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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.
501

Justiça restaurativa na escola: trabalhando as relações sociomorais

Baroni, Mariana Custódio de Souza [UNESP] 19 August 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-19Bitstream added on 2014-06-13T20:33:28Z : No. of bitstreams: 1 baroni_mcs_me_prud.pdf: 894215 bytes, checksum: 3b0ef84c3fec119e9f05ee8fbcf415ae (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho, intitulado “Justiça Restaurativa na Escola: trabalhando as relações sociomorais”, versa sobre a justiça restaurativa como uma proposta de resolução dos conflitos escolares. Relaciona os estilos de resolução de conflitos com os princípios de justiça restaurativa investigando como estes podem alicerçar a construção de ambientes sociomorais na escola de forma a possibilitarem a discussão e o fortalecimento de conceitos e valores morais que contribuam para a consolidação da cooperação entre alunos, para a construção da autonomia e para o combate à violência. Ele pertence à linha de pesquisa “Processos Formativos, Diferenças e Valores”, do Programa de Pós-Graduação em Educação da Faculdade de Ciências e Tecnologia, Universidade Estadual Paulista de Presidente Prudente e recebeu apoio financeiro da Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP. O interesse por esta pesquisa partiu da constatação do aumento desenfreado das situações de violência vivenciadas pela escola; surgiu da nossa preocupação com uma possível crise de valores morais que possa ter desencadeado a banalização da violência na escola. Levando isso em conta, estabelecemos como objetivo principal deste trabalho verificar se a justiça restaurativa pode se apresentar como um instrumento positivo à resolução de conflitos e combate à violência escolar. Para isso, estudamos, em Psicologia, a teoria de Piaget sobre o desenvolvimento moral da criança. Tomamos como referencial, no campo da Justiça Restaurativa, o projeto “Justiça e Educação em Heliópolis e Guarulhos: parceria para a cidadania” que inseriu, no segundo semestre de 2006, nas escolas da rede pública de São Paulo (Heliópolis e Guarulhos), espaços, denominados Círculos Restaurativos... / The present study, entitled “Restorative Justice at School: working socio-moral relationships”, is about restorative justice as an proposal of scholar conflicts resolution. It relates the different styles of conflicts resolution and the principles of restorative justice; at the same time, it investigates in what extend these can support the construction of socio-moral environments in school in order to allow discussion and provides the strengthening of concepts and moral values that contributes to consolidate cooperation among students, aiming autonomy and violence fighting. This study is part of the research line “Formative Process< Differences, Values”, of the Post Graduation Program in Education of Science and Technology College of Universidade Estadual Paulista from Presidente Prudente. It was funded by Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP. The interest in this subject originated because it was found that violence in school has increased a lot. Thus, we worry that a possible crisis of moral values has initiated violence trivialization in school. Considering this, the main objective of this research is to verify if restorative justice can be a positive instrument in order to conflicts resolution and violence fighting. To do so, we studied in Psychology, Piaget’s theory about children’s moral development. Our referential in Restorative... (Complete abstract click electronic access below)
502

Political ecology of water and territorialization of social struggle. Lomas de Zamora Water Forum’s experience / Ecología política del agua y territorialización de las luchas sociales. La experiencia del foro hídrico de Lomas de Zamora

Merlinsky, María Gabriela 25 September 2017 (has links)
En este artículo desarrollamos un análisis de las acciones colectivas por el acceso al agua y el saneamiento en la metrópolis de Buenos Aires. Nos interesa dar cuenta de la construcción social y política de la cuestión hídrica. Para ello, analizamos la emergencia de conflictos y reclamos por justicia ambiental, donde se elaboran nuevos conocimientos acerca del ciclo hidrosocial. La investigación se basó en un estudio de caso que analiza la experiencia del «Foro Hídrico de Lomas de Zamora», una organización que desarrolla acciones en la cuenca baja del Matanza-Riachuelo. El trabajo busca explicar la resonancia política de estas acciones en términos de la territorialización de los conflictos y la producción de conocimiento contraexperto. Nos proponemos mostrar la resonancia que tiene esta experiencia en la organización colectiva y en la construcción de nuevos lenguajes de derechos.s. / This article we develops an analysis of collective action for water access and sanitation in the Buenos Aires metropolis. It intends to give an account of the social and political construction of water issue. To this end, it analyzes the emergence of conflicts and claims for environmental justice that create new knowledge about the hydrosocial cycle. The research was based on a case study that examines the experience of the «Foro Hídrico de Lomas de Zamora» (Lomas de Zamora Water Forum), an organization developing actions in the lower basin of the Matanza-Riachuelo river. The results of the study show the political resonance of these actions in terms of the territorialization of conflicts and the production of counter-expertise knowledge. We aim to show the resonance that this experience has in collective organization and the construction of new languages of rights.
503

