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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.
71

Energetic processes driving potential peptide protometabolisms at the origin of living systems / Processus énergétiques gouvernant des protométabolismes peptidiques à l’origine des systèmes vivants

Ajram, Ghinwa 29 November 2018 (has links)
La thèse aborde différentes questions de chimie prébiotique dans le contexte de l’origine de la vie par une approche de chimie systémique. La première partie est dédiée à l’étude de processus d’activation chimique important non seulement pour la formation de polymères, mais aussi pour alimenter le système en énergie de manière à le maintenir dans un état éloigné de l’équilibre, un prérequis pour l’auto-organisation. Il a été suggéré que les intermédiaires 5(4H)-oxazolones formés par l’activation de l’extrémité C-terminale des peptides pourrait être impliquée dans l’auto-organisation du vivant. Dans ce but, nous avons évalué la réactivité de réactifs pertinents dans un contexte prébiotique et décrits dans la littérature comme capables d’activer des acides α-aminés. Aucun d’entre eux n’a manifesté une activité satisfaisante pour l’activation C-terminale des peptides, montrant qu’une voie possible pour alimenter un protométabolisme des peptides en énergie n’est pas identifiée à ce jour à l’exception notable des N-carboxyanhydrides (NCA) qui peuvent être formé par des voies prébiotiquement plausibles. Nous avons par ailleurs démontré que les carbodiimides sont aussi efficaces pour l’activation des N-carbamoylamino acides que pour celle du carboxyle terminal des peptides en milieu aqueux dilué. La seconde partie du document expose de nouveaux résultats en faveur d’un processus de coévolution peptides-nucléotides. D’abord, une étude de la réactivité d’agents d’aminoacylation de l’extrémité 3’ de l’ARN est présentée. Ensuite, nous évaluons des co-polymères acides α-aminés-nucléotides liés par des enchaînements phosphoramidate et esters comme partenaires éventuels de l’évolution chimique. La pertinence cinétique de ces structures est démontrée ainsi que des voies chimiques permettant leur formation. / The thesis addresses several issues in prebiotic chemistry in the context of the origins of life through a systems chemistry approach. The first part is devoted to the study of chemical activation processes that are not only important in the formation of polymers, but also to feed the system with energy in order that a far from equilibrium state is maintained, a prerequisite for self-organization. It has been suggested that 5(4H)-oxazolones intermediates formed by C-terminus peptide activation could be involved in self-organization of life. To this aim, we have checked the reactivity of relevant prebiotic reagents previously proposed to activate α-amino acids. None of them led to a satisfactory C-terminus activation of peptides, showing that no general process for feeding a protometabolism of peptides with energy is identified yet, with the notable exception of N-carboxyanhydrides (NCAs) that can be formed through prebiotically relevant pathways. Additionally, we demonstrated that carbodiimides reagents are as efficient in the activation of N-carbamoyl amino acids as in that of the C-terminus of peptides in diluted aqueous media. The second part of the dissertation discloses new results in support of a process of coevolution of peptides and nucleotides. Firstly, a study of non-enzymatic aminoacylation reagents of the 3’-terminus of RNA is presented. Secondly, we assessed co-polymers of α-amino acids and nucleotides bound by phosphoramidate and ester linkages as potential players in chemical evolution. The kinetic relevance of these structures was demonstrated as well as potential chemical processes that allow their formation.
72

PCAISO-GT: uma metaheurística co-evolutiva paralela de otimização aplicada ao problema de alocação de berços

