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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.
161

The Unintended Consequences of Industry Mandates: How EMV is Changing the U.S. Payments Landscape

Thrasher, Jessica January 2018 (has links)
The 2015 mandate of Europay MasterCard and Visa (EMV) “chip card” technology in the U.S. left the payments market primed for the adoption of alternative technologies. The goal of this study is to determine the factors that contribute to the adoption of new, alternative payment technologies by integrating the Technology Acceptance Model (TAM) and Switching Cost Theory and operationalizing both theories in a consumer context. Through a survey of 210 chip card and mobile payment users, this study finds the TAM dimensions of self-efficacy, perceived usefulness, and social influence are key determinants of a user’s propensity to use a new technology in a mandated consumer context and introduces switching costs as an important antecedent to a consumer’s likelihood to use an alternative payment technology. More generally, this work integrates those theories to gain insight into how industry mandates influence user behavior with regards to consumer acceptance of alternative technologies. / Business Administration/Interdisciplinary
162

Fostering Financial Inclusion in Developing Countries: Predicting User Acceptance of Mobile Wallets in Cameroon

Fosso Wamba, S., Queiroz, M.M., Blome, C., Sivarajah, Uthayasankar 14 September 2020 (has links)
Yes / Financial inclusion is a vital development priority for countries worldwide. Mobile wallet (m-wallet) is considered as a disruptive payment method that will substitute the traditional physical wallet to achieve the so-called cashless society and enables financial inclusion. This study aims at developing and testing a research model that integrates a set of technology factors (perceived usefulness, perceived ease of use, fun to use, monetary value), external factors (peer influence and perceived status benefit), and cultural factors (humane orientation and societal collectivism) to assess the intention to adopt and use m-wallet, for financial inclusion, in a developing country. The proposed conceptual model is tested using data collected from 621 m-wallet users in Cameroon. The model explains 47.5% of the variance of the actual use of m-wallet and 32.90% of the variance of financial inclusion. Finally, implications for research and practice are discussed.
163

Critical success factors of the digital payment infrastructure for developing economies

Singh, N.K., Sahu, G.P., Rana, Nripendra P., Patil, P.P., Gupta, B. 25 September 2020 (has links)
Yes / This paper studies the Critical Success Factors’ (CSFs) for the adoption of Digital Payment System in India. There are few studies about the literature on CSFs for the adoption of the digital payment system in the Indian context. This study is an attempt to cover this gap. In this study, we reviewed the theories for adoption model at the individual level used in Information System (IS) and discussed four technology model including “Technology Acceptance Model” (TAM). Ten factors have been identified with extensive literature review and review of selected models namely; Perceived Ease of Use, Perceived functional benefits, Awareness, Availability of Resources, Government as a policy maker, Performance Expectancy, Social Influence, Price Value, Experience & Habit, and Risk-taking ability. An expert from academic industry has been taken as a reviewer or consultant of the selected variables. The CSFs may ensure that they are the predictors and the important factors for adoption of digital payments system in India. The study mainly uses the deductive approach to consider the primary and secondary sources of data. The analyses of these models take into account through Interpretive Structural Modeling (ISM) methodology and develop a model for effective adoption of Digital Payment System in India. The paper also makes future recommendations for further research studies.
164

Understanding AI adoption in manufacturing and production firms using an integrated TAM-TOE model

Chatterjee, S., Rana, Nripendra P., Dwivedi, Y.K., Baabdullah, A.M. 07 May 2021 (has links)
Yes / This study aims to identify how environmental, technological, and social factors influence the adoption of Industry 4.0 in the context of digital manufacturing. The Industry 4.0 era has brought a breakthrough in advanced technologies in fields such as nanotechnology, quantum computing, biotechnology, artificial intelligence, robotics, the Internet of Things, fifth-generation wireless technology, fully autonomous vehicles, 3D printing and so on. In this study, we attempted to identify the socioenvironmental and technological factors that influence the adoption of artificial intelligence embedded technology by digital manufacturing and production organizations. In doing so, the extended technology-organization-environment (TOE) framework is used to explore the applicability of Industry 4.0. A conceptual model was proposed that used an integrated technology acceptance model (TAM)-TOE model and was tested using survey-based data collected from 340 employees of small, medium and large organizations. The results highlight that all the relationships, except organizational readiness, organizational compatibility and partner support on perceived ease of use, were found to be significant in the context of digital manufacturing and production organizations. The results further indicated that leadership support acts as a countable factor to moderate such an adoption.
165

