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Mesenchymal stem cells (MSCs) show great interest in cellular therapies. Their various characteristics such as their immuno-modulatory properties, their ability to differentiate, and also the secretion of factors, are numerous and promising for new clinical treatments for diseases where few therapies are proposed or have few efficiencies. The doses to be injected for significant results must be repeated and generally contain high quantities of cells (106 cells kg-1 per patient approx). Large scale production methods must be implemented to meet the demand, and in the least costly way possible. In this PhD work, the main objective was to develop a scalable process adapted to these support-dependent cells. For this end, a first study allowed to understand part of the mechanisms of interaction of cells with their growth supports, the microcarriers. The adhesion time but also the cell migrations between microcarriers were characterized and evaluated. A strategy of fed-batch mode strategy with microcarriers addition at specific times in the culture was also proposed. Following this, the second part of the study of this work was to determine the efficiency on larger scale expansion process (1.5 L), using of innovative microcarriers developed by the partner teams of the ‘ImprovesStem’ European project. Several microcarriers candidates with chemically modified surface proved to be promising for the expansion of Wharton’s jelly stem cells. Finally, in the last part of the thesis, an innovative process based on the removal of empty microcarriers, avoiding the risk of deleterious frictions between highly concentrated microcarriers was proposed. Moreover, an on-line monitoring of viable cell concentration was carried-out in the stirred tank bioreactor. Innovative commercial microcarriers, soluble under the action of enzymes, were used in this last part of the study. An improvement of the expansion factor (by a factor of 1.5) was obtained in this continuous-perfused mode of culture in the stirred bioreactor. In addition, these enzymatically-soluble commercial microcarriers allowed for an excellent detachment yield, essential to consider their use in cell therapy.; Les cellules souches mésenchymateuses (CSM) ont un fort intérêt en utilisation clinique. Leurs différentes caractéristiques telles que leurs propriétés immuno-modulatrices, leur capacité à se différencier, et aussi la sécrétion de facteurs, sont nombreuses et prometteuses pour le traitement clinique de maladies où peu de thérapies sont proposées ou sont peu efficaces. Cependant, les doses à injecter pour des résultats cliniques significatifs doivent être répétées et contiennent généralement des quantités importantes de cellules (106 cellules kg-1 par patient). Ainsi, des méthodes de production à grande échelle doivent être mises en œuvre pour répondre à la demande, tout en minimisant les coûts de production. Dans ce travail de thèse, une première étude a permis de comprendre une partie des mécanismes d’interaction des cellules avec leurs supports de croissance, les microporteurs. Le temps d’adhérence et des migrations cellulaires entre microporteurs ont pu être mesurés et étudiés. Une stratégie d’ajout de microporteurs à des temps spécifiques de la culture a été proposée. Suite à cela, la deuxième partie d’étude de ces travaux a été de déterminer les performances d’expansion du procédé réalisé à plus grande échelle (1.5 L), en utilisant des microporteurs innovants développés par les équipes partenaires du projet européen, et présentant des chimies de surfaces variées. Plusieurs microporteurs candidats se sont révélés prometteurs pour l’expansion des cellules souches de la gelée de Wharton. Enfin, la dernière partie de la thèse a été consacrée au développement d’un procédé innovant reposant sur le soutirage de microporteurs vides, diminuant le risque de frictions délétères entre des microporteurs très concentrés, a été proposé. De plus, un contrôle en ligne de la concentration en cellules vivantes a été effectué dans le bioréacteur à cuve agitée. Des microporteurs commerciaux innovants, solubles sous l’action d’enzymes, ont été utilisés dans cette dernière partie. Une amélioration du facteur d’expansion (d’un facteur 1.5) a été obtenue par l’utilisation de ce mode continu et perfusé en bioréacteur. De plus, ces microporteurs, solubles sous l’action d’enzymes, ont permis un excellent rendement de détachement cellulaire, élément essentiel pour envisager l'utilisation des CSMs en thérapie cellulaire à un coût contrôlé.

Conférence EIAH 2015; Dans cet article nous discutons le concept de gamification en nous appuyant sur une revue de la littérature, sur les premiers retours d’expérience etsur une enquête auprès des utilisateurs de Classcraft, un jeu de rôle utilisant une plateforme numérique et une application pour ordiphones et développé pour satisfaire aux besoins des enseignants du secondaire dans la gestion de leurs classes. Nous argumentons pour l’utilisation du terme ludicisation pour souligner que transformer une situation en jeu ne consiste pas à utiliser de manière mécanique des éléments qui auraient une valeur ludique intrinsèque mais plutôt, selon une vision non essentialiste du jeu, à métaphoriser cette situation pour concevoir un espace de réflexivité au sein duquel la nature et le sens des interactions sont modifiés.