Oliveira, Carlos Eduardo de Jesus Guimarães 24 March 2013 (has links)
Submitted by Maicon Juliano Schmidt (maicons) on 2015-03-30T11:51:21Z No. of bitstreams: 1 Carlos Eduardo de Jesus Guimarães Oliveira.pdf: 1236896 bytes, checksum: ef9d04e6f25aee7908b56a622411bc74 (MD5) / Made available in DSpace on 2015-03-30T11:51:21Z (GMT). No. of bitstreams: 1 Carlos Eduardo de Jesus Guimarães Oliveira.pdf: 1236896 bytes, checksum: ef9d04e6f25aee7908b56a622411bc74 (MD5) Previous issue date: 2014-01-31 / Nenhuma / Este trabalho apresenta um algoritmo de otimização baseado na metaheurística dos Sistemas Imunológicos Artificiais, princípios de Teoria dos Jogos, Co-evolução e Paralelização. Busca-se a combinação adequada dos conceitos de Teoria dos Jogos, Co-evolução e Paralelização aplicados ao algoritmo AISO (Artificial Immune System Optimization) para resolução do Problema de Alocação de Berços (PAB). Dessa maneira, o algoritmo é formalizado a partir das técnicas citadas, formando o PCAISO-GT: Parallel Coevolutionary Artificial Immune System Optimization with Game Theory. Inicialmente, foram realizados experimentos visando à sintonia dos parâmetros empregados nas diferentes versões da ferramenta desenvolvida. Com base nas melhores configurações identificadas, foram realizados experimentos de avaliação através da solução de um conjunto de instâncias do PAB. Os resultados obtidos permitiram a indicação da versão co-evolutiva associada à teoria dos jogos como a melhor para solução do problema em estudo. / This paper presents an optimization algorithm based on metaheuristic of Artificial Immune Systems, principles of Game Theory, Co-evolution and parallelization. The objective is find the appropriate combination of the concepts of Game Theory, Co-evolution and Parallelization applied to AISO algorithm (Artificial Immune System Optimization) for solving the Berth Allocation Problem (BAP). Thus, the algorithm is formalized from the above mentioned techniques, forming the PCAISO-GT: Parallel Coevolutionary Artificial Immune System Optimization with Game Theory. Initially, experiments aiming to tune the parameters were performed using different versions of the tool developed. Based on the identified best settings, evaluation experiments were carried out by solving a set of instances of the PAB. The results obtained allowed the appointment of co-evolutionary version associated with game theory as the best solution to the problem under study.
73