MediaÃÃo e Conflitos em Espiral: Encontros e Desencontros do Estado e dos Movimentos Sociais no Pontal do Paranapanema / Mediation And Conflicts In Spiral: Meetings And Misunderstandings Of State And Social Movements In Pontal Do Paranapanema

Tania Marcia Oliveira de Andrade 25 July 2006 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Este trabalho trata de conflitos coletivos rurais e de acordos construÃdos para sua pacificaÃÃo em um processo de mediaÃÃo estatal. Inicia pela histÃria de 150 anos de fraudes e grilagem no Pontal do Paranapanema, acompanhando a transformaÃÃo da luta de resistÃncia dos posseiros em grandes ocupaÃÃes de terra lideradas pelo Movimento Sem Terra (MST), num conflito coletivo de grandes proporÃÃes que ganhou as manchetes nacionais e internacionais em 1995. A partir daÃ, traÃa um perfil histÃrico dos principais atores sociais envolvidos â sem-terra, fazendeiros e Estado â e resgata as circunstÃncias que culminaram na elaboraÃÃo de um Plano de AÃÃo Governamental, construÃdo a partir de propostas negociadas entre esses trÃs atores, que incluÃa a retomada pelo Estado das terras devolutas estaduais em poder dos fazendeiros e o assentamento gradual das famÃlias acampadas. Esse Plano de AÃÃo que se pretendia pacificador deu inÃcio a uma espiral de conflitos e acordos que parecia tendente ao infinito. Num esforÃo de compreensÃo desse processo, a nova forma de aÃÃo estatal, iniciada com a experiÃncia de execuÃÃo do Plano, e as dinÃmicas sociais daà resultantes foram minuciosamente reconstruÃdas com recurso Ãs falas dos atores e imagens que retratam os principais episÃdios. A narrativa prossegue atà o ano de 1996, quando as primeiras mil famÃlias envolvidas naqueles conflitos comeÃam a ser assentadas em lotes definitivos e a situaÃÃo ganha ares de normalidade. O Plano de AÃÃo enfim cumpria seus objetivos de pacificaÃÃo. Ao final, o trabalho analisa os vÃrios planos em que esses conflitos se desenvolveram, com fatores relacionados simultaneamente a questÃes pessoais ou coletivas; aos aspectos de honra, prestÃgio e carisma; aos aspectos de poder econÃmico e polÃtico; aos valores e cÃdigos morais compartilhados nos grupos sociais; e aos jogos de cenas e espetÃculos voltados ao pÃblico externo, em que a imprensa exercia papel fundamental. Analisa tambÃm a aÃÃo de mediaÃÃo estatal desenvolvida, as prÃticas dos mediadores e os dilemas relacionados à dualidade do agente estatal na condiÃÃo de mediador-executor dos acordos referentes ao Plano de AÃÃo. Em conclusÃo, o trabalho apresenta algumas reflexÃes sobre as condiÃÃes de possibilidade de uma prÃtica estatal de mediaÃÃo de conflitos no Brasil. / Rural collective conflicts and agreements conceived to its pacification within a process of state mediation is the subject of the present work. It is introduced by the history of 150 years of frauds and illegal land appropriation in Pontal do Paranapanema, follows the landholders struggle of resistance transformation into huge land occupation process led by Movimento Sem-Terra (MST), within a collective conflict of great proportions, registered in national and international headlines in the 1995 news. Then, it traces a historical profile of the central social actors in field â landless workers, farmers and State agents â and rescues the circumstances that led to the construction of a Plan for Government Action, based on negotiated proposals among these three actors, which included the reclaiming of those land due to the State that were under the farmers possession, and the gradual settlement of the camped families. That Plan, intended to be peacemaker, started a spiral of conflicts and agreements that seemed to stretch till infinite. In the effort to understand this process, the new way of state action, initiated with the execution of that plan, and the resulting social dynamics, were reconstructed in its minor details, by the actors speeches and images that pictured the main episodes. The narrative goes on until the year of 1996, when the first thousand families that took place in those conflicts are definitively settled in rural settlement and the situation turns to normality. The Plan of Action fulfilled its objectives of pacification, at last. In the final part, the work analyses the several plans in which these conflicts were developed, with simultaneous factors related to personal and collective issues; to honor, prestige and charisma aspects; to economic and politic power aspects; to beliefs and moral codes shared by the social groups; and to the showing off and scenes directed to external public, when press acted key rule. It also analyses the action developed by state in mediation, the mediatorsâ practices and the dilemmas related to the duality of the state agent in the dual rule of mediator-executor of the agreements originated by the plan. In conclusion, the work presents some reflections about the conditions of possibility for a state practice in mediation on conflicts in Brazil.
504