Designkrav för ett GIS-verktyg inom geografiundervisning på gymnasienivå

Wahlgren, Robin, Björnstedt, Carl January 2024 (has links)
Geographic Information Systems (GIS) has since it originated been making its wayinto different types of industries and higher education. However, one of the purposes regarding the teaching of geography in the upper secondary school in Swedenis to let students visualize and analyze spatial data by using GIS-tools. Previous research states that a broader implementation of GIS in the teaching of geography canbring opportunities such as new and more fun ways of teaching at the same time asstudents learn and develop essential knowledge for the future. Research howeverstates that there are constraints connected to the implementation of GIS in k-12 education and one of these originates from the idea that students and teachers potentially lack knowledge and have an overall negative attitude towards GIS. The implementation of GIS-tools which are adapted to fit the purpose of education at the desired level are therefore regarding to previous research a potential way of dealingwith this issue. This study aims to examine which requirements are to be included ina GIS-application from a teacher’s perspective to enhance usability and ease of use ofsuch tools. A prototype of a GIS-tool is going to be developed and evaluated together with this study to help determine the requirements to be expected from upper secondary school teachers regarding usability and ease of use.The research strategy chosen for this study is Design science. Semi-structured interviews have been conducted together with upper secondary school teachers at twodifferent occasions in this study. The first sets of interviews were conducted for collecting initial requirements for the prototype and the second sets of interviews wereconducted to evaluate the prototype. A theoretical framework has been used for thisstudy, both for supporting in creating questions for the interviews and for supporting in conducting two sets of deductive thematic analysis on the data collected. Thechosen theoretical framework for this study is The Technology Acceptance Model 3(TAM3), which fits the aim of this study as it has been able to assist in analysingtraits regarding perceived usefulness and perceived ease of use regarding a system.This study has developed a set of desired functional and non-functional requirementsfor GIS-applications intended to be used for the teaching of geography at the uppersecondary school level in Sweden. The result of this study also brings knowledgeabout other potential constraints regarding GIS-applications and its implementationin an educational setting; these regard the lack of student’s general computer skills,subject related knowledge, and resources. / Geografiska informationssystem (GIS) har under en längre tid varit en framväxandedel inom olika industrier och utbildning på högre nivå. Användning av tekniska redskap som GIS för att visualisera och analysera geografiska data ska enligt Skolverket iSverige ingå som ett syfte i geografiundervisning på gymnasial nivå. GIS som en delav grund- och gymnasieskolan har påvisats ha möjligheter att skapa roliga och moderna aktiviteter inom undervisning samtidigt som elever utvecklar goda kunskaperinför framtiden. Tidigare forskning har dock kommit fram till att GIS har svårigheteratt implementeras som en del av grund- och gymnasieskolans utbildning. Kunskapoch attityd gentemot GIS har påvisats bristande hos lärare och elever och verktyg anpassade för utbildning på lägre nivå är något tidigare forskning menar kan vara enmöjlig väg till förbättring. Syftet med studien är att undersöka vilka designkrav geografilärare ställer på en GIS-applikation för att underlätta användning av GIS som ettverktyg i deras undervisning. Detta genom att utveckla och utvärdera en prototypsom ämnas kunna fastställa krav relaterat till vad geografilärare anser att ett GISverktyg ska innefatta i form av användbara och användarvänliga egenskaper.Design science-metodologin har använts som vald forskningsstrategi för denna studie.Semistrukturerade intervjuer har genomförts med geografilärare på gymnasienivåfrån diverse skolor i Sverige, detta för både kravinsamling och utvärdering av studiens utvecklade prototyp. Ett teoretiskt ramverk har använts som stöd för skapandetav intervjufrågor och vid genomförandet av den deduktiva tematiska analysen idenna studie. Det teoretiska ramverket är The Technology Acceptance Model 3 (TAM3),vilket har passat denna studie då det har agerat som ett stöd för att analysera egenskaper relaterade till uppfattad användbarhet och uppfattad användarvänlighet förnågot system.Studien resulterade i att funktionella och icke-funktionella krav framställdes vilkageografilärare ställer på en GIS-applikation för att användas i undervisning inom geografiämnet. Resultatet lyfter även omkringliggande problematik gällande GISapplikationer med faktorer relaterade till bristande datorvana hos elever, ämneskunskap, samt resurser.
166