A coevolução no problema de design

Souza, Débora de Oliveira Lemos Rocha de 27 March 2015 (has links)
Submitted by Maicon Juliano Schmidt (maicons) on 2015-06-11T19:24:34Z No. of bitstreams: 1 Débora de Oliveira Lemos Rocha de Souza.pdf: 11262812 bytes, checksum: 1afc26309c47e8dc71f1c5e88aae7409 (MD5) / Made available in DSpace on 2015-06-11T19:24:34Z (GMT). No. of bitstreams: 1 Débora de Oliveira Lemos Rocha de Souza.pdf: 11262812 bytes, checksum: 1afc26309c47e8dc71f1c5e88aae7409 (MD5) Previous issue date: 2015-03-27 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / FAPERGS - Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul / Algumas ações do processo projetual se restringem aos pensamentos dos designers, gerando uma dificuldade para compreender o processo e torná-lo explícito. As pesquisas nessa área tentam transpor essas limitações, buscando perceber o modo como os designers resolvem os problemas para aprimorar a sua atuação. Esses problemas são caracterizados como mal-estruturados e podem ser vistos de diferentes perspectivas, gerando respostas distintas. O conceito de coevolução percebe a resolução de problemas de forma evolutiva: à medida que compreende-se um pouco mais o problema, as respostas tornam-se mais aprimoradas. Esta dissertação tem como objetivo geral compreender a coevolução do problema de design. Para isso, realizou-se uma pesquisa exploratória em um workshop em design, coletando as informações por meio de grupos focais e do registro, em vídeo, do processo realizado pelos participantes. A técnica utilizada para analisar as informações coletadas nos grupos focais e nos vídeos foi a análise de conteúdo, com algumas adaptações necessárias à pesquisa realizada. Na análise, percebeu-se que a coevolução é influenciada: 1) pela formulação inicial do problema que funciona como uma força motora, impulsionando o processo de resolução do problema; 2) pela forma como as equipes se articulam, levando-se em conta o modo como os integrantes desempenham diferentes papeis e estabelecem um ritmo de resolução do problema de acordo com experiências anteriores que trazem para o projeto; 3) pelos questionamentos em relação ao problema ou à solução, caracterizando-se como uma das estratégias utilizadas pelos designers para avançar no espaço-problema ou no espaço-solução. Concluiu-se, assim, que não só o espaço-problema e o espaço-solução se modificam no percurso do projeto de forma a provocar uma evolução mútua, mas os diversos fatores que envolvem o processo projetual também influenciam na coevolução do problema de design. / Some actions in the design process are restricted to the designers’ thoughts, what may cause some difficulties in understanding the process itself and making it explicit. Studies in this area attempt to overcome these limitations by looking into the way designers solve problems to improve their performance. These problems are usually characterized as ill-structured and can be seen from different perspectives, leading to distinct answers. The concept of co-evolution regards problem resolution in an evolutive manner: as the problem is better understood, the answers become more refined. The overall objective of this work is to understand the co-evolution of the design problem. In order to do this, an exploratory research was conducted within a design workshop, where data was collected by means of both focal groups and videos recording the participants’ process. The technique used to analyse all this data was Content Analysis, with some necessary adaptations to the context of the present research. In the analysis, it was possible to observe that co-evolution is influenced by: 1) the initial formulation of the problem that works as a driving force, boosting the problem resolution process; 2) the way the groups manage themselves, taking into consideration the manner in which different members play distinct roles and establish a problem resolution pace based on previous experiences they bring to the project; and 3) inquiries related to the problem or the solution, which can be regarded as one of the strategies used by designers to move forward into the problem space or the solution space. In conclusion, all these observations lead to the understanding that not only the problem space and the solution space modify themselves in the course of the project, triggering mutual evolution, but the diverse aspects involved in the design context also have some influence on the co-evolution of the design problem.
74

Pareto multi-objective evolution of legged embodied organisms

Teo, Jason T. W., Information Technology & Electrical Engineering, Australian Defence Force Academy, UNSW January 2003 (has links)
The automatic synthesis of embodied creatures through artificial evolution has become a key area of research in robotics, artificial life and the cognitive sciences. However, the research has mainly focused on genetic encodings and fitness functions. Considerably less has been said about the role of controllers and how they affect the evolution of morphologies and behaviors in artificial creatures. Furthermore, the evolutionary algorithms used to evolve the controllers and morphologies are pre-dominantly based on a single objective or a weighted combination of multiple objectives, and a large majority of the behaviors evolved are for wheeled or abstract artifacts. In this thesis, we present a systematic study of evolving artificial neural network (ANN) controllers for the legged locomotion of embodied organisms. A virtual but physically accurate world is used to simulate the evolution of locomotion behavior in a quadruped creature. An algorithm using a self-adaptive Pareto multi-objective evolutionary optimization approach is developed. The experiments are designed to address five research aims investigating: (1) the search space characteristics associated with four classes of ANNs with different connectivity types, (2) the effect of selection pressure from a self-adaptive Pareto approach on the nature of the locomotion behavior and capacity (VC-dimension) of the ANN controller generated, (3) the effciency of the proposed approach against more conventional methods of evolutionary optimization in terms of computational cost and quality of solutions, (4) a multi-objective approach towards the comparison of evolved creature complexities, (5) the impact of relaxing certain morphological constraints on evolving locomotion controllers. The results showed that: (1) the search space is highly heterogeneous with both rugged and smooth landscape regions, (2) pure reactive controllers not requiring any hidden layer transformations were able to produce sufficiently good legged locomotion, (3) the proposed approach yielded competitive locomotion controllers while requiring significantly less computational cost, (4) multi-objectivity provided a practical and mathematically-founded methodology for comparing the complexities of evolved creatures, (5) co-evolution of morphology and mind produced significantly different creature designs that were able to generate similarly good locomotion behaviors. These findings attest that a Pareto multi-objective paradigm can spawn highly beneficial robotics and virtual reality applications.
75