Analyse comparative des conflits de lois et de juridictions relatifs au contrat d'assurance

Szabolcs, Nathalie 08 1900 (has links)
Ce mémoire porte sur l’étude des conflits de lois et de juridictions relatifs au contrat d’assurance. Le contrat d’assurance étant un contrat des plus usité, il est intéressant d’étudier, dans un contexte de mondialisation, de globalisation des échanges, de ce qu’il en advient du contrat d’assurance dans le cadre des relations privées à caractère international. En ce sens, seront traitées des règles de conflit de lois et de juridictions relatifs au contrat d’assurance dans le cadre des instruments que sont le Règlement Rome I, le Règlement Bruxelles I Bis et la Convention de Lugano, mais également, dans celui du droit international privé québécois. Ce sera donc une approche de droit comparé qui sera adoptée au travers de cette étude. L’on verra notamment que le contrat d’assurance a donné lieu à divers traitements méthodologiques du point de vue de la résolution des conflits de lois et de juridictions. Il sera donc intéressant de comparer ces approches afin de déterminer celle qui pourrait atteindre au mieux les objectifs spécifiques du contrat d’assurance, à savoir, notamment, celui de protection de la partie faible. / This thesis is concerned with the study of the conflicts of laws and jurisdictions relating to the insurance contract. Since insurance contracts are a type of contract that is commonly used, it is worth understanding, notably in the context of economic globalization, what specifically happens to the contract of insurance within the framework of international private relations. In this sense, the rules of conflict of laws and jurisdictions relating to the insurance contract will be considered with regards to the framework of the Rome I Regulation, the Brussels I Bis Regulation and the Lugano Convention, as well as with respect to the private international law of Quebec. Therefore, a comparative law approach will be adopted through this study. It will be noticed among other things that the insurance contract has given rise to various methodological treatments with regards to the resolution of conflicts of laws and jurisdictions. It will therefore be interesting to compare these approaches in order to determine which approach could best achieve the specific objectives of the insurance contract, in particularly, the protection of the weaker party.
505

The Dynamics of Workplace Conflicts / The Unfolding of Task Conflicts and Possibilities to Counteract Their Negative Effects