Développement touristique et développement local : la communauté lagunaire à Tam Giang-Cau Hai, province de Thùa Thiên Hué, Vietnam / Tourist development and local developpement : The lagoon community at Tam Giang-Cau Hai province of Thua Thien Hue's, Vietnam

Dam, Duy Long 17 November 2017 (has links)
Thừa Thiên Huế dispose d’une situation géographique stratégique, possédant des paysages somptueux, des villages artisanaux et d’une culture très riche avec deux patrimoines culturels mondiaux... Parmi les ressources naturelles potentielles de Hue, la lagune de Tam Giang - Cầu Hai (TG-CH), avec ses ressources précieuses, est une nouvelle destination touristique de cette province. À TG-CH, les activités touristiques sont apparues depuis 2010. Mais en réalité, le tourisme à la lagune de TG-CH ne montre pas vraiment qu’il est un outil efficace pour lutter contre la pauvreté pour la communauté lagunaire locale. Cette étude vise à un développement local durable en analysant plusieurs facteurs. Les analyses profondes sur les impacts touristiques, sur la participation communautaire dans le tourisme ont une relation directe avec la valeur perçue par la communauté locale sur le tourisme à TG-CH. Spécialement, une proposition initiale du « tourisme à la ville fantôme » dans la lagune de TG-CH montre une destination unique dans le monde entier que les responsables de Thừa Thiên Huế ne connaissent pas. Pour la première fois, la culture locale devient une clé importante pour comprendre, pour expliquer les pratiques des communautés locales. Cette recherche va être encore développée pour un développement local durable à TG-CH. / Thừa Thiên Huế inherites a strategic geographic position with many majestic landscapes, traditional villages and a diverse culture with two world cultural heritages. Among various potential natural resources of the place, Tam Giang – Cầu Hai Lagoon (TG-CH), with its precious resources, is an emerging tourist destination of the province. Althought tourism has established at TG-CH since 2010, it, in fact, has not shown as an effective tool for poverty alleviation. This research is aiming to a sustainable development of the area through analysing various factors. Analysises on the impacts of tourism and the involvement of local community in tourism have a very strong connection with the community perceived value in tourism. Specifically, a proposal for a model “tourism in the ghost town” at TG-CH would bring a unique aspect of a lost world which could not even be in the mind Thừa Thiên Huế authorities. For the first time, local culture becomes a significant key to understand and elaborate social changes. This research will continuously develop toward the sustainable development of TG-CH.
167

Le rgyalrong zbu, une langue tibéto-birmane de Chine du Sud-ouest. Une étude descriptive, typologique et comparative. / Zbu Rgyalrong, a Tibeto-Burman language of Southwestern China. A descriptive, typological and comparative study.