An experimental evaluation of resource allocation in island plants with respect to their invertebrate herbivores

Kay, M. K. (Nod) January 2008 (has links)
New Zealand’s isolation and periods of marine transgression have limited its biota to an extent which can be considered depauperate, even by island standards. Endemic vertebrates are rare and prominent invertebrate families, such as the renowned forest defoliators of the Lymantriidae, are absent. The proven vulnerability of the flora to introduced vertebrates reaffirms a belief in the invasiveness of islands and fuels the contingency plans aimed at averting similar devastation from further alien invertebrate defoliators. Nothofagus is a dominant element of the climax forests of New Zealand and the larger landmasses bordering the South Pacific Ocean. Assessments of the resistance to defoliation of continental and New Zealand species of Nothofagus, and a range of other forest genera endemic to New Zealand, was undertaken using bioassays of naïve polyphagous defoliators. The bioassays were undertaken in Europe, utilising gypsy moth, Lymantria dispar (Lepidoptera: Lymantriidae) and the fall webworm, Hyphantria cunea (Lepidoptera: Arctiidae) as defoliators, fed foliage plants growing in European arboreta. In New Zealand, bioassays utilised Australian painted apple moth, Teia anartoides (Lepidoptera: Lymantriidae) and tree species from local arboreta, gardens and natural populations. Larval growth rate was the primary parameter recorded to assess plant resistance. The relevance of growth rate was investigated by comparison with other recorded parameters and resistance to a surrogate pathogen, in the form of commercially available bio-insecticide. Larval growth rate was positively correlated with survivorship, potential fecundity, mating success and resistance to disease. The growth rate of larvae fed Nothofagus was positively correlated to the species-specific leaf nitrogen content. The results of the bioassays showed that despite the accepted paradigms, New Zealand’s flora was largely resistant to exotic defoliators. As an explanation of this apparent anomaly, the Island Resource Allocation (IRA) hypothesis was developed and posits that ‘the palatability iv of a plant to invertebrate herbivores is proportional to the geographic range of the plant’. The basis for the IRA hypothesis proposes a redefinition of the fundamental ecological principle of the species: area relationship. Islands, or similarly geographically constrained ecosystems, which support lower biodiversity, have impoverished trophic levels and consequently have weaker top-down regulation of herbivores by natural enemies. The IRA hypothesis argues that island ecosystem stability is achieved through the bottom-up process of plant defence. The IRA hypothesis was tested intra-specifically using bioassays using painted apple moth in which larvae were offered foliage of specimens from naturally discontinuous populations of Nothofagus truncata. The results supported the hypothesis in that the smallest populations of N. truncata exhibited the greatest resistance to the defoliator. The IRA hypothesis and a demonstrated mechanism for a differential resistance in Nothofagus species could resolve a number of enduring debates in ecology. Habitat area appears to explain the relative strengths of top-down and bottom-up regulation of herbivores. It also predicts the strengths of reciprocal evolution within the geographic mosaic of co-evolution and highlights the influence of biodiversity in invasive ecology. It may also help to resolve the contentious and extremely relevant debate of the role of biodiversity in ecosystem function.
76