Mauersberger, Heidi 21 October 2020 (has links)
Konflikte am Arbeitsplatz sind allgegenwärtig–sie erschweren den Berufsalltag und können schlimmstenfalls auch zu privaten Problemen führen. Dennoch ist unklar, wie genau Aufgabenkonflikte das Wohlbefinden und die Leistungsfähigkeit von Beschäftigten beeinflussen. Mechanismen, wann und warum Aufgabenkonflikte negative Folgen haben, wurde bisher wenig erforscht. Begründet werden kann dies damit, dass Aufgabenkonflikte bisher zumeist in Feldstudien mittels retrospektiven (und zudem subjektiven) Momentaufnahmen untersucht wurden. Das erste Ziel meines Vorhabens war es demnach, Aufgabenkonflikte in einer Tagebuchstudie sowie in einem kontrollierten Setting im Labor zu untersuchen, um deren emotionale und kognitive Konsequenzen präzise und unmittelbar zu erfassen. Weiterhin haben bisherige Studien größtenteils situative Faktoren untersucht und persönliche Charakteristiken, die ebenfalls die Bewertung von Aufgabenkonflikten beeinflussen, außer Acht gelassen. Daher verfolgte ich als zweites Ziel eine ganzheitliche Sichtweise auf den Aufgabenkonflikt einzunehmen. Dafür explorierte ich, ob Unterschiede zwischen Personen emotionale Mimikry zu zeigen (d.h. die Emotionen anderer zu spiegeln) einen Einfluss auf die Beurteilung von Aufgabenkonflikten haben. Um das Bild auf Aufgabenkonflikte zu komplementieren bestand mein finales Ziel darin, die Wirksamkeit einer Intervention zur Abschwächung von Konfliktkonsequenzen zu untersuchen. Hierfür wählte ich eine allgemein bekannte Strategie der kognitiven Umbewertung („Reappraisal") und prüfte, ob diese Strategie einen Aufgabenkonflikt als weniger emotional aufreibend und somit weniger destruktiv erscheinen lässt. Durch die Integration von vier empirischen Studien, die in renommierten psychologischen Zeitschriften publiziert wurden, leistet meine Dissertationsschrift einen Beitrag dazu, die von Konflikten am Arbeitsplatz ausgehenden komplexen Wirkweisen besser zu verstehen, sowie Möglichkeiten aufzuzeigen Konfliktkonsequenzen zu modifizieren. / Workplace conflicts have been widely recognized as a core social stressor across occupations with detrimental effects for employees’ task progress and employees’ general stress levels and health. Yet, the presumed destructive effects of task conflicts on employee outcomes, such as well-being and performance, have not been confirmed consistently. Further, the fine-grained mechanisms that explain the effects of task conflicts on employee outcomes have not been fully explored yet. This may be because most previous research relied on retrospective self-reports and the complex nature of task conflicts and their multiple emotional and cognitive consequences are difficult to disentangle in cross-sectional field studies. The first aim of my thesis was to examine the short-term effects of task conflicts by measuring conflicts using a diary approach with event-sampling methodology in the field (Study 1) and by inducing conflicts under controlled circumstances in the laboratory (Study 2). Further, previous studies mostly investigated the effects of the conflict situation on health and productivity outcomes. Hence, my second aim was to identify participant characteristics that influence the conflict evaluation in addition to the characteristics of the situation. In Study 3, we explored whether individual differences in emotional mimicry (i.e., the imitation of emotions of others) affect the evaluation of task conflicts. Finally, my last aim was to seek for strategies that help to buffer the negative effects of task conflicts. Hence, in Study 4, we investigated the effectiveness of a conflict re-evaluation (i.e., reappraisal) intervention on several (objective) indices of negative affect. Insights gained from these four studies give a more precise picture of the nature of workplace conflicts and of the modifiability of their consequences.
506

Understanding sources of conflict between landlords and tenants in Kenya

Kinyua, Frederick Joses 09 April 2009 (has links)
No description available.
507

Conflict in perpetuity? Examining Zimbabwe’s protracted social conflict through the lens of land reform

Sims, Bryan M. 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: This dissertation analyses the relationship between civil society and political leadership within the context of Zimbabwe’s protracted social conflict, particularly through the lens of land policy. Through the use of strategic informants, it yields important insights into the origins, form and impact of political leadership and civil society in a way that will expose the dynamics of elite and grassroots mobilisation and the political context in which land policy is either made or obstructed. Specifically, this dissertation examines two research questions. First, if political leadership is not representative of the citizenry, is land policy more likely to engender overt conflict? Second, if civil society has an autonomous role in the public sphere, is land policy more likely to benefit citizens? This dissertation also confronts an emerging empirical problem: the absence of descriptive data in regards to how civil society and political leadership have engaged in reforming land policy in Zimbabwe during the period of transition from 2008 to 2013. By measuring representation and autonomy – indicators of human needs satisfaction– this dissertation traced each phase of the protracted social conflict as it both helped to create the conditions for a liberation model of representation while simultaneously further exacerbating protracted social conflict within Zimbabwe. / AFRIKAANSE OPSOMMING: Hierdie tesis ontleed die verhouding tussen die burgerlike samelewing en politieke leierskap veral deur die lens van grondbeleid, binne die konteks van Zimbabwe se uitgerekte sosiale konflik. Dit het ten doel om belangrike insigte op te lewer in die oorsprong, vorm en impak van politieke leierskap en die burgerlike samelewing. Die word blootgestel in 'n manier wat die dinamika van die elite en mobilisering op grondvlak in ag neem soweel as die politieke konteks waarin grondbeleid óf gemaak is of belemmer word. Hierdie tesis konfronteer ook 'n opkomende empiriese probleem: die afwesigheid van beskrywende data met betrekking tot die betrokkenheod van die burgerlike samelewing en politieke leierskap tydens die grondhervorming proses in Zimbabwe gedurende die tydperk van oorgang tussen 2008 en 2013. Deur die meting van verteenwoordiging en outonomie - aanwysers van menslike behoeftes bevrediging - word elke fase van die uitgerekte sosiale konflik ondersoek met betrekking tot hoe ‘n bevryding model van verteenwoordigheid beide gehelp het om die voorwaardes te skepvir die eindeiging van die PSC; maar terselfdertyd het dit ook die sosiale konflik in Zimbabwe verder uitgerek. !
508

