that is happening among adults is similar to the one between children. The risks in the bullying that occurs in the work environment are such as: bad self-esteem, doubting in their roles as professionals, anger, depression, anxiety and in some cases can be so dangerous that the suffered one eventually commits suicide. Therefore I chose to examine what kind of view the interviewed educators have towards: What the definition of bullying is? What kinds of factors are causing the bullying? What kind of action-plans are there to prevent this from happening? Needless to say, the topic becomes more interesting when the authorities at work don’t show interest in taking the problems seriously, which almost give the bullies the impression that it’s acceptable to do so. Unfortunately, the results showed that the employees eventually decided to quit their jobs, because of all the harassments that didn’t stop and for the help they didn’t get from their bosses and neither did they’ve had contact with the Work Environment Agency. It is also of importance to mention that all three of the interviewed people are educators themselves and worked in a preschool environment during the bullying periods. The study has been examined by their perspective on the subject.