Autonomous Systems in Society and War : Philosophical Inquiries

Johansson, Linda January 2013 (has links)
The overall aim of this thesis is to look at some philosophical issues surrounding autonomous systems in society and war. These issues can be divided into three main categories. The first, discussed in papers I and II, concerns ethical issues surrounding the use of autonomous systems – where the focus in this thesis is on military robots. The second issue, discussed in paper III, concerns how to make sure that advanced robots behave ethically adequate. The third issue, discussed in papers IV and V, has to do with agency and responsibility. Another issue, somewhat aside from the philosophical, has to do with coping with future technologies, and developing methods for dealing with potentially disruptive technologies. This is discussed in papers VI and VII. Paper I systemizes some ethical issues surrounding the use of UAVs in war, with the laws of war as a backdrop. It is suggested that the laws of war are too wide and might be interpreted differently depending on which normative moral theory is used. Paper II is about future, more advanced autonomous robots, and whether the use of such robots can undermine the justification for killing in war. The suggestion is that this justification is substantially undermined if robots are used to replace humans to a high extent. Papers I and II both suggest revisions or additions to the laws or war. Paper III provides a discussion on one normative moral theory – ethics of care – connected to care robots. The aim is twofold: first, to provide a plausible and ethically relevant interpretation of the key term care in ethics of care, and second, to discuss whether ethics of care may be a suitable theory to implement in care robots. Paper IV discusses robots connected to agency and responsibility, with a focus on consciousness. The paper has a functionalistic approach, and it is suggested that robots should be considered agents if they can behave as if they are, in a moral Turing test. Paper V is also about robots and agency, but with a focus on free will. The main question is whether robots can have free will in the same sense as we consider humans to have free will when holding them responsible for their actions in a court of law. It is argued that autonomy with respect to norms is crucial for the agency of robots. Paper VI investigates the assessment of socially disruptive technological change. The coevolution of society and potentially disruptive technolgies makes decision-guidance on such technologies difficult. Four basic principles are proposed for such decision guidance, involving interdisciplinary and participatory elements. Paper VII applies the results from paper VI – and a workshop – to autonomous systems, a potentially disruptive technology. A method for dealing with potentially disruptive technolgies is developed in the paper. / <p>QC 20130911</p>
77

A Complex Co-Evolutionary Systems Approach to the Management of Sustainable Grasslands: A Case Study in Mexico

Martinez-Garcia, Alejandro N. Unknown Date (has links)
The complex co-evolutionary systems approach (CCeSA) provides a well-suited framework for analysing agricultural systems, serving as a bridge between biophysical and socioeconomic sciences, allowing for the explanation of phenomena, and for the use of metaphors for thinking and action. By studying agricultural systems as self-generated, hierarchical, complex co-evolutionary farming systems (CCeFSs), one can investigate the interconnections between the elements that constitute CCeFSs, along with the relationships between CCeFSs and other systems, as a fundamental step to understanding sustainability as an emergent property of the system. CCeFSs are defined as human activity systems emerging from the purposes, gestalt, mental models, history and weltanschauung of the farm manager, and from his dynamic co-evolution with the environment while managing the resources at his hand to achieve his own multiple, conflicting, dynamic, semi-structured and constrained purposes. A sustainable CCeFS is described as one that exhibits both enough fitness to achieve its multiple, dynamic, constrained, semi-structured, and often incommensurable and conflicting purposes while performing above threshold values for failure, and enough flexibility to dynamically co-evolve with its changing biophysical and socioeconomic environment for a given future period. Fitness and flexibility are essential features of sustainable CCeFSs because they describe the systems' dynamic capacity to explore and exploit its dynamic phase space while co-evolving with it. This implies that a sustainable CCeFS is conceived as a set of dynamic, co-evolutionary processes, contrasting with the standard view of sustainability as an equilibrium or steady state. Achieving sustainable CCeFSs is a semi-structured, constrained, multi-objective, and dynamic optimisation management problem with an intractable search phase space, that can be solved within the CCeSA with the help of a multi-objective co-evolutionary optimisation tool. Carnico-ICSPEA2, a Co-Evolutionary Navigator (CoEvoNav) used as a CCeSA's tool for harnessing the complexity of the CCeFS of interest and its environment towards sustainability, is introduced. The software was designed by its end-user - the farm manager and author of this thesis - as an aid for the analysis and optimisation of the "San Francisco" ranch, a beef cattle enterprise running on temperate pastures and fodder crops in the central plateau of Mexico. By combining a non-linear simulator and a multi-objective evolutionary algorithm with a deterministic and stochastic framework, the CoEvoNav imitates the co-evolutionary pattern of the CCeFS of interest. As such, the software was used by the farm manager to "navigate" through his CCeFS's co-evolutionary phase space towards achieving sustainability at farm level. The ultimate goal was to enhance the farm manager's decision-making process and co-evolutionary skills, through an increased understanding of his system, the co-evolutionary process between his mental models, the CCeFS, and the CoEvoNav, and the continuous discovery of new, improved sets of heuristics. An overview of the methodological, theoretical and philosophical framework of the thesis is introduced. Also, a survey of the Mexican economy, its agricultural sector, and a statistical review of the Mexican beef industry are presented. Concepts such as modern agriculture, the reductionist approach to agricultural research, models, the system's environment, sustainability, conventional and sustainable agriculture, complexity, evolution, simulators, and multi-objective optimization tools are extensively reviewed. Issues concerning the impossibility of predicting the long-term, detailed future behaviour of CCeFSs, along with the use of simulators as decision support tools in the quest for sustainable CCeFSs, are discussed. The rationale behind the simulator used for this study, along with that of the multi-objective evolutionary tools used as the makeup of Carnico-ICSPEA2, are explained. A description of the "San Francisco" ranch, its key on-farm sustainability indicators in the form of objective functions, constraints, and decision variables, and the semi-structured, multi-objective, dynamic, constrained management problem posed by the farm manager's planned introduction of a herd of bulls for fattening as a way to increase the fitness of his CCeFS via a better management of the system's feed surpluses and the acquisition of a new pick-up truck are described as a case study. The tested scenario and the experimental design for the simulations are presented as well. Results from using the CoEvoNav as the farm manager's extended phenotype to solve his multi-objective optimisation problem are described, along with the implications for the management and sustainability of the CCeFS. Finally, the approach and tools developed are evaluated, and the progress made in relation to methodological, theoretical, philosophical and conceptual notions is reviewed along with some future topics for research.
78