我國立法委員利益迴避制度之研究

王正海, Wang,Cheng-Hai Unknown Date (has links)
倫理是有關哲學、價值及道德的研究,涉及判斷力和行為的準則,亦或是藉以建立及執行正確而又適當行為的樣準;決策則是公共行政內容中最主要的活動,公共政策本身即含有決定社會價值再分配的特性;民主國家的立法單位正是決定利益歸屬的關鍵場域,作為立法機關構成者的立法委員對倫理的認知及踐履,將反映在當代政治風氣的清明與否,利益的分配是否合於公眾對公平正義的期待?長久以來,民眾對立法院形象評價低落的原因之一,正在於部分立法委員以權牟私,特權關說等等不符倫理行為導致政治活動商業化的情事浮濫,故及早建立外部的行為規範,督促政治風氣及國會倫理趨於清明,並設置有效的監督機制,是當前國會改革工程極為艱鉅的工程。 國會的改革與政治環境關係密不可分,故本研究擬採制度比較的方法切入,主要試圖勾勒:(一)、立法委員行為與倫理對公益的關係及影響?(二)、在比較及分析我國國會利益迴避制度的同時,亦參酌美、日、英等國對國會的利益迴避制度,並比較和我國現有制度的異同?(三)、經由現正研擬中有關於利益迴避制度的分析研究,歸納出未來對立法委員行為規範的立法趨勢為何?(四)、整合前述各項差異,歸納出可能改進的方向,作為利益迴避在國會倫理法制化過程中改進的參考。 關鍵字:立法委員、利益迴避、國會倫理 / Ethics deals with value, morality, and philosophy, involving judgment and behavioral principles; it may also be the criteria for establishment and guidance of right and proper conduct. Decision-making is a primary activity of public administration and decision-making itself contains redistributive characteristics of social value. In democratic nations, legislative bodies are the key field that decides whom interests belong to. Being legislative bodies, their acknowledgement and observation of ethics may reflect whether current political atmosphere is free of corruption or not and distribution of interests meets public expectation of fairness and justice. For a long time, one of the reasons that the public rates the Legislative Yuan low lies in that legislators abuse their power to pursue their own interests as influence peddlers; this conduct is not ethical and leads to indiscriminate commercialization of political activities. Hence, setting external conduct norms as soon as possible, enforcing cleanness of political atmosphere and legislative ethics, and forming effective supervising organizations are arduous work for reforming the Legislative Yuan at present. Reformation of the Legislative Yuan and political circumstances are closely related; therefore, this study starts at comparison of system methods in an attempt to present an account: (1) What is the relations and influences of legislators’ conduct and ethics over public interests? (2) By comparison and analysis of the Legislative Yuan’s conflicts of interests and by reference to conflicts of interests systems in Britain, Japan, and U.S.A. this study tries to compare and distinguish differences in these systems. (3) On analysis and study of conflicts of interests system being prepared, legislation trends of legislators conduct norms can be concluded. (4) To summarize the above-mentioned differences, improvements are summed up for legislation for conflicts of interests in legislative ethics code as reference. Key word: legislators, conflicts of interests, Legislative Yuan’s ethics.
509

會計師與律師對職業道德之認知差異 / The study of the perception gaps of professional ethics between certified public accountants and lawyers

劉子珈, Liu, Tze Chia Unknown Date (has links)
本研究旨在探討會計師與律師二種專門職業人員對職業道德的認知程度及差異情形。本研究採用多元道德量表作為道德判斷之衡量工具,配合四個道德情境故事,以問卷調查方式向會計師事務所及律師事務所蒐集樣本資料,回收194份問卷,有效問卷173份,並以敘述性統計、t 檢定、Spearman相關分析等方法進行資料分析。實證結果發現,會計師對獨立性與律師對避免利益衝突的認知上有顯著差異,而二者對保密的認知則無顯著差異,可能係此二種專門職業之職業特性不同所致。根據研究結果,本研究提出相關建議,供實務界、教育界及後續研究者作為參考。 / The main purposes of this study were to explore the ethical perception gaps of professional ethics between Certified Public Accountants and Lawyers. This research uses multidimensional ethics scale as a measurement of moral judgments with four dilemmas, then uses the method of questionnaire survey with participants in some accounting firms and law firms. There are 194 samples retrieved, and 174 effective samples. The data is analyzed by using the method of descriptive statistics, t-test, Spearman’s correlation. The findings of the study revealed that the perception gaps of independence for accountants and avoiding the conflicts of interests for lawyers are significant, and the perception gaps of confidentiality are insignificant. This might be resulted from the particularity of these two professions. As a result, this study is recommendable for practicing field, educators, and future researcher as reference materials.
510