Gong, Xun 22 June 2018 (has links)
Cette thèse comporte deux volets complémentaires : d'une part, une description phonologique et morphologique du rgyalrong zbu, langue du groupe rgyalronguique du sino-tibétain ; d'autre part, une reconstruction de l'histoire de la flexion verbale de cette langue. Le volet descriptif vise à l'exhaustivité dans la description de la phonologie de cette langue, et pose les bases d'une grammaire de référence qui ambitionne notamment de situer sa morphologie flexionnelle dans une perspective de linguistique générale. Sur la base de cette description, élaborée au fil d'enquêtes de première main sur cette langue fortement en danger, un volet diachronique est proposé. Celui-ci contribue au projet général d'une reconstruction du groupe rgyalronguique, entreprise collective qui a des implications importantes pour la reconstruction du sino-tibétain dans son ensemble. Parmi les principaux résultats figurent une reconstruction du système de marquage de temps-aspect-modalité (TAM) de l'ancêtre commun le plus récent au japhug, au tshobdun et au zbu, désigné ici comme « proto-rgyalrong supérieur ». Cette reconstruction ouvre une perspective nouvelle pour bien distinguer entre éléments hérités et développements secondaires dans chacune des langues rgyalronguiques, ainsi qu'au sein du groupement supérieur (qianguique). Le volet diachronique comporte aussi un traitement comparatif de quelques verbes du zbu, à la lumière des données des langues qianguiques et lolo-birmanes, qui pourra servir de modèle pour un dictionnaire étymologique des verbes rgyalronguiques. / This thesis focuses on Zbu Rgyalrong, a Sino-Tibetan language of the Rgyalrongic branch, and consists of both a phonological and morphological description of the language and a reconstruction of the history of its verb inflection. This thesis aims at descriptive exhaustivity for its phonology and attempts to lay the foundation of a reference grammar, in order to characterize its inflectional morphology in the perspective of general linguistics. Based on the description of this highly endangered language, the thesis contains a diachronic discussion, which contributes to the project of reconstructing Proto-Rgyalrongic, a collective enterprise which has important implications for the reconstruction of Sino-Tibetan as a whole. Notably, a reconstruction is proposed of the time-aspect-modality (TAM) marking system of Proto-Upper-Rgyalrong, the most recent common ancestor of Japhug, Tshobdun and Zbu. This reconstruction provides new perspectives for distinguishing between inherited elements and secondary developments in each Rgyalronguic language, as well as within the kindred Qiangic languages. Also included in the diachronic part is a comparative treatment of some verbs in Zbu, examined with data from other Qiangic and Lolo-Burman languages, which can serve as a model for an etymological dictionary of Rgyalrongic verbs.
168

Fatores que influenciam a aceita??o de pr?ticas avan?adas de gest?o de seguran?a da informa??o: um estudo com gestores p?blicos estaduais no Brasil