Abordagem co-evolutiva hierárquica para geração automática de sistemas nebulosos.

Talon, Anderson Francisco 13 September 2006 (has links)
Made available in DSpace on 2016-06-02T19:05:22Z (GMT). No. of bitstreams: 1 DissAFT.pdf: 987671 bytes, checksum: a50597a438e0122d6e69ee6481e7d4a3 (MD5) Previous issue date: 2006-09-13 / This work focuses on the problem of automatic generation of fuzzy systems through evolutionary computation, specifically using the approach of co-evolution. Coevolution is based on the idea of modular modeling of the problem subcomponents. In this work the subcomponents are represented by different species, which have a collaborative relation among them. The fuzzy system to be created has the objective of pattern classification. Basically, the evolutionary scheme is composed by four different species, which have a hierarchical collaboration both in the generation of the species and in the fitness determination of the individuals of these species. These species are organized in levels, where the contribution in the species generation happens from the lowest to highest levels and the contribution in the fitness determination happens from the highest to lowest levels. The results obtained indicate that the studied approach is very promising and, through its use, one can generate efficient classification systems, that present a performance similar to other approaches found in the literature. / Este trabalho enfoca o problema de geração automática de sistemas nebulosos por meio da computação evolutiva, mais especificamente por meio da abordagem de coevolução. A co-evolução baseia-se na idéia de modelagem modular de subcomponentes do problema. Neste trabalho esses subcomponentes são representados por espécies diferentes, que têm uma relação colaborativa entre si. Essa relação força uma evolução co-adaptada entre as populações das espécies. O sistema nebuloso a ser gerado tem como objetivo a classificação de padrões. Basicamente, o esquema evolutivo é formado por quatro espécies diferentes, que têm uma colaboração hierárquica, tanto na geração das espécies, quanto na determinação da aptidão dos indivíduos dessas espécies. Essas espécies são organizadas em níveis, onde a colaboração na geração das espécies se dá dos níveis mais baixos para os mais altos, e a colaboração na determinação das aptidões se dá dos níveis mais altos para os mais baixos. Os resultados obtidos indicam que a abordagem estudada é bastante promissora e pode-se obter, por meio dela, sistemas de classificação eficientes que apresentam desempenho semelhante ao de outras abordagens encontradas na literatura.
79