Evolution de la composition génétique du tissu nourricier de la graine : Double fécondation, polysporie et empreinte parentale / Evolution of the genetic make-up of seed nutritives tissues

Cailleau, Aurélie 13 December 2010 (has links)
Chez les plantes à graine, l'albumen est un tissu nourricier surprenant, puisqu'il résulte de la double fécondation, qui est la fécondation concomitante de l'oosphère d'une part, et de la cellule mère de l'albumen, la cellule centrale, d'autre part. Dans cette thèse, nous étudions les pressions de sélection qui déterminent l'évolution de l'albumen et pourraient expliquer l'évolution (1) de la double fécondation, (2) d'un doublement des contributions maternelles dans la cellule centrale, (3) de la polysporie, qui consiste en la participation de plusieurs produits de méiose à la formation du gamétophyte, et (4) de l'empreinte parentale, l'expression différentielle des allèles maternels et paternels.Ces innovations modifient l'hétérozygotie dans le tissu nourricier et par conséquent, ont le potentiel de changer l'hétérosis de la graine. Dans cette thèse, nous commençons par étudier comment les changements génétiques qui découlent de la double fécondation, du doublement des contributions maternelles, de la polysporie et de l'empreinte parentale modifient l'hétérosis, ce qui peut jouer en faveur ou en défaveur de leurs évolutions. Puis, nous faisons une revue des données disponibles dans la littérature pour tester si ces traits sont le résultat d'un conflit mâle-femelle sur l'allocation des ressources. Enfin, nous étudions de manière expérimentale les patrons de l'allocation des ressources chez le maïs, pour tester si les embryons sont en compétition pour les ressources, ce qui est une des conditions nécessaires pour qu'un conflit sur l'allocation des ressources ait lieu.Nos modèles théoriques nous permettent de décrire un conflit mâle-femelle sur l'exposition des allèles délétères dans les tissus pour lesquels l'expression des gènes est asymétrique. Ce conflit n'avait jamais été décrit auparavant, et ouvre de nouvelles perspectives pour la compréhension de l'évolution de l'expression génétique. L'analyse des données indique que les théories alternatives à la théorie du conflit sur l'allocation des ressources ont parfois un bon pouvoir explicatif, et méritent par conséquent d'être d'avantage explorées. Enfin, notre étude expérimentale sur le maïs montre que la compétition entre embryons est prédominante lors de l'allocation des ressources chez cette espèce, ce qui est concordant avec les prédictions de la théorie du conflit sur l'allocation. / In seed plants, the endosperm is a surprising nutritive tissue, because it results from double fertilization, an eccentricity which results from the parallel fertilization of the egg cell on the one hand, and of the mother cell of the endosperm, the central cell, on the other hand. In this thesis, we study the selective pressures which drive the evolution of the endosperm and may explain the evolution of (1) double fertilization, (2) a doubling of maternal contributions in the central cell, (3) polyspory, the participation of several meiotic products to the gametophyte and (4) imprinting, the differential expression of maternal and paternal alleles. These innovations modify heterozygosity in the endosperm and as a consequence, have the potential to change heterosis in the seed. In this thesis, we first investigate how genetic changes that result from double fertilization, doubling of maternal contribution, polyspory and imprinting modify heterosis, which may play in favour or against the evolution of these traits. Second, we review the available data to test whether these traits are the result of a male-female conflict over resource allocation. Finally, we study experimentally patterns of resource allocation in maize to assess whether embryos compete for resources, which is a necessary condition for the conflict over resource allocation to occur. Our theoretical models allow us to describe a male-female conflict over the exposition of deleterious alleles in tissues with asymmetrical gene expression. This conflict had never been described before and opens perspectives for understanding the evolution of gene expression. We conclude from our analysis of data that theories which are alternative to the conflict theory over resource allocation may have a better explanatory power and therefore deserve to be further explored. Finally, our experimental study in maize shows that competition between embryos drives resource allocation in this species, which is consistent with predictions of the conflict over resource allocation theory.

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