Nobre, Anna Cl?udia dos Santos 04 September 2009 (has links)
Made available in DSpace on 2014-12-17T13:53:24Z (GMT). No. of bitstreams: 1 AnnaCSN.pdf: 3032779 bytes, checksum: c9b62b38c5e42ff883e6b2946ccff0e1 (MD5) Previous issue date: 2009-09-04 / This study examines the factors that influence public managers in the adoption of advanced practices related to Information Security Management. This research used, as the basis of assertions, Security Standard ISO 27001:2005 and theoretical model based on TAM (Technology Acceptance Model) from Venkatesh and Davis (2000). The method adopted was field research of national scope with participation of eighty public administrators from states of Brazil, all of them managers and planners of state governments. The approach was quantitative and research methods were descriptive statistics, factor analysis and multiple linear regression for data analysis. The survey results showed correlation between the constructs of the TAM model (ease of use, perceptions of value, attitude and intention to use) and agreement with the assertions made in accordance with ISO 27001, showing that these factors influence the managers in adoption of such practices. On the other independent variables of the model (organizational profile, demographic profile and managers behavior) no significant correlation was identified with the assertions of the same standard, witch means the need for expansion researches using such constructs. It is hoped that this study may contribute positively to the progress on discussions about Information Security Management, Adoption of Safety Standards and Technology Acceptance Model / Este estudo analisa os fatores que influenciam os gestores p?blicos na ado??o de pr?ticas van?adas de Gest?o de Seguran?a da Informa??o. A pesquisa utilizou como base assertivas a Norma de Seguran?a ISO 27001:2005 e modelo te?rico baseado no TAM (Technology Acceptance Model) descrito em Venkatesh e Davis (2000). O m?todo adotado foi a esquisa de campo de alcance nacional que contou com a participa??o de oitenta gestores p?blicos dos Estados do Brasil, sendo todos coordenadores na ?rea de gest?o e planejamento dos governos estaduais. A abordagem da pesquisa foi quantitativa e foram utilizados m?todos de estat?stica descritiva, an?lise fatorial e regress?o linear m?ltipla para an?lise dos dados. Os resultados da pesquisa apresentaram correla??o entre os construtos do modelo TAM (facilidade na utiliza??o, percep??o sobre a utilidade, atitude e inten??o de utiliza??o) e a concord?ncia com as assertivas elaboradas de acordo com a norma ISO 27001, demonstrando que estes fatores influenciam os gestores na ado??o de tais pr?ticas. J? as outras vari?veis independentes do modelo (perfil organizacional, perfil demogr?fico e comportamental dos gestores) n?o tiveram correla??o significante com as assertivas da referida norma, demonstrando necessidade de amplia??o de pesquisas com utiliza??o de tais construtos. Espera-se que este estudo possa contribuir de forma positiva ao avan?o nas discuss?es sobre o tema Gest?o de Seguran?a da Informa??o e Ado??o de Normas de Seguran?a, bem como, Modelos de Aceita??o de Tecnologia
169

Fatores cr?ticos de sucesso como antecedentes da aceita??o de um sistema de informa??o em uma universidade federal