Analyse émergentiste des pratiques enseignantes en FLES : cas de l’appropriation de l’IFADEM au Bénin. Entre contextualisation, réflexivité et médiation / Emergentist analysis of teaching practises in « French as Foreign/Second Language Teaching» : The case of the appropriation of the IFADEM environment in Benin

Fantognon, Comlan Xavier 16 November 2015 (has links)
Située au carrefour de la didactique des langues et cultures et des sciences de l’éducation, la présente thèse porte sur l’appropriation, par les enseignants du cycle primaire au Bénin, de l’Initiative Francophone pour la Formation à Distance des Maîtres (IFADEM) en tant que dispositif de formation continue, en enseignement-apprentissage du FLES. L’objectif consiste à apporter des pistes pour améliorer l’appropriation du dispositif. A partir d’un modèle théorique d’appropriation, mis en place au regard d’une approche théorique transdisciplinaire et des spécificités du contexte d’étude, doublé d’une démarche de triangulation articulant enquêtes par questionnaires, par entretiens semi-directifs, d’auto-confrontation et par observations de pratiques effectives (situantes), nous nous sommes attachés à identifier les « indicateurs » d’appropriation ainsi que les « effets » du dispositif de formation sur les « pratiques pédagogiques effectives » des enseignants. Les théories holistiques de l’apprentissage des langues et spécifiquement l’éducation bilingue, le translanguaging et les théories sur l’enseignement-apprentissage de l’oral, ont constitué un socle pour l’analyse et la compréhension de la situation de recherche. La stabilité de nos analyses, offerte par le choix d’une méthodologie par triangulation, confirme que le parcours d’appropriation est déterminé par des relations d’interdépendance entre des facteurs situationnels (contextualisation), relationnels (relation avec les pairs) et individuels (self-system, réflexivité, recul épistémologique). Elle nous permet également d’aboutir aux conclusions suivantes : les enseignants bénéficiaires de la formation IFADEM font usage de la formation de façon instrumentale, et notamment des tâches qui leurs sont proposées pour améliorer l’enseignement oral du et en français afin de faire face au plurilinguisme. Ils sont exposés à plusieurs variations d’échelle, sources de contraintes et de tensions dans leurs activités pédagogiques, et ces dernières constituent un frein à l’appropriation du dispositif. L’analyse du processus d’appropriation au regard de l’émergentisme et des systèmes complexes d’activité permet d’aboutir au fait que les tensions générées par le déploiement du dispositif IFADEM font partie intégrante du processus de transformation de ce dernier. C’est l’absence de feed-back soutenu et institutionnalisé qui constitue une entrave à l’appropriation du dispositif. Afin de réagir positivement à ces écarts et de garantir l’appropriation du dispositif, le recours à la médiation ainsi qu’à une approche par tâches constituerait une voie intermédiaire. Elle permettrait notamment au dispositif de formation IFADEM, de s’inscrire dans une démarche co-évolutive, essentielle à l’équilibre des systèmes. C’est en tenant compte de l’ensemble de ces analyses et ajustements que cette recherche aboutit à l’élaboration d’un modèle d’appropriation. / This PhD thesis, situated at the crossroads of two domains – language and culture learning and teaching and learning sciences – deals with the way Beninese primary school teachers appropriated the IFADEM programme - « Initiative Francophone pour la Formation à Distance des Maîtres » (Francophone Initiative for Distance Education of Teachers), as a lifelong education environment in the teaching and learning of « French as Foreign/Second Language Learning ». Our purpose is to suggest new avenues aimed at improving the appropriation of this education environment. Our approach is based on a theoretical model of appropriation informed by a transdisciplinary theoretical stance and by the specifics of the context under study, but also on a triangulation method mixing questionnaire surveys, semi-directive interviews, self-confrontation interviews and observations of actual practises (situating). We try to identify the « indicators » of appropriation as well as the « effects » of the education environment on the « actual pedagogical practises » of teachers. Holistic theories of language learning – and more specifically bilingual education, translanguaging and the theories on oral skills development have given a foundation to the analysis and the comprehension of the research situation. The stability of our analyses, made possible by the choice of a triangulation methodology, confirms that the appropriation paths are determined by interdependency relations between factors of situational (contextualisation), relational (relationships with peers) and individual (self-system, reflexivity, epistemological distancing) natures. It also allows us to reach the following conclusions : the teachers who benefitted from the IFADEM training use it instrumentally and more specifically use the tasks they were proposed to improve the teaching of oral skills in and of French, in order to tackle the question of plurilingualism. These teachers are faced with several scale variations which engender constraints and tensions in their pedagogical activities, thus hindering the appropriation of the education environment. The analysis of the appropriation process in the light of emergentism and of complex systems of activity leads to the conclusion that the tensions generated by the implementation of the IFADEM progamm are part and parcel of its process of transformation. The absence of institutionalised and sustained feedback is the real hindrance to the appropriation of the education environment. In order to reduce these discrepancies in a positive way and to guarantee appropriation, turning to mediation and a task-based approach would constitute a middle way. In particular, it would allow the IFADEM environment to come within the scope of a co-evolutive approach, which is essential to the balance of systems. Taking into account all these analyses and adjustments helps this research to reach the elaboration of a model of appropriation.
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Co-evolutional anaylsis of the Na+,K+-ATPase’s β-subunit dimerization / Samevolutionär analys av Na+,K+-ATPas β-subenhet dimerisering