International audience; This book presents a range of educational approaches and ideas around learning with and about geomedia, taking into account the potential as well as the risks and challenges associated with the use geomedia in education. This includes understanding the inherently biasednature of maps and other spatial representations; the power of geomedia produced by institutions, as well as the power of geomedia produced by lay persons; the use of geoinformation in the control and surveillance of individuals and groups, and the opportunities of georeferenced data to foster innovative knowledge. Addressing these aspects in essence means preparing students for an emerging Geoinformation society.

International audience; Today, many teachers have, on one hand, the opportunity to benefit from powerful geomedia technologies to improve their lessons, but on the other hand they have to deal with problems and difficulties handling and making sense of them. Nevertheless, remaining in ignorance is not a realistic option at all as today geomedia technologies pervade everyday life. This introductory chapter to a book dedicated to the use of geomedia in secondary education presents the Challenges and opportunities emerging with the societal impact of geomedia need to be addressed through education

International audience; This paper is an introduction to a workshop that intends to promote a collaborative work on the use of digital epistemic games. The participants will have the opportunity to discuss the impact the choice of tools and game design criteria have on epistemic interactions. We (1) advocate the consideration of digital epistemic games as learning situations adapted to new learners, (2) describe a game designed for the purposes of our research, (3) describe the methodology that we used to track epistemic interactions and (4) give an overview of the objectives of the workshop.

International audience; This paper relates to an empirical study about the use of a Game-Based Learning approach for Sustainable Development Education. We de signed Clim@ction, an online multiplayer game which aims at fostering epistemic interactions between French and Canadian secondary students that are involved in designing an innovative project for the implementation of “Green” energy. The study aims at addressing the following questions: How to design a realistic situation which allows the students to be engaged as citizens and to grasp the complexity of the world? Which elements should be taken into account for the game design in order to permit the learner/gamer to be engaged in epistemic activities? The digital records of students’ interactions with the digital platform permits to draw an epistemic models of students (Wenger, 1987). The data collected during the study include as well the recording of the teachers during the focus groups dedicated to the design of the game and the recording of the students after the game session. Our preliminary results permit to identify several key factors that should be taken into account in order to foster epistemic interactions between students.

International audience; With laptops, mobile phones, tablets and broadband wireless access becoming more widely available, Web 2.0 is now entering schools. This changes the way students work and communicate, altering their relationship with knowledge, and generating new objectives for media literacy in the digital society. Thus, schools face new challenges and this paper aims at highlighting four of them. A first challenge relates to trust. Web 2.0 opens the classroom to the world and educators have to face new dangers and irrelevant uses, while bringing their students to gain better access to information and culture. The second challenge relates to teachers' professional identities. The role of teachers is changing as Web 2.0 tools are begin used by students and policymakers should take this into account. A third challenge relates to a growing need to control working time, timetable organisation and rhythm in schools. The fourth challenge that we underline is the need for common rules that allow the students to benefit from the opportunities offered by Web 2.0 to develop their autonomy and to foster ethical practices.

International audience; In Sète, a small French southern town nearby the Mediterranean Sea, six companies are competing to implement new energies into the city. The companies are specialized in different “green” energies: heat pumps, windmills, ocean wave energy, photovoltaics and methanization. Each of them has to convince the committee tender responsible for the call for project that their project is the best for a sustainable development of the city. But they have to face cons from an active local association of citizens before they vote to choose the best project. The debate is tricky and the competition is merciless. Each one is aware of the importance of the stakes and is deeply involved in the struggle… but this is “only a game”. The “mayor of the city” is a secondary teacher. The “companies”, the “committee tender” and “association of inhabitants” are the different characters playing by secondary students.This role-playing game has been designed with geotechnologies. The different characters get data from a virtual globe. They use it to locate their project and to demonstrate its impact on the environment. The different characters have to judge the relevance of the projects on the field. To do that, they use pocket PCs with GPS functionalities that display interviews of local “inhabitants” when they reach the places where the projects are planned to be implemented. They get information from these interviews and from the field itself. Therefore the game includes the use of Augmented Reality.In this paper we describe an empirical research into the uses of geotechnologies to design a role-playing game for the development of citizenship. The research questions focus on the elements that the teacher should take into account to design such a role-playing game. We address the question of the added value of geotechnologies to design complex learning situations. Then, we discuss the relevance of geotechnologies to design a Game-Based-Learning situation which aims at developing citizenship for secondary students.