Yoshino, Cristina Kazumi Nakata 03 September 2010 (has links)
Made available in DSpace on 2014-12-17T13:53:26Z (GMT). No. of bitstreams: 1 CristinaKNY_DISSERT.pdf: 2647899 bytes, checksum: 38fec83f99c6340d8c2475bec099d1b8 (MD5) Previous issue date: 2010-09-03 / In recent decades the public sector comes under pressure in order to improve its performance. The use of Information Technology (IT) has been a tool increasingly used in reaching that goal. Thus, it has become an important issue in public organizations, particularly in institutions of higher education, determine which factors influence the acceptance and use of technology, impacting on the success of its implementation and the desired organizational results. The Technology Acceptance Model - TAM was used as the basis for this study and is based on the constructs perceived usefulness and perceived ease of use. However, when it comes to integrated management systems due to the complexity of its implementation,organizational factors were added to thus seek further explanation of the acceptance of such systems. Thus, added to the model five TAM constructs related to critical success factors in implementing ERP systems, they are: support of top management, communication, training, cooperation, and technological complexity (BUENO and SALMERON, 2008). Based on the foregoing, launches the following research problem: What factors influence the acceptance and use of SIE / module academic at the Federal University of Para, from the users' perception of teachers and technicians? The purpose of this study was to identify the influence of organizational factors, and behavioral antecedents of behavioral intention to use the SIE / module academic UFPA in the perspective of teachers and technical users. This is applied research, exploratory and descriptive, quantitative with the implementation of a survey, and data collection occurred through a structured questionnaire applied to a sample of 229 teachers and 30 technical and administrative staff. Data analysis was carried out through descriptive statistics and structural equation modeling with the technique of partial least squares (PLS). Effected primarily to assess the measurement model, which were verified reliability, convergent and discriminant validity for all indicators and constructs. Then the structural model was analyzed using the bootstrap resampling technique like. In assessing statistical significance, all hypotheses were supported. The coefficient of determination (R ?) was high or average in five of the six endogenous variables, so the model explains 47.3% of the variation in behavioral intention. It is noteworthy that among the antecedents of behavioral intention (BI) analyzed in this study, perceived usefulness is the variable that has a greater effect on behavioral intention, followed by ease of use (PEU) and attitude (AT). Among the organizational aspects (critical success factors) studied technological complexity (TC) and training (ERT) were those with greatest effect on behavioral intention to use, although these effects were lower than those produced by behavioral factors (originating from TAM). It is pointed out further that the support of senior management (TMS) showed, among all variables, the least effect on the intention to use (BI) and was followed by communications (COM) and cooperation (CO), which exert a low effect on behavioral intention (BI). Therefore, as other studies on the TAM constructs were adequate for the present research. Thus, the study contributed towards proving evidence that the Technology Acceptance Model can be applied to predict the acceptance of integrated management systems, even in public. Keywords: Technology / Nas ?ltimas d?cadas o setor p?blico vem sofrendo press?es com vistas a melhorar seu desempenho. A utiliza??o da Tecnologia da Informa??o (TI) tem sido uma ferramenta cada vez mais empregada na tentativa de alcan?ar esse objetivo. Dessa forma, passou a ser uma importante quest?o nas organiza??es p?blicas, e em particular nas institui??es de ensino superior, verificar quais fatores influenciam a aceita??o e o uso da tecnologia, impactando no sucesso de sua implementa??o e nos resultados organizacionais almejados. O Modelo de Aceita??o da Tecnologia TAM foi utilizado como base para o presente estudo e fundamenta-se nos construtos utilidade percebida e facilidade de uso percebida. No entanto, quando se trata de sistemas integrados de gest?o, devido ? complexidade de sua implanta??o, acrescentaram-se fatores organizacionais para assim buscar maior explica??o da aceita??o desses sistemas. Assim, acrescentaram-se ao modelo TAM cinco construtos relacionados aos fatores cr?ticos de sucesso na implementa??o de sistemas ERP, s?o eles: apoio da alta administra??o, comunica??o, treinamento, coopera??o, e complexidade tecnol?gica (BUENO e SALMERON, 2008). Com base no exposto, lan?a-se o seguinte problema de pesquisa: quais fatores influenciam a aceita??o e uso do SIE/m?dulo acad?mico na Universidade Federal do Par?, a partir da percep??o dos usu?rios t?cnicos e docentes? O objetivo geral da pesquisa foi identificar a influ?ncia de fatores organizacionais e comportamentais como antecedentes da inten??o comportamental de uso do SIE/m?dulo acad?mico na UFPA sob a perspectiva dos usu?rios docentes e t?cnicos. A presente pesquisa ? aplicada, explorat?ria e descritiva, de natureza quantitativa com a aplica??o de um survey, e a coleta de dados se deu por meio de question?rio estruturado aplicado a uma amostra composta por 229 docentes e 30 t?cnico-administrativos. A an?lise de dados se deu atrav?s de estat?sticas descritivas e modelagem de equa??o estrutural com a t?cnica de m?nimos quadros parciais (Partial Least Square-PLS). Primeiramente efetuou-se a avalia??o do modelo de mensura??o, no qual foram verificadas a confiabilidade, validade convergente e discriminante para todos os indicadores e construtos. Em seguida, o modelo estrutural foi analisado, com a utiliza??o de bootstrap como t?cnica de reamostragem. Na avalia??o das signific?ncias estat?sticas, todas as hip?teses formuladas foram suportadas. O coeficiente de determina??o (R?) foi considerado alto ou m?dio em 5 das 6 vari?veis end?genas, assim o modelo consegue explicar 47,3% da varia??o da inten??o comportamental. Ressalta-se que, dentre os antecedentes da inten??o comportamental (BI) analisados no presente estudo, utilidade percebida ? a vari?vel que possui maior efeito sobre a inten??o comportamental, seguida pela facilidade de uso (PEU) e a atitude (AT). Dentre os aspectos organizacionais (fatores cr?ticos de sucesso) estudados, complexidade tecnol?gica (TC) e treinamento (TRE) foram aqueles com maior efeito sobre a inten??o comportamental de usar, apesar desses efeitos serem inferiores aos produzidos pelos fatores comportamentais (origin?rios do TAM). Destaca-se, ainda, que o apoio da alta administra??o (TMS) apresentou, entre todas as vari?veis, o menor efeito sobre a inten??o de usar (BI) e foi seguida pela comunica??o (COM) e coopera??o (CO), as quais exercem um baixo efeito sobre a inten??o comportamental (BI). Portanto, conforme outros estudos, os construtos relativos ao TAM mostraram-se adequados para a presente pesquisa. Dessa maneira, o estudo contribuiu no sentido de demonstrar ind?cios de que o Modelo de Aceita??o da Tecnologia pode ser aplicado ? predi??o da aceita??o de sistemas integrados de gest?o, mesmo em organiza??es p?blicas.
170