Bauer, Sebastian January 2023 (has links)
Does the active membrane transporter, Na+,K+-ATPase dimerize? If it does, whatis the functional benefit? Does it increase or decrease the turnover rate? Theseare still unanswered questions and current research topics. Previous studies havedemonstrated dimerizations in closely related proteins of the P-type ATPase family.For the Na+, K+-ATPase a first indication of dimerization has been shown viaFluorescence lifetime imaging microscopy (FLIM) or Fluorescence resonance energytransfer - Fluorescence correlation spectroscopy (FRET-FCS) experiments. Theprecise dimer structure, dimerization process, and its ultimate functional effecthowever, remain to be found. This master thesis approaches those questions froma co-evolutionary standpoint. It predicts a possible dimer structure by starting with amultiple sequence alignment, direct coupling analysis, and structural contact filteringalgorithm. This model would strengthen the dimerization model of a decreasedturnover rate due to a competitive behavior of two Na+, K+-ATPases for its energysource ATP. / Dimeriserar den aktiva membrantransporten Na+,K+-ATPas? Om den gör det,vad är den funktionella nyttan? Ökar eller minskar det omsättningshastigheten?Dessa är obesvarade frågor och rådande forskningsämnen. Tidigare studier hardemonstrerat dimeriseringar i nära relaterade proteiner av P-typ ATPas-familjen.För Na+, K+-ATPas har en första indikation av dimerisering visats via ”Flourescencelifetime imaging microscopy (FLIM)” eller ”Flourescence resonance energy transfer- Flourescence correlation spectroscopy (FRET-FCS)”. Den precisa dimerstrukturen,dimeriseringsprocessen och dess slutgiltiga funktionella effekt emellertid, återståratt ses. Detta examensarbete på masternivå närmar sig dessa frågor från ettsamevolutionärt perspektiv. Det förutser en möjlig dimerstruktur genom att utgåfrån en flersekvenslinjering, direkt kopplingsanalys och en strukturell kontaktfiltreringsalgoritm. Denna modell skulle stärka dimeriseringsmodellen av minskadomsättningshastighet till följd av tävlingsbeteende mellan två Na+,K+-ATPaser fördess energikälla ATP.

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