Implication de la protéine S, une protéine vitamine K-dépendante, dans la phagocytose et les effets anti-tumoraux des cellules souches du cerveau / Involvement of protein S, a vitamin K- dependent protein, in the phagocytosis and anti-tumor effects of brain stem cells

Ginisty, Aurélie 09 December 2014 (has links)
Des cellules souches neurales (CSN) persistent dans le cerveau de mammifères adultes, y compris l'Homme. Les CSN participent à l'homéostasie tissulaire en générant de nouveaux neurones, permettant le remplacement de certains neurones morts. Cependant, la production de nouvelles cellules se fait en excès et plus de la moitié des cellules nouvellement générées meurent. Les cellules mortes ainsi que leurs débris doivent être éliminés par phagocytose. Dans une première partie de ma thèse, nous avons montré pour la première fois, que les CSN sont capables de phagocytose et que cette activité des CSN est régulée par la protéine S (ProS), une protéine vitamine-K dépendante, et son récepteur MerTK. Une rupture de l'homéostasie tissulaire conduit à des pathologies dont les cancers. Les interactions entre les CSN et des tumeurs cérébrales, les gliomes, sont duelles et étroites : des CSN dont la prolifération est dérégulée seraient à l'origine des tumeurs, mais, à l'inverse, les CSN saines peuvent migrer vers les gliomes et inhiber leur croissance. Dans une deuxième partie de ma thèse, nous avons confirmé l'effet anti-tumoral des CSN et nous avons établi que la ProS sécrétée par les gliomes attire les CSN vers la tumeur d'une part, et d'autre part, que les CSN diminuent la croissance tumorale par la sécrétion de leur ProS. Nous démontrons de plus, que ce processus s'accompagne d'une mort cellulaire des gliomes dont les débris sont phagocytés par les CSN. Mon travail de thèse a permis d'identifier de nouveaux mécanismes impliqués dans le maintien de l'homéostasie tissulaire par les CSN en conditions physiopathologiques. / Neural stem cells (NSC) persist in the brain of adult mammals, including humans. NSC contribute to tissue homeostasis maintenance through the genesis of new neurons that replace part of the cells that are maybe lost. However, the production of new cells is in excess and half of the newly generated cells die. Dead cells and their debris must be removed by phagocytosis. NSC express protein S (ProS) and its receptors, which are involved in phagocytosis. During the first part of my PhD thesis, we established for the first time, using in vitro and in vivo experiments, that NSC possess a phagocytic activity which is regulated by protein S (ProS), a vitamin K-dependent protein, and its receptor MerTK. Tissue homeostasis disruption leads to diseases such as cancers. Interactions between the NSC and brain tumors such as gliomas are dual and complex: glioma may arise from transformed NSC, but, conversely, normal NSC migrate towards glioma and inhibit their growth. Our study confirms the anti-tumoral effect of NSC and demonstrates, for the first time that ProS secreted by gliomas acts on Tyro-3 to attract NSC and that NSC secrete ProS which reduces tumor growth of ProS. In addition, we show that this process results in the death of glioma cells that are then phagocytosed by NSC. Our highlights identified novel mechanisms by which NSC contribute to tissue homeostasis in pathophysiological conditions.

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